Merge pull request #346 from fosrl/dev

Fix redirect

flake.nix

@@ -25,7 +25,7 @@
           inherit (pkgs) lib;
 
           # Update version when releasing
-          version = "1.12.4";
+          version = "1.12.5";
         in
         {
           default = self.packages.${system}.pangolin-newt;

netstack2/http_handler.go

@@ -131,18 +131,23 @@ func (l *chanListener) send(conn net.Conn) bool {
 // httpConnCtx – conn wrapper that carries a SubnetRule through the listener
 // ---------------------------------------------------------------------------
 
-// httpConnCtx wraps a net.Conn so the matching SubnetRule can be passed
-// through the chanListener into the http.Server's ConnContext callback,
-// making it available to request handlers via the request context.
+// httpConnCtx wraps a net.Conn so the matching SubnetRule and TLS state can
+// be passed through the chanListener into the http.Server's ConnContext
+// callback, making them available to request handlers via the request context.
 type httpConnCtx struct {
 	net.Conn
-	rule *SubnetRule
+	rule  *SubnetRule
+	isTLS bool // true when the conn was wrapped with tls.Server
 }
 
 // connCtxKey is the unexported context key used to store a *SubnetRule on the
 // per-connection context created by http.Server.ConnContext.
 type connCtxKey struct{}
 
+// connTLSKey is the unexported context key used to store the isTLS flag on
+// the per-connection context created by http.Server.ConnContext.
+type connTLSKey struct{}
+
 // ---------------------------------------------------------------------------
 // Constructor and lifecycle
 // ---------------------------------------------------------------------------
@@ -175,7 +180,8 @@ func (h *HTTPHandler) Start() error {
 		// that handleRequest can retrieve it without any global state.
 		ConnContext: func(ctx context.Context, c net.Conn) context.Context {
 			if cc, ok := c.(*httpConnCtx); ok {
-				return context.WithValue(ctx, connCtxKey{}, cc.rule)
+				ctx = context.WithValue(ctx, connCtxKey{}, cc.rule)
+				ctx = context.WithValue(ctx, connTLSKey{}, cc.isTLS)
 			}
 			return ctx
 		},
@@ -203,19 +209,28 @@ func (h *HTTPHandler) HandleConn(conn net.Conn, rule *SubnetRule) {
 	var effectiveConn net.Conn = conn
 
 	if rule.Protocol == "https" {
-		tlsCfg, err := h.getTLSConfig(rule)
-		if err != nil {
-			logger.Error("HTTP handler: cannot build TLS config for connection from %s: %v",
-				conn.RemoteAddr(), err)
-			conn.Close()
-			return
+		// Only perform TLS termination for connections arriving on port 443.
+		// Connections on port 80 are passed through as plain HTTP so that
+		// handleRequest can issue the HTTP→HTTPS redirect.
+		doTLS := false
+		if tcpAddr, ok := conn.LocalAddr().(*net.TCPAddr); ok {
+			doTLS = tcpAddr.Port == 443
+		}
+		if doTLS {
+			tlsCfg, err := h.getTLSConfig(rule)
+			if err != nil {
+				logger.Error("HTTP handler: cannot build TLS config for connection from %s: %v",
+					conn.RemoteAddr(), err)
+				conn.Close()
+				return
+			}
+			// tls.Server wraps the raw conn; the TLS handshake is deferred until
+			// the first Read, which the http.Server will trigger naturally.
+			effectiveConn = tls.Server(conn, tlsCfg)
 		}
-		// tls.Server wraps the raw conn; the TLS handshake is deferred until
-		// the first Read, which the http.Server will trigger naturally.
-		effectiveConn = tls.Server(conn, tlsCfg)
 	}
 
-	wrapped := &httpConnCtx{Conn: effectiveConn, rule: rule}
+	wrapped := &httpConnCtx{Conn: effectiveConn, rule: rule, isTLS: effectiveConn != conn}
 	if !h.listener.send(wrapped) {
 		// Listener is already closed — clean up the orphaned connection.
 		effectiveConn.Close()
@@ -291,6 +306,9 @@ func (h *HTTPHandler) getProxy(target HTTPTarget) *httputil.ReverseProxy {
 	proxy := &httputil.ReverseProxy{
 		Rewrite: func(pr *httputil.ProxyRequest) {
 			pr.SetURL(targetURL)
+			if host := pr.In.Host; host != "" {
+				pr.Out.Host = host
+			}
 			// SetXForwarded sets X-Forwarded-For from the inbound request's
 			// RemoteAddr (the WireGuard/netstack client address), along with
 			// X-Forwarded-Host and X-Forwarded-Proto. Using Rewrite instead of
@@ -356,9 +374,13 @@ func (h *HTTPHandler) handleRequest(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	// If the rule is HTTPS and a TLS certificate is configured, but the
-	// incoming request arrived over plain HTTP, redirect to HTTPS.
-	if rule.Protocol == "https" && rule.TLSCert != "" && rule.TLSKey != "" && r.TLS == nil {
+	// If the rule is HTTPS but the incoming request arrived over plain HTTP
+	// (port 80), redirect to HTTPS. We use the isTLS flag stored on the
+	// connection context rather than r.TLS, because Go's http.Server calls
+	// ConnectionState() before the TLS handshake completes, so r.TLS.Version
+	// is 0 even for genuine TLS connections at that point.
+	isTLS, _ := r.Context().Value(connTLSKey{}).(bool)
+	if rule.Protocol == "https" && !isTLS {
 		host := r.Host
 		if host == "" {
 			host = r.URL.Host

netstack2/http_handler_tls_test.go

@@ -0,0 +1,48 @@
+package netstack2
+
+import (
+	"crypto/tls"
+	"net"
+	"testing"
+)
+
+// tlsConnStub is a minimal net.Conn that also exposes TLS state, matching
+// *tls.Conn's ConnectionState used by net/http.Server.
+type tlsConnStub struct {
+	net.Conn
+	state tls.ConnectionState
+}
+
+func (t *tlsConnStub) ConnectionState() tls.ConnectionState {
+	return t.state
+}
+
+func TestHTTPConnCtxForwardsConnectionState(t *testing.T) {
+	c1, c2 := net.Pipe()
+	defer c1.Close()
+	defer c2.Close()
+
+	inner := &tlsConnStub{
+		Conn:  c1,
+		state: tls.ConnectionState{Version: tls.VersionTLS12, HandshakeComplete: true},
+	}
+	wrapped := &httpConnCtx{Conn: inner, rule: nil}
+
+	got := wrapped.ConnectionState()
+	if got.Version != tls.VersionTLS12 || !got.HandshakeComplete {
+		t.Fatalf("ConnectionState = %+v, want TLS 1.2 and HandshakeComplete", got)
+	}
+}
+
+func TestHTTPConnCtxConnectionStatePlainTCP(t *testing.T) {
+	c1, c2 := net.Pipe()
+	defer c1.Close()
+	defer c2.Close()
+
+	wrapped := &httpConnCtx{Conn: c1, rule: nil}
+	got := wrapped.ConnectionState()
+	if got.Version != 0 {
+		t.Fatalf("expected zero ConnectionState for plain conn, got %+v", got)
+	}
+	_ = c2
+}