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// 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<int64_t> nTimeBestReceived(0);
struct IteratorComparator {
template <typename I> 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<uint256, COrphanTx> mapOrphanTransactions GUARDED_BY(cs_main);
std::map<COutPoint,
std::set<std::map<uint256, COrphanTx>::iterator, IteratorComparator>>
mapOrphanTransactionsByPrev GUARDED_BY(cs_main);
void EraseOrphansFor(NodeId peer) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
static size_t vExtraTxnForCompactIt = 0;
static std::vector<std::pair<uint256, CTransactionRef>>
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<uint256, std::pair<NodeId, bool>> mapBlockSource GUARDED_BY(cs_main);
/**
* Filter for transactions that were recently rejected by AcceptToMemoryPool.
* These are not rerequested until the chain tip changes, at which point the
* entire filter is reset.
*
* Without this filter we'd be re-requesting txs from each of our peers,
* increasing bandwidth consumption considerably. For instance, with 100 peers,
* half of which relay a tx we don't accept, that might be a 50x bandwidth
* increase. A flooding attacker attempting to roll-over the filter using
* minimum-sized, 60byte, transactions might manage to send 1000/sec if we have
* fast peers, so we pick 120,000 to give our peers a two minute window to send
* invs to us.
*
* Decreasing the false positive rate is fairly cheap, so we pick one in a
* million to make it highly unlikely for users to have issues with this filter.
*
* Memory used: 1.3 MB
*/
std::unique_ptr<CRollingBloomFilter> 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<PartiallyDownloadedBlock> partialBlock;
};
std::map<uint256, std::pair<NodeId, std::list<QueuedBlock>::iterator>>
mapBlocksInFlight GUARDED_BY(cs_main);
/** Stack of nodes which we have set to announce using compact blocks */
std::list<NodeId> lNodesAnnouncingHeaderAndIDs;
/** 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<uint256, CTransactionRef> MapRelay;
MapRelay mapRelay GUARDED_BY(cs_main);
/**
* Expiration-time ordered list of (expire time, relay map entry) pairs,
* protected by cs_main).
*/
std::deque<std::pair<int64_t, MapRelay::iterator>>
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<CBlockReject> 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<QueuedBlock> vBlocksInFlight;
//! When the first entry in vBlocksInFlight started downloading. Don't care
//! when vBlocksInFlight is empty.
int64_t nDownloadingSince;
int nBlocksInFlight;
int nBlocksInFlightValidHeaders;
//! Whether we consider this a preferred download peer.
bool fPreferredDownload;
//! Whether this peer wants invs or headers (when possible) for block
//! announcements.
bool fPreferHeaders;
//! Whether this peer wants invs or cmpctblocks (when possible) for block
//! announcements.
bool fPreferHeaderAndIDs;
/**
* Whether this peer will send us cmpctblocks if we request them.
* This is not used to gate request logic, as we really only care about
* fSupportsDesiredCmpctVersion, but is used as a flag to "lock in" the
* version of compact blocks 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<NodeId, CNodeState> mapNodeState GUARDED_BY(cs_main);
static CNodeState *State(NodeId pnode) EXCLUSIVE_LOCKS_REQUIRED(cs_main) {
std::map<NodeId, CNodeState>::iterator it = mapNodeState.find(pnode);
if (it == mapNodeState.end()) {
return nullptr;
}
return &it->second;
}
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<uint256,
std::pair<NodeId, std::list<QueuedBlock>::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<QueuedBlock>::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<uint256,
std::pair<NodeId, std::list<QueuedBlock>::iterator>>::iterator
itInFlight = mapBlocksInFlight.find(hash);
if (itInFlight != mapBlocksInFlight.end() &&
itInFlight->second.first == nodeid) {
if (pit) {
*pit = &itInFlight->second.second;
}
return false;
}
// Make sure it's not listed somewhere already.
MarkBlockAsReceived(hash);
std::list<QueuedBlock>::iterator it = state->vBlocksInFlight.insert(
state->vBlocksInFlight.end(),
{hash, pindex, pindex != nullptr,
std::unique_ptr<PartiallyDownloadedBlock>(
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<NodeId>::iterator it = lNodesAnnouncingHeaderAndIDs.begin();
it != lNodesAnnouncingHeaderAndIDs.end(); it++) {
if (*it == nodeid) {
lNodesAnnouncingHeaderAndIDs.erase(it);
lNodesAnnouncingHeaderAndIDs.push_back(nodeid);
return;
}
}
connman->ForNode(nodeid, [&connman](CNode *pfrom) {
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<const CBlockIndex *> &vBlocks,
NodeId &nodeStaller,
const Consensus::Params &consensusParams)
EXCLUSIVE_LOCKS_REQUIRED(cs_main) {
if (count == 0) {
return;
}
vBlocks.reserve(vBlocks.size() + count);
CNodeState *state = State(nodeid);
assert(state != nullptr);
// Make sure pindexBestKnownBlock is up to date, we'll need it.
ProcessBlockAvailability(nodeid);
if (state->pindexBestKnownBlock == nullptr ||
state->pindexBestKnownBlock->nChainWork <
chainActive.Tip()->nChainWork ||
state->pindexBestKnownBlock->nChainWork < nMinimumChainWork) {
// This peer has nothing interesting.
return;
}
if (state->pindexLastCommonBlock == nullptr) {
// Bootstrap quickly by guessing a parent of our best tip is the forking
// point. Guessing wrong in either direction is not a problem.
state->pindexLastCommonBlock = chainActive[std::min(
state->pindexBestKnownBlock->nHeight, chainActive.Height())];
}
// If the peer reorganized, our previous pindexLastCommonBlock may not be an
// ancestor of its current tip anymore. Go back enough to fix that.
state->pindexLastCommonBlock = LastCommonAncestor(
state->pindexLastCommonBlock, state->pindexBestKnownBlock);
if (state->pindexLastCommonBlock == state->pindexBestKnownBlock) {
return;
}
std::vector<const CBlockIndex *> vToFetch;
const CBlockIndex *pindexWalk = state->pindexLastCommonBlock;
// Never fetch further than the best block we know the peer has, or more
// than BLOCK_DOWNLOAD_WINDOW + 1 beyond the last linked block we have in
// common with this peer. The +1 is so we can detect stalling, namely if we
// would be able to download that next block if the window were 1 larger.
int nWindowEnd =
state->pindexLastCommonBlock->nHeight + BLOCK_DOWNLOAD_WINDOW;
int nMaxHeight =
std::min<int>(state->pindexBestKnownBlock->nHeight, nWindowEnd + 1);
NodeId waitingfor = -1;
while (pindexWalk->nHeight < nMaxHeight) {
// Read up to 128 (or more, if more blocks than that are needed)
// successors of pindexWalk (towards pindexBestKnownBlock) into
// vToFetch. We fetch 128, because CBlockIndex::GetAncestor may be as
// expensive as iterating over ~100 CBlockIndex* entries anyway.
int nToFetch = std::min(nMaxHeight - pindexWalk->nHeight,
std::max<int>(count - vBlocks.size(), 128));
vToFetch.resize(nToFetch);
pindexWalk = state->pindexBestKnownBlock->GetAncestor(
pindexWalk->nHeight + nToFetch);
vToFetch[nToFetch - 1] = pindexWalk;
for (unsigned int i = nToFetch - 1; i > 0; i--) {
vToFetch[i - 1] = vToFetch[i]->pprev;
}
// Iterate over those blocks in vToFetch (in forward direction), adding
// the ones that are not yet downloaded and not in flight to vBlocks. In
// the 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<uint256, COrphanTx>::iterator it =
mapOrphanTransactions.find(hash);
if (it == mapOrphanTransactions.end()) {
return 0;
}
for (const CTxIn &txin : it->second.tx->vin) {
auto itPrev = mapOrphanTransactionsByPrev.find(txin.prevout);
if (itPrev == mapOrphanTransactionsByPrev.end()) {
continue;
}
itPrev->second.erase(it);
if (itPrev->second.empty()) {
mapOrphanTransactionsByPrev.erase(itPrev);
}
}
mapOrphanTransactions.erase(it);
return 1;
}
void EraseOrphansFor(NodeId peer) {
int nErased = 0;
std::map<uint256, COrphanTx>::iterator iter = mapOrphanTransactions.begin();
while (iter != mapOrphanTransactions.end()) {
// Increment to avoid iterator becoming invalid.
std::map<uint256, COrphanTx>::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<uint256, COrphanTx>::iterator iter =
mapOrphanTransactions.begin();
while (iter != mapOrphanTransactions.end()) {
std::map<uint256, COrphanTx>::iterator maybeErase = iter++;
if (maybeErase->second.nTimeExpire <= nNow) {
nErased += EraseOrphanTx(maybeErase->second.tx->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<uint256, COrphanTx>::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 and
// we fully-validated them at some point.
static bool BlockRequestAllowed(const CBlockIndex *pindex,
const Consensus::Params &consensusParams) {
AssertLockHeld(cs_main);
if (chainActive.Contains(pindex)) {
return true;
}
return pindex->IsValid(BlockValidity::SCRIPTS) &&
(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<const CBlock> &pblock, const CBlockIndex *pindex,
const std::vector<CTransactionRef> &vtxConflicted) {
LOCK(cs_main);
std::vector<uint256> 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<const CBlock>
most_recent_block GUARDED_BY(cs_most_recent_block);
static std::shared_ptr<const CBlockHeaderAndShortTxIDs>
most_recent_compact_block GUARDED_BY(cs_most_recent_block);
static uint256 most_recent_block_hash GUARDED_BY(cs_most_recent_block);
void PeerLogicValidation::NewPoWValidBlock(
const CBlockIndex *pindex, const std::shared_ptr<const CBlock> &pblock) {
std::shared_ptr<const CBlockHeaderAndShortTxIDs> pcmpctblock =
std::make_shared<const CBlockHeaderAndShortTxIDs>(*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<uint256> vHashes;
const CBlockIndex *pindexToAnnounce = pindexNew;
while (pindexToAnnounce != pindexFork) {
vHashes.push_back(pindexToAnnounce->GetBlockHash());
pindexToAnnounce = pindexToAnnounce->pprev;
if (vHashes.size() == MAX_BLOCKS_TO_ANNOUNCE) {
// Limit announcements in case of a huge reorganization. Rely on
// the peer's synchronization mechanism in that case.
break;
}
}
// Relay inventory, but don't relay old inventory during initial block
// download.
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<uint256, std::pair<NodeId, bool>>::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<std::pair<uint64_t, CNode *>, 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<bool> &interruptMsgProc) {
const Consensus::Params &consensusParams =
config.GetChainParams().GetConsensus();
std::deque<CInv>::iterator it = pfrom->vRecvGetData.begin();
std::vector<CInv> 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<const CBlock> a_recent_block;
{
LOCK(cs_most_recent_block);
a_recent_block = most_recent_block;
}
CValidationState dummy;
ActivateBestChain(config, dummy, a_recent_block);
}
send = BlockRequestAllowed(mi->second, consensusParams);
if (!send) {
LogPrint(BCLog::NET,
"%s: ignoring request from peer=%i for old "
"block that isn't in the main chain\n",
__func__, pfrom->GetId());
}
}
// Disconnect node in case we have reached the outbound limit
// for serving historical blocks.
// Never disconnect whitelisted nodes.
if (send && connman->OutboundTargetReached(true) &&
(((pindexBestHeader != nullptr) &&
(pindexBestHeader->GetBlockTime() -
mi->second->GetBlockTime() >
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<unsigned int, uint256> 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<CInv> 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<CBlockHeader> &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<const CBlockIndex *> vToFetch;
const CBlockIndex *pindexWalk = pindexLast;
// Calculate all the blocks we'd need to switch to pindexLast, up to
// a limit.
while (pindexWalk && !chainActive.Contains(pindexWalk) &&
vToFetch.size() <= MAX_BLOCKS_IN_TRANSIT_PER_PEER) {
if (!pindexWalk->nStatus.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<CInv> vGetData;
// Download as much as possible, from earliest to latest.
for (const CBlockIndex *pindex : reverse_iterate(vToFetch)) {
if (nodestate->nBlocksInFlight >=
MAX_BLOCKS_IN_TRANSIT_PER_PEER) {
// Can't download any more from this peer
break;
}
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<bool> &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
LogPrint(BCLog::NET,
"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();
}
LogPrint(BCLog::NET,
"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;
LogPrintf(
"New outbound peer connected: version: %d, blocks=%d, "
"peer=%d%s\n",
pfrom->nVersion.load(), pfrom->nStartingHeight, pfrom->GetId(),
(fLogIPs ? strprintf(", peeraddr=%s", pfrom->addr.ToString())
: ""));
}
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<CAddress> 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<CAddress> 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<CInv> 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<CInv> 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<CInv> 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<const CBlock> 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<const CBlock> recent_block;
{
LOCK(cs_most_recent_block);
if (most_recent_block_hash == req.blockhash) {
recent_block = most_recent_block;
}
// Unlock cs_most_recent_block to avoid cs_main lock inversion
}
if (recent_block) {
SendBlockTransactions(*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()) {
LogPrint(BCLog::NET,
"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 (!BlockRequestAllowed(pindex, chainparams.GetConsensus())) {
LogPrint(BCLog::NET,
"%s: ignoring request from peer=%i for old block "
"header that isn't in the main chain\n",
__func__, pfrom->GetId());
return 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<CBlock> vHeaders;
int nLimit = MAX_HEADERS_RESULTS;
LogPrint(BCLog::NET, "getheaders %d to %s from peer=%d\n",
(pindex ? pindex->nHeight : -1),
hashStop.IsNull() ? "end" : hashStop.ToString(),
pfrom->GetId());
for (; pindex; pindex = chainActive.Next(pindex)) {
vHeaders.push_back(pindex->GetBlockHeader());
if (--nLimit <= 0 || pindex->GetBlockHash() == hashStop) {
break;
}
}
// pindex can be nullptr either if we sent chainActive.Tip() OR
// if our peer has chainActive.Tip() (and thus we are sending an empty
// headers message). In both cases it's safe to update
// pindexBestHeaderSent to be our tip.
//
// It is important that we simply reset the BestHeaderSent value here,
// and not max(BestHeaderSent, newHeaderSent). We might have announced
// the currently-being-connected tip using a compact block, which
// resulted in the peer sending a headers request, which we respond to
// without the new block. By resetting the BestHeaderSent, we ensure we
// will re-announce the new block via headers (or compact blocks again)
// in the SendMessages logic.
nodestate->pindexBestHeaderSent = pindex ? pindex : chainActive.Tip();
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<COutPoint> vWorkQueue;
std::vector<uint256> 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<NodeId> 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) {
LogPrintf("Peer %d sent us invalid header via cmpctblock\n",
pfrom->GetId());
LOCK(cs_main);
Misbehaving(pfrom, nDoS, state.GetRejectReason());
} else {
LogPrint(BCLog::NET,
"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<CBlock> pblock = std::make_shared<CBlock>();
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<uint256,
std::pair<NodeId, std::list<QueuedBlock>::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<CInv> 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<QueuedBlock>::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<CInv> 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<CTransactionRef> dummy;
status = tempBlock.FillBlock(*pblock, dummy);
if (status == READ_STATUS_OK) {
fBlockReconstructed = true;
}
}
} else {
if (fAlreadyInFlight) {
// We requested this block, but its far into the future, so
// our mempool will probably be useless - request the block
// normally.
std::vector<CInv> vInv(1);
vInv[0] = CInv(MSG_BLOCK, 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<CBlock> pblock = std::make_shared<CBlock>();
bool fBlockRead = false;
{
LOCK(cs_main);
std::map<uint256,
std::pair<NodeId, std::list<QueuedBlock>::iterator>>::
iterator it = mapBlocksInFlight.find(resp.blockhash);
if (it == mapBlocksInFlight.end() ||
!it->second.second->partialBlock ||
it->second.first != pfrom->GetId()) {
LogPrint(BCLog::NET,
"Peer %d sent us block transactions for block "
"we weren't expecting\n",
pfrom->GetId());
return 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<CInv> 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<CBlockHeader> headers;
// Bypass the normal CBlock deserialization, as we don't want to risk
// deserializing 2000 full blocks.
unsigned int nCount = ReadCompactSize(vRecv);
if (nCount > MAX_HEADERS_RESULTS) {
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<CBlock> pblock = std::make_shared<CBlock>();
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<CAddress> 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<uint8_t> 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<bool> &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<CNetMessage> msgs;
{
LOCK(pfrom->cs_vProcessMsg);
if (pfrom->vProcessMsg.empty()) {
return false;
}
// Just take one message
msgs.splice(msgs.begin(), pfrom->vProcessMsg,
pfrom->vProcessMsg.begin());
pfrom->nProcessQueueSize -=
msgs.front().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) {
LogPrint(BCLog::NET,
"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)) {
LogPrint(BCLog::NET, "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) {
LogPrint(
BCLog::NET, "%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
LogPrint(
BCLog::NET,
"%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
LogPrint(BCLog::NET, "%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
LogPrint(BCLog::NET, "%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) {
LogPrint(BCLog::NET, "%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()
: "<none>");
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()
: "<none>",
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<int64_t>::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<uint256>::iterator a,
std::set<uint256>::iterator b) {
/* As std::make_heap produces a max-heap, we want the entries with the
* fewest ancestors/highest fee to sort later. */
return mp->CompareDepthAndScore(*b, *a);
}
};
}
bool PeerLogicValidation::SendMessages(const Config &config, CNode *pto,
std::atomic<bool> &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<CAddress> 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<CBlock> 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<CInv> vInv;
{
LOCK(pto->cs_inventory);
vInv.reserve(std::max<size_t>(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<std::set<uint256>::iterator> vInvTx;
vInvTx.reserve(pto->setInventoryTxToSend.size());
for (std::set<uint256>::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<uint256>::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<int64_t>::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<int64_t>::max();
}
}
// Check that outbound peers have reasonable chains GetTime() is used by
// this anti-DoS logic so we can test this using mocktime.
ConsiderEviction(pto, GetTime());
//
// Message: getdata (blocks)
//
std::vector<CInv> vGetData;
if (!pto->fClient && (fFetch || !IsInitialBlockDownload()) &&
state.nBlocksInFlight < MAX_BLOCKS_IN_TRANSIT_PER_PEER) {
std::vector<const CBlockIndex *> vToDownload;
NodeId staller = -1;
FindNextBlocksToDownload(pto->GetId(),
MAX_BLOCKS_IN_TRANSIT_PER_PEER -
state.nBlocksInFlight,
vToDownload, staller, consensusParams);
for (const CBlockIndex *pindex : vToDownload) {
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;

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