Fix automatic data reset on for users affected by encryption issues (…

…EXPOSUREAPP-3313, EXPOSUREAPP-3335) (#1433)

* I overlooked that `KeyException` is a subclass of `GeneralSecurityException`.
This causes us to continue with `KeyException` which then fails the message matching test.
As the underlying Tink code throws the GeneralSecurityException first, we check the type of the last exception.

* Add additional specific test cases for nested exceptions.

* The dialog shouldn't automatically dismiss when the user clicks details.
They may not have read the dialog message completely or want to re-read it.

Corona-Warn-App/src/main/java/de/rki/coronawarnapp/ui/main/MainFragment.kt

@@ -66,7 +66,7 @@ class MainFragment : Fragment(R.layout.fragment_main) {
         if (errorResetTool.isResetNoticeToBeShown) {
             RecoveryByResetDialogFactory(this).showDialog(
                 detailsLink = R.string.errors_generic_text_catastrophic_error_encryption_failure,
-                onDismiss = {
+                onPositive = {
                     errorResetTool.isResetNoticeToBeShown = false
                 }
             )

Corona-Warn-App/src/main/java/de/rki/coronawarnapp/util/errors/RecoveryByResetDialogFactory.kt

@@ -14,17 +14,20 @@ class RecoveryByResetDialogFactory(private val fragment: Fragment) {
 
     fun showDialog(
         @StringRes detailsLink: Int,
-        onDismiss: () -> Unit
+        onPositive: () -> Unit
     ) {
-        AlertDialog.Builder(context)
+        val dialog = AlertDialog.Builder(context)
             .setTitle(R.string.errors_generic_headline)
             .setMessage(R.string.errors_generic_text_catastrophic_error_recovery_via_reset)
             .setCancelable(false)
-            .setOnDismissListener { onDismiss() }
-            .setNeutralButton(R.string.errors_generic_button_negative) { _, _ ->
-                ExternalActionHelper.openUrl(fragment, context.getString(detailsLink))
+            .setNeutralButton(R.string.errors_generic_button_negative, null)
+            .setPositiveButton(R.string.errors_generic_button_positive) { _, _ ->
+                onPositive()
             }
-            .setPositiveButton(R.string.errors_generic_button_positive) { _, _ -> }
-            .show()
+            .create()
+        dialog.show()
+        dialog.getButton(AlertDialog.BUTTON_NEUTRAL)?.setOnClickListener {
+            ExternalActionHelper.openUrl(fragment, context.getString(detailsLink))
+        }
     }
 }

Corona-Warn-App/src/main/java/de/rki/coronawarnapp/util/security/EncryptionErrorResetTool.kt

@@ -71,8 +71,8 @@ class EncryptionErrorResetTool @Inject constructor(
         }
         isResetWindowConsumed = true
 
-        val keyException = error.causes().singleOrNull { it is GeneralSecurityException }
-        if (keyException == null) {
+        val keyException = error.causes().lastOrNull()
+        if (keyException == null || keyException !is GeneralSecurityException) {
             Timber.v("Error has no GeneralSecurityException as cause -> no reset.")
             return false
         }

Corona-Warn-App/src/test/java/de/rki/coronawarnapp/util/security/EncryptionResetToolTest.kt

@@ -14,7 +14,9 @@ import org.junit.jupiter.api.Test
 import testhelpers.BaseIOTest
 import testhelpers.preferences.MockSharedPreferences
 import java.io.File
+import java.io.IOException
 import java.security.GeneralSecurityException
+import java.security.KeyException
 import java.security.KeyStoreException
 
 class EncryptionResetToolTest : BaseIOTest() {
@@ -169,6 +171,86 @@ class EncryptionResetToolTest : BaseIOTest() {
         }
     }
 
+    @Test
+    fun `nested exception may have the same base exception type, ie GeneralSecurityException`() {
+        // https://github.com/corona-warn-app/cwa-app-android/issues/642#issuecomment-712188157
+        createMockFiles()
+
+        createInstance().tryResetIfNecessary(
+            KeyException( // subclass of GeneralSecurityException
+                "Permantly failed to instantiate encrypted preferences",
+                SecurityException(
+                    "Could not decrypt key. decryption failed",
+                    GeneralSecurityException("decryption failed")
+                )
+            )
+        ) shouldBe true
+
+        encryptedPrefsFile.exists() shouldBe false
+        encryptedDatabaseFile.exists() shouldBe false
+
+        mockPreferences.dataMapPeek.apply {
+            this["ea1851.reset.performedAt"] shouldNotBe null
+            this["ea1851.reset.windowconsumed"] shouldBe true
+            this["ea1851.reset.shownotice"] shouldBe true
+        }
+    }
+
+    @Test
+    fun `exception check does not care about the first exception type`() {
+        createMockFiles()
+
+        createInstance().tryResetIfNecessary(
+            CwaSecurityException(
+                KeyException( // subclass of GeneralSecurityException
+                    "Permantly failed to instantiate encrypted preferences",
+                    SecurityException(
+                        "Could not decrypt key. decryption failed",
+                        GeneralSecurityException("decryption failed")
+                    )
+                )
+            )
+        ) shouldBe true
+
+        encryptedPrefsFile.exists() shouldBe false
+        encryptedDatabaseFile.exists() shouldBe false
+
+        mockPreferences.dataMapPeek.apply {
+            this["ea1851.reset.performedAt"] shouldNotBe null
+            this["ea1851.reset.windowconsumed"] shouldBe true
+            this["ea1851.reset.shownotice"] shouldBe true
+        }
+    }
+
+    @Test
+    fun `exception check DOES care about the most nested exception`() {
+        createMockFiles()
+
+        createInstance().tryResetIfNecessary(
+            CwaSecurityException(
+                KeyException( // subclass of GeneralSecurityException
+                    "Permantly failed to instantiate encrypted preferences",
+                    SecurityException(
+                        "Could not decrypt key. decryption failed",
+                        GeneralSecurityException(
+                            "decryption failed",
+                            IOException("I am unexpeted")
+                        )
+                    )
+                )
+            )
+        ) shouldBe false
+
+        encryptedPrefsFile.exists() shouldBe true
+        encryptedDatabaseFile.exists() shouldBe true
+
+        mockPreferences.dataMapPeek.apply {
+            this["ea1851.reset.performedAt"] shouldBe null
+            this["ea1851.reset.windowconsumed"] shouldBe true
+            this["ea1851.reset.shownotice"] shouldBe null
+        }
+    }
+
     @Test
     fun `we want only a specific type of GeneralSecurityException`() {
         createMockFiles()