From f2447e4c8676effb4eba91a3e6d3c49a86a9c4b7 Mon Sep 17 00:00:00 2001
From: Sylvain Berfini <sylvain.berfini@belledonne-communications.com>
Date: Fri, 22 Oct 2021 11:38:27 +0200
Subject: [PATCH] Trying to prevent crash due to unusable key store master key

---
 .../java/org/linphone/core/CoreContext.kt     | 11 +++++--
 .../java/org/linphone/core/CorePreferences.kt | 31 +++++++++++++------
 2 files changed, 30 insertions(+), 12 deletions(-)

diff --git a/app/src/main/java/org/linphone/core/CoreContext.kt b/app/src/main/java/org/linphone/core/CoreContext.kt
index e15cd3885..8e942a1a8 100644
--- a/app/src/main/java/org/linphone/core/CoreContext.kt
+++ b/app/src/main/java/org/linphone/core/CoreContext.kt
@@ -883,11 +883,16 @@ class CoreContext(val context: Context, coreConfig: Config) {
         fun activateVFS() {
             try {
                 Log.i("[Context] Activating VFS")
+                val preferences = corePreferences.encryptedSharedPreferences
+                if (preferences == null) {
+                    Log.e("[Context] Can't get encrypted SharedPreferences, can't init VFS")
+                    return
+                }
 
-                if (corePreferences.encryptedSharedPreferences.getString(VFS_IV, null) == null) {
+                if (preferences.getString(VFS_IV, null) == null) {
                     generateSecretKey()
                     encryptToken(generateToken()).let { data ->
-                        corePreferences.encryptedSharedPreferences
+                        preferences
                             .edit()
                             .putString(VFS_IV, data.first)
                             .putString(VFS_KEY, data.second)
@@ -896,7 +901,7 @@ class CoreContext(val context: Context, coreConfig: Config) {
                 }
                 Factory.instance().setVfsEncryption(
                     LINPHONE_VFS_ENCRYPTION_AES256GCM128_SHA256,
-                    getVfsKey(corePreferences.encryptedSharedPreferences).toByteArray().copyOfRange(0, 32),
+                    getVfsKey(preferences).toByteArray().copyOfRange(0, 32),
                     32
                 )
 
diff --git a/app/src/main/java/org/linphone/core/CorePreferences.kt b/app/src/main/java/org/linphone/core/CorePreferences.kt
index f951dd85f..aca0f4e1d 100644
--- a/app/src/main/java/org/linphone/core/CorePreferences.kt
+++ b/app/src/main/java/org/linphone/core/CorePreferences.kt
@@ -26,6 +26,7 @@ import androidx.security.crypto.MasterKey
 import java.io.File
 import java.io.FileInputStream
 import java.io.FileOutputStream
+import java.security.KeyStoreException
 import org.linphone.LinphoneApplication.Companion.coreContext
 import org.linphone.compatibility.Compatibility
 import org.linphone.core.tools.Log
@@ -46,26 +47,38 @@ class CorePreferences constructor(private val context: Context) {
         private const val encryptedSharedPreferencesFile = "encrypted.pref"
     }
 
-    val encryptedSharedPreferences: SharedPreferences by lazy {
+    val encryptedSharedPreferences: SharedPreferences? by lazy {
         val masterKey: MasterKey = MasterKey.Builder(
             context,
             MasterKey.DEFAULT_MASTER_KEY_ALIAS
         ).setKeyScheme(MasterKey.KeyScheme.AES256_GCM).build()
-        EncryptedSharedPreferences.create(
-            context, encryptedSharedPreferencesFile, masterKey,
-            EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
-            EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
-        )
+        try {
+            EncryptedSharedPreferences.create(
+                context, encryptedSharedPreferencesFile, masterKey,
+                EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
+                EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
+            )
+        } catch (kse: KeyStoreException) {
+            Log.e("[VFS] Keystore exception: $kse")
+            null
+        }
     }
 
     var vfsEnabled: Boolean
-        get() = encryptedSharedPreferences.getBoolean("vfs_enabled", false)
+        get() = encryptedSharedPreferences?.getBoolean("vfs_enabled", false) ?: false
         set(value) {
-            if (!value && encryptedSharedPreferences.getBoolean("vfs_enabled", false)) {
+            val preferences = encryptedSharedPreferences
+            if (preferences == null) {
+                Log.e("[VFS] Failed to get encrypted SharedPreferences")
+                return
+            }
+
+            if (!value && preferences.getBoolean("vfs_enabled", false)) {
                 Log.w("[VFS] It is not possible to disable VFS once it has been enabled")
                 return
             }
-            encryptedSharedPreferences.edit().putBoolean("vfs_enabled", value).apply()
+
+            preferences.edit().putBoolean("vfs_enabled", value)?.apply()
             // When VFS is enabled we disable logcat output for linphone logs
             // TODO: decide if we do it
             // logcatLogsOutput = false