From a2ec08f0333533131f7d071095b8b5e5232f3b70 Mon Sep 17 00:00:00 2001
From: qimaoww <qimaoaa@hotmail.com>
Date: Mon, 9 Mar 2026 02:59:35 +0800
Subject: [PATCH] fix(tunnel): restore upstream ipv6 address normalization
 logic

---
 go-backend/internal/http/handler/control_plane.go | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/go-backend/internal/http/handler/control_plane.go b/go-backend/internal/http/handler/control_plane.go
index f3db8ac..b226c30 100644
--- a/go-backend/internal/http/handler/control_plane.go
+++ b/go-backend/internal/http/handler/control_plane.go
@@ -1620,27 +1620,23 @@ func processServerAddress(serverAddr string) string {
 	if strings.HasPrefix(serverAddr, "[") {
 		return serverAddr
 	}
-	if looksLikeIPv6(serverAddr) {
-		return "[" + strings.Trim(serverAddr, "[]") + "]"
-	}
 
 	idx := strings.LastIndex(serverAddr, ":")
 	if idx < 0 {
+		if looksLikeIPv6(serverAddr) {
+			return "[" + serverAddr + "]"
+		}
 		return serverAddr
 	}
-	if strings.Count(serverAddr, ":") != 1 {
-		return "[" + strings.Trim(serverAddr, "[]") + "]"
-	}
-
 	host := strings.TrimSpace(serverAddr[:idx])
 	port := strings.TrimSpace(serverAddr[idx+1:])
 	if host == "" || port == "" {
 		return serverAddr
 	}
 	if looksLikeIPv6(host) {
-		return "[" + strings.Trim(host, "[]") + "]:" + port
+		return "[" + host + "]:" + port
 	}
-	return host + ":" + port
+	return serverAddr
 }
 
 func normalizeServerAddressInput(serverAddr string) string {