lib/crapto/examples/repeating_key_xor_solve.nit

   1 # This file is part of NIT ( http://www.nitlanguage.org ).
   2 #
   3 # Licensed under the Apache License, Version 2.0 (the "License");
   4 # you may not use this file except in compliance with the License.
   5 # You may obtain a copy of the License at
   6 #
   7 #     http://www.apache.org/licenses/LICENSE-2.0
   8 #
   9 # Unless required by applicable law or agreed to in writing, software
  10 # distributed under the License is distributed on an "AS IS" BASIS,
  11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 # See the License for the specific language governing permissions and
  13 # limitations under the License.
  14
  15 import base64
  16 import crapto
  17
  18 # Check usage
  19 if args.length != 1 then
  20         print "Usage: repeating_key_xor_solve <cipher_file>"
  21         exit 1
  22 end
  23
  24 # Read the cipher from the file
  25 var cipher_bytes = args[0].to_path.read_all_bytes.decode_base64
  26
  27 # Create a RepeatingKeyXorCipher object to manipulate your ciphertext
  28 var xorcipher = new RepeatingKeyXorCipher
  29 xorcipher.ciphertext = cipher_bytes
  30
  31 # Try to find the best candidate key
  32 xorcipher.find_key
  33
  34 # Decrypt the cipher according to the found key
  35 xorcipher.decrypt
  36
  37 # Check the resulting plaintext out...
  38 print xorcipher.plaintext