diff options
| -rw-r--r-- | src/wallet/spend.cpp | 369 | ||||
| -rw-r--r-- | src/wallet/wallet.h | 2 |
2 files changed, 186 insertions, 185 deletions
diff --git a/src/wallet/spend.cpp b/src/wallet/spend.cpp index 97fc7acca5..00edc94403 100644 --- a/src/wallet/spend.cpp +++ b/src/wallet/spend.cpp @@ -578,6 +578,8 @@ bool CWallet::CreateTransactionInternal( FeeCalculation& fee_calc_out, bool sign) { + AssertLockHeld(cs_wallet); + CAmount nValue = 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); @@ -606,224 +608,221 @@ bool CWallet::CreateTransactionInternal( int nBytes; { 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; - } + 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; + } - // Set discard feerate - coin_selection_params.m_discard_feerate = GetDiscardRate(*this); + // Set discard feerate + coin_selection_params.m_discard_feerate = GetDiscardRate(*this); - // 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; - } + // 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; + } - // 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); + // 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; + // 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; - coin_selection_params.m_subtract_fee_outputs = nSubtractFeeFromAmount != 0; // If we are doing subtract fee from recipient, don't use effective values + coin_selection_params.m_subtract_fee_outputs = nSubtractFeeFromAmount != 0; // If we are doing subtract fee from recipient, don't use effective values - // vouts to the payees + // 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); + + // Include the fee cost for outputs. 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) + coin_selection_params.tx_noinputs_size += ::GetSerializeSize(txout, PROTOCOL_VERSION); } - for (const auto& recipient : vecSend) + + if (IsDust(txout, chain().relayDustFee())) { - CTxOut txout(recipient.nAmount, recipient.scriptPubKey); + error = _("Transaction amount too small"); + return false; + } + txNew.vout.push_back(txout); + } - // Include the fee cost for outputs. - if (!coin_selection_params.m_subtract_fee_outputs) { - coin_selection_params.tx_noinputs_size += ::GetSerializeSize(txout, PROTOCOL_VERSION); - } + // 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; - if (IsDust(txout, chain().relayDustFee())) - { - error = _("Transaction amount too small"); - return false; - } - txNew.vout.push_back(txout); - } + // 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; + } - // 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; + // 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); - // 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; - } + 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; + } - // 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); + assert(nChangePosInOut != -1); + auto change_position = txNew.vout.insert(txNew.vout.begin() + nChangePosInOut, newTxOut); - 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; - } + // Dummy fill vin for maximum size estimation + // + for (const auto& coin : setCoins) { + txNew.vin.push_back(CTxIn(coin.outpoint,CScript())); + } - assert(nChangePosInOut != -1); - auto change_position = txNew.vout.insert(txNew.vout.begin() + nChangePosInOut, newTxOut); + // 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); - // Dummy fill vin for maximum size estimation - // - for (const auto& coin : setCoins) { - txNew.vin.push_back(CTxIn(coin.outpoint,CScript())); - } + // 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; + } - // Calculate the transaction fee + // 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; - if (nBytes < 0) { - error = _("Signing transaction failed"); - return false; - } - nFeeRet = coin_selection_params.m_effective_feerate.GetFee(nBytes); + fee_needed = coin_selection_params.m_effective_feerate.GetFee(nBytes); + } - // 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; - } + // 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; + } - // 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) + // 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) { - 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); - } - - // 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; - } + if (i == nChangePosInOut) { + ++i; + } + CTxOut& txout = txNew.vout[i]; - // 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 (recipient.fSubtractFeeFromAmount) { - if (i == nChangePosInOut) { - ++i; - } - CTxOut& txout = txNew.vout[i]; + txout.nValue -= to_reduce / nSubtractFeeFromAmount; // Subtract fee equally from each selected recipient - if (recipient.fSubtractFeeFromAmount) + if (fFirst) // first receiver pays the remainder not divisible by output count { - 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; - } + 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; + // 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; + ++i; } + nFeeRet = fee_needed; + } - // Give up if change keypool ran out and change is required - if (scriptChange.empty() && nChangePosInOut != -1) { - return false; - } + // Give up if change keypool ran out and change is required + if (scriptChange.empty() && nChangePosInOut != -1) { + return false; } // Shuffle selected coins and fill in final vin @@ -900,6 +899,8 @@ bool CWallet::CreateTransaction( FeeCalculation& fee_calc_out, bool sign) { + 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); diff --git a/src/wallet/wallet.h b/src/wallet/wallet.h index 4a3e0f7054..a58b418b6d 100644 --- a/src/wallet/wallet.h +++ b/src/wallet/wallet.h @@ -326,7 +326,7 @@ private: // ScriptPubKeyMan::GetID. In many cases it will be the hash of an internal structure std::map<uint256, std::unique_ptr<ScriptPubKeyMan>> m_spk_managers; - bool CreateTransactionInternal(const std::vector<CRecipient>& vecSend, CTransactionRef& tx, CAmount& nFeeRet, int& nChangePosInOut, bilingual_str& error, const CCoinControl& coin_control, FeeCalculation& fee_calc_out, bool sign); + bool CreateTransactionInternal(const std::vector<CRecipient>& vecSend, CTransactionRef& tx, CAmount& nFeeRet, int& nChangePosInOut, bilingual_str& error, const CCoinControl& coin_control, FeeCalculation& fee_calc_out, bool sign) EXCLUSIVE_LOCKS_REQUIRED(cs_wallet); /** * Catch wallet up to current chain, scanning new blocks, updating the best |