net: advertise support for ADDRv2 via new message

Introduce a new message `sendaddrv2` to signal support for ADDRv2.
Send the new message immediately after sending the `VERACK` message.

Add support for receiving and parsing ADDRv2 messages.

Send ADDRv2 messages (instead of ADDR) to a peer if he has
advertised support for it.

Co-authored-by: Carl Dong <contact@carldong.me>

src/net.h

@@ -868,6 +868,11 @@ public:
     bool m_legacyWhitelisted{false};
     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};
     std::atomic_bool fSuccessfullyConnected{false};
     // Setting fDisconnect to true will cause the node to be disconnected the
     // next time DisconnectNodes() runs
@@ -1115,11 +1120,16 @@ public:
 
     void PushAddress(const CAddress& _addr, FastRandomContext &insecure_rand)
     {
+        // Whether the peer supports the address in `_addr`. For example,
+        // nodes that do not implement BIP155 cannot receive Tor v3 addresses
+        // because they require ADDRv2 (BIP155) encoding.
+        const bool addr_format_supported = m_wants_addrv2 || _addr.IsAddrV1Compatible();
+
         // 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())) {
+        if (_addr.IsValid() && !m_addr_known->contains(_addr.GetKey()) && addr_format_supported) {
             if (vAddrToSend.size() >= MAX_ADDR_TO_SEND) {
                 vAddrToSend[insecure_rand.randrange(vAddrToSend.size())] = _addr;
             } else {

src/net_processing.cpp

@@ -23,6 +23,7 @@
 #include <random.h>
 #include <reverse_iterator.h>
 #include <scheduler.h>
+#include <streams.h>
 #include <tinyformat.h>
 #include <txmempool.h>
 #include <util/check.h> // For NDEBUG compile time check
@@ -2408,11 +2409,16 @@ void PeerManager::ProcessMessage(CNode& pfrom, const std::string& msg_type, CDat
         pfrom.SetCommonVersion(greatest_common_version);
         pfrom.nVersion = nVersion;
 
+        const CNetMsgMaker msg_maker(greatest_common_version);
+
         if (greatest_common_version >= WTXID_RELAY_VERSION) {
-            m_connman.PushMessage(&pfrom, CNetMsgMaker(greatest_common_version).Make(NetMsgType::WTXIDRELAY));
+            m_connman.PushMessage(&pfrom, msg_maker.Make(NetMsgType::WTXIDRELAY));
         }
 
-        m_connman.PushMessage(&pfrom, CNetMsgMaker(greatest_common_version).Make(NetMsgType::VERACK));
+        m_connman.PushMessage(&pfrom, msg_maker.Make(NetMsgType::VERACK));
+
+        // Signal ADDRv2 support (BIP155).
+        m_connman.PushMessage(&pfrom, msg_maker.Make(NetMsgType::SENDADDRV2));
 
         pfrom.nServices = nServices;
         pfrom.SetAddrLocal(addrMe);
@@ -2582,16 +2588,25 @@ void PeerManager::ProcessMessage(CNode& pfrom, const std::string& msg_type, CDat
         return;
     }
 
-    if (msg_type == NetMsgType::ADDR) {
+    if (msg_type == NetMsgType::ADDR || msg_type == NetMsgType::ADDRV2) {
+        int stream_version = vRecv.GetVersion();
+        if (msg_type == NetMsgType::ADDRV2) {
+            // Add ADDRV2_FORMAT to the version so that the CNetAddr and CAddress
+            // unserialize methods know that an address in v2 format is coming.
+            stream_version |= ADDRV2_FORMAT;
+        }
+
+        OverrideStream<CDataStream> s(&vRecv, vRecv.GetType(), stream_version);
         std::vector<CAddress> vAddr;
-        vRecv >> vAddr;
+
+        s >> vAddr;
 
         if (!pfrom.RelayAddrsWithConn()) {
             return;
         }
         if (vAddr.size() > MAX_ADDR_TO_SEND)
         {
-            Misbehaving(pfrom.GetId(), 20, strprintf("addr message size = %u", vAddr.size()));
+            Misbehaving(pfrom.GetId(), 20, strprintf("%s message size = %u", msg_type, vAddr.size()));
             return;
         }
 
@@ -2635,6 +2650,11 @@ void PeerManager::ProcessMessage(CNode& pfrom, const std::string& msg_type, CDat
         return;
     }
 
+    if (msg_type == NetMsgType::SENDADDRV2) {
+        pfrom.m_wants_addrv2 = true;
+        return;
+    }
+
     if (msg_type == NetMsgType::SENDHEADERS) {
         LOCK(cs_main);
         State(pfrom.GetId())->fPreferHeaders = true;
@@ -4095,6 +4115,17 @@ bool PeerManager::SendMessages(CNode* pto)
             std::vector<CAddress> vAddr;
             vAddr.reserve(pto->vAddrToSend.size());
             assert(pto->m_addr_known);
+
+            const char* msg_type;
+            int make_flags;
+            if (pto->m_wants_addrv2) {
+                msg_type = NetMsgType::ADDRV2;
+                make_flags = ADDRV2_FORMAT;
+            } else {
+                msg_type = NetMsgType::ADDR;
+                make_flags = 0;
+            }
+
             for (const CAddress& addr : pto->vAddrToSend)
             {
                 if (!pto->m_addr_known->contains(addr.GetKey()))
@@ -4104,14 +4135,14 @@ bool PeerManager::SendMessages(CNode* pto)
                     // receiver rejects addr messages larger than MAX_ADDR_TO_SEND
                     if (vAddr.size() >= MAX_ADDR_TO_SEND)
                     {
-                        m_connman.PushMessage(pto, msgMaker.Make(NetMsgType::ADDR, vAddr));
+                        m_connman.PushMessage(pto, msgMaker.Make(make_flags, msg_type, vAddr));
                         vAddr.clear();
                     }
                 }
             }
             pto->vAddrToSend.clear();
             if (!vAddr.empty())
-                m_connman.PushMessage(pto, msgMaker.Make(NetMsgType::ADDR, vAddr));
+                m_connman.PushMessage(pto, msgMaker.Make(make_flags, msg_type, vAddr));
             // we only send the big addr message once
             if (pto->vAddrToSend.capacity() > 40)
                 pto->vAddrToSend.shrink_to_fit();

src/netaddress.cpp

@@ -474,6 +474,26 @@ bool CNetAddr::IsInternal() const
    return m_net == NET_INTERNAL;
 }
 
+bool CNetAddr::IsAddrV1Compatible() const
+{
+    switch (m_net) {
+    case NET_IPV4:
+    case NET_IPV6:
+    case NET_INTERNAL:
+        return true;
+    case NET_ONION:
+        return m_addr.size() == ADDR_TORV2_SIZE;
+    case NET_I2P:
+    case NET_CJDNS:
+        return false;
+    case NET_UNROUTABLE: // m_net is never and should not be set to NET_UNROUTABLE
+    case NET_MAX:        // m_net is never and should not be set to NET_MAX
+        assert(false);
+    } // no default case, so the compiler can warn about missing cases
+
+    assert(false);
+}
+
 enum Network CNetAddr::GetNetwork() const
 {
     if (IsInternal())
@@ -744,9 +764,12 @@ std::vector<unsigned char> CNetAddr::GetGroup(const std::vector<bool> &asmap) co
 
 std::vector<unsigned char> CNetAddr::GetAddrBytes() const
 {
-    uint8_t serialized[V1_SERIALIZATION_SIZE];
+    if (IsAddrV1Compatible()) {
-    SerializeV1Array(serialized);
+        uint8_t serialized[V1_SERIALIZATION_SIZE];
-    return {std::begin(serialized), std::end(serialized)};
+        SerializeV1Array(serialized);
+        return {std::begin(serialized), std::end(serialized)};
+    }
+    return std::vector<unsigned char>(m_addr.begin(), m_addr.end());
 }
 
 uint64_t CNetAddr::GetHash() const

src/netaddress.h

@@ -173,6 +173,12 @@ class CNetAddr
         bool IsRoutable() const;
         bool IsInternal() const;
         bool IsValid() const;
+
+        /**
+         * Check if the current object can be serialized in pre-ADDRv2/BIP155 format.
+         */
+        bool IsAddrV1Compatible() const;
+
         enum Network GetNetwork() const;
         std::string ToString() const;
         std::string ToStringIP() const;

src/protocol.cpp

@@ -14,6 +14,8 @@ namespace NetMsgType {
 const char *VERSION="version";
 const char *VERACK="verack";
 const char *ADDR="addr";
+const char *ADDRV2="addrv2";
+const char *SENDADDRV2="sendaddrv2";
 const char *INV="inv";
 const char *GETDATA="getdata";
 const char *MERKLEBLOCK="merkleblock";
@@ -52,6 +54,8 @@ const static std::string allNetMessageTypes[] = {
     NetMsgType::VERSION,
     NetMsgType::VERACK,
     NetMsgType::ADDR,
+    NetMsgType::ADDRV2,
+    NetMsgType::SENDADDRV2,
     NetMsgType::INV,
     NetMsgType::GETDATA,
     NetMsgType::MERKLEBLOCK,

src/protocol.h

@@ -76,6 +76,18 @@ extern const char* VERACK;
  * network.
  */
 extern const char* ADDR;
+/**
+ * The addrv2 message relays connection information for peers on the network just
+ * like the addr message, but is extended to allow gossiping of longer node
+ * addresses (see BIP155).
+ */
+extern const char *ADDRV2;
+/**
+ * The sendaddrv2 message signals support for receiving ADDRV2 messages (BIP155).
+ * It also implies that its sender can encode as ADDRV2 and would send ADDRV2
+ * instead of ADDR to a peer that has signaled ADDRV2 support by sending SENDADDRV2.
+ */
+extern const char *SENDADDRV2;
 /**
  * The inv message (inventory message) transmits one or more inventories of
  * objects known to the transmitting peer.

src/test/net_tests.cpp

@@ -212,6 +212,7 @@ BOOST_AUTO_TEST_CASE(cnetaddr_basic)
     BOOST_REQUIRE(addr.IsIPv4());
 
     BOOST_CHECK(addr.IsBindAny());
+    BOOST_CHECK(addr.IsAddrV1Compatible());
     BOOST_CHECK_EQUAL(addr.ToString(), "0.0.0.0");
 
     // IPv4, INADDR_NONE
@@ -220,6 +221,7 @@ BOOST_AUTO_TEST_CASE(cnetaddr_basic)
     BOOST_REQUIRE(addr.IsIPv4());
 
     BOOST_CHECK(!addr.IsBindAny());
+    BOOST_CHECK(addr.IsAddrV1Compatible());
     BOOST_CHECK_EQUAL(addr.ToString(), "255.255.255.255");
 
     // IPv4, casual
@@ -228,6 +230,7 @@ BOOST_AUTO_TEST_CASE(cnetaddr_basic)
     BOOST_REQUIRE(addr.IsIPv4());
 
     BOOST_CHECK(!addr.IsBindAny());
+    BOOST_CHECK(addr.IsAddrV1Compatible());
     BOOST_CHECK_EQUAL(addr.ToString(), "12.34.56.78");
 
     // IPv6, in6addr_any
@@ -236,6 +239,7 @@ BOOST_AUTO_TEST_CASE(cnetaddr_basic)
     BOOST_REQUIRE(addr.IsIPv6());
 
     BOOST_CHECK(addr.IsBindAny());
+    BOOST_CHECK(addr.IsAddrV1Compatible());
     BOOST_CHECK_EQUAL(addr.ToString(), "::");
 
     // IPv6, casual
@@ -244,6 +248,7 @@ BOOST_AUTO_TEST_CASE(cnetaddr_basic)
     BOOST_REQUIRE(addr.IsIPv6());
 
     BOOST_CHECK(!addr.IsBindAny());
+    BOOST_CHECK(addr.IsAddrV1Compatible());
     BOOST_CHECK_EQUAL(addr.ToString(), "1122:3344:5566:7788:9900:aabb:ccdd:eeff");
 
     // TORv2
@@ -252,6 +257,7 @@ BOOST_AUTO_TEST_CASE(cnetaddr_basic)
     BOOST_REQUIRE(addr.IsTor());
 
     BOOST_CHECK(!addr.IsBindAny());
+    BOOST_CHECK(addr.IsAddrV1Compatible());
     BOOST_CHECK_EQUAL(addr.ToString(), "6hzph5hv6337r6p2.onion");
 
     // TORv3
@@ -261,6 +267,7 @@ BOOST_AUTO_TEST_CASE(cnetaddr_basic)
     BOOST_REQUIRE(addr.IsTor());
 
     BOOST_CHECK(!addr.IsBindAny());
+    BOOST_CHECK(!addr.IsAddrV1Compatible());
     BOOST_CHECK_EQUAL(addr.ToString(), torv3_addr);
 
     // TORv3, broken, with wrong checksum
@@ -285,6 +292,7 @@ BOOST_AUTO_TEST_CASE(cnetaddr_basic)
     BOOST_REQUIRE(addr.IsInternal());
 
     BOOST_CHECK(!addr.IsBindAny());
+    BOOST_CHECK(addr.IsAddrV1Compatible());
     BOOST_CHECK_EQUAL(addr.ToString(), "esffpvrt3wpeaygy.internal");
 
     // Totally bogus
@@ -379,6 +387,7 @@ BOOST_AUTO_TEST_CASE(cnetaddr_unserialize_v2)
     s >> addr;
     BOOST_CHECK(addr.IsValid());
     BOOST_CHECK(addr.IsIPv4());
+    BOOST_CHECK(addr.IsAddrV1Compatible());
     BOOST_CHECK_EQUAL(addr.ToString(), "1.2.3.4");
     BOOST_REQUIRE(s.empty());
 
@@ -415,6 +424,7 @@ BOOST_AUTO_TEST_CASE(cnetaddr_unserialize_v2)
     s >> addr;
     BOOST_CHECK(addr.IsValid());
     BOOST_CHECK(addr.IsIPv6());
+    BOOST_CHECK(addr.IsAddrV1Compatible());
     BOOST_CHECK_EQUAL(addr.ToString(), "102:304:506:708:90a:b0c:d0e:f10");
     BOOST_REQUIRE(s.empty());
 
@@ -426,6 +436,7 @@ BOOST_AUTO_TEST_CASE(cnetaddr_unserialize_v2)
                                               // sha256(name)[0:10]
     s >> addr;
     BOOST_CHECK(addr.IsInternal());
+    BOOST_CHECK(addr.IsAddrV1Compatible());
     BOOST_CHECK_EQUAL(addr.ToString(), "zklycewkdo64v6wc.internal");
     BOOST_REQUIRE(s.empty());
 
@@ -461,6 +472,7 @@ BOOST_AUTO_TEST_CASE(cnetaddr_unserialize_v2)
     s >> addr;
     BOOST_CHECK(addr.IsValid());
     BOOST_CHECK(addr.IsTor());
+    BOOST_CHECK(addr.IsAddrV1Compatible());
     BOOST_CHECK_EQUAL(addr.ToString(), "6hzph5hv6337r6p2.onion");
     BOOST_REQUIRE(s.empty());
 
@@ -482,6 +494,7 @@ BOOST_AUTO_TEST_CASE(cnetaddr_unserialize_v2)
     s >> addr;
     BOOST_CHECK(addr.IsValid());
     BOOST_CHECK(addr.IsTor());
+    BOOST_CHECK(!addr.IsAddrV1Compatible());
     BOOST_CHECK_EQUAL(addr.ToString(),
                       "pg6mmjiyjmcrsslvykfwnntlaru7p5svn6y2ymmju6nubxndf4pscryd.onion");
     BOOST_REQUIRE(s.empty());
@@ -503,6 +516,8 @@ BOOST_AUTO_TEST_CASE(cnetaddr_unserialize_v2)
                            "f98232ae42d4b6fd2fa81952dfe36a87"));
     s >> addr;
     BOOST_CHECK(addr.IsValid());
+    BOOST_CHECK(addr.IsI2P());
+    BOOST_CHECK(!addr.IsAddrV1Compatible());
     BOOST_CHECK_EQUAL(addr.ToString(),
                       "ukeu3k5oycgaauneqgtnvselmt4yemvoilkln7jpvamvfx7dnkdq.b32.i2p");
     BOOST_REQUIRE(s.empty());
@@ -524,6 +539,8 @@ BOOST_AUTO_TEST_CASE(cnetaddr_unserialize_v2)
                            ));
     s >> addr;
     BOOST_CHECK(addr.IsValid());
+    BOOST_CHECK(addr.IsCJDNS());
+    BOOST_CHECK(!addr.IsAddrV1Compatible());
     BOOST_CHECK_EQUAL(addr.ToString(), "fc00:1:2:3:4:5:6:7");
     BOOST_REQUIRE(s.empty());
 

test/functional/p2p_addrv2_relay.py

@@ -0,0 +1,79 @@
+#!/usr/bin/env python3
+# Copyright (c) 2020 The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+"""
+Test addrv2 relay
+"""
+
+import time
+
+from test_framework.messages import (
+    CAddress,
+    msg_addrv2,
+    NODE_NETWORK,
+    NODE_WITNESS,
+)
+from test_framework.p2p import P2PInterface
+from test_framework.test_framework import BitcoinTestFramework
+from test_framework.util import assert_equal
+
+ADDRS = []
+for i in range(10):
+    addr = CAddress()
+    addr.time = int(time.time()) + i
+    addr.nServices = NODE_NETWORK | NODE_WITNESS
+    addr.ip = "123.123.123.{}".format(i % 256)
+    addr.port = 8333 + i
+    ADDRS.append(addr)
+
+
+class AddrReceiver(P2PInterface):
+    addrv2_received_and_checked = False
+
+    def __init__(self):
+        super().__init__(support_addrv2 = True)
+
+    def on_addrv2(self, message):
+        for addr in message.addrs:
+            assert_equal(addr.nServices, 9)
+            assert addr.ip.startswith('123.123.123.')
+            assert (8333 <= addr.port < 8343)
+        self.addrv2_received_and_checked = True
+
+    def wait_for_addrv2(self):
+        self.wait_until(lambda: "addrv2" in self.last_message)
+
+
+class AddrTest(BitcoinTestFramework):
+    def set_test_params(self):
+        self.setup_clean_chain = True
+        self.num_nodes = 1
+
+    def run_test(self):
+        self.log.info('Create connection that sends addrv2 messages')
+        addr_source = self.nodes[0].add_p2p_connection(P2PInterface())
+        msg = msg_addrv2()
+
+        self.log.info('Send too-large addrv2 message')
+        msg.addrs = ADDRS * 101
+        with self.nodes[0].assert_debug_log(['addrv2 message size = 1010']):
+            addr_source.send_and_ping(msg)
+
+        self.log.info('Check that addrv2 message content is relayed and added to addrman')
+        addr_receiver = self.nodes[0].add_p2p_connection(AddrReceiver())
+        msg.addrs = ADDRS
+        with self.nodes[0].assert_debug_log([
+                'Added 10 addresses from 127.0.0.1: 0 tried',
+                'received: addrv2 (131 bytes) peer=0',
+                'sending addrv2 (131 bytes) peer=1',
+        ]):
+            addr_source.send_and_ping(msg)
+            self.nodes[0].setmocktime(int(time.time()) + 30 * 60)
+            addr_receiver.wait_for_addrv2()
+
+        assert addr_receiver.addrv2_received_and_checked
+
+
+if __name__ == '__main__':
+    AddrTest().main()

test/functional/p2p_invalid_messages.py

@@ -4,6 +4,9 @@
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 """Test node responses to invalid network messages."""
 
+import struct
+import time
+
 from test_framework.messages import (
     CBlockHeader,
     CInv,
@@ -22,7 +25,10 @@ from test_framework.p2p import (
     P2PInterface,
 )
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import assert_equal
+from test_framework.util import (
+    assert_equal,
+    hex_str_to_bytes,
+)
 
 VALID_DATA_LIMIT = MAX_PROTOCOL_MESSAGE_LENGTH - 5  # Account for the 5-byte length prefix
 
@@ -42,6 +48,11 @@ class msg_unrecognized:
         return "{}(data={})".format(self.msgtype, self.str_data)
 
 
+class SenderOfAddrV2(P2PInterface):
+    def wait_for_sendaddrv2(self):
+        self.wait_until(lambda: 'sendaddrv2' in self.last_message)
+
+
 class InvalidMessagesTest(BitcoinTestFramework):
     def set_test_params(self):
         self.num_nodes = 1
@@ -53,6 +64,10 @@ class InvalidMessagesTest(BitcoinTestFramework):
         self.test_checksum()
         self.test_size()
         self.test_msgtype()
+        self.test_addrv2_empty()
+        self.test_addrv2_no_addresses()
+        self.test_addrv2_too_long_address()
+        self.test_addrv2_unrecognized_network()
         self.test_oversized_inv_msg()
         self.test_oversized_getdata_msg()
         self.test_oversized_headers_msg()
@@ -127,6 +142,84 @@ class InvalidMessagesTest(BitcoinTestFramework):
         assert_equal(self.nodes[0].getpeerinfo()[0]['bytesrecv_per_msg']['*other*'], 26)
         self.nodes[0].disconnect_p2ps()
 
+    def test_addrv2(self, label, required_log_messages, raw_addrv2):
+        node = self.nodes[0]
+        conn = node.add_p2p_connection(SenderOfAddrV2())
+
+        # Make sure bitcoind signals support for ADDRv2, otherwise this test
+        # will bombard an old node with messages it does not recognize which
+        # will produce unexpected results.
+        conn.wait_for_sendaddrv2()
+
+        self.log.info('Test addrv2: ' + label)
+
+        msg = msg_unrecognized(str_data=b'')
+        msg.msgtype = b'addrv2'
+        with node.assert_debug_log(required_log_messages):
+            # override serialize() which would include the length of the data
+            msg.serialize = lambda: raw_addrv2
+            conn.send_raw_message(conn.build_message(msg))
+            conn.sync_with_ping()
+
+        node.disconnect_p2ps()
+
+    def test_addrv2_empty(self):
+        self.test_addrv2('empty',
+            [
+                'received: addrv2 (0 bytes)',
+                'ProcessMessages(addrv2, 0 bytes): Exception',
+                'end of data',
+            ],
+            b'')
+
+    def test_addrv2_no_addresses(self):
+        self.test_addrv2('no addresses',
+            [
+                'received: addrv2 (1 bytes)',
+            ],
+            hex_str_to_bytes('00'))
+
+    def test_addrv2_too_long_address(self):
+        self.test_addrv2('too long address',
+            [
+                'received: addrv2 (525 bytes)',
+                'ProcessMessages(addrv2, 525 bytes): Exception',
+                'Address too long: 513 > 512',
+            ],
+            hex_str_to_bytes(
+                '01' +       # number of entries
+                '61bc6649' + # time, Fri Jan  9 02:54:25 UTC 2009
+                '00' +       # service flags, COMPACTSIZE(NODE_NONE)
+                '01' +       # network type (IPv4)
+                'fd0102' +   # address length (COMPACTSIZE(513))
+                'ab' * 513 + # address
+                '208d'))     # port
+
+    def test_addrv2_unrecognized_network(self):
+        now_hex = struct.pack('<I', int(time.time())).hex()
+        self.test_addrv2('unrecognized network',
+            [
+                'received: addrv2 (25 bytes)',
+                'IP 9.9.9.9 mapped',
+                'Added 1 addresses',
+            ],
+            hex_str_to_bytes(
+                '02' +     # number of entries
+                # this should be ignored without impeding acceptance of subsequent ones
+                now_hex +  # time
+                '01' +     # service flags, COMPACTSIZE(NODE_NETWORK)
+                '99' +     # network type (unrecognized)
+                '02' +     # address length (COMPACTSIZE(2))
+                'ab' * 2 + # address
+                '208d' +   # port
+                # this should be added:
+                now_hex +  # time
+                '01' +     # service flags, COMPACTSIZE(NODE_NETWORK)
+                '01' +     # network type (IPv4)
+                '04' +     # address length (COMPACTSIZE(4))
+                '09' * 4 + # address
+                '208d'))   # port
+
     def test_oversized_msg(self, msg, size):
         msg_type = msg.msgtype.decode('ascii')
         self.log.info("Test {} message of size {} is logged as misbehaving".format(msg_type, size))

test/functional/test_framework/messages.py

@@ -136,12 +136,17 @@ def uint256_from_compact(c):
     return v
 
 
-def deser_vector(f, c):
+# deser_function_name: Allow for an alternate deserialization function on the
+# entries in the vector.
+def deser_vector(f, c, deser_function_name=None):
     nit = deser_compact_size(f)
     r = []
     for _ in range(nit):
         t = c()
-        t.deserialize(f)
+        if deser_function_name:
+            getattr(t, deser_function_name)(f)
+        else:
+            t.deserialize(f)
         r.append(t)
     return r
 
@@ -204,38 +209,82 @@ def ToHex(obj):
 
 
 class CAddress:
-    __slots__ = ("ip", "nServices", "pchReserved", "port", "time")
+    __slots__ = ("net", "ip", "nServices", "port", "time")
+
+    # see https://github.com/bitcoin/bips/blob/master/bip-0155.mediawiki
+    NET_IPV4 = 1
+
+    ADDRV2_NET_NAME = {
+        NET_IPV4: "IPv4"
+    }
+
+    ADDRV2_ADDRESS_LENGTH = {
+        NET_IPV4: 4
+    }
 
     def __init__(self):
         self.time = 0
         self.nServices = 1
-        self.pchReserved = b"\x00" * 10 + b"\xff" * 2
+        self.net = self.NET_IPV4
         self.ip = "0.0.0.0"
         self.port = 0
 
     def deserialize(self, f, *, with_time=True):
+        """Deserialize from addrv1 format (pre-BIP155)"""
         if with_time:
             # VERSION messages serialize CAddress objects without time
-            self.time = struct.unpack("<i", f.read(4))[0]
+            self.time = struct.unpack("<I", f.read(4))[0]
         self.nServices = struct.unpack("<Q", f.read(8))[0]
-        self.pchReserved = f.read(12)
+        # We only support IPv4 which means skip 12 bytes and read the next 4 as IPv4 address.
+        f.read(12)
+        self.net = self.NET_IPV4
         self.ip = socket.inet_ntoa(f.read(4))
         self.port = struct.unpack(">H", f.read(2))[0]
 
     def serialize(self, *, with_time=True):
+        """Serialize in addrv1 format (pre-BIP155)"""
+        assert self.net == self.NET_IPV4
         r = b""
         if with_time:
             # VERSION messages serialize CAddress objects without time
-            r += struct.pack("<i", self.time)
+            r += struct.pack("<I", self.time)
         r += struct.pack("<Q", self.nServices)
-        r += self.pchReserved
+        r += b"\x00" * 10 + b"\xff" * 2
+        r += socket.inet_aton(self.ip)
+        r += struct.pack(">H", self.port)
+        return r
+
+    def deserialize_v2(self, f):
+        """Deserialize from addrv2 format (BIP155)"""
+        self.time = struct.unpack("<I", f.read(4))[0]
+
+        self.nServices = deser_compact_size(f)
+
+        self.net = struct.unpack("B", f.read(1))[0]
+        assert self.net == self.NET_IPV4
+
+        address_length = deser_compact_size(f)
+        assert address_length == self.ADDRV2_ADDRESS_LENGTH[self.net]
+
+        self.ip = socket.inet_ntoa(f.read(4))
+
+        self.port = struct.unpack(">H", f.read(2))[0]
+
+    def serialize_v2(self):
+        """Serialize in addrv2 format (BIP155)"""
+        assert self.net == self.NET_IPV4
+        r = b""
+        r += struct.pack("<I", self.time)
+        r += ser_compact_size(self.nServices)
+        r += struct.pack("B", self.net)
+        r += ser_compact_size(self.ADDRV2_ADDRESS_LENGTH[self.net])
         r += socket.inet_aton(self.ip)
         r += struct.pack(">H", self.port)
         return r
 
     def __repr__(self):
-        return "CAddress(nServices=%i ip=%s port=%i)" % (self.nServices,
+        return ("CAddress(nServices=%i net=%s addr=%s port=%i)"
-                                                         self.ip, self.port)
+                % (self.nServices, self.ADDRV2_NET_NAME[self.net], self.ip, self.port))
 
 
 class CInv:
@@ -1064,6 +1113,40 @@ class msg_addr:
         return "msg_addr(addrs=%s)" % (repr(self.addrs))
 
 
+class msg_addrv2:
+    __slots__ = ("addrs",)
+    msgtype = b"addrv2"
+
+    def __init__(self):
+        self.addrs = []
+
+    def deserialize(self, f):
+        self.addrs = deser_vector(f, CAddress, "deserialize_v2")
+
+    def serialize(self):
+        return ser_vector(self.addrs, "serialize_v2")
+
+    def __repr__(self):
+        return "msg_addrv2(addrs=%s)" % (repr(self.addrs))
+
+
+class msg_sendaddrv2:
+    __slots__ = ()
+    msgtype = b"sendaddrv2"
+
+    def __init__(self):
+        pass
+
+    def deserialize(self, f):
+        pass
+
+    def serialize(self):
+        return b""
+
+    def __repr__(self):
+        return "msg_sendaddrv2()"
+
+
 class msg_inv:
     __slots__ = ("inv",)
     msgtype = b"inv"

test/functional/test_framework/p2p.py

@@ -33,6 +33,7 @@ from test_framework.messages import (
     MAX_HEADERS_RESULTS,
     MIN_VERSION_SUPPORTED,
     msg_addr,
+    msg_addrv2,
     msg_block,
     MSG_BLOCK,
     msg_blocktxn,
@@ -56,6 +57,7 @@ from test_framework.messages import (
     msg_notfound,
     msg_ping,
     msg_pong,
+    msg_sendaddrv2,
     msg_sendcmpct,
     msg_sendheaders,
     msg_tx,
@@ -75,6 +77,7 @@ logger = logging.getLogger("TestFramework.p2p")
 
 MESSAGEMAP = {
     b"addr": msg_addr,
+    b"addrv2": msg_addrv2,
     b"block": msg_block,
     b"blocktxn": msg_blocktxn,
     b"cfcheckpt": msg_cfcheckpt,
@@ -97,6 +100,7 @@ MESSAGEMAP = {
     b"notfound": msg_notfound,
     b"ping": msg_ping,
     b"pong": msg_pong,
+    b"sendaddrv2": msg_sendaddrv2,
     b"sendcmpct": msg_sendcmpct,
     b"sendheaders": msg_sendheaders,
     b"tx": msg_tx,
@@ -285,7 +289,7 @@ class P2PInterface(P2PConnection):
 
     Individual testcases should subclass this and override the on_* methods
     if they want to alter message handling behaviour."""
-    def __init__(self):
+    def __init__(self, support_addrv2=False):
         super().__init__()
 
         # Track number of messages of each type received.
@@ -303,6 +307,8 @@ class P2PInterface(P2PConnection):
         # The network services received from the peer
         self.nServices = 0
 
+        self.support_addrv2 = support_addrv2
+
     def peer_connect(self, *args, services=NODE_NETWORK|NODE_WITNESS, send_version=True, **kwargs):
         create_conn = super().peer_connect(*args, **kwargs)
 
@@ -345,6 +351,7 @@ class P2PInterface(P2PConnection):
         pass
 
     def on_addr(self, message): pass
+    def on_addrv2(self, message): pass
     def on_block(self, message): pass
     def on_blocktxn(self, message): pass
     def on_cfcheckpt(self, message): pass
@@ -365,6 +372,7 @@ class P2PInterface(P2PConnection):
     def on_merkleblock(self, message): pass
     def on_notfound(self, message): pass
     def on_pong(self, message): pass
+    def on_sendaddrv2(self, message): pass
     def on_sendcmpct(self, message): pass
     def on_sendheaders(self, message): pass
     def on_tx(self, message): pass
@@ -389,6 +397,8 @@ class P2PInterface(P2PConnection):
         if message.nVersion >= 70016:
             self.send_message(msg_wtxidrelay())
         self.send_message(msg_verack())
+        if self.support_addrv2:
+            self.send_message(msg_sendaddrv2())
         self.nServices = message.nServices
 
     # Connection helper methods

test/functional/test_runner.py

@@ -154,6 +154,7 @@ BASE_SCRIPTS = [
     'feature_proxy.py',
     'rpc_signrawtransaction.py',
     'wallet_groups.py',
+    'p2p_addrv2_relay.py',
     'p2p_disconnect_ban.py',
     'rpc_decodescript.py',
     'rpc_blockchain.py',