From 8ba90f266eed863dd5e6c13d60c21b380e0272de Mon Sep 17 00:00:00 2001
From: Daniel Gultsch <daniel@gultsch.de>
Date: Wed, 20 Sep 2023 17:00:04 +0200
Subject: [PATCH] add explicit error message for outdated backup files

---
 .../ui/ImportBackupActivity.java              |  3 +++
 .../conversations/utils/BackupFileHeader.java | 22 ++++++++++++-------
 src/main/res/values/strings.xml               |  1 +
 3 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/src/conversations/java/eu/siacs/conversations/ui/ImportBackupActivity.java b/src/conversations/java/eu/siacs/conversations/ui/ImportBackupActivity.java
index 6e4815159cd4ab8283d8836ae0f5582ed12d0563..ed998677b31ab2e45c915b88decf48cdadb708dd 100644
--- a/src/conversations/java/eu/siacs/conversations/ui/ImportBackupActivity.java
+++ b/src/conversations/java/eu/siacs/conversations/ui/ImportBackupActivity.java
@@ -30,6 +30,7 @@ import eu.siacs.conversations.databinding.DialogEnterPasswordBinding;
 import eu.siacs.conversations.services.ImportBackupService;
 import eu.siacs.conversations.ui.adapter.BackupFileAdapter;
 import eu.siacs.conversations.ui.util.SettingsUtils;
+import eu.siacs.conversations.utils.BackupFileHeader;
 import eu.siacs.conversations.utils.ThemeHelper;
 
 public class ImportBackupActivity extends ActionBarActivity implements ServiceConnection, ImportBackupService.OnBackupFilesLoaded, BackupFileAdapter.OnItemClickedListener, ImportBackupService.OnBackupProcessed {
@@ -131,6 +132,8 @@ public class ImportBackupActivity extends ActionBarActivity implements ServiceCo
         try {
             final ImportBackupService.BackupFile backupFile = ImportBackupService.BackupFile.read(this, uri);
             showEnterPasswordDialog(backupFile, finishOnCancel);
+        } catch (final BackupFileHeader.OutdatedBackupFileVersion e) {
+            Snackbar.make(binding.coordinator, R.string.outdated_backup_file_format, Snackbar.LENGTH_LONG).show();
         } catch (final IOException | IllegalArgumentException e) {
             Log.d(Config.LOGTAG, "unable to open backup file " + uri, e);
             Snackbar.make(binding.coordinator, R.string.not_a_backup_file, Snackbar.LENGTH_LONG).show();
diff --git a/src/main/java/eu/siacs/conversations/utils/BackupFileHeader.java b/src/main/java/eu/siacs/conversations/utils/BackupFileHeader.java
index 957ccfca157c44e3abd4e917324a741bac15f69b..3b536c27a89c5f874ae7181ea9cd20b10dc860fb 100644
--- a/src/main/java/eu/siacs/conversations/utils/BackupFileHeader.java
+++ b/src/main/java/eu/siacs/conversations/utils/BackupFileHeader.java
@@ -50,17 +50,19 @@ public class BackupFileHeader {
 
     public static BackupFileHeader read(DataInputStream inputStream) throws IOException {
         final int version = inputStream.readInt();
-        if (version != VERSION) {
-            throw new IllegalArgumentException("Backup File version was " + version + " but app only supports version " + VERSION);
-        }
-        String app = inputStream.readUTF();
-        String jid = inputStream.readUTF();
+        final String app = inputStream.readUTF();
+        final String jid = inputStream.readUTF();
         long timestamp = inputStream.readLong();
-        byte[] iv = new byte[12];
+        final byte[] iv = new byte[12];
         inputStream.readFully(iv);
-        byte[] salt = new byte[16];
+        final byte[] salt = new byte[16];
         inputStream.readFully(salt);
-
+        if (version < VERSION) {
+            throw new OutdatedBackupFileVersion();
+        }
+        if (version != VERSION) {
+            throw new IllegalArgumentException("Backup File version was " + version + " but app only supports version " + VERSION);
+        }
         return new BackupFileHeader(app, Jid.of(jid), timestamp, iv, salt);
 
     }
@@ -84,4 +86,8 @@ public class BackupFileHeader {
     public long getTimestamp() {
         return timestamp;
     }
+
+    public static class OutdatedBackupFileVersion extends RuntimeException {
+
+    }
 }
diff --git a/src/main/res/values/strings.xml b/src/main/res/values/strings.xml
index d3af22e1584be0b94182c82727405643b9f27bc4..84b2cb61ed370f017f96566dbd53b43b3b0e6e2a 100644
--- a/src/main/res/values/strings.xml
+++ b/src/main/res/values/strings.xml
@@ -894,6 +894,7 @@
     <string name="event">Event</string>
     <string name="open_backup">Open backup</string>
     <string name="not_a_backup_file">The file you selected is not a Conversations backup file</string>
+    <string name="outdated_backup_file_format">You are trying to import an outdated backup file format</string>
     <string name="account_already_setup">This account has already been setup</string>
     <string name="please_enter_password">Please enter the password for this account</string>
     <string name="unable_to_perform_this_action">Could not perform this action</string>