- 为了增加数据的安全性
- 避免相同字符多次加密得到结果是一致的
- 可以设置密文有效期 加密方式:Mcrypt::encode(Str, n); 解密方式: Mcrypt::decode(Str, n);
require("Mcrypt.class.php") ;
$code = Mcrypt::encode('sajkfcasjcla','7580');
echo "code-".$code;
$code_ans = Mcrypt::decode("$code",'7580');
echo "answer-".$code_ans;
Mcrypt.class.php
代码语言:javascript复制/*
* 字符串加解密类;
* 一次一密;且定时解密有效
* 可用于加密&动态key生成
*/
class Mcrypt{
public $default_key = 'a!takA:dlmcldEv,e';
/**
* 字符加密,一次一密,可定时解密有效
* @param string $string 原文
* @param string $key 密钥
* @param int $expiry 密文有效期,单位s,0 为永久有效
* @return string 加密后的内容
*/
public static function encode($string,$key = '', $expiry = 0){
$ckeyLength = 4;
$key = md5($key ? $key : $this->default_key); //解密密匙
$keya = md5(substr($key, 0, 16)); //做数据完整性验证
$keyb = md5(substr($key, 16, 16)); //用于变化生成的密文 (初始化向量IV)
$keyc = substr(md5(microtime()), - $ckeyLength);
$cryptkey = $keya . md5($keya . $keyc);
$keyLength = strlen($cryptkey);
$string = sprintf('0d', $expiry ? $expiry time() : 0).substr(md5($string . $keyb), 0, 16) . $string;
$stringLength = strlen($string);
$rndkey = array();
for($i = 0; $i <= 255; $i ) {
$rndkey[$i] = ord($cryptkey[$i % $keyLength]);
}
$box = range(0, 255);
// 打乱密匙簿,增加随机性
for($j = $i = 0; $i < 256; $i ) {
$j = ($j $box[$i] $rndkey[$i]) % 256;
$tmp = $box[$i];
$box[$i] = $box[$j];
$box[$j] = $tmp;
}
// 加解密,从密匙簿得出密匙进行异或,再转成字符
$result = '';
for($a = $j = $i = 0; $i < $stringLength; $i ) {
$a = ($a 1) % 256;
$j = ($j $box[$a]) % 256;
$tmp = $box[$a];
$box[$a] = $box[$j];
$box[$j] = $tmp;
$result .= chr(ord($string[$i]) ^ ($box[($box[$a] $box[$j]) % 256]));
}
$result = $keyc . str_replace('=', '', base64_encode($result));
$result = str_replace(array(' ', '/', '='),array('-', '_', '.'), $result);
return $result;
}
/**
* 字符解密,一次一密,可定时解密有效
* @param string $string 密文
* @param string $key 解密密钥
* @return string 解密后的内容
*/
public static function decode($string,$key = '') {
$string = str_replace(array('-', '_', '.'),array(' ', '/', '='), $string);
$ckeyLength = 4;
$key = md5($key ? $key : $this->default_key); //解密密匙
$keya = md5(substr($key, 0, 16)); //做数据完整性验证
$keyb = md5(substr($key, 16, 16)); //用于变化生成的密文 (初始化向量IV)
$keyc = substr($string, 0, $ckeyLength);
$cryptkey = $keya . md5($keya . $keyc);
$keyLength = strlen($cryptkey);
$string = base64_decode(substr($string, $ckeyLength));
$stringLength = strlen($string);
$rndkey = array();
for($i = 0; $i <= 255; $i ) {
$rndkey[$i] = ord($cryptkey[$i % $keyLength]);
}
$box = range(0, 255);
// 打乱密匙簿,增加随机性
for($j = $i = 0; $i < 256; $i ) {
$j = ($j $box[$i] $rndkey[$i]) % 256;
$tmp = $box[$i];
$box[$i] = $box[$j];
$box[$j] = $tmp;
}
// 加解密,从密匙簿得出密匙进行异或,再转成字符
$result = '';
for($a = $j = $i = 0; $i < $stringLength; $i ) {
$a = ($a 1) % 256;
$j = ($j $box[$a]) % 256;
$tmp = $box[$a];
$box[$a] = $box[$j];
$box[$j] = $tmp;
$result .= chr(ord($string[$i]) ^ ($box[($box[$a] $box[$j]) % 256]));
}
if ((substr($result, 0, 10) == 0 || substr($result, 0, 10) - time() > 0)
&& substr($result, 10, 16) == substr(md5(substr($result, 26) . $keyb), 0, 16)
) {
return substr($result, 26);
} else {
return '';
}
}
}