git / moonbite-core / src/net_processing.cpp · raw

// Copyright (c) 2009-2010 Satoshi Nakamoto// Copyright (c) 2009-2020 The Bitcoin Core developers// Distributed under the MIT software license, see the accompanying// file COPYING or http://www.opensource.org/licenses/mit-license.php.#include <net_processing.h>#include <addrman.h>#include <banman.h>#include <blockencodings.h>#include <blockfilter.h>#include <chainparams.h>#include <consensus/validation.h>#include <hash.h>#include <index/blockfilterindex.h>#include <merkleblock.h>#include <mw/mmr/Segment.h>#include <netbase.h>#include <netmessagemaker.h>#include <policy/fees.h>#include <policy/policy.h>#include <primitives/block.h>#include <primitives/transaction.h>#include <random.h>#include <reverse_iterator.h>#include <scheduler.h>#include <streams.h>#include <tinyformat.h>#include <txmempool.h>#include <util/check.h> // For NDEBUG compile time check#include <util/strencodings.h>#include <util/system.h>#include <validation.h>#include <memory>#include <typeinfo>/** Expiration time for orphan transactions in seconds */static constexpr int64_t ORPHAN_TX_EXPIRE_TIME = 20 * 60;/** Minimum time between orphan transactions expire time checks in seconds */static constexpr int64_t ORPHAN_TX_EXPIRE_INTERVAL = 5 * 60;/** How long to cache transactions in mapRelay for normal relay */static constexpr std::chrono::seconds RELAY_TX_CACHE_TIME = std::chrono::minutes{15};/** How long a transaction has to be in the mempool before it can unconditionally be relayed (even when not in mapRelay). */static constexpr std::chrono::seconds UNCONDITIONAL_RELAY_DELAY = std::chrono::minutes{2};/** Headers download timeout expressed in microseconds *  Timeout = base + per_header * (expected number of headers) */static constexpr int64_t HEADERS_DOWNLOAD_TIMEOUT_BASE = 15 * 60 * 1000000; // 15 minutesstatic constexpr int64_t HEADERS_DOWNLOAD_TIMEOUT_PER_HEADER = 1000; // 1ms/header/** Protect at least this many outbound peers from disconnection due to slow/ * behind headers chain. */static constexpr int32_t MAX_OUTBOUND_PEERS_TO_PROTECT_FROM_DISCONNECT = 4;/** Timeout for (unprotected) outbound peers to sync to our chainwork, in seconds */static constexpr int64_t CHAIN_SYNC_TIMEOUT = 20 * 60; // 20 minutes/** How frequently to check for stale tips, in seconds */static constexpr int64_t STALE_CHECK_INTERVAL = 2.5 * 60; // 2.5 minutes/** How frequently to check for extra outbound peers and disconnect, in seconds */static constexpr int64_t EXTRA_PEER_CHECK_INTERVAL = 45;/** Minimum time an outbound-peer-eviction candidate must be connected for, in order to evict, in seconds */static constexpr int64_t MINIMUM_CONNECT_TIME = 30;/** SHA256("main address relay")[0:8] */static constexpr uint64_t RANDOMIZER_ID_ADDRESS_RELAY = 0x3cac0035b5866b90ULL;/// Age after which a stale block will no longer be served if requested as/// protection against fingerprinting. Set to one month, denominated in seconds.static constexpr int STALE_RELAY_AGE_LIMIT = 30 * 24 * 60 * 60;/// Age after which a block is considered historical for purposes of rate/// limiting block relay. Set to one week, denominated in seconds.static constexpr int HISTORICAL_BLOCK_AGE = 7 * 24 * 60 * 60;/** Time between pings automatically sent out for latency probing and keepalive */static constexpr std::chrono::minutes PING_INTERVAL{2};/** The maximum number of entries in a locator */static const unsigned int MAX_LOCATOR_SZ = 101;/** The maximum number of entries in an 'inv' protocol message */static const unsigned int MAX_INV_SZ = 50000;/** Maximum number of in-flight transaction requests from a peer. It is not a hard limit, but the threshold at which *  point the OVERLOADED_PEER_TX_DELAY kicks in. */static constexpr int32_t MAX_PEER_TX_REQUEST_IN_FLIGHT = 100;/** Maximum number of transactions to consider for requesting, per peer. It provides a reasonable DoS limit to *  per-peer memory usage spent on announcements, while covering peers continuously sending INVs at the maximum *  rate (by our own policy, see INVENTORY_BROADCAST_PER_SECOND) for several minutes, while not receiving *  the actual transaction (from any peer) in response to requests for them. */static constexpr int32_t MAX_PEER_TX_ANNOUNCEMENTS = 5000;/** How long to delay requesting transactions via txids, if we have wtxid-relaying peers */static constexpr auto TXID_RELAY_DELAY = std::chrono::seconds{2};/** How long to delay requesting transactions from non-preferred peers */static constexpr auto NONPREF_PEER_TX_DELAY = std::chrono::seconds{2};/** How long to delay requesting transactions from overloaded peers (see MAX_PEER_TX_REQUEST_IN_FLIGHT). */static constexpr auto OVERLOADED_PEER_TX_DELAY = std::chrono::seconds{2};/** How long to wait (in microseconds) before downloading a transaction from an additional peer */static constexpr std::chrono::microseconds GETDATA_TX_INTERVAL{std::chrono::seconds{60}};/** Limit to avoid sending big packets. Not used in processing incoming GETDATA for compatibility */static const unsigned int MAX_GETDATA_SZ = 1000;/** Number of blocks that can be requested at any given time from a single peer. */static const int MAX_BLOCKS_IN_TRANSIT_PER_PEER = 16;/** Timeout in seconds during which a peer must stall block download progress before being disconnected. */static const unsigned int BLOCK_STALLING_TIMEOUT = 2;/** Number of headers sent in one getheaders result. We rely on the assumption that if a peer sends *  less than this number, we reached its tip. Changing this value is a protocol upgrade. */static const unsigned int MAX_HEADERS_RESULTS = 2000;/** Maximum depth of blocks we're willing to serve as compact blocks to peers *  when requested. For older blocks, a regular BLOCK response will be sent. */static const int MAX_CMPCTBLOCK_DEPTH = 5;/** Maximum depth of blocks we're willing to respond to GETBLOCKTXN requests for. */static const int MAX_BLOCKTXN_DEPTH = 10;/** Maximum depth of blocks we're willing to serve MWEB leafsets for. */static const int MAX_MWEB_LEAFSET_DEPTH = 10;/** Maximum number of MWEB UTXOs that can be requested in a batch. */static const uint16_t MAX_REQUESTED_MWEB_UTXOS = 4096;/** Size of the "block download window": how far ahead of our current height do we fetch? *  Larger windows tolerate larger download speed differences between peer, but increase the potential *  degree of disordering of blocks on disk (which make reindexing and pruning harder). We'll probably *  want to make this a per-peer adaptive value at some point. */static const unsigned int BLOCK_DOWNLOAD_WINDOW = 1024;/** Block download timeout base, expressed in millionths of the block interval (i.e. 10 min) */static const int64_t BLOCK_DOWNLOAD_TIMEOUT_BASE = 1000000;/** Additional block download timeout per parallel downloading peer (i.e. 5 min) */static const int64_t BLOCK_DOWNLOAD_TIMEOUT_PER_PEER = 500000;/** Maximum number of headers to announce when relaying blocks with headers message.*/static const unsigned int MAX_BLOCKS_TO_ANNOUNCE = 8;/** Maximum number of unconnecting headers announcements before DoS score */static const int MAX_UNCONNECTING_HEADERS = 10;/** Minimum blocks required to signal NODE_NETWORK_LIMITED */static const unsigned int NODE_NETWORK_LIMITED_MIN_BLOCKS = 288;/** Average delay between local address broadcasts */static constexpr std::chrono::hours AVG_LOCAL_ADDRESS_BROADCAST_INTERVAL{24};/** Average delay between peer address broadcasts */static constexpr std::chrono::seconds AVG_ADDRESS_BROADCAST_INTERVAL{30};/** Average delay between trickled inventory transmissions in seconds. *  Blocks and peers with noban permission bypass this, outbound peers get half this delay. */static const unsigned int INVENTORY_BROADCAST_INTERVAL = 5;/** Maximum rate of inventory items to send per second. *  Limits the impact of low-fee transaction floods. */static constexpr unsigned int INVENTORY_BROADCAST_PER_SECOND = 7;/** Maximum number of inventory items to send per transmission. */static constexpr unsigned int INVENTORY_BROADCAST_MAX = INVENTORY_BROADCAST_PER_SECOND * INVENTORY_BROADCAST_INTERVAL;/** The number of most recently announced transactions a peer can request. */static constexpr unsigned int INVENTORY_MAX_RECENT_RELAY = 3500;/** Verify that INVENTORY_MAX_RECENT_RELAY is enough to cache everything typically *  relayed before unconditional relay from the mempool kicks in. This is only a *  lower bound, and it should be larger to account for higher inv rate to outbound *  peers, and random variations in the broadcast mechanism. */static_assert(INVENTORY_MAX_RECENT_RELAY >= INVENTORY_BROADCAST_PER_SECOND * UNCONDITIONAL_RELAY_DELAY / std::chrono::seconds{1}, "INVENTORY_RELAY_MAX too low");/** Average delay between feefilter broadcasts in seconds. */static constexpr unsigned int AVG_FEEFILTER_BROADCAST_INTERVAL = 10 * 60;/** Maximum feefilter broadcast delay after significant change. */static constexpr unsigned int MAX_FEEFILTER_CHANGE_DELAY = 5 * 60;/** Maximum number of compact filters that may be requested with one getcfilters. See BIP 157. */static constexpr uint32_t MAX_GETCFILTERS_SIZE = 1000;/** Maximum number of cf hashes that may be requested with one getcfheaders. See BIP 157. */static constexpr uint32_t MAX_GETCFHEADERS_SIZE = 2000;/** the maximum percentage of addresses from our addrman to return in response to a getaddr message. */static constexpr size_t MAX_PCT_ADDR_TO_SEND = 23;/** The maximum rate of address records we're willing to process on average. Can be bypassed using *  the NetPermissionFlags::Addr permission. */static constexpr double MAX_ADDR_RATE_PER_SECOND{0.1};/** The soft limit of the address processing token bucket (the regular MAX_ADDR_RATE_PER_SECOND *  based increments won't go above this, but the MAX_ADDR_TO_SEND increment following GETADDR *  is exempt from this limit). */static constexpr size_t MAX_ADDR_PROCESSING_TOKEN_BUCKET{MAX_ADDR_TO_SEND};struct COrphanTx {    // When modifying, adapt the copy of this definition in tests/DoS_tests.    CTransactionRef tx;    NodeId fromPeer;    int64_t nTimeExpire;    size_t list_pos;};/** Guards orphan transactions and extra txs for compact blocks */RecursiveMutex g_cs_orphans;/** Map from txid to orphan transaction record. Limited by *  -maxorphantx/DEFAULT_MAX_ORPHAN_TRANSACTIONS */std::map<uint256, COrphanTx> mapOrphanTransactions GUARDED_BY(g_cs_orphans);/** Index from wtxid into the mapOrphanTransactions to lookup orphan *  transactions using their witness ids. */std::map<uint256, std::map<uint256, COrphanTx>::iterator> g_orphans_by_wtxid GUARDED_BY(g_cs_orphans);void EraseOrphansFor(NodeId peer);// Internal stuffnamespace {    /** Number of nodes with fSyncStarted. */    int nSyncStarted GUARDED_BY(cs_main) = 0;    /**     * Sources of received blocks, saved to be able punish them when processing     * happens afterwards.     * Set mapBlockSource[hash].second to false if the node should not be     * punished if the block is invalid.     */    std::map<uint256, std::pair<NodeId, bool>> mapBlockSource GUARDED_BY(cs_main);    /**     * Filter for transactions that were recently rejected by     * AcceptToMemoryPool. These are not rerequested until the chain tip     * changes, at which point the entire filter is reset.     *     * Without this filter we'd be re-requesting txs from each of our peers,     * increasing bandwidth consumption considerably. For instance, with 100     * peers, half of which relay a tx we don't accept, that might be a 50x     * bandwidth increase. A flooding attacker attempting to roll-over the     * filter using minimum-sized, 60byte, transactions might manage to send     * 1000/sec if we have fast peers, so we pick 120,000 to give our peers a     * two minute window to send invs to us.     *     * Decreasing the false positive rate is fairly cheap, so we pick one in a     * million to make it highly unlikely for users to have issues with this     * filter.     *     * We typically only add wtxids to this filter. For non-segwit     * transactions, the txid == wtxid, so this only prevents us from     * re-downloading non-segwit transactions when communicating with     * non-wtxidrelay peers -- which is important for avoiding malleation     * attacks that could otherwise interfere with transaction relay from     * non-wtxidrelay peers. For communicating with wtxidrelay peers, having     * the reject filter store wtxids is exactly what we want to avoid     * redownload of a rejected transaction.     *     * In cases where we can tell that a segwit transaction will fail     * validation no matter the witness, we may add the txid of such     * transaction to the filter as well. This can be helpful when     * communicating with txid-relay peers or if we were to otherwise fetch a     * transaction via txid (eg in our orphan handling).     *     * Memory used: 1.3 MB     */    std::unique_ptr<CRollingBloomFilter> recentRejects GUARDED_BY(cs_main);    uint256 hashRecentRejectsChainTip GUARDED_BY(cs_main);    /*     * Filter for transactions that have been recently confirmed.     * We use this to avoid requesting transactions that have already been     * confirnmed.     */    Mutex g_cs_recent_confirmed_transactions;    std::unique_ptr<CRollingBloomFilter> g_recent_confirmed_transactions GUARDED_BY(g_cs_recent_confirmed_transactions);    /** Blocks that are in flight, and that are in the queue to be downloaded. */    struct QueuedBlock {        uint256 hash;        const CBlockIndex* pindex;                               //!< Optional.        bool fValidatedHeaders;                                  //!< Whether this block has validated headers at the time of request.        std::unique_ptr<PartiallyDownloadedBlock> partialBlock;  //!< Optional, used for CMPCTBLOCK downloads    };    std::map<uint256, std::pair<NodeId, std::list<QueuedBlock>::iterator> > mapBlocksInFlight GUARDED_BY(cs_main);    /** Stack of nodes which we have set to announce using compact blocks */    std::list<NodeId> lNodesAnnouncingHeaderAndIDs GUARDED_BY(cs_main);    /** Number of preferable block download peers. */    int nPreferredDownload GUARDED_BY(cs_main) = 0;    /** Number of peers from which we're downloading blocks. */    int nPeersWithValidatedDownloads GUARDED_BY(cs_main) = 0;    /** Number of peers with wtxid relay. */    int g_wtxid_relay_peers GUARDED_BY(cs_main) = 0;    /** Number of outbound peers with m_chain_sync.m_protect. */    int g_outbound_peers_with_protect_from_disconnect GUARDED_BY(cs_main) = 0;    /** When our tip was last updated. */    std::atomic<int64_t> g_last_tip_update(0);    /** Relay map (txid or wtxid -> CTransactionRef) */    typedef std::map<uint256, CTransactionRef> MapRelay;    MapRelay mapRelay GUARDED_BY(cs_main);    /** Expiration-time ordered list of (expire time, relay map entry) pairs. */    std::deque<std::pair<int64_t, MapRelay::iterator>> vRelayExpiration GUARDED_BY(cs_main);    struct IteratorComparator    {        template<typename I>        bool operator()(const I& a, const I& b) const        {            return &(*a) < &(*b);        }    };    /** Index from the parents' COutPoint into the mapOrphanTransactions. Used     *  to remove orphan transactions from the mapOrphanTransactions */    std::map<COutPoint, std::set<std::map<uint256, COrphanTx>::iterator, IteratorComparator>> mapOrphanTransactionsByPrev GUARDED_BY(g_cs_orphans);    /** Orphan transactions in vector for quick random eviction */    std::vector<std::map<uint256, COrphanTx>::iterator> g_orphan_list GUARDED_BY(g_cs_orphans);    /** Orphan/conflicted/etc transactions that are kept for compact block reconstruction.     *  The last -blockreconstructionextratxn/DEFAULT_BLOCK_RECONSTRUCTION_EXTRA_TXN of     *  these are kept in a ring buffer */    static std::vector<std::pair<uint256, CTransactionRef>> vExtraTxnForCompact GUARDED_BY(g_cs_orphans);    /** Offset into vExtraTxnForCompact to insert the next tx */    static size_t vExtraTxnForCompactIt GUARDED_BY(g_cs_orphans) = 0;} // namespacenamespace {/** * Maintain validation-specific state about nodes, protected by cs_main, instead * by CNode's own locks. This simplifies asynchronous operation, where * processing of incoming data is done after the ProcessMessage call returns, * and we're no longer holding the node's locks. */struct CNodeState {    //! The peer's address    const CService address;    //! Whether we have a fully established connection.    bool fCurrentlyConnected;    //! The best known block we know this peer has announced.    const CBlockIndex *pindexBestKnownBlock;    //! The hash of the last unknown block this peer has announced.    uint256 hashLastUnknownBlock;    //! The last full block we both have.    const CBlockIndex *pindexLastCommonBlock;    //! The best header we have sent our peer.    const CBlockIndex *pindexBestHeaderSent;    //! Length of current-streak of unconnecting headers announcements    int nUnconnectingHeaders;    //! Whether we've started headers synchronization with this peer.    bool fSyncStarted;    //! When to potentially disconnect peer for stalling headers download    int64_t nHeadersSyncTimeout;    //! Since when we're stalling block download progress (in microseconds), or 0.    int64_t nStallingSince;    std::list<QueuedBlock> vBlocksInFlight;    //! When the first entry in vBlocksInFlight started downloading. Don't care when vBlocksInFlight is empty.    int64_t nDownloadingSince;    int nBlocksInFlight;    int nBlocksInFlightValidHeaders;    //! Whether we consider this a preferred download peer.    bool fPreferredDownload;    //! Whether this peer wants invs or headers (when possible) for block announcements.    bool fPreferHeaders;    //! Whether this peer wants invs or cmpctblocks (when possible) for block announcements.    bool fPreferHeaderAndIDs;    /**      * Whether this peer will send us cmpctblocks if we request them.      * This is not used to gate request logic, as we really only care about fSupportsDesiredCmpctVersion,      * but is used as a flag to "lock in" the version of compact blocks (fWantsCmpctWitness) we send.      */    bool fProvidesHeaderAndIDs;    //! Whether this peer can give us witnesses    bool fHaveWitness;    //! Whether this peer can give us MWEB data    bool fHaveMWEB;    //! Whether this peer wants witnesses in cmpctblocks/blocktxns    bool fWantsCmpctWitness;    //! Whether this peer wants MWEB transactions in cmpctblocks/blocktxns    bool fWantsCmpctMWEB;    /**     * If we've announced NODE_WITNESS to this peer: whether the peer sends witnesses in cmpctblocks/blocktxns,     * otherwise: whether this peer sends non-witnesses in cmpctblocks/blocktxns.     */    bool fSupportsDesiredCmpctVersion;    int GetCmpctBlockVersion()    {        if (fWantsCmpctMWEB) {            return 3;        } else if (fWantsCmpctWitness) {            return 2;        } else {            return 1;        }    }    /** State used to enforce CHAIN_SYNC_TIMEOUT and EXTRA_PEER_CHECK_INTERVAL logic.      *      * Both are only in effect for outbound, non-manual, non-protected connections.      * Any peer protected (m_protect = true) is not chosen for eviction. A peer is      * marked as protected if all of these are true:      *   - its connection type is IsBlockOnlyConn() == false      *   - it gave us a valid connecting header      *   - we haven't reached MAX_OUTBOUND_PEERS_TO_PROTECT_FROM_DISCONNECT yet      *   - it has a better chain than we have      *      * CHAIN_SYNC_TIMEOUT: if a peer's best known block has less work than our tip,      * set a timeout CHAIN_SYNC_TIMEOUT seconds in the future:      *   - If at timeout their best known block now has more work than our tip      *     when the timeout was set, then either reset the timeout or clear it      *     (after comparing against our current tip's work)      *   - If at timeout their best known block still has less work than our      *     tip did when the timeout was set, then send a getheaders message,      *     and set a shorter timeout, HEADERS_RESPONSE_TIME seconds in future.      *     If their best known block is still behind when that new timeout is      *     reached, disconnect.      *      * EXTRA_PEER_CHECK_INTERVAL: after each interval, if we have too many outbound peers,      * drop the outbound one that least recently announced us a new block.      */    struct ChainSyncTimeoutState {        //! A timeout used for checking whether our peer has sufficiently synced        int64_t m_timeout;        //! A header with the work we require on our peer's chain        const CBlockIndex * m_work_header;        //! After timeout is reached, set to true after sending getheaders        bool m_sent_getheaders;        //! Whether this peer is protected from disconnection due to a bad/slow chain        bool m_protect;    };    ChainSyncTimeoutState m_chain_sync;    //! Time of last new block announcement    int64_t m_last_block_announcement;    //! Whether this peer is an inbound connection    bool m_is_inbound;    //! Whether this peer is a manual connection    bool m_is_manual_connection;    //! A rolling bloom filter of all announced tx CInvs to this peer.    CRollingBloomFilter m_recently_announced_invs = CRollingBloomFilter{INVENTORY_MAX_RECENT_RELAY, 0.000001};    //! Whether this peer relays txs via wtxid    bool m_wtxid_relay{false};    CNodeState(CAddress addrIn, bool is_inbound, bool is_manual)        : address(addrIn), m_is_inbound(is_inbound), m_is_manual_connection(is_manual)    {        fCurrentlyConnected = false;        pindexBestKnownBlock = nullptr;        hashLastUnknownBlock.SetNull();        pindexLastCommonBlock = nullptr;        pindexBestHeaderSent = nullptr;        nUnconnectingHeaders = 0;        fSyncStarted = false;        nHeadersSyncTimeout = 0;        nStallingSince = 0;        nDownloadingSince = 0;        nBlocksInFlight = 0;        nBlocksInFlightValidHeaders = 0;        fPreferredDownload = false;        fPreferHeaders = false;        fPreferHeaderAndIDs = false;        fProvidesHeaderAndIDs = false;        fHaveWitness = false;        fHaveMWEB = false;        fWantsCmpctWitness = false;        fWantsCmpctMWEB = false;        fSupportsDesiredCmpctVersion = false;        m_chain_sync = { 0, nullptr, false, false };        m_last_block_announcement = 0;        m_recently_announced_invs.reset();    }};/** Map maintaining per-node state. */static std::map<NodeId, CNodeState> mapNodeState GUARDED_BY(cs_main);static CNodeState *State(NodeId pnode) EXCLUSIVE_LOCKS_REQUIRED(cs_main) {    std::map<NodeId, CNodeState>::iterator it = mapNodeState.find(pnode);    if (it == mapNodeState.end())        return nullptr;    return &it->second;}/** * Data structure for an individual peer. This struct is not protected by * cs_main since it does not contain validation-critical data. * * Memory is owned by shared pointers and this object is destructed when * the refcount drops to zero. * * TODO: move most members from CNodeState to this structure. * TODO: move remaining application-layer data members from CNode to this structure. */struct Peer {    /** Same id as the CNode object for this peer */    const NodeId m_id{0};    /** Protects misbehavior data members */    Mutex m_misbehavior_mutex;    /** Accumulated misbehavior score for this peer */    int m_misbehavior_score GUARDED_BY(m_misbehavior_mutex){0};    /** Whether this peer should be disconnected and marked as discouraged (unless it has the noban permission). */    bool m_should_discourage GUARDED_BY(m_misbehavior_mutex){false};    /** Set of txids to reconsider once their parent transactions have been accepted **/    std::set<uint256> m_orphan_work_set GUARDED_BY(g_cs_orphans);    /** Protects m_getdata_requests **/    Mutex m_getdata_requests_mutex;    /** Work queue of items requested by this peer **/    std::deque<CInv> m_getdata_requests GUARDED_BY(m_getdata_requests_mutex);    /** Number of addresses that can be processed from this peer. Start at 1 to     *  permit self-announcement. */    double m_addr_token_bucket{1.0};    /** When m_addr_token_bucket was last updated */    std::chrono::microseconds m_addr_token_timestamp{GetTime<std::chrono::microseconds>()};    /** Total number of addresses that were dropped due to rate limiting. */    std::atomic<uint64_t> m_addr_rate_limited{0};    /** Total number of addresses that were processed (excludes rate-limited ones). */    std::atomic<uint64_t> m_addr_processed{0};    Peer(NodeId id) : m_id(id) {}};using PeerRef = std::shared_ptr<Peer>;/** * Map of all Peer objects, keyed by peer id. This map is protected * by the global g_peer_mutex. Once a shared pointer reference is * taken, the lock may be released. Individual fields are protected by * their own locks. */Mutex g_peer_mutex;static std::map<NodeId, PeerRef> g_peer_map GUARDED_BY(g_peer_mutex);/** Get a shared pointer to the Peer object. *  May return nullptr if the Peer object can't be found. */static PeerRef GetPeerRef(NodeId id){    LOCK(g_peer_mutex);    auto it = g_peer_map.find(id);    return it != g_peer_map.end() ? it->second : nullptr;}static void UpdatePreferredDownload(const CNode& node, CNodeState* state) EXCLUSIVE_LOCKS_REQUIRED(cs_main){    nPreferredDownload -= state->fPreferredDownload;    // Whether this node should be marked as a preferred download node.    state->fPreferredDownload = (!node.IsInboundConn() || node.HasPermission(PF_NOBAN)) && !node.IsAddrFetchConn() && !node.fClient;    nPreferredDownload += state->fPreferredDownload;}static void PushNodeVersion(CNode& pnode, CConnman& connman, int64_t nTime){    // Note that pnode->GetLocalServices() is a reflection of the local    // services we were offering when the CNode object was created for this    // peer.    ServiceFlags nLocalNodeServices = pnode.GetLocalServices();    uint64_t nonce = pnode.GetLocalNonce();    int nNodeStartingHeight = pnode.GetMyStartingHeight();    NodeId nodeid = pnode.GetId();    CAddress addr = pnode.addr;    CAddress addrYou = addr.IsRoutable() && !IsProxy(addr) && addr.IsAddrV1Compatible() ?                           addr :                           CAddress(CService(), addr.nServices);    CAddress addrMe = CAddress(CService(), nLocalNodeServices);    connman.PushMessage(&pnode, CNetMsgMaker(INIT_PROTO_VERSION).Make(NetMsgType::VERSION, PROTOCOL_VERSION, (uint64_t)nLocalNodeServices, nTime, addrYou, addrMe,            nonce, strSubVersion, nNodeStartingHeight, ::g_relay_txes && pnode.m_tx_relay != nullptr));    if (fLogIPs) {        LogPrint(BCLog::NET, "send version message: version %d, blocks=%d, us=%s, them=%s, peer=%d\n", PROTOCOL_VERSION, nNodeStartingHeight, addrMe.ToString(), addrYou.ToString(), nodeid);    } else {        LogPrint(BCLog::NET, "send version message: version %d, blocks=%d, us=%s, peer=%d\n", PROTOCOL_VERSION, nNodeStartingHeight, addrMe.ToString(), nodeid);    }}// Returns a bool indicating whether we requested this block.// Also used if a block was /not/ received and timed out or started with another peerstatic bool MarkBlockAsReceived(const uint256& hash, Optional<NodeId> from_peer) EXCLUSIVE_LOCKS_REQUIRED(cs_main) {    std::map<uint256, std::pair<NodeId, std::list<QueuedBlock>::iterator> >::iterator itInFlight = mapBlocksInFlight.find(hash);    if (itInFlight != mapBlocksInFlight.end()) {        auto node_id = itInFlight->second.first;        if (from_peer && node_id != *from_peer) {            // Block was requested by another peer            return true;        }        CNodeState *state = State(itInFlight->second.first);        assert(state != nullptr);        state->nBlocksInFlightValidHeaders -= itInFlight->second.second->fValidatedHeaders;        if (state->nBlocksInFlightValidHeaders == 0 && itInFlight->second.second->fValidatedHeaders) {            // Last validated block on the queue was received.            nPeersWithValidatedDownloads--;        }        if (state->vBlocksInFlight.begin() == itInFlight->second.second) {            // First block on the queue was received, update the start download time for the next one            state->nDownloadingSince = std::max(state->nDownloadingSince, count_microseconds(GetTime<std::chrono::microseconds>()));        }        state->vBlocksInFlight.erase(itInFlight->second.second);        state->nBlocksInFlight--;        state->nStallingSince = 0;        mapBlocksInFlight.erase(itInFlight);        return true;    }    return false;}// returns false, still setting pit, if the block was already in flight from the same peer// pit will only be valid as long as the same cs_main lock is being heldstatic bool MarkBlockAsInFlight(CTxMemPool& mempool, NodeId nodeid, const uint256& hash, const CBlockIndex* pindex = nullptr, std::list<QueuedBlock>::iterator** pit = nullptr) EXCLUSIVE_LOCKS_REQUIRED(cs_main) {    CNodeState *state = State(nodeid);    assert(state != nullptr);    // Short-circuit most stuff in case it is from the same node    std::map<uint256, std::pair<NodeId, std::list<QueuedBlock>::iterator> >::iterator itInFlight = mapBlocksInFlight.find(hash);    if (itInFlight != mapBlocksInFlight.end() && itInFlight->second.first == nodeid) {        if (pit) {            *pit = &itInFlight->second.second;        }        return false;    }    // Make sure it's not listed somewhere already.    MarkBlockAsReceived(hash, nullopt);    MWEB::Block mweb_block;    if (pit && (*pit)) {        mweb_block = (*(*pit))->partialBlock->mweb_block;    }    std::list<QueuedBlock>::iterator it = state->vBlocksInFlight.insert(state->vBlocksInFlight.end(),            {hash, pindex, pindex != nullptr, std::unique_ptr<PartiallyDownloadedBlock>(pit ? new PartiallyDownloadedBlock(&mempool, mweb_block) : nullptr)});    state->nBlocksInFlight++;    state->nBlocksInFlightValidHeaders += it->fValidatedHeaders;    if (state->nBlocksInFlight == 1) {        // We're starting a block download (batch) from this peer.        state->nDownloadingSince = GetTime<std::chrono::microseconds>().count();    }    if (state->nBlocksInFlightValidHeaders == 1 && pindex != nullptr) {        nPeersWithValidatedDownloads++;    }    itInFlight = mapBlocksInFlight.insert(std::make_pair(hash, std::make_pair(nodeid, it))).first;    if (pit)        *pit = &itInFlight->second.second;    return true;}/** Check whether the last unknown block a peer advertised is not yet known. */static void ProcessBlockAvailability(NodeId nodeid) EXCLUSIVE_LOCKS_REQUIRED(cs_main) {    CNodeState *state = State(nodeid);    assert(state != nullptr);    if (!state->hashLastUnknownBlock.IsNull()) {        const CBlockIndex* pindex = LookupBlockIndex(state->hashLastUnknownBlock);        if (pindex && pindex->nChainWork > 0) {            if (state->pindexBestKnownBlock == nullptr || pindex->nChainWork >= state->pindexBestKnownBlock->nChainWork) {                state->pindexBestKnownBlock = pindex;            }            state->hashLastUnknownBlock.SetNull();        }    }}/** Update tracking information about which blocks a peer is assumed to have. */static void UpdateBlockAvailability(NodeId nodeid, const uint256 &hash) EXCLUSIVE_LOCKS_REQUIRED(cs_main) {    CNodeState *state = State(nodeid);    assert(state != nullptr);    ProcessBlockAvailability(nodeid);    const CBlockIndex* pindex = LookupBlockIndex(hash);    if (pindex && pindex->nChainWork > 0) {        // An actually better block was announced.        if (state->pindexBestKnownBlock == nullptr || pindex->nChainWork >= state->pindexBestKnownBlock->nChainWork) {            state->pindexBestKnownBlock = pindex;        }    } else {        // An unknown block was announced; just assume that the latest one is the best one.        state->hashLastUnknownBlock = hash;    }}/** * When a peer sends us a valid block, instruct it to announce blocks to us * using CMPCTBLOCK if possible by adding its nodeid to the end of * lNodesAnnouncingHeaderAndIDs, and keeping that list under a certain size by * removing the first element if necessary. */static void MaybeSetPeerAsAnnouncingHeaderAndIDs(NodeId nodeid, CConnman& connman) EXCLUSIVE_LOCKS_REQUIRED(cs_main){    AssertLockHeld(cs_main);    CNodeState* nodestate = State(nodeid);    if (!nodestate || !nodestate->fSupportsDesiredCmpctVersion) {        // Never ask from peers who can't provide witnesses.        return;    }    if (nodestate->fProvidesHeaderAndIDs) {        for (std::list<NodeId>::iterator it = lNodesAnnouncingHeaderAndIDs.begin(); it != lNodesAnnouncingHeaderAndIDs.end(); it++) {            if (*it == nodeid) {                lNodesAnnouncingHeaderAndIDs.erase(it);                lNodesAnnouncingHeaderAndIDs.push_back(nodeid);                return;            }        }        connman.ForNode(nodeid, [&connman](CNode* pfrom) EXCLUSIVE_LOCKS_REQUIRED(::cs_main) {            AssertLockHeld(::cs_main);            uint64_t nCMPCTBLOCKVersion = State(pfrom->GetId())->GetCmpctBlockVersion();            if (lNodesAnnouncingHeaderAndIDs.size() >= 3) {                // As per BIP152, we only get 3 of our peers to announce                // blocks using compact encodings.                connman.ForNode(lNodesAnnouncingHeaderAndIDs.front(), [&connman, nCMPCTBLOCKVersion](CNode* pnodeStop){                    connman.PushMessage(pnodeStop, CNetMsgMaker(pnodeStop->GetCommonVersion()).Make(NetMsgType::SENDCMPCT, /*fAnnounceUsingCMPCTBLOCK=*/false, nCMPCTBLOCKVersion));                    return true;                });                lNodesAnnouncingHeaderAndIDs.pop_front();            }            connman.PushMessage(pfrom, CNetMsgMaker(pfrom->GetCommonVersion()).Make(NetMsgType::SENDCMPCT, /*fAnnounceUsingCMPCTBLOCK=*/true, nCMPCTBLOCKVersion));            lNodesAnnouncingHeaderAndIDs.push_back(pfrom->GetId());            return true;        });    }}static bool TipMayBeStale(const Consensus::Params &consensusParams) EXCLUSIVE_LOCKS_REQUIRED(cs_main){    AssertLockHeld(cs_main);    if (g_last_tip_update == 0) {        g_last_tip_update = GetTime();    }    return g_last_tip_update < GetTime() - consensusParams.nPowTargetSpacing * 3 && mapBlocksInFlight.empty();}static bool CanDirectFetch(const Consensus::Params &consensusParams) EXCLUSIVE_LOCKS_REQUIRED(cs_main){    return ::ChainActive().Tip()->GetBlockTime() > GetAdjustedTime() - consensusParams.nPowTargetSpacing * 20;}static bool PeerHasHeader(CNodeState *state, const CBlockIndex *pindex) EXCLUSIVE_LOCKS_REQUIRED(cs_main){    if (state->pindexBestKnownBlock && pindex == state->pindexBestKnownBlock->GetAncestor(pindex->nHeight))        return true;    if (state->pindexBestHeaderSent && pindex == state->pindexBestHeaderSent->GetAncestor(pindex->nHeight))        return true;    return false;}/** Update pindexLastCommonBlock and add not-in-flight missing successors to vBlocks, until it has *  at most count entries. */static void FindNextBlocksToDownload(NodeId nodeid, unsigned int count, std::vector<const CBlockIndex*>& vBlocks, NodeId& nodeStaller, const Consensus::Params& consensusParams) EXCLUSIVE_LOCKS_REQUIRED(cs_main){    if (count == 0)        return;    vBlocks.reserve(vBlocks.size() + count);    CNodeState *state = State(nodeid);    assert(state != nullptr);    // Make sure pindexBestKnownBlock is up to date, we'll need it.    ProcessBlockAvailability(nodeid);    if (state->pindexBestKnownBlock == nullptr || state->pindexBestKnownBlock->nChainWork < ::ChainActive().Tip()->nChainWork || state->pindexBestKnownBlock->nChainWork < nMinimumChainWork) {        // This peer has nothing interesting.        return;    }    if (state->pindexLastCommonBlock == nullptr) {        // Bootstrap quickly by guessing a parent of our best tip is the forking point.        // Guessing wrong in either direction is not a problem.        state->pindexLastCommonBlock = ::ChainActive()[std::min(state->pindexBestKnownBlock->nHeight, ::ChainActive().Height())];    }    // If the peer reorganized, our previous pindexLastCommonBlock may not be an ancestor    // of its current tip anymore. Go back enough to fix that.    state->pindexLastCommonBlock = LastCommonAncestor(state->pindexLastCommonBlock, state->pindexBestKnownBlock);    if (state->pindexLastCommonBlock == state->pindexBestKnownBlock)        return;    std::vector<const CBlockIndex*> vToFetch;    const CBlockIndex *pindexWalk = state->pindexLastCommonBlock;    // Never fetch further than the best block we know the peer has, or more than BLOCK_DOWNLOAD_WINDOW + 1 beyond the last    // linked block we have in common with this peer. The +1 is so we can detect stalling, namely if we would be able to    // download that next block if the window were 1 larger.    int nWindowEnd = state->pindexLastCommonBlock->nHeight + BLOCK_DOWNLOAD_WINDOW;    int nMaxHeight = std::min<int>(state->pindexBestKnownBlock->nHeight, nWindowEnd + 1);    NodeId waitingfor = -1;    while (pindexWalk->nHeight < nMaxHeight) {        // Read up to 128 (or more, if more blocks than that are needed) successors of pindexWalk (towards        // pindexBestKnownBlock) into vToFetch. We fetch 128, because CBlockIndex::GetAncestor may be as expensive        // as iterating over ~100 CBlockIndex* entries anyway.        int nToFetch = std::min(nMaxHeight - pindexWalk->nHeight, std::max<int>(count - vBlocks.size(), 128));        vToFetch.resize(nToFetch);        pindexWalk = state->pindexBestKnownBlock->GetAncestor(pindexWalk->nHeight + nToFetch);        vToFetch[nToFetch - 1] = pindexWalk;        for (unsigned int i = nToFetch - 1; i > 0; i--) {            vToFetch[i - 1] = vToFetch[i]->pprev;        }        // Iterate over those blocks in vToFetch (in forward direction), adding the ones that        // are not yet downloaded and not in flight to vBlocks. In the meantime, update        // pindexLastCommonBlock as long as all ancestors are already downloaded, or if it's        // already part of our chain (and therefore don't need it even if pruned).        for (const CBlockIndex* pindex : vToFetch) {            if (!pindex->IsValid(BLOCK_VALID_TREE)) {                // We consider the chain that this peer is on invalid.                return;            }            if (!State(nodeid)->fHaveWitness && IsWitnessEnabled(pindex->pprev, consensusParams)) {                // We wouldn't download this block or its descendants from this peer.                return;            }            if (!State(nodeid)->fHaveMWEB && IsMWEBEnabled(pindex->pprev, consensusParams)) {                // MWEB: Can't download this block from this peer.                return;            }            if (pindex->nStatus & BLOCK_HAVE_DATA || ::ChainActive().Contains(pindex)) {                if (pindex->HaveTxsDownloaded())                    state->pindexLastCommonBlock = pindex;            } else if (mapBlocksInFlight.count(pindex->GetBlockHash()) == 0) {                // The block is not already downloaded, and not yet in flight.                if (pindex->nHeight > nWindowEnd) {                    // We reached the end of the window.                    if (vBlocks.size() == 0 && waitingfor != nodeid) {                        // We aren't able to fetch anything, but we would be if the download window was one larger.                        nodeStaller = waitingfor;                    }                    return;                }                vBlocks.push_back(pindex);                if (vBlocks.size() == count) {                    return;                }            } else if (waitingfor == -1) {                // This is the first already-in-flight block.                waitingfor = mapBlocksInFlight[pindex->GetBlockHash()].first;            }        }    }}} // namespacevoid PeerManager::AddTxAnnouncement(const CNode& node, const GenTxid& gtxid, std::chrono::microseconds current_time){    AssertLockHeld(::cs_main); // For m_txrequest    NodeId nodeid = node.GetId();    if (!node.HasPermission(PF_RELAY) && m_txrequest.Count(nodeid) >= MAX_PEER_TX_ANNOUNCEMENTS) {        // Too many queued announcements from this peer        return;    }    const CNodeState* state = State(nodeid);    // Decide the TxRequestTracker parameters for this announcement:    // - "preferred": if fPreferredDownload is set (= outbound, or PF_NOBAN permission)    // - "reqtime": current time plus delays for:    //   - NONPREF_PEER_TX_DELAY for announcements from non-preferred connections    //   - TXID_RELAY_DELAY for txid announcements while wtxid peers are available    //   - OVERLOADED_PEER_TX_DELAY for announcements from peers which have at least    //     MAX_PEER_TX_REQUEST_IN_FLIGHT requests in flight (and don't have PF_RELAY).    auto delay = std::chrono::microseconds{0};    const bool preferred = state->fPreferredDownload;    if (!preferred) delay += NONPREF_PEER_TX_DELAY;    if (!gtxid.IsWtxid() && g_wtxid_relay_peers > 0) delay += TXID_RELAY_DELAY;    const bool overloaded = !node.HasPermission(PF_RELAY) &&        m_txrequest.CountInFlight(nodeid) >= MAX_PEER_TX_REQUEST_IN_FLIGHT;    if (overloaded) delay += OVERLOADED_PEER_TX_DELAY;    m_txrequest.ReceivedInv(nodeid, gtxid, preferred, current_time + delay);}// This function is used for testing the stale tip eviction logic, see// denialofservice_tests.cppvoid UpdateLastBlockAnnounceTime(NodeId node, int64_t time_in_seconds){    LOCK(cs_main);    CNodeState *state = State(node);    if (state) state->m_last_block_announcement = time_in_seconds;}void PeerManager::InitializeNode(CNode *pnode) {    CAddress addr = pnode->addr;    std::string addrName = pnode->GetAddrName();    NodeId nodeid = pnode->GetId();    {        LOCK(cs_main);        mapNodeState.emplace_hint(mapNodeState.end(), std::piecewise_construct, std::forward_as_tuple(nodeid), std::forward_as_tuple(addr, pnode->IsInboundConn(), pnode->IsManualConn()));        assert(m_txrequest.Count(nodeid) == 0);    }    {        PeerRef peer = std::make_shared<Peer>(nodeid);        LOCK(g_peer_mutex);        g_peer_map.emplace_hint(g_peer_map.end(), nodeid, std::move(peer));    }    if (!pnode->IsInboundConn()) {        PushNodeVersion(*pnode, m_connman, GetTime());    }}void PeerManager::ReattemptInitialBroadcast(CScheduler& scheduler) const{    std::set<uint256> unbroadcast_txids = m_mempool.GetUnbroadcastTxs();    for (const auto& txid : unbroadcast_txids) {        CTransactionRef tx = m_mempool.get(txid);        if (tx != nullptr) {            LOCK(cs_main);            RelayTransaction(txid, tx->GetWitnessHash(), m_connman);        } else {            m_mempool.RemoveUnbroadcastTx(txid, true);        }    }    // Schedule next run for 10-15 minutes in the future.    // We add randomness on every cycle to avoid the possibility of P2P fingerprinting.    const std::chrono::milliseconds delta = std::chrono::minutes{10} + GetRandMillis(std::chrono::minutes{5});    scheduler.scheduleFromNow([&] { ReattemptInitialBroadcast(scheduler); }, delta);}void PeerManager::FinalizeNode(const CNode& node, bool& fUpdateConnectionTime) {    NodeId nodeid = node.GetId();    fUpdateConnectionTime = false;    LOCK(cs_main);    int misbehavior{0};    {        PeerRef peer = GetPeerRef(nodeid);        assert(peer != nullptr);        misbehavior = WITH_LOCK(peer->m_misbehavior_mutex, return peer->m_misbehavior_score);        LOCK(g_peer_mutex);        g_peer_map.erase(nodeid);    }    CNodeState *state = State(nodeid);    assert(state != nullptr);    if (state->fSyncStarted)        nSyncStarted--;    if (misbehavior == 0 && state->fCurrentlyConnected && !node.IsBlockOnlyConn()) {        // Note: we avoid changing visible addrman state for block-relay-only peers        fUpdateConnectionTime = true;    }    for (const QueuedBlock& entry : state->vBlocksInFlight) {        mapBlocksInFlight.erase(entry.hash);    }    EraseOrphansFor(nodeid);    m_txrequest.DisconnectedPeer(nodeid);    nPreferredDownload -= state->fPreferredDownload;    nPeersWithValidatedDownloads -= (state->nBlocksInFlightValidHeaders != 0);    assert(nPeersWithValidatedDownloads >= 0);    g_outbound_peers_with_protect_from_disconnect -= state->m_chain_sync.m_protect;    assert(g_outbound_peers_with_protect_from_disconnect >= 0);    g_wtxid_relay_peers -= state->m_wtxid_relay;    assert(g_wtxid_relay_peers >= 0);    mapNodeState.erase(nodeid);    if (mapNodeState.empty()) {        // Do a consistency check after the last peer is removed.        assert(mapBlocksInFlight.empty());        assert(nPreferredDownload == 0);        assert(nPeersWithValidatedDownloads == 0);        assert(g_outbound_peers_with_protect_from_disconnect == 0);        assert(g_wtxid_relay_peers == 0);        assert(m_txrequest.Size() == 0);    }    LogPrint(BCLog::NET, "Cleared nodestate for peer=%d\n", nodeid);}bool GetNodeStateStats(NodeId nodeid, CNodeStateStats &stats) {    {        LOCK(cs_main);        CNodeState* state = State(nodeid);        if (state == nullptr)            return false;        stats.nSyncHeight = state->pindexBestKnownBlock ? state->pindexBestKnownBlock->nHeight : -1;        stats.nCommonHeight = state->pindexLastCommonBlock ? state->pindexLastCommonBlock->nHeight : -1;        for (const QueuedBlock& queue : state->vBlocksInFlight) {            if (queue.pindex)                stats.vHeightInFlight.push_back(queue.pindex->nHeight);        }    }    PeerRef peer = GetPeerRef(nodeid);    if (peer == nullptr) return false;    stats.m_misbehavior_score = WITH_LOCK(peer->m_misbehavior_mutex, return peer->m_misbehavior_score);    stats.m_addr_processed = peer->m_addr_processed.load();    stats.m_addr_rate_limited = peer->m_addr_rate_limited.load();    return true;}////////////////////////////////////////////////////////////////////////////////// mapOrphanTransactions//static void AddToCompactExtraTransactions(const CTransactionRef& tx) EXCLUSIVE_LOCKS_REQUIRED(g_cs_orphans){    size_t max_extra_txn = gArgs.GetArg("-blockreconstructionextratxn", DEFAULT_BLOCK_RECONSTRUCTION_EXTRA_TXN);    if (max_extra_txn <= 0)        return;    if (!vExtraTxnForCompact.size())        vExtraTxnForCompact.resize(max_extra_txn);    vExtraTxnForCompact[vExtraTxnForCompactIt] = std::make_pair(tx->GetWitnessHash(), tx);    vExtraTxnForCompactIt = (vExtraTxnForCompactIt + 1) % max_extra_txn;}bool AddOrphanTx(const CTransactionRef& tx, NodeId peer) EXCLUSIVE_LOCKS_REQUIRED(g_cs_orphans){    const uint256& hash = tx->GetHash();    if (mapOrphanTransactions.count(hash))        return false;    // Ignore big transactions, to avoid a    // send-big-orphans memory exhaustion attack. If a peer has a legitimate    // large transaction with a missing parent then we assume    // it will rebroadcast it later, after the parent transaction(s)    // have been mined or received.    // 100 orphans, each of which is at most 100,000 bytes big is    // at most 10 megabytes of orphans and somewhat more byprev index (in the worst case):    unsigned int sz = GetTransactionWeight(*tx);    if (sz > MAX_STANDARD_TX_WEIGHT)    {        LogPrint(BCLog::MEMPOOL, "ignoring large orphan tx (size: %u, hash: %s)\n", sz, hash.ToString());        return false;    }    auto ret = mapOrphanTransactions.emplace(hash, COrphanTx{tx, peer, GetTime() + ORPHAN_TX_EXPIRE_TIME, g_orphan_list.size()});    assert(ret.second);    g_orphan_list.push_back(ret.first);    // Allow for lookups in the orphan pool by wtxid, as well as txid    g_orphans_by_wtxid.emplace(tx->GetWitnessHash(), ret.first);    for (const CTxIn& txin : tx->vin) {        mapOrphanTransactionsByPrev[txin.prevout].insert(ret.first);    }    AddToCompactExtraTransactions(tx);    LogPrint(BCLog::MEMPOOL, "stored orphan tx %s (mapsz %u outsz %u)\n", hash.ToString(),             mapOrphanTransactions.size(), mapOrphanTransactionsByPrev.size());    return true;}int static EraseOrphanTx(uint256 hash) EXCLUSIVE_LOCKS_REQUIRED(g_cs_orphans){    std::map<uint256, COrphanTx>::iterator it = mapOrphanTransactions.find(hash);    if (it == mapOrphanTransactions.end())        return 0;    for (const CTxIn& txin : it->second.tx->vin)    {        auto itPrev = mapOrphanTransactionsByPrev.find(txin.prevout);        if (itPrev == mapOrphanTransactionsByPrev.end())            continue;        itPrev->second.erase(it);        if (itPrev->second.empty())            mapOrphanTransactionsByPrev.erase(itPrev);    }    size_t old_pos = it->second.list_pos;    assert(g_orphan_list[old_pos] == it);    if (old_pos + 1 != g_orphan_list.size()) {        // Unless we're deleting the last entry in g_orphan_list, move the last        // entry to the position we're deleting.        auto it_last = g_orphan_list.back();        g_orphan_list[old_pos] = it_last;        it_last->second.list_pos = old_pos;    }    g_orphan_list.pop_back();    g_orphans_by_wtxid.erase(it->second.tx->GetWitnessHash());    mapOrphanTransactions.erase(it);    return 1;}void EraseOrphansFor(NodeId peer){    LOCK(g_cs_orphans);    int nErased = 0;    std::map<uint256, COrphanTx>::iterator iter = mapOrphanTransactions.begin();    while (iter != mapOrphanTransactions.end())    {        std::map<uint256, COrphanTx>::iterator maybeErase = iter++; // increment to avoid iterator becoming invalid        if (maybeErase->second.fromPeer == peer)        {            nErased += EraseOrphanTx(maybeErase->second.tx->GetHash());        }    }    if (nErased > 0) LogPrint(BCLog::MEMPOOL, "Erased %d orphan tx from peer=%d\n", nErased, peer);}unsigned int LimitOrphanTxSize(unsigned int nMaxOrphans){    LOCK(g_cs_orphans);    unsigned int nEvicted = 0;    static int64_t nNextSweep;    int64_t nNow = GetTime();    if (nNextSweep <= nNow) {        // Sweep out expired orphan pool entries:        int nErased = 0;        int64_t nMinExpTime = nNow + ORPHAN_TX_EXPIRE_TIME - ORPHAN_TX_EXPIRE_INTERVAL;        std::map<uint256, COrphanTx>::iterator iter = mapOrphanTransactions.begin();        while (iter != mapOrphanTransactions.end())        {            std::map<uint256, COrphanTx>::iterator maybeErase = iter++;            if (maybeErase->second.nTimeExpire <= nNow) {                nErased += EraseOrphanTx(maybeErase->second.tx->GetHash());            } else {                nMinExpTime = std::min(maybeErase->second.nTimeExpire, nMinExpTime);            }        }        // Sweep again 5 minutes after the next entry that expires in order to batch the linear scan.        nNextSweep = nMinExpTime + ORPHAN_TX_EXPIRE_INTERVAL;        if (nErased > 0) LogPrint(BCLog::MEMPOOL, "Erased %d orphan tx due to expiration\n", nErased);    }    FastRandomContext rng;    while (mapOrphanTransactions.size() > nMaxOrphans)    {        // Evict a random orphan:        size_t randompos = rng.randrange(g_orphan_list.size());        EraseOrphanTx(g_orphan_list[randompos]->first);        ++nEvicted;    }    return nEvicted;}void PeerManager::Misbehaving(const NodeId pnode, const int howmuch, const std::string& message){    assert(howmuch > 0);    PeerRef peer = GetPeerRef(pnode);    if (peer == nullptr) return;    LOCK(peer->m_misbehavior_mutex);    peer->m_misbehavior_score += howmuch;    const std::string message_prefixed = message.empty() ? "" : (": " + message);    if (peer->m_misbehavior_score >= DISCOURAGEMENT_THRESHOLD && peer->m_misbehavior_score - howmuch < DISCOURAGEMENT_THRESHOLD) {        LogPrint(BCLog::NET, "Misbehaving: peer=%d (%d -> %d) DISCOURAGE THRESHOLD EXCEEDED%s\n", pnode, peer->m_misbehavior_score - howmuch, peer->m_misbehavior_score, message_prefixed);        peer->m_should_discourage = true;    } else {        LogPrint(BCLog::NET, "Misbehaving: peer=%d (%d -> %d)%s\n", pnode, peer->m_misbehavior_score - howmuch, peer->m_misbehavior_score, message_prefixed);    }}bool PeerManager::MaybePunishNodeForBlock(NodeId nodeid, const BlockValidationState& state,                                          bool via_compact_block, const std::string& message){    switch (state.GetResult()) {    case BlockValidationResult::BLOCK_RESULT_UNSET:        break;    // The node is providing invalid data:    case BlockValidationResult::BLOCK_CONSENSUS:    case BlockValidationResult::BLOCK_MUTATED:        if (!via_compact_block) {            Misbehaving(nodeid, 100, message);            return true;        }        break;    case BlockValidationResult::BLOCK_CACHED_INVALID:        {            LOCK(cs_main);            CNodeState *node_state = State(nodeid);            if (node_state == nullptr) {                break;            }            // Discourage outbound (but not inbound) peers if on an invalid chain.            // Exempt HB compact block peers and manual connections.            if (!via_compact_block && !node_state->m_is_inbound && !node_state->m_is_manual_connection) {                Misbehaving(nodeid, 100, message);                return true;            }            break;        }    case BlockValidationResult::BLOCK_INVALID_HEADER:    case BlockValidationResult::BLOCK_CHECKPOINT:    case BlockValidationResult::BLOCK_INVALID_PREV:        Misbehaving(nodeid, 100, message);        return true;    // Conflicting (but not necessarily invalid) data or different policy:    case BlockValidationResult::BLOCK_MISSING_PREV:        // TODO: Handle this much more gracefully (10 DoS points is super arbitrary)        Misbehaving(nodeid, 10, message);        return true;    case BlockValidationResult::BLOCK_RECENT_CONSENSUS_CHANGE:    case BlockValidationResult::BLOCK_TIME_FUTURE:        break;    }    if (message != "") {        LogPrint(BCLog::NET, "peer=%d: %s\n", nodeid, message);    }    return false;}bool PeerManager::MaybePunishNodeForTx(NodeId nodeid, const TxValidationState& state, const std::string& message){    switch (state.GetResult()) {    case TxValidationResult::TX_RESULT_UNSET:        break;    // The node is providing invalid data:    case TxValidationResult::TX_CONSENSUS:        Misbehaving(nodeid, 100, message);        return true;    // Conflicting (but not necessarily invalid) data or different policy:    case TxValidationResult::TX_RECENT_CONSENSUS_CHANGE:    case TxValidationResult::TX_INPUTS_NOT_STANDARD:    case TxValidationResult::TX_NOT_STANDARD:    case TxValidationResult::TX_MISSING_INPUTS:    case TxValidationResult::TX_PREMATURE_SPEND:    case TxValidationResult::TX_WITNESS_MUTATED:    case TxValidationResult::TX_WITNESS_STRIPPED:    case TxValidationResult::TX_CONFLICT:    case TxValidationResult::TX_MEMPOOL_POLICY:        break;    }    if (message != "") {        LogPrint(BCLog::NET, "peer=%d: %s\n", nodeid, message);    }    return false;}////////////////////////////////////////////////////////////////////////////////// blockchain -> download logic notification//// To prevent fingerprinting attacks, only send blocks/headers outside of the// active chain if they are no more than a month older (both in time, and in// best equivalent proof of work) than the best header chain we know about and// we fully-validated them at some point.static bool BlockRequestAllowed(const CBlockIndex* pindex, const Consensus::Params& consensusParams) EXCLUSIVE_LOCKS_REQUIRED(cs_main){    AssertLockHeld(cs_main);    if (::ChainActive().Contains(pindex)) return true;    return pindex->IsValid(BLOCK_VALID_SCRIPTS) && (pindexBestHeader != nullptr) &&        (pindexBestHeader->GetBlockTime() - pindex->GetBlockTime() < STALE_RELAY_AGE_LIMIT) &&        (GetBlockProofEquivalentTime(*pindexBestHeader, *pindex, *pindexBestHeader, consensusParams) < STALE_RELAY_AGE_LIMIT);}PeerManager::PeerManager(const CChainParams& chainparams, CConnman& connman, BanMan* banman,                         CScheduler& scheduler, ChainstateManager& chainman, CTxMemPool& pool)    : m_chainparams(chainparams),      m_connman(connman),      m_banman(banman),      m_chainman(chainman),      m_mempool(pool),      m_stale_tip_check_time(0){    // Initialize global variables that cannot be constructed at startup.    recentRejects.reset(new CRollingBloomFilter(120000, 0.000001));    // Blocks don't typically have more than 4000 transactions, so this should    // be at least six blocks (~1 hr) worth of transactions that we can store,    // inserting both a txid and wtxid for every observed transaction.    // If the number of transactions appearing in a block goes up, or if we are    // seeing getdata requests more than an hour after initial announcement, we    // can increase this number.    // The false positive rate of 1/1M should come out to less than 1    // transaction per day that would be inadvertently ignored (which is the    // same probability that we have in the reject filter).    g_recent_confirmed_transactions.reset(new CRollingBloomFilter(48000, 0.000001));    // Stale tip checking and peer eviction are on two different timers, but we    // don't want them to get out of sync due to drift in the scheduler, so we    // combine them in one function and schedule at the quicker (peer-eviction)    // timer.    static_assert(EXTRA_PEER_CHECK_INTERVAL < STALE_CHECK_INTERVAL, "peer eviction timer should be less than stale tip check timer");    scheduler.scheduleEvery([this] { this->CheckForStaleTipAndEvictPeers(); }, std::chrono::seconds{EXTRA_PEER_CHECK_INTERVAL});    // schedule next run for 10-15 minutes in the future    const std::chrono::milliseconds delta = std::chrono::minutes{10} + GetRandMillis(std::chrono::minutes{5});    scheduler.scheduleFromNow([&] { ReattemptInitialBroadcast(scheduler); }, delta);}/** * Evict orphan txn pool entries (EraseOrphanTx) based on a newly connected * block, remember the recently confirmed transactions, and delete tracked * announcements for them. Also save the time of the last tip update. */void PeerManager::BlockConnected(const std::shared_ptr<const CBlock>& pblock, const CBlockIndex* pindex){    {        LOCK(g_cs_orphans);        std::vector<uint256> vOrphanErase;        for (const CTransactionRef& ptx : pblock->vtx) {            const CTransaction& tx = *ptx;            // Which orphan pool entries must we evict?            for (const auto& txin : tx.vin) {                auto itByPrev = mapOrphanTransactionsByPrev.find(txin.prevout);                if (itByPrev == mapOrphanTransactionsByPrev.end()) continue;                for (auto mi = itByPrev->second.begin(); mi != itByPrev->second.end(); ++mi) {                    const CTransaction& orphanTx = *(*mi)->second.tx;                    const uint256& orphanHash = orphanTx.GetHash();                    vOrphanErase.push_back(orphanHash);                }            }        }        // Erase orphan transactions included or precluded by this block        if (vOrphanErase.size()) {            int nErased = 0;            for (const uint256& orphanHash : vOrphanErase) {                nErased += EraseOrphanTx(orphanHash);            }            LogPrint(BCLog::MEMPOOL, "Erased %d orphan tx included or conflicted by block\n", nErased);        }        g_last_tip_update = GetTime();    }    {        LOCK(g_cs_recent_confirmed_transactions);        for (const auto& ptx : pblock->vtx) {            g_recent_confirmed_transactions->insert(ptx->GetHash());            if (ptx->GetHash() != ptx->GetWitnessHash()) {                g_recent_confirmed_transactions->insert(ptx->GetWitnessHash());            }        }    }    {        LOCK(cs_main);        for (const auto& ptx : pblock->vtx) {            m_txrequest.ForgetTxHash(ptx->GetHash());            m_txrequest.ForgetTxHash(ptx->GetWitnessHash());        }    }}void PeerManager::BlockDisconnected(const std::shared_ptr<const CBlock> &block, const CBlockIndex* pindex){    // To avoid relay problems with transactions that were previously    // confirmed, clear our filter of recently confirmed transactions whenever    // there's a reorg.    // This means that in a 1-block reorg (where 1 block is disconnected and    // then another block reconnected), our filter will drop to having only one    // block's worth of transactions in it, but that should be fine, since    // presumably the most common case of relaying a confirmed transaction    // should be just after a new block containing it is found.    LOCK(g_cs_recent_confirmed_transactions);    g_recent_confirmed_transactions->reset();}// All of the following cache a recent block, and are protected by cs_most_recent_blockstatic RecursiveMutex cs_most_recent_block;static std::shared_ptr<const CBlock> most_recent_block GUARDED_BY(cs_most_recent_block);static std::shared_ptr<const CBlockHeaderAndShortTxIDs> most_recent_compact_block GUARDED_BY(cs_most_recent_block);static uint256 most_recent_block_hash GUARDED_BY(cs_most_recent_block);static bool fWitnessesPresentInMostRecentCompactBlock GUARDED_BY(cs_most_recent_block);static bool fMWEBPresentInMostRecentCompactBlock GUARDED_BY(cs_most_recent_block);/** * Maintain state about the best-seen block and fast-announce a compact block * to compatible peers. */void PeerManager::NewPoWValidBlock(const CBlockIndex *pindex, const std::shared_ptr<const CBlock>& pblock) {    std::shared_ptr<const CBlockHeaderAndShortTxIDs> pcmpctblock = std::make_shared<const CBlockHeaderAndShortTxIDs> (*pblock, true);    const CNetMsgMaker msgMaker(PROTOCOL_VERSION);    LOCK(cs_main);    static int nHighestFastAnnounce = 0;    if (pindex->nHeight <= nHighestFastAnnounce)        return;    nHighestFastAnnounce = pindex->nHeight;    bool fWitnessEnabled = IsWitnessEnabled(pindex->pprev, m_chainparams.GetConsensus());    bool mweb_enabled = IsMWEBEnabled(pindex->pprev, m_chainparams.GetConsensus());    uint256 hashBlock(pblock->GetHash());    {        LOCK(cs_most_recent_block);        most_recent_block_hash = hashBlock;        most_recent_block = pblock;        most_recent_compact_block = pcmpctblock;        fWitnessesPresentInMostRecentCompactBlock = fWitnessEnabled;        fMWEBPresentInMostRecentCompactBlock = mweb_enabled;    }    m_connman.ForEachNode([this, &pcmpctblock, pindex, &msgMaker, fWitnessEnabled, mweb_enabled, &hashBlock](CNode* pnode) EXCLUSIVE_LOCKS_REQUIRED(::cs_main) {        AssertLockHeld(::cs_main);        // TODO: Avoid the repeated-serialization here        if (pnode->GetCommonVersion() < INVALID_CB_NO_BAN_VERSION || pnode->fDisconnect)            return;        ProcessBlockAvailability(pnode->GetId());        CNodeState &state = *State(pnode->GetId());        // If the peer has, or we announced to them the previous block already,        // but we don't think they have this one, go ahead and announce it        if (state.fPreferHeaderAndIDs && (!fWitnessEnabled || state.fWantsCmpctWitness) &&                (!mweb_enabled || state.fWantsCmpctMWEB) &&                !PeerHasHeader(&state, pindex) && PeerHasHeader(&state, pindex->pprev)) {            bool fPeerWantsWitness = State(pnode->GetId())->fWantsCmpctWitness;            bool fPeerWantsMWEB = State(pnode->GetId())->fWantsCmpctMWEB;            int nSendFlags = fPeerWantsWitness ? 0 : SERIALIZE_TRANSACTION_NO_WITNESS;            nSendFlags |= fPeerWantsMWEB ? 0 : SERIALIZE_NO_MWEB;            LogPrint(BCLog::NET, "%s sending header-and-ids %s to peer=%d\n", "PeerManager::NewPoWValidBlock",                    hashBlock.ToString(), pnode->GetId());            m_connman.PushMessage(pnode, msgMaker.Make(nSendFlags, NetMsgType::CMPCTBLOCK, *pcmpctblock));            state.pindexBestHeaderSent = pindex;        }    });}/** * Update our best height and announce any block hashes which weren't previously * in ::ChainActive() to our peers. */void PeerManager::UpdatedBlockTip(const CBlockIndex *pindexNew, const CBlockIndex *pindexFork, bool fInitialDownload) {    const int nNewHeight = pindexNew->nHeight;    m_connman.SetBestHeight(nNewHeight);    SetServiceFlagsIBDCache(!fInitialDownload);    if (!fInitialDownload) {        // Find the hashes of all blocks that weren't previously in the best chain.        std::vector<uint256> vHashes;        const CBlockIndex *pindexToAnnounce = pindexNew;        while (pindexToAnnounce != pindexFork) {            vHashes.push_back(pindexToAnnounce->GetBlockHash());            pindexToAnnounce = pindexToAnnounce->pprev;            if (vHashes.size() == MAX_BLOCKS_TO_ANNOUNCE) {                // Limit announcements in case of a huge reorganization.                // Rely on the peer's synchronization mechanism in that case.                break;            }        }        // Relay inventory, but don't relay old inventory during initial block download.        m_connman.ForEachNode([nNewHeight, &vHashes](CNode* pnode) {            LOCK(pnode->cs_inventory);            if (nNewHeight > (pnode->nStartingHeight != -1 ? pnode->nStartingHeight - 2000 : 0)) {                for (const uint256& hash : reverse_iterate(vHashes)) {                    pnode->vBlockHashesToAnnounce.push_back(hash);                }            }        });        m_connman.WakeMessageHandler();    }}/** * Handle invalid block rejection and consequent peer discouragement, maintain which * peers announce compact blocks. */void PeerManager::BlockChecked(const CBlock& block, const BlockValidationState& state) {    LOCK(cs_main);    const uint256 hash(block.GetHash());    std::map<uint256, std::pair<NodeId, bool>>::iterator it = mapBlockSource.find(hash);    // If the block failed validation, we know where it came from and we're still connected    // to that peer, maybe punish.    if (state.IsInvalid() &&        it != mapBlockSource.end() &&        State(it->second.first)) {            MaybePunishNodeForBlock(/*nodeid=*/ it->second.first, state, /*via_compact_block=*/ !it->second.second);    }    // Check that:    // 1. The block is valid    // 2. We're not in initial block download    // 3. This is currently the best block we're aware of. We haven't updated    //    the tip yet so we have no way to check this directly here. Instead we    //    just check that there are currently no other blocks in flight.    else if (state.IsValid() &&             !::ChainstateActive().IsInitialBlockDownload() &&             mapBlocksInFlight.count(hash) == mapBlocksInFlight.size()) {        if (it != mapBlockSource.end()) {            MaybeSetPeerAsAnnouncingHeaderAndIDs(it->second.first, m_connman);        }    }    if (it != mapBlockSource.end())        mapBlockSource.erase(it);}////////////////////////////////////////////////////////////////////////////////// Messages//bool static AlreadyHaveTx(const GenTxid& gtxid, const CTxMemPool& mempool) EXCLUSIVE_LOCKS_REQUIRED(cs_main){    assert(recentRejects);    if (::ChainActive().Tip()->GetBlockHash() != hashRecentRejectsChainTip) {        // If the chain tip has changed previously rejected transactions        // might be now valid, e.g. due to a nLockTime'd tx becoming valid,        // or a double-spend. Reset the rejects filter and give those        // txs a second chance.        hashRecentRejectsChainTip = ::ChainActive().Tip()->GetBlockHash();        recentRejects->reset();    }    const uint256& hash = gtxid.GetHash();    {        LOCK(g_cs_orphans);        if (!gtxid.IsWtxid() && mapOrphanTransactions.count(hash)) {            return true;        } else if (gtxid.IsWtxid() && g_orphans_by_wtxid.count(hash)) {            return true;        }    }    {        LOCK(g_cs_recent_confirmed_transactions);        if (g_recent_confirmed_transactions->contains(hash)) return true;    }    return recentRejects->contains(hash) || mempool.exists(gtxid);}bool static AlreadyHaveBlock(const uint256& block_hash) EXCLUSIVE_LOCKS_REQUIRED(cs_main){    return LookupBlockIndex(block_hash) != nullptr;}void RelayTransaction(const uint256& txid, const uint256& wtxid, const CConnman& connman){    connman.ForEachNode([&txid, &wtxid](CNode* pnode) EXCLUSIVE_LOCKS_REQUIRED(::cs_main) {        AssertLockHeld(::cs_main);        CNodeState* state = State(pnode->GetId());        if (state == nullptr) return;        if (state->m_wtxid_relay) {            pnode->PushTxInventory(wtxid);        } else {            pnode->PushTxInventory(txid);        }    });}static void RelayAddress(const CAddress& addr, bool fReachable, const CConnman& connman){    if (!fReachable && !addr.IsRelayable()) return;    // Relay to a limited number of other nodes    // Use deterministic randomness to send to the same nodes for 24 hours    // at a time so the m_addr_knowns of the chosen nodes prevent repeats    uint64_t hashAddr = addr.GetHash();    const CSipHasher hasher = connman.GetDeterministicRandomizer(RANDOMIZER_ID_ADDRESS_RELAY).Write(hashAddr << 32).Write((GetTime() + hashAddr) / (24 * 60 * 60));    FastRandomContext insecure_rand;    // Relay reachable addresses to 2 peers. Unreachable addresses are relayed randomly to 1 or 2 peers.    unsigned int nRelayNodes = (fReachable || (hasher.Finalize() & 1)) ? 2 : 1;    std::array<std::pair<uint64_t, CNode*>,2> best{{{0, nullptr}, {0, nullptr}}};    assert(nRelayNodes <= best.size());    auto sortfunc = [&best, &hasher, nRelayNodes](CNode* pnode) {        if (pnode->RelayAddrsWithConn()) {            uint64_t hashKey = CSipHasher(hasher).Write(pnode->GetId()).Finalize();            for (unsigned int i = 0; i < nRelayNodes; i++) {                 if (hashKey > best[i].first) {                     std::copy(best.begin() + i, best.begin() + nRelayNodes - 1, best.begin() + i + 1);                     best[i] = std::make_pair(hashKey, pnode);                     break;                 }            }        }    };    auto pushfunc = [&addr, &best, nRelayNodes, &insecure_rand] {        for (unsigned int i = 0; i < nRelayNodes && best[i].first != 0; i++) {            best[i].second->PushAddress(addr, insecure_rand);        }    };    connman.ForEachNodeThen(std::move(sortfunc), std::move(pushfunc));}static void ActivateBestChainIfNeeded(const CChainParams& chainparams, const CInv& inv){    bool need_activate_chain = false;    {        LOCK(cs_main);        const CBlockIndex* pindex = LookupBlockIndex(inv.hash);        if (pindex) {            if (pindex->HaveTxsDownloaded() && !pindex->IsValid(BLOCK_VALID_SCRIPTS) &&                    pindex->IsValid(BLOCK_VALID_TREE)) {                // If we have the block and all of its parents, but have not yet validated it,                // we might be in the middle of connecting it (ie in the unlock of cs_main                // before ActivateBestChain but after AcceptBlock).                // In this case, we need to run ActivateBestChain prior to checking the relay                // conditions below.                need_activate_chain = true;            }        }    } // release cs_main before calling ActivateBestChain    if (need_activate_chain) {        // Grab the current most_recent_block and pass it to ActivateBestChain        // which hopefully will prevent needing to load blocks from disk.        std::shared_ptr<const CBlock> a_recent_block;        {            LOCK(cs_most_recent_block);            a_recent_block = most_recent_block;        }        BlockValidationState state;        if (!ActivateBestChain(state, chainparams, a_recent_block)) {            LogPrint(BCLog::NET, "failed to activate chain (%s)\n", state.ToString());        }    }}void static ProcessGetBlockData(CNode& pfrom, const CChainParams& chainparams, const CInv& inv, CConnman& connman){    bool send = false;    std::shared_ptr<const CBlock> a_recent_block;    std::shared_ptr<const CBlockHeaderAndShortTxIDs> a_recent_compact_block;    bool fWitnessesPresentInARecentCompactBlock;    bool fMWEBPresentInARecentCompactBlock;    const Consensus::Params& consensusParams = chainparams.GetConsensus();    {        LOCK(cs_most_recent_block);        a_recent_block = most_recent_block;        a_recent_compact_block = most_recent_compact_block;        fWitnessesPresentInARecentCompactBlock = fWitnessesPresentInMostRecentCompactBlock;        fMWEBPresentInARecentCompactBlock = fMWEBPresentInMostRecentCompactBlock;    }    ActivateBestChainIfNeeded(chainparams, inv);    LOCK(cs_main);    const CBlockIndex* pindex = LookupBlockIndex(inv.hash);    if (pindex) {        send = BlockRequestAllowed(pindex, consensusParams);        if (!send) {            LogPrint(BCLog::NET, "%s: ignoring request from peer=%i for old block that isn't in the main chain\n", __func__, pfrom.GetId());        }    }    const CNetMsgMaker msgMaker(pfrom.GetCommonVersion());    // disconnect node in case we have reached the outbound limit for serving historical blocks    if (send &&        connman.OutboundTargetReached(true) &&        (((pindexBestHeader != nullptr) && (pindexBestHeader->GetBlockTime() - pindex->GetBlockTime() > HISTORICAL_BLOCK_AGE)) || inv.IsMsgFilteredBlk()) &&        !pfrom.HasPermission(PF_DOWNLOAD) // nodes with the download permission may exceed target    ) {        LogPrint(BCLog::NET, "historical block serving limit reached, disconnect peer=%d\n", pfrom.GetId());        //disconnect node        pfrom.fDisconnect = true;        send = false;    }    // Avoid leaking prune-height by never sending blocks below the NODE_NETWORK_LIMITED threshold    if (send && !pfrom.HasPermission(PF_NOBAN) && (            (((pfrom.GetLocalServices() & NODE_NETWORK_LIMITED) == NODE_NETWORK_LIMITED) && ((pfrom.GetLocalServices() & NODE_NETWORK) != NODE_NETWORK) && (::ChainActive().Tip()->nHeight - pindex->nHeight > (int)NODE_NETWORK_LIMITED_MIN_BLOCKS + 2 /* add two blocks buffer extension for possible races */) )       )) {        LogPrint(BCLog::NET, "Ignore block request below NODE_NETWORK_LIMITED threshold from peer=%d\n", pfrom.GetId());        //disconnect node and prevent it from stalling (would otherwise wait for the missing block)        pfrom.fDisconnect = true;        send = false;    }    // Pruned nodes may have deleted the block, so check whether    // it's available before trying to send.    if (send && (pindex->nStatus & BLOCK_HAVE_DATA))    {        std::shared_ptr<const CBlock> pblock;        if (a_recent_block && a_recent_block->GetHash() == pindex->GetBlockHash()) {            pblock = a_recent_block;        } else if (inv.IsMsgMWEBBlk()) {            // Fast-path: in this case it is possible to serve the block directly from disk,            // as the network format matches the format on disk            std::vector<uint8_t> block_data;            if (!ReadRawBlockFromDisk(block_data, pindex, chainparams.MessageStart())) {                assert(!"cannot load block from disk");            }            connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::BLOCK, MakeSpan(block_data)));            // Don't set pblock as we've sent the block        } else {            // Send block from disk            std::shared_ptr<CBlock> pblockRead = std::make_shared<CBlock>();            if (!ReadBlockFromDisk(*pblockRead, pindex, consensusParams))                assert(!"cannot load block from disk");            pblock = pblockRead;        }        if (pblock) {            if (inv.IsMsgBlk()) {                connman.PushMessage(&pfrom, msgMaker.Make(SERIALIZE_TRANSACTION_NO_WITNESS | SERIALIZE_NO_MWEB, NetMsgType::BLOCK, *pblock));            } else if (inv.IsMsgWitnessBlk()) {                connman.PushMessage(&pfrom, msgMaker.Make(SERIALIZE_NO_MWEB, NetMsgType::BLOCK, *pblock));            } else if (inv.IsMsgMWEBBlk()) {                connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::BLOCK, *pblock));            } else if (inv.IsMsgFilteredBlk()) {                bool sendMerkleBlock = false;                CMerkleBlock merkleBlock;                if (pfrom.m_tx_relay != nullptr) {                    LOCK(pfrom.m_tx_relay->cs_filter);                    if (pfrom.m_tx_relay->pfilter) {                        sendMerkleBlock = true;                        merkleBlock = CMerkleBlock(*pblock, *pfrom.m_tx_relay->pfilter);                    }                }                if (sendMerkleBlock) {                    connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::MERKLEBLOCK, merkleBlock));                    // CMerkleBlock just contains hashes, so also push any transactions in the block the client did not see                    // This avoids hurting performance by pointlessly requiring a round-trip                    // Note that there is currently no way for a node to request any single transactions we didn't send here -                    // they must either disconnect and retry or request the full block.                    // Thus, the protocol spec specified allows for us to provide duplicate txn here,                    // however we MUST always provide at least what the remote peer needs                    typedef std::pair<unsigned int, uint256> PairType;                    for (PairType& pair : merkleBlock.vMatchedTxn)                        connman.PushMessage(&pfrom, msgMaker.Make(SERIALIZE_TRANSACTION_NO_WITNESS | SERIALIZE_NO_MWEB, NetMsgType::TX, *pblock->vtx[pair.first]));                }                // else                    // no response            } else if (inv.IsMsgCmpctBlk()) {                // If a peer is asking for old blocks, we're almost guaranteed                // they won't have a useful mempool to match against a compact block,                // and we don't feel like constructing the object for them, so                // instead we respond with the full, non-compact block.                bool fPeerWantsWitness = State(pfrom.GetId())->fWantsCmpctWitness;                bool fPeerWantsMWEB = State(pfrom.GetId())->fWantsCmpctMWEB;                int nSendFlags = fPeerWantsWitness ? 0 : SERIALIZE_TRANSACTION_NO_WITNESS;                nSendFlags |= fPeerWantsMWEB ? 0 : SERIALIZE_NO_MWEB;                if (CanDirectFetch(consensusParams) && pindex->nHeight >= ::ChainActive().Height() - MAX_CMPCTBLOCK_DEPTH) {                    if ((fPeerWantsWitness || !fWitnessesPresentInARecentCompactBlock) && (fPeerWantsMWEB || !fMWEBPresentInARecentCompactBlock) && a_recent_compact_block && a_recent_compact_block->header.GetHash() == pindex->GetBlockHash()) {                        connman.PushMessage(&pfrom, msgMaker.Make(nSendFlags, NetMsgType::CMPCTBLOCK, *a_recent_compact_block));                    } else {                        CBlockHeaderAndShortTxIDs cmpctblock(*pblock, fPeerWantsWitness);                        connman.PushMessage(&pfrom, msgMaker.Make(nSendFlags, NetMsgType::CMPCTBLOCK, cmpctblock));                    }                } else {                    connman.PushMessage(&pfrom, msgMaker.Make(nSendFlags, NetMsgType::BLOCK, *pblock));                }            } else if (inv.IsMsgMWEBHeader()) {                if (pblock->GetHogEx() != nullptr && !pblock->mweb_block.IsNull()) {                    CMerkleBlockWithMWEB merkle_block_with_mweb(*pblock);                    connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::MWEBHEADER, merkle_block_with_mweb));                }            }        }        // Trigger the peer node to send a getblocks request for the next batch of inventory        if (inv.hash == pfrom.hashContinue)        {            // Send immediately. This must send even if redundant,            // and we want it right after the last block so they don't            // wait for other stuff first.            std::vector<CInv> vInv;            vInv.push_back(CInv(MSG_BLOCK, ::ChainActive().Tip()->GetBlockHash()));            connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::INV, vInv));            pfrom.hashContinue.SetNull();        }    }}struct MWEBLeafsetMsg{    MWEBLeafsetMsg() = default;    MWEBLeafsetMsg(uint256 block_hash_in, BitSet leafset_in)        : block_hash(std::move(block_hash_in)), leafset(std::move(leafset_in)) { }    SERIALIZE_METHODS(MWEBLeafsetMsg, obj) { READWRITE(obj.block_hash, obj.leafset); }    uint256 block_hash;    BitSet leafset;};static void ProcessGetMWEBLeafset(CNode& pfrom, const ChainstateManager& chainman, const CChainParams& chainparams, const CInv& inv, CConnman& connman){    ActivateBestChainIfNeeded(chainparams, inv);    LOCK(cs_main);    if (chainman.ActiveChainstate().IsInitialBlockDownload()) {        LogPrint(BCLog::NET, "Ignoring mweb leafset request from peer=%d because node is in initial block download\n", pfrom.GetId());        return;    }    CBlockIndex* pindex = LookupBlockIndex(inv.hash);    if (!pindex || !chainman.ActiveChain().Contains(pindex)) {        LogPrint(BCLog::NET, "Ignoring mweb leafset request from peer=%d because requested block hash is not in active chain\n", pfrom.GetId());        return;    }    // TODO: Add an outbound limit    // For performance reasons, we limit how many blocks can be undone in order to rebuild the leafset    if (chainman.ActiveChain().Tip()->nHeight - pindex->nHeight > MAX_MWEB_LEAFSET_DEPTH) {        LogPrint(BCLog::NET, "Ignore mweb leafset request below MAX_MWEB_LEAFSET_DEPTH threshold from peer=%d\n", pfrom.GetId());        // disconnect node and prevent it from stalling (would otherwise wait for the MWEB leafset)        if (!pfrom.HasPermission(PF_NOBAN)) {            pfrom.fDisconnect = true;        }        return;    }    // Pruned nodes may have deleted the block, so check whether it's available before trying to send.    if (!(pindex->nStatus & BLOCK_HAVE_DATA) || !(pindex->nStatus & BLOCK_HAVE_MWEB)) {        LogPrint(BCLog::NET, "Ignoring mweb leafset request from peer=%d because block is either pruned or lacking mweb data\n", pfrom.GetId());        if (!pfrom.HasPermission(PF_NOBAN)) {            pfrom.fDisconnect = true;        }        return;    }    // Rewind leafset to block height    BlockValidationState state;    CCoinsViewCache temp_view(&chainman.ActiveChainstate().CoinsTip());    if (!ActivateArbitraryChain(state, temp_view, chainparams, pindex)) {        pfrom.fDisconnect = true;        return;    }    // Serve leafset to peer    MWEBLeafsetMsg leafset_msg(pindex->GetBlockHash(), temp_view.GetMWEBCacheView()->GetLeafSet()->ToBitSet());    connman.PushMessage(&pfrom, CNetMsgMaker(pfrom.GetCommonVersion()).Make(NetMsgType::MWEBLEAFSET, leafset_msg));}struct GetMWEBUTXOsMsg{    GetMWEBUTXOsMsg() = default;    SERIALIZE_METHODS(GetMWEBUTXOsMsg, obj)    {        READWRITE(obj.block_hash, COMPACTSIZE(obj.start_index), obj.num_requested, obj.output_format);    }    uint256 block_hash;    uint64_t start_index;    uint16_t num_requested;    uint8_t output_format;};struct MWEBUTXOsMsg{    MWEBUTXOsMsg() = default;    SERIALIZE_METHODS(MWEBUTXOsMsg, obj)    {        READWRITE(obj.block_hash, COMPACTSIZE(obj.start_index), obj.output_format, obj.utxos, obj.proof_hashes);    }    uint256 block_hash;    uint64_t start_index;    uint8_t output_format;    std::vector<NetUTXO> utxos;    std::vector<mw::Hash> proof_hashes;};static void ProcessGetMWEBUTXOs(CNode& pfrom, const ChainstateManager& chainman, const CChainParams& chainparams, CConnman& connman, const GetMWEBUTXOsMsg& get_utxos){    if (get_utxos.num_requested > MAX_REQUESTED_MWEB_UTXOS) {        LogPrint(BCLog::NET, "getmwebutxos num_requested %u > %u, disconnect peer=%d\n", get_utxos.num_requested, MAX_REQUESTED_MWEB_UTXOS, pfrom.GetId());        if (!pfrom.HasPermission(PF_NOBAN)) {            pfrom.fDisconnect = true;        }        return;    }    static const std::set<uint8_t> supported_formats{        NetUTXO::HASH_ONLY,        NetUTXO::FULL_UTXO,        NetUTXO::COMPACT_UTXO};    if (supported_formats.count(get_utxos.output_format) == 0) {        LogPrint(BCLog::NET, "getmwebutxos output_format %u not supported, disconnect peer=%d\n", get_utxos.output_format, pfrom.GetId());        if (!pfrom.HasPermission(PF_NOBAN)) {            pfrom.fDisconnect = true;        }        return;    }    LOCK(cs_main);    if (chainman.ActiveChainstate().IsInitialBlockDownload()) {        LogPrint(BCLog::NET, "Ignoring getmwebutxos from peer=%d because node is in initial block download\n", pfrom.GetId());        return;    }    CBlockIndex* pindex = LookupBlockIndex(get_utxos.block_hash);    if (!pindex || !chainman.ActiveChain().Contains(pindex)) {        LogPrint(BCLog::NET, "Ignoring getmwebutxos from peer=%d because requested block hash is not in active chain\n", pfrom.GetId());        return;    }    // TODO: Add an outbound limit    // For performance reasons, we limit how many blocks can be undone in order to rebuild the leafset    if (chainman.ActiveChain().Tip()->nHeight - pindex->nHeight > MAX_MWEB_LEAFSET_DEPTH) {        LogPrint(BCLog::NET, "Ignore getmwebutxos below MAX_MWEB_LEAFSET_DEPTH threshold from peer=%d\n", pfrom.GetId());        if (!pfrom.HasPermission(PF_NOBAN)) {            pfrom.fDisconnect = true;        }        return;    }    // Pruned nodes may have deleted the block, so check whether it's available before trying to send.    if (!(pindex->nStatus & BLOCK_HAVE_DATA) || !(pindex->nStatus & BLOCK_HAVE_MWEB)) {        LogPrint(BCLog::NET, "Ignoring getmwebutxos request from peer=%d because block is either pruned or lacking mweb data\n", pfrom.GetId());        if (!pfrom.HasPermission(PF_NOBAN)) {            pfrom.fDisconnect = true;        }        return;    }    // Rewind leafset to block height    BlockValidationState state;    CCoinsViewCache temp_view(&chainman.ActiveChainstate().CoinsTip());    if (!ActivateArbitraryChain(state, temp_view, chainparams, pindex)) {        pfrom.fDisconnect = true;        return;    }    auto mweb_cache = temp_view.GetMWEBCacheView();    mmr::Segment segment = mmr::SegmentFactory::Assemble(        *mweb_cache->GetOutputPMMR(),        *mweb_cache->GetLeafSet(),        mmr::LeafIndex::At(get_utxos.start_index),        get_utxos.num_requested    );    if (segment.leaves.empty()) {        LogPrint(BCLog::NET, "Could not build segment requested by getmwebutxos from peer=%d\n", pfrom.GetId());        pfrom.fDisconnect = true;        return;    }    std::vector<NetUTXO> utxos;    utxos.reserve(segment.leaves.size());    for (const mmr::Leaf& leaf : segment.leaves) {        UTXO::CPtr utxo = mweb_cache->GetUTXO(leaf.vec());        if (!utxo) {            LogPrint(BCLog::NET, "Could not build segment requested by getmwebutxos from peer=%d\n", pfrom.GetId());            pfrom.fDisconnect = true;            return;        }        utxos.push_back(NetUTXO(get_utxos.output_format, utxo));    }    std::vector<mw::Hash> proof_hashes = segment.hashes;    if (segment.lower_peak) {        proof_hashes.push_back(*segment.lower_peak);    }    MWEBUTXOsMsg utxos_msg{        get_utxos.block_hash,        get_utxos.start_index,        get_utxos.output_format,        std::move(utxos),        std::move(proof_hashes)    };    connman.PushMessage(&pfrom, CNetMsgMaker(pfrom.GetCommonVersion()).Make(NetMsgType::MWEBUTXOS, utxos_msg));}//! Determine whether or not a peer can request a transaction, and return it (or nullptr if not found or not allowed).static CTransactionRef FindTxForGetData(const CTxMemPool& mempool, const CNode& peer, const GenTxid& gtxid, const std::chrono::seconds mempool_req, const std::chrono::seconds now) LOCKS_EXCLUDED(cs_main){    auto txinfo = mempool.info(gtxid);    if (txinfo.tx) {        // If a TX could have been INVed in reply to a MEMPOOL request,        // or is older than UNCONDITIONAL_RELAY_DELAY, permit the request        // unconditionally.        if ((mempool_req.count() && txinfo.m_time <= mempool_req) || txinfo.m_time <= now - UNCONDITIONAL_RELAY_DELAY) {            return std::move(txinfo.tx);        }    }    {        LOCK(cs_main);        // Otherwise, the transaction must have been announced recently.        if (State(peer.GetId())->m_recently_announced_invs.contains(gtxid.GetHash())) {            // If it was, it can be relayed from either the mempool...            if (txinfo.tx) return std::move(txinfo.tx);            // ... or the relay pool.            auto mi = mapRelay.find(gtxid.GetHash());            if (mi != mapRelay.end()) return mi->second;        }    }    return {};}void static ProcessGetData(CNode& pfrom, Peer& peer, const ChainstateManager& chainman, const CChainParams& chainparams, CConnman& connman, CTxMemPool& mempool, const std::atomic<bool>& interruptMsgProc) EXCLUSIVE_LOCKS_REQUIRED(!cs_main, peer.m_getdata_requests_mutex){    AssertLockNotHeld(cs_main);    std::deque<CInv>::iterator it = peer.m_getdata_requests.begin();    std::vector<CInv> vNotFound;    const CNetMsgMaker msgMaker(pfrom.GetCommonVersion());    const std::chrono::seconds now = GetTime<std::chrono::seconds>();    // Get last mempool request time    const std::chrono::seconds mempool_req = pfrom.m_tx_relay != nullptr ? pfrom.m_tx_relay->m_last_mempool_req.load()                                                                          : std::chrono::seconds::min();    // Process as many TX items from the front of the getdata queue as    // possible, since they're common and it's efficient to batch process    // them.    while (it != peer.m_getdata_requests.end() && it->IsGenTxMsg()) {        if (interruptMsgProc) return;        // The send buffer provides backpressure. If there's no space in        // the buffer, pause processing until the next call.        if (pfrom.fPauseSend) break;        const CInv &inv = *it++;        if (pfrom.m_tx_relay == nullptr) {            // Ignore GETDATA requests for transactions from blocks-only peers.            continue;        }        CTransactionRef tx = FindTxForGetData(mempool, pfrom, ToGenTxid(inv), mempool_req, now);        if (tx) {            // WTX and WITNESS_TX imply we serialize with witness            int nSendFlags = (inv.IsMsgTx() ? SERIALIZE_TRANSACTION_NO_WITNESS | SERIALIZE_NO_MWEB : (State(pfrom.GetId())->fHaveMWEB ? 0 : SERIALIZE_NO_MWEB));            connman.PushMessage(&pfrom, msgMaker.Make(nSendFlags, NetMsgType::TX, *tx));            mempool.RemoveUnbroadcastTx(tx->GetHash());            // As we're going to send tx, make sure its unconfirmed parents are made requestable.            std::vector<uint256> parent_ids_to_add;            {                LOCK(mempool.cs);                auto txiter = mempool.GetIter(tx->GetHash());                if (txiter) {                    const CTxMemPoolEntry::Parents& parents = (*txiter)->GetMemPoolParentsConst();                    parent_ids_to_add.reserve(parents.size());                    for (const CTxMemPoolEntry& parent : parents) {                        if (parent.GetTime() > now - UNCONDITIONAL_RELAY_DELAY) {                            parent_ids_to_add.push_back(parent.GetTx().GetHash());                        }                    }                }            }            for (const uint256& parent_txid : parent_ids_to_add) {                // Relaying a transaction with a recent but unconfirmed parent.                if (WITH_LOCK(pfrom.m_tx_relay->cs_tx_inventory, return !pfrom.m_tx_relay->filterInventoryKnown.contains(parent_txid))) {                    LOCK(cs_main);                    State(pfrom.GetId())->m_recently_announced_invs.insert(parent_txid);                }            }        } else {            vNotFound.push_back(inv);        }    }    // Only process one BLOCK item per call, since they're uncommon and can be    // expensive to process.    if (it != peer.m_getdata_requests.end() && !pfrom.fPauseSend) {        const CInv &inv = *it++;        if (inv.IsGenBlkMsg()) {            ProcessGetBlockData(pfrom, chainparams, inv, connman);        } else if (inv.IsMsgMWEBLeafset()) {            ProcessGetMWEBLeafset(pfrom, chainman, chainparams, inv, connman);        }        // else: If the first item on the queue is an unknown type, we erase it        // and continue processing the queue on the next call.    }    peer.m_getdata_requests.erase(peer.m_getdata_requests.begin(), it);    if (!vNotFound.empty()) {        // Let the peer know that we didn't find what it asked for, so it doesn't        // have to wait around forever.        // SPV clients care about this message: it's needed when they are        // recursively walking the dependencies of relevant unconfirmed        // transactions. SPV clients want to do that because they want to know        // about (and store and rebroadcast and risk analyze) the dependencies        // of transactions relevant to them, without having to download the        // entire memory pool.        // Also, other nodes can use these messages to automatically request a        // transaction from some other peer that annnounced it, and stop        // waiting for us to respond.        // In normal operation, we often send NOTFOUND messages for parents of        // transactions that we relay; if a peer is missing a parent, they may        // assume we have them and request the parents from us.        connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::NOTFOUND, vNotFound));    }}static uint32_t GetFetchFlags(const CNode& pfrom) EXCLUSIVE_LOCKS_REQUIRED(cs_main) {    uint32_t nFetchFlags = 0;    if ((pfrom.GetLocalServices() & NODE_WITNESS) && State(pfrom.GetId())->fHaveWitness) {        nFetchFlags |= MSG_WITNESS_FLAG;        if ((pfrom.GetLocalServices() & NODE_MWEB) && State(pfrom.GetId())->fHaveMWEB) {            nFetchFlags |= MSG_MWEB_FLAG;        }    }    return nFetchFlags;}void PeerManager::SendBlockTransactions(CNode& pfrom, const CBlock& block, const BlockTransactionsRequest& req) {    BlockTransactions resp(req);    for (size_t i = 0; i < req.indexes.size(); i++) {        if (req.indexes[i] >= block.vtx.size()) {            Misbehaving(pfrom.GetId(), 100, "getblocktxn with out-of-bounds tx indices");            return;        }        resp.txn[i] = block.vtx[req.indexes[i]];    }    LOCK(cs_main);    const CNetMsgMaker msgMaker(pfrom.GetCommonVersion());    int nSendFlags = State(pfrom.GetId())->fWantsCmpctWitness ? 0 : SERIALIZE_TRANSACTION_NO_WITNESS;    nSendFlags |= State(pfrom.GetId())->fWantsCmpctMWEB ? 0 : SERIALIZE_NO_MWEB;    m_connman.PushMessage(&pfrom, msgMaker.Make(nSendFlags, NetMsgType::BLOCKTXN, resp));}void PeerManager::ProcessHeadersMessage(CNode& pfrom, const std::vector<CBlockHeader>& headers, bool via_compact_block){    const CNetMsgMaker msgMaker(pfrom.GetCommonVersion());    size_t nCount = headers.size();    if (nCount == 0) {        // Nothing interesting. Stop asking this peers for more headers.        return;    }    bool received_new_header = false;    const CBlockIndex *pindexLast = nullptr;    {        LOCK(cs_main);        CNodeState *nodestate = State(pfrom.GetId());        // If this looks like it could be a block announcement (nCount <        // MAX_BLOCKS_TO_ANNOUNCE), use special logic for handling headers that        // don't connect:        // - Send a getheaders message in response to try to connect the chain.        // - The peer can send up to MAX_UNCONNECTING_HEADERS in a row that        //   don't connect before giving DoS points        // - Once a headers message is received that is valid and does connect,        //   nUnconnectingHeaders gets reset back to 0.        if (!LookupBlockIndex(headers[0].hashPrevBlock) && nCount < MAX_BLOCKS_TO_ANNOUNCE) {            nodestate->nUnconnectingHeaders++;            m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::GETHEADERS, ::ChainActive().GetLocator(pindexBestHeader), uint256()));            LogPrint(BCLog::NET, "received header %s: missing prev block %s, sending getheaders (%d) to end (peer=%d, nUnconnectingHeaders=%d)\n",                    headers[0].GetHash().ToString(),                    headers[0].hashPrevBlock.ToString(),                    pindexBestHeader->nHeight,                    pfrom.GetId(), nodestate->nUnconnectingHeaders);            // Set hashLastUnknownBlock for this peer, so that if we            // eventually get the headers - even from a different peer -            // we can use this peer to download.            UpdateBlockAvailability(pfrom.GetId(), headers.back().GetHash());            if (nodestate->nUnconnectingHeaders % MAX_UNCONNECTING_HEADERS == 0) {                Misbehaving(pfrom.GetId(), 20, strprintf("%d non-connecting headers", nodestate->nUnconnectingHeaders));            }            return;        }        uint256 hashLastBlock;        for (const CBlockHeader& header : headers) {            if (!hashLastBlock.IsNull() && header.hashPrevBlock != hashLastBlock) {                Misbehaving(pfrom.GetId(), 20, "non-continuous headers sequence");                return;            }            hashLastBlock = header.GetHash();        }        // If we don't have the last header, then they'll have given us        // something new (if these headers are valid).        if (!LookupBlockIndex(hashLastBlock)) {            received_new_header = true;        }    }    BlockValidationState state;    if (!m_chainman.ProcessNewBlockHeaders(headers, state, m_chainparams, &pindexLast)) {        if (state.IsInvalid()) {            MaybePunishNodeForBlock(pfrom.GetId(), state, via_compact_block, "invalid header received");            return;        }    }    {        LOCK(cs_main);        CNodeState *nodestate = State(pfrom.GetId());        if (nodestate->nUnconnectingHeaders > 0) {            LogPrint(BCLog::NET, "peer=%d: resetting nUnconnectingHeaders (%d -> 0)\n", pfrom.GetId(), nodestate->nUnconnectingHeaders);        }        nodestate->nUnconnectingHeaders = 0;        assert(pindexLast);        UpdateBlockAvailability(pfrom.GetId(), pindexLast->GetBlockHash());        // From here, pindexBestKnownBlock should be guaranteed to be non-null,        // because it is set in UpdateBlockAvailability. Some nullptr checks        // are still present, however, as belt-and-suspenders.        if (received_new_header && pindexLast->nChainWork > ::ChainActive().Tip()->nChainWork) {            nodestate->m_last_block_announcement = GetTime();        }        if (nCount == MAX_HEADERS_RESULTS) {            // Headers message had its maximum size; the peer may have more headers.            // TODO: optimize: if pindexLast is an ancestor of ::ChainActive().Tip or pindexBestHeader, continue            // from there instead.            LogPrint(BCLog::NET, "more getheaders (%d) to end to peer=%d (startheight:%d)\n", pindexLast->nHeight, pfrom.GetId(), pfrom.nStartingHeight);            m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::GETHEADERS, ::ChainActive().GetLocator(pindexLast), uint256()));        }        bool fCanDirectFetch = CanDirectFetch(m_chainparams.GetConsensus());        // If this set of headers is valid and ends in a block with at least as        // much work as our tip, download as much as possible.        if (fCanDirectFetch && pindexLast->IsValid(BLOCK_VALID_TREE) && ::ChainActive().Tip()->nChainWork <= pindexLast->nChainWork) {            std::vector<const CBlockIndex*> vToFetch;            const CBlockIndex *pindexWalk = pindexLast;            // Calculate all the blocks we'd need to switch to pindexLast, up to a limit.            while (pindexWalk && !::ChainActive().Contains(pindexWalk) && vToFetch.size() <= MAX_BLOCKS_IN_TRANSIT_PER_PEER) {                if (!(pindexWalk->nStatus & BLOCK_HAVE_DATA) &&                        !mapBlocksInFlight.count(pindexWalk->GetBlockHash()) &&                        (!IsWitnessEnabled(pindexWalk->pprev, m_chainparams.GetConsensus()) || State(pfrom.GetId())->fHaveWitness) &&                        (!IsMWEBEnabled(pindexWalk->pprev, m_chainparams.GetConsensus()) || State(pfrom.GetId())->fHaveMWEB)) {                    // We don't have this block, and it's not yet in flight.                    vToFetch.push_back(pindexWalk);                }                pindexWalk = pindexWalk->pprev;            }            // If pindexWalk still isn't on our main chain, we're looking at a            // very large reorg at a time we think we're close to caught up to            // the main chain -- this shouldn't really happen.  Bail out on the            // direct fetch and rely on parallel download instead.            if (!::ChainActive().Contains(pindexWalk)) {                LogPrint(BCLog::NET, "Large reorg, won't direct fetch to %s (%d)\n",                        pindexLast->GetBlockHash().ToString(),                        pindexLast->nHeight);            } else {                std::vector<CInv> vGetData;                // Download as much as possible, from earliest to latest.                for (const CBlockIndex *pindex : reverse_iterate(vToFetch)) {                    if (nodestate->nBlocksInFlight >= MAX_BLOCKS_IN_TRANSIT_PER_PEER) {                        // Can't download any more from this peer                        break;                    }                    uint32_t nFetchFlags = GetFetchFlags(pfrom);                    vGetData.push_back(CInv(MSG_BLOCK | nFetchFlags, pindex->GetBlockHash()));                    MarkBlockAsInFlight(m_mempool, pfrom.GetId(), pindex->GetBlockHash(), pindex);                    LogPrint(BCLog::NET, "Requesting block %s from  peer=%d\n",                            pindex->GetBlockHash().ToString(), pfrom.GetId());                }                if (vGetData.size() > 1) {                    LogPrint(BCLog::NET, "Downloading blocks toward %s (%d) via headers direct fetch\n",                            pindexLast->GetBlockHash().ToString(), pindexLast->nHeight);                }                if (vGetData.size() > 0) {                    if (nodestate->fSupportsDesiredCmpctVersion && vGetData.size() == 1 && mapBlocksInFlight.size() == 1 && pindexLast->pprev->IsValid(BLOCK_VALID_CHAIN)) {                        // In any case, we want to download using a compact block, not a regular one                        vGetData[0] = CInv(MSG_CMPCT_BLOCK, vGetData[0].hash);                    }                    m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::GETDATA, vGetData));                }            }        }        // If we're in IBD, we want outbound peers that will serve us a useful        // chain. Disconnect peers that are on chains with insufficient work.        if (::ChainstateActive().IsInitialBlockDownload() && nCount != MAX_HEADERS_RESULTS) {            // When nCount < MAX_HEADERS_RESULTS, we know we have no more            // headers to fetch from this peer.            if (nodestate->pindexBestKnownBlock && nodestate->pindexBestKnownBlock->nChainWork < nMinimumChainWork) {                // This peer has too little work on their headers chain to help                // us sync -- disconnect if it is an outbound disconnection                // candidate.                // Note: We compare their tip to nMinimumChainWork (rather than                // ::ChainActive().Tip()) because we won't start block download                // until we have a headers chain that has at least                // nMinimumChainWork, even if a peer has a chain past our tip,                // as an anti-DoS measure.                if (pfrom.IsOutboundOrBlockRelayConn()) {                    LogPrintf("Disconnecting outbound peer %d -- headers chain has insufficient work\n", pfrom.GetId());                    pfrom.fDisconnect = true;                }            }        }        // If this is an outbound full-relay peer, check to see if we should protect        // it from the bad/lagging chain logic.        // Note that outbound block-relay peers are excluded from this protection, and        // thus always subject to eviction under the bad/lagging chain logic.        // See ChainSyncTimeoutState.        if (!pfrom.fDisconnect && pfrom.IsFullOutboundConn() && nodestate->pindexBestKnownBlock != nullptr) {            if (g_outbound_peers_with_protect_from_disconnect < MAX_OUTBOUND_PEERS_TO_PROTECT_FROM_DISCONNECT && nodestate->pindexBestKnownBlock->nChainWork >= ::ChainActive().Tip()->nChainWork && !nodestate->m_chain_sync.m_protect) {                LogPrint(BCLog::NET, "Protecting outbound peer=%d from eviction\n", pfrom.GetId());                nodestate->m_chain_sync.m_protect = true;                ++g_outbound_peers_with_protect_from_disconnect;            }        }    }    return;}/** * Reconsider orphan transactions after a parent has been accepted to the mempool. * * @param[in/out]  orphan_work_set  The set of orphan transactions to reconsider. Generally only one *                                  orphan will be reconsidered on each call of this function. This set *                                  may be added to if accepting an orphan causes its children to be *                                  reconsidered. */void PeerManager::ProcessOrphanTx(std::set<uint256>& orphan_work_set){    AssertLockHeld(cs_main);    AssertLockHeld(g_cs_orphans);    while (!orphan_work_set.empty()) {        const uint256 orphanHash = *orphan_work_set.begin();        orphan_work_set.erase(orphan_work_set.begin());        auto orphan_it = mapOrphanTransactions.find(orphanHash);        if (orphan_it == mapOrphanTransactions.end()) continue;        const CTransactionRef porphanTx = orphan_it->second.tx;        TxValidationState state;        std::list<CTransactionRef> removed_txn;        if (AcceptToMemoryPool(m_mempool, state, porphanTx, &removed_txn, false /* bypass_limits */)) {            LogPrint(BCLog::MEMPOOL, "   accepted orphan tx %s\n", orphanHash.ToString());            RelayTransaction(orphanHash, porphanTx->GetWitnessHash(), m_connman);            for (unsigned int i = 0; i < porphanTx->vout.size(); i++) {                auto it_by_prev = mapOrphanTransactionsByPrev.find(COutPoint(orphanHash, i));                if (it_by_prev != mapOrphanTransactionsByPrev.end()) {                    for (const auto& elem : it_by_prev->second) {                        orphan_work_set.insert(elem->first);                    }                }            }            EraseOrphanTx(orphanHash);            for (const CTransactionRef& removedTx : removed_txn) {                AddToCompactExtraTransactions(removedTx);            }            break;        } else if (state.GetResult() != TxValidationResult::TX_MISSING_INPUTS) {            if (state.IsInvalid()) {                LogPrint(BCLog::MEMPOOL, "   invalid orphan tx %s from peer=%d. %s\n",                    orphanHash.ToString(),                    orphan_it->second.fromPeer,                    state.ToString());                // Maybe punish peer that gave us an invalid orphan tx                MaybePunishNodeForTx(orphan_it->second.fromPeer, state);            }            // Has inputs but not accepted to mempool            // Probably non-standard or insufficient fee            LogPrint(BCLog::MEMPOOL, "   removed orphan tx %s\n", orphanHash.ToString());            if (state.GetResult() != TxValidationResult::TX_WITNESS_STRIPPED) {                // We can add the wtxid of this transaction to our reject filter.                // Do not add txids of witness transactions or witness-stripped                // transactions to the filter, as they can have been malleated;                // adding such txids to the reject filter would potentially                // interfere with relay of valid transactions from peers that                // do not support wtxid-based relay. See                // https://github.com/bitcoin/bitcoin/issues/8279 for details.                // We can remove this restriction (and always add wtxids to                // the filter even for witness stripped transactions) once                // wtxid-based relay is broadly deployed.                // See also comments in https://github.com/bitcoin/bitcoin/pull/18044#discussion_r443419034                // for concerns around weakening security of unupgraded nodes                // if we start doing this too early.                assert(recentRejects);                recentRejects->insert(porphanTx->GetWitnessHash());                // If the transaction failed for TX_INPUTS_NOT_STANDARD,                // then we know that the witness was irrelevant to the policy                // failure, since this check depends only on the txid                // (the scriptPubKey being spent is covered by the txid).                // Add the txid to the reject filter to prevent repeated                // processing of this transaction in the event that child                // transactions are later received (resulting in                // parent-fetching by txid via the orphan-handling logic).                if (state.GetResult() == TxValidationResult::TX_INPUTS_NOT_STANDARD && porphanTx->GetWitnessHash() != porphanTx->GetHash()) {                    // We only add the txid if it differs from the wtxid, to                    // avoid wasting entries in the rolling bloom filter.                    recentRejects->insert(porphanTx->GetHash());                }            }            EraseOrphanTx(orphanHash);            break;        }    }    m_mempool.check(&::ChainstateActive().CoinsTip());}/** * Validation logic for compact filters request handling. * * May disconnect from the peer in the case of a bad request. * * @param[in]   peer            The peer that we received the request from * @param[in]   chain_params    Chain parameters * @param[in]   filter_type     The filter type the request is for. Must be basic filters. * @param[in]   start_height    The start height for the request * @param[in]   stop_hash       The stop_hash for the request * @param[in]   max_height_diff The maximum number of items permitted to request, as specified in BIP 157 * @param[out]  stop_index      The CBlockIndex for the stop_hash block, if the request can be serviced. * @param[out]  filter_index    The filter index, if the request can be serviced. * @return                      True if the request can be serviced. */static bool PrepareBlockFilterRequest(CNode& peer, const CChainParams& chain_params,                                      BlockFilterType filter_type, uint32_t start_height,                                      const uint256& stop_hash, uint32_t max_height_diff,                                      const CBlockIndex*& stop_index,                                      BlockFilterIndex*& filter_index){    const bool supported_filter_type =        (filter_type == BlockFilterType::BASIC &&         (peer.GetLocalServices() & NODE_COMPACT_FILTERS));    if (!supported_filter_type) {        LogPrint(BCLog::NET, "peer %d requested unsupported block filter type: %d\n",                 peer.GetId(), static_cast<uint8_t>(filter_type));        peer.fDisconnect = true;        return false;    }    {        LOCK(cs_main);        stop_index = LookupBlockIndex(stop_hash);        // Check that the stop block exists and the peer would be allowed to fetch it.        if (!stop_index || !BlockRequestAllowed(stop_index, chain_params.GetConsensus())) {            LogPrint(BCLog::NET, "peer %d requested invalid block hash: %s\n",                     peer.GetId(), stop_hash.ToString());            peer.fDisconnect = true;            return false;        }    }    uint32_t stop_height = stop_index->nHeight;    if (start_height > stop_height) {        LogPrint(BCLog::NET, "peer %d sent invalid getcfilters/getcfheaders with " /* Continued */                 "start height %d and stop height %d\n",                 peer.GetId(), start_height, stop_height);        peer.fDisconnect = true;        return false;    }    if (stop_height - start_height >= max_height_diff) {        LogPrint(BCLog::NET, "peer %d requested too many cfilters/cfheaders: %d / %d\n",                 peer.GetId(), stop_height - start_height + 1, max_height_diff);        peer.fDisconnect = true;        return false;    }    filter_index = GetBlockFilterIndex(filter_type);    if (!filter_index) {        LogPrint(BCLog::NET, "Filter index for supported type %s not found\n", BlockFilterTypeName(filter_type));        return false;    }    return true;}/** * Handle a cfilters request. * * May disconnect from the peer in the case of a bad request. * * @param[in]   peer            The peer that we received the request from * @param[in]   vRecv           The raw message received * @param[in]   chain_params    Chain parameters * @param[in]   connman         Pointer to the connection manager */static void ProcessGetCFilters(CNode& peer, CDataStream& vRecv, const CChainParams& chain_params,                               CConnman& connman){    uint8_t filter_type_ser;    uint32_t start_height;    uint256 stop_hash;    vRecv >> filter_type_ser >> start_height >> stop_hash;    const BlockFilterType filter_type = static_cast<BlockFilterType>(filter_type_ser);    const CBlockIndex* stop_index;    BlockFilterIndex* filter_index;    if (!PrepareBlockFilterRequest(peer, chain_params, filter_type, start_height, stop_hash,                                   MAX_GETCFILTERS_SIZE, stop_index, filter_index)) {        return;    }    std::vector<BlockFilter> filters;    if (!filter_index->LookupFilterRange(start_height, stop_index, filters)) {        LogPrint(BCLog::NET, "Failed to find block filter in index: filter_type=%s, start_height=%d, stop_hash=%s\n",                     BlockFilterTypeName(filter_type), start_height, stop_hash.ToString());        return;    }    for (const auto& filter : filters) {        CSerializedNetMsg msg = CNetMsgMaker(peer.GetCommonVersion())            .Make(NetMsgType::CFILTER, filter);        connman.PushMessage(&peer, std::move(msg));    }}/** * Handle a cfheaders request. * * May disconnect from the peer in the case of a bad request. * * @param[in]   peer            The peer that we received the request from * @param[in]   vRecv           The raw message received * @param[in]   chain_params    Chain parameters * @param[in]   connman         Pointer to the connection manager */static void ProcessGetCFHeaders(CNode& peer, CDataStream& vRecv, const CChainParams& chain_params,                                CConnman& connman){    uint8_t filter_type_ser;    uint32_t start_height;    uint256 stop_hash;    vRecv >> filter_type_ser >> start_height >> stop_hash;    const BlockFilterType filter_type = static_cast<BlockFilterType>(filter_type_ser);    const CBlockIndex* stop_index;    BlockFilterIndex* filter_index;    if (!PrepareBlockFilterRequest(peer, chain_params, filter_type, start_height, stop_hash,                                   MAX_GETCFHEADERS_SIZE, stop_index, filter_index)) {        return;    }    uint256 prev_header;    if (start_height > 0) {        const CBlockIndex* const prev_block =            stop_index->GetAncestor(static_cast<int>(start_height - 1));        if (!filter_index->LookupFilterHeader(prev_block, prev_header)) {            LogPrint(BCLog::NET, "Failed to find block filter header in index: filter_type=%s, block_hash=%s\n",                         BlockFilterTypeName(filter_type), prev_block->GetBlockHash().ToString());            return;        }    }    std::vector<uint256> filter_hashes;    if (!filter_index->LookupFilterHashRange(start_height, stop_index, filter_hashes)) {        LogPrint(BCLog::NET, "Failed to find block filter hashes in index: filter_type=%s, start_height=%d, stop_hash=%s\n",                     BlockFilterTypeName(filter_type), start_height, stop_hash.ToString());        return;    }    CSerializedNetMsg msg = CNetMsgMaker(peer.GetCommonVersion())        .Make(NetMsgType::CFHEADERS,              filter_type_ser,              stop_index->GetBlockHash(),              prev_header,              filter_hashes);    connman.PushMessage(&peer, std::move(msg));}/** * Handle a getcfcheckpt request. * * May disconnect from the peer in the case of a bad request. * * @param[in]   peer            The peer that we received the request from * @param[in]   vRecv           The raw message received * @param[in]   chain_params    Chain parameters * @param[in]   connman         Pointer to the connection manager */static void ProcessGetCFCheckPt(CNode& peer, CDataStream& vRecv, const CChainParams& chain_params,                                CConnman& connman){    uint8_t filter_type_ser;    uint256 stop_hash;    vRecv >> filter_type_ser >> stop_hash;    const BlockFilterType filter_type = static_cast<BlockFilterType>(filter_type_ser);    const CBlockIndex* stop_index;    BlockFilterIndex* filter_index;    if (!PrepareBlockFilterRequest(peer, chain_params, filter_type, /*start_height=*/0, stop_hash,                                   /*max_height_diff=*/std::numeric_limits<uint32_t>::max(),                                   stop_index, filter_index)) {        return;    }    std::vector<uint256> headers(stop_index->nHeight / CFCHECKPT_INTERVAL);    // Populate headers.    const CBlockIndex* block_index = stop_index;    for (int i = headers.size() - 1; i >= 0; i--) {        int height = (i + 1) * CFCHECKPT_INTERVAL;        block_index = block_index->GetAncestor(height);        if (!filter_index->LookupFilterHeader(block_index, headers[i])) {            LogPrint(BCLog::NET, "Failed to find block filter header in index: filter_type=%s, block_hash=%s\n",                         BlockFilterTypeName(filter_type), block_index->GetBlockHash().ToString());            return;        }    }    CSerializedNetMsg msg = CNetMsgMaker(peer.GetCommonVersion())        .Make(NetMsgType::CFCHECKPT,              filter_type_ser,              stop_index->GetBlockHash(),              headers);    connman.PushMessage(&peer, std::move(msg));}void PeerManager::ProcessMessage(CNode& pfrom, const std::string& msg_type, CDataStream& vRecv,                                         const std::chrono::microseconds time_received,                                         const std::atomic<bool>& interruptMsgProc){    LogPrint(BCLog::NET, "received: %s (%u bytes) peer=%d\n", SanitizeString(msg_type), vRecv.size(), pfrom.GetId());    if (gArgs.IsArgSet("-dropmessagestest") && GetRand(gArgs.GetArg("-dropmessagestest", 0)) == 0)    {        LogPrintf("dropmessagestest DROPPING RECV MESSAGE\n");        return;    }    PeerRef peer = GetPeerRef(pfrom.GetId());    if (peer == nullptr) return;    if (msg_type == NetMsgType::VERSION) {        // Each connection can only send one version message        if (pfrom.nVersion != 0)        {            Misbehaving(pfrom.GetId(), 1, "redundant version message");            return;        }        int64_t nTime;        CAddress addrMe;        CAddress addrFrom;        uint64_t nNonce = 1;        uint64_t nServiceInt;        ServiceFlags nServices;        int nVersion;        std::string cleanSubVer;        int nStartingHeight = -1;        bool fRelay = true;        vRecv >> nVersion >> nServiceInt >> nTime >> addrMe;        if (nTime < 0) {            nTime = 0;        }        nServices = ServiceFlags(nServiceInt);        if (!pfrom.IsInboundConn())        {            m_connman.SetServices(pfrom.addr, nServices);        }        if (pfrom.ExpectServicesFromConn() && !HasAllDesirableServiceFlags(nServices))        {            LogPrint(BCLog::NET, "peer=%d does not offer the expected services (%08x offered, %08x expected); disconnecting\n", pfrom.GetId(), nServices, GetDesirableServiceFlags(nServices));            pfrom.fDisconnect = true;            return;        }        if (nVersion < MIN_PEER_PROTO_VERSION) {            // disconnect from peers older than this proto version            LogPrint(BCLog::NET, "peer=%d using obsolete version %i; disconnecting\n", pfrom.GetId(), nVersion);            pfrom.fDisconnect = true;            return;        }        if (!vRecv.empty())            vRecv >> addrFrom >> nNonce;        if (!vRecv.empty()) {            std::string strSubVer;            vRecv >> LIMITED_STRING(strSubVer, MAX_SUBVERSION_LENGTH);            cleanSubVer = SanitizeString(strSubVer);        }        if (!vRecv.empty()) {            vRecv >> nStartingHeight;        }        if (!vRecv.empty())            vRecv >> fRelay;        // Disconnect if we connected to ourself        if (pfrom.IsInboundConn() && !m_connman.CheckIncomingNonce(nNonce))        {            LogPrintf("connected to self at %s, disconnecting\n", pfrom.addr.ToString());            pfrom.fDisconnect = true;            return;        }        if (pfrom.IsInboundConn() && addrMe.IsRoutable())        {            SeenLocal(addrMe);        }        // Be shy and don't send version until we hear        if (pfrom.IsInboundConn())            PushNodeVersion(pfrom, m_connman, GetAdjustedTime());        // Change version        const int greatest_common_version = std::min(nVersion, PROTOCOL_VERSION);        pfrom.SetCommonVersion(greatest_common_version);        pfrom.nVersion = nVersion;        const CNetMsgMaker msg_maker(greatest_common_version);        if (greatest_common_version >= WTXID_RELAY_VERSION) {            m_connman.PushMessage(&pfrom, msg_maker.Make(NetMsgType::WTXIDRELAY));        }        // Signal ADDRv2 support (BIP155).        if (greatest_common_version >= 70016) {            // BIP155 defines addrv2 and sendaddrv2 for all protocol versions, but some            // implementations reject messages they don't know. As a courtesy, don't send            // it to nodes with a version before 70016, as no software is known to support            // BIP155 that doesn't announce at least that protocol version number.            m_connman.PushMessage(&pfrom, msg_maker.Make(NetMsgType::SENDADDRV2));        }        m_connman.PushMessage(&pfrom, msg_maker.Make(NetMsgType::VERACK));        pfrom.nServices = nServices;        pfrom.SetAddrLocal(addrMe);        {            LOCK(pfrom.cs_SubVer);            pfrom.cleanSubVer = cleanSubVer;        }        pfrom.nStartingHeight = nStartingHeight;        // set nodes not relaying blocks and tx and not serving (parts) of the historical blockchain as "clients"        pfrom.fClient = (!(nServices & NODE_NETWORK) && !(nServices & NODE_NETWORK_LIMITED));        // set nodes not capable of serving the complete blockchain history as "limited nodes"        pfrom.m_limited_node = (!(nServices & NODE_NETWORK) && (nServices & NODE_NETWORK_LIMITED));        if (pfrom.m_tx_relay != nullptr) {            LOCK(pfrom.m_tx_relay->cs_filter);            pfrom.m_tx_relay->fRelayTxes = fRelay; // set to true after we get the first filter* message        }        if((nServices & NODE_WITNESS))        {            LOCK(cs_main);            State(pfrom.GetId())->fHaveWitness = true;            if (nServices & NODE_MWEB) {                State(pfrom.GetId())->fHaveMWEB = true;            }        }        // Potentially mark this peer as a preferred download peer.        {        LOCK(cs_main);        UpdatePreferredDownload(pfrom, State(pfrom.GetId()));        }        if (!pfrom.IsInboundConn() && !pfrom.IsBlockOnlyConn()) {            // For outbound peers, we try to relay our address (so that other            // nodes can try to find us more quickly, as we have no guarantee            // that an outbound peer is even aware of how to reach us) and do a            // one-time address fetch (to help populate/update our addrman). If            // we're starting up for the first time, our addrman may be pretty            // empty and no one will know who we are, so these mechanisms are            // important to help us connect to the network.            //            // We skip this for BLOCK_RELAY peers to avoid potentially leaking            // information about our BLOCK_RELAY connections via address relay.            if (fListen && !::ChainstateActive().IsInitialBlockDownload())            {                CAddress addr = GetLocalAddress(&pfrom.addr, pfrom.GetLocalServices());                FastRandomContext insecure_rand;                if (addr.IsRoutable())                {                    LogPrint(BCLog::NET, "ProcessMessages: advertising address %s\n", addr.ToString());                    pfrom.PushAddress(addr, insecure_rand);                } else if (IsPeerAddrLocalGood(&pfrom)) {                    addr.SetIP(addrMe);                    LogPrint(BCLog::NET, "ProcessMessages: advertising address %s\n", addr.ToString());                    pfrom.PushAddress(addr, insecure_rand);                }            }            // Get recent addresses            m_connman.PushMessage(&pfrom, CNetMsgMaker(greatest_common_version).Make(NetMsgType::GETADDR));            pfrom.fGetAddr = true;            // When requesting a getaddr, accept an additional MAX_ADDR_TO_SEND addresses in response            // (bypassing the MAX_ADDR_PROCESSING_TOKEN_BUCKET limit).            peer->m_addr_token_bucket += MAX_ADDR_TO_SEND;        }        if (!pfrom.IsInboundConn()) {            // For non-inbound connections, we update the addrman to record            // connection success so that addrman will have an up-to-date            // notion of which peers are online and available.            //            // While we strive to not leak information about block-relay-only            // connections via the addrman, not moving an address to the tried            // table is also potentially detrimental because new-table entries            // are subject to eviction in the event of addrman collisions.  We            // mitigate the information-leak by never calling            // CAddrMan::Connected() on block-relay-only peers; see            // FinalizeNode().            //            // This moves an address from New to Tried table in Addrman,            // resolves tried-table collisions, etc.            m_connman.MarkAddressGood(pfrom.addr);        }        std::string remoteAddr;        if (fLogIPs)            remoteAddr = ", peeraddr=" + pfrom.addr.ToString();        LogPrint(BCLog::NET, "receive version message: %s: version %d, blocks=%d, us=%s, peer=%d%s\n",                  cleanSubVer, pfrom.nVersion,                  pfrom.nStartingHeight, addrMe.ToString(), pfrom.GetId(),                  remoteAddr);        int64_t nTimeOffset = nTime - GetTime();        pfrom.nTimeOffset = nTimeOffset;        AddTimeData(pfrom.addr, nTimeOffset);        // If the peer is old enough to have the old alert system, send it the final alert.        if (greatest_common_version <= 70012) {            CDataStream finalAlert(ParseHex("5c0100000015f7675900000000ffffff7f00000000ffffff7ffeffff7f0000000000ffffff7f00ffffff7f002f555247454e543a20416c657274206b657920636f6d70726f6d697365642c2075706772616465207265717569726564004630440220405f7e7572b176f3316d4e12deab75ad4ff978844f7a7bcd5ed06f6aa094eb6602207880fcc07d0a78e0f46f188d115e04ed4ad48980ea3572cb0e0cb97921048095"), SER_NETWORK, PROTOCOL_VERSION);            m_connman.PushMessage(&pfrom, CNetMsgMaker(greatest_common_version).Make("alert", finalAlert));        }        // Feeler connections exist only to verify if address is online.        if (pfrom.IsFeelerConn()) {            pfrom.fDisconnect = true;        }        return;    }    if (pfrom.nVersion == 0) {        // Must have a version message before anything else        Misbehaving(pfrom.GetId(), 1, "non-version message before version handshake");        return;    }    // At this point, the outgoing message serialization version can't change.    const CNetMsgMaker msgMaker(pfrom.GetCommonVersion());    if (msg_type == NetMsgType::VERACK) {        if (pfrom.fSuccessfullyConnected) return;        if (!pfrom.IsInboundConn()) {            // Mark this node as currently connected, so we update its timestamp later.            LOCK(cs_main);            State(pfrom.GetId())->fCurrentlyConnected = true;            LogPrintf("New outbound peer connected: version: %d, blocks=%d, peer=%d%s (%s)\n",                      pfrom.nVersion.load(), pfrom.nStartingHeight,                      pfrom.GetId(), (fLogIPs ? strprintf(", peeraddr=%s", pfrom.addr.ToString()) : ""),                      pfrom.m_tx_relay == nullptr ? "block-relay" : "full-relay");        }        if (pfrom.GetCommonVersion() >= SENDHEADERS_VERSION) {            // Tell our peer we prefer to receive headers rather than inv's            // We send this to non-NODE NETWORK peers as well, because even            // non-NODE NETWORK peers can announce blocks (such as pruning            // nodes)            m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::SENDHEADERS));        }        if (pfrom.GetCommonVersion() >= SHORT_IDS_BLOCKS_VERSION) {            // Tell our peer we are willing to provide version 1 or 2 cmpctblocks            // However, we do not request new block announcements using            // cmpctblock messages.            // We send this to non-NODE NETWORK peers as well, because            // they may wish to request compact blocks from us            bool fAnnounceUsingCMPCTBLOCK = false;            uint64_t nCMPCTBLOCKVersion = 3;            if (pfrom.GetLocalServices() & NODE_MWEB)                m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::SENDCMPCT, fAnnounceUsingCMPCTBLOCK, nCMPCTBLOCKVersion));            nCMPCTBLOCKVersion = 2;            if (pfrom.GetLocalServices() & NODE_WITNESS)                m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::SENDCMPCT, fAnnounceUsingCMPCTBLOCK, nCMPCTBLOCKVersion));            nCMPCTBLOCKVersion = 1;            m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::SENDCMPCT, fAnnounceUsingCMPCTBLOCK, nCMPCTBLOCKVersion));        }        pfrom.fSuccessfullyConnected = true;        return;    }    // Feature negotiation of wtxidrelay should happen between VERSION and    // VERACK, to avoid relay problems from switching after a connection is up    if (msg_type == NetMsgType::WTXIDRELAY) {        if (pfrom.fSuccessfullyConnected) {            // Disconnect peers that send wtxidrelay message after VERACK; this            // must be negotiated between VERSION and VERACK.            pfrom.fDisconnect = true;            return;        }        if (pfrom.GetCommonVersion() >= WTXID_RELAY_VERSION) {            LOCK(cs_main);            if (!State(pfrom.GetId())->m_wtxid_relay) {                State(pfrom.GetId())->m_wtxid_relay = true;                g_wtxid_relay_peers++;            }        }        return;    }    if (msg_type == NetMsgType::SENDADDRV2) {        if (pfrom.fSuccessfullyConnected) {            // Disconnect peers that send SENDADDRV2 message after VERACK; this            // must be negotiated between VERSION and VERACK.            pfrom.fDisconnect = true;            return;        }        pfrom.m_wants_addrv2 = true;        return;    }    if (!pfrom.fSuccessfullyConnected) {        LogPrint(BCLog::NET, "Unsupported message \"%s\" prior to verack from peer=%d\n", SanitizeString(msg_type), pfrom.GetId());        return;    }    if (msg_type == NetMsgType::ADDR || msg_type == NetMsgType::ADDRV2) {        int stream_version = vRecv.GetVersion();        if (msg_type == NetMsgType::ADDRV2) {            // Add ADDRV2_FORMAT to the version so that the CNetAddr and CAddress            // unserialize methods know that an address in v2 format is coming.            stream_version |= ADDRV2_FORMAT;        }        OverrideStream<CDataStream> s(&vRecv, vRecv.GetType(), stream_version);        std::vector<CAddress> vAddr;        s >> vAddr;        if (!pfrom.RelayAddrsWithConn()) {            return;        }        if (vAddr.size() > MAX_ADDR_TO_SEND)        {            Misbehaving(pfrom.GetId(), 20, strprintf("%s message size = %u", msg_type, vAddr.size()));            return;        }        // Store the new addresses        std::vector<CAddress> vAddrOk;        int64_t nNow = GetAdjustedTime();        int64_t nSince = nNow - 10 * 60;        // Update/increment addr rate limiting bucket.        const auto current_time{GetTime<std::chrono::microseconds>()};        if (peer->m_addr_token_bucket < MAX_ADDR_PROCESSING_TOKEN_BUCKET) {            // Don't increment bucket if it's already full            const auto time_diff = std::max(current_time - peer->m_addr_token_timestamp, 0us);            const double increment = Ticks<SecondsDouble>(time_diff) * MAX_ADDR_RATE_PER_SECOND;            peer->m_addr_token_bucket = std::min<double>(peer->m_addr_token_bucket + increment, MAX_ADDR_PROCESSING_TOKEN_BUCKET);        }        peer->m_addr_token_timestamp = current_time;        const bool rate_limited = !pfrom.HasPermission(NetPermissionFlags::PF_ADDR);        uint64_t num_proc = 0;        uint64_t num_rate_limit = 0;        Shuffle(vAddr.begin(), vAddr.end(), FastRandomContext());        for (CAddress& addr : vAddr)        {            if (interruptMsgProc)                return;            // Apply rate limiting.            if (peer->m_addr_token_bucket < 1.0) {                if (rate_limited) {                    ++num_rate_limit;                    continue;                }            } else {                peer->m_addr_token_bucket -= 1.0;            }            // We only bother storing full nodes, though this may include            // things which we would not make an outbound connection to, in            // part because we may make feeler connections to them.            if (!MayHaveUsefulAddressDB(addr.nServices) && !HasAllDesirableServiceFlags(addr.nServices))                continue;            if (addr.nTime <= 100000000 || addr.nTime > nNow + 10 * 60)                addr.nTime = nNow - 5 * 24 * 60 * 60;            pfrom.AddAddressKnown(addr);            if (m_banman && (m_banman->IsDiscouraged(addr) || m_banman->IsBanned(addr))) {                // Do not process banned/discouraged addresses beyond remembering we received them                continue;            }            ++num_proc;            bool fReachable = IsReachable(addr);            if (addr.nTime > nSince && !pfrom.fGetAddr && vAddr.size() <= 10 && addr.IsRoutable())            {                // Relay to a limited number of other nodes                RelayAddress(addr, fReachable, m_connman);            }            // Do not store addresses outside our network            if (fReachable)                vAddrOk.push_back(addr);        }        peer->m_addr_processed += num_proc;        peer->m_addr_rate_limited += num_rate_limit;        LogPrint(BCLog::NET, "Received addr: %u addresses (%u processed, %u rate-limited) from peer=%d\n",                 vAddr.size(), num_proc, num_rate_limit, pfrom.GetId());        m_connman.AddNewAddresses(vAddrOk, pfrom.addr, 2 * 60 * 60);        if (vAddr.size() < 1000)            pfrom.fGetAddr = false;        if (pfrom.IsAddrFetchConn())            pfrom.fDisconnect = true;        return;    }    if (msg_type == NetMsgType::SENDHEADERS) {        LOCK(cs_main);        State(pfrom.GetId())->fPreferHeaders = true;        return;    }    if (msg_type == NetMsgType::SENDCMPCT) {        bool fAnnounceUsingCMPCTBLOCK = false;        uint64_t nCMPCTBLOCKVersion = 0;        vRecv >> fAnnounceUsingCMPCTBLOCK >> nCMPCTBLOCKVersion;        if (nCMPCTBLOCKVersion == 1 || ((pfrom.GetLocalServices() & NODE_WITNESS) && nCMPCTBLOCKVersion == 2) || ((pfrom.GetLocalServices() & NODE_MWEB) && nCMPCTBLOCKVersion == 3)) {            LOCK(cs_main);            // fProvidesHeaderAndIDs is used to "lock in" version of compact blocks we send (fWantsCmpctWitness)            if (!State(pfrom.GetId())->fProvidesHeaderAndIDs) {                State(pfrom.GetId())->fProvidesHeaderAndIDs = true;                State(pfrom.GetId())->fWantsCmpctWitness = nCMPCTBLOCKVersion >= 2;                State(pfrom.GetId())->fWantsCmpctMWEB = nCMPCTBLOCKVersion >= 3;            }            if (State(pfrom.GetId())->fWantsCmpctWitness == (nCMPCTBLOCKVersion >= 2) && State(pfrom.GetId())->fWantsCmpctMWEB == (nCMPCTBLOCKVersion >= 3))                State(pfrom.GetId())->fPreferHeaderAndIDs = fAnnounceUsingCMPCTBLOCK;            if (!State(pfrom.GetId())->fSupportsDesiredCmpctVersion) {                if (pfrom.GetLocalServices() & NODE_MWEB)                    State(pfrom.GetId())->fSupportsDesiredCmpctVersion = (nCMPCTBLOCKVersion == 3);                 else if (pfrom.GetLocalServices() & NODE_WITNESS)                    State(pfrom.GetId())->fSupportsDesiredCmpctVersion = (nCMPCTBLOCKVersion == 2);                else                    State(pfrom.GetId())->fSupportsDesiredCmpctVersion = (nCMPCTBLOCKVersion == 1);            }        }        return;    }    if (msg_type == NetMsgType::INV) {        std::vector<CInv> vInv;        vRecv >> vInv;        if (vInv.size() > MAX_INV_SZ)        {            Misbehaving(pfrom.GetId(), 20, strprintf("inv message size = %u", vInv.size()));            return;        }        // We won't accept tx inv's if we're in blocks-only mode, or this is a        // block-relay-only peer        bool fBlocksOnly = !g_relay_txes || (pfrom.m_tx_relay == nullptr);        // Allow peers with relay permission to send data other than blocks in blocks only mode        if (pfrom.HasPermission(PF_RELAY)) {            fBlocksOnly = false;        }        LOCK(cs_main);        const auto current_time = GetTime<std::chrono::microseconds>();        uint256* best_block{nullptr};        for (CInv& inv : vInv) {            if (interruptMsgProc) return;            // Ignore INVs that don't match wtxidrelay setting.            // Note that orphan parent fetching always uses MSG_TX GETDATAs regardless of the wtxidrelay setting.            // This is fine as no INV messages are involved in that process.            if (State(pfrom.GetId())->m_wtxid_relay) {                if (inv.IsMsgTx()) continue;            } else {                if (inv.IsMsgWtx()) continue;            }            if (inv.IsMsgBlk()) {                const bool fAlreadyHave = AlreadyHaveBlock(inv.hash);                LogPrint(BCLog::NET, "got inv: %s  %s peer=%d\n", inv.ToString(), fAlreadyHave ? "have" : "new", pfrom.GetId());                UpdateBlockAvailability(pfrom.GetId(), inv.hash);                if (!fAlreadyHave && !fImporting && !fReindex && !mapBlocksInFlight.count(inv.hash)) {                    // Headers-first is the primary method of announcement on                    // the network. If a node fell back to sending blocks by inv,                    // it's probably for a re-org. The final block hash                    // provided should be the highest, so send a getheaders and                    // then fetch the blocks we need to catch up.                    best_block = &inv.hash;                }            } else if (inv.IsGenTxMsg()) {                const GenTxid gtxid = ToGenTxid(inv);                const bool fAlreadyHave = AlreadyHaveTx(gtxid, m_mempool);                LogPrint(BCLog::NET, "got inv: %s  %s peer=%d\n", inv.ToString(), fAlreadyHave ? "have" : "new", pfrom.GetId());                pfrom.AddKnownTx(inv.hash);                if (fBlocksOnly) {                    LogPrint(BCLog::NET, "transaction (%s) inv sent in violation of protocol, disconnecting peer=%d\n", inv.hash.ToString(), pfrom.GetId());                    pfrom.fDisconnect = true;                    return;                } else if (!fAlreadyHave && !m_chainman.ActiveChainstate().IsInitialBlockDownload()) {                    AddTxAnnouncement(pfrom, gtxid, current_time);                }            } else {                LogPrint(BCLog::NET, "Unknown inv type \"%s\" received from peer=%d\n", inv.ToString(), pfrom.GetId());            }        }        if (best_block != nullptr) {            m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::GETHEADERS, ::ChainActive().GetLocator(pindexBestHeader), *best_block));            LogPrint(BCLog::NET, "getheaders (%d) %s to peer=%d\n", pindexBestHeader->nHeight, best_block->ToString(), pfrom.GetId());        }        return;    }    if (msg_type == NetMsgType::GETDATA) {        std::vector<CInv> vInv;        vRecv >> vInv;        if (vInv.size() > MAX_INV_SZ)        {            Misbehaving(pfrom.GetId(), 20, strprintf("getdata message size = %u", vInv.size()));            return;        }        LogPrint(BCLog::NET, "received getdata (%u invsz) peer=%d\n", vInv.size(), pfrom.GetId());        if (vInv.size() > 0) {            LogPrint(BCLog::NET, "received getdata for: %s peer=%d\n", vInv[0].ToString(), pfrom.GetId());        }        {            LOCK(peer->m_getdata_requests_mutex);            peer->m_getdata_requests.insert(peer->m_getdata_requests.end(), vInv.begin(), vInv.end());            ProcessGetData(pfrom, *peer, m_chainman, m_chainparams, m_connman, m_mempool, interruptMsgProc);        }        return;    }    if (msg_type == NetMsgType::GETBLOCKS) {        CBlockLocator locator;        uint256 hashStop;        vRecv >> locator >> hashStop;        if (locator.vHave.size() > MAX_LOCATOR_SZ) {            LogPrint(BCLog::NET, "getblocks locator size %lld > %d, disconnect peer=%d\n", locator.vHave.size(), MAX_LOCATOR_SZ, pfrom.GetId());            pfrom.fDisconnect = true;            return;        }        // We might have announced the currently-being-connected tip using a        // compact block, which resulted in the peer sending a getblocks        // request, which we would otherwise respond to without the new block.        // To avoid this situation we simply verify that we are on our best        // known chain now. This is super overkill, but we handle it better        // for getheaders requests, and there are no known nodes which support        // compact blocks but still use getblocks to request blocks.        {            std::shared_ptr<const CBlock> a_recent_block;            {                LOCK(cs_most_recent_block);                a_recent_block = most_recent_block;            }            BlockValidationState state;            if (!ActivateBestChain(state, m_chainparams, a_recent_block)) {                LogPrint(BCLog::NET, "failed to activate chain (%s)\n", state.ToString());            }        }        LOCK(cs_main);        // Find the last block the caller has in the main chain        const CBlockIndex* pindex = FindForkInGlobalIndex(::ChainActive(), locator);        // Send the rest of the chain        if (pindex)            pindex = ::ChainActive().Next(pindex);        int nLimit = 500;        LogPrint(BCLog::NET, "getblocks %d to %s limit %d from peer=%d\n", (pindex ? pindex->nHeight : -1), hashStop.IsNull() ? "end" : hashStop.ToString(), nLimit, pfrom.GetId());        for (; pindex; pindex = ::ChainActive().Next(pindex))        {            if (pindex->GetBlockHash() == hashStop)            {                LogPrint(BCLog::NET, "  getblocks stopping at %d %s\n", pindex->nHeight, pindex->GetBlockHash().ToString());                break;            }            // If pruning, don't inv blocks unless we have on disk and are likely to still have            // for some reasonable time window (1 hour) that block relay might require.            const int nPrunedBlocksLikelyToHave = MIN_BLOCKS_TO_KEEP - 3600 / m_chainparams.GetConsensus().nPowTargetSpacing;            if (fPruneMode && (!(pindex->nStatus & BLOCK_HAVE_DATA) || pindex->nHeight <= ::ChainActive().Tip()->nHeight - nPrunedBlocksLikelyToHave))            {                LogPrint(BCLog::NET, " getblocks stopping, pruned or too old block at %d %s\n", pindex->nHeight, pindex->GetBlockHash().ToString());                break;            }            WITH_LOCK(pfrom.cs_inventory, pfrom.vInventoryBlockToSend.push_back(pindex->GetBlockHash()));            if (--nLimit <= 0)            {                // When this block is requested, we'll send an inv that'll                // trigger the peer to getblocks the next batch of inventory.                LogPrint(BCLog::NET, "  getblocks stopping at limit %d %s\n", pindex->nHeight, pindex->GetBlockHash().ToString());                pfrom.hashContinue = pindex->GetBlockHash();                break;            }        }        return;    }    if (msg_type == NetMsgType::GETBLOCKTXN) {        BlockTransactionsRequest req;        vRecv >> req;        std::shared_ptr<const CBlock> recent_block;        {            LOCK(cs_most_recent_block);            if (most_recent_block_hash == req.blockhash)                recent_block = most_recent_block;            // Unlock cs_most_recent_block to avoid cs_main lock inversion        }        if (recent_block) {            SendBlockTransactions(pfrom, *recent_block, req);            return;        }        {            LOCK(cs_main);            const CBlockIndex* pindex = LookupBlockIndex(req.blockhash);            if (!pindex || !(pindex->nStatus & BLOCK_HAVE_DATA)) {                LogPrint(BCLog::NET, "Peer %d sent us a getblocktxn for a block we don't have\n", pfrom.GetId());                return;            }            if (pindex->nHeight >= ::ChainActive().Height() - MAX_BLOCKTXN_DEPTH) {                CBlock block;                bool ret = ReadBlockFromDisk(block, pindex, m_chainparams.GetConsensus());                assert(ret);                SendBlockTransactions(pfrom, block, req);                return;            }        }        // If an older block is requested (should never happen in practice,        // but can happen in tests) send a block response instead of a        // blocktxn response. Sending a full block response instead of a        // small blocktxn response is preferable in the case where a peer        // might maliciously send lots of getblocktxn requests to trigger        // expensive disk reads, because it will require the peer to        // actually receive all the data read from disk over the network.        LogPrint(BCLog::NET, "Peer %d sent us a getblocktxn for a block > %i deep\n", pfrom.GetId(), MAX_BLOCKTXN_DEPTH);        CInv inv;        WITH_LOCK(cs_main, inv.type = State(pfrom.GetId())->fWantsCmpctWitness ? MSG_WITNESS_BLOCK : MSG_BLOCK);		WITH_LOCK(cs_main, inv.type = State(pfrom.GetId())->fWantsCmpctMWEB ? MSG_MWEB_BLOCK : inv.type);        inv.hash = req.blockhash;        WITH_LOCK(peer->m_getdata_requests_mutex, peer->m_getdata_requests.push_back(inv));        // The message processing loop will go around again (without pausing) and we'll respond then        return;    }    if (msg_type == NetMsgType::GETHEADERS) {        CBlockLocator locator;        uint256 hashStop;        vRecv >> locator >> hashStop;        if (locator.vHave.size() > MAX_LOCATOR_SZ) {            LogPrint(BCLog::NET, "getheaders locator size %lld > %d, disconnect peer=%d\n", locator.vHave.size(), MAX_LOCATOR_SZ, pfrom.GetId());            pfrom.fDisconnect = true;            return;        }        LOCK(cs_main);        if (::ChainstateActive().IsInitialBlockDownload() && !pfrom.HasPermission(PF_DOWNLOAD)) {            LogPrint(BCLog::NET, "Ignoring getheaders from peer=%d because node is in initial block download\n", pfrom.GetId());            return;        }        CNodeState *nodestate = State(pfrom.GetId());        const CBlockIndex* pindex = nullptr;        if (locator.IsNull())        {            // If locator is null, return the hashStop block            pindex = LookupBlockIndex(hashStop);            if (!pindex) {                return;            }            if (!BlockRequestAllowed(pindex, m_chainparams.GetConsensus())) {                LogPrint(BCLog::NET, "%s: ignoring request from peer=%i for old block header that isn't in the main chain\n", __func__, pfrom.GetId());                return;            }        }        else        {            // Find the last block the caller has in the main chain            pindex = FindForkInGlobalIndex(::ChainActive(), locator);            if (pindex)                pindex = ::ChainActive().Next(pindex);        }        // we must use CBlocks, as CBlockHeaders won't include the 0x00 nTx count at the end        std::vector<CBlock> vHeaders;        int nLimit = MAX_HEADERS_RESULTS;        LogPrint(BCLog::NET, "getheaders %d to %s from peer=%d\n", (pindex ? pindex->nHeight : -1), hashStop.IsNull() ? "end" : hashStop.ToString(), pfrom.GetId());        for (; pindex; pindex = ::ChainActive().Next(pindex))        {            vHeaders.push_back(pindex->GetBlockHeader());            if (--nLimit <= 0 || pindex->GetBlockHash() == hashStop)                break;        }        // pindex can be nullptr either if we sent ::ChainActive().Tip() OR        // if our peer has ::ChainActive().Tip() (and thus we are sending an empty        // headers message). In both cases it's safe to update        // pindexBestHeaderSent to be our tip.        //        // It is important that we simply reset the BestHeaderSent value here,        // and not max(BestHeaderSent, newHeaderSent). We might have announced        // the currently-being-connected tip using a compact block, which        // resulted in the peer sending a headers request, which we respond to        // without the new block. By resetting the BestHeaderSent, we ensure we        // will re-announce the new block via headers (or compact blocks again)        // in the SendMessages logic.        nodestate->pindexBestHeaderSent = pindex ? pindex : ::ChainActive().Tip();        m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::HEADERS, vHeaders));        return;    }    if (msg_type == NetMsgType::TX) {        // Stop processing the transaction early if        // 1) We are in blocks only mode and peer has no relay permission        // 2) This peer is a block-relay-only peer        if ((!g_relay_txes && !pfrom.HasPermission(PF_RELAY)) || (pfrom.m_tx_relay == nullptr))        {            LogPrint(BCLog::NET, "transaction sent in violation of protocol peer=%d\n", pfrom.GetId());            pfrom.fDisconnect = true;            return;        }        CTransactionRef ptx;        vRecv >> ptx;        const CTransaction& tx = *ptx;        const uint256& txid = ptx->GetHash();        const uint256& wtxid = ptx->GetWitnessHash();        LOCK2(cs_main, g_cs_orphans);        CNodeState* nodestate = State(pfrom.GetId());        const uint256& hash = nodestate->m_wtxid_relay ? wtxid : txid;        pfrom.AddKnownTx(hash);        if (nodestate->m_wtxid_relay && txid != wtxid) {            // Insert txid into filterInventoryKnown, even for            // wtxidrelay peers. This prevents re-adding of            // unconfirmed parents to the recently_announced            // filter, when a child tx is requested. See            // ProcessGetData().            pfrom.AddKnownTx(txid);        }        m_txrequest.ReceivedResponse(pfrom.GetId(), txid);        if (tx.HasWitness()) m_txrequest.ReceivedResponse(pfrom.GetId(), wtxid);        // We do the AlreadyHaveTx() check using wtxid, rather than txid - in the        // absence of witness malleation, this is strictly better, because the        // recent rejects filter may contain the wtxid but rarely contains        // the txid of a segwit transaction that has been rejected.        // In the presence of witness malleation, it's possible that by only        // doing the check with wtxid, we could overlook a transaction which        // was confirmed with a different witness, or exists in our mempool        // with a different witness, but this has limited downside:        // mempool validation does its own lookup of whether we have the txid        // already; and an adversary can already relay us old transactions        // (older than our recency filter) if trying to DoS us, without any need        // for witness malleation.        if (AlreadyHaveTx(GenTxid(/* is_wtxid=*/true, wtxid), m_mempool)) {            if (pfrom.HasPermission(PF_FORCERELAY)) {                // Always relay transactions received from peers with forcerelay                // permission, even if they were already in the mempool, allowing                // the node to function as a gateway for nodes hidden behind it.                if (!m_mempool.exists(tx.GetHash())) {                    LogPrintf("Not relaying non-mempool transaction %s from forcerelay peer=%d\n", tx.GetHash().ToString(), pfrom.GetId());                } else {                    LogPrintf("Force relaying tx %s from peer=%d\n", tx.GetHash().ToString(), pfrom.GetId());                    RelayTransaction(tx.GetHash(), tx.GetWitnessHash(), m_connman);                }            }            return;        }        TxValidationState state;        std::list<CTransactionRef> lRemovedTxn;        if (AcceptToMemoryPool(m_mempool, state, ptx, &lRemovedTxn, false /* bypass_limits */)) {            m_mempool.check(&::ChainstateActive().CoinsTip());            // As this version of the transaction was acceptable, we can forget about any            // requests for it.            m_txrequest.ForgetTxHash(tx.GetHash());            m_txrequest.ForgetTxHash(tx.GetWitnessHash());            RelayTransaction(tx.GetHash(), tx.GetWitnessHash(), m_connman);            for (unsigned int i = 0; i < tx.vout.size(); i++) {                auto it_by_prev = mapOrphanTransactionsByPrev.find(COutPoint(txid, i));                if (it_by_prev != mapOrphanTransactionsByPrev.end()) {                    for (const auto& elem : it_by_prev->second) {                        peer->m_orphan_work_set.insert(elem->first);                    }                }            }            pfrom.nLastTXTime = GetTime();            LogPrint(BCLog::MEMPOOL, "AcceptToMemoryPool: peer=%d: accepted %s (poolsz %u txn, %u kB)\n",                pfrom.GetId(),                tx.GetHash().ToString(),                m_mempool.size(), m_mempool.DynamicMemoryUsage() / 1000);            for (const CTransactionRef& removedTx : lRemovedTxn) {                AddToCompactExtraTransactions(removedTx);            }            // Recursively process any orphan transactions that depended on this one            ProcessOrphanTx(peer->m_orphan_work_set);        }        else if (state.GetResult() == TxValidationResult::TX_MISSING_INPUTS)        {            bool fRejectedParents = false; // It may be the case that the orphans parents have all been rejected            // Deduplicate parent txids, so that we don't have to loop over            // the same parent txid more than once down below.            std::vector<uint256> unique_parents;            unique_parents.reserve(tx.vin.size());            for (const CTxIn& txin : tx.vin) {                // We start with all parents, and then remove duplicates below.                unique_parents.push_back(txin.prevout.hash);            }            std::sort(unique_parents.begin(), unique_parents.end());            unique_parents.erase(std::unique(unique_parents.begin(), unique_parents.end()), unique_parents.end());            for (const uint256& parent_txid : unique_parents) {                if (recentRejects->contains(parent_txid)) {                    fRejectedParents = true;                    break;                }            }            if (!fRejectedParents) {                const auto current_time = GetTime<std::chrono::microseconds>();                for (const uint256& parent_txid : unique_parents) {                    // Here, we only have the txid (and not wtxid) of the                    // inputs, so we only request in txid mode, even for                    // wtxidrelay peers.                    // Eventually we should replace this with an improved                    // protocol for getting all unconfirmed parents.                    const GenTxid gtxid{/* is_wtxid=*/false, parent_txid};                    pfrom.AddKnownTx(parent_txid);                    if (!AlreadyHaveTx(gtxid, m_mempool)) AddTxAnnouncement(pfrom, gtxid, current_time);                }                AddOrphanTx(ptx, pfrom.GetId());                // Once added to the orphan pool, a tx is considered AlreadyHave, and we shouldn't request it anymore.                m_txrequest.ForgetTxHash(tx.GetHash());                m_txrequest.ForgetTxHash(tx.GetWitnessHash());                // DoS prevention: do not allow mapOrphanTransactions to grow unbounded (see CVE-2012-3789)                unsigned int nMaxOrphanTx = (unsigned int)std::max((int64_t)0, gArgs.GetArg("-maxorphantx", DEFAULT_MAX_ORPHAN_TRANSACTIONS));                unsigned int nEvicted = LimitOrphanTxSize(nMaxOrphanTx);                if (nEvicted > 0) {                    LogPrint(BCLog::MEMPOOL, "mapOrphan overflow, removed %u tx\n", nEvicted);                }            } else {                LogPrint(BCLog::MEMPOOL, "not keeping orphan with rejected parents %s\n",tx.GetHash().ToString());                // We will continue to reject this tx since it has rejected                // parents so avoid re-requesting it from other peers.                // Here we add both the txid and the wtxid, as we know that                // regardless of what witness is provided, we will not accept                // this, so we don't need to allow for redownload of this txid                // from any of our non-wtxidrelay peers.                recentRejects->insert(tx.GetHash());                recentRejects->insert(tx.GetWitnessHash());                m_txrequest.ForgetTxHash(tx.GetHash());                m_txrequest.ForgetTxHash(tx.GetWitnessHash());            }        } else {            if (state.GetResult() != TxValidationResult::TX_WITNESS_STRIPPED) {                // We can add the wtxid of this transaction to our reject filter.                // Do not add txids of witness transactions or witness-stripped                // transactions to the filter, as they can have been malleated;                // adding such txids to the reject filter would potentially                // interfere with relay of valid transactions from peers that                // do not support wtxid-based relay. See                // https://github.com/bitcoin/bitcoin/issues/8279 for details.                // We can remove this restriction (and always add wtxids to                // the filter even for witness stripped transactions) once                // wtxid-based relay is broadly deployed.                // See also comments in https://github.com/bitcoin/bitcoin/pull/18044#discussion_r443419034                // for concerns around weakening security of unupgraded nodes                // if we start doing this too early.                assert(recentRejects);                recentRejects->insert(tx.GetWitnessHash());                m_txrequest.ForgetTxHash(tx.GetWitnessHash());                // If the transaction failed for TX_INPUTS_NOT_STANDARD,                // then we know that the witness was irrelevant to the policy                // failure, since this check depends only on the txid                // (the scriptPubKey being spent is covered by the txid).                // Add the txid to the reject filter to prevent repeated                // processing of this transaction in the event that child                // transactions are later received (resulting in                // parent-fetching by txid via the orphan-handling logic).                if (state.GetResult() == TxValidationResult::TX_INPUTS_NOT_STANDARD && tx.GetWitnessHash() != tx.GetHash()) {                    recentRejects->insert(tx.GetHash());                    m_txrequest.ForgetTxHash(tx.GetHash());                }                if (RecursiveDynamicUsage(*ptx) < 100000) {                    AddToCompactExtraTransactions(ptx);                }            }        }        // If a tx has been detected by recentRejects, we will have reached        // this point and the tx will have been ignored. Because we haven't run        // the tx through AcceptToMemoryPool, we won't have computed a DoS        // score for it or determined exactly why we consider it invalid.        //        // This means we won't penalize any peer subsequently relaying a DoSy        // tx (even if we penalized the first peer who gave it to us) because        // we have to account for recentRejects showing false positives. In        // other words, we shouldn't penalize a peer if we aren't *sure* they        // submitted a DoSy tx.        //        // Note that recentRejects doesn't just record DoSy or invalid        // transactions, but any tx not accepted by the mempool, which may be        // due to node policy (vs. consensus). So we can't blanket penalize a        // peer simply for relaying a tx that our recentRejects has caught,        // regardless of false positives.        if (state.IsInvalid()) {            LogPrint(BCLog::MEMPOOLREJ, "%s from peer=%d was not accepted: %s\n", tx.GetHash().ToString(),                pfrom.GetId(),                state.ToString());            MaybePunishNodeForTx(pfrom.GetId(), state);        }        return;    }    if (msg_type == NetMsgType::CMPCTBLOCK)    {        // Ignore cmpctblock received while importing        if (fImporting || fReindex) {            LogPrint(BCLog::NET, "Unexpected cmpctblock message received from peer %d\n", pfrom.GetId());            return;        }		        {            LOCK(cs_main);            CBlockIndex* pTip = ::ChainActive().Tip();            assert(pTip);            if (!State(pfrom.GetId())->fWantsCmpctMWEB) {                vRecv.SetVersion(vRecv.GetVersion() | SERIALIZE_NO_MWEB);            }        }        CBlockHeaderAndShortTxIDs cmpctblock;        vRecv >> cmpctblock;        bool received_new_header = false;        {        LOCK(cs_main);        if (!LookupBlockIndex(cmpctblock.header.hashPrevBlock)) {            // Doesn't connect (or is genesis), instead of DoSing in AcceptBlockHeader, request deeper headers            if (!::ChainstateActive().IsInitialBlockDownload())                m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::GETHEADERS, ::ChainActive().GetLocator(pindexBestHeader), uint256()));            return;        }        if (!LookupBlockIndex(cmpctblock.header.GetHash())) {            received_new_header = true;        }        }        const CBlockIndex *pindex = nullptr;        BlockValidationState state;        if (!m_chainman.ProcessNewBlockHeaders({cmpctblock.header}, state, m_chainparams, &pindex)) {            if (state.IsInvalid()) {                MaybePunishNodeForBlock(pfrom.GetId(), state, /*via_compact_block*/ true, "invalid header via cmpctblock");                return;            }        }        // When we succeed in decoding a block's txids from a cmpctblock        // message we typically jump to the BLOCKTXN handling code, with a        // dummy (empty) BLOCKTXN message, to re-use the logic there in        // completing processing of the putative block (without cs_main).        bool fProcessBLOCKTXN = false;        CDataStream blockTxnMsg(SER_NETWORK, PROTOCOL_VERSION);        // If we end up treating this as a plain headers message, call that as well        // without cs_main.        bool fRevertToHeaderProcessing = false;        // Keep a CBlock for "optimistic" compactblock reconstructions (see        // below)        std::shared_ptr<CBlock> pblock = std::make_shared<CBlock>();        bool fBlockReconstructed = false;        {        LOCK2(cs_main, g_cs_orphans);        // If AcceptBlockHeader returned true, it set pindex        assert(pindex);        UpdateBlockAvailability(pfrom.GetId(), pindex->GetBlockHash());        CNodeState *nodestate = State(pfrom.GetId());        // If this was a new header with more work than our tip, update the        // peer's last block announcement time        if (received_new_header && pindex->nChainWork > ::ChainActive().Tip()->nChainWork) {            nodestate->m_last_block_announcement = GetTime();        }        std::map<uint256, std::pair<NodeId, std::list<QueuedBlock>::iterator> >::iterator blockInFlightIt = mapBlocksInFlight.find(pindex->GetBlockHash());        bool fAlreadyInFlight = blockInFlightIt != mapBlocksInFlight.end();        if (pindex->nStatus & BLOCK_HAVE_DATA) // Nothing to do here            return;        if (pindex->nChainWork <= ::ChainActive().Tip()->nChainWork || // We know something better                pindex->nTx != 0) { // We had this block at some point, but pruned it            if (fAlreadyInFlight) {                // We requested this block for some reason, but our mempool will probably be useless                // so we just grab the block via normal getdata                std::vector<CInv> vInv(1);                vInv[0] = CInv(MSG_BLOCK | GetFetchFlags(pfrom), cmpctblock.header.GetHash());                m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::GETDATA, vInv));            }            return;        }        // If we're not close to tip yet, give up and let parallel block fetch work its magic        if (!fAlreadyInFlight && !CanDirectFetch(m_chainparams.GetConsensus()))            return;        if (IsWitnessEnabled(pindex->pprev, m_chainparams.GetConsensus()) && !nodestate->fWantsCmpctWitness) {            // Don't bother trying to process compact blocks from v1 peers            // after segwit activates.            return;        }        if (IsMWEBEnabled(pindex->pprev, m_chainparams.GetConsensus()) && !nodestate->fWantsCmpctMWEB) {            // Don't bother trying to process compact blocks from v1/v2 peers            // after MWEB activates.            return;        }        // We want to be a bit conservative just to be extra careful about DoS        // possibilities in compact block processing...        if (pindex->nHeight <= ::ChainActive().Height() + 2) {            if ((!fAlreadyInFlight && nodestate->nBlocksInFlight < MAX_BLOCKS_IN_TRANSIT_PER_PEER) ||                 (fAlreadyInFlight && blockInFlightIt->second.first == pfrom.GetId())) {                std::list<QueuedBlock>::iterator* queuedBlockIt = nullptr;                if (!MarkBlockAsInFlight(m_mempool, pfrom.GetId(), pindex->GetBlockHash(), pindex, &queuedBlockIt)) {                    if (!(*queuedBlockIt)->partialBlock)                        (*queuedBlockIt)->partialBlock.reset(new PartiallyDownloadedBlock(&m_mempool, cmpctblock.mweb_block));                    else {                        // The block was already in flight using compact blocks from the same peer                        LogPrint(BCLog::NET, "Peer sent us compact block we were already syncing!\n");                        return;                    }                }                PartiallyDownloadedBlock& partialBlock = *(*queuedBlockIt)->partialBlock;                ReadStatus status = partialBlock.InitData(cmpctblock, vExtraTxnForCompact);                if (status == READ_STATUS_INVALID) {                    MarkBlockAsReceived(pindex->GetBlockHash(), pfrom.GetId()); // Reset in-flight state in case Misbehaving does not result in a disconnect                    Misbehaving(pfrom.GetId(), 100, "invalid compact block");                    return;                } else if (status == READ_STATUS_FAILED) {                    // Duplicate txindexes, the block is now in-flight, so just request it                    std::vector<CInv> vInv(1);                    vInv[0] = CInv(MSG_BLOCK | GetFetchFlags(pfrom), cmpctblock.header.GetHash());                    m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::GETDATA, vInv));                    return;                }                BlockTransactionsRequest req;                for (size_t i = 0; i < cmpctblock.BlockTxCount(); i++) {                    if (!partialBlock.IsTxAvailable(i))                        req.indexes.push_back(i);                }                if (req.indexes.empty()) {                    // Dirty hack to jump to BLOCKTXN code (TODO: move message handling into their own functions)                    BlockTransactions txn;                    txn.blockhash = cmpctblock.header.GetHash();                    blockTxnMsg << txn;                    fProcessBLOCKTXN = true;                } else {                    req.blockhash = pindex->GetBlockHash();                    m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::GETBLOCKTXN, req));                }            } else {                // This block is either already in flight from a different                // peer, or this peer has too many blocks outstanding to                // download from.                // Optimistically try to reconstruct anyway since we might be                // able to without any round trips.                PartiallyDownloadedBlock tempBlock(&m_mempool, cmpctblock.mweb_block);                ReadStatus status = tempBlock.InitData(cmpctblock, vExtraTxnForCompact);                if (status != READ_STATUS_OK) {                    // TODO: don't ignore failures                    return;                }                std::vector<CTransactionRef> dummy;                status = tempBlock.FillBlock(*pblock, dummy);                if (status == READ_STATUS_OK) {                    fBlockReconstructed = true;                }            }        } else {            if (fAlreadyInFlight) {                // We requested this block, but its far into the future, so our                // mempool will probably be useless - request the block normally                std::vector<CInv> vInv(1);                vInv[0] = CInv(MSG_BLOCK | GetFetchFlags(pfrom), cmpctblock.header.GetHash());                m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::GETDATA, vInv));                return;            } else {                // If this was an announce-cmpctblock, we want the same treatment as a header message                fRevertToHeaderProcessing = true;            }        }        } // cs_main        if (fProcessBLOCKTXN) {            return ProcessMessage(pfrom, NetMsgType::BLOCKTXN, blockTxnMsg, time_received, interruptMsgProc);        }        if (fRevertToHeaderProcessing) {            // Headers received from HB compact block peers are permitted to be            // relayed before full validation (see BIP 152), so we don't want to disconnect            // the peer if the header turns out to be for an invalid block.            // Note that if a peer tries to build on an invalid chain, that            // will be detected and the peer will be disconnected/discouraged.            return ProcessHeadersMessage(pfrom, {cmpctblock.header}, /*via_compact_block=*/true);        }        if (fBlockReconstructed) {            // If we got here, we were able to optimistically reconstruct a            // block that is in flight from some other peer.            {                LOCK(cs_main);                mapBlockSource.emplace(pblock->GetHash(), std::make_pair(pfrom.GetId(), false));            }            bool fNewBlock = false;            // Setting fForceProcessing to true means that we bypass some of            // our anti-DoS protections in AcceptBlock, which filters            // unrequested blocks that might be trying to waste our resources            // (eg disk space). Because we only try to reconstruct blocks when            // we're close to caught up (via the CanDirectFetch() requirement            // above, combined with the behavior of not requesting blocks until            // we have a chain with at least nMinimumChainWork), and we ignore            // compact blocks with less work than our tip, it is safe to treat            // reconstructed compact blocks as having been requested.            m_chainman.ProcessNewBlock(m_chainparams, pblock, /*fForceProcessing=*/true, &fNewBlock);            if (fNewBlock) {                pfrom.nLastBlockTime = GetTime();            } else {                LOCK(cs_main);                mapBlockSource.erase(pblock->GetHash());            }            LOCK(cs_main); // hold cs_main for CBlockIndex::IsValid()            if (pindex->IsValid(BLOCK_VALID_TRANSACTIONS)) {                // Clear download state for this block, which is in                // process from some other peer.  We do this after calling                // ProcessNewBlock so that a malleated cmpctblock announcement                // can't be used to interfere with block relay.                MarkBlockAsReceived(pblock->GetHash(), nullopt);            }        }        return;    }    if (msg_type == NetMsgType::BLOCKTXN)    {        // Ignore blocktxn received while importing        if (fImporting || fReindex) {            LogPrint(BCLog::NET, "Unexpected blocktxn message received from peer %d\n", pfrom.GetId());            return;        }        BlockTransactions resp;        vRecv >> resp;        std::shared_ptr<CBlock> pblock = std::make_shared<CBlock>();        bool fBlockRead = false;        {            LOCK(cs_main);            std::map<uint256, std::pair<NodeId, std::list<QueuedBlock>::iterator> >::iterator it = mapBlocksInFlight.find(resp.blockhash);            if (it == mapBlocksInFlight.end() || !it->second.second->partialBlock ||                    it->second.first != pfrom.GetId()) {                LogPrint(BCLog::NET, "Peer %d sent us block transactions for block we weren't expecting\n", pfrom.GetId());                return;            }            PartiallyDownloadedBlock& partialBlock = *it->second.second->partialBlock;            ReadStatus status = partialBlock.FillBlock(*pblock, resp.txn);            if (status == READ_STATUS_INVALID) {                MarkBlockAsReceived(resp.blockhash, pfrom.GetId()); // Reset in-flight state in case Misbehaving does not result in a disconnect                Misbehaving(pfrom.GetId(), 100, "invalid compact block/non-matching block transactions");                return;            } else if (status == READ_STATUS_FAILED) {                // Might have collided, fall back to getdata now :(                std::vector<CInv> invs;                invs.push_back(CInv(MSG_BLOCK | GetFetchFlags(pfrom), resp.blockhash));                m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::GETDATA, invs));            } else {                // Block is either okay, or possibly we received                // READ_STATUS_CHECKBLOCK_FAILED.                // Note that CheckBlock can only fail for one of a few reasons:                // 1. bad-proof-of-work (impossible here, because we've already                //    accepted the header)                // 2. merkleroot doesn't match the transactions given (already                //    caught in FillBlock with READ_STATUS_FAILED, so                //    impossible here)                // 3. the block is otherwise invalid (eg invalid coinbase,                //    block is too big, too many legacy sigops, etc).                // So if CheckBlock failed, #3 is the only possibility.                // Under BIP 152, we don't discourage the peer unless proof of work is                // invalid (we don't require all the stateless checks to have                // been run).  This is handled below, so just treat this as                // though the block was successfully read, and rely on the                // handling in ProcessNewBlock to ensure the block index is                // updated, etc.                MarkBlockAsReceived(resp.blockhash, pfrom.GetId()); // it is now an empty pointer                fBlockRead = true;                // mapBlockSource is used for potentially punishing peers and                // updating which peers send us compact blocks, so the race                // between here and cs_main in ProcessNewBlock is fine.                // BIP 152 permits peers to relay compact blocks after validating                // the header only; we should not punish peers if the block turns                // out to be invalid.                mapBlockSource.emplace(resp.blockhash, std::make_pair(pfrom.GetId(), false));            }        } // Don't hold cs_main when we call into ProcessNewBlock        if (fBlockRead) {            bool fNewBlock = false;            // Since we requested this block (it was in mapBlocksInFlight), force it to be processed,            // even if it would not be a candidate for new tip (missing previous block, chain not long enough, etc)            // This bypasses some anti-DoS logic in AcceptBlock (eg to prevent            // disk-space attacks), but this should be safe due to the            // protections in the compact block handler -- see related comment            // in compact block optimistic reconstruction handling.            m_chainman.ProcessNewBlock(m_chainparams, pblock, /*fForceProcessing=*/true, &fNewBlock);            if (fNewBlock) {                pfrom.nLastBlockTime = GetTime();            } else {                LOCK(cs_main);                mapBlockSource.erase(pblock->GetHash());            }        }        return;    }    if (msg_type == NetMsgType::HEADERS)    {        // Ignore headers received while importing        if (fImporting || fReindex) {            LogPrint(BCLog::NET, "Unexpected headers message received from peer %d\n", pfrom.GetId());            return;        }        std::vector<CBlockHeader> headers;        // Bypass the normal CBlock deserialization, as we don't want to risk deserializing 2000 full blocks.        unsigned int nCount = ReadCompactSize(vRecv);        if (nCount > MAX_HEADERS_RESULTS) {            Misbehaving(pfrom.GetId(), 20, strprintf("headers message size = %u", nCount));            return;        }        headers.resize(nCount);        for (unsigned int n = 0; n < nCount; n++) {            vRecv >> headers[n];            ReadCompactSize(vRecv); // ignore tx count; assume it is 0.        }        return ProcessHeadersMessage(pfrom, headers, /*via_compact_block=*/false);    }    if (msg_type == NetMsgType::BLOCK)    {        // Ignore block received while importing        if (fImporting || fReindex) {            LogPrint(BCLog::NET, "Unexpected block message received from peer %d\n", pfrom.GetId());            return;        }        std::shared_ptr<CBlock> pblock = std::make_shared<CBlock>();        vRecv >> *pblock;        LogPrint(BCLog::NET, "received block %s peer=%d\n", pblock->GetHash().ToString(), pfrom.GetId());        bool forceProcessing = false;        const uint256 hash(pblock->GetHash());        {            LOCK(cs_main);            // Also always process if we requested the block explicitly, as we may            // need it even though it is not a candidate for a new best tip.            forceProcessing |= MarkBlockAsReceived(hash, pfrom.GetId());            // mapBlockSource is only used for punishing peers and setting            // which peers send us compact blocks, so the race between here and            // cs_main in ProcessNewBlock is fine.            mapBlockSource.emplace(hash, std::make_pair(pfrom.GetId(), true));        }        bool fNewBlock = false;        m_chainman.ProcessNewBlock(m_chainparams, pblock, forceProcessing, &fNewBlock);        if (fNewBlock) {            pfrom.nLastBlockTime = GetTime();        } else {            LOCK(cs_main);            mapBlockSource.erase(pblock->GetHash());        }        return;    }    if (msg_type == NetMsgType::GETADDR) {        // This asymmetric behavior for inbound and outbound connections was introduced        // to prevent a fingerprinting attack: an attacker can send specific fake addresses        // to users' AddrMan and later request them by sending getaddr messages.        // Making nodes which are behind NAT and can only make outgoing connections ignore        // the getaddr message mitigates the attack.        if (!pfrom.IsInboundConn()) {            LogPrint(BCLog::NET, "Ignoring \"getaddr\" from %s connection. peer=%d\n", pfrom.ConnectionTypeAsString(), pfrom.GetId());            return;        }        // Only send one GetAddr response per connection to reduce resource waste        //  and discourage addr stamping of INV announcements.        if (pfrom.fSentAddr) {            LogPrint(BCLog::NET, "Ignoring repeated \"getaddr\". peer=%d\n", pfrom.GetId());            return;        }        pfrom.fSentAddr = true;        pfrom.vAddrToSend.clear();        std::vector<CAddress> vAddr;        if (pfrom.HasPermission(PF_ADDR)) {            vAddr = m_connman.GetAddresses(MAX_ADDR_TO_SEND, MAX_PCT_ADDR_TO_SEND);        } else {            vAddr = m_connman.GetAddresses(pfrom, MAX_ADDR_TO_SEND, MAX_PCT_ADDR_TO_SEND);        }        FastRandomContext insecure_rand;        for (const CAddress &addr : vAddr) {            pfrom.PushAddress(addr, insecure_rand);        }        return;    }    if (msg_type == NetMsgType::MEMPOOL) {        if (!(pfrom.GetLocalServices() & NODE_BLOOM) && !pfrom.HasPermission(PF_MEMPOOL))        {            if (!pfrom.HasPermission(PF_NOBAN))            {                LogPrint(BCLog::NET, "mempool request with bloom filters disabled, disconnect peer=%d\n", pfrom.GetId());                pfrom.fDisconnect = true;            }            return;        }        if (m_connman.OutboundTargetReached(false) && !pfrom.HasPermission(PF_MEMPOOL))        {            if (!pfrom.HasPermission(PF_NOBAN))            {                LogPrint(BCLog::NET, "mempool request with bandwidth limit reached, disconnect peer=%d\n", pfrom.GetId());                pfrom.fDisconnect = true;            }            return;        }        if (pfrom.m_tx_relay != nullptr) {            LOCK(pfrom.m_tx_relay->cs_tx_inventory);            pfrom.m_tx_relay->fSendMempool = true;        }        return;    }    if (msg_type == NetMsgType::PING) {        if (pfrom.GetCommonVersion() > BIP0031_VERSION) {            uint64_t nonce = 0;            vRecv >> nonce;            // Echo the message back with the nonce. This allows for two useful features:            //            // 1) A remote node can quickly check if the connection is operational            // 2) Remote nodes can measure the latency of the network thread. If this node            //    is overloaded it won't respond to pings quickly and the remote node can            //    avoid sending us more work, like chain download requests.            //            // The nonce stops the remote getting confused between different pings: without            // it, if the remote node sends a ping once per second and this node takes 5            // seconds to respond to each, the 5th ping the remote sends would appear to            // return very quickly.            m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::PONG, nonce));        }        return;    }    if (msg_type == NetMsgType::PONG) {        const auto ping_end = time_received;        uint64_t nonce = 0;        size_t nAvail = vRecv.in_avail();        bool bPingFinished = false;        std::string sProblem;        if (nAvail >= sizeof(nonce)) {            vRecv >> nonce;            // Only process pong message if there is an outstanding ping (old ping without nonce should never pong)            if (pfrom.nPingNonceSent != 0) {                if (nonce == pfrom.nPingNonceSent) {                    // Matching pong received, this ping is no longer outstanding                    bPingFinished = true;                    const auto ping_time = ping_end - pfrom.m_ping_start.load();                    if (ping_time.count() >= 0) {                        // Successful ping time measurement, replace previous                        pfrom.nPingUsecTime = count_microseconds(ping_time);                        pfrom.nMinPingUsecTime = std::min(pfrom.nMinPingUsecTime.load(), count_microseconds(ping_time));                    } else {                        // This should never happen                        sProblem = "Timing mishap";                    }                } else {                    // Nonce mismatches are normal when pings are overlapping                    sProblem = "Nonce mismatch";                    if (nonce == 0) {                        // This is most likely a bug in another implementation somewhere; cancel this ping                        bPingFinished = true;                        sProblem = "Nonce zero";                    }                }            } else {                sProblem = "Unsolicited pong without ping";            }        } else {            // This is most likely a bug in another implementation somewhere; cancel this ping            bPingFinished = true;            sProblem = "Short payload";        }        if (!(sProblem.empty())) {            LogPrint(BCLog::NET, "pong peer=%d: %s, %x expected, %x received, %u bytes\n",                pfrom.GetId(),                sProblem,                pfrom.nPingNonceSent,                nonce,                nAvail);        }        if (bPingFinished) {            pfrom.nPingNonceSent = 0;        }        return;    }    if (msg_type == NetMsgType::FILTERLOAD) {        if (!(pfrom.GetLocalServices() & NODE_BLOOM)) {            pfrom.fDisconnect = true;            return;        }        CBloomFilter filter;        vRecv >> filter;        if (!filter.IsWithinSizeConstraints())        {            // There is no excuse for sending a too-large filter            Misbehaving(pfrom.GetId(), 100, "too-large bloom filter");        }        else if (pfrom.m_tx_relay != nullptr)        {            LOCK(pfrom.m_tx_relay->cs_filter);            pfrom.m_tx_relay->pfilter.reset(new CBloomFilter(filter));            pfrom.m_tx_relay->fRelayTxes = true;        }        return;    }    if (msg_type == NetMsgType::FILTERADD) {        if (!(pfrom.GetLocalServices() & NODE_BLOOM)) {            pfrom.fDisconnect = true;            return;        }        std::vector<unsigned char> vData;        vRecv >> vData;        // Nodes must NEVER send a data item > 520 bytes (the max size for a script data object,        // and thus, the maximum size any matched object can have) in a filteradd message        bool bad = false;        if (vData.size() > MAX_SCRIPT_ELEMENT_SIZE) {            bad = true;        } else if (pfrom.m_tx_relay != nullptr) {            LOCK(pfrom.m_tx_relay->cs_filter);            if (pfrom.m_tx_relay->pfilter) {                pfrom.m_tx_relay->pfilter->insert(vData);            } else {                bad = true;            }        }        if (bad) {            Misbehaving(pfrom.GetId(), 100, "bad filteradd message");        }        return;    }    if (msg_type == NetMsgType::FILTERCLEAR) {        if (!(pfrom.GetLocalServices() & NODE_BLOOM)) {            pfrom.fDisconnect = true;            return;        }        if (pfrom.m_tx_relay == nullptr) {            return;        }        LOCK(pfrom.m_tx_relay->cs_filter);        pfrom.m_tx_relay->pfilter = nullptr;        pfrom.m_tx_relay->fRelayTxes = true;        return;    }    if (msg_type == NetMsgType::FEEFILTER) {        CAmount newFeeFilter = 0;        vRecv >> newFeeFilter;        if (MoneyRange(newFeeFilter)) {            if (pfrom.m_tx_relay != nullptr) {                LOCK(pfrom.m_tx_relay->cs_feeFilter);                pfrom.m_tx_relay->minFeeFilter = newFeeFilter;            }            LogPrint(BCLog::NET, "received: feefilter of %s from peer=%d\n", CFeeRate(newFeeFilter).ToString(), pfrom.GetId());        }        return;    }    if (msg_type == NetMsgType::GETCFILTERS) {        ProcessGetCFilters(pfrom, vRecv, m_chainparams, m_connman);        return;    }    if (msg_type == NetMsgType::GETCFHEADERS) {        ProcessGetCFHeaders(pfrom, vRecv, m_chainparams, m_connman);        return;    }    if (msg_type == NetMsgType::GETCFCHECKPT) {        ProcessGetCFCheckPt(pfrom, vRecv, m_chainparams, m_connman);        return;    }    if (msg_type == NetMsgType::NOTFOUND) {        std::vector<CInv> vInv;        vRecv >> vInv;        if (vInv.size() <= MAX_PEER_TX_ANNOUNCEMENTS + MAX_BLOCKS_IN_TRANSIT_PER_PEER) {            LOCK(::cs_main);            for (CInv &inv : vInv) {                if (inv.IsGenTxMsg()) {                    // If we receive a NOTFOUND message for a tx we requested, mark the announcement for it as                    // completed in TxRequestTracker.                    m_txrequest.ReceivedResponse(pfrom.GetId(), inv.hash);                }            }        }        return;    }    if (msg_type == NetMsgType::GETMWEBUTXOS) {        GetMWEBUTXOsMsg get_utxos;        vRecv >> get_utxos;        ProcessGetMWEBUTXOs(pfrom, m_chainman, m_chainparams, m_connman, get_utxos);        return;    }    // Ignore unknown commands for extensibility    LogPrint(BCLog::NET, "Unknown command \"%s\" from peer=%d\n", SanitizeString(msg_type), pfrom.GetId());    return;}bool PeerManager::MaybeDiscourageAndDisconnect(CNode& pnode){    const NodeId peer_id{pnode.GetId()};    PeerRef peer = GetPeerRef(peer_id);    if (peer == nullptr) return false;    {        LOCK(peer->m_misbehavior_mutex);        // There's nothing to do if the m_should_discourage flag isn't set        if (!peer->m_should_discourage) return false;        peer->m_should_discourage = false;    } // peer.m_misbehavior_mutex    if (pnode.HasPermission(PF_NOBAN)) {        // We never disconnect or discourage peers for bad behavior if they have the NOBAN permission flag        LogPrintf("Warning: not punishing noban peer %d!\n", peer_id);        return false;    }    if (pnode.IsManualConn()) {        // We never disconnect or discourage manual peers for bad behavior        LogPrintf("Warning: not punishing manually connected peer %d!\n", peer_id);        return false;    }    if (pnode.addr.IsLocal()) {        // We disconnect local peers for bad behavior but don't discourage (since that would discourage        // all peers on the same local address)        LogPrintf("Warning: disconnecting but not discouraging local peer %d!\n", peer_id);        pnode.fDisconnect = true;        return true;    }    // Normal case: Disconnect the peer and discourage all nodes sharing the address    LogPrintf("Disconnecting and discouraging peer %d!\n", peer_id);    if (m_banman) m_banman->Discourage(pnode.addr);    m_connman.DisconnectNode(pnode.addr);    return true;}bool PeerManager::ProcessMessages(CNode* pfrom, std::atomic<bool>& interruptMsgProc){    bool fMoreWork = false;    PeerRef peer = GetPeerRef(pfrom->GetId());    if (peer == nullptr) return false;    {        LOCK(peer->m_getdata_requests_mutex);        if (!peer->m_getdata_requests.empty()) {            ProcessGetData(*pfrom, *peer, m_chainman, m_chainparams, m_connman, m_mempool, interruptMsgProc);        }    }    {        LOCK2(cs_main, g_cs_orphans);        if (!peer->m_orphan_work_set.empty()) {            ProcessOrphanTx(peer->m_orphan_work_set);        }    }    if (pfrom->fDisconnect)        return false;    // this maintains the order of responses    // and prevents m_getdata_requests to grow unbounded    {        LOCK(peer->m_getdata_requests_mutex);        if (!peer->m_getdata_requests.empty()) return true;    }    {        LOCK(g_cs_orphans);        if (!peer->m_orphan_work_set.empty()) return true;    }    // Don't bother if send buffer is too full to respond anyway    if (pfrom->fPauseSend)        return false;    std::list<CNetMessage> msgs;    {        LOCK(pfrom->cs_vProcessMsg);        if (pfrom->vProcessMsg.empty())            return false;        // Just take one message        msgs.splice(msgs.begin(), pfrom->vProcessMsg, pfrom->vProcessMsg.begin());        pfrom->nProcessQueueSize -= msgs.front().m_raw_message_size;        pfrom->fPauseRecv = pfrom->nProcessQueueSize > m_connman.GetReceiveFloodSize();        fMoreWork = !pfrom->vProcessMsg.empty();    }    CNetMessage& msg(msgs.front());    msg.SetVersion(pfrom->GetCommonVersion());    const std::string& msg_type = msg.m_command;    // Message size    unsigned int nMessageSize = msg.m_message_size;    try {        ProcessMessage(*pfrom, msg_type, msg.m_recv, msg.m_time, interruptMsgProc);        if (interruptMsgProc) return false;        {            LOCK(peer->m_getdata_requests_mutex);            if (!peer->m_getdata_requests.empty()) fMoreWork = true;        }    } catch (const std::exception& e) {        LogPrint(BCLog::NET, "%s(%s, %u bytes): Exception '%s' (%s) caught\n", __func__, SanitizeString(msg_type), nMessageSize, e.what(), typeid(e).name());    } catch (...) {        LogPrint(BCLog::NET, "%s(%s, %u bytes): Unknown exception caught\n", __func__, SanitizeString(msg_type), nMessageSize);    }    return fMoreWork;}void PeerManager::ConsiderEviction(CNode& pto, int64_t time_in_seconds){    AssertLockHeld(cs_main);    CNodeState &state = *State(pto.GetId());    const CNetMsgMaker msgMaker(pto.GetCommonVersion());    if (!state.m_chain_sync.m_protect && pto.IsOutboundOrBlockRelayConn() && state.fSyncStarted) {        // This is an outbound peer subject to disconnection if they don't        // announce a block with as much work as the current tip within        // CHAIN_SYNC_TIMEOUT + HEADERS_RESPONSE_TIME seconds (note: if        // their chain has more work than ours, we should sync to it,        // unless it's invalid, in which case we should find that out and        // disconnect from them elsewhere).        if (state.pindexBestKnownBlock != nullptr && state.pindexBestKnownBlock->nChainWork >= ::ChainActive().Tip()->nChainWork) {            if (state.m_chain_sync.m_timeout != 0) {                state.m_chain_sync.m_timeout = 0;                state.m_chain_sync.m_work_header = nullptr;                state.m_chain_sync.m_sent_getheaders = false;            }        } else if (state.m_chain_sync.m_timeout == 0 || (state.m_chain_sync.m_work_header != nullptr && state.pindexBestKnownBlock != nullptr && state.pindexBestKnownBlock->nChainWork >= state.m_chain_sync.m_work_header->nChainWork)) {            // Our best block known by this peer is behind our tip, and we're either noticing            // that for the first time, OR this peer was able to catch up to some earlier point            // where we checked against our tip.            // Either way, set a new timeout based on current tip.            state.m_chain_sync.m_timeout = time_in_seconds + CHAIN_SYNC_TIMEOUT;            state.m_chain_sync.m_work_header = ::ChainActive().Tip();            state.m_chain_sync.m_sent_getheaders = false;        } else if (state.m_chain_sync.m_timeout > 0 && time_in_seconds > state.m_chain_sync.m_timeout) {            // No evidence yet that our peer has synced to a chain with work equal to that            // of our tip, when we first detected it was behind. Send a single getheaders            // message to give the peer a chance to update us.            if (state.m_chain_sync.m_sent_getheaders) {                // They've run out of time to catch up!                LogPrintf("Disconnecting outbound peer %d for old chain, best known block = %s\n", pto.GetId(), state.pindexBestKnownBlock != nullptr ? state.pindexBestKnownBlock->GetBlockHash().ToString() : "<none>");                pto.fDisconnect = true;            } else {                assert(state.m_chain_sync.m_work_header);                LogPrint(BCLog::NET, "sending getheaders to outbound peer=%d to verify chain work (current best known block:%s, benchmark blockhash: %s)\n", pto.GetId(), state.pindexBestKnownBlock != nullptr ? state.pindexBestKnownBlock->GetBlockHash().ToString() : "<none>", state.m_chain_sync.m_work_header->GetBlockHash().ToString());                m_connman.PushMessage(&pto, msgMaker.Make(NetMsgType::GETHEADERS, ::ChainActive().GetLocator(state.m_chain_sync.m_work_header->pprev), uint256()));                state.m_chain_sync.m_sent_getheaders = true;                constexpr int64_t HEADERS_RESPONSE_TIME = 120; // 2 minutes                // Bump the timeout to allow a response, which could clear the timeout                // (if the response shows the peer has synced), reset the timeout (if                // the peer syncs to the required work but not to our tip), or result                // in disconnect (if we advance to the timeout and pindexBestKnownBlock                // has not sufficiently progressed)                state.m_chain_sync.m_timeout = time_in_seconds + HEADERS_RESPONSE_TIME;            }        }    }}void PeerManager::EvictExtraOutboundPeers(int64_t time_in_seconds){    // Check whether we have too many outbound peers    int extra_peers = m_connman.GetExtraOutboundCount();    if (extra_peers > 0) {        // If we have more outbound peers than we target, disconnect one.        // Pick the outbound peer that least recently announced        // us a new block, with ties broken by choosing the more recent        // connection (higher node id)        NodeId worst_peer = -1;        int64_t oldest_block_announcement = std::numeric_limits<int64_t>::max();        m_connman.ForEachNode([&](CNode* pnode) EXCLUSIVE_LOCKS_REQUIRED(::cs_main) {            AssertLockHeld(::cs_main);            // Ignore non-outbound peers, or nodes marked for disconnect already            if (!pnode->IsOutboundOrBlockRelayConn() || pnode->fDisconnect) return;            CNodeState *state = State(pnode->GetId());            if (state == nullptr) return; // shouldn't be possible, but just in case            // Don't evict our protected peers            if (state->m_chain_sync.m_protect) return;            // Don't evict our block-relay-only peers.            if (pnode->m_tx_relay == nullptr) return;            if (state->m_last_block_announcement < oldest_block_announcement || (state->m_last_block_announcement == oldest_block_announcement && pnode->GetId() > worst_peer)) {                worst_peer = pnode->GetId();                oldest_block_announcement = state->m_last_block_announcement;            }        });        if (worst_peer != -1) {            bool disconnected = m_connman.ForNode(worst_peer, [&](CNode* pnode) EXCLUSIVE_LOCKS_REQUIRED(::cs_main) {                AssertLockHeld(::cs_main);                // Only disconnect a peer that has been connected to us for                // some reasonable fraction of our check-frequency, to give                // it time for new information to have arrived.                // Also don't disconnect any peer we're trying to download a                // block from.                CNodeState &state = *State(pnode->GetId());                if (time_in_seconds - pnode->nTimeConnected > MINIMUM_CONNECT_TIME && state.nBlocksInFlight == 0) {                    LogPrint(BCLog::NET, "disconnecting extra outbound peer=%d (last block announcement received at time %d)\n", pnode->GetId(), oldest_block_announcement);                    pnode->fDisconnect = true;                    return true;                } else {                    LogPrint(BCLog::NET, "keeping outbound peer=%d chosen for eviction (connect time: %d, blocks_in_flight: %d)\n", pnode->GetId(), pnode->nTimeConnected, state.nBlocksInFlight);                    return false;                }            });            if (disconnected) {                // If we disconnected an extra peer, that means we successfully                // connected to at least one peer after the last time we                // detected a stale tip. Don't try any more extra peers until                // we next detect a stale tip, to limit the load we put on the                // network from these extra connections.                m_connman.SetTryNewOutboundPeer(false);            }        }    }}void PeerManager::CheckForStaleTipAndEvictPeers(){    LOCK(cs_main);    int64_t time_in_seconds = GetTime();    EvictExtraOutboundPeers(time_in_seconds);    if (time_in_seconds > m_stale_tip_check_time) {        // Check whether our tip is stale, and if so, allow using an extra        // outbound peer        if (!fImporting && !fReindex && m_connman.GetNetworkActive() && m_connman.GetUseAddrmanOutgoing() && TipMayBeStale(m_chainparams.GetConsensus())) {            LogPrintf("Potential stale tip detected, will try using extra outbound peer (last tip update: %d seconds ago)\n", time_in_seconds - g_last_tip_update);            m_connman.SetTryNewOutboundPeer(true);        } else if (m_connman.GetTryNewOutboundPeer()) {            m_connman.SetTryNewOutboundPeer(false);        }        m_stale_tip_check_time = time_in_seconds + STALE_CHECK_INTERVAL;    }}namespace {class CompareInvMempoolOrder{    CTxMemPool *mp;    bool m_wtxid_relay;public:    explicit CompareInvMempoolOrder(CTxMemPool *_mempool, bool use_wtxid)    {        mp = _mempool;        m_wtxid_relay = use_wtxid;    }    bool operator()(std::set<uint256>::iterator a, std::set<uint256>::iterator b)    {        /* As std::make_heap produces a max-heap, we want the entries with the         * fewest ancestors/highest fee to sort later. */        return mp->CompareDepthAndScore(*b, *a, m_wtxid_relay);    }};}bool PeerManager::SendMessages(CNode* pto){    const Consensus::Params& consensusParams = m_chainparams.GetConsensus();    // We must call MaybeDiscourageAndDisconnect first, to ensure that we'll    // disconnect misbehaving peers even before the version handshake is complete.    if (MaybeDiscourageAndDisconnect(*pto)) return true;    // Don't send anything until the version handshake is complete    if (!pto->fSuccessfullyConnected || pto->fDisconnect)        return true;    // If we get here, the outgoing message serialization version is set and can't change.    const CNetMsgMaker msgMaker(pto->GetCommonVersion());    //    // Message: ping    //    bool pingSend = false;    if (pto->fPingQueued) {        // RPC ping request by user        pingSend = true;    }    if (pto->nPingNonceSent == 0 && pto->m_ping_start.load() + PING_INTERVAL < GetTime<std::chrono::microseconds>()) {        // Ping automatically sent as a latency probe & keepalive.        pingSend = true;    }    if (pingSend) {        uint64_t nonce = 0;        while (nonce == 0) {            GetRandBytes((unsigned char*)&nonce, sizeof(nonce));        }        pto->fPingQueued = false;        pto->m_ping_start = GetTime<std::chrono::microseconds>();        if (pto->GetCommonVersion() > BIP0031_VERSION) {            pto->nPingNonceSent = nonce;            m_connman.PushMessage(pto, msgMaker.Make(NetMsgType::PING, nonce));        } else {            // Peer is too old to support ping command with nonce, pong will never arrive.            pto->nPingNonceSent = 0;            m_connman.PushMessage(pto, msgMaker.Make(NetMsgType::PING));        }    }    {        LOCK(cs_main);        CNodeState &state = *State(pto->GetId());        // Address refresh broadcast        auto current_time = GetTime<std::chrono::microseconds>();        if (pto->RelayAddrsWithConn() && !::ChainstateActive().IsInitialBlockDownload() && pto->m_next_local_addr_send < current_time) {            AdvertiseLocal(pto);            pto->m_next_local_addr_send = PoissonNextSend(current_time, AVG_LOCAL_ADDRESS_BROADCAST_INTERVAL);        }        //        // Message: addr        //        if (pto->RelayAddrsWithConn() && pto->m_next_addr_send < current_time) {            pto->m_next_addr_send = PoissonNextSend(current_time, AVG_ADDRESS_BROADCAST_INTERVAL);            std::vector<CAddress> vAddr;            vAddr.reserve(pto->vAddrToSend.size());            assert(pto->m_addr_known);            const char* msg_type;            int make_flags;            if (pto->m_wants_addrv2) {                msg_type = NetMsgType::ADDRV2;                make_flags = ADDRV2_FORMAT;            } else {                msg_type = NetMsgType::ADDR;                make_flags = 0;            }            for (const CAddress& addr : pto->vAddrToSend)            {                if (!pto->m_addr_known->contains(addr.GetKey()))                {                    pto->m_addr_known->insert(addr.GetKey());                    vAddr.push_back(addr);                    // receiver rejects addr messages larger than MAX_ADDR_TO_SEND                    if (vAddr.size() >= MAX_ADDR_TO_SEND)                    {                        m_connman.PushMessage(pto, msgMaker.Make(make_flags, msg_type, vAddr));                        vAddr.clear();                    }                }            }            pto->vAddrToSend.clear();            if (!vAddr.empty())                m_connman.PushMessage(pto, msgMaker.Make(make_flags, msg_type, vAddr));            // we only send the big addr message once            if (pto->vAddrToSend.capacity() > 40)                pto->vAddrToSend.shrink_to_fit();        }        // Start block sync        if (pindexBestHeader == nullptr)            pindexBestHeader = ::ChainActive().Tip();        bool fFetch = state.fPreferredDownload || (nPreferredDownload == 0 && !pto->fClient && !pto->IsAddrFetchConn()); // Download if this is a nice peer, or we have no nice peers and this one might do.        if (!state.fSyncStarted && !pto->fClient && !fImporting && !fReindex) {            // Only actively request headers from a single peer, unless we're close to today.            if ((nSyncStarted == 0 && fFetch) || pindexBestHeader->GetBlockTime() > GetAdjustedTime() - 24 * 60 * 60) {                state.fSyncStarted = true;                state.nHeadersSyncTimeout = count_microseconds(current_time) + HEADERS_DOWNLOAD_TIMEOUT_BASE + HEADERS_DOWNLOAD_TIMEOUT_PER_HEADER * (GetAdjustedTime() - pindexBestHeader->GetBlockTime())/(consensusParams.nPowTargetSpacing);                nSyncStarted++;                const CBlockIndex *pindexStart = pindexBestHeader;                /* If possible, start at the block preceding the currently                   best known header.  This ensures that we always get a                   non-empty list of headers back as long as the peer                   is up-to-date.  With a non-empty response, we can initialise                   the peer's known best block.  This wouldn't be possible                   if we requested starting at pindexBestHeader and                   got back an empty response.  */                if (pindexStart->pprev)                    pindexStart = pindexStart->pprev;                LogPrint(BCLog::NET, "initial getheaders (%d) to peer=%d (startheight:%d)\n", pindexStart->nHeight, pto->GetId(), pto->nStartingHeight);                m_connman.PushMessage(pto, msgMaker.Make(NetMsgType::GETHEADERS, ::ChainActive().GetLocator(pindexStart), uint256()));            }        }        //        // Try sending block announcements via headers        //        {            // If we have less than MAX_BLOCKS_TO_ANNOUNCE in our            // list of block hashes we're relaying, and our peer wants            // headers announcements, then find the first header            // not yet known to our peer but would connect, and send.            // If no header would connect, or if we have too many            // blocks, or if the peer doesn't want headers, just            // add all to the inv queue.            LOCK(pto->cs_inventory);            std::vector<CBlock> vHeaders;            bool fRevertToInv = ((!state.fPreferHeaders &&                                 (!state.fPreferHeaderAndIDs || pto->vBlockHashesToAnnounce.size() > 1)) ||                                pto->vBlockHashesToAnnounce.size() > MAX_BLOCKS_TO_ANNOUNCE);            const CBlockIndex *pBestIndex = nullptr; // last header queued for delivery            ProcessBlockAvailability(pto->GetId()); // ensure pindexBestKnownBlock is up-to-date            if (!fRevertToInv) {                bool fFoundStartingHeader = false;                // Try to find first header that our peer doesn't have, and                // then send all headers past that one.  If we come across any                // headers that aren't on ::ChainActive(), give up.                for (const uint256 &hash : pto->vBlockHashesToAnnounce) {                    const CBlockIndex* pindex = LookupBlockIndex(hash);                    assert(pindex);                    if (::ChainActive()[pindex->nHeight] != pindex) {                        // Bail out if we reorged away from this block                        fRevertToInv = true;                        break;                    }                    if (pBestIndex != nullptr && pindex->pprev != pBestIndex) {                        // This means that the list of blocks to announce don't                        // connect to each other.                        // This shouldn't really be possible to hit during                        // regular operation (because reorgs should take us to                        // a chain that has some block not on the prior chain,                        // which should be caught by the prior check), but one                        // way this could happen is by using invalidateblock /                        // reconsiderblock repeatedly on the tip, causing it to                        // be added multiple times to vBlockHashesToAnnounce.                        // Robustly deal with this rare situation by reverting                        // to an inv.                        fRevertToInv = true;                        break;                    }                    pBestIndex = pindex;                    if (fFoundStartingHeader) {                        // add this to the headers message                        vHeaders.push_back(pindex->GetBlockHeader());                    } else if (PeerHasHeader(&state, pindex)) {                        continue; // keep looking for the first new block                    } else if (pindex->pprev == nullptr || PeerHasHeader(&state, pindex->pprev)) {                        // Peer doesn't have this header but they do have the prior one.                        // Start sending headers.                        fFoundStartingHeader = true;                        vHeaders.push_back(pindex->GetBlockHeader());                    } else {                        // Peer doesn't have this header or the prior one -- nothing will                        // connect, so bail out.                        fRevertToInv = true;                        break;                    }                }            }            if (!fRevertToInv && !vHeaders.empty()) {                if (vHeaders.size() == 1 && state.fPreferHeaderAndIDs) {                    // We only send up to 1 block as header-and-ids, as otherwise                    // probably means we're doing an initial-ish-sync or they're slow                    LogPrint(BCLog::NET, "%s sending header-and-ids %s to peer=%d\n", __func__,                            vHeaders.front().GetHash().ToString(), pto->GetId());                    int nSendFlags = state.fWantsCmpctWitness ? 0 : SERIALIZE_TRANSACTION_NO_WITNESS;                    nSendFlags |= state.fWantsCmpctMWEB ? 0 : SERIALIZE_NO_MWEB;                    bool fGotBlockFromCache = false;                    {                        LOCK(cs_most_recent_block);                        if (most_recent_block_hash == pBestIndex->GetBlockHash()) {                            if (state.fWantsCmpctWitness || !fWitnessesPresentInMostRecentCompactBlock)                                m_connman.PushMessage(pto, msgMaker.Make(nSendFlags, NetMsgType::CMPCTBLOCK, *most_recent_compact_block));                            else {                                CBlockHeaderAndShortTxIDs cmpctblock(*most_recent_block, state.fWantsCmpctWitness);                                m_connman.PushMessage(pto, msgMaker.Make(nSendFlags, NetMsgType::CMPCTBLOCK, cmpctblock));                            }                            fGotBlockFromCache = true;                        }                    }                    if (!fGotBlockFromCache) {                        CBlock block;                        bool ret = ReadBlockFromDisk(block, pBestIndex, consensusParams);                        assert(ret);                        CBlockHeaderAndShortTxIDs cmpctblock(block, state.fWantsCmpctWitness);                        m_connman.PushMessage(pto, msgMaker.Make(nSendFlags, NetMsgType::CMPCTBLOCK, cmpctblock));                    }                    state.pindexBestHeaderSent = pBestIndex;                } else if (state.fPreferHeaders) {                    if (vHeaders.size() > 1) {                        LogPrint(BCLog::NET, "%s: %u headers, range (%s, %s), to peer=%d\n", __func__,                                vHeaders.size(),                                vHeaders.front().GetHash().ToString(),                                vHeaders.back().GetHash().ToString(), pto->GetId());                    } else {                        LogPrint(BCLog::NET, "%s: sending header %s to peer=%d\n", __func__,                                vHeaders.front().GetHash().ToString(), pto->GetId());                    }                    m_connman.PushMessage(pto, msgMaker.Make(NetMsgType::HEADERS, vHeaders));                    state.pindexBestHeaderSent = pBestIndex;                } else                    fRevertToInv = true;            }            if (fRevertToInv) {                // If falling back to using an inv, just try to inv the tip.                // The last entry in vBlockHashesToAnnounce was our tip at some point                // in the past.                if (!pto->vBlockHashesToAnnounce.empty()) {                    const uint256 &hashToAnnounce = pto->vBlockHashesToAnnounce.back();                    const CBlockIndex* pindex = LookupBlockIndex(hashToAnnounce);                    assert(pindex);                    // Warn if we're announcing a block that is not on the main chain.                    // This should be very rare and could be optimized out.                    // Just log for now.                    if (::ChainActive()[pindex->nHeight] != pindex) {                        LogPrint(BCLog::NET, "Announcing block %s not on main chain (tip=%s)\n",                            hashToAnnounce.ToString(), ::ChainActive().Tip()->GetBlockHash().ToString());                    }                    // If the peer's chain has this block, don't inv it back.                    if (!PeerHasHeader(&state, pindex)) {                        pto->vInventoryBlockToSend.push_back(hashToAnnounce);                        LogPrint(BCLog::NET, "%s: sending inv peer=%d hash=%s\n", __func__,                            pto->GetId(), hashToAnnounce.ToString());                    }                }            }            pto->vBlockHashesToAnnounce.clear();        }        //        // Message: inventory        //        std::vector<CInv> vInv;        {            LOCK(pto->cs_inventory);            vInv.reserve(std::max<size_t>(pto->vInventoryBlockToSend.size(), INVENTORY_BROADCAST_MAX));            // Add blocks            for (const uint256& hash : pto->vInventoryBlockToSend) {                vInv.push_back(CInv(MSG_BLOCK, hash));                if (vInv.size() == MAX_INV_SZ) {                    m_connman.PushMessage(pto, msgMaker.Make(NetMsgType::INV, vInv));                    vInv.clear();                }            }            pto->vInventoryBlockToSend.clear();            if (pto->m_tx_relay != nullptr) {                LOCK(pto->m_tx_relay->cs_tx_inventory);                // Check whether periodic sends should happen                bool fSendTrickle = pto->HasPermission(PF_NOBAN);                if (pto->m_tx_relay->nNextInvSend < current_time) {                    fSendTrickle = true;                    if (pto->IsInboundConn()) {                        pto->m_tx_relay->nNextInvSend = std::chrono::microseconds{m_connman.PoissonNextSendInbound(count_microseconds(current_time), INVENTORY_BROADCAST_INTERVAL)};                    } else {                        // Use half the delay for outbound peers, as there is less privacy concern for them.                        pto->m_tx_relay->nNextInvSend = PoissonNextSend(current_time, std::chrono::seconds{INVENTORY_BROADCAST_INTERVAL >> 1});                    }                }                // Time to send but the peer has requested we not relay transactions.                if (fSendTrickle) {                    LOCK(pto->m_tx_relay->cs_filter);                    if (!pto->m_tx_relay->fRelayTxes) pto->m_tx_relay->setInventoryTxToSend.clear();                }                // Respond to BIP35 mempool requests                if (fSendTrickle && pto->m_tx_relay->fSendMempool) {                    auto vtxinfo = m_mempool.infoAll();                    pto->m_tx_relay->fSendMempool = false;                    CFeeRate filterrate;                    {                        LOCK(pto->m_tx_relay->cs_feeFilter);                        filterrate = CFeeRate(pto->m_tx_relay->minFeeFilter);                    }                    LOCK(pto->m_tx_relay->cs_filter);                    for (const auto& txinfo : vtxinfo) {                        const uint256& hash = state.m_wtxid_relay ? txinfo.tx->GetWitnessHash() : txinfo.tx->GetHash();                        CInv inv(state.m_wtxid_relay ? MSG_WTX : MSG_TX, hash);                        pto->m_tx_relay->setInventoryTxToSend.erase(hash);                        // Don't send transactions that peers will not put into their mempool                        if (txinfo.fee < filterrate.GetTotalFee(txinfo.vsize, txinfo.mweb_weight)) {                            continue;                        }                        if (pto->m_tx_relay->pfilter) {                            if (!pto->m_tx_relay->pfilter->IsRelevantAndUpdate(*txinfo.tx)) continue;                        }                        pto->m_tx_relay->filterInventoryKnown.insert(hash);                        // Responses to MEMPOOL requests bypass the m_recently_announced_invs filter.                        vInv.push_back(inv);                        if (vInv.size() == MAX_INV_SZ) {                            m_connman.PushMessage(pto, msgMaker.Make(NetMsgType::INV, vInv));                            vInv.clear();                        }                    }                    pto->m_tx_relay->m_last_mempool_req = GetTime<std::chrono::seconds>();                }                // Determine transactions to relay                if (fSendTrickle) {                    // Produce a vector with all candidates for sending                    std::vector<std::set<uint256>::iterator> vInvTx;                    vInvTx.reserve(pto->m_tx_relay->setInventoryTxToSend.size());                    for (std::set<uint256>::iterator it = pto->m_tx_relay->setInventoryTxToSend.begin(); it != pto->m_tx_relay->setInventoryTxToSend.end(); it++) {                        vInvTx.push_back(it);                    }                    CFeeRate filterrate;                    {                        LOCK(pto->m_tx_relay->cs_feeFilter);                        filterrate = CFeeRate(pto->m_tx_relay->minFeeFilter);                    }                    // Topologically and fee-rate sort the inventory we send for privacy and priority reasons.                    // A heap is used so that not all items need sorting if only a few are being sent.                    CompareInvMempoolOrder compareInvMempoolOrder(&m_mempool, state.m_wtxid_relay);                    std::make_heap(vInvTx.begin(), vInvTx.end(), compareInvMempoolOrder);                    // No reason to drain out at many times the network's capacity,                    // especially since we have many peers and some will draw much shorter delays.                    unsigned int nRelayedTransactions = 0;                    LOCK(pto->m_tx_relay->cs_filter);                    size_t broadcast_max{INVENTORY_BROADCAST_MAX + (pto->m_tx_relay->setInventoryTxToSend.size()/1000)*5};                    broadcast_max = std::min<size_t>(1000, broadcast_max);                    while (!vInvTx.empty() && nRelayedTransactions < broadcast_max) {                        // Fetch the top element from the heap                        std::pop_heap(vInvTx.begin(), vInvTx.end(), compareInvMempoolOrder);                        std::set<uint256>::iterator it = vInvTx.back();                        vInvTx.pop_back();                        uint256 hash = *it;                        CInv inv(state.m_wtxid_relay ? MSG_WTX : MSG_TX, hash);                        // Remove it from the to-be-sent set                        pto->m_tx_relay->setInventoryTxToSend.erase(it);                        // Check if not in the filter already                        if (pto->m_tx_relay->filterInventoryKnown.contains(hash)) {                            continue;                        }                        // Not in the mempool anymore? don't bother sending it.                        auto txinfo = m_mempool.info(ToGenTxid(inv));                        if (!txinfo.tx) {                            continue;                        }                        auto txid = txinfo.tx->GetHash();                        auto wtxid = txinfo.tx->GetWitnessHash();                        // Peer told you to not send transactions at that feerate? Don't bother sending it.                        if (txinfo.fee < filterrate.GetTotalFee(txinfo.vsize, txinfo.mweb_weight)) {                            continue;                        }                        if (pto->m_tx_relay->pfilter && !pto->m_tx_relay->pfilter->IsRelevantAndUpdate(*txinfo.tx)) continue;                        // Send                        State(pto->GetId())->m_recently_announced_invs.insert(hash);                        vInv.push_back(inv);                        nRelayedTransactions++;                        {                            // Expire old relay messages                            while (!vRelayExpiration.empty() && vRelayExpiration.front().first < count_microseconds(current_time))                            {                                mapRelay.erase(vRelayExpiration.front().second);                                vRelayExpiration.pop_front();                            }                            auto ret = mapRelay.emplace(txid, std::move(txinfo.tx));                            if (ret.second) {                                vRelayExpiration.emplace_back(count_microseconds(current_time + std::chrono::microseconds{RELAY_TX_CACHE_TIME}), ret.first);                            }                            // Add wtxid-based lookup into mapRelay as well, so that peers can request by wtxid                            auto ret2 = mapRelay.emplace(wtxid, ret.first->second);                            if (ret2.second) {                                vRelayExpiration.emplace_back(count_microseconds(current_time + std::chrono::microseconds{RELAY_TX_CACHE_TIME}), ret2.first);                            }                        }                        if (vInv.size() == MAX_INV_SZ) {                            m_connman.PushMessage(pto, msgMaker.Make(NetMsgType::INV, vInv));                            vInv.clear();                        }                        pto->m_tx_relay->filterInventoryKnown.insert(hash);                        if (hash != txid) {                            // Insert txid into filterInventoryKnown, even for                            // wtxidrelay peers. This prevents re-adding of                            // unconfirmed parents to the recently_announced                            // filter, when a child tx is requested. See                            // ProcessGetData().                            pto->m_tx_relay->filterInventoryKnown.insert(txid);                        }                    }                }            }        }        if (!vInv.empty())            m_connman.PushMessage(pto, msgMaker.Make(NetMsgType::INV, vInv));        // Detect whether we're stalling        current_time = GetTime<std::chrono::microseconds>();        if (state.nStallingSince && state.nStallingSince < count_microseconds(current_time) - 1000000 * BLOCK_STALLING_TIMEOUT) {            // Stalling only triggers when the block download window cannot move. During normal steady state,            // the download window should be much larger than the to-be-downloaded set of blocks, so disconnection            // should only happen during initial block download.            LogPrintf("Peer=%d is stalling block download, disconnecting\n", pto->GetId());            pto->fDisconnect = true;            return true;        }        // In case there is a block that has been in flight from this peer for 2 + 0.5 * N times the block interval        // (with N the number of peers from which we're downloading validated blocks), disconnect due to timeout.        // We compensate for other peers to prevent killing off peers due to our own downstream link        // being saturated. We only count validated in-flight blocks so peers can't advertise non-existing block hashes        // to unreasonably increase our timeout.        if (state.vBlocksInFlight.size() > 0) {            QueuedBlock &queuedBlock = state.vBlocksInFlight.front();            int nOtherPeersWithValidatedDownloads = nPeersWithValidatedDownloads - (state.nBlocksInFlightValidHeaders > 0);            if (count_microseconds(current_time) > state.nDownloadingSince + consensusParams.nPowTargetSpacing * (BLOCK_DOWNLOAD_TIMEOUT_BASE + BLOCK_DOWNLOAD_TIMEOUT_PER_PEER * nOtherPeersWithValidatedDownloads)) {                LogPrintf("Timeout downloading block %s from peer=%d, disconnecting\n", queuedBlock.hash.ToString(), pto->GetId());                pto->fDisconnect = true;                return true;            }        }        // Check for headers sync timeouts        if (state.fSyncStarted && state.nHeadersSyncTimeout < std::numeric_limits<int64_t>::max()) {            // Detect whether this is a stalling initial-headers-sync peer            if (pindexBestHeader->GetBlockTime() <= GetAdjustedTime() - 24 * 60 * 60) {                if (count_microseconds(current_time) > state.nHeadersSyncTimeout && nSyncStarted == 1 && (nPreferredDownload - state.fPreferredDownload >= 1)) {                    // Disconnect a peer (without the noban permission) if it is our only sync peer,                    // and we have others we could be using instead.                    // Note: If all our peers are inbound, then we won't                    // disconnect our sync peer for stalling; we have bigger                    // problems if we can't get any outbound peers.                    if (!pto->HasPermission(PF_NOBAN)) {                        LogPrintf("Timeout downloading headers from peer=%d, disconnecting\n", pto->GetId());                        pto->fDisconnect = true;                        return true;                    } else {                        LogPrintf("Timeout downloading headers from noban peer=%d, not disconnecting\n", pto->GetId());                        // Reset the headers sync state so that we have a                        // chance to try downloading from a different peer.                        // Note: this will also result in at least one more                        // getheaders message to be sent to                        // this peer (eventually).                        state.fSyncStarted = false;                        nSyncStarted--;                        state.nHeadersSyncTimeout = 0;                    }                }            } else {                // After we've caught up once, reset the timeout so we can't trigger                // disconnect later.                state.nHeadersSyncTimeout = std::numeric_limits<int64_t>::max();            }        }        // Check that outbound peers have reasonable chains        // GetTime() is used by this anti-DoS logic so we can test this using mocktime        ConsiderEviction(*pto, GetTime());        //        // Message: getdata (blocks)        //        std::vector<CInv> vGetData;        if (!pto->fClient && ((fFetch && !pto->m_limited_node) || !::ChainstateActive().IsInitialBlockDownload()) && state.nBlocksInFlight < MAX_BLOCKS_IN_TRANSIT_PER_PEER) {            std::vector<const CBlockIndex*> vToDownload;            NodeId staller = -1;            FindNextBlocksToDownload(pto->GetId(), MAX_BLOCKS_IN_TRANSIT_PER_PEER - state.nBlocksInFlight, vToDownload, staller, consensusParams);            for (const CBlockIndex *pindex : vToDownload) {                uint32_t nFetchFlags = GetFetchFlags(*pto);                vGetData.push_back(CInv(MSG_BLOCK | nFetchFlags, pindex->GetBlockHash()));                MarkBlockAsInFlight(m_mempool, pto->GetId(), pindex->GetBlockHash(), pindex);                LogPrint(BCLog::NET, "Requesting block %s (%d) peer=%d\n", pindex->GetBlockHash().ToString(),                    pindex->nHeight, pto->GetId());            }            if (state.nBlocksInFlight == 0 && staller != -1) {                if (State(staller)->nStallingSince == 0) {                    State(staller)->nStallingSince = count_microseconds(current_time);                    LogPrint(BCLog::NET, "Stall started peer=%d\n", staller);                }            }        }        //        // Message: getdata (non-blocks)        //        std::vector<std::pair<NodeId, GenTxid>> expired;        auto requestable = m_txrequest.GetRequestable(pto->GetId(), current_time, &expired);        for (const auto& entry : expired) {            LogPrint(BCLog::NET, "timeout of inflight %s %s from peer=%d\n", entry.second.IsWtxid() ? "wtx" : "tx",                entry.second.GetHash().ToString(), entry.first);        }        for (const GenTxid& gtxid : requestable) {            if (!AlreadyHaveTx(gtxid, m_mempool)) {                LogPrint(BCLog::NET, "Requesting %s %s peer=%d\n", gtxid.IsWtxid() ? "wtx" : "tx",                    gtxid.GetHash().ToString(), pto->GetId());                vGetData.emplace_back(gtxid.IsWtxid() ? MSG_WTX : (MSG_TX | GetFetchFlags(*pto)), gtxid.GetHash());                if (vGetData.size() >= MAX_GETDATA_SZ) {                    m_connman.PushMessage(pto, msgMaker.Make(NetMsgType::GETDATA, vGetData));                    vGetData.clear();                }                m_txrequest.RequestedTx(pto->GetId(), gtxid.GetHash(), current_time + GETDATA_TX_INTERVAL);            } else {                // We have already seen this transaction, no need to download. This is just a belt-and-suspenders, as                // this should already be called whenever a transaction becomes AlreadyHaveTx().                m_txrequest.ForgetTxHash(gtxid.GetHash());            }        }        if (!vGetData.empty())            m_connman.PushMessage(pto, msgMaker.Make(NetMsgType::GETDATA, vGetData));        //        // Message: feefilter        //        if (pto->m_tx_relay != nullptr && pto->GetCommonVersion() >= FEEFILTER_VERSION && gArgs.GetBoolArg("-feefilter", DEFAULT_FEEFILTER) &&            !pto->HasPermission(PF_FORCERELAY) // peers with the forcerelay permission should not filter txs to us        ) {            CAmount currentFilter = m_mempool.GetMinFee(gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000).GetFeePerK();            static FeeFilterRounder g_filter_rounder{CFeeRate{DEFAULT_MIN_RELAY_TX_FEE}};            if (m_chainman.ActiveChainstate().IsInitialBlockDownload()) {                // Received tx-inv messages are discarded when the active                // chainstate is in IBD, so tell the peer to not send them.                currentFilter = MAX_MONEY;            } else {                static const CAmount MAX_FILTER{g_filter_rounder.round(MAX_MONEY)};                if (pto->m_tx_relay->lastSentFeeFilter == MAX_FILTER) {                    // Send the current filter if we sent MAX_FILTER previously                    // and made it out of IBD.                    pto->m_tx_relay->nextSendTimeFeeFilter = count_microseconds(current_time) - 1;                }            }            if (count_microseconds(current_time) > pto->m_tx_relay->nextSendTimeFeeFilter) {                CAmount filterToSend = g_filter_rounder.round(currentFilter);                // We always have a fee filter of at least minRelayTxFee                filterToSend = std::max(filterToSend, ::minRelayTxFee.GetFeePerK());                if (filterToSend != pto->m_tx_relay->lastSentFeeFilter) {                    m_connman.PushMessage(pto, msgMaker.Make(NetMsgType::FEEFILTER, filterToSend));                    pto->m_tx_relay->lastSentFeeFilter = filterToSend;                }                pto->m_tx_relay->nextSendTimeFeeFilter = PoissonNextSend(count_microseconds(current_time), AVG_FEEFILTER_BROADCAST_INTERVAL);            }            // If the fee filter has changed substantially and it's still more than MAX_FEEFILTER_CHANGE_DELAY            // until scheduled broadcast, then move the broadcast to within MAX_FEEFILTER_CHANGE_DELAY.            else if (count_microseconds(current_time) + MAX_FEEFILTER_CHANGE_DELAY * 1000000 < pto->m_tx_relay->nextSendTimeFeeFilter &&                     (currentFilter < 3 * pto->m_tx_relay->lastSentFeeFilter / 4 || currentFilter > 4 * pto->m_tx_relay->lastSentFeeFilter / 3)) {                pto->m_tx_relay->nextSendTimeFeeFilter = count_microseconds(current_time) + GetRandInt(MAX_FEEFILTER_CHANGE_DELAY) * 1000000;            }        }    } // release cs_main    return true;}class CNetProcessingCleanup{public:    CNetProcessingCleanup() {}    ~CNetProcessingCleanup() {        // orphan transactions        mapOrphanTransactions.clear();        mapOrphanTransactionsByPrev.clear();        g_orphans_by_wtxid.clear();    }};static CNetProcessingCleanup instance_of_cnetprocessingcleanup;