remove all ratchet when needed to get fresh senderKey from members

app/sql.js

@@ -171,6 +171,7 @@ module.exports = {
 
   getSenderKeys,
   createOrUpdateSenderKeys,
+  removeAllClosedGroupRatchets,
 };
 
 function generateUUID() {
@@ -923,6 +924,12 @@ async function createOrUpdateSenderKeys(data) {
   );
 }
 
+async function removeAllClosedGroupRatchets(groupId) {
+  await db.run(`DELETE FROM ${SENDER_KEYS_TABLE} WHERE groupId = $groupId;`, {
+    $groupId: groupId,
+  });
+}
+
 async function updateToLokiSchemaVersion4(currentVersion, instance) {
   if (currentVersion >= 4) {
     return;

js/modules/data.d.ts

@@ -412,3 +412,4 @@ export function getMessagesWithFileAttachments(
 // Sender Keys
 export function getSenderKeys(groupId: any, senderIdentity: any): Promise<any>;
 export function createOrUpdateSenderKeys(data: any): Promise<void>;
+export function removeAllClosedGroupRatchets(groupId: string): Promise<void>;

js/modules/data.js

@@ -196,6 +196,7 @@ module.exports = {
 
   getSenderKeys,
   createOrUpdateSenderKeys,
+  removeAllClosedGroupRatchets,
 };
 
 function init() {
@@ -704,6 +705,10 @@ async function createOrUpdateSenderKeys(data) {
   await channels.createOrUpdateSenderKeys(data);
 }
 
+async function removeAllClosedGroupRatchets(groupId) {
+  await channels.removeAllClosedGroupRatchets(groupId);
+}
+
 // Sessions
 
 async function createOrUpdateSession(data) {

ts/components/session/LeftPaneMessageSection.tsx

@@ -307,12 +307,7 @@ export class LeftPaneMessageSection extends React.Component<Props, State> {
         onButtonClick={async (
           groupName: string,
           groupMembers: Array<ContactType>
-        ) =>
-          this.onCreateClosedGroup(
-            groupName,
-            groupMembers
-          )
-        }
+        ) => this.onCreateClosedGroup(groupName, groupMembers)}
         searchTerm={searchTerm}
         updateSearch={this.updateSearchBound}
         showSpinner={loading}
@@ -497,13 +492,9 @@ export class LeftPaneMessageSection extends React.Component<Props, State> {
     groupName: string,
     groupMembers: Array<ContactType>
   ) {
-    await MainViewController.createClosedGroup(
-      groupName,
-      groupMembers,
-      () => {
-        this.handleToggleOverlay(undefined);
-      }
-    );
+    await MainViewController.createClosedGroup(groupName, groupMembers, () => {
+      this.handleToggleOverlay(undefined);
+    });
   }
 
   private handleNewSessionButtonClick() {

ts/receiver/contentMessage.ts

@@ -19,7 +19,6 @@ import { BlockedNumberController } from '../util/blockedNumberController';
 import { decryptWithSenderKey } from '../session/medium_group/ratchet';
 import { StringUtils } from '../session/utils';
 import { UserUtil } from '../util';
-import { getMessageQueue } from '../session';
 
 export async function handleContentMessage(envelope: EnvelopePlus) {
   try {
@@ -310,7 +309,7 @@ async function decrypt(
 
         const requestKeysMessage = new MediumGroupRequestKeysMessage(params);
         const sender = new PubKey(senderIdentity);
-        void getMessageQueue().send(sender, requestKeysMessage);
+        void libsession.getMessageQueue().send(sender, requestKeysMessage);
 
         return;
       }

ts/receiver/dataMessage.ts

@@ -279,10 +279,7 @@ export async function handleDataMessage(
   envelope: EnvelopePlus,
   dataMessage: SignalService.IDataMessage
 ): Promise<void> {
-  window.log.info(
-    'data message from',
-    getEnvelopeId(envelope)
-  );
+  window.log.info('data message from', getEnvelopeId(envelope));
 
   if (dataMessage.mediumGroupUpdate) {
     await handleMediumGroupUpdate(envelope, dataMessage.mediumGroupUpdate);

ts/receiver/mediumGroups.ts

@@ -13,7 +13,10 @@ import { BufferType } from '../session/utils/String';
 import { MultiDeviceProtocol } from '../session/protocols';
 import { ConversationModel } from '../../js/models/conversations';
 import { UserUtil } from '../util';
-import { RatchetState } from '../session/medium_group/senderKeys';
+import {
+  createSenderKeyForGroup,
+  RatchetState,
+} from '../session/medium_group/senderKeys';
 
 const toHex = (d: BufferType) => StringUtils.decode(d, 'hex');
 const fromHex = (d: string) => StringUtils.encode(d, 'hex');
@@ -344,6 +347,18 @@ async function handleMediumGroupChange(
 
   await convo.commit();
 
+  if (diff.leavingMembers && diff.leavingMembers.length > 0) {
+    // Send out the user's new ratchet to all members (minus the removed ones) using established channels
+    const userSenderKey = await createSenderKeyForGroup(groupId, primary);
+    window.log.warn(
+      'Sharing our new senderKey with remainingMembers via message',
+      members,
+      userSenderKey
+    );
+
+    await shareSenderKeys(groupId, members, userSenderKey);
+  }
+
   await removeFromCache(envelope);
 }
 

ts/session/medium_group/index.ts

@@ -641,7 +641,8 @@ async function sendGroupUpdateForMedium(
     getMessageQueue().events.addListener('success', async message => {
       if (message.identifier === params.identifier) {
         // console.log('Our first message encrypted with old sk is sent.');
-        // TODO Delete all ratchets (it's important that this happens * after * sending out the update)
+        // Delete all ratchets (it's important that this happens * after * sending out the update)
+        await Data.removeAllClosedGroupRatchets(groupId);
         if (isUserLeaving) {
           // nothing to do on desktop
         } else {

ts/session/medium_group/ratchet.ts

@@ -20,7 +20,8 @@ async function queueJobForNumber(number: string, runJob: any) {
         // tslint:disable-next-line no-dynamic-delete
         delete jobQueue[number];
       }
-    }).catch((e: any) => {
+    })
+    .catch((e: any) => {
       window.log.error('queueJobForNumber() Caught error', e);
     });
   return runCurrent;