#!/usr/bin/env python3 -B # coding=utf-8 """ Fujitsu SFX Extractor Fujitsu SFX BIOS Extractor Copyright (C) 2019-2024 Plato Mavropoulos """ import os import re from biosutilities.common.compression import is_szip_supported, szip_decompress from biosutilities.common.paths import delete_file, make_dirs from biosutilities.common.patterns import PAT_FUJITSU_SFX from biosutilities.common.system import printer from biosutilities.common.templates import BIOSUtility class FujitsuSfxExtract(BIOSUtility): """ Fujitsu SFX BIOS Extractor """ TITLE: str = 'Fujitsu SFX BIOS Extractor' def check_format(self) -> bool: """ Check if input is Fujitsu SFX image """ return bool(PAT_FUJITSU_SFX.search(self.input_buffer)) def parse_format(self) -> bool: """ Parse & Extract Fujitsu SFX image """ # Microsoft CAB Header XOR 0xFF match_cab: re.Match[bytes] | None = PAT_FUJITSU_SFX.search(self.input_buffer) if not match_cab: return False printer(message='Detected obfuscated CAB archive!', padding=self.padding) # Microsoft CAB Header XOR 0xFF starts after "FjSfxBinay" signature cab_start: int = match_cab.start() + 0xA # Get LE XOR-ed CAB size cab_size: int = int.from_bytes(self.input_buffer[cab_start + 0x8:cab_start + 0xC], byteorder='little') # Create CAB size XOR value xor_size: int = int.from_bytes(b'\xFF' * 0x4, byteorder='little') # Perform XOR 0xFF and get actual CAB size cab_size ^= xor_size printer(message='Removing obfuscation...', padding=self.padding + 4) # Get BE XOR-ed CAB data cab_data: int = int.from_bytes(self.input_buffer[cab_start:cab_start + cab_size], byteorder='big') # Create CAB data XOR value xor_data: int = int.from_bytes(b'\xFF' * cab_size, byteorder='big') # Perform XOR 0xFF and get actual CAB data raw_data: bytes = (cab_data ^ xor_data).to_bytes(cab_size, 'big') printer(message='Extracting archive...', padding=self.padding + 4) make_dirs(in_path=self.extract_path) cab_path: str = os.path.join(self.extract_path, 'FjSfxBinay.cab') # Create temporary CAB archive with open(cab_path, 'wb') as cab_file_object: cab_file_object.write(raw_data) if is_szip_supported(in_path=cab_path): if szip_decompress(in_path=cab_path, out_path=self.extract_path, in_name='FjSfxBinay CAB', padding=self.padding + 8, check=True): delete_file(in_path=cab_path) else: return False else: return False return True