Merge pull request #375 from greenart7c3/claude/fix-invalid-key-exception-cWPcF

Handle AndroidKeyStore failures and display warning to users

app/src/main/java/com/greenart7c3/nostrsigner/Amber.kt

@@ -140,6 +140,9 @@ class Amber :
     val isOnOfflineState = mutableStateOf(false)
     private val isStartingApp = MutableStateFlow(false)
 
+    /** npubs whose AndroidKeyStore key failed to decrypt (device KeyMint bug). */
+    val keystoreFailedAccounts = MutableStateFlow<List<String>>(emptyList())
+
     @Volatile var intentionalDisconnectTime = 0L
     val isStartingAppState = isStartingApp
     val notificationCache = LruCache<String, Long>(10)

app/src/main/java/com/greenart7c3/nostrsigner/LocalPreferences.kt

@@ -23,6 +23,8 @@ import com.vitorpamplona.quartz.nip01Core.signers.NostrSignerInternal
 import com.vitorpamplona.quartz.nip19Bech32.toNpub
 import com.vitorpamplona.quartz.utils.cache.LargeCache
 import java.io.File
+import java.security.InvalidKeyException
+import java.security.KeyStoreException
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.runBlocking
 
@@ -201,7 +203,7 @@ object LocalPreferences {
             val torMode = if (contains(SettingsKeys.TOR_MODE.key)) {
                 try {
                     TorMode.valueOf(getString(SettingsKeys.TOR_MODE.key, TorMode.DISABLED.name)!!)
-                } catch (e: IllegalArgumentException) {
+                } catch (_: IllegalArgumentException) {
                     TorMode.DISABLED
                 }
             } else if (getBoolean(SettingsKeys.USE_PROXY.key, false)) {
@@ -482,11 +484,21 @@ object LocalPreferences {
         if (!containsAccount(context, npub)) {
             return null
         }
-        val privKey = DataStoreAccess.getEncryptedKey(
-            context,
-            npub,
-            DataStoreAccess.NOSTR_PRIVKEY,
-        )
+        val privKey = try {
+            DataStoreAccess.getEncryptedKey(
+                context,
+                npub,
+                DataStoreAccess.NOSTR_PRIVKEY,
+            )
+        } catch (e: InvalidKeyException) {
+            Log.e(Amber.TAG, "AndroidKeyStore key for $npub is broken (device KeyMint may not support key upgrade). Account skipped.", e)
+            Amber.instance.keystoreFailedAccounts.value = (Amber.instance.keystoreFailedAccounts.value + npub).distinct()
+            return null
+        } catch (e: KeyStoreException) {
+            Log.e(Amber.TAG, "KeyStore operation failed for $npub. Account skipped.", e)
+            Amber.instance.keystoreFailedAccounts.value = (Amber.instance.keystoreFailedAccounts.value + npub).distinct()
+            return null
+        }
         sharedPrefs(context, npub).apply {
             val pubKey = getString(PrefKeys.NOSTR_PUBKEY.key, null) ?: return null
             val name = getString(PrefKeys.ACCOUNT_NAME.key, "") ?: ""

app/src/main/java/com/greenart7c3/nostrsigner/ui/AccountScreen.kt

@@ -24,6 +24,8 @@ import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.Color
@@ -32,6 +34,7 @@ import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.unit.dp
 import androidx.navigation.NavHostController
 import androidx.navigation.compose.rememberNavController
+import com.greenart7c3.nostrsigner.Amber
 import com.greenart7c3.nostrsigner.MainViewModel
 import com.greenart7c3.nostrsigner.R
 import com.greenart7c3.nostrsigner.models.AmberBunkerRequest
@@ -56,6 +59,8 @@ fun AccountScreen(
     val accountState by accountStateViewModel.accountContent.collectAsState()
     val context = LocalContext.current
 
+    KeystoreFailureWarning()
+
     Column {
         Crossfade(
             targetState = accountState,
@@ -119,6 +124,22 @@ fun AccountScreen(
     }
 }
 
+@Composable
+private fun KeystoreFailureWarning() {
+    val failedAccounts by Amber.instance.keystoreFailedAccounts.collectAsState()
+    var dismissed by remember { mutableStateOf(false) }
+
+    if (failedAccounts.isNotEmpty() && !dismissed) {
+        val accountList = failedAccounts.joinToString("\n") { "• ${it.take(12)}…" }
+        InformationDialog(
+            title = stringResource(R.string.keystore_error_title),
+            textContent = stringResource(R.string.keystore_error_message, accountList),
+        ) {
+            dismissed = true
+        }
+    }
+}
+
 @Composable
 private fun DisplayErrorMessages() {
     val openDialogMsg = ToastManager.toasts.collectAsState(null)

app/src/main/res/values/strings.xml

@@ -693,4 +693,6 @@
     <string name="auth_whitelist_description">When the whitelist is non-empty, relay client authentication (NIP-42) will only be allowed for relays in the list. Auth requests from other relays will be rejected automatically.</string>
     <string name="add_relay_to_whitelist">Add relay to whitelist</string>
     <string name="relay_not_in_auth_whitelist">Relay is not in the auth whitelist</string>
+    <string name="keystore_error_title">Account Inaccessible</string>
+    <string name="keystore_error_message">One or more accounts could not be loaded because your device\'s secure storage (KeyStore) returned an error:\n\n%1$s\n\nThis is a known firmware bug on some devices where the system cannot upgrade stored encryption keys.\n\nWhat you can do:\n• If you have your nsec (private key) backed up, log out of the affected account and log back in — this will create a new working key.\n• Check for a system firmware update from your device manufacturer, which may fix this.\n• Do not uninstall Amber; keeping the app installed preserves the possibility of recovery if a firmware update is released.</string>
 </resources>