Parse X-Forwarded-For in http request

protocol/http/addr.go

@@ -0,0 +1,22 @@
+package http
+
+import (
+	"net/http"
+	"strings"
+
+	M "github.com/sagernet/sing/common/metadata"
+)
+
+func SourceAddress(request *http.Request) M.Socksaddr {
+	address := M.ParseSocksaddr(request.RemoteAddr)
+	forwardFrom := request.Header.Get("X-Forwarded-For")
+	if forwardFrom != "" {
+		for _, from := range strings.Split(forwardFrom, ",") {
+			originAddr := M.ParseAddr(from)
+			if originAddr.IsValid() {
+				address.Addr = originAddr
+			}
+		}
+	}
+	return address
+}

protocol/http/handshake.go

@@ -48,6 +48,10 @@ func HandleConnection(ctx context.Context, conn net.Conn, reader *std_bufio.Read
 			}
 		}
 
+		if sourceAddress := SourceAddress(request); sourceAddress.IsValid() {
+			metadata.Source = sourceAddress
+		}
+
 		if request.Method == "CONNECT" {
 			portStr := request.URL.Port()
 			if portStr == "" {