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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) 2019-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 transaction download behavior
7"""
8from decimal import Decimal
9from enum import Enum
10import time
11
12from test_framework.mempool_util import (
13    fill_mempool,
14)
15from test_framework.messages import (
16    CInv,
17    MSG_TX,
18    MSG_TYPE_MASK,
19    MSG_WITNESS_TX,
20    MSG_WTX,
21    msg_inv,
22    msg_notfound,
23    msg_tx,
24)
25from test_framework.p2p import (
26    P2PInterface,
27    p2p_lock,
28    NONPREF_PEER_TX_DELAY,
29    GETDATA_TX_INTERVAL,
30    TXID_RELAY_DELAY,
31    OVERLOADED_PEER_TX_DELAY
32)
33from test_framework.test_framework import BitcoinTestFramework
34from test_framework.util import (
35    assert_equal,
36)
37from test_framework.wallet import MiniWallet
38
39
40class TestP2PConn(P2PInterface):
41    def __init__(self, wtxidrelay=True):
42        super().__init__(wtxidrelay=wtxidrelay)
43        self.tx_getdata_count = 0
44
45    def on_getdata(self, message):
46        for i in message.inv:
47            if i.type & MSG_TYPE_MASK == MSG_TX or i.type & MSG_TYPE_MASK == MSG_WTX:
48                self.tx_getdata_count += 1
49
50
51# Constants from txdownloadman
52MAX_PEER_TX_REQUEST_IN_FLIGHT = 100
53MAX_PEER_TX_ANNOUNCEMENTS = 5000
54
55# Python test constants
56NUM_INBOUND = 10
57MAX_GETDATA_INBOUND_WAIT = GETDATA_TX_INTERVAL + NONPREF_PEER_TX_DELAY + TXID_RELAY_DELAY
58
59class ConnectionType(Enum):
60    """ Different connection types
61    1. INBOUND: Incoming connection, not whitelisted
62    2. OUTBOUND: Outgoing connection
63    3. WHITELIST: Incoming connection, but whitelisted
64    """
65    INBOUND = 0
66    OUTBOUND = 1
67    WHITELIST = 2
68
69class TxDownloadTest(BitcoinTestFramework):
70    def set_test_params(self):
71        self.num_nodes = 2
72        self.extra_args= [['-maxmempool=5', '-persistmempool=0']] * self.num_nodes
73
74    def test_tx_requests(self):
75        self.log.info("Test that we request transactions from all our peers, eventually")
76
77        txid = 0xdeadbeef
78
79        self.log.info("Announce the txid from each incoming peer to node 0")
80        msg = msg_inv([CInv(t=MSG_WTX, h=txid)])
81        for p in self.nodes[0].p2ps:
82            p.send_and_ping(msg)
83
84        outstanding_peer_index = [i for i in range(len(self.nodes[0].p2ps))]
85
86        def getdata_found(peer_index):
87            p = self.nodes[0].p2ps[peer_index]
88            with p2p_lock:
89                return p.last_message.get("getdata") and p.last_message["getdata"].inv[-1].hash == txid
90
91        node_0_mocktime = int(time.time())
92        while outstanding_peer_index:
93            node_0_mocktime += MAX_GETDATA_INBOUND_WAIT
94            self.nodes[0].setmocktime(node_0_mocktime)
95            self.wait_until(lambda: any(getdata_found(i) for i in outstanding_peer_index))
96            for i in outstanding_peer_index:
97                if getdata_found(i):
98                    outstanding_peer_index.remove(i)
99
100        self.nodes[0].setmocktime(0)
101        self.log.info("All outstanding peers received a getdata")
102
103    def test_inv_block(self):
104        self.log.info("Generate a transaction on node 0")
105        tx = self.wallet.create_self_transfer()
106        wtxid = int(tx['wtxid'], 16)
107
108        self.nodes[0].setmocktime(int(time.time()))
109
110        self.log.info(
111            "Announce the transaction to all nodes from all {} incoming peers, but never send it".format(NUM_INBOUND))
112        msg = msg_inv([CInv(t=MSG_WTX, h=wtxid)])
113        for p in self.peers:
114            p.send_and_ping(msg)
115
116        self.log.info("Put the tx in node 0's mempool")
117        self.nodes[0].sendrawtransaction(tx['hex'])
118
119        # Since node 1 is connected outbound to an honest peer (node 0), it
120        # should get the tx within a timeout.
121        # However, node 0 sees the same connection as inbound, so it may not
122        # announce the tx within the timeout.
123        # The timeout is the sum of
124        # * the worst case until the tx is first requested from an inbound
125        #   peer, plus
126        # * the first time it is re-requested from the outbound peer, plus
127        # * 2 seconds to avoid races
128        assert_equal(self.nodes[0].getpeerinfo()[0]["inbound"], True)
129        assert_equal(self.nodes[0].getpeerinfo()[0]["inv_to_send"], 1)
130        assert_equal(self.nodes[1].getpeerinfo()[0]['inbound'], False)
131        timeout = 2 + NONPREF_PEER_TX_DELAY + GETDATA_TX_INTERVAL
132        self.log.info("Tx should be received at node 1 after {} seconds".format(timeout))
133        self.nodes[0].bumpmocktime(timeout)
134        # Use an unrelated peer to ensure node 0 calls `SendMessages` at least once
135        self.nodes[0].p2ps[0].sync_with_ping()
136        assert_equal(self.nodes[0].getpeerinfo()[0]['inv_to_send'], 0)  # May fail rarely, retry the test
137        self.sync_mempools()
138
139        self.nodes[0].setmocktime(0)
140
141    def test_in_flight_max(self):
142        self.log.info("Test that we don't load peers with more than {} transaction requests immediately".format(MAX_PEER_TX_REQUEST_IN_FLIGHT))
143        txids = [i for i in range(MAX_PEER_TX_REQUEST_IN_FLIGHT + 2)]
144
145        p = self.nodes[0].p2ps[0]
146
147        with p2p_lock:
148            p.tx_getdata_count = 0
149
150        mock_time = int(time.time() + 1)
151        self.nodes[0].setmocktime(mock_time)
152        for i in range(MAX_PEER_TX_REQUEST_IN_FLIGHT):
153            p.send_without_ping(msg_inv([CInv(t=MSG_WTX, h=txids[i])]))
154        p.sync_with_ping()
155        mock_time += NONPREF_PEER_TX_DELAY
156        self.nodes[0].setmocktime(mock_time)
157        p.wait_until(lambda: p.tx_getdata_count >= MAX_PEER_TX_REQUEST_IN_FLIGHT)
158        for i in range(MAX_PEER_TX_REQUEST_IN_FLIGHT, len(txids)):
159            p.send_without_ping(msg_inv([CInv(t=MSG_WTX, h=txids[i])]))
160        p.sync_with_ping()
161        self.log.info("No more than {} requests should be seen within {} seconds after announcement".format(MAX_PEER_TX_REQUEST_IN_FLIGHT, NONPREF_PEER_TX_DELAY + OVERLOADED_PEER_TX_DELAY - 1))
162        self.nodes[0].setmocktime(mock_time + NONPREF_PEER_TX_DELAY + OVERLOADED_PEER_TX_DELAY - 1)
163        p.sync_with_ping()
164        with p2p_lock:
165            assert_equal(p.tx_getdata_count, MAX_PEER_TX_REQUEST_IN_FLIGHT)
166        self.log.info("If we wait {} seconds after announcement, we should eventually get more requests".format(NONPREF_PEER_TX_DELAY + OVERLOADED_PEER_TX_DELAY))
167        self.nodes[0].setmocktime(mock_time + NONPREF_PEER_TX_DELAY + OVERLOADED_PEER_TX_DELAY)
168        p.wait_until(lambda: p.tx_getdata_count == len(txids))
169
170    def test_expiry_fallback(self):
171        self.log.info('Check that expiry will select another peer for download')
172        WTXID = 0xffaa
173        peer1 = self.nodes[0].add_p2p_connection(TestP2PConn())
174        peer2 = self.nodes[0].add_p2p_connection(TestP2PConn())
175        for p in [peer1, peer2]:
176            p.send_without_ping(msg_inv([CInv(t=MSG_WTX, h=WTXID)]))
177        # One of the peers is asked for the tx
178        peer2.wait_until(lambda: sum(p.tx_getdata_count for p in [peer1, peer2]) == 1)
179        with p2p_lock:
180            _peer_expiry, peer_fallback = (peer1, peer2) if peer1.tx_getdata_count == 1 else (peer2, peer1)
181            assert_equal(peer_fallback.tx_getdata_count, 0)
182        self.nodes[0].setmocktime(int(time.time()) + GETDATA_TX_INTERVAL + 1)  # Wait for request to _peer_expiry to expire
183        peer_fallback.wait_until(lambda: peer_fallback.tx_getdata_count >= 1, timeout=1)
184        self.restart_node(0)  # reset mocktime
185
186    def test_disconnect_fallback(self):
187        self.log.info('Check that disconnect will select another peer for download')
188        WTXID = 0xffbb
189        peer1 = self.nodes[0].add_p2p_connection(TestP2PConn())
190        peer2 = self.nodes[0].add_p2p_connection(TestP2PConn())
191        for p in [peer1, peer2]:
192            p.send_without_ping(msg_inv([CInv(t=MSG_WTX, h=WTXID)]))
193        # One of the peers is asked for the tx
194        peer2.wait_until(lambda: sum(p.tx_getdata_count for p in [peer1, peer2]) == 1)
195        with p2p_lock:
196            peer_disconnect, peer_fallback = (peer1, peer2) if peer1.tx_getdata_count == 1 else (peer2, peer1)
197            assert_equal(peer_fallback.tx_getdata_count, 0)
198        peer_disconnect.peer_disconnect()
199        peer_disconnect.wait_for_disconnect()
200        peer_fallback.wait_until(lambda: peer_fallback.tx_getdata_count >= 1, timeout=1)
201
202    def test_notfound_fallback(self):
203        self.log.info('Check that notfounds will select another peer for download immediately')
204        WTXID = 0xffdd
205        peer1 = self.nodes[0].add_p2p_connection(TestP2PConn())
206        peer2 = self.nodes[0].add_p2p_connection(TestP2PConn())
207        for p in [peer1, peer2]:
208            p.send_without_ping(msg_inv([CInv(t=MSG_WTX, h=WTXID)]))
209        # One of the peers is asked for the tx
210        peer2.wait_until(lambda: sum(p.tx_getdata_count for p in [peer1, peer2]) == 1)
211        with p2p_lock:
212            peer_notfound, peer_fallback = (peer1, peer2) if peer1.tx_getdata_count == 1 else (peer2, peer1)
213            assert_equal(peer_fallback.tx_getdata_count, 0)
214        peer_notfound.send_and_ping(msg_notfound(vec=[CInv(MSG_WTX, WTXID)]))  # Send notfound, so that fallback peer is selected
215        peer_fallback.wait_until(lambda: peer_fallback.tx_getdata_count >= 1, timeout=1)
216
217    def test_preferred_inv(self, connection_type: ConnectionType):
218        if connection_type == ConnectionType.WHITELIST:
219            self.log.info('Check invs from preferred (whitelisted) peers are downloaded immediately')
220            self.restart_node(0, extra_args=['[email protected]'])
221        elif connection_type == ConnectionType.OUTBOUND:
222            self.log.info('Check invs from preferred (outbound) peers are downloaded immediately')
223            self.restart_node(0)
224        elif connection_type == ConnectionType.INBOUND:
225            self.log.info('Check invs from non-preferred peers are downloaded after {} s'.format(NONPREF_PEER_TX_DELAY))
226            self.restart_node(0)
227        else:
228            raise Exception("invalid connection_type")
229
230        mock_time = int(time.time() + 1)
231        self.nodes[0].setmocktime(mock_time)
232
233        if connection_type == ConnectionType.OUTBOUND:
234            peer = self.nodes[0].add_outbound_p2p_connection(
235               TestP2PConn(), wait_for_verack=True, p2p_idx=1, connection_type="outbound-full-relay")
236        else:
237            peer = self.nodes[0].add_p2p_connection(TestP2PConn())
238
239        peer.send_and_ping(msg_inv([CInv(t=MSG_WTX, h=0xff00ff00)]))
240        if connection_type != ConnectionType.INBOUND:
241            peer.wait_until(lambda: peer.tx_getdata_count >= 1, timeout=1)
242        else:
243            with p2p_lock:
244                assert_equal(peer.tx_getdata_count, 0)
245            self.nodes[0].setmocktime(mock_time + NONPREF_PEER_TX_DELAY)
246            peer.wait_until(lambda: peer.tx_getdata_count >= 1, timeout=1)
247
248    def test_preferred_tiebreaker_inv(self):
249        self.log.info("Test that preferred peers are always selected over non-preferred when ready")
250

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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