[PHP]代码
<?php //blog.qita.infunction passport_encrypt($txt, $key) { srand((double)microtime() * 1000000); $encrypt_key = md5(rand(0, 32000)); $ctr = 0; $tmp = ‘‘; for($i = 0;$i < strlen($txt); $i++) { $ctr = $ctr == strlen($encrypt_key) ? 0 : $ctr; $tmp .= $encrypt_key[$ctr].($txt[$i] ^ $encrypt_key[$ctr++]); } return base64_encode(passport_key($tmp, $key)); }function passport_decrypt($txt, $key) { $txt = passport_key(base64_decode($txt), $key); $tmp = ‘‘; for($i = 0;$i < strlen($txt); $i++) { $md5 = $txt[$i]; $tmp .= $txt[++$i] ^ $md5; } return $tmp; }function passport_key($txt, $encrypt_key) { $encrypt_key = md5($encrypt_key); $ctr = 0; $tmp = ‘‘; for($i = 0; $i < strlen($txt); $i++) { $ctr = $ctr == strlen($encrypt_key) ? 0 : $ctr; $tmp .= $txt[$i] ^ $encrypt_key[$ctr++]; } return $tmp; } ?>PHP加密解密函数
原文地址：http://www.cnblogs.com/ghjbk/p/7519827.html