diff --git a/src/net.h b/src/net.h index 7d458a03e..2a97decc5 100644 --- a/src/net.h +++ b/src/net.h @@ -1,1420 +1,1398 @@ // Copyright (c) 2009-2010 Satoshi Nakamoto // Copyright (c) 2009-2019 The Bitcoin Core developers // Copyright (c) 2017-2019 The Bitcoin 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include // For cs_main #include #include #include #include #include #include #include #include #ifndef WIN32 #include #endif class BanMan; class Config; class CNode; class CScheduler; struct bilingual_str; /** Default for -whitelistrelay. */ static const bool DEFAULT_WHITELISTRELAY = true; /** Default for -whitelistforcerelay. */ static const bool DEFAULT_WHITELISTFORCERELAY = false; /** * Time after which to disconnect, after waiting for a ping response (or * inactivity). */ static const int TIMEOUT_INTERVAL = 20 * 60; /** Run the feeler connection loop once every 2 minutes. **/ static constexpr auto FEELER_INTERVAL = 2min; /** Run the extra block-relay-only connection loop once every 5 minutes. **/ static constexpr auto EXTRA_BLOCK_RELAY_ONLY_PEER_INTERVAL = 5min; /** Maximum length of the user agent string in `version` message */ static const unsigned int MAX_SUBVERSION_LENGTH = 256; /** * Maximum number of automatic outgoing nodes over which we'll relay everything * (blocks, tx, addrs, etc) */ static const int MAX_OUTBOUND_FULL_RELAY_CONNECTIONS = 8; /** Maximum number of addnode outgoing nodes */ static const int MAX_ADDNODE_CONNECTIONS = 8; /** Maximum number of block-relay-only outgoing connections */ static const int MAX_BLOCK_RELAY_ONLY_CONNECTIONS = 2; /** Maximum number of feeler connections */ static const int MAX_FEELER_CONNECTIONS = 1; /** -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 peer connections to maintain. * This quantity might not be reachable on some systems, especially on platforms * that do not provide a working poll() interface. */ static const unsigned int DEFAULT_MAX_PEER_CONNECTIONS = 4096; /** The default for -maxuploadtarget. 0 = Unlimited */ static constexpr uint64_t DEFAULT_MAX_UPLOAD_TARGET = 0; /** Default for blocks only*/ static const bool DEFAULT_BLOCKSONLY = false; /** -peertimeout default */ static const int64_t DEFAULT_PEER_CONNECT_TIMEOUT = 60; static const bool DEFAULT_FORCEDNSSEED = false; static const bool DEFAULT_DNSSEED = true; static const bool DEFAULT_FIXEDSEEDS = true; static const size_t DEFAULT_MAXRECEIVEBUFFER = 5 * 1000; static const size_t DEFAULT_MAXSENDBUFFER = 1 * 1000; /** Refresh period for the avalanche statistics computation */ static constexpr std::chrono::minutes AVALANCHE_STATISTICS_REFRESH_PERIOD{10}; /** Time constant for the avalanche statistics computation */ static constexpr std::chrono::minutes AVALANCHE_STATISTICS_TIME_CONSTANT{10}; /** * Pre-computed decay factor for the avalanche statistics computation. * There is currently no constexpr variant of std::exp, so use a const. */ static const double AVALANCHE_STATISTICS_DECAY_FACTOR = 1. - std::exp(-1. * AVALANCHE_STATISTICS_REFRESH_PERIOD.count() / AVALANCHE_STATISTICS_TIME_CONSTANT.count()); struct AddedNodeInfo { std::string strAddedNode; CService resolvedAddress; bool fConnected; bool fInbound; }; struct CNodeStats; class CClientUIInterface; struct CSerializedNetMsg { CSerializedNetMsg() = default; CSerializedNetMsg(CSerializedNetMsg &&) = default; CSerializedNetMsg &operator=(CSerializedNetMsg &&) = default; // No copying, only moves. CSerializedNetMsg(const CSerializedNetMsg &msg) = delete; CSerializedNetMsg &operator=(const CSerializedNetMsg &) = delete; std::vector data; std::string m_type; }; const std::vector CONNECTION_TYPE_DOC{ "outbound-full-relay (default automatic connections)", "block-relay-only (does not relay transactions or addresses)", "inbound (initiated by the peer)", "manual (added via addnode RPC or -addnode/-connect configuration options)", "addr-fetch (short-lived automatic connection for soliciting addresses)", "feeler (short-lived automatic connection for testing addresses)"}; /** * Different types of connections to a peer. This enum encapsulates the * information we have available at the time of opening or accepting the * connection. Aside from INBOUND, all types are initiated by us. */ enum class ConnectionType { /** * Inbound connections are those initiated by a peer. This is the only * property we know at the time of connection, until P2P messages are * exchanged. */ INBOUND, /** * These are the default connections that we use to connect with the * network. There is no restriction on what is relayed- by default we relay * blocks, addresses & transactions. We automatically attempt to open * MAX_OUTBOUND_FULL_RELAY_CONNECTIONS using addresses from our AddrMan. */ OUTBOUND_FULL_RELAY, /** * We open manual connections to addresses that users explicitly inputted * via the addnode RPC, or the -connect command line argument. Even if a * manual connection is misbehaving, we do not automatically disconnect or * add it to our discouragement filter. */ MANUAL, /** * Feeler connections are short-lived connections made to check that a node * is alive. They can be useful for: * - test-before-evict: if one of the peers is considered for eviction from * our AddrMan because another peer is mapped to the same slot in the * tried table, evict only if this longer-known peer is offline. * - move node addresses from New to Tried table, so that we have more * connectable addresses in our AddrMan. * Note that in the literature ("Eclipse Attacks on Bitcoin’s Peer-to-Peer * Network") only the latter feature is referred to as "feeler connections", * although in our codebase feeler connections encompass test-before-evict * as well. * We make these connections approximately every FEELER_INTERVAL: * first we resolve previously found collisions if they exist * (test-before-evict), otherwise connect to a node from the new table. */ FEELER, /** * We use block-relay-only connections to help prevent against partition * attacks. By not relaying transactions or addresses, these connections * are harder to detect by a third party, thus helping obfuscate the * network topology. We automatically attempt to open * MAX_BLOCK_RELAY_ONLY_ANCHORS using addresses from our anchors.dat. Then * addresses from our AddrMan if MAX_BLOCK_RELAY_ONLY_CONNECTIONS * isn't reached yet. */ BLOCK_RELAY, /** * AddrFetch connections are short lived connections used to solicit * addresses from peers. These are initiated to addresses submitted via the * -seednode command line argument, or under certain conditions when the * AddrMan is empty. */ ADDR_FETCH, }; void Discover(); void StartMapPort(); void InterruptMapPort(); void StopMapPort(); uint16_t GetListenPort(); enum { // unknown LOCAL_NONE, // address a local interface listens on LOCAL_IF, // address explicit bound to LOCAL_BIND, // address reported by UPnP LOCAL_UPNP, // address explicitly specified (-externalip=) LOCAL_MANUAL, LOCAL_MAX }; bool IsPeerAddrLocalGood(CNode *pnode); /** Returns a local address that we should advertise to this peer */ std::optional GetLocalAddrForPeer(CNode *pnode); /** * Mark a network as reachable or unreachable (no automatic connects to it) * @note Networks are reachable by default */ void SetReachable(enum Network net, bool reachable); /** @returns true if the network is reachable, false otherwise */ bool IsReachable(enum Network net); /** @returns true if the address is in a reachable network, false otherwise */ bool IsReachable(const CNetAddr &addr); bool AddLocal(const CService &addr, int nScore = LOCAL_NONE); bool AddLocal(const CNetAddr &addr, int nScore = LOCAL_NONE); void RemoveLocal(const CService &addr); bool SeenLocal(const CService &addr); bool IsLocal(const CService &addr); bool GetLocal(CService &addr, const CNetAddr *paddrPeer = nullptr); CAddress GetLocalAddress(const CNetAddr *paddrPeer, ServiceFlags nLocalServices); extern bool fDiscover; extern bool fListen; struct LocalServiceInfo { int nScore; int nPort; }; extern RecursiveMutex cs_mapLocalHost; extern std::map mapLocalHost GUARDED_BY(cs_mapLocalHost); extern const std::string NET_MESSAGE_COMMAND_OTHER; // Command, total bytes typedef std::map mapMsgCmdSize; /** * POD that contains various stats about a node. * Usually constructed from CConman::GetNodeStats. Stats are filled from the * node using CNode::copyStats. */ struct CNodeStats { NodeId nodeid; ServiceFlags nServices; bool fRelayTxes; int64_t nLastSend; int64_t nLastRecv; int64_t nLastTXTime; int64_t nLastProofTime; int64_t nLastBlockTime; int64_t nTimeConnected; int64_t nTimeOffset; std::string addrName; int nVersion; std::string cleanSubVer; bool fInbound; bool m_manual_connection; int m_starting_height; uint64_t nSendBytes; mapMsgCmdSize mapSendBytesPerMsgCmd; uint64_t nRecvBytes; mapMsgCmdSize mapRecvBytesPerMsgCmd; NetPermissionFlags m_permissionFlags; bool m_legacyWhitelisted; std::chrono::microseconds m_last_ping_time; std::chrono::microseconds m_min_ping_time; Amount minFeeFilter; // Our address, as reported by the peer std::string addrLocal; // Address of this peer CAddress addr; // Bind address of our side of the connection CAddress addrBind; // Name of the network the peer connected through std::string m_network; uint32_t m_mapped_as; std::string m_conn_type_string; }; /** * Transport protocol agnostic message container. * Ideally it should only contain receive time, payload, * command and size. */ class CNetMessage { public: //! received message data CDataStream m_recv; //! time of message receipt std::chrono::microseconds m_time{0}; bool m_valid_netmagic = false; bool m_valid_header = false; bool m_valid_checksum = false; //! size of the payload uint32_t m_message_size{0}; //! used wire size of the message (including header/checksum) uint32_t m_raw_message_size{0}; std::string m_command; CNetMessage(CDataStream &&recv_in) : m_recv(std::move(recv_in)) {} void SetVersion(int nVersionIn) { m_recv.SetVersion(nVersionIn); } }; /** * The TransportDeserializer takes care of holding and deserializing the * network receive buffer. It can deserialize the network buffer into a * transport protocol agnostic CNetMessage (command & payload) */ class TransportDeserializer { public: // returns true if the current deserialization is complete virtual bool Complete() const = 0; // set the serialization context version virtual void SetVersion(int version) = 0; /** read and deserialize data, advances msg_bytes data pointer */ virtual int Read(const Config &config, Span &msg_bytes) = 0; // decomposes a message from the context virtual CNetMessage GetMessage(const Config &config, std::chrono::microseconds time) = 0; virtual ~TransportDeserializer() {} }; class V1TransportDeserializer final : public TransportDeserializer { private: mutable CHash256 hasher; mutable uint256 data_hash; // Parsing header (false) or data (true) bool in_data; // Partially received header. CDataStream hdrbuf; // Complete header. CMessageHeader hdr; // Received message data. CDataStream vRecv; uint32_t nHdrPos; uint32_t nDataPos; const uint256 &GetMessageHash() const; int readHeader(const Config &config, Span msg_bytes); int readData(Span msg_bytes); void Reset() { vRecv.clear(); hdrbuf.clear(); hdrbuf.resize(24); in_data = false; nHdrPos = 0; nDataPos = 0; data_hash.SetNull(); hasher.Reset(); } public: V1TransportDeserializer( const CMessageHeader::MessageMagic &pchMessageStartIn, int nTypeIn, int nVersionIn) : hdrbuf(nTypeIn, nVersionIn), hdr(pchMessageStartIn), vRecv(nTypeIn, nVersionIn) { Reset(); } bool Complete() const override { if (!in_data) { return false; } return (hdr.nMessageSize == nDataPos); } void SetVersion(int nVersionIn) override { hdrbuf.SetVersion(nVersionIn); vRecv.SetVersion(nVersionIn); } int Read(const Config &config, Span &msg_bytes) override { int ret = in_data ? readData(msg_bytes) : readHeader(config, msg_bytes); if (ret < 0) { Reset(); } else { msg_bytes = msg_bytes.subspan(ret); } return ret; } CNetMessage GetMessage(const Config &config, std::chrono::microseconds time) override; }; /** * The TransportSerializer prepares messages for the network transport */ class TransportSerializer { public: // prepare message for transport (header construction, error-correction // computation, payload encryption, etc.) virtual void prepareForTransport(const Config &config, CSerializedNetMsg &msg, std::vector &header) = 0; virtual ~TransportSerializer() {} }; class V1TransportSerializer : public TransportSerializer { public: void prepareForTransport(const Config &config, CSerializedNetMsg &msg, std::vector &header) override; }; /** Information about a peer */ class CNode { friend class CConnman; friend struct ConnmanTestMsg; public: std::unique_ptr m_deserializer; std::unique_ptr m_serializer; // socket std::atomic nServices{NODE_NONE}; SOCKET hSocket GUARDED_BY(cs_hSocket); // Total size of all vSendMsg entries. size_t nSendSize{0}; // Offset inside the first vSendMsg already sent. size_t nSendOffset{0}; uint64_t nSendBytes GUARDED_BY(cs_vSend){0}; std::deque> vSendMsg GUARDED_BY(cs_vSend); Mutex cs_vSend; Mutex cs_hSocket; Mutex cs_vRecv; RecursiveMutex cs_vProcessMsg; std::list vProcessMsg GUARDED_BY(cs_vProcessMsg); size_t nProcessQueueSize{0}; RecursiveMutex cs_sendProcessing; uint64_t nRecvBytes GUARDED_BY(cs_vRecv){0}; std::atomic nLastSend{0}; std::atomic nLastRecv{0}; const int64_t nTimeConnected; std::atomic nTimeOffset{0}; // Address of this peer const CAddress addr; // Bind address of our side of the connection const CAddress addrBind; std::atomic nVersion{0}; // The nonce provided by the remote host. uint64_t nRemoteHostNonce{0}; // The extra entropy provided by the remote host. uint64_t nRemoteExtraEntropy{0}; /** * cleanSubVer is a sanitized string of the user agent byte array we read * from the wire. This cleaned string can safely be logged or displayed. */ RecursiveMutex cs_SubVer; std::string cleanSubVer GUARDED_BY(cs_SubVer){}; // This peer is preferred for eviction. bool m_prefer_evict{false}; bool HasPermission(NetPermissionFlags permission) const { return NetPermissions::HasFlag(m_permissionFlags, permission); } // This boolean is unusued in actual processing, only present for backward // compatibility at RPC/QT level bool m_legacyWhitelisted{false}; // set by version message bool fClient{false}; // after BIP159, set by version message bool m_limited_node{false}; std::atomic_bool fSuccessfullyConnected{false}; // Setting fDisconnect to true will cause the node to be disconnected the // next time DisconnectNodes() runs std::atomic_bool fDisconnect{false}; CSemaphoreGrant grantOutbound; std::atomic nRefCount{0}; const uint64_t nKeyedNetGroup; std::atomic_bool fPauseRecv{false}; std::atomic_bool fPauseSend{false}; bool IsOutboundOrBlockRelayConn() const { switch (m_conn_type) { case ConnectionType::OUTBOUND_FULL_RELAY: case ConnectionType::BLOCK_RELAY: return true; case ConnectionType::INBOUND: case ConnectionType::MANUAL: case ConnectionType::ADDR_FETCH: case ConnectionType::FEELER: return false; } // no default case, so the compiler can warn about missing cases assert(false); } bool IsFullOutboundConn() const { return m_conn_type == ConnectionType::OUTBOUND_FULL_RELAY; } bool IsManualConn() const { return m_conn_type == ConnectionType::MANUAL; } bool IsBlockOnlyConn() const { return m_conn_type == ConnectionType::BLOCK_RELAY; } bool IsFeelerConn() const { return m_conn_type == ConnectionType::FEELER; } bool IsAddrFetchConn() const { return m_conn_type == ConnectionType::ADDR_FETCH; } bool IsInboundConn() const { return m_conn_type == ConnectionType::INBOUND; } bool ExpectServicesFromConn() const { switch (m_conn_type) { case ConnectionType::INBOUND: case ConnectionType::MANUAL: case ConnectionType::FEELER: return false; case ConnectionType::OUTBOUND_FULL_RELAY: case ConnectionType::BLOCK_RELAY: case ConnectionType::ADDR_FETCH: return true; } // no default case, so the compiler can warn about missing cases assert(false); } /** * Get network the peer connected through. * * Returns Network::NET_ONION for *inbound* onion connections, * and CNetAddr::GetNetClass() otherwise. The latter cannot be used directly * because it doesn't detect the former, and it's not the responsibility of * the CNetAddr class to know the actual network a peer is connected * through. * * @return network the peer connected through. */ Network ConnectedThroughNetwork() const; protected: mapMsgCmdSize mapSendBytesPerMsgCmd; mapMsgCmdSize mapRecvBytesPerMsgCmd GUARDED_BY(cs_vRecv); public: struct TxRelay { mutable RecursiveMutex cs_filter; // 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 GUARDED_BY(cs_filter){false}; std::unique_ptr pfilter PT_GUARDED_BY(cs_filter) GUARDED_BY(cs_filter){nullptr}; mutable RecursiveMutex cs_tx_inventory; CRollingBloomFilter filterInventoryKnown GUARDED_BY(cs_tx_inventory){ 50000, 0.000001}; // 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 GUARDED_BY(cs_tx_inventory); // Used for BIP35 mempool sending bool fSendMempool GUARDED_BY(cs_tx_inventory){false}; // Last time a "MEMPOOL" request was serviced. std::atomic m_last_mempool_req{0s}; std::chrono::microseconds nNextInvSend{0}; RecursiveMutex cs_feeFilter; // Minimum fee rate with which to filter inv's to this node Amount minFeeFilter GUARDED_BY(cs_feeFilter){Amount::zero()}; Amount lastSentFeeFilter{Amount::zero()}; std::chrono::microseconds m_next_send_feefilter{0}; }; // m_tx_relay == nullptr if we're not relaying transactions with this peer std::unique_ptr m_tx_relay; struct ProofRelay { mutable RecursiveMutex cs_proof_inventory; std::set setInventoryProofToSend GUARDED_BY(cs_proof_inventory); // Prevent sending proof invs if the peer already knows about them CRollingBloomFilter filterProofKnown GUARDED_BY(cs_proof_inventory){ 10000, 0.000001}; std::chrono::microseconds nextInvSend{0}; }; // m_proof_relay == nullptr if we're not relaying proofs with this peer std::unique_ptr m_proof_relay; class AvalancheState { /** * The inventories polled and voted couters since last score * computation, stored as a pair of uint32_t with the poll counter * being the 32 lowest bits and the vote counter the 32 highest bits. */ std::atomic invCounters; /** The last computed score */ std::atomic availabilityScore; /** * Protect the sequence of operations required for updating the * statistics. */ Mutex cs_statistics; public: CPubKey pubkey; AvalancheState() : invCounters(0), availabilityScore(0.) {} /** The node was polled for count invs */ void invsPolled(uint32_t count); /** The node voted for count invs */ void invsVoted(uint32_t count); /** * The availability score is calculated using an exponentially weighted * average. * This has several interesting properties: * - The most recent polls/responses have more weight than the previous * ones. A node that recently stopped answering will see its ratio * decrease quickly. * - This is a low-pass filter, so it causes delay. This means that a * node needs to have a track record for the ratio to be high. A node * that has been little requested will have a lower ratio than a node * that failed to answer a few polls but answered a lot of them. * - It is cheap to compute. * * This is expected to be called at a fixed interval of * AVALANCHE_STATISTICS_REFRESH_PERIOD. */ void updateAvailabilityScore(); double getAvailabilityScore() const; }; // m_avalanche_state == nullptr if we're not using avalanche with this peer std::unique_ptr m_avalanche_state; /** * UNIX epoch time of the last block received from this peer that we had * not yet seen (e.g. not already received from another peer), that passed * preliminary validity checks and was saved to disk, even if we don't * connect the block or it eventually fails connection. Used as an inbound * peer eviction criterium in CConnman::AttemptToEvictConnection. */ std::atomic nLastBlockTime{0}; /** * UNIX epoch time of the last transaction received from this peer that we * had not yet seen (e.g. not already received from another peer) and that * was accepted into our mempool. Used as an inbound peer eviction criterium * in CConnman::AttemptToEvictConnection. */ std::atomic nLastTXTime{0}; /** * UNIX epoch time of the last proof received from this peer that we * had not yet seen (e.g. not already received from another peer) and that * was accepted into our proof pool. Used as an inbound peer eviction * criterium in CConnman::AttemptToEvictConnection. */ std::atomic nLastProofTime{0}; /** Last measured round-trip time. Used only for RPC/GUI stats/debugging.*/ std::atomic m_last_ping_time{0us}; /** * Lowest measured round-trip time. Used as an inbound peer eviction * criterium in CConnman::AttemptToEvictConnection. */ std::atomic m_min_ping_time{ std::chrono::microseconds::max()}; CNode(NodeId id, ServiceFlags nLocalServicesIn, SOCKET hSocketIn, const CAddress &addrIn, uint64_t nKeyedNetGroupIn, uint64_t nLocalHostNonceIn, uint64_t nLocalExtraEntropyIn, const CAddress &addrBindIn, const std::string &addrNameIn, ConnectionType conn_type_in, bool inbound_onion = false); ~CNode(); CNode(const CNode &) = delete; CNode &operator=(const CNode &) = delete; /** * A ping-pong round trip has completed successfully. Update latest and * minimum ping times. */ void PongReceived(std::chrono::microseconds ping_time) { m_last_ping_time = ping_time; m_min_ping_time = std::min(m_min_ping_time.load(), ping_time); } private: const NodeId id; const uint64_t nLocalHostNonce; const uint64_t nLocalExtraEntropy; const ConnectionType m_conn_type; std::atomic m_greatest_common_version{INIT_PROTO_VERSION}; //! Services offered to this peer. //! //! This is supplied by the parent CConnman during peer connection //! (CConnman::ConnectNode()) from its attribute of the same name. //! //! This is const because there is no protocol defined for renegotiating //! services initially offered to a peer. The set of local services we //! offer should not change after initialization. //! //! An interesting example of this is NODE_NETWORK and initial block //! download: a node which starts up from scratch doesn't have any blocks //! to serve, but still advertises NODE_NETWORK because it will eventually //! fulfill this role after IBD completes. P2P code is written in such a //! way that it can gracefully handle peers who don't make good on their //! service advertisements. const ServiceFlags nLocalServices; NetPermissionFlags m_permissionFlags{PF_NONE}; // Used only by SocketHandler thread std::list vRecvMsg; mutable RecursiveMutex cs_addrName; std::string addrName GUARDED_BY(cs_addrName); // Our address, as reported by the peer CService addrLocal GUARDED_BY(cs_addrLocal); mutable RecursiveMutex cs_addrLocal; //! Whether this peer connected via our Tor onion service. const bool m_inbound_onion{false}; public: NodeId GetId() const { return id; } uint64_t GetLocalNonce() const { return nLocalHostNonce; } uint64_t GetLocalExtraEntropy() const { return nLocalExtraEntropy; } int GetRefCount() const { assert(nRefCount >= 0); return nRefCount; } /** * Receive bytes from the buffer and deserialize them into messages. * * @param[in] msg_bytes The raw data * @param[out] complete Set True if at least one message has been * deserialized and is ready to be processed * @return True if the peer should stay connected, * False if the peer should be disconnected from. */ bool ReceiveMsgBytes(const Config &config, Span msg_bytes, bool &complete); void SetCommonVersion(int greatest_common_version) { Assume(m_greatest_common_version == INIT_PROTO_VERSION); m_greatest_common_version = greatest_common_version; } int GetCommonVersion() const { return m_greatest_common_version; } CService GetAddrLocal() const; //! May not be called more than once void SetAddrLocal(const CService &addrLocalIn); CNode *AddRef() { nRefCount++; return this; } void Release() { nRefCount--; } void AddKnownTx(const TxId &txid) { if (m_tx_relay != nullptr) { LOCK(m_tx_relay->cs_tx_inventory); m_tx_relay->filterInventoryKnown.insert(txid); } } void PushTxInventory(const TxId &txid) { if (m_tx_relay == nullptr) { return; } LOCK(m_tx_relay->cs_tx_inventory); if (!m_tx_relay->filterInventoryKnown.contains(txid)) { m_tx_relay->setInventoryTxToSend.insert(txid); } } void AddKnownProof(const avalanche::ProofId &proofid) { if (m_proof_relay != nullptr) { LOCK(m_proof_relay->cs_proof_inventory); m_proof_relay->filterProofKnown.insert(proofid); } } void PushProofInventory(const avalanche::ProofId &proofid) { if (m_proof_relay == nullptr) { return; } LOCK(m_proof_relay->cs_proof_inventory); if (!m_proof_relay->filterProofKnown.contains(proofid)) { m_proof_relay->setInventoryProofToSend.insert(proofid); } } void CloseSocketDisconnect(); void copyStats(CNodeStats &stats); ServiceFlags GetLocalServices() const { return nLocalServices; } std::string GetAddrName() const; //! Sets the addrName only if it was not previously set void MaybeSetAddrName(const std::string &addrNameIn); std::string ConnectionTypeAsString() const; }; /** * Interface for message handling */ class NetEventsInterface { public: /** Initialize a peer (setup state, queue any initial messages) */ virtual void InitializeNode(const Config &config, CNode *pnode) = 0; /** Handle removal of a peer (clear state) */ virtual void FinalizeNode(const Config &config, const CNode &node, bool &update_connection_time) = 0; /** * Process protocol messages received from a given node * * @param[in] config The applicable configuration object. * @param[in] pnode The node which we have received messages * from. * @param[in] interrupt Interrupt condition for processing threads * @return True if there is more work to be done */ virtual bool ProcessMessages(const Config &config, CNode *pnode, std::atomic &interrupt) = 0; /** * Send queued protocol messages to a given node. * * @param[in] config The applicable configuration object. * @param[in] pnode The node which we are sending messages to. * @return True if there is more work to be done */ virtual bool SendMessages(const Config &config, CNode *pnode) EXCLUSIVE_LOCKS_REQUIRED(pnode->cs_sendProcessing) = 0; protected: /** * Protected destructor so that instances can only be deleted by derived * classes. If that restriction is no longer desired, this should be made * public and virtual. */ ~NetEventsInterface() = default; }; namespace { struct CConnmanTest; } class NetEventsInterface; class CConnman { public: enum NumConnections { CONNECTIONS_NONE = 0, CONNECTIONS_IN = (1U << 0), CONNECTIONS_OUT = (1U << 1), CONNECTIONS_ALL = (CONNECTIONS_IN | CONNECTIONS_OUT), }; struct Options { ServiceFlags nLocalServices = NODE_NONE; int nMaxConnections = 0; int m_max_outbound_full_relay = 0; int m_max_outbound_block_relay = 0; int nMaxAddnode = 0; int nMaxFeeler = 0; CClientUIInterface *uiInterface = nullptr; NetEventsInterface *m_msgproc = nullptr; BanMan *m_banman = nullptr; unsigned int nSendBufferMaxSize = 0; unsigned int nReceiveFloodSize = 0; uint64_t nMaxOutboundLimit = 0; int64_t m_peer_connect_timeout = DEFAULT_PEER_CONNECT_TIMEOUT; std::vector vSeedNodes; std::vector vWhitelistedRange; std::vector vWhiteBinds; std::vector vBinds; std::vector onion_binds; bool m_use_addrman_outgoing = true; std::vector m_specified_outgoing; std::vector m_added_nodes; }; void Init(const Options &connOptions) { nLocalServices = connOptions.nLocalServices; nMaxConnections = connOptions.nMaxConnections; m_use_addrman_outgoing = connOptions.m_use_addrman_outgoing; nMaxAddnode = connOptions.nMaxAddnode; nMaxFeeler = connOptions.nMaxFeeler; { // Lock cs_main to prevent a potential race with the peer validation // logic thread. LOCK(::cs_main); m_max_outbound_full_relay = std::min(connOptions.m_max_outbound_full_relay, connOptions.nMaxConnections); m_max_outbound_block_relay = connOptions.m_max_outbound_block_relay; m_max_outbound = m_max_outbound_full_relay + m_max_outbound_block_relay + nMaxFeeler; } clientInterface = connOptions.uiInterface; m_banman = connOptions.m_banman; m_msgproc = connOptions.m_msgproc; nSendBufferMaxSize = connOptions.nSendBufferMaxSize; nReceiveFloodSize = connOptions.nReceiveFloodSize; m_peer_connect_timeout = connOptions.m_peer_connect_timeout; { LOCK(cs_totalBytesSent); nMaxOutboundLimit = connOptions.nMaxOutboundLimit; } vWhitelistedRange = connOptions.vWhitelistedRange; { LOCK(cs_vAddedNodes); vAddedNodes = connOptions.m_added_nodes; } m_onion_binds = connOptions.onion_binds; } CConnman(const Config &configIn, uint64_t seed0, uint64_t seed1, bool network_active = true); ~CConnman(); bool Start(CScheduler &scheduler, const Options &options); void StopThreads(); void StopNodes(); void Stop() { StopThreads(); StopNodes(); }; void Interrupt(); bool GetNetworkActive() const { return fNetworkActive; }; bool GetUseAddrmanOutgoing() const { return m_use_addrman_outgoing; }; void SetNetworkActive(bool active); void OpenNetworkConnection(const CAddress &addrConnect, bool fCountFailure, CSemaphoreGrant *grantOutbound, const char *strDest, ConnectionType conn_type); bool CheckIncomingNonce(uint64_t nonce); bool ForNode(NodeId id, std::function func); void PushMessage(CNode *pnode, CSerializedNetMsg &&msg); using NodeFn = std::function; void ForEachNode(const NodeFn &func) { LOCK(cs_vNodes); for (auto &&node : vNodes) { if (NodeFullyConnected(node)) { func(node); } } }; void ForEachNode(const NodeFn &func) const { LOCK(cs_vNodes); for (auto &&node : vNodes) { if (NodeFullyConnected(node)) { func(node); } } }; - template - void ForEachNodeThen(Callable &&pre, CallableAfter &&post) { - LOCK(cs_vNodes); - for (auto &&node : vNodes) { - if (NodeFullyConnected(node)) { - pre(node); - } - } - post(); - }; - - template - void ForEachNodeThen(Callable &&pre, CallableAfter &&post) const { - LOCK(cs_vNodes); - for (auto &&node : vNodes) { - if (NodeFullyConnected(node)) { - pre(node); - } - } - post(); - }; - // Addrman functions void SetServices(const CService &addr, ServiceFlags nServices); void MarkAddressGood(const CAddress &addr); bool AddNewAddresses(const std::vector &vAddr, const CAddress &addrFrom, int64_t nTimePenalty = 0); std::vector GetAddresses(size_t max_addresses, size_t max_pct); /** * Cache is used to minimize topology leaks, so it should * be used for all non-trusted calls, for example, p2p. * A non-malicious call (from RPC or a peer with addr permission) should * call the function without a parameter to avoid using the cache. */ std::vector GetAddresses(CNode &requestor, size_t max_addresses, size_t max_pct); // This allows temporarily exceeding m_max_outbound_full_relay, with the // goal of finding a peer that is better than all our current peers. void SetTryNewOutboundPeer(bool flag); bool GetTryNewOutboundPeer(); void StartExtraBlockRelayPeers() { LogPrint(BCLog::NET, "net: enabling extra block-relay-only peers\n"); m_start_extra_block_relay_peers = true; } // Return the number of outbound peers we have in excess of our target (eg, // if we previously called SetTryNewOutboundPeer(true), and have since set // to false, we may have extra peers that we wish to disconnect). This may // return a value less than (num_outbound_connections - num_outbound_slots) // in cases where some outbound connections are not yet fully connected, or // not yet fully disconnected. int GetExtraFullOutboundCount(); // Count the number of block-relay-only peers we have over our limit. int GetExtraBlockRelayCount(); bool AddNode(const std::string &node); bool RemoveAddedNode(const std::string &node); std::vector GetAddedNodeInfo(); /** * Attempts to open a connection. Currently only used from tests. * * @param[in] address Address of node to try connecting to * @param[in] conn_type ConnectionType::OUTBOUND or * ConnectionType::BLOCK_RELAY or ConnectionType::ADDR_FETCH * @return bool Returns false if there are no available * slots for this connection: * - conn_type not a supported ConnectionType * - Max total outbound connection capacity filled * - Max connection capacity for type is filled */ bool AddConnection(const std::string &address, ConnectionType conn_type); size_t GetNodeCount(NumConnections num); void GetNodeStats(std::vector &vstats); bool DisconnectNode(const std::string &node); bool DisconnectNode(const CSubNet &subnet); bool DisconnectNode(const CNetAddr &addr); bool DisconnectNode(NodeId id); //! Used to convey which local services we are offering peers during node //! connection. //! //! The data returned by this is used in CNode construction, //! which is used to advertise which services we are offering //! that peer during `net_processing.cpp:PushNodeVersion()`. ServiceFlags GetLocalServices() const; uint64_t GetMaxOutboundTarget(); std::chrono::seconds 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. bool OutboundTargetReached(bool historicalBlockServingLimit); //! response the bytes left in the current max outbound cycle in case of no //! limit, it will always response 0 uint64_t GetOutboundTargetBytesLeft(); //! returns the time in second left in the current max outbound cycle in //! case of no limit, it will always return 0 std::chrono::seconds GetMaxOutboundTimeLeftInCycle(); uint64_t GetTotalBytesRecv(); uint64_t GetTotalBytesSent(); /** Get a unique deterministic randomizer. */ CSipHasher GetDeterministicRandomizer(uint64_t id) const; unsigned int GetReceiveFloodSize() const; void WakeMessageHandler(); /** * Attempts to obfuscate tx time through exponentially distributed emitting. * Works assuming that a single interval is used. * Variable intervals will result in privacy decrease. */ std::chrono::microseconds PoissonNextSendInbound(std::chrono::microseconds now, std::chrono::seconds average_interval); void SetAsmap(std::vector asmap) { addrman.m_asmap = std::move(asmap); } /** * Return true if the peer has been connected for long enough to do * inactivity checks. */ bool RunInactivityChecks(const CNode &node) const; private: struct ListenSocket { public: SOCKET socket; inline void AddSocketPermissionFlags(NetPermissionFlags &flags) const { NetPermissions::AddFlag(flags, m_permissions); } ListenSocket(SOCKET socket_, NetPermissionFlags permissions_) : socket(socket_), m_permissions(permissions_) {} private: NetPermissionFlags m_permissions; }; bool BindListenPort(const CService &bindAddr, bilingual_str &strError, NetPermissionFlags permissions); bool Bind(const CService &addr, unsigned int flags, NetPermissionFlags permissions); bool InitBinds(const std::vector &binds, const std::vector &whiteBinds, const std::vector &onion_binds); void ThreadOpenAddedConnections(); void AddAddrFetch(const std::string &strDest); void ProcessAddrFetch(); void ThreadOpenConnections(std::vector connect); void ThreadMessageHandler(); void AcceptConnection(const ListenSocket &hListenSocket); void DisconnectNodes(); void NotifyNumConnectionsChanged(); /** Return true if the peer is inactive and should be disconnected. */ bool InactivityCheck(const CNode &node) const; bool GenerateSelectSet(std::set &recv_set, std::set &send_set, std::set &error_set); void SocketEvents(std::set &recv_set, std::set &send_set, std::set &error_set); void SocketHandler(); void ThreadSocketHandler(); void ThreadDNSAddressSeed(); uint64_t CalculateKeyedNetGroup(const CAddress &ad) const; CNode *FindNode(const CNetAddr &ip); CNode *FindNode(const CSubNet &subNet); CNode *FindNode(const std::string &addrName); CNode *FindNode(const CService &addr); /** * Determine whether we're already connected to a given address, in order to * avoid initiating duplicate connections. */ bool AlreadyConnectedToAddress(const CAddress &addr); bool AttemptToEvictConnection(); CNode *ConnectNode(CAddress addrConnect, const char *pszDest, bool fCountFailure, ConnectionType conn_type); void AddWhitelistPermissionFlags(NetPermissionFlags &flags, const CNetAddr &addr) const; void DeleteNode(CNode *pnode); NodeId GetNewNodeId(); size_t SocketSendData(CNode &node) const EXCLUSIVE_LOCKS_REQUIRED(node.cs_vSend); void DumpAddresses(); // Network stats void RecordBytesRecv(uint64_t bytes); void RecordBytesSent(uint64_t bytes); /** * Return vector of current BLOCK_RELAY peers. */ std::vector GetCurrentBlockRelayOnlyConns() const; // Whether the node should be passed out in ForEach* callbacks static bool NodeFullyConnected(const CNode *pnode); const Config *config; // Network usage totals RecursiveMutex cs_totalBytesRecv; RecursiveMutex cs_totalBytesSent; uint64_t nTotalBytesRecv GUARDED_BY(cs_totalBytesRecv){0}; uint64_t nTotalBytesSent GUARDED_BY(cs_totalBytesSent){0}; // outbound limit & stats uint64_t nMaxOutboundTotalBytesSentInCycle GUARDED_BY(cs_totalBytesSent){0}; std::chrono::seconds nMaxOutboundCycleStartTime GUARDED_BY(cs_totalBytesSent){0}; uint64_t nMaxOutboundLimit GUARDED_BY(cs_totalBytesSent); // P2P timeout in seconds int64_t m_peer_connect_timeout; // Whitelisted ranges. Any node connecting from these is automatically // whitelisted (as well as those connecting to whitelisted binds). std::vector vWhitelistedRange; unsigned int nSendBufferMaxSize{0}; unsigned int nReceiveFloodSize{0}; std::vector vhListenSocket; std::atomic fNetworkActive{true}; bool fAddressesInitialized{false}; CAddrMan addrman; std::deque m_addr_fetches GUARDED_BY(m_addr_fetches_mutex); RecursiveMutex m_addr_fetches_mutex; std::vector vAddedNodes GUARDED_BY(cs_vAddedNodes); RecursiveMutex cs_vAddedNodes; std::vector vNodes GUARDED_BY(cs_vNodes); std::list vNodesDisconnected; mutable RecursiveMutex cs_vNodes; std::atomic nLastNodeId{0}; unsigned int nPrevNodeCount{0}; /** * Cache responses to addr requests to minimize privacy leak. * Attack example: scraping addrs in real-time may allow an attacker * to infer new connections of the victim by detecting new records * with fresh timestamps (per self-announcement). */ struct CachedAddrResponse { std::vector m_addrs_response_cache; std::chrono::microseconds m_cache_entry_expiration{0}; }; /** * Addr responses stored in different caches * per (network, local socket) prevent cross-network node identification. * If a node for example is multi-homed under Tor and IPv6, * a single cache (or no cache at all) would let an attacker * to easily detect that it is the same node by comparing responses. * Indexing by local socket prevents leakage when a node has multiple * listening addresses on the same network. * * The used memory equals to 1000 CAddress records (or around 40 bytes) per * distinct Network (up to 5) we have/had an inbound peer from, * resulting in at most ~196 KB. Every separate local socket may * add up to ~196 KB extra. */ std::map m_addr_response_caches; /** * Services this instance offers. * * This data is replicated in each CNode instance we create during peer * connection (in ConnectNode()) under a member also called * nLocalServices. * * This data is not marked const, but after being set it should not * change. See the note in CNode::nLocalServices documentation. * * \sa CNode::nLocalServices */ ServiceFlags nLocalServices; std::unique_ptr semOutbound; std::unique_ptr semAddnode; int nMaxConnections; // How many full-relay (tx, block, addr) outbound peers we want int m_max_outbound_full_relay; // How many block-relay only outbound peers we want // We do not relay tx or addr messages with these peers int m_max_outbound_block_relay; int nMaxAddnode; int nMaxFeeler; int m_max_outbound; bool m_use_addrman_outgoing; CClientUIInterface *clientInterface; NetEventsInterface *m_msgproc; /** * Pointer to this node's banman. May be nullptr - check existence before * dereferencing. */ BanMan *m_banman; /** * Addresses that were saved during the previous clean shutdown. We'll * attempt to make block-relay-only connections to them. */ std::vector m_anchors; /** SipHasher seeds for deterministic randomness */ const uint64_t nSeed0, nSeed1; /** flag for waking the message processor. */ bool fMsgProcWake GUARDED_BY(mutexMsgProc); std::condition_variable condMsgProc; Mutex mutexMsgProc; std::atomic flagInterruptMsgProc{false}; CThreadInterrupt interruptNet; std::thread threadDNSAddressSeed; std::thread threadSocketHandler; std::thread threadOpenAddedConnections; std::thread threadOpenConnections; std::thread threadMessageHandler; /** * flag for deciding to connect to an extra outbound peer, in excess of * m_max_outbound_full_relay. This takes the place of a feeler connection. */ std::atomic_bool m_try_another_outbound_peer; /** * flag for initiating extra block-relay-only peer connections. * this should only be enabled after initial chain sync has occurred, * as these connections are intended to be short-lived and low-bandwidth. */ std::atomic_bool m_start_extra_block_relay_peers{false}; std::atomic m_next_send_inv_to_incoming{0us}; /** * A vector of -bind=
:=onion arguments each of which is * an address and port that are designated for incoming Tor connections. */ std::vector m_onion_binds; friend struct ::CConnmanTest; friend struct ConnmanTestMsg; }; /** * Return a timestamp in the future (in microseconds) for exponentially * distributed events. */ std::chrono::microseconds PoissonNextSend(std::chrono::microseconds now, std::chrono::seconds average_interval); std::string getSubVersionEB(uint64_t MaxBlockSize); std::string userAgent(const Config &config); struct NodeEvictionCandidate { NodeId id; int64_t nTimeConnected; std::chrono::microseconds m_min_ping_time; int64_t nLastBlockTime; int64_t nLastProofTime; int64_t nLastTXTime; bool fRelevantServices; bool fRelayTxes; bool fBloomFilter; uint64_t nKeyedNetGroup; bool prefer_evict; bool m_is_local; double availabilityScore; }; [[nodiscard]] std::optional SelectNodeToEvict(std::vector &&vEvictionCandidates); #endif // BITCOIN_NET_H