A python m2crypto usage example, simply encrypt/decrypting AES-128/ECB

m2crypt.py

#!/bin/env python
# m2crypt.py <mode> <key> <data>

import M2Crypto
import binascii
import sys

mode = sys.argv[1]
key = sys.argv[2]
data = sys.argv[3]

def get_cryptor( op, key, alg='aes_128_ecb', iv=None ):
    if iv == None:
        iv = '\0' * 16
    cryptor = M2Crypto.EVP.Cipher( alg=alg, key=key, iv=iv, op=op)
    return cryptor

def encrypt( key, plaintext ):
    cryptor = get_cryptor( 1, key )
    ret = cryptor.update( plaintext )
    ret = ret + cryptor.final()
    ret = binascii.hexlify( ret )
    return ret

def decrypt( key, ciphertext ):
    cryptor = get_cryptor( 0, key )
    ciphertext = binascii.unhexlify( ciphertext )
    ret = cryptor.update( ciphertext )
    ret = ret + cryptor.final()
    return ret

if mode == 'ENC':
    print encrypt( key, data )
elif mode == 'DEC':
    print decrypt( key, data )
else:
    sys.exit(1)

Hi ,

I am new to python. While decrypt i am getting below error. Can you please help

Traceback (most recent call last):
File "./crypto.py", line 61, in
print decrypt( key, data )
File "./crypto.py", line 55, in decrypt
ret = ret + cryptor.final()
File "/usr/lib64/python2.7/site-packages/M2Crypto/EVP.py", line 128, in final
return m2.cipher_final(self.ctx)
M2Crypto.EVP.EVPError: bad decrypt

Please follow the below ref to solve the problem related to M2Crypto

Link : https://stackoverflow.com/questions/73268630/error-could-not-build-wheels-for-pyaudio-which-is-required-to-install-pyprojec
Link2 : https://stackoverflow.com/questions/33005354/trouble-installing-m2crypto-with-pip-on-os-x-macos