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-rw-r--r--src/net_processing.cpp151
1 files changed, 83 insertions, 68 deletions
diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index 72c8e65c6b..7b83583e41 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -143,6 +143,8 @@ static constexpr unsigned int MAX_FEEFILTER_CHANGE_DELAY = 5 * 60;
static constexpr uint32_t MAX_GETCFILTERS_SIZE = 1000;
/** Maximum number of cf hashes that may be requested with one getcfheaders. See BIP 157. */
static constexpr uint32_t MAX_GETCFHEADERS_SIZE = 2000;
+/** the maximum percentage of addresses from our addrman to return in response to a getaddr message. */
+static constexpr size_t MAX_PCT_ADDR_TO_SEND = 23;
struct COrphanTx {
// When modifying, adapt the copy of this definition in tests/DoS_tests.
@@ -479,7 +481,7 @@ static void UpdatePreferredDownload(const CNode& node, CNodeState* state) EXCLUS
nPreferredDownload -= state->fPreferredDownload;
// Whether this node should be marked as a preferred download node.
- state->fPreferredDownload = (!node.fInbound || node.HasPermission(PF_NOBAN)) && !node.fOneShot && !node.fClient;
+ state->fPreferredDownload = (!node.IsInboundConn() || node.HasPermission(PF_NOBAN)) && !node.IsAddrFetchConn() && !node.fClient;
nPreferredDownload += state->fPreferredDownload;
}
@@ -833,22 +835,15 @@ void UpdateLastBlockAnnounceTime(NodeId node, int64_t time_in_seconds)
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(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), pnode->fInbound, pnode->m_manual_connection));
+ mapNodeState.emplace_hint(mapNodeState.end(), std::piecewise_construct, std::forward_as_tuple(nodeid), std::forward_as_tuple(addr, std::move(addrName), pnode->IsInboundConn(), pnode->IsManualConn()));
}
- if(!pnode->fInbound)
+ if(!pnode->IsInboundConn())
PushNodeVersion(*pnode, *connman, GetTime());
}
@@ -1741,16 +1736,27 @@ void static ProcessGetData(CNode& pfrom, const CChainParams& chainparams, CConnm
connman.PushMessage(&pfrom, msgMaker.Make(nSendFlags, NetMsgType::TX, *tx));
mempool.RemoveUnbroadcastTx(tx->GetHash());
// As we're going to send tx, make sure its unconfirmed parents are made requestable.
- for (const auto& txin : tx->vin) {
- auto txinfo = mempool.info(txin.prevout.hash);
- if (txinfo.tx && txinfo.m_time > now - UNCONDITIONAL_RELAY_DELAY) {
- // Relaying a transaction with a recent but unconfirmed parent.
- if (WITH_LOCK(pfrom.m_tx_relay->cs_tx_inventory, return !pfrom.m_tx_relay->filterInventoryKnown.contains(txin.prevout.hash))) {
- LOCK(cs_main);
- State(pfrom.GetId())->m_recently_announced_invs.insert(txin.prevout.hash);
+ std::vector<uint256> parent_ids_to_add;
+ {
+ LOCK(mempool.cs);
+ auto txiter = mempool.GetIter(tx->GetHash());
+ if (txiter) {
+ const CTxMemPool::setEntries& parents = mempool.GetMemPoolParents(*txiter);
+ parent_ids_to_add.reserve(parents.size());
+ for (CTxMemPool::txiter parent_iter : parents) {
+ if (parent_iter->GetTime() > now - UNCONDITIONAL_RELAY_DELAY) {
+ parent_ids_to_add.push_back(parent_iter->GetTx().GetHash());
+ }
}
}
}
+ for (const uint256& parent_txid : parent_ids_to_add) {
+ // Relaying a transaction with a recent but unconfirmed parent.
+ if (WITH_LOCK(pfrom.m_tx_relay->cs_tx_inventory, return !pfrom.m_tx_relay->filterInventoryKnown.contains(parent_txid))) {
+ LOCK(cs_main);
+ State(pfrom.GetId())->m_recently_announced_invs.insert(parent_txid);
+ }
+ }
} else {
vNotFound.push_back(inv);
}
@@ -1971,14 +1977,14 @@ static void ProcessHeadersMessage(CNode& pfrom, CConnman& connman, ChainstateMan
// 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)) {
+ if (pfrom.IsOutboundOrBlockRelayConn()) {
LogPrintf("Disconnecting outbound peer %d -- headers chain has insufficient work\n", pfrom.GetId());
pfrom.fDisconnect = true;
}
}
}
- if (!pfrom.fDisconnect && IsOutboundDisconnectionCandidate(pfrom) && nodestate->pindexBestKnownBlock != nullptr && pfrom.m_tx_relay != nullptr) {
+ if (!pfrom.fDisconnect && pfrom.IsOutboundOrBlockRelayConn() && nodestate->pindexBestKnownBlock != nullptr && pfrom.m_tx_relay != nullptr) {
// If this is an outbound full-relay peer, check to see if we should protect
// it from the bad/lagging chain logic.
// Note that block-relay-only peers are already implicitly protected, so we
@@ -2085,7 +2091,7 @@ void static ProcessOrphanTx(CConnman& connman, CTxMemPool& mempool, std::set<uin
*
* May disconnect from the peer in the case of a bad request.
*
- * @param[in] pfrom The peer that we received the request from
+ * @param[in] peer The peer that we received the request from
* @param[in] chain_params Chain parameters
* @param[in] filter_type The filter type the request is for. Must be basic filters.
* @param[in] start_height The start height for the request
@@ -2095,7 +2101,7 @@ void static ProcessOrphanTx(CConnman& connman, CTxMemPool& mempool, std::set<uin
* @param[out] filter_index The filter index, if the request can be serviced.
* @return True if the request can be serviced.
*/
-static bool PrepareBlockFilterRequest(CNode& pfrom, const CChainParams& chain_params,
+static bool PrepareBlockFilterRequest(CNode& peer, const CChainParams& chain_params,
BlockFilterType filter_type, uint32_t start_height,
const uint256& stop_hash, uint32_t max_height_diff,
const CBlockIndex*& stop_index,
@@ -2103,11 +2109,11 @@ static bool PrepareBlockFilterRequest(CNode& pfrom, const CChainParams& chain_pa
{
const bool supported_filter_type =
(filter_type == BlockFilterType::BASIC &&
- gArgs.GetBoolArg("-peerblockfilters", DEFAULT_PEERBLOCKFILTERS));
+ (peer.GetLocalServices() & NODE_COMPACT_FILTERS));
if (!supported_filter_type) {
LogPrint(BCLog::NET, "peer %d requested unsupported block filter type: %d\n",
- pfrom.GetId(), static_cast<uint8_t>(filter_type));
- pfrom.fDisconnect = true;
+ peer.GetId(), static_cast<uint8_t>(filter_type));
+ peer.fDisconnect = true;
return false;
}
@@ -2118,8 +2124,8 @@ static bool PrepareBlockFilterRequest(CNode& pfrom, const CChainParams& chain_pa
// Check that the stop block exists and the peer would be allowed to fetch it.
if (!stop_index || !BlockRequestAllowed(stop_index, chain_params.GetConsensus())) {
LogPrint(BCLog::NET, "peer %d requested invalid block hash: %s\n",
- pfrom.GetId(), stop_hash.ToString());
- pfrom.fDisconnect = true;
+ peer.GetId(), stop_hash.ToString());
+ peer.fDisconnect = true;
return false;
}
}
@@ -2128,14 +2134,14 @@ static bool PrepareBlockFilterRequest(CNode& pfrom, const CChainParams& chain_pa
if (start_height > stop_height) {
LogPrint(BCLog::NET, "peer %d sent invalid getcfilters/getcfheaders with " /* Continued */
"start height %d and stop height %d\n",
- pfrom.GetId(), start_height, stop_height);
- pfrom.fDisconnect = true;
+ peer.GetId(), start_height, stop_height);
+ peer.fDisconnect = true;
return false;
}
if (stop_height - start_height >= max_height_diff) {
LogPrint(BCLog::NET, "peer %d requested too many cfilters/cfheaders: %d / %d\n",
- pfrom.GetId(), stop_height - start_height + 1, max_height_diff);
- pfrom.fDisconnect = true;
+ peer.GetId(), stop_height - start_height + 1, max_height_diff);
+ peer.fDisconnect = true;
return false;
}
@@ -2153,12 +2159,12 @@ static bool PrepareBlockFilterRequest(CNode& pfrom, const CChainParams& chain_pa
*
* May disconnect from the peer in the case of a bad request.
*
- * @param[in] pfrom The peer that we received the request from
+ * @param[in] peer The peer that we received the request from
* @param[in] vRecv The raw message received
* @param[in] chain_params Chain parameters
* @param[in] connman Pointer to the connection manager
*/
-static void ProcessGetCFilters(CNode& pfrom, CDataStream& vRecv, const CChainParams& chain_params,
+static void ProcessGetCFilters(CNode& peer, CDataStream& vRecv, const CChainParams& chain_params,
CConnman& connman)
{
uint8_t filter_type_ser;
@@ -2171,13 +2177,12 @@ static void ProcessGetCFilters(CNode& pfrom, CDataStream& vRecv, const CChainPar
const CBlockIndex* stop_index;
BlockFilterIndex* filter_index;
- if (!PrepareBlockFilterRequest(pfrom, chain_params, filter_type, start_height, stop_hash,
+ if (!PrepareBlockFilterRequest(peer, chain_params, filter_type, start_height, stop_hash,
MAX_GETCFILTERS_SIZE, stop_index, filter_index)) {
return;
}
std::vector<BlockFilter> filters;
-
if (!filter_index->LookupFilterRange(start_height, stop_index, filters)) {
LogPrint(BCLog::NET, "Failed to find block filter in index: filter_type=%s, start_height=%d, stop_hash=%s\n",
BlockFilterTypeName(filter_type), start_height, stop_hash.ToString());
@@ -2185,9 +2190,9 @@ static void ProcessGetCFilters(CNode& pfrom, CDataStream& vRecv, const CChainPar
}
for (const auto& filter : filters) {
- CSerializedNetMsg msg = CNetMsgMaker(pfrom.GetSendVersion())
+ CSerializedNetMsg msg = CNetMsgMaker(peer.GetSendVersion())
.Make(NetMsgType::CFILTER, filter);
- connman.PushMessage(&pfrom, std::move(msg));
+ connman.PushMessage(&peer, std::move(msg));
}
}
@@ -2196,12 +2201,12 @@ static void ProcessGetCFilters(CNode& pfrom, CDataStream& vRecv, const CChainPar
*
* May disconnect from the peer in the case of a bad request.
*
- * @param[in] pfrom The peer that we received the request from
+ * @param[in] peer The peer that we received the request from
* @param[in] vRecv The raw message received
* @param[in] chain_params Chain parameters
* @param[in] connman Pointer to the connection manager
*/
-static void ProcessGetCFHeaders(CNode& pfrom, CDataStream& vRecv, const CChainParams& chain_params,
+static void ProcessGetCFHeaders(CNode& peer, CDataStream& vRecv, const CChainParams& chain_params,
CConnman& connman)
{
uint8_t filter_type_ser;
@@ -2214,7 +2219,7 @@ static void ProcessGetCFHeaders(CNode& pfrom, CDataStream& vRecv, const CChainPa
const CBlockIndex* stop_index;
BlockFilterIndex* filter_index;
- if (!PrepareBlockFilterRequest(pfrom, chain_params, filter_type, start_height, stop_hash,
+ if (!PrepareBlockFilterRequest(peer, chain_params, filter_type, start_height, stop_hash,
MAX_GETCFHEADERS_SIZE, stop_index, filter_index)) {
return;
}
@@ -2237,13 +2242,13 @@ static void ProcessGetCFHeaders(CNode& pfrom, CDataStream& vRecv, const CChainPa
return;
}
- CSerializedNetMsg msg = CNetMsgMaker(pfrom.GetSendVersion())
+ CSerializedNetMsg msg = CNetMsgMaker(peer.GetSendVersion())
.Make(NetMsgType::CFHEADERS,
filter_type_ser,
stop_index->GetBlockHash(),
prev_header,
filter_hashes);
- connman.PushMessage(&pfrom, std::move(msg));
+ connman.PushMessage(&peer, std::move(msg));
}
/**
@@ -2251,12 +2256,12 @@ static void ProcessGetCFHeaders(CNode& pfrom, CDataStream& vRecv, const CChainPa
*
* May disconnect from the peer in the case of a bad request.
*
- * @param[in] pfrom The peer that we received the request from
+ * @param[in] peer The peer that we received the request from
* @param[in] vRecv The raw message received
* @param[in] chain_params Chain parameters
* @param[in] connman Pointer to the connection manager
*/
-static void ProcessGetCFCheckPt(CNode& pfrom, CDataStream& vRecv, const CChainParams& chain_params,
+static void ProcessGetCFCheckPt(CNode& peer, CDataStream& vRecv, const CChainParams& chain_params,
CConnman& connman)
{
uint8_t filter_type_ser;
@@ -2268,7 +2273,7 @@ static void ProcessGetCFCheckPt(CNode& pfrom, CDataStream& vRecv, const CChainPa
const CBlockIndex* stop_index;
BlockFilterIndex* filter_index;
- if (!PrepareBlockFilterRequest(pfrom, chain_params, filter_type, /*start_height=*/0, stop_hash,
+ if (!PrepareBlockFilterRequest(peer, chain_params, filter_type, /*start_height=*/0, stop_hash,
/*max_height_diff=*/std::numeric_limits<uint32_t>::max(),
stop_index, filter_index)) {
return;
@@ -2289,12 +2294,12 @@ static void ProcessGetCFCheckPt(CNode& pfrom, CDataStream& vRecv, const CChainPa
}
}
- CSerializedNetMsg msg = CNetMsgMaker(pfrom.GetSendVersion())
+ CSerializedNetMsg msg = CNetMsgMaker(peer.GetSendVersion())
.Make(NetMsgType::CFCHECKPT,
filter_type_ser,
stop_index->GetBlockHash(),
headers);
- connman.PushMessage(&pfrom, std::move(msg));
+ connman.PushMessage(&peer, std::move(msg));
}
void ProcessMessage(
@@ -2341,11 +2346,11 @@ void ProcessMessage(
vRecv >> nVersion >> nServiceInt >> nTime >> addrMe;
nSendVersion = std::min(nVersion, PROTOCOL_VERSION);
nServices = ServiceFlags(nServiceInt);
- if (!pfrom.fInbound)
+ if (!pfrom.IsInboundConn())
{
connman.SetServices(pfrom.addr, nServices);
}
- if (!pfrom.fInbound && !pfrom.fFeeler && !pfrom.m_manual_connection && !HasAllDesirableServiceFlags(nServices))
+ if (pfrom.ExpectServicesFromConn() && !HasAllDesirableServiceFlags(nServices))
{
LogPrint(BCLog::NET, "peer=%d does not offer the expected services (%08x offered, %08x expected); disconnecting\n", pfrom.GetId(), nServices, GetDesirableServiceFlags(nServices));
pfrom.fDisconnect = true;
@@ -2372,20 +2377,20 @@ void ProcessMessage(
if (!vRecv.empty())
vRecv >> fRelay;
// Disconnect if we connected to ourself
- if (pfrom.fInbound && !connman.CheckIncomingNonce(nNonce))
+ if (pfrom.IsInboundConn() && !connman.CheckIncomingNonce(nNonce))
{
LogPrintf("connected to self at %s, disconnecting\n", pfrom.addr.ToString());
pfrom.fDisconnect = true;
return;
}
- if (pfrom.fInbound && addrMe.IsRoutable())
+ if (pfrom.IsInboundConn() && addrMe.IsRoutable())
{
SeenLocal(addrMe);
}
// Be shy and don't send version until we hear
- if (pfrom.fInbound)
+ if (pfrom.IsInboundConn())
PushNodeVersion(pfrom, connman, GetAdjustedTime());
if (nVersion >= WTXID_RELAY_VERSION) {
@@ -2429,7 +2434,7 @@ void ProcessMessage(
UpdatePreferredDownload(pfrom, State(pfrom.GetId()));
}
- if (!pfrom.fInbound && pfrom.IsAddrRelayPeer())
+ if (!pfrom.IsInboundConn() && pfrom.IsAddrRelayPeer())
{
// Advertise our address
if (fListen && !::ChainstateActive().IsInitialBlockDownload())
@@ -2473,8 +2478,7 @@ void ProcessMessage(
}
// Feeler connections exist only to verify if address is online.
- if (pfrom.fFeeler) {
- assert(pfrom.fInbound == false);
+ if (pfrom.IsFeelerConn()) {
pfrom.fDisconnect = true;
}
return;
@@ -2494,7 +2498,7 @@ void ProcessMessage(
{
pfrom.SetRecvVersion(std::min(pfrom.nVersion.load(), PROTOCOL_VERSION));
- if (!pfrom.fInbound) {
+ if (!pfrom.IsInboundConn()) {
// Mark this node as currently connected, so we update its timestamp later.
LOCK(cs_main);
State(pfrom.GetId())->fCurrentlyConnected = true;
@@ -2603,7 +2607,7 @@ void ProcessMessage(
connman.AddNewAddresses(vAddrOk, pfrom.addr, 2 * 60 * 60);
if (vAddr.size() < 1000)
pfrom.fGetAddr = false;
- if (pfrom.fOneShot)
+ if (pfrom.IsAddrFetchConn())
pfrom.fDisconnect = true;
return;
}
@@ -2999,8 +3003,19 @@ void ProcessMessage(
else if (state.GetResult() == TxValidationResult::TX_MISSING_INPUTS)
{
bool fRejectedParents = false; // It may be the case that the orphans parents have all been rejected
+
+ // Deduplicate parent txids, so that we don't have to loop over
+ // the same parent txid more than once down below.
+ std::vector<uint256> unique_parents;
+ unique_parents.reserve(tx.vin.size());
for (const CTxIn& txin : tx.vin) {
- if (recentRejects->contains(txin.prevout.hash)) {
+ // We start with all parents, and then remove duplicates below.
+ unique_parents.push_back(txin.prevout.hash);
+ }
+ std::sort(unique_parents.begin(), unique_parents.end());
+ unique_parents.erase(std::unique(unique_parents.begin(), unique_parents.end()), unique_parents.end());
+ for (const uint256& parent_txid : unique_parents) {
+ if (recentRejects->contains(parent_txid)) {
fRejectedParents = true;
break;
}
@@ -3009,14 +3024,14 @@ void ProcessMessage(
uint32_t nFetchFlags = GetFetchFlags(pfrom);
const auto current_time = GetTime<std::chrono::microseconds>();
- for (const CTxIn& txin : tx.vin) {
+ for (const uint256& parent_txid : unique_parents) {
// Here, we only have the txid (and not wtxid) of the
// inputs, so we only request in txid mode, even for
// wtxidrelay peers.
// Eventually we should replace this with an improved
// protocol for getting all unconfirmed parents.
- CInv _inv(MSG_TX | nFetchFlags, txin.prevout.hash);
- pfrom.AddKnownTx(txin.prevout.hash);
+ CInv _inv(MSG_TX | nFetchFlags, parent_txid);
+ pfrom.AddKnownTx(parent_txid);
if (!AlreadyHave(_inv, mempool)) RequestTx(State(pfrom.GetId()), ToGenTxid(_inv), current_time);
}
AddOrphanTx(ptx, pfrom.GetId());
@@ -3487,7 +3502,7 @@ void ProcessMessage(
// 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) {
+ if (!pfrom.IsInboundConn()) {
LogPrint(BCLog::NET, "Ignoring \"getaddr\" from outbound connection. peer=%d\n", pfrom.GetId());
return;
}
@@ -3507,9 +3522,9 @@ void ProcessMessage(
pfrom.vAddrToSend.clear();
std::vector<CAddress> vAddr;
if (pfrom.HasPermission(PF_ADDR)) {
- vAddr = connman.GetAddresses();
+ vAddr = connman.GetAddresses(MAX_ADDR_TO_SEND, MAX_PCT_ADDR_TO_SEND);
} else {
- vAddr = connman.GetAddresses(pfrom.addr.GetNetwork());
+ vAddr = connman.GetAddresses(pfrom.addr.GetNetwork(), MAX_ADDR_TO_SEND, MAX_PCT_ADDR_TO_SEND);
}
FastRandomContext insecure_rand;
for (const CAddress &addr : vAddr) {
@@ -3770,7 +3785,7 @@ bool PeerLogicValidation::MaybeDiscourageAndDisconnect(CNode& pnode)
return false;
}
- if (pnode.m_manual_connection) {
+ if (pnode.IsManualConn()) {
// We never disconnect or discourage manual peers for bad behavior
LogPrintf("Warning: not punishing manually connected peer %d!\n", peer_id);
return false;
@@ -3891,7 +3906,7 @@ void PeerLogicValidation::ConsiderEviction(CNode& pto, int64_t time_in_seconds)
CNodeState &state = *State(pto.GetId());
const CNetMsgMaker msgMaker(pto.GetSendVersion());
- if (!state.m_chain_sync.m_protect && IsOutboundDisconnectionCandidate(pto) && state.fSyncStarted) {
+ if (!state.m_chain_sync.m_protect && pto.IsOutboundOrBlockRelayConn() && state.fSyncStarted) {
// This is an outbound peer subject to disconnection if they don't
// announce a block with as much work as the current tip within
// CHAIN_SYNC_TIMEOUT + HEADERS_RESPONSE_TIME seconds (note: if
@@ -3953,7 +3968,7 @@ void PeerLogicValidation::EvictExtraOutboundPeers(int64_t time_in_seconds)
AssertLockHeld(cs_main);
// Ignore non-outbound peers, or nodes marked for disconnect already
- if (!IsOutboundDisconnectionCandidate(*pnode) || pnode->fDisconnect) return;
+ if (!pnode->IsOutboundOrBlockRelayConn() || pnode->fDisconnect) return;
CNodeState *state = State(pnode->GetId());
if (state == nullptr) return; // shouldn't be possible, but just in case
// Don't evict our protected peers
@@ -4131,7 +4146,7 @@ bool PeerLogicValidation::SendMessages(CNode* pto)
// Start block sync
if (pindexBestHeader == nullptr)
pindexBestHeader = ::ChainActive().Tip();
- bool fFetch = state.fPreferredDownload || (nPreferredDownload == 0 && !pto->fClient && !pto->fOneShot); // 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->IsAddrFetchConn()); // Download if this is a nice peer, or we have no nice peers and this one might do.
if (!state.fSyncStarted && !pto->fClient && !fImporting && !fReindex) {
// Only actively request headers from a single peer, unless we're close to today.
if ((nSyncStarted == 0 && fFetch) || pindexBestHeader->GetBlockTime() > GetAdjustedTime() - 24 * 60 * 60) {
@@ -4316,7 +4331,7 @@ bool PeerLogicValidation::SendMessages(CNode* pto)
bool fSendTrickle = pto->HasPermission(PF_NOBAN);
if (pto->m_tx_relay->nNextInvSend < current_time) {
fSendTrickle = true;
- if (pto->fInbound) {
+ if (pto->IsInboundConn()) {
pto->m_tx_relay->nNextInvSend = std::chrono::microseconds{connman->PoissonNextSendInbound(nNow, INVENTORY_BROADCAST_INTERVAL)};
} else {
// Use half the delay for outbound peers, as there is less privacy concern for them.