Merge bitcoin-core/gui#738: Add menu option to migrate a wallet

48aae2c gui: Add File > Migrate Wallet (Andrew Chow)
577be88 gui: Optionally return passphrase after unlocking (Andrew Chow)
5b3a85b interfaces, wallet: Expose migrate wallet (Andrew Chow)

Pull request description:

  GUI users need to be able to migrate wallets without going to the RPC console.

ACKs for top commit:
  jarolrod:
    ACK 48aae2c
  pablomartin4btc:
    tACK 48aae2c
  hebasto:
    ACK 48aae2c

Tree-SHA512: 2d02b1e85e7d6cfbf503f417f150cdaa0c63822942e9a6fe28c0ad3e7f40a957bb01a375c909a60432dc600e84574881aa446c7ec983b56f0bb23f07ef15de54

Author: hebasto

src/interfaces/wallet.h

@@ -51,6 +51,7 @@ struct WalletBalances;
 struct WalletTx;
 struct WalletTxOut;
 struct WalletTxStatus;
+struct WalletMigrationResult;
 
 using WalletOrderForm = std::vector<std::pair<std::string, std::string>>;
 using WalletValueMap = std::map<std::string, std::string>;
@@ -333,6 +334,9 @@ class WalletLoader : public ChainClient
     //! Restore backup wallet
     virtual util::Result<std::unique_ptr<Wallet>> restoreWallet(const fs::path& backup_file, const std::string& wallet_name, std::vector<bilingual_str>& warnings) = 0;
 
+    //! Migrate a wallet
+    virtual util::Result<WalletMigrationResult> migrateWallet(const std::string& name, const SecureString& passphrase) = 0;
+
     //! Return available wallets in wallet directory.
     virtual std::vector<std::string> listWalletDir() = 0;
 
@@ -424,6 +428,15 @@ struct WalletTxOut
     bool is_spent = false;
 };
 
+//! Migrated wallet info
+struct WalletMigrationResult
+{
+    std::unique_ptr<Wallet> wallet;
+    std::optional<std::string> watchonly_wallet_name;
+    std::optional<std::string> solvables_wallet_name;
+    fs::path backup_path;
+};
+
 //! Return implementation of Wallet interface. This function is defined in
 //! dummywallet.cpp and throws if the wallet component is not compiled.
 std::unique_ptr<Wallet> MakeWallet(wallet::WalletContext& context, const std::shared_ptr<wallet::CWallet>& wallet);

src/qt/askpassphrasedialog.cpp

@@ -167,6 +167,9 @@ void AskPassphraseDialog::accept()
                                              "passphrase to avoid this issue in the future."));
                 }
             } else {
+                if (m_passphrase_out) {
+                    m_passphrase_out->assign(oldpass);
+                }
                 QDialog::accept(); // Success
             }
         } catch (const std::runtime_error& e) {

src/qt/bitcoingui.cpp

@@ -359,6 +359,10 @@ void BitcoinGUI::createActions()
     m_close_all_wallets_action = new QAction(tr("Close All Wallets…"), this);
     m_close_all_wallets_action->setStatusTip(tr("Close all wallets"));
 
+    m_migrate_wallet_action = new QAction(tr("Migrate Wallet"), this);
+    m_migrate_wallet_action->setEnabled(false);
+    m_migrate_wallet_action->setStatusTip(tr("Migrate a wallet"));
+
     showHelpMessageAction = new QAction(tr("&Command-line options"), this);
     showHelpMessageAction->setMenuRole(QAction::NoRole);
     showHelpMessageAction->setStatusTip(tr("Show the %1 help message to get a list with possible Bitcoin command-line options").arg(PACKAGE_NAME));
@@ -459,6 +463,11 @@ void BitcoinGUI::createActions()
         connect(m_close_all_wallets_action, &QAction::triggered, [this] {
             m_wallet_controller->closeAllWallets(this);
         });
+        connect(m_migrate_wallet_action, &QAction::triggered, [this] {
+            auto activity = new MigrateWalletActivity(m_wallet_controller, this);
+            connect(activity, &MigrateWalletActivity::migrated, this, &BitcoinGUI::setCurrentWallet);
+            activity->migrate(walletFrame->currentWalletModel());
+        });
         connect(m_mask_values_action, &QAction::toggled, this, &BitcoinGUI::setPrivacy);
         connect(m_mask_values_action, &QAction::toggled, this, &BitcoinGUI::enableHistoryAction);
     }
@@ -486,6 +495,7 @@ void BitcoinGUI::createMenuBar()
         file->addAction(m_open_wallet_action);
         file->addAction(m_close_wallet_action);
         file->addAction(m_close_all_wallets_action);
+        file->addAction(m_migrate_wallet_action);
         file->addSeparator();
         file->addAction(backupWalletAction);
         file->addAction(m_restore_wallet_action);
@@ -770,6 +780,7 @@ void BitcoinGUI::setCurrentWallet(WalletModel* wallet_model)
         }
     }
     updateWindowTitle();
+    m_migrate_wallet_action->setEnabled(wallet_model->wallet().isLegacy());
 }
 
 void BitcoinGUI::setCurrentWalletBySelectorIndex(int index)
@@ -803,6 +814,7 @@ void BitcoinGUI::setWalletActionsEnabled(bool enabled)
     openAction->setEnabled(enabled);
     m_close_wallet_action->setEnabled(enabled);
     m_close_all_wallets_action->setEnabled(enabled);
+    m_migrate_wallet_action->setEnabled(enabled);
 }
 
 void BitcoinGUI::createTrayIcon()

src/qt/bitcoingui.h

@@ -163,6 +163,8 @@ class BitcoinGUI : public QMainWindow
     QAction* m_wallet_selector_label_action = nullptr;
     QAction* m_wallet_selector_action = nullptr;
     QAction* m_mask_values_action{nullptr};
+    QAction* m_migrate_wallet_action{nullptr};
+    QMenu* m_migrate_wallet_menu{nullptr};
 
     QLabel *m_wallet_selector_label = nullptr;
     QComboBox* m_wallet_selector = nullptr;

src/qt/walletcontroller.cpp

@@ -435,3 +435,67 @@ void RestoreWalletActivity::finish()
 
     Q_EMIT finished();
 }
+
+void MigrateWalletActivity::migrate(WalletModel* wallet_model)
+{
+    // Warn the user about migration
+    QMessageBox box(m_parent_widget);
+    box.setWindowTitle(tr("Migrate wallet"));
+    box.setText(tr("Are you sure you wish to migrate the wallet <i>%1</i>?").arg(GUIUtil::HtmlEscape(wallet_model->getDisplayName())));
+    box.setInformativeText(tr("Migrating the wallet will convert this wallet to one or more descriptor wallets. A new wallet backup will need to be made.\n"
+                "If this wallet contains any watchonly scripts, a new wallet will be created which contains those watchonly scripts.\n"
+                "If this wallet contains any solvable but not watched scripts, a different and new wallet will be created which contains those scripts.\n\n"
+                "The migration process will create a backup of the wallet before migrating. This backup file will be named "
+                "<wallet name>-<timestamp>.legacy.bak and can be found in the directory for this wallet. In the event of "
+                "an incorrect migration, the backup can be restored with the \"Restore Wallet\" functionality."));
+    box.setStandardButtons(QMessageBox::Yes|QMessageBox::Cancel);
+    box.setDefaultButton(QMessageBox::Yes);
+    if (box.exec() != QMessageBox::Yes) return;
+
+    // Get the passphrase if it is encrypted regardless of it is locked or unlocked. We need the passphrase itself.
+    SecureString passphrase;
+    WalletModel::EncryptionStatus enc_status = wallet_model->getEncryptionStatus();
+    if (enc_status == WalletModel::EncryptionStatus::Locked || enc_status == WalletModel::EncryptionStatus::Unlocked) {
+        AskPassphraseDialog dlg(AskPassphraseDialog::Unlock, m_parent_widget, &passphrase);
+        dlg.setModel(wallet_model);
+        dlg.exec();
+    }
+
+    // GUI needs to remove the wallet so that it can actually be unloaded by migration
+    const std::string name = wallet_model->wallet().getWalletName();
+    m_wallet_controller->removeAndDeleteWallet(wallet_model);
+
+    showProgressDialog(tr("Migrate Wallet"), tr("Migrating Wallet <b>%1</b>…").arg(GUIUtil::HtmlEscape(name)));
+
+    QTimer::singleShot(0, worker(), [this, name, passphrase] {
+        auto res{node().walletLoader().migrateWallet(name, passphrase)};
+
+        if (res) {
+            m_success_message = tr("The wallet '%1' was migrated successfully.").arg(GUIUtil::HtmlEscape(res->wallet->getWalletName()));
+            if (res->watchonly_wallet_name) {
+                m_success_message += tr(" Watchonly scripts have been migrated to a new wallet named '%1'.").arg(GUIUtil::HtmlEscape(res->watchonly_wallet_name.value()));
+            }
+            if (res->solvables_wallet_name) {
+                m_success_message += tr(" Solvable but not watched scripts have been migrated to a new wallet named '%1'.").arg(GUIUtil::HtmlEscape(res->solvables_wallet_name.value()));
+            }
+            m_wallet_model = m_wallet_controller->getOrCreateWallet(std::move(res->wallet));
+        } else {
+            m_error_message = util::ErrorString(res);
+        }
+
+        QTimer::singleShot(0, this, &MigrateWalletActivity::finish);
+    });
+}
+
+void MigrateWalletActivity::finish()
+{
+    if (!m_error_message.empty()) {
+        QMessageBox::critical(m_parent_widget, tr("Migration failed"), QString::fromStdString(m_error_message.translated));
+    } else {
+        QMessageBox::information(m_parent_widget, tr("Migration Successful"), m_success_message);
+    }
+
+    if (m_wallet_model) Q_EMIT migrated(m_wallet_model);
+
+    Q_EMIT finished();
+}

src/qt/walletcontroller.h

@@ -40,6 +40,7 @@ class path;
 class AskPassphraseDialog;
 class CreateWalletActivity;
 class CreateWalletDialog;
+class MigrateWalletActivity;
 class OpenWalletActivity;
 class WalletControllerActivity;
 
@@ -65,6 +66,8 @@ class WalletController : public QObject
     void closeWallet(WalletModel* wallet_model, QWidget* parent = nullptr);
     void closeAllWallets(QWidget* parent = nullptr);
 
+    void migrateWallet(WalletModel* wallet_model, QWidget* parent = nullptr);
+
 Q_SIGNALS:
     void walletAdded(WalletModel* wallet_model);
     void walletRemoved(WalletModel* wallet_model);
@@ -83,6 +86,7 @@ class WalletController : public QObject
     std::unique_ptr<interfaces::Handler> m_handler_load_wallet;
 
     friend class WalletControllerActivity;
+    friend class MigrateWalletActivity;
 };
 
 class WalletControllerActivity : public QObject
@@ -175,4 +179,22 @@ class RestoreWalletActivity : public WalletControllerActivity
     void finish();
 };
 
+class MigrateWalletActivity : public WalletControllerActivity
+{
+    Q_OBJECT
+
+public:
+    MigrateWalletActivity(WalletController* wallet_controller, QWidget* parent) : WalletControllerActivity(wallet_controller, parent) {}
+
+    void migrate(WalletModel* wallet_model);
+
+Q_SIGNALS:
+    void migrated(WalletModel* wallet_model);
+
+private:
+    QString m_success_message;
+
+    void finish();
+};
+
 #endif // BITCOIN_QT_WALLETCONTROLLER_H

src/wallet/interfaces.cpp

@@ -41,6 +41,7 @@ using interfaces::Wallet;
 using interfaces::WalletAddress;
 using interfaces::WalletBalances;
 using interfaces::WalletLoader;
+using interfaces::WalletMigrationResult;
 using interfaces::WalletOrderForm;
 using interfaces::WalletTx;
 using interfaces::WalletTxOut;
@@ -630,6 +631,18 @@ class WalletLoaderImpl : public WalletLoader
             return util::Error{error};
         }
     }
+    util::Result<WalletMigrationResult> migrateWallet(const std::string& name, const SecureString& passphrase) override
+    {
+        auto res = wallet::MigrateLegacyToDescriptor(name, passphrase, m_context);
+        if (!res) return util::Error{util::ErrorString(res)};
+        WalletMigrationResult out{
+            .wallet = MakeWallet(m_context, res->wallet),
+            .watchonly_wallet_name = res->watchonly_wallet ? std::make_optional(res->watchonly_wallet->GetName()) : std::nullopt,
+            .solvables_wallet_name = res->solvables_wallet ? std::make_optional(res->solvables_wallet->GetName()) : std::nullopt,
+            .backup_path = res->backup_path,
+        };
+        return {std::move(out)}; // std::move to work around clang bug
+    }
     std::string getWalletDir() override
     {
         return fs::PathToString(GetWalletDir());

src/wallet/wallet.cpp

@@ -4213,7 +4213,7 @@ util::Result<MigrationResult> MigrateLegacyToDescriptor(const std::string& walle
         // Migration successful, unload the wallet locally, then reload it.
         assert(local_wallet.use_count() == 1);
         local_wallet.reset();
-        LoadWallet(context, wallet_name, /*load_on_start=*/std::nullopt, options, status, error, warnings);
+        res.wallet = LoadWallet(context, wallet_name, /*load_on_start=*/std::nullopt, options, status, error, warnings);
         res.wallet_name = wallet_name;
     } else {
         // Migration failed, cleanup

src/wallet/wallet.h

@@ -1087,6 +1087,7 @@ bool RemoveWalletSetting(interfaces::Chain& chain, const std::string& wallet_nam
 
 struct MigrationResult {
     std::string wallet_name;
+    std::shared_ptr<CWallet> wallet;
     std::shared_ptr<CWallet> watchonly_wallet;
     std::shared_ptr<CWallet> solvables_wallet;
     fs::path backup_path;