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

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13,020 bytes · SHA-256 4394f6fdf7656e0e… · View upstream ↗

1// Copyright (c) 2016-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 <consensus/params.h>
6#include <deploymentinfo.h>
7#include <kernel/chainparams.h>
8#include <util/check.h>
9#include <versionbits.h>
10#include <versionbits_impl.h>
11
12using enum ThresholdState;
13
14std::string StateName(ThresholdState state)
15{
16    switch (state) {
17    case DEFINED: return "defined";
18    case STARTED: return "started";
19    case LOCKED_IN: return "locked_in";
20    case ACTIVE: return "active";
21    case FAILED: return "failed";
22    }
23    return "invalid";
24}
25
26ThresholdState AbstractThresholdConditionChecker::GetStateFor(const CBlockIndex* pindexPrev, ThresholdConditionCache& cache) const
27{
28    int nPeriod = Period();
29    int nThreshold = Threshold();
30    int min_activation_height = MinActivationHeight();
31    int64_t nTimeStart = BeginTime();
32    int64_t nTimeTimeout = EndTime();
33
34    // Check if this deployment is always active.
35    if (nTimeStart == Consensus::BIP9Deployment::ALWAYS_ACTIVE) {
36        return ThresholdState::ACTIVE;
37    }
38
39    // Check if this deployment is never active.
40    if (nTimeStart == Consensus::BIP9Deployment::NEVER_ACTIVE) {
41        return ThresholdState::FAILED;
42    }
43
44    // A block's state is always the same as that of the first of its period, so it is computed based on a pindexPrev whose height equals a multiple of nPeriod - 1.
45    if (pindexPrev != nullptr) {
46        pindexPrev = pindexPrev->GetAncestor(pindexPrev->nHeight - ((pindexPrev->nHeight + 1) % nPeriod));
47    }
48
49    // Walk backwards in steps of nPeriod to find a pindexPrev whose information is known
50    std::vector<const CBlockIndex*> vToCompute;
51    while (!cache.contains(pindexPrev)) {
52        if (pindexPrev == nullptr) {
53            // The genesis block is by definition defined.
54            cache[pindexPrev] = ThresholdState::DEFINED;
55            break;
56        }
57        if (pindexPrev->GetMedianTimePast() < nTimeStart) {
58            // Optimization: don't recompute down further, as we know every earlier block will be before the start time
59            cache[pindexPrev] = ThresholdState::DEFINED;
60            break;
61        }
62        vToCompute.push_back(pindexPrev);
63        pindexPrev = pindexPrev->GetAncestor(pindexPrev->nHeight - nPeriod);
64    }
65
66    // At this point, cache[pindexPrev] is known
67    assert(cache.contains(pindexPrev));
68    ThresholdState state = cache[pindexPrev];
69
70    // Now walk forward and compute the state of descendants of pindexPrev
71    while (!vToCompute.empty()) {
72        ThresholdState stateNext = state;
73        pindexPrev = vToCompute.back();
74        vToCompute.pop_back();
75
76        switch (state) {
77            case ThresholdState::DEFINED: {
78                if (pindexPrev->GetMedianTimePast() >= nTimeStart) {
79                    stateNext = ThresholdState::STARTED;
80                }
81                break;
82            }
83            case ThresholdState::STARTED: {
84                // We need to count
85                const CBlockIndex* pindexCount = pindexPrev;
86                int count = 0;
87                for (int i = 0; i < nPeriod; i++) {
88                    if (Condition(pindexCount)) {
89                        count++;
90                    }
91                    pindexCount = pindexCount->pprev;
92                }
93                if (count >= nThreshold) {
94                    stateNext = ThresholdState::LOCKED_IN;
95                } else if (pindexPrev->GetMedianTimePast() >= nTimeTimeout) {
96                    stateNext = ThresholdState::FAILED;
97                }
98                break;
99            }
100            case ThresholdState::LOCKED_IN: {
101                // Progresses into ACTIVE provided activation height will have been reached.
102                if (pindexPrev->nHeight + 1 >= min_activation_height) {
103                    stateNext = ThresholdState::ACTIVE;
104                }
105                break;
106            }
107            case ThresholdState::FAILED:
108            case ThresholdState::ACTIVE: {
109                // Nothing happens, these are terminal states.
110                break;
111            }
112        }
113        cache[pindexPrev] = state = stateNext;
114    }
115
116    return state;
117}
118
119BIP9Stats AbstractThresholdConditionChecker::GetStateStatisticsFor(const CBlockIndex* pindex, std::vector<bool>* signalling_blocks) const
120{
121    BIP9Stats stats = {};
122
123    stats.period = Period();
124    stats.threshold = Threshold();
125
126    if (pindex == nullptr) return stats;
127
128    // Find how many blocks are in the current period
129    int blocks_in_period = 1 + (pindex->nHeight % stats.period);
130
131    // Reset signalling_blocks
132    if (signalling_blocks) {
133        signalling_blocks->assign(blocks_in_period, false);
134    }
135
136    // Count from current block to beginning of period
137    int elapsed = 0;
138    int count = 0;
139    const CBlockIndex* currentIndex = pindex;
140    do {
141        ++elapsed;
142        --blocks_in_period;
143        if (Condition(currentIndex)) {
144            ++count;
145            if (signalling_blocks) signalling_blocks->at(blocks_in_period) = true;
146        }
147        currentIndex = currentIndex->pprev;
148    } while(blocks_in_period > 0);
149
150    stats.elapsed = elapsed;
151    stats.count = count;
152    stats.possible = (stats.period - stats.threshold ) >= (stats.elapsed - count);
153
154    return stats;
155}
156
157int AbstractThresholdConditionChecker::GetStateSinceHeightFor(const CBlockIndex* pindexPrev, ThresholdConditionCache& cache) const
158{
159    int64_t start_time = BeginTime();
160    if (start_time == Consensus::BIP9Deployment::ALWAYS_ACTIVE || start_time == Consensus::BIP9Deployment::NEVER_ACTIVE) {
161        return 0;
162    }
163
164    const ThresholdState initialState = GetStateFor(pindexPrev, cache);
165
166    // BIP 9 about state DEFINED: "The genesis block is by definition in this state for each deployment."
167    if (initialState == ThresholdState::DEFINED) {
168        return 0;
169    }
170
171    const int nPeriod = Period();
172
173    // A block's state is always the same as that of the first of its period, so it is computed based on a pindexPrev whose height equals a multiple of nPeriod - 1.
174    // To ease understanding of the following height calculation, it helps to remember that
175    // right now pindexPrev points to the block prior to the block that we are computing for, thus:
176    // if we are computing for the last block of a period, then pindexPrev points to the second to last block of the period, and
177    // if we are computing for the first block of a period, then pindexPrev points to the last block of the previous period.
178    // The parent of the genesis block is represented by nullptr.
179    pindexPrev = Assert(pindexPrev->GetAncestor(pindexPrev->nHeight - ((pindexPrev->nHeight + 1) % nPeriod)));
180
181    const CBlockIndex* previousPeriodParent = pindexPrev->GetAncestor(pindexPrev->nHeight - nPeriod);
182
183    while (previousPeriodParent != nullptr && GetStateFor(previousPeriodParent, cache) == initialState) {
184        pindexPrev = previousPeriodParent;
185        previousPeriodParent = pindexPrev->GetAncestor(pindexPrev->nHeight - nPeriod);
186    }
187
188    // Adjust the result because right now we point to the parent block.
189    return pindexPrev->nHeight + 1;
190}
191
192BIP9Info VersionBitsCache::Info(const CBlockIndex& block_index, const Consensus::Params& params, Consensus::DeploymentPos id)
193{
194    BIP9Info result;
195
196    VersionBitsConditionChecker checker(params, id);
197
198    ThresholdState current_state, next_state;
199
200    {
201        LOCK(m_mutex);
202        current_state = checker.GetStateFor(block_index.pprev, m_caches[id]);
203        next_state = checker.GetStateFor(&block_index, m_caches[id]);
204        result.since = checker.GetStateSinceHeightFor(block_index.pprev, m_caches[id]);
205    }
206
207    result.current_state = StateName(current_state);
208    result.next_state = StateName(next_state);
209
210    const bool has_signal = (STARTED == current_state || LOCKED_IN == current_state);
211    if (has_signal) {
212        result.stats.emplace(checker.GetStateStatisticsFor(&block_index, &result.signalling_blocks));
213        if (LOCKED_IN == current_state) {
214            result.stats->threshold = 0;
215            result.stats->possible = false;
216        }
217    }
218
219    if (current_state == ACTIVE) {
220        result.active_since = result.since;
221    } else if (next_state == ACTIVE) {
222        result.active_since = block_index.nHeight + 1;
223    }
224
225    return result;
226}
227
228BIP9GBTStatus VersionBitsCache::GBTStatus(const CBlockIndex& block_index, const Consensus::Params& params)
229{
230    BIP9GBTStatus result;
231
232    LOCK(m_mutex);
233    for (int i = 0; i < (int)Consensus::MAX_VERSION_BITS_DEPLOYMENTS; i++) {
234        auto pos = static_cast<Consensus::DeploymentPos>(i);
235        VersionBitsConditionChecker checker(params, pos);
236        ThresholdState state = checker.GetStateFor(&block_index, m_caches[pos]);
237        const VBDeploymentInfo& vbdepinfo = VersionBitsDeploymentInfo[pos];
238        BIP9GBTStatus::Info gbtinfo{.bit=params.vDeployments[pos].bit, .mask=checker.Mask(), .gbt_optional_rule=vbdepinfo.gbt_optional_rule};
239
240        switch (state) {
241        case DEFINED:
242        case FAILED:
243            // Not exposed to GBT
244            break;
245        case STARTED:
246            result.signalling.try_emplace(vbdepinfo.name, gbtinfo);
247            break;
248        case LOCKED_IN:
249            result.locked_in.try_emplace(vbdepinfo.name, gbtinfo);
250            break;

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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