KeysBackup: Avoid using !!, should fix #2262

CHANGES.md

@@ -21,6 +21,7 @@ Improvements 🙌:
 Bugfix 🐛:
  - Messages encrypted with no way to decrypt after SDK update from 0.18 to 1.0.0 (#2252)
  - Search Result | scroll jumps after pagination (#2238)
+ - KeysBackup: Avoid using `!!` (#2262)
 
 Translations 🗣:
  -

matrix-sdk-android/src/androidTest/java/org/matrix/android/sdk/internal/crypto/keysbackup/KeysBackupTest.kt

@@ -257,14 +257,14 @@ class KeysBackupTest : InstrumentedTest {
         // - Check encryptGroupSession() returns stg
         val keyBackupData = keysBackup.encryptGroupSession(session)
         assertNotNull(keyBackupData)
-        assertNotNull(keyBackupData.sessionData)
+        assertNotNull(keyBackupData!!.sessionData)
 
         // - Check pkDecryptionFromRecoveryKey() is able to create a OlmPkDecryption
         val decryption = keysBackup.pkDecryptionFromRecoveryKey(keyBackupCreationInfo.recoveryKey)
         assertNotNull(decryption)
         // - Check decryptKeyBackupData() returns stg
         val sessionData = keysBackup
-                .decryptKeyBackupData(keyBackupData,
+                .decryptKeyBackupData(keyBackupData!!,
                         session.olmInboundGroupSession!!.sessionIdentifier(),
                         cryptoTestData.roomId,
                         decryption!!)

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/keysbackup/DefaultKeysBackupService.kt

@@ -1212,22 +1212,19 @@ internal class DefaultKeysBackupService @Inject constructor(
 
                 // Gather data to send to the homeserver
                 // roomId -> sessionId -> MXKeyBackupData
-                val keysBackupData = KeysBackupData(
+                val keysBackupData = KeysBackupData()
-                        roomIdToRoomKeysBackupData = HashMap()
-                )
 
-                for (olmInboundGroupSessionWrapper in olmInboundGroupSessionWrappers) {
+                olmInboundGroupSessionWrappers.forEach { olmInboundGroupSessionWrapper ->
-                    val keyBackupData = encryptGroupSession(olmInboundGroupSessionWrapper)
+                    val roomId = olmInboundGroupSessionWrapper.roomId ?: return@forEach
-                    if (keysBackupData.roomIdToRoomKeysBackupData[olmInboundGroupSessionWrapper.roomId] == null) {
+                    val olmInboundGroupSession = olmInboundGroupSessionWrapper.olmInboundGroupSession ?: return@forEach
-                        val roomKeysBackupData = RoomKeysBackupData(
-                                sessionIdToKeyBackupData = HashMap()
-                        )
-                        keysBackupData.roomIdToRoomKeysBackupData[olmInboundGroupSessionWrapper.roomId!!] = roomKeysBackupData
-                    }
 
                     try {
-                        keysBackupData.roomIdToRoomKeysBackupData[olmInboundGroupSessionWrapper.roomId]!!
+                        encryptGroupSession(olmInboundGroupSessionWrapper)
-                                .sessionIdToKeyBackupData[olmInboundGroupSessionWrapper.olmInboundGroupSession!!.sessionIdentifier()] = keyBackupData
+                                ?.let {
+                                    keysBackupData.roomIdToRoomKeysBackupData
+                                            .getOrPut(roomId) { RoomKeysBackupData() }
+                                            .sessionIdToKeyBackupData[olmInboundGroupSession.sessionIdentifier()] = it
+                                }
                     } catch (e: OlmException) {
                         Timber.e(e, "OlmException")
                     }
@@ -1235,7 +1232,12 @@ internal class DefaultKeysBackupService @Inject constructor(
 
                 Timber.v("backupKeys: 4 - Sending request")
 
-                val sendingRequestCallback = object : MatrixCallback<BackupKeysResult> {
+                // Make the request
+                val version = keysBackupVersion?.version ?: return@withContext
+
+                storeSessionDataTask
+                        .configureWith(StoreSessionsDataTask.Params(version, keysBackupData)) {
+                            this.callback = object : MatrixCallback<BackupKeysResult> {
                                 override fun onSuccess(data: BackupKeysResult) {
                                     uiHandler.post {
                                         Timber.v("backupKeys: 5a - Request complete")
@@ -1295,11 +1297,6 @@ internal class DefaultKeysBackupService @Inject constructor(
                                     }
                                 }
                             }
-
-                // Make the request
-                storeSessionDataTask
-                        .configureWith(StoreSessionsDataTask.Params(keysBackupVersion!!.version, keysBackupData)) {
-                            this.callback = sendingRequestCallback
                         }
                         .executeBy(taskExecutor)
             }
@@ -1308,46 +1305,45 @@ internal class DefaultKeysBackupService @Inject constructor(
 
     @VisibleForTesting
     @WorkerThread
-    fun encryptGroupSession(olmInboundGroupSessionWrapper: OlmInboundGroupSessionWrapper2): KeyBackupData {
+    fun encryptGroupSession(olmInboundGroupSessionWrapper: OlmInboundGroupSessionWrapper2): KeyBackupData? {
         // Gather information for each key
-        val device = cryptoStore.deviceWithIdentityKey(olmInboundGroupSessionWrapper.senderKey!!)
+        val device = olmInboundGroupSessionWrapper.senderKey?.let { cryptoStore.deviceWithIdentityKey(it) }
 
         // Build the m.megolm_backup.v1.curve25519-aes-sha2 data as defined at
         // https://github.com/uhoreg/matrix-doc/blob/e2e_backup/proposals/1219-storing-megolm-keys-serverside.md#mmegolm_backupv1curve25519-aes-sha2-key-format
-        val sessionData = olmInboundGroupSessionWrapper.exportKeys()
+        val sessionData = olmInboundGroupSessionWrapper.exportKeys() ?: return null
         val sessionBackupData = mapOf(
-                "algorithm" to sessionData!!.algorithm,
+                "algorithm" to sessionData.algorithm,
                 "sender_key" to sessionData.senderKey,
                 "sender_claimed_keys" to sessionData.senderClaimedKeys,
                 "forwarding_curve25519_key_chain" to (sessionData.forwardingCurve25519KeyChain.orEmpty()),
                 "session_key" to sessionData.sessionKey)
 
-        var encryptedSessionBackupData: OlmPkMessage? = null
+        val json = MoshiProvider.providesMoshi()
+                .adapter(Map::class.java)
+                .toJson(sessionBackupData)
 
-        val moshi = MoshiProvider.providesMoshi()
+        val encryptedSessionBackupData = try {
-        val adapter = moshi.adapter(Map::class.java)
+            backupOlmPkEncryption?.encrypt(json)
-
-        try {
-            val json = adapter.toJson(sessionBackupData)
-
-            encryptedSessionBackupData = backupOlmPkEncryption?.encrypt(json)
         } catch (e: OlmException) {
             Timber.e(e, "OlmException")
+            null
         }
+                ?: return null
 
         // Build backup data for that key
         return KeyBackupData(
                 firstMessageIndex = try {
-                    olmInboundGroupSessionWrapper.olmInboundGroupSession!!.firstKnownIndex
+                    olmInboundGroupSessionWrapper.olmInboundGroupSession?.firstKnownIndex ?: 0
                 } catch (e: OlmException) {
                     Timber.e(e, "OlmException")
                     0L
                 },
-                forwardedCount = olmInboundGroupSessionWrapper.forwardingCurve25519KeyChain!!.size,
+                forwardedCount = olmInboundGroupSessionWrapper.forwardingCurve25519KeyChain.orEmpty().size,
                 isVerified = device?.isVerified == true,
 
                 sessionData = mapOf(
-                        "ciphertext" to encryptedSessionBackupData!!.mCipherText,
+                        "ciphertext" to encryptedSessionBackupData.mCipherText,
                         "mac" to encryptedSessionBackupData.mMac,
                         "ephemeral" to encryptedSessionBackupData.mEphemeralKey)
         )