From e77f947d1d6874ea3c95d3a3a759ce5fc7ed43fe Mon Sep 17 00:00:00 2001
From: Toby Chui <tobychui@users.noreply.github.com>
Date: Fri, 10 Oct 2025 14:43:38 +0800
Subject: [PATCH] Added loopback proxy support

- Added support for shortcut loopback setup in local setups
---
 src/mod/dynamicproxy/Server.go              |  1 -
 src/mod/dynamicproxy/dpcore/dpcore.go       | 10 ++++++-
 src/mod/dynamicproxy/proxyRequestHandler.go | 33 +++++++++++++++++----
 src/mod/uptime/uptime.go                    |  1 -
 4 files changed, 36 insertions(+), 9 deletions(-)

diff --git a/src/mod/dynamicproxy/Server.go b/src/mod/dynamicproxy/Server.go
index e0b16bb..a9b1aa7 100644
--- a/src/mod/dynamicproxy/Server.go
+++ b/src/mod/dynamicproxy/Server.go
@@ -92,7 +92,6 @@ func (h *ProxyHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		}
 
 		//Plugin routing
-
 		if h.Parent.Option.PluginManager != nil && h.Parent.Option.PluginManager.HandleRoute(w, r, sep.Tags) {
 			//Request handled by subroute
 			return
diff --git a/src/mod/dynamicproxy/dpcore/dpcore.go b/src/mod/dynamicproxy/dpcore/dpcore.go
index 9b6157e..dcdfbf2 100644
--- a/src/mod/dynamicproxy/dpcore/dpcore.go
+++ b/src/mod/dynamicproxy/dpcore/dpcore.go
@@ -438,7 +438,15 @@ func (p *ReverseProxy) ProxyHTTPS(rw http.ResponseWriter, req *http.Request) (in
 	if !strings.Contains(host, ":") {
 		host += ":443"
 	}
-	serverName := req.URL.Hostname()
+	serverName := ""
+	//if p.Transport != nil {
+	//	if tr, ok := p.Transport.(*http.Transport); ok && tr.TLSClientConfig != nil && tr.TLSClientConfig.ServerName != "" {
+	//		serverName = tr.TLSClientConfig.ServerName
+	//	}
+	//}
+	if serverName == "" {
+		serverName = req.URL.Hostname()
+	}
 
 	// Connect with SNI offload
 	tlsConfig := &tls.Config{
diff --git a/src/mod/dynamicproxy/proxyRequestHandler.go b/src/mod/dynamicproxy/proxyRequestHandler.go
index c1bb15e..757bc55 100644
--- a/src/mod/dynamicproxy/proxyRequestHandler.go
+++ b/src/mod/dynamicproxy/proxyRequestHandler.go
@@ -12,6 +12,7 @@ import (
 	"strings"
 
 	"imuslab.com/zoraxy/mod/dynamicproxy/dpcore"
+	"imuslab.com/zoraxy/mod/dynamicproxy/loadbalance"
 	"imuslab.com/zoraxy/mod/dynamicproxy/rewrite"
 	"imuslab.com/zoraxy/mod/netutils"
 	"imuslab.com/zoraxy/mod/statistic"
@@ -95,27 +96,41 @@ func (router *Router) GetProxyEndpointFromHostname(hostname string) *ProxyEndpoi
 	return targetSubdomainEndpoint
 }
 
-// Clearn URL Path (without the http:// part) replaces // in a URL to /
-func (router *Router) clearnURL(targetUrlOPath string) string {
-	return strings.ReplaceAll(targetUrlOPath, "//", "/")
-}
-
 // Rewrite URL rewrite the prefix part of a virtual directory URL with /
 func (router *Router) rewriteURL(rooturl string, requestURL string) string {
 	rewrittenURL := requestURL
 	rewrittenURL = strings.TrimPrefix(rewrittenURL, strings.TrimSuffix(rooturl, "/"))
 
 	if strings.Contains(rewrittenURL, "//") {
-		rewrittenURL = router.clearnURL(rewrittenURL)
+		rewrittenURL = strings.ReplaceAll(rewrittenURL, "//", "/")
 	}
 	return rewrittenURL
 }
 
+// upstreamHostSwap check if this loopback to one of the proxy rule in the system. If yes, do a shortcut target swap
+// this prevents unnecessary external DNS lookup and connection, return true if swapped and request is already handled
+// by the loopback handler. Only continue if return is false
+func (h *ProxyHandler) upstreamHostSwap(w http.ResponseWriter, r *http.Request, selectedUpstream *loadbalance.Upstream) bool {
+	upstreamHostanme := selectedUpstream.OriginIpOrDomain
+	if strings.Contains(upstreamHostanme, ":") {
+		upstreamHostanme = strings.Split(upstreamHostanme, ":")[0]
+	}
+	loopbackProxyEndpoint := h.Parent.GetProxyEndpointFromHostname(upstreamHostanme)
+	if loopbackProxyEndpoint != nil {
+		//This is a loopback request. Swap the target to the loopback target
+		//h.Parent.Option.Logger.PrintAndLog("proxy", "Detected a loopback request to self. Swap the target to "+loopbackProxyEndpoint.RootOrMatchingDomain, nil)
+		h.hostRequest(w, r, loopbackProxyEndpoint)
+		return true
+	}
+	return false
+}
+
 // Handle host request
 func (h *ProxyHandler) hostRequest(w http.ResponseWriter, r *http.Request, target *ProxyEndpoint) {
 	r.Header.Set("X-Forwarded-Host", r.Host)
 	r.Header.Set("X-Forwarded-Server", "zoraxy-"+h.Parent.Option.HostUUID)
 	reqHostname := r.Host
+
 	/* Load balancing */
 	selectedUpstream, err := h.Parent.loadBalancer.GetRequestUpstreamTarget(w, r, target.ActiveOrigins, target.UseStickySession)
 	if err != nil {
@@ -125,6 +140,12 @@ func (h *ProxyHandler) hostRequest(w http.ResponseWriter, r *http.Request, targe
 		return
 	}
 
+	/* Upstream Host Swap (use to detect loopback to self) */
+	if h.upstreamHostSwap(w, r, selectedUpstream) {
+		//Request handled by the loopback handler
+		return
+	}
+
 	/* WebSocket automatic proxy */
 	requestURL := r.URL.String()
 	if r.Header["Upgrade"] != nil && strings.ToLower(r.Header["Upgrade"][0]) == "websocket" {
diff --git a/src/mod/uptime/uptime.go b/src/mod/uptime/uptime.go
index 7d31da0..1cf897c 100644
--- a/src/mod/uptime/uptime.go
+++ b/src/mod/uptime/uptime.go
@@ -211,7 +211,6 @@ func getWebsiteStatus(url string) (int, error) {
 	}
 
 	resp, err := client.Do(req)
-	//resp, err := client.Get(url)
 	if err != nil {
 		//Try replace the http with https and vise versa
 		rewriteURL := ""