func echoServer(Address *string, Message *string) {
	var c net.PacketConn
	var err error

	c, err = net.ListenPacket("sctp", *settings.Address)

	if err != nil {
		log.Printf("Error listening: %v", err)
		os.Exit(-1)
	}
	defer c.Close()

	for {
		msg := make([]byte, 2048)
		log.Printf("Listening on %s", *settings.Address)
		_, addr, err := c.ReadFrom(msg)
		if err != nil {
			log.Printf("Error: %v ", err)
			break
		}
		fmt.Println("Message: " + string(msg))
		c.WriteTo(msg, addr)
	}

}
Example #2
0
func serveTestUdp(in net.PacketConn, pdu_txt string, waiter *sync.WaitGroup) {

	defer func() {
		waiter.Done()
	}()

	var byteArray [10000]byte

	for {
		_, addr, err := in.ReadFrom(byteArray[:])
		if nil != err {
			fmt.Println("[test] read failed", err.Error())
			break
		}

		fmt.Println("[test] recv ok, send at next step")

		bin, err := hex.DecodeString(pdu_txt)
		if nil != err {
			fmt.Println("[test]", err.Error())
		} else {
			if _, err = in.WriteTo(bin, addr); nil != err {
				fmt.Println("[test] write failed", err.Error())
				break
			}
		}
	}
}
func sendPacket(conn net.PacketConn, destination *net.IPAddr, payload []byte, seq int) {
	packet := make([]byte, len(payload)+8)
	packet[0] = 8
	packet[1] = 0
	packet[4] = uint8(os.Getpid() >> 8)
	packet[5] = uint8(os.Getpid() & 0xff)
	packet[6] = uint8(seq >> 8)
	packet[7] = uint8(seq & 0xff)
	copy(packet[8:], payload)

	cklen := len(packet)
	cksum := uint32(0)
	for i := 0; i < cklen-1; i += 2 {
		cksum += uint32(packet[i+1])<<8 | uint32(packet[i])
	}
	if cklen&1 == 1 {
		cksum += uint32(packet[cklen-1])
	}
	cksum = (cksum >> 16) + (cksum & 0xffff)
	cksum = cksum + (cksum >> 16)

	packet[2] ^= uint8(^cksum & 0xff)
	packet[3] ^= uint8(^cksum >> 8)

	_, err := conn.WriteTo(packet, destination)
	if err != nil {
		panic(err)
	}
}
Example #4
0
func WriteFile(w io.Writer, conn net.PacketConn, remoteAddress net.Addr, packet []byte, tid uint16) (int, net.Addr, error) {
	// Read data packet
	n, replyAddr, err := conn.ReadFrom(packet)
	if err != nil {
		return n, replyAddr, fmt.Errorf("Error reading packet: %v", err)
	}

	opcode, err := GetOpCode(packet)
	if err != nil {
		return n, replyAddr, fmt.Errorf("Error getting opcode: %v", err)
	}
	if opcode != OpDATA {
		return n, replyAddr, fmt.Errorf("Expected DATA packet, got %v\n", opcode)
	}

	packetTID := binary.BigEndian.Uint16(packet[2:4])
	if packetTID != tid {
		SendError(5, "Unknown transfer id", conn, remoteAddress)
		return n, replyAddr, fmt.Errorf("Expected TID %d, got %d\n", tid, packetTID)
	}

	// Write data to disk
	_, err = w.Write(packet[4:n])
	if err != nil {
		return n, replyAddr, fmt.Errorf("Error writing: %v", err)
	}

	ack := CreateAckPacket(tid)
	_, err = conn.WriteTo(ack, replyAddr)
	if err != nil {
		return n, replyAddr, fmt.Errorf("Error writing ACK packet: %v", err)
	}

	return n, replyAddr, nil
}
Example #5
0
// sends an ABORT packet to the specified peer
func sendAbort(c net.PacketConn, addr net.Addr, tag []byte) {
	p := NewPacket(4)
	p.D[0] = byte(PacketAbort)
	copy(p.D[1:4], tag)
	c.WriteTo(p.D, addr)
	p.Free()
}
Example #6
0
// RFC 3489: Clients SHOULD retransmit the request starting with an interval
// of 100ms, doubling every retransmit until the interval reaches 1.6s.
// Retransmissions continue with intervals of 1.6s until a response is
// received, or a total of 9 requests have been sent.
func (v *packet) send(conn net.PacketConn, addr net.Addr) (*packet, error) {
	timeout := 100
	for i := 0; i < 9; i++ {
		length, err := conn.WriteTo(v.bytes(), addr)
		if err != nil {
			return nil, err
		}
		if length != len(v.bytes()) {
			return nil, errors.New("Error in sending data.")
		}
		conn.SetReadDeadline(time.Now().Add(time.Duration(timeout) * time.Millisecond))
		if timeout < 1600 {
			timeout *= 2
		}
		packetBytes := make([]byte, 1024)
		length, _, err = conn.ReadFrom(packetBytes)
		if err == nil {
			return newPacketFromBytes(packetBytes[0:length])
		} else {
			if !err.(net.Error).Timeout() {
				return nil, err
			}
		}
	}
	return nil, nil
}
Example #7
0
func SendError(code uint16, message string, conn net.PacketConn, remoteAddress net.Addr) error {
	errPacket := CreateErrorPacket(0, message)
	_, err := conn.WriteTo(errPacket, remoteAddress)
	if err != nil {
		return fmt.Errorf("Error writing error packet: %v", err)
	}
	return nil
}
Example #8
0
func benchmarkReadWriteNetUDP(b *testing.B, c net.PacketConn, wb, rb []byte, dst net.Addr) {
	if _, err := c.WriteTo(wb, dst); err != nil {
		b.Fatal(err)
	}
	if _, _, err := c.ReadFrom(rb); err != nil {
		b.Fatal(err)
	}
}
Example #9
0
func MGCPCommandRespondEcho(msg MGCPCommand, conn net.PacketConn, addr net.Addr) {
	str_reply := fmt.Sprintf("%s", msg)

	if _, err := conn.WriteTo([]byte(str_reply), addr); err != nil {
		fmt.Println(err)
	}

}
Example #10
0
func (p *Packet) Send(c net.PacketConn, addr net.Addr) error {
	buf, err := p.Encode()
	if err != nil {
		return err
	}

	_, err = c.WriteTo(buf, addr)
	return err
}
Example #11
0
func benchmarkReadWriteNetUDP(b *testing.B, c net.PacketConn, dst net.Addr) {
	if _, err := c.WriteTo([]byte("HELLO-R-U-THERE"), dst); err != nil {
		b.Fatalf("net.PacketConn.WriteTo failed: %v", err)
	}
	rb := make([]byte, 128)
	if _, _, err := c.ReadFrom(rb); err != nil {
		b.Fatalf("net.PacketConn.ReadFrom failed: %v", err)
	}
}
Example #12
0
func (p *Packet) Send(c net.PacketConn, addr net.Addr) error {
	var buf [4096]byte
	n, _, err := p.Encode(buf[:])
	if err != nil {
		return err
	}

	n, err = c.WriteTo(buf[:n], addr)
	return err
}
Example #13
0
func packetEcho(c net.PacketConn) {
	defer c.Close()
	buf := make([]byte, 65536)
	for {
		n, addr, err := c.ReadFrom(buf)
		if err != nil {
			return
		}
		if _, err := c.WriteTo(buf[:n], addr); err != nil {
			return
		}
	}
}
Example #14
0
func MGCPCommandRespondErr(msg MGCPCommand, conn net.PacketConn, addr net.Addr) {
	var reply MGCPResponse
	reply.ResponseCode = "504"
	reply.TransID = msg.TransID
	reply.ResponseStr = "ERR"

	str_reply := fmt.Sprintf("%s", reply)

	if _, err := conn.WriteTo([]byte(str_reply), addr); err != nil {
		fmt.Println(err)
	}

}
func handleClient(conn net.PacketConn) {
	var buf [512]byte

	_, addr, err := conn.ReadFrom(buf[0:])

	if err != nil {
		return
	}

	daytime := time.Now()

	msg := fmt.Sprint(daytime)

	conn.WriteTo([]byte(msg), addr)
}
Example #16
0
// ReadFileLoop will read from r in blockSize chunks, sending each chunk to through conn
// to remoteAddr. After each send it will wait for an ACK packet. It will loop until
// EOF on r.
func ReadFileLoop(r io.Reader, conn net.PacketConn, remoteAddr net.Addr, blockSize int) (int, error) {
	var tid uint16
	var bytesRead int

	buffer := make([]byte, blockSize)
	ackBuf := make([]byte, 4)
	for {
		tid++

		n, err := r.Read(buffer)
		if err == io.EOF {
			// We're done
			break
		}
		if err != nil {
			return bytesRead, fmt.Errorf("Error reading data: %v", err)
		}
		bytesRead += n

		packet := createDataPacket(tid, buffer[:n])
		n, err = conn.WriteTo(packet, remoteAddr)
		if err != nil {
			return bytesRead, fmt.Errorf("Error writing data packet: %v", err)
		}

		// Read ack
		i, _, err := conn.ReadFrom(ackBuf)
		if err != nil {
			return bytesRead, fmt.Errorf("Error reading ACK packet: %v", err)
		}
		if i != 4 {
			return bytesRead, fmt.Errorf("Expected 4 bytes read for ACK packet, got %d", i)
		}
		ackTid, err := ParseAckPacket(ackBuf)
		if err != nil {
			return bytesRead, fmt.Errorf("Error parsing ACK packet: %v", err)
		}
		if ackTid != tid {
			return bytesRead, fmt.Errorf("ACK tid: %d, does not match expected: %d", ackTid, tid)
		}
	}
	return bytesRead, nil
}
Example #17
0
// Serve accepts incoming TFTP read requests on the listener l,
// creating a new service goroutine for each. The service goroutines
// use handler to get a byte stream and send it to the client.
func Serve(l net.PacketConn, handler Handler) {
	Log("Listening on %s", l.LocalAddr())
	buf := make([]byte, 512)
	for {
		n, addr, err := l.ReadFrom(buf)
		if err != nil {
			Log("Reading from socket: %s", err)
			continue
		}

		req, err := parseRRQ(addr, buf[:n])
		if err != nil {
			Debug("parseRRQ: %s", err)
			l.WriteTo(mkError(err), addr)
			continue
		}

		go transfer(addr, req, handler)
	}
}
Example #18
0
// Send stdin packets to addr via conn until EOF, then signal master with
// readShutdown.
// If we experience a short write, we just warn about it and discard the
// unwritten data; this is basically required by packet-based connection
// types, since two packets != one big packet.
func packetSend(conn net.PacketConn, addr net.Addr, master chan shutdowns) {
	buf := make([]byte, bufsize)
	for {
		nr, err := os.Stdin.Read(buf[0:])
		if err != nil {
			// We do not attempt to write partial data on a
			// stdin read error.
			if err != io.EOF {
				warnln("stdin read error:", err)
			}
			break
		}
		nw, err := conn.WriteTo(buf[0:nr], addr)
		if err != nil {
			warnln("network write error to", addr, ":", err)
			break
		}
		if nr != nw {
			warnf("short write to %s: %d written of %d\n",
				addr, nw, nr)
		}
	}
	master <- readShutdown
}
Example #19
0
func Main(clusterName, self, buri, secret string, cl *doozer.Conn, udpConn net.PacketConn, listener, webListener net.Listener, pulseInterval, fillDelay, kickTimeout int64) {
	listenAddr := listener.Addr().String()

	canWrite := make(chan bool, 1)
	in := make(chan consensus.Packet, 50)
	out := make(chan consensus.Packet, 50)

	st := store.New()
	pr := &proposer{
		seqns: make(chan int64, alpha),
		props: make(chan *consensus.Prop),
		st:    st,
	}

	calSrv := func(start int64) {
		go gc.Pulse(self, st.Seqns, pr, pulseInterval)
		go gc.Clean(st, 360000, time.Tick(1e9))
		consensus.NewManager(self, start, alpha, in, out, st.Ops, pr.seqns, pr.props, fillDelay, st)
	}

	if cl == nil { // we are the only node in a new cluster
		set(st, "/ctl/name", clusterName, store.Missing)
		set(st, "/ctl/node/"+self+"/addr", listenAddr, store.Missing)
		set(st, "/ctl/node/"+self+"/hostname", os.Getenv("HOSTNAME"), store.Missing)
		set(st, "/ctl/node/"+self+"/version", Version, store.Missing)
		set(st, "/ctl/cal/0", self, store.Missing)
		calSrv(<-st.Seqns)
		// Skip ahead alpha steps so that the registrar can provide a
		// meaningful cluster.
		for i := 0; i < alpha; i++ {
			st.Ops <- store.Op{1 + <-st.Seqns, store.Nop}
		}
		canWrite <- true
	} else {
		setC(cl, "/ctl/node/"+self+"/addr", listenAddr, store.Clobber)
		setC(cl, "/ctl/node/"+self+"/hostname", os.Getenv("HOSTNAME"), store.Clobber)
		setC(cl, "/ctl/node/"+self+"/version", Version, store.Clobber)

		rev, err := cl.Rev()
		if err != nil {
			panic(err)
		}

		stop := make(chan bool, 1)
		go follow(st, cl, rev+1, stop)

		info, err := cl.Walk("/**", rev, 0, -1)
		if err != nil {
			panic(err)
		}
		for _, ev := range info {
			// store.Clobber is okay here because the event
			// has already passed through another store
			mut := store.MustEncodeSet(ev.Path, string(ev.Body), store.Clobber)
			st.Ops <- store.Op{ev.Rev, mut}
		}
		st.Flush()

		ch, err := st.Wait(store.Any, rev+1)
		if err == nil {
			<-ch
		}

		go func() {
			n := activate(st, self, cl)
			calSrv(n)
			advanceUntil(cl, st.Seqns, n+alpha)
			stop <- true
			canWrite <- true
			if buri != "" {
				b, err := doozer.DialUri(buri)
				if err != nil {
					panic(err)
				}
				setC(
					b,
					"/ctl/ns/"+clusterName+"/"+self,
					listenAddr,
					store.Missing,
				)
			}
		}()
	}

	shun := make(chan string, 3) // sufficient for a cluster of 7
	go member.Clean(shun, st, pr)
	go server.ListenAndServe(listener, canWrite, st, pr, secret)

	if secret == "" && webListener != nil {
		web.Store = st
		web.ClusterName = clusterName
		go web.Serve(webListener)
	}

	go func() {
		for p := range out {
			addr, err := net.ResolveUDPAddr(p.Addr)
			if err != nil {
				log.Println(err)
				continue
			}
			n, err := udpConn.WriteTo(p.Data, addr)
			if err != nil {
				log.Println(err)
				continue
			}
			if n != len(p.Data) {
				log.Println("packet len too long:", len(p.Data))
				continue
			}
		}
	}()

	lv := liveness{
		timeout: kickTimeout,
		ival:    kickTimeout / 2,
		times:   make(map[string]int64),
		self:    self,
		shun:    shun,
	}
	for {
		t := time.Nanoseconds()

		buf := make([]byte, maxUDPLen)
		n, addr, err := udpConn.ReadFrom(buf)
		if err == os.EINVAL {
			return
		}
		if err != nil {
			log.Println(err)
			continue
		}

		buf = buf[:n]

		// Update liveness time stamp for this addr
		lv.times[addr.String()] = t
		lv.check(t)

		in <- consensus.Packet{addr.String(), buf}
	}
}
Example #20
0
// process the connection state SHUTDOWN-ACK-SENT
func (c *connection) state_shutdownAckSent(pc net.PacketConn, tq *timerQueue, abortTimer *timer, cd *connectionData) connectionState {

	// Read now returns io.EOF
	c.L.Lock()
	if c.ReadErr == nil {
		c.ReadErr = io.EOF
	}
	unblockRead := c.readData.p != nil
	c.readData.p = nil
	c.L.Unlock()

	if unblockRead {
		c.readData.Done()
	}

	// no longer ACK data
	cd.DisableAcks = true

	// disable T2-rtx
	tq.StopTimer(&cd.RetransmitTimer)

	var (
		incoming        []Packet
		first           = true
		retransmitsLeft = 5

		retransmit = timer{
			Cond: &c.Cond,
		}
	)

	for {
		// retransmit SHUTDOWN-ACK packet
		if first || retransmit.Signaled() {
			first = false
			// process resends of the SHUTDOWN packet
			retransmitsLeft--
			if retransmitsLeft <= 0 {
				return connectionAbort
			}

			// build SHUTDOWN packet
			p := NewPacket(4)
			p.D[0] = byte(PacketShutdownAck)
			copy(p.D[1:4], cd.ConnectionTag[:])

			// Send to peer
			_, err := pc.WriteTo(p.D, c.addr)
			if err != nil {
				c.L.Lock()
				c.ReadErr = err
				c.WriteErr = err
				c.L.Unlock()
				return connectionAbort
			}

			// Start T2-rtx to resend SHUTDOWN-ACK
			tq.StopTimer(&retransmit)
			tq.StartTimer(&retransmit, 400*time.Millisecond)
		}

		// wait for connection to become ready
		c.L.Lock()
		for len(c.Incoming) == 0 && !retransmit.Signaled() && !abortTimer.Signaled() {
			c.Wait()
		}
		incoming = append(incoming, c.Incoming...)
		c.Incoming = c.Incoming[:0]
		c.L.Unlock()

		// has the abort timer been signaled
		if abortTimer.Signaled() {
			return connectionAbort
		}

		// have we found a SHUTDOWN-COMPLETE packet?
		shutdownComplete := false
		for _, p := range incoming {
			if PacketType(p.D[0]) == PacketShutdownComplete {
				shutdownComplete = true
			}
			p.Free()
		}

		// on SHUTDOWN-COMPLETE, transition to CLOSED
		if shutdownComplete {
			return connectionClosed
		}
	}
}
Example #21
0
// process the connection state SHUTDOWN-SENT
func (c *connection) state_shutdownSent(pc net.PacketConn, tq *timerQueue, abortTimer *timer, cd *connectionData) connectionState {

	// no longer ACK data
	cd.DisableAcks = true

	// disable T2-rtx
	tq.StopTimer(&cd.RetransmitTimer)
	retransmit := timer{
		Cond: &c.Cond,
	}

	var (
		currentAck = cd.AcknowlegedBytes() - 1
		incoming   []Packet
	)

	retransmitsLeft := 5
	for {
		// if we have a new outgoing sequence, (re)send SHUTDOWN packet
		if seq := cd.AcknowlegedBytes(); seq != currentAck || retransmit.Signaled() {
			// process resends of the SHUTDOWN packet
			if seq == currentAck {
				retransmitsLeft--
				if retransmitsLeft <= 0 {
					return connectionAbort
				}
			}

			// build SHUTDOWN packet
			currentAck = cd.AcknowlegedBytes()
			p := NewPacket(8)
			p.D[0] = byte(PacketShutdown)
			copy(p.D[1:4], cd.ConnectionTag[:])
			binary.LittleEndian.PutUint32(p.D[4:8], currentAck)

			// Send to peer
			_, err := pc.WriteTo(p.D, c.addr)
			if err != nil {
				c.L.Lock()
				c.ReadErr = err
				c.WriteErr = err
				c.L.Unlock()
				return connectionAbort
			}

			// Start T2-rtx to resend SHUTDOWN
			tq.StopTimer(&retransmit)
			tq.StartTimer(&retransmit, 400*time.Millisecond)
		}

		// wait for connection to become ready
		timerAborted, receivedShutdown := false, false
		c.L.Lock()
		for c.shouldWaitOnCV(tq, cd) && !retransmit.Signaled() {
			timerAborted = abortTimer.Signaled()
			receivedShutdown = cd.ReceivedShutdown
			if timerAborted || receivedShutdown {
				break
			}

			c.Wait()
		}
		incoming = append(incoming, c.Incoming...)
		c.Incoming = c.Incoming[:0]
		c.L.Unlock()

		// on SHUTDOWN, transition to SHUTDOWN-ACK-SENT
		if cd.ReceivedShutdown {
			return connectionShutdownAckSent
		}

		// on SHUTDOWN-ACK, transition to CLOSED
		if cd.ReceivedShutdownAck {
			// Read now returns io.EOF
			c.L.Lock()
			if c.ReadErr == nil {
				c.ReadErr = io.EOF
			}
			unblockRead := c.readData.p != nil
			c.readData.p = nil
			c.L.Unlock()
			if unblockRead {
				c.readData.Done()
			}

			// send SHUTDOWN-COMPLETE
			p := NewPacket(4)
			p.D[0] = byte(PacketShutdownComplete)
			copy(p.D[1:4], cd.ConnectionTag[:])
			pc.WriteTo(p.D, c.addr)

			return connectionClosed
		}

		if timerAborted {
			return connectionAbort
		}

		// process incoming data
		err := cd.Process(pc, c.addr, tq, incoming, nil)
		for _, p := range incoming {
			p.Free()
		}
		incoming = incoming[:0]
		if err != nil {
			c.L.Lock()
			c.ReadErr = err
			c.WriteErr = err
			c.L.Unlock()
			return connectionAbort
		}

		// deliver application data
		c.deliverApplicationData(cd)
	}
}
Example #22
0
func Main(clusterName, self, buri, rwsk, rosk string, cl *doozer.Conn, udpConn net.PacketConn, listener, webListener net.Listener, pulseInterval, fillDelay, kickTimeout int64, hi int64) {
	listenAddr := listener.Addr().String()

	canWrite := make(chan bool, 1)
	in := make(chan consensus.Packet, 50)
	out := make(chan consensus.Packet, 50)

	st := store.New()
	pr := &proposer{
		seqns: make(chan int64, alpha),
		props: make(chan *consensus.Prop),
		st:    st,
	}

	calSrv := func(start int64) {
		go gc.Pulse(self, st.Seqns, pr, pulseInterval)
		go gc.Clean(st, hi, time.Tick(1e9))
		var m consensus.Manager
		m.Self = self
		m.DefRev = start
		m.Alpha = alpha
		m.In = in
		m.Out = out
		m.Ops = st.Ops
		m.PSeqn = pr.seqns
		m.Props = pr.props
		m.TFill = fillDelay
		m.Store = st
		m.Ticker = time.Tick(10e6)
		go m.Run()
	}

	if cl == nil { // we are the only node in a new cluster
		set(st, "/ctl/name", clusterName, store.Missing)
		set(st, "/ctl/node/"+self+"/addr", listenAddr, store.Missing)
		set(st, "/ctl/node/"+self+"/hostname", os.Getenv("HOSTNAME"), store.Missing)
		set(st, "/ctl/node/"+self+"/version", Version, store.Missing)
		set(st, "/ctl/cal/0", self, store.Missing)
		calSrv(<-st.Seqns)
		// Skip ahead alpha steps so that the registrar can provide a
		// meaningful cluster.
		for i := 0; i < alpha; i++ {
			st.Ops <- store.Op{1 + <-st.Seqns, store.Nop}
		}
		canWrite <- true
	} else {
		setC(cl, "/ctl/node/"+self+"/addr", listenAddr, store.Clobber)
		setC(cl, "/ctl/node/"+self+"/hostname", os.Getenv("HOSTNAME"), store.Clobber)
		setC(cl, "/ctl/node/"+self+"/version", Version, store.Clobber)

		rev, err := cl.Rev()
		if err != nil {
			panic(err)
		}

		stop := make(chan bool, 1)
		go follow(st, cl, rev+1, stop)

		errs := make(chan os.Error)
		go func() {
			e, ok := <-errs
			if ok {
				panic(e)
			}
		}()
		doozer.Walk(cl, rev, "/", cloner{st.Ops, cl}, errs)
		close(errs)
		st.Flush()

		ch, err := st.Wait(store.Any, rev+1)
		if err == nil {
			<-ch
		}

		go func() {
			n := activate(st, self, cl)
			calSrv(n)
			advanceUntil(cl, st.Seqns, n+alpha)
			stop <- true
			canWrite <- true
			if buri != "" {
				b, err := doozer.DialUri(buri, "")
				if err != nil {
					panic(err)
				}
				setC(
					b,
					"/ctl/ns/"+clusterName+"/"+self,
					listenAddr,
					store.Missing,
				)
			}
		}()
	}

	shun := make(chan string, 3) // sufficient for a cluster of 7
	go member.Clean(shun, st, pr)
	go server.ListenAndServe(listener, canWrite, st, pr, rwsk, rosk)

	if rwsk == "" && rosk == "" && webListener != nil {
		web.Store = st
		web.ClusterName = clusterName
		go web.Serve(webListener)
	}

	go func() {
		for p := range out {
			addr, err := net.ResolveUDPAddr("udp", p.Addr)
			if err != nil {
				log.Println(err)
				continue
			}
			n, err := udpConn.WriteTo(p.Data, addr)
			if err != nil {
				log.Println(err)
				continue
			}
			if n != len(p.Data) {
				log.Println("packet len too long:", len(p.Data))
				continue
			}
		}
	}()

	lv := liveness{
		timeout: kickTimeout,
		ival:    kickTimeout / 2,
		times:   make(map[string]int64),
		self:    self,
		shun:    shun,
	}
	for {
		t := time.Nanoseconds()

		buf := make([]byte, maxUDPLen)
		n, addr, err := udpConn.ReadFrom(buf)
		if err == os.EINVAL {
			return
		}
		if err != nil {
			log.Println(err)
			continue
		}

		buf = buf[:n]

		// Update liveness time stamp for this addr
		lv.times[addr.String()] = t
		lv.check(t)

		in <- consensus.Packet{addr.String(), buf}
	}
}
Example #23
0
// receives packets from the receive loop and dispatches them
// to their corresponding connections
func processLoop(c net.PacketConn, l *listener, rld *receiveLoopData, pld *processLoopData) {

	var (
		quit        bool
		wg          = new(sync.WaitGroup)
		tq          = newTimerQueue()
		connections = struct {
			sync.RWMutex
			M map[uint32]*connection
		}{
			M: make(map[uint32]*connection),
		}
	)

	// keep a refcount to `c` for ourselves
	wg.Add(1)
	defer wg.Done()

	// wait for all pending connections, then close the socket
	go func() {
		wg.Wait()
		c.Close()
		tq.Close()
	}()

	// generate a new key for cookies
	cookieKey := make([]byte, sha1.Size)
	if _, err := crand.Read(cookieKey); err != nil {
		l.L.Lock()
		l.err = fmt.Errorf("Failed to generate cookie secret: %v", err)
		l.L.Unlock()
		l.Broadcast()
		return
	}

	sig := hmac.New(sha1.New, cookieKey)

	// generate addler32(localaddr)
	var localAddrSum [4]byte
	binary.LittleEndian.PutUint32(localAddrSum[:], adler32.Checksum([]byte(c.LocalAddr().String())))

	shouldWait := func() bool {
		waitOnConnections := pld.rejectNewConnections && pld.remainingConnections == 0
		return pld.err == nil && len(pld.Q) == 0 && !waitOnConnections
	}

	var packets []processLoopPacket

	for !quit {
		// wait for a packet to become available
		pld.L.Lock()
		for shouldWait() {
			pld.Wait()
		}
		rejectNewConnections := pld.rejectNewConnections
		pldErr := pld.err
		quit = pldErr != nil
		packets, pld.Q = pld.Q, packets[:0]
		remainingConnections := pld.remainingConnections
		pld.L.Unlock()

		if rejectNewConnections && remainingConnections == 0 {
			quit = true
		}

		// process packets
		for ii := range packets {
			buffer, addr := packets[ii].D, packets[ii].A

			switch PacketType(buffer[0]) {
			case PacketInit:
				// are we accepting new connections?
				if rejectNewConnections {
					continue
				}

				// verify length
				const MinInitPacketLength = 9
				if len(buffer) < MinInitPacketLength {
					continue
				}

				// verify protocol magic
				if !bytes.Equal(buffer[1:5], protocolMagic) {
					continue
				}

				// verify version
				if buffer[5] != version1 {
					sendAbort(c, addr, buffer[6:9])
					continue
				}

				var outgoing [32]byte
				now := time.Now()
				outgoing[0] = byte(PacketCookie)
				if _, err := crand.Read(outgoing[1:4]); err != nil {
					return
				}
				copy(outgoing[4:7], buffer[6:9])
				outgoing[7] = version1
				binary.LittleEndian.PutUint32(outgoing[8:12], uint32(now.Add(5*time.Second).Unix()+1))

				sig.Reset()
				sig.Write(outgoing[1:12])
				sig.Write(localAddrSum[:])
				sig.Sum(outgoing[1:12])
				c.WriteTo(outgoing[:], addr)

			case PacketCookieEcho:

				// are we accepting new connections
				if rejectNewConnections {
					continue
				}

				// verify length
				const CookieEchoPacketLength = 32
				if len(buffer) != CookieEchoPacketLength {
					continue
				}

				// verify signature
				sig.Reset()
				sig.Write(buffer[1:12])
				sig.Write(localAddrSum[:])
				if !hmac.Equal(sig.Sum(nil), buffer[12:]) {
					continue
				}

				// verify version
				if buffer[7] != version1 {
					sendAbort(c, addr, buffer[1:4])
					continue
				}

				// vetify timeout
				now := time.Now()
				if time.Unix(int64(binary.LittleEndian.Uint32(buffer[8:12])), 0).Before(now) {
					sendAbort(c, addr, buffer[1:4])
					continue
				}

				// decode connection tag to uin32
				tagId := binary.LittleEndian.Uint32(buffer[3:7]) >> 8

				connections.RLock()
				_, ok := connections.M[tagId]
				connections.RUnlock()
				// create new connection
				if !ok {

					// create connection
					wg.Add(1)
					connections.Lock()
					conn := newConnection(c, addr, tq, buffer[1:4], func() {
						connections.Lock()
						delete(connections.M, tagId)
						connections.Unlock()

						wg.Done()

						pld.L.Lock()
						pld.remainingConnections--
						remain := pld.remainingConnections
						pld.L.Unlock()

						if remain == 0 {
							pld.Signal()
						}
					})

					connections.M[tagId] = conn
					connections.Unlock()

					pld.L.Lock()
					pld.remainingConnections++
					pld.L.Unlock()

					l.L.Lock()
					l.pending = append(l.pending, conn)
					l.L.Unlock()
					l.Signal()
				}

				// send COOKIE-ACK
				var outgoing [4]byte
				outgoing[0] = byte(PacketCookieAck)
				copy(outgoing[1:4], buffer[1:4])
				c.WriteTo(outgoing[:], addr)

			default:
				// parse connection tag
				tagId := binary.LittleEndian.Uint32(buffer[0:4]) >> 8
				connections.RLock()
				conn, ok := connections.M[tagId]
				connections.RUnlock()

				// discard packets addressed to unknown connections
				if !ok {
					sendAbort(c, addr, buffer[1:4])
					continue
				}

				// copy the packet data so we can reuse the buffer
				p := NewPacket(len(buffer))
				copy(p.D, buffer)

				// queue the packet onto the connection
				conn.L.Lock()
				conn.Incoming = append(conn.Incoming, p)
				conn.L.Unlock()
				conn.Signal()
			}
		}

		// return the packet to the receive loop
		rld.L.Lock()
		for ii := range packets {
			rld.buffers = append(rld.buffers, packets[ii].D)
		}
		rld.L.Unlock()
		rld.Signal()

		// if we were signaled to quit, terminate existing connections
		if pldErr != nil {
			connections.Lock()
			m := connections.M
			connections.M = make(map[uint32]*connection)
			connections.Unlock()

			for _, c := range m {
				c.closeWithError(pldErr)
			}
		}
	}
}
Example #24
0
func Main(clusterName, self, baddr string, cl *doozer.Client, udpConn net.PacketConn, listener, webListener net.Listener, pulseInterval, fillDelay, kickTimeout int64) {
	listenAddr := listener.Addr().String()

	var activateSeqn int64
	useSelf := make(chan bool, 1)

	st := store.New()
	pr := &proposer{
		seqns: make(chan int64, alpha),
		props: make(chan *consensus.Prop),
		st:    st,
	}

	calSrv := func() {
		go gc.Pulse(self, st.Seqns, pr, pulseInterval)
		go gc.Clean(st, 360000, time.Tick(1e9))
	}

	if cl == nil { // we are the only node in a new cluster
		set(st, "/ctl/name", clusterName, store.Missing)
		set(st, "/ctl/node/"+self+"/addr", listenAddr, store.Missing)
		set(st, "/ctl/node/"+self+"/hostname", os.Getenv("HOSTNAME"), store.Missing)
		set(st, "/ctl/node/"+self+"/version", Version, store.Missing)
		set(st, "/ctl/cal/0", self, store.Missing)
		calSrv()
		close(useSelf)
	} else {
		setC(cl, "/ctl/node/"+self+"/addr", listenAddr, store.Clobber)
		setC(cl, "/ctl/node/"+self+"/hostname", os.Getenv("HOSTNAME"), store.Clobber)
		setC(cl, "/ctl/node/"+self+"/version", Version, store.Clobber)

		rev, err := cl.Rev()
		if err != nil {
			panic(err)
		}

		walk, err := cl.Walk("/**", &rev, nil, nil)
		if err != nil {
			panic(err)
		}

		watch, err := cl.Watch("/**", rev+1)
		if err != nil {
			panic(err)
		}

		go follow(st.Ops, watch.C)
		follow(st.Ops, walk.C)
		st.Flush()
		ch, err := st.Wait(rev + 1)
		if err == nil {
			<-ch
		}

		go func() {
			activateSeqn = activate(st, self, cl)
			calSrv()
			advanceUntil(cl, st.Seqns, activateSeqn+alpha)
			err := watch.Cancel()
			if err != nil {
				panic(err)
			}
			close(useSelf)
			if baddr != "" {
				b := doozer.New("<boot>", baddr)
				setC(
					b,
					"/ctl/ns/"+clusterName+"/"+self,
					listenAddr,
					store.Missing,
				)
			}
		}()
	}

	start := <-st.Seqns
	cmw := st.Watch(store.Any)
	in := make(chan consensus.Packet, 50)
	out := make(chan consensus.Packet, 50)

	consensus.NewManager(self, start, alpha, in, out, st.Ops, pr.seqns, pr.props, cmw, fillDelay, st)

	if cl == nil {
		// Skip ahead alpha steps so that the registrar can provide a
		// meaningful cluster.
		for i := start + 1; i < start+alpha+1; i++ {
			st.Ops <- store.Op{i, store.Nop}
		}
	}

	shun := make(chan string, 3) // sufficient for a cluster of 7

	go member.Clean(shun, st, pr)

	sv := &server.Server{listenAddr, st, pr, self, alpha}

	go sv.Serve(listener, useSelf)

	if webListener != nil {
		web.Store = st
		web.ClusterName = clusterName
		go web.Serve(webListener)
	}

	go func() {
		for p := range out {
			addr, err := net.ResolveUDPAddr(p.Addr)
			if err != nil {
				log.Println(err)
				continue
			}
			n, err := udpConn.WriteTo(p.Data, addr)
			if err != nil {
				log.Println(err)
				continue
			}
			if n != len(p.Data) {
				log.Println("packet len too long:", len(p.Data))
				continue
			}
		}
	}()

	lv := liveness{
		timeout: kickTimeout,
		ival:    kickTimeout / 2,
		times:   make(map[string]int64),
		self:    self,
		shun:    shun,
	}
	for {
		t := time.Nanoseconds()

		buf := make([]byte, maxUDPLen)
		n, addr, err := udpConn.ReadFrom(buf)
		if err == os.EINVAL {
			return
		}
		if err != nil {
			log.Println(err)
			continue
		}

		buf = buf[:n]

		// Update liveness time stamp for this addr
		lv.times[addr.String()] = t
		lv.check(t)

		in <- consensus.Packet{addr.String(), buf}
	}
}