diff --git a/src/net_processing.cpp b/src/net_processing.cpp index dbd55e30a1..569dc76269 100644 --- a/src/net_processing.cpp +++ b/src/net_processing.cpp @@ -1,4263 +1,4279 @@ // Copyright (c) 2009-2010 Satoshi Nakamoto // Copyright (c) 2009-2016 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 "arith_uint256.h" #include "blockencodings.h" #include "blockvalidity.h" #include "chainparams.h" #include "config.h" #include "consensus/validation.h" #include "hash.h" #include "init.h" #include "merkleblock.h" #include "net.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 "tinyformat.h" #include "txmempool.h" #include "ui_interface.h" #include "util.h" #include "utilmoneystr.h" #include "utilstrencodings.h" #include "validation.h" #include "validationinterface.h" #if defined(NDEBUG) #error "Bitcoin cannot be compiled without assertions." #endif // Used only to inform the wallet of when we last received a block. std::atomic nTimeBestReceived(0); struct IteratorComparator { template bool operator()(const I &a, const I &b) { return &(*a) < &(*b); } }; struct COrphanTx { // When modifying, adapt the copy of this definition in tests/DoS_tests. CTransactionRef tx; NodeId fromPeer; int64_t nTimeExpire; }; std::map mapOrphanTransactions GUARDED_BY(cs_main); std::map::iterator, IteratorComparator>> mapOrphanTransactionsByPrev GUARDED_BY(cs_main); void EraseOrphansFor(NodeId peer) EXCLUSIVE_LOCKS_REQUIRED(cs_main); static size_t vExtraTxnForCompactIt = 0; static std::vector> vExtraTxnForCompact GUARDED_BY(cs_main); // SHA256("main address relay")[0:8] static const 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 const 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 const int HISTORICAL_BLOCK_AGE = 7 * 24 * 60 * 60; + // Internal stuff namespace { /** Number of nodes with fSyncStarted. */ int nSyncStarted GUARDED_BY(cs_main) = 0; /** * Sources of received blocks, saved to be able to send them reject messages or * ban 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> 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. * * Memory used: 1.3 MB */ std::unique_ptr recentRejects GUARDED_BY(cs_main); uint256 hashRecentRejectsChainTip GUARDED_BY(cs_main); /** * Blocks that are in flight, and that are in the queue to be downloaded. */ struct QueuedBlock { uint256 hash; //!< Optional. const CBlockIndex *pindex; //!< Whether this block has validated headers at the time of request. bool fValidatedHeaders; //!< Optional, used for CMPCTBLOCK downloads std::unique_ptr partialBlock; }; std::map::iterator>> mapBlocksInFlight GUARDED_BY(cs_main); /** Stack of nodes which we have set to announce using compact blocks */ std::list lNodesAnnouncingHeaderAndIDs; /** 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 outbound peers with m_chain_sync.m_protect. */ int g_outbound_peers_with_protect_from_disconnect = 0; /** When our tip was last updated. */ int64_t g_last_tip_update = 0; /** Relay map. */ typedef std::map MapRelay; MapRelay mapRelay GUARDED_BY(cs_main); /** * Expiration-time ordered list of (expire time, relay map entry) pairs, * protected by cs_main). */ std::deque> vRelayExpiration GUARDED_BY(cs_main); } // namespace namespace { struct CBlockReject { uint8_t chRejectCode; std::string strRejectReason; uint256 hashBlock; }; /** * 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; //! Accumulated misbehaviour score for this peer. int nMisbehavior; //! Whether this peer should be disconnected and banned (unless //! whitelisted). bool fShouldBan; //! String name of this peer (debugging/logging purposes). const std::string name; //! List of asynchronously-determined block rejections to notify this peer //! about. std::vector rejects; //! 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 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 we send. */ bool fProvidesHeaderAndIDs; /** * 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; /** * State used to enforce CHAIN_SYNC_TIMEOUT * Only in effect for outbound, non-manual connections, * with m_protect == false * Algorithm: 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. */ 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; CNodeState(CAddress addrIn, std::string addrNameIn) : address(addrIn), name(addrNameIn) { fCurrentlyConnected = false; nMisbehavior = 0; fShouldBan = 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; fSupportsDesiredCmpctVersion = false; m_chain_sync = {0, nullptr, false, false}; m_last_block_announcement = 0; } }; /** Map maintaining per-node state. */ static std::map mapNodeState GUARDED_BY(cs_main); static CNodeState *State(NodeId pnode) EXCLUSIVE_LOCKS_REQUIRED(cs_main) { std::map::iterator it = mapNodeState.find(pnode); if (it == mapNodeState.end()) { return nullptr; } return &it->second; } static void UpdatePreferredDownload(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->fInbound || node->fWhitelisted) && !node->fOneShot && !node->fClient; nPreferredDownload += state->fPreferredDownload; } static void PushNodeVersion(const Config &config, CNode *pnode, CConnman *connman, int64_t nTime) { 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 : 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, userAgent(config), nNodeStartingHeight, ::fRelayTxes)); 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 // peer. static bool MarkBlockAsReceived(const uint256 &hash) EXCLUSIVE_LOCKS_REQUIRED(cs_main) { std::map::iterator>>::iterator itInFlight = mapBlocksInFlight.find(hash); if (itInFlight != mapBlocksInFlight.end()) { CNodeState *state = State(itInFlight->second.first); 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, GetTimeMicros()); } 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 held. static bool MarkBlockAsInFlight(const Config &config, NodeId nodeid, const uint256 &hash, const Consensus::Params &consensusParams, const CBlockIndex *pindex = nullptr, std::list::iterator **pit = nullptr) EXCLUSIVE_LOCKS_REQUIRED(cs_main) { CNodeState *state = State(nodeid); assert(state != nullptr); // Short-circuit most stuff in case its from the same node. std::map::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); std::list::iterator it = state->vBlocksInFlight.insert( state->vBlocksInFlight.end(), {hash, pindex, pindex != nullptr, std::unique_ptr( pit ? new PartiallyDownloadedBlock(config, &g_mempool) : nullptr)}); state->nBlocksInFlight++; state->nBlocksInFlightValidHeaders += it->fValidatedHeaders; if (state->nBlocksInFlight == 1) { // We're starting a block download (batch) from this peer. state->nDownloadingSince = GetTimeMicros(); } 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()) { BlockMap::iterator itOld = mapBlockIndex.find(state->hashLastUnknownBlock); if (itOld != mapBlockIndex.end() && itOld->second->nChainWork > 0) { if (state->pindexBestKnownBlock == nullptr || itOld->second->nChainWork >= state->pindexBestKnownBlock->nChainWork) { state->pindexBestKnownBlock = itOld->second; } 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); BlockMap::iterator it = mapBlockIndex.find(hash); if (it != mapBlockIndex.end() && it->second->nChainWork > 0) { // An actually better block was announced. if (state->pindexBestKnownBlock == nullptr || it->second->nChainWork >= state->pindexBestKnownBlock->nChainWork) { state->pindexBestKnownBlock = it->second; } } 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) { AssertLockHeld(cs_main); CNodeState *nodestate = State(nodeid); if (!nodestate) { LogPrint(BCLog::NET, "node state unavailable: peer=%d\n", nodeid); return; } if (!nodestate->fProvidesHeaderAndIDs) { return; } for (std::list::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) { AssertLockHeld(cs_main); bool fAnnounceUsingCMPCTBLOCK = false; uint64_t nCMPCTBLOCKVersion = 1; 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, fAnnounceUsingCMPCTBLOCK, nCMPCTBLOCKVersion](CNode *pnodeStop) { AssertLockHeld(cs_main); connman->PushMessage( pnodeStop, CNetMsgMaker(pnodeStop->GetSendVersion()) .Make(NetMsgType::SENDCMPCT, fAnnounceUsingCMPCTBLOCK, nCMPCTBLOCKVersion)); return true; }); lNodesAnnouncingHeaderAndIDs.pop_front(); } fAnnounceUsingCMPCTBLOCK = true; connman->PushMessage(pfrom, CNetMsgMaker(pfrom->GetSendVersion()) .Make(NetMsgType::SENDCMPCT, fAnnounceUsingCMPCTBLOCK, 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 &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 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(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(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 mean time, 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(BlockValidity::TREE)) { // We consider the chain that this peer is on invalid. return; } if (pindex->nStatus.hasData() || chainActive.Contains(pindex)) { if (pindex->nChainTx) { 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; } } } } } // namespace // This function is used for testing the stale tip eviction logic, see // DoS_tests.cpp void 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; } } // Returns true for outbound peers, excluding manual connections, feelers, and // one-shots. static bool IsOutboundDisconnectionCandidate(const CNode *node) { return !(node->fInbound || node->m_manual_connection || node->fFeeler || node->fOneShot); } void PeerLogicValidation::InitializeNode(const Config &config, 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, std::move(addrName))); } if (!pnode->fInbound) { PushNodeVersion(config, pnode, connman, GetTime()); } } void PeerLogicValidation::FinalizeNode(const Config &config, NodeId nodeid, bool &fUpdateConnectionTime) { fUpdateConnectionTime = false; LOCK(cs_main); CNodeState *state = State(nodeid); assert(state != nullptr); if (state->fSyncStarted) { nSyncStarted--; } if (state->nMisbehavior == 0 && state->fCurrentlyConnected) { fUpdateConnectionTime = true; } for (const QueuedBlock &entry : state->vBlocksInFlight) { mapBlocksInFlight.erase(entry.hash); } EraseOrphansFor(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); 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); } 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.nMisbehavior = state->nMisbehavior; 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); } } return true; } ////////////////////////////////////////////////////////////////////////////// // // mapOrphanTransactions // static void AddToCompactExtraTransactions(const CTransactionRef &tx) EXCLUSIVE_LOCKS_REQUIRED(cs_main) { 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->GetId(), tx); vExtraTxnForCompactIt = (vExtraTxnForCompactIt + 1) % max_extra_txn; } bool AddOrphanTx(const CTransactionRef &tx, NodeId peer) EXCLUSIVE_LOCKS_REQUIRED(cs_main) { const uint256 &txid = tx->GetId(); if (mapOrphanTransactions.count(txid)) { 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 99,999 bytes big is at most 10 // megabytes of orphans and somewhat more byprev index (in the worst case): unsigned int sz = tx->GetTotalSize(); if (sz >= MAX_STANDARD_TX_SIZE) { LogPrint(BCLog::MEMPOOL, "ignoring large orphan tx (size: %u, hash: %s)\n", sz, txid.ToString()); return false; } auto ret = mapOrphanTransactions.emplace( txid, COrphanTx{tx, peer, GetTime() + ORPHAN_TX_EXPIRE_TIME}); assert(ret.second); 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", txid.ToString(), mapOrphanTransactions.size(), mapOrphanTransactionsByPrev.size()); return true; } static int EraseOrphanTx(uint256 hash) EXCLUSIVE_LOCKS_REQUIRED(cs_main) { std::map::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); } } mapOrphanTransactions.erase(it); return 1; } void EraseOrphansFor(NodeId peer) { int nErased = 0; std::map::iterator iter = mapOrphanTransactions.begin(); while (iter != mapOrphanTransactions.end()) { // Increment to avoid iterator becoming invalid. std::map::iterator maybeErase = iter++; if (maybeErase->second.fromPeer == peer) { nErased += EraseOrphanTx(maybeErase->second.tx->GetId()); } } if (nErased > 0) { LogPrint(BCLog::MEMPOOL, "Erased %d orphan tx from peer=%d\n", nErased, peer); } } unsigned int LimitOrphanTxSize(unsigned int nMaxOrphans) EXCLUSIVE_LOCKS_REQUIRED(cs_main) { 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::iterator iter = mapOrphanTransactions.begin(); while (iter != mapOrphanTransactions.end()) { std::map::iterator maybeErase = iter++; if (maybeErase->second.nTimeExpire <= nNow) { nErased += EraseOrphanTx(maybeErase->second.tx->GetId()); } 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); } } while (mapOrphanTransactions.size() > nMaxOrphans) { // Evict a random orphan: uint256 randomhash = GetRandHash(); std::map::iterator it = mapOrphanTransactions.lower_bound(randomhash); if (it == mapOrphanTransactions.end()) { it = mapOrphanTransactions.begin(); } EraseOrphanTx(it->first); ++nEvicted; } return nEvicted; } /** * Mark a misbehaving peer to be banned depending upon the value of `-banscore`. */ void Misbehaving(NodeId pnode, int howmuch, const std::string &reason) EXCLUSIVE_LOCKS_REQUIRED(cs_main) { if (howmuch == 0) { return; } CNodeState *state = State(pnode); if (state == nullptr) { return; } state->nMisbehavior += howmuch; int banscore = gArgs.GetArg("-banscore", DEFAULT_BANSCORE_THRESHOLD); if (state->nMisbehavior >= banscore && state->nMisbehavior - howmuch < banscore) { LogPrintf( "%s: %s peer=%d (%d -> %d) reason: %s BAN THRESHOLD EXCEEDED\n", __func__, state->name, pnode, state->nMisbehavior - howmuch, state->nMisbehavior, reason.c_str()); state->fShouldBan = true; } else { LogPrintf("%s: %s peer=%d (%d -> %d) reason: %s\n", __func__, state->name, pnode, state->nMisbehavior - howmuch, state->nMisbehavior, reason.c_str()); } } // overloaded variant of above to operate on CNode*s static void Misbehaving(CNode *node, int howmuch, const std::string &reason) EXCLUSIVE_LOCKS_REQUIRED(cs_main) { Misbehaving(node->GetId(), howmuch, reason); } ////////////////////////////////////////////////////////////////////////////// // // 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. +static bool StaleBlockRequestAllowed(const CBlockIndex *pindex, + const Consensus::Params &consensusParams) { + AssertLockHeld(cs_main); + return (pindexBestHeader != nullptr) && + (pindexBestHeader->GetBlockTime() - pindex->GetBlockTime() < + STALE_RELAY_AGE_LIMIT) && + (GetBlockProofEquivalentTime(*pindexBestHeader, *pindex, + *pindexBestHeader, consensusParams) < + STALE_RELAY_AGE_LIMIT); +} + PeerLogicValidation::PeerLogicValidation(CConnman *connmanIn, CScheduler &scheduler) : connman(connmanIn), m_stale_tip_check_time(0) { // Initialize global variables that cannot be constructed at startup. recentRejects.reset(new CRollingBloomFilter(120000, 0.000001)); const Consensus::Params &consensusParams = Params().GetConsensus(); // 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, &consensusParams]() { this->CheckForStaleTipAndEvictPeers(consensusParams); return true; }, EXTRA_PEER_CHECK_INTERVAL * 1000); } void PeerLogicValidation::BlockConnected( const std::shared_ptr &pblock, const CBlockIndex *pindex, const std::vector &vtxConflicted) { LOCK(cs_main); std::vector vOrphanErase; for (const CTransactionRef &ptx : pblock->vtx) { const CTransaction &tx = *ptx; // Which orphan pool entries must we evict? for (size_t j = 0; j < tx.vin.size(); j++) { auto itByPrev = mapOrphanTransactionsByPrev.find(tx.vin[j].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 include or precluded by this block if (vOrphanErase.size()) { int nErased = 0; for (uint256 &orphanId : vOrphanErase) { nErased += EraseOrphanTx(orphanId); } LogPrint(BCLog::MEMPOOL, "Erased %d orphan tx included or conflicted by block\n", nErased); } g_last_tip_update = GetTime(); } static CCriticalSection cs_most_recent_block; static std::shared_ptr most_recent_block GUARDED_BY(cs_most_recent_block); static std::shared_ptr most_recent_compact_block GUARDED_BY(cs_most_recent_block); static uint256 most_recent_block_hash GUARDED_BY(cs_most_recent_block); void PeerLogicValidation::NewPoWValidBlock( const CBlockIndex *pindex, const std::shared_ptr &pblock) { std::shared_ptr pcmpctblock = std::make_shared(*pblock); const CNetMsgMaker msgMaker(PROTOCOL_VERSION); LOCK(cs_main); static int nHighestFastAnnounce = 0; if (pindex->nHeight <= nHighestFastAnnounce) { return; } nHighestFastAnnounce = pindex->nHeight; uint256 hashBlock(pblock->GetHash()); { LOCK(cs_most_recent_block); most_recent_block_hash = hashBlock; most_recent_block = pblock; most_recent_compact_block = pcmpctblock; } connman->ForEachNode([this, &pcmpctblock, pindex, &msgMaker, &hashBlock](CNode *pnode) { AssertLockHeld(cs_main); // TODO: Avoid the repeated-serialization here if (pnode->nVersion < 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 && !PeerHasHeader(&state, pindex) && PeerHasHeader(&state, pindex->pprev)) { LogPrint(BCLog::NET, "%s sending header-and-ids %s to peer=%d\n", "PeerLogicValidation::NewPoWValidBlock", hashBlock.ToString(), pnode->GetId()); connman->PushMessage( pnode, msgMaker.Make(NetMsgType::CMPCTBLOCK, *pcmpctblock)); state.pindexBestHeaderSent = pindex; } }); } void PeerLogicValidation::UpdatedBlockTip(const CBlockIndex *pindexNew, const CBlockIndex *pindexFork, bool fInitialDownload) { const int nNewHeight = pindexNew->nHeight; connman->SetBestHeight(nNewHeight); if (!fInitialDownload) { // Find the hashes of all blocks that weren't previously in the best // chain. std::vector 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. connman->ForEachNode([nNewHeight, &vHashes](CNode *pnode) { if (nNewHeight > (pnode->nStartingHeight != -1 ? pnode->nStartingHeight - 2000 : 0)) { for (const uint256 &hash : reverse_iterate(vHashes)) { pnode->PushBlockHash(hash); } } }); connman->WakeMessageHandler(); } nTimeBestReceived = GetTime(); } void PeerLogicValidation::BlockChecked(const CBlock &block, const CValidationState &state) { LOCK(cs_main); const uint256 hash(block.GetHash()); std::map>::iterator it = mapBlockSource.find(hash); int nDoS = 0; if (state.IsInvalid(nDoS)) { // Don't send reject message with code 0 or an internal reject code. if (it != mapBlockSource.end() && State(it->second.first) && state.GetRejectCode() > 0 && state.GetRejectCode() < REJECT_INTERNAL) { CBlockReject reject = { uint8_t(state.GetRejectCode()), state.GetRejectReason().substr(0, MAX_REJECT_MESSAGE_LENGTH), hash}; State(it->second.first)->rejects.push_back(reject); if (nDoS > 0 && it->second.second) { Misbehaving(it->second.first, nDoS, state.GetRejectReason()); } } } // 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() && !IsInitialBlockDownload() && mapBlocksInFlight.count(hash) == mapBlocksInFlight.size()) { if (it != mapBlockSource.end()) { MaybeSetPeerAsAnnouncingHeaderAndIDs(it->second.first, connman); } } if (it != mapBlockSource.end()) { mapBlockSource.erase(it); } } ////////////////////////////////////////////////////////////////////////////// // // Messages // static bool AlreadyHave(const CInv &inv) EXCLUSIVE_LOCKS_REQUIRED(cs_main) { switch (inv.type) { case MSG_TX: { 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(); } // Use pcoinsTip->HaveCoinInCache as a quick approximation to // exclude requesting or processing some txs which have already been // included in a block. As this is best effort, we only check for // output 0 and 1. This works well enough in practice and we get // diminishing returns with 2 onward. return recentRejects->contains(inv.hash) || g_mempool.exists(inv.hash) || mapOrphanTransactions.count(inv.hash) || pcoinsTip->HaveCoinInCache(COutPoint(inv.hash, 0)) || pcoinsTip->HaveCoinInCache(COutPoint(inv.hash, 1)); } case MSG_BLOCK: return mapBlockIndex.count(inv.hash); } // Don't know what it is, just say we already got one return true; } static void RelayTransaction(const CTransaction &tx, CConnman *connman) { CInv inv(MSG_TX, tx.GetId()); connman->ForEachNode([&inv](CNode *pnode) { pnode->PushInventory(inv); }); } static void RelayAddress(const CAddress &addr, bool fReachable, CConnman *connman) { // Limited relaying of addresses outside our network(s) unsigned int nRelayNodes = fReachable ? 2 : 1; // 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 addrKnowns 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; std::array, 2> best{ {{0, nullptr}, {0, nullptr}}}; assert(nRelayNodes <= best.size()); auto sortfunc = [&best, &hasher, nRelayNodes](CNode *pnode) { if (pnode->nVersion >= CADDR_TIME_VERSION) { 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 ProcessGetData(const Config &config, CNode *pfrom, CConnman *connman, const std::atomic &interruptMsgProc) { const Consensus::Params &consensusParams = config.GetChainParams().GetConsensus(); std::deque::iterator it = pfrom->vRecvGetData.begin(); std::vector vNotFound; const CNetMsgMaker msgMaker(pfrom->GetSendVersion()); LOCK(cs_main); while (it != pfrom->vRecvGetData.end()) { // Don't bother if send buffer is too full to respond anyway. if (pfrom->fPauseSend) { break; } const CInv &inv = *it; { if (interruptMsgProc) { return; } it++; if (inv.type == MSG_BLOCK || inv.type == MSG_FILTERED_BLOCK || inv.type == MSG_CMPCT_BLOCK) { bool send = false; BlockMap::iterator mi = mapBlockIndex.find(inv.hash); if (mi != mapBlockIndex.end()) { if (mi->second->nChainTx && !mi->second->IsValid(BlockValidity::SCRIPTS) && mi->second->IsValid(BlockValidity::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. std::shared_ptr a_recent_block; { LOCK(cs_most_recent_block); a_recent_block = most_recent_block; } CValidationState dummy; ActivateBestChain(config, dummy, a_recent_block); } if (chainActive.Contains(mi->second)) { send = true; } else { - static const int nOneMonth = 30 * 24 * 60 * 60; - // To prevent fingerprinting attacks, only send blocks - // outside of the active chain if they are valid, and no - // more than a month older (both in time, and in best - // equivalent proof of work) than the best header chain - // we know about. send = mi->second->IsValid(BlockValidity::SCRIPTS) && - (pindexBestHeader != nullptr) && - (pindexBestHeader->GetBlockTime() - - mi->second->GetBlockTime() < - nOneMonth) && - (GetBlockProofEquivalentTime( - *pindexBestHeader, *mi->second, - *pindexBestHeader, - consensusParams) < nOneMonth); + StaleBlockRequestAllowed(mi->second, + consensusParams); if (!send) { LogPrintf("%s: ignoring request from peer=%i for " "old block that isn't in the main " "chain\n", __func__, pfrom->GetId()); } } } // Disconnect node in case we have reached the outbound limit - // for serving historical blocks never disconnect whitelisted - // nodes. - // assume > 1 week = historical - static const int nOneWeek = 7 * 24 * 60 * 60; + // for serving historical blocks. + // Never disconnect whitelisted nodes. if (send && connman->OutboundTargetReached(true) && (((pindexBestHeader != nullptr) && (pindexBestHeader->GetBlockTime() - mi->second->GetBlockTime() > - nOneWeek)) || + HISTORICAL_BLOCK_AGE)) || inv.type == MSG_FILTERED_BLOCK) && !pfrom->fWhitelisted) { LogPrint(BCLog::NET, "historical block serving limit " "reached, disconnect peer=%d\n", pfrom->GetId()); // disconnect node pfrom->fDisconnect = true; send = false; } // Pruned nodes may have deleted the block, so check whether // it's available before trying to send. if (send && (mi->second->nStatus.hasData())) { // Send block from disk CBlock block; if (!ReadBlockFromDisk(block, (*mi).second, config)) { assert(!"cannot load block from disk"); } if (inv.type == MSG_BLOCK) { connman->PushMessage( pfrom, msgMaker.Make(NetMsgType::BLOCK, block)); } else if (inv.type == MSG_FILTERED_BLOCK) { bool sendMerkleBlock = false; CMerkleBlock merkleBlock; { LOCK(pfrom->cs_filter); if (pfrom->pfilter) { sendMerkleBlock = true; merkleBlock = CMerkleBlock(block, *pfrom->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 PairType; for (PairType &pair : merkleBlock.vMatchedTxn) { connman->PushMessage( pfrom, msgMaker.Make(NetMsgType::TX, *block.vtx[pair.first])); } } // else // no response } else if (inv.type == MSG_CMPCT_BLOCK) { // 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. int nSendFlags = 0; if (CanDirectFetch(consensusParams) && mi->second->nHeight >= chainActive.Height() - MAX_CMPCTBLOCK_DEPTH) { CBlockHeaderAndShortTxIDs cmpctblock(block); connman->PushMessage( pfrom, msgMaker.Make(nSendFlags, NetMsgType::CMPCTBLOCK, cmpctblock)); } else { connman->PushMessage( pfrom, msgMaker.Make(nSendFlags, NetMsgType::BLOCK, block)); } } // Trigger the peer node to send a getblocks request for the // next batch of inventory. if (inv.hash == pfrom->hashContinue) { // Bypass PushInventory, 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 vInv; vInv.push_back( CInv(MSG_BLOCK, chainActive.Tip()->GetBlockHash())); connman->PushMessage( pfrom, msgMaker.Make(NetMsgType::INV, vInv)); pfrom->hashContinue.SetNull(); } } } else if (inv.type == MSG_TX) { // Send stream from relay memory bool push = false; auto mi = mapRelay.find(inv.hash); int nSendFlags = 0; if (mi != mapRelay.end()) { connman->PushMessage( pfrom, msgMaker.Make(nSendFlags, NetMsgType::TX, *mi->second)); push = true; } else if (pfrom->timeLastMempoolReq) { auto txinfo = g_mempool.info(inv.hash); // To protect privacy, do not answer getdata using the // mempool when that TX couldn't have been INVed in reply to // a MEMPOOL request. if (txinfo.tx && txinfo.nTime <= pfrom->timeLastMempoolReq) { connman->PushMessage(pfrom, msgMaker.Make(nSendFlags, NetMsgType::TX, *txinfo.tx)); push = true; } } if (!push) { vNotFound.push_back(inv); } } // Track requests for our stuff. GetMainSignals().Inventory(inv.hash); if (inv.type == MSG_BLOCK || inv.type == MSG_FILTERED_BLOCK || inv.type == MSG_CMPCT_BLOCK) { break; } } } pfrom->vRecvGetData.erase(pfrom->vRecvGetData.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. Currently only SPV clients // actually 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. connman->PushMessage(pfrom, msgMaker.Make(NetMsgType::NOTFOUND, vNotFound)); } } inline static void SendBlockTransactions(const CBlock &block, const BlockTransactionsRequest &req, CNode *pfrom, CConnman *connman) { BlockTransactions resp(req); for (size_t i = 0; i < req.indices.size(); i++) { if (req.indices[i] >= block.vtx.size()) { LOCK(cs_main); Misbehaving(pfrom, 100, "out-of-bound-tx-index"); LogPrintf( "Peer %d sent us a getblocktxn with out-of-bounds tx indices", pfrom->GetId()); return; } resp.txn[i] = block.vtx[req.indices[i]]; } LOCK(cs_main); const CNetMsgMaker msgMaker(pfrom->GetSendVersion()); int nSendFlags = 0; connman->PushMessage(pfrom, msgMaker.Make(nSendFlags, NetMsgType::BLOCKTXN, resp)); } static bool ProcessHeadersMessage(const Config &config, CNode *pfrom, CConnman *connman, const std::vector &headers, bool punish_duplicate_invalid) { const CChainParams &chainparams = config.GetChainParams(); const CNetMsgMaker msgMaker(pfrom->GetSendVersion()); size_t nCount = headers.size(); if (nCount == 0) { // Nothing interesting. Stop asking this peers for more headers. return true; } 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 (mapBlockIndex.find(headers[0].hashPrevBlock) == mapBlockIndex.end() && nCount < MAX_BLOCKS_TO_ANNOUNCE) { nodestate->nUnconnectingHeaders++; 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) { // The peer is sending us many headers we can't connect. Misbehaving(pfrom, 20, "too-many-unconnected-headers"); } return true; } uint256 hashLastBlock; for (const CBlockHeader &header : headers) { if (!hashLastBlock.IsNull() && header.hashPrevBlock != hashLastBlock) { Misbehaving(pfrom, 20, "disconnected-header"); return error("non-continuous headers sequence"); } 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 (mapBlockIndex.find(hashLastBlock) == mapBlockIndex.end()) { received_new_header = true; } } CValidationState state; CBlockHeader first_invalid_header; if (!ProcessNewBlockHeaders(config, headers, state, &pindexLast, &first_invalid_header)) { int nDoS; if (state.IsInvalid(nDoS)) { if (nDoS > 0) { LOCK(cs_main); Misbehaving(pfrom, nDoS, state.GetRejectReason()); } if (punish_duplicate_invalid && mapBlockIndex.find(first_invalid_header.GetHash()) != mapBlockIndex.end()) { // Goal: don't allow outbound peers to use up our outbound // connection slots if they are on incompatible chains. // // We ask the caller to set punish_invalid appropriately based // on the peer and the method of header delivery (compact blocks // are allowed to be invalid in some circumstances, under BIP // 152). // Here, we try to detect the narrow situation that we have a // valid block header (ie it was valid at the time the header // was received, and hence stored in mapBlockIndex) but know the // block is invalid, and that a peer has announced that same // block as being on its active chain. Disconnect the peer in // such a situation. // // Note: if the header that is invalid was not accepted to our // mapBlockIndex at all, that may also be grounds for // disconnecting the peer, as the chain they are on is likely to // be incompatible. However, there is a circumstance where that // does not hold: if the header's timestamp is more than 2 hours // ahead of our current time. In that case, the header may // become valid in the future, and we don't want to disconnect a // peer merely for serving us one too-far-ahead block header, to // prevent an attacker from splitting the network by mining a // block right at the 2 hour boundary. // // TODO: update the DoS logic (or, rather, rewrite the // DoS-interface between validation and net_processing) so that // the interface is cleaner, and so that we disconnect on all // the reasons that a peer's headers chain is incompatible with // ours (eg block->nVersion softforks, MTP violations, etc), and // not just the duplicate-invalid case. pfrom->fDisconnect = true; } return error("invalid header received"); } } { 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); connman->PushMessage( pfrom, msgMaker.Make(NetMsgType::GETHEADERS, chainActive.GetLocator(pindexLast), uint256())); } bool fCanDirectFetch = CanDirectFetch(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(BlockValidity::TREE) && chainActive.Tip()->nChainWork <= pindexLast->nChainWork) { std::vector 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.hasData() && !mapBlocksInFlight.count(pindexWalk->GetBlockHash())) { // 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 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; } vGetData.push_back(CInv(MSG_BLOCK, pindex->GetBlockHash())); MarkBlockAsInFlight(config, pfrom->GetId(), pindex->GetBlockHash(), chainparams.GetConsensus(), 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(BlockValidity::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); } 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 (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 using an outbound slot (unless // whitelisted or addnode). // 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 (IsOutboundDisconnectionCandidate(pfrom)) { LogPrintf("Disconnecting outbound peer %d -- headers " "chain has insufficient work\n", pfrom->GetId()); pfrom->fDisconnect = true; } } } if (!pfrom->fDisconnect && IsOutboundDisconnectionCandidate(pfrom) && nodestate->pindexBestKnownBlock != nullptr) { // If this is an outbound peer, check to see if we should protect it // from the bad/lagging chain logic. 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 true; } static bool ProcessMessage(const Config &config, CNode *pfrom, const std::string &strCommand, CDataStream &vRecv, int64_t nTimeReceived, CConnman *connman, const std::atomic &interruptMsgProc) { const CChainParams &chainparams = config.GetChainParams(); LogPrint(BCLog::NET, "received: %s (%u bytes) peer=%d\n", SanitizeString(strCommand), vRecv.size(), pfrom->GetId()); if (gArgs.IsArgSet("-dropmessagestest") && GetRand(gArgs.GetArg("-dropmessagestest", 0)) == 0) { LogPrintf("dropmessagestest DROPPING RECV MESSAGE\n"); return true; } if (!(pfrom->GetLocalServices() & NODE_BLOOM) && (strCommand == NetMsgType::FILTERLOAD || strCommand == NetMsgType::FILTERADD)) { if (pfrom->nVersion >= NO_BLOOM_VERSION) { LOCK(cs_main); Misbehaving(pfrom, 100, "no-bloom-version"); return false; } else { pfrom->fDisconnect = true; return false; } } if (strCommand == NetMsgType::REJECT) { if (LogAcceptCategory(BCLog::NET)) { try { std::string strMsg; uint8_t ccode; std::string strReason; vRecv >> LIMITED_STRING(strMsg, CMessageHeader::COMMAND_SIZE) >> ccode >> LIMITED_STRING(strReason, MAX_REJECT_MESSAGE_LENGTH); std::ostringstream ss; ss << strMsg << " code " << itostr(ccode) << ": " << strReason; if (strMsg == NetMsgType::BLOCK || strMsg == NetMsgType::TX) { uint256 hash; vRecv >> hash; ss << ": hash " << hash.ToString(); } LogPrint(BCLog::NET, "Reject %s\n", SanitizeString(ss.str())); } catch (const std::ios_base::failure &) { // Avoid feedback loops by preventing reject messages from // triggering a new reject message. LogPrint(BCLog::NET, "Unparseable reject message received\n"); } } } else if (strCommand == NetMsgType::VERSION) { // Each connection can only send one version message if (pfrom->nVersion != 0) { connman->PushMessage( pfrom, CNetMsgMaker(INIT_PROTO_VERSION) .Make(NetMsgType::REJECT, strCommand, REJECT_DUPLICATE, std::string("Duplicate version message"))); LOCK(cs_main); Misbehaving(pfrom, 1, "multiple-version"); return false; } int64_t nTime; CAddress addrMe; CAddress addrFrom; uint64_t nNonce = 1; uint64_t nServiceInt; ServiceFlags nServices; int nVersion; int nSendVersion; std::string strSubVer; std::string cleanSubVer; int nStartingHeight = -1; bool fRelay = true; vRecv >> nVersion >> nServiceInt >> nTime >> addrMe; nSendVersion = std::min(nVersion, PROTOCOL_VERSION); nServices = ServiceFlags(nServiceInt); if (!pfrom->fInbound) { connman->SetServices(pfrom->addr, nServices); } if (!pfrom->fInbound && !pfrom->fFeeler && !pfrom->m_manual_connection && !HasAllDesirableServiceFlags(nServices)) { LogPrint( BCLog::NET, "peer=%d does not offer the expected services " "(%08x offered, %08x expected); disconnecting\n", pfrom->GetId(), nServices, GetDesirableServiceFlags(nServices)); connman->PushMessage( pfrom, CNetMsgMaker(INIT_PROTO_VERSION) .Make(NetMsgType::REJECT, strCommand, REJECT_NONSTANDARD, strprintf("Expected to offer services %08x", GetDesirableServiceFlags(nServices)))); pfrom->fDisconnect = true; return false; } if (nVersion < MIN_PEER_PROTO_VERSION) { // disconnect from peers older than this proto version LogPrintf("peer=%d using obsolete version %i; disconnecting\n", pfrom->GetId(), nVersion); connman->PushMessage( pfrom, CNetMsgMaker(INIT_PROTO_VERSION) .Make(NetMsgType::REJECT, strCommand, REJECT_OBSOLETE, strprintf("Version must be %d or greater", MIN_PEER_PROTO_VERSION))); pfrom->fDisconnect = true; return false; } if (!vRecv.empty()) { vRecv >> addrFrom >> nNonce; } if (!vRecv.empty()) { 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->fInbound && !connman->CheckIncomingNonce(nNonce)) { LogPrintf("connected to self at %s, disconnecting\n", pfrom->addr.ToString()); pfrom->fDisconnect = true; return true; } if (pfrom->fInbound && addrMe.IsRoutable()) { SeenLocal(addrMe); } // Be shy and don't send version until we hear if (pfrom->fInbound) { PushNodeVersion(config, pfrom, connman, GetAdjustedTime()); } connman->PushMessage( pfrom, CNetMsgMaker(INIT_PROTO_VERSION).Make(NetMsgType::VERACK)); pfrom->nServices = nServices; pfrom->SetAddrLocal(addrMe); { LOCK(pfrom->cs_SubVer); pfrom->strSubVer = strSubVer; pfrom->cleanSubVer = cleanSubVer; } pfrom->nStartingHeight = nStartingHeight; pfrom->fClient = !(nServices & NODE_NETWORK); { LOCK(pfrom->cs_filter); // set to true after we get the first filter* message pfrom->fRelayTxes = fRelay; } // Change version pfrom->SetSendVersion(nSendVersion); pfrom->nVersion = nVersion; // Potentially mark this peer as a preferred download peer. { LOCK(cs_main); UpdatePreferredDownload(pfrom, State(pfrom->GetId())); } if (!pfrom->fInbound) { // Advertise our address if (fListen && !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 if (pfrom->fOneShot || pfrom->nVersion >= CADDR_TIME_VERSION || connman->GetAddressCount() < 1000) { connman->PushMessage( pfrom, CNetMsgMaker(nSendVersion).Make(NetMsgType::GETADDR)); pfrom->fGetAddr = true; } connman->MarkAddressGood(pfrom->addr); } std::string remoteAddr; if (fLogIPs) { remoteAddr = ", peeraddr=" + pfrom->addr.ToString(); } LogPrintf("receive version message: [%s] %s: version %d, blocks=%d, " "us=%s, peer=%d%s\n", pfrom->addr.ToString().c_str(), 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 (pfrom->nVersion <= 70012) { CDataStream finalAlert( ParseHex("60010000000000000000000000ffffff7f00000000ffffff7ffef" "fff7f01ffffff7f00000000ffffff7f00ffffff7f002f55524745" "4e543a20416c657274206b657920636f6d70726f6d697365642c2" "075706772616465207265717569726564004630440220653febd6" "410f470f6bae11cad19c48413becb1ac2c17f908fd0fd53bdc3ab" "d5202206d0e9c96fe88d4a0f01ed9dedae2b6f9e00da94cad0fec" "aae66ecf689bf71b50"), SER_NETWORK, PROTOCOL_VERSION); connman->PushMessage( pfrom, CNetMsgMaker(nSendVersion).Make("alert", finalAlert)); } // Feeler connections exist only to verify if address is online. if (pfrom->fFeeler) { assert(pfrom->fInbound == false); pfrom->fDisconnect = true; } return true; } else if (pfrom->nVersion == 0) { // Must have a version message before anything else LOCK(cs_main); Misbehaving(pfrom, 1, "missing-version"); return false; } // At this point, the outgoing message serialization version can't change. const CNetMsgMaker msgMaker(pfrom->GetSendVersion()); if (strCommand == NetMsgType::VERACK) { pfrom->SetRecvVersion( std::min(pfrom->nVersion.load(), PROTOCOL_VERSION)); if (!pfrom->fInbound) { // Mark this node as currently connected, so we update its timestamp // later. LOCK(cs_main); State(pfrom->GetId())->fCurrentlyConnected = true; } if (pfrom->nVersion >= 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) connman->PushMessage(pfrom, msgMaker.Make(NetMsgType::SENDHEADERS)); } if (pfrom->nVersion >= 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 = 1; connman->PushMessage(pfrom, msgMaker.Make(NetMsgType::SENDCMPCT, fAnnounceUsingCMPCTBLOCK, nCMPCTBLOCKVersion)); } pfrom->fSuccessfullyConnected = true; } else if (!pfrom->fSuccessfullyConnected) { // Must have a verack message before anything else LOCK(cs_main); Misbehaving(pfrom, 1, "missing-verack"); return false; } else if (strCommand == NetMsgType::ADDR) { std::vector vAddr; vRecv >> vAddr; // Don't want addr from older versions unless seeding if (pfrom->nVersion < CADDR_TIME_VERSION && connman->GetAddressCount() > 1000) { return true; } if (vAddr.size() > 1000) { LOCK(cs_main); Misbehaving(pfrom, 20, "oversized-addr"); return error("message addr size() = %u", vAddr.size()); } // Store the new addresses std::vector vAddrOk; int64_t nNow = GetAdjustedTime(); int64_t nSince = nNow - 10 * 60; for (CAddress &addr : vAddr) { if (interruptMsgProc) { return true; } // 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)) { continue; } if (addr.nTime <= 100000000 || addr.nTime > nNow + 10 * 60) { addr.nTime = nNow - 5 * 24 * 60 * 60; } pfrom->AddAddressKnown(addr); 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, connman); } // Do not store addresses outside our network if (fReachable) { vAddrOk.push_back(addr); } } connman->AddNewAddresses(vAddrOk, pfrom->addr, 2 * 60 * 60); if (vAddr.size() < 1000) { pfrom->fGetAddr = false; } if (pfrom->fOneShot) { pfrom->fDisconnect = true; } } else if (strCommand == NetMsgType::SENDHEADERS) { LOCK(cs_main); State(pfrom->GetId())->fPreferHeaders = true; } else if (strCommand == NetMsgType::SENDCMPCT) { bool fAnnounceUsingCMPCTBLOCK = false; uint64_t nCMPCTBLOCKVersion = 0; vRecv >> fAnnounceUsingCMPCTBLOCK >> nCMPCTBLOCKVersion; if (nCMPCTBLOCKVersion == 1) { LOCK(cs_main); // fProvidesHeaderAndIDs is used to "lock in" version of compact // blocks we send. if (!State(pfrom->GetId())->fProvidesHeaderAndIDs) { State(pfrom->GetId())->fProvidesHeaderAndIDs = true; } State(pfrom->GetId())->fPreferHeaderAndIDs = fAnnounceUsingCMPCTBLOCK; if (!State(pfrom->GetId())->fSupportsDesiredCmpctVersion) { State(pfrom->GetId())->fSupportsDesiredCmpctVersion = true; } } } else if (strCommand == NetMsgType::INV) { std::vector vInv; vRecv >> vInv; if (vInv.size() > MAX_INV_SZ) { LOCK(cs_main); Misbehaving(pfrom, 20, "oversized-inv"); return error("message inv size() = %u", vInv.size()); } bool fBlocksOnly = !fRelayTxes; // Allow whitelisted peers to send data other than blocks in blocks only // mode if whitelistrelay is true if (pfrom->fWhitelisted && gArgs.GetBoolArg("-whitelistrelay", DEFAULT_WHITELISTRELAY)) { fBlocksOnly = false; } LOCK(cs_main); std::vector vToFetch; for (CInv &inv : vInv) { if (interruptMsgProc) { return true; } bool fAlreadyHave = AlreadyHave(inv); LogPrint(BCLog::NET, "got inv: %s %s peer=%d\n", inv.ToString(), fAlreadyHave ? "have" : "new", pfrom->GetId()); if (inv.type == MSG_BLOCK) { UpdateBlockAvailability(pfrom->GetId(), inv.hash); if (!fAlreadyHave && !fImporting && !fReindex && !mapBlocksInFlight.count(inv.hash)) { // We used to request the full block here, but since // headers-announcements are now the primary method of // announcement on the network, and since, in the case that // a node fell back to inv we probably have a reorg which we // should get the headers for first, we now only provide a // getheaders response here. When we receive the headers, we // will then ask for the blocks we need. connman->PushMessage( pfrom, msgMaker.Make(NetMsgType::GETHEADERS, chainActive.GetLocator(pindexBestHeader), inv.hash)); LogPrint(BCLog::NET, "getheaders (%d) %s to peer=%d\n", pindexBestHeader->nHeight, inv.hash.ToString(), pfrom->GetId()); } } else { pfrom->AddInventoryKnown(inv); if (fBlocksOnly) { LogPrint(BCLog::NET, "transaction (%s) inv sent in " "violation of protocol peer=%d\n", inv.hash.ToString(), pfrom->GetId()); } else if (!fAlreadyHave && !fImporting && !fReindex && !IsInitialBlockDownload()) { pfrom->AskFor(inv); } } // Track requests for our stuff GetMainSignals().Inventory(inv.hash); } if (!vToFetch.empty()) { connman->PushMessage(pfrom, msgMaker.Make(NetMsgType::GETDATA, vToFetch)); } } else if (strCommand == NetMsgType::GETDATA) { std::vector vInv; vRecv >> vInv; if (vInv.size() > MAX_INV_SZ) { LOCK(cs_main); Misbehaving(pfrom, 20, "too-many-inv"); return error("message getdata size() = %u", vInv.size()); } 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()); } pfrom->vRecvGetData.insert(pfrom->vRecvGetData.end(), vInv.begin(), vInv.end()); ProcessGetData(config, pfrom, connman, interruptMsgProc); } else if (strCommand == NetMsgType::GETBLOCKS) { CBlockLocator locator; uint256 hashStop; vRecv >> locator >> hashStop; // 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 a_recent_block; { LOCK(cs_most_recent_block); a_recent_block = most_recent_block; } CValidationState dummy; ActivateBestChain(config, dummy, a_recent_block); } 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 / chainparams.GetConsensus().nPowTargetSpacing; if (fPruneMode && (!pindex->nStatus.hasData() || 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; } pfrom->PushInventory(CInv(MSG_BLOCK, 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; } } } else if (strCommand == NetMsgType::GETBLOCKTXN) { BlockTransactionsRequest req; vRecv >> req; std::shared_ptr 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(*recent_block, req, pfrom, connman); return true; } LOCK(cs_main); BlockMap::iterator it = mapBlockIndex.find(req.blockhash); if (it == mapBlockIndex.end() || !it->second->nStatus.hasData()) { LogPrintf("Peer %d sent us a getblocktxn for a block we don't have", pfrom->GetId()); return true; } if (it->second->nHeight < chainActive.Height() - MAX_BLOCKTXN_DEPTH) { // 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", pfrom->GetId(), MAX_BLOCKTXN_DEPTH); CInv inv; inv.type = MSG_BLOCK; inv.hash = req.blockhash; pfrom->vRecvGetData.push_back(inv); ProcessGetData(config, pfrom, connman, interruptMsgProc); return true; } CBlock block; bool ret = ReadBlockFromDisk(block, it->second, config); assert(ret); SendBlockTransactions(block, req, pfrom, connman); } else if (strCommand == NetMsgType::GETHEADERS) { CBlockLocator locator; uint256 hashStop; vRecv >> locator >> hashStop; LOCK(cs_main); if (IsInitialBlockDownload() && !pfrom->fWhitelisted) { LogPrint(BCLog::NET, "Ignoring getheaders from peer=%d because " "node is in initial block download\n", pfrom->GetId()); return true; } CNodeState *nodestate = State(pfrom->GetId()); const CBlockIndex *pindex = nullptr; if (locator.IsNull()) { // If locator is null, return the hashStop block BlockMap::iterator mi = mapBlockIndex.find(hashStop); if (mi == mapBlockIndex.end()) { return true; } pindex = (*mi).second; + + if (!chainActive.Contains(pindex) && + !StaleBlockRequestAllowed(pindex, chainparams.GetConsensus())) { + LogPrintf("%s: ignoring request from peer=%i for old block " + "header that isn't in the main chain\n", + __func__, pfrom->GetId()); + return true; + } } 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 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(); connman->PushMessage(pfrom, msgMaker.Make(NetMsgType::HEADERS, vHeaders)); } else if (strCommand == NetMsgType::TX) { // Stop processing the transaction early if // We are in blocks only mode and peer is either not whitelisted or // whitelistrelay is off if (!fRelayTxes && (!pfrom->fWhitelisted || !gArgs.GetBoolArg("-whitelistrelay", DEFAULT_WHITELISTRELAY))) { LogPrint(BCLog::NET, "transaction sent in violation of protocol peer=%d\n", pfrom->GetId()); return true; } std::deque vWorkQueue; std::vector vEraseQueue; CTransactionRef ptx; vRecv >> ptx; const CTransaction &tx = *ptx; CInv inv(MSG_TX, tx.GetId()); pfrom->AddInventoryKnown(inv); LOCK(cs_main); bool fMissingInputs = false; CValidationState state; pfrom->setAskFor.erase(inv.hash); mapAlreadyAskedFor.erase(inv.hash); if (!AlreadyHave(inv) && AcceptToMemoryPool(config, g_mempool, state, ptx, true, &fMissingInputs)) { g_mempool.check(pcoinsTip.get()); RelayTransaction(tx, connman); for (size_t i = 0; i < tx.vout.size(); i++) { vWorkQueue.emplace_back(inv.hash, i); } pfrom->nLastTXTime = GetTime(); LogPrint(BCLog::MEMPOOL, "AcceptToMemoryPool: peer=%d: accepted %s " "(poolsz %u txn, %u kB)\n", pfrom->GetId(), tx.GetId().ToString(), g_mempool.size(), g_mempool.DynamicMemoryUsage() / 1000); // Recursively process any orphan transactions that depended on this // one std::set setMisbehaving; while (!vWorkQueue.empty()) { auto itByPrev = mapOrphanTransactionsByPrev.find(vWorkQueue.front()); vWorkQueue.pop_front(); if (itByPrev == mapOrphanTransactionsByPrev.end()) { continue; } for (auto mi = itByPrev->second.begin(); mi != itByPrev->second.end(); ++mi) { const CTransactionRef &porphanTx = (*mi)->second.tx; const CTransaction &orphanTx = *porphanTx; const uint256 &orphanId = orphanTx.GetId(); NodeId fromPeer = (*mi)->second.fromPeer; bool fMissingInputs2 = false; // Use a dummy CValidationState so someone can't setup nodes // to counter-DoS based on orphan resolution (that is, // feeding people an invalid transaction based on LegitTxX // in order to get anyone relaying LegitTxX banned) CValidationState stateDummy; if (setMisbehaving.count(fromPeer)) { continue; } if (AcceptToMemoryPool(config, g_mempool, stateDummy, porphanTx, true, &fMissingInputs2)) { LogPrint(BCLog::MEMPOOL, " accepted orphan tx %s\n", orphanId.ToString()); RelayTransaction(orphanTx, connman); for (size_t i = 0; i < orphanTx.vout.size(); i++) { vWorkQueue.emplace_back(orphanId, i); } vEraseQueue.push_back(orphanId); } else if (!fMissingInputs2) { int nDos = 0; if (stateDummy.IsInvalid(nDos) && nDos > 0) { // Punish peer that gave us an invalid orphan tx Misbehaving(fromPeer, nDos, "invalid-orphan-tx"); setMisbehaving.insert(fromPeer); LogPrint(BCLog::MEMPOOL, " invalid orphan tx %s\n", orphanId.ToString()); } // Has inputs but not accepted to mempool // Probably non-standard or insufficient fee/priority LogPrint(BCLog::MEMPOOL, " removed orphan tx %s\n", orphanId.ToString()); vEraseQueue.push_back(orphanId); if (!stateDummy.CorruptionPossible()) { // Do not use rejection cache for witness // transactions or witness-stripped transactions, as // they can have been malleated. See // https://github.com/bitcoin/bitcoin/issues/8279 // for details. assert(recentRejects); recentRejects->insert(orphanId); } } g_mempool.check(pcoinsTip.get()); } } for (const uint256 &hash : vEraseQueue) { EraseOrphanTx(hash); } } else if (fMissingInputs) { // It may be the case that the orphans parents have all been // rejected. bool fRejectedParents = false; for (const CTxIn &txin : tx.vin) { if (recentRejects->contains(txin.prevout.GetTxId())) { fRejectedParents = true; break; } } if (!fRejectedParents) { for (const CTxIn &txin : tx.vin) { // FIXME: MSG_TX should use a TxHash, not a TxId. CInv _inv(MSG_TX, txin.prevout.GetTxId()); pfrom->AddInventoryKnown(_inv); if (!AlreadyHave(_inv)) { pfrom->AskFor(_inv); } } AddOrphanTx(ptx, pfrom->GetId()); // DoS prevention: do not allow mapOrphanTransactions to grow // unbounded 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.GetId().ToString()); // We will continue to reject this tx since it has rejected // parents so avoid re-requesting it from other peers. recentRejects->insert(tx.GetId()); } } else { if (!state.CorruptionPossible()) { // Do not use rejection cache for witness transactions or // witness-stripped transactions, as they can have been // malleated. See https://github.com/bitcoin/bitcoin/issues/8279 // for details. assert(recentRejects); recentRejects->insert(tx.GetId()); if (RecursiveDynamicUsage(*ptx) < 100000) { AddToCompactExtraTransactions(ptx); } } if (pfrom->fWhitelisted && gArgs.GetBoolArg("-whitelistforcerelay", DEFAULT_WHITELISTFORCERELAY)) { // Always relay transactions received from whitelisted peers, // even if they were already in the mempool or rejected from it // due to policy, allowing the node to function as a gateway for // nodes hidden behind it. // // Never relay transactions that we would assign a non-zero DoS // score for, as we expect peers to do the same with us in that // case. int nDoS = 0; if (!state.IsInvalid(nDoS) || nDoS == 0) { LogPrintf("Force relaying tx %s from whitelisted peer=%d\n", tx.GetId().ToString(), pfrom->GetId()); RelayTransaction(tx, connman); } else { LogPrintf("Not relaying invalid transaction %s from " "whitelisted peer=%d (%s)\n", tx.GetId().ToString(), pfrom->GetId(), FormatStateMessage(state)); } } } int nDoS = 0; if (state.IsInvalid(nDoS)) { LogPrint(BCLog::MEMPOOLREJ, "%s from peer=%d was not accepted: %s\n", tx.GetHash().ToString(), pfrom->GetId(), FormatStateMessage(state)); // Never send AcceptToMemoryPool's internal codes over P2P. if (state.GetRejectCode() > 0 && state.GetRejectCode() < REJECT_INTERNAL) { connman->PushMessage( pfrom, msgMaker.Make(NetMsgType::REJECT, strCommand, uint8_t(state.GetRejectCode()), state.GetRejectReason().substr( 0, MAX_REJECT_MESSAGE_LENGTH), inv.hash)); } if (nDoS > 0) { Misbehaving(pfrom, nDoS, state.GetRejectReason()); } } } // Ignore blocks received while importing else if (strCommand == NetMsgType::CMPCTBLOCK && !fImporting && !fReindex) { CBlockHeaderAndShortTxIDs cmpctblock; vRecv >> cmpctblock; bool received_new_header = false; { LOCK(cs_main); if (mapBlockIndex.find(cmpctblock.header.hashPrevBlock) == mapBlockIndex.end()) { // Doesn't connect (or is genesis), instead of DoSing in // AcceptBlockHeader, request deeper headers if (!IsInitialBlockDownload()) { connman->PushMessage( pfrom, msgMaker.Make(NetMsgType::GETHEADERS, chainActive.GetLocator(pindexBestHeader), uint256())); } return true; } if (mapBlockIndex.find(cmpctblock.header.GetHash()) == mapBlockIndex.end()) { received_new_header = true; } } const CBlockIndex *pindex = nullptr; CValidationState state; if (!ProcessNewBlockHeaders(config, {cmpctblock.header}, state, &pindex)) { int nDoS; if (state.IsInvalid(nDoS)) { if (nDoS > 0) { LOCK(cs_main); Misbehaving(pfrom, nDoS, state.GetRejectReason()); } LogPrintf("Peer %d sent us invalid header via cmpctblock\n", pfrom->GetId()); return true; } } // 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 pblock = std::make_shared(); bool fBlockReconstructed = false; { LOCK(cs_main); // 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::iterator>>:: iterator blockInFlightIt = mapBlocksInFlight.find(pindex->GetBlockHash()); bool fAlreadyInFlight = blockInFlightIt != mapBlocksInFlight.end(); if (pindex->nStatus.hasData()) { // Nothing to do here return true; } 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 vInv(1); vInv[0] = CInv(MSG_BLOCK, cmpctblock.header.GetHash()); connman->PushMessage( pfrom, msgMaker.Make(NetMsgType::GETDATA, vInv)); } return true; } // If we're not close to tip yet, give up and let parallel block // fetch work its magic. if (!fAlreadyInFlight && !CanDirectFetch(chainparams.GetConsensus())) { return true; } // 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::iterator *queuedBlockIt = nullptr; if (!MarkBlockAsInFlight(config, pfrom->GetId(), pindex->GetBlockHash(), chainparams.GetConsensus(), pindex, &queuedBlockIt)) { if (!(*queuedBlockIt)->partialBlock) { (*queuedBlockIt) ->partialBlock.reset( new PartiallyDownloadedBlock(config, &g_mempool)); } 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 true; } } PartiallyDownloadedBlock &partialBlock = *(*queuedBlockIt)->partialBlock; ReadStatus status = partialBlock.InitData(cmpctblock, vExtraTxnForCompact); if (status == READ_STATUS_INVALID) { // Reset in-flight state in case of whitelist MarkBlockAsReceived(pindex->GetBlockHash()); Misbehaving(pfrom, 100, "invalid-cmpctblk"); LogPrintf("Peer %d sent us invalid compact block\n", pfrom->GetId()); return true; } else if (status == READ_STATUS_FAILED) { // Duplicate txindices, the block is now in-flight, so // just request it. std::vector vInv(1); vInv[0] = CInv(MSG_BLOCK, cmpctblock.header.GetHash()); connman->PushMessage( pfrom, msgMaker.Make(NetMsgType::GETDATA, vInv)); return true; } BlockTransactionsRequest req; for (size_t i = 0; i < cmpctblock.BlockTxCount(); i++) { if (!partialBlock.IsTxAvailable(i)) { req.indices.push_back(i); } } if (req.indices.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(); 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(config, &g_mempool); ReadStatus status = tempBlock.InitData(cmpctblock, vExtraTxnForCompact); if (status != READ_STATUS_OK) { // TODO: don't ignore failures return true; } std::vector 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 vInv(1); vInv[0] = CInv(MSG_BLOCK, cmpctblock.header.GetHash()); connman->PushMessage( pfrom, msgMaker.Make(NetMsgType::GETDATA, vInv)); return true; } else { // If this was an announce-cmpctblock, we want the same // treatment as a header message. fRevertToHeaderProcessing = true; } } } // cs_main if (fProcessBLOCKTXN) { return ProcessMessage(config, pfrom, NetMsgType::BLOCKTXN, blockTxnMsg, nTimeReceived, connman, 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 banned. return ProcessHeadersMessage(config, pfrom, connman, {cmpctblock.header}, /*punish_duplicate_invalid=*/false); } 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. ProcessNewBlock(config, pblock, /*fForceProcessing=*/true, &fNewBlock); if (fNewBlock) { pfrom->nLastBlockTime = GetTime(); } // hold cs_main for CBlockIndex::IsValid() LOCK(cs_main); if (pindex->IsValid(BlockValidity::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()); } } } else if (strCommand == NetMsgType::BLOCKTXN && !fImporting && !fReindex) // Ignore blocks received while importing { BlockTransactions resp; vRecv >> resp; std::shared_ptr pblock = std::make_shared(); bool fBlockRead = false; { LOCK(cs_main); std::map::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 true; } PartiallyDownloadedBlock &partialBlock = *it->second.second->partialBlock; ReadStatus status = partialBlock.FillBlock(*pblock, resp.txn); if (status == READ_STATUS_INVALID) { // Reset in-flight state in case of whitelist. MarkBlockAsReceived(resp.blockhash); Misbehaving(pfrom, 100, "invalid-cmpctblk-txns"); LogPrintf("Peer %d sent us invalid compact block/non-matching " "block transactions\n", pfrom->GetId()); return true; } else if (status == READ_STATUS_FAILED) { // Might have collided, fall back to getdata now :( std::vector invs; invs.push_back(CInv(MSG_BLOCK, resp.blockhash)); 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 DoS-ban 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, reject messages go out, etc. // it is now an empty pointer MarkBlockAsReceived(resp.blockhash); fBlockRead = true; // mapBlockSource is only used for sending reject messages and // DoS scores, 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. ProcessNewBlock(config, pblock, /*fForceProcessing=*/true, &fNewBlock); if (fNewBlock) { pfrom->nLastBlockTime = GetTime(); } } } // Ignore headers received while importing else if (strCommand == NetMsgType::HEADERS && !fImporting && !fReindex) { std::vector 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) { LOCK(cs_main); Misbehaving(pfrom, 20, "too-many-headers"); return error("headers message size = %u", nCount); } headers.resize(nCount); for (unsigned int n = 0; n < nCount; n++) { vRecv >> headers[n]; // Ignore tx count; assume it is 0. ReadCompactSize(vRecv); } // Headers received via a HEADERS message should be valid, and reflect // the chain the peer is on. If we receive a known-invalid header, // disconnect the peer if it is using one of our outbound connection // slots. bool should_punish = !pfrom->fInbound && !pfrom->m_manual_connection; return ProcessHeadersMessage(config, pfrom, connman, headers, should_punish); } else if (strCommand == NetMsgType::BLOCK && !fImporting && !fReindex) { // Ignore blocks received while importing. std::shared_ptr pblock = std::make_shared(); vRecv >> *pblock; LogPrint(BCLog::NET, "received block %s peer=%d\n", pblock->GetHash().ToString(), pfrom->GetId()); // Process all blocks from whitelisted peers, even if not requested, // unless we're still syncing with the network. Such an unrequested // block may still be processed, subject to the conditions in // AcceptBlock(). bool forceProcessing = pfrom->fWhitelisted && !IsInitialBlockDownload(); 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); // mapBlockSource is only used for sending reject messages and DoS // scores, so the race between here and cs_main in ProcessNewBlock // is fine. mapBlockSource.emplace(hash, std::make_pair(pfrom->GetId(), true)); } bool fNewBlock = false; ProcessNewBlock(config, pblock, forceProcessing, &fNewBlock); if (fNewBlock) { pfrom->nLastBlockTime = GetTime(); } } else if (strCommand == 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->fInbound) { LogPrint(BCLog::NET, "Ignoring \"getaddr\" from outbound connection. peer=%d\n", pfrom->GetId()); return true; } // 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 true; } pfrom->fSentAddr = true; pfrom->vAddrToSend.clear(); std::vector vAddr = connman->GetAddresses(); FastRandomContext insecure_rand; for (const CAddress &addr : vAddr) { pfrom->PushAddress(addr, insecure_rand); } } else if (strCommand == NetMsgType::MEMPOOL) { if (!(pfrom->GetLocalServices() & NODE_BLOOM) && !pfrom->fWhitelisted) { LogPrint(BCLog::NET, "mempool request with bloom filters disabled, " "disconnect peer=%d\n", pfrom->GetId()); pfrom->fDisconnect = true; return true; } if (connman->OutboundTargetReached(false) && !pfrom->fWhitelisted) { LogPrint(BCLog::NET, "mempool request with bandwidth limit " "reached, disconnect peer=%d\n", pfrom->GetId()); pfrom->fDisconnect = true; return true; } LOCK(pfrom->cs_inventory); pfrom->fSendMempool = true; } else if (strCommand == NetMsgType::PING) { if (pfrom->nVersion > 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. connman->PushMessage(pfrom, msgMaker.Make(NetMsgType::PONG, nonce)); } } else if (strCommand == NetMsgType::PONG) { int64_t pingUsecEnd = nTimeReceived; 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; int64_t pingUsecTime = pingUsecEnd - pfrom->nPingUsecStart; if (pingUsecTime > 0) { // Successful ping time measurement, replace previous pfrom->nPingUsecTime = pingUsecTime; pfrom->nMinPingUsecTime = std::min( pfrom->nMinPingUsecTime.load(), pingUsecTime); } 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; } } else if (strCommand == NetMsgType::FILTERLOAD) { CBloomFilter filter; vRecv >> filter; if (!filter.IsWithinSizeConstraints()) { // There is no excuse for sending a too-large filter LOCK(cs_main); Misbehaving(pfrom, 100, "oversized-bloom-filter"); } else { LOCK(pfrom->cs_filter); pfrom->pfilter.reset(new CBloomFilter(filter)); pfrom->pfilter->UpdateEmptyFull(); pfrom->fRelayTxes = true; } } else if (strCommand == NetMsgType::FILTERADD) { std::vector 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 { LOCK(pfrom->cs_filter); if (pfrom->pfilter) { pfrom->pfilter->insert(vData); } else { bad = true; } } if (bad) { LOCK(cs_main); // The structure of this code doesn't really allow for a good error // code. We'll go generic. Misbehaving(pfrom, 100, "invalid-filteradd"); } } else if (strCommand == NetMsgType::FILTERCLEAR) { LOCK(pfrom->cs_filter); if (pfrom->GetLocalServices() & NODE_BLOOM) { pfrom->pfilter.reset(new CBloomFilter()); } pfrom->fRelayTxes = true; } else if (strCommand == NetMsgType::FEEFILTER) { Amount newFeeFilter = Amount::zero(); vRecv >> newFeeFilter; if (MoneyRange(newFeeFilter)) { { LOCK(pfrom->cs_feeFilter); pfrom->minFeeFilter = newFeeFilter; } LogPrint(BCLog::NET, "received: feefilter of %s from peer=%d\n", CFeeRate(newFeeFilter).ToString(), pfrom->GetId()); } } else if (strCommand == NetMsgType::NOTFOUND) { // We do not care about the NOTFOUND message, but logging an Unknown // Command message would be undesirable as we transmit it ourselves. } else { // Ignore unknown commands for extensibility LogPrint(BCLog::NET, "Unknown command \"%s\" from peer=%d\n", SanitizeString(strCommand), pfrom->GetId()); } return true; } static bool SendRejectsAndCheckIfBanned(CNode *pnode, CConnman *connman) { AssertLockHeld(cs_main); CNodeState &state = *State(pnode->GetId()); for (const CBlockReject &reject : state.rejects) { connman->PushMessage( pnode, CNetMsgMaker(INIT_PROTO_VERSION) .Make(NetMsgType::REJECT, std::string(NetMsgType::BLOCK), reject.chRejectCode, reject.strRejectReason, reject.hashBlock)); } state.rejects.clear(); if (state.fShouldBan) { state.fShouldBan = false; if (pnode->fWhitelisted) { LogPrintf("Warning: not punishing whitelisted peer %s!\n", pnode->addr.ToString()); } else if (pnode->m_manual_connection) { LogPrintf("Warning: not punishing manually-connected peer %s!\n", pnode->addr.ToString()); } else { pnode->fDisconnect = true; if (pnode->addr.IsLocal()) { LogPrintf("Warning: not banning local peer %s!\n", pnode->addr.ToString()); } else { connman->Ban(pnode->addr, BanReasonNodeMisbehaving); } } return true; } return false; } bool PeerLogicValidation::ProcessMessages(const Config &config, CNode *pfrom, std::atomic &interruptMsgProc) { const CChainParams &chainparams = config.GetChainParams(); // // Message format // (4) message start // (12) command // (4) size // (4) checksum // (x) data // bool fMoreWork = false; if (!pfrom->vRecvGetData.empty()) { ProcessGetData(config, pfrom, connman, interruptMsgProc); } if (pfrom->fDisconnect) { return false; } // this maintains the order of responses if (!pfrom->vRecvGetData.empty()) { return true; } // Don't bother if send buffer is too full to respond anyway if (pfrom->fPauseSend) { return false; } std::list 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().vRecv.size() + CMessageHeader::HEADER_SIZE; pfrom->fPauseRecv = pfrom->nProcessQueueSize > connman->GetReceiveFloodSize(); fMoreWork = !pfrom->vProcessMsg.empty(); } CNetMessage &msg(msgs.front()); msg.SetVersion(pfrom->GetRecvVersion()); // Scan for message start if (memcmp(std::begin(msg.hdr.pchMessageStart), std::begin(chainparams.NetMagic()), CMessageHeader::MESSAGE_START_SIZE) != 0) { LogPrintf("PROCESSMESSAGE: INVALID MESSAGESTART %s peer=%d\n", SanitizeString(msg.hdr.GetCommand()), pfrom->GetId()); // Make sure we ban where that come from for some time. connman->Ban(pfrom->addr, BanReasonNodeMisbehaving); pfrom->fDisconnect = true; return false; } // Read header CMessageHeader &hdr = msg.hdr; if (!hdr.IsValid(config)) { LogPrintf("PROCESSMESSAGE: ERRORS IN HEADER %s peer=%d\n", SanitizeString(hdr.GetCommand()), pfrom->GetId()); return fMoreWork; } std::string strCommand = hdr.GetCommand(); // Message size unsigned int nMessageSize = hdr.nMessageSize; // Checksum CDataStream &vRecv = msg.vRecv; const uint256 &hash = msg.GetMessageHash(); if (memcmp(hash.begin(), hdr.pchChecksum, CMessageHeader::CHECKSUM_SIZE) != 0) { LogPrintf( "%s(%s, %u bytes): CHECKSUM ERROR expected %s was %s\n", __func__, SanitizeString(strCommand), nMessageSize, HexStr(hash.begin(), hash.begin() + CMessageHeader::CHECKSUM_SIZE), HexStr(hdr.pchChecksum, hdr.pchChecksum + CMessageHeader::CHECKSUM_SIZE)); return fMoreWork; } // Process message bool fRet = false; try { fRet = ProcessMessage(config, pfrom, strCommand, vRecv, msg.nTime, connman, interruptMsgProc); if (interruptMsgProc) { return false; } if (!pfrom->vRecvGetData.empty()) { fMoreWork = true; } } catch (const std::ios_base::failure &e) { connman->PushMessage(pfrom, CNetMsgMaker(INIT_PROTO_VERSION) .Make(NetMsgType::REJECT, strCommand, REJECT_MALFORMED, std::string("error parsing message"))); if (strstr(e.what(), "end of data")) { // Allow exceptions from under-length message on vRecv LogPrintf( "%s(%s, %u bytes): Exception '%s' caught, normally caused by a " "message being shorter than its stated length\n", __func__, SanitizeString(strCommand), nMessageSize, e.what()); } else if (strstr(e.what(), "size too large")) { // Allow exceptions from over-long size LogPrintf("%s(%s, %u bytes): Exception '%s' caught\n", __func__, SanitizeString(strCommand), nMessageSize, e.what()); } else if (strstr(e.what(), "non-canonical ReadCompactSize()")) { // Allow exceptions from non-canonical encoding LogPrintf("%s(%s, %u bytes): Exception '%s' caught\n", __func__, SanitizeString(strCommand), nMessageSize, e.what()); } else { PrintExceptionContinue(&e, "ProcessMessages()"); } } catch (const std::exception &e) { PrintExceptionContinue(&e, "ProcessMessages()"); } catch (...) { PrintExceptionContinue(nullptr, "ProcessMessages()"); } if (!fRet) { LogPrintf("%s(%s, %u bytes) FAILED peer=%d\n", __func__, SanitizeString(strCommand), nMessageSize, pfrom->GetId()); } LOCK(cs_main); SendRejectsAndCheckIfBanned(pfrom, connman); return fMoreWork; } void PeerLogicValidation::ConsiderEviction(CNode *pto, int64_t time_in_seconds) { AssertLockHeld(cs_main); CNodeState &state = *State(pto->GetId()); const CNetMsgMaker msgMaker(pto->GetSendVersion()); if (!state.m_chain_sync.m_protect && IsOutboundDisconnectionCandidate(pto) && 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() : ""); pto->fDisconnect = true; } else { 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() : "", state.m_chain_sync.m_work_header->GetBlockHash() .ToString()); 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; // 2 minutes constexpr int64_t HEADERS_RESPONSE_TIME = 120; // 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 PeerLogicValidation::EvictExtraOutboundPeers(int64_t time_in_seconds) { // Check whether we have too many outbound peers int extra_peers = connman->GetExtraOutboundCount(); if (extra_peers <= 0) { return; } // 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::max(); LOCK(cs_main); connman->ForEachNode([&](CNode *pnode) { AssertLockHeld(cs_main); // Ignore non-outbound peers, or nodes marked for disconnect already if (!IsOutboundDisconnectionCandidate(pnode) || pnode->fDisconnect) { return; } CNodeState *state = State(pnode->GetId()); if (state == nullptr) { // shouldn't be possible, but just in case return; } // Don't evict our protected peers if (state->m_chain_sync.m_protect) { 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) { return; } bool disconnected = connman->ForNode(worst_peer, [&](CNode *pnode) { 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. connman->SetTryNewOutboundPeer(false); } } void PeerLogicValidation::CheckForStaleTipAndEvictPeers( const Consensus::Params &consensusParams) { if (connman == nullptr) { return; } int64_t time_in_seconds = GetTime(); EvictExtraOutboundPeers(time_in_seconds); if (time_in_seconds <= m_stale_tip_check_time) { return; } LOCK(cs_main); // Check whether our tip is stale, and if so, allow using an extra outbound // peer. if (TipMayBeStale(consensusParams)) { 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); connman->SetTryNewOutboundPeer(true); } else if (connman->GetTryNewOutboundPeer()) { connman->SetTryNewOutboundPeer(false); } m_stale_tip_check_time = time_in_seconds + STALE_CHECK_INTERVAL; } namespace { class CompareInvMempoolOrder { CTxMemPool *mp; public: explicit CompareInvMempoolOrder(CTxMemPool *_mempool) { mp = _mempool; } bool operator()(std::set::iterator a, std::set::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); } }; } bool PeerLogicValidation::SendMessages(const Config &config, CNode *pto, std::atomic &interruptMsgProc) { const Consensus::Params &consensusParams = config.GetChainParams().GetConsensus(); // 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->GetSendVersion()); // // Message: ping // bool pingSend = false; if (pto->fPingQueued) { // RPC ping request by user pingSend = true; } if (pto->nPingNonceSent == 0 && pto->nPingUsecStart + PING_INTERVAL * 1000000 < GetTimeMicros()) { // Ping automatically sent as a latency probe & keepalive. pingSend = true; } if (pingSend) { uint64_t nonce = 0; while (nonce == 0) { GetRandBytes((uint8_t *)&nonce, sizeof(nonce)); } pto->fPingQueued = false; pto->nPingUsecStart = GetTimeMicros(); if (pto->nVersion > BIP0031_VERSION) { pto->nPingNonceSent = nonce; 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; connman->PushMessage(pto, msgMaker.Make(NetMsgType::PING)); } } // Acquire cs_main for IsInitialBlockDownload() and CNodeState() TRY_LOCK(cs_main, lockMain); if (!lockMain) { return true; } if (SendRejectsAndCheckIfBanned(pto, connman)) { return true; } CNodeState &state = *State(pto->GetId()); // Address refresh broadcast int64_t nNow = GetTimeMicros(); if (!IsInitialBlockDownload() && pto->nNextLocalAddrSend < nNow) { AdvertiseLocal(pto); pto->nNextLocalAddrSend = PoissonNextSend(nNow, AVG_LOCAL_ADDRESS_BROADCAST_INTERVAL); } // // Message: addr // if (pto->nNextAddrSend < nNow) { pto->nNextAddrSend = PoissonNextSend(nNow, AVG_ADDRESS_BROADCAST_INTERVAL); std::vector vAddr; vAddr.reserve(pto->vAddrToSend.size()); for (const CAddress &addr : pto->vAddrToSend) { if (!pto->addrKnown.contains(addr.GetKey())) { pto->addrKnown.insert(addr.GetKey()); vAddr.push_back(addr); // receiver rejects addr messages larger than 1000 if (vAddr.size() >= 1000) { connman->PushMessage( pto, msgMaker.Make(NetMsgType::ADDR, vAddr)); vAddr.clear(); } } } pto->vAddrToSend.clear(); if (!vAddr.empty()) { connman->PushMessage(pto, msgMaker.Make(NetMsgType::ADDR, 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(); } // Download if this is a nice peer, or we have no nice peers and this one // might do. bool fFetch = state.fPreferredDownload || (nPreferredDownload == 0 && !pto->fClient && !pto->fOneShot); 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 = GetTimeMicros() + 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); connman->PushMessage( pto, msgMaker.Make(NetMsgType::GETHEADERS, chainActive.GetLocator(pindexStart), uint256())); } } // Resend wallet transactions that haven't gotten in a block yet // Except during reindex, importing and IBD, when old wallet transactions // become unconfirmed and spams other nodes. if (!fReindex && !fImporting && !IsInitialBlockDownload()) { GetMainSignals().Broadcast(nTimeBestReceived, connman); } // // 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 vHeaders; bool fRevertToInv = ((!state.fPreferHeaders && (!state.fPreferHeaderAndIDs || pto->vBlockHashesToAnnounce.size() > 1)) || pto->vBlockHashesToAnnounce.size() > MAX_BLOCKS_TO_ANNOUNCE); // last header queued for delivery const CBlockIndex *pBestIndex = nullptr; // ensure pindexBestKnownBlock is up-to-date ProcessBlockAvailability(pto->GetId()); 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 an headers that // aren't on chainActive, give up. for (const uint256 &hash : pto->vBlockHashesToAnnounce) { BlockMap::iterator mi = mapBlockIndex.find(hash); assert(mi != mapBlockIndex.end()); const CBlockIndex *pindex = mi->second; 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)) { // Keep looking for the first new block. continue; } 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 = 0; bool fGotBlockFromCache = false; { LOCK(cs_most_recent_block); if (most_recent_block_hash == pBestIndex->GetBlockHash()) { CBlockHeaderAndShortTxIDs cmpctblock( *most_recent_block); connman->PushMessage( pto, msgMaker.Make(nSendFlags, NetMsgType::CMPCTBLOCK, cmpctblock)); fGotBlockFromCache = true; } } if (!fGotBlockFromCache) { CBlock block; bool ret = ReadBlockFromDisk(block, pBestIndex, config); assert(ret); CBlockHeaderAndShortTxIDs cmpctblock(block); 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()); } 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(); BlockMap::iterator mi = mapBlockIndex.find(hashToAnnounce); assert(mi != mapBlockIndex.end()); const CBlockIndex *pindex = mi->second; // 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->PushInventory(CInv(MSG_BLOCK, hashToAnnounce)); LogPrint(BCLog::NET, "%s: sending inv peer=%d hash=%s\n", __func__, pto->GetId(), hashToAnnounce.ToString()); } } } pto->vBlockHashesToAnnounce.clear(); } // // Message: inventory // std::vector vInv; { LOCK(pto->cs_inventory); vInv.reserve(std::max(pto->vInventoryBlockToSend.size(), INVENTORY_BROADCAST_MAX_PER_MB * config.GetMaxBlockSize() / 1000000)); // Add blocks for (const uint256 &hash : pto->vInventoryBlockToSend) { vInv.push_back(CInv(MSG_BLOCK, hash)); if (vInv.size() == MAX_INV_SZ) { connman->PushMessage(pto, msgMaker.Make(NetMsgType::INV, vInv)); vInv.clear(); } } pto->vInventoryBlockToSend.clear(); // Check whether periodic sends should happen bool fSendTrickle = pto->fWhitelisted; if (pto->nNextInvSend < nNow) { fSendTrickle = true; // Use half the delay for outbound peers, as there is less privacy // concern for them. pto->nNextInvSend = PoissonNextSend( nNow, INVENTORY_BROADCAST_INTERVAL >> !pto->fInbound); } // Time to send but the peer has requested we not relay transactions. if (fSendTrickle) { LOCK(pto->cs_filter); if (!pto->fRelayTxes) { pto->setInventoryTxToSend.clear(); } } // Respond to BIP35 mempool requests if (fSendTrickle && pto->fSendMempool) { auto vtxinfo = g_mempool.infoAll(); pto->fSendMempool = false; Amount filterrate = Amount::zero(); { LOCK(pto->cs_feeFilter); filterrate = pto->minFeeFilter; } LOCK(pto->cs_filter); for (const auto &txinfo : vtxinfo) { const uint256 &txid = txinfo.tx->GetId(); CInv inv(MSG_TX, txid); pto->setInventoryTxToSend.erase(txid); if (filterrate != Amount::zero() && txinfo.feeRate.GetFeePerK() < filterrate) { continue; } if (pto->pfilter && !pto->pfilter->IsRelevantAndUpdate(*txinfo.tx)) { continue; } pto->filterInventoryKnown.insert(txid); vInv.push_back(inv); if (vInv.size() == MAX_INV_SZ) { connman->PushMessage(pto, msgMaker.Make(NetMsgType::INV, vInv)); vInv.clear(); } } pto->timeLastMempoolReq = GetTime(); } // Determine transactions to relay if (fSendTrickle) { // Produce a vector with all candidates for sending std::vector::iterator> vInvTx; vInvTx.reserve(pto->setInventoryTxToSend.size()); for (std::set::iterator it = pto->setInventoryTxToSend.begin(); it != pto->setInventoryTxToSend.end(); it++) { vInvTx.push_back(it); } Amount filterrate = Amount::zero(); { LOCK(pto->cs_feeFilter); filterrate = pto->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(&g_mempool); 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->cs_filter); while (!vInvTx.empty() && nRelayedTransactions < INVENTORY_BROADCAST_MAX_PER_MB * config.GetMaxBlockSize() / 1000000) { // Fetch the top element from the heap std::pop_heap(vInvTx.begin(), vInvTx.end(), compareInvMempoolOrder); std::set::iterator it = vInvTx.back(); vInvTx.pop_back(); uint256 hash = *it; // Remove it from the to-be-sent set pto->setInventoryTxToSend.erase(it); // Check if not in the filter already if (pto->filterInventoryKnown.contains(hash)) { continue; } // Not in the mempool anymore? don't bother sending it. auto txinfo = g_mempool.info(hash); if (!txinfo.tx) { continue; } if (filterrate != Amount::zero() && txinfo.feeRate.GetFeePerK() < filterrate) { continue; } if (pto->pfilter && !pto->pfilter->IsRelevantAndUpdate(*txinfo.tx)) { continue; } // Send vInv.push_back(CInv(MSG_TX, hash)); nRelayedTransactions++; { // Expire old relay messages while (!vRelayExpiration.empty() && vRelayExpiration.front().first < nNow) { mapRelay.erase(vRelayExpiration.front().second); vRelayExpiration.pop_front(); } auto ret = mapRelay.insert( std::make_pair(hash, std::move(txinfo.tx))); if (ret.second) { vRelayExpiration.push_back(std::make_pair( nNow + 15 * 60 * 1000000, ret.first)); } } if (vInv.size() == MAX_INV_SZ) { connman->PushMessage(pto, msgMaker.Make(NetMsgType::INV, vInv)); vInv.clear(); } pto->filterInventoryKnown.insert(hash); } } } if (!vInv.empty()) { connman->PushMessage(pto, msgMaker.Make(NetMsgType::INV, vInv)); } // Detect whether we're stalling nNow = GetTimeMicros(); if (state.nStallingSince && state.nStallingSince < nNow - 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 (nNow > 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::max()) { // Detect whether this is a stalling initial-headers-sync peer if (pindexBestHeader->GetBlockTime() <= GetAdjustedTime() - 24 * 60 * 60) { if (nNow > state.nHeadersSyncTimeout && nSyncStarted == 1 && (nPreferredDownload - state.fPreferredDownload >= 1)) { // Disconnect a (non-whitelisted) peer 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->fWhitelisted) { LogPrintf("Timeout downloading headers from peer=%d, " "disconnecting\n", pto->GetId()); pto->fDisconnect = true; return true; } else { LogPrintf("Timeout downloading headers from whitelisted " "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::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 vGetData; if (!pto->fClient && (fFetch || !IsInitialBlockDownload()) && state.nBlocksInFlight < MAX_BLOCKS_IN_TRANSIT_PER_PEER) { std::vector vToDownload; NodeId staller = -1; FindNextBlocksToDownload(pto->GetId(), MAX_BLOCKS_IN_TRANSIT_PER_PEER - state.nBlocksInFlight, vToDownload, staller, consensusParams); for (const CBlockIndex *pindex : vToDownload) { vGetData.push_back(CInv(MSG_BLOCK, pindex->GetBlockHash())); MarkBlockAsInFlight(config, pto->GetId(), pindex->GetBlockHash(), consensusParams, 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 = nNow; LogPrint(BCLog::NET, "Stall started peer=%d\n", staller); } } } // // Message: getdata (non-blocks) // while (!pto->mapAskFor.empty() && (*pto->mapAskFor.begin()).first <= nNow) { const CInv &inv = (*pto->mapAskFor.begin()).second; if (!AlreadyHave(inv)) { LogPrint(BCLog::NET, "Requesting %s peer=%d\n", inv.ToString(), pto->GetId()); vGetData.push_back(inv); if (vGetData.size() >= 1000) { connman->PushMessage( pto, msgMaker.Make(NetMsgType::GETDATA, vGetData)); vGetData.clear(); } } else { // If we're not going to ask, don't expect a response. pto->setAskFor.erase(inv.hash); } pto->mapAskFor.erase(pto->mapAskFor.begin()); } if (!vGetData.empty()) { connman->PushMessage(pto, msgMaker.Make(NetMsgType::GETDATA, vGetData)); } // // Message: feefilter // // We don't want white listed peers to filter txs to us if we have // -whitelistforcerelay if (pto->nVersion >= FEEFILTER_VERSION && gArgs.GetBoolArg("-feefilter", DEFAULT_FEEFILTER) && !(pto->fWhitelisted && gArgs.GetBoolArg("-whitelistforcerelay", DEFAULT_WHITELISTFORCERELAY))) { Amount currentFilter = g_mempool .GetMinFee( gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000) .GetFeePerK(); int64_t timeNow = GetTimeMicros(); if (timeNow > pto->nextSendTimeFeeFilter) { static CFeeRate default_feerate = CFeeRate(DEFAULT_MIN_RELAY_TX_FEE_PER_KB); static FeeFilterRounder filterRounder(default_feerate); Amount filterToSend = filterRounder.round(currentFilter); // If we don't allow free transactions, then we always have a fee // filter of at least minRelayTxFee if (gArgs.GetArg("-limitfreerelay", DEFAULT_LIMITFREERELAY) <= 0) { filterToSend = std::max(filterToSend, config.GetMinFeePerKB().GetFeePerK()); } if (filterToSend != pto->lastSentFeeFilter) { connman->PushMessage( pto, msgMaker.Make(NetMsgType::FEEFILTER, filterToSend)); pto->lastSentFeeFilter = filterToSend; } pto->nextSendTimeFeeFilter = PoissonNextSend(timeNow, 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 (timeNow + MAX_FEEFILTER_CHANGE_DELAY * 1000000 < pto->nextSendTimeFeeFilter && (currentFilter < 3 * pto->lastSentFeeFilter / 4 || currentFilter > 4 * pto->lastSentFeeFilter / 3)) { pto->nextSendTimeFeeFilter = timeNow + GetRandInt(MAX_FEEFILTER_CHANGE_DELAY) * 1000000; } } return true; } class CNetProcessingCleanup { public: CNetProcessingCleanup() {} ~CNetProcessingCleanup() { // orphan transactions mapOrphanTransactions.clear(); mapOrphanTransactionsByPrev.clear(); } } instance_of_cnetprocessingcleanup; diff --git a/test/functional/p2p-fingerprint.py b/test/functional/p2p-fingerprint.py new file mode 100755 index 0000000000..81961527cb --- /dev/null +++ b/test/functional/p2p-fingerprint.py @@ -0,0 +1,166 @@ +#!/usr/bin/env python3 +# Copyright (c) 2017 The Bitcoin Core developers +# Distributed under the MIT software license, see the accompanying +# file COPYING or http://www.opensource.org/licenses/mit-license.php. +"""Test various fingerprinting protections. + +If an stale block more than a month old or its header are requested by a peer, +the node should pretend that it does not have it to avoid fingerprinting. +""" + +import time + +from test_framework.blocktools import (create_block, create_coinbase) +from test_framework.mininode import ( + CInv, + NetworkThread, + NodeConn, + NodeConnCB, + msg_headers, + msg_block, + msg_getdata, + msg_getheaders, + wait_until, +) +from test_framework.test_framework import BitcoinTestFramework +from test_framework.util import ( + assert_equal, + p2p_port, +) + + +class P2PFingerprintTest(BitcoinTestFramework): + def set_test_params(self): + self.setup_clean_chain = True + self.num_nodes = 1 + + # Build a chain of blocks on top of given one + def build_chain(self, nblocks, prev_hash, prev_height, prev_median_time): + blocks = [] + for _ in range(nblocks): + coinbase = create_coinbase(prev_height + 1) + block_time = prev_median_time + 1 + block = create_block(int(prev_hash, 16), coinbase, block_time) + block.solve() + + blocks.append(block) + prev_hash = block.hash + prev_height += 1 + prev_median_time = block_time + return blocks + + # Send a getdata request for a given block hash + def send_block_request(self, block_hash, node): + msg = msg_getdata() + # 2 == "Block" + msg.inv.append(CInv(2, block_hash)) + node.send_message(msg) + + # Send a getheaders request for a given single block hash + def send_header_request(self, block_hash, node): + msg = msg_getheaders() + msg.hashstop = block_hash + node.send_message(msg) + + # Check whether last block received from node has a given hash + def last_block_equals(self, expected_hash, node): + block_msg = node.last_message.get("block") + return block_msg and block_msg.block.rehash() == expected_hash + + # Check whether last block header received from node has a given hash + def last_header_equals(self, expected_hash, node): + headers_msg = node.last_message.get("headers") + return (headers_msg and + headers_msg.headers and + headers_msg.headers[0].rehash() == expected_hash) + + # Checks that stale blocks timestamped more than a month ago are not served + # by the node while recent stale blocks and old active chain blocks are. + # This does not currently test that stale blocks timestamped within the + # last month but that have over a month's worth of work are also withheld. + def run_test(self): + node0 = NodeConnCB() + + connections = [] + connections.append( + NodeConn('127.0.0.1', p2p_port(0), self.nodes[0], node0)) + node0.add_connection(connections[0]) + + NetworkThread().start() + node0.wait_for_verack() + + # Set node time to 60 days ago + self.nodes[0].setmocktime(int(time.time()) - 60 * 24 * 60 * 60) + + # Generating a chain of 10 blocks + block_hashes = self.nodes[0].generate(nblocks=10) + + # Create longer chain starting 2 blocks before current tip + height = len(block_hashes) - 2 + block_hash = block_hashes[height - 1] + block_time = self.nodes[0].getblockheader(block_hash)["mediantime"] + 1 + new_blocks = self.build_chain(5, block_hash, height, block_time) + + # Force reorg to a longer chain + node0.send_message(msg_headers(new_blocks)) + node0.wait_for_getdata() + for block in new_blocks: + node0.send_and_ping(msg_block(block)) + + # Check that reorg succeeded + assert_equal(self.nodes[0].getblockcount(), 13) + + stale_hash = int(block_hashes[-1], 16) + + # Check that getdata request for stale block succeeds + self.send_block_request(stale_hash, node0) + + def test_function(): return self.last_block_equals(stale_hash, node0) + wait_until(test_function, timeout=3) + + # Check that getheader request for stale block header succeeds + self.send_header_request(stale_hash, node0) + + def test_function(): return self.last_header_equals(stale_hash, node0) + wait_until(test_function, timeout=3) + + # Longest chain is extended so stale is much older than chain tip + self.nodes[0].setmocktime(0) + tip = self.nodes[0].generate(nblocks=1)[0] + assert_equal(self.nodes[0].getblockcount(), 14) + + # Send getdata & getheaders to refresh last received getheader message + block_hash = int(tip, 16) + self.send_block_request(block_hash, node0) + self.send_header_request(block_hash, node0) + node0.sync_with_ping() + + # Request for very old stale block should now fail + self.send_block_request(stale_hash, node0) + time.sleep(3) + assert not self.last_block_equals(stale_hash, node0) + + # Request for very old stale block header should now fail + self.send_header_request(stale_hash, node0) + time.sleep(3) + assert not self.last_header_equals(stale_hash, node0) + + # Verify we can fetch very old blocks and headers on the active chain + block_hash = int(block_hashes[2], 16) + self.send_block_request(block_hash, node0) + self.send_header_request(block_hash, node0) + node0.sync_with_ping() + + self.send_block_request(block_hash, node0) + + def test_function(): return self.last_block_equals(block_hash, node0) + wait_until(test_function, timeout=3) + + self.send_header_request(block_hash, node0) + + def test_function(): return self.last_header_equals(block_hash, node0) + wait_until(test_function, timeout=3) + + +if __name__ == '__main__': + P2PFingerprintTest().main() diff --git a/test/functional/test_framework/mininode.py b/test/functional/test_framework/mininode.py index 069559cb54..42ae39b1f2 100755 --- a/test/functional/test_framework/mininode.py +++ b/test/functional/test_framework/mininode.py @@ -1,1610 +1,1610 @@ #!/usr/bin/env python3 # Copyright (c) 2010 ArtForz -- public domain half-a-node # Copyright (c) 2012 Jeff Garzik # Copyright (c) 2010-2016 The Bitcoin Core developers # Distributed under the MIT software license, see the accompanying # file COPYING or http://www.opensource.org/licenses/mit-license.php. """Bitcoin P2P network half-a-node. This python code was modified from ArtForz' public domain half-a-node, as found in the mini-node branch of http://github.com/jgarzik/pynode. NodeConn: an object which manages p2p connectivity to a bitcoin node NodeConnCB: a base class that describes the interface for receiving callbacks with network messages from a NodeConn CBlock, CTransaction, CBlockHeader, CTxIn, CTxOut, etc....: data structures that should map to corresponding structures in bitcoin/primitives msg_block, msg_tx, msg_headers, etc.: data structures that represent network messages ser_*, deser_*: functions that handle serialization/deserialization """ import asyncore from codecs import encode from collections import defaultdict import copy import hashlib from io import BytesIO import logging import random import socket import struct import sys import time from threading import RLock, Thread from test_framework.siphash import siphash256 from test_framework.cdefs import MAX_BLOCK_SIGOPS_PER_MB from test_framework.util import hex_str_to_bytes, bytes_to_hex_str, wait_until MIN_VERSION_SUPPORTED = 60001 MY_VERSION = 70014 # past bip-31 for ping/pong MY_SUBVERSION = b"/python-mininode-tester:0.0.3/" # from version 70001 onwards, fRelay should be appended to version messages (BIP37) MY_RELAY = 1 MAX_INV_SZ = 50000 COIN = 100000000 # 1 btc in satoshis NODE_NETWORK = (1 << 0) # NODE_GETUTXO = (1 << 1) # NODE_BLOOM = (1 << 2) NODE_WITNESS = (1 << 3) NODE_XTHIN = (1 << 4) NODE_BITCOIN_CASH = (1 << 5) # Howmuch data will be read from the network at once READ_BUFFER_SIZE = 8192 logger = logging.getLogger("TestFramework.mininode") # Keep our own socket map for asyncore, so that we can track disconnects # ourselves (to workaround an issue with closing an asyncore socket when # using select) mininode_socket_map = dict() # One lock for synchronizing all data access between the networking thread (see # NetworkThread below) and the thread running the test logic. For simplicity, # NodeConn acquires this lock whenever delivering a message to a NodeConnCB, # and whenever adding anything to the send buffer (in send_message()). This # lock should be acquired in the thread running the test logic to synchronize # access to any data shared with the NodeConnCB or NodeConn. mininode_lock = RLock() # Serialization/deserialization tools def sha256(s): return hashlib.new('sha256', s).digest() def ripemd160(s): return hashlib.new('ripemd160', s).digest() def hash256(s): return sha256(sha256(s)) def ser_compact_size(l): r = b"" if l < 253: r = struct.pack("B", l) elif l < 0x10000: r = struct.pack(">= 32 return rs def uint256_from_str(s): r = 0 t = struct.unpack("> 24) & 0xFF v = (c & 0xFFFFFF) << (8 * (nbytes - 3)) return v def deser_vector(f, c): nit = deser_compact_size(f) r = [] for i in range(nit): t = c() t.deserialize(f) r.append(t) return r # ser_function_name: Allow for an alternate serialization function on the # entries in the vector. def ser_vector(l, ser_function_name=None): r = ser_compact_size(len(l)) for i in l: if ser_function_name: r += getattr(i, ser_function_name)() else: r += i.serialize() return r def deser_uint256_vector(f): nit = deser_compact_size(f) r = [] for i in range(nit): t = deser_uint256(f) r.append(t) return r def ser_uint256_vector(l): r = ser_compact_size(len(l)) for i in l: r += ser_uint256(i) return r def deser_string_vector(f): nit = deser_compact_size(f) r = [] for i in range(nit): t = deser_string(f) r.append(t) return r def ser_string_vector(l): r = ser_compact_size(len(l)) for sv in l: r += ser_string(sv) return r def deser_int_vector(f): nit = deser_compact_size(f) r = [] for i in range(nit): t = struct.unpack("H", f.read(2))[0] def serialize(self): r = b"" r += struct.pack("H", self.port) return r def __repr__(self): return "CAddress(nServices=%i ip=%s port=%i)" % (self.nServices, self.ip, self.port) class CInv(): typemap = { 0: "Error", 1: "TX", 2: "Block", 4: "CompactBlock" } def __init__(self, t=0, h=0): self.type = t self.hash = h def deserialize(self, f): self.type = struct.unpack(" 21000000 * COIN: return False return True def __repr__(self): return "CTransaction(nVersion=%i vin=%s vout=%s nLockTime=%i)" \ % (self.nVersion, repr(self.vin), repr(self.vout), self.nLockTime) class CBlockHeader(): def __init__(self, header=None): if header is None: self.set_null() else: self.nVersion = header.nVersion self.hashPrevBlock = header.hashPrevBlock self.hashMerkleRoot = header.hashMerkleRoot self.nTime = header.nTime self.nBits = header.nBits self.nNonce = header.nNonce self.sha256 = header.sha256 self.hash = header.hash self.calc_sha256() def set_null(self): self.nVersion = 1 self.hashPrevBlock = 0 self.hashMerkleRoot = 0 self.nTime = 0 self.nBits = 0 self.nNonce = 0 self.sha256 = None self.hash = None def deserialize(self, f): self.nVersion = struct.unpack(" 1: newhashes = [] for i in range(0, len(hashes), 2): i2 = min(i + 1, len(hashes) - 1) newhashes.append(hash256(hashes[i] + hashes[i2])) hashes = newhashes return uint256_from_str(hashes[0]) def calc_merkle_root(self): hashes = [] for tx in self.vtx: tx.calc_sha256() hashes.append(ser_uint256(tx.sha256)) return self.get_merkle_root(hashes) def is_valid(self): self.calc_sha256() target = uint256_from_compact(self.nBits) if self.sha256 > target: return False for tx in self.vtx: if not tx.is_valid(): return False if self.calc_merkle_root() != self.hashMerkleRoot: return False return True def solve(self): self.rehash() target = uint256_from_compact(self.nBits) while self.sha256 > target: self.nNonce += 1 self.rehash() def __repr__(self): return "CBlock(nVersion=%i hashPrevBlock=%064x hashMerkleRoot=%064x nTime=%s nBits=%08x nNonce=%08x vtx=%s)" \ % (self.nVersion, self.hashPrevBlock, self.hashMerkleRoot, time.ctime(self.nTime), self.nBits, self.nNonce, repr(self.vtx)) class PrefilledTransaction(): def __init__(self, index=0, tx=None): self.index = index self.tx = tx def deserialize(self, f): self.index = deser_compact_size(f) self.tx = CTransaction() self.tx.deserialize(f) def serialize(self): r = b"" r += ser_compact_size(self.index) r += self.tx.serialize() return r def __repr__(self): return "PrefilledTransaction(index=%d, tx=%s)" % (self.index, repr(self.tx)) # This is what we send on the wire, in a cmpctblock message. class P2PHeaderAndShortIDs(): def __init__(self): self.header = CBlockHeader() self.nonce = 0 self.shortids_length = 0 self.shortids = [] self.prefilled_txn_length = 0 self.prefilled_txn = [] def deserialize(self, f): self.header.deserialize(f) self.nonce = struct.unpack("= 106: self.addrFrom = CAddress() self.addrFrom.deserialize(f) self.nNonce = struct.unpack("= 209: self.nStartingHeight = struct.unpack("= 70001: # Relay field is optional for version 70001 onwards try: self.nRelay = struct.unpack(" class msg_headers(): command = b"headers" - def __init__(self): - self.headers = [] + def __init__(self, headers=None): + self.headers = headers if headers is not None else [] def deserialize(self, f): # comment in bitcoind indicates these should be deserialized as blocks blocks = deser_vector(f, CBlock) for x in blocks: self.headers.append(CBlockHeader(x)) def serialize(self): blocks = [CBlock(x) for x in self.headers] return ser_vector(blocks) def __repr__(self): return "msg_headers(headers=%s)" % repr(self.headers) class msg_reject(): command = b"reject" REJECT_MALFORMED = 1 def __init__(self): self.message = b"" self.code = 0 self.reason = b"" self.data = 0 def deserialize(self, f): self.message = deser_string(f) self.code = struct.unpack("= MIN_VERSION_SUPPORTED, "Version {} received. Test framework only supports versions greater than {}".format( message.nVersion, MIN_VERSION_SUPPORTED) conn.send_message(msg_verack()) conn.nServices = message.nServices # Connection helper methods def add_connection(self, conn): self.connection = conn def wait_for_disconnect(self, timeout=60): def test_function(): return not self.connected wait_until(test_function, timeout=timeout, lock=mininode_lock) # Message receiving helper methods def wait_for_block(self, blockhash, timeout=60): def test_function(): return self.last_message.get( "block") and self.last_message["block"].block.rehash() == blockhash wait_until(test_function, timeout=timeout, lock=mininode_lock) def wait_for_getdata(self, timeout=60): def test_function(): return self.last_message.get("getdata") wait_until(test_function, timeout=timeout, lock=mininode_lock) def wait_for_getheaders(self, timeout=60): def test_function(): return self.last_message.get("getheaders") wait_until(test_function, timeout=timeout, lock=mininode_lock) def wait_for_inv(self, expected_inv, timeout=60): """Waits for an INV message and checks that the first inv object in the message was as expected.""" if len(expected_inv) > 1: raise NotImplementedError( "wait_for_inv() will only verify the first inv object") def test_function(): return self.last_message.get("inv") and \ self.last_message["inv"].inv[0].type == expected_inv[0].type and \ self.last_message["inv"].inv[0].hash == expected_inv[0].hash wait_until(test_function, timeout=timeout, lock=mininode_lock) def wait_for_verack(self, timeout=60): def test_function(): return self.message_count["verack"] wait_until(test_function, timeout=timeout, lock=mininode_lock) # Message sending helper functions def send_message(self, message): if self.connection: self.connection.send_message(message) else: logger.error("Cannot send message. No connection to node!") def send_and_ping(self, message): self.send_message(message) self.sync_with_ping() # Sync up with the node def sync_with_ping(self, timeout=60): self.send_message(msg_ping(nonce=self.ping_counter)) def test_function(): if not self.last_message.get("pong"): return False return self.last_message["pong"].nonce == self.ping_counter wait_until(test_function, timeout=timeout, lock=mininode_lock) self.ping_counter += 1 class NodeConn(asyncore.dispatcher): """The actual NodeConn class This class provides an interface for a p2p connection to a specified node.""" messagemap = { b"version": msg_version, b"verack": msg_verack, b"addr": msg_addr, b"inv": msg_inv, b"getdata": msg_getdata, b"getblocks": msg_getblocks, b"tx": msg_tx, b"block": msg_block, b"getaddr": msg_getaddr, b"ping": msg_ping, b"pong": msg_pong, b"headers": msg_headers, b"getheaders": msg_getheaders, b"reject": msg_reject, b"mempool": msg_mempool, b"feefilter": msg_feefilter, b"sendheaders": msg_sendheaders, b"sendcmpct": msg_sendcmpct, b"cmpctblock": msg_cmpctblock, b"getblocktxn": msg_getblocktxn, b"blocktxn": msg_blocktxn } MAGIC_BYTES = { "mainnet": b"\xe3\xe1\xf3\xe8", "testnet3": b"\xf4\xe5\xf3\xf4", "regtest": b"\xda\xb5\xbf\xfa", } def __init__(self, dstaddr, dstport, rpc, callback, net="regtest", services=NODE_NETWORK, send_version=True): asyncore.dispatcher.__init__(self, map=mininode_socket_map) self.dstaddr = dstaddr self.dstport = dstport self.create_socket(socket.AF_INET, socket.SOCK_STREAM) self.socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1) self.sendbuf = b"" self.recvbuf = b"" self.ver_send = 209 self.ver_recv = 209 self.last_sent = 0 self.state = "connecting" self.network = net self.cb = callback self.disconnect = False self.nServices = 0 if send_version: # stuff version msg into sendbuf vt = msg_version() vt.nServices = services vt.addrTo.ip = self.dstaddr vt.addrTo.port = self.dstport vt.addrFrom.ip = "0.0.0.0" vt.addrFrom.port = 0 self.send_message(vt, True) logger.info('Connecting to Bitcoin Node: %s:%d' % (self.dstaddr, self.dstport)) try: self.connect((dstaddr, dstport)) except: self.handle_close() self.rpc = rpc def handle_connect(self): if self.state != "connected": logger.debug("Connected & Listening: %s:%d" % (self.dstaddr, self.dstport)) self.state = "connected" self.cb.on_open(self) def handle_close(self): logger.debug("Closing connection to: %s:%d" % (self.dstaddr, self.dstport)) self.state = "closed" self.recvbuf = b"" self.sendbuf = b"" try: self.close() except: pass self.cb.on_close(self) def handle_read(self): with mininode_lock: t = self.recv(READ_BUFFER_SIZE) if len(t) > 0: self.recvbuf += t while True: msg = self.got_data() if msg == None: break self.got_message(msg) def readable(self): return True def writable(self): with mininode_lock: pre_connection = self.state == "connecting" length = len(self.sendbuf) return (length > 0 or pre_connection) def handle_write(self): with mininode_lock: # asyncore does not expose socket connection, only the first read/write # event, thus we must check connection manually here to know when we # actually connect if self.state == "connecting": self.handle_connect() if not self.writable(): return try: sent = self.send(self.sendbuf) except: self.handle_close() return self.sendbuf = self.sendbuf[sent:] def got_data(self): try: with mininode_lock: if len(self.recvbuf) < 4: return None if self.recvbuf[:4] != self.MAGIC_BYTES[self.network]: raise ValueError("got garbage %s" % repr(self.recvbuf)) if len(self.recvbuf) < 4 + 12 + 4 + 4: return command = self.recvbuf[4:4+12].split(b"\x00", 1)[0] msglen = struct.unpack(" 500: log_message += "... (msg truncated)" logger.debug(log_message) def disconnect_node(self): self.disconnect = True class NetworkThread(Thread): def run(self): while mininode_socket_map: # We check for whether to disconnect outside of the asyncore # loop to workaround the behavior of asyncore when using # select disconnected = [] for fd, obj in mininode_socket_map.items(): if obj.disconnect: disconnected.append(obj) [obj.handle_close() for obj in disconnected] asyncore.loop(0.1, use_poll=True, map=mininode_socket_map, count=1) logger.debug("Network thread closing") diff --git a/test/functional/timing.json b/test/functional/timing.json index d411229ce8..6a24e11b25 100644 --- a/test/functional/timing.json +++ b/test/functional/timing.json @@ -1,362 +1,366 @@ [ { "name": "abandonconflict.py", - "time": 15 + "time": 11 }, { "name": "abc-checkdatasig-activation.py", - "time": 22 + "time": 3 }, { "name": "abc-cmdline.py", - "time": 10 + "time": 7 }, { "name": "abc-finalize-block.py", - "time": 7 + "time": 5 }, { "name": "abc-high_priority_transaction.py", - "time": 20 + "time": 6 }, { "name": "abc-magnetic-anomaly-activation.py", - "time": 6 + "time": 5 }, { "name": "abc-magnetic-anomaly-mining.py", - "time": 29 + "time": 3 }, { "name": "abc-mempool-accept-txn.py", - "time": 13 + "time": 3 }, { "name": "abc-p2p-compactblocks.py", - "time": 411 + "time": 253 }, { "name": "abc-p2p-fullblocktest.py", - "time": 79 + "time": 31 }, { "name": "abc-parkedchain.py", - "time": 13 + "time": 4 }, { "name": "abc-replay-protection.py", - "time": 4 + "time": 3 }, { "name": "abc-rpc.py", "time": 2 }, { "name": "abc-sync-chain.py", - "time": 3 + "time": 2 }, { "name": "abc-transaction-ordering.py", - "time": 6 + "time": 5 }, { "name": "assumevalid.py", - "time": 12 + "time": 8 }, { "name": "bip65-cltv-p2p.py", - "time": 5 + "time": 4 }, { "name": "bip68-112-113-p2p.py", - "time": 39 + "time": 14 }, { "name": "bip68-sequence.py", - "time": 64 + "time": 12 }, { "name": "bipdersig-p2p.py", - "time": 5 + "time": 3 }, { "name": "bitcoin_cli.py", - "time": 13 + "time": 2 }, { "name": "blockchain.py", - "time": 40 + "time": 10 }, { "name": "dbcrash.py", - "time": 1320 + "time": 537 }, { "name": "decodescript.py", - "time": 3 + "time": 2 }, { "name": "disablewallet.py", "time": 2 }, { "name": "disconnect_ban.py", - "time": 20 + "time": 7 }, { "name": "example_test.py", - "time": 3 + "time": 2 }, { "name": "fundrawtransaction.py", - "time": 47 + "time": 31 }, { "name": "getblocktemplate_longpoll.py", - "time": 68 + "time": 67 }, { "name": "getchaintips.py", - "time": 28 + "time": 3 }, { "name": "httpbasics.py", - "time": 4 + "time": 2 }, { "name": "import-rescan.py", - "time": 16 + "time": 3 }, { "name": "importmulti.py", - "time": 26 + "time": 5 }, { "name": "importprunedfunds.py", - "time": 4 + "time": 2 }, { "name": "invalidateblock.py", - "time": 8 + "time": 7 }, { "name": "invalidblockrequest.py", - "time": 4 + "time": 3 }, { "name": "invalidtxrequest.py", "time": 3 }, { "name": "keypool-topup.py", - "time": 32 + "time": 8 }, { "name": "keypool.py", - "time": 37 + "time": 6 }, { "name": "listsinceblock.py", - "time": 5 + "time": 3 }, { "name": "listtransactions.py", "time": 9 }, { "name": "maxuploadtarget.py", - "time": 26 + "time": 21 }, { "name": "mempool_limit.py", - "time": 10 + "time": 4 }, { "name": "mempool_packages.py", - "time": 26 + "time": 9 }, { "name": "mempool_persist.py", - "time": 46 + "time": 17 }, { "name": "mempool_reorg.py", - "time": 8 + "time": 6 }, { "name": "mempool_resurrect_test.py", - "time": 4 + "time": 2 }, { "name": "mempool_spendcoinbase.py", - "time": 4 + "time": 2 }, { "name": "merkle_blocks.py", - "time": 4 + "time": 3 }, { "name": "minchainwork.py", - "time": 16 + "time": 5 }, { "name": "mining.py", - "time": 4 + "time": 2 }, { "name": "multi_rpc.py", - "time": 10 + "time": 4 }, { "name": "multiwallet.py", - "time": 8 + "time": 5 }, { "name": "net.py", - "time": 3 + "time": 2 }, { "name": "notifications.py", - "time": 20 + "time": 5 }, { "name": "nulldummy.py", - "time": 5 + "time": 2 }, { "name": "p2p-acceptblock.py", - "time": 5 + "time": 4 }, { "name": "p2p-compactblocks.py", - "time": 30 + "time": 12 }, { "name": "p2p-feefilter.py", - "time": 19 + "time": 23 + }, + { + "name": "p2p-fingerprint.py", + "time": 8 }, { "name": "p2p-fullblocktest.py", - "time": 133 + "time": 97 }, { "name": "p2p-leaktests.py", - "time": 8 + "time": 7 }, { "name": "p2p-mempool.py", - "time": 12 + "time": 2 }, { "name": "p2p-timeouts.py", - "time": 65 + "time": 64 }, { "name": "preciousblock.py", - "time": 10 + "time": 3 }, { "name": "prioritise_transaction.py", - "time": 9 + "time": 4 }, { "name": "proxy_test.py", - "time": 7 + "time": 3 }, { "name": "pruning.py", - "time": 1527 + "time": 502 }, { "name": "rawtransactions.py", - "time": 38 + "time": 16 }, { "name": "reindex.py", - "time": 27 + "time": 12 }, { "name": "resendwallettransactions.py", - "time": 14 + "time": 5 }, { "name": "rest.py", - "time": 32 + "time": 6 }, { "name": "rpcbind_test.py", - "time": 27 + "time": 24 }, { "name": "rpcnamedargs.py", - "time": 3 + "time": 2 }, { "name": "sendheaders.py", - "time": 42 + "time": 13 }, { "name": "signmessages.py", "time": 2 }, { "name": "signrawtransactions.py", "time": 2 }, { "name": "txn_clone.py", - "time": 5 + "time": 3 }, { "name": "txn_clone.py --mineblock", - "time": 8 + "time": 3 }, { "name": "txn_doublespend.py", - "time": 24 + "time": 3 }, { "name": "txn_doublespend.py --mineblock", - "time": 16 + "time": 3 }, { "name": "uptime.py", - "time": 3 + "time": 2 }, { "name": "wallet.py", - "time": 75 + "time": 31 }, { "name": "wallet_accounts.py", - "time": 26 + "time": 2 }, { "name": "wallet_dump.py", - "time": 12 + "time": 5 }, { "name": "wallet_encryption.py", - "time": 27 + "time": 7 }, { "name": "wallet_hd.py", - "time": 142 + "time": 17 }, { "name": "wallet_receivedby.py", - "time": 21 + "time": 12 }, { "name": "walletbackup.py", - "time": 130 + "time": 100 }, { "name": "zapwallettxes.py", - "time": 26 + "time": 10 }, { "name": "zmq_test.py", - "time": 7 + "time": 11 } ] \ No newline at end of file