ZeroTierOne/core/Path.hpp

247 lines
6.3 KiB
C++

/*
* Copyright (c)2013-2021 ZeroTier, Inc.
*
* Use of this software is governed by the Business Source License included
* in the LICENSE.TXT file in the project's root directory.
*
* Change Date: 2026-01-01
*
* On the date above, in accordance with the Business Source License, use
* of this software will be governed by version 2.0 of the Apache License.
*/
/****/
#ifndef ZT_PATH_HPP
#define ZT_PATH_HPP
#include "Constants.hpp"
#include "InetAddress.hpp"
#include "SharedPtr.hpp"
#include "Utils.hpp"
#include "Mutex.hpp"
#include "Meter.hpp"
#include "Containers.hpp"
#include "CallContext.hpp"
namespace ZeroTier {
class RuntimeEnvironment;
template< unsigned int MF, unsigned int MFP, unsigned int GCT, unsigned int GCS, typename P >
class Defragmenter;
/**
* A path across the physical network
*/
class Path
{
friend class SharedPtr< Path >;
// Allow defragmenter to access fragment-in-flight info stored in Path for performance reasons.
template< unsigned int MF, unsigned int MFP, unsigned int GCT, unsigned int GCS, typename P >
friend
class Defragmenter;
public:
/**
* Map key for paths designed for very fast lookup
*/
class Key
{
public:
/**
* Construct key with undefined value
*/
ZT_INLINE Key() noexcept
{}
ZT_INLINE Key(const Key &k) noexcept: m_hashCode(k.m_hashCode), m_v664(k.m_v664), m_port(k.m_port)
{}
ZT_INLINE Key(const InetAddress &ip) noexcept
{
const unsigned int family = ip.as.sa.sa_family;
if (family == AF_INET) {
const uint16_t p = (uint16_t)ip.as.sa_in.sin_port;
m_hashCode = Utils::hash64((((uint64_t)ip.as.sa_in.sin_addr.s_addr) << 16U) ^ ((uint64_t)p) ^ Utils::s_mapNonce);
m_v664 = 0; // IPv6 /64 is 0 for IPv4
m_port = p;
} else {
if (likely(family == AF_INET6)) {
const uint64_t a = Utils::loadMachineEndian< uint64_t >(reinterpret_cast<const uint8_t *>(ip.as.sa_in6.sin6_addr.s6_addr));
const uint64_t b = Utils::loadMachineEndian< uint64_t >(reinterpret_cast<const uint8_t *>(ip.as.sa_in6.sin6_addr.s6_addr) + 8);
const uint16_t p = ip.as.sa_in6.sin6_port;
m_hashCode = Utils::hash64(a ^ b ^ ((uint64_t)p) ^ Utils::s_mapNonce);
m_v664 = a; // IPv6 /64
m_port = p;
} else {
// This isn't reachable since only IPv4 and IPv6 are used with InetAddress, but implement
// something here for technical completeness.
m_hashCode = Utils::fnv1a32(&ip, sizeof(InetAddress));
m_v664 = Utils::fnv1a32(ip.as.sa.sa_data, sizeof(ip.as.sa.sa_data));
m_port = (uint16_t)family;
}
}
}
ZT_INLINE Key &operator=(const Key &k) noexcept
{
m_hashCode = k.m_hashCode;
m_v664 = k.m_v664;
m_port = k.m_port;
return *this;
}
ZT_INLINE unsigned long hashCode() const noexcept
{ return (unsigned long)m_hashCode; }
ZT_INLINE bool operator==(const Key &k) const noexcept
{ return (m_hashCode == k.m_hashCode) && (m_v664 == k.m_v664) && (m_port == k.m_port); }
ZT_INLINE bool operator!=(const Key &k) const noexcept
{ return (!(*this == k)); }
ZT_INLINE bool operator<(const Key &k) const noexcept
{
if (m_hashCode < k.m_hashCode) {
return true;
} else if (m_hashCode == k.m_hashCode) {
if (m_v664 < k.m_v664) {
return true;
} else if (m_v664 == k.m_v664) {
return (m_port < k.m_port);
}
}
return false;
}
ZT_INLINE bool operator>(const Key &k) const noexcept
{ return (k < *this); }
ZT_INLINE bool operator<=(const Key &k) const noexcept
{ return !(k < *this); }
ZT_INLINE bool operator>=(const Key &k) const noexcept
{ return !(*this < k); }
private:
uint64_t m_hashCode;
uint64_t m_v664;
uint16_t m_port;
};
ZT_INLINE Path(const int64_t l, const InetAddress &r) noexcept:
m_localSocket(l),
m_lastIn(0),
m_lastOut(0),
m_latency(-1),
m_addr(r)
{}
/**
* Send a packet via this path (last out time is also updated)
*
* @param data Packet data
* @param len Packet length
* @return True if transport reported success
*/
bool send(const RuntimeEnvironment *RR, CallContext &cc, const void *data, unsigned int len) noexcept;
/**
* Explicitly update last sent time
*
* @param now Time of send
* @param bytes Bytes sent
*/
ZT_INLINE void sent(const CallContext &cc, const unsigned int bytes) noexcept
{
m_lastOut.store(cc.ticks, std::memory_order_relaxed);
m_outMeter.log(cc.ticks, bytes);
}
/**
* Called when a packet is received from this remote path, regardless of content
*
* @param now Time of receive
* @param bytes Bytes received
*/
ZT_INLINE void received(const CallContext &cc, const unsigned int bytes) noexcept
{
m_lastIn.store(cc.ticks, std::memory_order_relaxed);
m_inMeter.log(cc.ticks, bytes);
}
/**
* Update latency with a new measurement
*
* @param newMeasurement New latency measurement in milliseconds
*/
ZT_INLINE void updateLatency(const unsigned int newMeasurement) noexcept
{
int lat = m_latency;
if (likely(lat > 0)) {
m_latency = (lat + newMeasurement) / 2;
} else {
m_latency = newMeasurement;
}
}
/**
* @return Latency in milliseconds or -1 if unknown
*/
ZT_INLINE int latency() const noexcept
{ return m_latency; }
/**
* Check path aliveness
*
* @param now Current time
*/
ZT_INLINE bool alive(const CallContext &cc) const noexcept
{ return ((cc.ticks - m_lastIn.load()) < ZT_PATH_ALIVE_TIMEOUT); }
/**
* @return Physical address
*/
ZT_INLINE const InetAddress &address() const noexcept
{ return m_addr; }
/**
* @return Local socket as specified by external code
*/
ZT_INLINE int64_t localSocket() const noexcept
{ return m_localSocket; }
/**
* @return Last time we received anything
*/
ZT_INLINE int64_t lastIn() const noexcept
{ return m_lastIn.load(); }
/**
* @return Last time we sent something
*/
ZT_INLINE int64_t lastOut() const noexcept
{ return m_lastOut.load(); }
private:
const int64_t m_localSocket;
std::atomic< int64_t > m_lastIn;
std::atomic< int64_t > m_lastOut;
std::atomic< int > m_latency;
const InetAddress m_addr;
Meter<> m_inMeter;
Meter<> m_outMeter;
// These fields belong to Defragmenter but are kept in Path for performance
// as it's much faster this way than having Defragmenter maintain another
// mapping from paths to inbound message IDs.
Set< uint64_t > m_inboundFragmentedMessages;
Mutex m_inboundFragmentedMessages_l;
std::atomic< int > __refCount;
};
} // namespace ZeroTier
#endif