crypto: Initial support to answer to-device verification requests

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

@@ -49,6 +49,7 @@ import org.matrix.android.sdk.api.listeners.ProgressListener
 import org.matrix.android.sdk.api.session.crypto.CryptoService
 import org.matrix.android.sdk.api.session.crypto.MXCryptoError
 import org.matrix.android.sdk.api.session.crypto.keyshare.GossipingRequestListener
+import org.matrix.android.sdk.api.session.crypto.verification.VerificationService
 import org.matrix.android.sdk.api.session.events.model.Content
 import org.matrix.android.sdk.api.session.events.model.Event
 import org.matrix.android.sdk.api.session.events.model.EventType
@@ -86,7 +87,7 @@ import org.matrix.android.sdk.internal.crypto.tasks.UploadKeysTask
 import org.matrix.android.sdk.internal.crypto.tasks.SetDeviceNameTask
 import org.matrix.android.sdk.internal.crypto.tasks.SendToDeviceTask
 import org.matrix.android.sdk.internal.crypto.tasks.ClaimOneTimeKeysForUsersDeviceTask
-import org.matrix.android.sdk.internal.crypto.verification.DefaultVerificationService
+import org.matrix.android.sdk.internal.crypto.verification.RustVerificationService
 import org.matrix.android.sdk.internal.di.DeviceId
 import org.matrix.android.sdk.internal.di.MoshiProvider
 import org.matrix.android.sdk.internal.di.SessionFilesDirectory
@@ -131,9 +132,6 @@ internal class DefaultCryptoService @Inject constructor(
         private val mxCryptoConfig: MXCryptoConfig,
         // The key backup service.
         private val keysBackupService: DefaultKeysBackupService,
-        // The verification service.
-        private val verificationService: DefaultVerificationService,
-
         private val crossSigningService: DefaultCrossSigningService,
         // Actions
         private val warnOnUnknownDevicesRepository: WarnOnUnknownDeviceRepository,
@@ -156,6 +154,9 @@ internal class DefaultCryptoService @Inject constructor(
     private val isStarting = AtomicBoolean(false)
     private val isStarted = AtomicBoolean(false)
     private var olmMachine: OlmMachine? = null
+    // The verification service.
+    private var verificationService: RustVerificationService? = null
+
     private val deviceObserver: DeviceUpdateObserver = DeviceUpdateObserver()
 
     // Locks for some of our operations
@@ -179,6 +180,7 @@ internal class DefaultCryptoService @Inject constructor(
             EventType.STATE_ROOM_ENCRYPTION         -> onRoomEncryptionEvent(roomId, event)
             EventType.STATE_ROOM_MEMBER             -> onRoomMembershipEvent(roomId, event)
             EventType.STATE_ROOM_HISTORY_VISIBILITY -> onRoomHistoryVisibilityEvent(roomId, event)
+            else -> this.verificationService?.onEvent(event)
         }
     }
 
@@ -315,7 +317,10 @@ internal class DefaultCryptoService @Inject constructor(
 
         try {
             setRustLogger()
-            this.olmMachine = OlmMachine(userId, deviceId!!, dataDir, deviceObserver)
+            val machine = OlmMachine(userId, deviceId!!, dataDir, deviceObserver)
+            this.olmMachine = machine
+            this.verificationService =
+            RustVerificationService(this.taskExecutor, machine, this.sendToDeviceTask)
             Timber.v(
                 "## CRYPTO | Successfully started up an Olm machine for " +
                 "${userId}, ${deviceId}, identity keys: ${this.olmMachine?.identityKeys()}")
@@ -359,7 +364,32 @@ internal class DefaultCryptoService @Inject constructor(
     /**
      * @return the VerificationService
      */
-    override fun verificationService() = verificationService
+    override fun verificationService(): VerificationService {
+        // TODO yet another problem because the CryptoService is started in the
+        // sync loop
+        //
+        // The `KeyRequestHandler` and `IncomingVerificationHandler` want to add
+        // listeners to the verification service, they are initialized in the
+        // `ActiveSessionHolder` class in the `setActiveSession()` method. In
+        // the `setActiveSession()` method we call the `start()` method of the
+        // handlers without first calling the `start()` method of the
+        // `DefaultCrytpoService`.
+        //
+        // The start method of the crypto service isn't part of the
+        // `CryptoService` interface so it currently can't be called there. I'm
+        // inclined to believe that it should be, and that it should be
+        // initialized before anything else tries to do something with it.
+        //
+        // Let's initialize here as a workaround until we figure out if the
+        // above conclusion is correct.
+        if (verificationService == null) {
+            runBlocking {
+                internalStart()
+            }
+        }
+
+        return verificationService!!
+    }
 
     override fun crossSigningService() = crossSigningService
 
@@ -677,6 +707,8 @@ internal class DefaultCryptoService @Inject constructor(
                         val sessionId = content.sessionId
 
                         notifyRoomKeyReceival(roomId, sessionId)
+                    } else {
+                        this.verificationService?.onEvent(event)
                     }
                 }
             }

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

@@ -26,33 +26,44 @@ import kotlinx.coroutines.runBlocking
 import kotlinx.coroutines.withContext
 import org.matrix.android.sdk.api.listeners.ProgressListener
 import org.matrix.android.sdk.api.session.crypto.MXCryptoError
+import org.matrix.android.sdk.api.session.crypto.verification.CancelCode
+import org.matrix.android.sdk.api.session.crypto.verification.EmojiRepresentation
+import org.matrix.android.sdk.api.session.crypto.verification.PendingVerificationRequest
+import org.matrix.android.sdk.api.session.crypto.verification.ValidVerificationInfoReady
+import org.matrix.android.sdk.api.session.crypto.verification.ValidVerificationInfoRequest
+import org.matrix.android.sdk.api.session.crypto.verification.VerificationMethod
 import org.matrix.android.sdk.api.session.events.model.Content
 import org.matrix.android.sdk.api.session.events.model.Event
-import org.matrix.android.sdk.api.session.crypto.verification.EmojiRepresentation
 import org.matrix.android.sdk.api.util.JsonDict
 import org.matrix.android.sdk.internal.crypto.crosssigning.DeviceTrustLevel
 import org.matrix.android.sdk.internal.crypto.model.CryptoDeviceInfo
 import org.matrix.android.sdk.internal.crypto.model.ImportRoomKeysResult
 import org.matrix.android.sdk.internal.crypto.model.MXUsersDevicesMap
 import org.matrix.android.sdk.internal.crypto.model.rest.UnsignedDeviceInfo
+import org.matrix.android.sdk.internal.crypto.model.rest.VERIFICATION_METHOD_QR_CODE_SCAN
+import org.matrix.android.sdk.internal.crypto.model.rest.VERIFICATION_METHOD_QR_CODE_SHOW
+import org.matrix.android.sdk.internal.crypto.model.rest.VERIFICATION_METHOD_RECIPROCATE
+import org.matrix.android.sdk.internal.crypto.model.rest.VERIFICATION_METHOD_SAS
 import org.matrix.android.sdk.internal.crypto.verification.getEmojiForCode
 import org.matrix.android.sdk.internal.di.MoshiProvider
 import org.matrix.android.sdk.internal.session.sync.model.DeviceListResponse
 import org.matrix.android.sdk.internal.session.sync.model.DeviceOneTimeKeysCountSyncResponse
 import org.matrix.android.sdk.internal.session.sync.model.ToDeviceSyncResponse
 import timber.log.Timber
+import uniffi.olm.CancelCode as RustCancelCode
 import uniffi.olm.CryptoStoreErrorException
 import uniffi.olm.DecryptionErrorException
-import uniffi.olm.Sas as InnerSas
-import uniffi.olm.OutgoingVerificationRequest
 import uniffi.olm.Device
 import uniffi.olm.DeviceLists
 import uniffi.olm.KeyRequestPair
 import uniffi.olm.Logger
 import uniffi.olm.OlmMachine as InnerMachine
+import uniffi.olm.OutgoingVerificationRequest
 import uniffi.olm.ProgressListener as RustProgressListener
 import uniffi.olm.Request
 import uniffi.olm.RequestType
+import uniffi.olm.Sas as InnerSas
+import uniffi.olm.VerificationRequest as InnerRequest
 import uniffi.olm.setLogger
 
 class CryptoLogger : Logger {
@@ -89,13 +100,9 @@ fun setRustLogger() {
     setLogger(CryptoLogger() as Logger)
 }
 
-/**
+/** Convert a Rust Device into a Kotlin CryptoDeviceInfo */
- * Convert a Rust Device into a Kotlin CryptoDeviceInfo
- */
 private fun toCryptoDeviceInfo(device: Device): CryptoDeviceInfo {
-    val keys = device.keys.map { (keyId, key) ->
+    val keys = device.keys.map { (keyId, key) -> "$keyId:$device.deviceId" to key }.toMap()
-        "$keyId:$device.deviceId" to key
-    }.toMap()
 
     return CryptoDeviceInfo(
             device.deviceId,
@@ -110,8 +117,7 @@ private fun toCryptoDeviceInfo(device: Device): CryptoDeviceInfo {
             DeviceTrustLevel(crossSigningVerified = false, locallyVerified = false),
             device.isBlocked,
             // TODO
-            null
+            null)
-        )
 }
 
 internal class DeviceUpdateObserver {
@@ -126,6 +132,150 @@ internal class DeviceUpdateObserver {
     }
 }
 
+internal class VerificationRequest(
+        private val machine: InnerMachine,
+        private var inner: InnerRequest
+) {
+    private fun refreshData() {
+        val request = this.machine.getVerificationRequest(this.inner.otherUserId, this.inner.flowId)
+
+        if (request != null) {
+            this.inner = request
+        }
+
+        return
+    }
+
+    fun accept_with_methods(methods: List<VerificationMethod>): OutgoingVerificationRequest? {
+        val stringMethods: MutableList<String> =
+                methods.map {
+                    when (it) {
+                        VerificationMethod.QR_CODE_SCAN -> VERIFICATION_METHOD_QR_CODE_SCAN
+                        VerificationMethod.QR_CODE_SHOW -> VERIFICATION_METHOD_QR_CODE_SHOW
+                        VerificationMethod.SAS -> VERIFICATION_METHOD_SAS
+                    }
+                }.toMutableList()
+
+        if (stringMethods.contains(VERIFICATION_METHOD_QR_CODE_SHOW) ||
+                stringMethods.contains(VERIFICATION_METHOD_QR_CODE_SCAN)) {
+            stringMethods.add(VERIFICATION_METHOD_RECIPROCATE)
+        }
+
+        return this.machine.acceptVerificationRequest(
+                this.inner.otherUserId, this.inner.flowId, stringMethods)
+    }
+
+    fun isCanceled(): Boolean {
+        refreshData()
+        return this.inner.isCancelled
+    }
+
+    fun isDone(): Boolean {
+        refreshData()
+        return this.inner.isDone
+    }
+
+    fun isReady(): Boolean {
+        refreshData()
+        return this.inner.isReady
+    }
+
+    fun toPendingVerificationRequest(): PendingVerificationRequest {
+        refreshData()
+        val code = this.inner.cancelCode
+
+        val cancelCode =
+                if (code != null) {
+                    toCancelCode(code)
+                } else {
+                    null
+                }
+
+        val ourMethods = this.inner.ourMethods
+        val theirMethods = this.inner.theirMethods
+        val otherDeviceId = this.inner.otherDeviceId
+
+        var requestInfo: ValidVerificationInfoRequest? = null
+        var readyInfo: ValidVerificationInfoReady? = null
+
+        if (this.inner.weStarted && ourMethods != null) {
+            requestInfo =
+                    ValidVerificationInfoRequest(
+                            this.inner.flowId,
+                            this.machine.deviceId(),
+                            ourMethods,
+                            null,
+                    )
+        } else if (!this.inner.weStarted && ourMethods != null) {
+            readyInfo =
+                    ValidVerificationInfoReady(
+                            this.inner.flowId,
+                            this.machine.deviceId(),
+                            ourMethods,
+                    )
+        }
+
+        if (this.inner.weStarted && theirMethods != null && otherDeviceId != null) {
+            readyInfo =
+                    ValidVerificationInfoReady(
+                            this.inner.flowId,
+                            otherDeviceId,
+                            theirMethods,
+                    )
+        } else if (!this.inner.weStarted && theirMethods != null && otherDeviceId != null) {
+            requestInfo =
+                    ValidVerificationInfoRequest(
+                            this.inner.flowId,
+                            otherDeviceId,
+                            theirMethods,
+                            System.currentTimeMillis(),
+                    )
+        }
+
+        return PendingVerificationRequest(
+                // Creation time
+                System.currentTimeMillis(),
+                // Who initiated the request
+                !this.inner.weStarted,
+                // Local echo id, what to do here?
+                this.inner.flowId,
+                // other user
+                this.inner.otherUserId,
+                // room id
+                this.inner.roomId,
+                // transaction id
+                this.inner.flowId,
+                // val requestInfo: ValidVerificationInfoRequest? = null,
+                requestInfo,
+                // val readyInfo: ValidVerificationInfoReady? = null,
+                readyInfo,
+                // cancel code if there is one
+                cancelCode,
+                // are we done/successful
+                this.inner.isDone,
+                // did another device answer the request
+                this.inner.isPassive,
+                // devices that should receive the events we send out
+                null,
+        )
+    }
+}
+
+private fun toCancelCode(cancelCode: RustCancelCode): CancelCode {
+    return when (cancelCode) {
+        RustCancelCode.USER -> CancelCode.User
+        RustCancelCode.TIMEOUT -> CancelCode.Timeout
+        RustCancelCode.UNKNOWN_TRANSACTION -> CancelCode.UnknownTransaction
+        RustCancelCode.UNKNOWN_METHOD -> CancelCode.UnknownMethod
+        RustCancelCode.UNEXPECTED_MESSAGE -> CancelCode.UnexpectedMessage
+        RustCancelCode.KEY_MISMATCH -> CancelCode.MismatchedKeys
+        RustCancelCode.USER_MISMATCH -> CancelCode.MismatchedKeys
+        RustCancelCode.INVALID_MESSAGE -> CancelCode.InvalidMessage
+        // TODO why don't the ruma codes match what's in EA?
+        RustCancelCode.ACCEPTED -> CancelCode.User
+    }
+}
+
 internal class Sas(private val machine: InnerMachine, private var inner: InnerSas) {
     private fun refreshData() {
         val sas = this.machine.getVerification(this.inner.flowId)
@@ -139,7 +289,7 @@ internal class Sas(private val machine: InnerMachine, private var inner: InnerSa
 
     fun isCanceled(): Boolean {
         refreshData()
-        return this.inner.isCanceled
+        return this.inner.isCancelled
     }
 
     fun isDone(): Boolean {
@@ -162,9 +312,8 @@ internal class Sas(private val machine: InnerMachine, private var inner: InnerSa
     }
 
     @Throws(CryptoStoreErrorException::class)
-    suspend fun confirm(): OutgoingVerificationRequest? = withContext(Dispatchers.IO) {
+    suspend fun confirm(): OutgoingVerificationRequest? =
-        machine.confirmVerification(inner.flowId)
+            withContext(Dispatchers.IO) { machine.confirmVerification(inner.flowId) }
-    }
 
     fun cancel(): OutgoingVerificationRequest? {
         return this.machine.cancelVerification(inner.flowId)
@@ -185,27 +334,26 @@ internal class Sas(private val machine: InnerMachine, private var inner: InnerSa
     }
 }
 
-internal class OlmMachine(user_id: String, device_id: String, path: File, deviceObserver: DeviceUpdateObserver) {
+internal class OlmMachine(
+        user_id: String,
+        device_id: String,
+        path: File,
+        deviceObserver: DeviceUpdateObserver
+) {
     private val inner: InnerMachine = InnerMachine(user_id, device_id, path.toString())
     private val deviceUpdateObserver = deviceObserver
 
-    /**
+    /** Get our own user ID. */
-     * Get our own user ID.
-     */
     fun userId(): String {
         return this.inner.userId()
     }
 
-    /**
+    /** Get our own device ID. */
-     * Get our own device ID.
-     */
     fun deviceId(): String {
         return this.inner.deviceId()
     }
 
-    /**
+    /** Get our own public identity keys ID. */
-     * Get our own public identity keys ID.
-     */
     fun identityKeys(): Map<String, String> {
         return this.inner.identityKeys()
     }
@@ -213,9 +361,7 @@ internal class OlmMachine(user_id: String, device_id: String, path: File, device
     fun ownDevice(): CryptoDeviceInfo {
         val deviceId = this.deviceId()
 
-        val keys = this.identityKeys().map { (keyId, key) ->
+        val keys = this.identityKeys().map { (keyId, key) -> "$keyId:$deviceId" to key }.toMap()
-            "$keyId:$deviceId" to key
-        }.toMap()
 
         return CryptoDeviceInfo(
                 this.deviceId(),
@@ -227,22 +373,19 @@ internal class OlmMachine(user_id: String, device_id: String, path: File, device
                 UnsignedDeviceInfo(),
                 DeviceTrustLevel(crossSigningVerified = false, locallyVerified = true),
                 false,
-            null
+                null)
-        )
     }
 
     /**
      * Get the list of outgoing requests that need to be sent to the homeserver.
      *
-     * After the request was sent out and a successful response was received
+     * After the request was sent out and a successful response was received the response body
-     * the response body should be passed back to the state machine using the
+     * should be passed back to the state machine using the markRequestAsSent() method.
-     * markRequestAsSent() method.
      *
      * @return the list of requests that needs to be sent to the homeserver
      */
-    suspend fun outgoingRequests(): List<Request> = withContext(Dispatchers.IO) {
+    suspend fun outgoingRequests(): List<Request> =
-        inner.outgoingRequests()
+            withContext(Dispatchers.IO) { inner.outgoingRequests() }
-    }
 
     /**
      * Mark a request that was sent to the server as sent.
@@ -258,7 +401,8 @@ internal class OlmMachine(user_id: String, device_id: String, path: File, device
             requestId: String,
             requestType: RequestType,
             responseBody: String
-    ) = withContext(Dispatchers.IO) {
+    ) =
+            withContext(Dispatchers.IO) {
                 inner.markRequestAsSent(requestId, requestType, responseBody)
 
                 if (requestType == RequestType.KEYS_QUERY) {
@@ -267,17 +411,15 @@ internal class OlmMachine(user_id: String, device_id: String, path: File, device
             }
 
     /**
-     * Let the state machine know about E2EE related sync changes that we
+     * Let the state machine know about E2EE related sync changes that we received from the server.
-     * received from the server.
      *
-     * This needs to be called after every sync, ideally before processing
+     * This needs to be called after every sync, ideally before processing any other sync changes.
-     * any other sync changes.
      *
-     * @param toDevice A serialized array of to-device events we received in the
+     * @param toDevice A serialized array of to-device events we received in the current sync
-     * current sync resposne.
+     * resposne.
      *
-     * @param deviceChanges The list of devices that have changed in some way
+     * @param deviceChanges The list of devices that have changed in some way since the previous
-     * since the previous sync.
+     * sync.
      *
      * @param keyCounts The map of uploaded one-time key types and counts.
      */
@@ -286,104 +428,97 @@ internal class OlmMachine(user_id: String, device_id: String, path: File, device
             toDevice: ToDeviceSyncResponse?,
             deviceChanges: DeviceListResponse?,
             keyCounts: DeviceOneTimeKeysCountSyncResponse?
-    ): ToDeviceSyncResponse = withContext(Dispatchers.IO) {
+    ): ToDeviceSyncResponse =
+            withContext(Dispatchers.IO) {
                 val counts: MutableMap<String, Int> = mutableMapOf()
 
                 if (keyCounts?.signedCurve25519 != null) {
                     counts["signed_curve25519"] = keyCounts.signedCurve25519
                 }
 
-            val devices = DeviceLists(deviceChanges?.changed ?: listOf(), deviceChanges?.left ?: listOf())
+                val devices =
-            val adapter = MoshiProvider.providesMoshi().adapter(ToDeviceSyncResponse::class.java)
+                        DeviceLists(
+                                deviceChanges?.changed ?: listOf(), deviceChanges?.left ?: listOf())
+                val adapter =
+                        MoshiProvider.providesMoshi().adapter(ToDeviceSyncResponse::class.java)
                 val events = adapter.toJson(toDevice ?: ToDeviceSyncResponse())!!
 
                 adapter.fromJson(inner.receiveSyncChanges(events, devices, counts))!!
             }
 
     /**
-     * Mark the given list of users to be tracked, triggering a key query request
+     * Mark the given list of users to be tracked, triggering a key query request for them.
-     * for them.
      *
-     * *Note*: Only users that aren't already tracked will be considered for an
+     * *Note*: Only users that aren't already tracked will be considered for an update. It's safe to
-     * update. It's safe to call this with already tracked users, it won't
+     * call this with already tracked users, it won't result in excessive keys query requests.
-     * result in excessive keys query requests.
      *
      * @param users The users that should be queued up for a key query.
      */
-    suspend fun updateTrackedUsers(users: List<String>) = withContext(Dispatchers.IO) {
+    suspend fun updateTrackedUsers(users: List<String>) =
-        inner.updateTrackedUsers(users)
+            withContext(Dispatchers.IO) { inner.updateTrackedUsers(users) }
-    }
 
     /**
-     * Generate one-time key claiming requests for all the users we are missing
+     * Generate one-time key claiming requests for all the users we are missing sessions for.
-     * sessions for.
      *
-     * After the request was sent out and a successful response was received
+     * After the request was sent out and a successful response was received the response body
-     * the response body should be passed back to the state machine using the
+     * should be passed back to the state machine using the markRequestAsSent() method.
-     * markRequestAsSent() method.
      *
-     * This method should be called every time before a call to
+     * This method should be called every time before a call to shareRoomKey() is made.
-     * shareRoomKey() is made.
      *
-     * @param users The list of users for which we would like to establish 1:1
+     * @param users The list of users for which we would like to establish 1:1 Olm sessions for.
-     * Olm sessions for.
      *
      * @return A keys claim request that needs to be sent out to the server.
      */
     @Throws(CryptoStoreErrorException::class)
-    suspend fun getMissingSessions(users: List<String>): Request? = withContext(Dispatchers.IO) {
+    suspend fun getMissingSessions(users: List<String>): Request? =
-        inner.getMissingSessions(users)
+            withContext(Dispatchers.IO) { inner.getMissingSessions(users) }
-    }
 
     /**
      * Share a room key with the given list of users for the given room.
      *
-     * After the request was sent out and a successful response was received
+     * After the request was sent out and a successful response was received the response body
-     * the response body should be passed back to the state machine using the
+     * should be passed back to the state machine using the markRequestAsSent() method.
-     * markRequestAsSent() method.
      *
-     * This method should be called every time before a call to
+     * This method should be called every time before a call to `encrypt()` with the given `room_id`
-     * `encrypt()` with the given `room_id` is made.
+     * is made.
      *
-     * @param roomId The unique id of the room, note that this doesn't strictly
+     * @param roomId The unique id of the room, note that this doesn't strictly need to be a Matrix
-     * need to be a Matrix room, it just needs to be an unique identifier for
+     * room, it just needs to be an unique identifier for the group that will participate in the
-     * the group that will participate in the conversation.
+     * conversation.
      *
-     * @param users The list of users which are considered to be members of the
+     * @param users The list of users which are considered to be members of the room and should
-     * room and should receive the room key.
+     * receive the room key.
      *
      * @return The list of requests that need to be sent out.
      */
     @Throws(CryptoStoreErrorException::class)
-    suspend fun shareRoomKey(roomId: String, users: List<String>): List<Request> = withContext(Dispatchers.IO) {
+    suspend fun shareRoomKey(roomId: String, users: List<String>): List<Request> =
-        inner.shareRoomKey(roomId, users)
+            withContext(Dispatchers.IO) { inner.shareRoomKey(roomId, users) }
-    }
 
     /**
-     * Encrypt the given event with the given type and content for the given
+     * Encrypt the given event with the given type and content for the given room.
-     * room.
      *
-     * **Note**: A room key needs to be shared with the group of users that are
+     * **Note**: A room key needs to be shared with the group of users that are members in the given
-     * members in the given room. If this is not done this method will panic.
+     * room. If this is not done this method will panic.
      *
-     * The usual flow to encrypt an evnet using this state machine is as
+     * The usual flow to encrypt an evnet using this state machine is as follows:
-     * follows:
      *
      * 1. Get the one-time key claim request to establish 1:1 Olm sessions for
+     * ```
      *    the room members of the room we wish to participate in. This is done
      *    using the [`get_missing_sessions()`](#method.get_missing_sessions)
      *    method. This method call should be locked per call.
-     *
+     * ```
      * 2. Share a room key with all the room members using the shareRoomKey().
+     * ```
      *    This method call should be locked per room.
-     *
+     * ```
      * 3. Encrypt the event using this method.
      *
      * 4. Send the encrypted event to the server.
      *
-     * After the room key is shared steps 1 and 2 will become noops, unless
+     * After the room key is shared steps 1 and 2 will become noops, unless there's some changes in
-     * there's some changes in the room membership or in the list of devices a
+     * the room membership or in the list of devices a member has.
-     * member has.
      *
      * @param roomId the ID of the room where the encrypted event will be sent to
      *
@@ -394,7 +529,8 @@ internal class OlmMachine(user_id: String, device_id: String, path: File, device
      * @return The encrypted version of the content
      */
     @Throws(CryptoStoreErrorException::class)
-    suspend fun encrypt(roomId: String, eventType: String, content: Content): Content = withContext(Dispatchers.IO) {
+    suspend fun encrypt(roomId: String, eventType: String, content: Content): Content =
+            withContext(Dispatchers.IO) {
                 val adapter = MoshiProvider.providesMoshi().adapter<Content>(Map::class.java)
                 val contentString = adapter.toJson(content)
                 val encrypted = inner.encrypt(roomId, eventType, contentString)
@@ -411,41 +547,45 @@ internal class OlmMachine(user_id: String, device_id: String, path: File, device
      * @return the decrypted version of the event.
      */
     @Throws(MXCryptoError::class)
-    suspend fun decryptRoomEvent(event: Event): MXEventDecryptionResult = withContext(Dispatchers.IO) {
+    suspend fun decryptRoomEvent(event: Event): MXEventDecryptionResult =
+            withContext(Dispatchers.IO) {
                 val adapter = MoshiProvider.providesMoshi().adapter(Event::class.java)
                 val serializedEvent = adapter.toJson(event)
 
                 try {
                     val decrypted = inner.decryptRoomEvent(serializedEvent, event.roomId!!)
 
-            val deserializationAdapter = MoshiProvider.providesMoshi().adapter<JsonDict>(Map::class.java)
+                    val deserializationAdapter =
+                            MoshiProvider.providesMoshi().adapter<JsonDict>(Map::class.java)
                     val clearEvent = deserializationAdapter.fromJson(decrypted.clearEvent)!!
 
                     MXEventDecryptionResult(
                             clearEvent,
                             decrypted.senderCurve25519Key,
                             decrypted.claimedEd25519Key,
-                decrypted.forwardingCurve25519Chain
+                            decrypted.forwardingCurve25519Chain)
-            )
                 } catch (throwable: Throwable) {
-            val reason = String.format(MXCryptoError.UNABLE_TO_DECRYPT_REASON, throwable.message, "m.megolm.v1.aes-sha2")
+                    val reason =
+                            String.format(
+                                    MXCryptoError.UNABLE_TO_DECRYPT_REASON,
+                                    throwable.message,
+                                    "m.megolm.v1.aes-sha2")
                     throw MXCryptoError.Base(MXCryptoError.ErrorType.UNABLE_TO_DECRYPT, reason)
                 }
             }
 
     /**
-     * Request the room key that was used to encrypt the given undecrypted
+     * Request the room key that was used to encrypt the given undecrypted event.
-     * event.
      *
-     * @param event The that we're not able to decrypt and want to request a
+     * @param event The that we're not able to decrypt and want to request a room key for.
-     * room key for.
      *
-     * @return a key request pair, consisting of an optional key request
+     * @return a key request pair, consisting of an optional key request cancellation and the key
-     * cancellation and the key request itself. The cancellation *must* be sent
+     * request itself. The cancellation *must* be sent out before the request, otherwise devices
-     * out before the request, otherwise devices will ignore the key request.
+     * will ignore the key request.
      */
     @Throws(DecryptionErrorException::class)
-    suspend fun requestRoomKey(event: Event): KeyRequestPair = withContext(Dispatchers.IO) {
+    suspend fun requestRoomKey(event: Event): KeyRequestPair =
+            withContext(Dispatchers.IO) {
                 val adapter = MoshiProvider.providesMoshi().adapter(Event::class.java)
                 val serializedEvent = adapter.toJson(event)
 
@@ -455,18 +595,16 @@ internal class OlmMachine(user_id: String, device_id: String, path: File, device
     /**
      * Export all of our room keys.
      *
-     * @param passphrase The passphrase that should be used to encrypt the key
+     * @param passphrase The passphrase that should be used to encrypt the key export.
-     * export.
      *
-     * @param rounds The number of rounds that should be used when expanding the
+     * @param rounds The number of rounds that should be used when expanding the passphrase into an
-     * passphrase into an key.
+     * key.
      *
      * @return the encrypted key export as a bytearray.
      */
     @Throws(CryptoStoreErrorException::class)
-    suspend fun exportKeys(passphrase: String, rounds: Int): ByteArray = withContext(Dispatchers.IO) {
+    suspend fun exportKeys(passphrase: String, rounds: Int): ByteArray =
-        inner.exportKeys(passphrase, rounds).toByteArray()
+            withContext(Dispatchers.IO) { inner.exportKeys(passphrase, rounds).toByteArray() }
-    }
 
     /**
      * Import room keys from the given serialized key export.
@@ -475,11 +613,15 @@ internal class OlmMachine(user_id: String, device_id: String, path: File, device
      *
      * @param passphrase The passphrase that was used to encrypt the key export.
      *
-     * @param listener A callback that can be used to introspect the
+     * @param listener A callback that can be used to introspect the progress of the key import.
-     * progress of the key import.
      */
     @Throws(CryptoStoreErrorException::class)
-    suspend fun importKeys(keys: ByteArray, passphrase: String, listener: ProgressListener?): ImportRoomKeysResult = withContext(Dispatchers.IO) {
+    suspend fun importKeys(
+            keys: ByteArray,
+            passphrase: String,
+            listener: ProgressListener?
+    ): ImportRoomKeysResult =
+            withContext(Dispatchers.IO) {
                 val decodedKeys = String(keys, Charset.defaultCharset())
 
                 val rustListener = CryptoProgressListener(listener)
@@ -499,7 +641,8 @@ internal class OlmMachine(user_id: String, device_id: String, path: File, device
      * @return The Device if it found one.
      */
     @Throws(CryptoStoreErrorException::class)
-    suspend fun getDevice(userId: String, deviceId: String): CryptoDeviceInfo? = withContext(Dispatchers.IO) {
+    suspend fun getDevice(userId: String, deviceId: String): CryptoDeviceInfo? =
+            withContext(Dispatchers.IO) {
                 // Our own device isn't part of our store on the rust side, return it
                 // using our ownDevice method
                 if (userId == userId() && deviceId == deviceId()) {
@@ -561,9 +704,7 @@ internal class OlmMachine(user_id: String, device_id: String, path: File, device
         return plainDevices
     }
 
-    /**
+    /** Update all of our live device listeners. */
-     * Update all of our live device listeners.
-     */
     private suspend fun updateLiveDevices() {
         for ((liveDevice, users) in deviceUpdateObserver.listeners) {
             val devices = getUserDevices(users)
@@ -574,8 +715,8 @@ internal class OlmMachine(user_id: String, device_id: String, path: File, device
     /**
      * Get all the devices of multiple users as a live version.
      *
-     * The live version will update the list of devices if some of the data
+     * The live version will update the list of devices if some of the data changes, or if new
-     * changes, or if new devices arrive for a certain user.
+     * devices arrive for a certain user.
      *
      * @param userIds The ids of the device owners.
      *
@@ -589,17 +730,29 @@ internal class OlmMachine(user_id: String, device_id: String, path: File, device
         return devices
     }
 
-    /**
+    /** Discard the currently active room key for the given room if there is one. */
-     * Discard the currently active room key for the given room if there is one.
-     */
     @Throws(CryptoStoreErrorException::class)
     fun discardRoomKey(roomId: String) {
         runBlocking { inner.discardRoomKey(roomId) }
     }
 
-    /**
+    fun getVerificationRequests(userId: String): List<VerificationRequest> {
-     * Get an active verification
+        return this.inner.getVerificationRequests(userId).map {
-     */
+            VerificationRequest(this.inner, it)
+        }
+    }
+
+    fun getVerificationRequest(userId: String, flowId: String): VerificationRequest? {
+        val request = this.inner.getVerificationRequest(userId, flowId)
+
+        return if (request == null) {
+            null
+        } else {
+            VerificationRequest(this.inner, request)
+        }
+    }
+
+    /** Get an active verification */
     fun getVerification(flowId: String): Sas? {
         val sas = this.inner.getVerification(flowId)
 

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/RustVerificationService.kt

@@ -0,0 +1,326 @@
+/*
+ * Copyright 2020 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.verification
+
+import android.os.Handler
+import android.os.Looper
+import javax.inject.Inject
+import kotlin.collections.set
+import kotlinx.coroutines.runBlocking
+import org.matrix.android.sdk.api.session.crypto.verification.PendingVerificationRequest
+import org.matrix.android.sdk.api.session.crypto.verification.VerificationMethod
+import org.matrix.android.sdk.api.session.crypto.verification.VerificationService
+import org.matrix.android.sdk.api.session.crypto.verification.VerificationTransaction
+import org.matrix.android.sdk.api.session.events.model.Event
+import org.matrix.android.sdk.api.session.events.model.EventType
+import org.matrix.android.sdk.api.session.events.model.toModel
+import org.matrix.android.sdk.api.session.room.model.message.MessageType
+import org.matrix.android.sdk.internal.crypto.OlmMachine
+import org.matrix.android.sdk.internal.crypto.model.MXUsersDevicesMap
+import org.matrix.android.sdk.internal.crypto.model.rest.KeyVerificationRequest
+import org.matrix.android.sdk.internal.crypto.tasks.SendToDeviceTask
+import org.matrix.android.sdk.internal.di.MoshiProvider
+import org.matrix.android.sdk.internal.session.SessionScope
+import org.matrix.android.sdk.internal.task.TaskExecutor
+import timber.log.Timber
+import uniffi.olm.OutgoingVerificationRequest
+
+@SessionScope
+internal class RustVerificationService
+@Inject
+constructor(
+        private val taskExecutor: TaskExecutor,
+        private val olmMachine: OlmMachine,
+        private val sendToDeviceTask: SendToDeviceTask,
+) : DefaultVerificationTransaction.Listener, VerificationService {
+
+    private val uiHandler = Handler(Looper.getMainLooper())
+    private var listeners = ArrayList<VerificationService.Listener>()
+
+    override fun addListener(listener: VerificationService.Listener) {
+        uiHandler.post {
+            if (!listeners.contains(listener)) {
+                listeners.add(listener)
+            }
+        }
+    }
+
+    override fun removeListener(listener: VerificationService.Listener) {
+        uiHandler.post { listeners.remove(listener) }
+    }
+
+    private fun dispatchTxAdded(tx: VerificationTransaction) {
+        uiHandler.post {
+            listeners.forEach {
+                try {
+                    it.transactionCreated(tx)
+                } catch (e: Throwable) {
+                    Timber.e(e, "## Error while notifying listeners")
+                }
+            }
+        }
+    }
+
+    private fun dispatchTxUpdated(tx: VerificationTransaction) {
+        uiHandler.post {
+            listeners.forEach {
+                try {
+                    it.transactionUpdated(tx)
+                } catch (e: Throwable) {
+                    Timber.e(e, "## Error while notifying listeners")
+                }
+            }
+        }
+    }
+
+    private fun dispatchRequestAdded(tx: PendingVerificationRequest) {
+        Timber.v("## SAS dispatchRequestAdded txId:${tx.transactionId} ${tx}")
+        uiHandler.post {
+            listeners.forEach {
+                try {
+                    it.verificationRequestCreated(tx)
+                } catch (e: Throwable) {
+                    Timber.e(e, "## Error while notifying listeners")
+                }
+            }
+        }
+    }
+
+    private fun dispatchRequestUpdated(tx: PendingVerificationRequest) {
+        uiHandler.post {
+            listeners.forEach {
+                try {
+                    it.verificationRequestUpdated(tx)
+                } catch (e: Throwable) {
+                    Timber.e(e, "## Error while notifying listeners")
+                }
+            }
+        }
+    }
+
+    override fun markedLocallyAsManuallyVerified(userId: String, deviceID: String) {
+        TODO()
+        // setDeviceVerificationAction.handle(DeviceTrustLevel(false, true),
+        //         userId,
+        //         deviceID)
+
+        // listeners.forEach {
+        //     try {
+        //         it.markedAsManuallyVerified(userId, deviceID)
+        //     } catch (e: Throwable) {
+        //         Timber.e(e, "## Error while notifying listeners")
+        //     }
+        // }
+    }
+
+    suspend fun onEvent(event: Event) {
+        when (event.getClearType()) {
+            EventType.KEY_VERIFICATION_START -> {}
+            EventType.KEY_VERIFICATION_CANCEL -> {}
+            EventType.KEY_VERIFICATION_ACCEPT -> {}
+            EventType.KEY_VERIFICATION_KEY -> {}
+            EventType.KEY_VERIFICATION_MAC -> {}
+            EventType.KEY_VERIFICATION_READY -> {}
+            EventType.KEY_VERIFICATION_DONE -> {}
+            MessageType.MSGTYPE_VERIFICATION_REQUEST -> {
+                onRequestReceived(event)
+            }
+            else -> {
+                // ignore
+            }
+        }
+        event == event
+        // TODO get the sender and flow id out of the event and depending on the
+        // event type either get the verification request or verification and
+        // dispatch updates here
+    }
+
+    private fun onRequestReceived(event: Event) {
+        val content = event.getClearContent().toModel<KeyVerificationRequest>() ?: return
+        val flowId = content.transactionId
+        val sender = event.senderId ?: return
+
+        val request = this.getExistingVerificationRequest(sender, flowId) ?: return
+
+        dispatchRequestAdded(request)
+    }
+
+    override fun onPotentiallyInterestingEventRoomFailToDecrypt(event: Event) {
+        // TODO This should be handled inside the rust-sdk decryption method
+    }
+
+    // TODO All this methods should be delegated to a TransactionStore
+    override fun getExistingTransaction(
+            otherUserId: String,
+            tid: String
+    ): VerificationTransaction? {
+        return null
+    }
+
+    override fun getExistingVerificationRequests(
+            otherUserId: String
+    ): List<PendingVerificationRequest> {
+        return this.olmMachine.getVerificationRequests(otherUserId).map {
+            it.toPendingVerificationRequest()
+        }
+    }
+
+    override fun getExistingVerificationRequest(
+            otherUserId: String,
+            tid: String?
+    ): PendingVerificationRequest? {
+        return if (tid != null) {
+            val request = this.olmMachine.getVerificationRequest(otherUserId, tid)
+
+            if (request != null) {
+                request.toPendingVerificationRequest()
+            } else {
+                null
+            }
+        } else {
+            null
+        }
+    }
+
+    override fun getExistingVerificationRequestInRoom(
+            roomId: String,
+            tid: String?
+    ): PendingVerificationRequest? {
+        TODO()
+    }
+
+    override fun beginKeyVerification(
+            method: VerificationMethod,
+            otherUserId: String,
+            otherDeviceId: String,
+            transactionId: String?
+    ): String? {
+        // should check if already one (and cancel it)
+        if (method == VerificationMethod.SAS) {
+            // TODO start SAS verification here, don't we need to see if there's
+            // a request?
+            TODO()
+        } else {
+            throw IllegalArgumentException("Unknown verification method")
+        }
+    }
+
+    override fun requestKeyVerificationInDMs(
+            methods: List<VerificationMethod>,
+            otherUserId: String,
+            roomId: String,
+            localId: String?
+    ): PendingVerificationRequest {
+        Timber.i("## SAS Requesting verification to user: $otherUserId in room $roomId")
+
+        // TODO cancel other active requests, create a new request here and
+        // dispatch it
+        TODO()
+    }
+
+    override fun requestKeyVerification(
+            methods: List<VerificationMethod>,
+            otherUserId: String,
+            otherDevices: List<String>?
+    ): PendingVerificationRequest {
+        // This was mostly a copy paste of the InDMs method, do the same here
+        TODO()
+    }
+
+    override fun cancelVerificationRequest(request: PendingVerificationRequest) {
+        // TODO get the request out of the olm machine and cancel here
+        TODO()
+    }
+
+    override fun declineVerificationRequestInDMs(
+            otherUserId: String,
+            transactionId: String,
+            roomId: String
+    ) {
+        // TODO get an existing verification request out of the olm machine and
+        // cancel it. update the pending request afterwards
+    }
+
+    override fun beginKeyVerificationInDMs(
+            method: VerificationMethod,
+            transactionId: String,
+            roomId: String,
+            otherUserId: String,
+            otherDeviceId: String
+    ): String {
+        // TODO fetch out the verification request nad start SAS, return the
+        // flow id
+        return ""
+    }
+
+    override fun readyPendingVerificationInDMs(
+            methods: List<VerificationMethod>,
+            otherUserId: String,
+            roomId: String,
+            transactionId: String
+    ): Boolean {
+        Timber.e("## TRYING TO READY PENDING ROOM VERIFICATION")
+        // TODO do the same as readyPendingVerification
+        return true
+    }
+
+    override fun readyPendingVerification(
+            methods: List<VerificationMethod>,
+            otherUserId: String,
+            transactionId: String
+    ): Boolean {
+        val request = this.olmMachine.getVerificationRequest(otherUserId, transactionId)
+
+        return if (request != null) {
+            val outgoingRequest = request.accept_with_methods(methods)
+
+            if (outgoingRequest != null) {
+                runBlocking { sendRequest(outgoingRequest) }
+                dispatchRequestUpdated(request.toPendingVerificationRequest())
+                true
+            } else {
+                false
+            }
+        } else {
+            false
+        }
+    }
+
+    suspend fun sendRequest(request: OutgoingVerificationRequest) {
+        when (request) {
+            is OutgoingVerificationRequest.ToDevice -> {
+                val adapter =
+                        MoshiProvider.providesMoshi()
+                                .adapter<Map<String, HashMap<String, Any>>>(Map::class.java)
+                val body = adapter.fromJson(request.body)!!
+
+                val userMap = MXUsersDevicesMap<Any>()
+                userMap.join(body)
+
+                val sendToDeviceParams = SendToDeviceTask.Params(request.eventType, userMap)
+                sendToDeviceTask.execute(sendToDeviceParams)
+            }
+            else -> {}
+        }
+
+        // TODO move this into the VerificationRequest and Verification classes?
+    }
+
+    override fun transactionUpdated(tx: VerificationTransaction) {
+        dispatchTxUpdated(tx)
+    }
+}