made it compilable on non linux systems

Author: shadowy-pycoder

gohpts.go

@@ -13,7 +13,6 @@ import (
 	"math/rand"
 	"net"
 	"net/http"
-	"net/netip"
 	"os"
 	"os/signal"
 	"runtime"
@@ -22,14 +21,11 @@ import (
 	"strings"
 	"sync"
 	"sync/atomic"
-	"syscall"
 	"time"
-	"unsafe"
 
 	"github.com/goccy/go-yaml"
 	"github.com/rs/zerolog"
 	"golang.org/x/net/proxy"
-	"golang.org/x/sys/unix"
 )
 
 const (
@@ -81,7 +77,7 @@ func delHopHeaders(header http.Header) {
 // https://datatracker.ietf.org/doc/html/rfc7230#section-6.1
 func delConnectionHeaders(h http.Header) {
 	for _, f := range h["Connection"] {
-		for _, sf := range strings.Split(f, ",") {
+		for sf := range strings.SplitSeq(f, ",") {
 			if sf = strings.TrimSpace(sf); sf != "" {
 				h.Del(sf)
 			}
@@ -270,7 +266,7 @@ func (p *proxyapp) getSocks() (proxy.Dialer, *http.Client, error) {
 			}
 		}
 		startIdx := int(start % uint32(len(p.availProxyList)))
-		for i := 0; i < chainLength; i++ {
+		for i := range chainLength {
 			idx := (startIdx + i) % len(p.availProxyList)
 			copyProxyList = append(copyProxyList, p.availProxyList[idx])
 		}
@@ -632,188 +628,14 @@ func (p *proxyapp) handler() http.HandlerFunc {
 	}
 }
 
-type tproxyServer struct {
-	listener net.Listener
-	quit     chan struct{}
-	wg       sync.WaitGroup
-	pa       *proxyapp
-}
-
-func newTproxyServer(pa *proxyapp) *tproxyServer {
-	ts := &tproxyServer{
-		quit: make(chan struct{}),
-		pa:   pa,
-	}
-	// https://iximiuz.com/en/posts/go-net-http-setsockopt-example/
-	lc := net.ListenConfig{
-		Control: func(network, address string, conn syscall.RawConn) error {
-			var operr error
-			if err := conn.Control(func(fd uintptr) {
-				operr = unix.SetsockoptInt(int(fd), unix.IPPROTO_TCP, unix.TCP_USER_TIMEOUT, int(timeout*1000))
-				operr = unix.SetsockoptInt(int(fd), unix.SOL_SOCKET, unix.SO_REUSEADDR, 1)
-				if ts.pa.tproxyMode == "tproxy" {
-					operr = unix.SetsockoptInt(int(fd), unix.SOL_IP, unix.IP_TRANSPARENT, 1)
-				}
-			}); err != nil {
-				return err
-			}
-			return operr
-		},
-	}
-
-	ln, err := lc.Listen(context.Background(), "tcp4", ts.pa.tproxyAddr)
-	if err != nil {
-		var msg string
-		if errors.Is(err, unix.EPERM) {
-			msg = "try `sudo setcap 'cap_net_admin+ep` for the binary:"
-		}
-		ts.pa.logger.Fatal().Err(err).Msg(msg)
-	}
-	ts.listener = ln
-	return ts
-}
-
-func (ts *tproxyServer) ListenAndServe() {
-	ts.wg.Add(1)
-	go ts.serve()
-}
-
-func (ts *tproxyServer) serve() {
-	defer ts.wg.Done()
-
-	for {
-		conn, err := ts.listener.Accept()
-		if err != nil {
-			select {
-			case <-ts.quit:
-				return
-			default:
-				ts.pa.logger.Error().Err(err).Msg("")
-			}
-		} else {
-			ts.wg.Add(1)
-			err := conn.SetDeadline(time.Now().Add(timeout))
-			if err != nil {
-				ts.pa.logger.Error().Err(err).Msg("")
-			}
-			go func() {
-				ts.handleConnection(conn)
-				ts.wg.Done()
-			}()
-		}
-	}
-}
-
-func getsockopt(s int, level int, optname int, optval unsafe.Pointer, optlen *uint32) (err error) {
-	_, _, e := unix.Syscall6(unix.SYS_GETSOCKOPT, uintptr(s), uintptr(level), uintptr(optname), uintptr(optval), uintptr(unsafe.Pointer(optlen)), 0)
-	if e != 0 {
-		return e
-	}
-	return nil
-}
-
-func (ts *tproxyServer) getOriginalDst(rawConn syscall.RawConn) (string, error) {
-	var originalDst unix.RawSockaddrInet4
-	err := rawConn.Control(func(fd uintptr) {
-		optlen := uint32(unsafe.Sizeof(originalDst))
-		err := getsockopt(int(fd), unix.SOL_IP, unix.SO_ORIGINAL_DST, unsafe.Pointer(&originalDst), &optlen)
-		if err != nil {
-			ts.pa.logger.Error().Err(err).Msg("[tproxy] getsockopt SO_ORIGINAL_DST failed")
-		}
-	})
-	if err != nil {
-		ts.pa.logger.Error().Err(err).Msg("[tproxy] Failed invoking control connection")
-		return "", err
-	}
-	dstHost := netip.AddrFrom4(originalDst.Addr)
-	dstPort := uint16(originalDst.Port<<8) | originalDst.Port>>8
-	return fmt.Sprintf("%s:%d", dstHost, dstPort), nil
-}
-
-func (ts *tproxyServer) handleConnection(srcConn net.Conn) {
-	var (
-		dstConn net.Conn
-		dst     string
-		err     error
-	)
-	defer srcConn.Close()
-	switch ts.pa.tproxyMode {
-	case "redirect":
-		rawConn, err := srcConn.(*net.TCPConn).SyscallConn()
-		if err != nil {
-			ts.pa.logger.Error().Err(err).Msg("[tproxy] Failed to get raw connection")
-			return
-		}
-		dst, err = ts.getOriginalDst(rawConn)
-		if err != nil {
-			ts.pa.logger.Error().Err(err).Msg("[tproxy] Failed to get destination address")
-			return
-		}
-		ts.pa.logger.Debug().Msgf("[tproxy] getsockopt SO_ORIGINAL_DST %s", dst)
-	case "tproxy":
-		dst = srcConn.LocalAddr().String()
-		ts.pa.logger.Debug().Msgf("[tproxy] IP_TRANSPARENT %s", dst)
-	default:
-		ts.pa.logger.Fatal().Msg("Unknown tproxyMode")
-	}
-	if isLocalAddress(dst) {
-		dstConn, err = net.DialTimeout("tcp", dst, timeout)
-		if err != nil {
-			ts.pa.logger.Error().Err(err).Msgf("[tproxy] Failed connecting to %s", dst)
-			return
-		}
-	} else {
-		sockDialer, _, err := ts.pa.getSocks()
-		if err != nil {
-			ts.pa.logger.Error().Err(err).Msg("[tproxy] Failed getting SOCKS5 client")
-			return
-		}
-		ctx, cancel := context.WithTimeout(context.Background(), timeout)
-		defer cancel()
-		dstConn, err = sockDialer.(proxy.ContextDialer).DialContext(ctx, "tcp", dst)
-		if err != nil {
-			ts.pa.logger.Error().Err(err).Msgf("[tproxy] Failed connecting to %s", dst)
-			return
-		}
-	}
-	defer dstConn.Close()
-
-	dstConnStr := fmt.Sprintf("%s->%s->%s", dstConn.LocalAddr().String(), dstConn.RemoteAddr().String(), dst)
-	srcConnStr := fmt.Sprintf("%s->%s", srcConn.LocalAddr().String(), srcConn.RemoteAddr().String())
-
-	ts.pa.logger.Debug().Msgf("[tproxy] src: %s - dst: %s", srcConnStr, dstConnStr)
-
-	var wg sync.WaitGroup
-	wg.Add(2)
-	go ts.pa.transfer(&wg, dstConn, srcConn, dstConnStr, srcConnStr)
-	go ts.pa.transfer(&wg, srcConn, dstConn, srcConnStr, dstConnStr)
-	wg.Wait()
-}
-
-func (ts *tproxyServer) Shutdown() {
-	close(ts.quit)
-	ts.listener.Close()
-	done := make(chan struct{})
-	go func() {
-		ts.wg.Wait()
-		close(done)
-	}()
-
-	select {
-	case <-done:
-		ts.pa.logger.Info().Msg("[tproxy] Server gracefully shutdown")
-		return
-	case <-time.After(timeout):
-		ts.pa.logger.Error().Msg("[tproxy] Server timed out waiting for connections to finish")
-		return
-	}
-}
-
 func (p *proxyapp) Run() {
 	done := make(chan bool)
 	quit := make(chan os.Signal, 1)
 	signal.Notify(quit, os.Interrupt)
-	tproxyServer := newTproxyServer(p)
+	var tproxyServer *tproxyServer
+	if p.tproxyAddr != "" {
+		tproxyServer = newTproxyServer(p)
+	}
 	if p.proxylist != nil {
 		chainType := p.proxychain.Type
 		go func() {
@@ -827,7 +649,7 @@ func (p *proxyapp) Run() {
 	if p.httpServer != nil {
 		go func() {
 			<-quit
-			if p.tproxyAddr != "" {
+			if tproxyServer != nil {
 				p.logger.Info().Msg("[tproxy] Server is shutting down...")
 				tproxyServer.Shutdown()
 			}
@@ -841,7 +663,7 @@ func (p *proxyapp) Run() {
 			}
 			close(done)
 		}()
-		if p.tproxyAddr != "" {
+		if tproxyServer != nil {
 			go tproxyServer.ListenAndServe()
 		}
 		if p.user != "" && p.pass != "" {