2 GoVPN -- simple secure free software virtual private network daemon
3 Copyright (C) 2014-2015 Sergey Matveev <stargrave@stargrave.org>
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation, either version 3 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>.
19 // Simple secure free software virtual private network daemon.
36 bindAddr = flag.String("bind", "[::]:1194", "Bind to address")
37 peersPath = flag.String("peers", "peers", "Path to peers keys directory")
38 stats = flag.String("stats", "", "Enable stats retrieving on host:port")
39 mtu = flag.Int("mtu", 1452, "MTU for outgoing packets")
40 nonceDiff = flag.Int("noncediff", 1, "Allow nonce difference")
41 timeoutP = flag.Int("timeout", 60, "Timeout seconds")
42 noisy = flag.Bool("noise", false, "Enable noise appending")
43 cpr = flag.Int("cpr", 0, "Enable constant KiB/s out traffic rate")
46 type PeerReadyEvent struct {
51 type PeerState struct {
56 terminate chan struct{}
59 func NewPeerState(peer *govpn.Peer, iface string) *PeerState {
60 tap, sink, ready, terminate, err := govpn.TAPListen(iface)
62 log.Println("Unable to create Eth", err)
75 type EthEvent struct {
83 timeout := time.Second * time.Duration(*timeoutP)
85 log.SetFlags(log.Ldate | log.Lmicroseconds | log.Lshortfile)
88 govpn.Timeout = timeout
89 govpn.Noncediff = *nonceDiff
90 govpn.NoiseEnable = *noisy
92 govpn.PeersInit(*peersPath)
94 bind, err := net.ResolveUDPAddr("udp", *bindAddr)
98 conn, err := net.ListenUDP("udp", bind)
102 udpSink, udpBuf, udpReady := govpn.ConnListen(conn)
104 termSignal := make(chan os.Signal, 1)
105 signal.Notify(termSignal, os.Interrupt, os.Kill)
107 hsHeartbeat := time.Tick(timeout)
108 go func() { <-hsHeartbeat }()
111 var state *govpn.Handshake
112 var peerState *PeerState
115 states := make(map[string]*govpn.Handshake)
116 peers := make(map[string]*PeerState)
117 peerReadySink := make(chan PeerReadyEvent)
118 knownPeers := govpn.KnownPeers(make(map[string]**govpn.Peer))
119 var peerReady PeerReadyEvent
120 var udpPkt govpn.UDPPkt
121 var udpPktData []byte
122 var ethEvent EthEvent
123 var peerId *govpn.PeerId
124 var handshakeProcessForce bool
125 ethSink := make(chan EthEvent)
127 log.Println(govpn.VersionGet())
128 log.Println("Max MTU on TAP interface:", govpn.TAPMaxMTU())
130 log.Println("Stats are going to listen on", *stats)
131 statsPort, err := net.Listen("tcp", *stats)
135 go govpn.StatsProcessor(statsPort, &knownPeers)
137 log.Println("Server started")
146 for addr, hs := range states {
147 if hs.LastPing.Add(timeout).Before(now) {
148 log.Println("Deleting handshake state", addr)
153 for addr, state := range peers {
154 if state.peer.LastPing.Add(timeout).Before(now) {
155 log.Println("Deleting peer", state.peer)
157 delete(knownPeers, addr)
158 downPath := path.Join(
160 state.peer.Id.String(),
163 go govpn.ScriptCall(downPath, state.tap.Name)
164 state.terminate <- struct{}{}
168 case peerReady = <-peerReadySink:
169 for addr, state := range peers {
170 if state.tap.Name != peerReady.iface {
174 delete(knownPeers, addr)
175 state.terminate <- struct{}{}
179 addr = peerReady.peer.Addr.String()
180 state := NewPeerState(peerReady.peer, peerReady.iface)
185 knownPeers[addr] = &peerReady.peer
188 log.Println("Registered interface", peerReady.iface, "with peer", peer)
189 go func(state *PeerState) {
190 for data := range state.sink {
198 case ethEvent = <-ethSink:
199 if s, exists := peers[ethEvent.peer.Addr.String()]; !exists || s.peer != ethEvent.peer {
202 ethEvent.peer.EthProcess(ethEvent.data, conn, ethEvent.ready)
203 case udpPkt = <-udpSink:
204 if udpPkt.Addr == nil {
205 udpReady <- struct{}{}
208 udpPktData = udpBuf[:udpPkt.Size]
209 addr = udpPkt.Addr.String()
210 handshakeProcessForce = false
212 if _, exists = peers[addr]; handshakeProcessForce || !exists {
213 peerId = govpn.IDsCache.Find(udpPktData)
215 log.Println("Unknown identity from", addr)
216 udpReady <- struct{}{}
219 state, exists = states[addr]
221 state = govpn.HandshakeNew(udpPkt.Addr)
224 peer = state.Server(peerId, conn, udpPktData)
226 log.Println("Peer handshake finished", peer)
227 if _, exists = peers[addr]; exists {
229 peerReadySink <- PeerReadyEvent{peer, peers[addr].tap.Name}
233 upPath := path.Join(govpn.PeersPath, peer.Id.String(), "up.sh")
234 result, err := govpn.ScriptCall(upPath, "")
238 sepIndex := bytes.Index(result, []byte{'\n'})
240 sepIndex = len(result)
242 ifaceName := string(result[:sepIndex])
243 peerReadySink <- PeerReadyEvent{peer, ifaceName}
247 if !handshakeProcessForce {
248 udpReady <- struct{}{}
252 peerState, exists = peers[addr]
254 udpReady <- struct{}{}
257 // If it fails during processing, then try to work with it
258 // as with handshake packet
259 if !peerState.peer.UDPProcess(udpPktData, peerState.tap, udpReady) {
260 handshakeProcessForce = true
261 goto HandshakeProcess