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-rw-r--r--src/wallet/spend.cpp499
1 files changed, 245 insertions, 254 deletions
diff --git a/src/wallet/spend.cpp b/src/wallet/spend.cpp
index 97fc7acca5..c8ded4c51e 100644
--- a/src/wallet/spend.cpp
+++ b/src/wallet/spend.cpp
@@ -352,7 +352,7 @@ std::vector<OutputGroup> CWallet::GroupOutputs(const std::vector<COutput>& outpu
return groups_out;
}
-bool CWallet::SelectCoinsMinConf(const CAmount& nTargetValue, const CoinEligibilityFilter& eligibility_filter, std::vector<COutput> coins,
+bool CWallet::AttemptSelection(const CAmount& nTargetValue, const CoinEligibilityFilter& eligibility_filter, std::vector<COutput> coins,
std::set<CInputCoin>& setCoinsRet, CAmount& nValueRet, const CoinSelectionParams& coin_selection_params) const
{
setCoinsRet.clear();
@@ -456,32 +456,32 @@ bool CWallet::SelectCoins(const std::vector<COutput>& vAvailableCoins, const CAm
// If possible, fund the transaction with confirmed UTXOs only. Prefer at least six
// confirmations on outputs received from other wallets and only spend confirmed change.
- if (SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(1, 6, 0), vCoins, setCoinsRet, nValueRet, coin_selection_params)) return true;
- if (SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(1, 1, 0), vCoins, setCoinsRet, nValueRet, coin_selection_params)) return true;
+ if (AttemptSelection(value_to_select, CoinEligibilityFilter(1, 6, 0), vCoins, setCoinsRet, nValueRet, coin_selection_params)) return true;
+ if (AttemptSelection(value_to_select, CoinEligibilityFilter(1, 1, 0), vCoins, setCoinsRet, nValueRet, coin_selection_params)) return true;
// Fall back to using zero confirmation change (but with as few ancestors in the mempool as
// possible) if we cannot fund the transaction otherwise.
if (m_spend_zero_conf_change) {
- if (SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(0, 1, 2), vCoins, setCoinsRet, nValueRet, coin_selection_params)) return true;
- if (SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(0, 1, std::min((size_t)4, max_ancestors/3), std::min((size_t)4, max_descendants/3)),
+ if (AttemptSelection(value_to_select, CoinEligibilityFilter(0, 1, 2), vCoins, setCoinsRet, nValueRet, coin_selection_params)) return true;
+ if (AttemptSelection(value_to_select, CoinEligibilityFilter(0, 1, std::min((size_t)4, max_ancestors/3), std::min((size_t)4, max_descendants/3)),
vCoins, setCoinsRet, nValueRet, coin_selection_params)) {
return true;
}
- if (SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(0, 1, max_ancestors/2, max_descendants/2),
+ if (AttemptSelection(value_to_select, CoinEligibilityFilter(0, 1, max_ancestors/2, max_descendants/2),
vCoins, setCoinsRet, nValueRet, coin_selection_params)) {
return true;
}
// If partial groups are allowed, relax the requirement of spending OutputGroups (groups
// of UTXOs sent to the same address, which are obviously controlled by a single wallet)
// in their entirety.
- if (SelectCoinsMinConf(value_to_select, CoinEligibilityFilter(0, 1, max_ancestors-1, max_descendants-1, true /* include_partial_groups */),
+ if (AttemptSelection(value_to_select, CoinEligibilityFilter(0, 1, max_ancestors-1, max_descendants-1, true /* include_partial_groups */),
vCoins, setCoinsRet, nValueRet, coin_selection_params)) {
return true;
}
// Try with unsafe inputs if they are allowed. This may spend unconfirmed outputs
// received from other wallets.
if (coin_control.m_include_unsafe_inputs
- && SelectCoinsMinConf(value_to_select,
+ && AttemptSelection(value_to_select,
CoinEligibilityFilter(0 /* conf_mine */, 0 /* conf_theirs */, max_ancestors-1, max_descendants-1, true /* include_partial_groups */),
vCoins, setCoinsRet, nValueRet, coin_selection_params)) {
return true;
@@ -489,7 +489,7 @@ bool CWallet::SelectCoins(const std::vector<COutput>& vAvailableCoins, const CAm
// Try with unlimited ancestors/descendants. The transaction will still need to meet
// mempool ancestor/descendant policy to be accepted to mempool and broadcasted, but
// OutputGroups use heuristics that may overestimate ancestor/descendant counts.
- if (!fRejectLongChains && SelectCoinsMinConf(value_to_select,
+ if (!fRejectLongChains && AttemptSelection(value_to_select,
CoinEligibilityFilter(0, 1, std::numeric_limits<uint64_t>::max(), std::numeric_limits<uint64_t>::max(), true /* include_partial_groups */),
vCoins, setCoinsRet, nValueRet, coin_selection_params)) {
return true;
@@ -499,7 +499,7 @@ bool CWallet::SelectCoins(const std::vector<COutput>& vAvailableCoins, const CAm
return false;
}();
- // SelectCoinsMinConf clears setCoinsRet, so add the preset inputs from coin_control to the coinset
+ // AttemptSelection clears setCoinsRet, so add the preset inputs from coin_control to the coinset
util::insert(setCoinsRet, setPresetCoins);
// add preset inputs to the total value selected
@@ -578,287 +578,266 @@ bool CWallet::CreateTransactionInternal(
FeeCalculation& fee_calc_out,
bool sign)
{
- CAmount nValue = 0;
+ AssertLockHeld(cs_wallet);
+
+ CMutableTransaction txNew; // The resulting transaction that we make
+ txNew.nLockTime = GetLocktimeForNewTransaction(chain(), GetLastBlockHash(), GetLastBlockHeight());
+
+ CoinSelectionParams coin_selection_params; // Parameters for coin selection, init with dummy
+ coin_selection_params.m_avoid_partial_spends = coin_control.m_avoid_partial_spends;
+
+ CAmount recipients_sum = 0;
const OutputType change_type = TransactionChangeType(coin_control.m_change_type ? *coin_control.m_change_type : m_default_change_type, vecSend);
ReserveDestination reservedest(this, change_type);
- unsigned int nSubtractFeeFromAmount = 0;
- for (const auto& recipient : vecSend)
- {
- if (nValue < 0 || recipient.nAmount < 0)
- {
- error = _("Transaction amounts must not be negative");
- return false;
+ unsigned int outputs_to_subtract_fee_from = 0; // The number of outputs which we are subtracting the fee from
+ for (const auto& recipient : vecSend) {
+ recipients_sum += recipient.nAmount;
+
+ if (recipient.fSubtractFeeFromAmount) {
+ outputs_to_subtract_fee_from++;
+ coin_selection_params.m_subtract_fee_outputs = true;
}
- nValue += recipient.nAmount;
+ }
- if (recipient.fSubtractFeeFromAmount)
- nSubtractFeeFromAmount++;
+ // Create change script that will be used if we need change
+ // TODO: pass in scriptChange instead of reservedest so
+ // change transaction isn't always pay-to-bitcoin-address
+ CScript scriptChange;
+
+ // coin control: send change to custom address
+ if (!std::get_if<CNoDestination>(&coin_control.destChange)) {
+ scriptChange = GetScriptForDestination(coin_control.destChange);
+ } else { // no coin control: send change to newly generated address
+ // Note: We use a new key here to keep it from being obvious which side is the change.
+ // The drawback is that by not reusing a previous key, the change may be lost if a
+ // backup is restored, if the backup doesn't have the new private key for the change.
+ // If we reused the old key, it would be possible to add code to look for and
+ // rediscover unknown transactions that were written with keys of ours to recover
+ // post-backup change.
+
+ // Reserve a new key pair from key pool. If it fails, provide a dummy
+ // destination in case we don't need change.
+ CTxDestination dest;
+ if (!reservedest.GetReservedDestination(dest, true)) {
+ error = _("Transaction needs a change address, but we can't generate it. Please call keypoolrefill first.");
+ }
+ scriptChange = GetScriptForDestination(dest);
+ // A valid destination implies a change script (and
+ // vice-versa). An empty change script will abort later, if the
+ // change keypool ran out, but change is required.
+ CHECK_NONFATAL(IsValidDestination(dest) != scriptChange.empty());
}
- if (vecSend.empty())
- {
- error = _("Transaction must have at least one recipient");
- return false;
+ CTxOut change_prototype_txout(0, scriptChange);
+ coin_selection_params.change_output_size = GetSerializeSize(change_prototype_txout);
+
+ // Get size of spending the change output
+ int change_spend_size = CalculateMaximumSignedInputSize(change_prototype_txout, this);
+ // If the wallet doesn't know how to sign change output, assume p2sh-p2wpkh
+ // as lower-bound to allow BnB to do it's thing
+ if (change_spend_size == -1) {
+ coin_selection_params.change_spend_size = DUMMY_NESTED_P2WPKH_INPUT_SIZE;
+ } else {
+ coin_selection_params.change_spend_size = (size_t)change_spend_size;
}
- CMutableTransaction txNew;
+ // Set discard feerate
+ coin_selection_params.m_discard_feerate = GetDiscardRate(*this);
+
+ // Get the fee rate to use effective values in coin selection
FeeCalculation feeCalc;
- TxSize tx_sizes;
- int nBytes;
+ coin_selection_params.m_effective_feerate = GetMinimumFeeRate(*this, coin_control, &feeCalc);
+ // Do not, ever, assume that it's fine to change the fee rate if the user has explicitly
+ // provided one
+ if (coin_control.m_feerate && coin_selection_params.m_effective_feerate > *coin_control.m_feerate) {
+ error = strprintf(_("Fee rate (%s) is lower than the minimum fee rate setting (%s)"), coin_control.m_feerate->ToString(FeeEstimateMode::SAT_VB), coin_selection_params.m_effective_feerate.ToString(FeeEstimateMode::SAT_VB));
+ return false;
+ }
+ if (feeCalc.reason == FeeReason::FALLBACK && !m_allow_fallback_fee) {
+ // eventually allow a fallback fee
+ error = _("Fee estimation failed. Fallbackfee is disabled. Wait a few blocks or enable -fallbackfee.");
+ return false;
+ }
+
+ // Get long term estimate
+ CCoinControl cc_temp;
+ cc_temp.m_confirm_target = chain().estimateMaxBlocks();
+ coin_selection_params.m_long_term_feerate = GetMinimumFeeRate(*this, cc_temp, nullptr);
+
+ // Calculate the cost of change
+ // Cost of change is the cost of creating the change output + cost of spending the change output in the future.
+ // For creating the change output now, we use the effective feerate.
+ // For spending the change output in the future, we use the discard feerate for now.
+ // So cost of change = (change output size * effective feerate) + (size of spending change output * discard feerate)
+ coin_selection_params.m_change_fee = coin_selection_params.m_effective_feerate.GetFee(coin_selection_params.change_output_size);
+ coin_selection_params.m_cost_of_change = coin_selection_params.m_discard_feerate.GetFee(coin_selection_params.change_spend_size) + coin_selection_params.m_change_fee;
+
+ // vouts to the payees
+ if (!coin_selection_params.m_subtract_fee_outputs) {
+ coin_selection_params.tx_noinputs_size = 11; // Static vsize overhead + outputs vsize. 4 nVersion, 4 nLocktime, 1 input count, 1 output count, 1 witness overhead (dummy, flag, stack size)
+ }
+ for (const auto& recipient : vecSend)
{
- std::set<CInputCoin> setCoins;
- LOCK(cs_wallet);
- txNew.nLockTime = GetLocktimeForNewTransaction(chain(), GetLastBlockHash(), GetLastBlockHeight());
- {
- std::vector<COutput> vAvailableCoins;
- AvailableCoins(vAvailableCoins, &coin_control, 1, MAX_MONEY, MAX_MONEY, 0);
- CoinSelectionParams coin_selection_params; // Parameters for coin selection, init with dummy
- coin_selection_params.m_avoid_partial_spends = coin_control.m_avoid_partial_spends;
-
- // Create change script that will be used if we need change
- // TODO: pass in scriptChange instead of reservedest so
- // change transaction isn't always pay-to-bitcoin-address
- CScript scriptChange;
-
- // coin control: send change to custom address
- if (!std::get_if<CNoDestination>(&coin_control.destChange)) {
- scriptChange = GetScriptForDestination(coin_control.destChange);
- } else { // no coin control: send change to newly generated address
- // Note: We use a new key here to keep it from being obvious which side is the change.
- // The drawback is that by not reusing a previous key, the change may be lost if a
- // backup is restored, if the backup doesn't have the new private key for the change.
- // If we reused the old key, it would be possible to add code to look for and
- // rediscover unknown transactions that were written with keys of ours to recover
- // post-backup change.
-
- // Reserve a new key pair from key pool. If it fails, provide a dummy
- // destination in case we don't need change.
- CTxDestination dest;
- if (!reservedest.GetReservedDestination(dest, true)) {
- error = _("Transaction needs a change address, but we can't generate it. Please call keypoolrefill first.");
- }
- scriptChange = GetScriptForDestination(dest);
- // A valid destination implies a change script (and
- // vice-versa). An empty change script will abort later, if the
- // change keypool ran out, but change is required.
- CHECK_NONFATAL(IsValidDestination(dest) != scriptChange.empty());
- }
- CTxOut change_prototype_txout(0, scriptChange);
- coin_selection_params.change_output_size = GetSerializeSize(change_prototype_txout);
-
- // Get size of spending the change output
- int change_spend_size = CalculateMaximumSignedInputSize(change_prototype_txout, this);
- // If the wallet doesn't know how to sign change output, assume p2sh-p2wpkh
- // as lower-bound to allow BnB to do it's thing
- if (change_spend_size == -1) {
- coin_selection_params.change_spend_size = DUMMY_NESTED_P2WPKH_INPUT_SIZE;
- } else {
- coin_selection_params.change_spend_size = (size_t)change_spend_size;
- }
+ CTxOut txout(recipient.nAmount, recipient.scriptPubKey);
- // Set discard feerate
- coin_selection_params.m_discard_feerate = GetDiscardRate(*this);
+ // Include the fee cost for outputs.
+ if (!coin_selection_params.m_subtract_fee_outputs) {
+ coin_selection_params.tx_noinputs_size += ::GetSerializeSize(txout, PROTOCOL_VERSION);
+ }
- // Get the fee rate to use effective values in coin selection
- coin_selection_params.m_effective_feerate = GetMinimumFeeRate(*this, coin_control, &feeCalc);
- // Do not, ever, assume that it's fine to change the fee rate if the user has explicitly
- // provided one
- if (coin_control.m_feerate && coin_selection_params.m_effective_feerate > *coin_control.m_feerate) {
- error = strprintf(_("Fee rate (%s) is lower than the minimum fee rate setting (%s)"), coin_control.m_feerate->ToString(FeeEstimateMode::SAT_VB), coin_selection_params.m_effective_feerate.ToString(FeeEstimateMode::SAT_VB));
- return false;
- }
- if (feeCalc.reason == FeeReason::FALLBACK && !m_allow_fallback_fee) {
- // eventually allow a fallback fee
- error = _("Fee estimation failed. Fallbackfee is disabled. Wait a few blocks or enable -fallbackfee.");
- return false;
- }
+ if (IsDust(txout, chain().relayDustFee()))
+ {
+ error = _("Transaction amount too small");
+ return false;
+ }
+ txNew.vout.push_back(txout);
+ }
- // Get long term estimate
- CCoinControl cc_temp;
- cc_temp.m_confirm_target = chain().estimateMaxBlocks();
- coin_selection_params.m_long_term_feerate = GetMinimumFeeRate(*this, cc_temp, nullptr);
+ // Include the fees for things that aren't inputs, excluding the change output
+ const CAmount not_input_fees = coin_selection_params.m_effective_feerate.GetFee(coin_selection_params.tx_noinputs_size);
+ CAmount selection_target = recipients_sum + not_input_fees;
- // Calculate the cost of change
- // Cost of change is the cost of creating the change output + cost of spending the change output in the future.
- // For creating the change output now, we use the effective feerate.
- // For spending the change output in the future, we use the discard feerate for now.
- // So cost of change = (change output size * effective feerate) + (size of spending change output * discard feerate)
- coin_selection_params.m_change_fee = coin_selection_params.m_effective_feerate.GetFee(coin_selection_params.change_output_size);
- coin_selection_params.m_cost_of_change = coin_selection_params.m_discard_feerate.GetFee(coin_selection_params.change_spend_size) + coin_selection_params.m_change_fee;
+ // Get available coins
+ std::vector<COutput> vAvailableCoins;
+ AvailableCoins(vAvailableCoins, &coin_control, 1, MAX_MONEY, MAX_MONEY, 0);
- coin_selection_params.m_subtract_fee_outputs = nSubtractFeeFromAmount != 0; // If we are doing subtract fee from recipient, don't use effective values
+ // Choose coins to use
+ CAmount inputs_sum = 0;
+ std::set<CInputCoin> setCoins;
+ if (!SelectCoins(vAvailableCoins, /* nTargetValue */ selection_target, setCoins, inputs_sum, coin_control, coin_selection_params))
+ {
+ error = _("Insufficient funds");
+ return false;
+ }
- // vouts to the payees
- if (!coin_selection_params.m_subtract_fee_outputs) {
- coin_selection_params.tx_noinputs_size = 11; // Static vsize overhead + outputs vsize. 4 nVersion, 4 nLocktime, 1 input count, 1 output count, 1 witness overhead (dummy, flag, stack size)
- }
- for (const auto& recipient : vecSend)
- {
- CTxOut txout(recipient.nAmount, recipient.scriptPubKey);
+ // Always make a change output
+ // We will reduce the fee from this change output later, and remove the output if it is too small.
+ const CAmount change_and_fee = inputs_sum - recipients_sum;
+ assert(change_and_fee >= 0);
+ CTxOut newTxOut(change_and_fee, scriptChange);
- // Include the fee cost for outputs.
- if (!coin_selection_params.m_subtract_fee_outputs) {
- coin_selection_params.tx_noinputs_size += ::GetSerializeSize(txout, PROTOCOL_VERSION);
- }
+ if (nChangePosInOut == -1)
+ {
+ // Insert change txn at random position:
+ nChangePosInOut = GetRandInt(txNew.vout.size()+1);
+ }
+ else if ((unsigned int)nChangePosInOut > txNew.vout.size())
+ {
+ error = _("Change index out of range");
+ return false;
+ }
- if (IsDust(txout, chain().relayDustFee()))
- {
- error = _("Transaction amount too small");
- return false;
- }
- txNew.vout.push_back(txout);
- }
+ assert(nChangePosInOut != -1);
+ auto change_position = txNew.vout.insert(txNew.vout.begin() + nChangePosInOut, newTxOut);
- // Include the fees for things that aren't inputs, excluding the change output
- const CAmount not_input_fees = coin_selection_params.m_effective_feerate.GetFee(coin_selection_params.tx_noinputs_size);
- CAmount nValueToSelect = nValue + not_input_fees;
+ // Shuffle selected coins and fill in final vin
+ std::vector<CInputCoin> selected_coins(setCoins.begin(), setCoins.end());
+ Shuffle(selected_coins.begin(), selected_coins.end(), FastRandomContext());
- // Choose coins to use
- CAmount inputs_sum = 0;
- setCoins.clear();
- if (!SelectCoins(vAvailableCoins, /* nTargetValue */ nValueToSelect, setCoins, inputs_sum, coin_control, coin_selection_params))
- {
- error = _("Insufficient funds");
- return false;
- }
-
- // Always make a change output
- // We will reduce the fee from this change output later, and remove the output if it is too small.
- const CAmount change_and_fee = inputs_sum - nValue;
- assert(change_and_fee >= 0);
- CTxOut newTxOut(change_and_fee, scriptChange);
+ // Note how the sequence number is set to non-maxint so that
+ // the nLockTime set above actually works.
+ //
+ // BIP125 defines opt-in RBF as any nSequence < maxint-1, so
+ // we use the highest possible value in that range (maxint-2)
+ // to avoid conflicting with other possible uses of nSequence,
+ // and in the spirit of "smallest possible change from prior
+ // behavior."
+ const uint32_t nSequence = coin_control.m_signal_bip125_rbf.value_or(m_signal_rbf) ? MAX_BIP125_RBF_SEQUENCE : (CTxIn::SEQUENCE_FINAL - 1);
+ for (const auto& coin : selected_coins) {
+ txNew.vin.push_back(CTxIn(coin.outpoint, CScript(), nSequence));
+ }
- if (nChangePosInOut == -1)
- {
- // Insert change txn at random position:
- nChangePosInOut = GetRandInt(txNew.vout.size()+1);
- }
- else if ((unsigned int)nChangePosInOut > txNew.vout.size())
- {
- error = _("Change index out of range");
- return false;
- }
+ // Calculate the transaction fee
+ TxSize tx_sizes = CalculateMaximumSignedTxSize(CTransaction(txNew), this, coin_control.fAllowWatchOnly);
+ int nBytes = tx_sizes.vsize;
+ if (nBytes < 0) {
+ error = _("Signing transaction failed");
+ return false;
+ }
+ nFeeRet = coin_selection_params.m_effective_feerate.GetFee(nBytes);
- assert(nChangePosInOut != -1);
- auto change_position = txNew.vout.insert(txNew.vout.begin() + nChangePosInOut, newTxOut);
+ // Subtract fee from the change output if not subtracting it from recipient outputs
+ CAmount fee_needed = nFeeRet;
+ if (!coin_selection_params.m_subtract_fee_outputs) {
+ change_position->nValue -= fee_needed;
+ }
- // Dummy fill vin for maximum size estimation
- //
- for (const auto& coin : setCoins) {
- txNew.vin.push_back(CTxIn(coin.outpoint,CScript()));
- }
+ // We want to drop the change to fees if:
+ // 1. The change output would be dust
+ // 2. The change is within the (almost) exact match window, i.e. it is less than or equal to the cost of the change output (cost_of_change)
+ CAmount change_amount = change_position->nValue;
+ if (IsDust(*change_position, coin_selection_params.m_discard_feerate) || change_amount <= coin_selection_params.m_cost_of_change)
+ {
+ nChangePosInOut = -1;
+ change_amount = 0;
+ txNew.vout.erase(change_position);
+
+ // Because we have dropped this change, the tx size and required fee will be different, so let's recalculate those
+ tx_sizes = CalculateMaximumSignedTxSize(CTransaction(txNew), this, coin_control.fAllowWatchOnly);
+ nBytes = tx_sizes.vsize;
+ fee_needed = coin_selection_params.m_effective_feerate.GetFee(nBytes);
+ }
- // Calculate the transaction fee
- tx_sizes = CalculateMaximumSignedTxSize(CTransaction(txNew), this, coin_control.fAllowWatchOnly);
- nBytes = tx_sizes.vsize;
- if (nBytes < 0) {
- error = _("Signing transaction failed");
- return false;
- }
- nFeeRet = coin_selection_params.m_effective_feerate.GetFee(nBytes);
+ // Update nFeeRet in case fee_needed changed due to dropping the change output
+ if (fee_needed <= change_and_fee - change_amount) {
+ nFeeRet = change_and_fee - change_amount;
+ }
- // Subtract fee from the change output if not subtrating it from recipient outputs
- CAmount fee_needed = nFeeRet;
- if (nSubtractFeeFromAmount == 0) {
- change_position->nValue -= fee_needed;
+ // Reduce output values for subtractFeeFromAmount
+ if (coin_selection_params.m_subtract_fee_outputs) {
+ CAmount to_reduce = fee_needed + change_amount - change_and_fee;
+ int i = 0;
+ bool fFirst = true;
+ for (const auto& recipient : vecSend)
+ {
+ if (i == nChangePosInOut) {
+ ++i;
}
+ CTxOut& txout = txNew.vout[i];
- // We want to drop the change to fees if:
- // 1. The change output would be dust
- // 2. The change is within the (almost) exact match window, i.e. it is less than or equal to the cost of the change output (cost_of_change)
- CAmount change_amount = change_position->nValue;
- if (IsDust(*change_position, coin_selection_params.m_discard_feerate) || change_amount <= coin_selection_params.m_cost_of_change)
+ if (recipient.fSubtractFeeFromAmount)
{
- nChangePosInOut = -1;
- change_amount = 0;
- txNew.vout.erase(change_position);
-
- // Because we have dropped this change, the tx size and required fee will be different, so let's recalculate those
- tx_sizes = CalculateMaximumSignedTxSize(CTransaction(txNew), this, coin_control.fAllowWatchOnly);
- nBytes = tx_sizes.vsize;
- fee_needed = coin_selection_params.m_effective_feerate.GetFee(nBytes);
- }
+ txout.nValue -= to_reduce / outputs_to_subtract_fee_from; // Subtract fee equally from each selected recipient
- // Update nFeeRet in case fee_needed changed due to dropping the change output
- if (fee_needed <= change_and_fee - change_amount) {
- nFeeRet = change_and_fee - change_amount;
- }
-
- // Reduce output values for subtractFeeFromAmount
- if (nSubtractFeeFromAmount != 0) {
- CAmount to_reduce = fee_needed + change_amount - change_and_fee;
- int i = 0;
- bool fFirst = true;
- for (const auto& recipient : vecSend)
+ if (fFirst) // first receiver pays the remainder not divisible by output count
{
- if (i == nChangePosInOut) {
- ++i;
- }
- CTxOut& txout = txNew.vout[i];
-
- if (recipient.fSubtractFeeFromAmount)
- {
- txout.nValue -= to_reduce / nSubtractFeeFromAmount; // Subtract fee equally from each selected recipient
-
- if (fFirst) // first receiver pays the remainder not divisible by output count
- {
- fFirst = false;
- txout.nValue -= to_reduce % nSubtractFeeFromAmount;
- }
-
- // Error if this output is reduced to be below dust
- if (IsDust(txout, chain().relayDustFee())) {
- if (txout.nValue < 0) {
- error = _("The transaction amount is too small to pay the fee");
- } else {
- error = _("The transaction amount is too small to send after the fee has been deducted");
- }
- return false;
- }
- }
- ++i;
+ fFirst = false;
+ txout.nValue -= to_reduce % outputs_to_subtract_fee_from;
}
- nFeeRet = fee_needed;
- }
- // Give up if change keypool ran out and change is required
- if (scriptChange.empty() && nChangePosInOut != -1) {
- return false;
+ // Error if this output is reduced to be below dust
+ if (IsDust(txout, chain().relayDustFee())) {
+ if (txout.nValue < 0) {
+ error = _("The transaction amount is too small to pay the fee");
+ } else {
+ error = _("The transaction amount is too small to send after the fee has been deducted");
+ }
+ return false;
+ }
}
+ ++i;
}
+ nFeeRet = fee_needed;
+ }
- // Shuffle selected coins and fill in final vin
- txNew.vin.clear();
- std::vector<CInputCoin> selected_coins(setCoins.begin(), setCoins.end());
- Shuffle(selected_coins.begin(), selected_coins.end(), FastRandomContext());
-
- // Note how the sequence number is set to non-maxint so that
- // the nLockTime set above actually works.
- //
- // BIP125 defines opt-in RBF as any nSequence < maxint-1, so
- // we use the highest possible value in that range (maxint-2)
- // to avoid conflicting with other possible uses of nSequence,
- // and in the spirit of "smallest possible change from prior
- // behavior."
- const uint32_t nSequence = coin_control.m_signal_bip125_rbf.value_or(m_signal_rbf) ? MAX_BIP125_RBF_SEQUENCE : (CTxIn::SEQUENCE_FINAL - 1);
- for (const auto& coin : selected_coins) {
- txNew.vin.push_back(CTxIn(coin.outpoint, CScript(), nSequence));
- }
+ // Give up if change keypool ran out and change is required
+ if (scriptChange.empty() && nChangePosInOut != -1) {
+ return false;
+ }
- if (sign && !SignTransaction(txNew)) {
- error = _("Signing transaction failed");
- return false;
- }
+ if (sign && !SignTransaction(txNew)) {
+ error = _("Signing transaction failed");
+ return false;
+ }
- // Return the constructed transaction data.
- tx = MakeTransactionRef(std::move(txNew));
+ // Return the constructed transaction data.
+ tx = MakeTransactionRef(std::move(txNew));
- // Limit size
- if ((sign && GetTransactionWeight(*tx) > MAX_STANDARD_TX_WEIGHT) ||
- (!sign && tx_sizes.weight > MAX_STANDARD_TX_WEIGHT))
- {
- error = _("Transaction too large");
- return false;
- }
+ // Limit size
+ if ((sign && GetTransactionWeight(*tx) > MAX_STANDARD_TX_WEIGHT) ||
+ (!sign && tx_sizes.weight > MAX_STANDARD_TX_WEIGHT))
+ {
+ error = _("Transaction too large");
+ return false;
}
if (nFeeRet > m_default_max_tx_fee) {
@@ -900,6 +879,18 @@ bool CWallet::CreateTransaction(
FeeCalculation& fee_calc_out,
bool sign)
{
+ if (vecSend.empty()) {
+ error = _("Transaction must have at least one recipient");
+ return false;
+ }
+
+ if (std::any_of(vecSend.cbegin(), vecSend.cend(), [](const auto& recipient){ return recipient.nAmount < 0; })) {
+ error = _("Transaction amounts must not be negative");
+ return false;
+ }
+
+ LOCK(cs_wallet);
+
int nChangePosIn = nChangePosInOut;
Assert(!tx); // tx is an out-param. TODO change the return type from bool to tx (or nullptr)
bool res = CreateTransactionInternal(vecSend, tx, nFeeRet, nChangePosInOut, error, coin_control, fee_calc_out, sign);