refactor: put *manager back to superpe again

This commit is contained in:
Dobin Rutishauser
2024-06-23 17:07:21 +02:00
parent e10f9c7fda
commit fc64068139
4 changed files with 90 additions and 89 deletions
+80
View File
@@ -5,6 +5,7 @@ from typing import List, Dict
import random
from model.defs import *
from model.rangemanager import RangeManager
logger = logging.getLogger("superpe")
@@ -321,6 +322,66 @@ class SuperPe():
offset, func_name, new_name_bytes.decode()))
self.pe.set_bytes_at_offset(offset, new_name_bytes)
## .rdata manager
def get_rdata_rangemanager(self) -> RangeManager:
section = self.get_section_by_name(".rdata")
relocs = self.get_relocations_for_section(".rdata")
rm = RangeManager(section.virt_addr, section.virt_addr + section.virt_size)
for reloc in relocs:
# Reloc destination is probably 8 bytes
# But i add another 8 to skip over small holes (common in .rdata)
rm.add_range(reloc.rva, reloc.rva + 8 + 8)
if True: # FIXME this is a hack which is sometimes necessary?
sect_data_copy = section.pefile_section.get_data()
string_off = find_first_utf16_string_offset(sect_data_copy)
if string_off == None:
raise Exception("Strings not found in .rdata section, abort")
if string_off < 128:
logging.debug("weird: Strings in .rdata section at offset {} < 100".format(string_off))
string_off = 128
rm.add_range(section.virt_addr, section.virt_addr + string_off)
rm.merge_overlaps()
return rm
def get_relocations_for_section(self, section_name: str) -> List[PeRelocEntry]:
section: PeSection = self.get_section_by_name(section_name)
ret = []
if section is None:
return ret
for reloc in self.get_base_relocs():
reloc_addr = reloc.rva
if reloc_addr >= section.virt_addr and reloc_addr < section.virt_addr + section.virt_size:
#logger.info("ADDR: 0x{:X}".format(reloc_addr))
ret.append(reloc)
return ret
def get_code_rangemanager(self) -> RangeManager:
code_section = self.get_code_section()
if code_section == None:
raise Exception('Could not find code section in input PE file!')
code_section_size = code_section.Misc_VirtualSize
# Restrictions for putting data into .text:
# - enough space for carrier + payload
# - avoid overwriting entry point function
# - carrier should not generate much smaller holes in .text
rm = RangeManager(
code_section.VirtualAddress,
code_section.VirtualAddress + code_section_size)
# protect entrypoint a bit
entrypoint_rva = self.get_entrypoint()
rm.add_range(
entrypoint_rva - 0x100,
entrypoint_rva + 0x100)
return rm
## Helpers
@@ -351,3 +412,22 @@ class SuperPe():
self.pe.OPTIONAL_HEADER.DATA_DIRECTORY[SuperPe.IMAGE_DIRECTORY_ENTRY_SECURITY].VirtualAddress = 0
self.pe.OPTIONAL_HEADER.DATA_DIRECTORY[SuperPe.IMAGE_DIRECTORY_ENTRY_SECURITY].Size = 0
def find_first_utf16_string_offset(data, min_len=8):
current_string = bytearray()
start_offset = None # To keep track of the start of the current string
for i in range(0, len(data) - 1, 2):
# Check if we have a valid character
if data[i] != 0 or data[i+1] != 0:
if start_offset is None: # Mark the start of a new string
start_offset = i
current_string += bytes([data[i], data[i+1]])
else:
if len(current_string) >= min_len * 2: # Check if the current string meets the minimum length
return start_offset # Return the offset where the string starts
current_string = bytearray()
start_offset = None # Reset start offset for the next string
return None # No string found that meets the criteria