Re: mcrypt_encrypt help needed

On Wed, Nov 30, 2011 at 10:18 PM, Adam Richardson <simpleshot@gmail.com> wrote: > On Wed, Nov 30, 2011 at 4:14 PM, Matijn Woudt <tijnema@gmail.com> wrote: > >> On Wed, Nov 30, 2011 at 9:57 PM, Rick Dwyer <rpdwyer@earthlink.net> wrote: >> > Hello all. >> > >> > I am using the following function to encrypt a string: >> > >> > define('SALT', 'myvalueforsalthere'); >> > >> > function encrypt($text) >> > { >> >    return trim(base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_256, SALT, >> > $text, MCRYPT_MODE_ECB, >> > mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, >> MCRYPT_MODE_ECB), >> > MCRYPT_RAND)))); >> > } >> > >> >> Can you post your decrypt function too? >> >> You create a random IV here, don't you need that IV to decrypt too? >> >> > You're normally right, Matijn, > > However, ECB mode doesn't use an IV, so even though he's generating an IV, > it's not being used (and, the benefit of an IV is one of the main reasons > you try to avoid ECB.) > > Adam Ah, I see, you're right. I thought he was using CBC (which I would recommend). That also means that example #1 is wrong at mcrypt_encrypt help page[1]. Matijn [1] http://php.net/manual/en/function.mcrypt-encrypt.php#example-884