如何在 ASP.NET MVC 中获取客户端的 IP 地址？

Question

我是 ASP.NET MVC 堆栈的新手，我想知道简单的 Page 对象和 Request ServerVariables 对象发生了什么？

基本上，我想提取客户端 PC 的 IP 地址，但我不明白当前的 MVC 结构是如何改变这一切的。

据我所知，most of the variable objects has been replaced by the HttpRequest variants。

有人愿意分享一些资源吗？在 ASP.NET MVC 世界中确实有很多东西要学习。 :)

例如，我有一个带有这个当前函数的静态类。如何使用 ASP.NET MVC 获得相同的结果？

public static int getCountry(Page page)
{
    return getCountryFromIP(getIPAddress(page));
}

public static string getIPAddress(Page page)
{
    string szRemoteAddr = page.Request.ServerVariables["REMOTE_ADDR"];
    string szXForwardedFor = page.Request.ServerVariables["X_FORWARDED_FOR"];
    string szIP = "";

    if (szXForwardedFor == null)
    {
        szIP = szRemoteAddr;
    }
    else
    {
        szIP = szXForwardedFor;

        if (szIP.IndexOf(",") > 0)
        {
            string [] arIPs = szIP.Split(',');

            foreach (string item in arIPs)
            {
                if (!isPrivateIP(item))
                {
                    return item;
                }
            }
        }
    }
    return szIP;
}

我如何从控制器页面调用这个函数？

Answer 1

简单的答案是使用HttpRequest.UserHostAddress property。

示例：从控制器内部：

using System;
using System.Web.Mvc;

namespace Mvc.Controllers
{
    public class HomeController : ClientController
    {
        public ActionResult Index()
        {
            string ip = Request.UserHostAddress;

            ...
        }
    }
}

示例：从帮助程序类中：

using System.Web;

namespace Mvc.Helpers
{
    public static class HelperClass
    {
        public static string GetIPHelper()
        {
            string ip = HttpContext.Current.Request.UserHostAddress;
            ..
        }
    }
}

但是，如果请求已被一个或多个 proxy servers 传递，那么 HttpRequest.UserHostAddress property 返回的 IP 地址将是最后一个中继该请求的代理服务器的 IP 地址请求。

代理服务器可以使用 de facto 标准将客户端的 IP 地址放在X-Forwarded-For HTTP 标头中。除了不能保证请求具有 X-Forwarded-For 标头之外，也不能保证 X-Forwarded-For 不是 SPOOFED。

---

原答案

Request.UserHostAddress

上面的代码提供了客户端的 IP 地址，而无需查找集合。 Request 属性在控制器（或视图）中可用。因此，您可以传递一个 Request 对象来获得相同的结果，而不是将 Page 类传递给您的函数：

public static string getIPAddress(HttpRequestBase request)
{
    string szRemoteAddr = request.UserHostAddress;
    string szXForwardedFor = request.ServerVariables["X_FORWARDED_FOR"];
    string szIP = "";

    if (szXForwardedFor == null)
    {
        szIP = szRemoteAddr;
    }
    else
    {
        szIP = szXForwardedFor;
        if (szIP.IndexOf(",") > 0)
        {
            string [] arIPs = szIP.Split(',');

            foreach (string item in arIPs)
            {
                if (!isPrivateIP(item))
                {
                    return item;
                }
            }
        }
    }
    return szIP;
}

Answer 2

Request.ServerVariables["REMOTE_ADDR"] 应该可以工作 - 直接在视图中或在控制器操作方法体中（Request 是 MVC 中 Controller 类的属性，而不是 Page）。

它正在工作..但你必须在真实的​​ IIS 上发布，而不是虚拟的。

Answer 3

这里的很多代码都非常有用，但我出于自己的目的对其进行了清理并添加了一些测试。这是我最终得到的结果：

using System;
using System.Linq;
using System.Net;
using System.Web;

public class RequestHelpers
{
    public static string GetClientIpAddress(HttpRequestBase request)
    {
        try
        {
            var userHostAddress = request.UserHostAddress;

            // Attempt to parse.  If it fails, we catch below and return "0.0.0.0"
            // Could use TryParse instead, but I wanted to catch all exceptions
            IPAddress.Parse(userHostAddress);

            var xForwardedFor = request.ServerVariables["X_FORWARDED_FOR"];

            if (string.IsNullOrEmpty(xForwardedFor))
                return userHostAddress;

            // Get a list of public ip addresses in the X_FORWARDED_FOR variable
            var publicForwardingIps = xForwardedFor.Split(',').Where(ip => !IsPrivateIpAddress(ip)).ToList();

            // If we found any, return the last one, otherwise return the user host address
            return publicForwardingIps.Any() ? publicForwardingIps.Last() : userHostAddress;
        }
        catch (Exception)
        {
            // Always return all zeroes for any failure (my calling code expects it)
            return "0.0.0.0";
        }
    }

    private static bool IsPrivateIpAddress(string ipAddress)
    {
        // http://en.wikipedia.org/wiki/Private_network
        // Private IP Addresses are: 
        //  24-bit block: 10.0.0.0 through 10.255.255.255
        //  20-bit block: 172.16.0.0 through 172.31.255.255
        //  16-bit block: 192.168.0.0 through 192.168.255.255
        //  Link-local addresses: 169.254.0.0 through 169.254.255.255 (http://en.wikipedia.org/wiki/Link-local_address)

        var ip = IPAddress.Parse(ipAddress);
        var octets = ip.GetAddressBytes();

        var is24BitBlock = octets[0] == 10;
        if (is24BitBlock) return true; // Return to prevent further processing

        var is20BitBlock = octets[0] == 172 && octets[1] >= 16 && octets[1] <= 31;
        if (is20BitBlock) return true; // Return to prevent further processing

        var is16BitBlock = octets[0] == 192 && octets[1] == 168;
        if (is16BitBlock) return true; // Return to prevent further processing

        var isLinkLocalAddress = octets[0] == 169 && octets[1] == 254;
        return isLinkLocalAddress;
    }
}

这里有一些针对该代码的 NUnit 测试（我正在使用 Rhino Mocks 来模拟 HttpRequestBase，即下面的 M 调用）：

using System.Web;
using NUnit.Framework;
using Rhino.Mocks;
using Should;

[TestFixture]
public class HelpersTests : TestBase
{
    HttpRequestBase _httpRequest;

    private const string XForwardedFor = "X_FORWARDED_FOR";
    private const string MalformedIpAddress = "MALFORMED";
    private const string DefaultIpAddress = "0.0.0.0";
    private const string GoogleIpAddress = "74.125.224.224";
    private const string MicrosoftIpAddress = "65.55.58.201";
    private const string Private24Bit = "10.0.0.0";
    private const string Private20Bit = "172.16.0.0";
    private const string Private16Bit = "192.168.0.0";
    private const string PrivateLinkLocal = "169.254.0.0";

    [SetUp]
    public void Setup()
    {
        _httpRequest = M<HttpRequestBase>();
    }

    [TearDown]
    public void Teardown()
    {
        _httpRequest = null;
    }

    [Test]
    public void PublicIpAndNullXForwardedFor_Returns_CorrectIp()
    {
        // Arrange
        _httpRequest.Stub(x => x.UserHostAddress).Return(GoogleIpAddress);
        _httpRequest.Stub(x => x.ServerVariables[XForwardedFor]).Return(null);

        // Act
        var ip = RequestHelpers.GetClientIpAddress(_httpRequest);

        // Assert
        ip.ShouldEqual(GoogleIpAddress);
    }

    [Test]
    public void PublicIpAndEmptyXForwardedFor_Returns_CorrectIp()
    {
        // Arrange
        _httpRequest.Stub(x => x.UserHostAddress).Return(GoogleIpAddress);
        _httpRequest.Stub(x => x.ServerVariables[XForwardedFor]).Return(string.Empty);

        // Act
        var ip = RequestHelpers.GetClientIpAddress(_httpRequest);

        // Assert
        ip.ShouldEqual(GoogleIpAddress);
    }

    [Test]
    public void MalformedUserHostAddress_Returns_DefaultIpAddress()
    {
        // Arrange
        _httpRequest.Stub(x => x.UserHostAddress).Return(MalformedIpAddress);
        _httpRequest.Stub(x => x.ServerVariables[XForwardedFor]).Return(null);

        // Act
        var ip = RequestHelpers.GetClientIpAddress(_httpRequest);

        // Assert
        ip.ShouldEqual(DefaultIpAddress);
    }

    [Test]
    public void MalformedXForwardedFor_Returns_DefaultIpAddress()
    {
        // Arrange
        _httpRequest.Stub(x => x.UserHostAddress).Return(GoogleIpAddress);
        _httpRequest.Stub(x => x.ServerVariables[XForwardedFor]).Return(MalformedIpAddress);

        // Act
        var ip = RequestHelpers.GetClientIpAddress(_httpRequest);

        // Assert
        ip.ShouldEqual(DefaultIpAddress);
    }

    [Test]
    public void SingleValidPublicXForwardedFor_Returns_XForwardedFor()
    {
        // Arrange
        _httpRequest.Stub(x => x.UserHostAddress).Return(GoogleIpAddress);
        _httpRequest.Stub(x => x.ServerVariables[XForwardedFor]).Return(MicrosoftIpAddress);

        // Act
        var ip = RequestHelpers.GetClientIpAddress(_httpRequest);

        // Assert
        ip.ShouldEqual(MicrosoftIpAddress);
    }

    [Test]
    public void MultipleValidPublicXForwardedFor_Returns_LastXForwardedFor()
    {
        // Arrange
        _httpRequest.Stub(x => x.UserHostAddress).Return(GoogleIpAddress);
        _httpRequest.Stub(x => x.ServerVariables[XForwardedFor]).Return(GoogleIpAddress + "," + MicrosoftIpAddress);

        // Act
        var ip = RequestHelpers.GetClientIpAddress(_httpRequest);

        // Assert
        ip.ShouldEqual(MicrosoftIpAddress);
    }

    [Test]
    public void SinglePrivateXForwardedFor_Returns_UserHostAddress()
    {
        // Arrange
        _httpRequest.Stub(x => x.UserHostAddress).Return(GoogleIpAddress);
        _httpRequest.Stub(x => x.ServerVariables[XForwardedFor]).Return(Private24Bit);

        // Act
        var ip = RequestHelpers.GetClientIpAddress(_httpRequest);

        // Assert
        ip.ShouldEqual(GoogleIpAddress);
    }

    [Test]
    public void MultiplePrivateXForwardedFor_Returns_UserHostAddress()
    {
        // Arrange
        _httpRequest.Stub(x => x.UserHostAddress).Return(GoogleIpAddress);
        const string privateIpList = Private24Bit + "," + Private20Bit + "," + Private16Bit + "," + PrivateLinkLocal;
        _httpRequest.Stub(x => x.ServerVariables[XForwardedFor]).Return(privateIpList);

        // Act
        var ip = RequestHelpers.GetClientIpAddress(_httpRequest);

        // Assert
        ip.ShouldEqual(GoogleIpAddress);
    }

    [Test]
    public void MultiplePublicXForwardedForWithPrivateLast_Returns_LastPublic()
    {
        // Arrange
        _httpRequest.Stub(x => x.UserHostAddress).Return(GoogleIpAddress);
        const string privateIpList = Private24Bit + "," + Private20Bit + "," + MicrosoftIpAddress + "," + PrivateLinkLocal;
        _httpRequest.Stub(x => x.ServerVariables[XForwardedFor]).Return(privateIpList);

        // Act
        var ip = RequestHelpers.GetClientIpAddress(_httpRequest);

        // Assert
        ip.ShouldEqual(MicrosoftIpAddress);
    }
}

Answer 4

我在使用上述方法时遇到了问题，我需要来自控制器的 IP 地址。我最后使用了以下内容：

System.Web.HttpContext.Current.Request.UserHostAddress

Answer 5

在一个类中你可以这样称呼它：

public static string GetIPAddress(HttpRequestBase request) 
{
    string ip;
    try
    {
        ip = request.ServerVariables["HTTP_X_FORWARDED_FOR"];
        if (!string.IsNullOrEmpty(ip))
        {
            if (ip.IndexOf(",") > 0)
            {
                string[] ipRange = ip.Split(',');
                int le = ipRange.Length - 1;
                ip = ipRange[le];
            }
        } else
        {
            ip = request.UserHostAddress;
        }
    } catch { ip = null; }

    return ip; 
}

我在剃须刀应用程序中使用了它，效果很好。

Answer 6

我如何说明我的网站位于 Amazon AWS Elastic Load Balancer (ELB) 后面：

public class GetPublicIp {

    /// <summary>
    /// account for possbility of ELB sheilding the public IP address
    /// </summary>
    /// <returns></returns>
    public static string Execute() {
        try {
            Console.WriteLine(string.Join("|", new List<object> {
                    HttpContext.Current.Request.UserHostAddress,
                    HttpContext.Current.Request.Headers["X-Forwarded-For"],
                    HttpContext.Current.Request.Headers["REMOTE_ADDR"]
                })
            );

            var ip = HttpContext.Current.Request.UserHostAddress;
            if (HttpContext.Current.Request.Headers["X-Forwarded-For"] != null) {
                ip = HttpContext.Current.Request.Headers["X-Forwarded-For"];
                Console.WriteLine(ip + "|X-Forwarded-For");
            }
            else if (HttpContext.Current.Request.Headers["REMOTE_ADDR"] != null) {
                ip = HttpContext.Current.Request.Headers["REMOTE_ADDR"];
                Console.WriteLine(ip + "|REMOTE_ADDR");
            }
            return ip;
        }
        catch (Exception ex) {
            Console.Error.WriteLine(ex.Message);
        }
        return null;
    }
}