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 egdPath = flag.String("egd", "", "Optional path to EGD socket")
43 type PeerReadyEvent struct {
48 type PeerState struct {
53 terminate chan struct{}
56 func NewPeerState(peer *govpn.Peer, iface string) *PeerState {
57 tap, sink, ready, terminate, err := govpn.TAPListen(iface, peer.Timeout, peer.CPR)
59 log.Println("Unable to create Eth", err)
72 type EthEvent struct {
80 timeout := time.Second * time.Duration(govpn.TimeoutDefault)
82 log.SetFlags(log.Ldate | log.Lmicroseconds | log.Lshortfile)
85 govpn.PeersInit(*peersPath)
88 log.Println("Using", *egdPath, "EGD")
89 govpn.EGDInit(*egdPath)
92 bind, err := net.ResolveUDPAddr("udp", *bindAddr)
94 log.Fatalln("Can not resolve bind address:", err)
96 conn, err := net.ListenUDP("udp", bind)
98 log.Fatalln("Can listen on UDP:", err)
100 udpSink, udpBuf, udpReady := govpn.ConnListen(conn)
102 termSignal := make(chan os.Signal, 1)
103 signal.Notify(termSignal, os.Interrupt, os.Kill)
105 hsHeartbeat := time.Tick(timeout)
106 go func() { <-hsHeartbeat }()
109 var state *govpn.Handshake
110 var peerState *PeerState
113 states := make(map[string]*govpn.Handshake)
114 peers := make(map[string]*PeerState)
115 peerReadySink := make(chan PeerReadyEvent)
116 knownPeers := govpn.KnownPeers(make(map[string]**govpn.Peer))
117 var peerReady PeerReadyEvent
118 var udpPkt govpn.UDPPkt
119 var udpPktData []byte
120 var ethEvent EthEvent
121 var peerId *govpn.PeerId
122 var peerConf *govpn.PeerConf
123 var handshakeProcessForce bool
124 ethSink := make(chan EthEvent)
126 log.Println(govpn.VersionGet())
127 log.Println("Max MTU on TAP interface:", govpn.TAPMaxMTU())
129 log.Println("Stats are going to listen on", *stats)
130 statsPort, err := net.Listen("tcp", *stats)
132 log.Fatalln("Can not listen on stats port:", err)
134 go govpn.StatsProcessor(statsPort, &knownPeers)
136 log.Println("Server started")
145 for addr, hs := range states {
146 if hs.LastPing.Add(timeout).Before(now) {
147 log.Println("Deleting handshake state", addr)
152 for addr, state := range peers {
153 if state.peer.LastPing.Add(timeout).Before(now) {
154 log.Println("Deleting peer", state.peer)
156 delete(knownPeers, addr)
157 downPath := path.Join(
159 state.peer.Id.String(),
162 go govpn.ScriptCall(downPath, state.tap.Name)
163 state.terminate <- struct{}{}
167 case peerReady = <-peerReadySink:
168 for addr, state := range peers {
169 if state.tap.Name != peerReady.iface {
173 delete(knownPeers, addr)
174 state.terminate <- struct{}{}
178 addr = peerReady.peer.Addr.String()
179 state := NewPeerState(peerReady.peer, peerReady.iface)
184 knownPeers[addr] = &peerReady.peer
187 log.Println("Registered interface", peerReady.iface, "with peer", peer)
188 go func(state *PeerState) {
189 for data := range state.sink {
197 case ethEvent = <-ethSink:
198 if s, exists := peers[ethEvent.peer.Addr.String()]; !exists || s.peer != ethEvent.peer {
201 ethEvent.peer.EthProcess(ethEvent.data, conn, ethEvent.ready)
202 case udpPkt = <-udpSink:
203 if udpPkt.Addr == nil {
204 udpReady <- struct{}{}
207 udpPktData = udpBuf[:udpPkt.Size]
208 addr = udpPkt.Addr.String()
209 handshakeProcessForce = false
211 if _, exists = peers[addr]; handshakeProcessForce || !exists {
212 peerId = govpn.IDsCache.Find(udpPktData)
214 log.Println("Unknown identity from", addr)
215 udpReady <- struct{}{}
218 peerConf = peerId.Conf()
220 log.Println("Can not get peer configuration", peerId.String())
221 udpReady <- struct{}{}
224 state, exists = states[addr]
226 state = govpn.HandshakeNew(udpPkt.Addr, peerConf)
229 peer = state.Server(conn, udpPktData)
231 log.Println("Peer handshake finished", peer)
232 if _, exists = peers[addr]; exists {
234 peerReadySink <- PeerReadyEvent{peer, peers[addr].tap.Name}
238 upPath := path.Join(govpn.PeersPath, peer.Id.String(), "up.sh")
239 result, err := govpn.ScriptCall(upPath, "")
243 sepIndex := bytes.Index(result, []byte{'\n'})
245 sepIndex = len(result)
247 ifaceName := string(result[:sepIndex])
248 peerReadySink <- PeerReadyEvent{peer, ifaceName}
252 if !handshakeProcessForce {
253 udpReady <- struct{}{}
257 peerState, exists = peers[addr]
259 udpReady <- struct{}{}
262 // If it fails during processing, then try to work with it
263 // as with handshake packet
264 if !peerState.peer.UDPProcess(udpPktData, peerState.tap, udpReady) {
265 handshakeProcessForce = true
266 goto HandshakeProcess