/* * ZeroTier One - Network Virtualization Everywhere * Copyright (C) 2011-2016 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 . */ #ifndef ZT_PEER_HPP #define ZT_PEER_HPP #include #include "Constants.hpp" #include #include #include #include #include "../include/ZeroTierOne.h" #include "RuntimeEnvironment.hpp" #include "Path.hpp" #include "Address.hpp" #include "Utils.hpp" #include "Identity.hpp" #include "InetAddress.hpp" #include "Packet.hpp" #include "SharedPtr.hpp" #include "AtomicCounter.hpp" #include "Hashtable.hpp" #include "Mutex.hpp" #include "NonCopyable.hpp" namespace ZeroTier { /** * Peer on P2P Network (virtual layer 1) */ class Peer : NonCopyable { friend class SharedPtr; private: Peer() {} // disabled to prevent bugs -- should not be constructed uninitialized public: ~Peer() { Utils::burn(_key,sizeof(_key)); } /** * Construct a new peer * * @param renv Runtime environment * @param myIdentity Identity of THIS node (for key agreement) * @param peerIdentity Identity of peer * @throws std::runtime_error Key agreement with peer's identity failed */ Peer(const RuntimeEnvironment *renv,const Identity &myIdentity,const Identity &peerIdentity); /** * @return Time peer record was last used in any way */ inline uint64_t lastUsed() const throw() { return _lastUsed; } /** * Log a use of this peer record (done by Topology when peers are looked up) * * @param now New time of last use */ inline void use(uint64_t now) throw() { _lastUsed = now; } /** * @return This peer's ZT address (short for identity().address()) */ inline const Address &address() const throw() { return _id.address(); } /** * @return This peer's identity */ inline const Identity &identity() const throw() { return _id; } /** * Log receipt of an authenticated packet * * This is called by the decode pipe when a packet is proven to be authentic * and appears to be valid. * * @param RR Runtime environment * @param localAddr Local address * @param remoteAddr Internet address of sender * @param hops ZeroTier (not IP) hops * @param packetId Packet ID * @param verb Packet verb * @param inRePacketId Packet ID in reply to (default: none) * @param inReVerb Verb in reply to (for OK/ERROR, default: VERB_NOP) */ void received( const InetAddress &localAddr, const InetAddress &remoteAddr, unsigned int hops, uint64_t packetId, Packet::Verb verb, uint64_t inRePacketId = 0, Packet::Verb inReVerb = Packet::VERB_NOP); /** * Get the current best direct path to this peer * * @param now Current time * @return Best path or NULL if there are no active direct paths */ inline Path *getBestPath(uint64_t now) { return _getBestPath(now); } /** * @param now Current time * @param addr Remote address * @return True if we have an active path to this destination */ inline bool hasActivePathTo(uint64_t now,const InetAddress &addr) const { for(unsigned int p=0;p<_numPaths;++p) { if ((_paths[p].active(now))&&(_paths[p].address() == addr)) return true; } return false; } /** * Set all paths in the same ss_family that are not this one to cluster suboptimal * * Addresses in other families are not affected. * * @param addr Address to make exclusive */ inline void setClusterOptimalPathForAddressFamily(const InetAddress &addr) { for(unsigned int p=0;p<_numPaths;++p) { if (_paths[p].address().ss_family == addr.ss_family) { _paths[p].setClusterSuboptimal(_paths[p].address() != addr); } } } /** * Send via best path * * @param data Packet data * @param len Packet length * @param now Current time * @return Path used on success or NULL on failure */ inline Path *send(const void *data,unsigned int len,uint64_t now) { Path *const bestPath = getBestPath(now); if (bestPath) { if (bestPath->send(RR,data,len,now)) return bestPath; } return (Path *)0; } /** * Send a HELLO to this peer at a specified physical address * * This does not update any statistics. It's used to send initial HELLOs * for NAT traversal and path verification. * * @param localAddr Local address * @param atAddress Destination address * @param now Current time * @param ttl Desired IP TTL (default: 0 to leave alone) */ void sendHELLO(const InetAddress &localAddr,const InetAddress &atAddress,uint64_t now,unsigned int ttl = 0); /** * Send pings or keepalives depending on configured timeouts * * @param now Current time * @param inetAddressFamily Keep this address family alive, or 0 to simply pick current best ignoring family * @return True if at least one direct path seems alive */ bool doPingAndKeepalive(uint64_t now,int inetAddressFamily); /** * Push direct paths back to self if we haven't done so in the configured timeout * * @param localAddr Local address * @param toAddress Remote address to send push to (usually from path) * @param now Current time * @param force If true, push regardless of rate limit * @param includePrivatePaths If true, include local interface address paths (should only be done to peers with a trust relationship) * @return True if something was actually sent */ bool pushDirectPaths(const InetAddress &localAddr,const InetAddress &toAddress,uint64_t now,bool force,bool includePrivatePaths); /** * @return All known direct paths to this peer (active or inactive) */ inline std::vector paths() const { std::vector pp; for(unsigned int p=0,np=_numPaths;p= ZT_PEER_ACTIVITY_TIMEOUT) return (~(unsigned int)0); unsigned int l = _latency; if (!l) l = 0xffff; return (l * (((unsigned int)tsr / (ZT_PEER_DIRECT_PING_DELAY + 1000)) + 1)); } /** * Update latency with a new direct measurment * * @param l Direct latency measurment in ms */ inline void addDirectLatencyMeasurment(unsigned int l) { unsigned int ol = _latency; if ((ol > 0)&&(ol < 10000)) _latency = (ol + std::min(l,(unsigned int)65535)) / 2; else _latency = std::min(l,(unsigned int)65535); } /** * @param now Current time * @return True if this peer has at least one active direct path */ inline bool hasActiveDirectPath(uint64_t now) const { for(unsigned int p=0;p<_numPaths;++p) { if (_paths[p].active(now)) return true; } return false; } #ifdef ZT_ENABLE_CLUSTER /** * @param now Current time * @return True if this peer has at least one active direct path that is not cluster-suboptimal */ inline bool hasClusterOptimalPath(uint64_t now) const { for(unsigned int p=0,np=_numPaths;p 0)||(_vMinor > 0)||(_vRevision > 0)); } /** * Get most recently active path addresses for IPv4 and/or IPv6 * * Note that v4 and v6 are not modified if they are not found, so * initialize these to a NULL address to be able to check. * * @param now Current time * @param v4 Result parameter to receive active IPv4 address, if any * @param v6 Result parameter to receive active IPv6 address, if any */ void getBestActiveAddresses(uint64_t now,InetAddress &v4,InetAddress &v6) const; /** * Perform periodic cleaning operations * * @param now Current time */ void clean(uint64_t now); /** * Update direct path push stats and return true if we should respond * * This is a circuit breaker to make VERB_PUSH_DIRECT_PATHS not particularly * useful as a DDOS amplification attack vector. Otherwise a malicious peer * could send loads of these and cause others to bombard arbitrary IPs with * traffic. * * @param now Current time * @return True if we should respond */ inline bool shouldRespondToDirectPathPush(const uint64_t now) { if ((now - _lastDirectPathPushReceive) <= ZT_PUSH_DIRECT_PATHS_CUTOFF_TIME) ++_directPathPushCutoffCount; else _directPathPushCutoffCount = 0; _lastDirectPathPushReceive = now; return (_directPathPushCutoffCount < ZT_PUSH_DIRECT_PATHS_CUTOFF_LIMIT); } /** * Find a common set of addresses by which two peers can link, if any * * @param a Peer A * @param b Peer B * @param now Current time * @return Pair: B's address (to send to A), A's address (to send to B) */ static inline std::pair findCommonGround(const Peer &a,const Peer &b,uint64_t now) { std::pair v4,v6; b.getBestActiveAddresses(now,v4.first,v6.first); a.getBestActiveAddresses(now,v4.second,v6.second); if ((v6.first)&&(v6.second)) // prefer IPv6 if both have it since NAT-t is (almost) unnecessary return v6; else if ((v4.first)&&(v4.second)) return v4; else return std::pair(); } private: void _doDeadPathDetection(Path &p,const uint64_t now); Path *_getBestPath(const uint64_t now); Path *_getBestPath(const uint64_t now,int inetAddressFamily); unsigned char _key[ZT_PEER_SECRET_KEY_LENGTH]; const RuntimeEnvironment *RR; uint64_t _lastUsed; uint64_t _lastReceive; // direct or indirect uint64_t _lastUnicastFrame; uint64_t _lastMulticastFrame; uint64_t _lastAnnouncedTo; uint64_t _lastDirectPathPushSent; uint64_t _lastDirectPathPushReceive; uint64_t _lastPathSort; uint16_t _vProto; uint16_t _vMajor; uint16_t _vMinor; uint16_t _vRevision; Identity _id; Path _paths[ZT_MAX_PEER_NETWORK_PATHS]; unsigned int _numPaths; unsigned int _latency; unsigned int _directPathPushCutoffCount; AtomicCounter __refCount; }; } // namespace ZeroTier // Add a swap() for shared ptr's to peers to speed up peer sorts namespace std { template<> inline void swap(ZeroTier::SharedPtr &a,ZeroTier::SharedPtr &b) { a.swap(b); } } #endif