AESencryption.php

<?php
    class AES 
    {
        public static function aes128Encrypt($key, $data) {
            if(16 !== strlen($key)) $key = hash('MD5', $key, true);
            $padding = 16 - (strlen($data) % 16);
            $data .= str_repeat(chr($padding), $padding);
            return base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $key, $data, MCRYPT_MODE_CBC, str_repeat("\0", 16)));
        }

        public static function aes256Encrypt($key, $data) {
            if(32 !== strlen($key)) $key = hash('SHA256', $key, true);
            $padding = 16 - (strlen($data) % 16);
            $data .= str_repeat(chr($padding), $padding);
            return base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $key, $data, MCRYPT_MODE_CBC, str_repeat("\0", 16)));
        }

        public static function aes128Decrypt($key, $data) {
            if(16 !== strlen($key)) $key = hash('MD5', $key, true);
            $data = base64_decode($data);
            $data = mcrypt_decrypt(MCRYPT_RIJNDAEL_128, $key, $data, MCRYPT_MODE_CBC, str_repeat("\0", 16));
            $padding = ord($data[strlen($data) - 1]); 
            return substr($data, 0, -$padding); 
        }

        public static function aes256Decrypt($key, $data) {
            if(32 !== strlen($key)) $key = hash('SHA256', $key, true);
            $data = base64_decode($data);
            $data = mcrypt_decrypt(MCRYPT_RIJNDAEL_128, $key, $data, MCRYPT_MODE_CBC, str_repeat("\0", 16));
            $padding = ord($data[strlen($data) - 1]); 
            return substr($data, 0, -$padding); 
        }
    }