字符串加密解密算法

 php5.5中有更为可靠和方便的加密方式。喜欢钻研的朋友可以了解一下：

 password_hash()

http://www.php.net/manual/zh/function.password-hash.php

基于mcrypt扩展，按位异或总结的两个字符串加密解密算法

<?<span>php
</span><span>/*</span><span>*
 * @info 字符串加密解密算法一,利用mcrypt扩展
 * @param string $string 待处理字符串
 *        $action ENCODE,加密 | DECODE，解密
 * @return string $returnstr
 * @date 2014/4/22
 * @author tonglei
 </span><span>*/</span>

<span>function</span> mcrypt_handle_string(<span>$string</span>, <span>$action</span> = 'ENCODE'<span>)
{
        </span>!<span>is_array</span>(<span>$string</span>) or <span>exit</span><span>;
        </span><span>$action</span> == 'DECODE' && <span>$string</span> = <span>base64_decode</span>(<span>$string</span><span>);
        </span><span>$key</span> = "123456"; <span>//</span><span>key可自定义或在配置文件中获取</span>
        <span>$mcryptAlgorithm</span> = MCRYPT_DES; <span>//</span><span>选择一种加密算法</span>
        <span>$mcryptMode</span> = MCRYPT_MODE_ECB; <span>//</span><span>选择一种加密模式</span>
        <span>$mcryptIv</span> = mcrypt_create_iv(mcrypt_get_iv_size(<span>$mcryptAlgorithm</span>, <span>$mcryptMode</span>),<span>
                MCRYPT_RAND); </span><span>//</span><span>创建初始化向量</span>

        <span>$returnstr</span> = <span>base64_encode</span>(mcrypt_encrypt(<span>$mcryptAlgorithm</span>, <span>$key</span>, <span>$string</span>, <span>$mcryptMode</span>,
                <span>$mcryptIv</span><span>));
        </span><span>if</span>('DECODE' == <span>$action</span><span>)
        {
                </span><span>$returnstr</span> = mcrypt_decrypt(<span>$mcryptAlgorithm</span>, <span>$key</span>, <span>$string</span>, <span>$mcryptMode</span>, <span>$mcryptIv</span><span>);
        }
        </span><span>return</span> <span>$returnstr</span><span>;

}</span>

<?<span>php
</span><span>/*</span><span>*
 *
 * @info 字符串加密解密算法二 利用按位异或
 * @param string $string 待处理字符串
 * @param $action ENCODE 加密 | DECODE 解密
 * @return string
 </span><span>*/</span>
<span>function</span> StrCode(<span>$string</span>, <span>$action</span> = 'ENCODE'<span>)
{
        </span><span>$action</span> != 'ENCODE' && <span>$string</span> = <span>base64_decode</span>(<span>$string</span><span>);
        </span><span>$code</span> = ''<span>;
        </span><span>$key</span> = <span>substr</span>(<span>md5</span>(<span>$GLOBALS</span>['pwServer']['HTTP_USER_AGENT'] . <span>$GLOBALS</span>['db_hash']),
                8, 18<span>);
        </span><span>$keyLen</span> = <span>strlen</span>(<span>$key</span><span>);
        </span><span>$strLen</span> = <span>strlen</span>(<span>$string</span><span>);
        </span><span>for</span> (<span>$i</span> = 0; <span>$i</span> < <span>$strLen</span>; <span>$i</span>++<span>)
        {
                </span><span>$k</span> = <span>$i</span> % <span>$keyLen</span><span>;
                </span><span>$code</span> .= <span>$string</span>[<span>$i</span>] ^ <span>$key</span>[<span>$k</span><span>];
        }
        </span><span>return</span> (<span>$action</span> != 'DECODE' ? <span>base64_encode</span>(<span>$code</span>) : <span>$code</span><span>);
}</span>