urlobfuscator.py

#!/usr/bin/env python
from Crypto.Cipher import AES
from Crypto import Random
import sys
import base64
import getopt

BS = 16
pad = lambda s: s + (BS - len(s) % BS) * chr(BS - len(s) % BS)
unpad = lambda s: s[:-ord(s[len(s) - 1:])]


class AESCipher:
    def __init__(self, key):
        self.key = key

    def encrypt(self, raw):
        raw = pad(raw)
        iv = Random.new().read(AES.block_size)
        cipher = AES.new(self.key, AES.MODE_CBC, iv)
        return base64.b64encode(iv + cipher.encrypt(raw))

    def decrypt(self, enc):
        enc = base64.b64decode(enc)
        iv = enc[:16]
        cipher = AES.new(self.key, AES.MODE_CBC, iv)
        return unpad(cipher.decrypt(enc[16:]))


def usage():
    print " python urlshortner.py 'URL' "
    print "   -e     Encrypt URL"
    print "   -d     Decrypt URL"


def main():
    try:
        opts, args = getopt.getopt(sys.argv[1:], "e:d:h", ["encrypt=", "decrypt=", "help"])
    except getopt.GetoptError as err:
        # print help information and exit:
        print str(err)  # will print something like "option -a not recognized"
        usage()
        sys.exit(2)
    encrypt_url = None
    decrypt_url = None
    for o, a in opts:
        if o in ("-h", "--help"):
            usage()
            sys.exit()
        elif o in ("-e", "--encrypt"):
            print "I am encrypting"
            encrypt_url = a
        elif o in ("-d", "--decrypt"):
            print "I am in decrypt"
            decrypt_url = a
        else:
            assert False, "unhandled option"

    aes = AESCipher("6wVqvzotCxFsjg==6wVqvzotCxFsjg==")
    if encrypt_url:
        print "encrypt:'%s'" % aes.encrypt(encrypt_url)
    elif decrypt_url:
        print "decrypt:'%s'" % aes.decrypt(decrypt_url)
    else:
        usage()
        sys.exit(2)

if __name__ == '__main__':
            main()