2 GoVPN -- simple secure free software virtual private network daemon
3 Copyright (C) 2014-2015 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/>.
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 udpBufs <- make([]byte, govpn.MTU)
55 var raddr *net.UDPAddr
60 var hs *govpn.Handshake
63 var peerId *govpn.PeerId
65 var conf *govpn.PeerConf
69 n, raddr, err = conn.ReadFromUDP(buf)
76 ps, exists = peers[addr]
81 go func(ps *govpn.Peer, tap *govpn.TAP, buf []byte, n int) {
82 peer.PktProcess(buf[:n], tap, true)
84 }(ps.peer, ps.tap, buf, n)
88 hs, exists = handshakes[addr]
93 peer = hs.Server(buf[:n])
98 log.Println("Peer handshake finished:", addr)
101 delete(handshakes, addr)
105 udpBufs <- make([]byte, govpn.MTU)
106 udpBufs <- make([]byte, govpn.MTU)
108 peersByIdLock.RLock()
109 addrPrev, exists = peersById[*peer.Id]
110 peersByIdLock.RUnlock()
115 tap: peers[addrPrev].tap,
116 terminator: peers[addrPrev].terminator,
119 ps.terminator <- struct{}{}
123 delete(peers, addrPrev)
124 delete(knownPeers, addrPrev)
125 delete(peersById, *peer.Id)
127 knownPeers[addr] = &peer
128 peersById[*peer.Id] = addr
130 peersByIdLock.Unlock()
132 go func(ps PeerState) {
137 log.Println("Rehandshake finished:", peer.Id.String())
139 go func(addr string, peer *govpn.Peer) {
140 ifaceName, err := callUp(peer.Id)
144 tap, err := govpn.TAPListen(ifaceName)
146 log.Println("Unable to create TAP:", err)
152 terminator: make(chan struct{}, 1),
154 go func(ps PeerState) {
163 knownPeers[addr] = &peer
164 peersById[*peer.Id] = addr
166 peersByIdLock.Unlock()
168 log.Println("New peer:", peer.Id.String())
173 peerId = govpn.IDsCache.Find(buf[:n])
175 log.Println("Unknown identity from:", addr)
180 log.Println("Can not get peer configuration:", peerId.String())
183 hs = govpn.NewHandshake(
185 UDPSender{conn: conn, addr: raddr},
190 handshakes[addr] = hs