Support for socks5 in pac file.

go.mod

@@ -4,5 +4,6 @@ go 1.13
 
 require (
 	github.com/robertkrimen/otto v0.0.0-20180617131154-15f95af6e78d
+	github.com/txthinking/socks5 v0.0.0-20210716140126-fa1f52a8f2da
 	gopkg.in/sourcemap.v1 v1.0.5 // indirect
 )

go.sum

@@ -1,4 +1,12 @@
+github.com/patrickmn/go-cache v2.1.0+incompatible h1:HRMgzkcYKYpi3C8ajMPV8OFXaaRUnok+kx1WdO15EQc=
+github.com/patrickmn/go-cache v2.1.0+incompatible/go.mod h1:3Qf8kWWT7OJRJbdiICTKqZju1ZixQ/KpMGzzAfe6+WQ=
 github.com/robertkrimen/otto v0.0.0-20180617131154-15f95af6e78d h1:1VUlQbCfkoSGv7qP7Y+ro3ap1P1pPZxgdGVqiTVy5C4=
 github.com/robertkrimen/otto v0.0.0-20180617131154-15f95af6e78d/go.mod h1:xvqspoSXJTIpemEonrMDFq6XzwHYYgToXWj5eRX1OtY=
+github.com/txthinking/runnergroup v0.0.0-20210608031112-152c7c4432bf h1:7PflaKRtU4np/epFxRXlFhlzLXZzKFrH5/I4so5Ove0=
+github.com/txthinking/runnergroup v0.0.0-20210608031112-152c7c4432bf/go.mod h1:CLUSJbazqETbaR+i0YAhXBICV9TrKH93pziccMhmhpM=
+github.com/txthinking/socks5 v0.0.0-20210716140126-fa1f52a8f2da h1:7x8pJcBTdKTBpQbRjZZc9o6CDquXBbvm9UIrR6ZSRJ4=
+github.com/txthinking/socks5 v0.0.0-20210716140126-fa1f52a8f2da/go.mod h1:7NloQcrxaZYKURWph5HLxVDlIwMHJXCPkeWPtpftsIg=
+github.com/txthinking/x v0.0.0-20210326105829-476fab902fbe h1:gMWxZxBFRAXqoGkwkYlPX2zvyyKNWJpxOxCrjqJkm5A=
+github.com/txthinking/x v0.0.0-20210326105829-476fab902fbe/go.mod h1:WgqbSEmUYSjEV3B1qmee/PpP2NYEz4bL9/+mF1ma+s4=
 gopkg.in/sourcemap.v1 v1.0.5 h1:inv58fC9f9J3TK2Y2R1NPntXEn3/wjWHkonhIUODNTI=
 gopkg.in/sourcemap.v1 v1.0.5/go.mod h1:2RlvNNSMglmRrcvhfuzp4hQHwOtjxlbjX7UPY/GXb78=

pac/otto.go

@@ -47,6 +47,7 @@ type OttoEngine struct {
 	loader    Loader
 	isStarted bool
 	vm        *otto.Otto
+	cache     map[string]Proxies
 }
 
 func (o *OttoEngine) Start() error {
@@ -70,6 +71,8 @@ func (o *OttoEngine) Start() error {
 	if o.isStarted {
 		return nil
 	}
+	// Init the cache when start, so the cache will be invalided when reload.
+	o.cache = make(map[string]Proxies)
 	log.Print("initialising OttoEngine")
 	vm := otto.New()
 
@@ -358,6 +361,10 @@ func (o *OttoEngine) FindProxyForURL(in *url.URL) (Proxies, error) {
 	o.mutex.Lock()
 	defer o.mutex.Unlock()
 
+	if cached, ok := o.cache[in.Hostname()]; ok {
+		return cached, nil
+	}
+
 	value, err := o.vm.Call("FindProxyForURL", nil, in.String(), in.Hostname())
 	if err != nil {
 		return Proxies{}, err
@@ -368,5 +375,10 @@ func (o *OttoEngine) FindProxyForURL(in *url.URL) (Proxies, error) {
 		return Proxies{}, err
 	}
 
-	return ParseFindProxyString(findProxyString)
+	r, err := ParseFindProxyString(findProxyString)
+	if err != nil {
+		return Proxies{}, err
+	}
+	o.cache[in.Hostname()] = r
+	return r, nil
 }

pac/pac.go

@@ -54,8 +54,15 @@ type ProxyChecker interface {
 }
 */
 
+const (
+	ProxySchemeHttp   = "http"
+	ProxySchemeHttps  = "https"
+	ProxySchemeSocks5 = "socks5"
+)
+
 // Proxy information struct
 type Proxy struct {
+	Scheme   string
 	Hostname string
 	Port     int
 }
@@ -64,7 +71,7 @@ func (p Proxy) String() string {
 	if p == DirectProxy {
 		return "DIRECT"
 	}
-	return fmt.Sprintf("PROXY %s:%d", p.Hostname, p.Port)
+	return fmt.Sprintf("%s %s:%d", p.Scheme, p.Hostname, p.Port)
 }
 
 // DirectProxy is used to represent a "DIRECT" value

pac/parse.go

@@ -29,8 +29,10 @@ func ParseFindProxyString(s string) (Proxies, error) {
 		portStr  string
 		portInt  int
 		portErr  error
+		scheme   string
 	)
 	for _, statement := range pacStatementSplit.Split(s, 50) {
+		scheme = ""
 		if statement == "" {
 			continue
 		}
@@ -39,10 +41,18 @@ func ParseFindProxyString(s string) (Proxies, error) {
 		case "DIRECT":
 			proxies = append(proxies, DirectProxy)
 		case "PROXY":
+			scheme = ProxySchemeHttp
+		case "SOCKS5":
+			scheme = ProxySchemeSocks5
+		default:
+			return Proxies{}, fmt.Errorf("unsupported PAC command %q", part[0])
+		}
+
+		if scheme != "" {
 			if len(part) != 2 {
 				return Proxies{}, fmt.Errorf("unable to parse proxy details from %q", statement)
 			}
-			url, urlErr = url.Parse("http://" + part[1])
+			url, urlErr = url.Parse(scheme + "://" + part[1])
 			if urlErr != nil {
 				return Proxies{}, urlErr
 			}
@@ -56,11 +66,10 @@ func ParseFindProxyString(s string) (Proxies, error) {
 				return Proxies{}, portErr
 			}
 			proxies = append(proxies, Proxy{
+				Scheme:   scheme,
 				Hostname: url.Hostname(),
 				Port:     portInt,
 			})
-		default:
-			return Proxies{}, fmt.Errorf("unsupported PAC command %q", part[0])
 		}
 	}
 	return proxies, nil

proxyhttphandler.go

@@ -13,6 +13,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/txthinking/socks5"
 	"github.com/williambailey/pacproxy/pac"
 )
 
@@ -86,7 +87,8 @@ func (h *proxyHTTPHandler) lookupProxy(r *http.Request) (*url.URL, error) {
 		return nil, nil
 	}
 	proxyURL := &url.URL{
-		Host: fmt.Sprintf("%s:%d", proxy.Hostname, proxy.Port),
+		Scheme: proxy.Scheme,
+		Host:   fmt.Sprintf("%s:%d", proxy.Hostname, proxy.Port),
 	}
 	if proxyAuth := r.Header.Get("Proxy-Authorization"); proxyAuth != "" {
 		if u, p, ok := parseBasicAuth(proxyAuth); ok {
@@ -118,7 +120,7 @@ func (h *proxyHTTPHandler) doConnectProxy(w http.ResponseWriter, r *http.Request
 			return
 		}
 		defer serverConn.Close()
-	} else {
+	} else if proxyURL.Scheme == pac.ProxySchemeHttp {
 		serverConn, err = h.dialer.Dial("tcp", proxyURL.Hostname()+":"+proxyURL.Port())
 		if err != nil {
 			log.Printf("HTTP Connect Proxy %q: %d %s", r.URL, http.StatusBadGateway, err)
@@ -129,6 +131,14 @@ func (h *proxyHTTPHandler) doConnectProxy(w http.ResponseWriter, r *http.Request
 		removeProxyHeaders(r)
 		//r.WriteProxy(serverConn)
 		r.Write(serverConn) // instead of WriteProxy as this will *hopefully* deal with CONNECT correctly.
+	} else if proxyURL.Scheme == pac.ProxySchemeSocks5 {
+		c, _ := socks5.NewClient(proxyURL.Hostname()+":"+proxyURL.Port(), "", "", 0, 0)
+		serverConn, err = c.Dial("tcp", r.URL.Host)
+		if err != nil {
+			log.Printf("socks5 dial fail:%s", err.Error())
+			http.Error(w, err.Error(), http.StatusBadGateway)
+			return
+		}
 	}
 	hj, ok := w.(http.Hijacker)
 	if !ok {
@@ -144,20 +154,39 @@ func (h *proxyHTTPHandler) doConnectProxy(w http.ResponseWriter, r *http.Request
 		return
 	}
 	defer clientConn.Close()
-	if proxyURL == nil {
+	if proxyURL == nil || proxyURL.Scheme != pac.ProxySchemeHttp {
 		clientConn.Write([]byte("HTTP/1.0 200 OK\r\n\r\n"))
 	}
 	var wg sync.WaitGroup
+	var closeOnce sync.Once
 	wg.Add(1)
 	go func() {
 		defer wg.Done()
-		io.Copy(clientConn, serverConn)
-		clientConn.SetDeadline(time.Now().Add(10 * time.Millisecond))
+		n, err := io.Copy(clientConn, serverConn)
+		if err != nil {
+			log.Printf("%s iocopy from server to client fail:%s", r.URL.Hostname(), err.Error())
+		} else {
+			log.Printf("%s iocopy from server to client done: %d", r.URL.Hostname(), n)
+		}
+		closeOnce.Do(func() {
+			clientConn.Close()
+			serverConn.Close()
+		})
+		clientConn.SetDeadline(time.Now().Add(100 * time.Microsecond))
 	}()
 	wg.Add(1)
 	go func() {
 		defer wg.Done()
-		io.Copy(serverConn, clientConn)
+		n, err := io.Copy(serverConn, clientConn)
+		if err != nil {
+			log.Printf("%s iocopy from client to server fail: %d %s", r.URL.Hostname(), n, err.Error())
+		} else {
+			log.Printf("%s iocopy from client to server done: %d", r.URL.Hostname(), n)
+		}
+		closeOnce.Do(func() {
+			clientConn.Close()
+			serverConn.Close()
+		})
 	}()
 	wg.Wait()
 }