my_xor02.py

#!/usr/bin/env python

'''
This script will XOR the data.
The key and the payload must be in hex format
The script is simplified from my_xor.py
'''

import binascii

enc = "f155f55cf610ee5feb5cfd"
key = "9930"
dec = ""

n = 2

## if key is single byte
if ( (len(key) / 2) == 1):
	m = 0
	for i in range(0, len(enc), n):
		dec += hex(int(enc[i:i+n], 16) ^ int(key[m:m+n], 16)).replace('0x', '').zfill(2)
		## I put zifll because I didn't want to lose the leading zero in hex
		## eg) 0xd -> 0x0d (this is what I want)
else:
	m = 0
	for i in range(0, len(enc), n):
		dec += hex(int(enc[i:i+n], 16) ^ int(key[m:m+n], 16)).replace('0x', '').zfill(2)
		m += n
		## if the key gets to end, set the key back to beginning.
		if (m >= len(key)):
			m = 0
print(dec)
#dec = dec.replace('0d0d', '0d0a') ## not sure why but when hex contains '0d0d' it doesn't print properly so replacing to '0d0a'
#print(binascii.unhexlify(dec))
print(repr(binascii.unhexlify(dec)))
print("")