Completed challenge 238

238/code.py

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+
+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()
+

238/codebook.txt

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+azbycxdwevfugthsirjqkplomn