denialofservice_tests.cpp
1 // Copyright (c) 2011-present The Bitcoin Core developers 2 // Distributed under the MIT software license, see the accompanying 3 // file COPYING or http://www.opensource.org/licenses/mit-license.php. 4 5 // Unit tests for denial-of-service detection/prevention code 6 7 #include <banman.h> 8 #include <chainparams.h> 9 #include <common/args.h> 10 #include <net.h> 11 #include <net_processing.h> 12 #include <pubkey.h> 13 #include <script/sign.h> 14 #include <script/signingprovider.h> 15 #include <serialize.h> 16 #include <test/util/net.h> 17 #include <test/util/random.h> 18 #include <test/util/setup_common.h> 19 #include <test/util/time.h> 20 #include <util/string.h> 21 #include <util/time.h> 22 #include <validation.h> 23 24 #include <array> 25 #include <cstdint> 26 27 #include <boost/test/unit_test.hpp> 28 29 static CService ip(uint32_t i) 30 { 31 struct in_addr s; 32 s.s_addr = i; 33 return CService(CNetAddr(s), Params().GetDefaultPort()); 34 } 35 36 BOOST_FIXTURE_TEST_SUITE(denialofservice_tests, TestingSetup) 37 38 // Test eviction of an outbound peer whose chain never advances 39 // Mock a node connection, and use mocktime to simulate a peer 40 // which never sends any headers messages. PeerLogic should 41 // decide to evict that outbound peer, after the appropriate timeouts. 42 // Note that we protect 4 outbound nodes from being subject to 43 // this logic; this test takes advantage of that protection only 44 // being applied to nodes which send headers with sufficient 45 // work. 46 BOOST_AUTO_TEST_CASE(outbound_slow_chain_eviction) 47 { 48 LOCK(NetEventsInterface::g_msgproc_mutex); 49 50 ConnmanTestMsg& connman = static_cast<ConnmanTestMsg&>(*m_node.connman); 51 // Disable inactivity checks for this test to avoid interference 52 connman.SetPeerConnectTimeout(99999s); 53 PeerManager& peerman = *m_node.peerman; 54 55 // Mock an outbound peer 56 CAddress addr1(ip(0xa0b0c001), NODE_NONE); 57 NodeId id{0}; 58 CNode dummyNode1{id++, 59 /*sock=*/nullptr, 60 addr1, 61 /*nKeyedNetGroupIn=*/0, 62 /*nLocalHostNonceIn=*/0, 63 CAddress(), 64 /*addrNameIn=*/"", 65 ConnectionType::OUTBOUND_FULL_RELAY, 66 /*inbound_onion=*/false, 67 /*network_key=*/0}; 68 69 connman.Handshake( 70 /*node=*/dummyNode1, 71 /*successfully_connected=*/true, 72 /*remote_services=*/ServiceFlags(NODE_NETWORK | NODE_WITNESS), 73 /*local_services=*/ServiceFlags(NODE_NETWORK | NODE_WITNESS), 74 /*version=*/PROTOCOL_VERSION, 75 /*relay_txs=*/true); 76 77 // This test requires that we have a chain with non-zero work. 78 { 79 LOCK(cs_main); 80 BOOST_CHECK(m_node.chainman->ActiveChain().Tip() != nullptr); 81 BOOST_CHECK(m_node.chainman->ActiveChain().Tip()->nChainWork > 0); 82 } 83 84 // Test starts here 85 BOOST_CHECK(peerman.SendMessages(dummyNode1)); // should result in getheaders 86 87 { 88 LOCK(dummyNode1.cs_vSend); 89 const auto& [to_send, _more, _msg_type] = dummyNode1.m_transport->GetBytesToSend(false); 90 BOOST_CHECK(!to_send.empty()); 91 } 92 connman.FlushSendBuffer(dummyNode1); 93 94 NodeClockContext clock_ctx{}; 95 clock_ctx += 21min; 96 97 BOOST_CHECK(peerman.SendMessages(dummyNode1)); // should result in getheaders 98 { 99 LOCK(dummyNode1.cs_vSend); 100 const auto& [to_send, _more, _msg_type] = dummyNode1.m_transport->GetBytesToSend(false); 101 BOOST_CHECK(!to_send.empty()); 102 } 103 104 clock_ctx += 3min; 105 BOOST_CHECK(peerman.SendMessages(dummyNode1)); // should result in disconnect 106 BOOST_CHECK(dummyNode1.fDisconnect == true); 107 108 peerman.FinalizeNode(dummyNode1); 109 } 110 111 struct OutboundTest : TestingSetup { 112 void AddRandomOutboundPeer(NodeId& id, std::vector<CNode*>& vNodes, PeerManager& peerLogic, ConnmanTestMsg& connman, ConnectionType connType, bool onion_peer = false) 113 { 114 CAddress addr; 115 116 if (onion_peer) { 117 auto tor_addr{m_rng.randbytes(ADDR_TORV3_SIZE)}; 118 BOOST_REQUIRE(addr.SetSpecial(OnionToString(tor_addr))); 119 } 120 121 while (!addr.IsRoutable()) { 122 addr = CAddress(ip(m_rng.randbits(32)), NODE_NONE); 123 } 124 125 vNodes.emplace_back(new CNode{id++, 126 /*sock=*/nullptr, 127 addr, 128 /*nKeyedNetGroupIn=*/0, 129 /*nLocalHostNonceIn=*/0, 130 CAddress(), 131 /*addrNameIn=*/"", 132 connType, 133 /*inbound_onion=*/false, 134 /*network_key=*/0}); 135 CNode &node = *vNodes.back(); 136 node.SetCommonVersion(PROTOCOL_VERSION); 137 138 peerLogic.InitializeNode(node, ServiceFlags(NODE_NETWORK | NODE_WITNESS)); 139 node.fSuccessfullyConnected = true; 140 141 connman.AddTestNode(node); 142 } 143 }; // struct OutboundTest 144 145 BOOST_FIXTURE_TEST_CASE(stale_tip_peer_management, OutboundTest) 146 { 147 NodeId id{0}; 148 auto connman = std::make_unique<ConnmanTestMsg>(0x1337, 0x1337, *m_node.addrman, *m_node.netgroupman, Params()); 149 auto peerLogic = PeerManager::make(*connman, *m_node.addrman, nullptr, *m_node.chainman, *m_node.mempool, *m_node.warnings, {}); 150 151 constexpr int max_outbound_full_relay = MAX_OUTBOUND_FULL_RELAY_CONNECTIONS; 152 CConnman::Options options; 153 options.m_max_automatic_connections = DEFAULT_MAX_PEER_CONNECTIONS; 154 155 const auto time_init{Now<NodeSeconds>()}; 156 NodeClockContext clock_ctx{time_init}; 157 const auto delta{3 * std::chrono::seconds{m_node.chainman->GetConsensus().nPowTargetSpacing} + 1s}; 158 connman->Init(options); 159 std::vector<CNode *> vNodes; 160 161 // Mock some outbound peers 162 for (int i = 0; i < max_outbound_full_relay; ++i) { 163 AddRandomOutboundPeer(id, vNodes, *peerLogic, *connman, ConnectionType::OUTBOUND_FULL_RELAY); 164 } 165 166 peerLogic->CheckForStaleTipAndEvictPeers(); 167 168 // No nodes should be marked for disconnection while we have no extra peers 169 for (const CNode *node : vNodes) { 170 BOOST_CHECK(node->fDisconnect == false); 171 } 172 173 clock_ctx += delta; 174 175 // Now tip should definitely be stale, and we should look for an extra 176 // outbound peer 177 peerLogic->CheckForStaleTipAndEvictPeers(); 178 BOOST_CHECK(connman->GetTryNewOutboundPeer()); 179 180 // Still no peers should be marked for disconnection 181 for (const CNode *node : vNodes) { 182 BOOST_CHECK(node->fDisconnect == false); 183 } 184 185 // If we add one more peer, something should get marked for eviction 186 // on the next check (since we're mocking the time to be in the future, the 187 // required time connected check should be satisfied). 188 clock_ctx.set(time_init); 189 AddRandomOutboundPeer(id, vNodes, *peerLogic, *connman, ConnectionType::OUTBOUND_FULL_RELAY); 190 clock_ctx += delta; 191 192 peerLogic->CheckForStaleTipAndEvictPeers(); 193 for (int i = 0; i < max_outbound_full_relay; ++i) { 194 BOOST_CHECK(vNodes[i]->fDisconnect == false); 195 } 196 // Last added node should get marked for eviction 197 BOOST_CHECK(vNodes.back()->fDisconnect == true); 198 199 vNodes.back()->fDisconnect = false; 200 201 // Update the last announced block time for the last 202 // peer, and check that the next newest node gets evicted. 203 peerLogic->UpdateLastBlockAnnounceTime(vNodes.back()->GetId(), GetTime()); 204 205 peerLogic->CheckForStaleTipAndEvictPeers(); 206 for (int i = 0; i < max_outbound_full_relay - 1; ++i) { 207 BOOST_CHECK(vNodes[i]->fDisconnect == false); 208 } 209 BOOST_CHECK(vNodes[max_outbound_full_relay-1]->fDisconnect == true); 210 BOOST_CHECK(vNodes.back()->fDisconnect == false); 211 212 vNodes[max_outbound_full_relay - 1]->fDisconnect = false; 213 214 // Add an onion peer, that will be protected because it is the only one for 215 // its network, so another peer gets disconnected instead. 216 clock_ctx.set(time_init); 217 AddRandomOutboundPeer(id, vNodes, *peerLogic, *connman, ConnectionType::OUTBOUND_FULL_RELAY, /*onion_peer=*/true); 218 clock_ctx += delta; 219 peerLogic->CheckForStaleTipAndEvictPeers(); 220 221 for (int i = 0; i < max_outbound_full_relay - 2; ++i) { 222 BOOST_CHECK(vNodes[i]->fDisconnect == false); 223 } 224 BOOST_CHECK(vNodes[max_outbound_full_relay - 2]->fDisconnect == false); 225 BOOST_CHECK(vNodes[max_outbound_full_relay - 1]->fDisconnect == true); 226 BOOST_CHECK(vNodes[max_outbound_full_relay]->fDisconnect == false); 227 228 // Add a second onion peer which won't be protected 229 clock_ctx.set(time_init); 230 AddRandomOutboundPeer(id, vNodes, *peerLogic, *connman, ConnectionType::OUTBOUND_FULL_RELAY, /*onion_peer=*/true); 231 clock_ctx += delta; 232 peerLogic->CheckForStaleTipAndEvictPeers(); 233 234 BOOST_CHECK(vNodes.back()->fDisconnect == true); 235 236 for (const CNode *node : vNodes) { 237 peerLogic->FinalizeNode(*node); 238 } 239 240 connman->ClearTestNodes(); 241 } 242 243 BOOST_FIXTURE_TEST_CASE(block_relay_only_eviction, OutboundTest) 244 { 245 NodeId id{0}; 246 auto connman = std::make_unique<ConnmanTestMsg>(0x1337, 0x1337, *m_node.addrman, *m_node.netgroupman, Params()); 247 auto peerLogic = PeerManager::make(*connman, *m_node.addrman, nullptr, *m_node.chainman, *m_node.mempool, *m_node.warnings, {}); 248 249 constexpr int max_outbound_block_relay{MAX_BLOCK_RELAY_ONLY_CONNECTIONS}; 250 constexpr auto MINIMUM_CONNECT_TIME{30s}; 251 CConnman::Options options; 252 options.m_max_automatic_connections = DEFAULT_MAX_PEER_CONNECTIONS; 253 254 connman->Init(options); 255 std::vector<CNode*> vNodes; 256 257 // Add block-relay-only peers up to the limit 258 for (int i = 0; i < max_outbound_block_relay; ++i) { 259 AddRandomOutboundPeer(id, vNodes, *peerLogic, *connman, ConnectionType::BLOCK_RELAY); 260 } 261 peerLogic->CheckForStaleTipAndEvictPeers(); 262 263 for (int i = 0; i < max_outbound_block_relay; ++i) { 264 BOOST_CHECK(vNodes[i]->fDisconnect == false); 265 } 266 267 // Add an extra block-relay-only peer breaking the limit (mocks logic in ThreadOpenConnections) 268 AddRandomOutboundPeer(id, vNodes, *peerLogic, *connman, ConnectionType::BLOCK_RELAY); 269 peerLogic->CheckForStaleTipAndEvictPeers(); 270 271 // The extra peer should only get marked for eviction after MINIMUM_CONNECT_TIME 272 for (int i = 0; i < max_outbound_block_relay; ++i) { 273 BOOST_CHECK(vNodes[i]->fDisconnect == false); 274 } 275 BOOST_CHECK(vNodes.back()->fDisconnect == false); 276 277 NodeClockContext clock_ctx{}; 278 clock_ctx += MINIMUM_CONNECT_TIME; 279 peerLogic->CheckForStaleTipAndEvictPeers(); 280 for (int i = 0; i < max_outbound_block_relay; ++i) { 281 BOOST_CHECK(vNodes[i]->fDisconnect == false); 282 } 283 BOOST_CHECK(vNodes.back()->fDisconnect == true); 284 285 // Update the last block time for the extra peer, 286 // and check that the next youngest peer gets evicted. 287 vNodes.back()->fDisconnect = false; 288 vNodes.back()->m_last_block_time = GetTime<std::chrono::seconds>(); 289 290 peerLogic->CheckForStaleTipAndEvictPeers(); 291 for (int i = 0; i < max_outbound_block_relay - 1; ++i) { 292 BOOST_CHECK(vNodes[i]->fDisconnect == false); 293 } 294 BOOST_CHECK(vNodes[max_outbound_block_relay - 1]->fDisconnect == true); 295 BOOST_CHECK(vNodes.back()->fDisconnect == false); 296 297 for (const CNode* node : vNodes) { 298 peerLogic->FinalizeNode(*node); 299 } 300 connman->ClearTestNodes(); 301 } 302 303 BOOST_AUTO_TEST_CASE(peer_discouragement) 304 { 305 LOCK(NetEventsInterface::g_msgproc_mutex); 306 307 auto banman = std::make_unique<BanMan>(m_args.GetDataDirBase() / "banlist", nullptr, DEFAULT_MISBEHAVING_BANTIME); 308 auto connman = std::make_unique<ConnmanTestMsg>(0x1337, 0x1337, *m_node.addrman, *m_node.netgroupman, Params()); 309 auto peerLogic = PeerManager::make(*connman, *m_node.addrman, banman.get(), *m_node.chainman, *m_node.mempool, *m_node.warnings, {}); 310 311 CNetAddr tor_netaddr; 312 BOOST_REQUIRE( 313 tor_netaddr.SetSpecial("pg6mmjiyjmcrsslvykfwnntlaru7p5svn6y2ymmju6nubxndf4pscryd.onion")); 314 const CService tor_service{tor_netaddr, Params().GetDefaultPort()}; 315 316 const std::array<CAddress, 3> addr{CAddress{ip(0xa0b0c001), NODE_NONE}, 317 CAddress{ip(0xa0b0c002), NODE_NONE}, 318 CAddress{tor_service, NODE_NONE}}; 319 320 const CNetAddr other_addr{ip(0xa0b0ff01)}; // Not any of addr[]. 321 322 std::array<CNode*, 3> nodes; 323 324 banman->ClearBanned(); 325 NodeId id{0}; 326 nodes[0] = new CNode{id++, 327 /*sock=*/nullptr, 328 addr[0], 329 /*nKeyedNetGroupIn=*/0, 330 /*nLocalHostNonceIn=*/0, 331 CAddress(), 332 /*addrNameIn=*/"", 333 ConnectionType::INBOUND, 334 /*inbound_onion=*/false, 335 /*network_key=*/1}; 336 nodes[0]->SetCommonVersion(PROTOCOL_VERSION); 337 peerLogic->InitializeNode(*nodes[0], NODE_NETWORK); 338 nodes[0]->fSuccessfullyConnected = true; 339 connman->AddTestNode(*nodes[0]); 340 peerLogic->UnitTestMisbehaving(nodes[0]->GetId()); // Should be discouraged 341 BOOST_CHECK(peerLogic->SendMessages(*nodes[0])); 342 343 BOOST_CHECK(banman->IsDiscouraged(addr[0])); 344 BOOST_CHECK(nodes[0]->fDisconnect); 345 BOOST_CHECK(!banman->IsDiscouraged(other_addr)); // Different address, not discouraged 346 347 nodes[1] = new CNode{id++, 348 /*sock=*/nullptr, 349 addr[1], 350 /*nKeyedNetGroupIn=*/1, 351 /*nLocalHostNonceIn=*/1, 352 CAddress(), 353 /*addrNameIn=*/"", 354 ConnectionType::INBOUND, 355 /*inbound_onion=*/false, 356 /*network_key=*/1}; 357 nodes[1]->SetCommonVersion(PROTOCOL_VERSION); 358 peerLogic->InitializeNode(*nodes[1], NODE_NETWORK); 359 nodes[1]->fSuccessfullyConnected = true; 360 connman->AddTestNode(*nodes[1]); 361 BOOST_CHECK(peerLogic->SendMessages(*nodes[1])); 362 // [0] is still discouraged/disconnected. 363 BOOST_CHECK(banman->IsDiscouraged(addr[0])); 364 BOOST_CHECK(nodes[0]->fDisconnect); 365 // [1] is not discouraged/disconnected yet. 366 BOOST_CHECK(!banman->IsDiscouraged(addr[1])); 367 BOOST_CHECK(!nodes[1]->fDisconnect); 368 peerLogic->UnitTestMisbehaving(nodes[1]->GetId()); 369 BOOST_CHECK(peerLogic->SendMessages(*nodes[1])); 370 // Expect both [0] and [1] to be discouraged/disconnected now. 371 BOOST_CHECK(banman->IsDiscouraged(addr[0])); 372 BOOST_CHECK(nodes[0]->fDisconnect); 373 BOOST_CHECK(banman->IsDiscouraged(addr[1])); 374 BOOST_CHECK(nodes[1]->fDisconnect); 375 376 // Make sure non-IP peers are discouraged and disconnected properly. 377 378 nodes[2] = new CNode{id++, 379 /*sock=*/nullptr, 380 addr[2], 381 /*nKeyedNetGroupIn=*/1, 382 /*nLocalHostNonceIn=*/1, 383 CAddress(), 384 /*addrNameIn=*/"", 385 ConnectionType::OUTBOUND_FULL_RELAY, 386 /*inbound_onion=*/false, 387 /*network_key=*/2}; 388 nodes[2]->SetCommonVersion(PROTOCOL_VERSION); 389 peerLogic->InitializeNode(*nodes[2], NODE_NETWORK); 390 nodes[2]->fSuccessfullyConnected = true; 391 connman->AddTestNode(*nodes[2]); 392 peerLogic->UnitTestMisbehaving(nodes[2]->GetId()); 393 BOOST_CHECK(peerLogic->SendMessages(*nodes[2])); 394 BOOST_CHECK(banman->IsDiscouraged(addr[0])); 395 BOOST_CHECK(banman->IsDiscouraged(addr[1])); 396 BOOST_CHECK(banman->IsDiscouraged(addr[2])); 397 BOOST_CHECK(nodes[0]->fDisconnect); 398 BOOST_CHECK(nodes[1]->fDisconnect); 399 BOOST_CHECK(nodes[2]->fDisconnect); 400 401 for (CNode* node : nodes) { 402 peerLogic->FinalizeNode(*node); 403 } 404 connman->ClearTestNodes(); 405 } 406 407 BOOST_AUTO_TEST_CASE(DoS_bantime) 408 { 409 LOCK(NetEventsInterface::g_msgproc_mutex); 410 411 auto banman = std::make_unique<BanMan>(m_args.GetDataDirBase() / "banlist", nullptr, DEFAULT_MISBEHAVING_BANTIME); 412 auto connman = std::make_unique<CConnman>(0x1337, 0x1337, *m_node.addrman, *m_node.netgroupman, Params()); 413 auto peerLogic = PeerManager::make(*connman, *m_node.addrman, banman.get(), *m_node.chainman, *m_node.mempool, *m_node.warnings, {}); 414 415 banman->ClearBanned(); 416 const NodeClockContext clock_ctx{}; // keep mocktime constant 417 418 CAddress addr(ip(0xa0b0c001), NODE_NONE); 419 NodeId id{0}; 420 CNode dummyNode{id++, 421 /*sock=*/nullptr, 422 addr, 423 /*nKeyedNetGroupIn=*/4, 424 /*nLocalHostNonceIn=*/4, 425 CAddress(), 426 /*addrNameIn=*/"", 427 ConnectionType::INBOUND, 428 /*inbound_onion=*/false, 429 /*network_key=*/1}; 430 dummyNode.SetCommonVersion(PROTOCOL_VERSION); 431 peerLogic->InitializeNode(dummyNode, NODE_NETWORK); 432 dummyNode.fSuccessfullyConnected = true; 433 434 peerLogic->UnitTestMisbehaving(dummyNode.GetId()); 435 BOOST_CHECK(peerLogic->SendMessages(dummyNode)); 436 BOOST_CHECK(banman->IsDiscouraged(addr)); 437 438 peerLogic->FinalizeNode(dummyNode); 439 } 440 441 BOOST_AUTO_TEST_SUITE_END()