update tun handler

2022-08-21 13:54:52 +08:00
parent d61b1ba1b3
commit ca414f655d
6 changed files with 366 additions and 285 deletions
--- a/handler/tun/client.go
+++ b/handler/tun/client.go
@ -0,0 +1,130 @@
+package tun
+
+import (
+	"context"
+	"io"
+	"net"
+
+	"github.com/go-gost/core/common/bufpool"
+	"github.com/go-gost/core/logger"
+	tun_util "github.com/go-gost/x/internal/util/tun"
+	"github.com/songgao/water/waterutil"
+	"golang.org/x/net/ipv4"
+	"golang.org/x/net/ipv6"
+)
+
+func (h *tunHandler) handleClient(ctx context.Context, conn net.Conn, addr net.Addr, config *tun_util.Config, log logger.Logger) error {
+	cc, err := h.router.Dial(ctx, addr.Network(), addr.String())
+	if err != nil {
+		return err
+	}
+	defer cc.Close()
+
+	return h.transportClient(conn, cc, config, log)
+}
+
+func (h *tunHandler) transportClient(tun net.Conn, conn net.Conn, config *tun_util.Config, log logger.Logger) error {
+	errc := make(chan error, 1)
+
+	go func() {
+		for {
+			err := func() error {
+				b := bufpool.Get(h.md.bufferSize)
+				defer bufpool.Put(b)
+
+				n, err := tun.Read(*b)
+				if err != nil {
+					return err
+				}
+
+				if waterutil.IsIPv4((*b)[:n]) {
+					header, err := ipv4.ParseHeader((*b)[:n])
+					if err != nil {
+						log.Warn(err)
+						return nil
+					}
+
+					log.Tracef("%s >> %s %-4s %d/%-4d %-4x %d",
+						header.Src, header.Dst, ipProtocol(waterutil.IPv4Protocol((*b)[:n])),
+						header.Len, header.TotalLen, header.ID, header.Flags)
+				} else if waterutil.IsIPv6((*b)[:n]) {
+					header, err := ipv6.ParseHeader((*b)[:n])
+					if err != nil {
+						log.Warn(err)
+						return nil
+					}
+
+					log.Tracef("%s >> %s %s %d %d",
+						header.Src, header.Dst,
+						ipProtocol(waterutil.IPProtocol(header.NextHeader)),
+						header.PayloadLen, header.TrafficClass)
+				} else {
+					log.Warn("unknown packet, discarded")
+					return nil
+				}
+
+				_, err = conn.Write((*b)[:n])
+				return err
+			}()
+
+			if err != nil {
+				errc <- err
+				return
+			}
+		}
+	}()
+
+	go func() {
+		for {
+			err := func() error {
+				b := bufpool.Get(h.md.bufferSize)
+				defer bufpool.Put(b)
+
+				n, err := conn.Read(*b)
+				if err != nil {
+					return err
+				}
+
+				if waterutil.IsIPv4((*b)[:n]) {
+					header, err := ipv4.ParseHeader((*b)[:n])
+					if err != nil {
+						log.Warn(err)
+						return nil
+					}
+
+					log.Tracef("%s >> %s %-4s %d/%-4d %-4x %d",
+						header.Src, header.Dst, ipProtocol(waterutil.IPv4Protocol((*b)[:n])),
+						header.Len, header.TotalLen, header.ID, header.Flags)
+				} else if waterutil.IsIPv6((*b)[:n]) {
+					header, err := ipv6.ParseHeader((*b)[:n])
+					if err != nil {
+						log.Warn(err)
+						return nil
+					}
+
+					log.Tracef("%s > %s %s %d %d",
+						header.Src, header.Dst,
+						ipProtocol(waterutil.IPProtocol(header.NextHeader)),
+						header.PayloadLen, header.TrafficClass)
+				} else {
+					log.Warn("unknown packet, discarded")
+					return nil
+				}
+
+				_, err = tun.Write((*b)[:n])
+				return err
+			}()
+
+			if err != nil {
+				errc <- err
+				return
+			}
+		}
+	}()
+
+	err := <-errc
+	if err != nil && err == io.EOF {
+		err = nil
+	}
+	return err
+}