From d5b0556ea258577bcb6b9def48370d04f1f31f33 Mon Sep 17 00:00:00 2001
From: Torsten Grote <t@grobox.de>
Date: Thu, 11 Mar 2021 16:26:02 -0300
Subject: [PATCH] Exclude all our files from backup

Even though we don't allow backup at all, Android seems to go into the direction of overriding this. For now only for device-to-device backups, even though we could not verify this.
---
 briar-android/src/main/AndroidManifest.xml     |  6 +++++-
 .../src/main/res/xml/backup_rules.xml          | 18 ++++++++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)
 create mode 100644 briar-android/src/main/res/xml/backup_rules.xml

diff --git a/briar-android/src/main/AndroidManifest.xml b/briar-android/src/main/AndroidManifest.xml
index b590e7acf..988ea2b6f 100644
--- a/briar-android/src/main/AndroidManifest.xml
+++ b/briar-android/src/main/AndroidManifest.xml
@@ -27,7 +27,10 @@
 	<uses-permission android:name="android.permission.USE_FINGERPRINT" />
 	<uses-permission android:name="android.permission.VIBRATE" />
 	<uses-permission android:name="android.permission.WAKE_LOCK" />
-	<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
+	<uses-permission
+		android:name="android.permission.WRITE_EXTERNAL_STORAGE"
+		android:maxSdkVersion="18"
+		tools:ignore="ScopedStorage" />
 
 	<uses-permission-sdk-23 android:name="android.permission.ACCESS_FINE_LOCATION" />
 	<uses-permission-sdk-23 android:name="android.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS" />
@@ -38,6 +41,7 @@
 		android:name="org.briarproject.briar.android.BriarApplicationImpl"
 		android:allowBackup="false"
 		android:banner="@mipmap/tv_banner"
+		android:fullBackupContent="@xml/backup_rules"
 		android:icon="@mipmap/ic_launcher_round"
 		android:label="@string/app_name"
 		android:logo="@mipmap/ic_launcher_round"
diff --git a/briar-android/src/main/res/xml/backup_rules.xml b/briar-android/src/main/res/xml/backup_rules.xml
new file mode 100644
index 000000000..200b2d3cd
--- /dev/null
+++ b/briar-android/src/main/res/xml/backup_rules.xml
@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<full-backup-content>
+	<!-- docs: https://developer.android.com/guide/topics/data/autobackup#XMLSyntax -->
+	<exclude
+		domain="root"
+		path="." />
+	<!-- the previous entry should exclude things recursively, but we add more just to be sure -->
+	<exclude
+		domain="root"
+		path="app_db" />
+	<exclude
+		domain="root"
+		path="app_key" />
+	<!-- we don't use domain=file (getFilesDir()), but ApplicationInfo#dataDir -->
+	<exclude
+		domain="sharedpref"
+		path="." />
+</full-backup-content>