Introduce ExtractMigrationDataUseCase

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/store/ExtractMigrationDataUseCase.kt

@@ -0,0 +1,126 @@
+/*
+ * Copyright (c) 2022 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.matrix.android.sdk.internal.crypto.store
+
+import io.realm.Realm
+import io.realm.kotlin.where
+import org.matrix.android.sdk.internal.crypto.store.db.model.CryptoMetadataEntity
+import org.matrix.android.sdk.internal.crypto.store.db.model.OlmInboundGroupSessionEntity
+import org.matrix.android.sdk.internal.crypto.store.db.model.OlmSessionEntity
+import org.matrix.android.sdk.internal.crypto.store.db.model.UserEntity
+import org.matrix.olm.OlmUtility
+import uniffi.olm.CrossSigningKeyExport
+import uniffi.olm.MigrationData
+import uniffi.olm.PickledAccount
+import uniffi.olm.PickledInboundGroupSession
+import uniffi.olm.PickledSession
+import java.nio.charset.Charset
+
+private val charset = Charset.forName("UTF-8")
+
+internal class ExtractMigrationDataUseCase() {
+
+    operator fun invoke(realm: Realm): MigrationData? {
+        val pickleKey = OlmUtility.getRandomKey()
+
+        val olmSessionEntities = realm.where<OlmSessionEntity>().findAll()
+        val pickledSessions = olmSessionEntities.map { it.toPickledSession(pickleKey) }
+
+        val inboundGroupSessionEntities = realm.where<OlmInboundGroupSessionEntity>().findAll()
+        val pickledInboundGroupSessions = inboundGroupSessionEntities.map { it.toPickledInboundGroupSession(pickleKey) }
+
+        val metadataEntity = realm.where<CryptoMetadataEntity>().findFirst() ?: return null
+        val masterKey = metadataEntity.xSignMasterPrivateKey
+        val userKey = metadataEntity.xSignUserPrivateKey
+        val selfSignedKey = metadataEntity.xSignSelfSignedPrivateKey
+
+        val userId = metadataEntity.userId!!
+        val deviceId = metadataEntity.deviceId!!
+        val backupVersion = metadataEntity.backupVersion
+        val backupRecoveryKey = metadataEntity.keyBackupRecoveryKey
+
+        val trackedUserEntities = realm.where<UserEntity>().findAll()
+        val trackedUserIds = trackedUserEntities.mapNotNull {
+            it.userId
+        }
+        val isOlmAccountShared = metadataEntity.deviceKeysSentToServer
+
+        val olmAccount = metadataEntity.getOlmAccount()!!
+        val pickledOlmAccount = olmAccount.pickle(pickleKey)
+        val pickledAccount = PickledAccount(
+                userId = userId,
+                deviceId = deviceId,
+                pickle = pickledOlmAccount,
+                shared = isOlmAccountShared,
+                uploadedSignedKeyCount = 50
+        )
+        return MigrationData(
+                account = pickledAccount,
+                sessions = pickledSessions,
+                inboundGroupSessions = pickledInboundGroupSessions,
+                pickleKey = String(pickleKey, charset),
+                backupVersion = backupVersion,
+                backupRecoveryKey = backupRecoveryKey,
+                crossSigning = CrossSigningKeyExport(
+                        masterKey = masterKey,
+                        selfSigningKey = selfSignedKey,
+                        userSigningKey = userKey
+                ),
+                trackedUsers = trackedUserIds
+        )
+    }
+
+    private fun OlmInboundGroupSessionEntity.toPickledInboundGroupSession(pickleKey: ByteArray): PickledInboundGroupSession {
+        val senderKey = this.senderKey ?: ""
+        val olmInboundGroupSession = getInboundGroupSession()!!
+        val pickledInboundGroupSession = olmInboundGroupSession.olmInboundGroupSession!!.pickle(pickleKey)
+        return PickledInboundGroupSession(
+                pickle = pickledInboundGroupSession,
+                senderKey = senderKey,
+                signingKey = olmInboundGroupSession.keysClaimed.orEmpty(),
+                roomId = olmInboundGroupSession.roomId!!,
+                forwardingChains = olmInboundGroupSession.forwardingCurve25519KeyChain.orEmpty(),
+                imported = true,
+                backedUp = backedUp
+        )
+    }
+
+    private fun OlmSessionEntity.toPickledSession(pickleKey: ByteArray): PickledSession {
+        val deviceKey = this.deviceKey ?: ""
+        val lastReceivedMessageTs = this.lastReceivedMessageTs
+        val olmSession = getOlmSession()!!
+        val pickledOlmSession = olmSession.pickle(pickleKey)
+        return PickledSession(
+                pickle = pickledOlmSession,
+                senderKey = deviceKey,
+                createdUsingFallbackKey = false,
+                creationTime = lastReceivedMessageTs.toString(),
+                lastUseTime = lastReceivedMessageTs.toString()
+        )
+    }
+
+    private fun Any.pickle(pickleKey: ByteArray): String {
+        return try {
+            val pickleMethod = this.javaClass.getDeclaredMethod("serialize", ByteArray::class.java, StringBuffer::class.java)
+            pickleMethod.isAccessible = true
+            val pickled = pickleMethod.invoke(this, pickleKey, StringBuffer())!!
+            String(pickled as ByteArray, charset)
+        } catch (throwable: Throwable) {
+            ""
+        }
+    }
+}