如何在 PHP 中获取客户端 IP 地址

Question

如何使用 PHP 获取客户端 IP 地址？

我想记录通过他/她的 IP 地址登录我网站的用户。

原文由 Anup Prakash 发布，翻译遵循 CC BY-SA 4.0 许可协议

Answer 1

我使用了其他答案之一，并添加了一些额外的东西，比如 CloudFlare 代理和 NGINX 代理检测。

 /**
 * Gets, validates and returns the connecting client's IP
 */
function getClientIP(){

    // Get real visitor IP behind CloudFlare network
    if (!empty($_SERVER["HTTP_CF_CONNECTING_IP"]) && validateIP($_SERVER['HTTP_CF_CONNECTING_IP'])) {
        return $_SERVER["HTTP_CF_CONNECTING_IP"];
    }

    // Get real visitor IP behind NGINX proxy - https://easyengine.io/tutorials/nginx/forwarding-visitors-real-ip/
    if (!empty($_SERVER["HTTP_X_REAL_IP"]) && validateIP($_SERVER['HTTP_X_REAL_IP'])) {
        return $_SERVER["HTTP_X_REAL_IP"];
    }

    // Check for shared Internet/ISP IP
    if (!empty($_SERVER['HTTP_CLIENT_IP']) && validateIP($_SERVER['HTTP_CLIENT_IP'])) {
        return $_SERVER['HTTP_CLIENT_IP'];
    }

    // Check for IP addresses passing through proxies
    if (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) {

        // Check if multiple IP addresses exist in var
        if (strpos($_SERVER['HTTP_X_FORWARDED_FOR'], ',') !== false) {
            $iplist = explode(',', $_SERVER['HTTP_X_FORWARDED_FOR']);
            foreach ($iplist as $ip) {
                if (validateIP($ip))
                    return $ip;
            }
        }
        else {
            if (validateIP($_SERVER['HTTP_X_FORWARDED_FOR']))
                return $_SERVER['HTTP_X_FORWARDED_FOR'];
        }
    }

    if (!empty($_SERVER['HTTP_X_FORWARDED']) && validateIP($_SERVER['HTTP_X_FORWARDED']))
        return $_SERVER['HTTP_X_FORWARDED'];

    if (!empty($_SERVER['HTTP_X_CLUSTER_CLIENT_IP']) && validateIP($_SERVER['HTTP_X_CLUSTER_CLIENT_IP']))
        return $_SERVER['HTTP_X_CLUSTER_CLIENT_IP'];

    if (!empty($_SERVER['HTTP_FORWARDED_FOR']) && validateIP($_SERVER['HTTP_FORWARDED_FOR']))
        return $_SERVER['HTTP_FORWARDED_FOR'];

    if (!empty($_SERVER['HTTP_FORWARDED']) && validateIP($_SERVER['HTTP_FORWARDED']))
        return $_SERVER['HTTP_FORWARDED'];

    // Return unreliable IP address since all else failed
    return $_SERVER['REMOTE_ADDR'];
}

/**
 * Ensures an IP address is both a valid IP address and does not fall within
 * a private network range.
 */
function validateIP($ip) {

    if (strtolower($ip) === 'unknown')
        return false;

    // Generate IPv4 network address
    $ip = ip2long($ip);

    // Do additional filtering on IP
    if(!filter_var($ip, FILTER_VALIDATE_IP))
        return false;

    // If the IP address is set and not equivalent to 255.255.255.255
    if ($ip !== false && $ip !== -1) {

        // Make sure to get unsigned long representation of IP address
        // due to discrepancies between 32 and 64 bit OSes and
        // signed numbers (ints default to signed in PHP)
        $ip = sprintf('%u', $ip);

        // Do private network range checking
        if ($ip >= 0 && $ip <= 50331647)
            return false;
        if ($ip >= 167772160 && $ip <= 184549375)
            return false;
        if ($ip >= 2130706432 && $ip <= 2147483647)
            return false;
        if ($ip >= 2851995648 && $ip <= 2852061183)
            return false;
        if ($ip >= 2886729728 && $ip <= 2887778303)
            return false;
        if ($ip >= 3221225984 && $ip <= 3221226239)
            return false;
        if ($ip >= 3232235520 && $ip <= 3232301055)
            return false;
        if ($ip >= 4294967040)
            return false;
    }
    return true;
}

我在生产节点中使用它并且效果很好。由于大部分代码都来自这里，我在 GNU @ https://github.com/d3vdigital/whatsmyip-node 下发布了一个节点

原文由 zac 发布，翻译遵循 CC BY-SA 4.0 许可协议