ZeroTierOne/node/Switch.cpp

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/*
* ZeroTier One - Global Peer to Peer Ethernet
* Copyright (C) 2012-2013 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 <stdio.h>
#include <stdlib.h>
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#include <algorithm>
#include <utility>
#include <stdexcept>
#include "Constants.hpp"
#ifdef __WINDOWS__
#include <WinSock2.h>
#include <Windows.h>
#endif
#include "Switch.hpp"
#include "Node.hpp"
#include "EthernetTap.hpp"
#include "InetAddress.hpp"
#include "Topology.hpp"
#include "RuntimeEnvironment.hpp"
#include "Peer.hpp"
#include "NodeConfig.hpp"
#include "Demarc.hpp"
#include "Filter.hpp"
#include "../version.h"
namespace ZeroTier {
Switch::Switch(const RuntimeEnvironment *renv) :
_r(renv)
{
}
Switch::~Switch()
{
}
void Switch::onRemotePacket(Demarc::Port localPort,const InetAddress &fromAddr,const Buffer<4096> &data)
{
try {
if (data.size() > ZT_PROTO_MIN_FRAGMENT_LENGTH) {
if (data[ZT_PACKET_FRAGMENT_IDX_FRAGMENT_INDICATOR] == ZT_PACKET_FRAGMENT_INDICATOR)
_handleRemotePacketFragment(localPort,fromAddr,data);
else if (data.size() > ZT_PROTO_MIN_PACKET_LENGTH)
_handleRemotePacketHead(localPort,fromAddr,data);
}
} catch (std::exception &ex) {
TRACE("dropped packet from %s: unexpected exception: %s",fromAddr.toString().c_str(),ex.what());
} catch ( ... ) {
TRACE("dropped packet from %s: unexpected exception: (unknown)",fromAddr.toString().c_str());
}
}
void Switch::onLocalEthernet(const SharedPtr<Network> &network,const MAC &from,const MAC &to,unsigned int etherType,const Buffer<4096> &data)
{
if (from != network->tap().mac()) {
LOG("ignored tap: %s -> %s %s (bridging is not (yet?) supported)",from.toString().c_str(),to.toString().c_str(),Filter::etherTypeName(etherType));
return;
}
if (to == network->tap().mac()) {
LOG("%s: frame received from self, ignoring (bridge loop? OS bug?)",network->tap().deviceName().c_str());
return;
}
if (!network->permitsEtherType(etherType)) {
LOG("ignored tap: %s -> %s: ethernet type %s not allowed on network %.16llx",from.toString().c_str(),to.toString().c_str(),Filter::etherTypeName(etherType),(unsigned long long)network->id());
return;
}
if (to.isMulticast()) {
MulticastGroup mg(to,0);
if (to.isBroadcast()) {
// Cram IPv4 IP into ADI field to make IPv4 ARP broadcast channel specific and scalable
if ((etherType == ZT_ETHERTYPE_ARP)&&(data.size() == 28)&&(data[2] == 0x08)&&(data[3] == 0x00)&&(data[4] == 6)&&(data[5] == 4)&&(data[7] == 0x01))
mg = MulticastGroup::deriveMulticastGroupForAddressResolution(InetAddress(data.field(24,4),4,0));
}
uint64_t crc = Multicaster::computeMulticastDedupCrc(network->id(),from,mg,etherType,data.data(),data.size());
uint64_t now = Utils::now();
if (_r->multicaster->checkDuplicate(crc,now)) {
LOG("%s/%.16llx: multicast group %s: dropped %u bytes, duplicate multicast in too short a time frame",network->tap().deviceName().c_str(),(unsigned long long)network->id(),mg.toString().c_str(),(unsigned int)data.size());
return;
}
_r->multicaster->addToDedupHistory(crc,now);
if (!network->updateAndCheckMulticastBalance(_r->identity.address(),mg,data.size())) {
LOG("%s/%.16llx: multicast group %s: dropped %u bytes, out of budget",network->tap().deviceName().c_str(),(unsigned long long)network->id(),mg.toString().c_str(),(unsigned int)data.size());
return;
}
Multicaster::MulticastBloomFilter bloom;
SharedPtr<Peer> propPeers[ZT_MULTICAST_PROPAGATION_BREADTH];
unsigned int np = _r->multicaster->pickSocialPropagationPeers(
*(_r->prng),
*(_r->topology),
network->id(),
mg,
_r->identity.address(),
Address(),
bloom,
ZT_MULTICAST_PROPAGATION_BREADTH,
propPeers,
now);
if (!np)
return;
C25519::Signature signature(Multicaster::signMulticastPacket(_r->identity,network->id(),from,mg,etherType,data.data(),data.size()));
Packet outpTmpl(propPeers[0]->address(),_r->identity.address(),Packet::VERB_MULTICAST_FRAME);
outpTmpl.append((uint8_t)0);
outpTmpl.append((uint64_t)network->id());
_r->identity.address().appendTo(outpTmpl);
outpTmpl.append(from.data,6);
outpTmpl.append(mg.mac().data,6);
outpTmpl.append((uint32_t)mg.adi());
outpTmpl.append(bloom.data(),ZT_PROTO_VERB_MULTICAST_FRAME_BLOOM_FILTER_SIZE_BYTES);
outpTmpl.append((uint8_t)0); // 0 hops
outpTmpl.append((uint16_t)etherType);
outpTmpl.append((uint16_t)data.size());
outpTmpl.append((uint16_t)signature.size());
outpTmpl.append(data.data(),data.size());
outpTmpl.append(signature.data,(unsigned int)signature.size());
outpTmpl.compress();
send(outpTmpl,true);
for(unsigned int i=1;i<np;++i) {
outpTmpl.newInitializationVector();
outpTmpl.setDestination(propPeers[i]->address());
send(outpTmpl,true);
}
} else if (to.isZeroTier()) {
// Simple unicast frame from us to another node
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Address toZT(to.data + 1,ZT_ADDRESS_LENGTH);
if (network->isAllowed(toZT)) {
Packet outp(toZT,_r->identity.address(),Packet::VERB_FRAME);
outp.append(network->id());
outp.append((uint16_t)etherType);
outp.append(data);
outp.compress();
send(outp,true);
} else {
TRACE("UNICAST: %s -> %s %s (dropped, destination not a member of closed network %llu)",from.toString().c_str(),to.toString().c_str(),Filter::etherTypeName(etherType),network->id());
}
} else {
TRACE("UNICAST: %s -> %s %s (dropped, destination MAC not ZeroTier)",from.toString().c_str(),to.toString().c_str(),Filter::etherTypeName(etherType));
}
}
void Switch::send(const Packet &packet,bool encrypt)
{
if (packet.destination() == _r->identity.address()) {
TRACE("BUG: caught attempt to send() to self, ignored");
return;
}
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//TRACE(">> %.16llx %s -> %s (size: %u) (enc: %s)",(unsigned long long)packet.packetId(),packet.source().toString().c_str(),packet.destination().toString().c_str(),packet.size(),(encrypt ? "yes" : "no"));
if (!_trySend(packet,encrypt)) {
Mutex::Lock _l(_txQueue_m);
_txQueue.insert(std::pair< Address,TXQueueEntry >(packet.destination(),TXQueueEntry(Utils::now(),packet,encrypt)));
}
}
void Switch::sendHELLO(const Address &dest)
{
Packet outp(dest,_r->identity.address(),Packet::VERB_HELLO);
outp.append((unsigned char)ZT_PROTO_VERSION);
outp.append((unsigned char)ZEROTIER_ONE_VERSION_MAJOR);
outp.append((unsigned char)ZEROTIER_ONE_VERSION_MINOR);
outp.append((uint16_t)ZEROTIER_ONE_VERSION_REVISION);
outp.append(Utils::now());
_r->identity.serialize(outp,false);
send(outp,false);
}
bool Switch::sendHELLO(const SharedPtr<Peer> &dest,Demarc::Port localPort,const InetAddress &remoteAddr)
{
uint64_t now = Utils::now();
Packet outp(dest->address(),_r->identity.address(),Packet::VERB_HELLO);
outp.append((unsigned char)ZT_PROTO_VERSION);
outp.append((unsigned char)ZEROTIER_ONE_VERSION_MAJOR);
outp.append((unsigned char)ZEROTIER_ONE_VERSION_MINOR);
outp.append((uint16_t)ZEROTIER_ONE_VERSION_REVISION);
outp.append(now);
_r->identity.serialize(outp,false);
outp.macSet(dest->macKey());
if (_r->demarc->send(localPort,remoteAddr,outp.data(),outp.size(),-1)) {
dest->onSent(_r,false,Packet::VERB_HELLO,now);
return true;
}
return false;
}
bool Switch::unite(const Address &p1,const Address &p2,bool force)
{
if ((p1 == _r->identity.address())||(p2 == _r->identity.address()))
return false;
SharedPtr<Peer> p1p = _r->topology->getPeer(p1);
if (!p1p)
return false;
SharedPtr<Peer> p2p = _r->topology->getPeer(p2);
if (!p2p)
return false;
uint64_t now = Utils::now();
std::pair<InetAddress,InetAddress> cg(Peer::findCommonGround(*p1p,*p2p,now));
if (!(cg.first))
return false;
// Addresses are sorted in key for last unite attempt map for order
// invariant lookup: (p1,p2) == (p2,p1)
Array<Address,2> uniteKey;
if (p1 >= p2) {
uniteKey[0] = p2;
uniteKey[1] = p1;
} else {
uniteKey[0] = p1;
uniteKey[1] = p2;
}
{
Mutex::Lock _l(_lastUniteAttempt_m);
std::map< Array< Address,2 >,uint64_t >::const_iterator e(_lastUniteAttempt.find(uniteKey));
if ((!force)&&(e != _lastUniteAttempt.end())&&((now - e->second) < ZT_MIN_UNITE_INTERVAL))
return false;
else _lastUniteAttempt[uniteKey] = now;
}
TRACE("unite: %s(%s) <> %s(%s)",p1.toString().c_str(),cg.second.toString().c_str(),p2.toString().c_str(),cg.first.toString().c_str());
{ // tell p1 where to find p2
Packet outp(p1,_r->identity.address(),Packet::VERB_RENDEZVOUS);
p2.appendTo(outp);
outp.append((uint16_t)cg.first.port());
if (cg.first.isV6()) {
outp.append((unsigned char)16);
outp.append(cg.first.rawIpData(),16);
} else {
outp.append((unsigned char)4);
outp.append(cg.first.rawIpData(),4);
}
outp.encrypt(p1p->cryptKey());
outp.macSet(p1p->macKey());
if (p1p->send(_r,outp.data(),outp.size(),now))
p1p->onSent(_r,false,Packet::VERB_RENDEZVOUS,now);
}
{ // tell p2 where to find p1
Packet outp(p2,_r->identity.address(),Packet::VERB_RENDEZVOUS);
p1.appendTo(outp);
outp.append((uint16_t)cg.second.port());
if (cg.second.isV6()) {
outp.append((unsigned char)16);
outp.append(cg.second.rawIpData(),16);
} else {
outp.append((unsigned char)4);
outp.append(cg.second.rawIpData(),4);
}
outp.encrypt(p2p->cryptKey());
outp.macSet(p2p->macKey());
if (p2p->send(_r,outp.data(),outp.size(),now))
p2p->onSent(_r,false,Packet::VERB_RENDEZVOUS,now);
}
return true;
}
void Switch::contact(const SharedPtr<Peer> &peer,const InetAddress &atAddr)
{
Demarc::Port fromPort = _r->demarc->pick(atAddr);
_r->demarc->send(fromPort,atAddr,"\0",1,ZT_FIREWALL_OPENER_HOPS);
{
Mutex::Lock _l(_contactQueue_m);
_contactQueue.push_back(ContactQueueEntry(peer,Utils::now() + ZT_RENDEZVOUS_NAT_T_DELAY,fromPort,atAddr));
}
// Kick main loop out of wait so that it can pick up this
// change to our scheduled timer tasks.
_r->mainLoopWaitCondition.signal();
}
unsigned long Switch::doTimerTasks()
{
unsigned long nextDelay = ~((unsigned long)0); // big number, caller will cap return value
uint64_t now = Utils::now();
{
Mutex::Lock _l(_contactQueue_m);
for(std::list<ContactQueueEntry>::iterator qi(_contactQueue.begin());qi!=_contactQueue.end();) {
if (now >= qi->fireAtTime) {
TRACE("sending NAT-T HELLO to %s(%s)",qi->peer->address().toString().c_str(),qi->inaddr.toString().c_str());
sendHELLO(qi->peer,qi->localPort,qi->inaddr);
_contactQueue.erase(qi++);
} else {
nextDelay = std::min(nextDelay,(unsigned long)(qi->fireAtTime - now));
++qi;
}
}
}
{
Mutex::Lock _l(_outstandingWhoisRequests_m);
for(std::map< Address,WhoisRequest >::iterator i(_outstandingWhoisRequests.begin());i!=_outstandingWhoisRequests.end();) {
unsigned long since = (unsigned long)(now - i->second.lastSent);
if (since >= ZT_WHOIS_RETRY_DELAY) {
if (i->second.retries >= ZT_MAX_WHOIS_RETRIES) {
TRACE("WHOIS %s timed out",i->first.toString().c_str());
_outstandingWhoisRequests.erase(i++);
continue;
} else {
i->second.lastSent = now;
i->second.peersConsulted[i->second.retries] = _sendWhoisRequest(i->first,i->second.peersConsulted,i->second.retries);
++i->second.retries;
TRACE("WHOIS %s (retry %u)",i->first.toString().c_str(),i->second.retries);
nextDelay = std::min(nextDelay,(unsigned long)ZT_WHOIS_RETRY_DELAY);
}
} else nextDelay = std::min(nextDelay,ZT_WHOIS_RETRY_DELAY - since);
++i;
}
}
{
Mutex::Lock _l(_txQueue_m);
for(std::multimap< Address,TXQueueEntry >::iterator i(_txQueue.begin());i!=_txQueue.end();) {
if (_trySend(i->second.packet,i->second.encrypt))
_txQueue.erase(i++);
else if ((now - i->second.creationTime) > ZT_TRANSMIT_QUEUE_TIMEOUT) {
TRACE("TX %s -> %s timed out",i->second.packet.source().toString().c_str(),i->second.packet.destination().toString().c_str());
_txQueue.erase(i++);
} else ++i;
}
}
{
Mutex::Lock _l(_rxQueue_m);
for(std::list< SharedPtr<PacketDecoder> >::iterator i(_rxQueue.begin());i!=_rxQueue.end();) {
if ((now - (*i)->receiveTime()) > ZT_RECEIVE_QUEUE_TIMEOUT) {
TRACE("RX %s -> %s timed out",(*i)->source().toString().c_str(),(*i)->destination().toString().c_str());
_rxQueue.erase(i++);
} else ++i;
}
}
{
Mutex::Lock _l(_defragQueue_m);
for(std::map< uint64_t,DefragQueueEntry >::iterator i(_defragQueue.begin());i!=_defragQueue.end();) {
if ((now - i->second.creationTime) > ZT_FRAGMENTED_PACKET_RECEIVE_TIMEOUT) {
TRACE("incomplete fragmented packet %.16llx timed out, fragments discarded",i->first);
_defragQueue.erase(i++);
} else ++i;
}
}
return std::max(nextDelay,(unsigned long)10); // minimum delay
}
void Switch::announceMulticastGroups(const std::map< SharedPtr<Network>,std::set<MulticastGroup> > &allMemberships)
{
std::vector< SharedPtr<Peer> > directPeers;
_r->topology->eachPeer(Topology::CollectPeersWithActiveDirectPath(directPeers));
#ifdef ZT_TRACE
unsigned int totalMulticastGroups = 0;
for(std::map< SharedPtr<Network>,std::set<MulticastGroup> >::const_iterator i(allMemberships.begin());i!=allMemberships.end();++i)
totalMulticastGroups += (unsigned int)i->second.size();
TRACE("announcing %u multicast groups for %u networks to %u peers",totalMulticastGroups,(unsigned int)allMemberships.size(),(unsigned int)directPeers.size());
#endif
for(std::vector< SharedPtr<Peer> >::iterator p(directPeers.begin());p!=directPeers.end();++p) {
Packet outp((*p)->address(),_r->identity.address(),Packet::VERB_MULTICAST_LIKE);
for(std::map< SharedPtr<Network>,std::set<MulticastGroup> >::const_iterator nwmgs(allMemberships.begin());nwmgs!=allMemberships.end();++nwmgs) {
if ((_r->topology->isSupernode((*p)->address()))||(nwmgs->first->isAllowed((*p)->address()))) {
for(std::set<MulticastGroup>::iterator mg(nwmgs->second.begin());mg!=nwmgs->second.end();++mg) {
if ((outp.size() + 18) > ZT_UDP_DEFAULT_PAYLOAD_MTU) {
send(outp,true);
outp.reset((*p)->address(),_r->identity.address(),Packet::VERB_MULTICAST_LIKE);
}
outp.append((uint64_t)nwmgs->first->id());
outp.append(mg->mac().data,6);
outp.append((uint32_t)mg->adi());
}
}
}
if (outp.size() > ZT_PROTO_MIN_PACKET_LENGTH)
send(outp,true);
}
}
void Switch::requestWhois(const Address &addr)
{
TRACE("requesting WHOIS for %s",addr.toString().c_str());
{
Mutex::Lock _l(_outstandingWhoisRequests_m);
std::pair< std::map< Address,WhoisRequest >::iterator,bool > entry(_outstandingWhoisRequests.insert(std::pair<Address,WhoisRequest>(addr,WhoisRequest())));
entry.first->second.lastSent = Utils::now();
entry.first->second.retries = 0; // reset retry count if entry already existed
}
_sendWhoisRequest(addr,(const Address *)0,0);
}
void Switch::doAnythingWaitingForPeer(const SharedPtr<Peer> &peer)
{
{
Mutex::Lock _l(_outstandingWhoisRequests_m);
_outstandingWhoisRequests.erase(peer->address());
}
{
Mutex::Lock _l(_rxQueue_m);
for(std::list< SharedPtr<PacketDecoder> >::iterator rxi(_rxQueue.begin());rxi!=_rxQueue.end();) {
if ((*rxi)->tryDecode(_r))
_rxQueue.erase(rxi++);
else ++rxi;
}
}
{
Mutex::Lock _l(_txQueue_m);
std::pair< std::multimap< Address,TXQueueEntry >::iterator,std::multimap< Address,TXQueueEntry >::iterator > waitingTxQueueItems(_txQueue.equal_range(peer->address()));
for(std::multimap< Address,TXQueueEntry >::iterator txi(waitingTxQueueItems.first);txi!=waitingTxQueueItems.second;) {
if (_trySend(txi->second.packet,txi->second.encrypt))
_txQueue.erase(txi++);
else ++txi;
}
}
}
void Switch::_handleRemotePacketFragment(Demarc::Port localPort,const InetAddress &fromAddr,const Buffer<4096> &data)
{
Packet::Fragment fragment(data);
Address destination(fragment.destination());
if (destination != _r->identity.address()) {
// Fragment is not for us, so try to relay it
if (fragment.hops() < ZT_RELAY_MAX_HOPS) {
fragment.incrementHops();
SharedPtr<Peer> relayTo = _r->topology->getPeer(destination);
if ((!relayTo)||(!relayTo->send(_r,fragment.data(),fragment.size(),Utils::now()))) {
relayTo = _r->topology->getBestSupernode();
if (relayTo)
relayTo->send(_r,fragment.data(),fragment.size(),Utils::now());
}
} else {
TRACE("dropped relay [fragment](%s) -> %s, max hops exceeded",fromAddr.toString().c_str(),destination.toString().c_str());
}
} else {
// Fragment looks like ours
uint64_t pid = fragment.packetId();
unsigned int fno = fragment.fragmentNumber();
unsigned int tf = fragment.totalFragments();
if ((tf <= ZT_MAX_PACKET_FRAGMENTS)&&(fno < ZT_MAX_PACKET_FRAGMENTS)&&(fno > 0)&&(tf > 1)) {
// Fragment appears basically sane. Its fragment number must be
// 1 or more, since a Packet with fragmented bit set is fragment 0.
// Total fragments must be more than 1, otherwise why are we
// seeing a Packet::Fragment?
Mutex::Lock _l(_defragQueue_m);
std::map< uint64_t,DefragQueueEntry >::iterator dqe(_defragQueue.find(pid));
if (dqe == _defragQueue.end()) {
// We received a Packet::Fragment without its head, so queue it and wait
DefragQueueEntry &dq = _defragQueue[pid];
dq.creationTime = Utils::now();
dq.frags[fno - 1] = fragment;
dq.totalFragments = tf; // total fragment count is known
dq.haveFragments = 1 << fno; // we have only this fragment
//TRACE("fragment (%u/%u) of %.16llx from %s",fno + 1,tf,pid,fromAddr.toString().c_str());
} else if (!(dqe->second.haveFragments & (1 << fno))) {
// We have other fragments and maybe the head, so add this one and check
dqe->second.frags[fno - 1] = fragment;
dqe->second.totalFragments = tf;
//TRACE("fragment (%u/%u) of %.16llx from %s",fno + 1,tf,pid,fromAddr.toString().c_str());
if (Utils::countBits(dqe->second.haveFragments |= (1 << fno)) == tf) {
// We have all fragments -- assemble and process full Packet
//TRACE("packet %.16llx is complete, assembling and processing...",pid);
SharedPtr<PacketDecoder> packet(dqe->second.frag0);
for(unsigned int f=1;f<tf;++f)
packet->append(dqe->second.frags[f - 1].payload(),dqe->second.frags[f - 1].payloadLength());
_defragQueue.erase(dqe);
if (!packet->tryDecode(_r)) {
Mutex::Lock _l(_rxQueue_m);
_rxQueue.push_back(packet);
}
}
} // else this is a duplicate fragment, ignore
}
}
}
void Switch::_handleRemotePacketHead(Demarc::Port localPort,const InetAddress &fromAddr,const Buffer<4096> &data)
{
SharedPtr<PacketDecoder> packet(new PacketDecoder(data,localPort,fromAddr));
Address source(packet->source());
Address destination(packet->destination());
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//TRACE("<< %.16llx %s -> %s (size: %u)",(unsigned long long)packet->packetId(),source.toString().c_str(),destination.toString().c_str(),packet->size());
if (destination != _r->identity.address()) {
// Packet is not for us, so try to relay it
if (packet->hops() < ZT_RELAY_MAX_HOPS) {
packet->incrementHops();
SharedPtr<Peer> relayTo = _r->topology->getPeer(destination);
if ((relayTo)&&(relayTo->send(_r,packet->data(),packet->size(),Utils::now()))) {
// If we've relayed, this periodically tries to get them to
// talk directly to save our bandwidth.
unite(source,destination,false);
} else {
// If we've received a packet not for us and we don't have
// a direct path to its recipient, pass it to (another)
// supernode. This can happen due to Internet weather -- the
// most direct supernode may not be reachable, yet another
// further away may be.
relayTo = _r->topology->getBestSupernode(&source,1,true);
if (relayTo)
relayTo->send(_r,packet->data(),packet->size(),Utils::now());
}
} else {
TRACE("dropped relay %s(%s) -> %s, max hops exceeded",packet->source().toString().c_str(),fromAddr.toString().c_str(),destination.toString().c_str());
}
} else if (packet->fragmented()) {
// Packet is the head of a fragmented packet series
uint64_t pid = packet->packetId();
Mutex::Lock _l(_defragQueue_m);
std::map< uint64_t,DefragQueueEntry >::iterator dqe(_defragQueue.find(pid));
if (dqe == _defragQueue.end()) {
// If we have no other fragments yet, create an entry and save the head
DefragQueueEntry &dq = _defragQueue[pid];
dq.creationTime = Utils::now();
dq.frag0 = packet;
dq.totalFragments = 0; // 0 == unknown, waiting for Packet::Fragment
dq.haveFragments = 1; // head is first bit (left to right)
//TRACE("fragment (0/?) of %.16llx from %s",pid,fromAddr.toString().c_str());
} else if (!(dqe->second.haveFragments & 1)) {
// If we have other fragments but no head, see if we are complete with the head
if ((dqe->second.totalFragments)&&(Utils::countBits(dqe->second.haveFragments |= 1) == dqe->second.totalFragments)) {
// We have all fragments -- assemble and process full Packet
//TRACE("packet %.16llx is complete, assembling and processing...",pid);
// packet already contains head, so append fragments
for(unsigned int f=1;f<dqe->second.totalFragments;++f)
packet->append(dqe->second.frags[f - 1].payload(),dqe->second.frags[f - 1].payloadLength());
_defragQueue.erase(dqe);
if (!packet->tryDecode(_r)) {
Mutex::Lock _l(_rxQueue_m);
_rxQueue.push_back(packet);
}
} else {
// Still waiting on more fragments, so queue the head
dqe->second.frag0 = packet;
}
} // else this is a duplicate head, ignore
} else {
// Packet is unfragmented, so just process it
if (!packet->tryDecode(_r)) {
Mutex::Lock _l(_rxQueue_m);
_rxQueue.push_back(packet);
}
}
}
Address Switch::_sendWhoisRequest(const Address &addr,const Address *peersAlreadyConsulted,unsigned int numPeersAlreadyConsulted)
{
SharedPtr<Peer> supernode(_r->topology->getBestSupernode(peersAlreadyConsulted,numPeersAlreadyConsulted,false));
if (supernode) {
Packet outp(supernode->address(),_r->identity.address(),Packet::VERB_WHOIS);
addr.appendTo(outp);
outp.encrypt(supernode->cryptKey());
outp.macSet(supernode->macKey());
uint64_t now = Utils::now();
if (supernode->send(_r,outp.data(),outp.size(),now)) {
supernode->onSent(_r,false,Packet::VERB_WHOIS,now);
return supernode->address();
}
}
return Address();
}
bool Switch::_trySend(const Packet &packet,bool encrypt)
{
SharedPtr<Peer> peer(_r->topology->getPeer(packet.destination()));
if (peer) {
uint64_t now = Utils::now();
bool isRelay;
SharedPtr<Peer> via;
if ((_r->topology->isSupernode(peer->address()))||(peer->hasActiveDirectPath(now))) {
isRelay = false;
via = peer;
} else {
isRelay = true;
via = _r->topology->getBestSupernode();
if (!via)
return false;
}
Packet tmp(packet);
unsigned int chunkSize = std::min(tmp.size(),(unsigned int)ZT_UDP_DEFAULT_PAYLOAD_MTU);
tmp.setFragmented(chunkSize < tmp.size());
if (encrypt)
tmp.encrypt(peer->cryptKey());
tmp.macSet(peer->macKey());
if (via->send(_r,tmp.data(),chunkSize,now)) {
if (chunkSize < tmp.size()) {
// Too big for one bite, fragment the rest
unsigned int fragStart = chunkSize;
unsigned int remaining = tmp.size() - chunkSize;
unsigned int fragsRemaining = (remaining / (ZT_UDP_DEFAULT_PAYLOAD_MTU - ZT_PROTO_MIN_FRAGMENT_LENGTH));
if ((fragsRemaining * (ZT_UDP_DEFAULT_PAYLOAD_MTU - ZT_PROTO_MIN_FRAGMENT_LENGTH)) < remaining)
++fragsRemaining;
unsigned int totalFragments = fragsRemaining + 1;
for(unsigned int f=0;f<fragsRemaining;++f) {
chunkSize = std::min(remaining,(unsigned int)(ZT_UDP_DEFAULT_PAYLOAD_MTU - ZT_PROTO_MIN_FRAGMENT_LENGTH));
Packet::Fragment frag(tmp,fragStart,chunkSize,f + 1,totalFragments);
if (!via->send(_r,frag.data(),frag.size(),now)) {
TRACE("WARNING: packet send to %s failed on later fragment #%u (check IP layer buffer sizes?)",via->address().toString().c_str(),f + 1);
}
fragStart += chunkSize;
remaining -= chunkSize;
}
}
via->onSent(_r,isRelay,packet.verb(),now);
return true;
}
return false;
}
requestWhois(packet.destination());
return false;
}
} // namespace ZeroTier