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/*
* ZeroTier One - Global Peer to Peer Ethernet
* Copyright (C) 2011-2014 ZeroTier Networks LLC
*
* 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/>.
*
* --
*
* ZeroTier may be used and distributed under the terms of the GPLv3, which
* are available at: http://www.gnu.org/licenses/gpl-3.0.html
*
* If you would like to embed ZeroTier into a commercial application or
* redistribute it in a modified binary form, please contact ZeroTier Networks
* LLC. Start here: http://www.zerotier.com/
*/
#include "Peer.hpp"
#include "Switch.hpp"
#include <algorithm>
namespace ZeroTier {
Peer::Peer() :
_lastUsed(0),
_lastUnicastFrame(0),
_lastMulticastFrame(0),
_lastAnnouncedTo(0),
_vMajor(0),
_vMinor(0),
_vRevision(0),
_latency(0) {}
Peer::Peer(const Identity &myIdentity,const Identity &peerIdentity)
throw(std::runtime_error) :
_id(peerIdentity),
_lastUsed(0),
_lastUnicastFrame(0),
_lastMulticastFrame(0),
_lastAnnouncedTo(0),
_vMajor(0),
_vMinor(0),
_vRevision(0),
_latency(0)
{
if (!myIdentity.agree(peerIdentity,_key,ZT_PEER_SECRET_KEY_LENGTH))
throw std::runtime_error("new peer identity key agreement failed");
}
void Peer::receive(
const RuntimeEnvironment *_r,
const SharedPtr<Socket> &fromSock,
const InetAddress &remoteAddr,
unsigned int hops,
uint64_t packetId,
Packet::Verb verb,
uint64_t inRePacketId,
Packet::Verb inReVerb,
uint64_t now)
{
// Update system-wide last packet receive time
*((const_cast<uint64_t *>(&(_r->timeOfLastPacketReceived)))) = now;
// Learn paths from direct packets (hops == 0)
if (!hops) {
{
Mutex::Lock _l(_lock);
bool havePath = false;
for(std::vector<Path>::iterator p(_paths.begin());p!=_paths.end();++p) {
if ((p->address() == remoteAddr)&&(p->tcp() == fromSock->tcp())) {
p->received(now);
havePath = true;
break;
}
}
if (!havePath) {
Path::Type pt = Path::PATH_TYPE_UDP;
switch(fromSock->type()) {
case Socket::ZT_SOCKET_TYPE_TCP_IN:
pt = Path::PATH_TYPE_TCP_IN;
break;
case Socket::ZT_SOCKET_TYPE_TCP_OUT:
pt = Path::PATH_TYPE_TCP_OUT;
break;
default:
break;
}
_paths.push_back(Path(remoteAddr,pt,false));
_paths.back().received(now);
}
}
// Announce multicast LIKEs to peers to whom we have a direct link
// Lock can't be locked here or it'll recurse and deadlock.
if ((now - _lastAnnouncedTo) >= ((ZT_MULTICAST_LIKE_EXPIRE / 2) - 1000)) {
_lastAnnouncedTo = now;
_r->sw->announceMulticastGroups(SharedPtr<Peer>(this));
}
}
if (verb == Packet::VERB_FRAME)
_lastUnicastFrame = now;
else if (verb == Packet::VERB_MULTICAST_FRAME)
_lastMulticastFrame = now;
}
bool Peer::send(const RuntimeEnvironment *_r,const void *data,unsigned int len,uint64_t now)
{
Mutex::Lock _l(_lock);
Path *bestNormalPath = (Path *)0;
Path *bestTcpOutPath = (Path *)0;
uint64_t bestNormalPathLastReceived = 0;
uint64_t bestTcpOutPathLastReceived = 0;
for(std::vector<Path>::iterator p(_paths.begin());p!=_paths.end();++p) {
uint64_t lr = p->lastReceived();
if (p->type() == Path::PATH_TYPE_TCP_OUT) { // TCP_OUT paths initiate TCP connections
if (lr >= bestTcpOutPathLastReceived) {
bestTcpOutPathLastReceived = lr;
bestTcpOutPath = &(*p);
}
} else { // paths other than TCP_OUT are considered "normal"
if (lr >= bestNormalPathLastReceived) {
bestNormalPathLastReceived = lr;
bestNormalPath = &(*p);
}
}
}
Path *bestPath = (Path *)0;
if (!_r->tcpTunnelingEnabled) { // TCP tunneling master switch is off, use normal path
bestPath = bestNormalPath;
} else if (bestNormalPath) { // we have a normal path, so use if it looks active
if ((bestNormalPathLastReceived > _r->timeOfLastResynchronize)&&((now - bestNormalPathLastReceived) < ZT_PEER_PATH_ACTIVITY_TIMEOUT))
bestPath = bestNormalPath;
else bestPath = bestTcpOutPath;
} else { // no normal path available
bestPath = bestTcpOutPath;
}
if (!bestPath)
return false;
if (_r->sm->send(bestPath->address(),bestPath->tcp(),bestPath->type() == Path::PATH_TYPE_TCP_OUT,data,len)) {
bestPath->sent(now);
return true;
}
return false;
}
bool Peer::sendFirewallOpener(const RuntimeEnvironment *_r,uint64_t now)
{
bool sent = false;
Mutex::Lock _l(_lock);
for(std::vector<Path>::iterator p(_paths.begin());p!=_paths.end();++p) {
if (!p->tcp())
sent |= _r->sm->sendFirewallOpener(p->address(),ZT_FIREWALL_OPENER_HOPS);
}
return sent;
}
bool Peer::sendPing(const RuntimeEnvironment *_r,uint64_t now)
{
bool sent = false;
SharedPtr<Peer> self(this);
Mutex::Lock _l(_lock);
uint64_t lastUdpPingSent = 0;
uint64_t lastUdpReceive = 0;
bool haveUdp = false;
for(std::vector<Path>::const_iterator p(_paths.begin());p!=_paths.end();++p) {
if (p->type() == Path::PATH_TYPE_UDP) {
lastUdpPingSent = std::max(lastUdpPingSent,p->lastPing());
lastUdpReceive = std::max(lastUdpReceive,p->lastReceived());
haveUdp = true;
}
}
bool useTcpOut = ( (!haveUdp) || ( (_r->tcpTunnelingEnabled) && (lastUdpPingSent > lastUdpReceive) && ((now - lastUdpReceive) >= ZT_TCP_TUNNEL_FAILOVER_TIMEOUT) ) );
TRACE("PING %s (useTcpOut==%d)",_id.address().toString().c_str(),(int)useTcpOut);
for(std::vector<Path>::iterator p(_paths.begin());p!=_paths.end();++p) {
if ((useTcpOut)||(p->type() != Path::PATH_TYPE_TCP_OUT)) {
p->pinged(now); // we log pings sent even if the send "fails", since what we want to track is when we last tried to ping
if (_r->sw->sendHELLO(self,*p)) {
p->sent(now);
sent = true;
}
}
}
return sent;
}
void Peer::clean(uint64_t now)
{
Mutex::Lock _l(_lock);
unsigned long i = 0,o = 0,l = (unsigned long)_paths.size();
while (i != l) {
if (_paths[i].active(now))
_paths[o++] = _paths[i];
++i;
}
_paths.resize(o);
}
void Peer::getBestActiveUdpPathAddresses(uint64_t now,InetAddress &v4,InetAddress &v6) const
{
uint64_t bestV4 = 0,bestV6 = 0;
Mutex::Lock _l(_lock);
for(std::vector<Path>::const_iterator p(_paths.begin());p!=_paths.end();++p) {
if ((p->type() == Path::PATH_TYPE_UDP)&&(p->active(now))) {
uint64_t lr = p->lastReceived();
if (lr) {
if (p->address().isV4()) {
if (lr >= bestV4) {
bestV4 = lr;
v4 = p->address();
}
} else if (p->address().isV6()) {
if (lr >= bestV6) {
bestV6 = lr;
v6 = p->address();
}
}
}
}
}
}
} // namespace ZeroTier
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