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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server440 file guides

Release published 2026-10-28 · Snapshot fetched 2026-11-01. Latest stable release at fetch time; development branches and Git history are excluded. Only the selected code window and visible folders load here.

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1#!/usr/bin/env python3
2# Copyright (c) 2021-present The Bitcoin Core developers
3# Distributed under the MIT software license, see the accompanying
4# file COPYING or http://www.opensource.org/licenses/mit-license.php.
5"""
6Test v2 transport
7"""
8import socket
9
10from test_framework.messages import MAGIC_BYTES, NODE_P2P_V2
11from test_framework.test_framework import BitcoinTestFramework
12from test_framework.util import (
13    assert_not_equal,
14    assert_equal,
15    p2p_port,
16    assert_raises_rpc_error
17)
18
19
20class V2TransportTest(BitcoinTestFramework):
21    def set_test_params(self):
22        self.setup_clean_chain = True
23        self.num_nodes = 5
24        self.extra_args = [["-v2transport=1"], ["-v2transport=1"], ["-v2transport=0"], ["-v2transport=0"], ["-v2transport=0"]]
25
26    def run_test(self):
27        sending_handshake = "start sending v2 handshake to peer"
28        downgrading_to_v1 = "retrying with v1 transport protocol for peer"
29        self.disconnect_nodes(0, 1)
30        self.disconnect_nodes(1, 2)
31        self.disconnect_nodes(2, 3)
32        self.disconnect_nodes(3, 4)
33
34        # verify local services
35        network_info = self.nodes[2].getnetworkinfo()
36        assert_equal(int(network_info["localservices"], 16) & NODE_P2P_V2, 0)
37        assert "P2P_V2" not in network_info["localservicesnames"]
38        network_info = self.nodes[1].getnetworkinfo()
39        assert_equal(int(network_info["localservices"], 16) & NODE_P2P_V2, NODE_P2P_V2)
40        assert "P2P_V2" in network_info["localservicesnames"]
41
42        # V2 nodes can sync with V2 nodes
43        assert_equal(self.nodes[0].getblockcount(), 0)
44        assert_equal(self.nodes[1].getblockcount(), 0)
45        with self.nodes[0].assert_debug_log(expected_msgs=[sending_handshake],
46                                            unexpected_msgs=[downgrading_to_v1]):
47            self.connect_nodes(0, 1, peer_advertises_v2=True)
48        self.generate(self.nodes[0], 5, sync_fun=lambda: self.sync_all(self.nodes[0:2]))
49        assert_equal(self.nodes[1].getblockcount(), 5)
50        # verify there is a v2 connection between node 0 and 1
51        node_0_info = self.nodes[0].getpeerinfo()
52        node_1_info = self.nodes[1].getpeerinfo()
53        assert_equal(len(node_0_info), 1)
54        assert_equal(len(node_1_info), 1)
55        assert_equal(node_0_info[0]["transport_protocol_type"], "v2")
56        assert_equal(node_1_info[0]["transport_protocol_type"], "v2")
57        assert_equal(len(node_0_info[0]["session_id"]), 64)
58        assert_equal(len(node_1_info[0]["session_id"]), 64)
59        assert_equal(node_0_info[0]["session_id"], node_1_info[0]["session_id"])
60
61        # V1 nodes can sync with each other
62        assert_equal(self.nodes[2].getblockcount(), 0)
63        assert_equal(self.nodes[3].getblockcount(), 0)
64
65        # addnode rpc error when v2transport requested but not enabled
66        ip_port = "127.0.0.1:{}".format(p2p_port(3))
67        assert_raises_rpc_error(-8, "Error: v2transport requested but not enabled (see -v2transport)", self.nodes[2].addnode, node=ip_port, command='add', v2transport=True)
68
69        with self.nodes[2].assert_debug_log(expected_msgs=[],
70                                            unexpected_msgs=[sending_handshake, downgrading_to_v1]):
71            self.connect_nodes(2, 3, peer_advertises_v2=False)
72        self.generate(self.nodes[2], 8, sync_fun=lambda: self.sync_all(self.nodes[2:4]))
73        assert_equal(self.nodes[3].getblockcount(), 8)
74        assert_not_equal(self.nodes[0].getbestblockhash(), self.nodes[2].getbestblockhash())
75        # verify there is a v1 connection between node 2 and 3
76        node_2_info = self.nodes[2].getpeerinfo()
77        node_3_info = self.nodes[3].getpeerinfo()
78        assert_equal(len(node_2_info), 1)
79        assert_equal(len(node_3_info), 1)
80        assert_equal(node_2_info[0]["transport_protocol_type"], "v1")
81        assert_equal(node_3_info[0]["transport_protocol_type"], "v1")
82        assert_equal(len(node_2_info[0]["session_id"]), 0)
83        assert_equal(len(node_3_info[0]["session_id"]), 0)
84
85        # V1 nodes can sync with V2 nodes
86        self.disconnect_nodes(0, 1)
87        self.disconnect_nodes(2, 3)
88        with self.nodes[2].assert_debug_log(expected_msgs=[],
89                                            unexpected_msgs=[sending_handshake, downgrading_to_v1]):
90            self.connect_nodes(2, 1, peer_advertises_v2=False) # cannot enable v2 on v1 node
91        self.sync_all(self.nodes[1:3])
92        assert_equal(self.nodes[1].getblockcount(), 8)
93        assert_not_equal(self.nodes[0].getbestblockhash(), self.nodes[1].getbestblockhash())
94        # verify there is a v1 connection between node 1 and 2
95        node_1_info = self.nodes[1].getpeerinfo()
96        node_2_info = self.nodes[2].getpeerinfo()
97        assert_equal(len(node_1_info), 1)
98        assert_equal(len(node_2_info), 1)
99        assert_equal(node_1_info[0]["transport_protocol_type"], "v1")
100        assert_equal(node_2_info[0]["transport_protocol_type"], "v1")
101        assert_equal(len(node_1_info[0]["session_id"]), 0)
102        assert_equal(len(node_2_info[0]["session_id"]), 0)
103
104        # V2 nodes can sync with V1 nodes
105        self.disconnect_nodes(1, 2)
106        with self.nodes[0].assert_debug_log(expected_msgs=[],
107                                            unexpected_msgs=[sending_handshake, downgrading_to_v1]):
108            self.connect_nodes(0, 3, peer_advertises_v2=False)
109        self.sync_all([self.nodes[0], self.nodes[3]])
110        assert_equal(self.nodes[0].getblockcount(), 8)
111        # verify there is a v1 connection between node 0 and 3
112        node_0_info = self.nodes[0].getpeerinfo()
113        node_3_info = self.nodes[3].getpeerinfo()
114        assert_equal(len(node_0_info), 1)
115        assert_equal(len(node_3_info), 1)
116        assert_equal(node_0_info[0]["transport_protocol_type"], "v1")
117        assert_equal(node_3_info[0]["transport_protocol_type"], "v1")
118        assert_equal(len(node_0_info[0]["session_id"]), 0)
119        assert_equal(len(node_3_info[0]["session_id"]), 0)
120
121        # V2 node mines another block and everyone gets it
122        self.connect_nodes(0, 1, peer_advertises_v2=True)
123        self.connect_nodes(1, 2, peer_advertises_v2=False)
124        self.generate(self.nodes[1], 1, sync_fun=lambda: self.sync_all(self.nodes[0:4]))
125        assert_equal(self.nodes[0].getblockcount(), 9) # sync_all() verifies tip hashes match
126
127        # V1 node mines another block and everyone gets it
128        self.generate(self.nodes[3], 2, sync_fun=lambda: self.sync_all(self.nodes[0:4]))
129        assert_equal(self.nodes[2].getblockcount(), 11) # sync_all() verifies tip hashes match
130
131        assert_equal(self.nodes[4].getblockcount(), 0)
132        # Peer 4 is v1 p2p, but is falsely advertised as v2.
133        with self.nodes[1].assert_debug_log(expected_msgs=[sending_handshake, downgrading_to_v1]):
134            self.connect_nodes(1, 4, peer_advertises_v2=True)
135        self.sync_all()
136        assert_equal(self.nodes[4].getblockcount(), 11)
137
138        # Check v1 prefix detection
139        V1_PREFIX = MAGIC_BYTES["regtest"] + b"version\x00\x00\x00\x00\x00"
140        assert_equal(len(V1_PREFIX), 16)
141        with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
142            with self.nodes[0].wait_for_new_peer():
143                s.connect(("127.0.0.1", p2p_port(0)))
144            s.sendall(V1_PREFIX[:-1])
145            assert_equal(self.nodes[0].getpeerinfo()[-1]["transport_protocol_type"], "detecting")
146            s.sendall(bytes([V1_PREFIX[-1]]))  # send out last prefix byte
147            self.wait_until(lambda: self.nodes[0].getpeerinfo()[-1]["transport_protocol_type"] == "v1")
148
149        # Check wrong network prefix detection (hits if the next 12 bytes correspond to a v1 version message)
150        wrong_network_magic_prefix = MAGIC_BYTES["signet"] + V1_PREFIX[4:]
151        with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
152            with self.nodes[0].wait_for_new_peer():
153                s.connect(("127.0.0.1", p2p_port(0)))
154            with self.nodes[0].assert_debug_log(["V2 transport error: V1 peer with wrong MessageStart"], timeout=2):
155                s.sendall(wrong_network_magic_prefix + b"somepayload")
156
157        # Check detection of missing garbage terminator (hits after fixed amount of data if terminator never matches garbage)
158        MAX_KEY_GARB_AND_GARBTERM_LEN = 64 + 4095 + 16
159        with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
160            with self.nodes[0].wait_for_new_peer():
161                s.connect(("127.0.0.1", p2p_port(0)))
162            s.sendall(b'\x00' * (MAX_KEY_GARB_AND_GARBTERM_LEN - 1))
163            self.wait_until(lambda: self.nodes[0].getpeerinfo()[-1]["bytesrecv"] == MAX_KEY_GARB_AND_GARBTERM_LEN - 1)
164            with self.nodes[0].assert_debug_log(["V2 transport error: missing garbage terminator"]):
165                peer_id = self.nodes[0].getpeerinfo()[-1]["id"]
166                s.sendall(b'\x00')  # send out last byte
167                # should disconnect immediately
168                self.wait_until(lambda: peer_id not in [p["id"] for p in self.nodes[0].getpeerinfo()])
169
170
171if __name__ == '__main__':
172    V2TransportTest(__file__).main()
173

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

src/clientversion.cpp

src/common/signmessage.cpp

src/compat/assumptions.h

src/compat/byteswap.h

src/deploymentinfo.cpp

src/deploymentinfo.h

src/deploymentstatus.cpp

src/deploymentstatus.h

src/dummywallet.cpp

src/external_signer.h

src/init/bitcoin-gui.cpp

src/init/bitcoin-node.cpp

src/init/bitcoin-qt.cpp

src/init/bitcoin-wallet.cpp

src/init/bitcoind.cpp

src/init/common.h

src/interfaces/init.h

src/interfaces/ipc.h

src/key_io.h

src/logging/categories.h

src/logging/timer.h

src/mapport.h

src/musig.h

src/net_permissions.h

src/netgroup.h

src/netmessagemaker.h

src/node/chainstatemanager_args.cpp

src/node/connection_types.h

src/node/context.h

src/node/interface_ui.h

src/node/mempool_args.cpp

src/node/mining_args.cpp

src/node/minisketchwrapper.cpp

src/node/txreconciliation.h

src/policy/fees/estimator_args.cpp

src/policy/fees/estimator_args.h

src/policy/fees/estimator_man.cpp

src/policy/fees/estimator_man.h

src/policy/packages.h

src/policy/rbf.h

src/policy/truc_policy.h

src/pow.h

src/primitives/block.cpp

src/randomenv.h

src/rest.h

src/script/keyorigin.h

src/script/parsing.cpp

src/script/parsing.h

src/script/script_error.h

src/script/sigcache.cpp

src/script/sigcache.h

src/script/solver.h

src/script/verify_flags.h

src/semaphore_grant.h

src/signet.h

src/span.h

src/support/allocators/secure.h

src/support/allocators/zeroafterfree.h

src/util/tokenpipe.cpp

src/util/translation.h

src/util/vector.h

src/versionbits.h

src/versionbits_impl.h

src/wallet/external_signer_scriptpubkeyman.h

src/wallet/fees.h

src/wallet/load.h

src/wallet/receive.h

src/wallet/rpc/wallet.h

src/wallet/types.h

src/walletinitinterface.h

src/zmq/zmqabstractnotifier.cpp

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