2 GoVPN -- simple secure free software virtual private network daemon
3 Copyright (C) 2014-2016 Sergey Matveev <stargrave@stargrave.org>
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.
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.
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/>.
25 "cypherpunks.ru/govpn"
28 type UDPSender struct {
33 func (c UDPSender) Write(data []byte) (int, error) {
34 return c.conn.WriteToUDP(data, c.addr)
38 // Buffers for UDP parallel processing
39 udpBufs chan []byte = make(chan []byte, 1<<8)
43 bind, err := net.ResolveUDPAddr("udp", *bindAddr)
45 log.Fatalln("Can not resolve bind address:", err)
47 conn, err := net.ListenUDP("udp", bind)
49 log.Fatalln("Can not listen on UDP:", err)
51 log.Println("Listening on UDP:" + *bindAddr)
52 govpn.Println("Listening on UDP:" + *bindAddr)
54 udpBufs <- make([]byte, govpn.MTUMax)
57 var raddr *net.UDPAddr
62 var hs *govpn.Handshake
65 var peerId *govpn.PeerId
67 var conf *govpn.PeerConf
70 n, raddr, err = conn.ReadFromUDP(buf)
72 govpn.Println("Unexpected error when receiving", err)
78 ps, exists = peers[addr]
83 go func(ps *govpn.Peer, tap *govpn.TAP, buf []byte, n int) {
84 peer.PktProcess(buf[:n], tap, true)
86 }(ps.peer, ps.tap, buf, n)
90 hs, exists = handshakes[addr]
95 peer = hs.Server(buf[:n])
100 govpn.Println("Peer handshake finished:", addr, peer.Id.String())
103 delete(handshakes, addr)
107 udpBufs <- make([]byte, govpn.MTUMax)
108 udpBufs <- make([]byte, govpn.MTUMax)
110 peersByIdLock.RLock()
111 addrPrev, exists = peersById[*peer.Id]
112 peersByIdLock.RUnlock()
115 peers[addrPrev].terminator <- struct{}{}
118 tap: peers[addrPrev].tap,
119 terminator: make(chan struct{}),
121 go func(ps PeerState) {
128 delete(peers, addrPrev)
129 delete(knownPeers, addrPrev)
131 knownPeers[addr] = &peer
132 peersById[*peer.Id] = addr
134 peersByIdLock.Unlock()
136 govpn.Println("Rehandshake processed:", peer.Id.String())
138 go func(addr string, peer *govpn.Peer) {
139 ifaceName, err := callUp(peer.Id, peer.Addr)
143 tap, err := govpn.TAPListen(ifaceName, peer.MTU)
145 govpn.Println("Unable to create TAP:", err)
151 terminator: make(chan struct{}),
153 go func(ps PeerState) {
162 knownPeers[addr] = &peer
163 peersById[*peer.Id] = addr
165 peersByIdLock.Unlock()
167 govpn.Println("Peer created:", peer.Id.String())
172 peerId = idsCache.Find(buf[:n])
174 govpn.Println("Unknown identity from:", addr)
177 conf = confs[*peerId]
179 govpn.Println("Unable to get peer configuration:", peerId.String())
182 hs = govpn.NewHandshake(
184 UDPSender{conn: conn, addr: raddr},
189 handshakes[addr] = hs