mirror of
https://github.com/zerotier/ZeroTierOne.git
synced 2024-12-28 00:38:51 +00:00
693 lines
22 KiB
C++
693 lines
22 KiB
C++
/*
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* Copyright (c)2019 ZeroTier, Inc.
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*
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* Use of this software is governed by the Business Source License included
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* in the LICENSE.TXT file in the project's root directory.
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*
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* Change Date: 2023-01-01
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*
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* On the date above, in accordance with the Business Source License, use
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* of this software will be governed by version 2.0 of the Apache License.
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*/
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/****/
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#ifndef ZT_PATH_HPP
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#define ZT_PATH_HPP
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#include <stdint.h>
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#include <string.h>
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#include <stdlib.h>
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#include <stdexcept>
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#include <algorithm>
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#include "Constants.hpp"
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#include "InetAddress.hpp"
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#include "SharedPtr.hpp"
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#include "AtomicCounter.hpp"
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#include "Utils.hpp"
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#include "RingBuffer.hpp"
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#include "Packet.hpp"
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#include "../osdep/Phy.hpp"
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/**
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* Maximum return value of preferenceRank()
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*/
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#define ZT_PATH_MAX_PREFERENCE_RANK ((ZT_INETADDRESS_MAX_SCOPE << 1) | 1)
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namespace ZeroTier {
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class RuntimeEnvironment;
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/**
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* A path across the physical network
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*/
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class Path
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{
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friend class SharedPtr<Path>;
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Phy<Path *> *_phy;
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public:
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/**
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* Efficient unique key for paths in a Hashtable
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*/
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class HashKey
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{
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public:
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HashKey() {}
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HashKey(const int64_t l,const InetAddress &r)
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{
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if (r.ss_family == AF_INET) {
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_k[0] = (uint64_t)reinterpret_cast<const struct sockaddr_in *>(&r)->sin_addr.s_addr;
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_k[1] = (uint64_t)reinterpret_cast<const struct sockaddr_in *>(&r)->sin_port;
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_k[2] = (uint64_t)l;
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} else if (r.ss_family == AF_INET6) {
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memcpy(_k,reinterpret_cast<const struct sockaddr_in6 *>(&r)->sin6_addr.s6_addr,16);
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_k[2] = ((uint64_t)reinterpret_cast<const struct sockaddr_in6 *>(&r)->sin6_port << 32) ^ (uint64_t)l;
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} else {
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memcpy(_k,&r,std::min(sizeof(_k),sizeof(InetAddress)));
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_k[2] += (uint64_t)l;
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}
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}
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inline unsigned long hashCode() const { return (unsigned long)(_k[0] + _k[1] + _k[2]); }
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inline bool operator==(const HashKey &k) const { return ( (_k[0] == k._k[0]) && (_k[1] == k._k[1]) && (_k[2] == k._k[2]) ); }
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inline bool operator!=(const HashKey &k) const { return (!(*this == k)); }
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private:
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uint64_t _k[3];
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};
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Path() :
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_lastOut(0),
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_lastIn(0),
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_lastTrustEstablishedPacketReceived(0),
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_lastPathQualityComputeTime(0),
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_localSocket(-1),
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_latency(0xffff),
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_addr(),
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_ipScope(InetAddress::IP_SCOPE_NONE),
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_lastAck(0),
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_lastThroughputEstimation(0),
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_lastQoSMeasurement(0),
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_lastQoSRecordPurge(0),
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_unackedBytes(0),
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_expectingAckAsOf(0),
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_packetsReceivedSinceLastAck(0),
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_packetsReceivedSinceLastQoS(0),
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_maxLifetimeThroughput(0),
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_lastComputedMeanThroughput(0),
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_bytesAckedSinceLastThroughputEstimation(0),
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_lastComputedMeanLatency(0.0),
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_lastComputedPacketDelayVariance(0.0),
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_lastComputedPacketErrorRatio(0.0),
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_lastComputedPacketLossRatio(0),
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_lastComputedStability(0.0),
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_lastComputedRelativeQuality(0),
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_lastComputedThroughputDistCoeff(0.0),
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_lastAllocation(0)
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{
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memset(_ifname, 0, 16);
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memset(_addrString, 0, sizeof(_addrString));
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}
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Path(const int64_t localSocket,const InetAddress &addr) :
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_lastOut(0),
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_lastIn(0),
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_lastTrustEstablishedPacketReceived(0),
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_lastPathQualityComputeTime(0),
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_localSocket(localSocket),
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_latency(0xffff),
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_addr(addr),
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_ipScope(addr.ipScope()),
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_lastAck(0),
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_lastThroughputEstimation(0),
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_lastQoSMeasurement(0),
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_lastQoSRecordPurge(0),
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_unackedBytes(0),
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_expectingAckAsOf(0),
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_packetsReceivedSinceLastAck(0),
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_packetsReceivedSinceLastQoS(0),
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_maxLifetimeThroughput(0),
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_lastComputedMeanThroughput(0),
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_bytesAckedSinceLastThroughputEstimation(0),
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_lastComputedMeanLatency(0.0),
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_lastComputedPacketDelayVariance(0.0),
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_lastComputedPacketErrorRatio(0.0),
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_lastComputedPacketLossRatio(0),
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_lastComputedStability(0.0),
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_lastComputedRelativeQuality(0),
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_lastComputedThroughputDistCoeff(0.0),
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_lastAllocation(0)
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{
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memset(_ifname, 0, 16);
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memset(_addrString, 0, sizeof(_addrString));
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if (_localSocket != -1) {
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_phy->getIfName((PhySocket *) ((uintptr_t) _localSocket), _ifname, 16);
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}
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}
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/**
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* Called when a packet is received from this remote path, regardless of content
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*
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* @param t Time of receive
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*/
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inline void received(const uint64_t t) { _lastIn = t; }
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/**
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* Set time last trusted packet was received (done in Peer::received())
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*/
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inline void trustedPacketReceived(const uint64_t t) { _lastTrustEstablishedPacketReceived = t; }
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/**
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* Send a packet via this path (last out time is also updated)
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*
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* @param RR Runtime environment
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* @param tPtr Thread pointer to be handed through to any callbacks called as a result of this call
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* @param data Packet data
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* @param len Packet length
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* @param now Current time
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* @return True if transport reported success
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*/
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bool send(const RuntimeEnvironment *RR,void *tPtr,const void *data,unsigned int len,int64_t now);
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/**
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* Manually update last sent time
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*
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* @param t Time of send
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*/
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inline void sent(const int64_t t) { _lastOut = t; }
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/**
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* Update path latency with a new measurement
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*
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* @param l Measured latency
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*/
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inline void updateLatency(const unsigned int l, int64_t now)
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{
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unsigned int pl = _latency;
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if (pl < 0xffff) {
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_latency = (pl + l) / 2;
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}
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else {
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_latency = l;
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}
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_latencySamples.push(l);
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}
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/**
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* @return Local socket as specified by external code
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*/
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inline int64_t localSocket() const { return _localSocket; }
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/**
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* @return Physical address
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*/
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inline const InetAddress &address() const { return _addr; }
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/**
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* @return IP scope -- faster shortcut for address().ipScope()
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*/
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inline InetAddress::IpScope ipScope() const { return _ipScope; }
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/**
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* @return True if path has received a trust established packet (e.g. common network membership) in the past ZT_TRUST_EXPIRATION ms
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*/
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inline bool trustEstablished(const int64_t now) const { return ((now - _lastTrustEstablishedPacketReceived) < ZT_TRUST_EXPIRATION); }
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/**
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* @return Preference rank, higher == better
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*/
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inline unsigned int preferenceRank() const
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{
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// This causes us to rank paths in order of IP scope rank (see InetAdddress.hpp) but
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// within each IP scope class to prefer IPv6 over IPv4.
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return ( ((unsigned int)_ipScope << 1) | (unsigned int)(_addr.ss_family == AF_INET6) );
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}
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/**
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* Check whether this address is valid for a ZeroTier path
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*
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* This checks the address type and scope against address types and scopes
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* that we currently support for ZeroTier communication.
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*
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* @param a Address to check
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* @return True if address is good for ZeroTier path use
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*/
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static inline bool isAddressValidForPath(const InetAddress &a)
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{
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if ((a.ss_family == AF_INET)||(a.ss_family == AF_INET6)) {
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switch(a.ipScope()) {
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/* Note: we don't do link-local at the moment. Unfortunately these
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* cause several issues. The first is that they usually require a
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* device qualifier, which we don't handle yet and can't portably
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* push in PUSH_DIRECT_PATHS. The second is that some OSes assign
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* these very ephemerally or otherwise strangely. So we'll use
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* private, pseudo-private, shared (e.g. carrier grade NAT), or
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* global IP addresses. */
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case InetAddress::IP_SCOPE_PRIVATE:
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case InetAddress::IP_SCOPE_PSEUDOPRIVATE:
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case InetAddress::IP_SCOPE_SHARED:
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case InetAddress::IP_SCOPE_GLOBAL:
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if (a.ss_family == AF_INET6) {
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// TEMPORARY HACK: for now, we are going to blacklist he.net IPv6
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// tunnels due to very spotty performance and low MTU issues over
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// these IPv6 tunnel links.
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const uint8_t *ipd = reinterpret_cast<const uint8_t *>(reinterpret_cast<const struct sockaddr_in6 *>(&a)->sin6_addr.s6_addr);
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if ((ipd[0] == 0x20)&&(ipd[1] == 0x01)&&(ipd[2] == 0x04)&&(ipd[3] == 0x70))
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return false;
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}
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return true;
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default:
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return false;
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}
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}
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return false;
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}
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/**
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* @return Latency or 0xffff if unknown
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*/
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inline unsigned int latency() const { return _latency; }
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/**
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* @return Path quality -- lower is better
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*/
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inline long quality(const int64_t now) const
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{
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const int l = (long)_latency;
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const int age = (long)std::min((now - _lastIn),(int64_t)(ZT_PATH_HEARTBEAT_PERIOD * 10)); // set an upper sanity limit to avoid overflow
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return (((age < (ZT_PATH_HEARTBEAT_PERIOD + 5000)) ? l : (l + 0xffff + age)) * (long)((ZT_INETADDRESS_MAX_SCOPE - _ipScope) + 1));
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}
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/**
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* Record statistics on outgoing packets. Used later to estimate QoS metrics.
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*
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* @param now Current time
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* @param packetId ID of packet
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* @param payloadLength Length of payload
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* @param verb Packet verb
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*/
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inline void recordOutgoingPacket(int64_t now, int64_t packetId, uint16_t payloadLength, Packet::Verb verb)
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{
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Mutex::Lock _l(_statistics_m);
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if (verb != Packet::VERB_ACK && verb != Packet::VERB_QOS_MEASUREMENT) {
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if ((packetId & (ZT_PATH_QOS_ACK_PROTOCOL_DIVISOR - 1)) == 0) {
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_unackedBytes += payloadLength;
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// Take note that we're expecting a VERB_ACK on this path as of a specific time
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_expectingAckAsOf = ackAge(now) > ZT_PATH_ACK_INTERVAL ? _expectingAckAsOf : now;
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if (_outQoSRecords.size() < ZT_PATH_MAX_OUTSTANDING_QOS_RECORDS) {
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_outQoSRecords[packetId] = now;
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}
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}
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}
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}
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/**
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* Record statistics on incoming packets. Used later to estimate QoS metrics.
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*
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* @param now Current time
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* @param packetId ID of packet
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* @param payloadLength Length of payload
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* @param verb Packet verb
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*/
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inline void recordIncomingPacket(int64_t now, int64_t packetId, uint16_t payloadLength, Packet::Verb verb)
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{
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Mutex::Lock _l(_statistics_m);
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if (verb != Packet::VERB_ACK && verb != Packet::VERB_QOS_MEASUREMENT) {
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if ((packetId & (ZT_PATH_QOS_ACK_PROTOCOL_DIVISOR - 1)) == 0) {
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_inACKRecords[packetId] = payloadLength;
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_packetsReceivedSinceLastAck++;
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_inQoSRecords[packetId] = now;
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_packetsReceivedSinceLastQoS++;
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}
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_packetValiditySamples.push(true);
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}
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}
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/**
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* Record that we've received a VERB_ACK on this path, also compute throughput if required.
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*
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* @param now Current time
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* @param ackedBytes Number of bytes acknowledged by other peer
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*/
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inline void receivedAck(int64_t now, int32_t ackedBytes)
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{
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_expectingAckAsOf = 0;
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_unackedBytes = (ackedBytes > _unackedBytes) ? 0 : _unackedBytes - ackedBytes;
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int64_t timeSinceThroughputEstimate = (now - _lastThroughputEstimation);
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if (timeSinceThroughputEstimate >= ZT_PATH_THROUGHPUT_MEASUREMENT_INTERVAL) {
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uint64_t throughput = (uint64_t)((float)(_bytesAckedSinceLastThroughputEstimation * 8) / ((float)timeSinceThroughputEstimate / (float)1000));
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_throughputSamples.push(throughput);
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_maxLifetimeThroughput = throughput > _maxLifetimeThroughput ? throughput : _maxLifetimeThroughput;
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_lastThroughputEstimation = now;
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_bytesAckedSinceLastThroughputEstimation = 0;
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} else {
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_bytesAckedSinceLastThroughputEstimation += ackedBytes;
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}
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}
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/**
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* @return Number of bytes this peer is responsible for ACKing since last ACK
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*/
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inline int32_t bytesToAck()
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{
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Mutex::Lock _l(_statistics_m);
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int32_t bytesToAck = 0;
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std::map<uint64_t,uint16_t>::iterator it = _inACKRecords.begin();
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while (it != _inACKRecords.end()) {
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bytesToAck += it->second;
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it++;
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}
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return bytesToAck;
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}
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/**
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* @return Number of bytes thus far sent that have not been acknowledged by the remote peer
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*/
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inline int64_t unackedSentBytes()
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{
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return _unackedBytes;
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}
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/**
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* Account for the fact that an ACK was just sent. Reset counters, timers, and clear statistics buffers
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*
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* @param Current time
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*/
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inline void sentAck(int64_t now)
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{
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Mutex::Lock _l(_statistics_m);
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_inACKRecords.clear();
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_packetsReceivedSinceLastAck = 0;
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_lastAck = now;
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}
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/**
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* Receive QoS data, match with recorded egress times from this peer, compute latency
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* estimates.
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*
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* @param now Current time
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* @param count Number of records
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* @param rx_id table of packet IDs
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* @param rx_ts table of holding times
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*/
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inline void receivedQoS(int64_t now, int count, uint64_t *rx_id, uint16_t *rx_ts)
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{
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Mutex::Lock _l(_statistics_m);
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// Look up egress times and compute latency values for each record
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std::map<uint64_t,uint64_t>::iterator it;
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for (int j=0; j<count; j++) {
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it = _outQoSRecords.find(rx_id[j]);
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if (it != _outQoSRecords.end()) {
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uint16_t rtt = (uint16_t)(now - it->second);
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uint16_t rtt_compensated = rtt - rx_ts[j];
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uint16_t latency = rtt_compensated / 2;
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updateLatency(latency, now);
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_outQoSRecords.erase(it);
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}
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}
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}
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/**
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* Generate the contents of a VERB_QOS_MEASUREMENT packet.
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*
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* @param now Current time
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* @param qosBuffer destination buffer
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* @return Size of payload
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*/
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inline int32_t generateQoSPacket(int64_t now, char *qosBuffer)
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{
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Mutex::Lock _l(_statistics_m);
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int32_t len = 0;
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std::map<uint64_t,uint64_t>::iterator it = _inQoSRecords.begin();
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int i=0;
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while (i<_packetsReceivedSinceLastQoS && it != _inQoSRecords.end()) {
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uint64_t id = it->first;
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memcpy(qosBuffer, &id, sizeof(uint64_t));
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qosBuffer+=sizeof(uint64_t);
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uint16_t holdingTime = (uint16_t)(now - it->second);
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memcpy(qosBuffer, &holdingTime, sizeof(uint16_t));
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qosBuffer+=sizeof(uint16_t);
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len+=sizeof(uint64_t)+sizeof(uint16_t);
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_inQoSRecords.erase(it++);
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i++;
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}
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return len;
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}
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/**
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* Account for the fact that a VERB_QOS_MEASUREMENT was just sent. Reset timers.
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*
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* @param Current time
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*/
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inline void sentQoS(int64_t now) {
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_packetsReceivedSinceLastQoS = 0;
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_lastQoSMeasurement = now;
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}
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/**
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* @param now Current time
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* @return Whether an ACK (VERB_ACK) packet needs to be emitted at this time
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*/
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inline bool needsToSendAck(int64_t now) {
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return ((now - _lastAck) >= ZT_PATH_ACK_INTERVAL ||
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(_packetsReceivedSinceLastAck == ZT_PATH_QOS_TABLE_SIZE)) && _packetsReceivedSinceLastAck;
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}
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/**
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* @param now Current time
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* @return Whether a QoS (VERB_QOS_MEASUREMENT) packet needs to be emitted at this time
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*/
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inline bool needsToSendQoS(int64_t now) {
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return ((_packetsReceivedSinceLastQoS >= ZT_PATH_QOS_TABLE_SIZE) ||
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((now - _lastQoSMeasurement) > ZT_PATH_QOS_INTERVAL)) && _packetsReceivedSinceLastQoS;
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}
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/**
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* How much time has elapsed since we've been expecting a VERB_ACK on this path. This value
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* is used to determine a more relevant path "age". This lets us penalize paths which are no
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* longer ACKing, but not those that simple aren't being used to carry traffic at the
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* current time.
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*/
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inline int64_t ackAge(int64_t now) { return _expectingAckAsOf ? now - _expectingAckAsOf : 0; }
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/**
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* The maximum observed throughput (in bits/s) for this path
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*/
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inline uint64_t maxLifetimeThroughput() { return _maxLifetimeThroughput; }
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/**
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* @return The mean throughput (in bits/s) of this link
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*/
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inline uint64_t meanThroughput() { return _lastComputedMeanThroughput; }
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/**
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* Assign a new relative quality value for this path in the aggregate link
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*
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* @param rq Quality of this path in comparison to other paths available to this peer
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*/
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inline void updateRelativeQuality(float rq) { _lastComputedRelativeQuality = rq; }
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/**
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* @return Quality of this path compared to others in the aggregate link
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*/
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inline float relativeQuality() { return _lastComputedRelativeQuality; }
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/**
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* Assign a new allocation value for this path in the aggregate link
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*
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* @param allocation Percentage of traffic to be sent over this path to a peer
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*/
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inline void updateComponentAllocationOfAggregateLink(unsigned char allocation) { _lastAllocation = allocation; }
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/**
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* @return Percentage of traffic allocated to this path in the aggregate link
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*/
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inline unsigned char allocation() { return _lastAllocation; }
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/**
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* @return Stability estimates can become expensive to compute, we cache the most recent result.
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*/
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inline float lastComputedStability() { return _lastComputedStability; }
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/**
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* @return A pointer to a cached copy of the human-readable name of the interface this Path's localSocket is bound to
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*/
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inline char *getName() { return _ifname; }
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/**
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* @return Packet delay variance
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*/
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inline float packetDelayVariance() { return _lastComputedPacketDelayVariance; }
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/**
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* @return Previously-computed mean latency
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*/
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inline float meanLatency() { return _lastComputedMeanLatency; }
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/**
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* @return Packet loss rate (PLR)
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*/
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inline float packetLossRatio() { return _lastComputedPacketLossRatio; }
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/**
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* @return Packet error ratio (PER)
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*/
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inline float packetErrorRatio() { return _lastComputedPacketErrorRatio; }
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/**
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* Record an invalid incoming packet. This packet failed MAC/compression/cipher checks and will now
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* contribute to a Packet Error Ratio (PER).
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*/
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inline void recordInvalidPacket() { _packetValiditySamples.push(false); }
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/**
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* @return A pointer to a cached copy of the address string for this Path (For debugging only)
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*/
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inline char *getAddressString() { return _addrString; }
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/**
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* @return The current throughput disturbance coefficient
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*/
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inline float throughputDisturbanceCoefficient() { return _lastComputedThroughputDistCoeff; }
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/**
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* Compute and cache stability and performance metrics. The resultant stability coefficient is a measure of how "well behaved"
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* this path is. This figure is substantially different from (but required for the estimation of the path's overall "quality".
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*
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* @param now Current time
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*/
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inline void processBackgroundPathMeasurements(const int64_t now)
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{
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if (now - _lastPathQualityComputeTime > ZT_PATH_QUALITY_COMPUTE_INTERVAL) {
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Mutex::Lock _l(_statistics_m);
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_lastPathQualityComputeTime = now;
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address().toString(_addrString);
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_lastComputedMeanLatency = _latencySamples.mean();
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_lastComputedPacketDelayVariance = _latencySamples.stddev(); // Similar to "jitter" (SEE: RFC 3393, RFC 4689)
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_lastComputedMeanThroughput = (uint64_t)_throughputSamples.mean();
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// If no packet validity samples, assume PER==0
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_lastComputedPacketErrorRatio = 1 - (_packetValiditySamples.count() ? _packetValiditySamples.mean() : 1);
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// Compute path stability
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// Normalize measurements with wildly different ranges into a reasonable range
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float normalized_pdv = Utils::normalize(_lastComputedPacketDelayVariance, 0, ZT_PATH_MAX_PDV, 0, 10);
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float normalized_la = Utils::normalize(_lastComputedMeanLatency, 0, ZT_PATH_MAX_MEAN_LATENCY, 0, 10);
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float throughput_cv = _throughputSamples.mean() > 0 ? _throughputSamples.stddev() / _throughputSamples.mean() : 1;
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// Form an exponential cutoff and apply contribution weights
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float pdv_contrib = expf((-1.0f)*normalized_pdv) * (float)ZT_PATH_CONTRIB_PDV;
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float latency_contrib = expf((-1.0f)*normalized_la) * (float)ZT_PATH_CONTRIB_LATENCY;
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// Throughput Disturbance Coefficient
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float throughput_disturbance_contrib = expf((-1.0f)*throughput_cv) * (float)ZT_PATH_CONTRIB_THROUGHPUT_DISTURBANCE;
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_throughputDisturbanceSamples.push(throughput_cv);
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_lastComputedThroughputDistCoeff = _throughputDisturbanceSamples.mean();
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// Obey user-defined ignored contributions
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pdv_contrib = ZT_PATH_CONTRIB_PDV > 0.0 ? pdv_contrib : 1;
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latency_contrib = ZT_PATH_CONTRIB_LATENCY > 0.0 ? latency_contrib : 1;
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throughput_disturbance_contrib = ZT_PATH_CONTRIB_THROUGHPUT_DISTURBANCE > 0.0 ? throughput_disturbance_contrib : 1;
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// Stability
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_lastComputedStability = pdv_contrib + latency_contrib + throughput_disturbance_contrib;
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_lastComputedStability *= 1 - _lastComputedPacketErrorRatio;
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// Prevent QoS records from sticking around for too long
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std::map<uint64_t,uint64_t>::iterator it = _outQoSRecords.begin();
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while (it != _outQoSRecords.end()) {
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// Time since egress of tracked packet
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if ((now - it->second) >= ZT_PATH_QOS_TIMEOUT) {
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_outQoSRecords.erase(it++);
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} else { it++; }
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}
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}
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}
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/**
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* @return True if this path is alive (receiving heartbeats)
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*/
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inline bool alive(const int64_t now) const { return ((now - _lastIn) < (ZT_PATH_HEARTBEAT_PERIOD + 5000)); }
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/**
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* @return True if this path needs a heartbeat
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*/
|
|
inline bool needsHeartbeat(const int64_t now) const { return ((now - _lastOut) >= ZT_PATH_HEARTBEAT_PERIOD); }
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/**
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* @return Last time we sent something
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*/
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inline int64_t lastOut() const { return _lastOut; }
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/**
|
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* @return Last time we received anything
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*/
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inline int64_t lastIn() const { return _lastIn; }
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/**
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* @return Time last trust-established packet was received
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*/
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inline int64_t lastTrustEstablishedPacketReceived() const { return _lastTrustEstablishedPacketReceived; }
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private:
|
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Mutex _statistics_m;
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|
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volatile int64_t _lastOut;
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volatile int64_t _lastIn;
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volatile int64_t _lastTrustEstablishedPacketReceived;
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volatile int64_t _lastPathQualityComputeTime;
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int64_t _localSocket;
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volatile unsigned int _latency;
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InetAddress _addr;
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InetAddress::IpScope _ipScope; // memoize this since it's a computed value checked often
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AtomicCounter __refCount;
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std::map<uint64_t,uint64_t> _outQoSRecords; // id:egress_time
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std::map<uint64_t,uint64_t> _inQoSRecords; // id:now
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std::map<uint64_t,uint16_t> _inACKRecords; // id:len
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|
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int64_t _lastAck;
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int64_t _lastThroughputEstimation;
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int64_t _lastQoSMeasurement;
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int64_t _lastQoSRecordPurge;
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|
|
int64_t _unackedBytes;
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|
int64_t _expectingAckAsOf;
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|
int16_t _packetsReceivedSinceLastAck;
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|
int16_t _packetsReceivedSinceLastQoS;
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|
|
|
uint64_t _maxLifetimeThroughput;
|
|
uint64_t _lastComputedMeanThroughput;
|
|
uint64_t _bytesAckedSinceLastThroughputEstimation;
|
|
|
|
float _lastComputedMeanLatency;
|
|
float _lastComputedPacketDelayVariance;
|
|
|
|
float _lastComputedPacketErrorRatio;
|
|
float _lastComputedPacketLossRatio;
|
|
|
|
// cached estimates
|
|
float _lastComputedStability;
|
|
float _lastComputedRelativeQuality;
|
|
float _lastComputedThroughputDistCoeff;
|
|
unsigned char _lastAllocation;
|
|
|
|
// cached human-readable strings for tracing purposes
|
|
char _ifname[16];
|
|
char _addrString[256];
|
|
|
|
RingBuffer<uint64_t,ZT_PATH_QUALITY_METRIC_WIN_SZ> _throughputSamples;
|
|
RingBuffer<uint32_t,ZT_PATH_QUALITY_METRIC_WIN_SZ> _latencySamples;
|
|
RingBuffer<bool,ZT_PATH_QUALITY_METRIC_WIN_SZ> _packetValiditySamples;
|
|
RingBuffer<float,ZT_PATH_QUALITY_METRIC_WIN_SZ> _throughputDisturbanceSamples;
|
|
};
|
|
|
|
} // namespace ZeroTier
|
|
|
|
#endif
|