Encryption should not hinder verification

src/@types/event.ts

@@ -63,6 +63,10 @@ export enum EventType {
     KeyVerificationCancel = "m.key.verification.cancel",
     KeyVerificationMac = "m.key.verification.mac",
     KeyVerificationDone = "m.key.verification.done",
+    KeyVerificationKey = "m.key.verification.key",
+    KeyVerificationAccept = "m.key.verification.accept",
+    // XXX this event is not yet supported by js-sdk
+    KeyVerificationReady = "m.key.verification.ready",
     // use of this is discouraged https://matrix.org/docs/spec/client_server/r0.6.1#m-room-message-feedback
     RoomMessageFeedback = "m.room.message.feedback",
     Reaction = "m.reaction",

src/crypto/algorithms/megolm.ts

@@ -36,6 +36,7 @@ import { DeviceInfo } from "../deviceinfo";
 import { IOlmSessionResult } from "../olmlib";
 import { DeviceInfoMap } from "../DeviceList";
 import { MatrixEvent } from "../../models/event";
+import { EventType, MsgType } from '../../@types/event';
 import { IEventDecryptionResult, IMegolmSessionData, IncomingRoomKeyRequest } from "../index";
 import { RoomKeyRequestState } from '../OutgoingRoomKeyRequestManager';
 import { OlmGroupSessionExtraData } from "../../@types/crypto";
@@ -1019,7 +1020,12 @@ class MegolmEncryption extends EncryptionAlgorithm {
             }
         }
 
-        const [devicesInRoom, blocked] = await this.getDevicesInRoom(room);
+        /**
+         * When using in-room messages and the room has encryption enabled,
+         * clients should ensure that encryption does not hinder the verification.
+         */
+        const forceDistributeToUnverified = this.isVerificationEvent(eventType, content);
+        const [devicesInRoom, blocked] = await this.getDevicesInRoom(room, forceDistributeToUnverified);
 
         // check if any of these devices are not yet known to the user.
         // if so, warn the user so they can verify or ignore.
@@ -1053,6 +1059,26 @@ class MegolmEncryption extends EncryptionAlgorithm {
         return encryptedContent;
     }
 
+    private isVerificationEvent(eventType: string, content: object): boolean {
+        switch (eventType) {
+            case EventType.KeyVerificationCancel:
+            case EventType.KeyVerificationDone:
+            case EventType.KeyVerificationMac:
+            case EventType.KeyVerificationStart:
+            case EventType.KeyVerificationKey:
+            case EventType.KeyVerificationReady:
+            case EventType.KeyVerificationAccept: {
+                return true;
+            }
+            case EventType.RoomMessage: {
+                return content['msgtype'] === MsgType.KeyVerificationRequest;
+            }
+            default: {
+                return false;
+            }
+        }
+    }
+
     /**
      * Forces the current outbound group session to be discarded such
      * that another one will be created next time an event is sent.
@@ -1119,14 +1145,19 @@ class MegolmEncryption extends EncryptionAlgorithm {
      * Get the list of unblocked devices for all users in the room
      *
      * @param {module:models/room} room
+     * @param forceDistributeToUnverified if set to true will include the unverified devices
+     * even if setting is set to block them (useful for verification)
      *
      * @return {Promise} Promise which resolves to an array whose
      *     first element is a map from userId to deviceId to deviceInfo indicating
      *     the devices that messages should be encrypted to, and whose second
      *     element is a map from userId to deviceId to data indicating the devices
      *     that are in the room but that have been blocked
      */
-    private async getDevicesInRoom(room: Room): Promise<[DeviceInfoMap, IBlockedMap]> {
+    private async getDevicesInRoom(
+        room: Room,
+        forceDistributeToUnverified = false,
+    ): Promise<[DeviceInfoMap, IBlockedMap]> {
         const members = await room.getEncryptionTargetMembers();
         const roomMembers = members.map(function(u) {
             return u.userId;
@@ -1161,7 +1192,7 @@ class MegolmEncryption extends EncryptionAlgorithm {
                 const deviceTrust = this.crypto.checkDeviceTrust(userId, deviceId);
 
                 if (userDevices[deviceId].isBlocked() ||
-                    (!deviceTrust.isVerified() && isBlacklisting)
+                    (!deviceTrust.isVerified() && isBlacklisting && !forceDistributeToUnverified)
                 ) {
                     if (!blocked[userId]) {
                         blocked[userId] = {};

src/crypto/verification/Base.ts

@@ -21,6 +21,7 @@ limitations under the License.
  */
 
 import { MatrixEvent } from '../../models/event';
+import { EventType } from '../../@types/event';
 import { logger } from '../../logger';
 import { DeviceInfo } from '../deviceinfo';
 import { newTimeoutError } from "./Error";
@@ -182,13 +183,13 @@ export class VerificationBase<
         } else if (e.getType() === this.expectedEvent) {
             // if we receive an expected m.key.verification.done, then just
             // ignore it, since we don't need to do anything about it
-            if (this.expectedEvent !== "m.key.verification.done") {
+            if (this.expectedEvent !== EventType.KeyVerificationDone) {
                 this.expectedEvent = undefined;
                 this.rejectEvent = undefined;
                 this.resetTimer();
                 this.resolveEvent(e);
             }
-        } else if (e.getType() === "m.key.verification.cancel") {
+        } else if (e.getType() === EventType.KeyVerificationCancel) {
             const reject = this.reject;
             this.reject = undefined;
             // there is only promise to reject if verify has been called
@@ -241,20 +242,20 @@ export class VerificationBase<
                     const sender = e.getSender();
                     if (sender !== this.userId) {
                         const content = e.getContent();
-                        if (e.getType() === "m.key.verification.cancel") {
+                        if (e.getType() === EventType.KeyVerificationCancel) {
                             content.code = content.code || "m.unknown";
                             content.reason = content.reason || content.body
                                 || "Unknown reason";
-                            this.send("m.key.verification.cancel", content);
+                            this.send(EventType.KeyVerificationCancel, content);
                         } else {
-                            this.send("m.key.verification.cancel", {
+                            this.send(EventType.KeyVerificationCancel, {
                                 code: "m.unknown",
                                 reason: content.body || "Unknown reason",
                             });
                         }
                     }
                 } else {
-                    this.send("m.key.verification.cancel", {
+                    this.send(EventType.KeyVerificationCancel, {
                         code: "m.unknown",
                         reason: e.toString(),
                     });

src/crypto/verification/Error.ts

@@ -21,11 +21,12 @@ limitations under the License.
  */
 
 import { MatrixEvent } from "../../models/event";
+import { EventType } from '../../@types/event';
 
 export function newVerificationError(code: string, reason: string, extraData: Record<string, any>): MatrixEvent {
     const content = Object.assign({}, { code, reason }, extraData);
     return new MatrixEvent({
-        type: "m.key.verification.cancel",
+        type: EventType.KeyVerificationCancel,
         content,
     });
 }

src/crypto/verification/SAS.ts

@@ -32,13 +32,14 @@ import {
 } from './Error';
 import { logger } from '../../logger';
 import { IContent, MatrixEvent } from "../../models/event";
+import { EventType } from '../../@types/event';
 
-const START_TYPE = "m.key.verification.start";
+const START_TYPE = EventType.KeyVerificationStart;
 
 const EVENTS = [
-    "m.key.verification.accept",
-    "m.key.verification.key",
-    "m.key.verification.mac",
+    EventType.KeyVerificationAccept,
+    EventType.KeyVerificationKey,
+    EventType.KeyVerificationMac,
 ];
 
 let olmutil: Utility;
@@ -329,7 +330,7 @@ export class SAS extends Base<SasEvent, EventHandlerMap> {
 
         let e;
         try {
-            e = await this.waitForEvent("m.key.verification.accept");
+            e = await this.waitForEvent(EventType.KeyVerificationAccept);
         } finally {
             this.waitingForAccept = false;
         }
@@ -351,11 +352,11 @@ export class SAS extends Base<SasEvent, EventHandlerMap> {
         const olmSAS = new global.Olm.SAS();
         try {
             this.ourSASPubKey = olmSAS.get_pubkey();
-            await this.send("m.key.verification.key", {
+            await this.send(EventType.KeyVerificationKey, {
                 key: this.ourSASPubKey,
             });
 
-            e = await this.waitForEvent("m.key.verification.key");
+            e = await this.waitForEvent(EventType.KeyVerificationKey);
             // FIXME: make sure event is properly formed
             content = e.getContent();
             const commitmentStr = content.key + anotherjson.stringify(startContent);
@@ -385,12 +386,12 @@ export class SAS extends Base<SasEvent, EventHandlerMap> {
             });
 
             [e] = await Promise.all([
-                this.waitForEvent("m.key.verification.mac")
+                this.waitForEvent(EventType.KeyVerificationMac)
                     .then((e) => {
                         // we don't expect any more messages from the other
                         // party, and they may send a m.key.verification.done
                         // when they're done on their end
-                        this.expectedEvent = "m.key.verification.done";
+                        this.expectedEvent = EventType.KeyVerificationDone;
                         return e;
                     }),
                 verifySAS,
@@ -423,7 +424,7 @@ export class SAS extends Base<SasEvent, EventHandlerMap> {
         const olmSAS = new global.Olm.SAS();
         try {
             const commitmentStr = olmSAS.get_pubkey() + anotherjson.stringify(content);
-            await this.send("m.key.verification.accept", {
+            await this.send(EventType.KeyVerificationAccept, {
                 key_agreement_protocol: keyAgreement,
                 hash: hashMethod,
                 message_authentication_code: macMethod,
@@ -432,13 +433,13 @@ export class SAS extends Base<SasEvent, EventHandlerMap> {
                 commitment: olmutil.sha256(commitmentStr),
             });
 
-            let e = await this.waitForEvent("m.key.verification.key");
+            let e = await this.waitForEvent(EventType.KeyVerificationKey);
             // FIXME: make sure event is properly formed
             content = e.getContent();
             this.theirSASPubKey = content.key;
             olmSAS.set_their_key(content.key);
             this.ourSASPubKey = olmSAS.get_pubkey();
-            await this.send("m.key.verification.key", {
+            await this.send(EventType.KeyVerificationKey, {
                 key: this.ourSASPubKey,
             });
 
@@ -461,12 +462,12 @@ export class SAS extends Base<SasEvent, EventHandlerMap> {
             });
 
             [e] = await Promise.all([
-                this.waitForEvent("m.key.verification.mac")
+                this.waitForEvent(EventType.KeyVerificationMac)
                     .then((e) => {
                         // we don't expect any more messages from the other
                         // party, and they may send a m.key.verification.done
                         // when they're done on their end
-                        this.expectedEvent = "m.key.verification.done";
+                        this.expectedEvent = EventType.KeyVerificationDone;
                         return e;
                     }),
                 verifySAS,
@@ -507,7 +508,7 @@ export class SAS extends Base<SasEvent, EventHandlerMap> {
             keyList.sort().join(","),
             baseInfo + "KEY_IDS",
         );
-        return this.send("m.key.verification.mac", { mac, keys });
+        return this.send(EventType.KeyVerificationMac, { mac, keys });
     }
 
     private async checkMAC(olmSAS: OlmSAS, content: IContent, method: string): Promise<void> {

src/crypto/verification/request/VerificationRequest.ts

@@ -25,6 +25,7 @@ import { QRCodeData, SCAN_QR_CODE_METHOD } from "../QRCode";
 import { IVerificationChannel } from "./Channel";
 import { MatrixClient } from "../../../client";
 import { MatrixEvent } from "../../../models/event";
+import { EventType } from '../../../@types/event';
 import { VerificationBase } from "../Base";
 import { VerificationMethod } from "../../index";
 import { TypedEventEmitter } from "../../../models/typed-event-emitter";
@@ -931,7 +932,7 @@ export class VerificationRequest<
     }
 
     public onVerifierFinished(): void {
-        this.channel.send("m.key.verification.done", {});
+        this.channel.send(EventType.KeyVerificationDone, {});
         this.verifierHasFinished = true;
         // move to .done phase
         const newTransitions = this.applyPhaseTransitions();