thehub/libs/utils/primitives/ScriptDefines.h

/*
 * This file is part of the Flowee project
 * Copyright (C) 2009-2010 Satoshi Nakamoto
 * Copyright (C) 2009-2015 The Bitcoin Core developers
 * Copyright (C) 2021 Tom Zander <tom@flowee.org>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef FLOWEE_SCRIPT_DEFINES_H
#define FLOWEE_SCRIPT_DEFINES_H

#include <cstdint>

// Maximum number of bytes pushable to the stack before CHIP-2025-05 VM limits.
static const unsigned int MAX_SCRIPT_ELEMENT_SIZE_LEGACY = 520;
static const unsigned int MAX_SCRIPT_ELEMENT_SIZE = MAX_SCRIPT_ELEMENT_SIZE_LEGACY;

// Maximum number of non-push operations per script before CHIP-2021-05 VM limits.
static const int MAX_OPS_PER_SCRIPT_LEGACY = 201;
static const int MAX_OPS_PER_SCRIPT = MAX_OPS_PER_SCRIPT_LEGACY;

// Maximum script length in bytes.
static const int MAX_SCRIPT_SIZE = 10000;

// Maximum number of values on the stack plus altstack plus function table.
static const int MAX_STACK_SIZE = 1000;

// Maximum number of public keys per multisig
static const int MAX_PUBKEYS_PER_MULTISIG = 20;

// Threshold for nLockTime: below this value it is interpreted as block number,
// otherwise as UNIX timestamp.
static const unsigned int LOCKTIME_THRESHOLD = 500000000; // Tue Nov  5 00:53:20 1985 UTC

namespace may2025 {

static const unsigned int MAX_SCRIPT_ELEMENT_SIZE = MAX_SCRIPT_SIZE;
static const unsigned int OPCODE_COST = 100;
static const unsigned int MAX_CONDITIONAL_STACK_DEPTH = 100;
static const unsigned int SIG_CHECK_COST_FACTOR = 26000;

namespace detail {
static const unsigned int HASH_ITER_BONUS_FOR_NONSTD_TXNS = 7;
static const unsigned int OP_COST_BUDGET_PER_INPUT_BYTE = 800;
static const unsigned int HASH_COST_PENALTY_FOR_STD_TXNS = 3;
static const unsigned int HASH_BLOCK_SIZE = 64;
static const unsigned int INPUT_SCRIPT_SIZE_FIXED_CREDIT = 41;

inline int64_t GetInputHashItersLimit(bool standard, uint64_t scriptSigSize) noexcept
{
    const unsigned int factor = standard ? 1 : HASH_ITER_BONUS_FOR_NONSTD_TXNS;
    return static_cast<int64_t>((scriptSigSize + INPUT_SCRIPT_SIZE_FIXED_CREDIT) * factor / 2);
}

inline int64_t GetInputOpCostLimit(uint64_t scriptSigSize) noexcept
{
    return static_cast<int64_t>(scriptSigSize + INPUT_SCRIPT_SIZE_FIXED_CREDIT) * OP_COST_BUDGET_PER_INPUT_BYTE;
}
} // namespace detail

inline int64_t GetHashIterOpCostFactor(bool standard) noexcept
{
    return standard ? detail::HASH_BLOCK_SIZE * detail::HASH_COST_PENALTY_FOR_STD_TXNS
                    : detail::HASH_BLOCK_SIZE;
}

inline int64_t CalcHashIters(uint32_t messageLength, bool isTwoRoundHashOp) noexcept
{
    return static_cast<int64_t>(isTwoRoundHashOp) + 1 +
        ((static_cast<uint64_t>(messageLength) + 8) / detail::HASH_BLOCK_SIZE);
}

} // namespace may2025

namespace may2026 {
static const unsigned int MAX_FUNCTION_IDENTIFIER_SIZE = 7;
static const unsigned int MAX_CONTROL_STACK_DEPTH = may2025::MAX_CONDITIONAL_STACK_DEPTH;
} // namespace may2026


#endif