feat: migrate to rust

src/main.rs

@@ -0,0 +1,41 @@
+use std::{env, io};
+use tokio::{
+    io::copy_bidirectional,
+    net::{TcpListener, TcpStream},
+};
+
+#[tokio::main]
+async fn main() -> std::io::Result<()> {
+    let listen_addr = env::var("LISTEN_ADDR").expect("LISTEN_ADDR not set");
+    let target_addr = env::var("UPSTREAM_ADDR").expect("UPSTREAM_ADDR not set");
+
+    println!("Listening on {listen_addr}");
+    println!("Forwarding to {target_addr}");
+
+    let listener = TcpListener::bind(listen_addr).await?;
+
+    loop {
+        match listener.accept().await {
+            Ok((inbound, client_addr)) => {
+                println!("Accepted connection from {client_addr}");
+
+                let target = target_addr.clone();
+                tokio::spawn(async move {
+                    if let Err(e) = handle(inbound, &target).await {
+                        eprintln!("Error handling connection: {e}");
+                    }
+                    println!("Connection from {client_addr} closed");
+                });
+            }
+            Err(e) => {
+                eprintln!("Failed to accept connection: {e}");
+            }
+        }
+    }
+}
+
+async fn handle(mut inbound: TcpStream, target_addr: &str) -> io::Result<()> {
+    let mut outbound = TcpStream::connect(target_addr).await?;
+    copy_bidirectional(&mut inbound, &mut outbound).await?;
+    Ok(())
+}