--- /dev/null
+/*
+GoVPN -- simple secure free software virtual private network daemon
+Copyright (C) 2014-2016 Sergey Matveev <stargrave@stargrave.org>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package client
+
+import (
+ "bytes"
+ "fmt"
+ "net"
+ "sync/atomic"
+ "time"
+
+ "cypherpunks.ru/govpn"
+)
+
+func (c *Client) startTCP() {
+ remote, err := net.ResolveTCPAddr("tcp", c.config.RemoteAddress)
+ if err != nil {
+ c.Error <- fmt.Errorf("Can not resolve remote address: %s", err)
+ return
+ }
+ conn, err := net.DialTCP("tcp", nil, remote)
+ if err != nil {
+ c.Error <- fmt.Errorf("Can not connect to address: %s", err)
+ return
+ }
+ govpn.Printf(`[connected remote="%s"]`, c.config.RemoteAddress)
+ c.handleTCP(conn)
+}
+
+func (c *Client) handleTCP(conn *net.TCPConn) {
+ hs := govpn.HandshakeStart(c.config.RemoteAddress, conn, c.config.Peer)
+ buf := make([]byte, 2*(govpn.EnclessEnlargeSize+c.config.MTU)+c.config.MTU)
+ var n int
+ var err error
+ var prev int
+ var peer *govpn.Peer
+ var terminator chan struct{}
+HandshakeCycle:
+ for {
+ select {
+ case <-c.termination:
+ break HandshakeCycle
+ default:
+ }
+ if prev == len(buf) {
+ govpn.Printf(`[packet-timeouted remote="%s"]`, c.config.RemoteAddress)
+ c.timeouted <- struct{}{}
+ break HandshakeCycle
+ }
+
+ if err = conn.SetReadDeadline(time.Now().Add(c.config.Peer.Timeout)); err != nil {
+ c.Error <- err
+ break HandshakeCycle
+ }
+ n, err = conn.Read(buf[prev:])
+ if err != nil {
+ govpn.Printf(`[connection-timeouted remote="%s"]`, c.config.RemoteAddress)
+ c.timeouted <- struct{}{}
+ break HandshakeCycle
+ }
+
+ prev += n
+ peerId := c.idsCache.Find(buf[:prev])
+ if peerId == nil {
+ continue
+ }
+ peer = hs.Client(buf[:prev])
+ prev = 0
+ if peer == nil {
+ continue
+ }
+ govpn.Printf(`[handshake-completed remote="%s"]`, c.config.RemoteAddress)
+ c.knownPeers = govpn.KnownPeers(map[string]**govpn.Peer{c.config.RemoteAddress: &peer})
+ if c.firstUpCall {
+ go govpn.ScriptCall(c.config.UpPath, c.config.InterfaceName, c.config.RemoteAddress)
+ c.firstUpCall = false
+ }
+ hs.Zero()
+ terminator = make(chan struct{})
+ go govpn.PeerTapProcessor(peer, c.tap, terminator)
+ break HandshakeCycle
+ }
+ if hs != nil {
+ hs.Zero()
+ }
+ if peer == nil {
+ return
+ }
+
+ prev = 0
+ var i int
+TransportCycle:
+ for {
+ select {
+ case <-c.termination:
+ break TransportCycle
+ default:
+ }
+ if prev == len(buf) {
+ govpn.Printf(`[packet-timeouted remote="%s"]`, c.config.RemoteAddress)
+ c.timeouted <- struct{}{}
+ break TransportCycle
+ }
+ if err = conn.SetReadDeadline(time.Now().Add(c.config.Peer.Timeout)); err != nil {
+ c.Error <- err
+ break TransportCycle
+ }
+ n, err = conn.Read(buf[prev:])
+ if err != nil {
+ govpn.Printf(`[connection-timeouted remote="%s"]`, c.config.RemoteAddress)
+ c.timeouted <- struct{}{}
+ break TransportCycle
+ }
+ prev += n
+ CheckMore:
+ if prev < govpn.MinPktLength {
+ continue
+ }
+ i = bytes.Index(buf[:prev], peer.NonceExpect)
+ if i == -1 {
+ continue
+ }
+ if !peer.PktProcess(buf[:i+govpn.NonceSize], c.tap, false) {
+ govpn.Printf(`[packet-unauthenticated remote="%s"]`, c.config.RemoteAddress)
+ c.timeouted <- struct{}{}
+ break TransportCycle
+ }
+ if atomic.LoadUint64(&peer.BytesIn)+atomic.LoadUint64(&peer.BytesOut) > govpn.MaxBytesPerKey {
+ govpn.Printf(`[rehandshake-required remote="%s"]`, c.config.RemoteAddress)
+ c.rehandshaking <- struct{}{}
+ break TransportCycle
+ }
+ copy(buf, buf[i+govpn.NonceSize:prev])
+ prev = prev - i - govpn.NonceSize
+ goto CheckMore
+ }
+ if terminator != nil {
+ terminator <- struct{}{}
+ }
+ peer.Zero()
+ if err = conn.Close(); err != nil {
+ c.Error <- err
+ }
+}