QR code: handle the case where other user can scan QR codes

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

@@ -55,11 +55,15 @@ import im.vector.matrix.android.internal.crypto.model.rest.KeyVerificationCancel
 import im.vector.matrix.android.internal.crypto.model.rest.KeyVerificationKey
 import im.vector.matrix.android.internal.crypto.model.rest.KeyVerificationMac
 import im.vector.matrix.android.internal.crypto.model.rest.KeyVerificationStart
+import im.vector.matrix.android.internal.crypto.model.rest.VERIFICATION_METHOD_QR_CODE_SCAN
 import im.vector.matrix.android.internal.crypto.model.rest.VERIFICATION_METHOD_RECIPROCATE
 import im.vector.matrix.android.internal.crypto.model.rest.VERIFICATION_METHOD_SAS
 import im.vector.matrix.android.internal.crypto.model.rest.supportedVerificationMethods
 import im.vector.matrix.android.internal.crypto.model.rest.toValue
 import im.vector.matrix.android.internal.crypto.store.IMXCryptoStore
+import im.vector.matrix.android.internal.crypto.verification.qrcode.QrCodeData
+import im.vector.matrix.android.internal.crypto.verification.qrcode.generateSharedSecret
+import im.vector.matrix.android.internal.crypto.verification.qrcode.toUrl
 import im.vector.matrix.android.internal.session.SessionScope
 import im.vector.matrix.android.internal.util.MatrixCoroutineDispatchers
 import kotlinx.coroutines.GlobalScope
@@ -72,6 +76,9 @@ import kotlin.collections.set
 
 @SessionScope
 internal class DefaultVerificationService @Inject constructor(
+        // TODO @UserId private val userId: String,
+        // TODO @DeviceId private val deviceId: String,
+        // TODO Do not use credential (do it in a dedicated commit)
         private val credentials: Credentials,
         private val cryptoStore: IMXCryptoStore,
         private val myDeviceInfoHolder: Lazy<MyDeviceInfoHolder>,
@@ -650,7 +657,63 @@ internal class DefaultVerificationService @Inject constructor(
             Timber.e("## SAS Received Ready for unknown request txId:${readyReq.transactionID} fromDevice ${readyReq.fromDevice}")
             return
         }
-        updatePendingRequest(existingRequest.copy(readyInfo = readyReq))
+
+        var myGeneratedSharedSecret: String? = null
+        val qrCodeText = readyReq.methods
+                // Check if other user is able to scan QR code
+                ?.takeIf { it.contains(VERIFICATION_METHOD_QR_CODE_SCAN) }
+                ?.let {
+                    // Build the QR code URL
+                    val requestEventId = existingRequest.transactionId ?: run {
+                        Timber.w("Unknown requestEventId")
+                        return@let null
+                    }
+
+                    val myMasterKey = crossSigningService.getMyCrossSigningKeys()
+                            ?.masterKey()
+                            ?.unpaddedBase64PublicKey
+                            ?: run {
+                                Timber.w("Unable to get my master key")
+                                return@let null
+                            }
+
+                    val otherUserMasterKey = crossSigningService.getUserCrossSigningKeys(existingRequest.otherUserId)
+                            ?.masterKey()
+                            ?.unpaddedBase64PublicKey
+                            ?: run {
+                                Timber.w("Unable to get other user master key")
+                                return@let null
+                            }
+
+                    val myDeviceId = credentials.deviceId
+                            ?: run {
+                                Timber.w("Unable to get my deviceId")
+                                return@let null
+                            }
+
+                    // TODO I'm pretty sure it's the correct key to put here
+                    val myDeviceKey = myDeviceInfoHolder.get().myDevice.fingerprint()!!
+
+                    val generatedSharedSecret = generateSharedSecret()
+                            .also { myGeneratedSharedSecret = it }
+                    QrCodeData(
+                            userId = credentials.userId,
+                            requestEventId = requestEventId,
+                            action = QrCodeData.ACTION_VERIFY,
+                            keys = hashMapOf(
+                                    myMasterKey to myMasterKey,
+                                    myDeviceId to myDeviceKey
+                            ),
+                            sharedSecret = generatedSharedSecret,
+                            otherUserKey = otherUserMasterKey
+                    ).toUrl()
+                }
+
+        updatePendingRequest(existingRequest.copy(
+                readyInfo = readyReq,
+                myGeneratedSecret = myGeneratedSharedSecret,
+                qrCodeText = qrCodeText
+        ))
     }
 
     private fun handleDoneReceived(senderId: String, doneInfo: VerificationInfo) {

matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/crypto/verification/PendingVerificationRequest.kt

@@ -37,7 +37,9 @@ data class PendingVerificationRequest(
         val readyInfo: VerificationInfoReady? = null,
         val cancelConclusion: CancelCode? = null,
         val isSuccessful: Boolean = false,
-        val handledByOtherSession: Boolean = false
+        val handledByOtherSession: Boolean = false,
+        val myGeneratedSecret: String? = null,
+        val qrCodeText: String? = null
 
 ) {
     val isReady: Boolean = readyInfo != null

vector/src/main/java/im/vector/riotx/features/crypto/verification/choose/VerificationChooseMethodController.kt

@@ -49,10 +49,10 @@ class VerificationChooseMethodController @Inject constructor(
                 notice(stringProvider.getString(R.string.verification_scan_notice))
             }
 
-            if (state.otherCanScanQrCode && !state.QRtext.isNullOrBlank()) {
+            if (state.otherCanScanQrCode && !state.qrCodeText.isNullOrBlank()) {
                 bottomSheetVerificationQrCodeItem {
                     id("qr")
-                    data(state.QRtext)
+                    data(state.qrCodeText)
                     animate(false)
                 }
 

vector/src/main/java/im/vector/riotx/features/crypto/verification/choose/VerificationChooseMethodViewModel.kt

@@ -37,7 +37,7 @@ data class VerificationChooseMethodViewState(
         val transactionId: String = "",
         val otherCanShowQrCode: Boolean = false,
         val otherCanScanQrCode: Boolean = false,
-        val QRtext: String? = null,
+        val qrCodeText: String? = null,
         val SASModeAvailable: Boolean = false
 ) : MvRxState
 
@@ -57,8 +57,7 @@ class VerificationChooseMethodViewModel @AssistedInject constructor(
             copy(
                     otherCanShowQrCode = pvr?.hasMethod(VerificationMethod.QR_CODE_SHOW) ?: false,
                     otherCanScanQrCode = pvr?.hasMethod(VerificationMethod.QR_CODE_SCAN) ?: false,
-                    // TODO
-                    QRtext = "https://www.example.org",
+                    qrCodeText = pvr?.qrCodeText,
                     SASModeAvailable = pvr?.hasMethod(VerificationMethod.SAS) ?: false
             )
         }
@@ -93,8 +92,7 @@ class VerificationChooseMethodViewModel @AssistedInject constructor(
                     transactionId = args.verificationId ?: "",
                     otherCanShowQrCode = pvr?.hasMethod(VerificationMethod.QR_CODE_SHOW) ?: false,
                     otherCanScanQrCode = pvr?.hasMethod(VerificationMethod.QR_CODE_SCAN) ?: false,
-                    // TODO
-                    QRtext = "https://www.example.org",
+                    qrCodeText = pvr?.qrCodeText,
                     SASModeAvailable = pvr?.hasMethod(VerificationMethod.SAS) ?: false
             )
         }