php AesCrypter pkcs7 加解密

PHP aes加解密类

class AesCrypter {

private $key = 'php1234567890';
private $algorithm;
private $mode;

public function __construct($key = '', $algorithm = MCRYPT_RIJNDAEL_128,
    $mode = MCRYPT_MODE_CBC) {
    if (!empty($key)) {
        $this->key = $key;
    }
    $this->key = hash('sha256', $this->key, true);
    $this->algorithm = $algorithm;
    $this->mode = $mode;
}

public function encrypt($orig_data) {
    $encrypter = mcrypt_module_open($this->algorithm, '',
        $this->mode, '');
    $orig_data = $this->pkcs7padding(
        $orig_data, mcrypt_enc_get_block_size($encrypter)
    );
    mcrypt_generic_init($encrypter, $this->key, substr($this->key, 0, 16));
    $ciphertext = mcrypt_generic($encrypter, $orig_data);
    mcrypt_generic_deinit($encrypter);
    mcrypt_module_close($encrypter);
    return base64_encode($ciphertext);
}

public function decrypt($ciphertext) {
    $encrypter = mcrypt_module_open($this->algorithm, '',
        $this->mode, '');
    $ciphertext = base64_decode($ciphertext);
    mcrypt_generic_init($encrypter, $this->key, substr($this->key, 0, 16));
    $orig_data = mdecrypt_generic($encrypter, $ciphertext);
    mcrypt_generic_deinit($encrypter);
    mcrypt_module_close($encrypter);
    return $this->pkcs7unPadding($orig_data);
}

public function pkcs7padding($data, $blocksize) {
    $padding = $blocksize - strlen($data) % $blocksize;
    $padding_text = str_repeat(chr($padding), $padding);
    return $data . $padding_text;
}

public function pkcs7unPadding($data) {
    $length = strlen($data);
    $unpadding = ord($data[$length - 1]);
    return substr($data, 0, $length - $unpadding);
}

}