2 way crypt image filename

Question

I would like to change an image filename with a crypted string.

I need also:

• Crypting more multiple time the original string with the same password, will return the same string
• The encrypted string should be decrypted (2 way crypt)

What php method could I use? I saw that mcrypt is not updated from lots of years, and openssl_crypt will return different encrypted strings each time I encrypt (even if the password is the same).

Thanks

Answer 1

openssl_encrypt & co should be fine. example:

<?php
$data='foo.jpg';
$method='AES-192-CBC';
$password='ogiughjklpdeorivjrhfnd';
$iv=base64_encode(random_bytes(10));
$encrypted=array();
for($i=0;$i<10;++$i){
    $encrypted[]=openssl_encrypt($data,$method,$password,0,$iv );
}
$decrypted=openssl_decrypt ($encrypted[0] ,$method ,$password,0,$iv);

var_dump($data,$encrypted[0],$decrypted,$data===$decrypted,$encrypted[2]===$encrypted[7],$encrypted);

quote openssl_crypt will return different encrypted strings each time I encrypt (even if the password is the same). - not with AES-192-CBC, as long as the password AND IV is identical. i think that's why IV's was invented in the first place, to prevent the same data to encrypt to the exact same encrypted form