SSH Agent: Fix handling of encrypted RSA keys

Also fix multiple UI issues caused by said keys.

Fixes #1560

src/sshagent/OpenSSHKey.cpp

@@ -94,6 +94,10 @@ int OpenSSHKey::keyLength() const
 
 const QString OpenSSHKey::fingerprint() const
 {
+    if (m_publicData.isEmpty()) {
+        return {};
+    }
+
     QByteArray publicKey;
     BinaryStream stream(&publicKey);
 
@@ -115,6 +119,10 @@ const QString OpenSSHKey::comment() const
 
 const QString OpenSSHKey::publicKey() const
 {
+    if (m_publicData.isEmpty()) {
+        return {};
+    }
+
     QByteArray publicKey;
     BinaryStream stream(&publicKey);
 
@@ -326,7 +334,7 @@ bool OpenSSHKey::openPrivateKey(const QString& passphrase)
             return false;
         }
 
-        if (passphrase.length() == 0) {
+        if (passphrase.isEmpty()) {
             m_error = tr("Passphrase is required to decrypt this key");
             return false;
         }

src/sshagent/SSHAgent.cpp

@@ -260,6 +260,10 @@ void SSHAgent::databaseModeChanged(DatabaseWidget::Mode mode)
                 continue;
             }
 
+            if (!key.openPrivateKey(e->password())) {
+                continue;
+            }
+
             if (key.comment().isEmpty()) {
                 key.setComment(e->username());
             }
@@ -268,7 +272,7 @@ void SSHAgent::databaseModeChanged(DatabaseWidget::Mode mode)
                 removeIdentityAtLock(key, uuid);
             }
 
-            if (settings.addAtDatabaseOpen() && key.openPrivateKey(e->password())) {
+            if (settings.addAtDatabaseOpen()) {
                 int lifetime = 0;
 
                 if (settings.useLifetimeConstraintWhenAdding()) {