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import sys
import os
from pdb import pm
from miasm2.core.cpu import ParseAst
from miasm2.arch.x86.arch import mn_x86, base_expr, variable
from miasm2.core import parse_asm
from miasm2.expression.expression import *
from miasm2.core import asmblock
from elfesteem.strpatchwork import StrPatchwork
from miasm2.analysis.machine import Machine
from miasm2.jitter.csts import *
from miasm2.analysis.dse import DSEEngine
reg_and_id = dict(mn_x86.regs.all_regs_ids_byname)
class DSE_test(object):
"""Inspired from TEST/ARCH/X86
Test the symbolic execution correctly follow generated labels
"""
TXT = '''
main:
SHL EDX, CL
RET
'''
arch_name = "x86_32"
arch_attrib = 32
ret_addr = 0x1337beef
run_addr = 0x0
def __init__(self, jitter_engine):
self.machine = Machine(self.arch_name)
self.myjit = self.machine.jitter(jitter_engine)
self.myjit.init_stack()
self.myjit.jit.log_regs = True
self.myjit.jit.log_mn = True
def init_machine(self):
self.myjit.vm.add_memory_page(self.run_addr, PAGE_READ | PAGE_WRITE, self.assembly)
self.myjit.push_uint32_t(self.ret_addr)
self.myjit.add_breakpoint(self.ret_addr, lambda x:False)
def prepare(self):
self.myjit.cpu.ECX = 4
self.myjit.cpu.EDX = 5
self.dse = DSEEngine(self.machine)
self.dse.attach(self.myjit)
def __call__(self):
self.asm()
self.init_machine()
self.prepare()
self.run()
self.check()
def run(self):
self.myjit.init_run(self.run_addr)
self.myjit.continue_run()
assert(self.myjit.pc == self.ret_addr)
def asm(self):
blocks, symbol_pool = parse_asm.parse_txt(mn_x86, self.arch_attrib, self.TXT,
symbol_pool=self.myjit.ir_arch.symbol_pool)
# fix shellcode addr
symbol_pool.set_offset(symbol_pool.getby_name("main"), 0x0)
s = StrPatchwork()
patches = asmblock.asm_resolve_final(mn_x86, blocks, symbol_pool)
for offset, raw in patches.items():
s[offset] = raw
s = str(s)
self.assembly = s
def check(self):
regs = self.dse.ir_arch.arch.regs
value = self.dse.eval_expr(regs.EDX)
# The expected value should contains '<<', showing it has been in the
# corresponding generated label
expected = ExprOp('<<', regs.EDX,
ExprCompose(regs.ECX[0:8],
ExprInt(0x0, 24)) & ExprInt(0x1F, 32))
assert value == expected
class DSEAttachInBreakpoint(DSE_test):
"""
Test that DSE is "attachable" in a jitter breakpoint
"""
TXT = '''
main:
MOV EAX, 5
ADD EBX, 6
INC EBX
RET
'''
def __init__(self, *args, **kwargs):
super(DSEAttachInBreakpoint, self).__init__(*args, **kwargs)
self._dse = None
self._regs = self.machine.ir().arch.regs
self._testid = ExprId("TEST", self._regs.EBX.size)
def bp_attach(self, jitter):
"""Attach a DSE in the current jitter"""
self.dse = DSEEngine(self.machine)
self.dse.attach(self.myjit)
self.dse.update_state_from_concrete()
self.dse.update_state({
self._regs.EBX: self._testid,
})
# Additionnal call to the exec callback is necessary, as breakpoints are
# honored AFTER exec callback
jitter.exec_cb(jitter)
return True
def prepare(self):
pass
def init_machine(self):
super(DSEAttachInBreakpoint, self).init_machine()
self.myjit.add_breakpoint(5, self.bp_attach) # On ADD EBX, 6
def check(self):
value = self.dse.eval_expr(self._regs.EBX)
# EBX = TEST
# ADD EBX, 6
# INC EBX
# -> EBX_final = TEST + 7
assert value == self._testid + ExprInt(7, self._regs.EBX.size)
if __name__ == "__main__":
[test(*sys.argv[1:])() for test in [
DSE_test,
DSEAttachInBreakpoint,
]]
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