122 lines
2.9 KiB
Python
Executable File
122 lines
2.9 KiB
Python
Executable File
#!/usr/bin/env python3
|
|
"""
|
|
# SPDX-License-Identifier: GPL-2.0-or-later
|
|
#
|
|
# sercomm-kernel-header.py: Creates Sercomm kernel header
|
|
#
|
|
# Copyright © 2022 Mikhail Zhilkin
|
|
"""
|
|
|
|
import argparse
|
|
import binascii
|
|
import os
|
|
import struct
|
|
|
|
KERNEL_HEADER_SIZE = 0x100
|
|
PADDING = 0xff
|
|
ROOTFS_FAKE_HEADER = "UBI#"
|
|
|
|
def auto_int(x):
|
|
return int(x, 0)
|
|
|
|
def create_kernel_header(args):
|
|
out_file = open(args.header_file, "wb")
|
|
header = get_kernel_header(args)
|
|
out_file.write(header)
|
|
out_file.close()
|
|
|
|
def get_kernel_header(args):
|
|
header = bytearray([PADDING] * KERNEL_HEADER_SIZE)
|
|
|
|
struct.pack_into('<L', header, 0xc, 0xffffff02)
|
|
struct.pack_into('<L', header, 0x1c, 0x0)
|
|
struct.pack_into('<L', header, 0x34, 0x0)
|
|
struct.pack_into('<L', header, 0x10, args.kernel_offset)
|
|
struct.pack_into('<L', header, 0x28, args.rootfs_offset)
|
|
|
|
if (args.rootfs_file):
|
|
if (args.rootfs_checking_size):
|
|
rootfs_size = args.rootfs_checking_size
|
|
else:
|
|
rootfs_size = os.path.getsize(args.rootfs_file)
|
|
buf = open(args.rootfs_file,'rb').read(rootfs_size)
|
|
crc = binascii.crc32(buf) & 0xffffffff
|
|
else:
|
|
rootfs_size = len(ROOTFS_FAKE_HEADER)
|
|
crc = binascii.crc32(str.encode(ROOTFS_FAKE_HEADER)) & \
|
|
0xffffffff
|
|
struct.pack_into('<L', header, 0x2c, rootfs_size)
|
|
struct.pack_into('<L', header, 0x30, crc)
|
|
|
|
rootfs_end_offset = args.rootfs_offset + rootfs_size
|
|
struct.pack_into('<L', header, 0x4, rootfs_end_offset)
|
|
|
|
kernel_size = os.path.getsize(args.kernel_file)
|
|
struct.pack_into('<L', header, 0x14, kernel_size)
|
|
|
|
buf = open(args.kernel_file,'rb').read()
|
|
crc = binascii.crc32(buf) & 0xffffffff
|
|
struct.pack_into('<L', header, 0x18, crc)
|
|
|
|
crc = binascii.crc32(header) & 0xffffffff
|
|
struct.pack_into('<L', header, 0x8, crc)
|
|
|
|
struct.pack_into('<L', header, 0x0, 0x726553)
|
|
|
|
return header
|
|
|
|
def main():
|
|
global args
|
|
|
|
parser = argparse.ArgumentParser(description='This script generates \
|
|
a kernel header for the Sercomm mt7621 devices')
|
|
|
|
parser.add_argument('--kernel-image',
|
|
dest='kernel_file',
|
|
action='store',
|
|
type=str,
|
|
help='Path to a Kernel binary image')
|
|
|
|
parser.add_argument('--kernel-offset',
|
|
dest='kernel_offset',
|
|
action='store',
|
|
type=auto_int,
|
|
help='Kernel offset')
|
|
|
|
parser.add_argument('--rootfs-offset',
|
|
dest='rootfs_offset',
|
|
action='store',
|
|
type=auto_int,
|
|
help='RootFS offset')
|
|
|
|
parser.add_argument('--output-header',
|
|
dest='header_file',
|
|
action='store',
|
|
type=str,
|
|
help='Output kernel header file')
|
|
|
|
parser.add_argument('--rootfs-image',
|
|
dest='rootfs_file',
|
|
action='store',
|
|
type=str,
|
|
help='Path to RootFS binary image (optional)')
|
|
|
|
parser.add_argument('--rootfs-checking-size',
|
|
dest='rootfs_checking_size',
|
|
action='store',
|
|
type=auto_int,
|
|
help='Bytes count for CRC calculation (optional)')
|
|
|
|
args = parser.parse_args()
|
|
|
|
if ((not args.kernel_file) or
|
|
(not args.kernel_offset) or
|
|
(not args.rootfs_offset) or
|
|
(not args.header_file)):
|
|
parser.print_help()
|
|
exit()
|
|
|
|
create_kernel_header(args)
|
|
|
|
main()
|