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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"""Test ThreadDNSAddressSeed logic for querying DNS seeds."""
6
7import itertools
8
9from test_framework.netutil import UNREACHABLE_PROXY_ARG
10from test_framework.p2p import P2PInterface
11from test_framework.test_framework import BitcoinTestFramework
12
13
14class P2PDNSSeeds(BitcoinTestFramework):
15    def set_test_params(self):
16        self.setup_clean_chain = True
17        self.num_nodes = 1
18        self.extra_args = [["-dnsseed=1", UNREACHABLE_PROXY_ARG]]
19
20    def run_test(self):
21        self.init_arg_tests()
22        self.existing_outbound_connections_test()
23        self.existing_block_relay_connections_test()
24        self.force_dns_test()
25        self.wait_time_tests()
26
27    def init_arg_tests(self):
28        fakeaddr = "fakenodeaddr.fakedomain.invalid."
29
30        self.log.info("Check that setting -connect disables -dnsseed by default")
31        self.nodes[0].stop_node()
32        with self.nodes[0].assert_debug_log(expected_msgs=["DNS seeding disabled"], timeout=2):
33            self.start_node(0, extra_args=[f"-connect={fakeaddr}", UNREACHABLE_PROXY_ARG])
34
35        self.log.info("Check that running -connect and -dnsseed means DNS logic runs.")
36        with self.nodes[0].assert_debug_log(expected_msgs=["Loading addresses from DNS seed"], timeout=12):
37            self.restart_node(0, extra_args=[f"-connect={fakeaddr}", "-dnsseed=1", UNREACHABLE_PROXY_ARG])
38
39        self.log.info("Check that running -forcednsseed and -dnsseed=0 throws an error.")
40        self.nodes[0].stop_node()
41        self.nodes[0].assert_start_raises_init_error(
42            expected_msg="Error: Cannot set -forcednsseed to true when setting -dnsseed to false.",
43            extra_args=["-forcednsseed=1", "-dnsseed=0"],
44        )
45
46        self.log.info("Check that running -forcednsseed and -connect throws an error.")
47        # -connect soft sets -dnsseed to false, so throws the same error
48        self.nodes[0].stop_node()
49        self.nodes[0].assert_start_raises_init_error(
50            expected_msg="Error: Cannot set -forcednsseed to true when setting -dnsseed to false.",
51            extra_args=["-forcednsseed=1", f"-connect={fakeaddr}"],
52        )
53
54        # Restore default bitcoind settings
55        self.restart_node(0)
56
57    def existing_outbound_connections_test(self):
58        # Make sure addrman is populated to enter the conditional where we
59        # delay and potentially skip DNS seeding.
60        self.nodes[0].addpeeraddress("192.0.0.8", 8333)
61
62        self.log.info("Check that we *do not* query DNS seeds if we have 2 outbound connections")
63
64        self.restart_node(0)
65        with self.nodes[0].assert_debug_log(expected_msgs=["P2P peers available. Skipped DNS seeding."], timeout=12):
66            for i in range(2):
67                self.nodes[0].add_outbound_p2p_connection(P2PInterface(), p2p_idx=i, connection_type="outbound-full-relay")
68
69    def existing_block_relay_connections_test(self):
70        # Make sure addrman is populated to enter the conditional where we
71        # delay and potentially skip DNS seeding. No-op when run after
72        # existing_outbound_connections_test.
73        self.nodes[0].addpeeraddress("192.0.0.8", 8333)
74
75        self.log.info("Check that we *do* query DNS seeds if we only have 2 block-relay-only connections")
76
77        self.restart_node(0)
78        with self.nodes[0].assert_debug_log(expected_msgs=["Loading addresses from DNS seed"], timeout=12):
79            # This mimics the "anchors" logic where nodes are likely to
80            # reconnect to block-relay-only connections on startup.
81            # Since we do not participate in addr relay with these connections,
82            # we still want to query the DNS seeds.
83            for i in range(2):
84                self.nodes[0].add_outbound_p2p_connection(P2PInterface(), p2p_idx=i, connection_type="block-relay-only")
85
86    def force_dns_test(self):
87        self.log.info("Check that we query DNS seeds if -forcednsseed param is set")
88
89        with self.nodes[0].assert_debug_log(expected_msgs=["Loading addresses from DNS seed"], timeout=12):
90            # -dnsseed defaults to 1 in bitcoind, but 0 in the test framework,
91            # so pass it explicitly here
92            self.restart_node(0, ["-forcednsseed", "-dnsseed=1", UNREACHABLE_PROXY_ARG])
93
94        # Restore default for subsequent tests
95        self.restart_node(0)
96
97    def wait_time_tests(self):
98        self.log.info("Check the delay before querying DNS seeds")
99
100        # Populate addrman with < 1000 addresses
101        for i in range(5):
102            a = f"192.0.0.{i}"
103            self.nodes[0].addpeeraddress(a, 8333)
104
105        # The delay should be 11 seconds
106        with self.nodes[0].assert_debug_log(expected_msgs=["Waiting 11 seconds before querying DNS seeds.\n"], timeout=2):
107            self.restart_node(0)
108
109        # Populate addrman with > 1000 addresses
110        for i in itertools.count():
111            first_octet = i % 2 + 1
112            second_octet = i % 256
113            third_octet = i % 100
114            a = f"{first_octet}.{second_octet}.{third_octet}.1"
115            self.nodes[0].addpeeraddress(a, 8333)
116            if (i > 1000 and i % 100 == 0):
117                # The addrman size is non-deterministic because new addresses
118                # are sorted into buckets, potentially displacing existing
119                # addresses. Periodically check if we have met the desired
120                # threshold.
121                if len(self.nodes[0].getnodeaddresses(0)) > 1000:
122                    break
123
124        # The delay should be 5 mins
125        with self.nodes[0].assert_debug_log(expected_msgs=["Waiting 300 seconds before querying DNS seeds.\n"], timeout=2):
126            self.restart_node(0)
127
128
129if __name__ == '__main__':
130    P2PDNSSeeds(__file__).main()
131

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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