cmd/govpn-server/main.go

   1 /*
   2 GoVPN -- simple secure free software virtual private network daemon
   3 Copyright (C) 2014-2020 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, version 3 of the License.
   8
   9 This program is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 GNU General Public License for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18 // Simple secure, DPI/censorship-resistant free software VPN daemon.
  19 package main
  20
  21 import (
  22         "flag"
  23         "fmt"
  24         "log"
  25         "net"
  26         "os"
  27         "os/signal"
  28         "time"
  29
  30         "go.cypherpunks.ru/govpn/v7"
  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.yaml", "Path to configuration YAML")
  37         stats    = flag.String("stats", "", "Enable stats retrieving on host:port")
  38         proxy    = flag.String("proxy", "", "Enable HTTP proxy on host:port")
  39         egdPath  = flag.String("egd", "", "Optional path to EGD socket")
  40         syslog   = flag.Bool("syslog", false, "Enable logging to syslog")
  41         version  = flag.Bool("version", false, "Print version information")
  42         warranty = flag.Bool("warranty", false, "Print warranty information")
  43 )
  44
  45 func main() {
  46         flag.Parse()
  47         if *warranty {
  48                 fmt.Println(govpn.Warranty)
  49                 return
  50         }
  51         if *version {
  52                 fmt.Println(govpn.VersionGet())
  53                 return
  54         }
  55         timeout := time.Second * time.Duration(govpn.TimeoutDefault)
  56         log.SetFlags(log.Ldate | log.Lmicroseconds | log.Lshortfile)
  57         log.Println(govpn.VersionGet())
  58
  59         confInit()
  60
  61         if *egdPath != "" {
  62                 log.Println("Using", *egdPath, "EGD")
  63                 govpn.EGDInit(*egdPath)
  64         }
  65
  66         if *syslog {
  67                 govpn.SyslogEnable()
  68         }
  69
  70         switch *proto {
  71         case "udp":
  72                 startUDP()
  73         case "tcp":
  74                 startTCP()
  75         case "all":
  76                 startUDP()
  77                 startTCP()
  78         default:
  79                 log.Fatalln("Unknown protocol specified")
  80         }
  81
  82         termSignal := make(chan os.Signal, 1)
  83         signal.Notify(termSignal, os.Interrupt, os.Kill)
  84
  85         hsHeartbeat := time.Tick(timeout)
  86         go func() { <-hsHeartbeat }()
  87
  88         if *stats != "" {
  89                 log.Println("Stats are going to listen on", *stats)
  90                 statsPort, err := net.Listen("tcp", *stats)
  91                 if err != nil {
  92                         log.Fatalln("Can not listen on stats port:", err)
  93                 }
  94                 go govpn.StatsProcessor(statsPort, &knownPeers)
  95         }
  96         if *proxy != "" {
  97                 go proxyStart()
  98         }
  99         govpn.BothPrintf(`[started bind="%s"]`, *bindAddr)
 100
 101         var needsDeletion bool
 102 MainCycle:
 103         for {
 104                 select {
 105                 case <-termSignal:
 106                         govpn.BothPrintf(`[terminating bind="%s"]`, *bindAddr)
 107                         peers.Range(func(_, psI interface{}) bool {
 108                                 ps := psI.(*PeerState)
 109                                 govpn.ScriptCall(
 110                                         confs[*ps.peer.ID].Down,
 111                                         ps.tap.Name,
 112                                         ps.peer.Addr,
 113                                 )
 114                                 return true
 115                         })
 116                         break MainCycle
 117                 case <-hsHeartbeat:
 118                         now := time.Now()
 119
 120                         handshakes.Range(func(addrI, hsI interface{}) bool {
 121                                 addr := addrI.(string)
 122                                 hs := hsI.(*govpn.Handshake)
 123                                 if hs.LastPing.Add(timeout).Before(now) {
 124                                         govpn.Printf(`[handshake-delete bind="%s" addr="%s"]`, *bindAddr, addr)
 125                                         hs.Zero()
 126                                         handshakes.Delete(addr)
 127                                 }
 128                                 return true
 129                         })
 130
 131                         peers.Range(func(addrI, psI interface{}) bool {
 132                                 addr := addrI.(string)
 133                                 ps := psI.(*PeerState)
 134                                 ps.peer.BusyR.Lock()
 135                                 needsDeletion = ps.peer.LastPing.Add(timeout).Before(now)
 136                                 ps.peer.BusyR.Unlock()
 137                                 if needsDeletion {
 138                                         govpn.Printf(
 139                                                 `[peer-delete bind="%s" peer="%s"]`,
 140                                                 *bindAddr,
 141                                                 ps.peer.ID.String(),
 142                                         )
 143                                         peers.Delete(addr)
 144                                         knownPeers.Delete(addr)
 145                                         peersByID.Delete(*ps.peer.ID)
 146                                         go govpn.ScriptCall(
 147                                                 confs[*ps.peer.ID].Down,
 148                                                 ps.tap.Name,
 149                                                 ps.peer.Addr,
 150                                         )
 151                                         ps.terminator <- struct{}{}
 152                                 }
 153                                 return true
 154                         })
 155                 }
 156         }
 157 }