From ac554f670c346d7d5749f389fe70a3375456c5d1 Mon Sep 17 00:00:00 2001
From: ginuerzh <ginuerzh@gmail.com>
Date: Thu, 18 Aug 2022 20:03:03 +0800
Subject: [PATCH] add proxyAgent options for http/http2 handler

---
 README.md         | 2 +-
 README_en.md      | 2 +-
 cmd/gost/route.go | 1 +
 gost.go           | 2 ++
 handler.go        | 8 ++++++++
 http.go           | 9 +++++++--
 http2.go          | 6 +++++-
 selector.go       | 2 +-
 8 files changed, 26 insertions(+), 6 deletions(-)

diff --git a/README.md b/README.md
index 1d111eb5..85f2e83e 100644
--- a/README.md
+++ b/README.md
@@ -58,7 +58,7 @@ go build
 #### Docker
 
 ```bash
-docker pull ginuerzh/gost
+docker run --rm ginuerzh/gost -V
 ```
 
 #### Homebrew
diff --git a/README_en.md b/README_en.md
index 3fe6b9a8..74ffa317 100644
--- a/README_en.md
+++ b/README_en.md
@@ -53,7 +53,7 @@ go build
 #### Docker
 
 ```bash
-docker pull ginuerzh/gost
+docker run --rm ginuerzh/gost -V
 ```
 
 #### Homebrew
diff --git a/cmd/gost/route.go b/cmd/gost/route.go
index a65b0aed..deb71cfc 100644
--- a/cmd/gost/route.go
+++ b/cmd/gost/route.go
@@ -664,6 +664,7 @@ func (r *route) GenRouters() ([]router, error) {
 			gost.IPsHandlerOption(ips),
 			gost.TCPModeHandlerOption(node.GetBool("tcp")),
 			gost.IPRoutesHandlerOption(tunRoutes...),
+			gost.ProxyAgentHandlerOption(node.Get("proxyAgent")),
 		)
 
 		rt := router{
diff --git a/gost.go b/gost.go
index 31d3d568..a17c827b 100644
--- a/gost.go
+++ b/gost.go
@@ -80,6 +80,8 @@ var (
 	// DefaultUserAgent is the default HTTP User-Agent header used by HTTP and websocket.
 	DefaultUserAgent = "Chrome/78.0.3904.106"
 
+	DefaultProxyAgent = "gost/" + Version
+
 	// DefaultMTU is the default mtu for tun/tap device
 	DefaultMTU = 1350
 )
diff --git a/handler.go b/handler.go
index eee515c3..81f505f3 100644
--- a/handler.go
+++ b/handler.go
@@ -42,6 +42,7 @@ type HandlerOptions struct {
 	IPs           []string
 	TCPMode       bool
 	IPRoutes      []IPRoute
+	ProxyAgent    string
 }
 
 // HandlerOption allows a common way to set handler options.
@@ -211,6 +212,13 @@ func IPRoutesHandlerOption(routes ...IPRoute) HandlerOption {
 	}
 }
 
+// ProxyAgentHandlerOption sets the proxy agent for http handler.
+func ProxyAgentHandlerOption(agent string) HandlerOption {
+	return func(opts *HandlerOptions) {
+		opts.ProxyAgent = agent
+	}
+}
+
 type autoHandler struct {
 	options *HandlerOptions
 }
diff --git a/http.go b/http.go
index 1b17e6fd..3275daa6 100644
--- a/http.go
+++ b/http.go
@@ -173,7 +173,12 @@ func (h *httpHandler) handleRequest(conn net.Conn, req *http.Request) {
 		ProtoMinor: 1,
 		Header:     http.Header{},
 	}
-	resp.Header.Add("Proxy-Agent", "gost/"+Version)
+
+	proxyAgent := DefaultProxyAgent
+	if h.options.ProxyAgent != "" {
+		proxyAgent = h.options.ProxyAgent
+	}
+	resp.Header.Add("Proxy-Agent", proxyAgent)
 
 	if !Can("tcp", host, h.options.Whitelist, h.options.Blacklist) {
 		log.Logf("[http] %s - %s : Unauthorized to tcp connect to %s",
@@ -287,7 +292,7 @@ func (h *httpHandler) handleRequest(conn net.Conn, req *http.Request) {
 
 	if req.Method == http.MethodConnect {
 		b := []byte("HTTP/1.1 200 Connection established\r\n" +
-			"Proxy-Agent: gost/" + Version + "\r\n\r\n")
+			"Proxy-Agent: " + proxyAgent + "\r\n\r\n")
 		if Debug {
 			log.Logf("[http] %s <- %s\n%s", conn.RemoteAddr(), conn.LocalAddr(), string(b))
 		}
diff --git a/http2.go b/http2.go
index 1c3cf5a9..72c48906 100644
--- a/http2.go
+++ b/http2.go
@@ -365,7 +365,11 @@ func (h *http2Handler) roundTrip(w http.ResponseWriter, r *http.Request) {
 		log.Logf("[http2] %s - %s\n%s", r.RemoteAddr, laddr, string(dump))
 	}
 
-	w.Header().Set("Proxy-Agent", "gost/"+Version)
+	proxyAgent := DefaultProxyAgent
+	if h.options.ProxyAgent != "" {
+		proxyAgent = h.options.ProxyAgent
+	}
+	w.Header().Set("Proxy-Agent", proxyAgent)
 
 	if !Can("tcp", host, h.options.Whitelist, h.options.Blacklist) {
 		log.Logf("[http2] %s - %s : Unauthorized to tcp connect to %s",
diff --git a/selector.go b/selector.go
index 12545aca..bff6d11f 100644
--- a/selector.go
+++ b/selector.go
@@ -12,7 +12,7 @@ import (
 
 var (
 	// ErrNoneAvailable indicates there is no node available.
-	ErrNoneAvailable = errors.New("none available")
+	ErrNoneAvailable = errors.New("none node available")
 )
 
 // NodeSelector as a mechanism to pick nodes and mark their status.