PHP mcrypt to Python - php

Question

I'm trying to convert a PHP encryption function to Python. For the sake of the example and making things easier, the iv and relevant data is preset.
$salt = sha1('12345'.'654321');
encrypt('12345678', 'cutekittens12345', $salt);
function encrypt($decrypted, $password, $salt)
{
// Build a 256-bit $key which is a SHA256 hash of $salt and $password.
$key = hash('SHA256', $salt . $password, true);
$hexkey = hash('SHA256', $salt . $password, false);
// Build $iv and $iv_base64. We use a block size of 128 bits (AES compliant) and CBC mode. (Note: ECB mode is inadequate as IV is not used.)
#$iv = mcrypt_create_iv(16, MCRYPT_RAND);
$iv = "0000000000000000";
if (strlen($iv_base64 = rtrim(base64_encode($iv), '=')) != 22)
return false;
// Encrypt $decrypted and an MD5 of $decrypted using $key. MD5 is fine to use here because it's just to verify successful decryption.
$concatdecrypted = ($decrypted . md5($decrypted));
$encrypted = base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $key, $concatdecrypted, MCRYPT_MODE_CBC, $iv));
// We're done!
return $iv_base64 . $encrypted;
}
Which results in
$salt: 6ed52d21d5cc15e76e9879675f4bd0dd51593652
$hexkey: 879522bb98c1f5fb16acd6bf3454b0d4e313e8b71e0aa3cdf5cbf91158dfde71
$iv_base64: MDAwMDAwMDAwMDAwMDAwMA
$concatdecrypted: 1234567825d55ad283aa400af464c76d713c07ad
$encrypted: C3CWJPt2gtmg+id1ySmSazMvvWC7cgDpovJ/tDN0GeuVv9Pf/9+9ZSG+wjl6qD5h
My cleanest attempt at recreating the function is here and:
from base64 import b64encode, b64decode
from Crypto.Cipher import AES
import hashlib
charid = "654321"
apikey = "12345"
vcode = "12345678"
password = "cutekittens12345"
salt = hashlib.sha1((apikey + charid).encode('utf-8')).hexdigest()
key = hashlib.sha256(salt + password).digest()
iv = "0000000000000000"
concatkey = vcode + hashlib.md5(vcode).hexdigest()
AES.key_size=128
encryptor=AES.new(key=key,mode=AES.MODE_CBC,IV=iv)
encoded = encryptor.encrypt(concatkey_pad)
encoded = b64encode(encoded)
print 'Encrypted string:', encoded
I can recreate everything except the final result. I've tried a combination of unhex to see if it's something to do with passing raw inputs, but none of the $encrypted results have been a match.
Any help would be appreciated thank you.

Answer 1

I tried M2Crypto, Crypto.Cipher and pyDes. After reading 'Lessons learned implementing AES in PHP using Mcrypt' I had success with Crypto.Cipher after padding the string with ascii 0's to bypass the multiples of 16 issue and the first half of the encoded string was a match to my php function.
concatkey_pad = concatkey.ljust(48, '\0')
AES.key_size=128
encryptor=AES.new(key=key,mode=AES.MODE_CBC,IV=iv)
encoded = encryptor.encrypt(concatkey_pad)
encoded = b64encode(encoded)
print 'Encrypted string:', encoded
Padding concatkey with binary 0's using ljust generated the correct encoded value.