xor-file-encryptor.py

'''
This script will XOR encrypt the files in specified directory.
If you want to recover the encrypted files, simply run the script again with same XOR key.
'''

import os
import binascii

key = "This is the key"
key = binascii.hexlify(key)
key_hex = []
path = "/foo/bar/"
enc = ""

dir_list = os.listdir(path)

for file in dir_list:
	if not os.path.isdir(path + file):
		fout = open(path + file, 'rb')
		file_data = binascii.hexlify(fout.read())
		fout.close()
		
		for a, b in zip(key[::2], key[1::2]): ## get 2chars each from hex and join
			key_hex.append(''.join(a + b))
		
		cnt = 0
		
		for a, b in zip(file_data[::2], file_data[1::2]): ## get 2chars from hex and join
			rawdata = ''.join(a + b)
			if cnt >= len(key_hex): ## when the key gets to end, reset the key to beginning
				cnt = 0
			enc += hex(int(rawdata, 16) ^ int(key_hex[cnt], 16)).replace('0x', '').zfill(2)
			cnt += 1 
			## I put zfill because I didn't want to lose the leading zero in hex
			## eg) 0xd -> 0x0d (this is what I want)
		fin = open(path + file, 'wb')
		fin.write(binascii.unhexlify(enc))
		fin.close()
		enc = ""
print("Encrypted!")