[gui] load PSBT

co-authored-by: Glenn Willen <gwillen@nerdnet.org>

src/qt/bitcoingui.cpp

@@ -317,6 +317,8 @@ void BitcoinGUI::createActions()
     signMessageAction->setStatusTip(tr("Sign messages with your Bitcoin addresses to prove you own them"));
     verifyMessageAction = new QAction(tr("&Verify message..."), this);
     verifyMessageAction->setStatusTip(tr("Verify messages to ensure they were signed with specified Bitcoin addresses"));
+    m_load_psbt_action = new QAction(tr("Load PSBT..."), this);
+    m_load_psbt_action->setStatusTip(tr("Load Partially Signed Bitcoin Transaction"));
 
     openRPCConsoleAction = new QAction(tr("Node window"), this);
     openRPCConsoleAction->setStatusTip(tr("Open node debugging and diagnostic console"));
@@ -366,6 +368,7 @@ void BitcoinGUI::createActions()
         connect(changePassphraseAction, &QAction::triggered, walletFrame, &WalletFrame::changePassphrase);
         connect(signMessageAction, &QAction::triggered, [this]{ showNormalIfMinimized(); });
         connect(signMessageAction, &QAction::triggered, [this]{ gotoSignMessageTab(); });
+        connect(m_load_psbt_action, &QAction::triggered, [this]{ gotoLoadPSBT(); });
         connect(verifyMessageAction, &QAction::triggered, [this]{ showNormalIfMinimized(); });
         connect(verifyMessageAction, &QAction::triggered, [this]{ gotoVerifyMessageTab(); });
         connect(usedSendingAddressesAction, &QAction::triggered, walletFrame, &WalletFrame::usedSendingAddresses);
@@ -438,6 +441,7 @@ void BitcoinGUI::createMenuBar()
         file->addAction(backupWalletAction);
         file->addAction(signMessageAction);
         file->addAction(verifyMessageAction);
+        file->addAction(m_load_psbt_action);
         file->addSeparator();
     }
     file->addAction(quitAction);
@@ -854,6 +858,10 @@ void BitcoinGUI::gotoVerifyMessageTab(QString addr)
 {
     if (walletFrame) walletFrame->gotoVerifyMessageTab(addr);
 }
+void BitcoinGUI::gotoLoadPSBT()
+{
+    if (walletFrame) walletFrame->gotoLoadPSBT();
+}
 #endif // ENABLE_WALLET
 
 void BitcoinGUI::updateNetworkState()

src/qt/bitcoingui.h

@@ -135,6 +135,7 @@ class BitcoinGUI : public QMainWindow
     QAction* usedReceivingAddressesAction = nullptr;
     QAction* signMessageAction = nullptr;
     QAction* verifyMessageAction = nullptr;
+    QAction* m_load_psbt_action = nullptr;
     QAction* aboutAction = nullptr;
     QAction* receiveCoinsAction = nullptr;
     QAction* receiveCoinsMenuAction = nullptr;
@@ -270,6 +271,8 @@ public Q_SLOTS:
     void gotoSignMessageTab(QString addr = "");
     /** Show Sign/Verify Message dialog and switch to verify message tab */
     void gotoVerifyMessageTab(QString addr = "");
+    /** Show load Partially Signed Bitcoin Transaction dialog */
+    void gotoLoadPSBT();
 
     /** Show open dialog */
     void openClicked();

src/qt/walletframe.cpp

@@ -163,6 +163,14 @@ void WalletFrame::gotoVerifyMessageTab(QString addr)
         walletView->gotoVerifyMessageTab(addr);
 }
 
+void WalletFrame::gotoLoadPSBT()
+{
+    WalletView *walletView = currentWalletView();
+    if (walletView) {
+        walletView->gotoLoadPSBT();
+    }
+}
+
 void WalletFrame::encryptWallet(bool status)
 {
     WalletView *walletView = currentWalletView();

src/qt/walletframe.h

@@ -78,6 +78,9 @@ public Q_SLOTS:
     /** Show Sign/Verify Message dialog and switch to verify message tab */
     void gotoVerifyMessageTab(QString addr = "");
 
+    /** Load Partially Signed Bitcoin Transaction */
+    void gotoLoadPSBT();
+
     /** Encrypt the wallet */
     void encryptWallet(bool status);
     /** Backup the wallet */

src/qt/walletview.cpp

@@ -4,6 +4,9 @@
 
 #include <qt/walletview.h>
 
+#include <node/psbt.h>
+#include <node/transaction.h>
+#include <policy/policy.h>
 #include <qt/addressbookpage.h>
 #include <qt/askpassphrasedialog.h>
 #include <qt/clientmodel.h>
@@ -20,6 +23,7 @@
 
 #include <interfaces/node.h>
 #include <ui_interface.h>
+#include <util/strencodings.h>
 
 #include <QAction>
 #include <QActionGroup>
@@ -197,6 +201,80 @@ void WalletView::gotoVerifyMessageTab(QString addr)
         signVerifyMessageDialog->setAddress_VM(addr);
 }
 
+void WalletView::gotoLoadPSBT()
+{
+    QString filename = GUIUtil::getOpenFileName(this,
+        tr("Load Transaction Data"), QString(),
+        tr("Partially Signed Transaction (*.psbt)"), nullptr);
+    if (filename.isEmpty()) return;
+    if (GetFileSize(filename.toLocal8Bit().data(), MAX_FILE_SIZE_PSBT) == MAX_FILE_SIZE_PSBT) {
+        Q_EMIT message(tr("Error"), tr("PSBT file must be smaller than 100 MiB"), CClientUIInterface::MSG_ERROR);
+        return;
+    }
+    std::ifstream in(filename.toLocal8Bit().data(), std::ios::binary);
+    std::string data(std::istreambuf_iterator<char>{in}, {});
+
+    std::string error;
+    PartiallySignedTransaction psbtx;
+    if (!DecodeRawPSBT(psbtx, data, error)) {
+        Q_EMIT message(tr("Error"), tr("Unable to decode PSBT file") + "\n" + QString::fromStdString(error), CClientUIInterface::MSG_ERROR);
+        return;
+    }
+
+    CMutableTransaction mtx;
+    bool complete = false;
+    PSBTAnalysis analysis = AnalyzePSBT(psbtx);
+    QMessageBox msgBox;
+    msgBox.setText("PSBT");
+    switch (analysis.next) {
+    case PSBTRole::CREATOR:
+    case PSBTRole::UPDATER:
+        msgBox.setInformativeText("PSBT is incomplete. Copy to clipboard for manual inspection?");
+        break;
+    case PSBTRole::SIGNER:
+        msgBox.setInformativeText("Transaction needs more signatures. Copy to clipboard?");
+        break;
+    case PSBTRole::FINALIZER:
+    case PSBTRole::EXTRACTOR:
+        complete = FinalizeAndExtractPSBT(psbtx, mtx);
+        if (complete) {
+            msgBox.setInformativeText(tr("Would you like to send this transaction?"));
+        } else {
+            // The analyzer missed something, e.g. if there are final_scriptSig/final_scriptWitness
+            // but with invalid signatures.
+            msgBox.setInformativeText(tr("There was an unexpected problem processing the PSBT. Copy to clipboard for manual inspection?"));
+        }
+    }
+
+    msgBox.setStandardButtons(QMessageBox::Yes | QMessageBox::Cancel);
+    switch (msgBox.exec()) {
+    case QMessageBox::Yes: {
+        if (complete) {
+            std::string err_string;
+            CTransactionRef tx = MakeTransactionRef(mtx);
+
+            TransactionError result = BroadcastTransaction(*clientModel->node().context(), tx, err_string, DEFAULT_MAX_RAW_TX_FEE_RATE.GetFeePerK(), /* relay */ true, /* wait_callback */ false);
+            if (result == TransactionError::OK) {
+                Q_EMIT message(tr("Success"), tr("Broadcasted transaction sucessfully."), CClientUIInterface::MSG_INFORMATION | CClientUIInterface::MODAL);
+            } else {
+                Q_EMIT message(tr("Error"), QString::fromStdString(err_string), CClientUIInterface::MSG_ERROR);
+            }
+        } else {
+            // Serialize the PSBT
+            CDataStream ssTx(SER_NETWORK, PROTOCOL_VERSION);
+            ssTx << psbtx;
+            GUIUtil::setClipboard(EncodeBase64(ssTx.str()).c_str());
+            Q_EMIT message(tr("PSBT copied"), "Copied to clipboard", CClientUIInterface::MSG_INFORMATION);
+            return;
+        }
+    }
+    case QMessageBox::Cancel:
+        break;
+    default:
+        assert(false);
+    }
+}
+
 bool WalletView::handlePaymentRequest(const SendCoinsRecipient& recipient)
 {
     return sendCoinsPage->handlePaymentRequest(recipient);

src/qt/walletview.h

@@ -83,6 +83,8 @@ public Q_SLOTS:
     void gotoSignMessageTab(QString addr = "");
     /** Show Sign/Verify Message dialog and switch to verify message tab */
     void gotoVerifyMessageTab(QString addr = "");
+    /** Load Partially Signed Bitcoin Transaction */
+    void gotoLoadPSBT();
 
     /** Show incoming transaction notification for new transactions.