Coverage Report

Created: 2025-10-29 16:48

/root/bitcoin/src/consensus/params.h
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// Copyright (c) 2009-2010 Satoshi Nakamoto
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// Copyright (c) 2009-2022 The Bitcoin Core developers
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// Distributed under the MIT software license, see the accompanying
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// file COPYING or http://www.opensource.org/licenses/mit-license.php.
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#ifndef BITCOIN_CONSENSUS_PARAMS_H
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#define BITCOIN_CONSENSUS_PARAMS_H
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#include <script/verify_flags.h>
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#include <uint256.h>
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#include <array>
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#include <chrono>
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#include <limits>
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#include <map>
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#include <vector>
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namespace Consensus {
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/**
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 * A buried deployment is one where the height of the activation has been hardcoded into
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 * the client implementation long after the consensus change has activated. See BIP 90.
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 */
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enum BuriedDeployment : int16_t {
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    // buried deployments get negative values to avoid overlap with DeploymentPos
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    DEPLOYMENT_HEIGHTINCB = std::numeric_limits<int16_t>::min(),
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    DEPLOYMENT_CLTV,
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    DEPLOYMENT_DERSIG,
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    DEPLOYMENT_CSV,
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    DEPLOYMENT_SEGWIT,
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};
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constexpr bool ValidDeployment(BuriedDeployment dep) { return dep <= DEPLOYMENT_SEGWIT; }
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enum DeploymentPos : uint16_t {
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    DEPLOYMENT_TESTDUMMY,
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    DEPLOYMENT_TAPROOT, // Deployment of Schnorr/Taproot (BIPs 340-342)
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    // NOTE: Also add new deployments to VersionBitsDeploymentInfo in deploymentinfo.cpp
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    MAX_VERSION_BITS_DEPLOYMENTS
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};
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constexpr bool ValidDeployment(DeploymentPos dep) { return dep < MAX_VERSION_BITS_DEPLOYMENTS; }
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/**
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 * Struct for each individual consensus rule change using BIP9.
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 */
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struct BIP9Deployment {
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    /** Bit position to select the particular bit in nVersion. */
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    int bit{28};
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    /** Start MedianTime for version bits miner confirmation. Can be a date in the past */
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    int64_t nStartTime{NEVER_ACTIVE};
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    /** Timeout/expiry MedianTime for the deployment attempt. */
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    int64_t nTimeout{NEVER_ACTIVE};
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    /** If lock in occurs, delay activation until at least this block
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     *  height.  Note that activation will only occur on a retarget
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     *  boundary.
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     */
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    int min_activation_height{0};
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    /** Period of blocks to check signalling in (usually retarget period, ie params.DifficultyAdjustmentInterval()) */
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    uint32_t period{2016};
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    /**
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     * Minimum blocks including miner confirmation of the total of 2016 blocks in a retargeting period,
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     * which is also used for BIP9 deployments.
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     * Examples: 1916 for 95%, 1512 for testchains.
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     */
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    uint32_t threshold{1916};
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    /** Constant for nTimeout very far in the future. */
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    static constexpr int64_t NO_TIMEOUT = std::numeric_limits<int64_t>::max();
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    /** Special value for nStartTime indicating that the deployment is always active.
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     *  This is useful for testing, as it means tests don't need to deal with the activation
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     *  process (which takes at least 3 BIP9 intervals). Only tests that specifically test the
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     *  behaviour during activation cannot use this. */
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    static constexpr int64_t ALWAYS_ACTIVE = -1;
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    /** Special value for nStartTime indicating that the deployment is never active.
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     *  This is useful for integrating the code changes for a new feature
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     *  prior to deploying it on some or all networks. */
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    static constexpr int64_t NEVER_ACTIVE = -2;
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};
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/**
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 * Parameters that influence chain consensus.
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 */
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struct Params {
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    uint256 hashGenesisBlock;
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    int nSubsidyHalvingInterval;
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    /**
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     * Hashes of blocks that
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     * - are known to be consensus valid, and
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     * - buried in the chain, and
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     * - fail if the default script verify flags are applied.
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     */
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    std::map<uint256, script_verify_flags> script_flag_exceptions;
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    /** Block height and hash at which BIP34 becomes active */
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    int BIP34Height;
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    uint256 BIP34Hash;
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    /** Block height at which BIP65 becomes active */
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    int BIP65Height;
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    /** Block height at which BIP66 becomes active */
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    int BIP66Height;
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    /** Block height at which CSV (BIP68, BIP112 and BIP113) becomes active */
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    int CSVHeight;
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    /** Block height at which Segwit (BIP141, BIP143 and BIP147) becomes active.
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     * Note that segwit v0 script rules are enforced on all blocks except the
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     * BIP 16 exception blocks. */
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    int SegwitHeight;
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    /** Don't warn about unknown BIP 9 activations below this height.
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     * This prevents us from warning about the CSV and segwit activations. */
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    int MinBIP9WarningHeight;
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    std::array<BIP9Deployment,MAX_VERSION_BITS_DEPLOYMENTS> vDeployments;
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    /** Proof of work parameters */
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    uint256 powLimit;
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    bool fPowAllowMinDifficultyBlocks;
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    /**
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      * Enforce BIP94 timewarp attack mitigation. On testnet4 this also enforces
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      * the block storm mitigation.
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      */
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    bool enforce_BIP94;
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    bool fPowNoRetargeting;
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    int64_t nPowTargetSpacing;
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    int64_t nPowTargetTimespan;
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    std::chrono::seconds PowTargetSpacing() const
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    {
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        return std::chrono::seconds{nPowTargetSpacing};
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    }
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    int64_t DifficultyAdjustmentInterval() const { return nPowTargetTimespan / nPowTargetSpacing; }
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    /** The best chain should have at least this much work */
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    uint256 nMinimumChainWork;
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    /** By default assume that the signatures in ancestors of this block are valid */
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    uint256 defaultAssumeValid;
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    /**
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     * If true, witness commitments contain a payload equal to a Bitcoin Script solution
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     * to the signet challenge. See BIP325.
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     */
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    bool signet_blocks{false};
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    std::vector<uint8_t> signet_challenge;
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    int DeploymentHeight(BuriedDeployment dep) const
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    {
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        switch (dep) {
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        case DEPLOYMENT_HEIGHTINCB:
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            return BIP34Height;
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        case DEPLOYMENT_CLTV:
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            return BIP65Height;
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        case DEPLOYMENT_DERSIG:
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            return BIP66Height;
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        case DEPLOYMENT_CSV:
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            return CSVHeight;
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        case DEPLOYMENT_SEGWIT:
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            return SegwitHeight;
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        } // no default case, so the compiler can warn about missing cases
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        return std::numeric_limits<int>::max();
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    }
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};
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} // namespace Consensus
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#endif // BITCOIN_CONSENSUS_PARAMS_H