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 client.
34 remoteAddr = flag.String("remote", "", "Remote server address")
35 ifaceName = flag.String("iface", "tap0", "TAP network interface")
36 IDRaw = flag.String("id", "", "Client identification")
37 keyPath = flag.String("key", "", "Path to passphrase file")
38 upPath = flag.String("up", "", "Path to up-script")
39 downPath = flag.String("down", "", "Path to down-script")
40 stats = flag.String("stats", "", "Enable stats retrieving on host:port")
41 mtu = flag.Int("mtu", 1452, "MTU for outgoing packets")
42 timeoutP = flag.Int("timeout", 60, "Timeout seconds")
43 noisy = flag.Bool("noise", false, "Enable noise appending")
44 cpr = flag.Int("cpr", 0, "Enable constant KiB/sec out traffic rate")
45 egdPath = flag.String("egd", "", "Optional path to EGD socket")
52 log.SetFlags(log.Ldate | log.Lmicroseconds | log.Lshortfile)
56 id, err := govpn.IDDecode(*IDRaw)
62 log.Println("Using", *egdPath, "EGD")
63 govpn.EGDInit(*egdPath)
66 pub, priv := govpn.NewVerifier(id, govpn.StringFromFile(*keyPath))
67 conf := &govpn.PeerConf{
69 Timeout: time.Second * time.Duration(timeout),
75 govpn.PeersInitDummy(id, conf)
77 bind, err := net.ResolveUDPAddr("udp", "0.0.0.0:0")
79 log.Fatalln("Can not resolve address:", err)
81 conn, err := net.ListenUDP("udp", bind)
83 log.Fatalln("Can not listen on UDP:", err)
85 remote, err := net.ResolveUDPAddr("udp", *remoteAddr)
87 log.Fatalln("Can not resolve remote address:", err)
90 tap, ethSink, ethReady, _, err := govpn.TAPListen(
92 time.Second*time.Duration(timeout),
96 log.Fatalln("Can not listen on TAP interface:", err)
98 udpSink, udpBuf, udpReady := govpn.ConnListen(conn)
104 var udpPkt govpn.UDPPkt
105 var udpPktData []byte
106 knownPeers := govpn.KnownPeers(map[string]**govpn.Peer{remote.String(): &peer})
108 log.Println(govpn.VersionGet())
109 log.Println("Max MTU on TAP interface:", govpn.TAPMaxMTU())
111 log.Println("Stats are going to listen on", *stats)
112 statsPort, err := net.Listen("tcp", *stats)
114 log.Fatalln("Can not listen on stats port:", err)
116 go govpn.StatsProcessor(statsPort, &knownPeers)
119 termSignal := make(chan os.Signal, 1)
120 signal.Notify(termSignal, os.Interrupt, os.Kill)
122 log.Println("Starting handshake")
123 handshake := govpn.HandshakeStart(conf, conn, remote)
127 if peer != nil && (peer.BytesIn+peer.BytesOut) > govpn.MaxBytesPerKey {
130 handshake = govpn.HandshakeStart(conf, conn, remote)
131 log.Println("Rehandshaking")
136 case ethPkt = <-ethSink:
139 ethReady <- struct{}{}
143 peer.EthProcess(ethPkt, conn, ethReady)
144 case udpPkt = <-udpSink:
146 if timeouts >= timeout {
149 if udpPkt.Addr == nil {
150 udpReady <- struct{}{}
154 udpPktData = udpBuf[:udpPkt.Size]
156 if udpPkt.Addr.String() != remote.String() {
157 udpReady <- struct{}{}
158 log.Println("Unknown handshake message")
161 if govpn.IDsCache.Find(udpPktData) == nil {
162 log.Println("Invalid identity in handshake packet")
163 udpReady <- struct{}{}
166 if p := handshake.Client(conn, udpPktData); p != nil {
167 log.Println("Handshake completed")
169 go govpn.ScriptCall(*upPath, *ifaceName)
176 udpReady <- struct{}{}
180 udpReady <- struct{}{}
183 if peer.UDPProcess(udpPktData, tap, udpReady) {
188 govpn.ScriptCall(*downPath, *ifaceName)