PHP实现的DES加密解密类定义与用法示例

class CryptDes {  function __construct(){    $this->key = 'codelovers'; //密钥    $this->iv = '15548632'; //偏移量  }  /*   * 加密   */  function encrypt($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,'0'); //3DES加密将8改为24    $td = mcrypt_module_open(MCRYPT_DES, '', MCRYPT_MODE_CBC, '');    if( $this->iv == '' )    {      $iv = @mcrypt_create_iv (mcrypt_enc_get_iv_size($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 $data;  }  /*   * 解密   */  function decrypt($encrypted){    $encrypted = base64_decode($encrypted); //如需转换二进制可改成 bin2hex 转换    $key = str_pad($this->key,8,'0'); //3DES加密将8改为24    $td = mcrypt_module_open(MCRYPT_DES,'',MCRYPT_MODE_CBC,'');//3DES加密将MCRYPT_DES改为MCRYPT_3DES    if( $this->iv == '' )    {      $iv = @mcrypt_create_iv (mcrypt_enc_get_iv_size($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;  }}

$str = 'www.vevb.com';$des = new CryptDes();$mres = $des->encrypt($str); //加密echo $mres."<br/>";$jres = $des->decrypt($mres); //解密echo $jres."<br/>";