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 nonceDiff = flag.Int("noncediff", 1, "Allow nonce difference")
43 timeoutP = flag.Int("timeout", 60, "Timeout seconds")
44 noisy = flag.Bool("noise", false, "Enable noise appending")
45 cpr = flag.Int("cpr", 0, "Enable constant KiB/sec out traffic rate")
52 log.SetFlags(log.Ldate | log.Lmicroseconds | log.Lshortfile)
56 id, err := govpn.IDDecode(*IDRaw)
61 pub, priv := govpn.NewVerifier(id, govpn.StringFromFile(*keyPath))
62 conf := &govpn.PeerConf{
64 Timeout: time.Second * time.Duration(timeout),
65 Noncediff: *nonceDiff,
71 govpn.PeersInitDummy(id, conf)
73 bind, err := net.ResolveUDPAddr("udp", "0.0.0.0:0")
75 log.Fatalln("Can not resolve address:", err)
77 conn, err := net.ListenUDP("udp", bind)
79 log.Fatalln("Can not listen on UDP:", err)
81 remote, err := net.ResolveUDPAddr("udp", *remoteAddr)
83 log.Fatalln("Can not resolve remote address:", err)
86 tap, ethSink, ethReady, _, err := govpn.TAPListen(
88 time.Second*time.Duration(timeout),
92 log.Fatalln("Can not listen on TAP interface:", err)
94 udpSink, udpBuf, udpReady := govpn.ConnListen(conn)
100 var udpPkt govpn.UDPPkt
101 var udpPktData []byte
102 knownPeers := govpn.KnownPeers(map[string]**govpn.Peer{remote.String(): &peer})
104 log.Println(govpn.VersionGet())
105 log.Println("Max MTU on TAP interface:", govpn.TAPMaxMTU())
107 log.Println("Stats are going to listen on", *stats)
108 statsPort, err := net.Listen("tcp", *stats)
110 log.Fatalln("Can not listen on stats port:", err)
112 go govpn.StatsProcessor(statsPort, &knownPeers)
115 termSignal := make(chan os.Signal, 1)
116 signal.Notify(termSignal, os.Interrupt, os.Kill)
118 log.Println("Starting handshake")
119 handshake := govpn.HandshakeStart(conf, conn, remote)
123 if peer != nil && (peer.BytesIn+peer.BytesOut) > govpn.MaxBytesPerKey {
126 handshake = govpn.HandshakeStart(conf, conn, remote)
127 log.Println("Rehandshaking")
132 case ethPkt = <-ethSink:
135 ethReady <- struct{}{}
139 peer.EthProcess(ethPkt, conn, ethReady)
140 case udpPkt = <-udpSink:
142 if timeouts >= timeout {
145 if udpPkt.Addr == nil {
146 udpReady <- struct{}{}
150 udpPktData = udpBuf[:udpPkt.Size]
152 if udpPkt.Addr.String() != remote.String() {
153 udpReady <- struct{}{}
154 log.Println("Unknown handshake message")
157 if govpn.IDsCache.Find(udpPktData) == nil {
158 log.Println("Invalid identity in handshake packet")
159 udpReady <- struct{}{}
162 if p := handshake.Client(conn, udpPktData); p != nil {
163 log.Println("Handshake completed")
165 go govpn.ScriptCall(*upPath, *ifaceName)
172 udpReady <- struct{}{}
176 udpReady <- struct{}{}
179 if peer.UDPProcess(udpPktData, tap, udpReady) {
184 govpn.ScriptCall(*downPath, *ifaceName)