cloudflare email 邮箱混淆/加密/解密 PHP 源码版

在某个网站上看到一串 email 的混淆字符串，通常，这些地址会被标记为'email protected'或类似的占位符。搜了一下，竟然是 cloudflare 家的。

混淆

private function encodeEmail($email, $key=0)
{
    $chars = str_split($email);
    $string = '';
    $key = $key ? $key : rand(10, 99);
    foreach ($chars as $value) {
        $string .= sprintf("%02s", dechex(ord($value)^$key));
    }
    return dechex($key).$string;
}

还原

private function decodeEmail($encode)
{
    $k = hexdec(substr($encode,0,2));
    for($i=2, $m=''; $i < strlen($encode) - 1; $i += 2){
        $m.=chr(hexdec(substr($encode, $i, 2))^$k);
    }
    return $m;
}