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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server340 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.

5,838 bytes · SHA-256 58f92d2bbcae1f60… · View upstream ↗

1// Copyright (c) 2019-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 <signet.h>
6
7#include <consensus/merkle.h>
8#include <consensus/params.h>
9#include <consensus/validation.h>
10#include <primitives/block.h>
11#include <primitives/transaction.h>
12#include <script/interpreter.h>
13#include <script/script.h>
14#include <script/verify_flags.h>
15#include <streams.h>
16#include <uint256.h>
17#include <util/log.h>
18
19#include <algorithm>
20#include <cstddef>
21#include <cstdint>
22#include <exception>
23#include <span>
24#include <utility>
25#include <vector>
26
27static constexpr uint8_t SIGNET_HEADER[4] = {0xec, 0xc7, 0xda, 0xa2};
28
29static constexpr script_verify_flags BLOCK_SCRIPT_VERIFY_FLAGS = SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_WITNESS | SCRIPT_VERIFY_DERSIG | SCRIPT_VERIFY_NULLDUMMY;
30
31static bool FetchAndClearCommitmentSection(const std::span<const uint8_t> header, CScript& witness_commitment, std::vector<uint8_t>& result)
32{
33    CScript replacement;
34    bool found_header = false;
35    result.clear();
36
37    opcodetype opcode;
38    CScript::const_iterator pc = witness_commitment.begin();
39    std::vector<uint8_t> pushdata;
40    while (witness_commitment.GetOp(pc, opcode, pushdata)) {
41        if (pushdata.size() > 0) {
42            if (!found_header && pushdata.size() > header.size() && std::ranges::equal(std::span{pushdata}.first(header.size()), header)) {
43                // pushdata only counts if it has the header _and_ some data
44                result.insert(result.end(), pushdata.begin() + header.size(), pushdata.end());
45                pushdata.erase(pushdata.begin() + header.size(), pushdata.end());
46                found_header = true;
47            }
48            replacement << pushdata;
49        } else {
50            replacement << opcode;
51        }
52    }
53
54    if (found_header) witness_commitment = replacement;
55    return found_header;
56}
57
58static uint256 ComputeModifiedMerkleRoot(const CMutableTransaction& cb, const CBlock& block)
59{
60    std::vector<uint256> leaves;
61    leaves.reserve((block.vtx.size() + 1) & ~1ULL); // capacity rounded up to even
62    leaves.push_back(cb.GetHash().ToUint256());
63    for (size_t s = 1; s < block.vtx.size(); ++s) {
64        leaves.push_back(block.vtx[s]->GetHash().ToUint256());
65    }
66    return ComputeMerkleRoot(std::move(leaves));
67}
68
69std::optional<SignetTxs> SignetTxs::Create(const CBlock& block, const CScript& challenge)
70{
71    CMutableTransaction tx_to_spend;
72    tx_to_spend.version = 0;
73    tx_to_spend.nLockTime = 0;
74    tx_to_spend.vin.emplace_back(COutPoint(), CScript(OP_0), 0);
75    tx_to_spend.vout.emplace_back(0, challenge);
76
77    CMutableTransaction tx_spending;
78    tx_spending.version = 0;
79    tx_spending.nLockTime = 0;
80    tx_spending.vin.emplace_back(COutPoint(), CScript(), 0);
81    tx_spending.vout.emplace_back(0, CScript(OP_RETURN));
82
83    // can't fill any other fields before extracting signet
84    // responses from block coinbase tx
85
86    // find and delete signet signature
87    if (block.vtx.empty()) return std::nullopt; // no coinbase tx in block; invalid
88    CMutableTransaction modified_cb(*block.vtx.at(0));
89
90    const int cidx = GetWitnessCommitmentIndex(block);
91    if (cidx == NO_WITNESS_COMMITMENT) {
92        return std::nullopt; // require a witness commitment
93    }
94
95    CScript& witness_commitment = modified_cb.vout.at(cidx).scriptPubKey;
96
97    std::vector<uint8_t> signet_solution;
98    if (!FetchAndClearCommitmentSection(SIGNET_HEADER, witness_commitment, signet_solution)) {
99        // no signet solution -- allow this to support OP_TRUE as trivial block challenge
100    } else {
101        try {
102            SpanReader v{signet_solution};
103            v >> tx_spending.vin[0].scriptSig;
104            v >> tx_spending.vin[0].scriptWitness.stack;
105            if (!v.empty()) return std::nullopt; // extraneous data encountered
106        } catch (const std::exception&) {
107            return std::nullopt; // parsing error
108        }
109    }
110    uint256 signet_merkle = ComputeModifiedMerkleRoot(modified_cb, block);
111
112    std::vector<uint8_t> block_data;
113    VectorWriter writer{block_data, 0};
114    writer << block.nVersion;
115    writer << block.hashPrevBlock;
116    writer << signet_merkle;
117    writer << block.nTime;
118    tx_to_spend.vin[0].scriptSig << block_data;
119    tx_spending.vin[0].prevout = COutPoint(tx_to_spend.GetHash(), 0);
120
121    return SignetTxs{tx_to_spend, tx_spending};
122}
123
124// Signet block solution checker
125bool CheckSignetBlockSolution(const CBlock& block, const Consensus::Params& consensusParams)
126{
127    if (block.GetHash() == consensusParams.hashGenesisBlock) {
128        // genesis block solution is always valid
129        return true;
130    }
131
132    const CScript challenge(consensusParams.signet_challenge.begin(), consensusParams.signet_challenge.end());
133    const std::optional<SignetTxs> signet_txs = SignetTxs::Create(block, challenge);
134
135    if (!signet_txs) {
136        LogDebug(BCLog::VALIDATION, "CheckSignetBlockSolution: Errors in block (block solution parse failure)\n");
137        return false;
138    }
139
140    const CScript& scriptSig = signet_txs->m_to_sign.vin[0].scriptSig;
141    const CScriptWitness& witness = signet_txs->m_to_sign.vin[0].scriptWitness;
142
143    PrecomputedTransactionData txdata;
144    txdata.Init(signet_txs->m_to_sign, {signet_txs->m_to_spend.vout[0]});
145    TransactionSignatureChecker sigcheck(&signet_txs->m_to_sign, /* nInIn= */ 0, /* amountIn= */ signet_txs->m_to_spend.vout[0].nValue, txdata, MissingDataBehavior::ASSERT_FAIL);
146
147    if (!VerifyScript(scriptSig, signet_txs->m_to_spend.vout[0].scriptPubKey, &witness, BLOCK_SCRIPT_VERIFY_FLAGS, sigcheck)) {
148        LogDebug(BCLog::VALIDATION, "CheckSignetBlockSolution: Errors in block (block solution invalid)\n");
149        return false;
150    }
151    return true;
152}
153

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

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