Reuse resolved UDP peer for native auth

src/bin/dosh-client.rs

@@ -451,7 +451,8 @@ async fn main() -> Result<()> {
     };
     let cache_requested_env = requested_env(&config, &host, resolved_ssh_config.as_ref());
 
-    let socket = bind_udp_for_peer(resolve_addr(&target_udp_host, dosh_port)?).await?;
+    let target_udp_addr = resolve_addr(&target_udp_host, dosh_port)?;
+    let socket = bind_udp_for_peer(target_udp_addr).await?;
 
     if let Some(mut cached) = credential.clone() {
         cached.udp_host = target_udp_host.clone();
@@ -541,6 +542,7 @@ async fn main() -> Result<()> {
         let native_start = Instant::now();
         match try_native_auth(
             &socket,
+            target_udp_addr,
             &config,
             &requested_server,
             &server,
@@ -1947,23 +1949,28 @@ async fn run_doctor_for_host(
     ) {
         println!("[warn] native endpoint: {warning}");
     }
-    match resolve_addr(&udp_host, dosh_port) {
-        Ok(addr) => println!("[ok] udp resolve: {addr}"),
-        Err(err) => println!("[fail] udp resolve: {err:#}"),
+    let udp_addr = match resolve_addr(&udp_host, dosh_port) {
+        Ok(addr) => {
+            println!("[ok] udp resolve: {addr}");
+            addr
         }
+        Err(err) => {
+            println!("[fail] udp resolve: {err:#}");
+            return Err(err.context("resolve UDP target for native doctor"));
+        }
+    };
     println!(
         "[info] forwarding requested by config: agent={} default_session={}",
         config.forward_agent, config.default_session
     );
-    let socket = bind_udp_for_peer(resolve_addr(&udp_host, dosh_port)?).await?;
+    let socket = bind_udp_for_peer(udp_addr).await?;
     match try_native_auth_check(
         &socket,
+        udp_addr,
         config,
         requested,
         &server,
         ssh_port,
-        &udp_host,
-        dosh_port,
         args.ssh_key.as_deref(),
         Some(&parsed_ssh_config),
     )
@@ -2393,7 +2400,8 @@ async fn run_proxy_stdio_command(config: &dosh::config::ClientConfig, args: &Arg
     let target_udp_host =
         selected_udp_host(requested_udp_host.as_deref(), &server, &resolved_ssh_config)?;
     let dosh_port = args.dosh_port.or(host.port).unwrap_or(config.dosh_port);
-    let socket = bind_udp_for_peer(resolve_addr(&target_udp_host, dosh_port)?).await?;
+    let target_udp_addr = resolve_addr(&target_udp_host, dosh_port)?;
+    let socket = bind_udp_for_peer(target_udp_addr).await?;
     let session = args
         .session
         .clone()
@@ -2407,6 +2415,7 @@ async fn run_proxy_stdio_command(config: &dosh::config::ClientConfig, args: &Arg
     }];
     let (_frame, cred) = try_native_auth(
         &socket,
+        target_udp_addr,
         config,
         &requested_server,
         &server,
@@ -5367,6 +5376,7 @@ async fn send_terminal_udp(socket: &UdpSocket, packet: &[u8], addr: SocketAddr)
 #[allow(clippy::too_many_arguments)]
 async fn try_native_auth(
     socket: &UdpSocket,
+    addr: SocketAddr,
     config: &dosh::config::ClientConfig,
     requested_server: &str,
     server: &str,
@@ -5383,7 +5393,6 @@ async fn try_native_auth(
     requested_env: Vec<EnvVar>,
     allow_passphrase_prompt: bool,
 ) -> Result<(Frame, CachedCredential)> {
-    let addr = resolve_addr(udp_host, udp_port)?;
     let owned_ssh_config;
     let ssh_config = if let Some(ssh_config) = ssh_config_hint {
         ssh_config
@@ -5525,16 +5534,14 @@ async fn try_native_auth(
 #[allow(clippy::too_many_arguments)]
 async fn try_native_auth_check(
     socket: &UdpSocket,
+    addr: SocketAddr,
     config: &dosh::config::ClientConfig,
     requested_server: &str,
     server: &str,
     ssh_port: Option<u16>,
-    udp_host: &str,
-    udp_port: u16,
     cli_identity: Option<&Path>,
     ssh_config_hint: Option<&SshConfig>,
 ) -> Result<NativeAuthCheckOkBody> {
-    let addr = resolve_addr(udp_host, udp_port)?;
     let owned_ssh_config;
     let ssh_config = if let Some(ssh_config) = ssh_config_hint {
         ssh_config