48 lines
1.3 KiB
Python
48 lines
1.3 KiB
Python
|
#!/usr/bin/env python3
|
||
|
|
import sys
|
||
|
|
import struct
|
||
|
|
|
||
|
|
def align(num, alignment):
|
||
|
|
if num % alignment != 0:
|
||
|
|
num += (alignment - num % alignment)
|
||
|
|
return num
|
||
|
|
|
||
|
|
|
||
|
|
def process_file(input, output):
|
||
|
|
with open(input, 'rb') as fin:
|
||
|
|
content = bytearray(fin.read())
|
||
|
|
|
||
|
|
align_value = 512
|
||
|
|
padded_length = align(len(content), align_value)
|
||
|
|
# pad file to actual length
|
||
|
|
content += b'\x00' * (padded_length - len(content))
|
||
|
|
|
||
|
|
struct_format = '<L8sLL'
|
||
|
|
(instruction, magic, checksum, length) = struct.unpack_from(struct_format, content)
|
||
|
|
|
||
|
|
if magic != b'eGON.BT0':
|
||
|
|
print("Magic is invalid:", magic)
|
||
|
|
return 2
|
||
|
|
|
||
|
|
checksum = 0x5F0A6C39
|
||
|
|
length = align(length, align_value)
|
||
|
|
|
||
|
|
struct.pack_into(struct_format, content, 0, instruction, magic, checksum, length)
|
||
|
|
|
||
|
|
checksum = 0
|
||
|
|
for i in range(0, length, 4):
|
||
|
|
(n, ) = struct.unpack_from('<L', content, i)
|
||
|
|
checksum += n
|
||
|
|
checksum %= 4294967296
|
||
|
|
|
||
|
|
struct.pack_into(struct_format, content, 0, instruction, magic, checksum, length)
|
||
|
|
|
||
|
|
with open(output, 'wb') as fout:
|
||
|
|
fout.write(content)
|
||
|
|
return 0
|
||
|
|
|
||
|
|
if __name__ == "__main__":
|
||
|
|
if len(sys.argv) != 3:
|
||
|
|
print("Usage: mksunxi.py input.bin output.bin")
|
||
|
|
exit(1)
|
||
|
|
exit(process_file(sys.argv[1], sys.argv[2]))
|