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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) 2023-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
6from test_framework.test_framework import BitcoinTestFramework
7from test_framework.messages import (
8    msg_version,
9    msg_filterload
10)
11from test_framework.p2p import (
12    P2PInterface,
13    P2P_SERVICES,
14    P2P_SUBVERSION,
15    P2P_VERSION,
16)
17
18
19class P2PConnectionLimits(BitcoinTestFramework):
20    def set_test_params(self):
21        self.num_nodes = 1
22        # scenario : we have 2 inbound slots and allow a maximum of 1 tx-relaying inbound peer
23        self.extra_args = [['-maxconnections=13']]  # 11 slots are reserved for outbounds, leaving 2 inbound slots
24
25    def run_test(self):
26        self.test_inbound_limits()
27
28    def create_blocks_only_version(self):
29        no_txrelay_version_msg = msg_version()
30        no_txrelay_version_msg.nVersion = P2P_VERSION
31        no_txrelay_version_msg.strSubVer = P2P_SUBVERSION
32        no_txrelay_version_msg.nServices = P2P_SERVICES
33        no_txrelay_version_msg.relay = 0
34        return no_txrelay_version_msg
35
36    def create_no_services_blocks_only_version(self):
37        """VERSION with relay=0 and nServices=0 to avoid block-relay eviction protection."""
38        version_msg = msg_version()
39        version_msg.nVersion = P2P_VERSION
40        version_msg.strSubVer = P2P_SUBVERSION
41        version_msg.nServices = 0
42        version_msg.relay = 0
43        return version_msg
44
45    def test_inbound_limits(self):
46        node = self.nodes[0]
47
48        self.log.info('Test with 2 inbound slots, one of which allows tx-relay')
49        node.add_p2p_connection(P2PInterface())
50
51        self.log.info('Connect a full-relay inbound peer - test that eviction is triggered')
52        # Since there is no unprotected peer to evict here, the new peer is dropped instead.
53        with node.assert_debug_log(['failed to find a tx-relaying eviction candidate - connection dropped'], timeout=2):
54            self.nodes[0].add_p2p_connection(P2PInterface(), expect_success=False, wait_for_verack=False)
55        self.wait_until(lambda: len(node.getpeerinfo()) == 1)
56        node.disconnect_p2ps()
57
58        self.log.info('Connect a block-relay inbound peer - test that second full relay peer is accepted')
59        peer1 = self.nodes[0].add_p2p_connection(P2PInterface(), send_version=False, wait_for_verack=False)
60        peer1.send_without_ping(self.create_blocks_only_version())
61        peer1.wait_for_verack()
62
63        node.add_p2p_connection(P2PInterface())
64        self.wait_until(lambda: len(node.getpeerinfo()) == 2)
65
66        self.log.info('Connecting another full-relay peer triggers non-specific eviction')
67        with node.assert_debug_log(['failed to find an eviction candidate - connection dropped (full)'], timeout=2):
68            self.nodes[0].add_p2p_connection(P2PInterface(), send_version=False, wait_for_verack=False, expect_success=False)
69        self.wait_until(lambda: len(node.getpeerinfo()) == 2)
70
71        self.log.info('Run with bloom filter support and check that a switch to tx relay during runtime can trigger eviction')
72        self.restart_node(0, ['-maxconnections=13', '-peerbloomfilters'])
73        peer1 = self.nodes[0].add_p2p_connection(P2PInterface(), send_version=False, wait_for_verack=False)
74        peer1.send_without_ping(self.create_blocks_only_version())
75        peer1.wait_for_verack()
76
77        node.add_p2p_connection(P2PInterface())
78        self.wait_until(lambda: len(node.getpeerinfo()) == 2)
79        with node.assert_debug_log(['connection dropped after filterload message'], timeout=2):
80            peer1.send_without_ping(msg_filterload(data=b'\xbb'*(100)))
81        self.wait_until(lambda: len(node.getpeerinfo()) == 1)
82
83        self.log.info('Test different values of inboundrelaypercent')
84        self.restart_node(0, ['-maxconnections=13', '-inboundrelaypercent=0'])
85        with node.assert_debug_log(['failed to find a tx-relaying eviction candidate - connection dropped'], timeout=2):
86            self.nodes[0].add_p2p_connection(P2PInterface(), expect_success=False, wait_for_verack=False)
87
88        self.restart_node(0, ['-maxconnections=13', '-inboundrelaypercent=100'])
89        node.add_p2p_connection(P2PInterface())
90        node.add_p2p_connection(P2PInterface())
91        self.wait_until(lambda: len(node.getpeerinfo()) == 2)
92
93        self.log.info('Test that EvictTxPeerIfFull only evicts tx-relaying peers')
94        NUM_BLOCK_RELAY_PEERS = 21
95        self.restart_node(0, ['-maxconnections=33', '-inboundrelaypercent=0'])
96        for _ in range(NUM_BLOCK_RELAY_PEERS):
97            p = self.nodes[0].add_p2p_connection(P2PInterface(), send_version=False, wait_for_verack=False)
98            p.send_without_ping(self.create_no_services_blocks_only_version())
99            p.wait_for_verack()
100        self.wait_until(lambda: len(node.getpeerinfo()) == NUM_BLOCK_RELAY_PEERS)
101
102        with node.assert_debug_log(['failed to find a tx-relaying eviction candidate - connection dropped'], timeout=5):
103            self.nodes[0].add_p2p_connection(P2PInterface(), expect_success=False, wait_for_verack=False)
104        self.wait_until(lambda: len(node.getpeerinfo()) == NUM_BLOCK_RELAY_PEERS)
105
106if __name__ == '__main__':
107    P2PConnectionLimits(__file__).main()
108

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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