Update capa/features/extractors/dnfile/extractor.py

Co-authored-by: Moritz <mr-tz@users.noreply.github.com>

.github/CONTRIBUTING.md

@@ -31,7 +31,7 @@ This project and everyone participating in it is governed by the [Capa Code of C
 
 ### Capa and its repositories
 
-We host the capa project as three Github repositories:
+We host the capa project as three GitHub repositories:
   - [capa](https://github.com/mandiant/capa)
   - [capa-rules](https://github.com/mandiant/capa-rules)
   - [capa-testfiles](https://github.com/mandiant/capa-testfiles)

.github/mypy/mypy.ini

@@ -21,9 +21,6 @@ ignore_missing_imports = True
 [mypy-flirt.*]
 ignore_missing_imports = True
 
-[mypy-smda.*]
-ignore_missing_imports = True
-
 [mypy-lief.*]
 ignore_missing_imports = True
 
@@ -48,6 +45,9 @@ ignore_missing_imports = True
 [mypy-ida_bytes.*]
 ignore_missing_imports = True
 
+[mypy-ida_nalt.*]
+ignore_missing_imports = True
+
 [mypy-ida_kernwin.*]
 ignore_missing_imports = True
 
@@ -60,6 +60,9 @@ ignore_missing_imports = True
 [mypy-ida_loader.*]
 ignore_missing_imports = True
 
+[mypy-ida_segment.*]
+ignore_missing_imports = True
+
 [mypy-PyQt5.*]
 ignore_missing_imports = True
 
@@ -76,4 +79,7 @@ ignore_missing_imports = True
 ignore_missing_imports = True
 
 [mypy-dncil.*]
-ignore_missing_imports = True
+ignore_missing_imports = True
+
+[mypy-netnode.*]
+ignore_missing_imports = True

.github/pyinstaller/hooks/hook-smda.py

@@ -1,5 +0,0 @@
-# Copyright (C) 2020 Mandiant, Inc. All Rights Reserved.
-import PyInstaller.utils.hooks
-
-# ref: https://groups.google.com/g/pyinstaller/c/amWi0-66uZI/m/miPoKfWjBAAJ
-binaries = PyInstaller.utils.hooks.collect_dynamic_libs("capstone")

.github/pyinstaller/pyinstaller.spec

@@ -6,31 +6,6 @@ import subprocess
 import wcwidth
 
 
-# git output will look like:
-#
-#     tags/v1.0.0-0-g3af38dc
-#         ------- tag
-#                 - commits since
-#                   g------- git hash fragment
-version = (
-    subprocess.check_output(["git", "describe", "--always", "--tags", "--long"])
-    .decode("utf-8")
-    .strip()
-    .replace("tags/", "")
-)
-# when invoking pyinstaller from the project root, this gets run from the project root.
-with open("./capa/version.py", "r", encoding="utf-8") as f:
-    lines = f.read()
-# version.py contains the version string and other helper functions
-# here we manually replace the version value substring with the result of the above git output
-VERSION_DEF = "__version__ = "
-s = lines.index(VERSION_DEF)
-e = s + len(VERSION_DEF)
-off_rest_file = e + lines[e:].index("\n")
-lines = lines[s:e] + f'"{version}"' + lines[off_rest_file:]
-with open("./capa/version.py", "w", encoding="utf-8") as f:
-    f.write(lines)
-
 a = Analysis(
     # when invoking pyinstaller from the project root,
     # this gets invoked from the directory of the spec file,
@@ -44,6 +19,7 @@ a = Analysis(
         # i.e. ./.github/pyinstaller
         ("../../rules", "rules"),
         ("../../sigs", "sigs"),
+        ("../../cache", "cache"),
         # capa.render.default uses tabulate that depends on wcwidth.
         # it seems wcwidth uses a json file `version.json`
         # and this doesn't get picked up by pyinstaller automatically.

.github/workflows/build.yml

@@ -19,21 +19,21 @@ jobs:
             # use old linux so that the shared library versioning is more portable
             artifact_name: capa
             asset_name: linux
-          - os: windows-2022
+          - os: windows-2019
             artifact_name: capa.exe
             asset_name: windows
-          - os: macos-10.15
+          - os: macos-11
             # use older macOS for assumed better portability
             artifact_name: capa
             asset_name: macos
     steps:
       - name: Checkout capa
-        uses: actions/checkout@v2
+        uses: actions/checkout@ac593985615ec2ede58e132d2e21d2b1cbd6127c # v3.3.0
         with:
           submodules: true
       # using Python 3.8 to support running across multiple operating systems including Windows 7
       - name: Set up Python 3.8
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@d27e3f3d7c64b4bbf8e4abfb9b63b83e846e0435 # v4.5.0
         with:
           python-version: 3.8
       - if: matrix.os == 'ubuntu-18.04'
@@ -42,6 +42,8 @@ jobs:
         run: python -m pip install --upgrade pip setuptools
       - name: Install capa with build requirements
         run: pip install -e .[build]
+      - name: Cache the rule set
+        run: python ./scripts/cache-ruleset.py ./rules/ ./cache/
       - name: Build standalone executable
         run: pyinstaller --log-level DEBUG .github/pyinstaller/pyinstaller.spec
       - name: Does it run (PE)?
@@ -50,7 +52,7 @@ jobs:
         run: dist/capa "tests/data/499c2a85f6e8142c3f48d4251c9c7cd6.raw32"
       - name: Does it run (ELF)?
         run: dist/capa "tests/data/7351f8a40c5450557b24622417fc478d.elf_"
-      - uses: actions/upload-artifact@v2
+      - uses: actions/upload-artifact@0b7f8abb1508181956e8e162db84b466c27e18ce # v3.1.2
         with:
           name: ${{ matrix.asset_name }}
           path: dist/${{ matrix.artifact_name }}
@@ -74,11 +76,11 @@ jobs:
             asset_name: windows
     steps:
       - name: Download ${{ matrix.asset_name }}
-        uses: actions/download-artifact@v2
+        uses: actions/download-artifact@9bc31d5ccc31df68ecc42ccf4149144866c47d8a # v3.0.2
         with:
           name: ${{ matrix.asset_name }}
       - name: Set executable flag
-        if: matrix.os != 'windows-2022'      
+        if: matrix.os != 'windows-2022'
         run: chmod +x ${{ matrix.artifact_name }}
       - name: Run capa
         run: ./${{ matrix.artifact_name }} -h
@@ -100,7 +102,7 @@ jobs:
             artifact_name: capa
     steps:
       - name: Download ${{ matrix.asset_name }}
-        uses: actions/download-artifact@v2
+        uses: actions/download-artifact@9bc31d5ccc31df68ecc42ccf4149144866c47d8a # v3.0.2
         with:
           name: ${{ matrix.asset_name }}
       - name: Set executable flag
@@ -110,7 +112,7 @@ jobs:
       - name: Zip ${{ matrix.artifact_name }} into ${{ env.zip_name }}
         run: zip ${{ env.zip_name }} ${{ matrix.artifact_name }}
       - name: Upload ${{ env.zip_name }} to GH Release
-        uses: svenstaro/upload-release-action@v2
+        uses: svenstaro/upload-release-action@2728235f7dc9ff598bd86ce3c274b74f802d2208 # v2
         with:
           repo_token: ${{ secrets.GITHUB_TOKEN}}
           file: ${{ env.zip_name }}

.github/workflows/changelog.yml

@@ -17,7 +17,7 @@ jobs:
     steps:
     - name: Get changed files
       id: files
-      uses: Ana06/get-changed-files@v1.2
+      uses: Ana06/get-changed-files@e0c398b7065a8d84700c471b6afc4116d1ba4e96 # v2.2.0
     - name: check changelog updated
       id: changelog_updated
       env:
@@ -27,14 +27,14 @@ jobs:
         echo $FILES | grep -qF 'CHANGELOG.md' || echo $PR_BODY | grep -qiF "$NO_CHANGELOG"
     - name: Reject pull request if no CHANGELOG update
       if: ${{ always() && steps.changelog_updated.outcome == 'failure' }}
-      uses: Ana06/automatic-pull-request-review@v0.1.0
+      uses: Ana06/automatic-pull-request-review@0cf4e8a17ba79344ed3fdd7fed6dd0311d08a9d4 # v0.1.0
       with:
         repo-token: ${{ secrets.GITHUB_TOKEN }}
         event: REQUEST_CHANGES
         body: "Please add bug fixes, new features, breaking changes and anything else you think is worthwhile mentioning to the `master (unreleased)` section of CHANGELOG.md. If no CHANGELOG update is needed add the following to the PR description: `${{ env.NO_CHANGELOG }}`"
         allow_duplicate: false
     - name: Dismiss previous review if CHANGELOG update
-      uses: Ana06/automatic-pull-request-review@v0.1.0
+      uses: Ana06/automatic-pull-request-review@0cf4e8a17ba79344ed3fdd7fed6dd0311d08a9d4 # v0.1.0
       with:
         repo-token: ${{ secrets.GITHUB_TOKEN }}
         event: DISMISS

.github/workflows/publish.yml

@@ -11,9 +11,9 @@ jobs:
   deploy:
     runs-on: ubuntu-20.04
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@ac593985615ec2ede58e132d2e21d2b1cbd6127c # v3.3.0
       - name: Set up Python
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@d27e3f3d7c64b4bbf8e4abfb9b63b83e846e0435 # v4.5.0
         with:
           python-version: '3.7'
       - name: Install dependencies
@@ -27,4 +27,3 @@ jobs:
         run: |
           python setup.py sdist bdist_wheel
           twine upload --skip-existing dist/*
-

.github/workflows/scorecard.yml

@@ -0,0 +1,72 @@
+# This workflow uses actions that are not certified by GitHub. They are provided
+# by a third-party and are governed by separate terms of service, privacy
+# policy, and support documentation.
+
+name: Scorecard supply-chain security
+on:
+  # For Branch-Protection check. Only the default branch is supported. See
+  # https://github.com/ossf/scorecard/blob/main/docs/checks.md#branch-protection
+  branch_protection_rule:
+  # To guarantee Maintained check is occasionally updated. See
+  # https://github.com/ossf/scorecard/blob/main/docs/checks.md#maintained
+  schedule:
+    - cron: '43 4 * * 3'
+  push:
+    branches: [ "master" ]
+
+# Declare default permissions as read only.
+permissions: read-all
+
+jobs:
+  analysis:
+    name: Scorecard analysis
+    runs-on: ubuntu-latest
+    permissions:
+      # Needed to upload the results to code-scanning dashboard.
+      security-events: write
+      # Needed to publish results and get a badge (see publish_results below).
+      id-token: write
+      # Uncomment the permissions below if installing in a private repository.
+      # contents: read
+      # actions: read
+
+    steps:
+      - name: "Checkout code"
+        uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
+        with:
+          persist-credentials: false
+
+      - name: "Run analysis"
+        uses: ossf/scorecard-action@99c53751e09b9529366343771cc321ec74e9bd3d # v2.0.6
+        with:
+          results_file: results.sarif
+          results_format: sarif
+          # (Optional) "write" PAT token. Uncomment the `repo_token` line below if:
+          # - you want to enable the Branch-Protection check on a *public* repository, or
+          # - you are installing Scorecard on a *private* repository
+          # To create the PAT, follow the steps in https://github.com/ossf/scorecard-action#authentication-with-pat.
+          # repo_token: ${{ secrets.SCORECARD_TOKEN }}
+
+          # Public repositories:
+          #   - Publish results to OpenSSF REST API for easy access by consumers
+          #   - Allows the repository to include the Scorecard badge.
+          #   - See https://github.com/ossf/scorecard-action#publishing-results.
+          # For private repositories:
+          #   - `publish_results` will always be set to `false`, regardless
+          #     of the value entered here.
+          publish_results: true
+
+      # Upload the results as artifacts (optional). Commenting out will disable uploads of run results in SARIF
+      # format to the repository Actions tab.
+      - name: "Upload artifact"
+        uses: actions/upload-artifact@3cea5372237819ed00197afe530f5a7ea3e805c8 # v3.1.0
+        with:
+          name: SARIF file
+          path: results.sarif
+          retention-days: 5
+
+      # Upload the results to GitHub's code scanning dashboard.
+      - name: "Upload to code-scanning"
+        uses: github/codeql-action/upload-sarif@807578363a7869ca324a79039e6db9c843e0e100 # v2.1.27
+        with:
+          sarif_file: results.sarif

.github/workflows/tag.yml

@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-20.04
     steps:
     - name: Checkout capa-rules
-      uses: actions/checkout@v2
+      uses: actions/checkout@ac593985615ec2ede58e132d2e21d2b1cbd6127c # v3.3.0
       with:
         repository: mandiant/capa-rules
         token: ${{ secrets.CAPA_TOKEN }}
@@ -23,7 +23,7 @@ jobs:
         git tag $name -m "https://github.com/mandiant/capa/releases/$name"
         # TODO update branch name-major=${name%%.*}
     - name: Push tag to capa-rules
-      uses: ad-m/github-push-action@master
+      uses: ad-m/github-push-action@0fafdd62b84042d49ec0cb92d9cac7f7ce4ec79e # master
       with:
         repository: mandiant/capa-rules
         github_token: ${{ secrets.CAPA_TOKEN }}

.github/workflows/tests.yml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-20.04
     steps:
     - name: Checkout capa
-      uses: actions/checkout@v2
+      uses: actions/checkout@ac593985615ec2ede58e132d2e21d2b1cbd6127c # v3.3.0
     # The sync GH action in capa-rules relies on a single '- *$' in the CHANGELOG file
     - name: Ensure CHANGELOG has '- *$'
       run: |
@@ -26,9 +26,9 @@ jobs:
     runs-on: ubuntu-20.04
     steps:
     - name: Checkout capa
-      uses: actions/checkout@v2
+      uses: actions/checkout@ac593985615ec2ede58e132d2e21d2b1cbd6127c # v3.3.0
     - name: Set up Python 3.8
-      uses: actions/setup-python@v2
+      uses: actions/setup-python@d27e3f3d7c64b4bbf8e4abfb9b63b83e846e0435 # v4.5.0
       with:
         python-version: "3.8"
     - name: Install dependencies
@@ -40,17 +40,17 @@ jobs:
     - name: Lint with pycodestyle
       run: pycodestyle --show-source capa/ scripts/ tests/
     - name: Check types with mypy
-      run: mypy --config-file .github/mypy/mypy.ini capa/ scripts/ tests/
+      run: mypy --config-file .github/mypy/mypy.ini --check-untyped-defs capa/ scripts/ tests/
 
   rule_linter:
     runs-on: ubuntu-20.04
     steps:
     - name: Checkout capa with submodules
-      uses: actions/checkout@v2
+      uses: actions/checkout@ac593985615ec2ede58e132d2e21d2b1cbd6127c # v3.3.0
       with:
         submodules: recursive
     - name: Set up Python 3.8
-      uses: actions/setup-python@v2
+      uses: actions/setup-python@d27e3f3d7c64b4bbf8e4abfb9b63b83e846e0435 # v4.5.0
       with:
         python-version: "3.8"
     - name: Install capa
@@ -67,7 +67,7 @@ jobs:
       matrix:
         os: [ubuntu-20.04, windows-2019, macos-11]
         # across all operating systems
-        python-version: ["3.7", "3.10"]
+        python-version: ["3.7", "3.11"]
         include:
           # on Ubuntu run these as well
           - os: ubuntu-20.04
@@ -76,11 +76,11 @@ jobs:
             python-version: "3.9"
     steps:
     - name: Checkout capa with submodules
-      uses: actions/checkout@v2
+      uses: actions/checkout@ac593985615ec2ede58e132d2e21d2b1cbd6127c # v3.3.0
       with:
         submodules: recursive
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v2
+      uses: actions/setup-python@d27e3f3d7c64b4bbf8e4abfb9b63b83e846e0435 # v4.5.0
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install pyyaml

CHANGELOG.md

@@ -3,23 +3,174 @@
 ## master (unreleased)
 
 ### New Features
+- dotnet: add support for basic blocks #1326 @mike-hunhoff
 
 ### Breaking Changes
 
-### New Rules (0)
+### New Rules (9)
 
-- 
+- persistence/scheduled-tasks/schedule-task-via-at joren485
+- data-manipulation/prng/generate-random-numbers-via-rtlgenrandom william.ballenthin@mandiant.com
+- communication/ip/convert-ip-address-from-string @mr-tz
+- data-manipulation/compression/compress-data-via-zlib-inflate-or-deflate blas.kojusner@mandiant.com
+- executable/installer/dotnet/packaged-as-single-file-dotnet-application michael.hunhoff@mandiant.com
+- communication/socket/create-raw-socket blas.kojusner@mandiant.com
+- communication/http/reference-http-user-agent-string @mr-tz
+- communication/http/get-http-content-length william.ballenthin@mandiant.com
+- nursery/move-directory michael.hunhoff@mandiant.com
+-
 
 ### Bug Fixes
-
+- extractor: fix vivisect loop detection corner case #1310 @mr-tz
 
 ### capa explorer IDA Pro plugin
 
 ### Development
 
 ### Raw diffs
-- [capa v4.0.1...master](https://github.com/mandiant/capa/compare/v4.0.1...master)
-- [capa-rules v4.0.1...master](https://github.com/mandiant/capa-rules/compare/v4.0.1...master)
+- [capa v5.0.0...master](https://github.com/mandiant/capa/compare/v5.0.0...master)
+- [capa-rules v5.0.0...master](https://github.com/mandiant/capa-rules/compare/v5.0.0...master)
+
+
+## v5.0.0 (2023-02-08)
+This capa version comes with major improvements and additions to better handle .NET binaries. To showcase this we've updated and added over 30 .NET rules.  
+
+Additionally, capa now caches its rule set for better performance. The capa explorer also caches its analysis results, so that multiple IDA Pro or plugin invocations don't need to repeat the same analysis.
+
+We have removed the SMDA backend and changed the program return codes to be positive numbers.
+
+Other improvements to highlight include better ELF OS detection, various rendering bug fixes, and enhancements to the feature extraction. We've also added support for Python 3.11.
+
+Thanks for all the support, especially to @jsoref, @bkojusner, @edeca, @richardweiss80, @joren485, @ryantxu1, @mwilliams31, @anushkavirgaonkar, @MalwareMechanic, @Still34, @dzbeck, @johnk3r, and everyone else who submitted bugs and provided feedback!
+
+### New Features
+- verify rule metadata format on load #1160 @mr-tz
+- dotnet: emit property features #1168 @anushkavirgaonkar
+- dotnet: emit API features for objects created via the newobj instruction #1186 @mike-hunhoff
+- dotnet: emit API features for generic methods #1231 @mike-hunhoff
+- Python 3.11 support #1192 @williballenthin
+- dotnet: emit calls to/from MethodDef methods #1236 @mike-hunhoff
+- dotnet: emit namespace/class features for ldvirtftn/ldftn instructions #1241 @mike-hunhoff
+- dotnet: emit namespace/class features for type references #1242 @mike-hunhoff
+- dotnet: extract dotnet and pe format #1187 @mr-tz
+- don't render all library rule matches in vverbose output #1174 @mr-tz
+- cache the rule set across invocations for better performance #1212 @williballenthin
+- update ATT&CK/MBC data for linting #1297 @mr-tz
+
+### Breaking Changes
+- remove SMDA backend #1062 @williballenthin
+- error return codes are now positive numbers #1269 @mr-tz
+
+### New Rules (77)
+
+- collection/use-dotnet-library-sharpclipboard @johnk3r
+- data-manipulation/encryption/aes/use-dotnet-library-encryptdecryptutils @johnk3r
+- data-manipulation/json/use-dotnet-library-newtonsoftjson @johnk3r
+- data-manipulation/svg/use-dotnet-library-sharpvectors @johnk3r
+- executable/resource/embed-dependencies-as-resources-using-fodycostura @johnk3r @mr-tz
+- communication/ftp/send/send-file-using-ftp michael.hunhof@mandiant.com anushka.virgaonkar@mandiant.com
+- nursery/extract-zip-archive anushka.virgaonkar@mandiant.com
+- nursery/allocate-unmanaged-memory-in-dotnet michael.hunhoff@mandiant.com
+- nursery/check-file-extension-in-dotnet michael.hunhoff@mandiant.com
+- nursery/decode-data-using-base64-in-dotnet michael.hunhoff@mandiant.com
+- nursery/deserialize-json-in-dotnet michael.hunhoff@mandiant.com
+- nursery/find-data-using-regex-in-dotnet michael.hunhoff@mandiant.com
+- nursery/generate-random-filename-in-dotnet michael.hunhoff@mandiant.com
+- nursery/get-os-version-in-dotnet michael.hunhoff@mandiant.com
+- nursery/load-xml-in-dotnet michael.hunhoff@mandiant.com
+- nursery/manipulate-unmanaged-memory-in-dotnet michael.hunhoff@mandiant.com
+- nursery/save-image-in-dotnet michael.hunhoff@mandiant.com
+- nursery/send-email-in-dotnet michael.hunhoff@mandiant.com
+- nursery/serialize-json-in-dotnet michael.hunhoff@mandiant.com
+- nursery/set-http-user-agent-in-dotnet michael.hunhoff@mandiant.com
+- nursery/compile-csharp-in-dotnet michael.hunhoff@mandiant.com
+- nursery/compile-visual-basic-in-dotnet michael.hunhoff@mandiant.com
+- nursery/compress-data-using-gzip-in-dotnet michael.hunhoff@mandiant.com
+- nursery/execute-sqlite-statement-in-dotnet michael.hunhoff@mandiant.com
+- nursery/execute-via-asynchronous-task-in-dotnet michael.hunhoff@mandiant.com
+- nursery/execute-via-timer-in-dotnet michael.hunhoff@mandiant.com
+- nursery/execute-wmi-query-in-dotnet michael.hunhoff@mandiant.com
+- nursery/manipulate-network-credentials-in-dotnet michael.hunhoff@mandiant.com
+- nursery/encrypt-data-using-aes william.ballenthin@mandiant.com Ivan Kwiatkowski (@JusticeRage)
+- host-interaction/uac/bypass/bypass-uac-via-rpc david.cannings@pwc.com david@edeca.net
+- nursery/check-for-vm-using-instruction-vpcext richard.weiss@mandiant.com
+- nursery/get-windows-directory-from-kuser_shared_data david.cannings@pwc.com
+- nursery/encrypt-data-using-openssl-dsa Ana06
+- nursery/encrypt-data-using-openssl-ecdsa Ana06
+- nursery/encrypt-data-using-openssl-rsa Ana06
+- runtime/dotnet/execute-via-dotnet-startup-hook william.ballenthin@mandiant.com
+- host-interaction/console/manipulate-console-buffer william.ballenthin@mandiant.com michael.hunhoff@mandiant.com
+- nursery/access-wmi-data-in-dotnet michael.hunhoff@mandiant.com
+- nursery/allocate-unmanaged-memory-via-dotnet michael.hunhoff@mandiant.com
+- nursery/generate-random-bytes-in-dotnet michael.hunhoff@mandiant.com
+- nursery/manipulate-console-window michael.hunhoff@mandiant.com
+- nursery/obfuscated-with-koivm michael.hunhoff@mandiant.com
+- nursery/implement-com-dll moritz.raabe@mandiant.com
+- nursery/linked-against-libsodium @mr-tz
+- compiler/nuitka/compiled-with-nuitka @williballenthin
+- nursery/authenticate-data-with-md5-mac william.ballenthin@mandiant.com
+- nursery/resolve-function-by-djb2-hash still@teamt5.org
+- host-interaction/mutex/create-semaphore-on-linux @ramen0x3f
+- host-interaction/mutex/lock-semaphore-on-linux @ramen0x3f
+- host-interaction/mutex/unlock-semaphore-on-linux @ramen0x3f
+- data-manipulation/hashing/sha384/hash-data-using-sha384 william.ballenthin@mandiant.com
+- data-manipulation/hashing/sha512/hash-data-using-sha512 william.ballenthin@mandiant.com
+- nursery/decode-data-using-url-encoding michael.hunhoff@mandiant.com
+- nursery/manipulate-user-privileges michael.hunhoff@mandiant.com
+- lib/get-os-version @mr-tz
+- nursery/decrypt-data-using-tea william.ballenthin@mandiant.com
+- nursery/encrypt-data-using-tea william.ballenthin@mandiant.com
+- nursery/hash-data-using-whirlpool william.ballenthin@mandiant.com
+- nursery/reference-base58-string william.ballenthin@mandiant.com
+- communication/mailslot/create-mailslot william.ballenthin@mandiant.com
+- executable/resource/access-dotnet-resource @mr-tz
+- linking/static/linked-against-cpp-standard-library @mr-tz
+- data-manipulation/compression/compress-data-using-lzo david@edeca.net david.cannings@pwc.com
+- data-manipulation/compression/decompress-data-using-lzo david@edeca.net david.cannings@pwc.com
+- communication/socket/tcp/create-tcp-socket-via-raw-afd-driver william.ballenthin@mandiant.com
+- host-interaction/process/map-section-object william.ballenthin@mandiant.com
+- lib/create-or-open-section-object william.ballenthin@mandiant.com
+- load-code/dotnet/execute-dotnet-assembly-via-clr-host blas.kojusner@mandiant.com
+- load-code/execute-vbscript-javascript-or-jscript-in-memory blas.kojusner@mandiant.com
+- host-interaction/file-system/reference-absolute-stream-path-on-windows blas.kojusner@mandiant.com
+- nursery/generate-method-via-reflection-in-dotnet michael.hunhoff@mandiant.com
+- nursery/unmanaged-call-via-dynamic-pinvoke-in-dotnet michael.hunhoff@mandiant.com
+
+### Bug Fixes
+- render: convert feature attributes to aliased dictionary for vverbose #1152 @mike-hunhoff
+- decouple Token dependency / extractor and features #1139 @mr-tz
+- update pydantic model to guarantee type coercion #1176 @mike-hunhoff
+- do not overwrite version in version.py during PyInstaller build #1169 @mr-tz
+- render: fix vverbose rendering of offsets #1215 @williballenthin
+- elf: better detect OS via GLIBC ABI version needed and dependencies #1221 @williballenthin
+- dotnet: address unhandled exceptions with improved type checking #1230 @mike-hunhoff
+- fix import-to-ida script formatting #1208 @williballenthin
+- render: fix verbose rendering of scopes #1263 @williballenthin
+- rules: better detect invalid rules #1282 @williballenthin
+- show-features: better render strings with embedded whitespace #1267 @williballenthin
+- handle vivisect bug around strings at instruction level, use min length 4 #1271 @williballenthin @mr-tz
+- extractor: guard against invalid "calls from" features #1177 @mr-tz
+- extractor: add format to global features #1258 @mr-tz
+- extractor: discover all strings with length >= 4 #1280 @mr-tz
+- extractor: don't extract byte features for strings #1293 @mr-tz
+
+### capa explorer IDA Pro plugin
+- fix: display instruction items #1154 @mr-tz
+- fix: accept only plaintext pasted content #1194 @williballenthin
+- fix: UnboundLocalError #1217 @williballenthin
+- extractor: add support for COFF files and extern functions #1223 @mike-hunhoff
+- doc: improve error messaging and documentation related to capa rule set #1249 @mike-hunhoff
+- fix: assume 32-bit displacement for offsets #1250 @mike-hunhoff
+- generator: refactor caching and matching #1251 @mike-hunhoff
+- fix: improve exception handling to prevent IDA from locking up when errors occur #1262 @mike-hunhoff
+- verify rule metadata using Pydantic #1167 @mr-tz
+- extractor: make read consistent with file object behavior #1254 @mr-tz
+- fix: UnboundLocalError x2 #1302 @mike-hunhoff
+- cache capa results across IDA sessions #1279 @mr-tz
+
+### Raw diffs
+- [capa v4.0.1...v5.0.0](https://github.com/mandiant/capa/compare/v4.0.1...v5.0.0)
+- [capa-rules v4.0.1...v5.0.0](https://github.com/mandiant/capa-rules/compare/v4.0.1...v5.0.0)
 
 
 ## v4.0.1 (2022-08-15)
@@ -1245,7 +1396,7 @@ Download a standalone binary below and checkout the readme [here on GitHub](http
   - setup: pin vivisect version @williballenthin
   - setup: bump vivisect dependency version @williballenthin
   - setup: set Python project name to `flare-capa` @williballenthin
-  - ci: run tests and linter via Github Actions @Ana06
+  - ci: run tests and linter via GitHub Actions @Ana06
   - hooks: run style checkers and hide stashed output @Ana06
   - linter: ignore period in rule filename @williballenthin
   - linter: warn on nursery rule with no changes needed @williballenthin

README.md

@@ -2,7 +2,7 @@
 
 [![PyPI - Python Version](https://img.shields.io/pypi/pyversions/flare-capa)](https://pypi.org/project/flare-capa)
 [![Last release](https://img.shields.io/github/v/release/mandiant/capa)](https://github.com/mandiant/capa/releases)
-[![Number of rules](https://img.shields.io/badge/rules-703-blue.svg)](https://github.com/mandiant/capa-rules)
+[![Number of rules](https://img.shields.io/badge/rules-779-blue.svg)](https://github.com/mandiant/capa-rules)
 [![CI status](https://github.com/mandiant/capa/workflows/CI/badge.svg)](https://github.com/mandiant/capa/actions?query=workflow%3ACI+event%3Apush+branch%3Amaster)
 [![Downloads](https://img.shields.io/github/downloads/mandiant/capa/total)](https://github.com/mandiant/capa/releases)
 [![License](https://img.shields.io/badge/license-Apache--2.0-green.svg)](LICENSE.txt)

capa/engine.py

@@ -8,7 +8,7 @@
 
 import copy
 import collections
-from typing import TYPE_CHECKING, Set, Dict, List, Tuple, Mapping, Iterable
+from typing import TYPE_CHECKING, Set, Dict, List, Tuple, Union, Mapping, Iterable, Iterator, cast
 
 import capa.perf
 import capa.features.common
@@ -38,7 +38,7 @@ class Statement:
     """
 
     def __init__(self, description=None):
-        super(Statement, self).__init__()
+        super().__init__()
         self.name = self.__class__.__name__
         self.description = description
 
@@ -60,17 +60,24 @@ class Statement:
         """
         raise NotImplementedError()
 
-    def get_children(self):
+    def get_children(self) -> Iterator[Union["Statement", Feature]]:
         if hasattr(self, "child"):
-            yield self.child
+            # this really confuses mypy because the property may not exist
+            # since its defined in the subclasses.
+            child = self.child  # type: ignore
+            assert isinstance(child, (Statement, Feature))
+            yield child
 
         if hasattr(self, "children"):
             for child in getattr(self, "children"):
+                assert isinstance(child, (Statement, Feature))
                 yield child
 
     def replace_child(self, existing, new):
         if hasattr(self, "child"):
-            if self.child is existing:
+            # this really confuses mypy because the property may not exist
+            # since its defined in the subclasses.
+            if self.child is existing:  # type: ignore
                 self.child = new
 
         if hasattr(self, "children"):
@@ -90,7 +97,7 @@ class And(Statement):
     """
 
     def __init__(self, children, description=None):
-        super(And, self).__init__(description=description)
+        super().__init__(description=description)
         self.children = children
 
     def evaluate(self, ctx, short_circuit=True):
@@ -123,7 +130,7 @@ class Or(Statement):
     """
 
     def __init__(self, children, description=None):
-        super(Or, self).__init__(description=description)
+        super().__init__(description=description)
         self.children = children
 
     def evaluate(self, ctx, short_circuit=True):
@@ -150,7 +157,7 @@ class Not(Statement):
     """match only if the child evaluates to False."""
 
     def __init__(self, child, description=None):
-        super(Not, self).__init__(description=description)
+        super().__init__(description=description)
         self.child = child
 
     def evaluate(self, ctx, short_circuit=True):
@@ -172,7 +179,7 @@ class Some(Statement):
     """
 
     def __init__(self, count, children, description=None):
-        super(Some, self).__init__(description=description)
+        super().__init__(description=description)
         self.count = count
         self.children = children
 
@@ -208,7 +215,7 @@ class Range(Statement):
     """match if the child is contained in the ctx set with a count in the given range."""
 
     def __init__(self, child, min=None, max=None, description=None):
-        super(Range, self).__init__(description=description)
+        super().__init__(description=description)
         self.child = child
         self.min = min if min is not None else 0
         self.max = max if max is not None else (1 << 64 - 1)
@@ -237,7 +244,7 @@ class Subscope(Statement):
     """
 
     def __init__(self, scope, child, description=None):
-        super(Subscope, self).__init__(description=description)
+        super().__init__(description=description)
         self.scope = scope
         self.child = child
 

capa/features/address.py

@@ -1,7 +1,5 @@
 import abc
 
-from dncil.clr.token import Token
-
 
 class Address(abc.ABC):
     @abc.abstractmethod
@@ -34,6 +32,9 @@ class AbsoluteVirtualAddress(int, Address):
     def __repr__(self):
         return f"absolute(0x{self:x})"
 
+    def __hash__(self):
+        return int.__hash__(self)
+
 
 class RelativeVirtualAddress(int, Address):
     """a memory address relative to a base address"""
@@ -41,6 +42,9 @@ class RelativeVirtualAddress(int, Address):
     def __repr__(self):
         return f"relative(0x{self:x})"
 
+    def __hash__(self):
+        return int.__hash__(self)
+
 
 class FileOffsetAddress(int, Address):
     """an address relative to the start of a file"""
@@ -52,52 +56,45 @@ class FileOffsetAddress(int, Address):
     def __repr__(self):
         return f"file(0x{self:x})"
 
+    def __hash__(self):
+        return int.__hash__(self)
 
-class DNTokenAddress(Address):
+
+class DNTokenAddress(int, Address):
     """a .NET token"""
 
-    def __init__(self, token: Token):
-        self.token = token
-
-    def __eq__(self, other):
-        return self.token.value == other.token.value
-
-    def __lt__(self, other):
-        return self.token.value < other.token.value
-
-    def __hash__(self):
-        return hash(self.token.value)
+    def __new__(cls, token: int):
+        return int.__new__(cls, token)
 
     def __repr__(self):
-        return f"token(0x{self.token.value:x})"
+        return f"token(0x{self:x})"
 
-    def __index__(self):
-        # returns the object converted to an integer
-        return self.token.value
+    def __hash__(self):
+        return int.__hash__(self)
 
 
 class DNTokenOffsetAddress(Address):
     """an offset into an object specified by a .NET token"""
 
-    def __init__(self, token: Token, offset: int):
+    def __init__(self, token: int, offset: int):
         assert offset >= 0
         self.token = token
         self.offset = offset
 
     def __eq__(self, other):
-        return (self.token.value, self.offset) == (other.token.value, other.offset)
+        return (self.token, self.offset) == (other.token, other.offset)
 
     def __lt__(self, other):
-        return (self.token.value, self.offset) < (other.token.value, other.offset)
+        return (self.token, self.offset) < (other.token, other.offset)
 
     def __hash__(self):
-        return hash((self.token.value, self.offset))
+        return hash((self.token, self.offset))
 
     def __repr__(self):
-        return f"token(0x{self.token.value:x})+(0x{self.offset:x})"
+        return f"token(0x{self.token:x})+(0x{self.offset:x})"
 
     def __index__(self):
-        return self.token.value + self.offset
+        return self.token + self.offset
 
 
 class _NoAddress(Address):

capa/features/basicblock.py

@@ -11,7 +11,7 @@ from capa.features.common import Feature
 
 class BasicBlock(Feature):
     def __init__(self, description=None):
-        super(BasicBlock, self).__init__(None, description=description)
+        super().__init__(0, description=description)
 
     def __str__(self):
         return "basic block"

capa/features/common.py

@@ -9,9 +9,10 @@
 import re
 import abc
 import codecs
+import typing
 import logging
 import collections
-from typing import TYPE_CHECKING, Set, Dict, List, Union, Optional, Sequence
+from typing import TYPE_CHECKING, Set, Dict, List, Union, Optional
 
 if TYPE_CHECKING:
     # circular import, otherwise
@@ -29,6 +30,14 @@ MAX_BYTES_FEATURE_SIZE = 0x100
 THUNK_CHAIN_DEPTH_DELTA = 5
 
 
+class FeatureAccess:
+    READ = "read"
+    WRITE = "write"
+
+
+VALID_FEATURE_ACCESS = (FeatureAccess.READ, FeatureAccess.WRITE)
+
+
 def bytes_to_str(b: bytes) -> str:
     return str(codecs.encode(b, "hex").decode("utf-8"))
 
@@ -73,7 +82,7 @@ class Result:
         children: List["Result"],
         locations: Optional[Set[Address]] = None,
     ):
-        super(Result, self).__init__()
+        super().__init__()
         self.success = success
         self.statement = statement
         self.children = children
@@ -92,15 +101,19 @@ class Result:
 
 
 class Feature(abc.ABC):
-    def __init__(self, value: Union[str, int, float, bytes], description=None):
+    def __init__(
+        self,
+        value: Union[str, int, float, bytes],
+        description: Optional[str] = None,
+    ):
         """
         Args:
           value (any): the value of the feature, such as the number or string.
           description (str): a human-readable description that explains the feature value.
         """
-        super(Feature, self).__init__()
-        self.name = self.__class__.__name__.lower()
+        super().__init__()
 
+        self.name = self.__class__.__name__.lower()
         self.value = value
         self.description = description
 
@@ -119,23 +132,28 @@ class Feature(abc.ABC):
             < capa.features.freeze.features.feature_from_capa(other).json()
         )
 
+    def get_name_str(self) -> str:
+        """
+        render the name of this feature, for use by `__str__` and friends.
+        subclasses should override to customize the rendering.
+        """
+        return self.name
+
     def get_value_str(self) -> str:
         """
         render the value of this feature, for use by `__str__` and friends.
         subclasses should override to customize the rendering.
-
-        Returns: any
         """
         return str(self.value)
 
     def __str__(self):
         if self.value is not None:
             if self.description:
-                return "%s(%s = %s)" % (self.name, self.get_value_str(), self.description)
+                return "%s(%s = %s)" % (self.get_name_str(), self.get_value_str(), self.description)
             else:
-                return "%s(%s)" % (self.name, self.get_value_str())
+                return "%s(%s)" % (self.get_name_str(), self.get_value_str())
         else:
-            return "%s" % self.name
+            return "%s" % self.get_name_str()
 
     def __repr__(self):
         return str(self)
@@ -148,33 +166,37 @@ class Feature(abc.ABC):
 
 class MatchedRule(Feature):
     def __init__(self, value: str, description=None):
-        super(MatchedRule, self).__init__(value, description=description)
+        super().__init__(value, description=description)
         self.name = "match"
 
 
 class Characteristic(Feature):
     def __init__(self, value: str, description=None):
-        super(Characteristic, self).__init__(value, description=description)
+        super().__init__(value, description=description)
 
 
 class String(Feature):
     def __init__(self, value: str, description=None):
-        super(String, self).__init__(value, description=description)
+        super().__init__(value, description=description)
+
+    def get_value_str(self) -> str:
+        assert isinstance(self.value, str)
+        return escape_string(self.value)
 
 
 class Class(Feature):
     def __init__(self, value: str, description=None):
-        super(Class, self).__init__(value, description=description)
+        super().__init__(value, description=description)
 
 
 class Namespace(Feature):
     def __init__(self, value: str, description=None):
-        super(Namespace, self).__init__(value, description=description)
+        super().__init__(value, description=description)
 
 
 class Substring(String):
     def __init__(self, value: str, description=None):
-        super(Substring, self).__init__(value, description=description)
+        super().__init__(value, description=description)
         self.value = value
 
     def evaluate(self, ctx, short_circuit=True):
@@ -183,8 +205,9 @@ class Substring(String):
 
         # mapping from string value to list of locations.
         # will unique the locations later on.
-        matches = collections.defaultdict(list)
+        matches: typing.DefaultDict[str, Set[Address]] = collections.defaultdict(set)
 
+        assert isinstance(self.value, str)
         for feature, locations in ctx.items():
             if not isinstance(feature, (String,)):
                 continue
@@ -194,32 +217,32 @@ class Substring(String):
                 raise ValueError("unexpected feature value type")
 
             if self.value in feature.value:
-                matches[feature.value].extend(locations)
+                matches[feature.value].update(locations)
                 if short_circuit:
                     # we found one matching string, thats sufficient to match.
                     # don't collect other matching strings in this mode.
                     break
 
         if matches:
-            # finalize: defaultdict -> dict
-            # which makes json serialization easier
-            matches = dict(matches)
-
             # collect all locations
             locations = set()
-            for s in matches.keys():
-                matches[s] = list(set(matches[s]))
-                locations.update(matches[s])
+            for locs in matches.values():
+                locations.update(locs)
 
             # unlike other features, we cannot return put a reference to `self` directly in a `Result`.
             # this is because `self` may match on many strings, so we can't stuff the matched value into it.
             # instead, return a new instance that has a reference to both the substring and the matched values.
-            return Result(True, _MatchedSubstring(self, matches), [], locations=locations)
+            return Result(True, _MatchedSubstring(self, dict(matches)), [], locations=locations)
         else:
             return Result(False, _MatchedSubstring(self, {}), [])
 
+    def get_value_str(self) -> str:
+        assert isinstance(self.value, str)
+        return escape_string(self.value)
+
     def __str__(self):
-        return "substring(%s)" % self.value
+        assert isinstance(self.value, str)
+        return "substring(%s)" % escape_string(self.value)
 
 
 class _MatchedSubstring(Substring):
@@ -236,7 +259,7 @@ class _MatchedSubstring(Substring):
           substring: the substring feature that matches.
           match: mapping from matching string to its locations.
         """
-        super(_MatchedSubstring, self).__init__(str(substring.value), description=substring.description)
+        super().__init__(str(substring.value), description=substring.description)
         # we want this to collide with the name of `Substring` above,
         # so that it works nicely with the renderers.
         self.name = "substring"
@@ -244,6 +267,7 @@ class _MatchedSubstring(Substring):
         self.matches = matches
 
     def __str__(self):
+        assert isinstance(self.value, str)
         return 'substring("%s", matches = %s)' % (
             self.value,
             ", ".join(map(lambda s: '"' + s + '"', (self.matches or {}).keys())),
@@ -252,7 +276,7 @@ class _MatchedSubstring(Substring):
 
 class Regex(String):
     def __init__(self, value: str, description=None):
-        super(Regex, self).__init__(value, description=description)
+        super().__init__(value, description=description)
         self.value = value
 
         pat = self.value[len("/") : -len("/")]
@@ -262,12 +286,12 @@ class Regex(String):
             flags |= re.IGNORECASE
         try:
             self.re = re.compile(pat, flags)
-        except re.error:
+        except re.error as exc:
             if value.endswith("/i"):
                 value = value[: -len("i")]
             raise ValueError(
                 "invalid regular expression: %s it should use Python syntax, try it at https://pythex.org" % value
-            )
+            ) from exc
 
     def evaluate(self, ctx, short_circuit=True):
         capa.perf.counters["evaluate.feature"] += 1
@@ -275,7 +299,7 @@ class Regex(String):
 
         # mapping from string value to list of locations.
         # will unique the locations later on.
-        matches = collections.defaultdict(list)
+        matches: typing.DefaultDict[str, Set[Address]] = collections.defaultdict(set)
 
         for feature, locations in ctx.items():
             if not isinstance(feature, (String,)):
@@ -290,32 +314,28 @@ class Regex(String):
             # using this mode cleans is more convenient for rule authors,
             # so that they don't have to prefix/suffix their terms like: /.*foo.*/.
             if self.re.search(feature.value):
-                matches[feature.value].extend(locations)
+                matches[feature.value].update(locations)
                 if short_circuit:
                     # we found one matching string, thats sufficient to match.
                     # don't collect other matching strings in this mode.
                     break
 
         if matches:
-            # finalize: defaultdict -> dict
-            # which makes json serialization easier
-            matches = dict(matches)
-
             # collect all locations
             locations = set()
-            for s in matches.keys():
-                matches[s] = list(set(matches[s]))
-                locations.update(matches[s])
+            for locs in matches.values():
+                locations.update(locs)
 
             # unlike other features, we cannot return put a reference to `self` directly in a `Result`.
             # this is because `self` may match on many strings, so we can't stuff the matched value into it.
             # instead, return a new instance that has a reference to both the regex and the matched values.
             # see #262.
-            return Result(True, _MatchedRegex(self, matches), [], locations=locations)
+            return Result(True, _MatchedRegex(self, dict(matches)), [], locations=locations)
         else:
             return Result(False, _MatchedRegex(self, {}), [])
 
     def __str__(self):
+        assert isinstance(self.value, str)
         return "regex(string =~ %s)" % self.value
 
 
@@ -333,7 +353,7 @@ class _MatchedRegex(Regex):
           regex: the regex feature that matches.
           matches: mapping from matching string to its locations.
         """
-        super(_MatchedRegex, self).__init__(str(regex.value), description=regex.description)
+        super().__init__(str(regex.value), description=regex.description)
         # we want this to collide with the name of `Regex` above,
         # so that it works nicely with the renderers.
         self.name = "regex"
@@ -341,6 +361,7 @@ class _MatchedRegex(Regex):
         self.matches = matches
 
     def __str__(self):
+        assert isinstance(self.value, str)
         return "regex(string =~ %s, matches = %s)" % (
             self.value,
             ", ".join(map(lambda s: '"' + s + '"', (self.matches or {}).keys())),
@@ -356,23 +377,26 @@ class StringFactory:
 
 class Bytes(Feature):
     def __init__(self, value: bytes, description=None):
-        super(Bytes, self).__init__(value, description=description)
+        super().__init__(value, description=description)
         self.value = value
 
     def evaluate(self, ctx, **kwargs):
         capa.perf.counters["evaluate.feature"] += 1
         capa.perf.counters["evaluate.feature.bytes"] += 1
 
+        assert isinstance(self.value, bytes)
         for feature, locations in ctx.items():
             if not isinstance(feature, (Bytes,)):
                 continue
 
+            assert isinstance(feature.value, bytes)
             if feature.value.startswith(self.value):
                 return Result(True, self, [], locations=locations)
 
         return Result(False, self, [])
 
     def get_value_str(self):
+        assert isinstance(self.value, bytes)
         return hex_string(bytes_to_str(self.value))
 
 
@@ -386,7 +410,7 @@ VALID_ARCH = (ARCH_I386, ARCH_AMD64, ARCH_ANY)
 
 class Arch(Feature):
     def __init__(self, value: str, description=None):
-        super(Arch, self).__init__(value, description=description)
+        super().__init__(value, description=description)
         self.name = "arch"
 
 
@@ -401,7 +425,7 @@ VALID_OS.update({OS_WINDOWS, OS_LINUX, OS_MACOS, OS_ANY})
 
 class OS(Feature):
     def __init__(self, value: str, description=None):
-        super(OS, self).__init__(value, description=description)
+        super().__init__(value, description=description)
         self.name = "os"
 
 
@@ -419,7 +443,7 @@ FORMAT_UNKNOWN = "unknown"
 
 class Format(Feature):
     def __init__(self, value: str, description=None):
-        super(Format, self).__init__(value, description=description)
+        super().__init__(value, description=description)
         self.name = "format"
 
 

capa/features/extractors/base_extractor.py

@@ -87,7 +87,7 @@ class FeatureExtractor:
         #  for example, the Vivisect feature extract might require the vw and/or path.
         # this base class doesn't know what to do with that info, though.
         #
-        super(FeatureExtractor, self).__init__()
+        super().__init__()
 
     @abc.abstractmethod
     def get_base_address(self) -> Union[AbsoluteVirtualAddress, capa.features.address._NoAddress]:

capa/features/extractors/common.py

@@ -9,6 +9,7 @@ import pefile
 import capa.features
 import capa.features.extractors.elf
 import capa.features.extractors.pefile
+import capa.features.extractors.strings
 from capa.features.common import OS, FORMAT_PE, FORMAT_ELF, OS_WINDOWS, FORMAT_FREEZE, Arch, Format, String, Feature
 from capa.features.freeze import is_freeze
 from capa.features.address import NO_ADDRESS, Address, FileOffsetAddress
@@ -63,7 +64,7 @@ def extract_arch(buf) -> Iterator[Tuple[Feature, Address]]:
         #  2. handling a new file format (e.g. macho)
         #
         # for (1) we can't do much - its shellcode and all bets are off.
-        # we could maybe accept a futher CLI argument to specify the arch,
+        # we could maybe accept a further CLI argument to specify the arch,
         # but i think this would be rarely used.
         # rules that rely on arch conditions will fail to match on shellcode.
         #
@@ -91,7 +92,7 @@ def extract_os(buf) -> Iterator[Tuple[Feature, Address]]:
         #  2. handling a new file format (e.g. macho)
         #
         # for (1) we can't do much - its shellcode and all bets are off.
-        # we could maybe accept a futher CLI argument to specify the OS,
+        # we could maybe accept a further CLI argument to specify the OS,
         # but i think this would be rarely used.
         # rules that rely on OS conditions will fail to match on shellcode.
         #

capa/features/extractors/dnfile/basicblock.py

@@ -0,0 +1,45 @@
+# Copyright (C) 2020 Mandiant, Inc. All Rights Reserved.
+# Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at: [package root]/LICENSE.txt
+# Unless required by applicable law or agreed to in writing, software distributed under the License
+#  is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and limitations under the License.
+
+from typing import Tuple, Iterator
+
+from dncil.cil.instruction import Instruction
+
+from capa.features.common import Feature, Characteristic
+from capa.features.address import Address
+from capa.features.basicblock import BasicBlock
+from capa.features.extractors.base_extractor import BBHandle, FunctionHandle
+
+
+def extract_bb_stackstring(fh: FunctionHandle, bbh: BBHandle) -> Iterator[Tuple[Feature, Address]]:
+    """extract stackstring indicators from basic block"""
+    raise NotImplementedError
+
+
+def extract_bb_tight_loop(fh: FunctionHandle, bbh: BBHandle) -> Iterator[Tuple[Feature, Address]]:
+    """extract tight loop indicators from a basic block"""
+    first: Instruction = bbh.inner.instructions[0]
+    last: Instruction = bbh.inner.instructions[-1]
+
+    if any((last.is_br(), last.is_cond_br(), last.is_leave())):
+        if last.operand == first.offset:
+            yield Characteristic("tight loop"), bbh.address
+
+
+def extract_features(fh: FunctionHandle, bbh: BBHandle) -> Iterator[Tuple[Feature, Address]]:
+    """extract basic block features"""
+    for bb_handler in BASIC_BLOCK_HANDLERS:
+        for feature, addr in bb_handler(fh, bbh):
+            yield feature, addr
+    yield BasicBlock(), bbh.address
+
+
+BASIC_BLOCK_HANDLERS = (
+    extract_bb_tight_loop,
+    # extract_bb_stackstring,
+)

capa/features/extractors/dnfile/extractor.py

@@ -8,27 +8,79 @@
 
 from __future__ import annotations
 
-from typing import List, Tuple, Iterator
+from typing import Set, Dict, List, Tuple, Union, Iterator, Optional
 
 import dnfile
-from dncil.clr.token import Token
+from dncil.cil.opcode import OpCodes
+from dncil.cil.instruction import Instruction
 
 import capa.features.extractors
+import capa.features.extractors.dotnetfile
 import capa.features.extractors.dnfile.file
 import capa.features.extractors.dnfile.insn
+import capa.features.extractors.dnfile.function
+import capa.features.extractors.dnfile.basicblock
 from capa.features.common import Feature
-from capa.features.address import NO_ADDRESS, Address, DNTokenAddress, DNTokenOffsetAddress, AbsoluteVirtualAddress
+from capa.features.address import NO_ADDRESS, Address, DNTokenAddress, DNTokenOffsetAddress
+from capa.features.extractors.dnfile.types import DnType, DnBasicBlock, DnUnmanagedMethod
 from capa.features.extractors.base_extractor import BBHandle, InsnHandle, FunctionHandle, FeatureExtractor
-from capa.features.extractors.dnfile.helpers import get_dotnet_managed_method_bodies
+from capa.features.extractors.dnfile.helpers import (
+    get_dotnet_types,
+    get_dotnet_fields,
+    get_dotnet_managed_imports,
+    get_dotnet_managed_methods,
+    get_dotnet_unmanaged_imports,
+    get_dotnet_managed_method_bodies,
+)
+
+
+class DnFileFeatureExtractorCache:
+    def __init__(self, pe: dnfile.dnPE):
+        self.imports: Dict[int, Union[DnType, DnUnmanagedMethod]] = {}
+        self.native_imports: Dict[int, Union[DnType, DnUnmanagedMethod]] = {}
+        self.methods: Dict[int, Union[DnType, DnUnmanagedMethod]] = {}
+        self.fields: Dict[int, Union[DnType, DnUnmanagedMethod]] = {}
+        self.types: Dict[int, Union[DnType, DnUnmanagedMethod]] = {}
+
+        for import_ in get_dotnet_managed_imports(pe):
+            self.imports[import_.token] = import_
+        for native_import in get_dotnet_unmanaged_imports(pe):
+            self.native_imports[native_import.token] = native_import
+        for method in get_dotnet_managed_methods(pe):
+            self.methods[method.token] = method
+        for field in get_dotnet_fields(pe):
+            self.fields[field.token] = field
+        for type_ in get_dotnet_types(pe):
+            self.types[type_.token] = type_
+
+    def get_import(self, token: int) -> Optional[Union[DnType, DnUnmanagedMethod]]:
+        return self.imports.get(token, None)
+
+    def get_native_import(self, token: int) -> Optional[Union[DnType, DnUnmanagedMethod]]:
+        return self.native_imports.get(token, None)
+
+    def get_method(self, token: int) -> Optional[Union[DnType, DnUnmanagedMethod]]:
+        return self.methods.get(token, None)
+
+    def get_field(self, token: int) -> Optional[Union[DnType, DnUnmanagedMethod]]:
+        return self.fields.get(token, None)
+
+    def get_type(self, token: int) -> Optional[Union[DnType, DnUnmanagedMethod]]:
+        return self.types.get(token, None)
 
 
 class DnfileFeatureExtractor(FeatureExtractor):
     def __init__(self, path: str):
-        super(DnfileFeatureExtractor, self).__init__()
+        super().__init__()
         self.pe: dnfile.dnPE = dnfile.dnPE(path)
 
+        # pre-compute .NET token lookup tables; each .NET method has access to this cache for feature extraction
+        # most relevant at instruction scope
+        self.token_cache: DnFileFeatureExtractorCache = DnFileFeatureExtractorCache(self.pe)
+
         # pre-compute these because we'll yield them at *every* scope.
         self.global_features: List[Tuple[Feature, Address]] = []
+        self.global_features.extend(capa.features.extractors.dotnetfile.extract_file_format())
         self.global_features.extend(capa.features.extractors.dotnetfile.extract_file_os(pe=self.pe))
         self.global_features.extend(capa.features.extractors.dotnetfile.extract_file_arch(pe=self.pe))
 
@@ -42,28 +94,140 @@ class DnfileFeatureExtractor(FeatureExtractor):
         yield from capa.features.extractors.dnfile.file.extract_features(self.pe)
 
     def get_functions(self) -> Iterator[FunctionHandle]:
-        for token, f in get_dotnet_managed_method_bodies(self.pe):
-            yield FunctionHandle(address=DNTokenAddress(Token(token)), inner=f, ctx={"pe": self.pe})
+        # create a method lookup table
+        methods: Dict[Address, FunctionHandle] = {}
+        for token, method in get_dotnet_managed_method_bodies(self.pe):
+            fh: FunctionHandle = FunctionHandle(
+                address=DNTokenAddress(token),
+                inner=method,
+                ctx={
+                    "pe": self.pe,
+                    "calls_from": set(),
+                    "calls_to": set(),
+                    "blocks": list(),
+                    "cache": self.token_cache,
+                },
+            )
 
-    def extract_function_features(self, f):
-        # TODO
-        yield from []
+            # method tokens should be unique
+            assert fh.address not in methods.keys()
+            methods[fh.address] = fh
 
-    def get_basic_blocks(self, f) -> Iterator[BBHandle]:
-        # each dotnet method is considered 1 basic block
-        yield BBHandle(
-            address=f.address,
-            inner=f.inner,
-        )
+        # calculate unique calls to/from each method
+        for fh in methods.values():
+            for insn in fh.inner.instructions:
+                if insn.opcode not in (
+                    OpCodes.Call,
+                    OpCodes.Callvirt,
+                    OpCodes.Jmp,
+                    OpCodes.Newobj,
+                ):
+                    continue
+
+                address: DNTokenAddress = DNTokenAddress(insn.operand.value)
+
+                # record call to destination method; note: we only consider MethodDef methods for destinations
+                dest: Optional[FunctionHandle] = methods.get(address, None)
+                if dest is not None:
+                    dest.ctx["calls_to"].add(fh.address)
+
+                # record call from source method; note: we record all unique calls from a MethodDef method, not just
+                # those calls to other MethodDef methods e.g. calls to imported MemberRef methods
+                fh.ctx["calls_from"].add(address)
+
+        # calculate basic blocks
+        for fh in methods.values():
+            # calculate basic block leaders where,
+            #   1. The first instruction of the intermediate code is a leader
+            #   2. Instructions that are targets of unconditional or conditional jump/goto statements are leaders
+            #   3. Instructions that immediately follow unconditional or conditional jump/goto statements are considered leaders
+            #   https://www.geeksforgeeks.org/basic-blocks-in-compiler-design/
+
+            leaders: Set[int] = set()
+            for idx, insn in enumerate(fh.inner.instructions):
+                if idx == 0:
+                    # add #1
+                    leaders.add(insn.offset)
+
+                if any((insn.is_br(), insn.is_cond_br(), insn.is_leave())):
+                    # add #2
+                    leaders.add(insn.operand)
+                    # add #3
+                    try:
+                        leaders.add(fh.inner.instructions[idx + 1].offset)
+                    except IndexError:
+                        # may encounter branch at end of method
+                        continue
+
+            # build basic blocks using leaders
+            bb_curr: Optional[DnBasicBlock] = None
+            for idx, insn in enumerate(fh.inner.instructions):
+                if insn.offset in leaders:
+                    # new leader, new basic block
+                    bb_curr = DnBasicBlock(instructions=[insn])
+                    fh.ctx["blocks"].append(bb_curr)
+                    continue
+
+                assert bb_curr is not None
+                bb_curr.instructions.append(insn)
+
+            # create mapping of first instruction to basic block
+            bb_map: Dict[int, DnBasicBlock] = {}
+            for bb in fh.ctx["blocks"]:
+                if len(bb.instructions) == 0:
+                    # TODO: consider error?
+                    continue
+                bb_map[bb.instructions[0].offset] = bb
+
+            # connect basic blocks
+            for idx, bb in enumerate(fh.ctx["blocks"]):
+                if len(bb.instructions) == 0:
+                    # TODO: consider error?
+                    continue
+
+                last = bb.instructions[-1]
+
+                # connect branches to other basic blocks
+                if any((last.is_br(), last.is_cond_br(), last.is_leave())):
+                    bb_branch: Optional[DnBasicBlock] = bb_map.get(last.operand, None)
+                    if bb_branch is not None:
+                        # TODO: consider None error?
+                        bb.succs.append(bb_branch)
+                        bb_branch.preds.append(bb)
+
+                if any((last.is_br(), last.is_leave())):
+                    # no fallthrough
+                    continue
+
+                # connect fallthrough
+                try:
+                    bb_next: DnBasicBlock = fh.ctx["blocks"][idx + 1]
+                    bb.succs.append(bb_next)
+                    bb_next.preds.append(bb)
+                except IndexError:
+                    continue
+
+        yield from methods.values()
+
+    def extract_function_features(self, fh) -> Iterator[Tuple[Feature, Address]]:
+        yield from capa.features.extractors.dnfile.function.extract_features(fh)
+
+    def get_basic_blocks(self, fh) -> Iterator[BBHandle]:
+        for bb in fh.ctx["blocks"]:
+            yield BBHandle(
+                address=DNTokenOffsetAddress(
+                    fh.address, bb.instructions[0].offset - (fh.inner.offset + fh.inner.header_size)
+                ),
+                inner=bb,
+            )
 
     def extract_basic_block_features(self, fh, bbh):
-        # we don't support basic block features
-        yield from []
+        yield from capa.features.extractors.dnfile.basicblock.extract_features(fh, bbh)
 
     def get_instructions(self, fh, bbh):
         for insn in bbh.inner.instructions:
             yield InsnHandle(
-                address=DNTokenOffsetAddress(bbh.address.token, insn.offset - (fh.inner.offset + fh.inner.header_size)),
+                address=DNTokenOffsetAddress(fh.address, insn.offset - (fh.inner.offset + fh.inner.header_size)),
                 inner=insn,
             )
 

capa/features/extractors/dnfile/file.py

@@ -48,7 +48,7 @@ def extract_file_class_features(pe: dnfile.dnPE) -> Iterator[Tuple[Class, Addres
 
 def extract_features(pe: dnfile.dnPE) -> Iterator[Tuple[Feature, Address]]:
     for file_handler in FILE_HANDLERS:
-        for (feature, address) in file_handler(pe):
+        for feature, address in file_handler(pe):
             yield feature, address
 
 

capa/features/extractors/dnfile/function.py

@@ -0,0 +1,62 @@
+# Copyright (C) 2020 Mandiant, Inc. All Rights Reserved.
+# Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at: [package root]/LICENSE.txt
+# Unless required by applicable law or agreed to in writing, software distributed under the License
+#  is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and limitations under the License.
+
+from __future__ import annotations
+
+import logging
+from typing import Tuple, Iterator
+
+from capa.features.common import Feature, Characteristic
+from capa.features.address import Address
+from capa.features.extractors import loops
+from capa.features.extractors.base_extractor import FunctionHandle
+
+logger = logging.getLogger(__name__)
+
+
+def extract_function_calls_to(fh: FunctionHandle) -> Iterator[Tuple[Characteristic, Address]]:
+    """extract callers to a function"""
+    for dest in fh.ctx["calls_to"]:
+        yield Characteristic("calls to"), dest
+
+
+def extract_function_calls_from(fh: FunctionHandle) -> Iterator[Tuple[Characteristic, Address]]:
+    """extract callers from a function"""
+    for src in fh.ctx["calls_from"]:
+        yield Characteristic("calls from"), src
+
+
+def extract_recursive_call(fh: FunctionHandle) -> Iterator[Tuple[Characteristic, Address]]:
+    """extract recursive function call"""
+    if fh.address in fh.ctx["calls_to"]:
+        yield Characteristic("recursive call"), fh.address
+
+
+def extract_function_loop(fh: FunctionHandle) -> Iterator[Tuple[Characteristic, Address]]:
+    """extract loop indicators from a function"""
+    edges = []
+    for bb in fh.ctx["blocks"]:
+        for succ in bb.succs:
+            edges.append((bb.instructions[0].offset, succ.instructions[0].offset))
+
+    if loops.has_loop(edges):
+        yield Characteristic("loop"), fh.address
+
+
+def extract_features(fh: FunctionHandle) -> Iterator[Tuple[Feature, Address]]:
+    for func_handler in FUNCTION_HANDLERS:
+        for feature, addr in func_handler(fh):
+            yield feature, addr
+
+
+FUNCTION_HANDLERS = (
+    extract_function_calls_to,
+    extract_function_calls_from,
+    extract_recursive_call,
+    extract_function_loop,
+)

capa/features/extractors/dnfile/helpers.py

@@ -9,7 +9,7 @@
 from __future__ import annotations
 
 import logging
-from typing import Any, Tuple, Iterator, Optional
+from typing import Dict, Tuple, Union, Iterator, Optional
 
 import dnfile
 from dncil.cil.body import CilMethodBody
@@ -17,10 +17,10 @@ from dncil.cil.error import MethodBodyFormatError
 from dncil.clr.token import Token, StringToken, InvalidToken
 from dncil.cil.body.reader import CilMethodBodyReaderBase
 
-logger = logging.getLogger(__name__)
+from capa.features.common import FeatureAccess
+from capa.features.extractors.dnfile.types import DnType, DnUnmanagedMethod
 
-# key indexes to dotnet metadata tables
-DOTNET_META_TABLES_BY_INDEX = {table.value: table.name for table in dnfile.enums.MetadataTables}
+logger = logging.getLogger(__name__)
 
 
 class DnfileMethodBodyReader(CilMethodBodyReaderBase):
@@ -41,90 +41,20 @@ class DnfileMethodBodyReader(CilMethodBodyReaderBase):
         return self.offset
 
 
-class DnClass(object):
-    def __init__(self, token: int, namespace: str, classname: str):
-        self.token: int = token
-        self.namespace: str = namespace
-        self.classname: str = classname
-
-    def __hash__(self):
-        return hash((self.token,))
-
-    def __eq__(self, other):
-        return self.token == other.token
-
-    def __str__(self):
-        return DnClass.format_name(self.namespace, self.classname)
-
-    def __repr__(self):
-        return str(self)
-
-    @staticmethod
-    def format_name(namespace: str, classname: str):
-        name: str = classname
-        if namespace:
-            # like System.IO.File::OpenRead
-            name = f"{namespace}.{name}"
-        return name
-
-
-class DnMethod(DnClass):
-    def __init__(self, token: int, namespace: str, classname: str, methodname: str):
-        super(DnMethod, self).__init__(token, namespace, classname)
-        self.methodname: str = methodname
-
-    def __str__(self):
-        return DnMethod.format_name(self.namespace, self.classname, self.methodname)
-
-    @staticmethod
-    def format_name(namespace: str, classname: str, methodname: str):  # type: ignore
-        # like File::OpenRead
-        name: str = f"{classname}::{methodname}"
-        if namespace:
-            # like System.IO.File::OpenRead
-            name = f"{namespace}.{name}"
-        return name
-
-
-class DnUnmanagedMethod:
-    def __init__(self, token: int, modulename: str, methodname: str):
-        self.token: int = token
-        self.modulename: str = modulename
-        self.methodname: str = methodname
-
-    def __hash__(self):
-        return hash((self.token,))
-
-    def __eq__(self, other):
-        return self.token == other.token
-
-    def __str__(self):
-        return DnUnmanagedMethod.format_name(self.modulename, self.methodname)
-
-    def __repr__(self):
-        return str(self)
-
-    @staticmethod
-    def format_name(modulename, methodname):
-        return f"{modulename}.{methodname}"
-
-
-def resolve_dotnet_token(pe: dnfile.dnPE, token: Token) -> Any:
+def resolve_dotnet_token(pe: dnfile.dnPE, token: Token) -> Union[dnfile.base.MDTableRow, InvalidToken, str]:
     """map generic token to string or table row"""
+    assert pe.net is not None
+    assert pe.net.mdtables is not None
+
     if isinstance(token, StringToken):
         user_string: Optional[str] = read_dotnet_user_string(pe, token)
         if user_string is None:
             return InvalidToken(token.value)
         return user_string
 
-    table_name: str = DOTNET_META_TABLES_BY_INDEX.get(token.table, "")
-    if not table_name:
-        # table_index is not valid
-        return InvalidToken(token.value)
-
-    table: Any = getattr(pe.net.mdtables, table_name, None)
+    table: Optional[dnfile.base.ClrMetaDataTable] = pe.net.mdtables.tables.get(token.table, None)
     if table is None:
-        # table index is valid but table is not present
+        # table index is not valid
         return InvalidToken(token.value)
 
     try:
@@ -139,16 +69,23 @@ def read_dotnet_method_body(pe: dnfile.dnPE, row: dnfile.mdtable.MethodDefRow) -
     try:
         return CilMethodBody(DnfileMethodBodyReader(pe, row))
     except MethodBodyFormatError as e:
-        logger.warn("failed to parse managed method body @ 0x%08x (%s)" % (row.Rva, e))
+        logger.debug("failed to parse managed method body @ 0x%08x (%s)", row.Rva, e)
         return None
 
 
 def read_dotnet_user_string(pe: dnfile.dnPE, token: StringToken) -> Optional[str]:
     """read user string from #US stream"""
+    assert pe.net is not None
+
+    if pe.net.user_strings is None:
+        # stream may not exist (seen in obfuscated .NET)
+        logger.debug("#US stream does not exist for stream index 0x%08x", token.rid)
+        return None
+
     try:
         user_string: Optional[dnfile.stream.UserString] = pe.net.user_strings.get_us(token.rid)
     except UnicodeDecodeError as e:
-        logger.warn("failed to decode #US stream index 0x%08x (%s)" % (token.rid, e))
+        logger.debug("failed to decode #US stream index 0x%08x (%s)", token.rid, e)
         return None
 
     if user_string is None:
@@ -157,7 +94,7 @@ def read_dotnet_user_string(pe: dnfile.dnPE, token: StringToken) -> Optional[str
     return user_string.value
 
 
-def get_dotnet_managed_imports(pe: dnfile.dnPE) -> Iterator[DnMethod]:
+def get_dotnet_managed_imports(pe: dnfile.dnPE) -> Iterator[DnType]:
     """get managed imports from MemberRef table
 
     see https://www.ntcore.com/files/dotnetformat.htm
@@ -171,15 +108,76 @@ def get_dotnet_managed_imports(pe: dnfile.dnPE) -> Iterator[DnMethod]:
             TypeName (index into String heap)
             TypeNamespace (index into String heap)
     """
-    for (rid, row) in enumerate(iter_dotnet_table(pe, "MemberRef")):
-        if not isinstance(row.Class.row, dnfile.mdtable.TypeRefRow):
+    for rid, member_ref in iter_dotnet_table(pe, dnfile.mdtable.MemberRef.number):
+        assert isinstance(member_ref, dnfile.mdtable.MemberRefRow)
+
+        if not isinstance(member_ref.Class.row, dnfile.mdtable.TypeRefRow):
+            # only process class imports from TypeRef table
             continue
 
-        token: int = calculate_dotnet_token_value(pe.net.mdtables.MemberRef.number, rid + 1)
-        yield DnMethod(token, row.Class.row.TypeNamespace, row.Class.row.TypeName, row.Name)
+        token: int = calculate_dotnet_token_value(dnfile.mdtable.MemberRef.number, rid)
+        access: Optional[str]
+
+        # assume .NET imports starting with get_/set_ are used to access a property
+        if member_ref.Name.startswith("get_"):
+            access = FeatureAccess.READ
+        elif member_ref.Name.startswith("set_"):
+            access = FeatureAccess.WRITE
+        else:
+            access = None
+
+        member_ref_name: str = member_ref.Name
+        if member_ref_name.startswith(("get_", "set_")):
+            # remove get_/set_ from MemberRef name
+            member_ref_name = member_ref_name[4:]
+
+        yield DnType(
+            token,
+            member_ref.Class.row.TypeName,
+            namespace=member_ref.Class.row.TypeNamespace,
+            member=member_ref_name,
+            access=access,
+        )
 
 
-def get_dotnet_managed_methods(pe: dnfile.dnPE) -> Iterator[DnMethod]:
+def get_dotnet_methoddef_property_accessors(pe: dnfile.dnPE) -> Iterator[Tuple[int, str]]:
+    """get MethodDef methods used to access properties
+
+    see https://www.ntcore.com/files/dotnetformat.htm
+
+    24 - MethodSemantics Table
+        Links Events and Properties to specific methods. For example one Event can be associated to more methods. A property uses this table to associate get/set methods.
+            Semantics (a 2-byte bitmask of type MethodSemanticsAttributes)
+            Method (index into the MethodDef table)
+            Association (index into the Event or Property table; more precisely, a HasSemantics coded index)
+    """
+    for rid, method_semantics in iter_dotnet_table(pe, dnfile.mdtable.MethodSemantics.number):
+        assert isinstance(method_semantics, dnfile.mdtable.MethodSemanticsRow)
+
+        if method_semantics.Association.row is None:
+            logger.debug("MethodSemantics[0x%X] Association row is None", rid)
+            continue
+
+        if isinstance(method_semantics.Association.row, dnfile.mdtable.EventRow):
+            # ignore events
+            logger.debug("MethodSemantics[0x%X] ignoring Event", rid)
+            continue
+
+        if method_semantics.Method.table is None:
+            logger.debug("MethodSemantics[0x%X] Method table is None", rid)
+            continue
+
+        token: int = calculate_dotnet_token_value(
+            method_semantics.Method.table.number, method_semantics.Method.row_index
+        )
+
+        if method_semantics.Semantics.msSetter:
+            yield token, FeatureAccess.WRITE
+        elif method_semantics.Semantics.msGetter:
+            yield token, FeatureAccess.READ
+
+
+def get_dotnet_managed_methods(pe: dnfile.dnPE) -> Iterator[DnType]:
     """get managed method names from TypeDef table
 
     see https://www.ntcore.com/files/dotnetformat.htm
@@ -188,29 +186,74 @@ def get_dotnet_managed_methods(pe: dnfile.dnPE) -> Iterator[DnMethod]:
         Each row represents a class in the current assembly.
             TypeName (index into String heap)
             TypeNamespace (index into String heap)
-            MethodList (index into MethodDef table; it marks the first of a continguous run of Methods owned by this Type)
+            MethodList (index into MethodDef table; it marks the first of a contiguous run of Methods owned by this Type)
     """
-    for row in iter_dotnet_table(pe, "TypeDef"):
-        for index in row.MethodList:
-            token = calculate_dotnet_token_value(index.table.number, index.row_index)
-            yield DnMethod(token, row.TypeNamespace, row.TypeName, index.row.Name)
+    accessor_map: Dict[int, str] = {}
+    for methoddef, methoddef_access in get_dotnet_methoddef_property_accessors(pe):
+        accessor_map[methoddef] = methoddef_access
+
+    for rid, typedef in iter_dotnet_table(pe, dnfile.mdtable.TypeDef.number):
+        assert isinstance(typedef, dnfile.mdtable.TypeDefRow)
+
+        for idx, method in enumerate(typedef.MethodList):
+            if method.table is None:
+                logger.debug("TypeDef[0x%X] MethodList[0x%X] table is None", rid, idx)
+                continue
+            if method.row is None:
+                logger.debug("TypeDef[0x%X] MethodList[0x%X] row is None", rid, idx)
+                continue
+
+            token: int = calculate_dotnet_token_value(method.table.number, method.row_index)
+            access: Optional[str] = accessor_map.get(token, None)
+
+            method_name: str = method.row.Name
+            if method_name.startswith(("get_", "set_")):
+                # remove get_/set_
+                method_name = method_name[4:]
+
+            yield DnType(token, typedef.TypeName, namespace=typedef.TypeNamespace, member=method_name, access=access)
+
+
+def get_dotnet_fields(pe: dnfile.dnPE) -> Iterator[DnType]:
+    """get fields from TypeDef table
+
+    see https://www.ntcore.com/files/dotnetformat.htm
+
+    02 - TypeDef Table
+        Each row represents a class in the current assembly.
+            TypeName (index into String heap)
+            TypeNamespace (index into String heap)
+            FieldList (index into Field table; it marks the first of a contiguous run of Fields owned by this Type)
+    """
+    for rid, typedef in iter_dotnet_table(pe, dnfile.mdtable.TypeDef.number):
+        assert isinstance(typedef, dnfile.mdtable.TypeDefRow)
+
+        for idx, field in enumerate(typedef.FieldList):
+            if field.table is None:
+                logger.debug("TypeDef[0x%X] FieldList[0x%X] table is None", rid, idx)
+                continue
+            if field.row is None:
+                logger.debug("TypeDef[0x%X] FieldList[0x%X] row is None", rid, idx)
+                continue
+            token: int = calculate_dotnet_token_value(field.table.number, field.row_index)
+            yield DnType(token, typedef.TypeName, namespace=typedef.TypeNamespace, member=field.row.Name)
 
 
 def get_dotnet_managed_method_bodies(pe: dnfile.dnPE) -> Iterator[Tuple[int, CilMethodBody]]:
     """get managed methods from MethodDef table"""
-    if not hasattr(pe.net.mdtables, "MethodDef"):
-        return
+    for rid, method_def in iter_dotnet_table(pe, dnfile.mdtable.MethodDef.number):
+        assert isinstance(method_def, dnfile.mdtable.MethodDefRow)
 
-    for (rid, row) in enumerate(pe.net.mdtables.MethodDef):
-        if not row.ImplFlags.miIL or any((row.Flags.mdAbstract, row.Flags.mdPinvokeImpl)):
+        if not method_def.ImplFlags.miIL or any((method_def.Flags.mdAbstract, method_def.Flags.mdPinvokeImpl)):
             # skip methods that do not have a method body
             continue
 
-        body: Optional[CilMethodBody] = read_dotnet_method_body(pe, row)
+        body: Optional[CilMethodBody] = read_dotnet_method_body(pe, method_def)
         if body is None:
+            logger.debug("MethodDef[0x%X] method body is None", rid)
             continue
 
-        token: int = calculate_dotnet_token_value(dnfile.enums.MetadataTables.MethodDef.value, rid + 1)
+        token: int = calculate_dotnet_token_value(dnfile.mdtable.MethodDef.number, rid)
         yield token, body
 
 
@@ -225,37 +268,68 @@ def get_dotnet_unmanaged_imports(pe: dnfile.dnPE) -> Iterator[DnUnmanagedMethod]
             ImportName (index into the String heap)
             ImportScope (index into the ModuleRef table)
     """
-    for row in iter_dotnet_table(pe, "ImplMap"):
-        modulename: str = row.ImportScope.row.Name
-        methodname: str = row.ImportName
+    for rid, impl_map in iter_dotnet_table(pe, dnfile.mdtable.ImplMap.number):
+        assert isinstance(impl_map, dnfile.mdtable.ImplMapRow)
+
+        module: str
+        if impl_map.ImportScope.row is None:
+            logger.debug("ImplMap[0x%X] ImportScope row is None", rid)
+            module = ""
+        else:
+            module = impl_map.ImportScope.row.Name
+        method: str = impl_map.ImportName
+
+        member_forward_table: int
+        if impl_map.MemberForwarded.table is None:
+            logger.debug("ImplMap[0x%X] MemberForwarded table is None", rid)
+            continue
+        else:
+            member_forward_table = impl_map.MemberForwarded.table.number
+        member_forward_row: int = impl_map.MemberForwarded.row_index
 
         # ECMA says "Each row of the ImplMap table associates a row in the MethodDef table (MemberForwarded) with the
         # name of a routine (ImportName) in some unmanaged DLL (ImportScope)"; so we calculate and map the MemberForwarded
         # MethodDef table token to help us later record native import method calls made from CIL
-        token: int = calculate_dotnet_token_value(row.MemberForwarded.table.number, row.MemberForwarded.row_index)
+        token: int = calculate_dotnet_token_value(member_forward_table, member_forward_row)
 
         # like Kernel32.dll
-        if modulename and "." in modulename:
-            modulename = modulename.split(".")[0]
+        if module and "." in module:
+            module = module.split(".")[0]
 
         # like kernel32.CreateFileA
-        yield DnUnmanagedMethod(token, modulename, methodname)
+        yield DnUnmanagedMethod(token, module, method)
+
+
+def get_dotnet_types(pe: dnfile.dnPE) -> Iterator[DnType]:
+    """get .NET types from TypeDef and TypeRef tables"""
+    for rid, typedef in iter_dotnet_table(pe, dnfile.mdtable.TypeDef.number):
+        assert isinstance(typedef, dnfile.mdtable.TypeDefRow)
+
+        typedef_token: int = calculate_dotnet_token_value(dnfile.mdtable.TypeDef.number, rid)
+        yield DnType(typedef_token, typedef.TypeName, namespace=typedef.TypeNamespace)
+
+    for rid, typeref in iter_dotnet_table(pe, dnfile.mdtable.TypeRef.number):
+        assert isinstance(typeref, dnfile.mdtable.TypeRefRow)
+
+        typeref_token: int = calculate_dotnet_token_value(dnfile.mdtable.TypeRef.number, rid)
+        yield DnType(typeref_token, typeref.TypeName, namespace=typeref.TypeNamespace)
 
 
 def calculate_dotnet_token_value(table: int, rid: int) -> int:
     return ((table & 0xFF) << Token.TABLE_SHIFT) | (rid & Token.RID_MASK)
 
 
-def is_dotnet_table_valid(pe: dnfile.dnPE, table_name: str) -> bool:
-    return bool(getattr(pe.net.mdtables, table_name, None))
-
-
 def is_dotnet_mixed_mode(pe: dnfile.dnPE) -> bool:
+    assert pe.net is not None
+    assert pe.net.Flags is not None
+
     return not bool(pe.net.Flags.CLR_ILONLY)
 
 
-def iter_dotnet_table(pe: dnfile.dnPE, name: str) -> Iterator[Any]:
-    if not is_dotnet_table_valid(pe, name):
-        return
-    for row in getattr(pe.net.mdtables, name):
-        yield row
+def iter_dotnet_table(pe: dnfile.dnPE, table_index: int) -> Iterator[Tuple[int, dnfile.base.MDTableRow]]:
+    assert pe.net is not None
+    assert pe.net.mdtables is not None
+
+    for rid, row in enumerate(pe.net.mdtables.tables.get(table_index, [])):
+        # .NET tables are 1-indexed
+        yield rid + 1, row

capa/features/extractors/dnfile/insn.py

@@ -8,175 +8,220 @@
 
 from __future__ import annotations
 
-from typing import Any, Dict, Tuple, Union, Iterator, Optional
+import logging
+from typing import TYPE_CHECKING, Any, Dict, Tuple, Union, Iterator, Optional
+
+if TYPE_CHECKING:
+    from capa.features.extractors.dnfile.extractor import DnFileFeatureExtractorCache
 
 import dnfile
-from dncil.cil.body import CilMethodBody
 from dncil.clr.token import Token, StringToken, InvalidToken
 from dncil.cil.opcode import OpCodes
-from dncil.cil.instruction import Instruction
 
 import capa.features.extractors.helpers
-from capa.features.insn import API, Number
-from capa.features.common import Class, String, Feature, Namespace, Characteristic
+from capa.features.insn import API, Number, Property
+from capa.features.common import Class, String, Feature, Namespace, FeatureAccess, Characteristic
 from capa.features.address import Address
+from capa.features.extractors.dnfile.types import DnType, DnUnmanagedMethod
 from capa.features.extractors.base_extractor import BBHandle, InsnHandle, FunctionHandle
 from capa.features.extractors.dnfile.helpers import (
-    DnClass,
-    DnMethod,
-    DnUnmanagedMethod,
     resolve_dotnet_token,
     read_dotnet_user_string,
-    get_dotnet_managed_imports,
-    get_dotnet_managed_methods,
-    get_dotnet_unmanaged_imports,
+    calculate_dotnet_token_value,
 )
 
-
-def get_managed_imports(ctx: Dict) -> Dict:
-    if "managed_imports_cache" not in ctx:
-        ctx["managed_imports_cache"] = {}
-        for method in get_dotnet_managed_imports(ctx["pe"]):
-            ctx["managed_imports_cache"][method.token] = method
-    return ctx["managed_imports_cache"]
+logger = logging.getLogger(__name__)
 
 
-def get_unmanaged_imports(ctx: Dict) -> Dict:
-    if "unmanaged_imports_cache" not in ctx:
-        ctx["unmanaged_imports_cache"] = {}
-        for imp in get_dotnet_unmanaged_imports(ctx["pe"]):
-            ctx["unmanaged_imports_cache"][imp.token] = imp
-    return ctx["unmanaged_imports_cache"]
+def get_callee(
+    pe: dnfile.dnPE, cache: DnFileFeatureExtractorCache, token: Token
+) -> Optional[Union[DnType, DnUnmanagedMethod]]:
+    """map .NET token to un/managed (generic) method"""
+    token_: int
+    if token.table == dnfile.mdtable.MethodSpec.number:
+        # map MethodSpec to MethodDef or MemberRef
+        row: Union[dnfile.base.MDTableRow, InvalidToken, str] = resolve_dotnet_token(pe, token)
+        assert isinstance(row, dnfile.mdtable.MethodSpecRow)
 
+        if row.Method.table is None:
+            logger.debug("MethodSpec[0x%X] Method table is None", token.rid)
+            return None
 
-def get_methods(ctx: Dict) -> Dict:
-    if "methods_cache" not in ctx:
-        ctx["methods_cache"] = {}
-        for method in get_dotnet_managed_methods(ctx["pe"]):
-            ctx["methods_cache"][method.token] = method
-    return ctx["methods_cache"]
+        token_ = calculate_dotnet_token_value(row.Method.table.number, row.Method.row_index)
+    else:
+        token_ = token.value
 
-
-def get_callee(ctx: Dict, token: int) -> Union[DnMethod, DnUnmanagedMethod, None]:
-    """map dotnet token to un/managed method"""
-    callee: Union[DnMethod, DnUnmanagedMethod, None] = get_managed_imports(ctx).get(token, None)
-    if not callee:
+    callee: Optional[Union[DnType, DnUnmanagedMethod]] = cache.get_import(token_)
+    if callee is None:
         # we must check unmanaged imports before managed methods because we map forwarded managed methods
         # to their unmanaged imports; we prefer a forwarded managed method be mapped to its unmanaged import for analysis
-        callee = get_unmanaged_imports(ctx).get(token, None)
-        if not callee:
-            callee = get_methods(ctx).get(token, None)
+        callee = cache.get_native_import(token_)
+        if callee is None:
+            callee = cache.get_method(token_)
     return callee
 
 
 def extract_insn_api_features(fh: FunctionHandle, bh, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
     """parse instruction API features"""
-    insn: Instruction = ih.inner
-
-    if insn.opcode not in (OpCodes.Call, OpCodes.Callvirt, OpCodes.Jmp, OpCodes.Calli):
+    if ih.inner.opcode not in (
+        OpCodes.Call,
+        OpCodes.Callvirt,
+        OpCodes.Jmp,
+        OpCodes.Newobj,
+    ):
         return
 
-    callee: Union[DnMethod, DnUnmanagedMethod, None] = get_callee(fh.ctx, insn.operand.value)
-    if callee is None:
-        return
-
-    if isinstance(callee, DnUnmanagedMethod):
+    callee: Optional[Union[DnType, DnUnmanagedMethod]] = get_callee(fh.ctx["pe"], fh.ctx["cache"], ih.inner.operand)
+    if isinstance(callee, DnType):
+        # ignore methods used to access properties
+        if callee.access is None:
+            # like System.IO.File::Delete
+            yield API(str(callee)), ih.address
+    elif isinstance(callee, DnUnmanagedMethod):
         # like kernel32.CreateFileA
-        for name in capa.features.extractors.helpers.generate_symbols(callee.modulename, callee.methodname):
+        for name in capa.features.extractors.helpers.generate_symbols(callee.module, callee.method):
             yield API(name), ih.address
-    else:
-        # like System.IO.File::Delete
-        yield API(str(callee)), ih.address
 
 
-def extract_insn_class_features(fh: FunctionHandle, bh, ih: InsnHandle) -> Iterator[Tuple[Class, Address]]:
-    """parse instruction class features"""
-    if ih.inner.opcode not in (OpCodes.Call, OpCodes.Callvirt, OpCodes.Jmp, OpCodes.Calli):
-        return
+def extract_insn_property_features(fh: FunctionHandle, bh, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
+    """parse instruction property features"""
+    name: Optional[str] = None
+    access: Optional[str] = None
 
-    row: Any = resolve_dotnet_token(fh.ctx["pe"], Token(ih.inner.operand.value))
+    if ih.inner.opcode in (OpCodes.Call, OpCodes.Callvirt, OpCodes.Jmp):
+        # property access via MethodDef or MemberRef
+        callee: Optional[Union[DnType, DnUnmanagedMethod]] = get_callee(fh.ctx["pe"], fh.ctx["cache"], ih.inner.operand)
+        if isinstance(callee, DnType):
+            if callee.access is not None:
+                name = str(callee)
+                access = callee.access
 
-    if not isinstance(row, dnfile.mdtable.MemberRefRow):
-        return
-    if not isinstance(row.Class.row, (dnfile.mdtable.TypeRefRow, dnfile.mdtable.TypeDefRow)):
-        return
+    elif ih.inner.opcode in (OpCodes.Ldfld, OpCodes.Ldflda, OpCodes.Ldsfld, OpCodes.Ldsflda):
+        # property read via Field
+        read_field: Optional[Union[DnType, DnUnmanagedMethod]] = fh.ctx["cache"].get_field(ih.inner.operand.value)
+        if read_field is not None:
+            name = str(read_field)
+            access = FeatureAccess.READ
 
-    yield Class(DnClass.format_name(row.Class.row.TypeNamespace, row.Class.row.TypeName)), ih.address
+    elif ih.inner.opcode in (OpCodes.Stfld, OpCodes.Stsfld):
+        # property write via Field
+        write_field: Optional[Union[DnType, DnUnmanagedMethod]] = fh.ctx["cache"].get_field(ih.inner.operand.value)
+        if write_field is not None:
+            name = str(write_field)
+            access = FeatureAccess.WRITE
+
+    if name is not None:
+        if access is not None:
+            yield Property(name, access=access), ih.address
+        yield Property(name), ih.address
 
 
-def extract_insn_namespace_features(fh: FunctionHandle, bh, ih: InsnHandle) -> Iterator[Tuple[Namespace, Address]]:
-    """parse instruction namespace features"""
-    if ih.inner.opcode not in (OpCodes.Call, OpCodes.Callvirt, OpCodes.Jmp, OpCodes.Calli):
-        return
+def extract_insn_namespace_class_features(
+    fh: FunctionHandle, bh, ih: InsnHandle
+) -> Iterator[Tuple[Union[Namespace, Class], Address]]:
+    """parse instruction namespace and class features"""
+    type_: Optional[Union[DnType, DnUnmanagedMethod]] = None
 
-    row: Any = resolve_dotnet_token(fh.ctx["pe"], Token(ih.inner.operand.value))
+    if ih.inner.opcode in (
+        OpCodes.Call,
+        OpCodes.Callvirt,
+        OpCodes.Jmp,
+        OpCodes.Ldvirtftn,
+        OpCodes.Ldftn,
+        OpCodes.Newobj,
+    ):
+        # method call - includes managed methods (MethodDef, TypeRef) and properties (MethodSemantics, TypeRef)
+        type_ = get_callee(fh.ctx["pe"], fh.ctx["cache"], ih.inner.operand)
 
-    if not isinstance(row, dnfile.mdtable.MemberRefRow):
-        return
-    if not isinstance(row.Class.row, (dnfile.mdtable.TypeRefRow, dnfile.mdtable.TypeDefRow)):
-        return
-    if not row.Class.row.TypeNamespace:
-        return
+    elif ih.inner.opcode in (
+        OpCodes.Ldfld,
+        OpCodes.Ldflda,
+        OpCodes.Ldsfld,
+        OpCodes.Ldsflda,
+        OpCodes.Stfld,
+        OpCodes.Stsfld,
+    ):
+        # field access
+        type_ = fh.ctx["cache"].get_field(ih.inner.operand.value)
 
-    yield Namespace(row.Class.row.TypeNamespace), ih.address
+    # ECMA 335 VI.C.4.10
+    elif ih.inner.opcode in (
+        OpCodes.Initobj,
+        OpCodes.Box,
+        OpCodes.Castclass,
+        OpCodes.Cpobj,
+        OpCodes.Isinst,
+        OpCodes.Ldelem,
+        OpCodes.Ldelema,
+        OpCodes.Ldobj,
+        OpCodes.Mkrefany,
+        OpCodes.Newarr,
+        OpCodes.Refanyval,
+        OpCodes.Sizeof,
+        OpCodes.Stobj,
+        OpCodes.Unbox,
+        OpCodes.Constrained,
+        OpCodes.Stelem,
+        OpCodes.Unbox_Any,
+    ):
+        # type access
+        type_ = fh.ctx["cache"].get_type(ih.inner.operand.value)
+
+    if isinstance(type_, DnType):
+        yield Class(DnType.format_name(type_.class_, namespace=type_.namespace)), ih.address
+        if type_.namespace:
+            yield Namespace(type_.namespace), ih.address
 
 
 def extract_insn_number_features(fh, bh, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
     """parse instruction number features"""
-    insn: Instruction = ih.inner
-
-    if insn.is_ldc():
-        yield Number(insn.get_ldc()), ih.address
+    if ih.inner.is_ldc():
+        yield Number(ih.inner.get_ldc()), ih.address
 
 
 def extract_insn_string_features(fh: FunctionHandle, bh, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
     """parse instruction string features"""
-    f: CilMethodBody = fh.inner
-    insn: Instruction = ih.inner
-
-    if not insn.is_ldstr():
+    if not ih.inner.is_ldstr():
         return
 
-    if not isinstance(insn.operand, StringToken):
+    if not isinstance(ih.inner.operand, StringToken):
         return
 
-    user_string: Optional[str] = read_dotnet_user_string(fh.ctx["pe"], insn.operand)
+    user_string: Optional[str] = read_dotnet_user_string(fh.ctx["pe"], ih.inner.operand)
     if user_string is None:
         return
 
-    yield String(user_string), ih.address
+    if len(user_string) >= 4:
+        yield String(user_string), ih.address
 
 
 def extract_unmanaged_call_characteristic_features(
     fh: FunctionHandle, bb: BBHandle, ih: InsnHandle
 ) -> Iterator[Tuple[Characteristic, Address]]:
-    insn: Instruction = ih.inner
-    if insn.opcode not in (OpCodes.Call, OpCodes.Callvirt, OpCodes.Jmp, OpCodes.Calli):
+    if ih.inner.opcode not in (OpCodes.Call, OpCodes.Callvirt, OpCodes.Jmp):
         return
 
-    token: Any = resolve_dotnet_token(fh.ctx["pe"], insn.operand)
-    if isinstance(token, InvalidToken):
-        return
-    if not isinstance(token, dnfile.mdtable.MethodDefRow):
+    row: Union[str, InvalidToken, dnfile.base.MDTableRow] = resolve_dotnet_token(fh.ctx["pe"], ih.inner.operand)
+    if not isinstance(row, dnfile.mdtable.MethodDefRow):
         return
 
-    if any((token.Flags.mdPinvokeImpl, token.ImplFlags.miUnmanaged, token.ImplFlags.miNative)):
+    if any((row.Flags.mdPinvokeImpl, row.ImplFlags.miUnmanaged, row.ImplFlags.miNative)):
         yield Characteristic("unmanaged call"), ih.address
 
 
 def extract_features(fh: FunctionHandle, bbh: BBHandle, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
     """extract instruction features"""
     for inst_handler in INSTRUCTION_HANDLERS:
-        for (feature, addr) in inst_handler(fh, bbh, ih):
+        for feature, addr in inst_handler(fh, bbh, ih):
             assert isinstance(addr, Address)
             yield feature, addr
 
 
 INSTRUCTION_HANDLERS = (
     extract_insn_api_features,
+    extract_insn_property_features,
     extract_insn_number_features,
     extract_insn_string_features,
-    extract_insn_namespace_features,
-    extract_insn_class_features,
+    extract_insn_namespace_class_features,
     extract_unmanaged_call_characteristic_features,
 )

capa/features/extractors/dnfile/types.py

@@ -0,0 +1,84 @@
+# Copyright (C) 2020 Mandiant, Inc. All Rights Reserved.
+# Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at: [package root]/LICENSE.txt
+# Unless required by applicable law or agreed to in writing, software distributed under the License
+#  is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and limitations under the License.
+
+from typing import TYPE_CHECKING, Dict, List, Optional
+
+if TYPE_CHECKING:
+    from dncil.cil.instruction import Instruction
+
+
+class DnType(object):
+    def __init__(self, token: int, class_: str, namespace: str = "", member: str = "", access: Optional[str] = None):
+        self.token: int = token
+        self.access: Optional[str] = access
+        self.namespace: str = namespace
+        self.class_: str = class_
+
+        if member == ".ctor":
+            member = "ctor"
+        if member == ".cctor":
+            member = "cctor"
+
+        self.member: str = member
+
+    def __hash__(self):
+        return hash((self.token, self.access, self.namespace, self.class_, self.member))
+
+    def __eq__(self, other):
+        return (
+            self.token == other.token
+            and self.access == other.access
+            and self.namespace == other.namespace
+            and self.class_ == other.class_
+            and self.member == other.member
+        )
+
+    def __str__(self):
+        return DnType.format_name(self.class_, namespace=self.namespace, member=self.member)
+
+    def __repr__(self):
+        return str(self)
+
+    @staticmethod
+    def format_name(class_: str, namespace: str = "", member: str = ""):
+        # like File::OpenRead
+        name: str = f"{class_}::{member}" if member else class_
+        if namespace:
+            # like System.IO.File::OpenRead
+            name = f"{namespace}.{name}"
+        return name
+
+
+class DnUnmanagedMethod:
+    def __init__(self, token: int, module: str, method: str):
+        self.token: int = token
+        self.module: str = module
+        self.method: str = method
+
+    def __hash__(self):
+        return hash((self.token, self.module, self.method))
+
+    def __eq__(self, other):
+        return self.token == other.token and self.module == other.module and self.method == other.method
+
+    def __str__(self):
+        return DnUnmanagedMethod.format_name(self.module, self.method)
+
+    def __repr__(self):
+        return str(self)
+
+    @staticmethod
+    def format_name(module, method):
+        return f"{module}.{method}"
+
+
+class DnBasicBlock:
+    def __init__(self, preds=None, succs=None, instructions=None):
+        self.succs: List[DnBasicBlock] = succs or []
+        self.preds: List[DnBasicBlock] = preds or []
+        self.instructions: List[Instruction] = instructions or []

capa/features/extractors/dnfile_.py

@@ -4,7 +4,18 @@ from typing import Tuple, Iterator
 import dnfile
 import pefile
 
-from capa.features.common import OS, OS_ANY, ARCH_ANY, ARCH_I386, ARCH_AMD64, FORMAT_DOTNET, Arch, Format, Feature
+from capa.features.common import (
+    OS,
+    OS_ANY,
+    ARCH_ANY,
+    ARCH_I386,
+    FORMAT_PE,
+    ARCH_AMD64,
+    FORMAT_DOTNET,
+    Arch,
+    Format,
+    Feature,
+)
 from capa.features.address import NO_ADDRESS, Address, AbsoluteVirtualAddress
 from capa.features.extractors.base_extractor import FeatureExtractor
 
@@ -12,6 +23,7 @@ logger = logging.getLogger(__name__)
 
 
 def extract_file_format(**kwargs) -> Iterator[Tuple[Feature, Address]]:
+    yield Format(FORMAT_PE), NO_ADDRESS
     yield Format(FORMAT_DOTNET), NO_ADDRESS
 
 
@@ -19,9 +31,12 @@ def extract_file_os(**kwargs) -> Iterator[Tuple[Feature, Address]]:
     yield OS(OS_ANY), NO_ADDRESS
 
 
-def extract_file_arch(pe, **kwargs) -> Iterator[Tuple[Feature, Address]]:
+def extract_file_arch(pe: dnfile.dnPE, **kwargs) -> Iterator[Tuple[Feature, Address]]:
     # to distinguish in more detail, see https://stackoverflow.com/a/23614024/10548020
     # .NET 4.5 added option: any CPU, 32-bit preferred
+    assert pe.net is not None
+    assert pe.net.Flags is not None
+
     if pe.net.Flags.CLR_32BITREQUIRED and pe.PE_TYPE == pefile.OPTIONAL_HEADER_MAGIC_PE:
         yield Arch(ARCH_I386), NO_ADDRESS
     elif not pe.net.Flags.CLR_32BITREQUIRED and pe.PE_TYPE == pefile.OPTIONAL_HEADER_MAGIC_PE_PLUS:
@@ -60,7 +75,7 @@ GLOBAL_HANDLERS = (
 
 class DnfileFeatureExtractor(FeatureExtractor):
     def __init__(self, path: str):
-        super(DnfileFeatureExtractor, self).__init__()
+        super().__init__()
         self.path: str = path
         self.pe: dnfile.dnPE = dnfile.dnPE(path)
 
@@ -71,6 +86,9 @@ class DnfileFeatureExtractor(FeatureExtractor):
         # self.pe.net.Flags.CLT_NATIVE_ENTRYPOINT
         #  True: native EP: Token
         #  False: managed EP: RVA
+        assert self.pe.net is not None
+        assert self.pe.net.struct is not None
+
         return self.pe.net.struct.EntryPointTokenOrRva
 
     def extract_global_features(self):
@@ -83,13 +101,29 @@ class DnfileFeatureExtractor(FeatureExtractor):
         return bool(self.pe.net)
 
     def is_mixed_mode(self) -> bool:
+        assert self.pe is not None
+        assert self.pe.net is not None
+        assert self.pe.net.Flags is not None
+
         return not bool(self.pe.net.Flags.CLR_ILONLY)
 
     def get_runtime_version(self) -> Tuple[int, int]:
+        assert self.pe is not None
+        assert self.pe.net is not None
+        assert self.pe.net.struct is not None
+
         return self.pe.net.struct.MajorRuntimeVersion, self.pe.net.struct.MinorRuntimeVersion
 
     def get_meta_version_string(self) -> str:
-        return self.pe.net.metadata.struct.Version.rstrip(b"\x00").decode("utf-8")
+        assert self.pe.net is not None
+        assert self.pe.net.metadata is not None
+        assert self.pe.net.metadata.struct is not None
+        assert self.pe.net.metadata.struct.Version is not None
+
+        vbuf = self.pe.net.metadata.struct.Version
+        assert isinstance(vbuf, bytes)
+
+        return vbuf.rstrip(b"\x00").decode("utf-8")
 
     def get_functions(self):
         raise NotImplementedError("DnfileFeatureExtractor can only be used to extract file features")

capa/features/extractors/dotnetfile.py

@@ -1,10 +1,8 @@
 import logging
-import itertools
-from typing import Tuple, Iterator
+from typing import Tuple, Iterator, cast
 
 import dnfile
 import pefile
-from dncil.clr.token import Token
 
 import capa.features.extractors.helpers
 from capa.features.file import Import, FunctionName
@@ -13,6 +11,7 @@ from capa.features.common import (
     OS_ANY,
     ARCH_ANY,
     ARCH_I386,
+    FORMAT_PE,
     ARCH_AMD64,
     FORMAT_DOTNET,
     Arch,
@@ -23,11 +22,10 @@ from capa.features.common import (
     Namespace,
     Characteristic,
 )
-from capa.features.address import NO_ADDRESS, Address, DNTokenAddress, DNTokenOffsetAddress, AbsoluteVirtualAddress
+from capa.features.address import NO_ADDRESS, Address, DNTokenAddress
 from capa.features.extractors.base_extractor import FeatureExtractor
 from capa.features.extractors.dnfile.helpers import (
-    DnClass,
-    DnMethod,
+    DnType,
     iter_dotnet_table,
     is_dotnet_mixed_mode,
     get_dotnet_managed_imports,
@@ -40,23 +38,24 @@ logger = logging.getLogger(__name__)
 
 
 def extract_file_format(**kwargs) -> Iterator[Tuple[Format, Address]]:
+    yield Format(FORMAT_PE), NO_ADDRESS
     yield Format(FORMAT_DOTNET), NO_ADDRESS
 
 
 def extract_file_import_names(pe: dnfile.dnPE, **kwargs) -> Iterator[Tuple[Import, Address]]:
     for method in get_dotnet_managed_imports(pe):
         # like System.IO.File::OpenRead
-        yield Import(str(method)), DNTokenAddress(Token(method.token))
+        yield Import(str(method)), DNTokenAddress(method.token)
 
     for imp in get_dotnet_unmanaged_imports(pe):
         # like kernel32.CreateFileA
-        for name in capa.features.extractors.helpers.generate_symbols(imp.modulename, imp.methodname):
-            yield Import(name), DNTokenAddress(Token(imp.token))
+        for name in capa.features.extractors.helpers.generate_symbols(imp.module, imp.method):
+            yield Import(name), DNTokenAddress(imp.token)
 
 
 def extract_file_function_names(pe: dnfile.dnPE, **kwargs) -> Iterator[Tuple[FunctionName, Address]]:
     for method in get_dotnet_managed_methods(pe):
-        yield FunctionName(str(method)), DNTokenAddress(Token(method.token))
+        yield FunctionName(str(method)), DNTokenAddress(method.token)
 
 
 def extract_file_namespace_features(pe: dnfile.dnPE, **kwargs) -> Iterator[Tuple[Namespace, Address]]:
@@ -65,11 +64,15 @@ def extract_file_namespace_features(pe: dnfile.dnPE, **kwargs) -> Iterator[Tuple
     # namespaces may be referenced multiple times, so we need to filter
     namespaces = set()
 
-    for row in iter_dotnet_table(pe, "TypeDef"):
-        namespaces.add(row.TypeNamespace)
+    for _, typedef in iter_dotnet_table(pe, dnfile.mdtable.TypeDef.number):
+        # emit internal .NET namespaces
+        assert isinstance(typedef, dnfile.mdtable.TypeDefRow)
+        namespaces.add(typedef.TypeNamespace)
 
-    for row in iter_dotnet_table(pe, "TypeRef"):
-        namespaces.add(row.TypeNamespace)
+    for _, typeref in iter_dotnet_table(pe, dnfile.mdtable.TypeRef.number):
+        # emit external .NET namespaces
+        assert isinstance(typeref, dnfile.mdtable.TypeRefRow)
+        namespaces.add(typeref.TypeNamespace)
 
     # namespaces may be empty, discard
     namespaces.discard("")
@@ -81,13 +84,19 @@ def extract_file_namespace_features(pe: dnfile.dnPE, **kwargs) -> Iterator[Tuple
 
 def extract_file_class_features(pe: dnfile.dnPE, **kwargs) -> Iterator[Tuple[Class, Address]]:
     """emit class features from TypeRef and TypeDef tables"""
-    for (rid, row) in enumerate(iter_dotnet_table(pe, "TypeDef")):
-        token = calculate_dotnet_token_value(pe.net.mdtables.TypeDef.number, rid + 1)
-        yield Class(DnClass.format_name(row.TypeNamespace, row.TypeName)), DNTokenAddress(Token(token))
+    for rid, typedef in iter_dotnet_table(pe, dnfile.mdtable.TypeDef.number):
+        # emit internal .NET classes
+        assert isinstance(typedef, dnfile.mdtable.TypeDefRow)
 
-    for (rid, row) in enumerate(iter_dotnet_table(pe, "TypeRef")):
-        token = calculate_dotnet_token_value(pe.net.mdtables.TypeRef.number, rid + 1)
-        yield Class(DnClass.format_name(row.TypeNamespace, row.TypeName)), DNTokenAddress(Token(token))
+        token = calculate_dotnet_token_value(dnfile.mdtable.TypeDef.number, rid)
+        yield Class(DnType.format_name(typedef.TypeName, namespace=typedef.TypeNamespace)), DNTokenAddress(token)
+
+    for rid, typeref in iter_dotnet_table(pe, dnfile.mdtable.TypeRef.number):
+        # emit external .NET classes
+        assert isinstance(typeref, dnfile.mdtable.TypeRefRow)
+
+        token = calculate_dotnet_token_value(dnfile.mdtable.TypeRef.number, rid)
+        yield Class(DnType.format_name(typeref.TypeName, namespace=typeref.TypeNamespace)), DNTokenAddress(token)
 
 
 def extract_file_os(**kwargs) -> Iterator[Tuple[OS, Address]]:
@@ -97,6 +106,9 @@ def extract_file_os(**kwargs) -> Iterator[Tuple[OS, Address]]:
 def extract_file_arch(pe: dnfile.dnPE, **kwargs) -> Iterator[Tuple[Arch, Address]]:
     # to distinguish in more detail, see https://stackoverflow.com/a/23614024/10548020
     # .NET 4.5 added option: any CPU, 32-bit preferred
+    assert pe.net is not None
+    assert pe.net.Flags is not None
+
     if pe.net.Flags.CLR_32BITREQUIRED and pe.PE_TYPE == pefile.OPTIONAL_HEADER_MAGIC_PE:
         yield Arch(ARCH_I386), NO_ADDRESS
     elif not pe.net.Flags.CLR_32BITREQUIRED and pe.PE_TYPE == pefile.OPTIONAL_HEADER_MAGIC_PE_PLUS:
@@ -147,7 +159,7 @@ GLOBAL_HANDLERS = (
 
 class DotnetFileFeatureExtractor(FeatureExtractor):
     def __init__(self, path: str):
-        super(DotnetFileFeatureExtractor, self).__init__()
+        super().__init__()
         self.path: str = path
         self.pe: dnfile.dnPE = dnfile.dnPE(path)
 
@@ -158,6 +170,9 @@ class DotnetFileFeatureExtractor(FeatureExtractor):
         # self.pe.net.Flags.CLT_NATIVE_ENTRYPOINT
         #  True: native EP: Token
         #  False: managed EP: RVA
+        assert self.pe.net is not None
+        assert self.pe.net.struct is not None
+
         return self.pe.net.struct.EntryPointTokenOrRva
 
     def extract_global_features(self):
@@ -173,10 +188,23 @@ class DotnetFileFeatureExtractor(FeatureExtractor):
         return is_dotnet_mixed_mode(self.pe)
 
     def get_runtime_version(self) -> Tuple[int, int]:
+        assert self.pe.net is not None
+        assert self.pe.net.struct is not None
+        assert self.pe.net.struct.MajorRuntimeVersion is not None
+        assert self.pe.net.struct.MinorRuntimeVersion is not None
+
         return self.pe.net.struct.MajorRuntimeVersion, self.pe.net.struct.MinorRuntimeVersion
 
     def get_meta_version_string(self) -> str:
-        return self.pe.net.metadata.struct.Version.rstrip(b"\x00").decode("utf-8")
+        assert self.pe.net is not None
+        assert self.pe.net.metadata is not None
+        assert self.pe.net.metadata.struct is not None
+        assert self.pe.net.metadata.struct.Version is not None
+
+        vbuf = self.pe.net.metadata.struct.Version
+        assert isinstance(vbuf, bytes)
+
+        return vbuf.rstrip(b"\x00").decode("utf-8")
 
     def get_functions(self):
         raise NotImplementedError("DotnetFileFeatureExtractor can only be used to extract file features")

capa/features/extractors/elf.py

@@ -7,8 +7,11 @@
 # See the License for the specific language governing permissions and limitations under the License.
 import struct
 import logging
+import itertools
+import collections
 from enum import Enum
-from typing import BinaryIO
+from typing import Set, Dict, List, Tuple, BinaryIO, Iterator, Optional
+from dataclasses import dataclass
 
 logger = logging.getLogger(__name__)
 
@@ -21,6 +24,12 @@ def align(v, alignment):
         return v + (alignment - remainder)
 
 
+def read_cstr(buf, offset):
+    s = buf[offset:]
+    s, _, _ = s.partition(b"\x00")
+    return s.decode("utf-8")
+
+
 class CorruptElfFile(ValueError):
     pass
 
@@ -60,52 +69,94 @@ GNU_ABI_TAG = {
 }
 
 
-def detect_elf_os(f) -> str:
-    """
-    f: type Union[BinaryIO, IDAIO]
-    """
-    f.seek(0x0)
-    file_header = f.read(0x40)
+@dataclass
+class Phdr:
+    type: int
+    offset: int
+    vaddr: int
+    paddr: int
+    filesz: int
+    buf: bytes
 
-    # we'll set this to the detected OS
-    # prefer the first heuristics,
-    # but rather than short circuiting,
-    # we'll still parse out the remainder, for debugging.
-    ret = None
 
-    if not file_header.startswith(b"\x7fELF"):
-        raise CorruptElfFile("missing magic header")
+@dataclass
+class Shdr:
+    name: int
+    type: int
+    flags: int
+    addr: int
+    offset: int
+    size: int
+    link: int
+    buf: bytes
 
-    ei_class, ei_data = struct.unpack_from("BB", file_header, 4)
-    logger.debug("ei_class: 0x%02x ei_data: 0x%02x", ei_class, ei_data)
-    if ei_class == 1:
-        bitness = 32
-    elif ei_class == 2:
-        bitness = 64
-    else:
-        raise CorruptElfFile("invalid ei_class: 0x%02x" % ei_class)
 
-    if ei_data == 1:
-        endian = "<"
-    elif ei_data == 2:
-        endian = ">"
-    else:
-        raise CorruptElfFile("not an ELF file: invalid ei_data: 0x%02x" % ei_data)
+class ELF:
+    def __init__(self, f: BinaryIO):
+        self.f = f
 
-    if bitness == 32:
-        (e_phoff, e_shoff) = struct.unpack_from(endian + "II", file_header, 0x1C)
-        e_phentsize, e_phnum = struct.unpack_from(endian + "HH", file_header, 0x2A)
-        e_shentsize, e_shnum = struct.unpack_from(endian + "HH", file_header, 0x2E)
-    elif bitness == 64:
-        (e_phoff, e_shoff) = struct.unpack_from(endian + "QQ", file_header, 0x20)
-        e_phentsize, e_phnum = struct.unpack_from(endian + "HH", file_header, 0x36)
-        e_shentsize, e_shnum = struct.unpack_from(endian + "HH", file_header, 0x3A)
-    else:
-        raise NotImplementedError()
+        # these will all be initialized in `_parse()`
+        self.bitness: int
+        self.endian: str
+        self.e_phentsize: int
+        self.e_phnum: int
+        self.e_shentsize: int
+        self.e_shnum: int
+        self.phbuf: bytes
+        self.shbuf: bytes
 
-    logger.debug("e_phoff: 0x%02x e_phentsize: 0x%02x e_phnum: %d", e_phoff, e_phentsize, e_phnum)
+        self._parse()
+
+    def _parse(self):
+        self.f.seek(0x0)
+        self.file_header = self.f.read(0x40)
+
+        if not self.file_header.startswith(b"\x7fELF"):
+            raise CorruptElfFile("missing magic header")
+
+        ei_class, ei_data = struct.unpack_from("BB", self.file_header, 4)
+        logger.debug("ei_class: 0x%02x ei_data: 0x%02x", ei_class, ei_data)
+        if ei_class == 1:
+            self.bitness = 32
+        elif ei_class == 2:
+            self.bitness = 64
+        else:
+            raise CorruptElfFile("invalid ei_class: 0x%02x" % ei_class)
+
+        if ei_data == 1:
+            self.endian = "<"
+        elif ei_data == 2:
+            self.endian = ">"
+        else:
+            raise CorruptElfFile("not an ELF file: invalid ei_data: 0x%02x" % ei_data)
+
+        if self.bitness == 32:
+            e_phoff, e_shoff = struct.unpack_from(self.endian + "II", self.file_header, 0x1C)
+            self.e_phentsize, self.e_phnum = struct.unpack_from(self.endian + "HH", self.file_header, 0x2A)
+            self.e_shentsize, self.e_shnum = struct.unpack_from(self.endian + "HH", self.file_header, 0x2E)
+        elif self.bitness == 64:
+            e_phoff, e_shoff = struct.unpack_from(self.endian + "QQ", self.file_header, 0x20)
+            self.e_phentsize, self.e_phnum = struct.unpack_from(self.endian + "HH", self.file_header, 0x36)
+            self.e_shentsize, self.e_shnum = struct.unpack_from(self.endian + "HH", self.file_header, 0x3A)
+        else:
+            raise NotImplementedError()
+
+        logger.debug("e_phoff: 0x%02x e_phentsize: 0x%02x e_phnum: %d", e_phoff, self.e_phentsize, self.e_phnum)
+
+        self.f.seek(e_phoff)
+        program_header_size = self.e_phnum * self.e_phentsize
+        self.phbuf = self.f.read(program_header_size)
+        if len(self.phbuf) != program_header_size:
+            logger.warning("failed to read program headers")
+            self.e_phnum = 0
+
+        self.f.seek(e_shoff)
+        section_header_size = self.e_shnum * self.e_shentsize
+        self.shbuf = self.f.read(section_header_size)
+        if len(self.shbuf) != section_header_size:
+            logger.warning("failed to read section headers")
+            self.e_shnum = 0
 
-    (ei_osabi,) = struct.unpack_from(endian + "B", file_header, 7)
     OSABI = {
         # via pyelftools: https://github.com/eliben/pyelftools/blob/0664de05ed2db3d39041e2d51d19622a8ef4fb0f/elftools/elf/enums.py#L35-L58
         # some candidates are commented out because the are not useful values,
@@ -133,218 +184,598 @@ def detect_elf_os(f) -> str:
         # 97: "ARM",          # not an OS
         # 255: "STANDALONE",  # not an OS
     }
-    logger.debug("ei_osabi: 0x%02x (%s)", ei_osabi, OSABI.get(ei_osabi, "unknown"))
 
-    # os_osabi == 0 is commonly set even when the OS is not SYSV.
-    # other values are unused or unknown.
-    if ei_osabi in OSABI and ei_osabi != 0x0:
-        # subsequent strategies may overwrite this value
-        ret = OSABI[ei_osabi]
+    @property
+    def ei_osabi(self) -> Optional[OS]:
+        (ei_osabi,) = struct.unpack_from(self.endian + "B", self.file_header, 7)
+        return ELF.OSABI.get(ei_osabi)
 
-    f.seek(e_phoff)
-    program_header_size = e_phnum * e_phentsize
-    program_headers = f.read(program_header_size)
-    if len(program_headers) != program_header_size:
-        logger.warning("failed to read program headers")
-        e_phnum = 0
+    MACHINE = {
+        # via https://refspecs.linuxfoundation.org/elf/gabi4+/ch4.eheader.html
+        1: "M32",
+        2: "SPARC",
+        3: "i386",
+        4: "68K",
+        5: "88K",
+        6: "486",
+        7: "860",
+        8: "MIPS",
+        9: "S370",
+        10: "MIPS_RS3_LE",
+        11: "RS6000",
+        15: "PA_RISC",
+        16: "nCUBE",
+        17: "VPP500",
+        18: "SPARC32PLUS",
+        19: "960",
+        20: "PPC",
+        21: "PPC64",
+        22: "S390",
+        23: "SPU",
+        36: "V800",
+        37: "FR20",
+        38: "RH32",
+        39: "RCE",
+        40: "ARM",
+        41: "ALPHA",
+        42: "SH",
+        43: "SPARCV9",
+        44: "TRICORE",
+        45: "ARC",
+        46: "H8_300",
+        47: "H8_300H",
+        48: "H8S",
+        49: "H8_500",
+        50: "IA_64",
+        51: "MIPS_X",
+        52: "COLDFIRE",
+        53: "68HC12",
+        54: "MMA",
+        55: "PCP",
+        56: "NCPU",
+        57: "NDR1",
+        58: "STARCORE",
+        59: "ME16",
+        60: "ST100",
+        61: "TINYJ",
+        62: "amd64",
+        63: "PDSP",
+        64: "PDP10",
+        65: "PDP11",
+        66: "FX66",
+        67: "ST9PLUS",
+        68: "ST7",
+        69: "68HC16",
+        70: "68HC11",
+        71: "68HC08",
+        72: "68HC05",
+        73: "SVX",
+        74: "ST19",
+        75: "VAX",
+        76: "CRIS",
+        77: "JAVELIN",
+        78: "FIREPATH",
+        79: "ZSP",
+        80: "MMIX",
+        81: "HUANY",
+        82: "PRISM",
+        83: "AVR",
+        84: "FR30",
+        85: "D10V",
+        86: "D30V",
+        87: "V850",
+        88: "M32R",
+        89: "MN10300",
+        90: "MN10200",
+        91: "PJ",
+        92: "OPENRISC",
+        93: "ARC_A5",
+        94: "XTENSA",
+        95: "VIDEOCORE",
+        96: "TMM_GPP",
+        97: "NS32K",
+        98: "TPC",
+        99: "SNP1K",
+        100: "ST200",
+    }
 
-    # search for PT_NOTE sections that specify an OS
-    # for example, on Linux there is a GNU section with minimum kernel version
-    for i in range(e_phnum):
-        offset = i * e_phentsize
-        phent = program_headers[offset : offset + e_phentsize]
+    @property
+    def e_machine(self) -> Optional[str]:
+        (e_machine,) = struct.unpack_from(self.endian + "H", self.file_header, 0x12)
+        return ELF.MACHINE.get(e_machine)
 
-        PT_NOTE = 0x4
+    def parse_program_header(self, i) -> Phdr:
+        phent_offset = i * self.e_phentsize
+        phent = self.phbuf[phent_offset : phent_offset + self.e_phentsize]
 
-        (p_type,) = struct.unpack_from(endian + "I", phent, 0x0)
+        (p_type,) = struct.unpack_from(self.endian + "I", phent, 0x0)
         logger.debug("ph:p_type: 0x%04x", p_type)
-        if p_type != PT_NOTE:
-            continue
 
-        if bitness == 32:
-            p_offset, _, _, p_filesz = struct.unpack_from(endian + "IIII", phent, 0x4)
-        elif bitness == 64:
-            p_offset, _, _, p_filesz = struct.unpack_from(endian + "QQQQ", phent, 0x8)
+        if self.bitness == 32:
+            p_offset, p_vaddr, p_paddr, p_filesz = struct.unpack_from(self.endian + "IIII", phent, 0x4)
+        elif self.bitness == 64:
+            p_offset, p_vaddr, p_paddr, p_filesz = struct.unpack_from(self.endian + "QQQQ", phent, 0x8)
         else:
             raise NotImplementedError()
 
         logger.debug("ph:p_offset: 0x%02x p_filesz: 0x%04x", p_offset, p_filesz)
 
-        f.seek(p_offset)
-        note = f.read(p_filesz)
-        if len(note) != p_filesz:
-            logger.warning("failed to read note content")
-            continue
+        self.f.seek(p_offset)
+        buf = self.f.read(p_filesz)
+        if len(buf) != p_filesz:
+            raise ValueError("failed to read program header content")
 
-        namesz, descsz, type_ = struct.unpack_from(endian + "III", note, 0x0)
-        name_offset = 0xC
-        desc_offset = name_offset + align(namesz, 0x4)
+        return Phdr(p_type, p_offset, p_vaddr, p_paddr, p_filesz, buf)
 
-        logger.debug("ph:namesz: 0x%02x descsz: 0x%02x type: 0x%04x", namesz, descsz, type_)
-
-        name = note[name_offset : name_offset + namesz].partition(b"\x00")[0].decode("ascii")
-        logger.debug("name: %s", name)
-
-        if type_ != 1:
-            continue
-
-        if name == "GNU":
-            if descsz < 16:
+    @property
+    def program_headers(self):
+        for i in range(self.e_phnum):
+            try:
+                yield self.parse_program_header(i)
+            except ValueError:
                 continue
 
-            desc = note[desc_offset : desc_offset + descsz]
-            abi_tag, kmajor, kminor, kpatch = struct.unpack_from(endian + "IIII", desc, 0x0)
-            logger.debug("GNU_ABI_TAG: 0x%02x", abi_tag)
+    def parse_section_header(self, i) -> Shdr:
+        shent_offset = i * self.e_shentsize
+        shent = self.shbuf[shent_offset : shent_offset + self.e_shentsize]
 
-            if abi_tag in GNU_ABI_TAG:
-                # update only if not set
-                # so we can get the debugging output of subsequent strategies
-                ret = GNU_ABI_TAG[abi_tag] if not ret else ret
-                logger.debug("abi tag: %s earliest compatible kernel: %d.%d.%d", ret, kmajor, kminor, kpatch)
-        elif name == "OpenBSD":
-            logger.debug("note owner: %s", "OPENBSD")
-            ret = OS.OPENBSD if not ret else ret
-        elif name == "NetBSD":
-            logger.debug("note owner: %s", "NETBSD")
-            ret = OS.NETBSD if not ret else ret
-        elif name == "FreeBSD":
-            logger.debug("note owner: %s", "FREEBSD")
-            ret = OS.FREEBSD if not ret else ret
-
-    # search for recognizable dynamic linkers (interpreters)
-    # for example, on linux, we see file paths like: /lib64/ld-linux-x86-64.so.2
-    for i in range(e_phnum):
-        offset = i * e_phentsize
-        phent = program_headers[offset : offset + e_phentsize]
-
-        PT_INTERP = 0x3
-
-        (p_type,) = struct.unpack_from(endian + "I", phent, 0x0)
-        if p_type != PT_INTERP:
-            continue
-
-        if bitness == 32:
-            p_offset, _, _, p_filesz = struct.unpack_from(endian + "IIII", phent, 0x4)
-        elif bitness == 64:
-            p_offset, _, _, p_filesz = struct.unpack_from(endian + "QQQQ", phent, 0x8)
+        if self.bitness == 32:
+            sh_name, sh_type, sh_flags, sh_addr, sh_offset, sh_size, sh_link = struct.unpack_from(
+                self.endian + "IIIIIII", shent, 0x0
+            )
+        elif self.bitness == 64:
+            sh_name, sh_type, sh_flags, sh_addr, sh_offset, sh_size, sh_link = struct.unpack_from(
+                self.endian + "IIQQQQI", shent, 0x0
+            )
         else:
             raise NotImplementedError()
 
-        f.seek(p_offset)
-        interp = f.read(p_filesz)
-        if len(interp) != p_filesz:
-            logger.warning("failed to read interp content")
-            continue
-
-        linker = interp.partition(b"\x00")[0].decode("ascii")
-        logger.debug("linker: %s", linker)
-        if "ld-linux" in linker:
-            # update only if not set
-            # so we can get the debugging output of subsequent strategies
-            ret = OS.LINUX if ret is None else ret
-
-    f.seek(e_shoff)
-    section_header_size = e_shnum * e_shentsize
-    section_headers = f.read(section_header_size)
-    if len(section_headers) != section_header_size:
-        logger.warning("failed to read section headers")
-        e_shnum = 0
-
-    # search for notes stored in sections that aren't visible in program headers.
-    # e.g. .note.Linux in Linux kernel modules.
-    for i in range(e_shnum):
-        offset = i * e_shentsize
-        shent = section_headers[offset : offset + e_shentsize]
-
-        if bitness == 32:
-            sh_name, sh_type, _, sh_addr, sh_offset, sh_size = struct.unpack_from(endian + "IIIIII", shent, 0x0)
-        elif bitness == 64:
-            sh_name, sh_type, _, sh_addr, sh_offset, sh_size = struct.unpack_from(endian + "IIQQQQ", shent, 0x0)
-        else:
-            raise NotImplementedError()
-
-        SHT_NOTE = 0x7
-        if sh_type != SHT_NOTE:
-            continue
-
         logger.debug("sh:sh_offset: 0x%02x sh_size: 0x%04x", sh_offset, sh_size)
 
-        f.seek(sh_offset)
-        note = f.read(sh_size)
-        if len(note) != sh_size:
-            logger.warning("failed to read note content")
-            continue
+        self.f.seek(sh_offset)
+        buf = self.f.read(sh_size)
+        if len(buf) != sh_size:
+            raise ValueError("failed to read section header content")
 
-        namesz, descsz, type_ = struct.unpack_from(endian + "III", note, 0x0)
-        name_offset = 0xC
-        desc_offset = name_offset + align(namesz, 0x4)
+        return Shdr(sh_name, sh_type, sh_flags, sh_addr, sh_offset, sh_size, sh_link, buf)
 
-        logger.debug("sh:namesz: 0x%02x descsz: 0x%02x type: 0x%04x", namesz, descsz, type_)
-
-        name = note[name_offset : name_offset + namesz].partition(b"\x00")[0].decode("ascii")
-        logger.debug("name: %s", name)
-
-        if name == "Linux":
-            logger.debug("note owner: %s", "LINUX")
-            ret = OS.LINUX if not ret else ret
-        elif name == "OpenBSD":
-            logger.debug("note owner: %s", "OPENBSD")
-            ret = OS.OPENBSD if not ret else ret
-        elif name == "NetBSD":
-            logger.debug("note owner: %s", "NETBSD")
-            ret = OS.NETBSD if not ret else ret
-        elif name == "FreeBSD":
-            logger.debug("note owner: %s", "FREEBSD")
-            ret = OS.FREEBSD if not ret else ret
-        elif name == "GNU":
-            if descsz < 16:
+    @property
+    def section_headers(self):
+        for i in range(self.e_shnum):
+            try:
+                yield self.parse_section_header(i)
+            except ValueError:
                 continue
 
-            desc = note[desc_offset : desc_offset + descsz]
-            abi_tag, kmajor, kminor, kpatch = struct.unpack_from(endian + "IIII", desc, 0x0)
-            logger.debug("GNU_ABI_TAG: 0x%02x", abi_tag)
+    @property
+    def linker(self):
+        PT_INTERP = 0x3
+        for phdr in self.program_headers:
+            if phdr.type != PT_INTERP:
+                continue
 
-            if abi_tag in GNU_ABI_TAG:
-                # update only if not set
-                # so we can get the debugging output of subsequent strategies
-                ret = GNU_ABI_TAG[abi_tag] if not ret else ret
-                logger.debug("abi tag: %s earliest compatible kernel: %d.%d.%d", ret, kmajor, kminor, kpatch)
+            return read_cstr(phdr.buf, 0)
+
+    @property
+    def versions_needed(self) -> Dict[str, Set[str]]:
+        # symbol version requirements are stored in the .gnu.version_r section,
+        # which has type SHT_GNU_verneed (0x6ffffffe).
+        #
+        # this contains a linked list of ElfXX_Verneed structs,
+        # each referencing a linked list of ElfXX_Vernaux structs.
+        # strings are stored in the section referenced by the sh_link field of the section header.
+        # each Verneed struct contains a reference to the name of the library,
+        # each Vernaux struct contains a reference to the name of a symbol.
+        SHT_GNU_VERNEED = 0x6FFFFFFE
+        for shdr in self.section_headers:
+            if shdr.type != SHT_GNU_VERNEED:
+                continue
+
+            # the linked section contains strings referenced by the verneed structures.
+            linked_shdr = self.parse_section_header(shdr.link)
+
+            versions_needed = collections.defaultdict(set)
+
+            # read verneed structures from the start of the section
+            # until the vn_next link is 0x0.
+            # each entry describes a shared object that is required by this binary.
+            vn_offset = 0x0
+            while True:
+                # ElfXX_Verneed layout is the same on 32 and 64 bit
+                vn_version, vn_cnt, vn_file, vn_aux, vn_next = struct.unpack_from(
+                    self.endian + "HHIII", shdr.buf, vn_offset
+                )
+                if vn_version != 1:
+                    # unexpected format, don't try to keep parsing
+                    break
+
+                # shared object names, like: "libdl.so.2"
+                so_name = read_cstr(linked_shdr.buf, vn_file)
+
+                # read vernaux structures linked from the verneed structure.
+                # there should be vn_cnt of these.
+                # each entry describes an ABI name required by the shared object.
+                vna_offset = vn_offset + vn_aux
+                for i in range(vn_cnt):
+                    # ElfXX_Vernaux layout is the same on 32 and 64 bit
+                    _, _, _, vna_name, vna_next = struct.unpack_from(self.endian + "IHHII", shdr.buf, vna_offset)
+
+                    # ABI names, like: "GLIBC_2.2.5"
+                    abi = read_cstr(linked_shdr.buf, vna_name)
+                    versions_needed[so_name].add(abi)
+
+                    vna_offset += vna_next
+
+                vn_offset += vn_next
+                if vn_next == 0:
+                    break
+
+            return dict(versions_needed)
+
+        return {}
+
+    @property
+    def dynamic_entries(self) -> Iterator[Tuple[int, int]]:
+        """
+        read the entries from the dynamic section,
+        yielding the tag and value for each entry.
+        """
+        DT_NULL = 0x0
+        PT_DYNAMIC = 0x2
+        for phdr in self.program_headers:
+            if phdr.type != PT_DYNAMIC:
+                continue
+
+            offset = 0x0
+            while True:
+                if self.bitness == 32:
+                    d_tag, d_val = struct.unpack_from(self.endian + "II", phdr.buf, offset)
+                    offset += 8
+                elif self.bitness == 64:
+                    d_tag, d_val = struct.unpack_from(self.endian + "QQ", phdr.buf, offset)
+                    offset += 16
+                else:
+                    raise NotImplementedError()
+
+                if d_tag == DT_NULL:
+                    break
+
+                yield d_tag, d_val
+
+    @property
+    def strtab(self) -> Optional[bytes]:
+        """
+        fetch the bytes of the string table
+        referenced by the dynamic section.
+        """
+        DT_STRTAB = 0x5
+        DT_STRSZ = 0xA
+
+        strtab_addr = None
+        strtab_size = None
+
+        for d_tag, d_val in self.dynamic_entries:
+            if d_tag == DT_STRTAB:
+                strtab_addr = d_val
+
+        for d_tag, d_val in self.dynamic_entries:
+            if d_tag == DT_STRSZ:
+                strtab_size = d_val
+
+        if strtab_addr is None:
+            return None
+
+        if strtab_size is None:
+            return None
+
+        strtab_offset = None
+        for shdr in self.section_headers:
+            if shdr.addr <= strtab_addr < shdr.addr + shdr.size:
+                strtab_offset = shdr.offset + (strtab_addr - shdr.addr)
+
+        if strtab_offset is None:
+            return None
+
+        self.f.seek(strtab_offset)
+        strtab_buf = self.f.read(strtab_size)
+
+        if len(strtab_buf) != strtab_size:
+            return None
+
+        return strtab_buf
+
+    @property
+    def needed(self) -> Iterator[str]:
+        """
+        read the names of DT_NEEDED entries from the dynamic section,
+        which correspond to dependencies on other shared objects,
+        like: `libpthread.so.0`
+        """
+        DT_NEEDED = 0x1
+        strtab = self.strtab
+        if not strtab:
+            return
+
+        for d_tag, d_val in self.dynamic_entries:
+            if d_tag != DT_NEEDED:
+                continue
+
+            yield read_cstr(strtab, d_val)
+
+
+@dataclass
+class ABITag:
+    os: OS
+    kmajor: int
+    kminor: int
+    kpatch: int
+
+
+class PHNote:
+    def __init__(self, endian: str, buf: bytes):
+        self.endian = endian
+        self.buf = buf
+
+        # these will be initialized in `_parse()`
+        self.type_: int
+        self.descsz: int
+        self.name: str
+
+        self._parse()
+
+    def _parse(self):
+        namesz, self.descsz, self.type_ = struct.unpack_from(self.endian + "III", self.buf, 0x0)
+        name_offset = 0xC
+        self.desc_offset = name_offset + align(namesz, 0x4)
+
+        logger.debug("ph:namesz: 0x%02x descsz: 0x%02x type: 0x%04x", namesz, self.descsz, self.type_)
+
+        self.name = self.buf[name_offset : name_offset + namesz].partition(b"\x00")[0].decode("ascii")
+        logger.debug("name: %s", self.name)
+
+    @property
+    def abi_tag(self) -> Optional[ABITag]:
+        if self.type_ != 1:
+            # > The type field shall be 1.
+            # Linux Standard Base Specification 1.2
+            # ref: https://refspecs.linuxfoundation.org/LSB_1.2.0/gLSB/noteabitag.html
+            return None
+
+        if self.name != "GNU":
+            return None
+
+        if self.descsz < 16:
+            return None
+
+        desc = self.buf[self.desc_offset : self.desc_offset + self.descsz]
+        abi_tag, kmajor, kminor, kpatch = struct.unpack_from(self.endian + "IIII", desc, 0x0)
+        logger.debug("GNU_ABI_TAG: 0x%02x", abi_tag)
+
+        os = GNU_ABI_TAG.get(abi_tag)
+        if not os:
+            return None
+
+        logger.debug("abi tag: %s earliest compatible kernel: %d.%d.%d", os, kmajor, kminor, kpatch)
+
+        return ABITag(os, kmajor, kminor, kpatch)
+
+
+class SHNote:
+    def __init__(self, endian: str, buf: bytes):
+        self.endian = endian
+        self.buf = buf
+
+        # these will be initialized in `_parse()`
+        self.type_: int
+        self.descsz: int
+        self.name: str
+
+        self._parse()
+
+    def _parse(self):
+        namesz, self.descsz, self.type_ = struct.unpack_from(self.endian + "III", self.buf, 0x0)
+        name_offset = 0xC
+        self.desc_offset = name_offset + align(namesz, 0x4)
+
+        logger.debug("sh:namesz: 0x%02x descsz: 0x%02x type: 0x%04x", namesz, self.descsz, self.type_)
+
+        name_buf = self.buf[name_offset : name_offset + namesz]
+        self.name = read_cstr(name_buf, 0x0)
+        logger.debug("sh:name: %s", self.name)
+
+    @property
+    def abi_tag(self) -> Optional[ABITag]:
+        if self.name != "GNU":
+            return None
+
+        if self.descsz < 16:
+            return None
+
+        desc = self.buf[self.desc_offset : self.desc_offset + self.descsz]
+        abi_tag, kmajor, kminor, kpatch = struct.unpack_from(self.endian + "IIII", desc, 0x0)
+        logger.debug("GNU_ABI_TAG: 0x%02x", abi_tag)
+
+        os = GNU_ABI_TAG.get(abi_tag)
+        if not os:
+            return None
+
+        logger.debug("abi tag: %s earliest compatible kernel: %d.%d.%d", os, kmajor, kminor, kpatch)
+        return ABITag(os, kmajor, kminor, kpatch)
+
+
+def guess_os_from_osabi(elf) -> Optional[OS]:
+    return elf.ei_osabi
+
+
+def guess_os_from_ph_notes(elf) -> Optional[OS]:
+    # search for PT_NOTE sections that specify an OS
+    # for example, on Linux there is a GNU section with minimum kernel version
+    PT_NOTE = 0x4
+    for phdr in elf.program_headers:
+        if phdr.type != PT_NOTE:
+            continue
+
+        note = PHNote(elf.endian, phdr.buf)
+
+        if note.type_ != 1:
+            # > The type field shall be 1.
+            # Linux Standard Base Specification 1.2
+            # ref: https://refspecs.linuxfoundation.org/LSB_1.2.0/gLSB/noteabitag.html
+            continue
+
+        if note.name == "Linux":
+            logger.debug("note owner: %s", "LINUX")
+            return OS.LINUX
+        elif note.name == "OpenBSD":
+            logger.debug("note owner: %s", "OPENBSD")
+            return OS.OPENBSD
+        elif note.name == "NetBSD":
+            logger.debug("note owner: %s", "NETBSD")
+            return OS.NETBSD
+        elif note.name == "FreeBSD":
+            logger.debug("note owner: %s", "FREEBSD")
+            return OS.FREEBSD
+        elif note.name == "GNU":
+            abi_tag = note.abi_tag
+            if abi_tag:
+                return abi_tag.os
+            else:
+                # cannot make a guess about the OS, but probably linux or hurd
+                pass
+
+    return None
+
+
+def guess_os_from_sh_notes(elf) -> Optional[OS]:
+    # search for notes stored in sections that aren't visible in program headers.
+    # e.g. .note.Linux in Linux kernel modules.
+    SHT_NOTE = 0x7
+    for shdr in elf.section_headers:
+        if shdr.type != SHT_NOTE:
+            continue
+
+        note = SHNote(elf.endian, shdr.buf)
+
+        if note.name == "Linux":
+            logger.debug("note owner: %s", "LINUX")
+            return OS.LINUX
+        elif note.name == "OpenBSD":
+            logger.debug("note owner: %s", "OPENBSD")
+            return OS.OPENBSD
+        elif note.name == "NetBSD":
+            logger.debug("note owner: %s", "NETBSD")
+            return OS.NETBSD
+        elif note.name == "FreeBSD":
+            logger.debug("note owner: %s", "FREEBSD")
+            return OS.FREEBSD
+        elif note.name == "GNU":
+            abi_tag = note.abi_tag
+            if abi_tag:
+                return abi_tag.os
+            else:
+                # cannot make a guess about the OS, but probably linux or hurd
+                pass
+
+    return None
+
+
+def guess_os_from_linker(elf) -> Optional[OS]:
+    # search for recognizable dynamic linkers (interpreters)
+    # for example, on linux, we see file paths like: /lib64/ld-linux-x86-64.so.2
+    linker = elf.linker
+    if linker and "ld-linux" in elf.linker:
+        return OS.LINUX
+
+    return None
+
+
+def guess_os_from_abi_versions_needed(elf) -> Optional[OS]:
+    # then lets look for GLIBC symbol versioning requirements.
+    # this will let us guess about linux/hurd in some cases.
+
+    versions_needed = elf.versions_needed
+    if any(map(lambda abi: abi.startswith("GLIBC"), itertools.chain(*versions_needed.values()))):
+        # there are any GLIBC versions needed
+
+        if elf.e_machine != "i386":
+            # GLIBC runs on Linux and Hurd.
+            # for Hurd, its *only* on i386.
+            # so if we're not on i386, then we're on Linux.
+            return OS.LINUX
+
+        else:
+            # we're on i386, so we could be on either Linux or Hurd.
+            linker = elf.linker
+
+            if linker and "ld-linux" in linker:
+                return OS.LINUX
+
+            elif linker and "/ld.so" in linker:
+                return OS.HURD
+
+            else:
+                # we don't have any good guesses based on versions needed
+                pass
+
+    return None
+
+
+def guess_os_from_needed_dependencies(elf) -> Optional[OS]:
+    for needed in elf.needed:
+        if needed.startswith("libmachuser.so"):
+            return OS.HURD
+        if needed.startswith("libhurduser.so"):
+            return OS.HURD
+
+    return None
+
+
+def detect_elf_os(f) -> str:
+    """
+    f: type Union[BinaryIO, IDAIO]
+    """
+    elf = ELF(f)
+
+    osabi_guess = guess_os_from_osabi(elf)
+    logger.debug("guess: osabi: %s", osabi_guess)
+
+    ph_notes_guess = guess_os_from_ph_notes(elf)
+    logger.debug("guess: ph notes: %s", ph_notes_guess)
+
+    sh_notes_guess = guess_os_from_sh_notes(elf)
+    logger.debug("guess: sh notes: %s", sh_notes_guess)
+
+    linker_guess = guess_os_from_linker(elf)
+    logger.debug("guess: linker: %s", linker_guess)
+
+    abi_versions_needed_guess = guess_os_from_abi_versions_needed(elf)
+    logger.debug("guess: ABI versions needed: %s", abi_versions_needed_guess)
+
+    needed_dependencies_guess = guess_os_from_needed_dependencies(elf)
+    logger.debug("guess: needed dependencies: %s", needed_dependencies_guess)
+
+    ret = None
+
+    if osabi_guess:
+        ret = osabi_guess
+
+    elif ph_notes_guess:
+        ret = ph_notes_guess
+
+    elif sh_notes_guess:
+        ret = sh_notes_guess
+
+    elif linker_guess:
+        ret = linker_guess
+
+    elif abi_versions_needed_guess:
+        ret = abi_versions_needed_guess
+
+    elif needed_dependencies_guess:
+        ret = needed_dependencies_guess
 
     return ret.value if ret is not None else "unknown"
 
 
-class Arch(str, Enum):
-    I386 = "i386"
-    AMD64 = "amd64"
-
-
 def detect_elf_arch(f: BinaryIO) -> str:
-    f.seek(0x0)
-    file_header = f.read(0x40)
-
-    if not file_header.startswith(b"\x7fELF"):
-        raise CorruptElfFile("missing magic header")
-
-    (ei_data,) = struct.unpack_from("B", file_header, 5)
-    logger.debug("ei_data: 0x%02x", ei_data)
-
-    if ei_data == 1:
-        endian = "<"
-    elif ei_data == 2:
-        endian = ">"
-    else:
-        raise CorruptElfFile("not an ELF file: invalid ei_data: 0x%02x" % ei_data)
-
-    (ei_machine,) = struct.unpack_from(endian + "H", file_header, 0x12)
-    logger.debug("ei_machine: 0x%02x", ei_machine)
-
-    EM_386 = 0x3
-    EM_X86_64 = 0x3E
-    if ei_machine == EM_386:
-        return Arch.I386
-    elif ei_machine == EM_X86_64:
-        return Arch.AMD64
-    else:
-        # not really unknown, but unsupport at the moment:
-        # https://github.com/eliben/pyelftools/blob/ab444d982d1849191e910299a985989857466620/elftools/elf/enums.py#L73
-        return "unknown"
+    return ELF(f).e_machine or "unknown"

capa/features/extractors/elffile.py

@@ -7,7 +7,6 @@
 # See the License for the specific language governing permissions and limitations under the License.
 import io
 import logging
-import contextlib
 from typing import Tuple, Iterator
 
 from elftools.elf.elffile import ELFFile, SymbolTableSection
@@ -16,7 +15,6 @@ import capa.features.extractors.common
 from capa.features.file import Import, Section
 from capa.features.common import OS, FORMAT_ELF, Arch, Format, Feature
 from capa.features.address import NO_ADDRESS, FileOffsetAddress, AbsoluteVirtualAddress
-from capa.features.extractors.elf import Arch as ElfArch
 from capa.features.extractors.base_extractor import FeatureExtractor
 
 logger = logging.getLogger(__name__)
@@ -26,17 +24,17 @@ def extract_file_import_names(elf, **kwargs):
     # see https://github.com/eliben/pyelftools/blob/0664de05ed2db3d39041e2d51d19622a8ef4fb0f/scripts/readelf.py#L372
     symbol_tables = [(idx, s) for idx, s in enumerate(elf.iter_sections()) if isinstance(s, SymbolTableSection)]
 
-    for section_index, section in symbol_tables:
+    for _, section in symbol_tables:
         if not isinstance(section, SymbolTableSection):
             continue
 
         if section["sh_entsize"] == 0:
-            logger.debug("Symbol table '%s' has a sh_entsize of zero!" % (section.name))
+            logger.debug("Symbol table '%s' has a sh_entsize of zero!", section.name)
             continue
 
-        logger.debug("Symbol table '%s' contains %s entries:" % (section.name, section.num_symbols()))
+        logger.debug("Symbol table '%s' contains %s entries:", section.name, section.num_symbols())
 
-        for nsym, symbol in enumerate(section.iter_symbols()):
+        for _, symbol in enumerate(section.iter_symbols()):
             if symbol.name and symbol.entry.st_info.type == "STT_FUNC":
                 # TODO symbol address
                 # TODO symbol version info?
@@ -73,9 +71,9 @@ def extract_file_arch(elf, **kwargs):
     # TODO merge with capa.features.extractors.elf.detect_elf_arch()
     arch = elf.get_machine_arch()
     if arch == "x86":
-        yield Arch(ElfArch.I386), NO_ADDRESS
+        yield Arch("i386"), NO_ADDRESS
     elif arch == "x64":
-        yield Arch(ElfArch.AMD64), NO_ADDRESS
+        yield Arch("amd64"), NO_ADDRESS
     else:
         logger.warning("unsupported architecture: %s", arch)
 
@@ -110,7 +108,7 @@ GLOBAL_HANDLERS = (
 
 class ElfFeatureExtractor(FeatureExtractor):
     def __init__(self, path: str):
-        super(ElfFeatureExtractor, self).__init__()
+        super().__init__()
         self.path = path
         with open(self.path, "rb") as f:
             self.elf = ELFFile(io.BytesIO(f.read()))
@@ -153,8 +151,8 @@ class ElfFeatureExtractor(FeatureExtractor):
     def extract_insn_features(self, f, bb, insn):
         raise NotImplementedError("ElfFeatureExtractor can only be used to extract file features")
 
-    def is_library_function(self, va):
+    def is_library_function(self, addr):
         raise NotImplementedError("ElfFeatureExtractor can only be used to extract file features")
 
-    def get_function_name(self, va):
+    def get_function_name(self, addr):
         raise NotImplementedError("ElfFeatureExtractor can only be used to extract file features")

capa/features/extractors/helpers.py

@@ -112,7 +112,6 @@ def carve_pe(pbytes: bytes, offset: int = 0) -> Iterator[Tuple[int, int]]:
     todo = [(off, mzx, pex, key) for (off, mzx, pex, key) in todo if off != -1]
 
     while len(todo):
-
         off, mzx, pex, key = todo.pop()
 
         # The MZ header has one field we will check

capa/features/extractors/ida/basicblock.py

@@ -95,7 +95,7 @@ def extract_bb_tight_loop(fh: FunctionHandle, bbh: BBHandle) -> Iterator[Tuple[F
 def extract_features(fh: FunctionHandle, bbh: BBHandle) -> Iterator[Tuple[Feature, Address]]:
     """extract basic block features"""
     for bb_handler in BASIC_BLOCK_HANDLERS:
-        for (feature, addr) in bb_handler(fh, bbh):
+        for feature, addr in bb_handler(fh, bbh):
             yield feature, addr
     yield BasicBlock(), bbh.address
 

capa/features/extractors/ida/extractor.py

@@ -23,8 +23,9 @@ from capa.features.extractors.base_extractor import BBHandle, InsnHandle, Functi
 
 class IdaFeatureExtractor(FeatureExtractor):
     def __init__(self):
-        super(IdaFeatureExtractor, self).__init__()
+        super().__init__()
         self.global_features: List[Tuple[Feature, Address]] = []
+        self.global_features.extend(capa.features.extractors.ida.file.extract_file_format())
         self.global_features.extend(capa.features.extractors.ida.global_.extract_os())
         self.global_features.extend(capa.features.extractors.ida.global_.extract_arch())
 

capa/features/extractors/ida/file.py

@@ -39,7 +39,7 @@ def check_segment_for_pe(seg: idaapi.segment_t) -> Iterator[Tuple[int, int]]:
     ]
 
     todo = []
-    for (mzx, pex, i) in mz_xor:
+    for mzx, pex, i in mz_xor:
         for off in capa.features.extractors.ida.helpers.find_byte_sequence(seg.start_ea, seg.end_ea, mzx):
             todo.append((off, mzx, pex, i))
 
@@ -73,13 +73,13 @@ def extract_file_embedded_pe() -> Iterator[Tuple[Feature, Address]]:
         - Check 'Load resource sections' when opening binary in IDA manually
     """
     for seg in capa.features.extractors.ida.helpers.get_segments(skip_header_segments=True):
-        for (ea, _) in check_segment_for_pe(seg):
+        for ea, _ in check_segment_for_pe(seg):
             yield Characteristic("embedded pe"), FileOffsetAddress(ea)
 
 
 def extract_file_export_names() -> Iterator[Tuple[Feature, Address]]:
     """extract function exports"""
-    for (_, _, ea, name) in idautils.Entries():
+    for _, _, ea, name in idautils.Entries():
         yield Export(name), AbsoluteVirtualAddress(ea)
 
 
@@ -94,7 +94,7 @@ def extract_file_import_names() -> Iterator[Tuple[Feature, Address]]:
      - modulename.importname
      - importname
     """
-    for (ea, info) in capa.features.extractors.ida.helpers.get_file_imports().items():
+    for ea, info in capa.features.extractors.ida.helpers.get_file_imports().items():
         addr = AbsoluteVirtualAddress(ea)
         if info[1] and info[2]:
             # e.g. in mimikatz: ('cabinet', 'FCIAddFile', 11L)
@@ -115,6 +115,9 @@ def extract_file_import_names() -> Iterator[Tuple[Feature, Address]]:
         for name in capa.features.extractors.helpers.generate_symbols(dll, symbol):
             yield Import(name), addr
 
+    for ea, info in capa.features.extractors.ida.helpers.get_file_externs().items():
+        yield Import(info[1]), AbsoluteVirtualAddress(ea)
+
 
 def extract_file_section_names() -> Iterator[Tuple[Feature, Address]]:
     """extract section names
@@ -165,7 +168,7 @@ def extract_file_function_names() -> Iterator[Tuple[Feature, Address]]:
 def extract_file_format() -> Iterator[Tuple[Feature, Address]]:
     file_info = idaapi.get_inf_structure()
 
-    if file_info.filetype == idaapi.f_PE:
+    if file_info.filetype in (idaapi.f_PE, idaapi.f_COFF):
         yield Format(FORMAT_PE), NO_ADDRESS
     elif file_info.filetype == idaapi.f_ELF:
         yield Format(FORMAT_ELF), NO_ADDRESS
@@ -173,7 +176,7 @@ def extract_file_format() -> Iterator[Tuple[Feature, Address]]:
         # no file type to return when processing a binary file, but we want to continue processing
         return
     else:
-        raise NotImplementedError("file format: %d" % file_info.filetype)
+        raise NotImplementedError("unexpected file format: %d" % file_info.filetype)
 
 
 def extract_features() -> Iterator[Tuple[Feature, Address]]:

capa/features/extractors/ida/function.py

@@ -45,7 +45,7 @@ def extract_recursive_call(fh: FunctionHandle):
 
 def extract_features(fh: FunctionHandle) -> Iterator[Tuple[Feature, Address]]:
     for func_handler in FUNCTION_HANDLERS:
-        for (feature, addr) in func_handler(fh):
+        for feature, addr in func_handler(fh):
             yield feature, addr
 
 

capa/features/extractors/ida/global_.py

@@ -31,7 +31,7 @@ def extract_os() -> Iterator[Tuple[Feature, Address]]:
         #  2. handling a new file format (e.g. macho)
         #
         # for (1) we can't do much - its shellcode and all bets are off.
-        # we could maybe accept a futher CLI argument to specify the OS,
+        # we could maybe accept a further CLI argument to specify the OS,
         # but i think this would be rarely used.
         # rules that rely on OS conditions will fail to match on shellcode.
         #

capa/features/extractors/ida/helpers.py

@@ -5,12 +5,13 @@
 # Unless required by applicable law or agreed to in writing, software distributed under the License
 #  is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and limitations under the License.
-from typing import Any, Dict, Tuple, Iterator
+from typing import Any, Dict, Tuple, Iterator, Optional
 
 import idc
 import idaapi
 import idautils
 import ida_bytes
+import ida_segment
 
 from capa.features.address import AbsoluteVirtualAddress
 from capa.features.extractors.base_extractor import FunctionHandle
@@ -35,7 +36,7 @@ def find_byte_sequence(start: int, end: int, seq: bytes) -> Iterator[int]:
 
 
 def get_functions(
-    start: int = None, end: int = None, skip_thunks: bool = False, skip_libs: bool = False
+    start: Optional[int] = None, end: Optional[int] = None, skip_thunks: bool = False, skip_libs: bool = False
 ) -> Iterator[FunctionHandle]:
     """get functions, range optional
 
@@ -109,6 +110,19 @@ def get_file_imports() -> Dict[int, Tuple[str, str, int]]:
     return imports
 
 
+def get_file_externs() -> Dict[int, Tuple[str, str, int]]:
+    externs = {}
+
+    for seg in get_segments(skip_header_segments=True):
+        if not (seg.type == ida_segment.SEG_XTRN):
+            continue
+
+        for ea in idautils.Functions(seg.start_ea, seg.end_ea):
+            externs[ea] = ("", idaapi.get_func_name(ea), -1)
+
+    return externs
+
+
 def get_instructions_in_range(start: int, end: int) -> Iterator[idaapi.insn_t]:
     """yield instructions in range
 
@@ -183,7 +197,7 @@ def read_bytes_at(ea: int, count: int) -> bytes:
 def find_string_at(ea: int, min_: int = 4) -> str:
     """check if ASCII string exists at a given virtual address"""
     found = idaapi.get_strlit_contents(ea, -1, idaapi.STRTYPE_C)
-    if found and len(found) > min_:
+    if found and len(found) >= min_:
         try:
             found = found.decode("ascii")
             # hacky check for IDA bug; get_strlit_contents also reads Unicode as
@@ -207,7 +221,8 @@ def get_op_phrase_info(op: idaapi.op_t) -> Dict:
         return {}
 
     scale = 1 << ((op.specflag2 & 0xC0) >> 6)
-    offset = op.addr
+    # IDA ea_t may be 32- or 64-bit; we assume displacement can only be 32-bit
+    offset = op.addr & 0xFFFFFFFF
 
     if op.specflag1 == 0:
         index = None
@@ -273,7 +288,7 @@ def is_frame_register(reg: int) -> bool:
     return reg in (idautils.procregs.sp.reg, idautils.procregs.bp.reg)
 
 
-def get_insn_ops(insn: idaapi.insn_t, target_ops: Tuple[Any] = None) -> idaapi.op_t:
+def get_insn_ops(insn: idaapi.insn_t, target_ops: Optional[Tuple[Any]] = None) -> idaapi.op_t:
     """yield op_t for instruction, filter on type if specified"""
     for op in insn.ops:
         if op.type == idaapi.o_void:

capa/features/extractors/ida/insn.py

@@ -23,13 +23,19 @@ from capa.features.extractors.base_extractor import BBHandle, InsnHandle, Functi
 SECURITY_COOKIE_BYTES_DELTA = 0x40
 
 
-def get_imports(ctx: Dict[str, Any]) -> Dict[str, Any]:
+def get_imports(ctx: Dict[str, Any]) -> Dict[int, Any]:
     if "imports_cache" not in ctx:
         ctx["imports_cache"] = capa.features.extractors.ida.helpers.get_file_imports()
     return ctx["imports_cache"]
 
 
-def check_for_api_call(ctx: Dict[str, Any], insn: idaapi.insn_t) -> Iterator[str]:
+def get_externs(ctx: Dict[str, Any]) -> Dict[int, Any]:
+    if "externs_cache" not in ctx:
+        ctx["externs_cache"] = capa.features.extractors.ida.helpers.get_file_externs()
+    return ctx["externs_cache"]
+
+
+def check_for_api_call(insn: idaapi.insn_t, funcs: Dict[int, Any]) -> Iterator[Any]:
     """check instruction for API call"""
     info = ()
     ref = insn.ea
@@ -46,7 +52,7 @@ def check_for_api_call(ctx: Dict[str, Any], insn: idaapi.insn_t) -> Iterator[str
             except IndexError:
                 break
 
-        info = get_imports(ctx).get(ref, ())
+        info = funcs.get(ref, ())
         if info:
             break
 
@@ -55,7 +61,7 @@ def check_for_api_call(ctx: Dict[str, Any], insn: idaapi.insn_t) -> Iterator[str
             break
 
     if info:
-        yield "%s.%s" % (info[0], info[1])
+        yield info
 
 
 def extract_insn_api_features(fh: FunctionHandle, bbh: BBHandle, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
@@ -70,11 +76,17 @@ def extract_insn_api_features(fh: FunctionHandle, bbh: BBHandle, ih: InsnHandle)
     if not insn.get_canon_mnem() in ("call", "jmp"):
         return
 
-    for api in check_for_api_call(fh.ctx, insn):
-        dll, _, symbol = api.rpartition(".")
-        for name in capa.features.extractors.helpers.generate_symbols(dll, symbol):
+    # check calls to imported functions
+    for api in check_for_api_call(insn, get_imports(fh.ctx)):
+        # tuple (<module>, <function>, <ordinal>)
+        for name in capa.features.extractors.helpers.generate_symbols(api[0], api[1]):
             yield API(name), ih.address
 
+    # check calls to extern functions
+    for api in check_for_api_call(insn, get_externs(fh.ctx)):
+        # tuple (<module>, <function>, <ordinal>)
+        yield API(api[1]), ih.address
+
     # extract IDA/FLIRT recognized API functions
     targets = tuple(idautils.CodeRefsFrom(insn.ea, False))
     if not targets:
@@ -160,7 +172,9 @@ def extract_insn_bytes_features(fh: FunctionHandle, bbh: BBHandle, ih: InsnHandl
     if ref != insn.ea:
         extracted_bytes = capa.features.extractors.ida.helpers.read_bytes_at(ref, MAX_BYTES_FEATURE_SIZE)
         if extracted_bytes and not capa.features.extractors.helpers.all_zeros(extracted_bytes):
-            yield Bytes(extracted_bytes), ih.address
+            if not capa.features.extractors.ida.helpers.find_string_at(insn.ea):
+                # don't extract byte features for obvious strings
+                yield Bytes(extracted_bytes), ih.address
 
 
 def extract_insn_string_features(
@@ -201,7 +215,11 @@ def extract_insn_offset_features(
             continue
 
         p_info = capa.features.extractors.ida.helpers.get_op_phrase_info(op)
-        op_off = p_info.get("offset", 0)
+
+        op_off = p_info.get("offset", None)
+        if op_off is None:
+            continue
+
         if idaapi.is_mapped(op_off):
             # Ignore:
             #   mov esi, dword_1005B148[esi]
@@ -464,7 +482,7 @@ def extract_function_indirect_call_characteristic_features(
 def extract_features(f: FunctionHandle, bbh: BBHandle, insn: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
     """extract instruction features"""
     for inst_handler in INSTRUCTION_HANDLERS:
-        for (feature, ea) in inst_handler(f, bbh, insn):
+        for feature, ea in inst_handler(f, bbh, insn):
             yield feature, ea
 
 

capa/features/extractors/null.py

@@ -52,26 +52,21 @@ class NullFeatureExtractor(FeatureExtractor):
             yield FunctionHandle(address, None)
 
     def extract_function_features(self, f):
-        for address, feature in self.functions.get(f.address, {}).features:
+        for address, feature in self.functions[f.address].features:
             yield feature, address
 
     def get_basic_blocks(self, f):
-        for address in sorted(self.functions.get(f.address, {}).basic_blocks.keys()):
+        for address in sorted(self.functions[f.address].basic_blocks.keys()):
             yield BBHandle(address, None)
 
     def extract_basic_block_features(self, f, bb):
-        for address, feature in self.functions.get(f.address, {}).basic_blocks.get(bb.address, {}).features:
+        for address, feature in self.functions[f.address].basic_blocks[bb.address].features:
             yield feature, address
 
     def get_instructions(self, f, bb):
-        for address in sorted(self.functions.get(f.address, {}).basic_blocks.get(bb.address, {}).instructions.keys()):
+        for address in sorted(self.functions[f.address].basic_blocks[bb.address].instructions.keys()):
             yield InsnHandle(address, None)
 
     def extract_insn_features(self, f, bb, insn):
-        for address, feature in (
-            self.functions.get(f.address, {})
-            .basic_blocks.get(bb.address, {})
-            .instructions.get(insn.address, {})
-            .features
-        ):
+        for address, feature in self.functions[f.address].basic_blocks[bb.address].instructions[insn.address].features:
             yield feature, address

capa/features/extractors/pefile.py

@@ -133,7 +133,8 @@ def extract_file_features(pe, buf):
     """
 
     for file_handler in FILE_HANDLERS:
-        for feature, va in file_handler(pe=pe, buf=buf):
+        # file_handler: type: (pe, bytes) -> Iterable[Tuple[Feature, Address]]
+        for feature, va in file_handler(pe=pe, buf=buf):  # type: ignore
             yield feature, va
 
 
@@ -160,7 +161,8 @@ def extract_global_features(pe, buf):
       Tuple[Feature, VA]: a feature and its location.
     """
     for handler in GLOBAL_HANDLERS:
-        for feature, va in handler(pe=pe, buf=buf):
+        # file_handler: type: (pe, bytes) -> Iterable[Tuple[Feature, Address]]
+        for feature, va in handler(pe=pe, buf=buf):  # type: ignore
             yield feature, va
 
 
@@ -172,7 +174,7 @@ GLOBAL_HANDLERS = (
 
 class PefileFeatureExtractor(FeatureExtractor):
     def __init__(self, path: str):
-        super(PefileFeatureExtractor, self).__init__()
+        super().__init__()
         self.path = path
         self.pe = pefile.PE(path)
 

capa/features/extractors/smda/basicblock.py

@@ -1,133 +0,0 @@
-import string
-import struct
-from typing import Tuple, Iterator
-
-from capa.features.common import Feature, Characteristic
-from capa.features.address import Address
-from capa.features.basicblock import BasicBlock
-from capa.features.extractors.helpers import MIN_STACKSTRING_LEN
-from capa.features.extractors.base_extractor import BBHandle, FunctionHandle
-
-
-def _bb_has_tight_loop(f, bb):
-    """
-    parse tight loops, true if last instruction in basic block branches to bb start
-    """
-    return bb.offset in f.blockrefs[bb.offset] if bb.offset in f.blockrefs else False
-
-
-def extract_bb_tight_loop(f: FunctionHandle, bb: BBHandle) -> Iterator[Tuple[Feature, Address]]:
-    """check basic block for tight loop indicators"""
-    if _bb_has_tight_loop(f.inner, bb.inner):
-        yield Characteristic("tight loop"), bb.address
-
-
-def _bb_has_stackstring(f, bb):
-    """
-    extract potential stackstring creation, using the following heuristics:
-      - basic block contains enough moves of constant bytes to the stack
-    """
-    count = 0
-    for instr in bb.getInstructions():
-        if is_mov_imm_to_stack(instr):
-            count += get_printable_len(instr.getDetailed())
-        if count > MIN_STACKSTRING_LEN:
-            return True
-    return False
-
-
-def get_operands(smda_ins):
-    return [o.strip() for o in smda_ins.operands.split(",")]
-
-
-def extract_stackstring(f: FunctionHandle, bb: BBHandle) -> Iterator[Tuple[Feature, Address]]:
-    """check basic block for stackstring indicators"""
-    if _bb_has_stackstring(f.inner, bb.inner):
-        yield Characteristic("stack string"), bb.address
-
-
-def is_mov_imm_to_stack(smda_ins):
-    """
-    Return if instruction moves immediate onto stack
-    """
-    if not smda_ins.mnemonic.startswith("mov"):
-        return False
-
-    try:
-        dst, src = get_operands(smda_ins)
-    except ValueError:
-        # not two operands
-        return False
-
-    try:
-        int(src, 16)
-    except ValueError:
-        return False
-
-    if not any(regname in dst for regname in ["ebp", "rbp", "esp", "rsp"]):
-        return False
-
-    return True
-
-
-def is_printable_ascii(chars):
-    return all(c < 127 and chr(c) in string.printable for c in chars)
-
-
-def is_printable_utf16le(chars):
-    if all(c == 0x00 for c in chars[1::2]):
-        return is_printable_ascii(chars[::2])
-
-
-def get_printable_len(instr):
-    """
-    Return string length if all operand bytes are ascii or utf16-le printable
-
-    Works on a capstone instruction
-    """
-    # should have exactly two operands for mov immediate
-    if len(instr.operands) != 2:
-        return 0
-
-    op_value = instr.operands[1].value.imm
-
-    if instr.imm_size == 1:
-        chars = struct.pack("<B", op_value & 0xFF)
-    elif instr.imm_size == 2:
-        chars = struct.pack("<H", op_value & 0xFFFF)
-    elif instr.imm_size == 4:
-        chars = struct.pack("<I", op_value & 0xFFFFFFFF)
-    elif instr.imm_size == 8:
-        chars = struct.pack("<Q", op_value & 0xFFFFFFFFFFFFFFFF)
-    else:
-        raise ValueError("Unhandled operand data type 0x%x." % instr.imm_size)
-
-    if is_printable_ascii(chars):
-        return instr.imm_size
-    if is_printable_utf16le(chars):
-        return instr.imm_size // 2
-
-    return 0
-
-
-def extract_features(f: FunctionHandle, bb: BBHandle) -> Iterator[Tuple[Feature, Address]]:
-    """
-    extract features from the given basic block.
-
-    args:
-      f: the function from which to extract features
-      bb: the basic block to process.
-
-    yields:
-      Tuple[Feature, Address]: the features and their location found in this basic block.
-    """
-    yield BasicBlock(), bb.address
-    for bb_handler in BASIC_BLOCK_HANDLERS:
-        for feature, addr in bb_handler(f, bb):
-            yield feature, addr
-
-
-BASIC_BLOCK_HANDLERS = (
-    extract_bb_tight_loop,
-    extract_stackstring,
-)

capa/features/extractors/smda/extractor.py

@@ -1,57 +0,0 @@
-from typing import List, Tuple
-
-from smda.common.SmdaReport import SmdaReport
-
-import capa.features.extractors.common
-import capa.features.extractors.smda.file
-import capa.features.extractors.smda.insn
-import capa.features.extractors.smda.global_
-import capa.features.extractors.smda.function
-import capa.features.extractors.smda.basicblock
-from capa.features.common import Feature
-from capa.features.address import Address, AbsoluteVirtualAddress
-from capa.features.extractors.base_extractor import BBHandle, InsnHandle, FunctionHandle, FeatureExtractor
-
-
-class SmdaFeatureExtractor(FeatureExtractor):
-    def __init__(self, smda_report: SmdaReport, path):
-        super(SmdaFeatureExtractor, self).__init__()
-        self.smda_report = smda_report
-        self.path = path
-        with open(self.path, "rb") as f:
-            self.buf = f.read()
-
-        # pre-compute these because we'll yield them at *every* scope.
-        self.global_features: List[Tuple[Feature, Address]] = []
-        self.global_features.extend(capa.features.extractors.common.extract_os(self.buf))
-        self.global_features.extend(capa.features.extractors.smda.global_.extract_arch(self.smda_report))
-
-    def get_base_address(self):
-        return AbsoluteVirtualAddress(self.smda_report.base_addr)
-
-    def extract_global_features(self):
-        yield from self.global_features
-
-    def extract_file_features(self):
-        yield from capa.features.extractors.smda.file.extract_features(self.smda_report, self.buf)
-
-    def get_functions(self):
-        for function in self.smda_report.getFunctions():
-            yield FunctionHandle(address=AbsoluteVirtualAddress(function.offset), inner=function)
-
-    def extract_function_features(self, fh):
-        yield from capa.features.extractors.smda.function.extract_features(fh)
-
-    def get_basic_blocks(self, fh):
-        for bb in fh.inner.getBlocks():
-            yield BBHandle(address=AbsoluteVirtualAddress(bb.offset), inner=bb)
-
-    def extract_basic_block_features(self, fh, bbh):
-        yield from capa.features.extractors.smda.basicblock.extract_features(fh, bbh)
-
-    def get_instructions(self, fh, bbh):
-        for smda_ins in bbh.inner.getInstructions():
-            yield InsnHandle(address=AbsoluteVirtualAddress(smda_ins.offset), inner=smda_ins)
-
-    def extract_insn_features(self, fh, bbh, ih):
-        yield from capa.features.extractors.smda.insn.extract_features(fh, bbh, ih)

capa/features/extractors/smda/file.py

@@ -1,103 +0,0 @@
-# if we have SMDA we definitely have lief
-import lief
-
-import capa.features.extractors.common
-import capa.features.extractors.helpers
-import capa.features.extractors.strings
-from capa.features.file import Export, Import, Section
-from capa.features.common import String, Characteristic
-from capa.features.address import FileOffsetAddress, AbsoluteVirtualAddress
-
-
-def extract_file_embedded_pe(buf, **kwargs):
-    for offset, _ in capa.features.extractors.helpers.carve_pe(buf, 1):
-        yield Characteristic("embedded pe"), FileOffsetAddress(offset)
-
-
-def extract_file_export_names(buf, **kwargs):
-    lief_binary = lief.parse(buf)
-
-    if lief_binary is not None:
-        for function in lief_binary.exported_functions:
-            yield Export(function.name), AbsoluteVirtualAddress(function.address)
-
-
-def extract_file_import_names(smda_report, buf):
-    # extract import table info via LIEF
-    lief_binary = lief.parse(buf)
-    if not isinstance(lief_binary, lief.PE.Binary):
-        return
-    for imported_library in lief_binary.imports:
-        library_name = imported_library.name.lower()
-        library_name = library_name[:-4] if library_name.endswith(".dll") else library_name
-        for func in imported_library.entries:
-            va = func.iat_address + smda_report.base_addr
-            if func.name:
-                for name in capa.features.extractors.helpers.generate_symbols(library_name, func.name):
-                    yield Import(name), AbsoluteVirtualAddress(va)
-            elif func.is_ordinal:
-                for name in capa.features.extractors.helpers.generate_symbols(library_name, "#%s" % func.ordinal):
-                    yield Import(name), AbsoluteVirtualAddress(va)
-
-
-def extract_file_section_names(buf, **kwargs):
-    lief_binary = lief.parse(buf)
-    if not isinstance(lief_binary, lief.PE.Binary):
-        return
-    if lief_binary and lief_binary.sections:
-        base_address = lief_binary.optional_header.imagebase
-        for section in lief_binary.sections:
-            yield Section(section.name), AbsoluteVirtualAddress(base_address + section.virtual_address)
-
-
-def extract_file_strings(buf, **kwargs):
-    """
-    extract ASCII and UTF-16 LE strings from file
-    """
-    for s in capa.features.extractors.strings.extract_ascii_strings(buf):
-        yield String(s.s), FileOffsetAddress(s.offset)
-
-    for s in capa.features.extractors.strings.extract_unicode_strings(buf):
-        yield String(s.s), FileOffsetAddress(s.offset)
-
-
-def extract_file_function_names(smda_report, **kwargs):
-    """
-    extract the names of statically-linked library functions.
-    """
-    if False:
-        # using a `yield` here to force this to be a generator, not function.
-        yield NotImplementedError("SMDA doesn't have library matching")
-    return
-
-
-def extract_file_format(buf, **kwargs):
-    yield from capa.features.extractors.common.extract_format(buf)
-
-
-def extract_features(smda_report, buf):
-    """
-    extract file features from given workspace
-
-    args:
-      smda_report (smda.common.SmdaReport): a SmdaReport
-      buf: the raw bytes of the sample
-
-    yields:
-      Tuple[Feature, VA]: a feature and its location.
-    """
-
-    for file_handler in FILE_HANDLERS:
-        for feature, addr in file_handler(smda_report=smda_report, buf=buf):
-            yield feature, addr
-
-
-FILE_HANDLERS = (
-    extract_file_embedded_pe,
-    extract_file_export_names,
-    extract_file_import_names,
-    extract_file_section_names,
-    extract_file_strings,
-    extract_file_function_names,
-    extract_file_format,
-)

capa/features/extractors/smda/function.py

@@ -1,42 +0,0 @@
-from typing import Tuple, Iterator
-
-from capa.features.common import Feature, Characteristic
-from capa.features.address import Address, AbsoluteVirtualAddress
-from capa.features.extractors import loops
-from capa.features.extractors.base_extractor import FunctionHandle
-
-
-def extract_function_calls_to(f: FunctionHandle) -> Iterator[Tuple[Feature, Address]]:
-    for inref in f.inner.inrefs:
-        yield Characteristic("calls to"), AbsoluteVirtualAddress(inref)
-
-
-def extract_function_loop(f: FunctionHandle) -> Iterator[Tuple[Feature, Address]]:
-    """
-    parse if a function has a loop
-    """
-    edges = []
-    for bb_from, bb_tos in f.inner.blockrefs.items():
-        for bb_to in bb_tos:
-            edges.append((bb_from, bb_to))
-
-    if edges and loops.has_loop(edges):
-        yield Characteristic("loop"), f.address
-
-
-def extract_features(f: FunctionHandle):
-    """
-    extract features from the given function.
-
-    args:
-      f: the function from which to extract features
-
-    yields:
-      Tuple[Feature, Address]: the features and their location found in this function.
-    """
-    for func_handler in FUNCTION_HANDLERS:
-        for feature, addr in func_handler(f):
-            yield feature, addr
-
-
-FUNCTION_HANDLERS = (extract_function_calls_to, extract_function_loop)

capa/features/extractors/smda/global_.py

@@ -1,21 +0,0 @@
-import logging
-
-from capa.features.common import ARCH_I386, ARCH_AMD64, Arch
-from capa.features.address import NO_ADDRESS
-
-logger = logging.getLogger(__name__)
-
-
-def extract_arch(smda_report):
-    if smda_report.architecture == "intel":
-        if smda_report.bitness == 32:
-            yield Arch(ARCH_I386), NO_ADDRESS
-        elif smda_report.bitness == 64:
-            yield Arch(ARCH_AMD64), NO_ADDRESS
-    else:
-        # we likely end up here:
-        #  1. handling a new architecture (e.g. aarch64)
-        #
-        # for (1), this logic will need to be updated as the format is implemented.
-        logger.debug("unsupported architecture: %s", smda_report.architecture)
-        return

capa/features/extractors/smda/insn.py

@@ -1,455 +0,0 @@
-import re
-import string
-import struct
-from typing import Tuple, Iterator
-
-import smda
-
-import capa.features.extractors.helpers
-from capa.features.insn import API, MAX_STRUCTURE_SIZE, Number, Offset, Mnemonic, OperandNumber, OperandOffset
-from capa.features.common import MAX_BYTES_FEATURE_SIZE, THUNK_CHAIN_DEPTH_DELTA, Bytes, String, Feature, Characteristic
-from capa.features.address import Address, AbsoluteVirtualAddress
-from capa.features.extractors.base_extractor import BBHandle, InsnHandle, FunctionHandle
-
-# security cookie checks may perform non-zeroing XORs, these are expected within a certain
-# byte range within the first and returning basic blocks, this helps to reduce FP features
-SECURITY_COOKIE_BYTES_DELTA = 0x40
-PATTERN_HEXNUM = re.compile(r"[+\-] (?P<num>0x[a-fA-F0-9]+)")
-PATTERN_SINGLENUM = re.compile(r"[+\-] (?P<num>[0-9])")
-
-
-def extract_insn_api_features(fh: FunctionHandle, bb, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
-    """parse API features from the given instruction."""
-    f: smda.Function = fh.inner
-    insn: smda.Insn = ih.inner
-
-    if ih.address in f.apirefs:
-        api_entry = f.apirefs[ih.address]
-        # reformat
-        dll_name, api_name = api_entry.split("!")
-        dll_name = dll_name.split(".")[0]
-        dll_name = dll_name.lower()
-        for name in capa.features.extractors.helpers.generate_symbols(dll_name, api_name):
-            yield API(name), ih.address
-    elif ih.address in f.outrefs:
-        current_function = f
-        current_instruction = insn
-        for index in range(THUNK_CHAIN_DEPTH_DELTA):
-            if current_function and len(current_function.outrefs[current_instruction.offset]) == 1:
-                target = current_function.outrefs[current_instruction.offset][0]
-                referenced_function = current_function.smda_report.getFunction(target)
-                if referenced_function:
-                    # TODO SMDA: implement this function for both jmp and call, checking if function has 1 instruction which refs an API
-                    if referenced_function.isApiThunk():
-                        api_entry = (
-                            referenced_function.apirefs[target] if target in referenced_function.apirefs else None
-                        )
-                        if api_entry:
-                            # reformat
-                            dll_name, api_name = api_entry.split("!")
-                            dll_name = dll_name.split(".")[0]
-                            dll_name = dll_name.lower()
-                            for name in capa.features.extractors.helpers.generate_symbols(dll_name, api_name):
-                                yield API(name), ih.address
-                    elif referenced_function.num_instructions == 1 and referenced_function.num_outrefs == 1:
-                        current_function = referenced_function
-                        current_instruction = [i for i in referenced_function.getInstructions()][0]
-                else:
-                    return
-
-
-def extract_insn_number_features(fh: FunctionHandle, bb, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
-    """parse number features from the given instruction."""
-    # example:
-    #
-    #     push    3136B0h         ; dwControlCode
-    f: smda.Function = fh.inner
-    insn: smda.Insn = ih.inner
-
-    operands = [o.strip() for o in insn.operands.split(",")]
-    if insn.mnemonic == "add" and operands[0] in ["esp", "rsp"]:
-        # skip things like:
-        #
-        #    .text:00401140                 call    sub_407E2B
-        #    .text:00401145                 add     esp, 0Ch
-        return
-    for i, operand in enumerate(operands):
-        try:
-            # The result of bitwise operations is calculated as though carried out
-            # in two’s complement with an infinite number of sign bits
-            value = int(operand, 16) & ((1 << f.smda_report.bitness) - 1)
-        except ValueError:
-            continue
-        else:
-            yield Number(value), ih.address
-            yield OperandNumber(i, value), ih.address
-
-            if insn.mnemonic == "add" and 0 < value < MAX_STRUCTURE_SIZE:
-                # for pattern like:
-                #
-                #     add eax, 0x10
-                #
-                # assume 0x10 is also an offset (imagine eax is a pointer).
-                yield Offset(value), ih.address
-                yield OperandOffset(i, value), ih.address
-
-
-def read_bytes(smda_report, va, num_bytes=None):
-    """
-    read up to MAX_BYTES_FEATURE_SIZE from the given address.
-    """
-
-    rva = va - smda_report.base_addr
-    if smda_report.buffer is None:
-        raise ValueError("buffer is empty")
-    buffer_end = len(smda_report.buffer)
-    max_bytes = num_bytes if num_bytes is not None else MAX_BYTES_FEATURE_SIZE
-    if rva + max_bytes > buffer_end:
-        return smda_report.buffer[rva:]
-    else:
-        return smda_report.buffer[rva : rva + max_bytes]
-
-
-def derefs(smda_report, p):
-    """
-    recursively follow the given pointer, yielding the valid memory addresses along the way.
-    useful when you may have a pointer to string, or pointer to pointer to string, etc.
-
-    this is a "do what i mean" type of helper function.
-
-    based on the implementation in viv/insn.py
-    """
-    depth = 0
-    while True:
-        if not smda_report.isAddrWithinMemoryImage(p):
-            return
-        yield p
-
-        bytes_ = read_bytes(smda_report, p, num_bytes=4)
-        val = struct.unpack("I", bytes_)[0]
-
-        # sanity: pointer points to self
-        if val == p:
-            return
-
-        # sanity: avoid chains of pointers that are unreasonably deep
-        depth += 1
-        if depth > 10:
-            return
-
-        p = val
-
-
-def extract_insn_bytes_features(fh: FunctionHandle, bb, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
-    """
-    parse byte sequence features from the given instruction.
-    example:
-        #     push    offset iid_004118d4_IShellLinkA ; riid
-    """
-    f: smda.Function = fh.inner
-    insn: smda.Insn = ih.inner
-
-    for data_ref in insn.getDataRefs():
-        for v in derefs(f.smda_report, data_ref):
-            bytes_read = read_bytes(f.smda_report, v)
-            if bytes_read is None:
-                continue
-            if capa.features.extractors.helpers.all_zeros(bytes_read):
-                continue
-
-            yield Bytes(bytes_read), ih.address
-
-
-def detect_ascii_len(smda_report, offset):
-    if smda_report.buffer is None:
-        return 0
-    ascii_len = 0
-    rva = offset - smda_report.base_addr
-    char = smda_report.buffer[rva]
-    while char < 127 and chr(char) in string.printable:
-        ascii_len += 1
-        rva += 1
-        char = smda_report.buffer[rva]
-    if char == 0:
-        return ascii_len
-    return 0
-
-
-def detect_unicode_len(smda_report, offset):
-    if smda_report.buffer is None:
-        return 0
-    unicode_len = 0
-    rva = offset - smda_report.base_addr
-    char = smda_report.buffer[rva]
-    second_char = smda_report.buffer[rva + 1]
-    while char < 127 and chr(char) in string.printable and second_char == 0:
-        unicode_len += 2
-        rva += 2
-        char = smda_report.buffer[rva]
-        second_char = smda_report.buffer[rva + 1]
-    if char == 0 and second_char == 0:
-        return unicode_len
-    return 0
-
-
-def read_string(smda_report, offset):
-    alen = detect_ascii_len(smda_report, offset)
-    if alen > 1:
-        return read_bytes(smda_report, offset, alen).decode("utf-8")
-    ulen = detect_unicode_len(smda_report, offset)
-    if ulen > 2:
-        return read_bytes(smda_report, offset, ulen).decode("utf-16")
-
-
-def extract_insn_string_features(fh: FunctionHandle, bb, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
-    """parse string features from the given instruction."""
-    # example:
-    #
-    #     push    offset aAcr     ; "ACR  > "
-    f: smda.Function = fh.inner
-    insn: smda.Insn = ih.inner
-
-    for data_ref in insn.getDataRefs():
-        for v in derefs(f.smda_report, data_ref):
-            string_read = read_string(f.smda_report, v)
-            if string_read:
-                yield String(string_read.rstrip("\x00")), ih.address
-
-
-def extract_insn_offset_features(f, bb, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
-    """parse structure offset features from the given instruction."""
-    # examples:
-    #
-    #     mov eax, [esi + 4]
-    #     mov eax, [esi + ecx + 16384]
-    insn: smda.Insn = ih.inner
-
-    operands = [o.strip() for o in insn.operands.split(",")]
-    for i, operand in enumerate(operands):
-        if "esp" in operand or "ebp" in operand or "rbp" in operand:
-            continue
-
-        number = 0
-        number_hex = re.search(PATTERN_HEXNUM, operand)
-        number_int = re.search(PATTERN_SINGLENUM, operand)
-        if number_hex:
-            number = int(number_hex.group("num"), 16)
-            number = -1 * number if number_hex.group().startswith("-") else number
-        elif number_int:
-            number = int(number_int.group("num"))
-            number = -1 * number if number_int.group().startswith("-") else number
-
-        if "ptr" not in operand:
-            if (
-                insn.mnemonic == "lea"
-                and i == 1
-                and (operand.count("+") + operand.count("-")) == 1
-                and operand.count("*") == 0
-            ):
-                # for pattern like:
-                #
-                #     lea eax, [ebx + 1]
-                #
-                # assume 1 is also an offset (imagine ebx is a zero register).
-                yield Number(number), ih.address
-                yield OperandNumber(i, number), ih.address
-
-            continue
-
-        yield Offset(number), ih.address
-        yield OperandOffset(i, number), ih.address
-
-
-def is_security_cookie(f, bb, insn):
-    """
-    check if an instruction is related to security cookie checks
-    """
-    # security cookie check should use SP or BP
-    operands = [o.strip() for o in insn.operands.split(",")]
-    if operands[1] not in ["esp", "ebp", "rsp", "rbp"]:
-        return False
-    for index, block in enumerate(f.getBlocks()):
-        # expect security cookie init in first basic block within first bytes (instructions)
-        block_instructions = [i for i in block.getInstructions()]
-        if index == 0 and insn.offset < (block_instructions[0].offset + SECURITY_COOKIE_BYTES_DELTA):
-            return True
-        # ... or within last bytes (instructions) before a return
-        if block_instructions[-1].mnemonic.startswith("ret") and insn.offset > (
-            block_instructions[-1].offset - SECURITY_COOKIE_BYTES_DELTA
-        ):
-            return True
-    return False
-
-
-def extract_insn_nzxor_characteristic_features(
-    fh: FunctionHandle, bh: BBHandle, ih: InsnHandle
-) -> Iterator[Tuple[Feature, Address]]:
-    """
-    parse non-zeroing XOR instruction from the given instruction.
-    ignore expected non-zeroing XORs, e.g. security cookies.
-    """
-    f: smda.Function = fh.inner
-    bb: smda.BasicBlock = bh.inner
-    insn: smda.Insn = ih.inner
-
-    if insn.mnemonic not in ("xor", "xorpd", "xorps", "pxor"):
-        return
-
-    operands = [o.strip() for o in insn.operands.split(",")]
-    if operands[0] == operands[1]:
-        return
-
-    if is_security_cookie(f, bb, insn):
-        return
-
-    yield Characteristic("nzxor"), ih.address
-
-
-def extract_insn_mnemonic_features(f, bb, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
-    """parse mnemonic features from the given instruction."""
-    yield Mnemonic(ih.inner.mnemonic), ih.address
-
-
-def extract_insn_obfs_call_plus_5_characteristic_features(f, bb, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
-    """
-    parse call $+5 instruction from the given instruction.
-    """
-    insn: smda.Insn = ih.inner
-
-    if insn.mnemonic != "call":
-        return
-
-    if not insn.operands.startswith("0x"):
-        return
-
-    if int(insn.operands, 16) == insn.offset + 5:
-        yield Characteristic("call $+5"), ih.address
-
-
-def extract_insn_peb_access_characteristic_features(f, bb, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
-    """
-    parse peb access from the given function. fs:[0x30] on x86, gs:[0x60] on x64
-    """
-    insn: smda.Insn = ih.inner
-
-    if insn.mnemonic not in ["push", "mov"]:
-        return
-
-    operands = [o.strip() for o in insn.operands.split(",")]
-    for operand in operands:
-        if "fs:" in operand and "0x30" in operand:
-            yield Characteristic("peb access"), ih.address
-        elif "gs:" in operand and "0x60" in operand:
-            yield Characteristic("peb access"), ih.address
-
-
-def extract_insn_segment_access_features(f, bb, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
-    """parse the instruction for access to fs or gs"""
-    insn: smda.Insn = ih.inner
-
-    operands = [o.strip() for o in insn.operands.split(",")]
-    for operand in operands:
-        if "fs:" in operand:
-            yield Characteristic("fs access"), ih.address
-        elif "gs:" in operand:
-            yield Characteristic("gs access"), ih.address
-
-
-def extract_insn_cross_section_cflow(fh: FunctionHandle, bb, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
-    """
-    inspect the instruction for a CALL or JMP that crosses section boundaries.
-    """
-    f: smda.Function = fh.inner
-    insn: smda.Insn = ih.inner
-
-    if insn.mnemonic in ["call", "jmp"]:
-        if ih.address in f.apirefs:
-            return
-
-        smda_report = insn.smda_function.smda_report
-        if ih.address in f.outrefs:
-            for target in f.outrefs[ih.address]:
-                if smda_report.getSection(ih.address) != smda_report.getSection(target):
-                    yield Characteristic("cross section flow"), ih.address
-        elif insn.operands.startswith("0x"):
-            target = int(insn.operands, 16)
-            if smda_report.getSection(ih.address) != smda_report.getSection(target):
-                yield Characteristic("cross section flow"), ih.address
-
-
-# this is a feature that's most relevant at the function scope,
-# however, its most efficient to extract at the instruction scope.
-def extract_function_calls_from(fh: FunctionHandle, bb, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
-    f: smda.Function = fh.inner
-    insn: smda.Insn = ih.inner
-
-    if insn.mnemonic != "call":
-        return
-
-    if ih.address in f.outrefs:
-        for outref in f.outrefs[ih.address]:
-            yield Characteristic("calls from"), AbsoluteVirtualAddress(outref)
-
-            if outref == f.offset:
-                # if we found a jump target and it's the function address
-                # mark as recursive
-                yield Characteristic("recursive call"), AbsoluteVirtualAddress(outref)
-    if ih.address in f.apirefs:
-        yield Characteristic("calls from"), ih.address
-
-
-# this is a feature that's most relevant at the function or basic block scope,
-# however, its most efficient to extract at the instruction scope.
-def extract_function_indirect_call_characteristic_features(f, bb, ih: InsnHandle) -> Iterator[Tuple[Feature, Address]]:
-    """
-    extract indirect function call characteristic (e.g., call eax or call dword ptr [edx+4])
-    does not include calls like => call ds:dword_ABD4974
-    """
-    insn: smda.Insn = ih.inner
-
-    if insn.mnemonic != "call":
-        return
-    if insn.operands.startswith("0x"):
-        return False
-    if "qword ptr" in insn.operands and "rip" in insn.operands:
-        return False
-    if insn.operands.startswith("dword ptr [0x"):
-        return False
-    # call edx
-    # call dword ptr [eax+50h]
-    # call qword ptr [rsp+78h]
-    yield Characteristic("indirect call"), ih.address
-
-
-def extract_features(f, bb, insn):
-    """
-    extract features from the given insn.
-
-    args:
-      f: the function to process.
-      bb: the basic block to process.
-      insn: the instruction to process.
-
-    yields:
-      Tuple[Feature, Address]: the features and their location found in this insn.
-    """
-    for insn_handler in INSTRUCTION_HANDLERS:
-        for feature, addr in insn_handler(f, bb, insn):
-            yield feature, addr
-
-
-INSTRUCTION_HANDLERS = (
-    extract_insn_api_features,
-    extract_insn_number_features,
-    extract_insn_string_features,
-    extract_insn_bytes_features,
-    extract_insn_offset_features,
-    extract_insn_nzxor_characteristic_features,
-    extract_insn_mnemonic_features,
-    extract_insn_obfs_call_plus_5_characteristic_features,
-    extract_insn_peb_access_characteristic_features,
-    extract_insn_cross_section_cflow,
-    extract_insn_segment_access_features,
-    extract_function_calls_from,
-    extract_function_indirect_call_characteristic_features,
-)

capa/features/extractors/viv/basicblock.py

@@ -31,7 +31,7 @@ def interface_extract_basic_block_XXX(f: FunctionHandle, bb: BBHandle) -> Iterat
     yields:
       (Feature, Address): the feature and the address at which its found.
     """
-    ...
+    raise NotImplementedError
 
 
 def _bb_has_tight_loop(f, bb):

capa/features/extractors/viv/extractor.py

@@ -26,7 +26,7 @@ logger = logging.getLogger(__name__)
 
 class VivisectFeatureExtractor(FeatureExtractor):
     def __init__(self, vw, path):
-        super(VivisectFeatureExtractor, self).__init__()
+        super().__init__()
         self.vw = vw
         self.path = path
         with open(self.path, "rb") as f:
@@ -34,6 +34,7 @@ class VivisectFeatureExtractor(FeatureExtractor):
 
         # pre-compute these because we'll yield them at *every* scope.
         self.global_features: List[Tuple[Feature, Address]] = []
+        self.global_features.extend(capa.features.extractors.viv.file.extract_file_format(self.buf))
         self.global_features.extend(capa.features.extractors.common.extract_os(self.buf))
         self.global_features.extend(capa.features.extractors.viv.global_.extract_arch(self.vw))
 

capa/features/extractors/viv/function.py

@@ -27,7 +27,7 @@ def interface_extract_function_XXX(fh: FunctionHandle) -> Iterator[Tuple[Feature
     yields:
       (Feature, Address): the feature and the address at which its found.
     """
-    ...
+    raise NotImplementedError
 
 
 def extract_function_calls_to(fhandle: FunctionHandle) -> Iterator[Tuple[Feature, Address]]:
@@ -47,6 +47,10 @@ def extract_function_loop(fhandle: FunctionHandle) -> Iterator[Tuple[Feature, Ad
     for bb in f.basic_blocks:
         if len(bb.instructions) > 0:
             for bva, bflags in bb.instructions[-1].getBranches():
+                if bva is None:
+                    # vivisect may be unable to recover the call target, e.g. on dynamic calls like `call esi`
+                    # for this bva is None, and we don't want to add it for loop detection, ref: vivisect#574
+                    continue
                 # vivisect does not set branch flags for non-conditional jmp so add explicit check
                 if (
                     bflags & envi.BR_COND

capa/features/extractors/viv/indirect_calls.py

@@ -42,7 +42,7 @@ def get_previous_instructions(vw: VivWorkspace, va: int) -> List[int]:
     ret = []
 
     # find the immediate prior instruction.
-    # ensure that it fallsthrough to this one.
+    # ensure that it falls through to this one.
     loc = vw.getPrevLocation(va, adjacent=True)
     if loc is not None:
         ploc = vw.getPrevLocation(va, adjacent=True)
@@ -59,7 +59,7 @@ def get_previous_instructions(vw: VivWorkspace, va: int) -> List[int]:
     #
     # from vivisect.const:
     # xref: (XR_FROM, XR_TO, XR_RTYPE, XR_RFLAG)
-    for (xfrom, _, _, xflag) in vw.getXrefsTo(va, REF_CODE):
+    for xfrom, _, _, xflag in vw.getXrefsTo(va, REF_CODE):
         if (xflag & FAR_BRANCH_MASK) != 0:
             continue
         ret.append(xfrom)

capa/features/extractors/viv/insn.py

@@ -44,7 +44,7 @@ def interface_extract_instruction_XXX(
     yields:
       (Feature, Address): the feature and the address at which its found.
     """
-    ...
+    raise NotImplementedError
 
 
 def get_imports(vw):
@@ -271,6 +271,10 @@ def extract_insn_bytes_features(fh: FunctionHandle, bb, ih: InsnHandle) -> Itera
             if capa.features.extractors.helpers.all_zeros(buf):
                 continue
 
+            if f.vw.isProbablyString(v):
+                # don't extract byte features for obvious strings
+                continue
+
             yield Bytes(buf), ih.address
 
 
@@ -281,7 +285,12 @@ def read_string(vw, offset: int) -> str:
         pass
     else:
         if alen > 0:
-            return read_memory(vw, offset, alen).decode("utf-8")
+            buf = read_memory(vw, offset, alen)
+            if b"\x00" in buf:
+                # account for bug #1271.
+                # remove when vivisect is fixed.
+                buf = buf.partition(b"\x00")[0]
+            return buf.decode("utf-8")
 
     try:
         ulen = vw.detectUnicode(offset)
@@ -300,7 +309,9 @@ def read_string(vw, offset: int) -> str:
                 # vivisect seems to mis-detect the end unicode strings
                 # off by two, too short
                 ulen += 2
-            return read_memory(vw, offset, ulen).decode("utf-16")
+            # partition to account for bug #1271.
+            # remove when vivisect is fixed.
+            return read_memory(vw, offset, ulen).decode("utf-16").partition("\x00")[0]
 
     raise ValueError("not a string", offset)
 
@@ -493,7 +504,8 @@ def extract_function_calls_from(fh: FunctionHandle, bb, ih: InsnHandle) -> Itera
     if isinstance(insn.opers[0], envi.archs.i386.disasm.i386ImmMemOper):
         oper = insn.opers[0]
         target = oper.getOperAddr(insn)
-        yield Characteristic("calls from"), AbsoluteVirtualAddress(target)
+        if target >= 0:
+            yield Characteristic("calls from"), AbsoluteVirtualAddress(target)
 
     # call via thunk on x86,
     # see 9324d1a8ae37a36ae560c37448c9705a at 0x407985
@@ -509,7 +521,8 @@ def extract_function_calls_from(fh: FunctionHandle, bb, ih: InsnHandle) -> Itera
     elif isinstance(insn.opers[0], envi.archs.amd64.disasm.Amd64RipRelOper):
         op = insn.opers[0]
         target = op.getOperAddr(insn)
-        yield Characteristic("calls from"), AbsoluteVirtualAddress(target)
+        if target >= 0:
+            yield Characteristic("calls from"), AbsoluteVirtualAddress(target)
 
     if target and target == f.va:
         # if we found a jump target and it's the function address
@@ -663,11 +676,12 @@ def extract_op_string_features(
 
     for v in derefs(f.vw, v):
         try:
-            s = read_string(f.vw, v)
+            s = read_string(f.vw, v).rstrip("\x00")
         except ValueError:
             continue
         else:
-            yield String(s.rstrip("\x00")), ih.address
+            if len(s) >= 4:
+                yield String(s), ih.address
 
 
 def extract_operand_features(f: FunctionHandle, bb, insn: InsnHandle) -> Iterator[Tuple[Feature, Address]]:

capa/features/file.py

@@ -12,19 +12,19 @@ from capa.features.common import Feature
 class Export(Feature):
     def __init__(self, value: str, description=None):
         # value is export name
-        super(Export, self).__init__(value, description=description)
+        super().__init__(value, description=description)
 
 
 class Import(Feature):
     def __init__(self, value: str, description=None):
         # value is import name
-        super(Import, self).__init__(value, description=description)
+        super().__init__(value, description=description)
 
 
 class Section(Feature):
     def __init__(self, value: str, description=None):
         # value is section name
-        super(Section, self).__init__(value, description=description)
+        super().__init__(value, description=description)
 
 
 class FunctionName(Feature):
@@ -32,7 +32,7 @@ class FunctionName(Feature):
 
     def __init__(self, name: str, description=None):
         # value is function name
-        super(FunctionName, self).__init__(name, description=description)
+        super().__init__(name, description=description)
         # override the name property set by `capa.features.Feature`
         # that would be `functionname` (note missing dash)
         self.name = "function-name"

capa/features/freeze/__init__.py

@@ -12,9 +12,8 @@ See the License for the specific language governing permissions and limitations
 import zlib
 import logging
 from enum import Enum
-from typing import Any, List, Tuple
+from typing import Any, List, Tuple, Union
 
-import dncil.clr.token
 from pydantic import Field, BaseModel
 
 import capa.helpers
@@ -47,7 +46,7 @@ class AddressType(str, Enum):
 
 class Address(HashableModel):
     type: AddressType
-    value: Any
+    value: Union[int, Tuple[int, int], None]
 
     @classmethod
     def from_capa(cls, a: capa.features.address.Address) -> "Address":
@@ -61,10 +60,10 @@ class Address(HashableModel):
             return cls(type=AddressType.FILE, value=int(a))
 
         elif isinstance(a, capa.features.address.DNTokenAddress):
-            return cls(type=AddressType.DN_TOKEN, value=a.token.value)
+            return cls(type=AddressType.DN_TOKEN, value=int(a))
 
         elif isinstance(a, capa.features.address.DNTokenOffsetAddress):
-            return cls(type=AddressType.DN_TOKEN_OFFSET, value=(a.token.value, a.offset))
+            return cls(type=AddressType.DN_TOKEN_OFFSET, value=(a.token, a.offset))
 
         elif a == capa.features.address.NO_ADDRESS or isinstance(a, capa.features.address._NoAddress):
             return cls(type=AddressType.NO_ADDRESS, value=None)
@@ -80,20 +79,27 @@ class Address(HashableModel):
 
     def to_capa(self) -> capa.features.address.Address:
         if self.type is AddressType.ABSOLUTE:
+            assert isinstance(self.value, int)
             return capa.features.address.AbsoluteVirtualAddress(self.value)
 
         elif self.type is AddressType.RELATIVE:
+            assert isinstance(self.value, int)
             return capa.features.address.RelativeVirtualAddress(self.value)
 
         elif self.type is AddressType.FILE:
+            assert isinstance(self.value, int)
             return capa.features.address.FileOffsetAddress(self.value)
 
         elif self.type is AddressType.DN_TOKEN:
-            return capa.features.address.DNTokenAddress(dncil.clr.token.Token(self.value))
+            assert isinstance(self.value, int)
+            return capa.features.address.DNTokenAddress(self.value)
 
         elif self.type is AddressType.DN_TOKEN_OFFSET:
+            assert isinstance(self.value, tuple)
             token, offset = self.value
-            return capa.features.address.DNTokenOffsetAddress(dncil.clr.token.Token(token), offset)
+            assert isinstance(token, int)
+            assert isinstance(offset, int)
+            return capa.features.address.DNTokenOffsetAddress(token, offset)
 
         elif self.type is AddressType.NO_ADDRESS:
             return capa.features.address.NO_ADDRESS
@@ -109,7 +115,11 @@ class Address(HashableModel):
             return True
 
         else:
-            return self.value < other.value
+            assert self.type == other.type
+            # mypy doesn't realize we've proven that either
+            # both are ints, or both are tuples of ints.
+            # and both of these are comparable.
+            return self.value < other.value  # type: ignore
 
 
 class GlobalFeature(HashableModel):
@@ -146,10 +156,13 @@ class BasicBlockFeature(HashableModel):
     versus right at its starting address.
     """
 
-    basic_block: Address
+    basic_block: Address = Field(alias="basic block")
     address: Address
     feature: Feature
 
+    class Config:
+        allow_population_by_field_name = True
+
 
 class InstructionFeature(HashableModel):
     """
@@ -180,7 +193,7 @@ class BasicBlockFeatures(BaseModel):
 class FunctionFeatures(BaseModel):
     address: Address
     features: Tuple[FunctionFeature, ...]
-    basic_blocks: Tuple[BasicBlockFeatures, ...] = Field(alias="basic block")
+    basic_blocks: Tuple[BasicBlockFeatures, ...] = Field(alias="basic blocks")
 
     class Config:
         allow_population_by_field_name = True

capa/features/freeze/features.py

@@ -66,6 +66,9 @@ class FeatureModel(BaseModel):
         elif isinstance(self, APIFeature):
             return capa.features.insn.API(self.api, description=self.description)
 
+        elif isinstance(self, PropertyFeature):
+            return capa.features.insn.Property(self.property, access=self.access, description=self.description)
+
         elif isinstance(self, NumberFeature):
             return capa.features.insn.Number(self.number, description=self.description)
 
@@ -147,6 +150,9 @@ def feature_from_capa(f: capa.features.common.Feature) -> "Feature":
     elif isinstance(f, capa.features.insn.API):
         return APIFeature(api=f.value, description=f.description)
 
+    elif isinstance(f, capa.features.insn.Property):
+        return PropertyFeature(property=f.value, access=f.access, description=f.description)
+
     elif isinstance(f, capa.features.insn.Number):
         return NumberFeature(number=f.value, description=f.description)
 
@@ -266,6 +272,13 @@ class APIFeature(FeatureModel):
     description: Optional[str]
 
 
+class PropertyFeature(FeatureModel):
+    type: str = "property"
+    access: Optional[str]
+    property: str
+    description: Optional[str]
+
+
 class NumberFeature(FeatureModel):
     type: str = "number"
     number: Union[int, float]
@@ -320,13 +333,13 @@ Feature = Union[
     ClassFeature,
     NamespaceFeature,
     APIFeature,
+    PropertyFeature,
     NumberFeature,
     BytesFeature,
     OffsetFeature,
     MnemonicFeature,
     OperandNumberFeature,
     OperandOffsetFeature,
-    # this has to go last because...? pydantic fails to serialize correctly otherwise.
-    # possibly because this feature has no associated value?
+    # Note! this must be last, see #1161
     BasicBlockFeature,
 ]

capa/features/insn.py

@@ -6,9 +6,10 @@
 #  is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and limitations under the License.
 import abc
-from typing import Union
+from typing import Union, Optional
 
-from capa.features.common import Feature
+import capa.helpers
+from capa.features.common import VALID_FEATURE_ACCESS, Feature
 
 
 def hex(n: int) -> str:
@@ -21,16 +22,42 @@ def hex(n: int) -> str:
 
 class API(Feature):
     def __init__(self, name: str, description=None):
-        super(API, self).__init__(name, description=description)
+        super().__init__(name, description=description)
+
+
+class _AccessFeature(Feature, abc.ABC):
+    # superclass: don't use directly
+    def __init__(self, value: str, access: Optional[str] = None, description: Optional[str] = None):
+        super().__init__(value, description=description)
+        if access is not None:
+            if access not in VALID_FEATURE_ACCESS:
+                raise ValueError("%s access type %s not valid" % (self.name, access))
+        self.access = access
+
+    def __hash__(self):
+        return hash((self.name, self.value, self.access))
+
+    def __eq__(self, other):
+        return super().__eq__(other) and self.access == other.access
+
+    def get_name_str(self) -> str:
+        if self.access is not None:
+            return f"{self.name}/{self.access}"
+        return self.name
+
+
+class Property(_AccessFeature):
+    def __init__(self, value: str, access: Optional[str] = None, description=None):
+        super().__init__(value, access=access, description=description)
 
 
 class Number(Feature):
     def __init__(self, value: Union[int, float], description=None):
-        super(Number, self).__init__(value, description=description)
+        super().__init__(value, description=description)
 
     def get_value_str(self):
         if isinstance(self.value, int):
-            return hex(self.value)
+            return capa.helpers.hex(self.value)
         elif isinstance(self.value, float):
             return str(self.value)
         else:
@@ -43,18 +70,19 @@ MAX_STRUCTURE_SIZE = 0x10000
 
 class Offset(Feature):
     def __init__(self, value: int, description=None):
-        super(Offset, self).__init__(value, description=description)
+        super().__init__(value, description=description)
 
     def get_value_str(self):
+        assert isinstance(self.value, int)
         return hex(self.value)
 
 
 class Mnemonic(Feature):
     def __init__(self, value: str, description=None):
-        super(Mnemonic, self).__init__(value, description=description)
+        super().__init__(value, description=description)
 
 
-# max number of operands to consider for a given instrucion.
+# max number of operands to consider for a given instruction.
 # since we only support Intel and .NET, we can assume this is 3
 # which covers cases up to e.g. "vinserti128 ymm0,ymm0,ymm5,1"
 MAX_OPERAND_COUNT = 4
@@ -65,7 +93,7 @@ class _Operand(Feature, abc.ABC):
     # superclass: don't use directly
     # subclasses should set self.name and provide the value string formatter
     def __init__(self, index: int, value: int, description=None):
-        super(_Operand, self).__init__(value, description=description)
+        super().__init__(value, description=description)
         self.index = index
 
     def __hash__(self):
@@ -81,7 +109,7 @@ class OperandNumber(_Operand):
 
     # operand[i].number: 0x12
     def __init__(self, index: int, value: int, description=None):
-        super(OperandNumber, self).__init__(index, value, description=description)
+        super().__init__(index, value, description=description)
         self.name = self.NAMES[index]
 
     def get_value_str(self) -> str:
@@ -95,7 +123,7 @@ class OperandOffset(_Operand):
 
     # operand[i].offset: 0x12
     def __init__(self, index: int, value: int, description=None):
-        super(OperandOffset, self).__init__(index, value, description=description)
+        super().__init__(index, value, description=description)
         self.name = self.NAMES[index]
 
     def get_value_str(self) -> str:

capa/helpers.py

@@ -10,7 +10,7 @@ import logging
 from typing import NoReturn
 
 from capa.exceptions import UnsupportedFormatError
-from capa.features.common import FORMAT_SC32, FORMAT_SC64, FORMAT_UNKNOWN
+from capa.features.common import FORMAT_PE, FORMAT_SC32, FORMAT_SC64, FORMAT_DOTNET, FORMAT_UNKNOWN, Format
 
 EXTENSIONS_SHELLCODE_32 = ("sc32", "raw32")
 EXTENSIONS_SHELLCODE_64 = ("sc64", "raw64")
@@ -18,11 +18,13 @@ EXTENSIONS_ELF = "elf_"
 
 logger = logging.getLogger("capa")
 
-_hex = hex
 
-
-def hex(i):
-    return _hex(int(i))
+def hex(n: int) -> str:
+    """render the given number using upper case hex, like: 0x123ABC"""
+    if n < 0:
+        return "-0x%X" % (-n)
+    else:
+        return "0x%X" % n
 
 
 def get_file_taste(sample_path: str) -> bytes:
@@ -66,11 +68,17 @@ def get_auto_format(path: str) -> str:
 def get_format(sample: str) -> str:
     # imported locally to avoid import cycle
     from capa.features.extractors.common import extract_format
+    from capa.features.extractors.dnfile_ import DnfileFeatureExtractor
 
     with open(sample, "rb") as f:
         buf = f.read()
 
     for feature, _ in extract_format(buf):
+        if feature == Format(FORMAT_PE):
+            dnfile_extractor = DnfileFeatureExtractor(sample)
+            if dnfile_extractor.is_dotnet_file():
+                feature = Format(FORMAT_DOTNET)
+
         assert isinstance(feature.value, str)
         return feature.value
 

capa/ida/helpers.py

@@ -5,20 +5,25 @@
 # Unless required by applicable law or agreed to in writing, software distributed under the License
 #  is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and limitations under the License.
-
+import json
 import logging
 import datetime
 import contextlib
+from typing import Optional
 
 import idc
 import idaapi
 import idautils
 import ida_bytes
 import ida_loader
+from netnode import netnode
 
 import capa
 import capa.version
+import capa.render.utils as rutils
 import capa.features.common
+import capa.render.result_document
+from capa.features.address import AbsoluteVirtualAddress
 
 logger = logging.getLogger("capa")
 
@@ -27,12 +32,17 @@ SUPPORTED_FILE_TYPES = (
     idaapi.f_PE,
     idaapi.f_ELF,
     idaapi.f_BIN,
+    idaapi.f_COFF,
     # idaapi.f_MACHO,
 )
 
 # arch type as returned by idainfo.procname
 SUPPORTED_ARCH_TYPES = ("metapc",)
 
+CAPA_NETNODE = f"$ com.mandiant.capa.v{capa.version.__version__}"
+NETNODE_RESULTS = "results"
+NETNODE_RULES_CACHE_ID = "rules-cache-id"
+
 
 def inform_user_ida_ui(message):
     idaapi.info("%s. Please refer to IDA Output window for more information." % message)
@@ -170,7 +180,7 @@ class IDAIO:
     """
 
     def __init__(self):
-        super(IDAIO, self).__init__()
+        super().__init__()
         self.offset = 0
 
     def seek(self, offset, whence=0):
@@ -180,11 +190,63 @@ class IDAIO:
     def read(self, size):
         ea = ida_loader.get_fileregion_ea(self.offset)
         if ea == idc.BADADDR:
-            # best guess, such as if file is mapped at address 0x0.
-            ea = self.offset
+            logger.debug("cannot read 0x%x bytes at 0x%x (ea: BADADDR)", size, self.offset)
+            return b""
 
         logger.debug("reading 0x%x bytes at 0x%x (ea: 0x%x)", size, self.offset, ea)
-        return ida_bytes.get_bytes(ea, size)
+
+        # get_bytes returns None on error, for consistency with read always return bytes
+        return ida_bytes.get_bytes(ea, size) or b""
 
     def close(self):
         return
+
+
+def save_cached_results(resdoc):
+    logger.debug("saving cached capa results to netnode '%s'", CAPA_NETNODE)
+    n = netnode.Netnode(CAPA_NETNODE)
+    n[NETNODE_RESULTS] = resdoc.json()
+
+
+def idb_contains_cached_results() -> bool:
+    try:
+        n = netnode.Netnode(CAPA_NETNODE)
+        return bool(n.get(NETNODE_RESULTS))
+    except netnode.NetnodeCorruptError as e:
+        logger.error("%s", e, exc_info=True)
+        return False
+
+
+def load_and_verify_cached_results() -> Optional[capa.render.result_document.ResultDocument]:
+    """verifies that cached results have valid (mapped) addresses for the current database"""
+    logger.debug("loading cached capa results from netnode '%s'", CAPA_NETNODE)
+
+    n = netnode.Netnode(CAPA_NETNODE)
+    doc = capa.render.result_document.ResultDocument.parse_obj(json.loads(n[NETNODE_RESULTS]))
+
+    for rule in rutils.capability_rules(doc):
+        for location_, _ in rule.matches:
+            location = location_.to_capa()
+            if isinstance(location, AbsoluteVirtualAddress):
+                ea = int(location)
+                if not idaapi.is_mapped(ea):
+                    logger.error("cached address %s is not a valid location in this database", hex(ea))
+                    return None
+    return doc
+
+
+def save_rules_cache_id(ruleset_id):
+    logger.debug("saving ruleset ID to netnode '%s'", CAPA_NETNODE)
+    n = netnode.Netnode(CAPA_NETNODE)
+    n[NETNODE_RULES_CACHE_ID] = ruleset_id
+
+
+def load_rules_cache_id():
+    n = netnode.Netnode(CAPA_NETNODE)
+    return n[NETNODE_RULES_CACHE_ID]
+
+
+def delete_cached_results():
+    logger.debug("deleting cached capa data")
+    n = netnode.Netnode(CAPA_NETNODE)
+    del n[NETNODE_RESULTS]

capa/ida/plugin/README.md

@@ -1,8 +1,8 @@
 ![capa explorer](../../../.github/capa-explorer-logo.png)
 
 capa explorer is an IDAPython plugin that integrates the FLARE team's open-source framework, capa, with IDA Pro. capa is a framework that uses a well-defined collection of rules to 
-identify capabilities in a program. You can run capa against a PE file or shellcode and it tells you what it thinks the program can do. For example, it might suggest that 
-the program is a backdoor, can install services, or relies on HTTP to communicate. capa explorer runs capa directly against your IDA Pro database (IDB) without requiring access
+identify capabilities in a program. You can run capa against a PE file, ELF file, or shellcode and it tells you what it thinks the program can do. For example, it might suggest that 
+the program is a backdoor, can install services, or relies on HTTP to communicate. capa explorer runs capa analysis on your IDA Pro database (IDB) without needing access
 to the original binary file. Once a database has been analyzed, capa explorer helps you identify interesting areas of a program and build new capa rules using features extracted from your IDB.
 
 We love using capa explorer during malware analysis because it teaches us what parts of a program suggest a behavior. As we click on rows, capa explorer jumps directly 
@@ -21,10 +21,10 @@ We can use capa explorer to navigate our Disassembly view directly to the suspec
 Using the `Rule Information` and `Details` columns capa explorer shows us that the suspect function matched `self delete via COMSPEC environment variable` because it contains capa rule matches for `create process`, `get COMSPEC environment variable`,
 and `query environment variable`, references to the strings `COMSPEC`, ` > nul`, and `/c del `, and calls to the Windows API functions `GetEnvironmentVariableA` and `ShellExecuteEx`.
 
-capa explorer also helps you build new capa rules. To start select the `Rule Generator` tab, navigate to a function in your Disassembly view,
+capa explorer also helps you build and test new capa rules. To start, select the `Rule Generator` tab, navigate to a function in your Disassembly view,
 and click `Analyze`. capa explorer will extract features from the function and display them in the `Features` pane. You can add features listed in this pane to the `Editor` pane
 by either double-clicking a feature or using multi-select + right-click to add multiple features at once. The `Preview` and `Editor` panes help edit your rule. Use the `Preview` pane
-to modify the rule text directly and the `Editor` pane to construct and rearrange your hierarchy of statements and features. When you finish a rule you can save it directly to a file by clicking `Save`.
+to modify rule text directly and the `Editor` pane to construct and rearrange your hierarchy of statements and features. When you finish a rule you can save it directly to a file by clicking `Save`.
 
 ![](../../../doc/img/rulegen_expanded.png)
 
@@ -32,62 +32,32 @@ For more information on the FLARE team's open-source framework, capa, check out
 
 ## Getting Started
 
-### Requirements
+### Installation
 
-capa explorer supports Python versions >= 3.7.x and the following IDA Pro versions:
-
-* IDA 7.4
-* IDA 7.5
-* IDA 7.6 (caveat below)
-* IDA 7.7
-
-capa explorer is however limited to the Python versions supported by your IDA installation (which may not include all Python versions >= 3.7.x). Based on our testing the following matrix shows the Python versions supported
-by each supported IDA version:
-
-| | IDA 7.4 | IDA 7.5 | IDA 7.6 |
-| --- | --- | --- | --- |
-| Python 3.7.x | Yes | Yes | Yes |
-| Python 3.8.x | Partial (see below) | Yes | Yes |
-| Python 3.9.x | No | Partial (see below) | Yes |
-
-To use capa explorer with IDA 7.4 and Python 3.8.x you must follow the instructions provided by hex-rays [here](https://hex-rays.com/blog/ida-7-4-and-python-3-8/).
-
-To use capa explorer with IDA 7.5 and Python 3.9.x you must follow the instructions provided by hex-rays [here](https://hex-rays.com/blog/python-3-9-support-for-ida-7-5/).
-
-If you encounter issues with your specific setup, please open a new [Issue](https://github.com/mandiant/capa/issues).
-
-#### IDA 7.6 caveat: IDA 7.6sp1 or patch required
-
-As described [here](https://www.hex-rays.com/blog/ida-7-6-empty-qtreeview-qtreewidget/):
-
-> A rather nasty issue evaded our testing and found its way into IDA 7.6: using the PyQt5 modules that are shipped with IDA, QTreeView (or QTreeWidget) instances will always fail to display contents.
-
-Therefore, in order to use capa under IDA 7.6 you need the [Service Pack 1 for IDA 7.6](https://www.hex-rays.com/products/ida/news/7_6sp1). Alternatively, you can download and install the fix corresponding to your IDA installation, replacing the original QtWidgets DLL with the one contained in the .zip file (links to Hex-Rays):
-
-
-  - Windows: [pyqt5_qtwidgets_win](https://www.hex-rays.com/wp-content/uploads/2021/04/pyqt5_qtwidgets_win.zip)
-  - Linux: [pyqt5_qtwidgets_linux](https://www.hex-rays.com/wp-content/uploads/2021/04/pyqt5_qtwidgets_linux.zip)
-  - MacOS (Intel): [pyqt5_qtwidgets_mac_x64](https://www.hex-rays.com/wp-content/uploads/2021/04/pyqt5_qtwidgets_mac_x64.zip)
-  - MacOS (AppleSilicon): [pyqt5_qtwidgets_mac_arm](https://www.hex-rays.com/wp-content/uploads/2021/04/pyqt5_qtwidgets_mac_arm.zip)
+You can install capa explorer using the following steps:
 
+1. Install capa and its dependencies from PyPI using the Python interpreter configured for your IDA installation:
+    ```
+    $ pip install flare-capa
+    ```
+2. Download and extract the [official capa rules](https://github.com/mandiant/capa-rules/releases) that match the version of capa you have installed
+   1. Use the following command to view the version of capa you have installed:
+   ```commandline
+    $ pip show flare-capa
+    OR
+    $ capa --version
+    ```
+3. Copy [capa_explorer.py](https://raw.githubusercontent.com/mandiant/capa/master/capa/ida/plugin/capa_explorer.py) to your IDA plugins directory
+   - find your plugin directories via `idaapi.get_ida_subdirs("plugins")` or see this [Hex-Rays blog](https://hex-rays.com/blog/igors-tip-of-the-week-103-sharing-plugins-between-ida-installs/)
+   - common paths are `%APPDATA%\Hex-Rays\IDA Pro\plugins` (Windows) or `$HOME/.idapro/plugins` on Linux/Mac
 
 ### Supported File Types
 
 capa explorer is limited to the file types supported by capa, which include:
 
-* Windows x86 (32- and 64-bit) PE and ELF files
+* Windows x86 (32- and 64-bit) PE files
 * Windows x86 (32- and 64-bit) shellcode
-
-### Installation
-
-You can install capa explorer using the following steps:
-
-1. Install capa and its dependencies from PyPI for the Python interpreter used by your IDA installation:
-    ```
-    $ pip install flare-capa
-    ```
-3. Download the [standard collection of capa rules](https://github.com/mandiant/capa-rules) (capa explorer needs capa rules to analyze a database)
-4. Copy [capa_explorer.py](https://raw.githubusercontent.com/mandiant/capa/master/capa/ida/plugin/capa_explorer.py) to your IDA plugins directory
+* ELF files on various operating systems
 
 ### Usage
 
@@ -97,19 +67,20 @@ You can install capa explorer using the following steps:
 3. Select the `Program Analysis` tab
 4. Click the `Analyze` button
 
-When running capa explorer for the first time you are prompted to select a file directory containing capa rules. The plugin conveniently
-remembers your selection for future runs; you can change this selection and other default settings by clicking `Settings`. We recommend 
-downloading and using the [standard collection of capa rules](https://github.com/mandiant/capa-rules) when getting started with the plugin.
+The first time you run capa explorer you will be asked to specify a local directory containing capa rules to use for analysis. We recommend downloading and extracting the [official capa rules](https://github.com/mandiant/capa-rules/releases) that match 
+the version of capa you have installed (see installation instructions above for more details). capa explorer remembers your selection for future analysis which you
+can update using the `Settings` button.
 
 #### Tips for Program Analysis
 
 * Start analysis by clicking the `Analyze` button
+  * capa explorer caches results to the database and reuses them across IDA sessions 
 * Reset the plugin user interface and remove highlighting from your Disassembly view by clicking the `Reset` button
-* Change your capa rules directory and other default settings by clicking `Settings`
+* Change your local capa rules directory, auto analysis settings, and other default settings by clicking the `Settings` button
 * Hover your cursor over a rule match to view the source content of the rule
 * Double-click the `Address` column to navigate your Disassembly view to the address of the associated feature
 * Double-click a result in the `Rule Information` column to expand its children
-* Select a checkbox in the `Rule Information` column to highlight the address of the associated feature in your Dissasembly view
+* Select a checkbox in the `Rule Information` column to highlight the address of the associated feature in your Disassembly view
 
 #### Tips for Rule Generator
 
@@ -122,6 +93,22 @@ downloading and using the [standard collection of capa rules](https://github.com
 * Directly edit rule text and metadata fields using the `Preview` pane
 * Change the default rule author and default rule scope displayed in the `Preview` pane by clicking `Settings`
 
+### Requirements
+
+capa explorer supports Python versions >= 3.7.x and IDA Pro versions >= 7.4. The following IDA Pro versions have been tested:
+
+* IDA 7.4
+* IDA 7.5
+* IDA 7.6 Service Pack 1
+* IDA 7.7
+* IDA 8.0
+* IDA 8.1
+* IDA 8.2
+
+capa explorer is however limited to the Python versions supported by your IDA installation (which may not include all Python versions >= 3.7.x).
+
+If you encounter issues with your specific setup, please open a new [Issue](https://github.com/mandiant/capa/issues).
+
 ## Development
 
 capa explorer is packaged with capa so you will need to install capa locally for development. You can install capa locally by following the steps outlined in `Method 3: Inspecting the capa source code` of the [capa 

capa/ida/plugin/__init__.py

@@ -17,7 +17,6 @@ logger = logging.getLogger(__name__)
 
 
 class CapaExplorerPlugin(idaapi.plugin_t):
-
     # Mandatory definitions
     PLUGIN_NAME = "FLARE capa explorer"
     PLUGIN_VERSION = "1.0.0"
@@ -85,7 +84,7 @@ class CapaExplorerPlugin(idaapi.plugin_t):
 # so we need to register a callback that's invoked from the main thread after the plugin is registered.
 #
 # after a lot of guess-and-check, we can use `UI_Hooks.updated_actions` to
-#  receive notications after IDA has created an action for each plugin.
+#  receive notifications after IDA has created an action for each plugin.
 # so, create this hook, wait for capa plugin to load, set the icon, and unhook.
 
 
@@ -93,7 +92,7 @@ class OnUpdatedActionsHook(ida_kernwin.UI_Hooks):
     """register a callback to be invoked each time the UI actions are updated"""
 
     def __init__(self, cb):
-        super(OnUpdatedActionsHook, self).__init__()
+        super().__init__()
         self.cb = cb
 
     def updated_actions(self):

capa/ida/plugin/cache.py

@@ -0,0 +1,220 @@
+# Copyright (C) 2020 Mandiant, Inc. All Rights Reserved.
+# Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at: [package root]/LICENSE.txt
+# Unless required by applicable law or agreed to in writing, software distributed under the License
+#  is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and limitations under the License.
+
+from __future__ import annotations
+
+import itertools
+import collections
+from typing import Set, Dict, List, Tuple, Union, Optional
+
+import capa.engine
+from capa.rules import Scope, RuleSet
+from capa.engine import FeatureSet, MatchResults
+from capa.features.address import NO_ADDRESS, Address
+from capa.ida.plugin.extractor import CapaExplorerFeatureExtractor
+from capa.features.extractors.base_extractor import BBHandle, InsnHandle, FunctionHandle
+
+
+class CapaRuleGenFeatureCacheNode:
+    def __init__(
+        self,
+        inner: Optional[Union[FunctionHandle, BBHandle, InsnHandle]],
+        parent: Optional[CapaRuleGenFeatureCacheNode],
+    ):
+        self.inner: Optional[Union[FunctionHandle, BBHandle, InsnHandle]] = inner
+        self.address = NO_ADDRESS if self.inner is None else self.inner.address
+        self.parent: Optional[CapaRuleGenFeatureCacheNode] = parent
+
+        if self.parent is not None:
+            self.parent.children.add(self)
+
+        self.features: FeatureSet = collections.defaultdict(set)
+        self.children: Set[CapaRuleGenFeatureCacheNode] = set()
+
+    def __hash__(self):
+        # TODO: unique enough?
+        return hash((self.address,))
+
+    def __eq__(self, other):
+        if not isinstance(other, type(self)):
+            return NotImplemented
+        # TODO: unique enough?
+        return self.address == other.address
+
+
+class CapaRuleGenFeatureCache:
+    def __init__(self, fh_list: List[FunctionHandle], extractor: CapaExplorerFeatureExtractor):
+        self.global_features: FeatureSet = collections.defaultdict(set)
+
+        self.file_node: CapaRuleGenFeatureCacheNode = CapaRuleGenFeatureCacheNode(None, None)
+        self.func_nodes: Dict[Address, CapaRuleGenFeatureCacheNode] = {}
+        self.bb_nodes: Dict[Address, CapaRuleGenFeatureCacheNode] = {}
+        self.insn_nodes: Dict[Address, CapaRuleGenFeatureCacheNode] = {}
+
+        self._find_global_features(extractor)
+        self._find_file_features(extractor)
+        self._find_function_and_below_features(fh_list, extractor)
+
+    def _find_global_features(self, extractor: CapaExplorerFeatureExtractor):
+        for feature, addr in extractor.extract_global_features():
+            # not all global features may have virtual addresses.
+            # if not, then at least ensure the feature shows up in the index.
+            # the set of addresses will still be empty.
+            if addr is not None:
+                self.global_features[feature].add(addr)
+            else:
+                if feature not in self.global_features:
+                    self.global_features[feature] = set()
+
+    def _find_file_features(self, extractor: CapaExplorerFeatureExtractor):
+        # not all file features may have virtual addresses.
+        # if not, then at least ensure the feature shows up in the index.
+        # the set of addresses will still be empty.
+        for feature, addr in extractor.extract_file_features():
+            if addr is not None:
+                self.file_node.features[feature].add(addr)
+            else:
+                if feature not in self.file_node.features:
+                    self.file_node.features[feature] = set()
+
+    def _find_function_and_below_features(self, fh_list: List[FunctionHandle], extractor: CapaExplorerFeatureExtractor):
+        for fh in fh_list:
+            f_node: CapaRuleGenFeatureCacheNode = CapaRuleGenFeatureCacheNode(fh, self.file_node)
+
+            # extract basic block and below features
+            for bbh in extractor.get_basic_blocks(fh):
+                bb_node: CapaRuleGenFeatureCacheNode = CapaRuleGenFeatureCacheNode(bbh, f_node)
+
+                # extract instruction features
+                for ih in extractor.get_instructions(fh, bbh):
+                    inode: CapaRuleGenFeatureCacheNode = CapaRuleGenFeatureCacheNode(ih, bb_node)
+
+                    for feature, addr in extractor.extract_insn_features(fh, bbh, ih):
+                        inode.features[feature].add(addr)
+
+                    self.insn_nodes[inode.address] = inode
+
+                # extract basic block features
+                for feature, addr in extractor.extract_basic_block_features(fh, bbh):
+                    bb_node.features[feature].add(addr)
+
+                # store basic block features in cache and function parent
+                self.bb_nodes[bb_node.address] = bb_node
+
+            # extract function features
+            for feature, addr in extractor.extract_function_features(fh):
+                f_node.features[feature].add(addr)
+
+            self.func_nodes[f_node.address] = f_node
+
+    def _find_instruction_capabilities(
+        self, ruleset: RuleSet, insn: CapaRuleGenFeatureCacheNode
+    ) -> Tuple[FeatureSet, MatchResults]:
+        features: FeatureSet = collections.defaultdict(set)
+
+        for feature, locs in itertools.chain(insn.features.items(), self.global_features.items()):
+            features[feature].update(locs)
+
+        _, matches = ruleset.match(Scope.INSTRUCTION, features, insn.address)
+        for name, result in matches.items():
+            rule = ruleset[name]
+            for addr, _ in result:
+                capa.engine.index_rule_matches(features, rule, [addr])
+
+        return features, matches
+
+    def _find_basic_block_capabilities(
+        self, ruleset: RuleSet, bb: CapaRuleGenFeatureCacheNode
+    ) -> Tuple[FeatureSet, MatchResults, MatchResults]:
+        features: FeatureSet = collections.defaultdict(set)
+        insn_matches: MatchResults = collections.defaultdict(list)
+
+        for insn in bb.children:
+            ifeatures, imatches = self._find_instruction_capabilities(ruleset, insn)
+            for feature, locs in ifeatures.items():
+                features[feature].update(locs)
+            for name, result in imatches.items():
+                insn_matches[name].extend(result)
+
+        for feature, locs in itertools.chain(bb.features.items(), self.global_features.items()):
+            features[feature].update(locs)
+
+        _, matches = ruleset.match(Scope.BASIC_BLOCK, features, bb.address)
+        for name, result in matches.items():
+            rule = ruleset[name]
+            for loc, _ in result:
+                capa.engine.index_rule_matches(features, rule, [loc])
+
+        return features, matches, insn_matches
+
+    def find_code_capabilities(
+        self, ruleset: RuleSet, fh: FunctionHandle
+    ) -> Tuple[FeatureSet, MatchResults, MatchResults, MatchResults]:
+        f_node: Optional[CapaRuleGenFeatureCacheNode] = self.func_nodes.get(fh.address, None)
+        if f_node is None:
+            return {}, {}, {}, {}
+
+        insn_matches: MatchResults = collections.defaultdict(list)
+        bb_matches: MatchResults = collections.defaultdict(list)
+        function_features: FeatureSet = collections.defaultdict(set)
+
+        for bb in f_node.children:
+            features, bmatches, imatches = self._find_basic_block_capabilities(ruleset, bb)
+            for feature, locs in features.items():
+                function_features[feature].update(locs)
+            for name, result in bmatches.items():
+                bb_matches[name].extend(result)
+            for name, result in imatches.items():
+                insn_matches[name].extend(result)
+
+        for feature, locs in itertools.chain(f_node.features.items(), self.global_features.items()):
+            function_features[feature].update(locs)
+
+        _, function_matches = ruleset.match(Scope.FUNCTION, function_features, f_node.address)
+        return function_features, function_matches, bb_matches, insn_matches
+
+    def find_file_capabilities(self, ruleset: RuleSet) -> Tuple[FeatureSet, MatchResults]:
+        features: FeatureSet = collections.defaultdict(set)
+
+        for func_node in self.file_node.children:
+            assert func_node.inner is not None
+            assert isinstance(func_node.inner, FunctionHandle)
+
+            func_features, _, _, _ = self.find_code_capabilities(ruleset, func_node.inner)
+            for feature, locs in func_features.items():
+                features[feature].update(locs)
+
+        for feature, locs in itertools.chain(self.file_node.features.items(), self.global_features.items()):
+            features[feature].update(locs)
+
+        _, matches = ruleset.match(Scope.FILE, features, NO_ADDRESS)
+        return features, matches
+
+    def get_all_function_features(self, fh: FunctionHandle) -> FeatureSet:
+        f_node: Optional[CapaRuleGenFeatureCacheNode] = self.func_nodes.get(fh.address, None)
+        if f_node is None:
+            return {}
+
+        all_function_features: FeatureSet = collections.defaultdict(set)
+        all_function_features.update(f_node.features)
+
+        for bb_node in f_node.children:
+            for i_node in bb_node.children:
+                for feature, locs in i_node.features.items():
+                    all_function_features[feature].update(locs)
+            for feature, locs in bb_node.features.items():
+                all_function_features[feature].update(locs)
+
+        # include global features just once
+        for feature, locs in self.global_features.items():
+            all_function_features[feature].update(locs)
+
+        return all_function_features
+
+    def get_all_file_features(self):
+        yield from itertools.chain(self.file_node.features.items(), self.global_features.items())

capa/ida/plugin/error.py

@@ -0,0 +1,13 @@
+# Copyright (C) 2020 Mandiant, Inc. All Rights Reserved.
+# Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at: [package root]/LICENSE.txt
+# Unless required by applicable law or agreed to in writing, software distributed under the License
+#  is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and limitations under the License.
+
+
+class UserCancelledError(Exception):
+    """throw exception when user cancels action"""
+
+    pass

capa/ida/plugin/extractor.py

@@ -0,0 +1,44 @@
+# Copyright (C) 2020 Mandiant, Inc. All Rights Reserved.
+# Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at: [package root]/LICENSE.txt
+# Unless required by applicable law or agreed to in writing, software distributed under the License
+#  is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and limitations under the License.
+
+import ida_kernwin
+from PyQt5 import QtCore
+
+from capa.ida.plugin.error import UserCancelledError
+from capa.features.extractors.ida.extractor import IdaFeatureExtractor
+from capa.features.extractors.base_extractor import FunctionHandle
+
+
+class CapaExplorerProgressIndicator(QtCore.QObject):
+    """implement progress signal, used during feature extraction"""
+
+    progress = QtCore.pyqtSignal(str)
+
+    def update(self, text):
+        """emit progress update
+
+        check if user cancelled action, raise exception for parent function to catch
+        """
+        if ida_kernwin.user_cancelled():
+            raise UserCancelledError("user cancelled")
+        self.progress.emit("extracting features from %s" % text)
+
+
+class CapaExplorerFeatureExtractor(IdaFeatureExtractor):
+    """subclass the IdaFeatureExtractor
+
+    track progress during feature extraction, also allow user to cancel feature extraction
+    """
+
+    def __init__(self):
+        super().__init__()
+        self.indicator = CapaExplorerProgressIndicator()
+
+    def extract_function_features(self, fh: FunctionHandle):
+        self.indicator.update("function at 0x%X" % fh.inner.start_ea)
+        return super().extract_function_features(fh)

capa/ida/plugin/hooks.py

@@ -16,7 +16,7 @@ class CapaExplorerIdaHooks(idaapi.UI_Hooks):
         @param screen_ea_changed_hook: function hook for IDA screen ea changed
         @param action_hooks: dict of IDA action handles
         """
-        super(CapaExplorerIdaHooks, self).__init__()
+        super().__init__()
 
         self.screen_ea_changed_hook = screen_ea_changed_hook
         self.process_action_hooks = action_hooks

capa/ida/plugin/item.py

@@ -36,7 +36,7 @@ def ea_to_hex(ea):
 class CapaExplorerDataItem:
     """store data for CapaExplorerDataModel"""
 
-    def __init__(self, parent: "CapaExplorerDataItem", data: List[str], can_check=True):
+    def __init__(self, parent: Optional["CapaExplorerDataItem"], data: List[str], can_check=True):
         """initialize item"""
         self.pred = parent
         self._data = data
@@ -110,7 +110,7 @@ class CapaExplorerDataItem:
         except IndexError:
             return None
 
-    def parent(self) -> "CapaExplorerDataItem":
+    def parent(self) -> Optional["CapaExplorerDataItem"]:
         """get parent"""
         return self.pred
 
@@ -181,7 +181,7 @@ class CapaExplorerRuleItem(CapaExplorerDataItem):
         @param source: rule source (tooltip)
         """
         display = self.fmt % (name, count) if count > 1 else name
-        super(CapaExplorerRuleItem, self).__init__(parent, [display, "", namespace], can_check)
+        super().__init__(parent, [display, "", namespace], can_check)
         self._source = source
 
     @property
@@ -200,7 +200,7 @@ class CapaExplorerRuleMatchItem(CapaExplorerDataItem):
         @param display: text to display in UI
         @param source: rule match source to display (tooltip)
         """
-        super(CapaExplorerRuleMatchItem, self).__init__(parent, [display, "", ""])
+        super().__init__(parent, [display, "", ""])
         self._source = source
 
     @property
@@ -222,14 +222,12 @@ class CapaExplorerFunctionItem(CapaExplorerDataItem):
         """
         assert isinstance(location, AbsoluteVirtualAddress)
         ea = int(location)
-        super(CapaExplorerFunctionItem, self).__init__(
-            parent, [self.fmt % idaapi.get_name(ea), ea_to_hex(ea), ""], can_check
-        )
+        super().__init__(parent, [self.fmt % idaapi.get_name(ea), ea_to_hex(ea), ""], can_check)
 
     @property
     def info(self):
         """return function name"""
-        info = super(CapaExplorerFunctionItem, self).info
+        info = super().info
         display = info_to_name(info)
         return display if display else info
 
@@ -255,7 +253,7 @@ class CapaExplorerSubscopeItem(CapaExplorerDataItem):
         @param parent: parent node
         @param scope: subscope name
         """
-        super(CapaExplorerSubscopeItem, self).__init__(parent, [self.fmt % scope, "", ""])
+        super().__init__(parent, [self.fmt % scope, "", ""])
 
 
 class CapaExplorerBlockItem(CapaExplorerDataItem):
@@ -271,7 +269,13 @@ class CapaExplorerBlockItem(CapaExplorerDataItem):
         """
         assert isinstance(location, AbsoluteVirtualAddress)
         ea = int(location)
-        super(CapaExplorerBlockItem, self).__init__(parent, [self.fmt % ea, ea_to_hex(ea), ""])
+        super().__init__(parent, [self.fmt % ea, ea_to_hex(ea), ""])
+
+
+class CapaExplorerInstructionItem(CapaExplorerBlockItem):
+    """store data for instruction match"""
+
+    fmt = "instruction(loc_%08X)"
 
 
 class CapaExplorerDefaultItem(CapaExplorerDataItem):
@@ -292,9 +296,7 @@ class CapaExplorerDefaultItem(CapaExplorerDataItem):
             assert isinstance(location, AbsoluteVirtualAddress)
             ea = int(location)
 
-        super(CapaExplorerDefaultItem, self).__init__(
-            parent, [display, ea_to_hex(ea) if ea is not None else "", details]
-        )
+        super().__init__(parent, [display, ea_to_hex(ea) if ea is not None else "", details])
 
 
 class CapaExplorerFeatureItem(CapaExplorerDataItem):
@@ -313,9 +315,9 @@ class CapaExplorerFeatureItem(CapaExplorerDataItem):
         if location:
             assert isinstance(location, (AbsoluteVirtualAddress, FileOffsetAddress))
             ea = int(location)
-            super(CapaExplorerFeatureItem, self).__init__(parent, [display, ea_to_hex(ea), details])
+            super().__init__(parent, [display, ea_to_hex(ea), details])
         else:
-            super(CapaExplorerFeatureItem, self).__init__(parent, [display, "", details])
+            super().__init__(parent, [display, "", details])
 
 
 class CapaExplorerInstructionViewItem(CapaExplorerFeatureItem):
@@ -333,7 +335,7 @@ class CapaExplorerInstructionViewItem(CapaExplorerFeatureItem):
         assert isinstance(location, AbsoluteVirtualAddress)
         ea = int(location)
         details = capa.ida.helpers.get_disasm_line(ea)
-        super(CapaExplorerInstructionViewItem, self).__init__(parent, display, location=location, details=details)
+        super().__init__(parent, display, location=location, details=details)
         self.ida_highlight = idc.get_color(ea, idc.CIC_ITEM)
 
 
@@ -359,7 +361,7 @@ class CapaExplorerByteViewItem(CapaExplorerFeatureItem):
             byte_snap = codecs.encode(byte_snap, "hex").upper()
             details = " ".join([byte_snap[i : i + 2].decode() for i in range(0, len(byte_snap), 2)])
 
-        super(CapaExplorerByteViewItem, self).__init__(parent, display, location=location, details=details)
+        super().__init__(parent, display, location=location, details=details)
         self.ida_highlight = idc.get_color(ea, idc.CIC_ITEM)
 
 
@@ -376,5 +378,5 @@ class CapaExplorerStringViewItem(CapaExplorerFeatureItem):
         assert isinstance(location, (AbsoluteVirtualAddress, FileOffsetAddress))
         ea = int(location)
 
-        super(CapaExplorerStringViewItem, self).__init__(parent, display, location=location, details=value)
+        super().__init__(parent, display, location=location, details=value)
         self.ida_highlight = idc.get_color(ea, idc.CIC_ITEM)

capa/ida/plugin/model.py

@@ -6,7 +6,7 @@
 #  is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and limitations under the License.
 
-from typing import Set, Dict, List, Tuple
+from typing import Set, Dict, List, Tuple, Optional
 from collections import deque
 
 import idc
@@ -31,6 +31,7 @@ from capa.ida.plugin.item import (
     CapaExplorerSubscopeItem,
     CapaExplorerRuleMatchItem,
     CapaExplorerStringViewItem,
+    CapaExplorerInstructionItem,
     CapaExplorerInstructionViewItem,
 )
 from capa.features.address import Address, AbsoluteVirtualAddress
@@ -50,7 +51,7 @@ class CapaExplorerDataModel(QtCore.QAbstractItemModel):
 
     def __init__(self, parent=None):
         """initialize model"""
-        super(CapaExplorerDataModel, self).__init__(parent)
+        super().__init__(parent)
         # root node does not have parent, contains header columns
         self.root_node = CapaExplorerDataItem(None, ["Rule Information", "Address", "Details"])
 
@@ -142,6 +143,7 @@ class CapaExplorerDataModel(QtCore.QAbstractItemModel):
                     CapaExplorerFunctionItem,
                     CapaExplorerFeatureItem,
                     CapaExplorerSubscopeItem,
+                    CapaExplorerInstructionItem,
                 ),
             )
             and column == CapaExplorerDataModel.COLUMN_INDEX_RULE_INFORMATION
@@ -363,12 +365,13 @@ class CapaExplorerDataModel(QtCore.QAbstractItemModel):
         @param doc: result doc
         """
 
-        if isinstance(statement, (rd.AndStatement, rd.OrStatement, rd.OptionalStatement)):
-            display = statement.type
-            if statement.description:
-                display += " (%s)" % statement.description
-            return CapaExplorerDefaultItem(parent, display)
-        elif isinstance(statement, rd.NotStatement):
+        if isinstance(statement, rd.CompoundStatement):
+            if statement.type != rd.CompoundStatementType.NOT:
+                display = statement.type
+                if statement.description:
+                    display += " (%s)" % statement.description
+                return CapaExplorerDefaultItem(parent, display)
+        elif isinstance(statement, rd.CompoundStatement) and statement.type == rd.CompoundStatementType.NOT:
             # TODO: do we display 'not'
             pass
         elif isinstance(statement, rd.SomeStatement):
@@ -422,7 +425,7 @@ class CapaExplorerDataModel(QtCore.QAbstractItemModel):
             return
 
         # optional statement with no successful children is empty
-        if isinstance(match.node, rd.StatementNode) and isinstance(match.node.statement, rd.OptionalStatement):
+        if isinstance(match.node, rd.StatementNode) and match.node.statement.type == rd.CompoundStatementType.OPTIONAL:
             if not any(map(lambda m: m.success, match.children)):
                 return
 
@@ -441,37 +444,45 @@ class CapaExplorerDataModel(QtCore.QAbstractItemModel):
             self.render_capa_doc_match(parent2, child, doc)
 
     def render_capa_doc_by_function(self, doc: rd.ResultDocument):
-        """ """
-        matches_by_function: Dict[int, Tuple[CapaExplorerFunctionItem, Set[str]]] = {}
+        """render rule matches by function meaning each rule match is nested under function where it was found"""
+        matches_by_function: Dict[AbsoluteVirtualAddress, Tuple[CapaExplorerFunctionItem, Set[str]]] = {}
         for rule in rutils.capability_rules(doc):
-            for location_, _ in rule.matches:
-                location = location_.to_capa()
+            match_eas: List[int] = []
 
-                if not isinstance(location, AbsoluteVirtualAddress):
-                    # only handle matches with a VA
-                    continue
-                ea = int(location)
+            # initial pass of rule matches
+            for addr_, _ in rule.matches:
+                addr: Address = addr_.to_capa()
+                if isinstance(addr, AbsoluteVirtualAddress):
+                    match_eas.append(int(addr))
 
-                ea = capa.ida.helpers.get_func_start_ea(ea)
-                if ea is None:
-                    # file scope, skip rendering in this mode
+            for ea in match_eas:
+                func_ea: Optional[int] = capa.ida.helpers.get_func_start_ea(ea)
+                if func_ea is None:
+                    # rule match address is not located in a defined function
                     continue
-                if not matches_by_function.get(ea, ()):
-                    # new function root
-                    matches_by_function[ea] = (
-                        CapaExplorerFunctionItem(self.root_node, location, can_check=False),
+
+                func_address: AbsoluteVirtualAddress = AbsoluteVirtualAddress(func_ea)
+                if not matches_by_function.get(func_address, ()):
+                    # create a new function root to nest its rule matches; Note: we must use the address of the
+                    # function here so everything is displayed properly
+                    matches_by_function[func_address] = (
+                        CapaExplorerFunctionItem(self.root_node, func_address, can_check=False),
                         set(),
                     )
-                function_root, match_cache = matches_by_function[ea]
-                if rule.meta.name in match_cache:
-                    # rule match already rendered for this function root, skip it
+
+                func_root, func_match_cache = matches_by_function[func_address]
+                if rule.meta.name in func_match_cache:
+                    # only nest each rule once, so if found, skip
                     continue
-                match_cache.add(rule.meta.name)
+
+                # add matched rule to its function cache; create a new rule node whose parent is the matched
+                # function node
+                func_match_cache.add(rule.meta.name)
                 CapaExplorerRuleItem(
-                    function_root,
+                    func_root,
                     rule.meta.name,
                     rule.meta.namespace or "",
-                    len(rule.matches),
+                    len([ea for ea in match_eas if capa.ida.helpers.get_func_start_ea(ea) == func_ea]),
                     rule.source,
                     can_check=False,
                 )
@@ -483,7 +494,7 @@ class CapaExplorerDataModel(QtCore.QAbstractItemModel):
             rule_namespace = rule.meta.namespace or ""
             parent = CapaExplorerRuleItem(self.root_node, rule_name, rule_namespace, len(rule.matches), rule.source)
 
-            for (location_, match) in rule.matches:
+            for location_, match in rule.matches:
                 location = location_.to_capa()
 
                 parent2: CapaExplorerDataItem
@@ -493,6 +504,8 @@ class CapaExplorerDataModel(QtCore.QAbstractItemModel):
                     parent2 = CapaExplorerFunctionItem(parent, location)
                 elif rule.meta.scope == capa.rules.BASIC_BLOCK_SCOPE:
                     parent2 = CapaExplorerBlockItem(parent, location)
+                elif rule.meta.scope == capa.rules.INSTRUCTION_SCOPE:
+                    parent2 = CapaExplorerInstructionItem(parent, location)
                 else:
                     raise RuntimeError("unexpected rule scope: " + str(rule.meta.scope))
 
@@ -520,11 +533,19 @@ class CapaExplorerDataModel(QtCore.QAbstractItemModel):
         @param feature: capa feature read from doc
         """
         key = feature.type
-        value = getattr(feature, feature.type)
+        value = feature.dict(by_alias=True).get(feature.type)
 
         if value:
             if isinstance(feature, frzf.StringFeature):
                 value = '"%s"' % capa.features.common.escape_string(value)
+
+            if isinstance(feature, frzf.PropertyFeature) and feature.access is not None:
+                key = f"property/{feature.access}"
+            elif isinstance(feature, frzf.OperandNumberFeature):
+                key = f"operand[{feature.index}].number"
+            elif isinstance(feature, frzf.OperandOffsetFeature):
+                key = f"operand[{feature.index}].offset"
+
             if feature.description:
                 return "%s(%s = %s)" % (key, value, feature.description)
             else:
@@ -634,6 +655,8 @@ class CapaExplorerDataModel(QtCore.QAbstractItemModel):
                 frzf.MnemonicFeature,
                 frzf.NumberFeature,
                 frzf.OffsetFeature,
+                frzf.OperandNumberFeature,
+                frzf.OperandOffsetFeature,
             ),
         ):
             # display instruction preview

capa/ida/plugin/proxy.py

@@ -22,7 +22,7 @@ class CapaExplorerRangeProxyModel(QtCore.QSortFilterProxyModel):
 
     def __init__(self, parent=None):
         """initialize proxy filter"""
-        super(CapaExplorerRangeProxyModel, self).__init__(parent)
+        super().__init__(parent)
         self.min_ea = None
         self.max_ea = None
 
@@ -92,7 +92,7 @@ class CapaExplorerRangeProxyModel(QtCore.QSortFilterProxyModel):
         @param parent: QModelIndex of parent
         """
         # filter not set
-        if self.min_ea is None and self.max_ea is None:
+        if self.min_ea is None or self.max_ea is None:
             return True
 
         index = self.sourceModel().index(row, 0, parent)
@@ -145,7 +145,7 @@ class CapaExplorerSearchProxyModel(QtCore.QSortFilterProxyModel):
 
     def __init__(self, parent=None):
         """ """
-        super(CapaExplorerSearchProxyModel, self).__init__(parent)
+        super().__init__(parent)
         self.query = ""
         self.setFilterKeyColumn(-1)  # all columns
 

capa/ida/plugin/view.py

@@ -18,7 +18,7 @@ import capa.ida.helpers
 import capa.features.common
 import capa.features.basicblock
 from capa.ida.plugin.item import CapaExplorerFunctionItem
-from capa.features.address import Address, _NoAddress
+from capa.features.address import AbsoluteVirtualAddress, _NoAddress
 from capa.ida.plugin.model import CapaExplorerDataModel
 
 MAX_SECTION_SIZE = 750
@@ -74,7 +74,7 @@ def parse_node_for_feature(feature, description, comment, depth):
     if feature.startswith("#"):
         display += "%s%s\n" % (" " * depth, feature)
     elif description:
-        if feature.startswith(("- and", "- or", "- optional", "- basic block", "- not")):
+        if feature.startswith(("- and", "- or", "- optional", "- basic block", "- not", "- instruction:")):
             display += "%s%s" % (" " * depth, feature)
             if comment:
                 display += " # %s" % comment
@@ -174,16 +174,16 @@ def resize_columns_to_content(header):
 
 
 class CapaExplorerRulegenPreview(QtWidgets.QTextEdit):
-
     INDENT = " " * 2
 
     def __init__(self, parent=None):
         """ """
-        super(CapaExplorerRulegenPreview, self).__init__(parent)
+        super().__init__(parent)
 
         self.setFont(QtGui.QFont("Courier", weight=QtGui.QFont.Bold))
         self.setLineWrapMode(QtWidgets.QTextEdit.NoWrap)
         self.setHorizontalScrollBarPolicy(QtCore.Qt.ScrollBarAsNeeded)
+        self.setAcceptRichText(False)
 
     def reset_view(self):
         """ """
@@ -200,7 +200,8 @@ class CapaExplorerRulegenPreview(QtWidgets.QTextEdit):
             "    authors:",
             "      - %s" % author,
             "    scope: %s" % scope,
-            "    references: <insert_references>",
+            "    references:",
+            "      - <insert_references>",
             "    examples:",
             "      - %s:0x%X" % (capa.ida.helpers.get_file_md5().upper(), ea)
             if ea
@@ -253,7 +254,7 @@ class CapaExplorerRulegenPreview(QtWidgets.QTextEdit):
                     lines_modified = 0
                     first_modified = False
                     change = []
-                    for (lineno, line) in enumerate(plain[start_lineno : end_lineno + 1]):
+                    for lineno, line in enumerate(plain[start_lineno : end_lineno + 1]):
                         if line.startswith(self.INDENT):
                             if lineno == 0:
                                 # keep track if first line is modified, so we can properly display
@@ -284,7 +285,7 @@ class CapaExplorerRulegenPreview(QtWidgets.QTextEdit):
                 self.set_selection(select_start_ppos, select_end_ppos, len(self.toPlainText()))
                 self.verticalScrollBar().setSliderPosition(scroll_ppos)
         else:
-            super(CapaExplorerRulegenPreview, self).keyPressEvent(e)
+            super().keyPressEvent(e)
 
     def count_previous_lines_from_block(self, block):
         """calculate number of lines preceding block"""
@@ -305,12 +306,11 @@ class CapaExplorerRulegenPreview(QtWidgets.QTextEdit):
 
 
 class CapaExplorerRulegenEditor(QtWidgets.QTreeWidget):
-
     updated = QtCore.pyqtSignal()
 
     def __init__(self, preview, parent=None):
         """ """
-        super(CapaExplorerRulegenEditor, self).__init__(parent)
+        super().__init__(parent)
 
         self.preview = preview
 
@@ -374,18 +374,18 @@ class CapaExplorerRulegenEditor(QtWidgets.QTreeWidget):
 
     def dragMoveEvent(self, e):
         """ """
-        super(CapaExplorerRulegenEditor, self).dragMoveEvent(e)
+        super().dragMoveEvent(e)
 
     def dragEventEnter(self, e):
         """ """
-        super(CapaExplorerRulegenEditor, self).dragEventEnter(e)
+        super().dragEventEnter(e)
 
     def dropEvent(self, e):
         """ """
         if not self.indexAt(e.pos()).isValid():
             return
 
-        super(CapaExplorerRulegenEditor, self).dropEvent(e)
+        super().dropEvent(e)
 
         self.update_preview()
         expand_tree(self.invisibleRootItem())
@@ -427,6 +427,10 @@ class CapaExplorerRulegenEditor(QtWidgets.QTreeWidget):
             # add default child expression when nesting under basic block
             new_parent.setExpanded(True)
             new_parent = self.new_expression_node(new_parent, ("- or:", ""))
+        elif "instruction" in action.data()[0]:
+            # add default child expression when nesting under instruction
+            new_parent.setExpanded(True)
+            new_parent = self.new_expression_node(new_parent, ("- or:", ""))
 
         for o in self.get_features(selected=True):
             # take child from its parent by index, add to new parent
@@ -447,6 +451,16 @@ class CapaExplorerRulegenEditor(QtWidgets.QTreeWidget):
             for child in children:
                 new_parent.addChild(child)
             new_parent.setExpanded(True)
+        elif "instruction" in expression and "instruction" not in o.text(
+            CapaExplorerRulegenEditor.get_column_feature_index()
+        ):
+            # current expression is "instruction", and not changing to "instruction" expression
+            children = o.takeChildren()
+            new_parent = self.new_expression_node(o, ("- or:", ""))
+            for child in children:
+                new_parent.addChild(child)
+            new_parent.setExpanded(True)
+
         o.setText(CapaExplorerRulegenEditor.get_column_feature_index(), expression)
 
     def slot_clear_all(self, action):
@@ -520,6 +534,7 @@ class CapaExplorerRulegenEditor(QtWidgets.QTreeWidget):
             ("not", ("- not:",), self.slot_nest_features),
             ("optional", ("- optional:",), self.slot_nest_features),
             ("basic block", ("- basic block:",), self.slot_nest_features),
+            ("instruction", ("- instruction:",), self.slot_nest_features),
         )
 
         # build submenu with modify actions
@@ -541,6 +556,7 @@ class CapaExplorerRulegenEditor(QtWidgets.QTreeWidget):
             ("not", ("- not:", self.itemAt(pos)), self.slot_edit_expression),
             ("optional", ("- optional:", self.itemAt(pos)), self.slot_edit_expression),
             ("basic block", ("- basic block:", self.itemAt(pos)), self.slot_edit_expression),
+            ("instruction", ("- instruction:", self.itemAt(pos)), self.slot_edit_expression),
         )
 
         # build submenu with modify actions
@@ -601,7 +617,7 @@ class CapaExplorerRulegenEditor(QtWidgets.QTreeWidget):
         """ """
         o = QtWidgets.QTreeWidgetItem(parent)
         self.set_expression_node(o)
-        for (i, v) in enumerate(values):
+        for i, v in enumerate(values):
             o.setText(i, v)
         return o
 
@@ -609,7 +625,7 @@ class CapaExplorerRulegenEditor(QtWidgets.QTreeWidget):
         """ """
         o = QtWidgets.QTreeWidgetItem(parent)
         self.set_feature_node(o)
-        for (i, v) in enumerate(values):
+        for i, v in enumerate(values):
             o.setText(i, v)
         return o
 
@@ -617,7 +633,7 @@ class CapaExplorerRulegenEditor(QtWidgets.QTreeWidget):
         """ """
         o = QtWidgets.QTreeWidgetItem(parent)
         self.set_comment_node(o)
-        for (i, v) in enumerate(values):
+        for i, v in enumerate(values):
             o.setText(i, v)
         return o
 
@@ -636,7 +652,7 @@ class CapaExplorerRulegenEditor(QtWidgets.QTreeWidget):
         counted = list(zip(Counter(features).keys(), Counter(features).values()))
 
         # single features
-        for (k, v) in filter(lambda t: t[1] == 1, counted):
+        for k, v in filter(lambda t: t[1] == 1, counted):
             if isinstance(k, (capa.features.common.String,)):
                 value = '"%s"' % capa.features.common.escape_string(k.get_value_str())
             else:
@@ -644,7 +660,7 @@ class CapaExplorerRulegenEditor(QtWidgets.QTreeWidget):
             self.new_feature_node(top_node, ("- %s: %s" % (k.name.lower(), value), ""))
 
         # n > 1 features
-        for (k, v) in filter(lambda t: t[1] > 1, counted):
+        for k, v in filter(lambda t: t[1] > 1, counted):
             if k.value:
                 if isinstance(k, (capa.features.common.String,)):
                     value = '"%s"' % capa.features.common.escape_string(k.get_value_str())
@@ -689,11 +705,11 @@ class CapaExplorerRulegenEditor(QtWidgets.QTreeWidget):
         node = QtWidgets.QTreeWidgetItem(parent)
 
         # set node text to data parsed from feature
-        for (idx, text) in enumerate((feature, comment, description)):
+        for idx, text in enumerate((feature, comment, description)):
             node.setText(idx, text)
 
         # we need to set our own type so we can control the GUI accordingly
-        if feature.startswith(("- and:", "- or:", "- not:", "- basic block:", "- optional:")):
+        if feature.startswith(("- and:", "- or:", "- not:", "- basic block:", "- instruction:", "- optional:")):
             setattr(node, "capa_type", CapaExplorerRulegenEditor.get_node_type_expression())
         elif feature.startswith("#"):
             setattr(node, "capa_type", CapaExplorerRulegenEditor.get_node_type_comment())
@@ -784,7 +800,7 @@ class CapaExplorerRulegenEditor(QtWidgets.QTreeWidget):
 class CapaExplorerRulegenFeatures(QtWidgets.QTreeWidget):
     def __init__(self, editor, parent=None):
         """ """
-        super(CapaExplorerRulegenFeatures, self).__init__(parent)
+        super().__init__(parent)
 
         self.parent_items = {}
         self.editor = editor
@@ -981,7 +997,7 @@ class CapaExplorerRulegenFeatures(QtWidgets.QTreeWidget):
         o = QtWidgets.QTreeWidgetItem(parent)
 
         self.set_parent_node(o)
-        for (i, v) in enumerate(data):
+        for i, v in enumerate(data):
             o.setText(i, v)
         if feature:
             o.setData(0, 0x100, feature)
@@ -993,7 +1009,7 @@ class CapaExplorerRulegenFeatures(QtWidgets.QTreeWidget):
         o = QtWidgets.QTreeWidgetItem(parent)
 
         self.set_leaf_node(o)
-        for (i, v) in enumerate(data):
+        for i, v in enumerate(data):
             o.setText(i, v)
         if feature:
             o.setData(0, 0x100, feature)
@@ -1012,8 +1028,10 @@ class CapaExplorerRulegenFeatures(QtWidgets.QTreeWidget):
         self.parent_items = {}
 
         def format_address(e):
-            assert isinstance(e, Address)
-            return "%X" % e if not isinstance(e, _NoAddress) else ""
+            if isinstance(e, AbsoluteVirtualAddress):
+                return "%X" % int(e)
+            else:
+                return ""
 
         def format_feature(feature):
             """ """
@@ -1023,7 +1041,7 @@ class CapaExplorerRulegenFeatures(QtWidgets.QTreeWidget):
                 value = '"%s"' % capa.features.common.escape_string(value)
             return "%s(%s)" % (name, value)
 
-        for (feature, addrs) in sorted(features.items(), key=lambda k: sorted(k[1])):
+        for feature, addrs in sorted(features.items(), key=lambda k: sorted(k[1])):
             if isinstance(feature, capa.features.basicblock.BasicBlock):
                 # filter basic blocks for now, we may want to add these back in some time
                 # in the future
@@ -1056,7 +1074,7 @@ class CapaExplorerRulegenFeatures(QtWidgets.QTreeWidget):
                 else:
                     # some features may not have an address e.g. "format"
                     addr = _NoAddress()
-                for (i, v) in enumerate((format_feature(feature), format_address(addr))):
+                for i, v in enumerate((format_feature(feature), format_address(addr))):
                     self.parent_items[feature].setText(i, v)
                 self.parent_items[feature].setData(0, 0x100, feature)
 
@@ -1072,7 +1090,7 @@ class CapaExplorerQtreeView(QtWidgets.QTreeView):
 
     def __init__(self, model, parent=None):
         """initialize view"""
-        super(CapaExplorerQtreeView, self).__init__(parent)
+        super().__init__(parent)
 
         self.setModel(model)
 

capa/main.py

@@ -17,11 +17,10 @@ import os.path
 import argparse
 import datetime
 import textwrap
-import warnings
 import itertools
 import contextlib
 import collections
-from typing import Any, Dict, List, Tuple
+from typing import Any, Dict, List, Tuple, Callable
 
 import halo
 import tqdm
@@ -34,6 +33,7 @@ import capa.rules
 import capa.engine
 import capa.version
 import capa.render.json
+import capa.rules.cache
 import capa.render.default
 import capa.render.verbose
 import capa.features.common
@@ -66,25 +66,24 @@ from capa.features.common import (
     FORMAT_DOTNET,
     FORMAT_FREEZE,
 )
-from capa.features.address import NO_ADDRESS
+from capa.features.address import NO_ADDRESS, Address
 from capa.features.extractors.base_extractor import BBHandle, InsnHandle, FunctionHandle, FeatureExtractor
 
 RULES_PATH_DEFAULT_STRING = "(embedded rules)"
 SIGNATURES_PATH_DEFAULT_STRING = "(embedded signatures)"
 BACKEND_VIV = "vivisect"
-BACKEND_SMDA = "smda"
 BACKEND_DOTNET = "dotnet"
 
-E_MISSING_RULES = -10
-E_MISSING_FILE = -11
-E_INVALID_RULE = -12
-E_CORRUPT_FILE = -13
-E_FILE_LIMITATION = -14
-E_INVALID_SIG = -15
-E_INVALID_FILE_TYPE = -16
-E_INVALID_FILE_ARCH = -17
-E_INVALID_FILE_OS = -18
-E_UNSUPPORTED_IDA_VERSION = -19
+E_MISSING_RULES = 10
+E_MISSING_FILE = 11
+E_INVALID_RULE = 12
+E_CORRUPT_FILE = 13
+E_FILE_LIMITATION = 14
+E_INVALID_SIG = 15
+E_INVALID_FILE_TYPE = 16
+E_INVALID_FILE_ARCH = 17
+E_INVALID_FILE_OS = 18
+E_UNSUPPORTED_IDA_VERSION = 19
 
 logger = logging.getLogger("capa")
 
@@ -332,7 +331,7 @@ def has_file_limitation(rules: RuleSet, capabilities: MatchResults, is_standalon
 
         logger.warning("-" * 80)
         for line in file_limitation_rule.meta.get("description", "").split("\n"):
-            logger.warning(" " + line)
+            logger.warning(" %s", line)
         logger.warning(" Identified via rule: %s", file_limitation_rule.name)
         if is_standalone:
             logger.warning(" ")
@@ -433,7 +432,7 @@ def get_default_signatures() -> List[str]:
     logger.debug("signatures path: %s", sigs_path)
 
     ret = []
-    for root, dirs, files in os.walk(sigs_path):
+    for root, _, files in os.walk(sigs_path):
         for file in files:
             if not (file.endswith(".pat") or file.endswith(".pat.gz") or file.endswith(".sig")):
                 continue
@@ -461,6 +460,7 @@ def get_workspace(path, format_, sigpaths):
 
     # lazy import enables us to not require viv if user wants SMDA, for example.
     import viv_utils
+    import viv_utils.flirt
 
     logger.debug("generating vivisect workspace for: %s", path)
     # TODO should not be auto at this point, anymore
@@ -513,22 +513,7 @@ def get_extractor(
 
         return capa.features.extractors.dnfile.extractor.DnfileFeatureExtractor(path)
 
-    if backend == "smda":
-        from smda.SmdaConfig import SmdaConfig
-        from smda.Disassembler import Disassembler
-
-        import capa.features.extractors.smda.extractor
-
-        logger.warning("Deprecation warning: v4.0 will be the last capa version to support the SMDA backend.")
-        warnings.warn("v4.0 will be the last capa version to support the SMDA backend.", DeprecationWarning)
-        smda_report = None
-        with halo.Halo(text="analyzing program", spinner="simpleDots", stream=sys.stderr, enabled=not disable_progress):
-            config = SmdaConfig()
-            config.STORE_BUFFER = True
-            smda_disasm = Disassembler(config)
-            smda_report = smda_disasm.disassembleFile(path)
-
-        return capa.features.extractors.smda.extractor.SmdaFeatureExtractor(smda_report, path)
+    # default to use vivisect backend
     else:
         import capa.features.extractors.viv.extractor
 
@@ -551,12 +536,12 @@ def get_extractor(
 def get_file_extractors(sample: str, format_: str) -> List[FeatureExtractor]:
     file_extractors: List[FeatureExtractor] = list()
 
-    if format_ == capa.features.extractors.common.FORMAT_PE:
+    if format_ == FORMAT_PE:
         file_extractors.append(capa.features.extractors.pefile.PefileFeatureExtractor(sample))
 
-        dnfile_extractor = capa.features.extractors.dnfile_.DnfileFeatureExtractor(sample)
-        if dnfile_extractor.is_dotnet_file():
-            file_extractors.append(dnfile_extractor)
+    elif format_ == FORMAT_DOTNET:
+        file_extractors.append(capa.features.extractors.pefile.PefileFeatureExtractor(sample))
+        file_extractors.append(capa.features.extractors.dnfile_.DnfileFeatureExtractor(sample))
 
     elif format_ == capa.features.extractors.common.FORMAT_ELF:
         file_extractors.append(capa.features.extractors.elffile.ElfFeatureExtractor(sample))
@@ -577,7 +562,10 @@ def is_nursery_rule_path(path: str) -> bool:
     return "nursery" in path
 
 
-def get_rules(rule_paths: List[str], disable_progress=False) -> List[Rule]:
+def collect_rule_file_paths(rule_paths: List[str]) -> List[str]:
+    """
+    collect all rule file paths, including those in subdirectories.
+    """
     rule_file_paths = []
     for rule_path in rule_paths:
         if not os.path.exists(rule_path):
@@ -587,7 +575,7 @@ def get_rules(rule_paths: List[str], disable_progress=False) -> List[Rule]:
             rule_file_paths.append(rule_path)
         elif os.path.isdir(rule_path):
             logger.debug("reading rules from directory %s", rule_path)
-            for root, dirs, files in os.walk(rule_path):
+            for root, _, files in os.walk(rule_path):
                 if ".git" in root:
                     # the .github directory contains CI config in capa-rules
                     # this includes some .yml files
@@ -605,28 +593,69 @@ def get_rules(rule_paths: List[str], disable_progress=False) -> List[Rule]:
                     rule_path = os.path.join(root, file)
                     rule_file_paths.append(rule_path)
 
+    return rule_file_paths
+
+
+# TypeAlias. note: using `foo: TypeAlias = bar` is Python 3.10+
+RulePath = str
+
+
+def on_load_rule_default(_path: RulePath, i: int, _total: int) -> None:
+    return
+
+
+def get_rules(
+    rule_paths: List[RulePath],
+    cache_dir=None,
+    on_load_rule: Callable[[RulePath, int, int], None] = on_load_rule_default,
+) -> RuleSet:
+    """
+    args:
+      rule_paths: list of paths to rules files or directories containing rules files
+      cache_dir: directory to use for caching rules, or will use the default detected cache directory if None
+      on_load_rule: callback to invoke before a rule is loaded, use for progress or cancellation
+    """
+    if cache_dir is None:
+        cache_dir = capa.rules.cache.get_default_cache_directory()
+
+    # rule_paths may contain directory paths,
+    # so search for file paths recursively.
+    rule_file_paths = collect_rule_file_paths(rule_paths)
+
+    # this list is parallel to `rule_file_paths`:
+    # rule_file_paths[i] corresponds to rule_contents[i].
+    rule_contents = []
+    for file_path in rule_file_paths:
+        with open(file_path, "rb") as f:
+            rule_contents.append(f.read())
+
+    ruleset = capa.rules.cache.load_cached_ruleset(cache_dir, rule_contents)
+    if ruleset is not None:
+        return ruleset
+
     rules = []  # type: List[Rule]
 
-    pbar = tqdm.tqdm
-    if disable_progress:
-        # do not use tqdm to avoid unnecessary side effects when caller intends
-        # to disable progress completely
-        pbar = lambda s, *args, **kwargs: s
+    total_rule_count = len(rule_file_paths)
+    for i, (path, content) in enumerate(zip(rule_file_paths, rule_contents)):
+        on_load_rule(path, i, total_rule_count)
 
-    for rule_file_path in pbar(list(rule_file_paths), desc="loading ", unit=" rules"):
         try:
-            rule = capa.rules.Rule.from_yaml_file(rule_file_path)
+            rule = capa.rules.Rule.from_yaml(content.decode("utf-8"))
         except capa.rules.InvalidRule:
             raise
         else:
-            rule.meta["capa/path"] = rule_file_path
-            if is_nursery_rule_path(rule_file_path):
+            rule.meta["capa/path"] = path
+            if is_nursery_rule_path(path):
                 rule.meta["capa/nursery"] = True
 
             rules.append(rule)
             logger.debug("loaded rule: '%s' with scope: %s", rule.name, rule.scope)
 
-    return rules
+    ruleset = capa.rules.RuleSet(rules)
+
+    capa.rules.cache.cache_ruleset(cache_dir, ruleset)
+
+    return ruleset
 
 
 def get_signatures(sigs_path):
@@ -638,7 +667,7 @@ def get_signatures(sigs_path):
         paths.append(sigs_path)
     elif os.path.isdir(sigs_path):
         logger.debug("reading signatures from directory %s", os.path.abspath(os.path.normpath(sigs_path)))
-        for root, dirs, files in os.walk(sigs_path):
+        for root, _, files in os.walk(sigs_path):
             for file in files:
                 if file.endswith((".pat", ".pat.gz", ".sig")):
                     sig_path = os.path.join(root, file)
@@ -717,8 +746,8 @@ def compute_layout(rules, extractor, capabilities):
     otherwise, we may pollute the json document with
     a large amount of un-referenced data.
     """
-    functions_by_bb = {}
-    bbs_by_function = {}
+    functions_by_bb: Dict[Address, Address] = {}
+    bbs_by_function: Dict[Address, List[Address]] = {}
     for f in extractor.get_functions():
         bbs_by_function[f.address] = []
         for bb in extractor.get_basic_blocks(f):
@@ -729,7 +758,7 @@ def compute_layout(rules, extractor, capabilities):
     for rule_name, matches in capabilities.items():
         rule = rules[rule_name]
         if rule.meta.get("scope") == capa.rules.BASIC_BLOCK_SCOPE:
-            for (addr, match) in matches:
+            for addr, _ in matches:
                 assert addr in functions_by_bb
                 matched_bbs.add(addr)
 
@@ -830,7 +859,7 @@ def install_common_args(parser, wanted=None):
                 "--backend",
                 type=str,
                 help="select the backend to use",
-                choices=(BACKEND_VIV, BACKEND_SMDA),
+                choices=(BACKEND_VIV,),
                 default=BACKEND_VIV,
             )
 
@@ -865,6 +894,9 @@ def handle_common_args(args):
       - rules: file system path to rule files.
       - signatures: file system path to signature files.
 
+    the following field may be added:
+      - is_default_rules: if the default rules were used.
+
     args:
       args (argparse.Namespace): parsed arguments that included at least `install_common_args` args.
     """
@@ -924,6 +956,7 @@ def handle_common_args(args):
                 return E_MISSING_RULES
 
             rules_paths.append(default_rule_path)
+            args.is_default_rules = True
         else:
             rules_paths = args.rules
 
@@ -933,6 +966,8 @@ def handle_common_args(args):
             for rule_path in rules_paths:
                 logger.debug("using rules path: %s", rule_path)
 
+            args.is_default_rules = False
+
         args.rules = rules_paths
 
     if hasattr(args, "signatures"):
@@ -1010,20 +1045,27 @@ def main(argv=None):
     if format_ == FORMAT_AUTO:
         try:
             format_ = get_auto_format(args.sample)
+        except PEFormatError as e:
+            logger.error("Input file '%s' is not a valid PE file: %s", args.sample, str(e))
+            return E_CORRUPT_FILE
         except UnsupportedFormatError:
             log_unsupported_format_error()
             return E_INVALID_FILE_TYPE
 
     try:
-        rules = get_rules(args.rules, disable_progress=args.quiet)
-        rules = capa.rules.RuleSet(rules)
+        if is_running_standalone() and args.is_default_rules:
+            cache_dir = os.path.join(get_default_root(), "cache")
+        else:
+            cache_dir = capa.rules.cache.get_default_cache_directory()
+
+        rules = get_rules(args.rules, cache_dir=cache_dir)
 
         logger.debug(
             "successfully loaded %s rules",
             # during the load of the RuleSet, we extract subscope statements into their own rules
             # that are subsequently `match`ed upon. this inflates the total rule count.
             # so, filter out the subscope rules when reporting total number of loaded rules.
-            len([i for i in filter(lambda r: not r.is_subscope_rule(), rules.rules.values())]),
+            len(list(filter(lambda r: not r.is_subscope_rule(), rules.rules.values()))),
         )
         if args.tag:
             rules = rules.filter_rules_by_meta(args.tag)
@@ -1034,12 +1076,12 @@ def main(argv=None):
     except (IOError, capa.rules.InvalidRule, capa.rules.InvalidRuleSet) as e:
         logger.error("%s", str(e))
         logger.error(
-            "Please ensure you're using the rules that correspond to your major version of capa (%s)",
-            capa.version.get_major_version(),
+            "Make sure your file directory contains properly formatted capa rules. You can download the standard "
+            "collection of capa rules from https://github.com/mandiant/capa-rules/releases."
         )
         logger.error(
-            "You can check out these rules with the following command:\n    %s",
-            capa.version.get_rules_checkout_command(),
+            "Please ensure you're using the rules that correspond to your major version of capa (%s)",
+            capa.version.get_major_version(),
         )
         logger.error(
             "Or, for more details, see the rule set documentation here: %s",
@@ -1073,9 +1115,6 @@ def main(argv=None):
             logger.error("Input file '%s' is not a valid ELF file: %s", args.sample, str(e))
             return E_CORRUPT_FILE
 
-        if isinstance(file_extractor, capa.features.extractors.dnfile_.DnfileFeatureExtractor):
-            format_ = FORMAT_DOTNET
-
         # file limitations that rely on non-file scope won't be detected here.
         # nor on FunctionName features, because pefile doesn't support this.
         if has_file_limitation(rules, pure_file_capabilities):
@@ -1166,8 +1205,7 @@ def ida_main():
 
     rules_path = os.path.join(get_default_root(), "rules")
     logger.debug("rule path: %s", rules_path)
-    rules = get_rules(rules_path)
-    rules = capa.rules.RuleSet(rules)
+    rules = get_rules([rules_path])
 
     meta = capa.ida.helpers.collect_metadata([rules_path])
 

capa/optimizer.py

@@ -47,7 +47,7 @@ def optimize_statement(statement):
 
     if isinstance(statement, (ceng.And, ceng.Or, ceng.Some)):
         # has .children
-        statement.children = sorted(statement.children, key=lambda n: get_node_cost(n))
+        statement.children = sorted(statement.children, key=get_node_cost)
         return
     elif isinstance(statement, (ceng.Not, ceng.Range)):
         # has .child

capa/perf.py

@@ -1,8 +1,8 @@
+import typing
 import collections
-from typing import Dict
 
 # this structure is unstable and may change before the next major release.
-counters: Dict[str, int] = collections.Counter()
+counters: typing.Counter[str] = collections.Counter()
 
 
 def reset():

capa/render/default.py

@@ -133,7 +133,7 @@ def render_attack(doc: rd.ResultDocument, ostream: StringIO):
     rows = []
     for tactic, techniques in sorted(tactics.items()):
         inner_rows = []
-        for (technique, subtechnique, id) in sorted(techniques):
+        for technique, subtechnique, id in sorted(techniques):
             if not subtechnique:
                 inner_rows.append("%s %s" % (rutils.bold(technique), id))
             else:
@@ -176,7 +176,7 @@ def render_mbc(doc: rd.ResultDocument, ostream: StringIO):
     rows = []
     for objective, behaviors in sorted(objectives.items()):
         inner_rows = []
-        for (behavior, method, id) in sorted(behaviors):
+        for behavior, method, id in sorted(behaviors):
             if not method:
                 inner_rows.append("%s [%s]" % (rutils.bold(behavior), id))
             else:

capa/render/result_document.py

@@ -15,6 +15,7 @@ import capa.engine
 import capa.features.common
 import capa.features.freeze as frz
 import capa.features.address
+import capa.features.freeze.features as frzf
 from capa.rules import RuleSet
 from capa.engine import MatchResults
 from capa.helpers import assert_never
@@ -75,7 +76,7 @@ class Analysis(FrozenModel):
 class Metadata(FrozenModel):
     timestamp: datetime.datetime
     version: str
-    argv: Tuple[str, ...]
+    argv: Optional[Tuple[str, ...]]
     sample: Sample
     analysis: Analysis
 
@@ -99,64 +100,56 @@ class Metadata(FrozenModel):
                 rules=meta["analysis"]["rules"],
                 base_address=frz.Address.from_capa(meta["analysis"]["base_address"]),
                 layout=Layout(
-                    functions=[
+                    functions=tuple(
                         FunctionLayout(
                             address=frz.Address.from_capa(address),
-                            matched_basic_blocks=[
+                            matched_basic_blocks=tuple(
                                 BasicBlockLayout(address=frz.Address.from_capa(bb)) for bb in f["matched_basic_blocks"]
-                            ],
+                            ),
                         )
                         for address, f in meta["analysis"]["layout"]["functions"].items()
-                    ]
+                    )
                 ),
                 feature_counts=FeatureCounts(
                     file=meta["analysis"]["feature_counts"]["file"],
-                    functions=[
+                    functions=tuple(
                         FunctionFeatureCount(address=frz.Address.from_capa(address), count=count)
                         for address, count in meta["analysis"]["feature_counts"]["functions"].items()
-                    ],
+                    ),
                 ),
-                library_functions=[
+                library_functions=tuple(
                     LibraryFunction(address=frz.Address.from_capa(address), name=name)
                     for address, name in meta["analysis"]["library_functions"].items()
-                ],
+                ),
             ),
         )
 
 
+class CompoundStatementType:
+    AND = "and"
+    OR = "or"
+    NOT = "not"
+    OPTIONAL = "optional"
+
+
 class StatementModel(FrozenModel):
     ...
 
 
-class AndStatement(StatementModel):
-    type = "and"
-    description: Optional[str]
-
-
-class OrStatement(StatementModel):
-    type = "or"
-    description: Optional[str]
-
-
-class NotStatement(StatementModel):
-    type = "not"
-    description: Optional[str]
+class CompoundStatement(StatementModel):
+    type: str
+    description: Optional[str] = None
 
 
 class SomeStatement(StatementModel):
     type = "some"
-    description: Optional[str]
+    description: Optional[str] = None
     count: int
 
 
-class OptionalStatement(StatementModel):
-    type = "optional"
-    description: Optional[str]
-
-
 class RangeStatement(StatementModel):
     type = "range"
-    description: Optional[str]
+    description: Optional[str] = None
     min: int
     max: int
     child: frz.Feature
@@ -164,18 +157,16 @@ class RangeStatement(StatementModel):
 
 class SubscopeStatement(StatementModel):
     type = "subscope"
-    description: Optional[str]
-    scope = capa.rules.Scope
+    description: Optional[str] = None
+    scope: capa.rules.Scope
 
 
 Statement = Union[
-    OptionalStatement,
-    AndStatement,
-    OrStatement,
-    NotStatement,
-    SomeStatement,
+    # Note! order matters, see #1161
     RangeStatement,
+    SomeStatement,
     SubscopeStatement,
+    CompoundStatement,
 ]
 
 
@@ -185,18 +176,12 @@ class StatementNode(FrozenModel):
 
 
 def statement_from_capa(node: capa.engine.Statement) -> Statement:
-    if isinstance(node, capa.engine.And):
-        return AndStatement(description=node.description)
-
-    elif isinstance(node, capa.engine.Or):
-        return OrStatement(description=node.description)
-
-    elif isinstance(node, capa.engine.Not):
-        return NotStatement(description=node.description)
+    if isinstance(node, (capa.engine.And, capa.engine.Or, capa.engine.Not)):
+        return CompoundStatement(type=node.__class__.__name__.lower(), description=node.description)
 
     elif isinstance(node, capa.engine.Some):
         if node.count == 0:
-            return OptionalStatement(description=node.description)
+            return CompoundStatement(type=CompoundStatementType.OPTIONAL, description=node.description)
 
         else:
             return SomeStatement(
@@ -293,7 +278,7 @@ class Match(BaseModel):
         # finally, splice that logic into this tree.
         if (
             isinstance(node, FeatureNode)
-            and isinstance(node.feature, frz.features.MatchFeature)
+            and isinstance(node.feature, frzf.MatchFeature)
             # only add subtree on success,
             # because there won't be results for the other rule on failure.
             and success
@@ -375,14 +360,14 @@ class Match(BaseModel):
 
 
 def parse_parts_id(s: str):
-    id = ""
+    id_ = ""
     parts = s.split("::")
     if len(parts) > 0:
         last = parts.pop()
-        last, _, id = last.rpartition(" ")
-        id = id.lstrip("[").rstrip("]")
+        last, _, id_ = last.rpartition(" ")
+        id_ = id_.lstrip("[").rstrip("]")
         parts.append(last)
-    return parts, id
+    return tuple(parts), id_
 
 
 class AttackSpec(FrozenModel):
@@ -408,7 +393,7 @@ class AttackSpec(FrozenModel):
         tactic = ""
         technique = ""
         subtechnique = ""
-        parts, id = parse_parts_id(s)
+        parts, id_ = parse_parts_id(s)
         if len(parts) > 0:
             tactic = parts[0]
         if len(parts) > 1:
@@ -421,7 +406,7 @@ class AttackSpec(FrozenModel):
             tactic=tactic,
             technique=technique,
             subtechnique=subtechnique,
-            id=id,
+            id=id_,
         )
 
 
@@ -448,7 +433,7 @@ class MBCSpec(FrozenModel):
         objective = ""
         behavior = ""
         method = ""
-        parts, id = parse_parts_id(s)
+        parts, id_ = parse_parts_id(s)
         if len(parts) > 0:
             objective = parts[0]
         if len(parts) > 1:
@@ -461,7 +446,7 @@ class MBCSpec(FrozenModel):
             objective=objective,
             behavior=behavior,
             method=method,
-            id=id,
+            id=id_,
         )
 
 
@@ -548,10 +533,10 @@ class ResultDocument(BaseModel):
             rule_matches[rule_name] = RuleMatches(
                 meta=RuleMetadata.from_capa(rule),
                 source=rule.definition,
-                matches=[
+                matches=tuple(
                     (frz.Address.from_capa(addr), Match.from_capa(rules, capabilities, match))
                     for addr, match in matches
-                ],
+                ),
             )
 
         return ResultDocument(meta=Metadata.from_capa(meta), rules=rule_matches)

capa/render/utils.py

@@ -24,12 +24,8 @@ def bold2(s: str) -> str:
     return termcolor.colored(s, "green")
 
 
-def hex(n: int) -> str:
-    """render the given number using upper case hex, like: 0x123ABC"""
-    if n < 0:
-        return "-0x%X" % (-n)
-    else:
-        return "0x%X" % n
+def warn(s: str) -> str:
+    return termcolor.colored(s, "yellow")
 
 
 def format_parts_id(data: Union[rd.AttackSpec, rd.MBCSpec]):
@@ -41,7 +37,7 @@ def format_parts_id(data: Union[rd.AttackSpec, rd.MBCSpec]):
 
 def capability_rules(doc: rd.ResultDocument) -> Iterator[rd.RuleMatches]:
     """enumerate the rules in (namespace, name) order that are 'capability' rules (not lib/subscope/disposition/etc)."""
-    for (_, _, rule) in sorted(map(lambda rule: (rule.meta.namespace or "", rule.meta.name, rule), doc.rules.values())):
+    for _, _, rule in sorted(map(lambda rule: (rule.meta.namespace or "", rule.meta.name, rule), doc.rules.values())):
         if rule.meta.lib:
             continue
         if rule.meta.is_subscope_rule:

capa/render/verbose.py

@@ -22,14 +22,14 @@ Unless required by applicable law or agreed to in writing, software distributed
  is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and limitations under the License.
 """
+import enum
+
 import tabulate
-import dnfile.mdtable
-import dncil.clr.token
 
 import capa.rules
+import capa.helpers
 import capa.render.utils as rutils
 import capa.features.freeze as frz
-import capa.render.result_document
 import capa.render.result_document as rd
 from capa.rules import RuleSet
 from capa.engine import MatchResults
@@ -37,18 +37,23 @@ from capa.engine import MatchResults
 
 def format_address(address: frz.Address) -> str:
     if address.type == frz.AddressType.ABSOLUTE:
-        return rutils.hex(address.value)
+        assert isinstance(address.value, int)
+        return capa.helpers.hex(address.value)
     elif address.type == frz.AddressType.RELATIVE:
-        return f"base address+{rutils.hex(address.value)}"
+        assert isinstance(address.value, int)
+        return f"base address+{capa.helpers.hex(address.value)}"
     elif address.type == frz.AddressType.FILE:
-        return f"file+{rutils.hex(address.value)}"
+        assert isinstance(address.value, int)
+        return f"file+{capa.helpers.hex(address.value)}"
     elif address.type == frz.AddressType.DN_TOKEN:
-        token = dncil.clr.token.Token(address.value)
-        return f"token({rutils.hex(token.value)})"
+        assert isinstance(address.value, int)
+        return f"token({capa.helpers.hex(address.value)})"
     elif address.type == frz.AddressType.DN_TOKEN_OFFSET:
+        assert isinstance(address.value, tuple)
         token, offset = address.value
-        token = dncil.clr.token.Token(token)
-        return f"token({rutils.hex(token.value)})+{rutils.hex(offset)}"
+        assert isinstance(token, int)
+        assert isinstance(offset, int)
+        return f"token({capa.helpers.hex(token)})+{capa.helpers.hex(offset)}"
     elif address.type == frz.AddressType.NO_ADDRESS:
         return "global"
     else:
@@ -130,6 +135,9 @@ def render_rules(ostream, doc: rd.ResultDocument):
             if isinstance(v, list) and len(v) == 1:
                 v = v[0]
 
+            if isinstance(v, enum.Enum):
+                v = v.value
+
             rows.append((key, v))
 
         if rule.meta.scope != capa.rules.FILE_SCOPE:

capa/render/vverbose.py

@@ -6,11 +6,12 @@
 #  is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and limitations under the License.
 
-from typing import Dict, List, Iterable
+from typing import Dict, Iterable
 
 import tabulate
 
 import capa.rules
+import capa.helpers
 import capa.render.utils as rutils
 import capa.render.verbose
 import capa.features.common
@@ -64,7 +65,7 @@ def render_statement(ostream, match: rd.Match, statement: rd.Statement, indent=0
             ostream.write(" = %s" % statement.description)
         ostream.writeln("")
 
-    elif isinstance(statement, (rd.AndStatement, rd.OrStatement, rd.OptionalStatement, rd.NotStatement)):
+    elif isinstance(statement, (rd.CompoundStatement)):
         # emit `and:`  `or:`  `optional:`  `not:`
         ostream.write(statement.type)
 
@@ -87,7 +88,7 @@ def render_statement(ostream, match: rd.Match, statement: rd.Statement, indent=0
         # so, we have to inline some of the feature rendering here.
 
         child = statement.child
-        value = getattr(child, child.type)
+        value = child.dict(by_alias=True).get(child.type)
 
         if value:
             if isinstance(child, frzf.StringFeature):
@@ -128,26 +129,44 @@ def render_feature(ostream, match: rd.Match, feature: frzf.Feature, indent=0):
     ostream.write("  " * indent)
 
     key = feature.type
-    if isinstance(feature, frzf.ImportFeature):
+    if isinstance(feature, frzf.BasicBlockFeature):
+        # i don't think it makes sense to have standalone basic block features.
+        # we don't parse them from rules, only things like: `count(basic block) > 1`
+        raise ValueError("cannot render basic block feature directly")
+    elif isinstance(feature, frzf.ImportFeature):
         # fixup access to Python reserved name
         value = feature.import_
-    if isinstance(feature, frzf.ClassFeature):
+    elif isinstance(feature, frzf.ClassFeature):
         value = feature.class_
     else:
-        value = getattr(feature, key)
+        # convert attributes to dictionary using aliased names, if applicable
+        value = feature.dict(by_alias=True).get(key, None)
 
-    if key not in ("regex", "substring"):
+    if value is None:
+        raise ValueError("%s contains None" % key)
+
+    if not isinstance(feature, (frzf.RegexFeature, frzf.SubstringFeature)):
         # like:
         #   number: 10 = SOME_CONSTANT @ 0x401000
-        if key == "string":
+        if isinstance(feature, frzf.StringFeature):
             value = render_string_value(value)
 
-        if key == "number":
+        elif isinstance(
+            feature, (frzf.NumberFeature, frzf.OffsetFeature, frzf.OperandNumberFeature, frzf.OperandOffsetFeature)
+        ):
             assert isinstance(value, int)
-            value = hex(value)
+            value = capa.helpers.hex(value)
 
-        ostream.write(key)
-        ostream.write(": ")
+        if isinstance(feature, frzf.PropertyFeature) and feature.access is not None:
+            key = f"property/{feature.access}"
+
+        elif isinstance(feature, frzf.OperandNumberFeature):
+            key = f"operand[{feature.index}].number"
+
+        elif isinstance(feature, frzf.OperandOffsetFeature):
+            key = f"operand[{feature.index}].offset"
+
+        ostream.write(f"{key}: ")
 
         if value:
             ostream.write(rutils.bold2(value))
@@ -156,7 +175,7 @@ def render_feature(ostream, match: rd.Match, feature: frzf.Feature, indent=0):
                 ostream.write(capa.rules.DESCRIPTION_SEPARATOR)
                 ostream.write(feature.description)
 
-        if key not in ("os", "arch"):
+        if not isinstance(feature, (frzf.OSFeature, frzf.ArchFeature, frzf.FormatFeature)):
             render_locations(ostream, match.locations)
         ostream.write("\n")
     else:
@@ -202,12 +221,12 @@ def render_match(ostream, match: rd.Match, indent=0, mode=MODE_SUCCESS):
             return
 
         # optional statement with no successful children is empty
-        if isinstance(match.node, rd.StatementNode) and isinstance(match.node.statement, rd.OptionalStatement):
+        if isinstance(match.node, rd.StatementNode) and match.node.statement.type == rd.CompoundStatementType.OPTIONAL:
             if not any(map(lambda m: m.success, match.children)):
                 return
 
         # not statement, so invert the child mode to show failed evaluations
-        if isinstance(match.node, rd.StatementNode) and isinstance(match.node.statement, rd.NotStatement):
+        if isinstance(match.node, rd.StatementNode) and match.node.statement.type == rd.CompoundStatementType.NOT:
             child_mode = MODE_FAILURE
 
     elif mode == MODE_FAILURE:
@@ -216,12 +235,12 @@ def render_match(ostream, match: rd.Match, indent=0, mode=MODE_SUCCESS):
             return
 
         # optional statement with successful children is not relevant
-        if isinstance(match.node, rd.StatementNode) and isinstance(match.node.statement, rd.OptionalStatement):
+        if isinstance(match.node, rd.StatementNode) and match.node.statement.type == rd.CompoundStatementType.OPTIONAL:
             if any(map(lambda m: m.success, match.children)):
                 return
 
         # not statement, so invert the child mode to show successful evaluations
-        if isinstance(match.node, rd.StatementNode) and isinstance(match.node.statement, rd.NotStatement):
+        if isinstance(match.node, rd.StatementNode) and match.node.statement.type == rd.CompoundStatementType.NOT:
             child_mode = MODE_SUCCESS
     else:
         raise RuntimeError("unexpected mode: " + mode)
@@ -258,7 +277,7 @@ def render_rules(ostream, doc: rd.ResultDocument):
 
     had_match = False
 
-    for (_, _, rule) in sorted(map(lambda rule: (rule.meta.namespace or "", rule.meta.name, rule), doc.rules.values())):
+    for _, _, rule in sorted(map(lambda rule: (rule.meta.namespace or "", rule.meta.name, rule), doc.rules.values())):
         # default scope hides things like lib rules, malware-category rules, etc.
         # but in vverbose mode, we really want to show everything.
         #
@@ -266,17 +285,24 @@ def render_rules(ostream, doc: rd.ResultDocument):
         if rule.meta.is_subscope_rule:
             continue
 
+        lib_info = ""
         count = len(rule.matches)
         if count == 1:
-            capability = rutils.bold(rule.meta.name)
+            if rule.meta.lib:
+                lib_info = " (library rule)"
+            capability = "%s%s" % (rutils.bold(rule.meta.name), lib_info)
         else:
-            capability = "%s (%d matches)" % (rutils.bold(rule.meta.name), count)
+            if rule.meta.lib:
+                lib_info = ", only showing first match of library rule"
+            capability = "%s (%d matches%s)" % (rutils.bold(rule.meta.name), count, lib_info)
 
         ostream.writeln(capability)
         had_match = True
 
         rows = []
-        rows.append(("namespace", rule.meta.namespace))
+        if not rule.meta.lib:
+            # library rules should not have a namespace
+            rows.append(("namespace", rule.meta.namespace))
 
         if rule.meta.maec.analysis_conclusion or rule.meta.maec.analysis_conclusion_ov:
             rows.append(
@@ -289,7 +315,7 @@ def render_rules(ostream, doc: rd.ResultDocument):
         if rule.meta.maec.malware_family:
             rows.append(("maec/malware-family", rule.meta.maec.malware_family))
 
-        if rule.meta.maec.malware_category or rule.meta.maec.malware_category:
+        if rule.meta.maec.malware_category or rule.meta.maec.malware_category_ov:
             rows.append(
                 ("maec/malware-category", rule.meta.maec.malware_category or rule.meta.maec.malware_category_ov)
             )
@@ -336,6 +362,10 @@ def render_rules(ostream, doc: rd.ResultDocument):
 
                 ostream.write("\n")
                 render_match(ostream, match, indent=1)
+                if rule.meta.lib:
+                    # only show first match
+                    break
+
         ostream.write("\n")
 
     if not had_match:

capa/rules/__init__.py

@@ -27,7 +27,9 @@ except ImportError:
 from typing import Any, Set, Dict, List, Tuple, Union, Iterator
 
 import yaml
+import pydantic
 import ruamel.yaml
+import yaml.parser
 
 import capa.perf
 import capa.engine as ceng
@@ -122,6 +124,7 @@ SUPPORTED_FEATURES: Dict[str, Set] = {
     INSTRUCTION_SCOPE: {
         capa.features.common.MatchedRule,
         capa.features.insn.API,
+        capa.features.insn.Property,
         capa.features.insn.Number,
         capa.features.common.String,
         capa.features.common.Bytes,
@@ -156,7 +159,7 @@ SUPPORTED_FEATURES[FUNCTION_SCOPE].update(SUPPORTED_FEATURES[BASIC_BLOCK_SCOPE])
 
 class InvalidRule(ValueError):
     def __init__(self, msg):
-        super(InvalidRule, self).__init__()
+        super().__init__()
         self.msg = msg
 
     def __str__(self):
@@ -168,7 +171,7 @@ class InvalidRule(ValueError):
 
 class InvalidRuleWithPath(InvalidRule):
     def __init__(self, path, msg):
-        super(InvalidRuleWithPath, self).__init__(msg)
+        super().__init__(msg)
         self.path = path
         self.msg = msg
         self.__cause__ = None
@@ -179,7 +182,7 @@ class InvalidRuleWithPath(InvalidRule):
 
 class InvalidRuleSet(ValueError):
     def __init__(self, msg):
-        super(InvalidRuleSet, self).__init__()
+        super().__init__()
         self.msg = msg
 
     def __str__(self):
@@ -231,23 +234,23 @@ def parse_range(s: str):
     min_spec = min_spec.strip()
     max_spec = max_spec.strip()
 
-    min = None
+    min_ = None
     if min_spec:
-        min = parse_int(min_spec)
-        if min < 0:
+        min_ = parse_int(min_spec)
+        if min_ < 0:
             raise InvalidRule("range min less than zero")
 
-    max = None
+    max_ = None
     if max_spec:
-        max = parse_int(max_spec)
-        if max < 0:
+        max_ = parse_int(max_spec)
+        if max_ < 0:
             raise InvalidRule("range max less than zero")
 
-    if min is not None and max is not None:
-        if max < min:
+    if min_ is not None and max_ is not None:
+        if max_ < min_:
             raise InvalidRule("range max less than min")
 
-    return min, max
+    return min_, max_
 
 
 def parse_feature(key: str):
@@ -290,6 +293,8 @@ def parse_feature(key: str):
         return capa.features.common.Class
     elif key == "namespace":
         return capa.features.common.Namespace
+    elif key == "property":
+        return capa.features.insn.Property
     else:
         raise InvalidRule("unexpected statement: %s" % key)
 
@@ -535,14 +540,15 @@ def build_statements(d, scope: str):
         index = key[len("operand[") : -len("].number")]
         try:
             index = int(index)
-        except ValueError:
-            raise InvalidRule("operand index must be an integer")
+        except ValueError as e:
+            raise InvalidRule("operand index must be an integer") from e
 
         value, description = parse_description(d[key], key, d.get("description"))
+        assert isinstance(value, int)
         try:
             feature = capa.features.insn.OperandNumber(index, value, description=description)
         except ValueError as e:
-            raise InvalidRule(str(e))
+            raise InvalidRule(str(e)) from e
         ensure_feature_valid_for_scope(scope, feature)
         return feature
 
@@ -550,14 +556,15 @@ def build_statements(d, scope: str):
         index = key[len("operand[") : -len("].offset")]
         try:
             index = int(index)
-        except ValueError:
-            raise InvalidRule("operand index must be an integer")
+        except ValueError as e:
+            raise InvalidRule("operand index must be an integer") from e
 
         value, description = parse_description(d[key], key, d.get("description"))
+        assert isinstance(value, int)
         try:
             feature = capa.features.insn.OperandOffset(index, value, description=description)
         except ValueError as e:
-            raise InvalidRule(str(e))
+            raise InvalidRule(str(e)) from e
         ensure_feature_valid_for_scope(scope, feature)
         return feature
 
@@ -567,13 +574,27 @@ def build_statements(d, scope: str):
         or (key == "arch" and d[key] not in capa.features.common.VALID_ARCH)
     ):
         raise InvalidRule("unexpected %s value %s" % (key, d[key]))
+
+    elif key.startswith("property/"):
+        access = key[len("property/") :]
+        if access not in capa.features.common.VALID_FEATURE_ACCESS:
+            raise InvalidRule("unexpected %s access %s" % (key, access))
+
+        value, description = parse_description(d[key], key, d.get("description"))
+        try:
+            feature = capa.features.insn.Property(value, access=access, description=description)
+        except ValueError as e:
+            raise InvalidRule(str(e)) from e
+        ensure_feature_valid_for_scope(scope, feature)
+        return feature
+
     else:
         Feature = parse_feature(key)
         value, description = parse_description(d[key], key, d.get("description"))
         try:
             feature = Feature(value, description=description)
         except ValueError as e:
-            raise InvalidRule(str(e))
+            raise InvalidRule(str(e)) from e
         ensure_feature_valid_for_scope(scope, feature)
         return feature
 
@@ -588,7 +609,7 @@ def second(s: List[Any]) -> Any:
 
 class Rule:
     def __init__(self, name: str, scope: str, statement: Statement, meta, definition=""):
-        super(Rule, self).__init__()
+        super().__init__()
         self.name = name
         self.scope = scope
         self.statement = statement
@@ -614,7 +635,7 @@ class Rule:
         Returns:
           List[str]: names of rules upon which this rule depends.
         """
-        deps = set([])
+        deps: Set[str] = set([])
 
         def rec(statement):
             if isinstance(statement, capa.features.common.MatchedRule):
@@ -631,6 +652,7 @@ class Rule:
                     deps.update(map(lambda r: r.name, namespaces[statement.value]))
                 else:
                     # not a namespace, assume its a rule name.
+                    assert isinstance(statement.value, str)
                     deps.add(statement.value)
 
             elif isinstance(statement, ceng.Statement):
@@ -646,7 +668,11 @@ class Rule:
     def _extract_subscope_rules_rec(self, statement):
         if isinstance(statement, ceng.Statement):
             # for each child that is a subscope,
-            for subscope in filter(lambda statement: isinstance(statement, ceng.Subscope), statement.get_children()):
+            for child in statement.get_children():
+                if not isinstance(child, ceng.Subscope):
+                    continue
+
+                subscope = child
 
                 # create a new rule from it.
                 # the name is a randomly generated, hopefully unique value.
@@ -717,7 +743,7 @@ class Rule:
         return self.statement.evaluate(features, short_circuit=short_circuit)
 
     @classmethod
-    def from_dict(cls, d, definition):
+    def from_dict(cls, d: Dict[str, Any], definition: str) -> "Rule":
         meta = d["rule"]["meta"]
         name = meta["name"]
         # if scope is not specified, default to function scope.
@@ -751,14 +777,12 @@ class Rule:
             # prefer to use CLoader to be fast, see #306
             # on Linux, make sure you install libyaml-dev or similar
             # on Windows, get WHLs from pyyaml.org/pypi
-            loader = yaml.CLoader
             logger.debug("using libyaml CLoader.")
+            return yaml.CLoader
         except:
-            loader = yaml.Loader
             logger.debug("unable to import libyaml CLoader, falling back to Python yaml parser.")
             logger.debug("this will be slower to load rules.")
-
-        return loader
+            return yaml.Loader
 
     @staticmethod
     def _get_ruamel_yaml_parser():
@@ -770,8 +794,9 @@ class Rule:
         # use block mode, not inline json-like mode
         y.default_flow_style = False
 
-        # leave quotes unchanged
-        y.preserve_quotes = True
+        # leave quotes unchanged.
+        # manually verified this property exists, even if mypy complains.
+        y.preserve_quotes = True  # type: ignore
 
         # indent lists by two spaces below their parent
         #
@@ -782,12 +807,13 @@ class Rule:
         y.indent(sequence=2, offset=2)
 
         # avoid word wrapping
-        y.width = 4096
+        # manually verified this property exists, even if mypy complains.
+        y.width = 4096  # type: ignore
 
         return y
 
     @classmethod
-    def from_yaml(cls, s, use_ruamel=False):
+    def from_yaml(cls, s: str, use_ruamel=False) -> "Rule":
         if use_ruamel:
             # ruamel enables nice formatting and doc roundtripping with comments
             doc = cls._get_ruamel_yaml_parser().load(s)
@@ -797,14 +823,24 @@ class Rule:
         return cls.from_dict(doc, s)
 
     @classmethod
-    def from_yaml_file(cls, path, use_ruamel=False):
+    def from_yaml_file(cls, path, use_ruamel=False) -> "Rule":
         with open(path, "rb") as f:
             try:
-                return cls.from_yaml(f.read().decode("utf-8"), use_ruamel=use_ruamel)
-            except InvalidRule as e:
-                raise InvalidRuleWithPath(path, str(e))
+                rule = cls.from_yaml(f.read().decode("utf-8"), use_ruamel=use_ruamel)
+                # import here to avoid circular dependency
+                from capa.render.result_document import RuleMetadata
 
-    def to_yaml(self):
+                # validate meta data fields
+                _ = RuleMetadata.from_capa(rule)
+                return rule
+            except InvalidRule as e:
+                raise InvalidRuleWithPath(path, str(e)) from e
+            except pydantic.ValidationError as e:
+                raise InvalidRuleWithPath(path, str(e)) from e
+            except yaml.parser.ParserError as e:
+                raise InvalidRuleWithPath(path, str(e)) from e
+
+    def to_yaml(self) -> str:
         # reformat the yaml document with a common style.
         # this includes:
         #  - ordering the meta elements
@@ -1041,10 +1077,18 @@ class RuleSet:
     """
 
     def __init__(self, rules: List[Rule]):
-        super(RuleSet, self).__init__()
+        super().__init__()
 
         ensure_rules_are_unique(rules)
 
+        # in the next step we extract subscope rules,
+        # which may inflate the number of rules tracked in this ruleset.
+        # so record number of rules initially provided to this ruleset.
+        #
+        # this number is really only meaningful to the user,
+        # who may compare it against the number of files on their file system.
+        self.source_rule_count = len(rules)
+
         rules = self._extract_subscope_rules(rules)
 
         ensure_rule_dependencies_are_met(rules)
@@ -1233,7 +1277,7 @@ class RuleSet:
         return (easy_rules_by_feature, hard_rules)
 
     @staticmethod
-    def _get_rules_for_scope(rules, scope):
+    def _get_rules_for_scope(rules, scope) -> List[Rule]:
         """
         given a collection of rules, collect the rules that are needed at the given scope.
         these rules are ordered topologically.
@@ -1241,7 +1285,7 @@ class RuleSet:
         don't include auto-generated "subscope" rules.
         we want to include general "lib" rules here - even if they are not dependencies of other rules, see #398
         """
-        scope_rules = set([])
+        scope_rules: Set[Rule] = set([])
 
         # we need to process all rules, not just rules with the given scope.
         # this is because rules with a higher scope, e.g. file scope, may have subscope rules
@@ -1255,7 +1299,7 @@ class RuleSet:
         return get_rules_with_scope(topologically_order_rules(list(scope_rules)), scope)
 
     @staticmethod
-    def _extract_subscope_rules(rules):
+    def _extract_subscope_rules(rules) -> List[Rule]:
         """
         process the given sequence of rules.
         for each one, extract any embedded subscope rules into their own rule.
@@ -1291,13 +1335,13 @@ class RuleSet:
             for k, v in rule.meta.items():
                 if isinstance(v, str) and tag in v:
                     logger.debug('using rule "%s" and dependencies, found tag in meta.%s: %s', rule.name, k, v)
-                    rules_filtered.update(set(capa.rules.get_rules_and_dependencies(rules, rule.name)))
+                    rules_filtered.update(set(get_rules_and_dependencies(rules, rule.name)))
                     break
                 if isinstance(v, list):
                     for vv in v:
                         if tag in vv:
                             logger.debug('using rule "%s" and dependencies, found tag in meta.%s: %s', rule.name, k, vv)
-                            rules_filtered.update(set(capa.rules.get_rules_and_dependencies(rules, rule.name)))
+                            rules_filtered.update(set(get_rules_and_dependencies(rules, rule.name)))
                             break
         return RuleSet(list(rules_filtered))
 

capa/rules/cache.py

@@ -0,0 +1,155 @@
+import sys
+import zlib
+import pickle
+import hashlib
+import logging
+import os.path
+from typing import List, Optional
+from dataclasses import dataclass
+
+import capa.rules
+import capa.helpers
+import capa.version
+
+logger = logging.getLogger(__name__)
+
+
+# TypeAlias. note: using `foo: TypeAlias = bar` is Python 3.10+
+CacheIdentifier = str
+
+
+def compute_cache_identifier(rule_content: List[bytes]) -> CacheIdentifier:
+    hash = hashlib.sha256()
+
+    # note that this changes with each release,
+    # so cache identifiers will never collide across releases.
+    version = capa.version.__version__
+
+    hash.update(version.encode("utf-8"))
+    hash.update(b"\x00")
+
+    rule_hashes = list(sorted([hashlib.sha256(buf).hexdigest() for buf in rule_content]))
+    for rule_hash in rule_hashes:
+        hash.update(rule_hash.encode("ascii"))
+        hash.update(b"\x00")
+
+    return hash.hexdigest()
+
+
+def get_default_cache_directory() -> str:
+    # ref: https://github.com/mandiant/capa/issues/1212#issuecomment-1361259813
+    #
+    # Linux:   $XDG_CACHE_HOME/capa/
+    # Windows: %LOCALAPPDATA%\flare\capa\cache
+    # MacOS:   ~/Library/Caches/capa
+
+    # ref: https://stackoverflow.com/a/8220141/87207
+    if sys.platform == "linux" or sys.platform == "linux2":
+        directory = os.environ.get("XDG_CACHE_HOME", os.path.join(os.environ["HOME"], ".cache", "capa"))
+    elif sys.platform == "darwin":
+        directory = os.path.join(os.environ["HOME"], "Library", "Caches", "capa")
+    elif sys.platform == "win32":
+        directory = os.path.join(os.environ["LOCALAPPDATA"], "flare", "capa", "cache")
+    else:
+        raise NotImplementedError(f"unsupported platform: {sys.platform}")
+
+    os.makedirs(directory, exist_ok=True)
+
+    return directory
+
+
+def get_cache_path(cache_dir: str, id: CacheIdentifier) -> str:
+    filename = "capa-" + id[:8] + ".cache"
+    return os.path.join(cache_dir, filename)
+
+
+MAGIC = b"capa"
+VERSION = b"\x00\x00\x00\x01"
+
+
+@dataclass
+class RuleCache:
+    id: CacheIdentifier
+    ruleset: capa.rules.RuleSet
+
+    def dump(self):
+        return MAGIC + VERSION + self.id.encode("ascii") + zlib.compress(pickle.dumps(self))
+
+    @staticmethod
+    def load(data):
+        assert data.startswith(MAGIC + VERSION)
+
+        id = data[0x8:0x48].decode("ascii")
+        cache = pickle.loads(zlib.decompress(data[0x48:]))
+
+        assert isinstance(cache, RuleCache)
+        assert cache.id == id
+
+        return cache
+
+
+def get_ruleset_content(ruleset: capa.rules.RuleSet) -> List[bytes]:
+    rule_contents = []
+    for rule in ruleset.rules.values():
+        if rule.is_subscope_rule():
+            continue
+        rule_contents.append(rule.definition.encode("utf-8"))
+    return rule_contents
+
+
+def compute_ruleset_cache_identifier(ruleset: capa.rules.RuleSet) -> CacheIdentifier:
+    rule_contents = get_ruleset_content(ruleset)
+    return compute_cache_identifier(rule_contents)
+
+
+def cache_ruleset(cache_dir: str, ruleset: capa.rules.RuleSet):
+    """
+    cache the given ruleset to disk, using the given cache directory.
+    this can subsequently be reloaded via `load_cached_ruleset`,
+    assuming the capa version and rule content does not change.
+
+    callers should use this function to avoid the performance overhead
+    of validating rules on each run.
+    """
+    id = compute_ruleset_cache_identifier(ruleset)
+    path = get_cache_path(cache_dir, id)
+    if os.path.exists(path):
+        logger.debug("rule set already cached to %s", path)
+        return
+
+    cache = RuleCache(id, ruleset)
+    with open(path, "wb") as f:
+        f.write(cache.dump())
+
+    logger.debug("rule set cached to %s", path)
+    return
+
+
+def load_cached_ruleset(cache_dir: str, rule_contents: List[bytes]) -> Optional[capa.rules.RuleSet]:
+    """
+    load a cached ruleset from disk, using the given cache directory.
+    the raw rule contents are required here to prove that the rules haven't changed
+    and to avoid stale cache entries.
+
+    callers should use this function to avoid the performance overhead
+    of validating rules on each run.
+    """
+    id = compute_cache_identifier(rule_contents)
+    path = get_cache_path(cache_dir, id)
+    if not os.path.exists(path):
+        logger.debug("rule set cache does not exist: %s", path)
+        return None
+
+    logger.debug("loading rule set from cache: %s", path)
+    with open(path, "rb") as f:
+        buf = f.read()
+
+    try:
+        cache = RuleCache.load(buf)
+    except AssertionError:
+        logger.debug("rule set cache is invalid: %s", path)
+        # delete the cache that seems to be invalid.
+        os.remove(path)
+        return None
+    else:
+        return cache.ruleset

capa/version.py

@@ -1,13 +1,5 @@
-__version__ = "4.0.1"
+__version__ = "5.0.0"
 
 
 def get_major_version():
     return int(__version__.partition(".")[0])
-
-
-def get_rules_branch():
-    return f"v{get_major_version()}"
-
-
-def get_rules_checkout_command():
-    return f"$ git clone https://github.com/mandiant/capa-rules.git -b {get_rules_branch()} /local/path/to/rules"

doc/installation.md

@@ -6,13 +6,11 @@ If you simply want to use capa, use the standalone binaries we host on GitHub: h
 
 We use PyInstaller to create these packages.
 
-The capa [README](../README.md#download) also links to nightly builds of standalone binaries from the latest development branch.
-
 ### Linux Standalone installation
 
 The Linux Standalone binary has been built using GLIB 2.26.
-Consequently it works when using GLIB >= 2.26.
-This requirement is satisfied by default in most newer distribution such as Ubuntu >= 18, Debian >= 10, openSUSE >= 15.1 and CentOS >= 8.
+Consequently, it works when using GLIB >= 2.26.
+This requirement is satisfied by default in newer distribution such as Ubuntu >= 18, Debian >= 10, openSUSE >= 15.1 and CentOS >= 8.
 But the binary may not work in older distributions.
 
 ### MacOS Standalone installation
@@ -24,24 +22,27 @@ By default, on MacOS Catalina or greater, Gatekeeper will block execution of the
 ## Method 2: Using capa as a Python library
 To install capa as a Python library use `pip` to fetch the `flare-capa` module.
 
-#### *Note*:
+### 1. Install capa module
+Use `pip` to install the capa module to your local Python environment. This fetches the library code to your computer but does not keep editable source files around for you to hack on. If you'd like to edit the source files, see below. `$ pip install flare-capa`
+
+#### *Note on capa rules and library identification signatures*
 This method is appropriate for integrating capa in an existing project.
-This technique doesn't pull the default rule set, so you should check it out separately from [capa-rules](https://github.com/mandiant/capa-rules/) and pass the directory to the entrypoint using `-r` or set the rules path in the IDA Pro plugin:
+This technique doesn't pull the default rule set. You can obtain rule releases from [capa-rules](https://github.com/mandiant/capa-rules/releases) and pass the directory to the entrypoint using `-r`. In the IDA Pro plugin you need to configure the rules directory path once.
 
 ```console
-$ git clone https://github.com/mandiant/capa-rules.git -b v3 /local/path/to/rules
-$ capa     -r /local/path/to/rules   suspicious.exe
+$ wget https://github.com/mandiant/capa-rules/archive/refs/tags/v4.0.0.zip
+$ unzip v4.0.0.zip
+$ capa -r /path/to/capa-rules suspicious.exe
 ```
 
 This technique also doesn't set up the default library identification [signatures](https://github.com/mandiant/capa/tree/master/sigs). You can pass the signature directory using the `-s` argument.
 For example, to run capa with both a rule path and a signature path:
+```console
+$ capa -s /path/to/capa-sigs suspicious.exe
+```
 
-    capa   -r /path/to/capa-rules   -s /path/to/capa-sigs  suspicious.exe
 Alternatively, see Method 3 below.
 
-### 1. Install capa module
-Use `pip` to install the capa module to your local Python environment. This fetches the library code to your computer but does not keep editable source files around for you to hack on. If you'd like to edit the source files, see below. `$ pip install flare-capa`
-
 ### 2. Use capa
 You can now import the `capa` module from a Python script or use the IDA Pro plugins from the `capa/ida` directory. For more information please see the [usage](usage.md) documentation.
 
@@ -49,18 +50,20 @@ You can now import the `capa` module from a Python script or use the IDA Pro plu
 If you'd like to review and modify the capa source code, you'll need to check it out from GitHub and install it locally. By following these instructions, you'll maintain a local directory of source code that you can modify and run easily. 
 
 ### 1. Check out source code
-Next, clone the capa git repository.
+Clone the capa git repository.
 We use submodules to separate [code](https://github.com/mandiant/capa), [rules](https://github.com/mandiant/capa-rules), and [test data](https://github.com/mandiant/capa-testfiles).
+
 To clone everything use the `--recurse-submodules` option:
-- CAUTION: The capa testfiles repository contains many malware samples. If you pull down everything using this method, you may want to install to a directory that won't trigger your anti-virus software.
+- CAUTION: The capa testfiles repository contains many malware samples. If you pull down everything using this method, you may want to install to a directory that is ignored by your anti-virus software.
 - `$ git clone --recurse-submodules https://github.com/mandiant/capa.git /local/path/to/src` (HTTPS)
 - `$ git clone --recurse-submodules git@github.com:mandiant/capa.git /local/path/to/src` (SSH)
 
-To only get the source code and our provided rules (common), follow these steps:
+To only get the source code and our provided rules (a more common use-case), follow these steps:
 - clone repository
   - `$ git clone https://github.com/mandiant/capa.git /local/path/to/src` (HTTPS)
   - `$ git clone git@github.com:mandiant/capa.git /local/path/to/src` (SSH)
 - `$ cd /local/path/to/src`
+- initialize the rules submodule and pull rules
 - `$ git submodule update --init rules`
 
 ### 2. Install the local source code
@@ -76,8 +79,7 @@ You'll find that the `capa.exe` (Windows) or `capa` (Linux/MacOS) executables in
 
 For development, we recommend to use [venv](https://docs.python.org/3/tutorial/venv.html). It allows you to create a virtual environment: a self-contained directory tree that contains a Python installation for a particular version of Python, plus a number of additional packages. This approach avoids conflicts between the requirements of different applications on your computer. It also ensures that you don't overlook to add a new requirement to `setup.up` using a library already installed on your system.
 
-To create an environment (in the parent directory, to avoid commiting it by accident or messing with the linters), run:
-`$ python3 -m venv ../capa-env`
+To create an environment (in the parent directory, to avoid committing it by accident or messing with the linters), run: `$ python3 -m venv ../capa-env`
 
 To activate `capa-env` in Linux or MacOS, run:
 `$ source ../capa-env/bin/activate`
@@ -90,8 +92,8 @@ For more details about creating and using virtual environments, check out the [v
 ##### Install development dependencies
 
 We use the following tools to ensure consistent code style and formatting:
-  - [black](https://github.com/psf/black) code formatter, with `-l 120`
-  - [isort 5](https://pypi.org/project/isort/) code formatter, with `--profile black --length-sort --line-width 120`
+  - [black](https://github.com/psf/black) code formatter
+  - [isort 5](https://pypi.org/project/isort/) code formatter
   - [dos2unix](https://linux.die.net/man/1/dos2unix) for UNIX-style LF newlines
   - [capafmt](https://github.com/mandiant/capa/blob/master/scripts/capafmt.py) rule formatter
 
@@ -104,7 +106,7 @@ You can run it with the argument `no_tests` to skip the tests and only run the c
 
 ##### Setup hooks [optional]
 
-If you plan to contribute to capa, you may want to setup the hooks.
+If you plan to contribute to capa, you may want to setup the provided hooks.
 Run `scripts/setup-hooks.sh` to set the following hooks up:
 - The `pre-commit` hook runs checks before every `git commit`.
   It runs `scripts/ci.sh no_tests` aborting the commit if there are code style or rule linter offenses you need to fix.
@@ -112,13 +114,17 @@ Run `scripts/setup-hooks.sh` to set the following hooks up:
   It runs `scripts/ci.sh` aborting the push if there are code style or rule linter offenses or if the tests fail.
   This way you can ensure everything is alright before sending a pull request.
 
-You can skip the checks by using the `--no-verify` git option.
+You can skip the checks by using the `-n`/`--no-verify` git option.
 
 ### 3. Compile binary using PyInstaller
-We compile capa standalone binaries using PyInstaller. To reproduce the build process check out the source code as described above and follow these steps.
+We compile capa standalone binaries using PyInstaller. To reproduce the build process check out the source code as described above and follow the following steps.
 
 #### Install PyInstaller:
-`$ pip install pyinstaller` (Python 3)
+`$ pip install pyinstaller`
+
+Or install capa with build dependencies:
+
+`$ pip install -e /local/path/to/src[build]`
 
 #### Run Pyinstaller
 `$ pyinstaller .github/pyinstaller/pyinstaller.spec`

doc/release.md

@@ -3,7 +3,7 @@
 - [ ] Ensure all [milestoned issues/PRs](https://github.com/mandiant/capa/milestones) are addressed, or reassign to a new milestone.
 - [ ] Add the `dont merge` label to all PRs that are close to be ready to merge (or merge them if they are ready) in [capa](https://github.com/mandiant/capa/pulls) and [capa-rules](https://github.com/mandiant/capa-rules/pulls).
 - [ ] Ensure the [CI workflow succeeds in master](https://github.com/mandiant/capa/actions/workflows/tests.yml?query=branch%3Amaster).
-- [ ] Ensure that `python scripts/lint.py rules/ --thorough` succeeds (only `missing examples`  offenses are allowed in the nursery).
+- [ ] Ensure that `python scripts/lint.py rules/ --thorough` succeeds (only `missing examples` offenses are allowed in the nursery). You can [manually trigger a thorough lint](https://github.com/mandiant/capa-rules/actions/workflows/tests.yml) in CI via the "Run workflow" option. 
 - [ ] Review changes
   - capa https://github.com/mandiant/capa/compare/\<last-release\>...master
   - capa-rules https://github.com/mandiant/capa-rules/compare/\<last-release>\...master
@@ -37,13 +37,10 @@
 - [ ] Update [capa/version.py](https://github.com/mandiant/capa/blob/master/capa/version.py)
 - [ ] Create a PR with the updated [CHANGELOG.md](https://github.com/mandiant/capa/blob/master/CHANGELOG.md) and [capa/version.py](https://github.com/mandiant/capa/blob/master/capa/version.py). Copy this checklist in the PR description.
 - [ ] After PR review, merge the PR and [create the release in GH](https://github.com/mandiant/capa/releases/new) using text from the [CHANGELOG.md](https://github.com/mandiant/capa/blob/master/CHANGELOG.md).
-- [ ] Verify GH actions [upload artifacts](https://github.com/mandiant/capa/releases), [publish to PyPI](https://pypi.org/project/flare-capa) and [create a tag in capa rules](https://github.com/mandiant/capa-rules/tags) upon completion.
-- [ ] Manually update capa rules major version rule branch
-  ```commandline
-  [capa/rules] $ git pull master
-  [capa/rules] $ git checkout v3  # create if new major version: git checkout -b vX
-  [capa/rules] $ git merge master
-  [capa/rules] $ git push origin v3
-  ```
+- Verify GH actions
+  - [ ] [upload artifacts](https://github.com/mandiant/capa/releases)
+  - [ ] [publish to PyPI](https://pypi.org/project/flare-capa)
+  - [ ] [create tag in capa rules](https://github.com/mandiant/capa-rules/tags)
+  - [ ] [create release in capa rules](https://github.com/mandiant/capa-rules/releases)
 - [ ] [Spread the word](https://twitter.com)
 - [ ] Update internal service

doc/rules.md

@@ -1,6 +1,5 @@
 ### rules
 
-
 capa uses a collection of rules to identify capabilities within a program.
 The [github.com/mandiant/capa-rules](https://github.com/mandiant/capa-rules) repository contains hundreds of standard library rules that are distributed with capa.
 
@@ -12,8 +11,8 @@ $ capa suspicious.exe
 
 However, you may want to modify the rules for a variety of reasons:
 
-  - develop new rules to find behaviors, and/or
-  - tweak existing rules to reduce false positives, and/or
+  - develop new rules to find behaviors,
+  - tweak existing rules to reduce false positives,
   - collect a private selection of rules not shared publicly.
 
 Or, you may want to use capa as a Python library within another application.
@@ -21,22 +20,18 @@ Or, you may want to use capa as a Python library within another application.
 In these scenarios, you must provide the rule set to capa as a directory on your file system. Do this using the `-r`/`--rules` parameter:
 
 ```console
-$ capa    --rules /local/path/to/rules    suspicious.exe
+$ capa --rules /local/path/to/rules suspicious.exe
 ```
 
-You can collect the standard set of rules in two ways:
+You can download the standard set of rules as ZIP or TGZ archives from the [capa-rules release page](https://github.com/mandiant/capa-rules/releases).
 
-  - [download from the Github releases page](#download-release-archive), or
-  - [clone from Github](#clone-with-git).
-
-Note that you must use match the rules major version with the capa major version,
-i.e., use `v1` rules with `v1` of capa.
+Note that you must use match the rules major version with the capa major version, i.e., use `v1` rules with `v1` of capa.
 This is so that new versions of capa can update rule syntax, such as by adding new fields and logic.
 
 Otherwise, using rules with a mismatched version of capa may lead to errors like:
 
 ```
-$ capa   --rules /path/to/mismatched/rules    suspicious.exe
+$ capa --rules /path/to/mismatched/rules suspicious.exe
 ERROR:lint:invalid rule: injection.yml: invalid rule: unexpected statement: instruction
 ```                
 
@@ -46,27 +41,3 @@ You can check the version of capa you're currently using like this:
 $ capa --version
 capa 3.0.3
 ```
-
-#### download release archive
-
-The releases page is [here](https://github.com/mandiant/capa-rules/tags/).
-Find the most recent release corresponding to your major version of capa and download the ZIP archive.
-Here are some quick links:
-  - v1: [v1](https://github.com/mandiant/capa-rules/releases/tag/v1)
-  - v2: [v2](https://github.com/mandiant/capa-rules/releases/tag/v2)
-  - v3: [v3](https://github.com/mandiant/capa-rules/releases/tag/v3)
-
-#### clone with git
-
-To fetch with git, clone the appropriate branch like this:
-
-```console
-$ git clone https://github.com/mandiant/capa-rules.git -b v3 /local/path/to/rules
-```
-
-Note that the branch name (`v3` in the example above) must match the major version of capa you're using.
-
-  - [v1](https://github.com/mandiant/capa-rules/tree/v1): `v1`
-  - [v2](https://github.com/mandiant/capa-rules/tree/v2): `v2`
-  - [v3](https://github.com/mandiant/capa-rules/tree/v3): `v3`
-

scripts/bulk-process.py

@@ -153,7 +153,6 @@ def main(argv=None):
 
         try:
             rules = capa.main.get_rules(args.rules)
-            rules = capa.rules.RuleSet(rules)
             logger.info("successfully loaded %s rules", len(rules))
         except (IOError, capa.rules.InvalidRule, capa.rules.InvalidRuleSet) as e:
             logger.error("%s", str(e))
@@ -161,12 +160,12 @@ def main(argv=None):
 
         try:
             sig_paths = capa.main.get_signatures(args.signatures)
-        except (IOError) as e:
+        except IOError as e:
             logger.error("%s", str(e))
             return -1
 
         samples = []
-        for (base, directories, files) in os.walk(args.input):
+        for base, directories, files in os.walk(args.input):
             for file in files:
                 samples.append(os.path.join(base, file))
 

scripts/cache-ruleset.py

@@ -0,0 +1,67 @@
+"""
+Create a cache of the given rules.
+This is only really intended to be used by CI to pre-cache rulesets 
+that will be distributed within PyInstaller binaries.
+
+Usage:
+
+   $ python scripts/cache-ruleset.py rules/ /path/to/cache/directory
+
+Copyright (C) 2023 Mandiant, Inc. All Rights Reserved.
+Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+You may obtain a copy of the License at: [package root]/LICENSE.txt
+Unless required by applicable law or agreed to in writing, software distributed under the License
+ is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and limitations under the License.
+"""
+import os
+import sys
+import time
+import logging
+import argparse
+
+import capa.main
+import capa.rules
+import capa.engine
+import capa.helpers
+import capa.rules.cache
+import capa.features.insn
+
+logger = logging.getLogger("cache-ruleset")
+
+
+def main(argv=None):
+    if argv is None:
+        argv = sys.argv[1:]
+
+    parser = argparse.ArgumentParser(description="Cache ruleset.")
+    capa.main.install_common_args(parser)
+    parser.add_argument("rules", type=str, action="append", help="Path to rules")
+    parser.add_argument("cache", type=str, help="Path to cache directory")
+    args = parser.parse_args(args=argv)
+    capa.main.handle_common_args(args)
+
+    if args.debug:
+        logging.getLogger("capa").setLevel(logging.DEBUG)
+    else:
+        logging.getLogger("capa").setLevel(logging.ERROR)
+
+    try:
+        os.makedirs(args.cache, exist_ok=True)
+        rules = capa.main.get_rules(args.rules, cache_dir=args.cache)
+        logger.info("successfully loaded %s rules", len(rules))
+    except (IOError, capa.rules.InvalidRule, capa.rules.InvalidRuleSet) as e:
+        logger.error("%s", str(e))
+        return -1
+
+    content = capa.rules.cache.get_ruleset_content(rules)
+    id = capa.rules.cache.compute_cache_identifier(content)
+    path = capa.rules.cache.get_cache_path(args.cache, id)
+
+    assert os.path.exists(path)
+    logger.info("cached to: %s", path)
+
+
+if __name__ == "__main__":
+    sys.exit(main())

scripts/capa2yara.py

@@ -64,7 +64,6 @@ unsupported = ["characteristic", "mnemonic", "offset", "subscope", "Range"]
 
 # collect all converted rules to be able to check if we have needed sub rules for match:
 converted_rules = []
-count_incomplete = 0
 
 default_tags = "CAPA "
 
@@ -129,8 +128,7 @@ def convert_capa_number_to_yara_bytes(number):
 
 
 def convert_rule_name(rule_name):
-
-    # yara rule names: "Identifiers must follow the same lexical conventions of the C programming language, they can contain any alphanumeric character and the underscore character, but the first character cannot be a digit. Rule identifiers are case sensitive and cannot exceed 128 characters." so we replace any non-alpanum with _
+    # yara rule names: "Identifiers must follow the same lexical conventions of the C programming language, they can contain any alphanumeric character and the underscore character, but the first character cannot be a digit. Rule identifiers are case sensitive and cannot exceed 128 characters." so we replace any non-alphanum with _
     rule_name = re.sub(r"\W", "_", rule_name)
     rule_name = "capa_" + rule_name
 
@@ -152,7 +150,6 @@ def convert_description(statement):
 
 
 def convert_rule(rule, rulename, cround, depth):
-
     depth += 1
     logger.info("recursion depth: " + str(depth))
 
@@ -284,12 +281,12 @@ def convert_rule(rule, rulename, cround, depth):
             # change capas /xxx/i to yaras /xxx/ nocase, count will be used later to decide appending 'nocase'
             regex, count = re.subn(r"/i$", "/", regex)
 
-            # remove / in the begining and end
+            # remove / in the beginning and end
             regex = regex[1:-1]
 
             # all .* in the regexes of capa look like they should be maximum 100 chars so take 1000 to speed up rules and prevent yara warnings on poor performance
             regex = regex.replace(".*", ".{,1000}")
-            # strange: capa accepts regexes with unsescaped / like - string: /com/exe4j/runtime/exe4jcontroller/i in capa-rules/compiler/exe4j/compiled-with-exe4j.yml, needs a fix for yara:
+            # strange: capa accepts regexes with unescaped / like - string: /com/exe4j/runtime/exe4jcontroller/i in capa-rules/compiler/exe4j/compiled-with-exe4j.yml, needs a fix for yara:
             # would assume that get_value_str() gives the raw string
             regex = re.sub(r"(?<!\\)/", r"\/", regex)
 
@@ -297,7 +294,7 @@ def convert_rule(rule, rulename, cround, depth):
             # /reg(|.exe)/ => /reg(.exe)?/
             regex = re.sub(r"\(\|([^\)]+)\)", r"(\1)?", regex)
 
-            # change begining of line to null byte, e.g. /^open => /\x00open (not word boundary because we're not looking for the begining of a word in a text but usually a function name if there's ^ in a capa rule)
+            # change beginning of line to null byte, e.g. /^open => /\x00open (not word boundary because we're not looking for the beginning of a word in a text but usually a function name if there's ^ in a capa rule)
             regex = re.sub(r"^\^", r"\\x00", regex)
 
             # regex = re.sub(r"^\^", r"\\b", regex)
@@ -378,7 +375,7 @@ def convert_rule(rule, rulename, cround, depth):
 
             if s_type == "Some":
                 cmin = kid.count
-                logger.info("Some type with mininum: " + str(cmin))
+                logger.info("Some type with minimum: " + str(cmin))
 
                 if not cmin:
                     logger.info("this is optional: which means, we can just ignore it")
@@ -483,7 +480,7 @@ def convert_rule(rule, rulename, cround, depth):
 
     elif statement == "Some":
         cmin = rule.count
-        logger.info("Some type with mininum at2: " + str(cmin))
+        logger.info("Some type with minimum at2: " + str(cmin))
 
         if not cmin:
             logger.info("this is optional: which means, we can just ignore it")
@@ -516,7 +513,6 @@ def output_yar(yara):
 
 
 def output_unsupported_capa_rules(yaml, capa_rulename, url, reason):
-
     if reason != "NOLOG":
         if capa_rulename not in unsupported_capa_rules_list:
             logger.info("unsupported: " + capa_rulename + " - reason: " + reason + " - url: " + url)
@@ -537,9 +533,9 @@ def output_unsupported_capa_rules(yaml, capa_rulename, url, reason):
             unsupported_capa_rules_names.write(url.encode("utf-8") + b"\n")
 
 
-def convert_rules(rules, namespaces, cround):
+def convert_rules(rules, namespaces, cround, make_priv):
+    count_incomplete = 0
     for rule in rules.rules.values():
-
         rule_name = convert_rule_name(rule.name)
 
         if rule.is_subscope_rule():
@@ -579,7 +575,6 @@ def convert_rules(rules, namespaces, cround):
                 output_unsupported_capa_rules(rule.to_yaml(), rule.name, url, yara_condition)
             logger.info("Unknown feature at5: " + rule.name)
         else:
-
             yara_meta = ""
             metas = rule.meta
             rule_tags = ""
@@ -623,7 +618,7 @@ def convert_rules(rules, namespaces, cround):
                             value = re.sub(r"^([0-9a-f]{20,64}):0x[0-9a-f]{1,10}$", r"\1", value, flags=re.IGNORECASE)
 
                             # examples in capa can contain the same hash several times with different offset, so check if it's already there:
-                            # (keeping the offset might be interessting for some but breaks yara-ci for checking of the final rules
+                            # (keeping the offset might be interesting for some but breaks yara-ci for checking of the final rules
                             if value not in seen_hashes:
                                 yara_meta += "\t" + meta_name + ' = "' + value + '"\n'
                                 seen_hashes.append(value)
@@ -652,7 +647,6 @@ def convert_rules(rules, namespaces, cround):
                     if meta_name and meta_value:
                         yara_meta += "\t" + meta_name + ' = "' + meta_value + '"\n'
 
-            rule_name_bonus = ""
             if rule_comment:
                 yara_meta += '\tcomment = "' + rule_comment + '"\n'
             yara_meta += '\tdate = "' + today + '"\n'
@@ -662,7 +656,6 @@ def convert_rules(rules, namespaces, cround):
             # check if there's some beef in condition:
             tmp_yc = re.sub(r"(and|or|not)", "", yara_condition)
             if re.search(r"\w", tmp_yc):
-
                 yara = ""
                 if make_priv:
                     yara = "private "
@@ -679,12 +672,13 @@ def convert_rules(rules, namespaces, cround):
                 # TODO: now the rule is finished and could be automatically checked with the capa-testfile(s) named in meta (doing it for all of them using yara-ci upload at the moment)
                 output_yar(yara)
                 converted_rules.append(rule_name)
-                global count_incomplete
                 count_incomplete += incomplete
             else:
                 output_unsupported_capa_rules(rule.to_yaml(), rule.name, url, yara_condition)
                 pass
 
+    return count_incomplete
+
 
 def main(argv=None):
     if argv is None:
@@ -696,7 +690,6 @@ def main(argv=None):
     capa.main.install_common_args(parser, wanted={"tag"})
 
     args = parser.parse_args(args=argv)
-    global make_priv
     make_priv = args.private
 
     if args.verbose:
@@ -710,9 +703,8 @@ def main(argv=None):
     logging.getLogger("capa2yara").setLevel(level)
 
     try:
-        rules = capa.main.get_rules([args.rules], disable_progress=True)
-        namespaces = capa.rules.index_rules_by_namespace(list(rules))
-        rules = capa.rules.RuleSet(rules)
+        rules = capa.main.get_rules([args.rules])
+        namespaces = capa.rules.index_rules_by_namespace(list(rules.rules.values()))
         logger.info("successfully loaded %s rules (including subscope rules which will be ignored)", len(rules))
         if args.tag:
             rules = rules.filter_rules_by_meta(args.tag)
@@ -745,14 +737,15 @@ def main(argv=None):
     # do several rounds of converting rules because some rules for match: might not be converted in the 1st run
     num_rules = 9999999
     cround = 0
+    count_incomplete = 0
     while num_rules != len(converted_rules) or cround < min_rounds:
         cround += 1
         logger.info("doing convert_rules(), round: " + str(cround))
         num_rules = len(converted_rules)
-        convert_rules(rules, namespaces, cround)
+        count_incomplete += convert_rules(rules, namespaces, cround, make_priv)
 
     # one last round to collect all unconverted rules
-    convert_rules(rules, namespaces, 9000)
+    count_incomplete += convert_rules(rules, namespaces, 9000, make_priv)
 
     stats = "\n// converted rules              : " + str(len(converted_rules))
     stats += "\n//   among those are incomplete : " + str(count_incomplete)

scripts/capa_as_library.py

@@ -16,7 +16,7 @@ import capa.features.freeze.features as frzf
 from capa.engine import *
 
 
-# == Render ddictionary helpers
+# == Render dictionary helpers
 def render_meta(doc: rd.ResultDocument, result):
     result["md5"] = doc.meta.sample.md5
     result["sha1"] = doc.meta.sample.sha1
@@ -106,7 +106,7 @@ def render_attack(doc, result):
 
     for tactic, techniques in sorted(tactics.items()):
         inner_rows = []
-        for (technique, subtechnique, id) in sorted(techniques):
+        for technique, subtechnique, id in sorted(techniques):
             if subtechnique is None:
                 inner_rows.append("%s %s" % (technique, id))
             else:
@@ -140,7 +140,7 @@ def render_mbc(doc, result):
 
     for objective, behaviors in sorted(objectives.items()):
         inner_rows = []
-        for (behavior, method, id) in sorted(behaviors):
+        for behavior, method, id in sorted(behaviors):
             if method is None:
                 inner_rows.append("%s [%s]" % (behavior, id))
             else:
@@ -161,7 +161,7 @@ def render_dictionary(doc: rd.ResultDocument) -> Dict[str, Any]:
 # ==== render dictionary helpers
 def capa_details(rules_path, file_path, output_format="dictionary"):
     # load rules from disk
-    rules = capa.rules.RuleSet(capa.main.get_rules([rules_path], disable_progress=True))
+    rules = capa.main.get_rules([rules_path])
 
     # extract features and find capabilities
     extractor = capa.main.get_extractor(file_path, "auto", capa.main.BACKEND_VIV, [], False, disable_progress=True)
@@ -172,7 +172,7 @@ def capa_details(rules_path, file_path, output_format="dictionary"):
     meta["analysis"].update(counts)
     meta["analysis"]["layout"] = capa.main.compute_layout(rules, extractor, capabilities)
 
-    capa_output = False
+    capa_output: Any = False
     if output_format == "dictionary":
         # ...as python dictionary, simplified as textable but in dictionary
         doc = rd.ResultDocument.from_capa(meta, rules, capabilities)

scripts/ci.sh

@@ -11,12 +11,12 @@
 # Use a console with emojis support for a better experience
 # Use venv to ensure that `python` calls the correct python version
 
-# Stash uncommited changes
+# Stash uncommitted changes
 MSG="pre-push-$(date +%s)";
 git stash push -kum "$MSG" &>/dev/null ;
 STASH_LIST=$(git stash list);
 if [[ "$STASH_LIST" == *"$MSG"* ]]; then
-  echo "Uncommited changes stashed with message '$MSG', if you abort before they are restored run \`git stash pop\`";
+  echo "Uncommitted changes stashed with message '$MSG', if you abort before they are restored run \`git stash pop\`";
 fi
 
 restore_stashed() {

scripts/detect-elf-os.py

@@ -28,7 +28,7 @@ def main(argv=None):
     if capa.helpers.is_runtime_ida():
         from capa.ida.helpers import IDAIO
 
-        f: BinaryIO = IDAIO()
+        f: BinaryIO = IDAIO()  # type: ignore
 
     else:
         if argv is None:

scripts/import-to-ida.py

@@ -31,7 +31,7 @@ See the License for the specific language governing permissions and limitations
 import json
 import logging
 
-import idautils
+import ida_nalt
 import ida_funcs
 import ida_kernwin
 
@@ -51,7 +51,11 @@ def append_func_cmt(va, cmt, repeatable=False):
     if cmt in existing:
         return
 
-    new = existing + "\n" + cmt
+    if len(existing) > 0:
+        new = existing + "\n" + cmt
+    else:
+        new = cmt
+
     ida_funcs.set_func_cmt(func, new, repeatable)
 
 
@@ -73,7 +77,7 @@ def main():
     #
     # see: https://github.com/idapython/bin/issues/11
     a = doc["meta"]["sample"]["md5"].lower()
-    b = idautils.GetInputFileMD5().decode("ascii").lower().rstrip("\x00")
+    b = ida_nalt.retrieve_input_file_md5().lower()
     if not a.startswith(b):
         logger.error("sample mismatch")
         return -2

scripts/lint.py

@@ -248,7 +248,7 @@ class InvalidAttckOrMbcTechnique(Lint):
     """
 
     def __init__(self):
-        super(InvalidAttckOrMbcTechnique, self).__init__()
+        super().__init__()
 
         try:
             with open(f"{os.path.dirname(__file__)}/linter-data.json", "rb") as fd:
@@ -307,11 +307,7 @@ def get_sample_capabilities(ctx: Context, path: Path) -> Set[str]:
     elif nice_path.endswith(capa.helpers.EXTENSIONS_SHELLCODE_64):
         format_ = "sc64"
     else:
-        format_ = "auto"
-        if not nice_path.endswith(capa.helpers.EXTENSIONS_ELF):
-            dnfile_extractor = capa.features.extractors.dnfile_.DnfileFeatureExtractor(nice_path)
-            if dnfile_extractor.is_dotnet_file():
-                format_ = FORMAT_DOTNET
+        format_ = capa.main.get_auto_format(nice_path)
 
     logger.debug("analyzing sample: %s", nice_path)
     extractor = capa.main.get_extractor(nice_path, format_, "", DEFAULT_SIGNATURES, False, disable_progress=True)
@@ -894,7 +890,6 @@ def redirecting_print_to_tqdm():
     old_print = print
 
     def new_print(*args, **kwargs):
-
         # If tqdm.tqdm.write raises error, use builtin print
         try:
             tqdm.tqdm.write(*args, **kwargs)
@@ -902,11 +897,15 @@ def redirecting_print_to_tqdm():
             old_print(*args, **kwargs)
 
     try:
-        # Globaly replace print with new_print
-        inspect.builtins.print = new_print
+        # Globally replace print with new_print.
+        # Verified this works manually on Python 3.11:
+        #     >>> import inspect
+        #     >>> inspect.builtins
+        #     <module 'builtins' (built-in)>
+        inspect.builtins.print = new_print  # type: ignore
         yield
     finally:
-        inspect.builtins.print = old_print
+        inspect.builtins.print = old_print  # type: ignore
 
 
 def lint(ctx: Context):
@@ -917,12 +916,11 @@ def lint(ctx: Context):
     """
     ret = {}
 
-    with tqdm.contrib.logging.tqdm_logging_redirect(ctx.rules.rules.items(), unit="rule") as pbar:
+    source_rules = [rule for rule in ctx.rules.rules.values() if not rule.is_subscope_rule()]
+    with tqdm.contrib.logging.tqdm_logging_redirect(source_rules, unit="rule") as pbar:
         with redirecting_print_to_tqdm():
-            for name, rule in pbar:
-                if rule.is_subscope_rule():
-                    continue
-
+            for rule in pbar:
+                name = rule.name
                 pbar.set_description(width("linting rule: %s" % (name), 48))
                 ret[name] = lint_rule(ctx, rule)
 
@@ -998,10 +996,8 @@ def main(argv=None):
     time0 = time.time()
 
     try:
-        rules = capa.main.get_rules(args.rules, disable_progress=True)
-        rule_count = len(rules)
-        rules = capa.rules.RuleSet(rules)
-        logger.info("successfully loaded %s rules", rule_count)
+        rules = capa.main.get_rules(args.rules)
+        logger.info("successfully loaded %s rules", rules.source_rule_count)
         if args.tag:
             rules = rules.filter_rules_by_meta(args.tag)
             logger.debug("selected %s rules", len(rules))

scripts/profile-time.py

@@ -88,14 +88,14 @@ def main(argv=None):
 
     try:
         with capa.main.timing("load rules"):
-            rules = capa.rules.RuleSet(capa.main.get_rules(args.rules, disable_progress=True))
-    except (IOError) as e:
+            rules = capa.main.get_rules(args.rules)
+    except IOError as e:
         logger.error("%s", str(e))
         return -1
 
     try:
         sig_paths = capa.main.get_signatures(args.signatures)
-    except (IOError) as e:
+    except IOError as e:
         logger.error("%s", str(e))
         return -1
 
@@ -120,7 +120,7 @@ def main(argv=None):
     logger.debug("perf: find capabilities: avg: %0.2fs" % (sum(samples) / float(args.repeat) / float(args.number)))
     logger.debug("perf: find capabilities: max: %0.2fs" % (max(samples) / float(args.number)))
 
-    for (counter, count) in capa.perf.counters.most_common():
+    for counter, count in capa.perf.counters.most_common():
         logger.debug("perf: counter: {:}: {:,}".format(counter, count))
 
     print(

scripts/setup-linter-dependencies.py

@@ -70,7 +70,7 @@ class MitreExtractor:
         self._memory_store = MemoryStore(stix_data=stix_json["objects"])
 
     @staticmethod
-    def _remove_deprecated_objetcs(stix_objects) -> List[AttackPattern]:
+    def _remove_deprecated_objects(stix_objects) -> List[AttackPattern]:
         """Remove any revoked or deprecated objects from queries made to the data source."""
         return list(
             filter(
@@ -82,7 +82,7 @@ class MitreExtractor:
     def _get_tactics(self) -> List[Dict]:
         """Get tactics IDs from Mitre matrix."""
         # Only one matrix for enterprise att&ck framework
-        matrix = self._remove_deprecated_objetcs(
+        matrix = self._remove_deprecated_objects(
             self._memory_store.query(
                 [
                     Filter("type", "=", "x-mitre-matrix"),
@@ -93,7 +93,7 @@ class MitreExtractor:
 
     def _get_techniques_from_tactic(self, tactic: str) -> List[AttackPattern]:
         """Get techniques and sub techniques from a Mitre tactic (kill_chain_phases->phase_name)"""
-        techniques = self._remove_deprecated_objetcs(
+        techniques = self._remove_deprecated_objects(
             self._memory_store.query(
                 [
                     Filter("type", "=", "attack-pattern"),
@@ -107,7 +107,7 @@ class MitreExtractor:
     def _get_parent_technique_from_subtechnique(self, technique: AttackPattern) -> AttackPattern:
         """Get parent technique of a sub technique using the technique ID TXXXX.YYY"""
         sub_id = technique["external_references"][0]["external_id"].split(".")[0]
-        parent_technique = self._remove_deprecated_objetcs(
+        parent_technique = self._remove_deprecated_objects(
             self._memory_store.query(
                 [
                     Filter("type", "=", "attack-pattern"),
@@ -125,7 +125,10 @@ class MitreExtractor:
         data: Dict[str, Dict[str, str]] = {}
         for tactic in self._get_tactics():
             data[tactic["name"]] = {}
-            for technique in self._get_techniques_from_tactic(tactic["x_mitre_shortname"]):
+            for technique in sorted(
+                self._get_techniques_from_tactic(tactic["x_mitre_shortname"]),
+                key=lambda x: x["external_references"][0]["external_id"],
+            ):
                 tid = technique["external_references"][0]["external_id"]
                 technique_name = technique["name"].split("::")[0]
                 if technique["x_mitre_is_subtechnique"]:
@@ -151,7 +154,7 @@ class MbcExtractor(MitreExtractor):
 
     def _get_tactics(self) -> List[Dict]:
         """Override _get_tactics to edit the tactic name for Micro-objective"""
-        tactics = super(MbcExtractor, self)._get_tactics()
+        tactics = super()._get_tactics()
         # We don't want the Micro-objective string inside objective names
         for tactic in tactics:
             tactic["name"] = tactic["name"].replace(" Micro-objective", "")

scripts/show-capabilities-by-function.py

@@ -142,7 +142,6 @@ def main(argv=None):
 
     try:
         rules = capa.main.get_rules(args.rules)
-        rules = capa.rules.RuleSet(rules)
         logger.info("successfully loaded %s rules", len(rules))
         if args.tag:
             rules = rules.filter_rules_by_meta(args.tag)
@@ -153,16 +152,16 @@ def main(argv=None):
 
     try:
         sig_paths = capa.main.get_signatures(args.signatures)
-    except (IOError) as e:
+    except IOError as e:
         logger.error("%s", str(e))
         return -1
 
     if (args.format == "freeze") or (args.format == "auto" and capa.features.freeze.is_freeze(taste)):
-        format = "freeze"
+        format_ = "freeze"
         with open(args.sample, "rb") as f:
             extractor = capa.features.freeze.load(f.read())
     else:
-        format = args.format
+        format_ = args.format
         should_save_workspace = os.environ.get("CAPA_SAVE_WORKSPACE") not in ("0", "no", "NO", "n", None)
 
         try:

scripts/show-features.py

@@ -79,6 +79,7 @@ import capa.exceptions
 import capa.render.verbose as v
 import capa.features.common
 import capa.features.freeze
+import capa.features.address
 import capa.features.extractors.base_extractor
 from capa.helpers import log_unsupported_runtime_error
 
@@ -108,7 +109,7 @@ def main(argv=None):
 
     try:
         sig_paths = capa.main.get_signatures(args.signatures)
-    except (IOError) as e:
+    except IOError as e:
         logger.error("%s", str(e))
         return -1
 
@@ -135,7 +136,7 @@ def main(argv=None):
         for feature, addr in extractor.extract_file_features():
             print("file: %s: %s" % (format_address(addr), feature))
 
-    function_handles = extractor.get_functions()
+    function_handles = tuple(extractor.get_functions())
 
     if args.function:
         if args.format == "freeze":
@@ -172,7 +173,7 @@ def ida_main():
             print("file: %s: %s" % (format_address(addr), feature))
         return
 
-    function_handles = extractor.get_functions()
+    function_handles = tuple(extractor.get_functions())
 
     if function:
         function_handles = tuple(filter(lambda fh: fh.inner.start_ea == function, function_handles))

setup.cfg

@@ -19,3 +19,10 @@ test = pytest
 ignore = E203, E302, E402, E501, E712, E722, E731, W291, W503
 max-line-length = 180
 statistics = True
+
+
+[pylint.FORMAT]
+max-line-length = 180
+
+[pylint]
+disable = missing-docstring,invalid-name,import-outside-toplevel,redefined-outer-name,consider-using-f-string

setup.py

@@ -11,24 +11,23 @@ import os
 import setuptools
 
 requirements = [
-    "tqdm==4.64.0",
+    "tqdm==4.64.1",
     "pyyaml==6.0",
-    "tabulate==0.8.9",
+    "tabulate==0.9.0",
     "colorama==0.4.5",
-    "termcolor==1.1.0",
-    "wcwidth==0.2.5",
+    "termcolor==2.2.0",
+    "wcwidth==0.2.6",
     "ida-settings==2.1.0",
-    "viv-utils[flirt]==0.7.5",
+    "viv-utils[flirt]==0.7.7",
     "halo==0.0.31",
-    "networkx==2.5.1",
+    "networkx==2.5.1",  # newer versions no longer support py3.7.
     "ruamel.yaml==0.17.21",
     "vivisect==1.0.8",
-    "smda==1.8.4",
     "pefile==2022.5.30",
-    "pyelftools==0.28",
-    "dnfile==0.11.0",
-    "dncil==1.0.1",
-    "pydantic==1.9.1",
+    "pyelftools==0.29",
+    "dnfile==0.13.0",
+    "dncil==1.0.2",
+    "pydantic==1.10.4",
 ]
 
 # this sets __version__
@@ -69,28 +68,28 @@ setuptools.setup(
     install_requires=requirements,
     extras_require={
         "dev": [
-            "pytest==7.1.2",
+            "pytest==7.1.3",
             "pytest-sugar==0.9.4",
             "pytest-instafail==0.4.2",
-            "pytest-cov==3.0.0",
-            "pycodestyle==2.9.1",
-            "black==22.6.0",
-            "isort==5.10.1",
-            "mypy==0.971",
-            "psutil==5.9.1",
+            "pytest-cov==4.0.0",
+            "pycodestyle==2.10.0",
+            "black==23.1.0",
+            "isort==5.11.4",
+            "mypy==0.991",
+            "psutil==5.9.2",
             "stix2==3.0.1",
             "requests==2.28.0",
             # type stubs for mypy
             "types-backports==0.1.3",
             "types-colorama==0.4.15",
             "types-PyYAML==6.0.8",
-            "types-tabulate==0.8.9",
+            "types-tabulate==0.9.0.0",
             "types-termcolor==1.1.4",
             "types-psutil==5.8.23",
             "types_requests==2.28.1",
         ],
         "build": [
-            "pyinstaller==5.3",
+            "pyinstaller==5.7.0",
         ],
     },
     zip_safe=False,

tests/fixtures.py

@@ -36,6 +36,7 @@ from capa.features.common import (
     Arch,
     Format,
     Feature,
+    FeatureAccess,
 )
 from capa.features.address import Address
 from capa.features.extractors.base_extractor import BBHandle, InsnHandle, FunctionHandle
@@ -117,21 +118,9 @@ def fixup_viv(path, extractor):
     if "3b13b" in path:
         # vivisect only recognizes calling thunk function at 0x10001573
         extractor.vw.makeFunction(0x10006860)
-
-
-@lru_cache()
-def get_smda_extractor(path):
-    from smda.SmdaConfig import SmdaConfig
-    from smda.Disassembler import Disassembler
-
-    import capa.features.extractors.smda.extractor
-
-    config = SmdaConfig()
-    config.STORE_BUFFER = True
-    disasm = Disassembler(config)
-    report = disasm.disassembleFile(path)
-
-    return capa.features.extractors.smda.extractor.SmdaFeatureExtractor(report, path)
+    if "294b8d" in path:
+        # see vivisect/#561
+        extractor.vw.makeFunction(0x404970)
 
 
 @lru_cache(maxsize=1)
@@ -277,8 +266,22 @@ def get_data_path_by_name(name):
         return os.path.join(DNFILE_TESTFILES, "hello-world", "hello-world.exe")
     elif name.startswith("_1c444"):
         return os.path.join(CD, "data", "dotnet", "1c444ebeba24dcba8628b7dfe5fec7c6.exe_")
+    elif name.startswith("_387f15"):
+        return os.path.join(
+            CD, "data", "dotnet", "387f15043f0198fd3a637b0758c2b6dde9ead795c3ed70803426fc355731b173.dll_"
+        )
     elif name.startswith("_692f"):
         return os.path.join(CD, "data", "dotnet", "692f7fd6d198e804d6af98eb9e390d61.exe_")
+    elif name.startswith("_0953c"):
+        return os.path.join(CD, "data", "0953cc3b77ed2974b09e3a00708f88de931d681e2d0cb64afbaf714610beabe6.exe_")
+    elif name.startswith("_039a6"):
+        return os.path.join(CD, "data", "039a6336d0802a2255669e6867a5679c7eb83313dbc61fb1c7232147379bd304.exe_")
+    elif name.startswith("b5f052"):
+        return os.path.join(CD, "data", "b5f0524e69b3a3cf636c7ac366ca57bf5e3a8fdc8a9f01caf196c611a7918a87.elf_")
+    elif name.startswith("bf7a9c"):
+        return os.path.join(CD, "data", "bf7a9c8bdfa6d47e01ad2b056264acc3fd90cf43fe0ed8deec93ab46b47d76cb.elf_")
+    elif name.startswith("294b8d"):
+        return os.path.join(CD, "data", "294b8db1f2702b60fb2e42fdc50c2cee6a5046112da9a5703a548a4fa50477bc.elf_")
     else:
         raise ValueError("unexpected sample fixture: %s" % name)
 
@@ -360,7 +363,7 @@ def get_function(extractor, fva: int) -> FunctionHandle:
 
 def get_function_by_token(extractor, token: int) -> FunctionHandle:
     for fh in extractor.get_functions():
-        if fh.address.token.value == token:
+        if fh.address == token:
             return fh
     raise ValueError("function not found by token")
 
@@ -368,7 +371,7 @@ def get_function_by_token(extractor, token: int) -> FunctionHandle:
 def get_basic_block(extractor, fh: FunctionHandle, va: int) -> BBHandle:
     for bbh in extractor.get_basic_blocks(fh):
         if isinstance(extractor, DnfileFeatureExtractor):
-            addr = bbh.inner.offset
+            addr = bbh.inner.instructions[0].offset
         else:
             addr = bbh.address
         if addr == va:
@@ -629,6 +632,8 @@ FEATURE_PRESENCE_TESTS = sorted(
         ("mimikatz", "function=0x40105D", capa.features.common.String("ACR  > "), True),
         ("mimikatz", "function=0x40105D", capa.features.common.String("nope"), False),
         ("773290...", "function=0x140001140", capa.features.common.String(r"%s:\\OfficePackagesForWDAG"), True),
+        # overlapping string, see #1271
+        ("294b8d...", "function=0x404970,bb=0x404970,insn=0x40499F", capa.features.common.String("\r\n\x00:ht"), False),
         # insn/regex
         ("pma16-01", "function=0x4021B0", capa.features.common.Regex("HTTP/1.0"), True),
         ("pma16-01", "function=0x402F40", capa.features.common.Regex("www.practicalmalwareanalysis.com"), True),
@@ -684,14 +689,22 @@ FEATURE_PRESENCE_TESTS = sorted(
         # os & format & arch
         ("pma16-01", "file", OS(OS_WINDOWS), True),
         ("pma16-01", "file", OS(OS_LINUX), False),
+        ("mimikatz", "file", OS(OS_WINDOWS), True),
         ("pma16-01", "function=0x404356", OS(OS_WINDOWS), True),
         ("pma16-01", "function=0x404356,bb=0x4043B9", OS(OS_WINDOWS), True),
+        ("mimikatz", "function=0x40105D", OS(OS_WINDOWS), True),
         ("pma16-01", "file", Arch(ARCH_I386), True),
         ("pma16-01", "file", Arch(ARCH_AMD64), False),
+        ("mimikatz", "file", Arch(ARCH_I386), True),
         ("pma16-01", "function=0x404356", Arch(ARCH_I386), True),
         ("pma16-01", "function=0x404356,bb=0x4043B9", Arch(ARCH_I386), True),
+        ("mimikatz", "function=0x40105D", Arch(ARCH_I386), True),
         ("pma16-01", "file", Format(FORMAT_PE), True),
         ("pma16-01", "file", Format(FORMAT_ELF), False),
+        ("mimikatz", "file", Format(FORMAT_PE), True),
+        # format is also a global feature
+        ("pma16-01", "function=0x404356", Format(FORMAT_PE), True),
+        ("mimikatz", "function=0x456BB9", Format(FORMAT_PE), True),
         # elf support
         ("7351f.elf", "file", OS(OS_LINUX), True),
         ("7351f.elf", "file", OS(OS_WINDOWS), False),
@@ -718,18 +731,19 @@ FEATURE_PRESENCE_TESTS_DOTNET = sorted(
         ("mixed-mode-64", "file", capa.features.common.Characteristic("mixed mode"), True),
         ("hello-world", "file", capa.features.common.Characteristic("mixed mode"), False),
         ("b9f5b", "file", OS(OS_ANY), True),
+        ("b9f5b", "file", Format(FORMAT_PE), True),
         ("b9f5b", "file", Format(FORMAT_DOTNET), True),
         ("hello-world", "file", capa.features.file.FunctionName("HelloWorld::Main"), True),
-        ("hello-world", "file", capa.features.file.FunctionName("HelloWorld::.ctor"), True),
-        ("hello-world", "file", capa.features.file.FunctionName("HelloWorld::.cctor"), False),
+        ("hello-world", "file", capa.features.file.FunctionName("HelloWorld::ctor"), True),
+        ("hello-world", "file", capa.features.file.FunctionName("HelloWorld::cctor"), False),
         ("hello-world", "file", capa.features.common.String("Hello World!"), True),
         ("hello-world", "file", capa.features.common.Class("HelloWorld"), True),
         ("hello-world", "file", capa.features.common.Class("System.Console"), True),
         ("hello-world", "file", capa.features.common.Namespace("System.Diagnostics"), True),
         ("hello-world", "function=0x250", capa.features.common.String("Hello World!"), True),
-        ("hello-world", "function=0x250, bb=0x250, insn=0x252", capa.features.common.String("Hello World!"), True),
-        ("hello-world", "function=0x250, bb=0x250, insn=0x257", capa.features.common.Class("System.Console"), True),
-        ("hello-world", "function=0x250, bb=0x250, insn=0x257", capa.features.common.Namespace("System"), True),
+        ("hello-world", "function=0x250, bb=0x251, insn=0x252", capa.features.common.String("Hello World!"), True),
+        ("hello-world", "function=0x250, bb=0x251, insn=0x257", capa.features.common.Class("System.Console"), True),
+        ("hello-world", "function=0x250, bb=0x251, insn=0x257", capa.features.common.Namespace("System"), True),
         ("hello-world", "function=0x250", capa.features.insn.API("System.Console::WriteLine"), True),
         ("hello-world", "file", capa.features.file.Import("System.Console::WriteLine"), True),
         ("_1c444", "file", capa.features.common.String(r"SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall"), True),
@@ -740,11 +754,28 @@ FEATURE_PRESENCE_TESTS_DOTNET = sorted(
         ("_1c444", "function=0x1F68", capa.features.insn.API("GetWindowDC"), True),
         ("_1c444", "function=0x1F68", capa.features.insn.API("user32.GetWindowDC"), True),
         ("_1c444", "function=0x1F68", capa.features.insn.Number(0xCC0020), True),
+        ("_1c444", "token=0x600001D", capa.features.common.Characteristic("calls to"), True),
+        ("_1c444", "token=0x6000018", capa.features.common.Characteristic("calls to"), False),
+        ("_1c444", "token=0x600001D", capa.features.common.Characteristic("calls from"), True),
+        ("_1c444", "token=0x600000F", capa.features.common.Characteristic("calls from"), False),
+        ("_1c444", "token=0x600001D", capa.features.common.Characteristic("loop"), True),
+        ("_1c444", "token=0x0600008C", capa.features.common.Characteristic("loop"), False),
         ("_1c444", "function=0x1F68", capa.features.insn.Number(0x0), True),
         ("_1c444", "function=0x1F68", capa.features.insn.Number(0x1), False),
+        ("_692f", "token=0x6000004", capa.features.insn.API("System.Linq.Enumerable::First"), True),  # generic method
+        (
+            "_692f",
+            "token=0x6000004",
+            capa.features.insn.Property("System.Linq.Enumerable::First"),
+            False,
+        ),  # generic method
+        ("_692f", "token=0x6000004", capa.features.common.Namespace("System.Linq"), True),  # generic method
+        ("_692f", "token=0x6000004", capa.features.common.Class("System.Linq.Enumerable"), True),  # generic method
+        ("_1c444", "token=0x6000020", capa.features.common.Namespace("Reqss"), True),  # ldftn
+        ("_1c444", "token=0x6000020", capa.features.common.Class("Reqss.Reqss"), True),  # ldftn
         (
             "_1c444",
-            "function=0x1F59, bb=0x1F59, insn=0x1F5B",
+            "function=0x1F59, bb=0x1F5A, insn=0x1F5B",
             capa.features.common.Characteristic("unmanaged call"),
             True,
         ),
@@ -753,11 +784,166 @@ FEATURE_PRESENCE_TESTS_DOTNET = sorted(
         ("_1c444", "token=0x6000088", capa.features.common.Characteristic("unmanaged call"), False),
         (
             "_1c444",
-            "function=0x1F68, bb=0x1F68, insn=0x1FF9",
+            "function=0x1F68, bb=0x1F74, insn=0x1FF9",
             capa.features.insn.API("System.Drawing.Image::FromHbitmap"),
             True,
         ),
-        ("_1c444", "function=0x1F68, bb=0x1F68, insn=0x1FF9", capa.features.insn.API("FromHbitmap"), False),
+        ("_1c444", "function=0x1F68, bb=0x1F74, insn=0x1FF9", capa.features.insn.API("FromHbitmap"), False),
+        (
+            "_1c444",
+            "token=0x600002B",
+            capa.features.insn.Property("System.IO.FileInfo::Length", access=FeatureAccess.READ),
+            True,
+        ),  # MemberRef property access
+        (
+            "_1c444",
+            "token=0x600002B",
+            capa.features.insn.Property("System.IO.FileInfo::Length"),
+            True,
+        ),  # MemberRef property access
+        (
+            "_1c444",
+            "token=0x6000081",
+            capa.features.insn.API("System.Diagnostics.Process::Start"),
+            True,
+        ),  # MemberRef property access
+        (
+            "_1c444",
+            "token=0x6000081",
+            capa.features.insn.Property(
+                "System.Diagnostics.ProcessStartInfo::UseShellExecute", access=FeatureAccess.WRITE
+            ),  # MemberRef property access
+            True,
+        ),
+        (
+            "_1c444",
+            "token=0x6000081",
+            capa.features.insn.Property(
+                "System.Diagnostics.ProcessStartInfo::WorkingDirectory", access=FeatureAccess.WRITE
+            ),  # MemberRef property access
+            True,
+        ),
+        (
+            "_1c444",
+            "token=0x6000081",
+            capa.features.insn.Property(
+                "System.Diagnostics.ProcessStartInfo::FileName", access=FeatureAccess.WRITE
+            ),  # MemberRef property access
+            True,
+        ),
+        (
+            "_1c444",
+            "token=0x6000087",
+            capa.features.insn.Property(
+                "Sockets.MySocket::reConnectionDelay", access=FeatureAccess.WRITE
+            ),  # Field property access
+            True,
+        ),
+        (
+            "_1c444",
+            "token=0x600008A",
+            capa.features.insn.Property(
+                "Sockets.MySocket::isConnected", access=FeatureAccess.WRITE
+            ),  # Field property access
+            True,
+        ),
+        (
+            "_1c444",
+            "token=0x600008A",
+            capa.features.common.Class("Sockets.MySocket"),  # Field property access
+            True,
+        ),
+        (
+            "_1c444",
+            "token=0x600008A",
+            capa.features.common.Namespace("Sockets"),  # Field property access
+            True,
+        ),
+        (
+            "_1c444",
+            "token=0x600008A",
+            capa.features.insn.Property(
+                "Sockets.MySocket::onConnected", access=FeatureAccess.READ
+            ),  # Field property access
+            True,
+        ),
+        (
+            "_0953c",
+            "token=0x6000004",
+            capa.features.insn.Property(
+                "System.Diagnostics.Debugger::IsAttached", access=FeatureAccess.READ
+            ),  # MemberRef property access
+            True,
+        ),
+        (
+            "_0953c",
+            "token=0x6000004",
+            capa.features.common.Class("System.Diagnostics.Debugger"),  # MemberRef property access
+            True,
+        ),
+        (
+            "_0953c",
+            "token=0x6000004",
+            capa.features.common.Namespace("System.Diagnostics"),  # MemberRef property access
+            True,
+        ),
+        (
+            "_692f",
+            "token=0x6000006",
+            capa.features.insn.Property(
+                "System.Management.Automation.PowerShell::Streams", access=FeatureAccess.READ
+            ),  # MemberRef property access
+            False,
+        ),
+        (
+            "_387f15",
+            "token=0x600009E",
+            capa.features.insn.Property(
+                "Modulo.IqQzcRDvSTulAhyLtZHqyeYGgaXGbuLwhxUKXYmhtnOmgpnPJDTSIPhYPpnE::geoplugin_countryCode",
+                access=FeatureAccess.READ,
+            ),  # MethodDef property access
+            True,
+        ),
+        (
+            "_387f15",
+            "token=0x600009E",
+            capa.features.common.Class(
+                "Modulo.IqQzcRDvSTulAhyLtZHqyeYGgaXGbuLwhxUKXYmhtnOmgpnPJDTSIPhYPpnE"
+            ),  # MethodDef property access
+            True,
+        ),
+        (
+            "_387f15",
+            "token=0x600009E",
+            capa.features.common.Namespace("Modulo"),  # MethodDef property access
+            True,
+        ),
+        (
+            "_039a6",
+            "token=0x6000007",
+            capa.features.insn.API("System.Reflection.Assembly::Load"),
+            True,
+        ),
+        (
+            "_039a6",
+            "token=0x600001D",
+            capa.features.insn.Property("StagelessHollow.Arac::Marka", access=FeatureAccess.READ),  # MethodDef method
+            True,
+        ),
+        (
+            "_039a6",
+            "token=0x600001C",
+            capa.features.insn.Property("StagelessHollow.Arac::Marka", access=FeatureAccess.READ),  # MethodDef method
+            False,
+        ),
+        (
+            "_039a6",
+            "token=0x6000023",
+            capa.features.insn.Property(
+                "System.Runtime.CompilerServices.AsyncTaskMethodBuilder::Task", access=FeatureAccess.READ
+            ),  # MemberRef method
+            False,
+        ),
     ],
     # order tests by (file, item)
     # so that our LRU cache is most effective.
@@ -770,6 +956,7 @@ FEATURE_PRESENCE_TESTS_IDA = [
     ("mimikatz", "file", capa.features.file.Import("cabinet.FCIAddFile"), True),
 ]
 
+
 FEATURE_COUNT_TESTS = [
     ("mimikatz", "function=0x40E5C2", capa.features.basicblock.BasicBlock(), 7),
     ("mimikatz", "function=0x4702FD", capa.features.common.Characteristic("calls from"), 0),
@@ -778,8 +965,12 @@ FEATURE_COUNT_TESTS = [
     ("mimikatz", "function=0x40B1F1", capa.features.common.Characteristic("calls to"), 3),
 ]
 
-
-FEATURE_COUNT_TESTS_DOTNET = []  # type: ignore
+FEATURE_COUNT_TESTS_DOTNET = [
+    ("_1c444", "token=0x06000072", capa.features.basicblock.BasicBlock(), 1),
+    ("_1c444", "token=0x0600008C", capa.features.basicblock.BasicBlock(), 10),
+    ("_1c444", "token=0x600001D", capa.features.common.Characteristic("calls to"), 1),
+    ("_1c444", "token=0x600001D", capa.features.common.Characteristic("calls from"), 9),
+]
 
 
 def do_test_feature_presence(get_extractor, sample, scope, feature, expected):
@@ -904,3 +1095,13 @@ def _1c444_dotnetfile_extractor():
 @pytest.fixture
 def _692f_dotnetfile_extractor():
     return get_dnfile_extractor(get_data_path_by_name("_692f"))
+
+
+@pytest.fixture
+def _0953c_dotnetfile_extractor():
+    return get_dnfile_extractor(get_data_path_by_name("_0953c"))
+
+
+@pytest.fixture
+def _039a6_dotnetfile_extractor():
+    return get_dnfile_extractor(get_data_path_by_name("_039a6"))