<?php
class DES_JAVA{
    var $key;
    var $iv; //偏移量

    function DES_JAVA($key, $iv=0){
        $this->key = $key;
        if($iv == 0){
            $this->iv = $key;
        }else{
            $this->iv = $iv;
        }
    }
    //加密
    function encrypt($str){
        $size = mcrypt_get_block_size ( MCRYPT_DES, MCRYPT_MODE_CBC );
        $str = $this->pkcs5Pad ( $str, $size );

        $data=mcrypt_cbc(MCRYPT_DES, $this->key, $str, MCRYPT_ENCRYPT, $this->iv);
        return base64_encode($data);
    }
    //解密
    function decrypt($str){
        $str = base64_decode ($str);
        $str = mcrypt_cbc(MCRYPT_DES, $this->key, $str, MCRYPT_DECRYPT, $this->iv );
        $str = $this->pkcs5Unpad( $str );
        return $str;
    }
    function pkcs5Pad($text, $blocksize){
        $pad = $blocksize - (strlen ( $text ) % $blocksize);
        return $text . str_repeat ( chr ( $pad ), $pad );
    }
    function pkcs5Unpad($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 );
    }
}
