src/govpn/cmd/govpn-server/main.go

   1 /*
   2 GoVPN -- simple secure free software virtual private network daemon
   3 Copyright (C) 2014-2016 Sergey Matveev <stargrave@stargrave.org>
   4
   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.
   9
  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.
  14
  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/>.
  17 */
  18
  19 // Simple secure, DPI/censorship-resistant free software VPN daemon.
  20 package main
  21
  22 import (
  23         "flag"
  24         "log"
  25         "net"
  26         "os"
  27         "os/signal"
  28         "time"
  29
  30         "govpn"
  31 )
  32
  33 var (
  34         bindAddr = flag.String("bind", "[::]:1194", "Bind to address")
  35         proto    = flag.String("proto", "udp", "Protocol to use: udp, tcp or all")
  36         confPath = flag.String("conf", "peers.json", "Path to configuration JSON")
  37         stats    = flag.String("stats", "", "Enable stats retrieving on host:port")
  38         proxy    = flag.String("proxy", "", "Enable HTTP proxy on host:port")
  39         mtu      = flag.Int("mtu", 1452, "MTU for outgoing packets")
  40         egdPath  = flag.String("egd", "", "Optional path to EGD socket")
  41 )
  42
  43 func main() {
  44         flag.Parse()
  45         timeout := time.Second * time.Duration(govpn.TimeoutDefault)
  46         log.SetFlags(log.Ldate | log.Lmicroseconds | log.Lshortfile)
  47         log.Println(govpn.VersionGet())
  48
  49         govpn.MTU = *mtu
  50         confInit()
  51         knownPeers = govpn.KnownPeers(make(map[string]**govpn.Peer))
  52
  53         if *egdPath != "" {
  54                 log.Println("Using", *egdPath, "EGD")
  55                 govpn.EGDInit(*egdPath)
  56         }
  57
  58         switch *proto {
  59         case "udp":
  60                 startUDP()
  61         case "tcp":
  62                 startTCP()
  63         case "all":
  64                 startUDP()
  65                 startTCP()
  66         default:
  67                 log.Fatalln("Unknown protocol specified")
  68         }
  69
  70         termSignal := make(chan os.Signal, 1)
  71         signal.Notify(termSignal, os.Interrupt, os.Kill)
  72
  73         hsHeartbeat := time.Tick(timeout)
  74         go func() { <-hsHeartbeat }()
  75
  76         log.Println("Max MTU on TAP interface:", govpn.TAPMaxMTU())
  77         if *stats != "" {
  78                 log.Println("Stats are going to listen on", *stats)
  79                 statsPort, err := net.Listen("tcp", *stats)
  80                 if err != nil {
  81                         log.Fatalln("Can not listen on stats port:", err)
  82                 }
  83                 go govpn.StatsProcessor(statsPort, &knownPeers)
  84         }
  85         if *proxy != "" {
  86                 go proxyStart()
  87         }
  88         log.Println("Server started")
  89
  90         var needsDeletion bool
  91 MainCycle:
  92         for {
  93                 select {
  94                 case <-termSignal:
  95                         break MainCycle
  96                 case <-hsHeartbeat:
  97                         now := time.Now()
  98                         hsLock.Lock()
  99                         for addr, hs := range handshakes {
 100                                 if hs.LastPing.Add(timeout).Before(now) {
 101                                         log.Println("Deleting handshake state", addr)
 102                                         hs.Zero()
 103                                         delete(handshakes, addr)
 104                                 }
 105                         }
 106                         peersLock.Lock()
 107                         peersByIdLock.Lock()
 108                         kpLock.Lock()
 109                         for addr, ps := range peers {
 110                                 ps.peer.BusyR.Lock()
 111                                 needsDeletion = ps.peer.LastPing.Add(timeout).Before(now)
 112                                 ps.peer.BusyR.Unlock()
 113                                 if needsDeletion {
 114                                         log.Println("Deleting peer", ps.peer)
 115                                         delete(peers, addr)
 116                                         delete(knownPeers, addr)
 117                                         delete(peersById, *ps.peer.Id)
 118                                         go govpn.ScriptCall(
 119                                                 confs[*ps.peer.Id].Down,
 120                                                 ps.tap.Name,
 121                                         )
 122                                         ps.terminator <- struct{}{}
 123                                 }
 124                         }
 125                         hsLock.Unlock()
 126                         peersLock.Unlock()
 127                         peersByIdLock.Unlock()
 128                         kpLock.Unlock()
 129                 }
 130         }
 131 }