init

overlaytcp.go

@@ -0,0 +1,85 @@
+package main
+
+import (
+	"bytes"
+	"encoding/binary"
+	"net"
+	"time"
+)
+
+// implement io.Writer
+type overlayTCP struct {
+	tunnel      *P2PTunnel
+	conn        net.Conn
+	id          uint64
+	rtid        uint64
+	running     bool
+	isClient    bool
+	appID       uint64
+	appKey      uint64
+	appKeyBytes []byte
+}
+
+func (otcp *overlayTCP) run() {
+	gLog.Printf(LevelINFO, "%d overlayTCP run start", otcp.id)
+	defer gLog.Printf(LevelINFO, "%d overlayTCP run end", otcp.id)
+	otcp.running = true
+	buffer := make([]byte, ReadBuffLen+PaddingSize)
+	readBuf := buffer[:ReadBuffLen]
+	encryptData := make([]byte, ReadBuffLen+PaddingSize) // 16 bytes for padding
+	tunnelHead := new(bytes.Buffer)
+	relayHead := new(bytes.Buffer)
+	binary.Write(relayHead, binary.LittleEndian, otcp.rtid)
+	binary.Write(tunnelHead, binary.LittleEndian, otcp.id)
+	for otcp.running && otcp.tunnel.isRuning() {
+		otcp.conn.SetReadDeadline(time.Now().Add(time.Second * 5))
+		dataLen, err := otcp.conn.Read(readBuf)
+		if err != nil {
+			if ne, ok := err.(net.Error); ok && ne.Timeout() {
+				continue
+			}
+			// overlay tcp connection normal close, debug log
+			gLog.Printf(LevelDEBUG, "overlayTCP %d read error:%s,close it", otcp.id, err)
+			break
+		} else {
+			payload := readBuf[:dataLen]
+			if otcp.appKey != 0 {
+				payload, _ = encryptBytes(otcp.appKeyBytes, encryptData, buffer[:dataLen], dataLen)
+			}
+			writeBytes := append(tunnelHead.Bytes(), payload...)
+			if otcp.rtid == 0 {
+				otcp.tunnel.conn.WriteBytes(MsgP2P, MsgOverlayData, writeBytes)
+			} else {
+				// write raley data
+				all := append(relayHead.Bytes(), encodeHeader(MsgP2P, MsgOverlayData, uint32(len(writeBytes)))...)
+				all = append(all, writeBytes...)
+				otcp.tunnel.conn.WriteBytes(MsgP2P, MsgRelayData, all)
+				gLog.Printf(LevelDEBUG, "write relay data to %d:%d bodylen=%d", otcp.rtid, otcp.id, len(writeBytes))
+			}
+		}
+	}
+	otcp.conn.Close()
+	otcp.tunnel.overlayConns.Delete(otcp.id)
+	// notify peer disconnect
+	if otcp.isClient {
+		req := OverlayDisconnectReq{ID: otcp.id}
+		if otcp.rtid == 0 {
+			otcp.tunnel.conn.WriteMessage(MsgP2P, MsgOverlayDisconnectReq, &req)
+		} else {
+			// write relay data
+			msg, _ := newMessage(MsgP2P, MsgOverlayDisconnectReq, &req)
+			msgWithHead := append(relayHead.Bytes(), msg...)
+			otcp.tunnel.conn.WriteBytes(MsgP2P, MsgRelayData, msgWithHead)
+		}
+	}
+}
+
+// calling by p2pTunnel
+func (otcp *overlayTCP) Write(buff []byte) (n int, err error) {
+	// add mutex when multi-thread calling
+	n, err = otcp.conn.Write(buff)
+	if err != nil {
+		otcp.tunnel.overlayConns.Delete(otcp.id)
+	}
+	return
+}