#![deny(warnings)] use std::convert::Infallible; use std::net::SocketAddr; use hyper::service::{make_service_fn, service_fn}; use hyper::upgrade::Upgraded; use hyper::{Body, Client, Method, Request, Response, Server}; use tokio::net::TcpStream; type HttpClient = Client; // To try this example: // 1. cargo run --example http_proxy // 2. config http_proxy in command line // $ export http_proxy=http://127.0.0.1:8100 // $ export https_proxy=http://127.0.0.1:8100 // 3. send requests // $ curl -i https://www.some_domain.com/ #[tokio::main] async fn main() { let addr = SocketAddr::from(([127, 0, 0, 1], 8100)); let client = Client::builder() .http1_title_case_headers(true) .http1_preserve_header_case(true) .build_http(); let make_service = make_service_fn(move |_| { let client = client.clone(); async move { Ok::<_, Infallible>(service_fn(move |req| proxy(client.clone(), req))) } }); let server = Server::bind(&addr) .http1_preserve_header_case(true) .http1_title_case_headers(true) .serve(make_service); println!("Listening on http://{}", addr); if let Err(e) = server.await { eprintln!("server error: {}", e); } } async fn proxy(client: HttpClient, req: Request) -> Result, hyper::Error> { println!("req: {:?}", req); if Method::CONNECT == req.method() { // Received an HTTP request like: // ``` // CONNECT www.domain.com:443 HTTP/1.1 // Host: www.domain.com:443 // Proxy-Connection: Keep-Alive // ``` // // When HTTP method is CONNECT we should return an empty body // then we can eventually upgrade the connection and talk a new protocol. // // Note: only after client received an empty body with STATUS_OK can the // connection be upgraded, so we can't return a response inside // `on_upgrade` future. if let Some(addr) = host_addr(req.uri()) { tokio::task::spawn(async move { match hyper::upgrade::on(req).await { Ok(upgraded) => { if let Err(e) = tunnel(upgraded, addr).await { eprintln!("server io error: {}", e); }; } Err(e) => eprintln!("upgrade error: {}", e), } }); Ok(Response::new(Body::empty())) } else { eprintln!("CONNECT host is not socket addr: {:?}", req.uri()); let mut resp = Response::new(Body::from("CONNECT must be to a socket address")); *resp.status_mut() = http::StatusCode::BAD_REQUEST; Ok(resp) } } else { client.request(req).await } } fn host_addr(uri: &http::Uri) -> Option { uri.authority().and_then(|auth| Some(auth.to_string())) } // Create a TCP connection to host:port, build a tunnel between the connection and // the upgraded connection async fn tunnel(mut upgraded: Upgraded, addr: String) -> std::io::Result<()> { // Connect to remote server let mut server = TcpStream::connect(addr).await?; // Proxying data let (from_client, from_server) = tokio::io::copy_bidirectional(&mut upgraded, &mut server).await?; // Print message when done println!( "client wrote {} bytes and received {} bytes", from_client, from_server ); Ok(()) }