Files
capa/tests/fixtures.py
2020-08-14 12:22:39 -06:00

407 lines
18 KiB
Python

# Copyright (C) 2020 FireEye, 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 os.path
import collections
import pytest
import capa.main
import capa.features.file
import capa.features.insn
import capa.features.basicblock
from capa.features import ARCH_X32, ARCH_X64
try:
from functools import lru_cache
except ImportError:
from backports.functools_lru_cache import lru_cache
CD = os.path.dirname(__file__)
@lru_cache()
def get_viv_extractor(path):
import capa.features.extractors.viv
if "raw32" in path:
vw = capa.main.get_workspace(path, "sc32", should_save=False)
elif "raw64" in path:
vw = capa.main.get_workspace(path, "sc64", should_save=False)
else:
vw = capa.main.get_workspace(path, "auto", should_save=True)
return capa.features.extractors.viv.VivisectFeatureExtractor(vw, path)
@lru_cache()
def extract_file_features(extractor):
features = collections.defaultdict(set)
for feature, va in extractor.extract_file_features():
features[feature].add(va)
return features
@lru_cache()
def extract_function_features(extractor, f):
features = collections.defaultdict(set)
for bb in extractor.get_basic_blocks(f):
for insn in extractor.get_instructions(f, bb):
for feature, va in extractor.extract_insn_features(f, bb, insn):
features[feature].add(va)
for feature, va in extractor.extract_basic_block_features(f, bb):
features[feature].add(va)
for feature, va in extractor.extract_function_features(f):
features[feature].add(va)
return features
@lru_cache()
def extract_basic_block_features(extractor, f, bb):
features = collections.defaultdict(set)
for insn in extractor.get_instructions(f, bb):
for feature, va in extractor.extract_insn_features(f, bb, insn):
features[feature].add(va)
for feature, va in extractor.extract_basic_block_features(f, bb):
features[feature].add(va)
return features
def get_data_path_by_name(name):
if name == "mimikatz":
return os.path.join(CD, "data", "mimikatz.exe_")
elif name == "kernel32":
return os.path.join(CD, "data", "kernel32.dll_")
elif name == "kernel32-64":
return os.path.join(CD, "data", "kernel32-64.dll_")
elif name == "pma12-04":
return os.path.join(CD, "data", "Practical Malware Analysis Lab 12-04.exe_")
elif name == "pma21-01":
return os.path.join(CD, "data", "Practical Malware Analysis Lab 21-01.exe_")
elif name == "al-khaser x86":
return os.path.join(CD, "data", "al-khaser_x86.exe_")
elif name.startswith("39c05"):
return os.path.join(CD, "data", "39c05b15e9834ac93f206bc114d0a00c357c888db567ba8f5345da0529cbed41.dll_")
elif name.startswith("499c2"):
return os.path.join(CD, "data", "499c2a85f6e8142c3f48d4251c9c7cd6.raw32")
elif name.startswith("9324d"):
return os.path.join(CD, "data", "9324d1a8ae37a36ae560c37448c9705a.exe_")
elif name.startswith("a1982"):
return os.path.join(CD, "data", "a198216798ca38f280dc413f8c57f2c2.exe_")
elif name.startswith("a933a"):
return os.path.join(CD, "data", "a933a1a402775cfa94b6bee0963f4b46.dll_")
elif name.startswith("bfb9b"):
return os.path.join(CD, "data", "bfb9b5391a13d0afd787e87ab90f14f5.dll_")
elif name.startswith("c9188"):
return os.path.join(CD, "data", "c91887d861d9bd4a5872249b641bc9f9.exe_")
else:
raise ValueError("unexpected sample fixture")
@pytest.fixture
def sample(request):
return get_data_path_by_name(request.param)
def get_function(extractor, fva):
for f in extractor.get_functions():
if f.__int__() == fva:
return f
raise ValueError("function not found")
def get_basic_block(extractor, f, va):
for bb in extractor.get_basic_blocks(f):
if bb.__int__() == va:
return bb
raise ValueError("basic block not found")
@pytest.fixture
def scope(request):
if request.param == "file":
def inner(extractor):
return extract_file_features(extractor)
inner.__name__ = request.param
return inner
elif "bb=" in request.param:
# like `function=0x401000,bb=0x40100A`
fspec, _, bbspec = request.param.partition(",")
fva = int(fspec.partition("=")[2], 0x10)
bbva = int(bbspec.partition("=")[2], 0x10)
def inner(extractor):
f = get_function(extractor, fva)
bb = get_basic_block(extractor, f, bbva)
return extract_basic_block_features(extractor, f, bb)
inner.__name__ = request.param
return inner
elif request.param.startswith("function"):
# like `function=0x401000`
va = int(request.param.partition("=")[2], 0x10)
def inner(extractor):
f = get_function(extractor, va)
return extract_function_features(extractor, f)
inner.__name__ = request.param
return inner
else:
raise ValueError("unexpected scope fixture")
def make_test_id(values):
return "-".join(map(str, values))
def parametrize(params, values, **kwargs):
"""
extend `pytest.mark.parametrize` to pretty-print features.
by default, it renders objects as an opaque value.
ref: https://docs.pytest.org/en/2.9.0/example/parametrize.html#different-options-for-test-ids
rendered ID might look something like:
mimikatz-function=0x403BAC-api(CryptDestroyKey)-True
"""
ids = list(map(make_test_id, values))
return pytest.mark.parametrize(params, values, ids=ids, **kwargs)
FEATURE_PRESENCE_TESTS = [
# file/characteristic("embedded pe")
("pma12-04", "file", capa.features.Characteristic("embedded pe"), True),
# file/string
("mimikatz", "file", capa.features.String("SCardControl"), True),
("mimikatz", "file", capa.features.String("SCardTransmit"), True),
("mimikatz", "file", capa.features.String("ACR > "), True),
("mimikatz", "file", capa.features.String("nope"), False),
# file/sections
("mimikatz", "file", capa.features.file.Section(".rsrc"), True),
("mimikatz", "file", capa.features.file.Section(".text"), True),
("mimikatz", "file", capa.features.file.Section(".nope"), False),
# file/exports
("kernel32", "file", capa.features.file.Export("BaseThreadInitThunk"), True),
("kernel32", "file", capa.features.file.Export("lstrlenW"), True),
("kernel32", "file", capa.features.file.Export("nope"), False),
# file/imports
("mimikatz", "file", capa.features.file.Import("advapi32.CryptSetHashParam"), True),
("mimikatz", "file", capa.features.file.Import("CryptSetHashParam"), True),
("mimikatz", "file", capa.features.file.Import("kernel32.IsWow64Process"), True),
("mimikatz", "file", capa.features.file.Import("msvcrt.exit"), True),
("mimikatz", "file", capa.features.file.Import("cabinet.#11"), True),
("mimikatz", "file", capa.features.file.Import("#11"), False),
("mimikatz", "file", capa.features.file.Import("#nope"), False),
("mimikatz", "file", capa.features.file.Import("nope"), False),
# function/characteristic(loop)
("mimikatz", "function=0x401517", capa.features.Characteristic("loop"), True),
("mimikatz", "function=0x401000", capa.features.Characteristic("loop"), False),
# bb/characteristic(tight loop)
("mimikatz", "function=0x402EC4", capa.features.Characteristic("tight loop"), True),
("mimikatz", "function=0x401000", capa.features.Characteristic("tight loop"), False),
# bb/characteristic(stack string)
("mimikatz", "function=0x4556E5", capa.features.Characteristic("stack string"), True),
("mimikatz", "function=0x401000", capa.features.Characteristic("stack string"), False),
# bb/characteristic(tight loop)
("mimikatz", "function=0x402EC4,bb=0x402F8E", capa.features.Characteristic("tight loop"), True),
("mimikatz", "function=0x401000,bb=0x401000", capa.features.Characteristic("tight loop"), False),
# insn/mnemonic
("mimikatz", "function=0x40105D", capa.features.insn.Mnemonic("push"), True),
("mimikatz", "function=0x40105D", capa.features.insn.Mnemonic("movzx"), True),
("mimikatz", "function=0x40105D", capa.features.insn.Mnemonic("xor"), True),
("mimikatz", "function=0x40105D", capa.features.insn.Mnemonic("in"), False),
("mimikatz", "function=0x40105D", capa.features.insn.Mnemonic("out"), False),
# insn/number
("mimikatz", "function=0x40105D", capa.features.insn.Number(0xFF), True),
("mimikatz", "function=0x40105D", capa.features.insn.Number(0x3136B0), True),
# insn/number: stack adjustments
("mimikatz", "function=0x40105D", capa.features.insn.Number(0xC), False),
("mimikatz", "function=0x40105D", capa.features.insn.Number(0x10), False),
# insn/number: arch flavors
("mimikatz", "function=0x40105D", capa.features.insn.Number(0xFF), True),
("mimikatz", "function=0x40105D", capa.features.insn.Number(0xFF, arch=ARCH_X32), True),
("mimikatz", "function=0x40105D", capa.features.insn.Number(0xFF, arch=ARCH_X64), False),
# insn/offset
("mimikatz", "function=0x40105D", capa.features.insn.Offset(0x0), True),
("mimikatz", "function=0x40105D", capa.features.insn.Offset(0x4), True),
("mimikatz", "function=0x40105D", capa.features.insn.Offset(0xC), True),
# insn/offset: stack references
("mimikatz", "function=0x40105D", capa.features.insn.Offset(0x8), False),
("mimikatz", "function=0x40105D", capa.features.insn.Offset(0x10), False),
# insn/offset: negative
("mimikatz", "function=0x4011FB", capa.features.insn.Offset(-0x1), True),
("mimikatz", "function=0x4011FB", capa.features.insn.Offset(-0x2), True),
# insn/offset: arch flavors
("mimikatz", "function=0x40105D", capa.features.insn.Offset(0x0), True),
("mimikatz", "function=0x40105D", capa.features.insn.Offset(0x0, arch=ARCH_X32), True),
("mimikatz", "function=0x40105D", capa.features.insn.Offset(0x0, arch=ARCH_X64), False),
# insn/api
("mimikatz", "function=0x403BAC", capa.features.insn.API("advapi32.CryptAcquireContextW"), True),
("mimikatz", "function=0x403BAC", capa.features.insn.API("advapi32.CryptAcquireContext"), True),
("mimikatz", "function=0x403BAC", capa.features.insn.API("advapi32.CryptGenKey"), True),
("mimikatz", "function=0x403BAC", capa.features.insn.API("advapi32.CryptImportKey"), True),
("mimikatz", "function=0x403BAC", capa.features.insn.API("advapi32.CryptDestroyKey"), True),
("mimikatz", "function=0x403BAC", capa.features.insn.API("CryptAcquireContextW"), True),
("mimikatz", "function=0x403BAC", capa.features.insn.API("CryptAcquireContext"), True),
("mimikatz", "function=0x403BAC", capa.features.insn.API("CryptGenKey"), True),
("mimikatz", "function=0x403BAC", capa.features.insn.API("CryptImportKey"), True),
("mimikatz", "function=0x403BAC", capa.features.insn.API("CryptDestroyKey"), True),
("mimikatz", "function=0x403BAC", capa.features.insn.API("Nope"), False),
("mimikatz", "function=0x403BAC", capa.features.insn.API("advapi32.Nope"), False),
# insn/api: thunk
("mimikatz", "function=0x4556E5", capa.features.insn.API("advapi32.LsaQueryInformationPolicy"), True),
("mimikatz", "function=0x4556E5", capa.features.insn.API("LsaQueryInformationPolicy"), True),
# insn/api: x64
("kernel32-64", "function=0x180001010", capa.features.insn.API("RtlVirtualUnwind"), True,),
("kernel32-64", "function=0x180001010", capa.features.insn.API("RtlVirtualUnwind"), True),
# insn/api: x64 thunk
("kernel32-64", "function=0x1800202B0", capa.features.insn.API("RtlCaptureContext"), True,),
("kernel32-64", "function=0x1800202B0", capa.features.insn.API("RtlCaptureContext"), True),
# insn/api: resolve indirect calls
("c91887...", "function=0x401A77", capa.features.insn.API("kernel32.CreatePipe"), True),
("c91887...", "function=0x401A77", capa.features.insn.API("kernel32.SetHandleInformation"), True),
("c91887...", "function=0x401A77", capa.features.insn.API("kernel32.CloseHandle"), True),
("c91887...", "function=0x401A77", capa.features.insn.API("kernel32.WriteFile"), True),
# insn/string
("mimikatz", "function=0x40105D", capa.features.String("SCardControl"), True),
("mimikatz", "function=0x40105D", capa.features.String("SCardTransmit"), True),
("mimikatz", "function=0x40105D", capa.features.String("ACR > "), True),
("mimikatz", "function=0x40105D", capa.features.String("nope"), False),
# insn/string, pointer to string
("mimikatz", "function=0x44EDEF", capa.features.String("INPUTEVENT"), True),
# insn/bytes
("mimikatz", "function=0x40105D", capa.features.Bytes("SCardControl".encode("utf-16le")), True),
("mimikatz", "function=0x40105D", capa.features.Bytes("SCardTransmit".encode("utf-16le")), True),
("mimikatz", "function=0x40105D", capa.features.Bytes("ACR > ".encode("utf-16le")), True),
("mimikatz", "function=0x40105D", capa.features.Bytes("nope".encode("ascii")), False),
# insn/bytes, pointer to bytes
("mimikatz", "function=0x44EDEF", capa.features.Bytes("INPUTEVENT".encode("utf-16le")), True),
# insn/characteristic(nzxor)
("mimikatz", "function=0x410DFC", capa.features.Characteristic("nzxor"), True),
("mimikatz", "function=0x40105D", capa.features.Characteristic("nzxor"), False),
# insn/characteristic(nzxor): no security cookies
("mimikatz", "function=0x46D534", capa.features.Characteristic("nzxor"), False),
# insn/characteristic(peb access)
("kernel32-64", "function=0x1800017D0", capa.features.Characteristic("peb access"), True),
("mimikatz", "function=0x4556E5", capa.features.Characteristic("peb access"), False),
# insn/characteristic(gs access)
("kernel32-64", "function=0x180001068", capa.features.Characteristic("gs access"), True),
("mimikatz", "function=0x4556E5", capa.features.Characteristic("gs access"), False),
# insn/characteristic(cross section flow)
("a1982...", "function=0x4014D0", capa.features.Characteristic("cross section flow"), True),
# insn/characteristic(cross section flow): imports don't count
("kernel32-64", "function=0x180001068", capa.features.Characteristic("cross section flow"), False),
("mimikatz", "function=0x4556E5", capa.features.Characteristic("cross section flow"), False),
# insn/characteristic(recursive call)
("39c05...", "function=0x10003100", capa.features.Characteristic("recursive call"), True),
("mimikatz", "function=0x4556E5", capa.features.Characteristic("recursive call"), False),
# insn/characteristic(indirect call)
("mimikatz", "function=0x4175FF", capa.features.Characteristic("indirect call"), True),
("mimikatz", "function=0x4556E5", capa.features.Characteristic("indirect call"), False),
# insn/characteristic(calls from)
("mimikatz", "function=0x4556E5", capa.features.Characteristic("calls from"), True),
("mimikatz", "function=0x4702FD", capa.features.Characteristic("calls from"), False),
# function/characteristic(calls to)
("mimikatz", "function=0x40105D", capa.features.Characteristic("calls to"), True),
("mimikatz", "function=0x46C0D2", capa.features.Characteristic("calls to"), False),
]
FEATURE_COUNT_TESTS = [
("mimikatz", "function=0x40E5C2", capa.features.basicblock.BasicBlock(), 7),
("mimikatz", "function=0x40E5C2", capa.features.Characteristic("calls from"), 3),
]
def do_test_feature_presence(get_extractor, sample, scope, feature, expected):
extractor = get_extractor(sample)
features = scope(extractor)
if expected:
msg = "%s should be found in %s" % (str(feature), scope.__name__)
else:
msg = "%s should not be found in %s" % (str(feature), scope.__name__)
assert feature.evaluate(features) == expected, msg
def do_test_feature_count(get_extractor, sample, scope, feature, expected):
extractor = get_extractor(sample)
features = scope(extractor)
msg = "%s should be found %d times in %s" % (str(feature), expected, scope.__name__)
assert len(features[feature]) == expected, msg
def get_extractor(path):
# decide here which extractor to load for tests.
# maybe check which python version we've loaded or if we're in IDA.
extractor = get_viv_extractor(path)
# overload the extractor so that the fixture exposes `extractor.path`
setattr(extractor, "path", path)
return extractor
@pytest.fixture
def mimikatz_extractor():
return get_extractor(get_data_path_by_name("mimikatz"))
@pytest.fixture
def a933a_extractor():
return get_extractor(get_data_path_by_name("a933a..."))
@pytest.fixture
def kernel32_extractor():
return get_extractor(get_data_path_by_name("kernel32"))
@pytest.fixture
def a1982_extractor():
return get_extractor(get_data_path_by_name("a1982..."))
@pytest.fixture
def z9324d_extractor():
return get_extractor(get_data_path_by_name("9324d..."))
@pytest.fixture
def pma12_04_extractor():
return get_extractor(get_data_path_by_name("pma12-04"))
@pytest.fixture
def bfb9b_extractor():
return get_extractor(get_data_path_by_name("bfb9b..."))
@pytest.fixture
def pma21_01_extractor():
return get_extractor(get_data_path_by_name("pma21-01"))
@pytest.fixture
def c9188_extractor():
return get_extractor(get_data_path_by_name("c9188..."))
@pytest.fixture
def z39c05_extractor():
return get_extractor(get_data_path_by_name("39c05..."))
@pytest.fixture
def z499c2_extractor():
return get_extractor(get_data_path_by_name("499c2..."))
@pytest.fixture
def al_khaser_x86_extractor():
return get_extractor(get_data_path_by_name("al-khaser x86"))