refactor: datareuse fixups into project.carrier as transport

This commit is contained in:
Dobin
2024-02-25 18:20:37 +00:00
parent 430f105240
commit 462f23d8cf
6 changed files with 89 additions and 48 deletions
+14 -7
View File
@@ -1,12 +1,12 @@
from typing import Dict, List
import logging
from model.exehost import ExeHost
from model.exehost import DataReuseEntry
logger = logging.getLogger("ExeHost")
logger = logging.getLogger("Carrier")
class IatEntry():
class IatRequest():
def __init__(self, name: str, placeholder: bytes):
self.name: str = name # Function Name, like "VirtualAlloc"
self.placeholder: bytes = placeholder # Random bytes as placeholder
@@ -15,7 +15,8 @@ class IatEntry():
class Carrier():
def __init__(self):
self.iat_requests: List[IatEntry] = []
self.iat_requests: List[IatRequest] = []
self.reusedata_fixups: List[DataReuseEntry] = []
def init(self):
@@ -23,8 +24,14 @@ class Carrier():
def add_iat_request(self, func_name: str, placeholder: bytes):
self.iat_requests.append(IatEntry(func_name, placeholder))
self.iat_requests.append(IatRequest(func_name, placeholder))
def get_all_iat_requests(self) -> List[IatEntry]:
def get_all_iat_requests(self) -> List[IatRequest]:
return self.iat_requests
def set_datareuse_fixups(self, fixups: List[DataReuseEntry]):
self.reusedata_fixups = fixups
def get_all_reusedata_fixups(self) -> List[DataReuseEntry]:
return self.reusedata_fixups
+23 -2
View File
@@ -10,6 +10,28 @@ from peparser.misc import get_physical_address
logger = logging.getLogger("ExeHost")
class RelocEntry():
def __init__(self, rva: int, base_rva: int, type: str):
self.rva: int = rva
self.base_rva: int = base_rva
self.type: str = type
class IatEntry():
def __init__(self, dll_name, func_name, func_addr):
self.dll_name = dll_name
self.func_name = func_name
self.func_addr = func_addr
class DataReuseEntry():
def __init__(self, string_ref: str, register: str, randbytes: bytes):
self.string_ref = string_ref
self.register = register
self.randbytes = randbytes
self.data = b''
self.addr = 0
class ExeHost():
def __init__(self, filepath: FilePath):
@@ -21,7 +43,7 @@ class ExeHost():
self.superpe: SuperPe = None
self.iat = {} # Dict[str, List[Dict[str, str]]]
self.base_relocs = []
self.image_base: int = 0
self.dynamic_base: bool = False
@@ -30,7 +52,6 @@ class ExeHost():
self.code_size: int = 0
self.code_section = None
self.base_relocs = []
self.rwx_section = None
self.ep = None
+4 -5
View File
@@ -19,6 +19,7 @@ def compile(
c_in: FilePath,
asm_out: FilePath,
payload_len: int,
carrier: Carrier,
short_call_patching: bool = False
):
logger.info("--[ Compile C to ASM: {} -> {} ".format(c_in, asm_out))
@@ -38,12 +39,10 @@ def compile(
observer.add_text("carrier_asm_orig", file_readall_text(asm_out))
# DataReuse first
asmFileParser = AsmFileParser(asm_out)
asmFileParser = ReusedataAsmFileParser(asm_out)
asmFileParser.init()
data_fixups = asmFileParser.fixup_data_reuse()
data_fixup_entries = asmFileParser.get_data_reuse_entries()
config.data_fixups = data_fixups
config.data_fixup_entries = data_fixup_entries
asmFileParser.process()
carrier.set_datareuse_fixups(asmFileParser.get_reusedata_fixups())
asmFileParser.write_lines_to(asm_out)
# Assembly text fixup (SuperMega)
+25 -14
View File
@@ -1,9 +1,10 @@
import sys
import pefile
from intervaltree import Interval, IntervalTree
from typing import List
from typing import List, Dict
import os
from model.exehost import DataReuseEntry
class PeSection():
def __init__(self, pefile_section):
@@ -31,10 +32,15 @@ def bytes_to_asm_db(byte_data: bytes) -> bytes:
return "\tDB " + formatted_string
class AsmFileParser():
class ReusedataAsmFileParser():
def __init__(self, filepath):
self.filepath = filepath
self.lines = []
self.fixups: Dict[str, DataReuseEntry] = {}
def get_reusedata_fixups(self) -> List[DataReuseEntry]:
return list(self.fixups.values())
def init(self):
@@ -43,7 +49,12 @@ class AsmFileParser():
self.lines = [line.rstrip() for line in self.lines]
def fixup_data_reuse(self):
def process(self):
self.fixup_data_reuse_code()
self.fixup_data_reuse_data()
def fixup_data_reuse_code(self):
fixups = []
# lea rcx, OFFSET FLAT:$SG72513
for idx, line in enumerate(self.lines):
@@ -51,18 +62,13 @@ class AsmFileParser():
string_ref = line.split("OFFSET FLAT:")[1]
register = line.split("lea\t")[1].split(",")[0]
randbytes: bytes = os.urandom(7) # lea is 7 bytes
fixups.append({
"string_ref": string_ref,
"register": register,
"randbytes": randbytes,
})
self.fixups[string_ref] = DataReuseEntry(string_ref, register, randbytes)
self.lines[idx] = bytes_to_asm_db(randbytes) + " ; .rdata Reuse for {} ({})".format(
string_ref, register)
return fixups
def get_data_reuse_entries(self) -> List[str]:
entries = {}
def fixup_data_reuse_data(self) -> List[str]:
current_entry_name = ""
for line in self.lines:
@@ -79,7 +85,11 @@ class AsmFileParser():
elif part.endswith('H') or part.endswith('H,'):
hex = part.split('H')[0]
value += bytes.fromhex(hex)
entries[name] = value
if not name in self.fixups:
raise Exception("DataReuse: Entry {} not found in fixups".format(name))
self.fixups[name].data = value
elif line.startswith("\tDB"):
if current_entry_name == "":
@@ -97,12 +107,13 @@ class AsmFileParser():
#print("---> {}".format(hex))
value += bytes.fromhex(hex)
entries[current_entry_name] += value
if not name in self.fixups:
raise Exception("DataReuse: Entry {} not found in fixups".format(name))
self.fixups[name].data += value
else:
current_entry_name = ""
return entries
def write_lines_to(self, filename):
with open(filename, 'w',) as asmfile:
+21 -18
View File
@@ -64,14 +64,14 @@ def injected_fix_iat(exe_out: FilePath, carrier: Carrier, exe_host: ExeHost):
# get code section of exe_out
code = extract_code_from_exe(exe_out)
for iatEntry in carrier.get_all_iat_requests():
if not iatEntry.placeholder in code:
raise Exception("IatResolve ID {} not found, abort".format(iatEntry.placeholder))
addr = exe_host.get_addr_of_iat_function(iatEntry.name)
for IatRequest in carrier.get_all_iat_requests():
if not IatRequest.placeholder in code:
raise Exception("IatResolve ID {} not found, abort".format(IatRequest.placeholder))
addr = exe_host.get_addr_of_iat_function(IatRequest.name)
if addr == None:
raise Exception("IatResolve: Function {} not found".format(iatEntry.name))
raise Exception("IatResolve: Function {} not found".format(IatRequest.name))
off = code.index(iatEntry.placeholder)
off = code.index(IatRequest.placeholder)
current_address = off + exe_host.image_base + exe_host.code_virtaddr
#current_address += 2
destination_address = addr
@@ -81,13 +81,13 @@ def injected_fix_iat(exe_out: FilePath, carrier: Carrier, exe_host: ExeHost):
jmp = assemble_and_disassemble_jump(
current_address, destination_address
)
code = code.replace(iatEntry.placeholder, jmp)
code = code.replace(IatRequest.placeholder, jmp)
# write back our patched code into the exe
write_code_section(exe_file=exe_out, new_data=code)
def injected_fix_data(exe_path, data_fixups, data_fixup_entries, exe_host):
def injected_fix_data(exe_path, carrier: Carrier, exe_host: ExeHost):
data_reuser = DataReuser(exe_path)
data_reuser.init()
#ret = data_reuser.get_reloc_largest_gap(".rdata")
@@ -105,9 +105,11 @@ def injected_fix_data(exe_path, data_fixups, data_fixup_entries, exe_host):
print("Write into .data:".format())
data_reuser.pe.close()
reusedata_fixups: List[DataReuseEntry] = carrier.get_all_reusedata_fixups()
with open(exe_path, "r+b") as f:
for fixup in data_fixups:
var_data = data_fixup_entries[fixup["string_ref"]]
for datareuse_fixup in reusedata_fixups:
var_data = datareuse_fixup.data
print(" Addr: {} / 0x{:X} Data: {}".format(
addr, addr, len(var_data)))
@@ -118,7 +120,7 @@ def injected_fix_data(exe_path, data_fixups, data_fixup_entries, exe_host):
f.write(var_data)
#f.write(b"AAAAAAAAAAAAAAAAAAAAAAAAAAA")
print("ADD: 0x{:X} 0x{:X} 0x{:X}".format(addr, sect.virt_addr, exe_host.image_base))
fixup["addr"] = addr + sect.virt_addr + exe_host.image_base - sect.raw_addr
datareuse_fixup.addr = addr + sect.virt_addr + exe_host.image_base - sect.raw_addr
addr += len(var_data) + 8
#data_reuser.pe.write(exe_path + ".tmp")
#data_reuser.pe.close()
@@ -126,20 +128,21 @@ def injected_fix_data(exe_path, data_fixups, data_fixup_entries, exe_host):
# patch code section
code = extract_code_from_exe(exe_path)
for fixup in data_fixups:
if not fixup["randbytes"] in code:
raise Exception("DataResuse: ID {} not found, abort".format(fixup["randbytes"]))
for datareuse_fixup in reusedata_fixups:
if not datareuse_fixup.randbytes in code:
raise Exception("DataResuse: ID {} not found, abort".format(
datareuse_fixup.randbytes))
off = code.index(fixup["randbytes"])
off = code.index(datareuse_fixup.randbytes)
current_address = off + exe_host.image_base + exe_host.code_virtaddr
destination_address = fixup["addr"]
destination_address = datareuse_fixup.addr
logger.info(" Replace at 0x{:x} with call to 0x{:x}".format(
current_address, destination_address
))
lea = assemble_lea(
current_address, destination_address, fixup["register"]
current_address, destination_address, datareuse_fixup.register
)
code = code.replace(fixup["randbytes"], lea)
code = code.replace(datareuse_fixup.randbytes, lea)
# write back our patched code into the exe
write_code_section(exe_file=exe_path, new_data=code)
+2 -2
View File
@@ -167,6 +167,7 @@ def start(settings: Settings):
c_in = main_c_file,
asm_out = main_asm_file,
payload_len = project.payload.len,
carrier = project.carrier,
short_call_patching = project.settings.short_call_patching)
# Decide if we can use IAT_REUSE (all function calls available as import)
@@ -262,8 +263,7 @@ def start(settings: Settings):
# TODO IF?
phases.injector.injected_fix_data(
settings.inject_exe_out,
config.data_fixups,
config.data_fixup_entries,
project.carrier,
project.exe_host)
code = extract_code_from_exe(settings.inject_exe_out)