如何使用PHP获取客户端IP地址?

我想通过他/她的IP地址登录到我的网站的用户的记录。


当前回答

下面是一段代码,可以通过检查各种源来选择一个有效的IP。

首先,它检查'REMOTE_ADDR'是否是一个公共IP(并且不是您信任的反向代理之一),然后遍历其中一个HTTP头,直到找到一个公共IP并返回它。(PHP 5.2 +)

只要反向代理是可信的,或者服务器与客户端直接连接,它就应该是可靠的。

//Get client's IP or null if nothing looks valid
function ip_get($allow_private = false)
{
  //Place your trusted proxy server IPs here.
  $proxy_ip = ['127.0.0.1'];

  //The header to look for (Make sure to pick the one that your trusted reverse proxy is sending or else you can get spoofed)
  $header = 'HTTP_X_FORWARDED_FOR'; //HTTP_CLIENT_IP, HTTP_X_FORWARDED, HTTP_FORWARDED_FOR, HTTP_FORWARDED

  //If 'REMOTE_ADDR' seems to be a valid client IP, use it.
  if(ip_check($_SERVER['REMOTE_ADDR'], $allow_private, $proxy_ip)) return $_SERVER['REMOTE_ADDR'];

  if(isset($_SERVER[$header]))
  {
    //Split comma separated values [1] in the header and traverse the proxy chain backwards.
    //[1] https://en.wikipedia.org/wiki/X-Forwarded-For#Format
    $chain = array_reverse(preg_split('/\s*,\s*/', $_SERVER[$header]));
    foreach($chain as $ip) if(ip_check($ip, $allow_private, $proxy_ip)) return $ip;
  }

   return null;
}

//Check for valid IP. If 'allow_private' flag is set to truthy, it allows private IP ranges as valid client IP as well. (10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16)
//Pass your trusted reverse proxy IPs as $proxy_ip to exclude them from being valid.
function ip_check($ip, $allow_private = false, $proxy_ip = [])
{
  if(!is_string($ip) || is_array($proxy_ip) && in_array($ip, $proxy_ip)) return false;
  $filter_flag = FILTER_FLAG_NO_RES_RANGE;

  if(!$allow_private)
  {
    //Disallow loopback IP range which doesn't get filtered via 'FILTER_FLAG_NO_PRIV_RANGE' [1]
    //[1] https://www.php.net/manual/en/filter.filters.validate.php
    if(preg_match('/^127\.$/', $ip)) return false;
    $filter_flag |= FILTER_FLAG_NO_PRIV_RANGE;
  }

  return filter_var($ip, FILTER_VALIDATE_IP, $filter_flag) !== false;
}

其他回答

这里有一个简单的一行代码

$ip = $_SERVER['HTTP_X_FORWARDED_FOR']?: $_SERVER['HTTP_CLIENT_IP']?: $_SERVER['REMOTE_ADDR'];

编辑:

上面的代码可能会返回保留地址(如10.0.0.1),所有代理服务器的地址列表,等等。 要处理这些情况,请使用以下代码:

function valid_ip($ip) {
    // for list of reserved IP addresses, see https://en.wikipedia.org/wiki/Reserved_IP_addresses
    return $ip && substr($ip, 0, 4) != '127.' && substr($ip, 0, 4) != '127.' && substr($ip, 0, 3) != '10.' && substr($ip, 0, 2) != '0.' ? $ip : false;
}

function get_client_ip() {
    // using explode to get only client ip from list of forwarders. see https://en.wikipedia.org/wiki/X-Forwarded-For
    return
    @$_SERVER['HTTP_X_FORWARDED_FOR'] ? explode(',', $_SERVER['HTTP_X_FORWARDED_FOR'], 2)[0] :
    @$_SERVER['HTTP_CLIENT_IP'] ? explode(',', $_SERVER['HTTP_CLIENT_IP'], 2)[0] :
    valid_ip(@$_SERVER['REMOTE_ADDR']) ?:
    'UNKNOWN';
}

echo get_client_ip();

以下是我发现的最先进的方法,我在过去已经尝试过其他一些方法。确保获得访问者的IP地址是有效的(但请注意,任何黑客都很容易伪造IP地址)。

function get_ip_address() {

    // Check for shared Internet/ISP IP
    if (!empty($_SERVER['HTTP_CLIENT_IP']) && validate_ip($_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 $ip) {
                if (validate_ip($ip))
                    return $ip;
            }
        }
        else {
            if (validate_ip($_SERVER['HTTP_X_FORWARDED_FOR']))
                return $_SERVER['HTTP_X_FORWARDED_FOR'];
        }
    }
    if (!empty($_SERVER['HTTP_X_FORWARDED']) && validate_ip($_SERVER['HTTP_X_FORWARDED']))
        return $_SERVER['HTTP_X_FORWARDED'];
    if (!empty($_SERVER['HTTP_X_CLUSTER_CLIENT_IP']) && validate_ip($_SERVER['HTTP_X_CLUSTER_CLIENT_IP']))
        return $_SERVER['HTTP_X_CLUSTER_CLIENT_IP'];
    if (!empty($_SERVER['HTTP_FORWARDED_FOR']) && validate_ip($_SERVER['HTTP_FORWARDED_FOR']))
        return $_SERVER['HTTP_FORWARDED_FOR'];
    if (!empty($_SERVER['HTTP_FORWARDED']) && validate_ip($_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 validate_ip($ip) {

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

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

    // 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;
}

如果您不喜欢使用If -else/switch语句,那么下面的解决方案适合您。

function get_client_ip()
{
    $fields = array(
        'HTTP_CF_CONNECTING_IP',
        'HTTP_X_SUCURI_CLIENTIP',
        'HTTP_CLIENT_IP',
        'HTTP_X_FORWARDED_FOR',
        'HTTP_X_FORWARDED',
        'HTTP_FORWARDED_FOR',
        'HTTP_FORWARDED',
        'REMOTE_ADDR',
        // more custom fields
    );

    foreach ($fields as $ip_field) {
        if (!empty($_SERVER[$ip_field])) {
            return $_SERVER[$ip_field];
        }
    }

    return null;
}

下面是一个很好的获取用户IP地址的干净代码示例。

$ip = $_SERVER['HTTP_CLIENT_IP'] 
   ? $_SERVER['HTTP_CLIENT_IP'] 
   : ($_SERVER['HTTP_X_FORWARDED_FOR'] 
        ? $_SERVER['HTTP_X_FORWARDED_FOR'] 
        : $_SERVER['REMOTE_ADDR']);

下面是一个使用elvis操作符的简短版本:

$_SERVER['HTTP_CLIENT_IP'] 
   ? : ($_SERVER['HTTP_X_FORWARDED_FOR'] 
   ? : $_SERVER['REMOTE_ADDR']);

下面是一个使用isset删除通知的版本(谢谢你,@shasi kanth):

$ip = isset($_SERVER['HTTP_CLIENT_IP']) 
    ? $_SERVER['HTTP_CLIENT_IP'] 
    : (isset($_SERVER['HTTP_X_FORWARDED_FOR']) 
      ? $_SERVER['HTTP_X_FORWARDED_FOR'] 
      : $_SERVER['REMOTE_ADDR']);

下面是一段代码,可以通过检查各种源来选择一个有效的IP。

首先,它检查'REMOTE_ADDR'是否是一个公共IP(并且不是您信任的反向代理之一),然后遍历其中一个HTTP头,直到找到一个公共IP并返回它。(PHP 5.2 +)

只要反向代理是可信的,或者服务器与客户端直接连接,它就应该是可靠的。

//Get client's IP or null if nothing looks valid
function ip_get($allow_private = false)
{
  //Place your trusted proxy server IPs here.
  $proxy_ip = ['127.0.0.1'];

  //The header to look for (Make sure to pick the one that your trusted reverse proxy is sending or else you can get spoofed)
  $header = 'HTTP_X_FORWARDED_FOR'; //HTTP_CLIENT_IP, HTTP_X_FORWARDED, HTTP_FORWARDED_FOR, HTTP_FORWARDED

  //If 'REMOTE_ADDR' seems to be a valid client IP, use it.
  if(ip_check($_SERVER['REMOTE_ADDR'], $allow_private, $proxy_ip)) return $_SERVER['REMOTE_ADDR'];

  if(isset($_SERVER[$header]))
  {
    //Split comma separated values [1] in the header and traverse the proxy chain backwards.
    //[1] https://en.wikipedia.org/wiki/X-Forwarded-For#Format
    $chain = array_reverse(preg_split('/\s*,\s*/', $_SERVER[$header]));
    foreach($chain as $ip) if(ip_check($ip, $allow_private, $proxy_ip)) return $ip;
  }

   return null;
}

//Check for valid IP. If 'allow_private' flag is set to truthy, it allows private IP ranges as valid client IP as well. (10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16)
//Pass your trusted reverse proxy IPs as $proxy_ip to exclude them from being valid.
function ip_check($ip, $allow_private = false, $proxy_ip = [])
{
  if(!is_string($ip) || is_array($proxy_ip) && in_array($ip, $proxy_ip)) return false;
  $filter_flag = FILTER_FLAG_NO_RES_RANGE;

  if(!$allow_private)
  {
    //Disallow loopback IP range which doesn't get filtered via 'FILTER_FLAG_NO_PRIV_RANGE' [1]
    //[1] https://www.php.net/manual/en/filter.filters.validate.php
    if(preg_match('/^127\.$/', $ip)) return false;
    $filter_flag |= FILTER_FLAG_NO_PRIV_RANGE;
  }

  return filter_var($ip, FILTER_VALIDATE_IP, $filter_flag) !== false;
}