What crypto should be used in PHP for crypting passwords?

Question

Thinking about to write a PHP script storing passwords in a DB, what php-crypto-function should i use? Hashing is not an option, cause the passwords have to be stored cryted and able to be encrypted, so the user can see them.

Answer 1

Given your product's code function is to allow the user to view passwords, symmetric encryption is what you want.

Check out the API docs for mcrypt (MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC)