init

2021-11-24 22:40:07 +08:00
commit 954dfba4e0
47 changed files with 3625 additions and 0 deletions
@@ -0,0 +1,180 @@
+package main
+
+import (
+	"bytes"
+	"encoding/binary"
+	"fmt"
+	"math/rand"
+	"net"
+	"sync"
+	"time"
+)
+
+func handshakeC2C(t *P2PTunnel) (err error) {
+	gLog.Printf(LevelDEBUG, "handshakeC2C %s:%d:%d to %s:%d", t.pn.config.Node, t.coneLocalPort, t.coneNatPort, t.config.peerIP, t.config.peerConeNatPort)
+	defer gLog.Printf(LevelDEBUG, "handshakeC2C ok")
+	conn, err := net.ListenUDP("udp", t.la)
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+	_, err = UDPWrite(conn, t.ra, MsgP2P, MsgPunchHandshake, P2PHandshakeReq{ID: t.id})
+	if err != nil {
+		gLog.Println(LevelDEBUG, "handshakeC2C write MsgPunchHandshake error:", err)
+		return err
+	}
+	ra, head, _, _, err := UDPRead(conn, 5000)
+	if err != nil {
+		time.Sleep(time.Millisecond * 200)
+		gLog.Println(LevelDEBUG, err, ", return this error when ip was not reachable, retry read")
+		ra, head, _, _, err = UDPRead(conn, 5000)
+		if err != nil {
+			gLog.Println(LevelDEBUG, "handshakeC2C read MsgPunchHandshake error:", err)
+			return err
+		}
+	}
+	t.ra, _ = net.ResolveUDPAddr("udp", ra.String())
+	// cone server side
+	if head.MainType == MsgP2P && head.SubType == MsgPunchHandshake {
+		gLog.Printf(LevelDEBUG, "read %d handshake ", t.id)
+		UDPWrite(conn, t.ra, MsgP2P, MsgPunchHandshakeAck, P2PHandshakeReq{ID: t.id})
+		_, head, _, _, err = UDPRead(conn, 5000)
+		if err != nil {
+			gLog.Println(LevelDEBUG, "handshakeC2C write MsgPunchHandshakeAck error", err)
+			return err
+		}
+		if head.MainType == MsgP2P && head.SubType == MsgPunchHandshakeAck {
+			gLog.Printf(LevelDEBUG, "read %d handshake ack ", t.id)
+			return nil
+		}
+	}
+	// cone client side will only read handshake ack
+	if head.MainType == MsgP2P && head.SubType == MsgPunchHandshakeAck {
+		gLog.Printf(LevelDEBUG, "read %d handshake ack ", t.id)
+		_, err = UDPWrite(conn, t.ra, MsgP2P, MsgPunchHandshakeAck, P2PHandshakeReq{ID: t.id})
+		if err != nil {
+			gLog.Println(LevelDEBUG, "handshakeC2C write MsgPunchHandshakeAck error", err)
+		}
+		return err
+	}
+	return nil
+}
+
+func handshakeC2S(t *P2PTunnel) error {
+	gLog.Printf(LevelDEBUG, "handshakeC2S start")
+	defer gLog.Printf(LevelDEBUG, "handshakeC2S end")
+	// even if read timeout, continue handshake
+	t.pn.read(t.config.PeerNode, MsgPush, MsgPushHandshakeStart, SymmetricHandshakeAckTimeout)
+	r := rand.New(rand.NewSource(time.Now().UnixNano()))
+	randPorts := r.Perm(65532)
+	conn, err := net.ListenUDP("udp", t.la)
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+	go func() error {
+		gLog.Printf(LevelDEBUG, "send symmetric handshake to %s from %d:%d start", t.config.peerIP, t.coneLocalPort, t.coneNatPort)
+		for i := 0; i < SymmetricHandshakeNum; i++ {
+			// TODO: auto calc cost time
+			time.Sleep(SymmetricHandshakeInterval)
+			dst, err := net.ResolveUDPAddr("udp", fmt.Sprintf("%s:%d", t.config.peerIP, randPorts[i]+2))
+			if err != nil {
+				return err
+			}
+			_, err = UDPWrite(conn, dst, MsgP2P, MsgPunchHandshake, P2PHandshakeReq{ID: t.id})
+			if err != nil {
+				gLog.Println(LevelDEBUG, "handshakeC2S write MsgPunchHandshake error:", err)
+				return err
+			}
+		}
+		gLog.Println(LevelDEBUG, "send symmetric handshake end")
+		return nil
+	}()
+	deadline := time.Now().Add(SymmetricHandshakeAckTimeout)
+	err = conn.SetReadDeadline(deadline)
+	if err != nil {
+		gLog.Println(LevelERROR, "SymmetricHandshakeAckTimeout SetReadDeadline error")
+		return err
+	}
+	// read response of the punching hole ok port
+	result := make([]byte, 1024)
+	_, dst, err := conn.ReadFrom(result)
+	if err != nil {
+		gLog.Println(LevelERROR, "handshakeC2S wait timeout")
+		return err
+	}
+	head := &openP2PHeader{}
+	err = binary.Read(bytes.NewReader(result[:openP2PHeaderSize]), binary.LittleEndian, head)
+	if err != nil {
+		gLog.Println(LevelERROR, "parse p2pheader error:", err)
+		return err
+	}
+	t.ra, _ = net.ResolveUDPAddr("udp", dst.String())
+	if head.MainType == MsgP2P && head.SubType == MsgPunchHandshakeAck {
+		gLog.Printf(LevelDEBUG, "handshakeC2S read %d handshake ack %s", t.id, dst.String())
+		_, err = UDPWrite(conn, dst, MsgP2P, MsgPunchHandshakeAck, P2PHandshakeReq{ID: t.id})
+		return err
+	}
+	return nil
+}
+
+func handshakeS2C(t *P2PTunnel) error {
+	gLog.Printf(LevelDEBUG, "handshakeS2C start")
+	defer gLog.Printf(LevelDEBUG, "handshakeS2C end")
+	gotCh := make(chan *net.UDPAddr, 5)
+	// sequencely udp send handshake, do not parallel send
+	gLog.Printf(LevelDEBUG, "send symmetric handshake to %s:%d start", t.config.peerIP, t.config.peerConeNatPort)
+	gotIt := false
+	gotMtx := sync.Mutex{}
+	for i := 0; i < SymmetricHandshakeNum; i++ {
+		// TODO: auto calc cost time
+		time.Sleep(SymmetricHandshakeInterval)
+		go func(t *P2PTunnel) error {
+			conn, err := net.ListenUDP("udp", nil)
+			if err != nil {
+				gLog.Printf(LevelDEBUG, "listen error")
+				return err
+			}
+			defer conn.Close()
+			UDPWrite(conn, t.ra, MsgP2P, MsgPunchHandshake, P2PHandshakeReq{ID: t.id})
+			_, head, _, _, err := UDPRead(conn, 10000)
+			if err != nil {
+				// gLog.Println(LevelDEBUG, "one of the handshake error:", err)
+				return err
+			}
+			gotMtx.Lock()
+			defer gotMtx.Unlock()
+			if gotIt {
+				return nil
+			}
+			gotIt = true
+			t.la, _ = net.ResolveUDPAddr("udp", conn.LocalAddr().String())
+			if head.MainType == MsgP2P && head.SubType == MsgPunchHandshake {
+				gLog.Printf(LevelDEBUG, "handshakeS2C read %d handshake ", t.id)
+				UDPWrite(conn, t.ra, MsgP2P, MsgPunchHandshakeAck, P2PHandshakeReq{ID: t.id})
+				_, head, _, _, err = UDPRead(conn, 5000)
+				if err != nil {
+					gLog.Println(LevelDEBUG, "handshakeS2C handshake error")
+					return err
+				}
+				if head.MainType == MsgP2P && head.SubType == MsgPunchHandshakeAck {
+					gLog.Printf(LevelDEBUG, "handshakeS2C read %d handshake ack %s", t.id, conn.LocalAddr().String())
+					gotCh <- t.la
+					return nil
+				}
+			}
+			return nil
+		}(t)
+	}
+	gLog.Printf(LevelDEBUG, "send symmetric handshake end")
+	gLog.Println(LevelDEBUG, "handshakeS2C ready, notify peer connect")
+	t.pn.push(t.config.PeerNode, MsgPushHandshakeStart, TunnelMsg{ID: t.id})
+
+	select {
+	case <-time.After(SymmetricHandshakeAckTimeout):
+		return fmt.Errorf("wait handshake failed")
+	case la := <-gotCh:
+		gLog.Println(LevelDEBUG, "symmetric handshake ok", la)
+	}
+	return nil
+}