Hide the python-script from user

[hlubenow]

hlubenow wrote:

> ts-dev wrote:
> 
>> On Apr 6, 3:19 pm, hlubenow <hluben... at gmx.net> wrote:
>>> recently there was a thread about hiding the python-script from the
>>> user. The OP could use
>> 
>> Interesting - thanks
> 
> Well, testing it, it doesn't seem to work very well ...
> 
> It seems, Python-code is rather difficult to obfuscate, probably because
> of its clear syntax and indentations. Here's yet another approach:
> 
>
http://pythonhacker.is-a-geek.net/my_programs/pyfuscate/pyfuscate-0.1.zip/view
> 
> H.

That didn't work very well either :(.

Ok, but now I can offer a real secure solution:

You can have real encryption in Python using this modules:


http://www.amk.ca/files/python/crypto/pycrypto-2.0.1.tar.gz

and

http://sourceforge.net/projects/yawpycrypto 

Below I post a code-example that I've written some time ago. With it,
encrypting text is rather easy.

Then you have to program a start-script, that reads in your script and the
decryption-key. The decryption-key must be encrypted too. Such a encrypted
key can be generated by the modules if you don't pass a password to my
function "doEncrypt(). The decryption-key must then be hidden somewhere
within the encrypted program-script. That's because, if the user knows
where to find the key, he can decrypt the program-script.

If your start-script is written, everything should work automatically, one
shouldn't nearly notice the decryption-process.

Ok, here's my example code, how to encrypt and decrypt some text with the
modules:

----------------------------------------------------------------------------

#!/usr/bin/env python

import os
import sys
import base64

from yawPyCrypto.Cipher import DecryptCipher, EncryptCipher
from yawPyCrypto.Cipher import ZipDecryptCipher, ZipEncryptCipher
from yawPyCrypto.Constants import CIPHER_BLOWFISH, MODE_CBC


def doEncrypt(text, passw = None):

    e = EncryptCipher(passw, CIPHER_BLOWFISH, MODE_CBC)
    e.feed(text)
    e.finish()
    encryptedtext = e.data

    if passw != None:
        passwr = passw
    else:
        passwr = e.password

    a = (encryptedtext, passwr)
    return a


def doDecrypt(encryptedtext, passw):
    d = DecryptCipher(passw)
    d.feed(encryptedtext)
    d.finish()
    decoded = (d.data)
    return decoded


# Calling the encryption routine.
# If you just pass the text to encrypt, a password is generated:

a = doEncrypt("For your eyes only !", "Melina")


# Just trying to clean the screen:

if sys.platform == "win32":
    os.system("cls")
else:
    os.system("clear")

print
print "Hello !"
print
print "I just encrypted some text. It looks like this now:"
print

print base64.b64encode(a[0])

print
print 'Please notice, that I just encoded the text once more using
"base64.b64encode()" to make it printable.'
print
print "The password for decryption is: "
print
print base64.b64encode(a[1])
print
print "Let's decrypt again (the original password must be passed without
b64encoding):"
print
print doDecrypt(a[0], a[1])
print

----------------------------------------------------------------------------

See you

H.