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dfeichti |
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#!/usr/bin/python
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################################################################
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# crypttest.py
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#
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# Version info: $Id: crypttest.py,v 1.2 2007/02/01 23:44:38 feichtinger Exp $
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################################################################
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import sys
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import getopt
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import os
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from Crypto.Cipher import Blowfish # DES,AES
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import base64
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#####################################################
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# PARAMETERS
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#
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# we use a 56 byte key
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key = 'abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabde'
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#####################################################
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def addPadding(s):
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r = 8 - len(s)%8
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ret = s + r * chr(r)
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return ret
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def encrypt(plain):
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obj = Blowfish.new(key, Blowfish.MODE_CBC,iv)
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plain=addPadding(plain)
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# prepend the iv to the encrypted string
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encr = iv + obj.encrypt(plain)
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encr64=base64.encodestring(encr)
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return encr64;
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def decrypt(encr64):
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decr64=base64.decodestring(encr64)
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# retrieve the iv from the encrypted string
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iv = decr64[0:8];
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decr64 = decr64[8:]
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obj = Blowfish.new(key, Blowfish.MODE_CBC,iv)
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decr = obj.decrypt(decr64)
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# remove any standard padding
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if ord(decr[-1]) <= 8:
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decr = decr.strip(decr[-1])
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return decr
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##############
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# MAIN
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(o,leftover)=getopt.getopt(sys.argv[1:],"edhi:")
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opts={}
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for k,v in o:
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opts[k] = v
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mode="e"
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if opts.has_key('-d'):
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mode="d"
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if opts.has_key('-i'):
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iv = opts['-i']
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else:
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iv = os.urandom(8)
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if len(iv) != 8:
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print 'Error: IV needs to have length = 8'
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sys.exit(1);
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text=leftover[0]
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if mode == 'e':
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encr=encrypt(text)
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if encr[-1] == '\n':
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encr = encr[:-1]
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print '>'+encr+'<'
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else:
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decr=''
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decr=decrypt(text)
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print '>'+decr+'<'
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sys.exit(0)
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#######################################################
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#print 'key:',key
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#print 'key length: ', len(key)
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#key = 'abcdefgh'
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# Some tests with other ciphers
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#
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#obj = DES.new(key, DES.MODE_ECB)
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#obj = AES.new(key, AES.MODE_ECB)
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#obj = Blowfish.new(key, Blowfish.MODE_CBC,'abcdefgh')
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#obj = Blowfish.new(key, Blowfish.MODE_CBC)
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#obj = Blowfish.new(key, Blowfish.MODE_ECB)
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#print "Key size: ", obj.key_size # 0 means variable key size
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#print "Block size: ", obj.block_size
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