src/qt/multisigdialog.cpp

   1 #include <QClipboard>
   2 #include <QDialog>
   3 #include <QMessageBox>
   4 #include <QScrollBar>
   5 #include <vector>
   6
   7 #include "addresstablemodel.h"
   8 #include "base58.h"
   9 #include "key.h"
  10 #include "main.h"
  11 #include "multisigaddressentry.h"
  12 #include "multisiginputentry.h"
  13 #include "multisigdialog.h"
  14 #include "ui_multisigdialog.h"
  15 #include "script.h"
  16 #include "sendcoinsentry.h"
  17 #include "util.h"
  18 #include "wallet.h"
  19 #include "walletmodel.h"
  20
  21 #ifdef USE_LEVELDB
  22 #include "txdb-leveldb.h"
  23 #else
  24 #include "txdb-bdb.h"
  25 #endif
  26
  27 #ifdef _MSC_VER
  28 #pragma warning( disable : 4101)
  29 #endif
  30
  31 MultisigDialog::MultisigDialog(QWidget *parent) : QDialog(parent), ui(new Ui::MultisigDialog), model(0)
  32 {
  33     ui->setupUi(this);
  34
  35 #ifdef Q_WS_MAC // Icons on push buttons are very uncommon on Mac
  36     ui->addPubKeyButton->setIcon(QIcon());
  37     ui->clearButton->setIcon(QIcon());
  38     ui->addInputButton->setIcon(QIcon());
  39     ui->addOutputButton->setIcon(QIcon());
  40     ui->signTransactionButton->setIcon(QIcon());
  41     ui->sendTransactionButton->setIcon(QIcon());
  42 #endif
  43
  44     addPubKey();
  45     addPubKey();
  46
  47     connect(ui->addPubKeyButton, SIGNAL(clicked()), this, SLOT(addPubKey()));
  48     connect(ui->clearButton, SIGNAL(clicked()), this, SLOT(clear()));
  49
  50     addInput();
  51     addOutput();
  52
  53     connect(ui->addInputButton, SIGNAL(clicked()), this, SLOT(addInput()));
  54     connect(ui->addOutputButton, SIGNAL(clicked()), this, SLOT(addOutput()));
  55
  56     ui->signTransactionButton->setEnabled(false);
  57     ui->sendTransactionButton->setEnabled(false);
  58 }
  59
  60 void MultisigDialog::showEvent(QShowEvent *event)
  61 {
  62     QWidget::showEvent(event);
  63
  64     if (!model)
  65         return;
  66
  67     updateAmounts();
  68 }
  69
  70 void MultisigDialog::hideEvent(QHideEvent *event)
  71 {
  72     QWidget::hideEvent(event);
  73
  74     if (!model)
  75         return;
  76
  77     clear();
  78 }
  79
  80 MultisigDialog::~MultisigDialog()
  81 {
  82     delete ui;
  83 }
  84
  85 void MultisigDialog::setModel(WalletModel *model)
  86 {
  87     this->model = model;
  88
  89     for(int i = 0; i < ui->pubkeyEntries->count(); i++)
  90     {
  91         MultisigAddressEntry *entry = qobject_cast<MultisigAddressEntry *>(ui->pubkeyEntries->itemAt(i)->widget());
  92         if(entry)
  93             entry->setModel(model);
  94     }
  95
  96
  97     for(int i = 0; i < ui->inputs->count(); i++)
  98     {
  99         MultisigInputEntry *entry = qobject_cast<MultisigInputEntry *>(ui->inputs->itemAt(i)->widget());
 100         if(entry)
 101             entry->setModel(model);
 102     }
 103
 104
 105     for(int i = 0; i < ui->outputs->count(); i++)
 106     {
 107         SendCoinsEntry *entry = qobject_cast<SendCoinsEntry *>(ui->outputs->itemAt(i)->widget());
 108         if(entry)
 109             entry->setModel(model);
 110     }
 111 }
 112
 113 void MultisigDialog::updateRemoveEnabled()
 114 {
 115     bool enabled = (ui->pubkeyEntries->count() > 2);
 116
 117     for(int i = 0; i < ui->pubkeyEntries->count(); i++)
 118     {
 119         MultisigAddressEntry *entry = qobject_cast<MultisigAddressEntry *>(ui->pubkeyEntries->itemAt(i)->widget());
 120         if(entry)
 121             entry->setRemoveEnabled(enabled);
 122     }
 123
 124     QString maxSigsStr;
 125     maxSigsStr.setNum(ui->pubkeyEntries->count());
 126     ui->maxSignaturesLabel->setText(QString("/ ") + maxSigsStr);
 127
 128
 129     enabled = (ui->inputs->count() > 1);
 130     for(int i = 0; i < ui->inputs->count(); i++)
 131     {
 132         MultisigInputEntry *entry = qobject_cast<MultisigInputEntry *>(ui->inputs->itemAt(i)->widget());
 133         if(entry)
 134             entry->setRemoveEnabled(enabled);
 135     }
 136
 137
 138     enabled = (ui->outputs->count() > 1);
 139     for(int i = 0; i < ui->outputs->count(); i++)
 140     {
 141         SendCoinsEntry *entry = qobject_cast<SendCoinsEntry *>(ui->outputs->itemAt(i)->widget());
 142         if(entry)
 143             entry->setRemoveEnabled(enabled);
 144     }
 145 }
 146
 147 void MultisigDialog::on_createAddressButton_clicked()
 148 {
 149     ui->multisigAddress->clear();
 150     ui->redeemScript->clear();
 151
 152     if(!model)
 153         return;
 154
 155     std::vector<CKey> pubkeys;
 156     pubkeys.resize(ui->pubkeyEntries->count());
 157     unsigned int required = ui->requiredSignatures->text().toUInt();
 158
 159     for(int i = 0; i < ui->pubkeyEntries->count(); i++)
 160     {
 161         MultisigAddressEntry *entry = qobject_cast<MultisigAddressEntry *>(ui->pubkeyEntries->itemAt(i)->widget());
 162         if(!entry->validate())
 163             return;
 164         QString str = entry->getPubkey();
 165         CPubKey vchPubKey(ParseHex(str.toStdString().c_str()));
 166         if(!vchPubKey.IsValid())
 167             return;
 168         pubkeys[i].SetPubKey(vchPubKey);
 169     }
 170
 171     if(pubkeys.size() > 16)
 172     {
 173         QMessageBox::warning(this, tr("Error"), tr("Number of addresses involved in the address creation > %1\nReduce the number").arg(16), QMessageBox::Ok);
 174         return;
 175     }
 176
 177     if(required == 0)
 178     {
 179         QMessageBox::warning(this, tr("Error"), tr("Number of required signatures is 0\nNumber of required signatures must be between 1 and number of keys involved in the creation of address."), QMessageBox::Ok);
 180         return;
 181     }
 182
 183     if(required > pubkeys.size())
 184     {
 185         QMessageBox::warning(this, tr("Error"), tr("Number of required signatures > Number of keys involved in the creation of address."), QMessageBox::Ok);
 186         return;
 187     }
 188
 189     CScript script;
 190     script.SetMultisig(required, pubkeys);
 191     if (script.size() > MAX_SCRIPT_ELEMENT_SIZE)
 192     {
 193         QMessageBox::warning(this, tr("Error"), tr("Redeem script exceeds size limit: %1 > %2\nReduce the number of addresses involved in the address creation.").arg(script.size()).arg(MAX_SCRIPT_ELEMENT_SIZE), QMessageBox::Ok);
 194         return;
 195     }
 196     CScriptID scriptID = script.GetID();
 197     CBitcoinAddress address(scriptID);
 198
 199     ui->multisigAddress->setText(address.ToString().c_str());
 200     ui->redeemScript->setText(HexStr(script.begin(), script.end()).c_str());
 201 }
 202
 203 void MultisigDialog::on_copyMultisigAddressButton_clicked()
 204 {
 205     QApplication::clipboard()->setText(ui->multisigAddress->text());
 206 }
 207
 208 void MultisigDialog::on_copyRedeemScriptButton_clicked()
 209 {
 210     QApplication::clipboard()->setText(ui->redeemScript->text());
 211 }
 212
 213 void MultisigDialog::on_saveRedeemScriptButton_clicked()
 214 {
 215     if(!model)
 216         return;
 217
 218     CWallet *wallet = model->getWallet();
 219     std::string redeemScript = ui->redeemScript->text().toStdString();
 220     std::vector<unsigned char> scriptData(ParseHex(redeemScript));
 221     CScript script(scriptData.begin(), scriptData.end());
 222     CScriptID scriptID = script.GetID();
 223
 224     LOCK(wallet->cs_wallet);
 225     if(!wallet->HaveCScript(scriptID))
 226         wallet->AddCScript(script);
 227 }
 228
 229 void MultisigDialog::on_saveMultisigAddressButton_clicked()
 230 {
 231     if(!model)
 232         return;
 233
 234     CWallet *wallet = model->getWallet();
 235     std::string redeemScript = ui->redeemScript->text().toStdString();
 236     std::string address = ui->multisigAddress->text().toStdString();
 237     std::string label("multisig");
 238
 239     if(!model->validateAddress(QString(address.c_str())))
 240         return;
 241
 242     std::vector<unsigned char> scriptData(ParseHex(redeemScript));
 243     CScript script(scriptData.begin(), scriptData.end());
 244     CScriptID scriptID = script.GetID();
 245
 246     LOCK(wallet->cs_wallet);
 247     if(!wallet->HaveCScript(scriptID))
 248         wallet->AddCScript(script);
 249     if(!wallet->mapAddressBook.count(CBitcoinAddress(address).Get()))
 250         wallet->SetAddressBookName(CBitcoinAddress(address).Get(), label);
 251 }
 252
 253 void MultisigDialog::clear()
 254 {
 255     while(ui->pubkeyEntries->count())
 256         delete ui->pubkeyEntries->takeAt(0)->widget();
 257
 258     addPubKey();
 259     addPubKey();
 260     updateRemoveEnabled();
 261 }
 262
 263 MultisigAddressEntry * MultisigDialog::addPubKey()
 264 {
 265     MultisigAddressEntry *entry = new MultisigAddressEntry(this);
 266
 267     entry->setModel(model);
 268     ui->pubkeyEntries->addWidget(entry);
 269     connect(entry, SIGNAL(removeEntry(MultisigAddressEntry *)), this, SLOT(removeEntry(MultisigAddressEntry *)));
 270     updateRemoveEnabled();
 271     entry->clear();
 272     ui->scrollAreaWidgetContents->resize(ui->scrollAreaWidgetContents->sizeHint());
 273     QScrollBar *bar = ui->scrollArea->verticalScrollBar();
 274     if(bar)
 275         bar->setSliderPosition(bar->maximum());
 276
 277     return entry;
 278 }
 279
 280 void MultisigDialog::removeEntry(MultisigAddressEntry *entry)
 281 {
 282     delete entry;
 283     updateRemoveEnabled();
 284 }
 285
 286 void MultisigDialog::on_createTransactionButton_clicked()
 287 {
 288     CTransaction transaction;
 289
 290     // Get inputs
 291     for(int i = 0; i < ui->inputs->count(); i++)
 292     {
 293         MultisigInputEntry *entry = qobject_cast<MultisigInputEntry *>(ui->inputs->itemAt(i)->widget());
 294         if(entry)
 295         {
 296             if(entry->validate())
 297             {
 298                 CTxIn input = entry->getInput();
 299                 transaction.vin.push_back(input);
 300             }
 301             else
 302                 return;
 303         }
 304     }
 305
 306     // Get outputs
 307     for(int i = 0; i < ui->outputs->count(); i++)
 308     {
 309         SendCoinsEntry *entry = qobject_cast<SendCoinsEntry *>(ui->outputs->itemAt(i)->widget());
 310
 311         if(entry)
 312         {
 313             if(entry->validate())
 314             {
 315                 SendCoinsRecipient recipient = entry->getValue();
 316                 CBitcoinAddress address(recipient.address.toStdString());
 317                 CScript scriptPubKey;
 318                 scriptPubKey.SetDestination(address.Get());
 319                 int64_t amount = recipient.amount;
 320                 CTxOut output(amount, scriptPubKey);
 321                 transaction.vout.push_back(output);
 322             }
 323             else
 324                 return;
 325         }
 326     }
 327
 328     CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
 329     ss << transaction;
 330     ui->transaction->setText(HexStr(ss.begin(), ss.end()).c_str());
 331 }
 332
 333 void MultisigDialog::on_transaction_textChanged()
 334 {
 335     while(ui->inputs->count())
 336         delete ui->inputs->takeAt(0)->widget();
 337     while(ui->outputs->count())
 338         delete ui->outputs->takeAt(0)->widget();
 339
 340     if(ui->transaction->text().size() > 0)
 341         ui->signTransactionButton->setEnabled(true);
 342     else
 343         ui->signTransactionButton->setEnabled(false);
 344
 345     // Decode the raw transaction
 346     std::vector<unsigned char> txData(ParseHex(ui->transaction->text().toStdString()));
 347     CDataStream ss(txData, SER_NETWORK, PROTOCOL_VERSION);
 348     CTransaction tx;
 349     try
 350     {
 351         ss >> tx;
 352     }
 353     catch(std::exception &e)
 354     {
 355         return;
 356     }
 357
 358     // Fill input list
 359     int index = -1;
 360     BOOST_FOREACH(const CTxIn& txin, tx.vin)
 361     {
 362         uint256 prevoutHash = txin.prevout.hash;
 363         addInput();
 364         index++;
 365         MultisigInputEntry *entry = qobject_cast<MultisigInputEntry *>(ui->inputs->itemAt(index)->widget());
 366         if(entry)
 367         {
 368             entry->setTransactionId(QString(prevoutHash.GetHex().c_str()));
 369             entry->setTransactionOutputIndex(txin.prevout.n);
 370         }
 371     }
 372
 373     // Fill output list
 374     index = -1;
 375     BOOST_FOREACH(const CTxOut& txout, tx.vout)
 376     {
 377         CScript scriptPubKey = txout.scriptPubKey;
 378         CTxDestination addr;
 379         ExtractDestination(scriptPubKey, addr);
 380         CBitcoinAddress address(addr);
 381         SendCoinsRecipient recipient;
 382         recipient.address = QString(address.ToString().c_str());
 383         recipient.amount = txout.nValue;
 384         addOutput();
 385         index++;
 386         SendCoinsEntry *entry = qobject_cast<SendCoinsEntry *>(ui->outputs->itemAt(index)->widget());
 387         if(entry)
 388         {
 389             entry->setValue(recipient);
 390         }
 391     }
 392
 393     updateRemoveEnabled();
 394 }
 395
 396 void MultisigDialog::on_copyTransactionButton_clicked()
 397 {
 398     QApplication::clipboard()->setText(ui->transaction->text());
 399 }
 400
 401 void MultisigDialog::on_pasteTransactionButton_clicked()
 402 {
 403     ui->transaction->setText(QApplication::clipboard()->text());
 404 }
 405
 406 void MultisigDialog::on_signTransactionButton_clicked()
 407 {
 408     ui->signedTransaction->clear();
 409
 410     if(!model)
 411         return;
 412
 413     CWallet *wallet = model->getWallet();
 414
 415     // Decode the raw transaction
 416     std::vector<unsigned char> txData(ParseHex(ui->transaction->text().toStdString()));
 417     CDataStream ss(txData, SER_NETWORK, PROTOCOL_VERSION);
 418     CTransaction tx;
 419     try
 420     {
 421         ss >> tx;
 422     }
 423     catch(std::exception &e)
 424     {
 425         return;
 426     }
 427     CTransaction mergedTx(tx);
 428
 429     // Fetch previous transactions (inputs)
 430     std::map<COutPoint, CScript> mapPrevOut;
 431     for(unsigned int i = 0; i < mergedTx.vin.size(); i++)
 432     {
 433         CTransaction tempTx;
 434         MapPrevTx mapPrevTx;
 435         CTxDB txdb("r");
 436         std::map<uint256, CTxIndex> unused;
 437         bool fInvalid;
 438
 439         tempTx.vin.push_back(mergedTx.vin[i]);
 440         tempTx.FetchInputs(txdb, unused, false, false, mapPrevTx, fInvalid);
 441
 442         BOOST_FOREACH(const CTxIn& txin, tempTx.vin)
 443         {
 444             const uint256& prevHash = txin.prevout.hash;
 445             if(mapPrevTx.count(prevHash) && mapPrevTx[prevHash].second.vout.size() > txin.prevout.n)
 446                 mapPrevOut[txin.prevout] = mapPrevTx[prevHash].second.vout[txin.prevout.n].scriptPubKey;
 447         }
 448     }
 449
 450     // Add the redeem scripts to the wallet keystore
 451     for(int i = 0; i < ui->inputs->count(); i++)
 452     {
 453         MultisigInputEntry *entry = qobject_cast<MultisigInputEntry *>(ui->inputs->itemAt(i)->widget());
 454         if(entry)
 455         {
 456             QString redeemScriptStr = entry->getRedeemScript();
 457             if(redeemScriptStr.size() > 0)
 458             {
 459                 std::vector<unsigned char> scriptData(ParseHex(redeemScriptStr.toStdString()));
 460                 CScript redeemScript(scriptData.begin(), scriptData.end());
 461                 wallet->AddCScript(redeemScript);
 462             }
 463         }
 464     }
 465
 466     WalletModel::UnlockContext ctx(model->requestUnlock());
 467     if(!ctx.isValid())
 468         return;
 469
 470     // Sign what we can
 471     bool fComplete = true;
 472     for(unsigned int i = 0; i < mergedTx.vin.size(); i++)
 473     {
 474         CTxIn& txin = mergedTx.vin[i];
 475         if(mapPrevOut.count(txin.prevout) == 0)
 476         {
 477             fComplete = false;
 478             continue;
 479         }
 480         const CScript& prevPubKey = mapPrevOut[txin.prevout];
 481
 482         txin.scriptSig.clear();
 483         SignSignature(*wallet, prevPubKey, mergedTx, i, SIGHASH_ALL);
 484         txin.scriptSig = CombineSignatures(prevPubKey, mergedTx, i, txin.scriptSig, tx.vin[i].scriptSig);
 485         if(!VerifyScript(txin.scriptSig, prevPubKey, mergedTx, i, true, 0))
 486         {
 487             fComplete = false;
 488         }
 489     }
 490
 491     CDataStream ssTx(SER_NETWORK, PROTOCOL_VERSION);
 492     ssTx << mergedTx;
 493     ui->signedTransaction->setText(HexStr(ssTx.begin(), ssTx.end()).c_str());
 494
 495     if(fComplete)
 496     {
 497         ui->statusLabel->setText(tr("Transaction signature is complete"));
 498         ui->sendTransactionButton->setEnabled(true);
 499     }
 500     else
 501     {
 502         ui->statusLabel->setText(tr("Transaction is NOT completely signed"));
 503         ui->sendTransactionButton->setEnabled(false);
 504     }
 505 }
 506
 507 void MultisigDialog::on_copySignedTransactionButton_clicked()
 508 {
 509     QApplication::clipboard()->setText(ui->signedTransaction->text());
 510 }
 511
 512 void MultisigDialog::on_sendTransactionButton_clicked()
 513 {
 514     int64_t transactionSize = ui->signedTransaction->text().size() / 2;
 515     if(transactionSize == 0)
 516         return;
 517
 518     // Check the fee
 519     int64_t fee = (int64_t ) (ui->fee->text().toDouble() * COIN);
 520     int64_t minFee = MIN_TX_FEE * (1 + (int64_t) transactionSize / 1000);
 521     if(fee < minFee)
 522     {
 523         QMessageBox::StandardButton ret = QMessageBox::question(this, tr("Confirm send transaction"), tr("The fee of the transaction (%1 NVC) is smaller than the expected fee (%2 NVC). Do you want to send the transaction anyway?").arg((double) fee / COIN).arg((double) minFee / COIN), QMessageBox::Yes | QMessageBox::Cancel, QMessageBox::Cancel);
 524         if(ret != QMessageBox::Yes)
 525             return;
 526     }
 527     else if(fee > minFee)
 528     {
 529         QMessageBox::StandardButton ret = QMessageBox::question(this, tr("Confirm send transaction"), tr("The fee of the transaction (%1 NVC) is bigger than the expected fee (%2 NVC). Do you want to send the transaction anyway?").arg((double) fee / COIN).arg((double) minFee / COIN), QMessageBox::Yes | QMessageBox::Cancel, QMessageBox::Cancel);
 530         if(ret != QMessageBox::Yes)
 531             return;
 532     }
 533
 534     // Decode the raw transaction
 535     std::vector<unsigned char> txData(ParseHex(ui->signedTransaction->text().toStdString()));
 536     CDataStream ssData(txData, SER_NETWORK, PROTOCOL_VERSION);
 537     CTransaction tx;
 538     try
 539     {
 540         ssData >> tx;
 541     }
 542     catch(std::exception &e)
 543     {
 544         return;
 545     }
 546     uint256 txHash = tx.GetHash();
 547
 548     // Check if the transaction is already in the blockchain
 549     CTransaction existingTx;
 550     uint256 blockHash = 0;
 551     if(GetTransaction(txHash, existingTx, blockHash))
 552     {
 553         if(blockHash != 0)
 554             return;
 555     }
 556
 557     // Send the transaction to the local node
 558     CTxDB txdb("r");
 559     if(!tx.AcceptToMemoryPool(txdb, false))
 560     return;
 561     SyncWithWallets(tx, NULL, true);
 562     //(CInv(MSG_TX, txHash), tx);
 563     RelayTransaction(tx, txHash);
 564 }
 565
 566 MultisigInputEntry * MultisigDialog::addInput()
 567 {
 568     MultisigInputEntry *entry = new MultisigInputEntry(this);
 569
 570     entry->setModel(model);
 571     ui->inputs->addWidget(entry);
 572     connect(entry, SIGNAL(removeEntry(MultisigInputEntry *)), this, SLOT(removeEntry(MultisigInputEntry *)));
 573     connect(entry, SIGNAL(updateAmount()), this, SLOT(updateAmounts()));
 574     updateRemoveEnabled();
 575     entry->clear();
 576     ui->scrollAreaWidgetContents_2->resize(ui->scrollAreaWidgetContents_2->sizeHint());
 577     QScrollBar *bar = ui->scrollArea_2->verticalScrollBar();
 578     if(bar)
 579         bar->setSliderPosition(bar->maximum());
 580
 581     return entry;
 582 }
 583
 584 void MultisigDialog::removeEntry(MultisigInputEntry *entry)
 585 {
 586     delete entry;
 587     updateRemoveEnabled();
 588 }
 589
 590 SendCoinsEntry * MultisigDialog::addOutput()
 591 {
 592     SendCoinsEntry *entry = new SendCoinsEntry(this);
 593
 594     entry->setModel(model);
 595     ui->outputs->addWidget(entry);
 596     connect(entry, SIGNAL(removeEntry(SendCoinsEntry *)), this, SLOT(removeEntry(SendCoinsEntry *)));
 597     connect(entry, SIGNAL(payAmountChanged()), this, SLOT(updateAmounts()));
 598     updateRemoveEnabled();
 599     entry->clear();
 600     ui->scrollAreaWidgetContents_3->resize(ui->scrollAreaWidgetContents_3->sizeHint());
 601     QScrollBar *bar = ui->scrollArea_3->verticalScrollBar();
 602     if(bar)
 603         bar->setSliderPosition(bar->maximum());
 604
 605     return entry;
 606 }
 607
 608 void MultisigDialog::removeEntry(SendCoinsEntry *entry)
 609 {
 610     delete entry;
 611     updateRemoveEnabled();
 612 }
 613
 614 void MultisigDialog::updateAmounts()
 615 {
 616     // Update inputs amount
 617     int64_t inputsAmount = 0;
 618     for(int i = 0; i < ui->inputs->count(); i++)
 619     {
 620         MultisigInputEntry *entry = qobject_cast<MultisigInputEntry *>(ui->inputs->itemAt(i)->widget());
 621         if(entry)
 622             inputsAmount += entry->getAmount();
 623     }
 624     QString inputsAmountStr;
 625     inputsAmountStr.sprintf("%.6f", (double) inputsAmount / COIN);
 626     ui->inputsAmount->setText(inputsAmountStr);
 627
 628     // Update outputs amount
 629     int64_t outputsAmount = 0;
 630     for(int i = 0; i < ui->outputs->count(); i++)
 631     {
 632         SendCoinsEntry *entry = qobject_cast<SendCoinsEntry *>(ui->outputs->itemAt(i)->widget());
 633         if(entry)
 634             outputsAmount += entry->getValue().amount;
 635     }
 636     QString outputsAmountStr;
 637     outputsAmountStr.sprintf("%.6f", (double) outputsAmount / COIN);
 638     ui->outputsAmount->setText(outputsAmountStr);
 639
 640     // Update Fee amount
 641     int64_t fee = inputsAmount - outputsAmount;
 642     QString feeStr;
 643     feeStr.sprintf("%.6f", (double) fee / COIN);
 644     ui->fee->setText(feeStr);
 645 }