src/govpn/cmd/govpn-client/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 client.
  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         remoteAddr = flag.String("remote", "", "Remote server address")
  35         proto      = flag.String("proto", "udp", "Protocol to use: udp or tcp")
  36         ifaceName  = flag.String("iface", "tap0", "TAP network interface")
  37         IDRaw      = flag.String("id", "", "Client identification")
  38         keyPath    = flag.String("key", "", "Path to passphrase file")
  39         upPath     = flag.String("up", "", "Path to up-script")
  40         downPath   = flag.String("down", "", "Path to down-script")
  41         stats      = flag.String("stats", "", "Enable stats retrieving on host:port")
  42         proxyAddr  = flag.String("proxy", "", "Use HTTP proxy on host:port")
  43         proxyAuth  = flag.String("proxy-auth", "", "user:password Basic proxy auth")
  44         mtu        = flag.Int("mtu", 1452, "MTU for outgoing packets")
  45         timeoutP   = flag.Int("timeout", 60, "Timeout seconds")
  46         noisy      = flag.Bool("noise", false, "Enable noise appending")
  47         cpr        = flag.Int("cpr", 0, "Enable constant KiB/sec out traffic rate")
  48         egdPath    = flag.String("egd", "", "Optional path to EGD socket")
  49
  50         conf        *govpn.PeerConf
  51         tap         *govpn.TAP
  52         timeout     int
  53         firstUpCall bool = true
  54         knownPeers  govpn.KnownPeers
  55         idsCache    govpn.CipherCache
  56 )
  57
  58 func main() {
  59         flag.Parse()
  60         timeout = *timeoutP
  61         var err error
  62         log.SetFlags(log.Ldate | log.Lmicroseconds | log.Lshortfile)
  63
  64         govpn.MTU = *mtu
  65
  66         id, err := govpn.IDDecode(*IDRaw)
  67         if err != nil {
  68                 log.Fatalln(err)
  69         }
  70
  71         if *egdPath != "" {
  72                 log.Println("Using", *egdPath, "EGD")
  73                 govpn.EGDInit(*egdPath)
  74         }
  75
  76         pub, priv := govpn.NewVerifier(id, govpn.StringFromFile(*keyPath))
  77         conf = &govpn.PeerConf{
  78                 Id:      id,
  79                 Timeout: time.Second * time.Duration(timeout),
  80                 Noise:   *noisy,
  81                 CPR:     *cpr,
  82                 DSAPub:  pub,
  83                 DSAPriv: priv,
  84         }
  85         idsCache = govpn.NewCipherCache([]govpn.PeerId{*id})
  86         log.Println(govpn.VersionGet())
  87
  88         tap, err = govpn.TAPListen(*ifaceName)
  89         if err != nil {
  90                 log.Fatalln("Can not listen on TAP interface:", err)
  91         }
  92
  93         log.Println("Max MTU on TAP interface:", govpn.TAPMaxMTU())
  94         if *stats != "" {
  95                 log.Println("Stats are going to listen on", *stats)
  96                 statsPort, err := net.Listen("tcp", *stats)
  97                 if err != nil {
  98                         log.Fatalln("Can not listen on stats port:", err)
  99                 }
 100                 go govpn.StatsProcessor(statsPort, &knownPeers)
 101         }
 102
 103         termSignal := make(chan os.Signal, 1)
 104         signal.Notify(termSignal, os.Interrupt, os.Kill)
 105
 106 MainCycle:
 107         for {
 108                 timeouted := make(chan struct{})
 109                 rehandshaking := make(chan struct{})
 110                 termination := make(chan struct{})
 111                 if *proxyAddr != "" {
 112                         *proto = "tcp"
 113                 }
 114                 switch *proto {
 115                 case "udp":
 116                         go startUDP(timeouted, rehandshaking, termination)
 117                 case "tcp":
 118                         if *proxyAddr != "" {
 119                                 go proxyTCP(timeouted, rehandshaking, termination)
 120                         } else {
 121                                 go startTCP(timeouted, rehandshaking, termination)
 122                         }
 123                 default:
 124                         log.Fatalln("Unknown protocol specified")
 125                 }
 126                 select {
 127                 case <-termSignal:
 128                         log.Fatalln("Finishing")
 129                         termination <- struct{}{}
 130                         break MainCycle
 131                 case <-timeouted:
 132                         break MainCycle
 133                 case <-rehandshaking:
 134                 }
 135                 close(timeouted)
 136                 close(rehandshaking)
 137                 close(termination)
 138         }
 139         govpn.ScriptCall(*downPath, *ifaceName)
 140 }