ZeroTierOne/node/Peer.cpp

336 lines
10 KiB
C++

/*
* ZeroTier One - Network Virtualization Everywhere
* Copyright (C) 2011-2015 ZeroTier, Inc.
*
* 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 "Constants.hpp"
#include "Peer.hpp"
#include "Switch.hpp"
#include "Packet.hpp"
#include "Network.hpp"
#include "NodeConfig.hpp"
#include "AntiRecursion.hpp"
#include <algorithm>
namespace ZeroTier {
Peer::Peer(const Identity &myIdentity,const Identity &peerIdentity)
throw(std::runtime_error) :
_lastUsed(0),
_lastReceive(0),
_lastUnicastFrame(0),
_lastMulticastFrame(0),
_lastAnnouncedTo(0),
_vMajor(0),
_vMinor(0),
_vRevision(0),
_numPaths(0),
_latency(0),
_id(peerIdentity)
{
if (!myIdentity.agree(peerIdentity,_key,ZT_PEER_SECRET_KEY_LENGTH))
throw std::runtime_error("new peer identity key agreement failed");
}
void Peer::received(
const RuntimeEnvironment *RR,
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 *>(&(RR->timeOfLastPacketReceived)))) = now;
// Global last receive time regardless of path
_lastReceive = now;
if (!hops) {
// Learn paths from direct packets (hops == 0)
{
bool havePath = false;
for(unsigned int p=0,np=_numPaths;p<np;++p) {
if ((_paths[p].address() == remoteAddr)&&(_paths[p].tcp() == fromSock->tcp())) {
_paths[p].received(now);
havePath = true;
break;
}
}
if (!havePath) {
unsigned int np = _numPaths;
if (np >= ZT_PEER_MAX_PATHS)
clean(now);
np = _numPaths;
if (np < ZT_PEER_MAX_PATHS) {
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[np].init(remoteAddr,pt,false);
_paths[np].received(now);
_numPaths = ++np;
}
}
}
/* Announce multicast groups of interest to direct peers if they are
* considered authorized members of a given network. Also announce to
* supernodes and network controllers. The other place this is done
* is in rescanMulticastGroups() in Network, but that only sends something
* if a network's multicast groups change. */
if ((now - _lastAnnouncedTo) >= ((ZT_MULTICAST_LIKE_EXPIRE / 2) - 1000)) {
_lastAnnouncedTo = now;
bool isSupernode = RR->topology->isSupernode(_id.address());
Packet outp(_id.address(),RR->identity.address(),Packet::VERB_MULTICAST_LIKE);
std::vector< SharedPtr<Network> > networks(RR->nc->networks());
for(std::vector< SharedPtr<Network> >::iterator n(networks.begin());n!=networks.end();++n) {
if ( ((*n)->isAllowed(_id.address())) || (isSupernode) ) {
std::set<MulticastGroup> mgs((*n)->multicastGroups());
for(std::set<MulticastGroup>::iterator mg(mgs.begin());mg!=mgs.end();++mg) {
if ((outp.size() + 18) > ZT_UDP_DEFAULT_PAYLOAD_MTU) {
outp.armor(_key,true);
fromSock->send(remoteAddr,outp.data(),outp.size());
outp.reset(_id.address(),RR->identity.address(),Packet::VERB_MULTICAST_LIKE);
}
// network ID, MAC, ADI
outp.append((uint64_t)(*n)->id());
mg->mac().appendTo(outp);
outp.append((uint32_t)mg->adi());
}
}
}
if (outp.size() > ZT_PROTO_MIN_PACKET_LENGTH) {
outp.armor(_key,true);
fromSock->send(remoteAddr,outp.data(),outp.size());
}
}
}
if ((verb == Packet::VERB_FRAME)||(verb == Packet::VERB_EXT_FRAME))
_lastUnicastFrame = now;
else if ((verb == Packet::VERB_P5_MULTICAST_FRAME)||(verb == Packet::VERB_MULTICAST_FRAME))
_lastMulticastFrame = now;
}
Path::Type Peer::send(const RuntimeEnvironment *RR,const void *data,unsigned int len,uint64_t now)
{
/* For sending ordinary packets, paths are divided into two categories:
* "normal" and "TCP out." Normal includes UDP and incoming TCP. We want
* to treat outbound TCP differently since if we use it it may end up
* overriding UDP and UDP performs much better. We only want to initiate
* TCP if it looks like UDP isn't available. */
Path *bestNormalPath = (Path *)0;
Path *bestTcpOutPath = (Path *)0;
uint64_t bestNormalPathLastReceived = 0;
uint64_t bestTcpOutPathLastReceived = 0;
for(unsigned int p=0,np=_numPaths;p<np;++p) {
uint64_t lr = _paths[p].lastReceived();
if (_paths[p].type() == Path::PATH_TYPE_TCP_OUT) {
if (lr >= bestTcpOutPathLastReceived) {
bestTcpOutPathLastReceived = lr;
bestTcpOutPath = &(_paths[p]);
}
} else {
if (lr >= bestNormalPathLastReceived) {
bestNormalPathLastReceived = lr;
bestNormalPath = &(_paths[p]);
}
}
}
Path *bestPath = (Path *)0;
uint64_t normalPathAge = now - bestNormalPathLastReceived;
uint64_t tcpOutPathAge = now - bestTcpOutPathLastReceived;
if (normalPathAge < ZT_PEER_PATH_ACTIVITY_TIMEOUT) {
/* If we have a normal path that looks alive, only use TCP if it looks
* even more alive, if the UDP path is not a very recent acquisition,
* and if TCP tunneling is globally enabled. */
bestPath = ( (tcpOutPathAge < normalPathAge) && (normalPathAge > (ZT_PEER_DIRECT_PING_DELAY / 4)) && (RR->tcpTunnelingEnabled) ) ? bestTcpOutPath : bestNormalPath;
} else if ( (tcpOutPathAge < ZT_PEER_PATH_ACTIVITY_TIMEOUT) || ((RR->tcpTunnelingEnabled)&&(bestTcpOutPath)) ) {
/* Otherwise use a TCP path if we have an active one or if TCP
* fallback has been globally triggered and we know of one at all. */
bestPath = bestTcpOutPath;
} else if ( (bestNormalPath) && (bestNormalPath->fixed()) ) {
/* Finally, use a normal path if we have a "fixed" one as these are
* always considered basically alive. */
bestPath = bestNormalPath;
}
/* Old path choice logic -- would attempt to use inactive paths... deprecating and will probably kill.
Path *bestPath = (Path *)0;
if (bestTcpOutPath) { // we have a TCP out path
if (bestNormalPath) { // we have both paths, decide which to use
if (RR->tcpTunnelingEnabled) { // TCP tunneling is enabled, so use normal path only if it looks alive
if ((bestNormalPathLastReceived > RR->timeOfLastResynchronize)&&((now - bestNormalPathLastReceived) < ZT_PEER_PATH_ACTIVITY_TIMEOUT))
bestPath = bestNormalPath;
else bestPath = bestTcpOutPath;
} else { // TCP tunneling is disabled, use normal path
bestPath = bestNormalPath;
}
} else { // we only have a TCP_OUT path, so use it regardless
bestPath = bestTcpOutPath;
}
} else { // we only have a normal path (or none at all, that case is caught below)
bestPath = bestNormalPath;
}
*/
if (!bestPath)
return Path::PATH_TYPE_NULL;
RR->antiRec->logOutgoingZT(data,len);
if (RR->sm->send(bestPath->address(),bestPath->tcp(),bestPath->type() == Path::PATH_TYPE_TCP_OUT,data,len)) {
bestPath->sent(now);
return bestPath->type();
}
return Path::PATH_TYPE_NULL;
}
bool Peer::sendPing(const RuntimeEnvironment *RR,uint64_t now)
{
bool sent = false;
SharedPtr<Peer> self(this);
/* Ping (and thus open) outbound TCP connections if we have no other options
* or if the TCP tunneling master switch is enabled and pings have been
* unanswered for ZT_TCP_TUNNEL_FAILOVER_TIMEOUT ms over normal channels. */
uint64_t lastNormalPingSent = 0;
uint64_t lastNormalReceive = 0;
bool haveNormal = false;
for(unsigned int p=0,np=_numPaths;p<np;++p) {
if (_paths[p].type() != Path::PATH_TYPE_TCP_OUT) {
lastNormalPingSent = std::max(lastNormalPingSent,_paths[p].lastPing());
lastNormalReceive = std::max(lastNormalReceive,_paths[p].lastReceived());
haveNormal = true;
}
}
const bool useTcpOut = ( (!haveNormal) || ( (RR->tcpTunnelingEnabled) && (lastNormalPingSent > RR->timeOfLastResynchronize) && (lastNormalPingSent > lastNormalReceive) && ((lastNormalPingSent - lastNormalReceive) >= ZT_TCP_TUNNEL_FAILOVER_TIMEOUT) ) );
TRACE("PING %s (useTcpOut==%d)",_id.address().toString().c_str(),(int)useTcpOut);
for(unsigned int p=0,np=_numPaths;p<np;++p) {
if ((useTcpOut)||(_paths[p].type() != Path::PATH_TYPE_TCP_OUT)) {
_paths[p].pinged(now); // attempts to ping are logged whether they look successful or not
if (RR->sw->sendHELLO(self,_paths[p])) {
_paths[p].sent(now);
sent = true;
}
}
}
return sent;
}
void Peer::clean(uint64_t now)
{
unsigned int np = _numPaths;
unsigned int x = 0;
unsigned int y = 0;
while (x < np) {
if (_paths[x].active(now))
_paths[y++] = _paths[x];
++x;
}
_numPaths = y;
}
void Peer::addPath(const Path &newp)
{
unsigned int np = _numPaths;
for(unsigned int p=0;p<np;++p) {
if (_paths[p] == newp) {
_paths[p].setFixed(newp.fixed());
return;
}
}
if (np >= ZT_PEER_MAX_PATHS)
clean(Utils::now());
np = _numPaths;
if (np < ZT_PEER_MAX_PATHS) {
_paths[np] = newp;
_numPaths = ++np;
}
}
void Peer::clearPaths(bool fixedToo)
{
if (fixedToo) {
_numPaths = 0;
} else {
unsigned int np = _numPaths;
unsigned int x = 0;
unsigned int y = 0;
while (x < np) {
if (_paths[x].fixed())
_paths[y++] = _paths[x];
++x;
}
_numPaths = y;
}
}
void Peer::getBestActiveUdpPathAddresses(uint64_t now,InetAddress &v4,InetAddress &v6) const
{
uint64_t bestV4 = 0,bestV6 = 0;
for(unsigned int p=0,np=_numPaths;p<np;++p) {
if ((_paths[p].type() == Path::PATH_TYPE_UDP)&&(_paths[p].active(now))) {
uint64_t lr = _paths[p].lastReceived();
if (lr) {
if (_paths[p].address().isV4()) {
if (lr >= bestV4) {
bestV4 = lr;
v4 = _paths[p].address();
}
} else if (_paths[p].address().isV6()) {
if (lr >= bestV6) {
bestV6 = lr;
v6 = _paths[p].address();
}
}
}
}
}
}
} // namespace ZeroTier