mcrypt_encrypt to openssl_encrypt, and OPENSSL_ZERO_PADDING problems

Question

I have this mcrypt_encrypt call, for a given $key, $message and $iv:

$string = mcrypt_encrypt(MCRYPT_3DES         


        

Answer 1

mcrypt_encrypt uses zeroes to pad message to the block size. So you can add zeroes to the tail of your raw data, and then encrypt the block.

Using OPENSSL_RAW_DATA|OPENSSL_ZERO_PADDING should work. If it doesn't, then you can remove padding from the decrypted data by yourself.