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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.

9,826 bytes · SHA-256 8ded03aeafd90b7d… · View upstream ↗

1// Copyright (c) 2015-present The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5#include <zmq/zmqpublishnotifier.h>
6
7#include <chain.h>
8#include <crypto/common.h>
9#include <netaddress.h>
10#include <netbase.h>
11#include <primitives/transaction.h>
12#include <serialize.h>
13#include <streams.h>
14#include <uint256.h>
15#include <util/check.h>
16#include <util/log.h>
17#include <zmq/zmqutil.h>
18
19#include <zmq.h>
20
21#include <cstdarg>
22#include <cstddef>
23#include <cstdint>
24#include <cstring>
25#include <map>
26#include <optional>
27#include <string>
28#include <utility>
29#include <vector>
30
31static std::multimap<std::string, CZMQAbstractPublishNotifier*> mapPublishNotifiers;
32
33static const char *MSG_HASHBLOCK = "hashblock";
34static const char *MSG_HASHTX    = "hashtx";
35static const char *MSG_RAWBLOCK  = "rawblock";
36static const char *MSG_RAWTX     = "rawtx";
37static const char *MSG_SEQUENCE  = "sequence";
38
39// Internal function to send multipart message
40static int zmq_send_multipart(void *sock, const void* data, size_t size, ...)
41{
42    va_list args;
43    va_start(args, size);
44
45    while (1)
46    {
47        zmq_msg_t msg;
48
49        int rc = zmq_msg_init_size(&msg, size);
50        if (rc != 0)
51        {
52            zmqError("Unable to initialize ZMQ msg");
53            va_end(args);
54            return -1;
55        }
56
57        void *buf = zmq_msg_data(&msg);
58        memcpy(buf, data, size);
59
60        data = va_arg(args, const void*);
61
62        rc = zmq_msg_send(&msg, sock, data ? ZMQ_SNDMORE : 0);
63        if (rc == -1)
64        {
65            zmqError("Unable to send ZMQ msg");
66            zmq_msg_close(&msg);
67            va_end(args);
68            return -1;
69        }
70
71        zmq_msg_close(&msg);
72
73        if (!data)
74            break;
75
76        size = va_arg(args, size_t);
77    }
78    va_end(args);
79    return 0;
80}
81
82static bool IsZMQAddressIPV6(const std::string &zmq_address)
83{
84    const std::string tcp_prefix = "tcp://";
85    const size_t tcp_index = zmq_address.rfind(tcp_prefix);
86    const size_t colon_index = zmq_address.rfind(':');
87    if (tcp_index == 0 && colon_index != std::string::npos) {
88        const std::string ip = zmq_address.substr(tcp_prefix.length(), colon_index - tcp_prefix.length());
89        const std::optional<CNetAddr> addr{LookupHost(ip, false)};
90        if (addr.has_value() && addr.value().IsIPv6()) return true;
91    }
92    return false;
93}
94
95bool CZMQAbstractPublishNotifier::Initialize(void *pcontext)
96{
97    assert(!psocket);
98
99    // check if address is being used by other publish notifier
100    std::multimap<std::string, CZMQAbstractPublishNotifier*>::iterator i = mapPublishNotifiers.find(address);
101
102    if (i==mapPublishNotifiers.end())
103    {
104        psocket = zmq_socket(pcontext, ZMQ_PUB);
105        if (!psocket)
106        {
107            zmqError("Failed to create socket");
108            return false;
109        }
110
111        LogDebug(BCLog::ZMQ, "Outbound message high water mark for %s at %s is %d\n", type, address, outbound_message_high_water_mark);
112
113        int rc = zmq_setsockopt(psocket, ZMQ_SNDHWM, &outbound_message_high_water_mark, sizeof(outbound_message_high_water_mark));
114        if (rc != 0)
115        {
116            zmqError("Failed to set outbound message high water mark");
117            zmq_close(psocket);
118            return false;
119        }
120
121        const int so_keepalive_option {1};
122        rc = zmq_setsockopt(psocket, ZMQ_TCP_KEEPALIVE, &so_keepalive_option, sizeof(so_keepalive_option));
123        if (rc != 0) {
124            zmqError("Failed to set SO_KEEPALIVE");
125            zmq_close(psocket);
126            return false;
127        }
128
129        // On some systems (e.g. OpenBSD) the ZMQ_IPV6 must not be enabled, if the address to bind isn't IPv6
130        const int enable_ipv6 { IsZMQAddressIPV6(address) ? 1 : 0};
131        rc = zmq_setsockopt(psocket, ZMQ_IPV6, &enable_ipv6, sizeof(enable_ipv6));
132        if (rc != 0) {
133            zmqError("Failed to set ZMQ_IPV6");
134            zmq_close(psocket);
135            return false;
136        }
137
138        rc = zmq_bind(psocket, address.c_str());
139        if (rc != 0)
140        {
141            zmqError("Failed to bind address");
142            zmq_close(psocket);
143            return false;
144        }
145
146        // register this notifier for the address, so it can be reused for other publish notifier
147        mapPublishNotifiers.insert(std::make_pair(address, this));
148        return true;
149    }
150    else
151    {
152        LogDebug(BCLog::ZMQ, "Reusing socket for address %s\n", address);
153        LogDebug(BCLog::ZMQ, "Outbound message high water mark for %s at %s is %d\n", type, address, outbound_message_high_water_mark);
154
155        psocket = i->second->psocket;
156        mapPublishNotifiers.insert(std::make_pair(address, this));
157
158        return true;
159    }
160}
161
162void CZMQAbstractPublishNotifier::Shutdown()
163{
164    // Early return if Initialize was not called
165    if (!psocket) return;
166
167    int count = mapPublishNotifiers.count(address);
168
169    // remove this notifier from the list of publishers using this address
170    typedef std::multimap<std::string, CZMQAbstractPublishNotifier*>::iterator iterator;
171    std::pair<iterator, iterator> iterpair = mapPublishNotifiers.equal_range(address);
172
173    for (iterator it = iterpair.first; it != iterpair.second; ++it)
174    {
175        if (it->second==this)
176        {
177            mapPublishNotifiers.erase(it);
178            break;
179        }
180    }
181
182    if (count == 1)
183    {
184        LogDebug(BCLog::ZMQ, "Close socket at address %s\n", address);
185        int linger = 0;
186        zmq_setsockopt(psocket, ZMQ_LINGER, &linger, sizeof(linger));
187        zmq_close(psocket);
188    }
189
190    psocket = nullptr;
191}
192
193bool CZMQAbstractPublishNotifier::SendZmqMessage(const char *command, const void* data, size_t size)
194{
195    assert(psocket);
196
197    /* send three parts, command & data & a LE 4byte sequence number */
198    unsigned char msgseq[sizeof(uint32_t)];
199    WriteLE32(msgseq, nSequence);
200    int rc = zmq_send_multipart(psocket, command, strlen(command), data, size, msgseq, (size_t)sizeof(uint32_t), nullptr);
201    if (rc == -1)
202        return false;
203
204    /* increment memory only sequence number after sending */
205    nSequence++;
206
207    return true;
208}
209
210bool CZMQPublishHashBlockNotifier::NotifyBlock(const CBlockIndex *pindex)
211{
212    uint256 hash = pindex->GetBlockHash();
213    LogDebug(BCLog::ZMQ, "Publish hashblock %s to %s\n", hash.GetHex(), this->address);
214    uint8_t data[32];
215    for (unsigned int i = 0; i < 32; i++) {
216        data[31 - i] = hash.begin()[i];
217    }
218    return SendZmqMessage(MSG_HASHBLOCK, data, 32);
219}
220
221bool CZMQPublishHashTransactionNotifier::NotifyTransaction(const CTransaction &transaction)
222{
223    uint256 hash = transaction.GetHash().ToUint256();
224    LogDebug(BCLog::ZMQ, "Publish hashtx %s to %s\n", hash.GetHex(), this->address);
225    uint8_t data[32];
226    for (unsigned int i = 0; i < 32; i++) {
227        data[31 - i] = hash.begin()[i];
228    }
229    return SendZmqMessage(MSG_HASHTX, data, 32);
230}
231
232bool CZMQPublishRawBlockNotifier::NotifyBlock(const CBlockIndex *pindex)
233{
234    LogDebug(BCLog::ZMQ, "Publish rawblock %s to %s\n", pindex->GetBlockHash().GetHex(), this->address);
235
236    std::vector<std::byte> block{};
237    if (!m_get_block_by_index(block, *pindex)) {
238        zmqError("Can't read block from disk");
239        return false;
240    }
241
242    return SendZmqMessage(MSG_RAWBLOCK, block.data(), block.size());
243}
244
245bool CZMQPublishRawTransactionNotifier::NotifyTransaction(const CTransaction &transaction)
246{
247    uint256 hash = transaction.GetHash().ToUint256();
248    LogDebug(BCLog::ZMQ, "Publish rawtx %s to %s\n", hash.GetHex(), this->address);
249    DataStream ss;
250    ss << TX_WITH_WITNESS(transaction);

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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