diff --git a/src/net_permissions.h b/src/net_permissions.h index c00689465e1..bc979e3792c 100644 --- a/src/net_permissions.h +++ b/src/net_permissions.h @@ -31,7 +31,8 @@ enum class NetPermissionFlags : uint32_t { NoBan = (1U << 4) | Download, // Can query the mempool Mempool = (1U << 5), - // Can request addrs without hitting a privacy-preserving cache + // Can request addrs without hitting a privacy-preserving cache, and send us + // unlimited amounts of addrs. Addr = (1U << 7), // True if the user did not specifically set fine grained permissions diff --git a/src/net_processing.cpp b/src/net_processing.cpp index 315d2ac5cd8..9c4544df215 100644 --- a/src/net_processing.cpp +++ b/src/net_processing.cpp @@ -155,6 +155,13 @@ static constexpr uint32_t MAX_GETCFHEADERS_SIZE = 2000; 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}; +/** The maximum rate of address records we're willing to process on average. Can be bypassed using + * the NetPermissionFlags::Addr permission. */ +static constexpr double MAX_ADDR_RATE_PER_SECOND{0.1}; +/** The soft limit of the address processing token bucket (the regular MAX_ADDR_RATE_PER_SECOND + * based increments won't go above this, but the MAX_ADDR_TO_SEND increment following GETADDR + * is exempt from this limit. */ +static constexpr size_t MAX_ADDR_PROCESSING_TOKEN_BUCKET{MAX_ADDR_TO_SEND}; // Internal stuff namespace { @@ -233,6 +240,15 @@ struct Peer { std::atomic_bool m_wants_addrv2{false}; /** Whether this peer has already sent us a getaddr message. */ bool m_getaddr_recvd{false}; + /** Number of addr messages that can be processed from this peer. Start at 1 to + * permit self-announcement. */ + double m_addr_token_bucket{1.0}; + /** When m_addr_token_bucket was last updated */ + std::chrono::microseconds m_addr_token_timestamp{GetTime()}; + /** Total number of addresses that were dropped due to rate limiting. */ + std::atomic m_addr_rate_limited{0}; + /** Total number of addresses that were processed (excludes rate limited ones). */ + std::atomic m_addr_processed{0}; /** Set of txids to reconsider once their parent transactions have been accepted **/ std::set m_orphan_work_set GUARDED_BY(g_cs_orphans); @@ -1239,6 +1255,8 @@ bool PeerManagerImpl::GetNodeStateStats(NodeId nodeid, CNodeStateStats& stats) c } stats.m_ping_wait = ping_wait; + stats.m_addr_processed = peer->m_addr_processed.load(); + stats.m_addr_rate_limited = peer->m_addr_rate_limited.load(); return true; } @@ -2583,6 +2601,9 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type, // Get recent addresses m_connman.PushMessage(&pfrom, CNetMsgMaker(greatest_common_version).Make(NetMsgType::GETADDR)); peer->m_getaddr_sent = true; + // When requesting a getaddr, accept an additional MAX_ADDR_TO_SEND addresses in response + // (bypassing the MAX_ADDR_PROCESSING_TOKEN_BUCKET limit). + peer->m_addr_token_bucket += MAX_ADDR_TO_SEND; } if (!pfrom.IsInboundConn()) { @@ -2777,11 +2798,34 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type, std::vector vAddrOk; int64_t nNow = GetAdjustedTime(); int64_t nSince = nNow - 10 * 60; + + // Update/increment addr rate limiting bucket. + const auto current_time = GetTime(); + if (peer->m_addr_token_bucket < MAX_ADDR_PROCESSING_TOKEN_BUCKET) { + // Don't increment bucket if it's already full + const auto time_diff = std::max(current_time - peer->m_addr_token_timestamp, 0us); + const double increment = CountSecondsDouble(time_diff) * MAX_ADDR_RATE_PER_SECOND; + peer->m_addr_token_bucket = std::min(peer->m_addr_token_bucket + increment, MAX_ADDR_PROCESSING_TOKEN_BUCKET); + } + peer->m_addr_token_timestamp = current_time; + + const bool rate_limited = !pfrom.HasPermission(NetPermissionFlags::Addr); + uint64_t num_proc = 0; + uint64_t num_rate_limit = 0; + Shuffle(vAddr.begin(), vAddr.end(), FastRandomContext()); for (CAddress& addr : vAddr) { if (interruptMsgProc) return; + // Apply rate limiting. + if (rate_limited) { + if (peer->m_addr_token_bucket < 1.0) { + ++num_rate_limit; + continue; + } + peer->m_addr_token_bucket -= 1.0; + } // 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. @@ -2795,6 +2839,7 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type, // Do not process banned/discouraged addresses beyond remembering we received them continue; } + ++num_proc; bool fReachable = IsReachable(addr); if (addr.nTime > nSince && !peer->m_getaddr_sent && vAddr.size() <= 10 && addr.IsRoutable()) { // Relay to a limited number of other nodes @@ -2804,6 +2849,15 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type, if (fReachable) vAddrOk.push_back(addr); } + peer->m_addr_processed += num_proc; + peer->m_addr_rate_limited += num_rate_limit; + LogPrint(BCLog::NET, "Received addr: %u addresses (%u processed, %u rate-limited) from peer=%d%s\n", + vAddr.size(), + num_proc, + num_rate_limit, + pfrom.GetId(), + fLogIPs ? ", peeraddr=" + pfrom.addr.ToString() : ""); + m_addrman.Add(vAddrOk, pfrom.addr, 2 * 60 * 60); if (vAddr.size() < 1000) peer->m_getaddr_sent = false; if (pfrom.IsAddrFetchConn()) { diff --git a/src/net_processing.h b/src/net_processing.h index d5801aadd34..c537efb5db9 100644 --- a/src/net_processing.h +++ b/src/net_processing.h @@ -29,6 +29,8 @@ struct CNodeStateStats { int m_starting_height = -1; std::chrono::microseconds m_ping_wait; std::vector vHeightInFlight; + uint64_t m_addr_processed = 0; + uint64_t m_addr_rate_limited = 0; }; class PeerManager : public CValidationInterface, public NetEventsInterface diff --git a/src/rpc/net.cpp b/src/rpc/net.cpp index 3013c76825e..083ba31b712 100644 --- a/src/rpc/net.cpp +++ b/src/rpc/net.cpp @@ -242,6 +242,8 @@ static RPCHelpMan getpeerinfo() heights.push_back(height); } obj.pushKV("inflight", heights); + obj.pushKV("addr_processed", statestats.m_addr_processed); + obj.pushKV("addr_rate_limited", statestats.m_addr_rate_limited); } UniValue permissions(UniValue::VARR); for (const auto& permission : NetPermissions::ToStrings(stats.m_permissionFlags)) { diff --git a/test/functional/p2p_addr_relay.py b/test/functional/p2p_addr_relay.py index 1a414959b90..ff1d85a9be7 100755 --- a/test/functional/p2p_addr_relay.py +++ b/test/functional/p2p_addr_relay.py @@ -13,17 +13,20 @@ from test_framework.messages import ( msg_addr, msg_getaddr ) -from test_framework.p2p import P2PInterface -from test_framework.test_framework import BitcoinTestFramework -from test_framework.util import ( - assert_equal, +from test_framework.p2p import ( + P2PInterface, + p2p_lock, ) +from test_framework.test_framework import BitcoinTestFramework +from test_framework.util import assert_equal +import random import time class AddrReceiver(P2PInterface): num_ipv4_received = 0 test_addr_contents = False + _tokens = 1 def __init__(self, test_addr_contents=False): super().__init__() @@ -40,6 +43,20 @@ class AddrReceiver(P2PInterface): raise AssertionError("Invalid addr.port of {} (8333-8342 expected)".format(addr.port)) assert addr.ip.startswith('123.123.123.') + def on_getaddr(self, message): + # When the node sends us a getaddr, it increments the addr relay tokens for the connection by 1000 + self._tokens += 1000 + + @property + def tokens(self): + with p2p_lock: + return self._tokens + + def increment_tokens(self, n): + # When we move mocktime forward, the node increments the addr relay tokens for its peers + with p2p_lock: + self._tokens += n + def addr_received(self): return self.num_ipv4_received != 0 @@ -53,12 +70,14 @@ class AddrTest(BitcoinTestFramework): def set_test_params(self): self.num_nodes = 1 + self.extra_args = [["-whitelist=addr@127.0.0.1"]] def run_test(self): self.oversized_addr_test() self.relay_tests() self.getaddr_tests() self.blocksonly_mode_tests() + self.rate_limit_tests() def setup_addr_msg(self, num): addrs = [] @@ -75,6 +94,19 @@ class AddrTest(BitcoinTestFramework): msg.addrs = addrs return msg + def setup_rand_addr_msg(self, num): + addrs = [] + for i in range(num): + addr = CAddress() + addr.time = self.mocktime + i + addr.nServices = NODE_NETWORK | NODE_WITNESS + addr.ip = f"{random.randrange(128,169)}.{random.randrange(1,255)}.{random.randrange(1,255)}.{random.randrange(1,255)}" + addr.port = 8333 + addrs.append(addr) + msg = msg_addr() + msg.addrs = addrs + return msg + def send_addr_msg(self, source, msg, receivers): source.send_and_ping(msg) # pop m_next_addr_send timer @@ -191,7 +223,7 @@ class AddrTest(BitcoinTestFramework): def blocksonly_mode_tests(self): self.log.info('Test addr relay in -blocksonly mode') - self.restart_node(0, ["-blocksonly"]) + self.restart_node(0, ["-blocksonly", "-whitelist=addr@127.0.0.1"]) self.mocktime = int(time.time()) self.log.info('Check that we send getaddr messages') @@ -207,6 +239,63 @@ class AddrTest(BitcoinTestFramework): self.nodes[0].disconnect_p2ps() + def send_addrs_and_test_rate_limiting(self, peer, no_relay, new_addrs, total_addrs): + """Send an addr message and check that the number of addresses processed and rate-limited is as expected""" + + peer.send_and_ping(self.setup_rand_addr_msg(new_addrs)) + + peerinfo = self.nodes[0].getpeerinfo()[0] + addrs_processed = peerinfo['addr_processed'] + addrs_rate_limited = peerinfo['addr_rate_limited'] + self.log.debug(f"addrs_processed = {addrs_processed}, addrs_rate_limited = {addrs_rate_limited}") + + if no_relay: + assert_equal(addrs_processed, 0) + assert_equal(addrs_rate_limited, 0) + else: + assert_equal(addrs_processed, min(total_addrs, peer.tokens)) + assert_equal(addrs_rate_limited, max(0, total_addrs - peer.tokens)) + + def rate_limit_tests(self): + + self.mocktime = int(time.time()) + self.restart_node(0, []) + self.nodes[0].setmocktime(self.mocktime) + + for contype, no_relay in [("outbound-full-relay", False), ("block-relay-only", True), ("inbound", False)]: + self.log.info(f'Test rate limiting of addr processing for {contype} peers') + if contype == "inbound": + peer = self.nodes[0].add_p2p_connection(AddrReceiver()) + else: + peer = self.nodes[0].add_outbound_p2p_connection(AddrReceiver(), p2p_idx=0, connection_type=contype) + + # Send 600 addresses. For all but the block-relay-only peer this should result in addresses being processed. + self.send_addrs_and_test_rate_limiting(peer, no_relay, 600, 600) + + # Send 600 more addresses. For the outbound-full-relay peer (which we send a GETADDR, and thus will + # process up to 1001 incoming addresses), this means more addresses will be processed. + self.send_addrs_and_test_rate_limiting(peer, no_relay, 600, 1200) + + # Send 10 more. As we reached the processing limit for all nodes, no more addresses should be procesesd. + self.send_addrs_and_test_rate_limiting(peer, no_relay, 10, 1210) + + # Advance the time by 100 seconds, permitting the processing of 10 more addresses. + # Send 200 and verify that 10 are processed. + self.mocktime += 100 + self.nodes[0].setmocktime(self.mocktime) + peer.increment_tokens(10) + + self.send_addrs_and_test_rate_limiting(peer, no_relay, 200, 1410) + + # Advance the time by 1000 seconds, permitting the processing of 100 more addresses. + # Send 200 and verify that 100 are processed. + self.mocktime += 1000 + self.nodes[0].setmocktime(self.mocktime) + peer.increment_tokens(100) + + self.send_addrs_and_test_rate_limiting(peer, no_relay, 200, 1610) + + self.nodes[0].disconnect_p2ps() if __name__ == '__main__': AddrTest().main() diff --git a/test/functional/p2p_addrv2_relay.py b/test/functional/p2p_addrv2_relay.py index c006a6c24f8..32c1d42b1cf 100755 --- a/test/functional/p2p_addrv2_relay.py +++ b/test/functional/p2p_addrv2_relay.py @@ -42,7 +42,9 @@ class AddrReceiver(P2PInterface): super().__init__(support_addrv2 = True) def on_addrv2(self, message): - if ADDRS == message.addrs: + expected_set = set((addr.ip, addr.port) for addr in ADDRS) + received_set = set((addr.ip, addr.port) for addr in message.addrs) + if expected_set == received_set: self.addrv2_received_and_checked = True def wait_for_addrv2(self): @@ -53,6 +55,7 @@ class AddrTest(BitcoinTestFramework): def set_test_params(self): self.setup_clean_chain = True self.num_nodes = 1 + self.extra_args = [["-whitelist=addr@127.0.0.1"]] def run_test(self): self.log.info('Create connection that sends addrv2 messages') diff --git a/test/functional/p2p_invalid_messages.py b/test/functional/p2p_invalid_messages.py index 788a81d4af0..9c345063205 100755 --- a/test/functional/p2p_invalid_messages.py +++ b/test/functional/p2p_invalid_messages.py @@ -58,6 +58,7 @@ class InvalidMessagesTest(BitcoinTestFramework): def set_test_params(self): self.num_nodes = 1 self.setup_clean_chain = True + self.extra_args = [["-whitelist=addr@127.0.0.1"]] def run_test(self): self.test_buffer()