Automatic key sharing with trusted users

src/Olm.cpp

@@ -9,6 +9,7 @@
 #include "DeviceVerificationFlow.h"
 #include "Logging.h"
 #include "MatrixClient.h"
+#include "UserSettingsPage.h"
 #include "Utils.h"
 
 static const std::string STORAGE_SECRET_KEY("secret");
@@ -519,7 +520,20 @@ handle_key_request_message(const mtx::events::DeviceEvent<mtx::events::msg::KeyR
                 return;
         }
 
-        if (!utils::respondsToKeyRequests(req.content.room_id)) {
+        // check if device is verified
+        auto verificationStatus = cache::verificationStatus(req.sender);
+        bool verifiedDevice     = false;
+        if (verificationStatus &&
+            ChatPage::instance()->userSettings()->shareKeysWithTrustedUsers()) {
+                for (const auto &dev : verificationStatus->verified_devices) {
+                        if (dev == req.content.requesting_device_id) {
+                                verifiedDevice = true;
+                                break;
+                        }
+                }
+        }
+
+        if (!utils::respondsToKeyRequests(req.content.room_id) && !verifiedDevice) {
                 nhlog::crypto()->debug("ignoring all key requests for room {}",
                                        req.content.room_id);
                 return;

src/UserSettingsPage.cpp

@@ -72,6 +72,8 @@ UserSettings::load()
         font_                = settings.value("user/font_family", "default").toString();
         avatarCircles_       = settings.value("user/avatar_circles", true).toBool();
         decryptSidebar_      = settings.value("user/decrypt_sidebar", true).toBool();
+        shareKeysWithTrustedUsers_ =
+          settings.value("user/share_keys_with_trusted_users", true).toBool();
         emojiFont_    = settings.value("user/emoji_font_family", "default").toString();
         baseFontSize_ = settings.value("user/font_size", QFont().pointSizeF()).toDouble();
         presence_ =
@@ -291,6 +293,16 @@ UserSettings::setUseStunServer(bool useStunServer)
         save();
 }
 
+void
+UserSettings::setShareKeysWithTrustedUsers(bool shareKeys)
+{
+        if (shareKeys == shareKeysWithTrustedUsers_)
+                return;
+        shareKeysWithTrustedUsers_ = shareKeys;
+        emit shareKeysWithTrustedUsersChanged(shareKeys);
+        save();
+}
+
 void
 UserSettings::setDefaultAudioSource(const QString &defaultAudioSource)
 {
@@ -374,6 +386,7 @@ UserSettings::save()
 
         settings.setValue("avatar_circles", avatarCircles_);
         settings.setValue("decrypt_sidebar", decryptSidebar_);
+        settings.setValue("share_keys_with_trusted_users", shareKeysWithTrustedUsers_);
         settings.setValue("font_size", baseFontSize_);
         settings.setValue("typing_notifications", typingNotifications_);
         settings.setValue("minor_events", sortByImportance_);
@@ -443,6 +456,7 @@ UserSettingsPage::UserSettingsPage(QSharedPointer<UserSettings> settings, QWidge
         startInTrayToggle_         = new Toggle{this};
         avatarCircles_             = new Toggle{this};
         decryptSidebar_            = new Toggle(this);
+        shareKeysWithTrustedUsers_ = new Toggle(this);
         groupViewToggle_           = new Toggle{this};
         timelineButtonsToggle_     = new Toggle{this};
         typingNotifications_       = new Toggle{this};
@@ -653,6 +667,10 @@ UserSettingsPage::UserSettingsPage(QSharedPointer<UserSettings> settings, QWidge
         formLayout_->addRow(new HorizontalLine{this});
         boxWrap(tr("Device ID"), deviceIdValue_);
         boxWrap(tr("Device Fingerprint"), deviceFingerprintValue_);
+        boxWrap(
+          tr("Share keys with trusted users"),
+          shareKeysWithTrustedUsers_,
+          tr("Automatically replies to key requests from other users, if they are verified."));
         formLayout_->addRow(new HorizontalLine{this});
         formLayout_->addRow(sessionKeysLabel, sessionKeysLayout);
 

src/UserSettingsPage.h

@@ -75,6 +75,8 @@ class UserSettings : public QObject
           bool useStunServer READ useStunServer WRITE setUseStunServer NOTIFY useStunServerChanged)
         Q_PROPERTY(QString defaultAudioSource READ defaultAudioSource WRITE setDefaultAudioSource
                      NOTIFY defaultAudioSourceChanged)
+        Q_PROPERTY(bool shareKeysWithTrustedUsers READ shareKeysWithTrustedUsers WRITE
+                     setShareKeysWithTrustedUsers NOTIFY shareKeysWithTrustedUsersChanged)
 
 public:
         UserSettings();
@@ -113,6 +115,7 @@ public:
         void setPresence(Presence state);
         void setUseStunServer(bool state);
         void setDefaultAudioSource(const QString &deviceName);
+        void setShareKeysWithTrustedUsers(bool state);
 
         QString theme() const { return !theme_.isEmpty() ? theme_ : defaultTheme_; }
         bool messageHoverHighlight() const { return messageHoverHighlight_; }
@@ -140,6 +143,7 @@ public:
         Presence presence() const { return presence_; }
         bool useStunServer() const { return useStunServer_; }
         QString defaultAudioSource() const { return defaultAudioSource_; }
+        bool shareKeysWithTrustedUsers() const { return shareKeysWithTrustedUsers_; }
 
 signals:
         void groupViewStateChanged(bool state);
@@ -164,6 +168,7 @@ signals:
         void presenceChanged(Presence state);
         void useStunServerChanged(bool state);
         void defaultAudioSourceChanged(const QString &deviceName);
+        void shareKeysWithTrustedUsersChanged(bool state);
 
 private:
         // Default to system theme if QT_QPA_PLATFORMTHEME var is set.
@@ -186,6 +191,7 @@ private:
         bool hasAlertOnNotification_;
         bool avatarCircles_;
         bool decryptSidebar_;
+        bool shareKeysWithTrustedUsers_;
         int timelineMaxWidth_;
         double baseFontSize_;
         QString font_;
@@ -248,6 +254,7 @@ private:
         Toggle *avatarCircles_;
         Toggle *useStunServer_;
         Toggle *decryptSidebar_;
+        Toggle *shareKeysWithTrustedUsers_;
         QLabel *deviceFingerprintValue_;
         QLabel *deviceIdValue_;