ZeroTierOne/node/Peer.cpp

1129 lines
36 KiB
C++

/*
* ZeroTier One - Network Virtualization Everywhere
* Copyright (C) 2011-2019 ZeroTier, Inc. https://www.zerotier.com/
*
* 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/>.
*
* --
*
* You can be released from the requirements of the license by purchasing
* a commercial license. Buying such a license is mandatory as soon as you
* develop commercial closed-source software that incorporates or links
* directly against ZeroTier software without disclosing the source code
* of your own application.
*/
#include "../version.h"
#include "Constants.hpp"
#include "Peer.hpp"
#include "Node.hpp"
#include "Switch.hpp"
#include "Network.hpp"
#include "SelfAwareness.hpp"
#include "Packet.hpp"
#include "Trace.hpp"
#include "InetAddress.hpp"
#include "RingBuffer.hpp"
#include "Utils.hpp"
#include "../include/ZeroTierDebug.h"
namespace ZeroTier {
static unsigned char s_freeRandomByteCounter = 0;
Peer::Peer(const RuntimeEnvironment *renv,const Identity &myIdentity,const Identity &peerIdentity) :
RR(renv),
_lastReceive(0),
_lastNontrivialReceive(0),
_lastTriedMemorizedPath(0),
_lastDirectPathPushSent(0),
_lastDirectPathPushReceive(0),
_lastCredentialRequestSent(0),
_lastWhoisRequestReceived(0),
_lastEchoRequestReceived(0),
_lastCredentialsReceived(0),
_lastTrustEstablishedPacketReceived(0),
_lastSentFullHello(0),
_lastACKWindowReset(0),
_lastQoSWindowReset(0),
_lastMultipathCompatibilityCheck(0),
_freeRandomByte((unsigned char)((uintptr_t)this >> 4) ^ ++s_freeRandomByteCounter),
_uniqueAlivePathCount(0),
_localMultipathSupported(false),
_remoteMultipathSupported(false),
_canUseMultipath(false),
_vProto(0),
_vMajor(0),
_vMinor(0),
_vRevision(0),
_id(peerIdentity),
_directPathPushCutoffCount(0),
_credentialsCutoffCount(0),
_linkIsBalanced(false),
_linkIsRedundant(false),
_remotePeerMultipathEnabled(false),
_lastAggregateStatsReport(0),
_lastAggregateAllocation(0),
_virtualPathCount(0),
_roundRobinPathAssignmentIdx(0),
_pathAssignmentIdx(0)
{
if (!myIdentity.agree(peerIdentity,_key,ZT_PEER_SECRET_KEY_LENGTH))
throw ZT_EXCEPTION_INVALID_ARGUMENT;
}
void Peer::received(
void *tPtr,
const SharedPtr<Path> &path,
const unsigned int hops,
const uint64_t packetId,
const unsigned int payloadLength,
const Packet::Verb verb,
const uint64_t inRePacketId,
const Packet::Verb inReVerb,
const bool trustEstablished,
const uint64_t networkId)
{
const int64_t now = RR->node->now();
_lastReceive = now;
switch (verb) {
case Packet::VERB_FRAME:
case Packet::VERB_EXT_FRAME:
case Packet::VERB_NETWORK_CONFIG_REQUEST:
case Packet::VERB_NETWORK_CONFIG:
case Packet::VERB_MULTICAST_FRAME:
_lastNontrivialReceive = now;
break;
default:
break;
}
if (trustEstablished) {
_lastTrustEstablishedPacketReceived = now;
path->trustedPacketReceived(now);
}
{
Mutex::Lock _l(_paths_m);
recordIncomingPacket(tPtr, path, packetId, payloadLength, verb, now);
if (_canUseMultipath) {
if (path->needsToSendQoS(now)) {
sendQOS_MEASUREMENT(tPtr, path, path->localSocket(), path->address(), now);
}
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
_paths[i].p->processBackgroundPathMeasurements(now);
}
}
}
}
if (hops == 0) {
// If this is a direct packet (no hops), update existing paths or learn new ones
bool havePath = false;
{
Mutex::Lock _l(_paths_m);
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
if (_paths[i].p == path) {
_paths[i].lr = now;
havePath = true;
break;
}
} else break;
}
}
bool attemptToContact = false;
if ((!havePath)&&(RR->node->shouldUsePathForZeroTierTraffic(tPtr,_id.address(),path->localSocket(),path->address()))) {
Mutex::Lock _l(_paths_m);
// Paths are redundant if they duplicate an alive path to the same IP or
// with the same local socket and address family.
bool redundant = false;
unsigned int replacePath = ZT_MAX_PEER_NETWORK_PATHS;
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
if ( (_paths[i].p->alive(now)) && ( ((_paths[i].p->localSocket() == path->localSocket())&&(_paths[i].p->address().ss_family == path->address().ss_family)) || (_paths[i].p->address().ipsEqual2(path->address())) ) ) {
redundant = true;
break;
}
// If the path is the same address and port, simply assume this is a replacement
if ( (_paths[i].p->address().ipsEqual2(path->address()))) {
replacePath = i;
break;
}
} else break;
}
// If the path isn't a duplicate of the same localSocket AND we haven't already determined a replacePath,
// then find the worst path and replace it.
if (!redundant && replacePath == ZT_MAX_PEER_NETWORK_PATHS) {
int replacePathQuality = 0;
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
const int q = _paths[i].p->quality(now);
if (q > replacePathQuality) {
replacePathQuality = q;
replacePath = i;
}
} else {
replacePath = i;
break;
}
}
}
if (replacePath != ZT_MAX_PEER_NETWORK_PATHS) {
if (verb == Packet::VERB_OK) {
RR->t->peerLearnedNewPath(tPtr,networkId,*this,path,packetId);
_paths[replacePath].lr = now;
_paths[replacePath].p = path;
_paths[replacePath].priority = 1;
} else {
attemptToContact = true;
}
// Every time we learn of new path, rebuild set of virtual paths
constructSetOfVirtualPaths();
}
}
if (attemptToContact) {
attemptToContactAt(tPtr,path->localSocket(),path->address(),now,true);
path->sent(now);
RR->t->peerConfirmingUnknownPath(tPtr,networkId,*this,path,packetId,verb);
}
}
// If we have a trust relationship periodically push a message enumerating
// all known external addresses for ourselves. If we already have a path this
// is done less frequently.
if (this->trustEstablished(now)) {
const int64_t sinceLastPush = now - _lastDirectPathPushSent;
if (sinceLastPush >= ((hops == 0) ? ZT_DIRECT_PATH_PUSH_INTERVAL_HAVEPATH : ZT_DIRECT_PATH_PUSH_INTERVAL)
|| (_localMultipathSupported && (sinceLastPush >= (ZT_DIRECT_PATH_PUSH_INTERVAL_MULTIPATH)))) {
_lastDirectPathPushSent = now;
std::vector<InetAddress> pathsToPush(RR->node->directPaths());
if (pathsToPush.size() > 0) {
std::vector<InetAddress>::const_iterator p(pathsToPush.begin());
while (p != pathsToPush.end()) {
Packet *const outp = new Packet(_id.address(),RR->identity.address(),Packet::VERB_PUSH_DIRECT_PATHS);
outp->addSize(2); // leave room for count
unsigned int count = 0;
while ((p != pathsToPush.end())&&((outp->size() + 24) < 1200)) {
uint8_t addressType = 4;
switch(p->ss_family) {
case AF_INET:
break;
case AF_INET6:
addressType = 6;
break;
default: // we currently only push IP addresses
++p;
continue;
}
outp->append((uint8_t)0); // no flags
outp->append((uint16_t)0); // no extensions
outp->append(addressType);
outp->append((uint8_t)((addressType == 4) ? 6 : 18));
outp->append(p->rawIpData(),((addressType == 4) ? 4 : 16));
outp->append((uint16_t)p->port());
++count;
++p;
}
if (count) {
outp->setAt(ZT_PACKET_IDX_PAYLOAD,(uint16_t)count);
outp->compress();
outp->armor(_key,true);
path->send(RR,tPtr,outp->data(),outp->size(),now);
}
delete outp;
}
}
}
}
}
void Peer::constructSetOfVirtualPaths()
{
if (!_remoteMultipathSupported) {
return;
}
Mutex::Lock _l(_virtual_paths_m);
int64_t now = RR->node->now();
_virtualPathCount = 0;
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p && _paths[i].p->alive(now)) {
for(unsigned int j=0;j<ZT_MAX_PEER_NETWORK_PATHS;++j) {
if (_paths[j].p && _paths[j].p->alive(now)) {
int64_t localSocket = _paths[j].p->localSocket();
bool foundVirtualPath = false;
for (int k=0; k<_virtualPaths.size(); k++) {
if (_virtualPaths[k]->localSocket == localSocket && _virtualPaths[k]->p == _paths[i].p) {
foundVirtualPath = true;
}
}
if (!foundVirtualPath)
{
VirtualPath *np = new VirtualPath;
np->p = _paths[i].p;
np->localSocket = localSocket;
_virtualPaths.push_back(np);
}
}
}
}
}
}
void Peer::recordOutgoingPacket(const SharedPtr<Path> &path, const uint64_t packetId,
uint16_t payloadLength, const Packet::Verb verb, int64_t now)
{
_freeRandomByte += (unsigned char)(packetId >> 8); // grab entropy to use in path selection logic for multipath
if (_canUseMultipath) {
path->recordOutgoingPacket(now, packetId, payloadLength, verb);
}
}
void Peer::recordIncomingPacket(void *tPtr, const SharedPtr<Path> &path, const uint64_t packetId,
uint16_t payloadLength, const Packet::Verb verb, int64_t now)
{
if (_canUseMultipath) {
if (path->needsToSendAck(now)) {
sendACK(tPtr, path, path->localSocket(), path->address(), now);
}
path->recordIncomingPacket(now, packetId, payloadLength, verb);
}
}
void Peer::computeAggregateAllocation(int64_t now)
{
float maxStability = 0;
float totalRelativeQuality = 0;
float maxThroughput = 1;
float maxScope = 0;
float relStability[ZT_MAX_PEER_NETWORK_PATHS];
float relThroughput[ZT_MAX_PEER_NETWORK_PATHS];
memset(&relStability, 0, sizeof(relStability));
memset(&relThroughput, 0, sizeof(relThroughput));
// Survey all paths
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
relStability[i] = _paths[i].p->lastComputedStability();
relThroughput[i] = (float)_paths[i].p->maxLifetimeThroughput();
maxStability = relStability[i] > maxStability ? relStability[i] : maxStability;
maxThroughput = relThroughput[i] > maxThroughput ? relThroughput[i] : maxThroughput;
maxScope = _paths[i].p->ipScope() > maxScope ? _paths[i].p->ipScope() : maxScope;
}
}
// Convert to relative values
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
relStability[i] /= maxStability ? maxStability : 1;
relThroughput[i] /= maxThroughput ? maxThroughput : 1;
float normalized_ma = Utils::normalize((float)_paths[i].p->ackAge(now), 0, ZT_PATH_MAX_AGE, 0, 10);
float age_contrib = exp((-1)*normalized_ma);
float relScope = ((float)(_paths[i].p->ipScope()+1) / (maxScope + 1));
float relQuality =
(relStability[i] * (float)ZT_PATH_CONTRIB_STABILITY)
+ (fmaxf(1.0f, relThroughput[i]) * (float)ZT_PATH_CONTRIB_THROUGHPUT)
+ relScope * (float)ZT_PATH_CONTRIB_SCOPE;
relQuality *= age_contrib;
// Clamp values
relQuality = relQuality > (1.00f / 100.0f) ? relQuality : 0.0f;
relQuality = relQuality < (99.0f / 100.0f) ? relQuality : 1.0f;
totalRelativeQuality += relQuality;
_paths[i].p->updateRelativeQuality(relQuality);
}
}
// Convert set of relative performances into an allocation set
for(uint16_t i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
if (RR->node->getMultipathMode() == ZT_MULTIPATH_BALANCE_RANDOM) {
_paths[i].p->updateComponentAllocationOfAggregateLink(((float)_pathChoiceHist.countValue(i) / (float)_pathChoiceHist.count()) * 255);
}
if (RR->node->getMultipathMode() == ZT_MULTIPATH_BALANCE_DYNAMIC_OPAQUE) {
_paths[i].p->updateComponentAllocationOfAggregateLink((unsigned char)((_paths[i].p->relativeQuality() / totalRelativeQuality) * 255));
}
}
}
}
int Peer::computeAggregateLinkPacketDelayVariance()
{
float pdv = 0.0;
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
pdv += _paths[i].p->relativeQuality() * _paths[i].p->packetDelayVariance();
}
}
return (int)pdv;
}
int Peer::computeAggregateLinkMeanLatency()
{
int ml = 0;
int pathCount = 0;
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
pathCount++;
ml += (int)(_paths[i].p->relativeQuality() * _paths[i].p->meanLatency());
}
}
return ml / pathCount;
}
int Peer::aggregateLinkPhysicalPathCount()
{
std::map<std::string, bool> ifnamemap;
int pathCount = 0;
int64_t now = RR->node->now();
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p && _paths[i].p->alive(now)) {
if (!ifnamemap[_paths[i].p->getName()]) {
ifnamemap[_paths[i].p->getName()] = true;
pathCount++;
}
}
}
return pathCount;
}
int Peer::aggregateLinkLogicalPathCount()
{
int pathCount = 0;
int64_t now = RR->node->now();
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p && _paths[i].p->alive(now)) {
pathCount++;
}
}
return pathCount;
}
std::vector<SharedPtr<Path> > Peer::getAllPaths(int64_t now)
{
Mutex::Lock _l(_virtual_paths_m); // FIXME: TX can now lock RX
std::vector<SharedPtr<Path> > paths;
for (int i=0; i<_virtualPaths.size(); i++) {
if (_virtualPaths[i]->p) {
paths.push_back(_virtualPaths[i]->p);
}
}
return paths;
}
SharedPtr<Path> Peer::getAppropriatePath(int64_t now, bool includeExpired, int64_t flowId)
{
Mutex::Lock _l(_paths_m);
SharedPtr<Path> selectedPath;
char curPathStr[128];
char newPathStr[128];
unsigned int bestPath = ZT_MAX_PEER_NETWORK_PATHS;
/**
* Send traffic across the highest quality path only. This algorithm will still
* use the old path quality metric from protocol version 9.
*/
if (!_canUseMultipath) {
long bestPathQuality = 2147483647;
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
if ((includeExpired)||((now - _paths[i].lr) < ZT_PEER_PATH_EXPIRATION)) {
const long q = _paths[i].p->quality(now) / _paths[i].priority;
if (q <= bestPathQuality) {
bestPathQuality = q;
bestPath = i;
}
}
} else break;
}
if (bestPath != ZT_MAX_PEER_NETWORK_PATHS) {
return _paths[bestPath].p;
}
return SharedPtr<Path>();
}
// Update path measurements
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
_paths[i].p->processBackgroundPathMeasurements(now);
}
}
if (RR->sw->isFlowAware()) {
// Detect new flows and update existing records
if (_flows.count(flowId)) {
_flows[flowId]->lastSend = now;
}
else {
fprintf(stderr, "new flow %llx detected between this node and %llx (%lu active flow(s))\n",
flowId, this->_id.address().toInt(), (_flows.size()+1));
struct Flow *newFlow = new Flow(flowId, now);
_flows[flowId] = newFlow;
newFlow->assignedPath = nullptr;
}
}
// Construct set of virtual paths if needed
if (!_virtualPaths.size()) {
constructSetOfVirtualPaths();
}
if (!_virtualPaths.size()) {
fprintf(stderr, "no paths to send packet out on\n");
return SharedPtr<Path>();
}
/**
* Traffic is randomly distributed among all active paths.
*/
int numAlivePaths = 0;
int numStalePaths = 0;
if (RR->node->getMultipathMode() == ZT_MULTIPATH_BALANCE_RANDOM) {
int sz = _virtualPaths.size();
if (sz) {
int idx = _freeRandomByte % sz;
_pathChoiceHist.push(idx);
char pathStr[128];
_virtualPaths[idx]->p->address().toString(pathStr);
fprintf(stderr, "sending out: (%llx), idx=%d: path=%s, localSocket=%lld\n",
this->_id.address().toInt(), idx, pathStr, _virtualPaths[idx]->localSocket);
return _virtualPaths[idx]->p;
}
// This call is algorithmically inert but gives us a value to show in the status output
computeAggregateAllocation(now);
}
/**
* All traffic is sent on all paths.
*/
if (RR->node->getMultipathMode() == ZT_MULTIPATH_BROADCAST) {
// Not handled here. Handled in Switch::_trySend()
}
/**
* Only one link is active. Fail-over is immediate.
*/
if (RR->node->getMultipathMode() == ZT_MULTIPATH_ACTIVE_BACKUP) {
bool bFoundHotPath = false;
if (!_activeBackupPath) {
/* Select the fist path that appears to still be active.
* This will eventually be user-configurable */
for (int i=0; i<ZT_MAX_PEER_NETWORK_PATHS; i++) {
if (_paths[i].p) {
if (_activeBackupPath.ptr() == _paths[i].p.ptr()) {
continue;
}
_activeBackupPath = _paths[i].p;
if ((now - _paths[i].p->lastIn()) < ZT_MULTIPATH_ACTIVE_BACKUP_RAPID_FAILOVER_PERIOD) {
bFoundHotPath = true;
_activeBackupPath = _paths[i].p;
_pathAssignmentIdx = i;
_activeBackupPath->address().toString(curPathStr);
fprintf(stderr, "selected %s as the primary active-backup path to %llx (idx=%d)\n",
curPathStr, this->_id.address().toInt(), _pathAssignmentIdx);
break;
}
}
}
}
else {
char what[128];
if ((now - _activeBackupPath->lastIn()) > ZT_MULTIPATH_ACTIVE_BACKUP_RAPID_FAILOVER_PERIOD) {
_activeBackupPath->address().toString(curPathStr); // Record path string for later debug trace
int16_t previousIdx = _pathAssignmentIdx;
SharedPtr<Path> nextAlternativePath;
// Search for a hot path, at the same time find the next path in
// a RR sequence that seems viable to use as an alternative
int searchCount = 0;
while (searchCount < ZT_MAX_PEER_NETWORK_PATHS) {
_pathAssignmentIdx++;
if (_pathAssignmentIdx == ZT_MAX_PEER_NETWORK_PATHS) {
_pathAssignmentIdx = 0;
}
searchCount++;
if (_paths[_pathAssignmentIdx].p) {
_paths[_pathAssignmentIdx].p->address().toString(what);
if (_activeBackupPath.ptr() == _paths[_pathAssignmentIdx].p.ptr()) {
continue;
}
if (!nextAlternativePath) { // Record the first viable alternative in the RR sequence
nextAlternativePath = _paths[_pathAssignmentIdx].p;
}
if ((now - _paths[_pathAssignmentIdx].p->lastIn()) < ZT_MULTIPATH_ACTIVE_BACKUP_RAPID_FAILOVER_PERIOD) {
bFoundHotPath = true;
_activeBackupPath = _paths[_pathAssignmentIdx].p;
_activeBackupPath->address().toString(newPathStr);
fprintf(stderr, "primary active-backup path %s to %llx appears to be dead, switched to %s\n",
curPathStr, this->_id.address().toInt(), newPathStr);
break;
}
}
}
if (!bFoundHotPath) {
if (nextAlternativePath) {
_activeBackupPath = nextAlternativePath;
_activeBackupPath->address().toString(curPathStr);
//fprintf(stderr, "no hot paths found to use as active-backup primary to %llx, using next best: %s\n",
// this->_id.address().toInt(), curPathStr);
}
else {
// No change
}
}
}
}
if (!_activeBackupPath) {
return SharedPtr<Path>();
}
return _activeBackupPath;
}
/**
* Packets are striped across all available paths.
*/
if (RR->node->getMultipathMode() == ZT_MULTIPATH_BALANCE_RR_OPAQUE) {
// fprintf(stderr, "ZT_MULTIPATH_BALANCE_RR_OPAQUE\n");
int16_t previousIdx = _roundRobinPathAssignmentIdx;
if (_roundRobinPathAssignmentIdx < (_virtualPaths.size()-1)) {
_roundRobinPathAssignmentIdx++;
}
else {
_roundRobinPathAssignmentIdx = 0;
}
selectedPath = _virtualPaths[previousIdx]->p;
char pathStr[128];
selectedPath->address().toString(pathStr);
fprintf(stderr, "sending packet out on path %s at index %d\n",
pathStr, previousIdx);
return selectedPath;
}
/**
* Flows are striped across all available paths.
*/
if (RR->node->getMultipathMode() == ZT_MULTIPATH_BALANCE_RR_FLOW) {
// fprintf(stderr, "ZT_MULTIPATH_BALANCE_RR_FLOW\n");
}
/**
* Flows are hashed across all available paths.
*/
if (RR->node->getMultipathMode() == ZT_MULTIPATH_BALANCE_XOR_FLOW) {
// fprintf(stderr, "ZT_MULTIPATH_BALANCE_XOR_FLOW (%llx) \n", flowId);
struct Flow *currFlow = NULL;
if (_flows.count(flowId)) {
currFlow = _flows[flowId];
if (!currFlow->assignedPath) {
int idx = abs((int)(currFlow->flowId % (_virtualPaths.size()-1)));
currFlow->assignedPath = _virtualPaths[idx];
_virtualPaths[idx]->p->address().toString(curPathStr);
fprintf(stderr, "assigning flow %llx between this node and peer %llx to path %s at index %d\n",
currFlow->flowId, this->_id.address().toInt(), curPathStr, idx);
}
else {
if (!currFlow->assignedPath->p->alive(now)) {
currFlow->assignedPath->p->address().toString(curPathStr);
// Re-assign
int idx = abs((int)(currFlow->flowId % (_virtualPaths.size()-1)));
currFlow->assignedPath = _virtualPaths[idx];
_virtualPaths[idx]->p->address().toString(newPathStr);
fprintf(stderr, "path %s assigned to flow %llx between this node and %llx appears to be dead, reassigning to path %s\n",
curPathStr, currFlow->flowId, this->_id.address().toInt(), newPathStr);
}
}
return currFlow->assignedPath->p;
}
}
/**
* Proportionally allocate traffic according to dynamic path quality measurements.
*/
if (RR->node->getMultipathMode() == ZT_MULTIPATH_BALANCE_DYNAMIC_OPAQUE) {
if ((now - _lastAggregateAllocation) >= ZT_PATH_QUALITY_COMPUTE_INTERVAL) {
_lastAggregateAllocation = now;
computeAggregateAllocation(now);
}
// Randomly choose path according to their allocations
float rf = _freeRandomByte;
for(int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
if (rf < _paths[i].p->allocation()) {
bestPath = i;
_pathChoiceHist.push(bestPath); // Record which path we chose
break;
}
rf -= _paths[i].p->allocation();
}
}
if (bestPath < ZT_MAX_PEER_NETWORK_PATHS) {
return _paths[bestPath].p;
}
}
/**
* Flows are dynamically allocated across paths in proportion to link strength and load.
*/
if (RR->node->getMultipathMode() == ZT_MULTIPATH_BALANCE_DYNAMIC_FLOW) {
}
return SharedPtr<Path>();
}
char *Peer::interfaceListStr()
{
std::map<std::string, int> ifnamemap;
char tmp[32];
const int64_t now = RR->node->now();
char *ptr = _interfaceListStr;
bool imbalanced = false;
memset(_interfaceListStr, 0, sizeof(_interfaceListStr));
int alivePathCount = aggregateLinkLogicalPathCount();
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p && _paths[i].p->alive(now)) {
int ipv = _paths[i].p->address().isV4();
// If this is acting as an aggregate link, check allocations
float targetAllocation = 1.0f / (float)alivePathCount;
float currentAllocation = 1.0f;
if (alivePathCount > 1) {
currentAllocation = (float)_pathChoiceHist.countValue(i) / (float)_pathChoiceHist.count();
if (fabs(targetAllocation - currentAllocation) > ZT_PATH_IMBALANCE_THRESHOLD) {
imbalanced = true;
}
}
char *ipvStr = ipv ? (char*)"ipv4" : (char*)"ipv6";
sprintf(tmp, "(%s, %s, %.3f)", _paths[i].p->getName(), ipvStr, currentAllocation);
// Prevent duplicates
if(ifnamemap[_paths[i].p->getName()] != ipv) {
memcpy(ptr, tmp, strlen(tmp));
ptr += strlen(tmp);
*ptr = ' ';
ptr++;
ifnamemap[_paths[i].p->getName()] = ipv;
}
}
}
ptr--; // Overwrite trailing space
if (imbalanced) {
sprintf(tmp, ", is asymmetrical");
memcpy(ptr, tmp, sizeof(tmp));
} else {
*ptr = '\0';
}
return _interfaceListStr;
}
void Peer::introduce(void *const tPtr,const int64_t now,const SharedPtr<Peer> &other) const
{
unsigned int myBestV4ByScope[ZT_INETADDRESS_MAX_SCOPE+1];
unsigned int myBestV6ByScope[ZT_INETADDRESS_MAX_SCOPE+1];
long myBestV4QualityByScope[ZT_INETADDRESS_MAX_SCOPE+1];
long myBestV6QualityByScope[ZT_INETADDRESS_MAX_SCOPE+1];
unsigned int theirBestV4ByScope[ZT_INETADDRESS_MAX_SCOPE+1];
unsigned int theirBestV6ByScope[ZT_INETADDRESS_MAX_SCOPE+1];
long theirBestV4QualityByScope[ZT_INETADDRESS_MAX_SCOPE+1];
long theirBestV6QualityByScope[ZT_INETADDRESS_MAX_SCOPE+1];
for(int i=0;i<=ZT_INETADDRESS_MAX_SCOPE;++i) {
myBestV4ByScope[i] = ZT_MAX_PEER_NETWORK_PATHS;
myBestV6ByScope[i] = ZT_MAX_PEER_NETWORK_PATHS;
myBestV4QualityByScope[i] = 2147483647;
myBestV6QualityByScope[i] = 2147483647;
theirBestV4ByScope[i] = ZT_MAX_PEER_NETWORK_PATHS;
theirBestV6ByScope[i] = ZT_MAX_PEER_NETWORK_PATHS;
theirBestV4QualityByScope[i] = 2147483647;
theirBestV6QualityByScope[i] = 2147483647;
}
Mutex::Lock _l1(_paths_m);
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
const long q = _paths[i].p->quality(now) / _paths[i].priority;
const unsigned int s = (unsigned int)_paths[i].p->ipScope();
switch(_paths[i].p->address().ss_family) {
case AF_INET:
if (q <= myBestV4QualityByScope[s]) {
myBestV4QualityByScope[s] = q;
myBestV4ByScope[s] = i;
}
break;
case AF_INET6:
if (q <= myBestV6QualityByScope[s]) {
myBestV6QualityByScope[s] = q;
myBestV6ByScope[s] = i;
}
break;
}
} else break;
}
Mutex::Lock _l2(other->_paths_m);
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (other->_paths[i].p) {
const long q = other->_paths[i].p->quality(now) / other->_paths[i].priority;
const unsigned int s = (unsigned int)other->_paths[i].p->ipScope();
switch(other->_paths[i].p->address().ss_family) {
case AF_INET:
if (q <= theirBestV4QualityByScope[s]) {
theirBestV4QualityByScope[s] = q;
theirBestV4ByScope[s] = i;
}
break;
case AF_INET6:
if (q <= theirBestV6QualityByScope[s]) {
theirBestV6QualityByScope[s] = q;
theirBestV6ByScope[s] = i;
}
break;
}
} else break;
}
unsigned int mine = ZT_MAX_PEER_NETWORK_PATHS;
unsigned int theirs = ZT_MAX_PEER_NETWORK_PATHS;
for(int s=ZT_INETADDRESS_MAX_SCOPE;s>=0;--s) {
if ((myBestV6ByScope[s] != ZT_MAX_PEER_NETWORK_PATHS)&&(theirBestV6ByScope[s] != ZT_MAX_PEER_NETWORK_PATHS)) {
mine = myBestV6ByScope[s];
theirs = theirBestV6ByScope[s];
break;
}
if ((myBestV4ByScope[s] != ZT_MAX_PEER_NETWORK_PATHS)&&(theirBestV4ByScope[s] != ZT_MAX_PEER_NETWORK_PATHS)) {
mine = myBestV4ByScope[s];
theirs = theirBestV4ByScope[s];
break;
}
}
if (mine != ZT_MAX_PEER_NETWORK_PATHS) {
unsigned int alt = (unsigned int)RR->node->prng() & 1; // randomize which hint we send first for black magickal NAT-t reasons
const unsigned int completed = alt + 2;
while (alt != completed) {
if ((alt & 1) == 0) {
Packet outp(_id.address(),RR->identity.address(),Packet::VERB_RENDEZVOUS);
outp.append((uint8_t)0);
other->_id.address().appendTo(outp);
outp.append((uint16_t)other->_paths[theirs].p->address().port());
if (other->_paths[theirs].p->address().ss_family == AF_INET6) {
outp.append((uint8_t)16);
outp.append(other->_paths[theirs].p->address().rawIpData(),16);
} else {
outp.append((uint8_t)4);
outp.append(other->_paths[theirs].p->address().rawIpData(),4);
}
outp.armor(_key,true);
_paths[mine].p->send(RR,tPtr,outp.data(),outp.size(),now);
} else {
Packet outp(other->_id.address(),RR->identity.address(),Packet::VERB_RENDEZVOUS);
outp.append((uint8_t)0);
_id.address().appendTo(outp);
outp.append((uint16_t)_paths[mine].p->address().port());
if (_paths[mine].p->address().ss_family == AF_INET6) {
outp.append((uint8_t)16);
outp.append(_paths[mine].p->address().rawIpData(),16);
} else {
outp.append((uint8_t)4);
outp.append(_paths[mine].p->address().rawIpData(),4);
}
outp.armor(other->_key,true);
other->_paths[theirs].p->send(RR,tPtr,outp.data(),outp.size(),now);
}
++alt;
}
}
}
inline void Peer::processBackgroundPeerTasks(const int64_t now)
{
// Determine current multipath compatibility with other peer
if ((now - _lastMultipathCompatibilityCheck) >= ZT_PATH_QUALITY_COMPUTE_INTERVAL) {
//
// Cache number of available paths so that we can short-circuit multipath logic elsewhere
//
// We also take notice of duplicate paths (same IP only) because we may have
// recently received a direct path push from a peer and our list might contain
// a dead path which hasn't been fully recognized as such. In this case we
// don't want the duplicate to trigger execution of multipath code prematurely.
//
// This is done to support the behavior of auto multipath enable/disable
// without user intervention.
//
int currAlivePathCount = 0;
int duplicatePathsFound = 0;
for (unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
currAlivePathCount++;
for (unsigned int j=0;j<ZT_MAX_PEER_NETWORK_PATHS;++j) {
if (_paths[i].p && _paths[j].p && _paths[i].p->address().ipsEqual2(_paths[j].p->address()) && i != j) {
duplicatePathsFound+=1;
break;
}
}
}
}
_uniqueAlivePathCount = (currAlivePathCount - (duplicatePathsFound / 2));
_lastMultipathCompatibilityCheck = now;
_localMultipathSupported = ((RR->node->getMultipathMode() != ZT_MULTIPATH_NONE) && (ZT_PROTO_VERSION > 9));
_remoteMultipathSupported = _vProto > 9;
// If both peers support multipath and more than one path exist, we can use multipath logic
_canUseMultipath = _localMultipathSupported && _remoteMultipathSupported && (_uniqueAlivePathCount > 1);
}
// Remove old flows
if (RR->sw->isFlowAware()) {
std::map<int64_t, struct Flow *>::iterator it = _flows.begin();
while (it != _flows.end()) {
if ((now - it->second->lastSend) > ZT_MULTIPATH_FLOW_EXPIRATION) {
fprintf(stderr, "forgetting flow %llx between this node and %llx (%lu active flow(s))\n",
it->first, this->_id.address().toInt(), _flows.size());
it = _flows.erase(it);
} else {
it++;
}
}
}
}
void Peer::sendACK(void *tPtr,const SharedPtr<Path> &path,const int64_t localSocket,const InetAddress &atAddress,int64_t now)
{
Packet outp(_id.address(),RR->identity.address(),Packet::VERB_ACK);
uint32_t bytesToAck = path->bytesToAck();
outp.append<uint32_t>(bytesToAck);
if (atAddress) {
outp.armor(_key,false);
RR->node->putPacket(tPtr,localSocket,atAddress,outp.data(),outp.size());
} else {
RR->sw->send(tPtr,outp,false);
}
path->sentAck(now);
}
void Peer::sendQOS_MEASUREMENT(void *tPtr,const SharedPtr<Path> &path,const int64_t localSocket,const InetAddress &atAddress,int64_t now)
{
const int64_t _now = RR->node->now();
Packet outp(_id.address(),RR->identity.address(),Packet::VERB_QOS_MEASUREMENT);
char qosData[ZT_PATH_MAX_QOS_PACKET_SZ];
int16_t len = path->generateQoSPacket(_now,qosData);
outp.append(qosData,len);
if (atAddress) {
outp.armor(_key,false);
RR->node->putPacket(tPtr,localSocket,atAddress,outp.data(),outp.size());
} else {
RR->sw->send(tPtr,outp,false);
}
path->sentQoS(now);
}
void Peer::sendHELLO(void *tPtr,const int64_t localSocket,const InetAddress &atAddress,int64_t now)
{
Packet outp(_id.address(),RR->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);
RR->identity.serialize(outp,false);
atAddress.serialize(outp);
outp.append((uint64_t)RR->topology->planetWorldId());
outp.append((uint64_t)RR->topology->planetWorldTimestamp());
const unsigned int startCryptedPortionAt = outp.size();
std::vector<World> moons(RR->topology->moons());
std::vector<uint64_t> moonsWanted(RR->topology->moonsWanted());
outp.append((uint16_t)(moons.size() + moonsWanted.size()));
for(std::vector<World>::const_iterator m(moons.begin());m!=moons.end();++m) {
outp.append((uint8_t)m->type());
outp.append((uint64_t)m->id());
outp.append((uint64_t)m->timestamp());
}
for(std::vector<uint64_t>::const_iterator m(moonsWanted.begin());m!=moonsWanted.end();++m) {
outp.append((uint8_t)World::TYPE_MOON);
outp.append(*m);
outp.append((uint64_t)0);
}
outp.cryptField(_key,startCryptedPortionAt,outp.size() - startCryptedPortionAt);
RR->node->expectReplyTo(outp.packetId());
if (atAddress) {
outp.armor(_key,false); // false == don't encrypt full payload, but add MAC
RR->node->putPacket(tPtr,localSocket,atAddress,outp.data(),outp.size());
} else {
RR->sw->send(tPtr,outp,false); // false == don't encrypt full payload, but add MAC
}
}
void Peer::attemptToContactAt(void *tPtr,const int64_t localSocket,const InetAddress &atAddress,int64_t now,bool sendFullHello)
{
if ( (!sendFullHello) && (_vProto >= 5) && (!((_vMajor == 1)&&(_vMinor == 1)&&(_vRevision == 0))) ) {
Packet outp(_id.address(),RR->identity.address(),Packet::VERB_ECHO);
RR->node->expectReplyTo(outp.packetId());
outp.armor(_key,true);
RR->node->putPacket(tPtr,localSocket,atAddress,outp.data(),outp.size());
} else {
sendHELLO(tPtr,localSocket,atAddress,now);
}
}
void Peer::tryMemorizedPath(void *tPtr,int64_t now)
{
if ((now - _lastTriedMemorizedPath) >= ZT_TRY_MEMORIZED_PATH_INTERVAL) {
_lastTriedMemorizedPath = now;
InetAddress mp;
if (RR->node->externalPathLookup(tPtr,_id.address(),-1,mp))
attemptToContactAt(tPtr,-1,mp,now,true);
}
}
unsigned int Peer::doPingAndKeepalive(void *tPtr,int64_t now)
{
unsigned int sent = 0;
Mutex::Lock _l(_paths_m);
processBackgroundPeerTasks(now);
// Emit traces regarding aggregate link status
if (_canUseMultipath) {
int alivePathCount = aggregateLinkPhysicalPathCount();
if ((now - _lastAggregateStatsReport) > ZT_PATH_AGGREGATE_STATS_REPORT_INTERVAL) {
_lastAggregateStatsReport = now;
if (alivePathCount) {
RR->t->peerLinkAggregateStatistics(NULL,*this);
}
} if (alivePathCount < 2 && _linkIsRedundant) {
_linkIsRedundant = !_linkIsRedundant;
RR->t->peerLinkNoLongerAggregate(NULL,*this);
} if (alivePathCount > 1 && !_linkIsRedundant) {
_linkIsRedundant = !_linkIsRedundant;
RR->t->peerLinkNoLongerAggregate(NULL,*this);
}
}
// Right now we only keep pinging links that have the maximum priority. The
// priority is used to track cluster redirections, meaning that when a cluster
// redirects us its redirect target links override all other links and we
// let those old links expire.
long maxPriority = 0;
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p)
maxPriority = std::max(_paths[i].priority,maxPriority);
else break;
}
const bool sendFullHello = ((now - _lastSentFullHello) >= ZT_PEER_PING_PERIOD);
_lastSentFullHello = now;
unsigned int j = 0;
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
// Clean expired and reduced priority paths
if ( ((now - _paths[i].lr) < ZT_PEER_PATH_EXPIRATION) && (_paths[i].priority == maxPriority) ) {
if ((sendFullHello)||(_paths[i].p->needsHeartbeat(now))) {
attemptToContactAt(tPtr,_paths[i].p->localSocket(),_paths[i].p->address(),now,sendFullHello);
_paths[i].p->sent(now);
sent |= (_paths[i].p->address().ss_family == AF_INET) ? 0x1 : 0x2;
}
if (i != j)
_paths[j] = _paths[i];
++j;
}
} else break;
}
if (canUseMultipath()) {
while(j < ZT_MAX_PEER_NETWORK_PATHS) {
_paths[j].lr = 0;
_paths[j].p.zero();
_paths[j].priority = 1;
++j;
}
}
return sent;
}
void Peer::clusterRedirect(void *tPtr,const SharedPtr<Path> &originatingPath,const InetAddress &remoteAddress,const int64_t now)
{
SharedPtr<Path> np(RR->topology->getPath(originatingPath->localSocket(),remoteAddress));
RR->t->peerRedirected(tPtr,0,*this,np);
attemptToContactAt(tPtr,originatingPath->localSocket(),remoteAddress,now,true);
{
Mutex::Lock _l(_paths_m);
// New priority is higher than the priority of the originating path (if known)
long newPriority = 1;
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
if (_paths[i].p == originatingPath) {
newPriority = _paths[i].priority;
break;
}
} else break;
}
newPriority += 2;
// Erase any paths with lower priority than this one or that are duplicate
// IPs and add this path.
unsigned int j = 0;
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
if ((_paths[i].priority >= newPriority)&&(!_paths[i].p->address().ipsEqual2(remoteAddress))) {
if (i != j)
_paths[j] = _paths[i];
++j;
}
}
}
if (j < ZT_MAX_PEER_NETWORK_PATHS) {
_paths[j].lr = now;
_paths[j].p = np;
_paths[j].priority = newPriority;
++j;
while (j < ZT_MAX_PEER_NETWORK_PATHS) {
_paths[j].lr = 0;
_paths[j].p.zero();
_paths[j].priority = 1;
++j;
}
}
}
}
void Peer::resetWithinScope(void *tPtr,InetAddress::IpScope scope,int inetAddressFamily,int64_t now)
{
Mutex::Lock _l(_paths_m);
for(unsigned int i=0;i<ZT_MAX_PEER_NETWORK_PATHS;++i) {
if (_paths[i].p) {
if ((_paths[i].p->address().ss_family == inetAddressFamily)&&(_paths[i].p->ipScope() == scope)) {
attemptToContactAt(tPtr,_paths[i].p->localSocket(),_paths[i].p->address(),now,false);
_paths[i].p->sent(now);
_paths[i].lr = 0; // path will not be used unless it speaks again
}
} else break;
}
}
} // namespace ZeroTier