Notify other devices of acceptance of verification request

changelog.d/5724.sdk

@@ -0,0 +1 @@
+- Notifies other devices when a verification request sent from an Android device is accepted.`

matrix-sdk-android/src/androidTest/java/org/matrix/android/sdk/internal/crypto/verification/qrcode/VerificationTest.kt

@@ -27,11 +27,13 @@ import org.matrix.android.sdk.api.auth.UIABaseAuth
 import org.matrix.android.sdk.api.auth.UserInteractiveAuthInterceptor
 import org.matrix.android.sdk.api.auth.UserPasswordAuth
 import org.matrix.android.sdk.api.auth.registration.RegistrationFlowResponse
+import org.matrix.android.sdk.api.session.crypto.verification.CancelCode
 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.common.CommonTestHelper
 import org.matrix.android.sdk.common.CryptoTestHelper
+import org.matrix.android.sdk.common.SessionTestParams
 import org.matrix.android.sdk.common.TestConstants
 import java.util.concurrent.CountDownLatch
 import kotlin.coroutines.Continuation
@@ -252,4 +254,48 @@ class VerificationTest : InstrumentedTest {
 
         cryptoTestData.cleanUp(testHelper)
     }
+
+    @Test
+    fun test_selfVerificationAcceptedCancelsItForOtherSessions() {
+        val defaultSessionParams = SessionTestParams(true)
+        val testHelper = CommonTestHelper(context())
+
+        val aliceSessionToVerify = testHelper.createAccount(TestConstants.USER_ALICE, defaultSessionParams)
+        val aliceSessionThatVerifies = testHelper.logIntoAccount(aliceSessionToVerify.myUserId, TestConstants.PASSWORD, defaultSessionParams)
+        val aliceSessionThatReceivesCanceledEvent = testHelper.logIntoAccount(aliceSessionToVerify.myUserId, TestConstants.PASSWORD, defaultSessionParams)
+
+        val verificationMethods = listOf(VerificationMethod.SAS, VerificationMethod.QR_CODE_SCAN, VerificationMethod.QR_CODE_SHOW)
+
+        val serviceOfVerified = aliceSessionToVerify.cryptoService().verificationService()
+        val serviceOfVerifier = aliceSessionThatVerifies.cryptoService().verificationService()
+        val serviceOfUserWhoReceivesCancellation = aliceSessionThatReceivesCanceledEvent.cryptoService().verificationService()
+
+        serviceOfVerifier.addListener(object : VerificationService.Listener {
+            override fun verificationRequestCreated(pr: PendingVerificationRequest) {
+                // Accept verification request
+                serviceOfVerifier.readyPendingVerification(
+                        verificationMethods,
+                        pr.otherUserId,
+                        pr.transactionId!!,
+                )
+            }
+        })
+
+        serviceOfVerified.requestKeyVerification(
+                methods = verificationMethods,
+                otherUserId = aliceSessionToVerify.myUserId,
+                otherDevices = listOfNotNull(aliceSessionThatVerifies.sessionParams.deviceId, aliceSessionThatReceivesCanceledEvent.sessionParams.deviceId),
+        )
+
+        testHelper.waitWithLatch { latch ->
+            testHelper.retryPeriodicallyWithLatch(latch) {
+                val requests = serviceOfUserWhoReceivesCancellation.getExistingVerificationRequests(aliceSessionToVerify.myUserId)
+                requests.any { it.cancelConclusion == CancelCode.AcceptedByAnotherDevice }
+            }
+        }
+
+        testHelper.signOutAndClose(aliceSessionToVerify)
+        testHelper.signOutAndClose(aliceSessionThatVerifies)
+        testHelper.signOutAndClose(aliceSessionThatReceivesCanceledEvent)
+    }
 }

matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/session/crypto/verification/CancelCode.kt

@@ -28,7 +28,8 @@ enum class CancelCode(val value: String, val humanReadable: String) {
     MismatchedKeys("m.key_mismatch", "Key mismatch"),
     UserError("m.user_error", "User error"),
     MismatchedUser("m.user_mismatch", "User mismatch"),
-    QrCodeInvalid("m.qr_code.invalid", "Invalid QR code")
+    QrCodeInvalid("m.qr_code.invalid", "Invalid QR code"),
+    AcceptedByAnotherDevice("m.accepted", "Verification request accepted by another device")
 }
 
 fun safeValueOf(code: String?): CancelCode {

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

@@ -942,6 +942,22 @@ internal class DefaultVerificationService @Inject constructor(
                     readyInfo = readyReq
                 )
         )
+
+        notifyOthersOfAcceptance(readyReq.transactionId, readyReq.fromDevice)
+    }
+
+    /**
+     * Gets a list of device ids excluding the current one.
+     */
+    private fun getMyOtherDeviceIds(): List<String> = cryptoStore.getUserDevices(userId)?.keys?.filter { it != deviceId }.orEmpty()
+
+    /**
+     * Notifies other devices that the current verification transaction is being handled by [acceptedByDeviceId].
+     */
+    private fun notifyOthersOfAcceptance(transactionId: String, acceptedByDeviceId: String) {
+        val deviceIds = getMyOtherDeviceIds().filter { it != acceptedByDeviceId }
+        val transport = verificationTransportToDeviceFactory.createTransport(null)
+        transport.cancelTransaction(transactionId, userId, deviceIds, CancelCode.AcceptedByAnotherDevice)
     }
 
     private fun createQrCodeData(requestId: String?, otherUserId: String, otherDeviceId: String?): QrCodeData? {

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

@@ -49,6 +49,11 @@ internal interface VerificationTransport {
                           otherUserDeviceId: String?,
                           code: CancelCode)
 
+    fun cancelTransaction(transactionId: String,
+                          otherUserId: String,
+                          otherUserDeviceIds: List<String>,
+                          code: CancelCode)
+
     fun done(transactionId: String,
              onDone: (() -> Unit)?)
 

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

@@ -160,6 +160,9 @@ internal class VerificationTransportRoomMessage(
         }
     }
 
+    override fun cancelTransaction(transactionId: String, otherUserId: String, otherUserDeviceIds: List<String>, code: CancelCode) =
+            cancelTransaction(transactionId, otherUserId, null, code)
+
     override fun done(transactionId: String,
                       onDone: (() -> Unit)?) {
         Timber.d("## SAS sending done for $transactionId")

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

@@ -193,6 +193,27 @@ internal class VerificationTransportToDevice(
                 .executeBy(taskExecutor)
     }
 
+    override fun cancelTransaction(transactionId: String, otherUserId: String, otherUserDeviceIds: List<String>, code: CancelCode) {
+        Timber.d("## SAS canceling transaction $transactionId for reason $code")
+        val cancelMessage = KeyVerificationCancel.create(transactionId, code)
+        val contentMap = MXUsersDevicesMap<Any>()
+        val messages = otherUserDeviceIds.associateWith { cancelMessage }
+        contentMap.setObjects(otherUserId, messages)
+        sendToDeviceTask
+                .configureWith(SendToDeviceTask.Params(EventType.KEY_VERIFICATION_CANCEL, contentMap)) {
+                    this.callback = object : MatrixCallback<Unit> {
+                        override fun onSuccess(data: Unit) {
+                            Timber.v("## SAS verification [$transactionId] canceled for reason ${code.value}")
+                        }
+
+                        override fun onFailure(failure: Throwable) {
+                            Timber.e(failure, "## SAS verification [$transactionId] failed to cancel.")
+                        }
+                    }
+                }
+                .executeBy(taskExecutor)
+    }
+
     override fun createAccept(tid: String,
                               keyAgreementProtocol: String,
                               hash: String,