add http proxy

add http proxy

add proxy code

add proxy

models/plugin/http-proxy/config/config.json

@@ -0,0 +1,3 @@
+{
+    "port":":8080"
+}

models/plugin/http-proxy/proxy/config.go

@@ -0,0 +1,32 @@
+package proxy
+
+import (
+	"bufio"
+	"encoding/json"
+	"os"
+)
+
+// Config 保存代理服务器的配置
+type Config struct {
+	Port string `json:"port"`
+	Auth bool   `json:"auth"`
+
+	User map[string]string `json:"user"`
+}
+
+// 从指定json文件读取config配置
+func (c *Config) GetConfig(filename string) error {
+
+	configFile, err := os.Open(filename)
+	if err != nil {
+		return err
+	}
+	defer configFile.Close()
+
+	br := bufio.NewReader(configFile)
+	err = json.NewDecoder(br).Decode(c)
+	if err != nil {
+		return err
+	}
+	return nil
+}

models/plugin/http-proxy/proxy/proxy.go

@@ -0,0 +1,201 @@
+package proxy
+
+import (
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"os"
+	"time"
+
+	"github.com/fatedier/frp/models/plugin"
+	"github.com/fatedier/frp/utils/log"
+	wrap "github.com/fatedier/frp/utils/net"
+)
+
+var (
+	HTTP_200  = []byte("HTTP/1.1 200 Connection Established\r\n\r\n")
+	ProxyName = "default-proxy"
+	cnfg      Config
+)
+
+func init() {
+	// 加载配置文件
+	err := cnfg.GetConfig("../config/config.json")
+	if err != nil {
+		log.Error("can not load config file:%v\n", err)
+		os.Exit(-1)
+	}
+	plugin.Register(ProxyName, NewProxyPlugin)
+}
+
+type ProxyServer struct {
+	Tr *http.Transport
+}
+
+type Proxy struct {
+	Server *http.Server
+	Ln     net.Listener
+}
+
+func NewProxyPlugin(params map[string]string) (p plugin.Plugin, err error) {
+
+	listen, err := net.Listen("tcp", cnfg.Port)
+	if err != nil {
+		log.Error("can not listen %v port", cnfg.Port)
+		return
+	}
+
+	p = &Proxy{
+		Server: NewProxyServer(),
+		Ln:     listen,
+	}
+	return
+}
+
+func (proxy *Proxy) Name() string {
+	return ProxyName
+}
+
+// right??
+func (proxy *Proxy) Handle(conn io.ReadWriteCloser) {
+	wrapConn := wrap.WrapReadWriteCloserToConn(conn)
+
+	remote, err := net.Dial("tcp", cnfg.Port)
+	if err != nil {
+		log.Error("dial tcp error:%v", err)
+		return
+	}
+
+	// or tcp.Join(remote,wrapConn)
+	_, err = io.Copy(remote, wrapConn)
+	if err != nil && err != io.EOF {
+		log.Error("io copy data error:%v", err)
+		return
+	}
+	return
+}
+
+func (proxy *Proxy) Close() error {
+	return proxy.Server.Close()
+}
+
+func NewProxyServer() *http.Server {
+
+	return &http.Server{
+		Addr:           cnfg.Port,
+		Handler:        &ProxyServer{Tr: http.DefaultTransport.(*http.Transport)},
+		ReadTimeout:    10 * time.Second,
+		WriteTimeout:   10 * time.Second,
+		MaxHeaderBytes: 1 << 20,
+	}
+}
+
+func (proxy *ProxyServer) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
+	defer func() {
+		if err := recover(); err != nil {
+			rw.WriteHeader(http.StatusInternalServerError)
+			log.Error("Panic: %v", err)
+			fmt.Fprintf(rw, fmt.Sprintln(err))
+		}
+	}()
+
+	if req.Method == "CONNECT" { // 是connect连接
+		proxy.HttpsHandler(rw, req)
+	} else {
+		proxy.HttpHandler(rw, req)
+	}
+}
+
+// 处理普通的http请求
+func (proxy *ProxyServer) HttpHandler(rw http.ResponseWriter, req *http.Request) {
+	log.Info("is sending request %v %v ", req.Method, req.URL.Host)
+	removeProxyHeaders(req) // 去除不必要的头
+
+	resp, err := proxy.Tr.RoundTrip(req)
+	if err != nil {
+		log.Error("transport RoundTrip error: %v", err)
+		http.Error(rw, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	defer resp.Body.Close()
+
+	clearHeaders(rw.Header()) // 得到一个空的Header
+	copyHeaders(rw.Header(), resp.Header)
+	rw.WriteHeader(resp.StatusCode)
+
+	nr, err := io.Copy(rw, resp.Body)
+	if err != nil && err != io.EOF {
+		log.Error("got an error when copy remote response to client.%v", err)
+		return
+	}
+	log.Info("copied %v bytes from remote host %v.", nr, req.URL.Host)
+}
+
+// 处理https连接，主要用于CONNECT方法
+func (proxy *ProxyServer) HttpsHandler(rw http.ResponseWriter, req *http.Request) {
+	log.Info("[CONNECT] tried to connect to remote host %v", req.URL.Host)
+
+	hj, _ := rw.(http.Hijacker)
+	client, _, err := hj.Hijack() //获取客户端与代理服务器的tcp连接
+	if err != nil {
+		log.Error("failed to get Tcp connection of", req.RequestURI)
+		http.Error(rw, "Failed", http.StatusBadRequest)
+		return
+	}
+
+	remote, err := net.Dial("tcp", req.URL.Host) //建立服务端和代理服务器的tcp连接
+	if err != nil {
+		log.Error("failed to connect %v", req.RequestURI)
+		http.Error(rw, "Failed", http.StatusBadRequest)
+		client.Close()
+		return
+	}
+
+	client.Write(HTTP_200)
+
+	go copyRemoteToClient(remote, client)
+	go copyRemoteToClient(client, remote)
+}
+
+// data copy between two socket
+func copyRemoteToClient(remote, client net.Conn) {
+	defer func() {
+		remote.Close()
+		client.Close()
+	}()
+
+	nr, err := io.Copy(remote, client)
+	if err != nil && err != io.EOF {
+		log.Error("got an error when handles CONNECT %v", err)
+		return
+	}
+	log.Info("[CONNECT]  transported %v bytes betwwen %v and %v", nr, remote.RemoteAddr(), client.RemoteAddr())
+}
+
+func copyHeaders(dst, src http.Header) {
+	for key, values := range src {
+		for _, value := range values {
+			dst.Add(key, value)
+		}
+	}
+}
+
+func clearHeaders(headers http.Header) {
+	for key, _ := range headers {
+		headers.Del(key)
+	}
+}
+
+func removeProxyHeaders(req *http.Request) {
+	req.RequestURI = ""
+	req.Header.Del("Proxy-Connection")
+	req.Header.Del("Connection")
+	req.Header.Del("Keep-Alive")
+	req.Header.Del("Proxy-Authenticate")
+	req.Header.Del("Proxy-Authorization")
+	req.Header.Del("TE")
+	req.Header.Del("Trailers")
+	req.Header.Del("Transfer-Encoding")
+	req.Header.Del("Upgrade")
+}