DES encryption and decryption packaging class implemented in PHP

<?php
/**
* PHP版DES加解密类
* 可与java的DES(DESede/CBC/PKCS5Padding)加密方式兼容
*
*/
class CryptDes {
   var $key;
   var $iv;
   function CryptDes($key, $iv){
    $this->key = $key;
    $this->iv = $iv;
   }
   function encrypt($input){
     $size = mcrypt_get_block_size(MCRYPT_DES,MCRYPT_MODE_CBC); //3DES加密将MCRYPT_DES改为MCRYPT_3DES
     $input = $this->pkcs5_pad($input, $size); //如果采用PaddingPKCS7，请更换成PaddingPKCS7方法。
     $key = str_pad($this->key,8,&#39;0&#39;); //3DES加密将8改为24
     $td = mcrypt_module_open(MCRYPT_DES, &#39;&#39;, MCRYPT_MODE_CBC, &#39;&#39;);
     if( $this->iv == &#39;&#39; )
     {
       $iv = @mcrypt_create_iv (mcrypt_enc_get_iv_size($td), MCRYPT_RAND);
     }
     else
     {
       $iv = $this->iv;
     }
     @mcrypt_generic_init($td, $key, $iv);
     $data = mcrypt_generic($td, $input);
     mcrypt_generic_deinit($td);
     mcrypt_module_close($td);
     $data = base64_encode($data);//如需转换二进制可改成 bin2hex 转换
     return $data;
   }
   function decrypt($encrypted){
     $encrypted = base64_decode($encrypted); //如需转换二进制可改成 bin2hex 转换
     $key = str_pad($this->key,8,&#39;0&#39;); //3DES加密将8改为24
     $td = mcrypt_module_open(MCRYPT_DES,&#39;&#39;,MCRYPT_MODE_CBC,&#39;&#39;);//3DES加密将MCRYPT_DES改为MCRYPT_3DES
     if( $this->iv == &#39;&#39; )
     {
       $iv = @mcrypt_create_iv (mcrypt_enc_get_iv_size($td), MCRYPT_RAND);
     }
     else
     {
       $iv = $this->iv;
     }
     $ks = mcrypt_enc_get_key_size($td);
     @mcrypt_generic_init($td, $key, $iv);
     $decrypted = mdecrypt_generic($td, $encrypted);
     mcrypt_generic_deinit($td);
     mcrypt_module_close($td);
     $y=$this->pkcs5_unpad($decrypted);
     return $y;
   }
   function pkcs5_pad ($text, $blocksize) {
     $pad = $blocksize - (strlen($text) % $blocksize);
     return $text . str_repeat(chr($pad), $pad);
   }
   function pkcs5_unpad($text){
     $pad = ord($text{strlen($text)-1});
     if ($pad > strlen($text)) {
       return false;
     }
     if (strspn($text, chr($pad), strlen($text) - $pad) != $pad){
       return false;
     }
     return substr($text, 0, -1 * $pad);
   }
   function PaddingPKCS7($data) {
     $block_size = mcrypt_get_block_size(MCRYPT_DES, MCRYPT_MODE_CBC);//3DES加密将MCRYPT_DES改为MCRYPT_3DES
     $padding_char = $block_size - (strlen($data) % $block_size);
     $data .= str_repeat(chr($padding_char),$padding_char);
     return $data;
   }
}
$des = new CryptDes("12345678","12345678");//（秘钥向量，混淆向量）
echo $ret = $des->encrypt("1111");//加密字符串
?>