A cross-platform asynchronous HTTP(S) proxy server in C#..zip

## Titanium Web Proxy A lightweight HTTP(S) proxy server written in C#. [](https://github.com/justcoding121/titanium-web-proxy/actions/workflows/dotnetcore.yml) [](https://gitter.im/Titanium-Web-Proxy/Lobby?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge) Report bugs or raise issues here. For programming help use [StackOverflow](http://stackoverflow.com/questions/tagged/titanium-web-proxy) with the tag Titanium-Web-Proxy. * [API Documentation](https://justcoding121.github.io/titanium-web-proxy/docs/api/Titanium.Web.Proxy.ProxyServer.html) * [Wiki & Contribution guidelines](https://github.com/justcoding121/Titanium-Web-Proxy/wiki) ### 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](https://www.nuget.org/packages/Titanium.Web.Proxy) For beta releases on [beta branch](https://github.com/justcoding121/Titanium-Web-Proxy/tree/beta) Install-Package Titanium.Web.Proxy -Pre For stable releases on [stable branch](https://github.com/justcoding121/Titanium-Web-Proxy/tree/stable) 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](https://github.com/justcoding121/Titanium-Web-Proxy/issues?q=is%3Aopen+is%3Aissue+label%3Abug) * Support reading request and response body as stream [#823](https://github.com/justcoding121/Titanium-Web-Proxy/issues/823) * Stop throwing new exceptions [#634](https://github.com/justcoding121/Titanium-Web-Proxy/issues/634) * Support HTTP 2.0 #### Collaborators The owner of this project, [justcoding121](https://github.com/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. * [honfika](https://github.com/honfika) ### 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: ```csharp 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 ```csharp 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")