Titanium Web Proxy
A lightweight HTTP(S) proxy server written in C#.
Report bugs or raise issues here. For programming help use StackOverflow with the tag Titanium-Web-Proxy.
Features
- Multithreaded and asynchronous proxy employing server connection pooling, certificate cache, and buffer pooling
- View, modify, redirect and block requests or responses
- Supports mutual SSL authentication, proxy authentication & automatic upstream proxy detection
- Supports kerberos, NTLM authentication over HTTP protocols on windows domain controlled networks
- SOCKS4/5 Proxy support
Installation
Install by nuget
For beta releases on beta branch
Install-Package Titanium.Web.Proxy -Pre
For stable releases on stable branch
Install-Package Titanium.Web.Proxy
Supports
- .NET Standard 2.0 or above
- .NET Framework 4.5 or above
Note to contributors
Road map
- Fix outstanding bugs
- Support reading request and response body as stream #823
- Stop throwing new exceptions #634
- Support HTTP 2.0
Collaborators
The owner of this project, justcoding121, is considered to be inactive from this project due to his busy work schedule. However, we have a collaborator listed below who time and again shows up to maintain this project. Please create pull requests prioritizing bug fixes for the attention of collaborators.
Development environment
Windows
- Visual Studio Code as IDE for .NET
- Visual Studio 2022 as IDE for .NET Framework/.NET
Mac OS
- Visual Studio Code as IDE for .NET
- Visual Studio 2022 as IDE for Mono
Linux
- Visual Studio Code as IDE for .NET
- Mono develop as IDE for Mono
Usage
Refer the HTTP Proxy Server library in your project and look up the test project to learn usage.
Setup HTTP proxy:
var proxyServer = new ProxyServer();
// locally trust root certificate used by this proxy
proxyServer.CertificateManager.TrustRootCertificate(true);
// optionally set the Certificate Engine
// Under Mono only BouncyCastle will be supported
//proxyServer.CertificateManager.CertificateEngine = Network.CertificateEngine.BouncyCastle;
proxyServer.BeforeRequest += OnRequest;
proxyServer.BeforeResponse += OnResponse;
proxyServer.ServerCertificateValidationCallback += OnCertificateValidation;
proxyServer.ClientCertificateSelectionCallback += OnCertificateSelection;
var explicitEndPoint = new ExplicitProxyEndPoint(IPAddress.Any, 8000, true)
{
// Use self-issued generic certificate on all https requests
// Optimizes performance by not creating a certificate for each https-enabled domain
// Useful when certificate trust is not required by proxy clients
//GenericCertificate = new X509Certificate2(Path.Combine(System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location), "genericcert.pfx"), "password")
};
// Fired when a CONNECT request is received
explicitEndPoint.BeforeTunnelConnectRequest += OnBeforeTunnelConnectRequest;
// An explicit endpoint is where the client knows about the existence of a proxy
// So client sends request in a proxy friendly manner
proxyServer.AddEndPoint(explicitEndPoint);
proxyServer.Start();
// Transparent endpoint is useful for reverse proxy (client is not aware of the existence of proxy)
// A transparent endpoint usually requires a network router port forwarding HTTP(S) packets or DNS
// to send data to this endPoint
var transparentEndPoint = new TransparentProxyEndPoint(IPAddress.Any, 8001, true)
{
// Generic Certificate hostname to use
// when SNI is disabled by client
GenericCertificateName = "google.com"
};
proxyServer.AddEndPoint(transparentEndPoint);
//proxyServer.UpStreamHttpProxy = new ExternalProxy() { HostName = "localhost", Port = 8888 };
//proxyServer.UpStreamHttpsProxy = new ExternalProxy() { HostName = "localhost", Port = 8888 };
foreach (var endPoint in proxyServer.ProxyEndPoints)
Console.WriteLine("Listening on '{0}' endpoint at Ip {1} and port: {2} ",
endPoint.GetType().Name, endPoint.IpAddress, endPoint.Port);
// Only explicit proxies can be set as system proxy!
proxyServer.SetAsSystemHttpProxy(explicitEndPoint);
proxyServer.SetAsSystemHttpsProxy(explicitEndPoint);
// wait here (You can use something else as a wait function, I am using this as a demo)
Console.Read();
// Unsubscribe & Quit
explicitEndPoint.BeforeTunnelConnectRequest -= OnBeforeTunnelConnectRequest;
proxyServer.BeforeRequest -= OnRequest;
proxyServer.BeforeResponse -= OnResponse;
proxyServer.ServerCertificateValidationCallback -= OnCertificateValidation;
proxyServer.ClientCertificateSelectionCallback -= OnCertificateSelection;
proxyServer.Stop();
Sample request and response event handlers
private async Task OnBeforeTunnelConnectRequest(object sender, TunnelConnectSessionEventArgs e)
{
string hostname = e.HttpClient.Request.RequestUri.Host;
if (hostname.Contains("dropbox.com"))
{
// Exclude Https addresses you don't want to proxy
// Useful for clients that use certificate pinning
// for example dropbox.com
e.DecryptSsl = false;
}
}
public async Task OnRequest(object sender, SessionEventArgs e)
{
Console.WriteLine(e.HttpClient.Request.Url);
// read request headers
var requestHeaders = e.HttpClient.Request.Headers;
var method = e.HttpClient.Request.Method.ToUpper();
if ((method == "POST" || method == "PUT" || method == "PATCH"))
{
// Get/Set request body bytes
byte[] bodyBytes = await e.GetRequestBody();
e.SetRequestBody(bodyBytes);
// Get/Set request body as string
string bodyString = await e.GetRequestBodyAsString();
e.SetRequestBodyString(bodyString);
// store request
// so that you can find it from response handler
e.UserData = e.HttpClient.Request;
}
// To cancel a request with a custom HTML content
// Filter URL
if (e.HttpClient.Request.RequestUri.AbsoluteUri.Contains("google.com"))
{
e.Ok("<!DOCTYPE html>" +
"<html><body><h1>" +
"Website Blocked" +
"</h1>" +
"<p>Blocked by titanium web proxy.</p>" +
"</body>" +
"</html>");
}
// Redirect example
if (e.HttpClient.Request.RequestUri.AbsoluteUri.Contains("wikipedia.org"))
{
e.Redirect("https://www.paypal.com");
}
}
// Modify response
public async Task OnResponse(object sender, SessionEventArgs e)
{
// read response headers
var responseHeaders = e.HttpClient.Response.Headers;
//if (!e.ProxySession.Request.Host.Equals("medeczane.sgk.gov.tr")) return;
if (e.HttpClient.Request.Method == "GET" || e.HttpClient.Request.Method == "POST")
{
if (e.HttpClient.Response.StatusCode == 200)
{
if (e.HttpClient.Response.ContentType != null && e.HttpClient.Response.ContentType.Trim().ToLower().Contains("text/html"))
{
byte[] bodyBytes = await e.GetResponseBody();
e.SetResponseBody(bodyBytes);
string body = await e.GetResponseBodyAsString();
e.SetResponseBodyString(body);
}
}
}
if (e.UserData != null)
{
// access request from UserData property where we stored it in RequestHandler
var request = (Request)e.UserData;
}
}
// Allows overriding default certificate validation logic
public Task OnCertificateValidation(object sender, CertificateValidationEventArgs e)
{
// set IsValid to true/false based on Certificate Errors
if (e.SslPolicyErrors == System.Net.Security.SslPolicyErrors.None)
e.IsValid = true;
return Task.CompletedTask;
}
// Allows overriding default client certificate selection logic during mutual authentication
public Task OnCertificateSelection(object sender, CertificateSelectionEventArgs e)
{
// set e.clientCertificate to override
return Task.CompletedTask;
}
Console example application screenshot
GUI example application screenshot