From 76568a3351418c878d30ba0373cf76988f93f90e Mon Sep 17 00:00:00 2001 From: John Newbery Date: Fri, 10 Jul 2020 16:29:57 +0100 Subject: [PATCH] [net processing] Move addr relay data and logic into net processing --- src/net.cpp | 4 - src/net.h | 56 -------------- src/net_processing.cpp | 168 +++++++++++++++++++++++++++-------------- src/test/fuzz/net.cpp | 22 ------ 4 files changed, 112 insertions(+), 138 deletions(-) diff --git a/src/net.cpp b/src/net.cpp index 1dcb141421..b0f4266765 100644 --- a/src/net.cpp +++ b/src/net.cpp @@ -2926,10 +2926,6 @@ CNode::CNode(NodeId idIn, ServiceFlags nLocalServicesIn, SOCKET hSocketIn, const m_tx_relay = std::make_unique(); } - if (RelayAddrsWithConn()) { - m_addr_known = std::make_unique(5000, 0.001); - } - for (const std::string &msg : getAllNetMessageTypes()) mapRecvBytesPerMsgCmd[msg] = 0; mapRecvBytesPerMsgCmd[NET_MESSAGE_COMMAND_OTHER] = 0; diff --git a/src/net.h b/src/net.h index cae22969ce..dc0d97372f 100644 --- a/src/net.h +++ b/src/net.h @@ -54,8 +54,6 @@ static const int TIMEOUT_INTERVAL = 20 * 60; static constexpr auto FEELER_INTERVAL = 2min; /** Run the extra block-relay-only connection loop once every 5 minutes. **/ static constexpr auto EXTRA_BLOCK_RELAY_ONLY_PEER_INTERVAL = 5min; -/** The maximum number of addresses from our addrman to return in response to a getaddr message. */ -static constexpr size_t MAX_ADDR_TO_SEND = 1000; /** Maximum length of incoming protocol messages (no message over 4 MB is currently acceptable). */ static const unsigned int MAX_PROTOCOL_MESSAGE_LENGTH = 4 * 1000 * 1000; /** Maximum length of the user agent string in `version` message */ @@ -447,17 +445,11 @@ public: } bool fClient{false}; // set by version message bool m_limited_node{false}; //after BIP159, set by version message - /** - * Whether the peer has signaled support for receiving ADDRv2 (BIP155) - * messages, implying a preference to receive ADDRv2 instead of ADDR ones. - */ - std::atomic_bool m_wants_addrv2{false}; /** fSuccessfullyConnected is set to true on receiving VERACK from the peer. */ std::atomic_bool fSuccessfullyConnected{false}; // Setting fDisconnect to true will cause the node to be disconnected the // next time DisconnectNodes() runs std::atomic_bool fDisconnect{false}; - bool fSentAddr{false}; CSemaphoreGrant grantOutbound; std::atomic nRefCount{0}; @@ -504,15 +496,6 @@ public: return m_conn_type == ConnectionType::INBOUND; } - /* Whether we send addr messages over this connection */ - bool RelayAddrsWithConn() const - { - // Don't relay addr messages to peers that we connect to as block-relay-only - // peers (to prevent adversaries from inferring these links from addr - // traffic). - return m_conn_type != ConnectionType::BLOCK_RELAY; - } - bool ExpectServicesFromConn() const { switch (m_conn_type) { case ConnectionType::INBOUND: @@ -545,14 +528,6 @@ public: // Peer selected us as (compact blocks) high-bandwidth peer (BIP152) std::atomic m_bip152_highbandwidth_from{false}; - // flood relay - std::vector vAddrToSend; - std::unique_ptr m_addr_known{nullptr}; - bool fGetAddr{false}; - Mutex m_addr_send_times_mutex; - std::chrono::microseconds m_next_addr_send GUARDED_BY(m_addr_send_times_mutex){0}; - std::chrono::microseconds m_next_local_addr_send GUARDED_BY(m_addr_send_times_mutex){0}; - struct TxRelay { mutable RecursiveMutex cs_filter; // We use fRelayTxes for two purposes - @@ -657,37 +632,6 @@ public: nRefCount--; } - void AddAddressKnown(const CAddress& _addr) - { - assert(m_addr_known); - m_addr_known->insert(_addr.GetKey()); - } - - /** - * Whether the peer supports the address. For example, a peer that does not - * implement BIP155 cannot receive Tor v3 addresses because it requires - * ADDRv2 (BIP155) encoding. - */ - bool IsAddrCompatible(const CAddress& addr) const - { - return m_wants_addrv2 || addr.IsAddrV1Compatible(); - } - - void PushAddress(const CAddress& _addr, FastRandomContext &insecure_rand) - { - // Known checking here is only to save space from duplicates. - // SendMessages will filter it again for knowns that were added - // after addresses were pushed. - assert(m_addr_known); - if (_addr.IsValid() && !m_addr_known->contains(_addr.GetKey()) && IsAddrCompatible(_addr)) { - if (vAddrToSend.size() >= MAX_ADDR_TO_SEND) { - vAddrToSend[insecure_rand.randrange(vAddrToSend.size())] = _addr; - } else { - vAddrToSend.push_back(_addr); - } - } - } - void AddKnownTx(const uint256& hash) { if (m_tx_relay != nullptr) { diff --git a/src/net_processing.cpp b/src/net_processing.cpp index 7ebd28b696..543f58b5e5 100644 --- a/src/net_processing.cpp +++ b/src/net_processing.cpp @@ -150,6 +150,8 @@ static constexpr uint32_t MAX_GETCFILTERS_SIZE = 1000; static constexpr uint32_t MAX_GETCFHEADERS_SIZE = 2000; /** the maximum percentage of addresses from our addrman to return in response to a getaddr message. */ static constexpr size_t MAX_PCT_ADDR_TO_SEND = 23; +/** The maximum number of address records permitted in an ADDR message. */ +static constexpr size_t MAX_ADDR_TO_SEND{1000}; // Internal stuff namespace { @@ -210,6 +212,25 @@ struct Peer { /** Whether a ping has been requested by the user */ std::atomic m_ping_queued{false}; + /** A vector of addresses to send to the peer, limited to MAX_ADDR_TO_SEND. */ + std::vector vAddrToSend; + /** Probabilistic filter of addresses that this peer already knows. + * Used to avoid relaying addresses to this peer more than once. */ + const std::unique_ptr m_addr_known; + /** Whether a getaddr request to this peer is outstanding. */ + bool fGetAddr{false}; + /** Guards address sending timers. */ + mutable Mutex m_addr_send_times_mutex; + /** Time point to send the next ADDR message to this peer. */ + std::chrono::microseconds m_next_addr_send GUARDED_BY(m_addr_send_times_mutex){0}; + /** Time point to possibly re-announce our local address to this peer. */ + std::chrono::microseconds m_next_local_addr_send GUARDED_BY(m_addr_send_times_mutex){0}; + /** Whether the peer has signaled support for receiving ADDRv2 (BIP155) + * messages, indicating a preference to receive ADDRv2 instead of ADDR ones. */ + std::atomic_bool m_wants_addrv2{false}; + /** Whether this peer has already sent us a getaddr message. */ + bool fSentAddr{false}; + /** Set of txids to reconsider once their parent transactions have been accepted **/ std::set m_orphan_work_set GUARDED_BY(g_cs_orphans); @@ -218,7 +239,10 @@ struct Peer { /** Work queue of items requested by this peer **/ std::deque m_getdata_requests GUARDED_BY(m_getdata_requests_mutex); - explicit Peer(NodeId id) : m_id(id) {} + explicit Peer(NodeId id, bool addr_relay) + : m_id(id) + , m_addr_known{addr_relay ? std::make_unique(5000, 0.001) : nullptr} + {} }; using PeerRef = std::shared_ptr; @@ -324,7 +348,7 @@ private: void MaybeSendPing(CNode& node_to, Peer& peer, std::chrono::microseconds now); /** Send `addr` messages on a regular schedule. */ - void MaybeSendAddr(CNode& node, std::chrono::microseconds current_time); + void MaybeSendAddr(CNode& node, Peer& peer, std::chrono::microseconds current_time); /** Relay (gossip) an address to a few randomly chosen nodes. * @@ -626,6 +650,42 @@ static CNodeState *State(NodeId pnode) EXCLUSIVE_LOCKS_REQUIRED(cs_main) { return &it->second; } +static bool RelayAddrsWithPeer(const Peer& peer) +{ + return peer.m_addr_known != nullptr; +} + +/** + * Whether the peer supports the address. For example, a peer that does not + * implement BIP155 cannot receive Tor v3 addresses because it requires + * ADDRv2 (BIP155) encoding. + */ +static bool IsAddrCompatible(const Peer& peer, const CAddress& addr) +{ + return peer.m_wants_addrv2 || addr.IsAddrV1Compatible(); +} + +static void AddAddressKnown(Peer& peer, const CAddress& addr) +{ + assert(peer.m_addr_known); + peer.m_addr_known->insert(addr.GetKey()); +} + +static void PushAddress(Peer& peer, const CAddress& addr, FastRandomContext& insecure_rand) +{ + // Known checking here is only to save space from duplicates. + // Before sending, we'll filter it again for known addresses that were + // added after addresses were pushed. + assert(peer.m_addr_known); + if (addr.IsValid() && !peer.m_addr_known->contains(addr.GetKey()) && IsAddrCompatible(peer, addr)) { + if (peer.vAddrToSend.size() >= MAX_ADDR_TO_SEND) { + peer.vAddrToSend[insecure_rand.randrange(peer.vAddrToSend.size())] = addr; + } else { + peer.vAddrToSend.push_back(addr); + } + } +} + static void UpdatePreferredDownload(const CNode& node, CNodeState* state) EXCLUSIVE_LOCKS_REQUIRED(cs_main) { nPreferredDownload -= state->fPreferredDownload; @@ -954,7 +1014,9 @@ void PeerManagerImpl::InitializeNode(CNode *pnode) assert(m_txrequest.Count(nodeid) == 0); } { - PeerRef peer = std::make_shared(nodeid); + // Addr relay is disabled for outbound block-relay-only peers to + // prevent adversaries from inferring these links from addr traffic. + PeerRef peer = std::make_shared(nodeid, /* addr_relay = */ !pnode->IsBlockOnlyConn()); LOCK(m_peer_mutex); m_peer_map.emplace_hint(m_peer_map.end(), nodeid, std::move(peer)); } @@ -1514,29 +1576,27 @@ void PeerManagerImpl::RelayAddress(NodeId originator, // Relay reachable addresses to 2 peers. Unreachable addresses are relayed randomly to 1 or 2 peers. unsigned int nRelayNodes = (fReachable || (hasher.Finalize() & 1)) ? 2 : 1; - std::array,2> best{{{0, nullptr}, {0, nullptr}}}; + std::array, 2> best{{{0, nullptr}, {0, nullptr}}}; assert(nRelayNodes <= best.size()); - auto sortfunc = [&best, &hasher, nRelayNodes, originator, &addr](CNode* pnode) { - if (pnode->RelayAddrsWithConn() && pnode->GetId() != originator && pnode->IsAddrCompatible(addr)) { - uint64_t hashKey = CSipHasher(hasher).Write(pnode->GetId()).Finalize(); + LOCK(m_peer_mutex); + + for (auto& [id, peer] : m_peer_map) { + if (RelayAddrsWithPeer(*peer) && id != originator && IsAddrCompatible(*peer, addr)) { + uint64_t hashKey = CSipHasher(hasher).Write(id).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); + best[i] = std::make_pair(hashKey, peer.get()); 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); - } - }; - - m_connman.ForEachNodeThen(std::move(sortfunc), std::move(pushfunc)); + for (unsigned int i = 0; i < nRelayNodes && best[i].first != 0; i++) { + PushAddress(*best[i].second, addr, insecure_rand); + } } void PeerManagerImpl::ProcessGetBlockData(CNode& pfrom, Peer& peer, const CInv& inv) @@ -2457,17 +2517,17 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type, if (addr.IsRoutable()) { LogPrint(BCLog::NET, "ProcessMessages: advertising address %s\n", addr.ToString()); - pfrom.PushAddress(addr, insecure_rand); + PushAddress(*peer, 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); + PushAddress(*peer, addr, insecure_rand); } } // Get recent addresses m_connman.PushMessage(&pfrom, CNetMsgMaker(greatest_common_version).Make(NetMsgType::GETADDR)); - pfrom.fGetAddr = true; + peer->fGetAddr = true; } if (!pfrom.IsInboundConn()) { @@ -2626,7 +2686,7 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type, pfrom.fDisconnect = true; return; } - pfrom.m_wants_addrv2 = true; + peer->m_wants_addrv2 = true; return; } @@ -2648,7 +2708,7 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type, s >> vAddr; - if (!pfrom.RelayAddrsWithConn()) { + if (!RelayAddrsWithPeer(*peer)) { LogPrint(BCLog::NET, "ignoring %s message from %s peer=%d\n", msg_type, pfrom.ConnectionTypeAsString(), pfrom.GetId()); return; } @@ -2675,14 +2735,13 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type, if (addr.nTime <= 100000000 || addr.nTime > nNow + 10 * 60) addr.nTime = nNow - 5 * 24 * 60 * 60; - pfrom.AddAddressKnown(addr); + AddAddressKnown(*peer, addr); if (m_banman && (m_banman->IsDiscouraged(addr) || m_banman->IsBanned(addr))) { // Do not process banned/discouraged addresses beyond remembering we received them continue; } bool fReachable = IsReachable(addr); - if (addr.nTime > nSince && !pfrom.fGetAddr && vAddr.size() <= 10 && addr.IsRoutable()) - { + if (addr.nTime > nSince && !peer->fGetAddr && vAddr.size() <= 10 && addr.IsRoutable()) { // Relay to a limited number of other nodes RelayAddress(pfrom.GetId(), addr, fReachable); } @@ -2691,8 +2750,7 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type, vAddrOk.push_back(addr); } m_addrman.Add(vAddrOk, pfrom.addr, 2 * 60 * 60); - if (vAddr.size() < 1000) - pfrom.fGetAddr = false; + if (vAddr.size() < 1000) peer->fGetAddr = false; if (pfrom.IsAddrFetchConn()) { LogPrint(BCLog::NET, "addrfetch connection completed peer=%d; disconnecting\n", pfrom.GetId()); pfrom.fDisconnect = true; @@ -3573,14 +3631,14 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type, } // Only send one GetAddr response per connection to reduce resource waste - // and discourage addr stamping of INV announcements. - if (pfrom.fSentAddr) { + // and discourage addr stamping of INV announcements. + if (peer->fSentAddr) { LogPrint(BCLog::NET, "Ignoring repeated \"getaddr\". peer=%d\n", pfrom.GetId()); return; } - pfrom.fSentAddr = true; + peer->fSentAddr = true; - pfrom.vAddrToSend.clear(); + peer->vAddrToSend.clear(); std::vector vAddr; if (pfrom.HasPermission(PF_ADDR)) { vAddr = m_connman.GetAddresses(MAX_ADDR_TO_SEND, MAX_PCT_ADDR_TO_SEND); @@ -3589,7 +3647,7 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type, } FastRandomContext insecure_rand; for (const CAddress &addr : vAddr) { - pfrom.PushAddress(addr, insecure_rand); + PushAddress(*peer, addr, insecure_rand); } return; } @@ -4147,72 +4205,70 @@ void PeerManagerImpl::MaybeSendPing(CNode& node_to, Peer& peer, std::chrono::mic } } -void PeerManagerImpl::MaybeSendAddr(CNode& node, std::chrono::microseconds current_time) +void PeerManagerImpl::MaybeSendAddr(CNode& node, Peer& peer, std::chrono::microseconds current_time) { // Nothing to do for non-address-relay peers - if (!node.RelayAddrsWithConn()) return; - - assert(node.m_addr_known); + if (!RelayAddrsWithPeer(peer)) return; - LOCK(node.m_addr_send_times_mutex); + LOCK(peer.m_addr_send_times_mutex); // Periodically advertise our local address to the peer. if (fListen && !m_chainman.ActiveChainstate().IsInitialBlockDownload() && - node.m_next_local_addr_send < current_time) { + peer.m_next_local_addr_send < current_time) { // If we've sent before, clear the bloom filter for the peer, so that our // self-announcement will actually go out. // This might be unnecessary if the bloom filter has already rolled // over since our last self-announcement, but there is only a small // bandwidth cost that we can incur by doing this (which happens // once a day on average). - if (node.m_next_local_addr_send != 0us) { - node.m_addr_known->reset(); + if (peer.m_next_local_addr_send != 0us) { + peer.m_addr_known->reset(); } if (std::optional local_addr = GetLocalAddrForPeer(&node)) { FastRandomContext insecure_rand; - node.PushAddress(*local_addr, insecure_rand); + PushAddress(peer, *local_addr, insecure_rand); } - node.m_next_local_addr_send = PoissonNextSend(current_time, AVG_LOCAL_ADDRESS_BROADCAST_INTERVAL); + peer.m_next_local_addr_send = PoissonNextSend(current_time, AVG_LOCAL_ADDRESS_BROADCAST_INTERVAL); } // We sent an `addr` message to this peer recently. Nothing more to do. - if (current_time <= node.m_next_addr_send) return; + if (current_time <= peer.m_next_addr_send) return; - node.m_next_addr_send = PoissonNextSend(current_time, AVG_ADDRESS_BROADCAST_INTERVAL); + peer.m_next_addr_send = PoissonNextSend(current_time, AVG_ADDRESS_BROADCAST_INTERVAL); - if (!Assume(node.vAddrToSend.size() <= MAX_ADDR_TO_SEND)) { + if (!Assume(peer.vAddrToSend.size() <= MAX_ADDR_TO_SEND)) { // Should be impossible since we always check size before adding to // vAddrToSend. Recover by trimming the vector. - node.vAddrToSend.resize(MAX_ADDR_TO_SEND); + peer.vAddrToSend.resize(MAX_ADDR_TO_SEND); } // Remove addr records that the peer already knows about, and add new // addrs to the m_addr_known filter on the same pass. - auto addr_already_known = [&node](const CAddress& addr) { - bool ret = node.m_addr_known->contains(addr.GetKey()); - if (!ret) node.m_addr_known->insert(addr.GetKey()); + auto addr_already_known = [&peer](const CAddress& addr) { + bool ret = peer.m_addr_known->contains(addr.GetKey()); + if (!ret) peer.m_addr_known->insert(addr.GetKey()); return ret; }; - node.vAddrToSend.erase(std::remove_if(node.vAddrToSend.begin(), node.vAddrToSend.end(), addr_already_known), - node.vAddrToSend.end()); + peer.vAddrToSend.erase(std::remove_if(peer.vAddrToSend.begin(), peer.vAddrToSend.end(), addr_already_known), + peer.vAddrToSend.end()); // No addr messages to send - if (node.vAddrToSend.empty()) return; + if (peer.vAddrToSend.empty()) return; const char* msg_type; int make_flags; - if (node.m_wants_addrv2) { + if (peer.m_wants_addrv2) { msg_type = NetMsgType::ADDRV2; make_flags = ADDRV2_FORMAT; } else { msg_type = NetMsgType::ADDR; make_flags = 0; } - m_connman.PushMessage(&node, CNetMsgMaker(node.GetCommonVersion()).Make(make_flags, msg_type, node.vAddrToSend)); - node.vAddrToSend.clear(); + m_connman.PushMessage(&node, CNetMsgMaker(node.GetCommonVersion()).Make(make_flags, msg_type, peer.vAddrToSend)); + peer.vAddrToSend.clear(); // we only send the big addr message once - if (node.vAddrToSend.capacity() > 40) { - node.vAddrToSend.shrink_to_fit(); + if (peer.vAddrToSend.capacity() > 40) { + peer.vAddrToSend.shrink_to_fit(); } } @@ -4261,7 +4317,7 @@ bool PeerManagerImpl::SendMessages(CNode* pto) // MaybeSendPing may have marked peer for disconnection if (pto->fDisconnect) return true; - MaybeSendAddr(*pto, current_time); + MaybeSendAddr(*pto, *peer, current_time); { LOCK(cs_main); diff --git a/src/test/fuzz/net.cpp b/src/test/fuzz/net.cpp index 272f6415a9..20d8581312 100644 --- a/src/test/fuzz/net.cpp +++ b/src/test/fuzz/net.cpp @@ -57,27 +57,6 @@ FUZZ_TARGET_INIT(net, initialize_net) node.Release(); } }, - [&] { - if (node.m_addr_known == nullptr) { - return; - } - const std::optional addr_opt = ConsumeDeserializable(fuzzed_data_provider); - if (!addr_opt) { - return; - } - node.AddAddressKnown(*addr_opt); - }, - [&] { - if (node.m_addr_known == nullptr) { - return; - } - const std::optional addr_opt = ConsumeDeserializable(fuzzed_data_provider); - if (!addr_opt) { - return; - } - FastRandomContext fast_random_context{ConsumeUInt256(fuzzed_data_provider)}; - node.PushAddress(*addr_opt, fast_random_context); - }, [&] { const std::optional inv_opt = ConsumeDeserializable(fuzzed_data_provider); if (!inv_opt) { @@ -110,7 +89,6 @@ FUZZ_TARGET_INIT(net, initialize_net) const int ref_count = node.GetRefCount(); assert(ref_count >= 0); (void)node.GetCommonVersion(); - (void)node.RelayAddrsWithConn(); const NetPermissionFlags net_permission_flags = ConsumeWeakEnum(fuzzed_data_provider, ALL_NET_PERMISSION_FLAGS); (void)node.HasPermission(net_permission_flags);