// Copyright (c) 2009-2010 Satoshi Nakamoto // Copyright (c) 2009-2015 The Bitcoin Core developers // Distributed under the MIT software license, see the accompanying // file COPYING or http://www.opensource.org/licenses/mit-license.php. #ifndef BITCOIN_NET_H #define BITCOIN_NET_H #include "amount.h" #include "bloom.h" #include "compat.h" #include "limitedmap.h" #include "netbase.h" #include "protocol.h" #include "random.h" #include "streams.h" #include "sync.h" #include "uint256.h" #include #include #include #ifndef WIN32 #include #endif #include #include #include class CAddrMan; class CScheduler; class CNode; namespace boost { class thread_group; } // namespace boost /** Time between pings automatically sent out for latency probing and keepalive (in seconds). */ static const int PING_INTERVAL = 2 * 60; /** Time after which to disconnect, after waiting for a ping response (or inactivity). */ static const int TIMEOUT_INTERVAL = 20 * 60; /** The maximum number of entries in an 'inv' protocol message */ static const unsigned int MAX_INV_SZ = 50000; /** The maximum number of new addresses to accumulate before announcing. */ static const unsigned int MAX_ADDR_TO_SEND = 1000; /** Maximum length of incoming protocol messages (no message over 2 MiB is currently acceptable). */ static const unsigned int MAX_PROTOCOL_MESSAGE_LENGTH = 2 * 1024 * 1024; /** Maximum length of strSubVer in `version` message */ static const unsigned int MAX_SUBVERSION_LENGTH = 256; /** -listen default */ static const bool DEFAULT_LISTEN = true; /** -upnp default */ #ifdef USE_UPNP static const bool DEFAULT_UPNP = USE_UPNP; #else static const bool DEFAULT_UPNP = false; #endif /** The maximum number of entries in mapAskFor */ static const size_t MAPASKFOR_MAX_SZ = MAX_INV_SZ; /** The maximum number of entries in setAskFor (larger due to getdata latency)*/ static const size_t SETASKFOR_MAX_SZ = 2 * MAX_INV_SZ; /** The maximum number of peer connections to maintain. */ static const unsigned int DEFAULT_MAX_PEER_CONNECTIONS = 125; /** The default for -maxuploadtarget. 0 = Unlimited */ static const uint64_t DEFAULT_MAX_UPLOAD_TARGET = 0; /** Default for blocks only*/ static const bool DEFAULT_BLOCKSONLY = false; static const bool DEFAULT_FORCEDNSSEED = false; static const size_t DEFAULT_MAXRECEIVEBUFFER = 5 * 1000; static const size_t DEFAULT_MAXSENDBUFFER = 1 * 1000; static const ServiceFlags REQUIRED_SERVICES = NODE_NETWORK; // NOTE: When adjusting this, update rpcnet:setban's help ("24h") static const unsigned int DEFAULT_MISBEHAVING_BANTIME = 60 * 60 * 24; // Default 24-hour ban unsigned int ReceiveFloodSize(); unsigned int SendBufferSize(); void AddOneShot(const std::string& strDest); void AddressCurrentlyConnected(const CService& addr); CNode* FindNode(const CNetAddr& ip); CNode* FindNode(const CSubNet& subNet); CNode* FindNode(const std::string& addrName); CNode* FindNode(const CService& ip); bool OpenNetworkConnection(const CAddress& addrConnect, bool fCountFailure, CSemaphoreGrant *grantOutbound = NULL, const char *strDest = NULL, bool fOneShot = false); void MapPort(bool fUseUPnP); unsigned short GetListenPort(); bool BindListenPort(const CService &bindAddr, std::string& strError, bool fWhitelisted = false); void StartNode(boost::thread_group& threadGroup, CScheduler& scheduler); bool StopNode(); void SocketSendData(CNode *pnode); typedef int NodeId; struct CombinerAll { typedef bool result_type; template bool operator()(I first, I last) const { while (first != last) { if (!(*first)) return false; ++first; } return true; } }; // Signals for message handling struct CNodeSignals { boost::signals2::signal GetHeight; boost::signals2::signal ProcessMessages; boost::signals2::signal SendMessages; boost::signals2::signal InitializeNode; boost::signals2::signal FinalizeNode; }; CNodeSignals& GetNodeSignals(); enum { LOCAL_NONE, // unknown LOCAL_IF, // address a local interface listens on LOCAL_BIND, // address explicit bound to LOCAL_UPNP, // address reported by UPnP LOCAL_MANUAL, // address explicitly specified (-externalip=) LOCAL_MAX }; bool IsPeerAddrLocalGood(CNode *pnode); void AdvertiseLocal(CNode *pnode); void SetLimited(enum Network net, bool fLimited = true); bool IsLimited(enum Network net); bool IsLimited(const CNetAddr& addr); bool AddLocal(const CService& addr, int nScore = LOCAL_NONE); bool AddLocal(const CNetAddr& addr, int nScore = LOCAL_NONE); bool RemoveLocal(const CService& addr); bool SeenLocal(const CService& addr); bool IsLocal(const CService& addr); bool GetLocal(CService &addr, const CNetAddr *paddrPeer = NULL); bool IsReachable(enum Network net); bool IsReachable(const CNetAddr &addr); CAddress GetLocalAddress(const CNetAddr *paddrPeer = NULL); extern bool fDiscover; extern bool fListen; extern ServiceFlags nLocalServices; extern bool fRelayTxes; extern uint64_t nLocalHostNonce; extern CAddrMan addrman; /** Maximum number of connections to simultaneously allow (aka connection slots) */ extern int nMaxConnections; extern std::vector vNodes; extern CCriticalSection cs_vNodes; extern limitedmap mapAlreadyAskedFor; extern std::vector vAddedNodes; extern CCriticalSection cs_vAddedNodes; extern NodeId nLastNodeId; extern CCriticalSection cs_nLastNodeId; /** Subversion as sent to the P2P network in `version` messages */ extern std::string strSubVersion; struct LocalServiceInfo { int nScore; int nPort; }; extern CCriticalSection cs_mapLocalHost; extern std::map mapLocalHost; typedef std::map mapMsgCmdSize; //command, total bytes class CNodeStats { public: NodeId nodeid; ServiceFlags nServices; bool fRelayTxes; int64_t nLastSend; int64_t nLastRecv; int64_t nTimeConnected; int64_t nTimeOffset; std::string addrName; int nVersion; std::string cleanSubVer; bool fInbound; int nStartingHeight; uint64_t nSendBytes; mapMsgCmdSize mapSendBytesPerMsgCmd; uint64_t nRecvBytes; mapMsgCmdSize mapRecvBytesPerMsgCmd; bool fWhitelisted; double dPingTime; double dPingWait; double dPingMin; std::string addrLocal; }; class CNetMessage { public: bool in_data; // parsing header (false) or data (true) CDataStream hdrbuf; // partially received header CMessageHeader hdr; // complete header unsigned int nHdrPos; CDataStream vRecv; // received message data unsigned int nDataPos; int64_t nTime; // time (in microseconds) of message receipt. CNetMessage(const CMessageHeader::MessageStartChars& pchMessageStartIn, int nTypeIn, int nVersionIn) : hdrbuf(nTypeIn, nVersionIn), hdr(pchMessageStartIn), vRecv(nTypeIn, nVersionIn) { hdrbuf.resize(24); in_data = false; nHdrPos = 0; nDataPos = 0; nTime = 0; } bool complete() const { if (!in_data) return false; return (hdr.nMessageSize == nDataPos); } void SetVersion(int nVersionIn) { hdrbuf.SetVersion(nVersionIn); vRecv.SetVersion(nVersionIn); } int readHeader(const char *pch, unsigned int nBytes); int readData(const char *pch, unsigned int nBytes); }; typedef enum BanReason { BanReasonUnknown = 0, BanReasonNodeMisbehaving = 1, BanReasonManuallyAdded = 2 } BanReason; class CBanEntry { public: static const int CURRENT_VERSION=1; int nVersion; int64_t nCreateTime; int64_t nBanUntil; uint8_t banReason; CBanEntry() { SetNull(); } CBanEntry(int64_t nCreateTimeIn) { SetNull(); nCreateTime = nCreateTimeIn; } ADD_SERIALIZE_METHODS; template inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) { READWRITE(this->nVersion); nVersion = this->nVersion; READWRITE(nCreateTime); READWRITE(nBanUntil); READWRITE(banReason); } void SetNull() { nVersion = CBanEntry::CURRENT_VERSION; nCreateTime = 0; nBanUntil = 0; banReason = BanReasonUnknown; } std::string banReasonToString() { switch (banReason) { case BanReasonNodeMisbehaving: return "node misbehaving"; case BanReasonManuallyAdded: return "manually added"; default: return "unknown"; } } }; typedef std::map banmap_t; /** Information about a peer */ class CNode { public: // socket ServiceFlags nServices; ServiceFlags nServicesExpected; SOCKET hSocket; CDataStream ssSend; size_t nSendSize; // total size of all vSendMsg entries size_t nSendOffset; // offset inside the first vSendMsg already sent uint64_t nSendBytes; std::deque vSendMsg; CCriticalSection cs_vSend; std::deque vRecvGetData; std::deque vRecvMsg; CCriticalSection cs_vRecvMsg; uint64_t nRecvBytes; int nRecvVersion; int64_t nLastSend; int64_t nLastRecv; int64_t nTimeConnected; int64_t nTimeOffset; const CAddress addr; std::string addrName; CService addrLocal; int nVersion; // strSubVer is whatever byte array we read from the wire. However, this field is intended // to be printed out, displayed to humans in various forms and so on. So we sanitize it and // store the sanitized version in cleanSubVer. The original should be used when dealing with // the network or wire types and the cleaned string used when displayed or logged. std::string strSubVer, cleanSubVer; bool fWhitelisted; // This peer can bypass DoS banning. bool fOneShot; bool fClient; bool fInbound; bool fNetworkNode; bool fSuccessfullyConnected; bool fDisconnect; // We use fRelayTxes for two purposes - // a) it allows us to not relay tx invs before receiving the peer's version message // b) the peer may tell us in its version message that we should not relay tx invs // unless it loads a bloom filter. bool fRelayTxes; //protected by cs_filter bool fSentAddr; CSemaphoreGrant grantOutbound; CCriticalSection cs_filter; CBloomFilter* pfilter; int nRefCount; NodeId id; const uint64_t nKeyedNetGroup; protected: // Denial-of-service detection/prevention // Key is IP address, value is banned-until-time static banmap_t setBanned; static CCriticalSection cs_setBanned; static bool setBannedIsDirty; // Whitelisted ranges. Any node connecting from these is automatically // whitelisted (as well as those connecting to whitelisted binds). static std::vector vWhitelistedRange; static CCriticalSection cs_vWhitelistedRange; mapMsgCmdSize mapSendBytesPerMsgCmd; mapMsgCmdSize mapRecvBytesPerMsgCmd; // Basic fuzz-testing void Fuzz(int nChance); // modifies ssSend public: uint256 hashContinue; int nStartingHeight; // flood relay std::vector vAddrToSend; CRollingBloomFilter addrKnown; bool fGetAddr; std::set setKnown; int64_t nNextAddrSend; int64_t nNextLocalAddrSend; // inventory based relay CRollingBloomFilter filterInventoryKnown; // Set of transaction ids we still have to announce. // They are sorted by the mempool before relay, so the order is not important. std::set setInventoryTxToSend; // List of block ids we still have announce. // There is no final sorting before sending, as they are always sent immediately // and in the order requested. std::vector vInventoryBlockToSend; CCriticalSection cs_inventory; std::set setAskFor; std::multimap mapAskFor; int64_t nNextInvSend; // Used for headers announcements - unfiltered blocks to relay // Also protected by cs_inventory std::vector vBlockHashesToAnnounce; // Used for BIP35 mempool sending, also protected by cs_inventory bool fSendMempool; // Last time a "MEMPOOL" request was serviced. std::atomic timeLastMempoolReq; // Ping time measurement: // The pong reply we're expecting, or 0 if no pong expected. uint64_t nPingNonceSent; // Time (in usec) the last ping was sent, or 0 if no ping was ever sent. int64_t nPingUsecStart; // Last measured round-trip time. int64_t nPingUsecTime; // Best measured round-trip time. int64_t nMinPingUsecTime; // Whether a ping is requested. bool fPingQueued; // Minimum fee rate with which to filter inv's to this node CAmount minFeeFilter; CCriticalSection cs_feeFilter; CAmount lastSentFeeFilter; int64_t nextSendTimeFeeFilter; CNode(SOCKET hSocketIn, const CAddress &addrIn, const std::string &addrNameIn = "", bool fInboundIn = false); ~CNode(); private: // Network usage totals static CCriticalSection cs_totalBytesRecv; static CCriticalSection cs_totalBytesSent; static uint64_t nTotalBytesRecv; static uint64_t nTotalBytesSent; // outbound limit & stats static uint64_t nMaxOutboundTotalBytesSentInCycle; static uint64_t nMaxOutboundCycleStartTime; static uint64_t nMaxOutboundLimit; static uint64_t nMaxOutboundTimeframe; CNode(const CNode&); void operator=(const CNode&); static uint64_t CalculateKeyedNetGroup(const CAddress& ad); public: NodeId GetId() const { return id; } int GetRefCount() { assert(nRefCount >= 0); return nRefCount; } // requires LOCK(cs_vRecvMsg) unsigned int GetTotalRecvSize() { unsigned int total = 0; BOOST_FOREACH(const CNetMessage &msg, vRecvMsg) total += msg.vRecv.size() + 24; return total; } // requires LOCK(cs_vRecvMsg) bool ReceiveMsgBytes(const char *pch, unsigned int nBytes); // requires LOCK(cs_vRecvMsg) void SetRecvVersion(int nVersionIn) { nRecvVersion = nVersionIn; BOOST_FOREACH(CNetMessage &msg, vRecvMsg) msg.SetVersion(nVersionIn); } CNode* AddRef() { nRefCount++; return this; } void Release() { nRefCount--; } void AddAddressKnown(const CAddress& addr) { addrKnown.insert(addr.GetKey()); } void PushAddress(const CAddress& addr) { // Known checking here is only to save space from duplicates. // SendMessages will filter it again for knowns that were added // after addresses were pushed. if (addr.IsValid() && !addrKnown.contains(addr.GetKey())) { if (vAddrToSend.size() >= MAX_ADDR_TO_SEND) { vAddrToSend[insecure_rand() % vAddrToSend.size()] = addr; } else { vAddrToSend.push_back(addr); } } } void AddInventoryKnown(const CInv& inv) { { LOCK(cs_inventory); filterInventoryKnown.insert(inv.hash); } } void PushInventory(const CInv& inv) { LOCK(cs_inventory); if (inv.type == MSG_TX) { if (!filterInventoryKnown.contains(inv.hash)) { setInventoryTxToSend.insert(inv.hash); } } else if (inv.type == MSG_BLOCK) { vInventoryBlockToSend.push_back(inv.hash); } } void PushBlockHash(const uint256 &hash) { LOCK(cs_inventory); vBlockHashesToAnnounce.push_back(hash); } void AskFor(const CInv& inv); // TODO: Document the postcondition of this function. Is cs_vSend locked? void BeginMessage(const char* pszCommand) EXCLUSIVE_LOCK_FUNCTION(cs_vSend); // TODO: Document the precondition of this function. Is cs_vSend locked? void AbortMessage() UNLOCK_FUNCTION(cs_vSend); // TODO: Document the precondition of this function. Is cs_vSend locked? void EndMessage(const char* pszCommand) UNLOCK_FUNCTION(cs_vSend); void PushVersion(); void PushMessage(const char* pszCommand) { try { BeginMessage(pszCommand); EndMessage(pszCommand); } catch (...) { AbortMessage(); throw; } } template void PushMessage(const char* pszCommand, const T1& a1) { try { BeginMessage(pszCommand); ssSend << a1; EndMessage(pszCommand); } catch (...) { AbortMessage(); throw; } } template void PushMessage(const char* pszCommand, const T1& a1, const T2& a2) { try { BeginMessage(pszCommand); ssSend << a1 << a2; EndMessage(pszCommand); } catch (...) { AbortMessage(); throw; } } template void PushMessage(const char* pszCommand, const T1& a1, const T2& a2, const T3& a3) { try { BeginMessage(pszCommand); ssSend << a1 << a2 << a3; EndMessage(pszCommand); } catch (...) { AbortMessage(); throw; } } template void PushMessage(const char* pszCommand, const T1& a1, const T2& a2, const T3& a3, const T4& a4) { try { BeginMessage(pszCommand); ssSend << a1 << a2 << a3 << a4; EndMessage(pszCommand); } catch (...) { AbortMessage(); throw; } } template void PushMessage(const char* pszCommand, const T1& a1, const T2& a2, const T3& a3, const T4& a4, const T5& a5) { try { BeginMessage(pszCommand); ssSend << a1 << a2 << a3 << a4 << a5; EndMessage(pszCommand); } catch (...) { AbortMessage(); throw; } } template void PushMessage(const char* pszCommand, const T1& a1, const T2& a2, const T3& a3, const T4& a4, const T5& a5, const T6& a6) { try { BeginMessage(pszCommand); ssSend << a1 << a2 << a3 << a4 << a5 << a6; EndMessage(pszCommand); } catch (...) { AbortMessage(); throw; } } template void PushMessage(const char* pszCommand, const T1& a1, const T2& a2, const T3& a3, const T4& a4, const T5& a5, const T6& a6, const T7& a7) { try { BeginMessage(pszCommand); ssSend << a1 << a2 << a3 << a4 << a5 << a6 << a7; EndMessage(pszCommand); } catch (...) { AbortMessage(); throw; } } template void PushMessage(const char* pszCommand, const T1& a1, const T2& a2, const T3& a3, const T4& a4, const T5& a5, const T6& a6, const T7& a7, const T8& a8) { try { BeginMessage(pszCommand); ssSend << a1 << a2 << a3 << a4 << a5 << a6 << a7 << a8; EndMessage(pszCommand); } catch (...) { AbortMessage(); throw; } } template void PushMessage(const char* pszCommand, const T1& a1, const T2& a2, const T3& a3, const T4& a4, const T5& a5, const T6& a6, const T7& a7, const T8& a8, const T9& a9) { try { BeginMessage(pszCommand); ssSend << a1 << a2 << a3 << a4 << a5 << a6 << a7 << a8 << a9; EndMessage(pszCommand); } catch (...) { AbortMessage(); throw; } } void CloseSocketDisconnect(); // Denial-of-service detection/prevention // The idea is to detect peers that are behaving // badly and disconnect/ban them, but do it in a // one-coding-mistake-won't-shatter-the-entire-network // way. // IMPORTANT: There should be nothing I can give a // node that it will forward on that will make that // node's peers drop it. If there is, an attacker // can isolate a node and/or try to split the network. // Dropping a node for sending stuff that is invalid // now but might be valid in a later version is also // dangerous, because it can cause a network split // between nodes running old code and nodes running // new code. static void ClearBanned(); // needed for unit testing static bool IsBanned(CNetAddr ip); static bool IsBanned(CSubNet subnet); static void Ban(const CNetAddr &ip, const BanReason &banReason, int64_t bantimeoffset = 0, bool sinceUnixEpoch = false); static void Ban(const CSubNet &subNet, const BanReason &banReason, int64_t bantimeoffset = 0, bool sinceUnixEpoch = false); static bool Unban(const CNetAddr &ip); static bool Unban(const CSubNet &ip); static void GetBanned(banmap_t &banmap); static void SetBanned(const banmap_t &banmap); //!check is the banlist has unwritten changes static bool BannedSetIsDirty(); //!set the "dirty" flag for the banlist static void SetBannedSetDirty(bool dirty=true); //!clean unused entries (if bantime has expired) static void SweepBanned(); void copyStats(CNodeStats &stats); static bool IsWhitelistedRange(const CNetAddr &ip); static void AddWhitelistedRange(const CSubNet &subnet); // Network stats static void RecordBytesRecv(uint64_t bytes); static void RecordBytesSent(uint64_t bytes); static uint64_t GetTotalBytesRecv(); static uint64_t GetTotalBytesSent(); //!set the max outbound target in bytes static void SetMaxOutboundTarget(uint64_t limit); static uint64_t GetMaxOutboundTarget(); //!set the timeframe for the max outbound target static void SetMaxOutboundTimeframe(uint64_t timeframe); static uint64_t GetMaxOutboundTimeframe(); //!check if the outbound target is reached // if param historicalBlockServingLimit is set true, the function will // response true if the limit for serving historical blocks has been reached static bool OutboundTargetReached(bool historicalBlockServingLimit); //!response the bytes left in the current max outbound cycle // in case of no limit, it will always response 0 static uint64_t GetOutboundTargetBytesLeft(); //!response the time in second left in the current max outbound cycle // in case of no limit, it will always response 0 static uint64_t GetMaxOutboundTimeLeftInCycle(); }; class CTransaction; void RelayTransaction(const CTransaction& tx); /** Access to the (IP) address database (peers.dat) */ class CAddrDB { private: boost::filesystem::path pathAddr; public: CAddrDB(); bool Write(const CAddrMan& addr); bool Read(CAddrMan& addr); bool Read(CAddrMan& addr, CDataStream& ssPeers); }; /** Access to the banlist database (banlist.dat) */ class CBanDB { private: boost::filesystem::path pathBanlist; public: CBanDB(); bool Write(const banmap_t& banSet); bool Read(banmap_t& banSet); }; /** Return a timestamp in the future (in microseconds) for exponentially distributed events. */ int64_t PoissonNextSend(int64_t nNow, int average_interval_seconds); struct AddedNodeInfo { std::string strAddedNode; CService resolvedAddress; bool fConnected; bool fInbound; }; std::vector GetAddedNodeInfo(); #endif // BITCOIN_NET_H