Only request mnemonic when user explicitly wants to enable E2EE

Signed-off-by: Claudio Cambra <claudio.cambra@nextcloud.com>

src/gui/accountsettings.cpp

@@ -258,6 +258,7 @@ void AccountSettings::slotE2eEncryptionGenerateKeys()
 {
     connect(_accountState->account()->e2e(), &ClientSideEncryption::initializationFinished, this, &AccountSettings::slotE2eEncryptionInitializationFinished);
     _accountState->account()->setE2eEncryptionKeysGenerationAllowed(true);
+    _accountState->account()->setAskUserForMnemonic(true);
     _accountState->account()->e2e()->initialize(_accountState->account());
 }
 
@@ -271,6 +272,7 @@ void AccountSettings::slotE2eEncryptionInitializationFinished(bool isNewMnemonic
             displayMnemonic(_accountState->account()->e2e()->_mnemonic);
         }
     }
+    _accountState->account()->setAskUserForMnemonic(false);
 }
 
 void AccountSettings::slotEncryptFolderFinished(int status)

src/libsync/account.cpp

@@ -966,4 +966,14 @@ void Account::setE2eEncryptionKeysGenerationAllowed(bool allowed)
     return _e2eEncryptionKeysGenerationAllowed;
 }
 
+bool Account::askUserForMnemonic() const
+{
+    return _e2eAskUserForMnemonic;
+}
+
+void Account::setAskUserForMnemonic(const bool ask)
+{
+    _e2eAskUserForMnemonic = ask;
+}
+
 } // namespace OCC

src/libsync/account.h

@@ -314,10 +314,13 @@ public:
     void setE2eEncryptionKeysGenerationAllowed(bool allowed);
     [[nodiscard]] bool e2eEncryptionKeysGenerationAllowed() const;
 
+    [[nodiscard]] bool askUserForMnemonic() const;
+
 public slots:
     /// Used when forgetting credentials
     void clearQNAMCache();
     void slotHandleSslErrors(QNetworkReply *, QList<QSslError>);
+    void setAskUserForMnemonic(const bool ask);
 
 signals:
     /// Emitted whenever there's network activity
@@ -370,6 +373,7 @@ private:
     bool _trustCertificates = false;
 
     bool _e2eEncryptionKeysGenerationAllowed = false;
+    bool _e2eAskUserForMnemonic = false;
 
     QWeakPointer<Account> _sharedThis;
     QString _id;

src/libsync/clientsideencryption.cpp

@@ -1248,6 +1248,12 @@ void ClientSideEncryption::encryptPrivateKey(const AccountPtr &account)
 }
 
 void ClientSideEncryption::decryptPrivateKey(const AccountPtr &account, const QByteArray &key) {
+    if (!account->askUserForMnemonic()) {
+        qCDebug(lcCse) << "Not allowed to ask user for mnemonic";
+        emit initializationFinished();
+        return;
+    }
+
     QString msg = tr("Please enter your end-to-end encryption passphrase:<br>"
                      "<br>"
                      "Username: %2<br>"