今天写了一个php的AES加密类。适用于Yii的扩展。
如果不用在Yii框架中，把代码中Yii::app()->params['encryptKey'] 换成你对应的默认key就可以了。
类代码:

<?php/** * php AES加解密类 * 如果要与java共用，则密钥长度应该为16位长度 * 因为java只支持128位加密，所以php也用128位加密，可以与java互转。 * 同时AES的标准也是128位。只是RIJNDAEL算法可以支持128，192和256位加密。 * java 要使用AES/CBC/NoPadding标准来加解密 * * @author Terry * */class PhpAes{ /** * This was AES-128 / CBC / NoPadding encrypted. * return base64_encode string * @author Terry * @param string $plaintext * @param string $key */ public static function AesEncrypt($plaintext,$key = null) { $plaintext = trim($plaintext); if ($plaintext == '') return ''; if(!extension_loaded('mcrypt')) throw new CException(Yii::t('yii','AesEncrypt requires PHP mcrypt extension to be loaded in order to use data encryption feature.')); $size = mcrypt_get_block_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC); $module = mcrypt_module_open(MCRYPT_RIJNDAEL_128, '', MCRYPT_MODE_CBC, ''); $key=self::substr($key===null ? Yii::app()->params['encryptKey'] : $key, 0, mcrypt_enc_get_key_size($module)); /* Create the IV and determine the keysize length, use MCRYPT_RAND * on Windows instead */ $iv = substr(md5($key),0,mcrypt_enc_get_iv_size($module)); mcrypt_generic_init($module, $key, $iv); $encrypted = mcrypt_generic($module, $plaintext); mcrypt_generic_deinit($module); mcrypt_module_close($module); return base64_encode($encrypted); } /** * This was AES-128 / CBC / NoPadding decrypted. * @author Terry * @param string $encrypted base64_encode encrypted string * @param string $key * @throws CException * @return string */ public static function AesDecrypt($encrypted, $key = null) { if ($encrypted == '') return ''; if(!extension_loaded('mcrypt')) throw new CException(Yii::t('yii','AesDecrypt requires PHP mcrypt extension to be loaded in order to use data encryption feature.')); $ciphertext_dec = base64_decode($encrypted); $module = mcrypt_module_open(MCRYPT_RIJNDAEL_128, '', MCRYPT_MODE_CBC, ''); $key=self::substr($key===null ? Yii::app()->params['encryptKey'] : $key, 0, mcrypt_enc_get_key_size($module)); $iv = substr(md5($key),0,mcrypt_enc_get_iv_size($module)); mcrypt_generic_init($module, $key, $iv); $decrypted = mdecrypt_generic($module, $ciphertext_dec); mcrypt_generic_deinit($module); mcrypt_module_close($module); return rtrim($decrypted,"\0"); } /** * Returns the length of the given string. * If available uses the multibyte string function mb_strlen. * @param string $string the string being measured for length * @return integer the length of the string */ private static function strlen($string) { return extension_loaded('mbstring') ? mb_strlen($string,'8bit') : strlen($string); } /** * Returns the portion of string specified by the start and length parameters. * If available uses the multibyte string function mb_substr * @param string $string the input string. Must be one character or longer. * @param integer $start the starting position * @param integer $length the desired portion length * @return string the extracted part of string, or FALSE on failure or an empty string. */ private static function substr($string,$start,$length) { return extension_loaded('mbstring') ? mb_substr($string,$start,$length,'8bit') : substr($string,$start,$length); }}