#!/usr/bin/env python3 -B
# coding=utf-8
"""
AMI PFAT Extract
AMI BIOS Guard Extractor
Copyright (C) 2018-2024 Plato Mavropoulos
"""
import ctypes
import os
import re
import struct
from typing import Any, Final, Type
from biosutilities.common.externals import big_script_tool
from biosutilities.common.paths import extract_suffix, extract_folder, make_dirs, path_name, safe_name
from biosutilities.common.patterns import PAT_AMI_PFAT
from biosutilities.common.structs import CHAR, ctypes_struct, UINT8, UINT16, UINT32
from biosutilities.common.system import printer
from biosutilities.common.templates import BIOSUtility
from biosutilities.common.texts import bytes_to_hex, file_to_bytes, to_ordinal
class AmiBiosGuardHeader(ctypes.LittleEndianStructure):
""" AMI BIOS Guard Header """
_pack_ = 1
_fields_ = [
('Size', UINT32), # 0x00 Header + Entries
('Checksum', UINT32), # 0x04 ?
('Tag', CHAR * 8), # 0x04 _AMIPFAT
('Flags', UINT8) # 0x10 ?
# 0x11
]
def struct_print(self, padding: int = 0) -> None:
""" Display structure information """
printer(message=['Size :', f'0x{self.Size:X}'], padding=padding, new_line=False)
printer(message=['Checksum:', f'0x{self.Checksum:04X}'], padding=padding, new_line=False)
printer(message=['Tag :', self.Tag.decode('utf-8')], padding=padding, new_line=False)
printer(message=['Flags :', f'0x{self.Flags:02X}'], padding=padding, new_line=False)
class IntelBiosGuardHeader(ctypes.LittleEndianStructure):
""" Intel BIOS Guard Header """
_pack_ = 1
_fields_ = [
('BGVerMajor', UINT16), # 0x00
('BGVerMinor', UINT16), # 0x02
('PlatformID', UINT8 * 16), # 0x04
('Attributes', UINT32), # 0x14
('ScriptVerMajor', UINT16), # 0x16
('ScriptVerMinor', UINT16), # 0x18
('ScriptSize', UINT32), # 0x1C
('DataSize', UINT32), # 0x20
('BIOSSVN', UINT32), # 0x24
('ECSVN', UINT32), # 0x28
('VendorInfo', UINT32) # 0x2C
# 0x30
]
def get_platform_id(self) -> str:
""" Get Intel BIOS Guard Platform ID """
id_byte: bytes = bytes(self.PlatformID)
id_text: str = re.sub(r'[\n\t\r\x00 ]', '', id_byte.decode('utf-8', 'ignore'))
id_hexs: str = f'{int.from_bytes(id_byte, byteorder="big"):0{0x10 * 2}X}'
id_guid: str = f'{{{id_hexs[:8]}-{id_hexs[8:12]}-{id_hexs[12:16]}-{id_hexs[16:20]}-{id_hexs[20:]}}}'
return f'{id_text} {id_guid}'
def get_hdr_marker(self) -> bytes:
""" Get Intel BIOS Guard Header Marker """
return struct.pack('<HH16B', self.BGVerMajor, self.BGVerMinor, *self.PlatformID)
def get_flags(self) -> tuple:
""" Get Intel BIOS Guard Header Attributes """
attr: IntelBiosGuardHeaderGetAttributes = IntelBiosGuardHeaderGetAttributes()
attr.asbytes = self.Attributes # pylint: disable=attribute-defined-outside-init
return attr.b.SFAM, attr.b.ProtectEC, attr.b.GFXMitDis, attr.b.FTU, attr.b.Reserved
def struct_print(self, padding: int = 0) -> None:
""" Display structure information """
no_yes: dict[int, str] = {0: 'No', 1: 'Yes'}
sfam, ec_opc, gfx_dis, ft_upd, attr_res = self.get_flags()
bg_version: str = f'{self.BGVerMajor}.{self.BGVerMinor}'
script_version: str = f'{self.ScriptVerMajor}.{self.ScriptVerMinor}'
printer(message=['BIOS Guard Version :', bg_version], padding=padding, new_line=False)
printer(message=['Platform Identity :', self.get_platform_id()], padding=padding, new_line=False)
printer(message=['Signed Flash Address Map :', no_yes[sfam]], padding=padding, new_line=False)
printer(message=['Protected EC OpCodes :', no_yes[ec_opc]], padding=padding, new_line=False)
printer(message=['Graphics Security Disable :', no_yes[gfx_dis]], padding=padding, new_line=False)
printer(message=['Fault Tolerant Update :', no_yes[ft_upd]], padding=padding, new_line=False)
printer(message=['Attributes Reserved :', f'0x{attr_res:X}'], padding=padding, new_line=False)
printer(message=['Script Version :', script_version], padding=padding, new_line=False)
printer(message=['Script Size :', f'0x{self.ScriptSize:X}'], padding=padding, new_line=False)
printer(message=['Data Size :', f'0x{self.DataSize:X}'], padding=padding, new_line=False)
printer(message=['BIOS Security Version Number:', f'0x{self.BIOSSVN:X}'], padding=padding, new_line=False)
printer(message=['EC Security Version Number :', f'0x{self.ECSVN:X}'], padding=padding, new_line=False)
printer(message=['Vendor Information :', f'0x{self.VendorInfo:X}'], padding=padding, new_line=False)
class IntelBiosGuardHeaderAttributes(ctypes.LittleEndianStructure):
""" Intel BIOS Guard Header Attributes """
_pack_ = 1
_fields_ = [
('SFAM', UINT32, 1), # Signed Flash Address Map
('ProtectEC', UINT32, 1), # Protected EC OpCodes
('GFXMitDis', UINT32, 1), # GFX Security Disable
('FTU', UINT32, 1), # Fault Tolerant Update
('Reserved', UINT32, 28) # Reserved/Unknown
]
class IntelBiosGuardHeaderGetAttributes(ctypes.Union):
""" Intel BIOS Guard Header Attributes Getter """
_pack_ = 1
_fields_ = [
('b', IntelBiosGuardHeaderAttributes),
('asbytes', UINT32)
]
class IntelBiosGuardSignatureHeader(ctypes.LittleEndianStructure):
""" Intel BIOS Guard Signature Header """
_pack_ = 1
_fields_ = [
('Unknown0', UINT32), # 0x000
('Unknown1', UINT32) # 0x004
# 0x8
]
def struct_print(self, padding: int = 0) -> None:
""" Display structure information """
printer(message=['Unknown 0:', f'0x{self.Unknown0:X}'], padding=padding, new_line=False)
printer(message=['Unknown 1:', f'0x{self.Unknown1:X}'], padding=padding, new_line=False)
class IntelBiosGuardSignatureRsa2k(ctypes.LittleEndianStructure):
""" Intel BIOS Guard Signature Block 2048-bit """
_pack_ = 1
_fields_ = [
('Modulus', UINT8 * 256), # 0x000
('Exponent', UINT32), # 0x100
('Signature', UINT8 * 256) # 0x104
# 0x204
]
def struct_print(self, padding: int = 0) -> None:
""" Display structure information """
modulus: str = f'{bytes_to_hex(in_buffer=self.Modulus, order="little", data_len=0x100, slice_len=32)} [...]'
exponent: str = f'0x{self.Exponent:X}'
signature: str = f'{bytes_to_hex(in_buffer=self.Signature, order="little", data_len=0x100, slice_len=32)} [...]'
printer(message=['Modulus :', modulus], padding=padding, new_line=False)
printer(message=['Exponent :', exponent], padding=padding, new_line=False)
printer(message=['Signature:', signature], padding=padding, new_line=False)
class IntelBiosGuardSignatureRsa3k(ctypes.LittleEndianStructure):
""" Intel BIOS Guard Signature Block 3072-bit """
_pack_ = 1
_fields_ = [
('Modulus', UINT8 * 384), # 0x000
('Exponent', UINT32), # 0x180
('Signature', UINT8 * 384) # 0x184
# 0x304
]
def struct_print(self, padding: int = 0) -> None:
""" Display structure information """
modulus: str = f'{int.from_bytes(self.Modulus, byteorder="little"):0{0x180 * 2}X}'[:64]
exponent: str = f'0x{self.Exponent:X}'
signature: str = f'{int.from_bytes(self.Signature, byteorder="little"):0{0x180 * 2}X}'[:64]
printer(message=['Modulus :', modulus], padding=padding, new_line=False)
printer(message=['Exponent :', exponent], padding=padding, new_line=False)
printer(message=['Signature:', signature], padding=padding, new_line=False)
class AmiPfatExtract(BIOSUtility):
""" AMI BIOS Guard Extractor """
TITLE: str = 'AMI BIOS Guard Extractor'
PFAT_AMI_HDR_LEN: Final[int] = ctypes.sizeof(AmiBiosGuardHeader)
PFAT_INT_HDR_LEN: Final[int] = ctypes.sizeof(IntelBiosGuardHeader)
PFAT_INT_SIG_HDR_LEN: Final[int] = ctypes.sizeof(IntelBiosGuardSignatureHeader)
PFAT_INT_SIG_R2K_LEN: Final[int] = ctypes.sizeof(IntelBiosGuardSignatureRsa2k)
PFAT_INT_SIG_R3K_LEN: Final[int] = ctypes.sizeof(IntelBiosGuardSignatureRsa3k)
PFAT_INT_SIG_MAX_LEN: Final[int] = PFAT_INT_SIG_HDR_LEN + PFAT_INT_SIG_R3K_LEN
def check_format(self) -> bool:
""" Check if input is AMI BIOS Guard """
input_buffer: bytes = file_to_bytes(in_object=self.input_object)
return bool(self._get_ami_pfat(input_object=input_buffer))
def parse_format(self) -> bool:
""" Process and store AMI BIOS Guard output file """
input_buffer: bytes = file_to_bytes(in_object=self.input_object)
pfat_buffer: bytes = self._get_ami_pfat(input_object=input_buffer)
file_path: str = ''
all_blocks_dict: dict = {}
bg_sign_len: int = 0
extract_name: str = path_name(in_path=self.extract_path).removesuffix(extract_suffix())
make_dirs(in_path=self.extract_path, delete=True)
block_all, block_off, file_count = self._parse_pfat_hdr(buffer=pfat_buffer, padding=self.padding)
for block in block_all:
file_desc, file_name, _, _, _, file_index, block_index, block_count = block
if block_index == 0:
printer(message=file_desc, padding=self.padding + 4)
file_path = os.path.join(self.extract_path, self._get_file_name(index=file_index + 1, name=file_name))
all_blocks_dict[file_index] = b''
block_status: str = f'{block_index + 1}/{block_count}'
bg_hdr: Any = ctypes_struct(buffer=pfat_buffer, start_offset=block_off, class_object=IntelBiosGuardHeader)
printer(message=f'Intel BIOS Guard {block_status} Header:\n', padding=self.padding + 8)
bg_hdr.struct_print(padding=self.padding + 12)
bg_script_bgn: int = block_off + self.PFAT_INT_HDR_LEN
bg_script_end: int = bg_script_bgn + bg_hdr.ScriptSize
bg_data_bgn: int = bg_script_end
bg_data_end: int = bg_data_bgn + bg_hdr.DataSize
bg_data_bin: bytes = pfat_buffer[bg_data_bgn:bg_data_end]
block_off = bg_data_end # Assume next block starts at data end
is_sfam, _, _, _, _ = bg_hdr.get_flags() # SFAM, ProtectEC, GFXMitDis, FTU, Reserved
if is_sfam:
printer(message=f'Intel BIOS Guard {block_status} Signature:\n', padding=self.padding + 8)
# Manual BIOS Guard Signature length detection from Header pattern (e.g. Panasonic)
if bg_sign_len == 0:
bg_sign_sig: bytes = bg_hdr.get_hdr_marker()
bg_sign_lim: int = bg_data_end + self.PFAT_INT_SIG_MAX_LEN + len(bg_sign_sig)
bg_sign_len = pfat_buffer.find(bg_sign_sig, bg_data_end, bg_sign_lim) - bg_data_end
# Adjust next block to start after current block Data + Signature
block_off += self.parse_bg_sign(input_data=pfat_buffer, sign_offset=bg_data_end,
sign_length=bg_sign_len, print_info=True, padding=self.padding + 12)
printer(message=f'Intel BIOS Guard {block_status} Script:\n', padding=self.padding + 8)
_ = self.parse_bg_script(script_data=pfat_buffer[bg_script_bgn:bg_script_end], padding=self.padding + 12)
with open(file_path, 'ab') as out_dat:
out_dat.write(bg_data_bin)
all_blocks_dict[file_index] += bg_data_bin
if block_index + 1 == block_count:
ami_pfat_extract: AmiPfatExtract = AmiPfatExtract(
input_object=all_blocks_dict[file_index], extract_path=extract_folder(file_path),
padding=self.padding + 8)
if ami_pfat_extract.check_format():
ami_pfat_extract.parse_format()
pfat_oob_data: bytes = pfat_buffer[block_off:] # Store out-of-bounds data after the end of PFAT files
pfat_oob_name: str = self._get_file_name(index=file_count + 1, name=f'{extract_name}_OOB.bin')
pfat_oob_path: str = os.path.join(self.extract_path, pfat_oob_name)
with open(pfat_oob_path, 'wb') as out_oob:
out_oob.write(pfat_oob_data)
ami_pfat_extract = AmiPfatExtract(
input_object=pfat_oob_data, extract_path=extract_folder(pfat_oob_path), padding=self.padding)
if ami_pfat_extract.check_format():
ami_pfat_extract.parse_format()
in_all_data: bytes = b''.join([block[1] for block in sorted(all_blocks_dict.items())])
in_all_name: str = self._get_file_name(index=0, name=f'{extract_name}_ALL.bin')
in_all_path: str = os.path.join(self.extract_path, in_all_name)
with open(in_all_path, 'wb') as out_all:
out_all.write(in_all_data + pfat_oob_data)
return True
def parse_bg_sign(self, input_data: bytes, sign_offset: int, sign_length: int = 0,
print_info: bool = False, padding: int = 0) -> int:
""" Process Intel BIOS Guard Signature """
bg_sig_hdr: Any = ctypes_struct(buffer=input_data, start_offset=sign_offset,
class_object=IntelBiosGuardSignatureHeader)
if bg_sig_hdr.Unknown0 == 1:
bg_sig_rsa_struct: Any = IntelBiosGuardSignatureRsa2k # Unknown0/Unknown1 = 1,1
elif bg_sig_hdr.Unknown0 in (2, 3):
bg_sig_rsa_struct = IntelBiosGuardSignatureRsa3k # Unknown0/Unknown1 = 2/3, 3/5, 3/6
elif sign_length == self.PFAT_INT_SIG_HDR_LEN + self.PFAT_INT_SIG_R2K_LEN:
bg_sig_rsa_struct = IntelBiosGuardSignatureRsa2k
printer(message='Warning: Detected Intel BIOS Guard Signature 2K length via pattern!\n',
padding=padding, new_line=False)
elif sign_length == self.PFAT_INT_SIG_HDR_LEN + self.PFAT_INT_SIG_R3K_LEN:
bg_sig_rsa_struct = IntelBiosGuardSignatureRsa3k
printer(message='Warning: Detected Intel BIOS Guard Signature 3K length via pattern!\n',
padding=padding, new_line=False)
else:
bg_sig_rsa_struct = IntelBiosGuardSignatureRsa3k
printer(message='Error: Could not detect Intel BIOS Guard Signature length, assuming 3K!\n',
padding=padding, new_line=False)
bg_sig_rsa: Any = ctypes_struct(buffer=input_data, start_offset=sign_offset + self.PFAT_INT_SIG_HDR_LEN,
class_object=bg_sig_rsa_struct)
if print_info:
bg_sig_hdr.struct_print(padding=padding)
bg_sig_rsa.struct_print(padding=padding)
# Total size of Signature Header and RSA Structure
return self.PFAT_INT_SIG_HDR_LEN + ctypes.sizeof(bg_sig_rsa_struct)
@staticmethod
def _get_ami_pfat(input_object: str | bytes | bytearray) -> bytes:
""" Get actual AMI BIOS Guard buffer """
input_buffer: bytes = file_to_bytes(in_object=input_object)
match: re.Match[bytes] | None = PAT_AMI_PFAT.search(input_buffer)
return input_buffer[match.start() - 0x8:] if match else b''
@staticmethod
def _get_file_name(index: int, name: str) -> str:
""" Create AMI BIOS Guard output filename """
return safe_name(in_name=f'{index:02d} -- {name}')
@staticmethod
def parse_bg_script(script_data: bytes, padding: int = 0) -> int:
""" Process Intel BIOS Guard Script """
is_opcode_div: bool = len(script_data) % 8 == 0
if not is_opcode_div:
printer(message='Error: BIOS Guard script is not divisible by OpCode length!',
padding=padding, new_line=False)
return 1
is_begin_end: bool = script_data[:8] + script_data[-8:] == b'\x01' + b'\x00' * 7 + b'\xFF' + b'\x00' * 7
if not is_begin_end:
printer(message='Error: BIOS Guard script lacks Begin and/or End OpCodes!',
padding=padding, new_line=False)
return 2
big_script: Type | None = big_script_tool()
if not big_script:
printer(message='Note: BIOS Guard Script Tool optional dependency is missing!',
padding=padding, new_line=False)
return 3
script: list[str] = big_script(code_bytes=script_data).to_string().replace('\t', ' ').split('\n')
for opcode in script:
if opcode.endswith(('begin', 'end')):
spacing: int = padding
elif opcode.endswith(':'):
spacing = padding + 4
else:
spacing = padding + 12
operands: list[str] = [operand for operand in opcode.split(' ') if operand]
# Largest opcode length is 11 (erase64kblk) and largest operand length is 10 (0xAABBCCDD).
printer(message=f'{operands[0]:11s}{"".join((f" {o:10s}" for o in operands[1:]))}',
padding=spacing, new_line=False)
return 0
def _parse_pfat_hdr(self, buffer: bytes | bytearray, padding: int = 0) -> tuple:
""" Parse AMI BIOS Guard Header """
block_all: list = []
pfat_hdr: Any = ctypes_struct(buffer=buffer, start_offset=0, class_object=AmiBiosGuardHeader)
hdr_size: int = pfat_hdr.Size
hdr_data: bytes = buffer[self.PFAT_AMI_HDR_LEN:hdr_size]
hdr_text: list[str] = hdr_data.decode('utf-8').splitlines()
printer(message='AMI BIOS Guard Header:\n', padding=padding)
pfat_hdr.struct_print(padding=padding + 4)
hdr_title, *hdr_files = hdr_text
files_count: int = len(hdr_files)
hdr_tag, *hdr_indexes = hdr_title.split('II')
printer(message=hdr_tag + '\n', padding=padding + 4)
bgt_indexes: list = [int(h, 16) for h in re.findall(r'.{1,4}', hdr_indexes[0])] if hdr_indexes else []
for index, entry in enumerate(hdr_files):
entry_parts: list = entry.split(';')
info: list = entry_parts[0].split()
name: str = entry_parts[1]
flags: int = int(info[0])
param: str = info[1]
count: int = int(info[2])
order: str = to_ordinal(in_number=(bgt_indexes[index] if bgt_indexes else index) + 1)
desc = f'{name} (Index: {index + 1:02d}, Flash: {order}, ' \
f'Parameter: {param}, Flags: 0x{flags:X}, Blocks: {count})'
block_all += [(desc, name, order, param, flags, index, i, count) for i in range(count)]
for block in block_all:
if block[6] == 0:
printer(message=block[0], padding=padding + 8, new_line=False)
return block_all, hdr_size, files_count