We have Request.UserHostAddress to get the IP address in ASP.NET, but this is usually the user's ISP's IP address, not exactly the user's machine IP address who for example clicked a link. How can I get the real IP Address?
For example, in a Stack Overflow user profile it is: "Last account activity: 4 hours ago from 86.123.127.8", but my machine IP address is a bit different. How does Stack Overflow get this address?
In some web systems there is an IP address check for some purposes. For example, with a certain IP address, for every 24 hours can the user just have only 5 clicks on download links? This IP address should be unique, not for an ISP that has a huge range of clients or Internet users.
Did I understand well?
Often you will want to know the IP address of someone visiting your website. While ASP.NET has several ways to do this one of the best ways we've seen is by using the "HTTP_X_FORWARDED_FOR" of the ServerVariables collection.
Here's why...
Sometimes your visitors are behind either a proxy server or a router and the standard Request.UserHostAddress only captures the IP address of the proxy server or router. When this is the case the user's IP address is then stored in the server variable ("HTTP_X_FORWARDED_FOR").
So what we want to do is first check "HTTP_X_FORWARDED_FOR" and if that is empty we then simply return ServerVariables("REMOTE_ADDR").
While this method is not foolproof, it can lead to better results. Below is the ASP.NET code in VB.NET, taken from James Crowley's blog post "Gotcha: HTTP_X_FORWARDED_FOR returns multiple IP addresses"
C#
protected string GetIPAddress()
{
System.Web.HttpContext context = System.Web.HttpContext.Current;
string ipAddress = context.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
if (!string.IsNullOrEmpty(ipAddress))
{
string[] addresses = ipAddress.Split(',');
if (addresses.Length != 0)
{
return addresses[0];
}
}
return context.Request.ServerVariables["REMOTE_ADDR"];
}
VB.NET
Public Shared Function GetIPAddress() As String
Dim context As System.Web.HttpContext = System.Web.HttpContext.Current
Dim sIPAddress As String = context.Request.ServerVariables("HTTP_X_FORWARDED_FOR")
If String.IsNullOrEmpty(sIPAddress) Then
Return context.Request.ServerVariables("REMOTE_ADDR")
Else
Dim ipArray As String() = sIPAddress.Split(New [Char]() {","c})
Return ipArray(0)
End If
End Function
As others have said you can't do what you are asking. If you describe the problem you are trying to solve maybe someone can help?
E.g.
are you trying to uniquely identify your users?
Could you use a cookie, or the session ID perhaps instead of the IP address?
Edit The address you see on the server shouldn't be the ISP's address, as you say that would be a huge range. The address for a home user on broadband will be the address at their router, so every device inside the house will appear on the outside to be the same, but the router uses NAT to ensure that traffic is routed to each device correctly. For users accessing from an office environment the address may well be the same for all users. Sites that use IP address for ID run the risk of getting it very wrong - the examples you give are good ones and they often fail. For example my office is in the UK, the breakout point (where I "appear" to be on the internet) is in another country where our main IT facility is, so from my office my IP address appears to be not in the UK. For this reason I can't access UK only web content, such as the BBC iPlayer). At any given time there would be hundreds, or even thousands, of people at my company who appear to be accessing the web from the same IP address.
When you are writing server code you can never be sure what the IP address you see is referring to. Some users like it this way. Some people deliberately use a proxy or VPN to further confound you.
When you say your machine address is different to the IP address shown on StackOverflow, how are you finding out your machine address? If you are just looking locally using ipconfig or something like that I would expect it to be different for the reasons I outlined above. If you want to double check what the outside world thinks have a look at whatismyipaddress.com/.
This Wikipedia link on NAT will provide you some background on this.
UPDATE:
Thanks to Bruno Lopes. If several ip addresses could come then need to use this method:
private string GetUserIP()
{
string ipList = Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
if (!string.IsNullOrEmpty(ipList))
{
return ipList.Split(',')[0];
}
return Request.ServerVariables["REMOTE_ADDR"];
}
If is c# see this way, is very simple
string clientIp = (Request.ServerVariables["HTTP_X_FORWARDED_FOR"] ??
Request.ServerVariables["REMOTE_ADDR"]).Split(',')[0].Trim();
What else do you consider the user IP address? If you want the IP address of the network adapter, I'm afraid there's no possible way to do it in a Web app. If your user is behind NAT or other stuff, you can't get the IP either.
Update: While there are Web sites that use IP to limit the user (like rapidshare), they don't work correctly in NAT environments.
I think I should share my experience with you all. Well I see in some situations REMOTE_ADDR will NOT get you what you are looking for. For instance, if you have a Load Balancer behind the scene and if you are trying to get the Client's IP then you will be in trouble. I checked it with my IP masking software plus I also checked with my colleagues being in different continents. So here is my solution.
When I want to know the IP of a client, I try to pick every possible evidence so I could determine if they are unique:
Here I found another sever-var that could help you all if you want to get exact IP of the client side. so I am using : HTTP_X_CLUSTER_CLIENT_IP
HTTP_X_CLUSTER_CLIENT_IP always gets you the exact IP of the client. In any case if its not giving you the value, you should then look for HTTP_X_FORWARDED_FOR as it is the second best candidate to get you the client IP and then the REMOTE_ADDR var which may or may not return you the IP but to me having all these three is what I find the best thing to monitor them.
I hope this helps some guys.
You can use:
System.Net.Dns.GetHostEntry(System.Net.Dns.GetHostName()).AddressList.GetValue(0).ToString();
All of the responses so far take into account the non-standardized, but very common, X-Forwarded-For header. There is a standardized Forwarded header which is a little more difficult to parse out. Some examples are as follows:
Forwarded: for="_gazonk"
Forwarded: For="[2001:db8:cafe::17]:4711"
Forwarded: for=192.0.2.60;proto=http;by=203.0.113.43
Forwarded: for=192.0.2.43, for=198.51.100.17
I have written a class that takes both of these headers into account when determining a client's IP address.
using System;
using System.Web;
namespace Util
{
public static class IP
{
public static string GetIPAddress()
{
return GetIPAddress(new HttpRequestWrapper(HttpContext.Current.Request));
}
internal static string GetIPAddress(HttpRequestBase request)
{
// handle standardized 'Forwarded' header
string forwarded = request.Headers["Forwarded"];
if (!String.IsNullOrEmpty(forwarded))
{
foreach (string segment in forwarded.Split(',')[0].Split(';'))
{
string[] pair = segment.Trim().Split('=');
if (pair.Length == 2 && pair[0].Equals("for", StringComparison.OrdinalIgnoreCase))
{
string ip = pair[1].Trim('"');
// IPv6 addresses are always enclosed in square brackets
int left = ip.IndexOf('['), right = ip.IndexOf(']');
if (left == 0 && right > 0)
{
return ip.Substring(1, right - 1);
}
// strip port of IPv4 addresses
int colon = ip.IndexOf(':');
if (colon != -1)
{
return ip.Substring(0, colon);
}
// this will return IPv4, "unknown", and obfuscated addresses
return ip;
}
}
}
// handle non-standardized 'X-Forwarded-For' header
string xForwardedFor = request.Headers["X-Forwarded-For"];
if (!String.IsNullOrEmpty(xForwardedFor))
{
return xForwardedFor.Split(',')[0];
}
return request.UserHostAddress;
}
}
}
Below are some unit tests that I used to validate my solution:
using System.Collections.Specialized;
using System.Web;
using Microsoft.VisualStudio.TestTools.UnitTesting;
namespace UtilTests
{
[TestClass]
public class IPTests
{
[TestMethod]
public void TestForwardedObfuscated()
{
var request = new HttpRequestMock("for=\"_gazonk\"");
Assert.AreEqual("_gazonk", Util.IP.GetIPAddress(request));
}
[TestMethod]
public void TestForwardedIPv6()
{
var request = new HttpRequestMock("For=\"[2001:db8:cafe::17]:4711\"");
Assert.AreEqual("2001:db8:cafe::17", Util.IP.GetIPAddress(request));
}
[TestMethod]
public void TestForwardedIPv4()
{
var request = new HttpRequestMock("for=192.0.2.60;proto=http;by=203.0.113.43");
Assert.AreEqual("192.0.2.60", Util.IP.GetIPAddress(request));
}
[TestMethod]
public void TestForwardedIPv4WithPort()
{
var request = new HttpRequestMock("for=192.0.2.60:443;proto=http;by=203.0.113.43");
Assert.AreEqual("192.0.2.60", Util.IP.GetIPAddress(request));
}
[TestMethod]
public void TestForwardedMultiple()
{
var request = new HttpRequestMock("for=192.0.2.43, for=198.51.100.17");
Assert.AreEqual("192.0.2.43", Util.IP.GetIPAddress(request));
}
}
public class HttpRequestMock : HttpRequestBase
{
private NameValueCollection headers = new NameValueCollection();
public HttpRequestMock(string forwarded)
{
headers["Forwarded"] = forwarded;
}
public override NameValueCollection Headers
{
get { return this.headers; }
}
}
}
IP addresses are part of the Network layer in the "seven-layer stack". The Network layer can do whatever it wants to do with the IP address. That's what happens with a proxy server, NAT, relay, or whatever.
The Application layer should not depend on the IP address in any way. In particular, an IP Address is not meant to be an identifier of anything other than the idenfitier of one end of a network connection. As soon as a connection is closed, you should expect the IP address (of the same user) to change.
If you are using CloudFlare,
you can try this Extension Method:
public static class IPhelper
{
public static string GetIPAddress(this HttpRequest Request)
{
if (Request.Headers["CF-CONNECTING-IP"] != null) return Request.Headers["CF-CONNECTING-IP"].ToString();
if (Request.ServerVariables["HTTP_X_FORWARDED_FOR"] != null) return Request.ServerVariables["HTTP_X_FORWARDED_FOR"].ToString();
return Request.UserHostAddress;
}
}
then
string IPAddress = Request.GetIPAddress();
string IP = HttpContext.Current.Request.Params["HTTP_CLIENT_IP"] ?? HttpContext.Current.Request.UserHostAddress;
What you can do is store the router IP of your user and also the forwarded IP and try to make it reliable using both the IPs [External Public and Internal Private]. But again after some days client may be assigned new internal IP from router but it will be more reliable.
Combining the answers from #Tony and #mangokun, I have created the following extension method:
public static class RequestExtensions
{
public static string GetIPAddress(this HttpRequest Request)
{
if (Request.Headers["CF-CONNECTING-IP"] != null) return Request.Headers["CF-CONNECTING-IP"].ToString();
if (Request.ServerVariables["HTTP_X_FORWARDED_FOR"] != null)
{
string ipAddress = Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
if (!string.IsNullOrEmpty(ipAddress))
{
string[] addresses = ipAddress.Split(',');
if (addresses.Length != 0)
{
return addresses[0];
}
}
}
return Request.UserHostAddress;
}
}
public static class Utility
{
public static string GetClientIP(this System.Web.UI.Page page)
{
string _ipList = page.Request.Headers["CF-CONNECTING-IP"].ToString();
if (!string.IsNullOrWhiteSpace(_ipList))
{
return _ipList.Split(',')[0].Trim();
}
else
{
_ipList = page.Request.ServerVariables["HTTP_X_CLUSTER_CLIENT_IP"];
if (!string.IsNullOrWhiteSpace(_ipList))
{
return _ipList.Split(',')[0].Trim();
}
else
{
_ipList = page.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
if (!string.IsNullOrWhiteSpace(_ipList))
{
return _ipList.Split(',')[0].Trim();
}
else
{
return page.Request.ServerVariables["REMOTE_ADDR"].ToString().Trim();
}
}
}
}
}
Use;
string _ip = this.GetClientIP();
use in ashx file
public string getIP(HttpContext c)
{
string ips = c.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
if (!string.IsNullOrEmpty(ips))
{
return ips.Split(',')[0];
}
return c.Request.ServerVariables["REMOTE_ADDR"];
}
In NuGet package install Microsoft.AspNetCore.HttpOverrides
Then try:
public class ClientDeviceInfo
{
private readonly IHttpContextAccessor httpAccessor;
public ClientDeviceInfo(IHttpContextAccessor httpAccessor)
{
this.httpAccessor = httpAccessor;
}
public string GetClientLocalIpAddress()
{
return httpAccessor.HttpContext.Connection.LocalIpAddress.ToString();
}
public string GetClientRemoteIpAddress()
{
return httpAccessor.HttpContext.Connection.RemoteIpAddress.ToString();
}
public string GetClientLocalPort()
{
return httpAccessor.HttpContext.Connection.LocalPort.ToString();
}
public string GetClientRemotePort()
{
return httpAccessor.HttpContext.Connection.RemotePort.ToString();
}
}
Its easy.Try it:
var remoteIpAddress = Request.HttpContext.Connection.RemoteIpAddress;
just it :))
use this
Dns.GetHostEntry(Dns.GetHostName())
Hello guys Most of the codes you will find will return you server ip address not client ip address .however this code returns correct client ip address.Give it a try.
For More info just check this
https://www.youtube.com/watch?v=Nkf37DsxYjI
for getting your local ip address using javascript you can use
put this code inside your script tag
<script>
var RTCPeerConnection = /*window.RTCPeerConnection ||*/
window.webkitRTCPeerConnection || window.mozRTCPeerConnection;
if (RTCPeerConnection) (function () {
var rtc = new RTCPeerConnection({ iceServers: [] });
if (1 || window.mozRTCPeerConnection) {
rtc.createDataChannel('', { reliable: false });
};
rtc.onicecandidate = function (evt) {
if (evt.candidate)
grepSDP("a=" + evt.candidate.candidate);
};
rtc.createOffer(function (offerDesc) {
grepSDP(offerDesc.sdp);
rtc.setLocalDescription(offerDesc);
}, function (e) { console.warn("offer failed", e); });
var addrs = Object.create(null);
addrs["0.0.0.0"] = false;
function updateDisplay(newAddr) {
if (newAddr in addrs) return;
else addrs[newAddr] = true;
var displayAddrs = Object.keys(addrs).filter(function
(k) { return addrs[k]; });
document.getElementById('list').textContent =
displayAddrs.join(" or perhaps ") || "n/a";
}
function grepSDP(sdp) {
var hosts = [];
sdp.split('\r\n').forEach(function (line) {
if (~line.indexOf("a=candidate")) {
var parts = line.split(' '),
addr = parts[4],
type = parts[7];
if (type === 'host') updateDisplay(addr);
} else if (~line.indexOf("c=")) {
var parts = line.split(' '),
addr = parts[2];
updateDisplay(addr);
}
});
}
})(); else
{
document.getElementById('list').innerHTML = "<code>ifconfig| grep inet | grep -v inet6 | cut -d\" \" -f2 | tail -n1</code>";
document.getElementById('list').nextSibling.textContent = "In Chrome and Firefox your IP should display automatically, by the power of WebRTCskull.";
}
</script>
<body>
<div id="list"></div>
</body>
and For getting your public ip address you can use
put this code inside your script tag
function getIP(json) {
document.write("My public IP address is: ", json.ip);
}
<script type="application/javascript" src="https://api.ipify.org?format=jsonp&callback=getIP"></script>
Simply
var ip = Request.UserHostAddress;
That's all...
Try:
using System.Net;
public static string GetIpAddress() // Get IP Address
{
string ip = "";
IPHostEntry ipEntry = Dns.GetHostEntry(GetCompCode());
IPAddress[] addr = ipEntry.AddressList;
ip = addr[2].ToString();
return ip;
}
public static string GetCompCode() // Get Computer Name
{
string strHostName = "";
strHostName = Dns.GetHostName();
return strHostName;
}
I'm trying to get the public IP address of the client using asp.net (mvc4) app. when I use
HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"] if gives me an empty string, and when I use HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"] it send a string like this "::1" (without double quotes).
is it related to IIS express ??? how can i get the client IP using asp.net ??
thanks.
Here's the method I use to get the IP address:
private static string GetIPAddress()
{
try
{
if (System.ServiceModel.OperationContext.Current != null)
{
var endpoint = OperationContext.Current.IncomingMessageProperties[RemoteEndpointMessageProperty.Name] as RemoteEndpointMessageProperty;
return endpoint.Address;
}
if (System.Web.HttpContext.Current != null)
{
// Check proxied IP address
if (HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"] != null)
return HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"] + " via " +
HttpContext.Current.Request.UserHostAddress;
else
return HttpContext.Current.Request.UserHostAddress;
}
}
catch { }
return "Unknown";
}
Note that the first section is for WCF services since this code is from my logging code that's shared from both WCF and web projects, so you might just need the second section. You won't get an IP if you're hitting your localhost during development -- you'll get "::1" as you noticed. But you will get it if deployed on a server.
How do you go about getting the IP address of the remote client in a self-hosted SignalR hub? According to this question, you could at one point get it using Context.ServerVariables[], but that seems to be missing from the latest version of SignalR.
Well, in poking around in the recent commits on the SignalR project (specifically this one), I spotted how to do it.
protected string GetIpAddress()
{
var env = Get<IDictionary<string, object>>(Context.Request.Items, "owin.environment");
if (env == null)
{
return null;
}
var ipAddress = Get<string>(env, "server.RemoteIpAddress");
return ipAddress;
}
private static T Get<T>(IDictionary<string, object> env, string key)
{
object value;
return env.TryGetValue(key, out value) ? (T)value : default(T);
}
I didn't try it with the self-hosted SignalR Hub, but with SignalR 2.0, Context.Request doesn't have the Items anymore (at least not what I saw). I figured out, how it works now. (You can reduce the if / else part to a ternary operator, if you like that.)
protected string GetIpAddress()
{
string ipAddress;
object tempObject;
Context.Request.Environment.TryGetValue("server.RemoteIpAddress", out tempObject);
if (tempObject != null)
{
ipAddress = (string)tempObject;
}
else
{
ipAddress = "";
}
return ipAddress;
}
i need to find the IP address of the phone my software is running on. I would have thought that is straight forward but having searched the forums it seems like (unbelievably enough) that there isn't a method for this in windows phone 7 - however, has this changed in windows phone 8? any help would be appreciated.
Yes this is now possible in WP8 without using the multicast solution required for WP7. Note that you will have multiple network interfaces on your phone (e.g. three on my WP8 Emulator)
public static IPAddress Find()
{
List<string> ipAddresses = new List<string>();
var hostnames = NetworkInformation.GetHostNames();
foreach (var hn in hostnames)
{
if (hn.IPInformation != null)
{
string ipAddress = hn.DisplayName;
ipAddresses.Add(ipAddress);
}
}
IPAddress address = IPAddress.Parse(ipAddresses[0]);
return address;
}
HTH
Of course there is a way to find the phones IP address. Here is a MSDN blog blog article which explains how to do it: Finding Your Own IP Address On Windows Phone Mango
I've just tested it on my Nokia Lumia 920 (Windows Phone 8) and it works just fine. However, this just works on WiFi due to the used multicast IP.
Code for Windows RT
public static string GetIpAddress()
{
var address = "";
var icp = NetworkInformation.GetInternetConnectionProfile();
if (icp != null && icp.NetworkAdapter != null)
{
var hostname =
NetworkInformation.GetHostNames()
.SingleOrDefault(
hn =>
hn.IPInformation != null && hn.IPInformation.NetworkAdapter != null
&& hn.IPInformation.NetworkAdapter.NetworkAdapterId
== icp.NetworkAdapter.NetworkAdapterId);
if (hostname != null)
{
address = hostname.CanonicalName;
}
}
return address;
}
I need to get the user's local IP for my ASP.NET application and I'm using this method:
protected string GetIPAddress()
{
System.Web.HttpContext context = System.Web.HttpContext.Current;
string ipAddress = context.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
if (!string.IsNullOrEmpty(ipAddress))
{
string[] addresses = ipAddress.Split(',');
if (addresses.Length != 0)
{
return addresses[0];
}
}
return context.Request.ServerVariables["REMOTE_ADDR"];
}
However, when I publish my website I always get 192.168.2.1 no matter where the user is opening the website from.
Does anyone know how to solve this issue?
Some network devices make use of the X-forwarded-for header. You should check if the requests hitting your application have this header.
You can get the client's IP address from HTTP_X_FORWARDED_FOR or REMOTE_ADDR.
var ipAddress = HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
if (string.IsNullOrEmpty(ipAddress ))
{
ipAddress = HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"];
}
return ipAddress;