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

   1 /*
   2 GoVPN -- simple secure free software virtual private network daemon
   3 Copyright (C) 2014-2015 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         "path"
  29         "time"
  30
  31         "govpn"
  32 )
  33
  34 var (
  35         bindAddr  = flag.String("bind", "[::]:1194", "Bind to address")
  36         proto     = flag.String("proto", "udp", "Protocol to use: udp, tcp or all")
  37         peersPath = flag.String("peers", "peers", "Path to peers keys directory")
  38         stats     = flag.String("stats", "", "Enable stats retrieving on host:port")
  39         proxy     = flag.String("proxy", "", "Enable HTTP proxy on host:port")
  40         mtu       = flag.Int("mtu", 1452, "MTU for outgoing packets")
  41         egdPath   = flag.String("egd", "", "Optional path to EGD socket")
  42 )
  43
  44 func main() {
  45         flag.Parse()
  46         timeout := time.Second * time.Duration(govpn.TimeoutDefault)
  47         log.SetFlags(log.Ldate | log.Lmicroseconds | log.Lshortfile)
  48         log.Println(govpn.VersionGet())
  49
  50         govpn.MTU = *mtu
  51         govpn.PeersInit(*peersPath)
  52         knownPeers = govpn.KnownPeers(make(map[string]**govpn.Peer))
  53
  54         if *egdPath != "" {
  55                 log.Println("Using", *egdPath, "EGD")
  56                 govpn.EGDInit(*egdPath)
  57         }
  58
  59         switch *proto {
  60         case "udp":
  61                 startUDP()
  62         case "tcp":
  63                 startTCP()
  64         case "all":
  65                 startUDP()
  66                 startTCP()
  67         default:
  68                 log.Fatalln("Unknown protocol specified")
  69         }
  70
  71         termSignal := make(chan os.Signal, 1)
  72         signal.Notify(termSignal, os.Interrupt, os.Kill)
  73
  74         hsHeartbeat := time.Tick(timeout)
  75         go func() { <-hsHeartbeat }()
  76
  77         log.Println("Max MTU on TAP interface:", govpn.TAPMaxMTU())
  78         if *stats != "" {
  79                 log.Println("Stats are going to listen on", *stats)
  80                 statsPort, err := net.Listen("tcp", *stats)
  81                 if err != nil {
  82                         log.Fatalln("Can not listen on stats port:", err)
  83                 }
  84                 go govpn.StatsProcessor(statsPort, &knownPeers)
  85         }
  86         if *proxy != "" {
  87                 go proxyStart()
  88         }
  89         log.Println("Server started")
  90
  91         var needsDeletion bool
  92 MainCycle:
  93         for {
  94                 select {
  95                 case <-termSignal:
  96                         break MainCycle
  97                 case <-hsHeartbeat:
  98                         now := time.Now()
  99                         hsLock.Lock()
 100                         for addr, hs := range handshakes {
 101                                 if hs.LastPing.Add(timeout).Before(now) {
 102                                         log.Println("Deleting handshake state", addr)
 103                                         hs.Zero()
 104                                         delete(handshakes, addr)
 105                                 }
 106                         }
 107                         peersLock.Lock()
 108                         peersByIdLock.Lock()
 109                         kpLock.Lock()
 110                         for addr, ps := range peers {
 111                                 ps.peer.BusyR.Lock()
 112                                 needsDeletion = ps.peer.LastPing.Add(timeout).Before(now)
 113                                 ps.peer.BusyR.Unlock()
 114                                 if needsDeletion {
 115                                         log.Println("Deleting peer", ps.peer)
 116                                         delete(peers, addr)
 117                                         delete(knownPeers, addr)
 118                                         delete(peersById, *ps.peer.Id)
 119                                         downPath := path.Join(
 120                                                 govpn.PeersPath,
 121                                                 ps.peer.Id.String(),
 122                                                 "down.sh",
 123                                         )
 124                                         go govpn.ScriptCall(downPath, ps.tap.Name)
 125                                         ps.terminator <- struct{}{}
 126                                 }
 127                         }
 128                         hsLock.Unlock()
 129                         peersLock.Unlock()
 130                         peersByIdLock.Unlock()
 131                         kpLock.Unlock()
 132                 }
 133         }
 134 }