src/qt/askpassphrasedialog.cpp

   1 // Copyright (c) 2011-2016 The Bitcoin Core developers
   2 // Distributed under the MIT software license, see the accompanying
   3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   4
   5 #if defined(HAVE_CONFIG_H)
   6 #include <config/bitcoin-config.h>
   7 #endif
   8
   9 #include <qt/askpassphrasedialog.h>
  10 #include <qt/forms/ui_askpassphrasedialog.h>
  11
  12 #include <qt/guiconstants.h>
  13 #include <qt/walletmodel.h>
  14
  15 #include <support/allocators/secure.h>
  16
  17 #include <QKeyEvent>
  18 #include <QMessageBox>
  19 #include <QPushButton>
  20
  21 AskPassphraseDialog::AskPassphraseDialog(Mode _mode, QWidget *parent) :
  22     QDialog(parent),
  23     ui(new Ui::AskPassphraseDialog),
  24     mode(_mode),
  25     model(0),
  26     fCapsLock(false)
  27 {
  28     ui->setupUi(this);
  29
  30     ui->passEdit1->setMinimumSize(ui->passEdit1->sizeHint());
  31     ui->passEdit2->setMinimumSize(ui->passEdit2->sizeHint());
  32     ui->passEdit3->setMinimumSize(ui->passEdit3->sizeHint());
  33
  34     ui->passEdit1->setMaxLength(MAX_PASSPHRASE_SIZE);
  35     ui->passEdit2->setMaxLength(MAX_PASSPHRASE_SIZE);
  36     ui->passEdit3->setMaxLength(MAX_PASSPHRASE_SIZE);
  37
  38     // Setup Caps Lock detection.
  39     ui->passEdit1->installEventFilter(this);
  40     ui->passEdit2->installEventFilter(this);
  41     ui->passEdit3->installEventFilter(this);
  42
  43     switch(mode)
  44     {
  45         case Encrypt: // Ask passphrase x2
  46             ui->warningLabel->setText(tr("Enter the new passphrase to the wallet.<br/>Please use a passphrase of <b>ten or more random characters</b>, or <b>eight or more words</b>."));
  47             ui->passLabel1->hide();
  48             ui->passEdit1->hide();
  49             setWindowTitle(tr("Encrypt wallet"));
  50             break;
  51         case Unlock: // Ask passphrase
  52             ui->warningLabel->setText(tr("This operation needs your wallet passphrase to unlock the wallet."));
  53             ui->passLabel2->hide();
  54             ui->passEdit2->hide();
  55             ui->passLabel3->hide();
  56             ui->passEdit3->hide();
  57             setWindowTitle(tr("Unlock wallet"));
  58             break;
  59         case Decrypt:   // Ask passphrase
  60             ui->warningLabel->setText(tr("This operation needs your wallet passphrase to decrypt the wallet."));
  61             ui->passLabel2->hide();
  62             ui->passEdit2->hide();
  63             ui->passLabel3->hide();
  64             ui->passEdit3->hide();
  65             setWindowTitle(tr("Decrypt wallet"));
  66             break;
  67         case ChangePass: // Ask old passphrase + new passphrase x2
  68             setWindowTitle(tr("Change passphrase"));
  69             ui->warningLabel->setText(tr("Enter the old passphrase and new passphrase to the wallet."));
  70             break;
  71     }
  72     textChanged();
  73     connect(ui->toggleShowPasswordButton, SIGNAL(toggled(bool)), this, SLOT(toggleShowPassword(bool)));
  74     connect(ui->passEdit1, SIGNAL(textChanged(QString)), this, SLOT(textChanged()));
  75     connect(ui->passEdit2, SIGNAL(textChanged(QString)), this, SLOT(textChanged()));
  76     connect(ui->passEdit3, SIGNAL(textChanged(QString)), this, SLOT(textChanged()));
  77 }
  78
  79 AskPassphraseDialog::~AskPassphraseDialog()
  80 {
  81     secureClearPassFields();
  82     delete ui;
  83 }
  84
  85 void AskPassphraseDialog::setModel(WalletModel *_model)
  86 {
  87     this->model = _model;
  88 }
  89
  90 void AskPassphraseDialog::accept()
  91 {
  92     SecureString oldpass, newpass1, newpass2;
  93     if(!model)
  94         return;
  95     oldpass.reserve(MAX_PASSPHRASE_SIZE);
  96     newpass1.reserve(MAX_PASSPHRASE_SIZE);
  97     newpass2.reserve(MAX_PASSPHRASE_SIZE);
  98     // TODO: get rid of this .c_str() by implementing SecureString::operator=(std::string)
  99     // Alternately, find a way to make this input mlock()'d to begin with.
 100     oldpass.assign(ui->passEdit1->text().toStdString().c_str());
 101     newpass1.assign(ui->passEdit2->text().toStdString().c_str());
 102     newpass2.assign(ui->passEdit3->text().toStdString().c_str());
 103
 104     secureClearPassFields();
 105
 106     switch(mode)
 107     {
 108     case Encrypt: {
 109         if(newpass1.empty() || newpass2.empty())
 110         {
 111             // Cannot encrypt with empty passphrase
 112             break;
 113         }
 114         QMessageBox::StandardButton retval = QMessageBox::question(this, tr("Confirm wallet encryption"),
 115                  tr("Warning: If you encrypt your wallet and lose your passphrase, you will <b>LOSE ALL OF YOUR BITCOINS</b>!") + "<br><br>" + tr("Are you sure you wish to encrypt your wallet?"),
 116                  QMessageBox::Yes|QMessageBox::Cancel,
 117                  QMessageBox::Cancel);
 118         if(retval == QMessageBox::Yes)
 119         {
 120             if(newpass1 == newpass2)
 121             {
 122                 if(model->setWalletEncrypted(true, newpass1))
 123                 {
 124                     QMessageBox::warning(this, tr("Wallet encrypted"),
 125                                          "<qt>" +
 126                                          tr("%1 will close now to finish the encryption process. "
 127                                          "Remember that encrypting your wallet cannot fully protect "
 128                                          "your bitcoins from being stolen by malware infecting your computer.").arg(tr(PACKAGE_NAME)) +
 129                                          "<br><br><b>" +
 130                                          tr("IMPORTANT: Any previous backups you have made of your wallet file "
 131                                          "should be replaced with the newly generated, encrypted wallet file. "
 132                                          "For security reasons, previous backups of the unencrypted wallet file "
 133                                          "will become useless as soon as you start using the new, encrypted wallet.") +
 134                                          "</b></qt>");
 135                     QApplication::quit();
 136                 }
 137                 else
 138                 {
 139                     QMessageBox::critical(this, tr("Wallet encryption failed"),
 140                                          tr("Wallet encryption failed due to an internal error. Your wallet was not encrypted."));
 141                 }
 142                 QDialog::accept(); // Success
 143             }
 144             else
 145             {
 146                 QMessageBox::critical(this, tr("Wallet encryption failed"),
 147                                      tr("The supplied passphrases do not match."));
 148             }
 149         }
 150         else
 151         {
 152             QDialog::reject(); // Cancelled
 153         }
 154         } break;
 155     case Unlock:
 156         if(!model->setWalletLocked(false, oldpass))
 157         {
 158             QMessageBox::critical(this, tr("Wallet unlock failed"),
 159                                   tr("The passphrase entered for the wallet decryption was incorrect."));
 160         }
 161         else
 162         {
 163             QDialog::accept(); // Success
 164         }
 165         break;
 166     case Decrypt:
 167         if(!model->setWalletEncrypted(false, oldpass))
 168         {
 169             QMessageBox::critical(this, tr("Wallet decryption failed"),
 170                                   tr("The passphrase entered for the wallet decryption was incorrect."));
 171         }
 172         else
 173         {
 174             QDialog::accept(); // Success
 175         }
 176         break;
 177     case ChangePass:
 178         if(newpass1 == newpass2)
 179         {
 180             if(model->changePassphrase(oldpass, newpass1))
 181             {
 182                 QMessageBox::information(this, tr("Wallet encrypted"),
 183                                      tr("Wallet passphrase was successfully changed."));
 184                 QDialog::accept(); // Success
 185             }
 186             else
 187             {
 188                 QMessageBox::critical(this, tr("Wallet encryption failed"),
 189                                      tr("The passphrase entered for the wallet decryption was incorrect."));
 190             }
 191         }
 192         else
 193         {
 194             QMessageBox::critical(this, tr("Wallet encryption failed"),
 195                                  tr("The supplied passphrases do not match."));
 196         }
 197         break;
 198     }
 199 }
 200
 201 void AskPassphraseDialog::textChanged()
 202 {
 203     // Validate input, set Ok button to enabled when acceptable
 204     bool acceptable = false;
 205     switch(mode)
 206     {
 207     case Encrypt: // New passphrase x2
 208         acceptable = !ui->passEdit2->text().isEmpty() && !ui->passEdit3->text().isEmpty();
 209         break;
 210     case Unlock: // Old passphrase x1
 211     case Decrypt:
 212         acceptable = !ui->passEdit1->text().isEmpty();
 213         break;
 214     case ChangePass: // Old passphrase x1, new passphrase x2
 215         acceptable = !ui->passEdit1->text().isEmpty() && !ui->passEdit2->text().isEmpty() && !ui->passEdit3->text().isEmpty();
 216         break;
 217     }
 218     ui->buttonBox->button(QDialogButtonBox::Ok)->setEnabled(acceptable);
 219 }
 220
 221 bool AskPassphraseDialog::event(QEvent *event)
 222 {
 223     // Detect Caps Lock key press.
 224     if (event->type() == QEvent::KeyPress) {
 225         QKeyEvent *ke = static_cast<QKeyEvent *>(event);
 226         if (ke->key() == Qt::Key_CapsLock) {
 227             fCapsLock = !fCapsLock;
 228         }
 229         if (fCapsLock) {
 230             ui->capsLabel->setText(tr("Warning: The Caps Lock key is on!"));
 231         } else {
 232             ui->capsLabel->clear();
 233         }
 234     }
 235     return QWidget::event(event);
 236 }
 237
 238 void AskPassphraseDialog::toggleShowPassword(bool show)
 239 {
 240     ui->toggleShowPasswordButton->setDown(show);
 241     const auto mode = show ? QLineEdit::Normal : QLineEdit::Password;
 242     ui->passEdit1->setEchoMode(mode);
 243     ui->passEdit2->setEchoMode(mode);
 244     ui->passEdit3->setEchoMode(mode);
 245 }
 246
 247 bool AskPassphraseDialog::eventFilter(QObject *object, QEvent *event)
 248 {
 249     /* Detect Caps Lock.
 250      * There is no good OS-independent way to check a key state in Qt, but we
 251      * can detect Caps Lock by checking for the following condition:
 252      * Shift key is down and the result is a lower case character, or
 253      * Shift key is not down and the result is an upper case character.
 254      */
 255     if (event->type() == QEvent::KeyPress) {
 256         QKeyEvent *ke = static_cast<QKeyEvent *>(event);
 257         QString str = ke->text();
 258         if (str.length() != 0) {
 259             const QChar *psz = str.unicode();
 260             bool fShift = (ke->modifiers() & Qt::ShiftModifier) != 0;
 261             if ((fShift && *psz >= 'a' && *psz <= 'z') || (!fShift && *psz >= 'A' && *psz <= 'Z')) {
 262                 fCapsLock = true;
 263                 ui->capsLabel->setText(tr("Warning: The Caps Lock key is on!"));
 264             } else if (psz->isLetter()) {
 265                 fCapsLock = false;
 266                 ui->capsLabel->clear();
 267             }
 268         }
 269     }
 270     return QDialog::eventFilter(object, event);
 271 }
 272
 273 static void SecureClearQLineEdit(QLineEdit* edit)
 274 {
 275     // Attempt to overwrite text so that they do not linger around in memory
 276     edit->setText(QString(" ").repeated(edit->text().size()));
 277     edit->clear();
 278 }
 279
 280 void AskPassphraseDialog::secureClearPassFields()
 281 {
 282     SecureClearQLineEdit(ui->passEdit1);
 283     SecureClearQLineEdit(ui->passEdit2);
 284     SecureClearQLineEdit(ui->passEdit3);
 285 }