lief-iat-reconstruction/patch.py

74 lines
3.2 KiB
Python

from utils import hex_address_to_memory_representation
import lief
def patch_direct_adress_call(pe: lief.PE.Binary, rva: int, instruction_offset: int):
# We can manually patch the instruction here: FF 15 08 10 00 01 represents `call [0x01001080]`
new_value = hex_address_to_memory_representation(
hex(rva + pe.imagebase),
pe.abstract.header.is_32,
pe.abstract.header.endianness == lief.Header.ENDIANNESS.LITTLE,
)
pe.patch_address(instruction_offset, [0xFF, 0x15] + new_value, lief.Binary.VA_TYPES.RVA)
def patch_direct_adress_jump(pe: lief.PE.Binary, rva: int, instruction_offset: int):
# We can manually patch the instruction here: FF 15 08 10 00 01 represents `call [0x01001080]`
new_value = hex_address_to_memory_representation(
hex(rva + pe.imagebase),
pe.abstract.header.is_32,
pe.abstract.header.endianness == lief.Header.ENDIANNESS.LITTLE,
)
pe.patch_address(instruction_offset, [0xFF, 0x25] + new_value, lief.Binary.VA_TYPES.RVA)
def patch_instr_to_new_IAT_entry(pe: lief.PE.Binary, call: dict[str, str], rva: int):
base = pe.imagebase
instruction_offset = int(call["adress"], 16) - base
memview = pe.get_content_from_virtual_address(instruction_offset, 2)
if [memview[0], memview[1]] == [0xFF, 0x15]:
patch_direct_adress_call(pe, rva, instruction_offset)
elif [memview[0], memview[1]] == [0xFF, 0x25]:
patch_direct_adress_jump(pe, rva, instruction_offset)
def patch_addr_found_in_mem(pe: lief.PE.Binary, rva: int, old_addr: str):
is_32 = pe.abstract.header.is_32
little_endian = pe.abstract.header.endianness == lief.Header.ENDIANNESS.LITTLE
# scan memory for reference to old addr
old_addr_mem_repr = hex_address_to_memory_representation(
old_addr,
is_32,
pe.abstract.header.endianness == lief.Header.ENDIANNESS.LITTLE,
)
new_addr = hex_address_to_memory_representation(
hex(rva + pe.imagebase),
is_32,
little_endian,
)
adresses_to_patch = []
for section in pe.sections:
for i in range(len(section.content)):
found = True
for j in range(len(old_addr_mem_repr)):
if i + j >= len(section.content) or section.content[i + j] != old_addr_mem_repr[j]:
found = False
break
if found:
old_addr_ref = hex_address_to_memory_representation(
hex(
section.virtual_address + i + pe.imagebase,
),
is_32,
little_endian,
)
for section in pe.sections:
for k in range(len(section.content)):
foundxref = True
for L in range(len(old_addr_ref)):
if k + L < len(section.content) and section.content[k + L] != old_addr_ref[L]:
foundxref = False
break
if foundxref:
adresses_to_patch.append(section.virtual_address + k)
for addr in adresses_to_patch:
pe.patch_address(addr, new_addr, lief.Binary.VA_TYPES.RVA)