(PHP 5 >= 5.1.2, PHP 7, PECL hash >= 1.1) Return a list of registered hashing algorithms

(PHP 4, PHP 5, PHP 7) Gets the key size of the specified cipher

(PHP 4 >= 4.0.6, PHP 5, PHP 7) Verifies if a certificate can be used for a particular purpose

(PHP 5 >= 5.6.0, PHP 7) Timing attack safe string comparison

(PHP 4 >= 4.0.2, PHP 5, PHP 7) Returns the blocksize of the opened algorithm

(PHP 5 >= 5.3.0, PHP 7) Computes a digest

(PHP 4 >= 4.0.2, PHP 5, PHP 7) Returns if the specified mode outputs blocks or not

(PHP 4 >= 4.0.4, PHP 5, PHP 7) Open sealed data

(PECL crack >= 0.1) Returns the message from the last obscure check

(PHP 5 >= 5.5.0, PHP 7) Creates a password hash