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         verifierRaw = flag.String("verifier", "", "Verifier")
  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         if *egdPath != "" {
  67                 log.Println("Using", *egdPath, "EGD")
  68                 govpn.EGDInit(*egdPath)
  69         }
  70
  71         verifier, err := govpn.VerifierFromString(*verifierRaw)
  72         if err != nil {
  73                 log.Fatalln(err)
  74         }
  75         priv := verifier.PasswordApply(govpn.StringFromFile(*keyPath))
  76         conf = &govpn.PeerConf{
  77                 Id:       verifier.Id,
  78                 Timeout:  time.Second * time.Duration(timeout),
  79                 Noise:    *noisy,
  80                 CPR:      *cpr,
  81                 Verifier: verifier,
  82                 DSAPriv:  priv,
  83         }
  84         idsCache = govpn.NewCipherCache([]govpn.PeerId{*verifier.Id})
  85         log.Println(govpn.VersionGet())
  86
  87         tap, err = govpn.TAPListen(*ifaceName)
  88         if err != nil {
  89                 log.Fatalln("Can not listen on TAP interface:", err)
  90         }
  91
  92         log.Println("Max MTU on TAP interface:", govpn.TAPMaxMTU())
  93         if *stats != "" {
  94                 log.Println("Stats are going to listen on", *stats)
  95                 statsPort, err := net.Listen("tcp", *stats)
  96                 if err != nil {
  97                         log.Fatalln("Can not listen on stats port:", err)
  98                 }
  99                 go govpn.StatsProcessor(statsPort, &knownPeers)
 100         }
 101
 102         termSignal := make(chan os.Signal, 1)
 103         signal.Notify(termSignal, os.Interrupt, os.Kill)
 104
 105 MainCycle:
 106         for {
 107                 timeouted := make(chan struct{})
 108                 rehandshaking := make(chan struct{})
 109                 termination := make(chan struct{})
 110                 if *proxyAddr != "" {
 111                         *proto = "tcp"
 112                 }
 113                 switch *proto {
 114                 case "udp":
 115                         go startUDP(timeouted, rehandshaking, termination)
 116                 case "tcp":
 117                         if *proxyAddr != "" {
 118                                 go proxyTCP(timeouted, rehandshaking, termination)
 119                         } else {
 120                                 go startTCP(timeouted, rehandshaking, termination)
 121                         }
 122                 default:
 123                         log.Fatalln("Unknown protocol specified")
 124                 }
 125                 select {
 126                 case <-termSignal:
 127                         log.Fatalln("Finishing")
 128                         termination <- struct{}{}
 129                         break MainCycle
 130                 case <-timeouted:
 131                         break MainCycle
 132                 case <-rehandshaking:
 133                 }
 134                 close(timeouted)
 135                 close(rehandshaking)
 136                 close(termination)
 137         }
 138         govpn.ScriptCall(*downPath, *ifaceName)
 139 }