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1#!/usr/bin/env python3
2# Copyright (c) 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 transaction relay rate limiting via token buckets.
6
7With -txsendrate=R, the inbound count bucket has capacity R*30. A broadcast
8transaction is relayed immediately while the bucket has tokens; once it is
9exhausted the excess transactions queue in a global backlog and drain as the
10bucket refills (R tokens/second as mocktime advances).
11"""
12
13from decimal import Decimal
14import time
15
16from test_framework.blocktools import COINBASE_MATURITY
17from test_framework.p2p import P2PTxInvStore
18from test_framework.test_framework import BitcoinTestFramework
19from test_framework.util import assert_equal
20from test_framework.wallet import MiniWallet
21
22SEND_RATE = 2                 # -txsendrate value
23BUCKET_CAP = SEND_RATE * 30   # count bucket capacity (60)
24NUM_TXS = 80                  # total transactions to submit
25
26
27class TxRelayRateLimitTest(BitcoinTestFramework):
28    def set_test_params(self):
29        self.num_nodes = 1
30        self.extra_args = [[f'-txsendrate={SEND_RATE}']]
31
32    def inbound_backlog(self, node):
33        return node.getnetworkinfo()['inv_buckets']['inbound']['backlog']
34
35    def run_test(self):
36        node = self.nodes[0]
37        wallet = MiniWallet(node)
38
39        node.setmocktime(int(time.time()))
40
41        # Mine enough blocks for mature coinbase UTXOs.
42        self.generate(wallet, COINBASE_MATURITY + NUM_TXS + 50)
43
44        # Connect an inbound peer (negotiates wtxid relay by default)
45        peer = node.add_p2p_connection(P2PTxInvStore())
46
47        # Advance time so the peer's trickle timer initializes
48        node.bumpmocktime(10)
49        peer.sync_with_ping()
50        assert_equal(len(peer.get_invs()), 0)
51
52        # Verify the configured send rate
53        assert_equal(node.getnetworkinfo()['tx_send_rate'], SEND_RATE)
54
55        self.test_rate_limit_and_rbf(node, wallet, peer)
56
57    def test_rate_limit_and_rbf(self, node, wallet, peer):
58        self.log.info(f"Submitting {NUM_TXS} transactions at frozen time (bucket capacity {BUCKET_CAP})")
59
60        # Prepare an RBF pair: original and replacement spending the same UTXO.
61        # Both are created upfront so we can submit the replacement later.
62        rbf_utxo = wallet.get_utxo()
63        tx_rbf_orig = wallet.create_self_transfer(utxo_to_spend=rbf_utxo)
64        tx_rbf_repl = wallet.create_self_transfer(utxo_to_spend=rbf_utxo, fee_rate=Decimal("0.009"))
65
66        # Submit NUM_TXS transactions at frozen time. Each broadcast is relayed
67        # immediately while the count bucket has tokens, so the first BUCKET_CAP
68        # are handed straight to the peer and the rest queue in the backlog. The
69        # RBF original is placed in the backlogged tail.
70        RBF_INDEX = NUM_TXS - 5
71        for i in range(NUM_TXS):
72            if i == RBF_INDEX:
73                node.sendrawtransaction(tx_rbf_orig['hex'])
74            else:
75                wallet.send_self_transfer(from_node=node)
76
77        # The excess beyond the bucket capacity is backlogged. Nothing is
78        # announced yet -- the per-peer trickle timer hasn't fired (frozen time).
79        self.log.info(f"Backlog after burst: {self.inbound_backlog(node)}")
80        assert_equal(self.inbound_backlog(node), NUM_TXS - BUCKET_CAP)
81        assert_equal(len(peer.get_invs()), 0)
82
83        # RBF the backlogged original while time is still frozen, so the
84        # replacement also queues in the backlog (the bucket is exhausted). The
85        # original's wtxid stays in the backlog vector for now but is dropped
86        # when the backlog is processed, since it is no longer in the mempool.
87        self.log.info("RBF'ing a backlogged transaction")
88        node.sendrawtransaction(tx_rbf_repl['hex'])
89        assert_equal(self.inbound_backlog(node), NUM_TXS - BUCKET_CAP + 1)
90
91        # Advance time so the bucket refills and the backlog drains. Loop until
92        # the backlog is empty and every surviving tx has trickled out.
93        self.log.info("Advancing time to drain the backlog")
94        for _ in range(30):
95            if self.inbound_backlog(node) == 0 and len(peer.get_invs()) == NUM_TXS:
96                break
97            node.bumpmocktime(4)
98            peer.sync_with_ping()
99
100        announced = set(peer.get_invs())
101        self.log.info(f"Total announced: {len(announced)}")
102
103        # Every surviving transaction is announced: the burst minus the dropped
104        # RBF original, plus the replacement.
105        assert_equal(self.inbound_backlog(node), 0)
106        assert_equal(len(announced), NUM_TXS)
107        assert int(tx_rbf_orig['wtxid'], 16) not in announced
108        assert int(tx_rbf_repl['wtxid'], 16) in announced
109
110        self.log.info("Rate limiting and RBF backlog cleanup test passed")
111
112
113if __name__ == '__main__':
114    TxRelayRateLimitTest(__file__).main()
115

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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