Merge #15759: p2p: Add 2 outbound block-relay-only connections

0ba08020c9791f7caf5986ad6490c16a2b66cd83 Disconnect peers violating blocks-only mode (Suhas Daftuar)
937eba91e1550bc3038dc541c236ac83e0a0e6d5 doc: improve comments relating to block-relay-only peers (Suhas Daftuar)
430f489027f15c1e4948ea4378954df24e3fee88 Don't relay addr messages to block-relay-only peers (Suhas Daftuar)
3a5e885306ea954d7eccdc11502e91a51dab8ec6 Add 2 outbound block-relay-only connections (Suhas Daftuar)
b83f51a4bbe29bf130a2b0c0e85e5bffea107f75 Add comment explaining intended use of m_tx_relay (Suhas Daftuar)
e75c39cd425f8c4e5b6bbb2beecb9c80034fefe1 Check that tx_relay is initialized before access (Suhas Daftuar)
c4aa2ba82211ea5988ed7fe21e1b08bc3367e6d4 [refactor] Change tx_relay structure to be unique_ptr (Suhas Daftuar)
4de0dbac9b286c42a9b10132b7c2d76712f1a319 [refactor] Move tx relay state to separate structure (Suhas Daftuar)
26a93bce29fd813e1402b013f402869c25b656d1 Remove unused variable (Suhas Daftuar)

Pull request description:

  Transaction relay is optimized for a combination of redundancy/robustness as well as bandwidth minimization -- as a result transaction relay leaks information that adversaries can use to infer the network topology.

  Network topology is better kept private for (at least) two reasons:

  (a) Knowledge of the network graph can make it easier to find the source IP of a given transaction.

  (b) Knowledge of the network graph could be used to split a target node or nodes from the honest network (eg by knowing which peers to attack in order to achieve a network split).

  We can eliminate the risks of (b) by separating block relay from transaction relay; inferring network connectivity from the relay of blocks/block headers is much more expensive for an adversary.

  After this commit, bitcoind will make 2 additional outbound connections that are only used for block relay. (In the future, we might consider rotating our transaction-relay peers to help limit the effects of (a).)

ACKs for top commit:
  sipa:
    ACK 0ba08020c9791f7caf5986ad6490c16a2b66cd83
  ajtowns:
    ACK 0ba08020c9791f7caf5986ad6490c16a2b66cd83 -- code review, ran tests. ran it on mainnet for a couple of days with MAX_BLOCKS_ONLY_CONNECTIONS upped from 2 to 16 and didn't observe any unexpected behaviour: it disconnected a couple of peers that tried sending inv's, and it successfully did compact block relay with some block relay peers.
  TheBlueMatt:
    re-utACK 0ba08020c9791f7caf5986ad6490c16a2b66cd83. Pointed out that stats.fRelayTxes was sometimes uninitialized for blocksonly peers (though its not a big deal and only effects RPC), which has since been fixed here. Otherwise changes are pretty trivial so looks good.
  jnewbery:
    utACK 0ba08020c9791f7caf5986ad6490c16a2b66cd83
  jamesob:
    ACK https://github.com/bitcoin/bitcoin/commit/0ba08020c9791f7caf5986ad6490c16a2b66cd83

Tree-SHA512: 4c3629434472c7dd4125253417b1be41967a508c3cfec8af5a34cad685464fbebbb6558f0f8f5c0d4463e3ffa4fa3aabd58247692cb9ab8395f4993078b9bcdf

1 files changed, 181 insertions, 150 deletions

diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index 520dfcbb66..7f2fea5584 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -262,7 +262,7 @@ struct CNodeState {
     bool fSupportsDesiredCmpctVersion;
 
     /** State used to enforce CHAIN_SYNC_TIMEOUT
-      * Only in effect for outbound, non-manual connections, with
+      * Only in effect for outbound, non-manual, full-relay 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:
@@ -425,7 +425,7 @@ static void PushNodeVersion(CNode *pnode, CConnman* connman, int64_t nTime)
     CAddress addrMe = CAddress(CService(), nLocalNodeServices);
 
     connman->PushMessage(pnode, CNetMsgMaker(INIT_PROTO_VERSION).Make(NetMsgType::VERSION, PROTOCOL_VERSION, (uint64_t)nLocalNodeServices, nTime, addrYou, addrMe,
-            nonce, strSubVersion, nNodeStartingHeight, ::g_relay_txes));
+            nonce, strSubVersion, nNodeStartingHeight, ::g_relay_txes && pnode->m_tx_relay != nullptr));
 
     if (fLogIPs) {
         LogPrint(BCLog::NET, "send version message: version %d, blocks=%d, us=%s, them=%s, peer=%d\n", PROTOCOL_VERSION, nNodeStartingHeight, addrMe.ToString(), addrYou.ToString(), nodeid);
@@ -757,7 +757,7 @@ void UpdateLastBlockAnnounceTime(NodeId node, int64_t time_in_seconds)
 }
 
 // Returns true for outbound peers, excluding manual connections, feelers, and
-// one-shots
+// one-shots.
 static bool IsOutboundDisconnectionCandidate(const CNode *node)
 {
     return !(node->fInbound || node->m_manual_connection || node->fFeeler || node->fOneShot);
@@ -1330,7 +1330,7 @@ static void RelayAddress(const CAddress& addr, bool fReachable, CConnman* connma
     assert(nRelayNodes <= best.size());
 
     auto sortfunc = [&best, &hasher, nRelayNodes](CNode* pnode) {
-        if (pnode->nVersion >= CADDR_TIME_VERSION) {
+        if (pnode->nVersion >= CADDR_TIME_VERSION && pnode->IsAddrRelayPeer()) {
             uint64_t hashKey = CSipHasher(hasher).Write(pnode->GetId()).Finalize();
             for (unsigned int i = 0; i < nRelayNodes; i++) {
                  if (hashKey > best[i].first) {
@@ -1449,11 +1449,11 @@ void static ProcessGetBlockData(CNode* pfrom, const CChainParams& chainparams, c
             {
                 bool sendMerkleBlock = false;
                 CMerkleBlock merkleBlock;
-                {
-                    LOCK(pfrom->cs_filter);
-                    if (pfrom->pfilter) {
+                if (pfrom->m_tx_relay != nullptr) {
+                    LOCK(pfrom->m_tx_relay->cs_filter);
+                    if (pfrom->m_tx_relay->pfilter) {
                         sendMerkleBlock = true;
-                        merkleBlock = CMerkleBlock(*pblock, *pfrom->pfilter);
+                        merkleBlock = CMerkleBlock(*pblock, *pfrom->m_tx_relay->pfilter);
                     }
                 }
                 if (sendMerkleBlock) {
@@ -1513,7 +1513,12 @@ void static ProcessGetData(CNode* pfrom, const CChainParams& chainparams, CConnm
     std::deque<CInv>::iterator it = pfrom->vRecvGetData.begin();
     std::vector<CInv> vNotFound;
     const CNetMsgMaker msgMaker(pfrom->GetSendVersion());
-    {
+
+    // Note that if we receive a getdata for a MSG_TX or MSG_WITNESS_TX from a
+    // block-relay-only outbound peer, we will stop processing further getdata
+    // messages from this peer (likely resulting in our peer eventually
+    // disconnecting us).
+    if (pfrom->m_tx_relay != nullptr) {
         LOCK(cs_main);
 
         while (it != pfrom->vRecvGetData.end() && (it->type == MSG_TX || it->type == MSG_WITNESS_TX)) {
@@ -1533,11 +1538,11 @@ void static ProcessGetData(CNode* pfrom, const CChainParams& chainparams, CConnm
             if (mi != mapRelay.end()) {
                 connman->PushMessage(pfrom, msgMaker.Make(nSendFlags, NetMsgType::TX, *mi->second));
                 push = true;
-            } else if (pfrom->timeLastMempoolReq) {
+            } else if (pfrom->m_tx_relay->timeLastMempoolReq) {
                 auto txinfo = 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) {
+                if (txinfo.tx && txinfo.nTime <= pfrom->m_tx_relay->timeLastMempoolReq) {
                     connman->PushMessage(pfrom, msgMaker.Make(nSendFlags, NetMsgType::TX, *txinfo.tx));
                     push = true;
                 }
@@ -1773,9 +1778,11 @@ bool static ProcessHeadersMessage(CNode *pfrom, CConnman *connman, const std::ve
             }
         }
 
-        if (!pfrom->fDisconnect && IsOutboundDisconnectionCandidate(pfrom) && nodestate->pindexBestKnownBlock != nullptr) {
-            // If this is an outbound peer, check to see if we should protect
+        if (!pfrom->fDisconnect && IsOutboundDisconnectionCandidate(pfrom) && 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
+            // only consider setting m_protect for the full-relay peers.
             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;
@@ -1996,9 +2003,9 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
         // set nodes not capable of serving the complete blockchain history as "limited nodes"
         pfrom->m_limited_node = (!(nServices & NODE_NETWORK) && (nServices & NODE_NETWORK_LIMITED));
 
-        {
-            LOCK(pfrom->cs_filter);
-            pfrom->fRelayTxes = fRelay; // set to true after we get the first filter* message
+        if (pfrom->m_tx_relay != nullptr) {
+            LOCK(pfrom->m_tx_relay->cs_filter);
+            pfrom->m_tx_relay->fRelayTxes = fRelay; // set to true after we get the first filter* message
         }
 
         // Change version
@@ -2017,7 +2024,7 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
         UpdatePreferredDownload(pfrom, State(pfrom->GetId()));
         }
 
-        if (!pfrom->fInbound)
+        if (!pfrom->fInbound && pfrom->IsAddrRelayPeer())
         {
             // Advertise our address
             if (fListen && !::ChainstateActive().IsInitialBlockDownload())
@@ -2089,9 +2096,10 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
             // 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()) : ""));
+            LogPrintf("New outbound peer connected: version: %d, blocks=%d, peer=%d%s (%s)\n",
+                      pfrom->nVersion.load(), pfrom->nStartingHeight,
+                      pfrom->GetId(), (fLogIPs ? strprintf(", peeraddr=%s", pfrom->addr.ToString()) : ""),
+                      pfrom->m_tx_relay == nullptr ? "block-relay" : "full-relay");
         }
 
         if (pfrom->nVersion >= SENDHEADERS_VERSION) {
@@ -2132,6 +2140,9 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
         // Don't want addr from older versions unless seeding
         if (pfrom->nVersion < CADDR_TIME_VERSION && connman->GetAddressCount() > 1000)
             return true;
+        if (!pfrom->IsAddrRelayPeer()) {
+            return true;
+        }
         if (vAddr.size() > 1000)
         {
             LOCK(cs_main);
@@ -2215,7 +2226,9 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
             return false;
         }
 
-        bool fBlocksOnly = !g_relay_txes;
+        // We won't accept tx inv's if we're in blocks-only mode, or this is a
+        // block-relay-only peer
+        bool fBlocksOnly = !g_relay_txes || (pfrom->m_tx_relay == nullptr);
 
         // Allow whitelisted peers to send data other than blocks in blocks only mode if whitelistrelay is true
         if (pfrom->HasPermission(PF_RELAY))
@@ -2254,7 +2267,9 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
             {
                 pfrom->AddInventoryKnown(inv);
                 if (fBlocksOnly) {
-                    LogPrint(BCLog::NET, "transaction (%s) inv sent in violation of protocol peer=%d\n", inv.hash.ToString(), pfrom->GetId());
+                    LogPrint(BCLog::NET, "transaction (%s) inv sent in violation of protocol, disconnecting peer=%d\n", inv.hash.ToString(), pfrom->GetId());
+                    pfrom->fDisconnect = true;
+                    return true;
                 } else if (!fAlreadyHave && !fImporting && !fReindex && !::ChainstateActive().IsInitialBlockDownload()) {
                     RequestTx(State(pfrom->GetId()), inv.hash, current_time);
                 }
@@ -2471,9 +2486,11 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
     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 (!g_relay_txes && !pfrom->HasPermission(PF_RELAY))
+        // or if this peer is supposed to be a block-relay-only peer
+        if ((!g_relay_txes && !pfrom->HasPermission(PF_RELAY)) || (pfrom->m_tx_relay == nullptr))
         {
             LogPrint(BCLog::NET, "transaction sent in violation of protocol peer=%d\n", pfrom->GetId());
+            pfrom->fDisconnect = true;
             return true;
         }
 
@@ -2990,6 +3007,10 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
             LogPrint(BCLog::NET, "Ignoring \"getaddr\" from outbound connection. peer=%d\n", pfrom->GetId());
             return true;
         }
+        if (!pfrom->IsAddrRelayPeer()) {
+            LogPrint(BCLog::NET, "Ignoring \"getaddr\" from block-relay-only 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.
@@ -3031,8 +3052,10 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
             return true;
         }
 
-        LOCK(pfrom->cs_inventory);
-        pfrom->fSendMempool = true;
+        if (pfrom->m_tx_relay != nullptr) {
+            LOCK(pfrom->m_tx_relay->cs_tx_inventory);
+            pfrom->m_tx_relay->fSendMempool = true;
+        }
         return true;
     }
 
@@ -3123,12 +3146,12 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
             LOCK(cs_main);
             Misbehaving(pfrom->GetId(), 100);
         }
-        else
+        else if (pfrom->m_tx_relay != nullptr)
         {
-            LOCK(pfrom->cs_filter);
-            pfrom->pfilter.reset(new CBloomFilter(filter));
-            pfrom->pfilter->UpdateEmptyFull();
-            pfrom->fRelayTxes = true;
+            LOCK(pfrom->m_tx_relay->cs_filter);
+            pfrom->m_tx_relay->pfilter.reset(new CBloomFilter(filter));
+            pfrom->m_tx_relay->pfilter->UpdateEmptyFull();
+            pfrom->m_tx_relay->fRelayTxes = true;
         }
         return true;
     }
@@ -3142,10 +3165,10 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
         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 if (pfrom->m_tx_relay != nullptr) {
+            LOCK(pfrom->m_tx_relay->cs_filter);
+            if (pfrom->m_tx_relay->pfilter) {
+                pfrom->m_tx_relay->pfilter->insert(vData);
             } else {
                 bad = true;
             }
@@ -3158,11 +3181,14 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
     }
 
     if (strCommand == NetMsgType::FILTERCLEAR) {
-        LOCK(pfrom->cs_filter);
+        if (pfrom->m_tx_relay == nullptr) {
+            return true;
+        }
+        LOCK(pfrom->m_tx_relay->cs_filter);
         if (pfrom->GetLocalServices() & NODE_BLOOM) {
-            pfrom->pfilter.reset(new CBloomFilter());
+            pfrom->m_tx_relay->pfilter.reset(new CBloomFilter());
         }
-        pfrom->fRelayTxes = true;
+        pfrom->m_tx_relay->fRelayTxes = true;
         return true;
     }
 
@@ -3170,9 +3196,9 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
         CAmount newFeeFilter = 0;
         vRecv >> newFeeFilter;
         if (MoneyRange(newFeeFilter)) {
-            {
-                LOCK(pfrom->cs_feeFilter);
-                pfrom->minFeeFilter = newFeeFilter;
+            if (pfrom->m_tx_relay != nullptr) {
+                LOCK(pfrom->m_tx_relay->cs_feeFilter);
+                pfrom->m_tx_relay->minFeeFilter = newFeeFilter;
             }
             LogPrint(BCLog::NET, "received: feefilter of %s from peer=%d\n", CFeeRate(newFeeFilter).ToString(), pfrom->GetId());
         }
@@ -3449,6 +3475,8 @@ void PeerLogicValidation::EvictExtraOutboundPeers(int64_t time_in_seconds)
             if (state == nullptr) return; // shouldn't be possible, but just in case
             // Don't evict our protected peers
             if (state->m_chain_sync.m_protect) return;
+            // Don't evict our block-relay-only peers.
+            if (pnode->m_tx_relay == nullptr) return;
             if (state->m_last_block_announcement < oldest_block_announcement || (state->m_last_block_announcement == oldest_block_announcement && pnode->GetId() > worst_peer)) {
                 worst_peer = pnode->GetId();
                 oldest_block_announcement = state->m_last_block_announcement;
@@ -3576,7 +3604,7 @@ bool PeerLogicValidation::SendMessages(CNode* pto)
 
         // Address refresh broadcast
         int64_t nNow = GetTimeMicros();
-        if (!::ChainstateActive().IsInitialBlockDownload() && pto->nNextLocalAddrSend < nNow) {
+        if (pto->IsAddrRelayPeer() && !::ChainstateActive().IsInitialBlockDownload() && pto->nNextLocalAddrSend < nNow) {
             AdvertiseLocal(pto);
             pto->nNextLocalAddrSend = PoissonNextSend(nNow, AVG_LOCAL_ADDRESS_BROADCAST_INTERVAL);
         }
@@ -3584,7 +3612,7 @@ bool PeerLogicValidation::SendMessages(CNode* pto)
         //
         // Message: addr
         //
-        if (pto->nNextAddrSend < nNow) {
+        if (pto->IsAddrRelayPeer() && pto->nNextAddrSend < nNow) {
             pto->nNextAddrSend = PoissonNextSend(nNow, AVG_ADDRESS_BROADCAST_INTERVAL);
             std::vector<CAddress> vAddr;
             vAddr.reserve(pto->vAddrToSend.size());
@@ -3792,120 +3820,123 @@ bool PeerLogicValidation::SendMessages(CNode* pto)
             }
             pto->vInventoryBlockToSend.clear();
 
-            // Check whether periodic sends should happen
-            bool fSendTrickle = pto->HasPermission(PF_NOBAN);
-            if (pto->nNextInvSend < nNow) {
-                fSendTrickle = true;
-                if (pto->fInbound) {
-                    pto->nNextInvSend = connman->PoissonNextSendInbound(nNow, INVENTORY_BROADCAST_INTERVAL);
-                } else {
-                    // Use half the delay for outbound peers, as there is less privacy concern for them.
-                    pto->nNextInvSend = PoissonNextSend(nNow, INVENTORY_BROADCAST_INTERVAL >> 1);
+            if (pto->m_tx_relay != nullptr) {
+                LOCK(pto->m_tx_relay->cs_tx_inventory);
+                // Check whether periodic sends should happen
+                bool fSendTrickle = pto->HasPermission(PF_NOBAN);
+                if (pto->m_tx_relay->nNextInvSend < nNow) {
+                    fSendTrickle = true;
+                    if (pto->fInbound) {
+                        pto->m_tx_relay->nNextInvSend = connman->PoissonNextSendInbound(nNow, INVENTORY_BROADCAST_INTERVAL);
+                    } else {
+                        // Use half the delay for outbound peers, as there is less privacy concern for them.
+                        pto->m_tx_relay->nNextInvSend = PoissonNextSend(nNow, INVENTORY_BROADCAST_INTERVAL >> 1);
+                    }
                 }
-            }
-
-            // 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 = mempool.infoAll();
-                pto->fSendMempool = false;
-                CAmount filterrate = 0;
-                {
-                    LOCK(pto->cs_feeFilter);
-                    filterrate = pto->minFeeFilter;
+                // Time to send but the peer has requested we not relay transactions.
+                if (fSendTrickle) {
+                    LOCK(pto->m_tx_relay->cs_filter);
+                    if (!pto->m_tx_relay->fRelayTxes) pto->m_tx_relay->setInventoryTxToSend.clear();
                 }
 
-                LOCK(pto->cs_filter);
-
-                for (const auto& txinfo : vtxinfo) {
-                    const uint256& hash = txinfo.tx->GetHash();
-                    CInv inv(MSG_TX, hash);
-                    pto->setInventoryTxToSend.erase(hash);
-                    if (filterrate) {
-                        if (txinfo.feeRate.GetFeePerK() < filterrate)
-                            continue;
-                    }
-                    if (pto->pfilter) {
-                        if (!pto->pfilter->IsRelevantAndUpdate(*txinfo.tx)) continue;
+                // Respond to BIP35 mempool requests
+                if (fSendTrickle && pto->m_tx_relay->fSendMempool) {
+                    auto vtxinfo = mempool.infoAll();
+                    pto->m_tx_relay->fSendMempool = false;
+                    CAmount filterrate = 0;
+                    {
+                        LOCK(pto->m_tx_relay->cs_feeFilter);
+                        filterrate = pto->m_tx_relay->minFeeFilter;
                     }
-                    pto->filterInventoryKnown.insert(hash);
-                    vInv.push_back(inv);
-                    if (vInv.size() == MAX_INV_SZ) {
-                        connman->PushMessage(pto, msgMaker.Make(NetMsgType::INV, vInv));
-                        vInv.clear();
+
+                    LOCK(pto->m_tx_relay->cs_filter);
+
+                    for (const auto& txinfo : vtxinfo) {
+                        const uint256& hash = txinfo.tx->GetHash();
+                        CInv inv(MSG_TX, hash);
+                        pto->m_tx_relay->setInventoryTxToSend.erase(hash);
+                        if (filterrate) {
+                            if (txinfo.feeRate.GetFeePerK() < filterrate)
+                                continue;
+                        }
+                        if (pto->m_tx_relay->pfilter) {
+                            if (!pto->m_tx_relay->pfilter->IsRelevantAndUpdate(*txinfo.tx)) continue;
+                        }
+                        pto->m_tx_relay->filterInventoryKnown.insert(hash);
+                        vInv.push_back(inv);
+                        if (vInv.size() == MAX_INV_SZ) {
+                            connman->PushMessage(pto, msgMaker.Make(NetMsgType::INV, vInv));
+                            vInv.clear();
+                        }
                     }
+                    pto->m_tx_relay->timeLastMempoolReq = GetTime();
                 }
-                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);
-                }
-                CAmount filterrate = 0;
-                {
-                    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(&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) {
-                    // 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;
+                // Determine transactions to relay
+                if (fSendTrickle) {
+                    // Produce a vector with all candidates for sending
+                    std::vector<std::set<uint256>::iterator> vInvTx;
+                    vInvTx.reserve(pto->m_tx_relay->setInventoryTxToSend.size());
+                    for (std::set<uint256>::iterator it = pto->m_tx_relay->setInventoryTxToSend.begin(); it != pto->m_tx_relay->setInventoryTxToSend.end(); it++) {
+                        vInvTx.push_back(it);
                     }
-                    // Not in the mempool anymore? don't bother sending it.
-                    auto txinfo = mempool.info(hash);
-                    if (!txinfo.tx) {
-                        continue;
-                    }
-                    if (filterrate && txinfo.feeRate.GetFeePerK() < filterrate) {
-                        continue;
-                    }
-                    if (pto->pfilter && !pto->pfilter->IsRelevantAndUpdate(*txinfo.tx)) continue;
-                    // Send
-                    vInv.push_back(CInv(MSG_TX, hash));
-                    nRelayedTransactions++;
+                    CAmount filterrate = 0;
                     {
-                        // Expire old relay messages
-                        while (!vRelayExpiration.empty() && vRelayExpiration.front().first < nNow)
-                        {
-                            mapRelay.erase(vRelayExpiration.front().second);
-                            vRelayExpiration.pop_front();
+                        LOCK(pto->m_tx_relay->cs_feeFilter);
+                        filterrate = pto->m_tx_relay->minFeeFilter;
+                    }
+                    // Topologically and fee-rate sort the inventory we send for privacy and priority reasons.
+                    // A heap is used so that not all items need sorting if only a few are being sent.
+                    CompareInvMempoolOrder compareInvMempoolOrder(&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->m_tx_relay->cs_filter);
+                    while (!vInvTx.empty() && nRelayedTransactions < INVENTORY_BROADCAST_MAX) {
+                        // Fetch the top element from the heap
+                        std::pop_heap(vInvTx.begin(), vInvTx.end(), compareInvMempoolOrder);
+                        std::set<uint256>::iterator it = vInvTx.back();
+                        vInvTx.pop_back();
+                        uint256 hash = *it;
+                        // Remove it from the to-be-sent set
+                        pto->m_tx_relay->setInventoryTxToSend.erase(it);
+                        // Check if not in the filter already
+                        if (pto->m_tx_relay->filterInventoryKnown.contains(hash)) {
+                            continue;
                         }
+                        // Not in the mempool anymore? don't bother sending it.
+                        auto txinfo = mempool.info(hash);
+                        if (!txinfo.tx) {
+                            continue;
+                        }
+                        if (filterrate && txinfo.feeRate.GetFeePerK() < filterrate) {
+                            continue;
+                        }
+                        if (pto->m_tx_relay->pfilter && !pto->m_tx_relay->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));
+                            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->m_tx_relay->filterInventoryKnown.insert(hash);
                     }
-                    if (vInv.size() == MAX_INV_SZ) {
-                        connman->PushMessage(pto, msgMaker.Make(NetMsgType::INV, vInv));
-                        vInv.clear();
-                    }
-                    pto->filterInventoryKnown.insert(hash);
                 }
             }
         }
@@ -4066,27 +4097,27 @@ bool PeerLogicValidation::SendMessages(CNode* pto)
         // 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) &&
+        if (pto->m_tx_relay != nullptr && pto->nVersion >= FEEFILTER_VERSION && gArgs.GetBoolArg("-feefilter", DEFAULT_FEEFILTER) &&
             !pto->HasPermission(PF_FORCERELAY)) {
             CAmount currentFilter = mempool.GetMinFee(gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000).GetFeePerK();
             int64_t timeNow = GetTimeMicros();
-            if (timeNow > pto->nextSendTimeFeeFilter) {
+            if (timeNow > pto->m_tx_relay->nextSendTimeFeeFilter) {
                 static CFeeRate default_feerate(DEFAULT_MIN_RELAY_TX_FEE);
                 static FeeFilterRounder filterRounder(default_feerate);
                 CAmount filterToSend = filterRounder.round(currentFilter);
                 // We always have a fee filter of at least minRelayTxFee
                 filterToSend = std::max(filterToSend, ::minRelayTxFee.GetFeePerK());
-                if (filterToSend != pto->lastSentFeeFilter) {
+                if (filterToSend != pto->m_tx_relay->lastSentFeeFilter) {
                     connman->PushMessage(pto, msgMaker.Make(NetMsgType::FEEFILTER, filterToSend));
-                    pto->lastSentFeeFilter = filterToSend;
+                    pto->m_tx_relay->lastSentFeeFilter = filterToSend;
                 }
-                pto->nextSendTimeFeeFilter = PoissonNextSend(timeNow, AVG_FEEFILTER_BROADCAST_INTERVAL);
+                pto->m_tx_relay->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;
+            else if (timeNow + MAX_FEEFILTER_CHANGE_DELAY * 1000000 < pto->m_tx_relay->nextSendTimeFeeFilter &&
+                     (currentFilter < 3 * pto->m_tx_relay->lastSentFeeFilter / 4 || currentFilter > 4 * pto->m_tx_relay->lastSentFeeFilter / 3)) {
+                pto->m_tx_relay->nextSendTimeFeeFilter = timeNow + GetRandInt(MAX_FEEFILTER_CHANGE_DELAY) * 1000000;
             }
         }
     }