From fb6b3b0401bac4fa53888e9b4157976df686b606 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E4=B8=96=E7=95=8C?= <i@sekai.icu>
Date: Fri, 23 Sep 2022 18:55:28 +0800
Subject: [PATCH] Fix missing source address from transport connection

---
 adapter/upstream.go | 34 ++++++++++++++++++++++++++++------
 1 file changed, 28 insertions(+), 6 deletions(-)

diff --git a/adapter/upstream.go b/adapter/upstream.go
index 88e51c7a..95dd98ea 100644
--- a/adapter/upstream.go
+++ b/adapter/upstream.go
@@ -38,13 +38,25 @@ type myUpstreamHandlerWrapper struct {
 }
 
 func (w *myUpstreamHandlerWrapper) NewConnection(ctx context.Context, conn net.Conn, metadata M.Metadata) error {
-	w.metadata.Destination = metadata.Destination
-	return w.connectionHandler(ctx, conn, w.metadata)
+	myMetadata := w.metadata
+	if metadata.Source.IsValid() {
+		myMetadata.Source = metadata.Source
+	}
+	if metadata.Destination.IsValid() {
+		myMetadata.Destination = metadata.Destination
+	}
+	return w.connectionHandler(ctx, conn, myMetadata)
 }
 
 func (w *myUpstreamHandlerWrapper) NewPacketConnection(ctx context.Context, conn N.PacketConn, metadata M.Metadata) error {
-	w.metadata.Destination = metadata.Destination
-	return w.packetHandler(ctx, conn, w.metadata)
+	myMetadata := w.metadata
+	if metadata.Source.IsValid() {
+		myMetadata.Source = metadata.Source
+	}
+	if metadata.Destination.IsValid() {
+		myMetadata.Destination = metadata.Destination
+	}
+	return w.packetHandler(ctx, conn, myMetadata)
 }
 
 func (w *myUpstreamHandlerWrapper) NewError(ctx context.Context, err error) {
@@ -78,13 +90,23 @@ func NewUpstreamContextHandler(
 
 func (w *myUpstreamContextHandlerWrapper) NewConnection(ctx context.Context, conn net.Conn, metadata M.Metadata) error {
 	myMetadata := ContextFrom(ctx)
-	myMetadata.Destination = metadata.Destination
+	if metadata.Source.IsValid() {
+		myMetadata.Source = metadata.Source
+	}
+	if metadata.Destination.IsValid() {
+		myMetadata.Destination = metadata.Destination
+	}
 	return w.connectionHandler(ctx, conn, *myMetadata)
 }
 
 func (w *myUpstreamContextHandlerWrapper) NewPacketConnection(ctx context.Context, conn N.PacketConn, metadata M.Metadata) error {
 	myMetadata := ContextFrom(ctx)
-	myMetadata.Destination = metadata.Destination
+	if metadata.Source.IsValid() {
+		myMetadata.Source = metadata.Source
+	}
+	if metadata.Destination.IsValid() {
+		myMetadata.Destination = metadata.Destination
+	}
 	return w.packetHandler(ctx, conn, *myMetadata)
 }