MalRE decrypt script - Exercise

malre.py

# Mal-RE Decrypt script by @larsborn
####################################

import  binascii
import struct

buffer = binascii.unhexlify(b'')

def DecryptBlock(param_1: int, param_2: int) -> :
	return (((param_1 ^ param_2) << 4 | (param_1 ^ param_2) >> 0x1

out = b''
for i in range(0, len(buffer), 4):
	block = struct.unpack('<I', buffer[i:i + 4])[0]
	decrypted_block = decrypt_block(block, 0x10a1)
	out += struct.pack('<I', decrypted_block)

print(hashlib.sha256(out).hexdigest())
with open('dump.bin', 'wb') as fp:
	fp.write(out)