| import random | |
| import sys | |
| def str_xor(secret, key): | |
| #extend key to secret length | |
| new_key = key | |
| i = 0 | |
| while len(new_key) < len(secret): | |
| new_key = new_key + key[i] | |
| i = (i + 1) % len(key) | |
| return "".join([chr(ord(secret_c) ^ ord(new_key_c)) for (secret_c,new_key_c) in zip(secret,new_key)]) | |
| flag_enc = chr(0x13) + chr(0x01) + chr(0x17) + chr(0x07) + chr(0x2c) + chr(0x3a) + chr(0x2f) + chr(0x1a) + chr(0x0d) + chr(0x53) + chr(0x0c) + chr(0x47) + chr(0x0a) + chr(0x5f) + chr(0x5e) + chr(0x02) + chr(0x3e) + chr(0x5a) + chr(0x56) + chr(0x5d) + chr(0x45) + chr(0x5d) + chr(0x58) + chr(0x31) + chr(0x0d) + chr(0x58) + chr(0x0f) + chr(0x02) + chr(0x5a) + chr(0x10) + chr(0x0e) + chr(0x5d) + chr(0x13) | |
| def print_flag(): | |
| try: | |
| codebook = open('codebook.txt', 'r').read() | |
| password = codebook[4] + codebook[14] + codebook[13] + codebook[14] +\ | |
| codebook[23]+ codebook[25] + codebook[16] + codebook[0] +\ | |
| codebook[25] | |
| flag = str_xor(flag_enc, password) | |
| print(flag) | |
| except FileNotFoundError: | |
| print('Couldn\'t find codebook.txt. Did you download that file into the same directory as this script?') | |
| def main(): | |
| print_flag() | |
| if __name__ == "__main__": | |
| main() | |