feat: support export a single subkey

5 files changed, 157 insertions, 11 deletions

diff --git a/src/core/function/gpg/GpgKeyImportExporter.cpp b/src/core/function/gpg/GpgKeyImportExporter.cpp
index d0494339..fa1f908f 100644
--- a/src/core/function/gpg/GpgKeyImportExporter.cpp
+++ b/src/core/function/gpg/GpgKeyImportExporter.cpp
@@ -174,4 +174,20 @@ void GpgKeyImportExporter::ExportAllKeys(const KeyArgsList& keys, bool secret,
       cb, "gpgme_op_export_keys", "2.1.0");
 }
 
+auto GpgKeyImportExporter::ExportSubkey(const QString& fpr, bool ascii) const
+    -> std::tuple<GpgError, GFBuffer> {
+  int mode = 0;
+  mode |= GPGME_EXPORT_MODE_SECRET_SUBKEY;
+
+  auto pattern = fpr;
+  if (!fpr.endsWith("!")) pattern += "!";
+
+  GpgData data_out;
+  auto* ctx = ascii ? ctx_.DefaultContext() : ctx_.BinaryContext();
+  auto err =
+      gpgme_op_export(ctx, pattern.toLatin1().constData(), mode, data_out);
+  if (gpgme_err_code(err) != GPG_ERR_NO_ERROR) return {err, {}};
+
+  return {err, data_out.Read2GFBuffer()};
+}
 }  // namespace GpgFrontend
diff --git a/src/core/function/gpg/GpgKeyImportExporter.h b/src/core/function/gpg/GpgKeyImportExporter.h
index b52189f1..cc7b3f6f 100644
--- a/src/core/function/gpg/GpgKeyImportExporter.h
+++ b/src/core/function/gpg/GpgKeyImportExporter.h
@@ -75,6 +75,16 @@ class GPGFRONTEND_CORE_EXPORT GpgKeyImportExporter
   /**
    * @brief
    *
+   * @param fpr
+   * @param ascii
+   * @return std::tuple<GpgError, GFBuffer>
+   */
+  [[nodiscard]] auto ExportSubkey(const QString& fpr, bool ascii) const
+      -> std::tuple<GpgError, GFBuffer>;
+
+  /**
+   * @brief
+   *
    * @param keys
    * @param outBuffer
    * @param secret
diff --git a/src/test/core/GpgCoreTestImportExport.cpp b/src/test/core/GpgCoreTestImportExport.cpp
index e67abe78..87e13252 100644
--- a/src/test/core/GpgCoreTestImportExport.cpp
+++ b/src/test/core/GpgCoreTestImportExport.cpp
@@ -26,13 +26,67 @@
  *
  */
 
-#include <vector>
-
 #include "GpgCoreTest.h"
 #include "core/GpgConstants.h"
+#include "core/function/gpg/GpgKeyImportExporter.h"
+#include "core/utils/GpgUtils.h"
 
 namespace GpgFrontend::Test {
 
-// TEST_F(GpgCoreTest, CoreExportSecretTest) {}
+TEST_F(GpgCoreTest, CoreExportSubkeyTestA) {
+  auto [err, gf_buffer] = GpgKeyImportExporter::GetInstance().ExportSubkey(
+      "F89C95A05088CC93", true);
+
+  ASSERT_EQ(CheckGpgError(err), GPG_ERR_NO_ERROR);
+  ASSERT_FALSE(gf_buffer.Empty());
+  ASSERT_EQ(
+      QCryptographicHash::hash(gf_buffer.ConvertToQByteArray(),
+                               QCryptographicHash::Sha256)
+          .toHex(),
+      QByteArray(
+          "6e3375060aa889d9eb61e2966eabb31eb6b5359a7742ee7adeedec09e6afa36a"));
+}
+
+TEST_F(GpgCoreTest, CoreExportSubkeyTestB) {
+  auto [err, gf_buffer] = GpgKeyImportExporter::GetInstance().ExportSubkey(
+      "F89C95A05088CC93!", true);
+
+  ASSERT_EQ(CheckGpgError(err), GPG_ERR_NO_ERROR);
+  ASSERT_FALSE(gf_buffer.Empty());
+  ASSERT_EQ(
+      QCryptographicHash::hash(gf_buffer.ConvertToQByteArray(),
+                               QCryptographicHash::Sha256)
+          .toHex(),
+      QByteArray(
+          "6e3375060aa889d9eb61e2966eabb31eb6b5359a7742ee7adeedec09e6afa36a"));
+}
+
+TEST_F(GpgCoreTest, CoreExportSubkeyTestC) {
+  auto [err, gf_buffer] = GpgKeyImportExporter::GetInstance().ExportSubkey(
+      "CFF986E51BBC2F46064C2136F89C95A05088CC93", true);
+
+  ASSERT_EQ(CheckGpgError(err), GPG_ERR_NO_ERROR);
+  ASSERT_FALSE(gf_buffer.Empty());
+  ASSERT_EQ(
+      QCryptographicHash::hash(gf_buffer.ConvertToQByteArray(),
+                               QCryptographicHash::Sha256)
+          .toHex(),
+      QByteArray(
+          "6e3375060aa889d9eb61e2966eabb31eb6b5359a7742ee7adeedec09e6afa36a"));
+}
+
+TEST_F(GpgCoreTest, CoreExportSubkeyTestD) {
+  auto [err, gf_buffer] = GpgKeyImportExporter::GetInstance().ExportSubkey(
+      "CFF986E51BBC2F46064C2136F89C95A05088CC93!", true);
+
+  ASSERT_EQ(CheckGpgError(err), GPG_ERR_NO_ERROR);
+  ASSERT_FALSE(gf_buffer.Empty());
+  ASSERT_EQ(
+      QCryptographicHash::hash(gf_buffer.ConvertToQByteArray(),
+                               QCryptographicHash::Sha256)
+          .toHex(),
+      QByteArray(
+          "6e3375060aa889d9eb61e2966eabb31eb6b5359a7742ee7adeedec09e6afa36a"));
+}
 
 }  // namespace GpgFrontend::Test
\ No newline at end of file
diff --git a/src/ui/dialog/keypair_details/KeyPairSubkeyTab.cpp b/src/ui/dialog/keypair_details/KeyPairSubkeyTab.cpp
index a5b38d1f..8066ccfb 100644
--- a/src/ui/dialog/keypair_details/KeyPairSubkeyTab.cpp
+++ b/src/ui/dialog/keypair_details/KeyPairSubkeyTab.cpp
@@ -30,8 +30,12 @@
 
 #include "core/GpgModel.h"
 #include "core/function/gpg/GpgKeyGetter.h"
+#include "core/function/gpg/GpgKeyImportExporter.h"
 #include "core/utils/CommonUtils.h"
+#include "core/utils/GpgUtils.h"
+#include "core/utils/IOUtils.h"
 #include "ui/UISignalStation.h"
+#include "ui/UserInterfaceUtils.h"
 
 namespace GpgFrontend::UI {
 
@@ -94,6 +98,10 @@ KeyPairSubkeyTab::KeyPairSubkeyTab(int channel, const QString& key_id,
   fingerprint_var_label_ = new QLabel(this);
   card_key_label_ = new QLabel(this);
 
+  // make keyid & fingerprint selectable for copy
+  key_id_var_label_->setTextInteractionFlags(Qt::TextSelectableByMouse);
+  fingerprint_var_label_->setTextInteractionFlags(Qt::TextSelectableByMouse);
+
   subkey_detail_layout->addWidget(key_id_var_label_, 0, 1, 1, 1);
   subkey_detail_layout->addWidget(algorithm_var_label_, 1, 1, 1, 2);
   subkey_detail_layout->addWidget(algorithm_detail_var_label_, 2, 1, 1, 2);
@@ -105,14 +113,11 @@ KeyPairSubkeyTab::KeyPairSubkeyTab(int channel, const QString& key_id,
   subkey_detail_layout->addWidget(card_key_label_, 8, 1, 1, 2);
   subkey_detail_layout->addWidget(fingerprint_var_label_, 9, 1, 1, 2);
 
-  auto* copy_key_id_button = new QPushButton(tr("Copy"));
-  copy_key_id_button->setFlat(true);
-  subkey_detail_layout->addWidget(copy_key_id_button, 0, 2);
-  connect(copy_key_id_button, &QPushButton::clicked, this, [=]() {
-    QString fpr = key_id_var_label_->text().trimmed();
-    QClipboard* cb = QApplication::clipboard();
-    cb->setText(fpr);
-  });
+  auto* export_subkey_button = new QPushButton(tr("Export Subkey"));
+  export_subkey_button->setFlat(true);
+  subkey_detail_layout->addWidget(export_subkey_button, 0, 2);
+  connect(export_subkey_button, &QPushButton::clicked, this,
+          &KeyPairSubkeyTab::slot_export_subkey);
 
   list_box_->setLayout(subkey_list_layout);
   list_box_->setContentsMargins(0, 12, 0, 0);
@@ -312,6 +317,10 @@ void KeyPairSubkeyTab::create_subkey_opera_menu() {
   connect(edit_subkey_act, &QAction::triggered, this,
           &KeyPairSubkeyTab::slot_edit_subkey);
 
+  auto* export_subkey_act = new QAction(tr("Export"));
+  connect(export_subkey_act, &QAction::triggered, this,
+          &KeyPairSubkeyTab::slot_export_subkey);
+
   subkey_opera_menu_->addAction(edit_subkey_act);
 }
 
@@ -340,10 +349,61 @@ auto KeyPairSubkeyTab::get_selected_subkey() -> const GpgSubKey& {
 
   return buffered_subkeys_[row];
 }
+
 void KeyPairSubkeyTab::slot_refresh_key_info() {
   key_ = GpgKeyGetter::GetInstance(current_gpg_context_channel_)
              .GetKey(key_.GetId());
   assert(key_.IsGood());
 }
 
+void KeyPairSubkeyTab::slot_export_subkey() {
+  int ret = QMessageBox::question(
+      this, tr("Exporting Subkey"),
+      "<h3>" + tr("You are about to export a private subkey.") + "</h3>\n" +
+          tr("While subkeys are less critical than the primary key, "
+             "they should still be handled with care.") +
+          "<br /><br />" +
+          tr("Do you want to proceed with exporting this subkey?"),
+      QMessageBox::Cancel | QMessageBox::Yes, QMessageBox::Cancel);
+
+  if (ret != QMessageBox::Yes) {
+    QMessageBox::information(this, tr("Export Cancelled"),
+                             tr("The subkey export has been cancelled."));
+    return;
+  }
+
+  const auto& subkey = get_selected_subkey();
+
+  auto [err, gf_buffer] =
+      GpgKeyImportExporter::GetInstance(current_gpg_context_channel_)
+          .ExportSubkey(subkey.GetFingerprint(), true);
+
+  if (CheckGpgError(err) != GPG_ERR_NO_ERROR) {
+    CommonUtils::RaiseMessageBox(this, err);
+    return;
+  }
+
+  // generate a file name
+#if defined(_WIN32) || defined(WIN32)
+  auto file_string = key_.GetName() + "[" + key_.GetEmail() + "](" +
+                     subkey.GetID() + ")_subkey.asc";
+#else
+  auto file_string = key_.GetName() + "<" + key_.GetEmail() + ">(" +
+                     subkey.GetID() + ")_subkey.asc";
+#endif
+  std::replace(file_string.begin(), file_string.end(), ' ', '_');
+
+  auto file_name = QFileDialog::getSaveFileName(
+      this, tr("Export Key To File"), file_string,
+      tr("Key Files") + " (*.asc *.txt);;All Files (*)");
+
+  if (file_name.isEmpty()) return;
+
+  if (!WriteFileGFBuffer(file_name, gf_buffer)) {
+    QMessageBox::critical(this, tr("Export Error"),
+                          tr("Couldn't open %1 for writing").arg(file_name));
+    return;
+  }
+}
+
 }  // namespace GpgFrontend::UI
diff --git a/src/ui/dialog/keypair_details/KeyPairSubkeyTab.h b/src/ui/dialog/keypair_details/KeyPairSubkeyTab.h
index 85423745..e7b97eb5 100644
--- a/src/ui/dialog/keypair_details/KeyPairSubkeyTab.h
+++ b/src/ui/dialog/keypair_details/KeyPairSubkeyTab.h
@@ -126,6 +126,12 @@ class KeyPairSubkeyTab : public QWidget {
    */
   void slot_refresh_key_info();
 
+  /**
+   * @brief
+   *
+   */
+  void slot_export_subkey();
+
  protected:
   /**
    * @brief