Initial Vexta Core v0.1.0 release

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Capri 2026-07-15 14:07:28 +00:00
commit 25c454329d
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// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2020 The Bitcoin Core developers
// Copyright (c) 2014-2020 The DigiByte Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef DIGIBYTE_CONSENSUS_CONSENSUS_H
#define DIGIBYTE_CONSENSUS_CONSENSUS_H
#include <stdlib.h>
#include <stdint.h>
/** The maximum allowed size for a serialized block, in bytes (only for buffer size limits) */
static const unsigned int MAX_BLOCK_SERIALIZED_SIZE = 4000000;
/** The maximum allowed weight for a block, see BIP 141 (network rule) */
static const unsigned int MAX_BLOCK_WEIGHT = 4000000;
/** The maximum allowed number of signature check operations in a block (network rule) */
static const int64_t MAX_BLOCK_SIGOPS_COST = 80000;
/** Coinbase transaction outputs can only be spent after this number of new blocks (network rule) */
static const int COINBASE_MATURITY = 8;
static const int COINBASE_MATURITY_2 = 100;
/** The maximum allowed number of signature check operations in a block (network rule) */
static const int WITNESS_SCALE_FACTOR = 4;
static const size_t MIN_TRANSACTION_WEIGHT = WITNESS_SCALE_FACTOR * 60; // 60 is the lower bound for the size of a valid serialized CTransaction
static const size_t MIN_SERIALIZABLE_TRANSACTION_WEIGHT = WITNESS_SCALE_FACTOR * 10; // 10 is the lower bound for the size of a serialized CTransaction
/** Flags for nSequence and nLockTime locks */
/** Interpret sequence numbers as relative lock-time constraints. */
static constexpr unsigned int LOCKTIME_VERIFY_SEQUENCE = (1 << 0);
/** Use GetMedianTimePast() instead of nTime for end point timestamp. */
static constexpr unsigned int LOCKTIME_MEDIAN_TIME_PAST = (1 << 1);
#endif // DIGIBYTE_CONSENSUS_CONSENSUS_H

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// Copyright (c) 2009-2020 The Bitcoin Core developers
// Copyright (c) 2014-2020 The DigiByte Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include <consensus/merkle.h>
#include <hash.h>
/* WARNING! If you're reading this because you're learning about crypto
and/or designing a new system that will use merkle trees, keep in mind
that the following merkle tree algorithm has a serious flaw related to
duplicate txids, resulting in a vulnerability (CVE-2012-2459).
The reason is that if the number of hashes in the list at a given level
is odd, the last one is duplicated before computing the next level (which
is unusual in Merkle trees). This results in certain sequences of
transactions leading to the same merkle root. For example, these two
trees:
A A
/ \ / \
B C B C
/ \ | / \ / \
D E F D E F F
/ \ / \ / \ / \ / \ / \ / \
1 2 3 4 5 6 1 2 3 4 5 6 5 6
for transaction lists [1,2,3,4,5,6] and [1,2,3,4,5,6,5,6] (where 5 and
6 are repeated) result in the same root hash A (because the hash of both
of (F) and (F,F) is C).
The vulnerability results from being able to send a block with such a
transaction list, with the same merkle root, and the same block hash as
the original without duplication, resulting in failed validation. If the
receiving node proceeds to mark that block as permanently invalid
however, it will fail to accept further unmodified (and thus potentially
valid) versions of the same block. We defend against this by detecting
the case where we would hash two identical hashes at the end of the list
together, and treating that identically to the block having an invalid
merkle root. Assuming no double-SHA256 collisions, this will detect all
known ways of changing the transactions without affecting the merkle
root.
*/
uint256 ComputeMerkleRoot(std::vector<uint256> hashes, bool* mutated) {
bool mutation = false;
while (hashes.size() > 1) {
if (mutated) {
for (size_t pos = 0; pos + 1 < hashes.size(); pos += 2) {
if (hashes[pos] == hashes[pos + 1]) mutation = true;
}
}
if (hashes.size() & 1) {
hashes.push_back(hashes.back());
}
SHA256D64(hashes[0].begin(), hashes[0].begin(), hashes.size() / 2);
hashes.resize(hashes.size() / 2);
}
if (mutated) *mutated = mutation;
if (hashes.size() == 0) return uint256();
return hashes[0];
}
uint256 BlockMerkleRoot(const CBlock& block, bool* mutated)
{
std::vector<uint256> leaves;
leaves.resize(block.vtx.size());
for (size_t s = 0; s < block.vtx.size(); s++) {
leaves[s] = block.vtx[s]->GetHash();
}
return ComputeMerkleRoot(std::move(leaves), mutated);
}
uint256 BlockWitnessMerkleRoot(const CBlock& block, bool* mutated)
{
std::vector<uint256> leaves;
leaves.resize(block.vtx.size());
leaves[0].SetNull(); // The witness hash of the coinbase is 0.
for (size_t s = 1; s < block.vtx.size(); s++) {
leaves[s] = block.vtx[s]->GetWitnessHash();
}
return ComputeMerkleRoot(std::move(leaves), mutated);
}

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// Copyright (c) 2009-2020 The Bitcoin Core developers
// Copyright (c) 2014-2020 The DigiByte Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef DIGIBYTE_CONSENSUS_MERKLE_H
#define DIGIBYTE_CONSENSUS_MERKLE_H
#include <vector>
#include <primitives/block.h>
#include <uint256.h>
uint256 ComputeMerkleRoot(std::vector<uint256> hashes, bool* mutated = nullptr);
/*
* Compute the Merkle root of the transactions in a block.
* *mutated is set to true if a duplicated subtree was found.
*/
uint256 BlockMerkleRoot(const CBlock& block, bool* mutated = nullptr);
/*
* Compute the Merkle root of the witness transactions in a block.
* *mutated is set to true if a duplicated subtree was found.
*/
uint256 BlockWitnessMerkleRoot(const CBlock& block, bool* mutated = nullptr);
#endif // DIGIBYTE_CONSENSUS_MERKLE_H

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// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2020 The Bitcoin Core developers
// Copyright (c) 2026 The Vexta Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef DIGIBYTE_CONSENSUS_PARAMS_H
#define DIGIBYTE_CONSENSUS_PARAMS_H
#include <uint256.h>
#include <limits>
#include <map>
namespace Consensus {
/**
* A buried deployment is one where the height of the activation has been hardcoded into
* the client implementation long after the consensus change has activated. See BIP 90.
*/
enum BuriedDeployment : int16_t {
// buried deployments get negative values to avoid overlap with DeploymentPos
DEPLOYMENT_HEIGHTINCB = std::numeric_limits<int16_t>::min(),
DEPLOYMENT_CLTV,
DEPLOYMENT_DERSIG,
DEPLOYMENT_CSV, // Deployment of BIP68, BIP112, and BIP113.
DEPLOYMENT_SEGWIT, // Deployment of BIP141, BIP143, and BIP147.
DEPLOYMENT_NVERSIONBIPS, // Deployment of BIP34, BIP65, and BIP66.
//DEPLOYMENT_EQUIHASH, // Equihash algo swap
//DEPLOYMENT_ETHASH, // Ethash algo swap
};
enum DeploymentPos : uint16_t {
DEPLOYMENT_TESTDUMMY,
DEPLOYMENT_TAPROOT, // Deployment of Schnorr/Taproot (BIPs 340-342)
// NOTE: Also add new deployments to VersionBitsDeploymentInfo in deploymentinfo.cpp
MAX_VERSION_BITS_DEPLOYMENTS
};
constexpr bool ValidDeployment(BuriedDeployment dep) { return dep <= DEPLOYMENT_NVERSIONBIPS; }
constexpr bool ValidDeployment(DeploymentPos dep) { return DEPLOYMENT_TESTDUMMY <= dep && dep <= DEPLOYMENT_TAPROOT; }
/**
* Struct for each individual consensus rule change using BIP9.
*/
struct BIP9Deployment {
/** Bit position to select the particular bit in nVersion. */
int bit;
/** Start MedianTime for version bits miner confirmation. Can be a date in the past */
int64_t nStartTime;
/** Timeout/expiry MedianTime for the deployment attempt. */
int64_t nTimeout;
/** If lock in occurs, delay activation until at least this block
* height. Note that activation will only occur on a retarget
* boundary.
*/
int min_activation_height{0};
/** Constant for nTimeout very far in the future. */
static constexpr int64_t NO_TIMEOUT = std::numeric_limits<int64_t>::max();
/** Special value for nStartTime indicating that the deployment is always active.
* This is useful for testing, as it means tests don't need to deal with the activation
* process (which takes at least 3 BIP9 intervals). Only tests that specifically test the
* behaviour during activation cannot use this. */
static constexpr int64_t ALWAYS_ACTIVE = -1;
/** Special value for nStartTime indicating that the deployment is never active.
* This is useful for integrating the code changes for a new feature
* prior to deploying it on some or all networks. */
static constexpr int64_t NEVER_ACTIVE = -2;
};
/**
* Parameters that influence chain consensus.
*/
struct Params {
uint256 hashGenesisBlock;
int nSubsidyHalvingInterval;
/* Block hash that is excepted from BIP16 enforcement */
uint256 BIP16Exception;
/** Block height and hash at which BIP34 becomes active */
int BIP34Height;
uint256 BIP34Hash;
/** Block height at which BIP65 becomes active */
int BIP65Height;
/** Block height at which BIP66 becomes active */
int BIP66Height;
/** Block height at which CSV (BIP68, BIP112 and BIP113) becomes active */
int CSVHeight;
/** Block height at which Segwit (BIP141, BIP143 and BIP147) becomes active.
* Note that segwit v0 script rules are enforced on all blocks except the
* BIP 16 exception blocks. */
int SegwitHeight;
/**
* Block height at which version bits were set to resolved
* to support future algo changes */
/**
* Legacy reserved deployment activation height */
/** Don't warn about unknown BIP 9 activations below this height.
* This prevents us from warning about the CSV and segwit activations. */
int MinBIP9WarningHeight;
/**
* Minimum blocks including miner confirmation of the total of 2016 blocks in a retargeting period,
* Examples: 1916 for 95%, 1512 for testchains.
*/
uint32_t nRuleChangeActivationThreshold;
uint32_t nMinerConfirmationWindow;
BIP9Deployment vDeployments[MAX_VERSION_BITS_DEPLOYMENTS];
/** Proof of work parameters */
uint256 powLimit;
bool fPowAllowMinDifficultyBlocks;
bool fEasyPow;
bool fPowNoRetargeting;
bool fRbfEnabled;
int64_t nPowTargetSpacing;
int64_t difficultyAveragingWindow;
int64_t difficultyTargetTimespan;
int64_t difficultyMinActualTimespan;
int64_t difficultyMaxActualTimespan;
/** The best chain should have at least this much work */
uint256 nMinimumChainWork;
/** By default assume that the signatures in ancestors of this block are valid */
uint256 defaultAssumeValid;
/**
* If true, witness commitments contain a payload equal to a signet challenge solution
* to the signet challenge. See BIP325.
*/
bool signet_blocks{false};
std::vector<uint8_t> signet_challenge;
bool EnableRBF() const { return fRbfEnabled; }
int DeploymentHeight(BuriedDeployment dep) const
{
switch (dep) {
case DEPLOYMENT_HEIGHTINCB:
return BIP34Height;
case DEPLOYMENT_CLTV:
return BIP65Height;
case DEPLOYMENT_DERSIG:
return BIP66Height;
case DEPLOYMENT_CSV:
return CSVHeight;
case DEPLOYMENT_SEGWIT:
return SegwitHeight;
case DEPLOYMENT_NVERSIONBIPS:
// In Vexta DEPLOYMENT_CSV and DEPLOYMENT_NVERSIONBIPS
// got activated simultaneously
return CSVHeight;
} // no default case, so the compiler can warn about missing cases
return std::numeric_limits<int>::max();
}
};
} // namespace Consensus
#endif // DIGIBYTE_CONSENSUS_PARAMS_H

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// Copyright (c) 2017-2019 The DigiByte Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include <consensus/tx_check.h>
#include <primitives/transaction.h>
#include <consensus/validation.h>
bool CheckTransaction(const CTransaction& tx, TxValidationState& state)
{
// Basic checks that don't depend on any context
if (tx.vin.empty())
return state.Invalid(TxValidationResult::TX_CONSENSUS, "bad-txns-vin-empty");
if (tx.vout.empty())
return state.Invalid(TxValidationResult::TX_CONSENSUS, "bad-txns-vout-empty");
// Size limits (this doesn't take the witness into account, as that hasn't been checked for malleability)
if (::GetSerializeSize(tx, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) * WITNESS_SCALE_FACTOR > MAX_BLOCK_WEIGHT)
return state.Invalid(TxValidationResult::TX_CONSENSUS, "bad-txns-oversize");
// Check for negative or overflow output values (see CVE-2010-5139)
CAmount nValueOut = 0;
for (const auto& txout : tx.vout)
{
if (txout.nValue < 0)
return state.Invalid(TxValidationResult::TX_CONSENSUS, "bad-txns-vout-negative");
if (txout.nValue > MAX_MONEY)
return state.Invalid(TxValidationResult::TX_CONSENSUS, "bad-txns-vout-toolarge");
nValueOut += txout.nValue;
if (!MoneyRange(nValueOut))
return state.Invalid(TxValidationResult::TX_CONSENSUS, "bad-txns-txouttotal-toolarge");
}
// Check for duplicate inputs (see CVE-2018-17144)
// While Consensus::CheckTxInputs does check if all inputs of a tx are available, and UpdateCoins marks all inputs
// of a tx as spent, it does not check if the tx has duplicate inputs.
// Failure to run this check will result in either a crash or an inflation bug, depending on the implementation of
// the underlying coins database.
std::set<COutPoint> vInOutPoints;
for (const auto& txin : tx.vin) {
if (!vInOutPoints.insert(txin.prevout).second)
return state.Invalid(TxValidationResult::TX_CONSENSUS, "bad-txns-inputs-duplicate");
}
if (tx.IsCoinBase())
{
if (tx.vin[0].scriptSig.size() < 2 || tx.vin[0].scriptSig.size() > 100)
return state.Invalid(TxValidationResult::TX_CONSENSUS, "bad-cb-length");
}
else
{
for (const auto& txin : tx.vin)
if (txin.prevout.IsNull())
return state.Invalid(TxValidationResult::TX_CONSENSUS, "bad-txns-prevout-null");
}
return true;
}

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// Copyright (c) 2017-2019 The DigiByte Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef DIGIBYTE_CONSENSUS_TX_CHECK_H
#define DIGIBYTE_CONSENSUS_TX_CHECK_H
/**
* Context-independent transaction checking code that can be called outside the
* Vexta server and doesn't depend on chain or mempool state. Transaction
* verification code that does call server functions or depend on server state
* belongs in tx_verify.h/cpp instead.
*/
class CTransaction;
class TxValidationState;
bool CheckTransaction(const CTransaction& tx, TxValidationState& state);
#endif // DIGIBYTE_CONSENSUS_TX_CHECK_H

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// Copyright (c) 2017-2020 The Bitcoin Core developers
// Copyright (c) 2017-2020 The DigiByte Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include <consensus/tx_verify.h>
#include <consensus/consensus.h>
#include <primitives/transaction.h>
#include <script/interpreter.h>
#include <consensus/validation.h>
// TODO remove the following dependencies
#include <chain.h>
#include <coins.h>
#include <util/moneystr.h>
bool IsFinalTx(const CTransaction &tx, int nBlockHeight, int64_t nBlockTime)
{
if (tx.nLockTime == 0)
return true;
if ((int64_t)tx.nLockTime < ((int64_t)tx.nLockTime < LOCKTIME_THRESHOLD ? (int64_t)nBlockHeight : nBlockTime))
return true;
// Even if tx.nLockTime isn't satisfied by nBlockHeight/nBlockTime, a
// transaction is still considered final if all inputs' nSequence ==
// SEQUENCE_FINAL (0xffffffff), in which case nLockTime is ignored.
//
// Because of this behavior OP_CHECKLOCKTIMEVERIFY/CheckLockTime() will
// also check that the spending input's nSequence != SEQUENCE_FINAL,
// ensuring that an unsatisfied nLockTime value will actually cause
// IsFinalTx() to return false here:
for (const auto& txin : tx.vin) {
if (!(txin.nSequence == CTxIn::SEQUENCE_FINAL))
return false;
}
return true;
}
std::pair<int, int64_t> CalculateSequenceLocks(const CTransaction &tx, int flags, std::vector<int>& prevHeights, const CBlockIndex& block)
{
assert(prevHeights.size() == tx.vin.size());
// Will be set to the equivalent height- and time-based nLockTime
// values that would be necessary to satisfy all relative lock-
// time constraints given our view of block chain history.
// The semantics of nLockTime are the last invalid height/time, so
// use -1 to have the effect of any height or time being valid.
int nMinHeight = -1;
int64_t nMinTime = -1;
// tx.nVersion is signed integer so requires cast to unsigned otherwise
// we would be doing a signed comparison and half the range of nVersion
// wouldn't support BIP 68.
bool fEnforceBIP68 = static_cast<uint32_t>(tx.nVersion) >= 2
&& flags & LOCKTIME_VERIFY_SEQUENCE;
// Do not enforce sequence numbers as a relative lock time
// unless we have been instructed to
if (!fEnforceBIP68) {
return std::make_pair(nMinHeight, nMinTime);
}
for (size_t txinIndex = 0; txinIndex < tx.vin.size(); txinIndex++) {
const CTxIn& txin = tx.vin[txinIndex];
// Sequence numbers with the most significant bit set are not
// treated as relative lock-times, nor are they given any
// consensus-enforced meaning at this point.
if (txin.nSequence & CTxIn::SEQUENCE_LOCKTIME_DISABLE_FLAG) {
// The height of this input is not relevant for sequence locks
prevHeights[txinIndex] = 0;
continue;
}
int nCoinHeight = prevHeights[txinIndex];
if (txin.nSequence & CTxIn::SEQUENCE_LOCKTIME_TYPE_FLAG) {
int64_t nCoinTime = block.GetAncestor(std::max(nCoinHeight-1, 0))->GetMedianTimePast();
// NOTE: Subtract 1 to maintain nLockTime semantics
// BIP 68 relative lock times have the semantics of calculating
// the first block or time at which the transaction would be
// valid. When calculating the effective block time or height
// for the entire transaction, we switch to using the
// semantics of nLockTime which is the last invalid block
// time or height. Thus we subtract 1 from the calculated
// time or height.
// Time-based relative lock-times are measured from the
// smallest allowed timestamp of the block containing the
// txout being spent, which is the median time past of the
// block prior.
nMinTime = std::max(nMinTime, nCoinTime + (int64_t)((txin.nSequence & CTxIn::SEQUENCE_LOCKTIME_MASK) << CTxIn::SEQUENCE_LOCKTIME_GRANULARITY) - 1);
} else {
nMinHeight = std::max(nMinHeight, nCoinHeight + (int)(txin.nSequence & CTxIn::SEQUENCE_LOCKTIME_MASK) - 1);
}
}
return std::make_pair(nMinHeight, nMinTime);
}
bool EvaluateSequenceLocks(const CBlockIndex& block, std::pair<int, int64_t> lockPair)
{
assert(block.pprev);
int64_t nBlockTime = block.pprev->GetMedianTimePast();
if (lockPair.first >= block.nHeight || lockPair.second >= nBlockTime)
return false;
return true;
}
bool SequenceLocks(const CTransaction &tx, int flags, std::vector<int>& prevHeights, const CBlockIndex& block)
{
return EvaluateSequenceLocks(block, CalculateSequenceLocks(tx, flags, prevHeights, block));
}
unsigned int GetLegacySigOpCount(const CTransaction& tx)
{
unsigned int nSigOps = 0;
for (const auto& txin : tx.vin)
{
nSigOps += txin.scriptSig.GetSigOpCount(false);
}
for (const auto& txout : tx.vout)
{
nSigOps += txout.scriptPubKey.GetSigOpCount(false);
}
return nSigOps;
}
unsigned int GetP2SHSigOpCount(const CTransaction& tx, const CCoinsViewCache& inputs)
{
if (tx.IsCoinBase())
return 0;
unsigned int nSigOps = 0;
for (unsigned int i = 0; i < tx.vin.size(); i++)
{
const Coin& coin = inputs.AccessCoin(tx.vin[i].prevout);
assert(!coin.IsSpent());
const CTxOut &prevout = coin.out;
if (prevout.scriptPubKey.IsPayToScriptHash())
nSigOps += prevout.scriptPubKey.GetSigOpCount(tx.vin[i].scriptSig);
}
return nSigOps;
}
int64_t GetTransactionSigOpCost(const CTransaction& tx, const CCoinsViewCache& inputs, int flags)
{
int64_t nSigOps = GetLegacySigOpCount(tx) * WITNESS_SCALE_FACTOR;
if (tx.IsCoinBase())
return nSigOps;
if (flags & SCRIPT_VERIFY_P2SH) {
nSigOps += GetP2SHSigOpCount(tx, inputs) * WITNESS_SCALE_FACTOR;
}
for (unsigned int i = 0; i < tx.vin.size(); i++)
{
const Coin& coin = inputs.AccessCoin(tx.vin[i].prevout);
assert(!coin.IsSpent());
const CTxOut &prevout = coin.out;
nSigOps += CountWitnessSigOps(tx.vin[i].scriptSig, prevout.scriptPubKey, &tx.vin[i].scriptWitness, flags);
}
return nSigOps;
}
bool Consensus::CheckTxInputs(const CTransaction& tx, TxValidationState& state, const CCoinsViewCache& inputs, int nSpendHeight, CAmount& txfee)
{
// are the actual inputs available?
if (!inputs.HaveInputs(tx)) {
return state.Invalid(TxValidationResult::TX_MISSING_INPUTS, "bad-txns-inputs-missingorspent",
strprintf("%s: inputs missing/spent", __func__));
}
CAmount nValueIn = 0;
for (unsigned int i = 0; i < tx.vin.size(); ++i) {
const COutPoint &prevout = tx.vin[i].prevout;
const Coin& coin = inputs.AccessCoin(prevout);
assert(!coin.IsSpent());
// If prev is coinbase, check that it's matured
if (coin.IsCoinBase() && nSpendHeight - coin.nHeight < (coin.nHeight < 145000 ? COINBASE_MATURITY : COINBASE_MATURITY_2)) {
return state.Invalid(TxValidationResult::TX_PREMATURE_SPEND, "bad-txns-premature-spend-of-coinbase",
strprintf("tried to spend coinbase at depth %d", nSpendHeight - coin.nHeight));
}
// Check for negative or overflow input values
nValueIn += coin.out.nValue;
if (!MoneyRange(coin.out.nValue) || !MoneyRange(nValueIn)) {
return state.Invalid(TxValidationResult::TX_CONSENSUS, "bad-txns-inputvalues-outofrange");
}
}
const CAmount value_out = tx.GetValueOut();
if (nValueIn < value_out) {
return state.Invalid(TxValidationResult::TX_CONSENSUS, "bad-txns-in-belowout",
strprintf("value in (%s) < value out (%s)", FormatMoney(nValueIn), FormatMoney(value_out)));
}
// Tally transaction fees
const CAmount txfee_aux = nValueIn - value_out;
if (!MoneyRange(txfee_aux)) {
return state.Invalid(TxValidationResult::TX_CONSENSUS, "bad-txns-fee-outofrange");
}
txfee = txfee_aux;
return true;
}

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// Copyright (c) 2009-2020 The Bitcoin Core developers
// Copyright (c) 2014-2020 The DigiByte Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef DIGIBYTE_CONSENSUS_TX_VERIFY_H
#define DIGIBYTE_CONSENSUS_TX_VERIFY_H
#include <amount.h>
#include <stdint.h>
#include <vector>
class CBlockIndex;
class CCoinsViewCache;
class CTransaction;
class TxValidationState;
/** Transaction validation functions */
namespace Consensus {
/**
* Check whether all inputs of this transaction are valid (no double spends and amounts)
* This does not modify the UTXO set. This does not check scripts and sigs.
* @param[out] txfee Set to the transaction fee if successful.
* Preconditions: tx.IsCoinBase() is false.
*/
[[nodiscard]] bool CheckTxInputs(const CTransaction& tx, TxValidationState& state, const CCoinsViewCache& inputs, int nSpendHeight, CAmount& txfee);
} // namespace Consensus
/** Auxiliary functions for transaction validation (ideally should not be exposed) */
/**
* Count ECDSA signature operations the old-fashioned (pre-0.6) way
* @return number of sigops this transaction's outputs will produce when spent
* @see CTransaction::FetchInputs
*/
unsigned int GetLegacySigOpCount(const CTransaction& tx);
/**
* Count ECDSA signature operations in pay-to-script-hash inputs.
*
* @param[in] mapInputs Map of previous transactions that have outputs we're spending
* @return maximum number of sigops required to validate this transaction's inputs
* @see CTransaction::FetchInputs
*/
unsigned int GetP2SHSigOpCount(const CTransaction& tx, const CCoinsViewCache& mapInputs);
/**
* Compute total signature operation cost of a transaction.
* @param[in] tx Transaction for which we are computing the cost
* @param[in] inputs Map of previous transactions that have outputs we're spending
* @param[out] flags Script verification flags
* @return Total signature operation cost of tx
*/
int64_t GetTransactionSigOpCost(const CTransaction& tx, const CCoinsViewCache& inputs, int flags);
/**
* Check if transaction is final and can be included in a block with the
* specified height and time. Consensus critical.
*/
bool IsFinalTx(const CTransaction &tx, int nBlockHeight, int64_t nBlockTime);
/**
* Calculates the block height and previous block's median time past at
* which the transaction will be considered final in the context of BIP 68.
* Also removes from the vector of input heights any entries which did not
* correspond to sequence locked inputs as they do not affect the calculation.
*/
std::pair<int, int64_t> CalculateSequenceLocks(const CTransaction &tx, int flags, std::vector<int>& prevHeights, const CBlockIndex& block);
bool EvaluateSequenceLocks(const CBlockIndex& block, std::pair<int, int64_t> lockPair);
/**
* Check if transaction is final per BIP 68 sequence numbers and can be included in a block.
* Consensus critical. Takes as input a list of heights at which tx's inputs (in order) confirmed.
*/
bool SequenceLocks(const CTransaction &tx, int flags, std::vector<int>& prevHeights, const CBlockIndex& block);
#endif // DIGIBYTE_CONSENSUS_TX_VERIFY_H

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// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2020 The Bitcoin Core developers
// Copyright (c) 2014-2020 The DigiByte Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef DIGIBYTE_CONSENSUS_VALIDATION_H
#define DIGIBYTE_CONSENSUS_VALIDATION_H
#include <string>
#include <version.h>
#include <consensus/consensus.h>
#include <primitives/transaction.h>
#include <primitives/block.h>
/** Index marker for when no witness commitment is present in a coinbase transaction. */
static constexpr int NO_WITNESS_COMMITMENT{-1};
/** Minimum size of a witness commitment structure. Defined in BIP 141. **/
static constexpr size_t MINIMUM_WITNESS_COMMITMENT{38};
/** A "reason" why a transaction was invalid, suitable for determining whether the
* provider of the transaction should be banned/ignored/disconnected/etc.
*/
enum class TxValidationResult {
TX_RESULT_UNSET = 0, //!< initial value. Tx has not yet been rejected
TX_CONSENSUS, //!< invalid by consensus rules
/**
* Invalid by a change to consensus rules more recent than SegWit.
* Currently unused as there are no such consensus rule changes, and any download
* sources realistically need to support SegWit in order to provide useful data,
* so differentiating between always-invalid and invalid-by-pre-SegWit-soft-fork
* is uninteresting.
*/
TX_RECENT_CONSENSUS_CHANGE,
TX_INPUTS_NOT_STANDARD, //!< inputs (covered by txid) failed policy rules
TX_NOT_STANDARD, //!< otherwise didn't meet our local policy rules
TX_MISSING_INPUTS, //!< transaction was missing some of its inputs
TX_PREMATURE_SPEND, //!< transaction spends a coinbase too early, or violates locktime/sequence locks
/**
* Transaction might have a witness prior to SegWit
* activation, or witness may have been malleated (which includes
* non-standard witnesses).
*/
TX_WITNESS_MUTATED,
/**
* Transaction is missing a witness.
*/
TX_WITNESS_STRIPPED,
/**
* Tx already in mempool or conflicts with a tx in the chain
* (if it conflicts with another tx in mempool, we use MEMPOOL_POLICY as it failed to reach the RBF threshold)
* Currently this is only used if the transaction already exists in the mempool or on chain.
*/
TX_CONFLICT,
TX_MEMPOOL_POLICY, //!< violated mempool's fee/size/descendant/RBF/etc limits
};
/** A "reason" why a block was invalid, suitable for determining whether the
* provider of the block should be banned/ignored/disconnected/etc.
* These are much more granular than the rejection codes, which may be more
* useful for some other use-cases.
*/
enum class BlockValidationResult {
BLOCK_RESULT_UNSET = 0, //!< initial value. Block has not yet been rejected
BLOCK_CONSENSUS, //!< invalid by consensus rules (excluding any below reasons)
/**
* Invalid by a change to consensus rules more recent than SegWit.
* Currently unused as there are no such consensus rule changes, and any download
* sources realistically need to support SegWit in order to provide useful data,
* so differentiating between always-invalid and invalid-by-pre-SegWit-soft-fork
* is uninteresting.
*/
BLOCK_RECENT_CONSENSUS_CHANGE,
BLOCK_CACHED_INVALID, //!< this block was cached as being invalid and we didn't store the reason why
BLOCK_INVALID_HEADER, //!< invalid proof of work or time too old
BLOCK_MUTATED, //!< the block's data didn't match the data committed to by the PoW
BLOCK_MISSING_PREV, //!< We don't have the previous block the checked one is built on
BLOCK_INVALID_PREV, //!< A block this one builds on is invalid
BLOCK_TIME_FUTURE, //!< block timestamp was > 2 hours in the future (or our clock is bad)
BLOCK_CHECKPOINT, //!< the block failed to meet one of our checkpoints
};
/** Template for capturing information about block/transaction validation. This is instantiated
* by TxValidationState and BlockValidationState for validation information on transactions
* and blocks respectively. */
template <typename Result>
class ValidationState
{
private:
enum class ModeState {
M_VALID, //!< everything ok
M_INVALID, //!< network rule violation (DoS value may be set)
M_ERROR, //!< run-time error
} m_mode{ModeState::M_VALID};
Result m_result{};
std::string m_reject_reason;
std::string m_debug_message;
public:
bool Invalid(Result result,
const std::string& reject_reason = "",
const std::string& debug_message = "")
{
m_result = result;
m_reject_reason = reject_reason;
m_debug_message = debug_message;
if (m_mode != ModeState::M_ERROR) m_mode = ModeState::M_INVALID;
return false;
}
bool Error(const std::string& reject_reason)
{
if (m_mode == ModeState::M_VALID)
m_reject_reason = reject_reason;
m_mode = ModeState::M_ERROR;
return false;
}
bool IsValid() const { return m_mode == ModeState::M_VALID; }
bool IsInvalid() const { return m_mode == ModeState::M_INVALID; }
bool IsError() const { return m_mode == ModeState::M_ERROR; }
Result GetResult() const { return m_result; }
std::string GetRejectReason() const { return m_reject_reason; }
std::string GetDebugMessage() const { return m_debug_message; }
std::string ToString() const
{
if (IsValid()) {
return "Valid";
}
if (!m_debug_message.empty()) {
return m_reject_reason + ", " + m_debug_message;
}
return m_reject_reason;
}
};
class TxValidationState : public ValidationState<TxValidationResult> {};
class BlockValidationState : public ValidationState<BlockValidationResult> {};
// These implement the weight = (stripped_size * 4) + witness_size formula,
// using only serialization with and without witness data. As witness_size
// is equal to total_size - stripped_size, this formula is identical to:
// weight = (stripped_size * 3) + total_size.
static inline int64_t GetTransactionWeight(const CTransaction& tx)
{
return ::GetSerializeSize(tx, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) * (WITNESS_SCALE_FACTOR - 1) + ::GetSerializeSize(tx, PROTOCOL_VERSION);
}
static inline int64_t GetBlockWeight(const CBlock& block)
{
return ::GetSerializeSize(block, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) * (WITNESS_SCALE_FACTOR - 1) + ::GetSerializeSize(block, PROTOCOL_VERSION);
}
static inline int64_t GetTransactionInputWeight(const CTxIn& txin)
{
// scriptWitness size is added here because witnesses and txins are split up in segwit serialization.
return ::GetSerializeSize(txin, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) * (WITNESS_SCALE_FACTOR - 1) + ::GetSerializeSize(txin, PROTOCOL_VERSION) + ::GetSerializeSize(txin.scriptWitness.stack, PROTOCOL_VERSION);
}
/** Compute at which vout of the block's coinbase transaction the witness commitment occurs, or -1 if not found */
inline int GetWitnessCommitmentIndex(const CBlock& block)
{
int commitpos = NO_WITNESS_COMMITMENT;
if (!block.vtx.empty()) {
for (size_t o = 0; o < block.vtx[0]->vout.size(); o++) {
const CTxOut& vout = block.vtx[0]->vout[o];
if (vout.scriptPubKey.size() >= MINIMUM_WITNESS_COMMITMENT &&
vout.scriptPubKey[0] == OP_RETURN &&
vout.scriptPubKey[1] == 0x24 &&
vout.scriptPubKey[2] == 0xaa &&
vout.scriptPubKey[3] == 0x21 &&
vout.scriptPubKey[4] == 0xa9 &&
vout.scriptPubKey[5] == 0xed) {
commitpos = o;
}
}
}
return commitpos;
}
#endif // DIGIBYTE_CONSENSUS_VALIDATION_H