经典PHP加密解密函数Authcode()修复版代码 |
|
本文标签:PHP加密解密,Authcode Authcode这个函数很多人都使用,这函数来自Discuz程序,用于加密解密字符串,可以设置钥匙(key)和过期时间,在很多时候都用得着 。原版的函数代码可能会生成+、/、&这样的字符,导致通过URL传值取回时被转义,导致无法解密 。火端网络稍加修改,把这几个字符替换成其它字符,解密时再替换回去,这样就完美了! 代码如下:
function authcode($string, $operation = DECODE, $key = , $expiry = 0){
if($operation == DECODE) {
$string = str_replace([a],+,$string);
$string = str_replace([b],&,$string);
$string = str_replace([c],/,$string);
}
$ckey_length = 4;
$key = md5($key ? $key : livcmsencryption );
$keya = md5(substr($key, 0, 16));
$keyb = md5(substr($key, 16, 16));
$keyc = $ckey_length ? ($operation == DECODE ? substr($string, 0, $ckey_length): substr(md5(microtime()), -$ckey_length)) : ;
$cryptkey = $keya.md5($keya.$keyc);
$key_length = strlen($cryptkey);
$string = $operation == DECODE ? base64_decode(substr($string, $ckey_length)) : sprintf(%010d, $expiry ? $expiry + time() : 0).substr(md5($string.$keyb), 0, 16).$string;
$string_length = strlen($string);
$result = ;
$box = range(0, 255);
$rndkey = array();
for($i = 0; $i <= 255; $i++) {
$rndkey[$i] = ord($cryptkey[$i % $key_length]);
}
for($j = $i = 0; $i < 256; $i++) {
$j = ($j + $box[$i] + $rndkey[$i]) % 256;
$tmp = $box[$i];
$box[$i] = $box[$j];
$box[$j] = $tmp;
}
for($a = $j = $i = 0; $i < $string_length; $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($operation == DECODE) {
if((substr($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 ;
}
} else {
$ustr = $keyc.str_replace(=, , base64_encode($result));
$ustr = str_replace(+,[a],$ustr);
$ustr = str_replace(&,[b],$ustr);
$ustr = str_replace(/,[c],$ustr);
return $ustr;
}
}
|