Files
capa/tests/test_engine.py
2023-04-04 19:10:40 +05:30

142 lines
6.8 KiB
Python

# 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 capa.features.address
from capa.engine import *
from capa.features import *
from capa.features.insn import *
ADDR1 = capa.features.address.AbsoluteVirtualAddress(0x401001)
ADDR2 = capa.features.address.AbsoluteVirtualAddress(0x401002)
ADDR3 = capa.features.address.AbsoluteVirtualAddress(0x401003)
ADDR4 = capa.features.address.AbsoluteVirtualAddress(0x401004)
def test_number():
assert Number(1).evaluate({Number(0): {ADDR1}}) is False
assert Number(1).evaluate({Number(1): {ADDR1}}) is True
assert Number(1).evaluate({Number(2): {ADDR1, ADDR2}}) is False
def test_and():
assert And([Number(1)]).evaluate({Number(0): {ADDR1}}) is False
assert And([Number(1)]).evaluate({Number(1): {ADDR1}}) is True
assert And([Number(1), Number(2)]).evaluate({Number(0): {ADDR1}}) is False
assert And([Number(1), Number(2)]).evaluate({Number(1): {ADDR1}}) is False
assert And([Number(1), Number(2)]).evaluate({Number(2): {ADDR1}}) is False
assert And([Number(1), Number(2)]).evaluate({Number(1): {ADDR1}, Number(2): {ADDR2}}) is True
def test_or():
assert Or([Number(1)]).evaluate({Number(0): {ADDR1}}) is False
assert Or([Number(1)]).evaluate({Number(1): {ADDR1}}) is True
assert Or([Number(1), Number(2)]).evaluate({Number(0): {ADDR1}}) is False
assert Or([Number(1), Number(2)]).evaluate({Number(1): {ADDR1}}) is True
assert Or([Number(1), Number(2)]).evaluate({Number(2): {ADDR1}}) is True
assert Or([Number(1), Number(2)]).evaluate({Number(1): {ADDR1}, Number(2): {ADDR2}}) is True
def test_not():
assert Not(Number(1)).evaluate({Number(0): {ADDR1}}) is True
assert Not(Number(1)).evaluate({Number(1): {ADDR1}}) is False
def test_some():
assert Some(0, [Number(1)]).evaluate({Number(0): {ADDR1}}) is True
assert Some(1, [Number(1)]).evaluate({Number(0): {ADDR1}}) is False
assert Some(2, [Number(1), Number(2), Number(3)]).evaluate({Number(0): {ADDR1}}) is False
assert Some(2, [Number(1), Number(2), Number(3)]).evaluate({Number(0): {ADDR1}, Number(1): {ADDR1}}) is False
assert (
Some(2, [Number(1), Number(2), Number(3)]).evaluate(
{Number(0): {ADDR1}, Number(1): {ADDR1}, Number(2): {ADDR1}}
)
is True
)
assert (
Some(2, [Number(1), Number(2), Number(3)]).evaluate(
{Number(0): {ADDR1}, Number(1): {ADDR1}, Number(2): {ADDR1}, Number(3): {ADDR1}}
)
is True
)
assert (
Some(2, [Number(1), Number(2), Number(3)]).evaluate(
{Number(0): {ADDR1}, Number(1): {ADDR1}, Number(2): {ADDR1}, Number(3): {ADDR1}, Number(4): {ADDR1}}
)
is True
)
def test_complex():
assert True is Or(
[And([Number(1), Number(2)]), Or([Number(3), Some(2, [Number(4), Number(5), Number(6)])])]
).evaluate({Number(5): {ADDR1}, Number(6): {ADDR1}, Number(7): {ADDR1}, Number(8): {ADDR1}})
assert False is Or([And([Number(1), Number(2)]), Or([Number(3), Some(2, [Number(4), Number(5)])])]).evaluate(
{Number(5): {ADDR1}, Number(6): {ADDR1}, Number(7): {ADDR1}, Number(8): {ADDR1}}
)
def test_range():
# unbounded range, but no matching feature
# since the lower bound is zero, and there are zero matches, ok
assert Range(Number(1)).evaluate({Number(2): {}}) is True
# unbounded range with matching feature should always match
assert Range(Number(1)).evaluate({Number(1): {}}) is True
assert Range(Number(1)).evaluate({Number(1): {ADDR1}}) is True
# unbounded max
assert Range(Number(1), min=1).evaluate({Number(1): {ADDR1}}) is True
assert Range(Number(1), min=2).evaluate({Number(1): {ADDR1}}) is False
assert Range(Number(1), min=2).evaluate({Number(1): {ADDR1, ADDR2}}) is True
# unbounded min
assert Range(Number(1), max=0).evaluate({Number(1): {ADDR1}}) is False
assert Range(Number(1), max=1).evaluate({Number(1): {ADDR1}}) is True
assert Range(Number(1), max=2).evaluate({Number(1): {ADDR1}}) is True
assert Range(Number(1), max=2).evaluate({Number(1): {ADDR1, ADDR2}}) is True
assert Range(Number(1), max=2).evaluate({Number(1): {ADDR1, ADDR2, ADDR3}}) is False
# we can do an exact match by setting min==max
assert Range(Number(1), min=1, max=1).evaluate({Number(1): {}}) is False
assert Range(Number(1), min=1, max=1).evaluate({Number(1): {ADDR1}}) is True
assert Range(Number(1), min=1, max=1).evaluate({Number(1): {ADDR1, ADDR2}}) is False
# bounded range
assert Range(Number(1), min=1, max=3).evaluate({Number(1): {}}) is False
assert Range(Number(1), min=1, max=3).evaluate({Number(1): {ADDR1}}) is True
assert Range(Number(1), min=1, max=3).evaluate({Number(1): {ADDR1, ADDR2}}) is True
assert Range(Number(1), min=1, max=3).evaluate({Number(1): {ADDR1, ADDR2, ADDR3}}) is True
assert Range(Number(1), min=1, max=3).evaluate({Number(1): {ADDR1, ADDR2, ADDR3, ADDR4}}) is False
def test_short_circuit():
assert Or([Number(1), Number(2)]).evaluate({Number(1): {ADDR1}}) is True
# with short circuiting, only the children up until the first satisfied child are captured.
assert len(Or([Number(1), Number(2)]).evaluate({Number(1): {ADDR1}}, short_circuit=True).children) == 1
assert len(Or([Number(1), Number(2)]).evaluate({Number(1): {ADDR1}}, short_circuit=False).children) == 2
def test_eval_order():
# base cases.
assert Or([Number(1), Number(2)]).evaluate({Number(1): {ADDR1}}) is True
assert Or([Number(1), Number(2)]).evaluate({Number(2): {ADDR1}}) is True
# with short circuiting, only the children up until the first satisfied child are captured.
assert len(Or([Number(1), Number(2)]).evaluate({Number(1): {ADDR1}}).children) == 1
assert len(Or([Number(1), Number(2)]).evaluate({Number(2): {ADDR1}}).children) == 2
assert len(Or([Number(1), Number(2)]).evaluate({Number(1): {ADDR1}, Number(2): {ADDR1}}).children) == 1
# and its guaranteed that children are evaluated in order.
assert Or([Number(1), Number(2)]).evaluate({Number(1): {ADDR1}}).children[0].statement == Number(1)
assert Or([Number(1), Number(2)]).evaluate({Number(1): {ADDR1}}).children[0].statement != Number(2)
assert Or([Number(1), Number(2)]).evaluate({Number(2): {ADDR1}}).children[1].statement == Number(2)
assert Or([Number(1), Number(2)]).evaluate({Number(2): {ADDR1}}).children[1].statement != Number(1)