capa/tests/test_scripts.py

# 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 os
import sys
import textwrap
import subprocess

import pytest
from fixtures import *

CD = os.path.dirname(__file__)


def get_script_path(s):
    return os.path.join(CD, "..", "scripts", s)


def get_file_path():
    return os.path.join(CD, "data", "9324d1a8ae37a36ae560c37448c9705a.exe_")


def get_rules_path():
    return os.path.join(CD, "..", "rules")


def get_rule_path():
    return os.path.join(get_rules_path(), "lib", "allocate-memory.yml")


@pytest.mark.parametrize(
    "script,args",
    [
        pytest.param("capa2yara.py", [get_rules_path()]),
        pytest.param("capafmt.py", [get_rule_path()]),
        # not testing lint.py as it runs regularly anyway
        pytest.param("match-function-id.py", [get_file_path()]),
        pytest.param("show-capabilities-by-function.py", [get_file_path()]),
        pytest.param("show-features.py", [get_file_path()]),
        pytest.param("show-features.py", ["-F", "0x407970", get_file_path()]),
        pytest.param("capa_as_library.py", [get_file_path()]),
    ],
)
def test_scripts(script, args):
    script_path = get_script_path(script)
    p = run_program(script_path, args)
    assert p.returncode == 0


def test_bulk_process(tmpdir):
    # create test directory to recursively analyze
    t = tmpdir.mkdir("test")
    with open(os.path.join(CD, "data", "ping_täst.exe_"), "rb") as f:
        t.join("test.exe_").write_binary(f.read())

    p = run_program(get_script_path("bulk-process.py"), [t.dirname])
    assert p.returncode == 0


def run_program(script_path, args):
    args = [sys.executable] + [script_path] + args
    print(f"running: '{args}'")
    return subprocess.run(args, stdout=subprocess.PIPE)


def test_proto_conversion(tmpdir):
    t = tmpdir.mkdir("proto-test")

    json = os.path.join(CD, "data", "rd", "Practical Malware Analysis Lab 01-01.dll_.json")

    p = run_program(get_script_path("proto-from-results.py"), [json])
    assert p.returncode == 0

    pb = os.path.join(t, "pma.pb")
    with open(pb, "wb") as f:
        f.write(p.stdout)

    p = run_program(get_script_path("proto-to-results.py"), [pb])
    assert p.returncode == 0

    assert p.stdout.startswith(b'{\n  "meta": ') or p.stdout.startswith(b'{\r\n  "meta": ')


def run_detect_duplicate_features(rule_dir, rule_path):
    # rule_path = "collection/credit-card/parse-credit-card-information.yml"
    args = [rule_dir, rule_path]
    script_path = get_script_path("detect_duplicate_features.py")
    args = [sys.executable] + [script_path] + args
    print(f"running: '{args}'")
    return subprocess.run(args)


def test_detect_duplicate_features(tmpdir):
    RULESET = {
        "rule_1": textwrap.dedent(
            """
                rule:
                    meta:
                        name: Test Rule 1
                        scope: function
                    features:
                      - or:
                        - string: "sites.ini"
                        - number: 0xEDB88320
            """
        ),
        "rule_2": textwrap.dedent(
            """
                rule:
                    meta:
                        name: Test Rule 2
                        scope: function
                    features:
                      - and:
                        - string: "sites.ini"
                        - number: 8
            """
        ),
        "rule_3": textwrap.dedent(
            """
                rule:
                    meta:
                        name: Test Rule 3
                        scope: function
                    features:
                      - not:
                        - number: 0xEDB88320
            """
        ),
        "rule_4": textwrap.dedent(
            """
                rule:
                    meta:
                        name: Test Rule 4
                        scope: function
                    features:
                      - not:
                        - number: 4
            """
        ),
    }

    rule_dir = tmpdir.mkdir("capa_rule_overlap_test")
    rule_overlaps = [3, 2, 2, 1]
    rule_paths = []
    for rule_name, RULE_CONTENT in RULESET.items():
        rule_file = rule_dir.join("%s.yml" % rule_name)
        rule_file.write(RULE_CONTENT)
        rule_paths.append(rule_file.strpath)
    # tests if number of overlaps for rules in RULESET found are correct.
    for expected_overlaps, rule_path in zip(rule_overlaps, rule_paths):
        overlaps_found = run_detect_duplicate_features(rule_dir.strpath, rule_path)
        assert overlaps_found.returncode == expected_overlaps