php中加密解密DES类的简单使用方法示例

本文实例讲述了php中加密解密des类的简单使用方法。分享给大家供大家参考，具体如下：

在平时的开发工作中，我们经常会对关键字符进行加密，可能为了安全也可能为了规范，所以要正确使用des加密解密

代码1:

class des

{

var $key; // 密钥

var $iv; // 偏移量

function __construct( $key, $iv=0 ) {

$this->key = $key;

if( $iv == 0 ) {

$this->iv = $key;

} else {

$this->iv = $iv;

// 创建初始向量, 并且检测密钥长度, windows 平台请使用 mcrypt_rand

// mcrypt_create_iv ( mcrypt_get_block_size (mcrypt_des, mcrypt_mode_cbc), mcrypt_dev_random );

}

function encrypt($str) {

//加密，返回大写十六进制字符串

$size = mcrypt_get_block_size ( mcrypt_des, mcrypt_mode_cbc );

$str = $this->pkcs5pad ( $str, $size );

// bin2hex 把 ascii 字符的字符串转换为十六进制值

return strtoupper( bin2hex( mcrypt_cbc(mcrypt_des, $this->key, $str, mcrypt_encrypt, $this->iv ) ) );

}

function decrypt($str) {

//解密

$strbin = $this->hex2bin( strtolower( $str ) );

$str = mcrypt_cbc( mcrypt_des, $this->key, $strbin, mcrypt_decrypt, $this->iv );

$str = $this->pkcs5unpad( $str );

return $str;

}

function hex2bin($hexdata) {

$bindata = "";

for($i = 0; $i < strlen ( $hexdata ); $i += 2) {

$bindata .= chr ( hexdec ( substr ( $hexdata, $i, 2 ) ) );

}

return $bindata;

}

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 );

}

deprecated: methods with the same name as their class will not be constructors in a future version of php; des5 has a deprecated constructor in d:\\phpstudy_pro\\www\\des\\des5.php on line 2

fatal error: uncaught error: call to undefined function mcrypt_get_block_size() in d:\\phpstudy_pro\\www\\des\\des5.php:19 stack trace: #0 d:\\phpstudy_pro\\www\\des\\1.php(10): des5->encrypt('podsmia') #1 {main} thrown in d:\\phpstudy_pro\\www\\des\\des5.php on line 19