diff --git a/lib/selectors/socket-selectors.js b/lib/selectors/socket-selectors.js
index 0b5c61c1c..39e490c89 100644
--- a/lib/selectors/socket-selectors.js
+++ b/lib/selectors/socket-selectors.js
@@ -1,185 +1,197 @@
 // @flow
 
 import { createSelector } from 'reselect';
 
 import { currentCalendarQuery } from './nav-selectors.js';
 import {
   serverEntryInfo,
   serverEntryInfosObject,
   filterRawEntryInfosByCalendarQuery,
 } from '../shared/entry-utils.js';
 import threadWatcher from '../shared/thread-watcher.js';
+import type { SignedIdentityKeysBlob } from '../types/crypto-types.js';
 import type { RawEntryInfo, CalendarQuery } from '../types/entry-types.js';
 import type { AppState } from '../types/redux-types.js';
 import type { ClientReportCreationRequest } from '../types/report-types.js';
 import {
   serverRequestTypes,
   type ClientServerRequest,
   type ClientClientResponse,
 } from '../types/request-types.js';
 import type { SessionState } from '../types/session-types.js';
 import type { OneTimeKeyGenerator } from '../types/socket-types.js';
 import type { RawThreadInfo } from '../types/thread-types.js';
 import type { CurrentUserInfo, UserInfos } from '../types/user-types.js';
 import { getConfig } from '../utils/config.js';
 import { minimumOneTimeKeysRequired } from '../utils/crypto-utils.js';
 import { values, hash } from '../utils/objects.js';
 
 const queuedReports: (
   state: AppState,
 ) => $ReadOnlyArray<ClientReportCreationRequest> = createSelector(
   (state: AppState) => state.reportStore.queuedReports,
   (
     mainQueuedReports: $ReadOnlyArray<ClientReportCreationRequest>,
   ): $ReadOnlyArray<ClientReportCreationRequest> => mainQueuedReports,
 );
 
 const getClientResponsesSelector: (
   state: AppState,
 ) => (
   calendarActive: boolean,
   oneTimeKeyGenerator: ?OneTimeKeyGenerator,
+  getSignedIdentityKeysBlob: ?() => SignedIdentityKeysBlob,
   serverRequests: $ReadOnlyArray<ClientServerRequest>,
 ) => $ReadOnlyArray<ClientClientResponse> = createSelector(
   (state: AppState) => state.threadStore.threadInfos,
   (state: AppState) => state.entryStore.entryInfos,
   (state: AppState) => state.userStore.userInfos,
   (state: AppState) => state.currentUserInfo,
   currentCalendarQuery,
   (
       threadInfos: { +[id: string]: RawThreadInfo },
       entryInfos: { +[id: string]: RawEntryInfo },
       userInfos: UserInfos,
       currentUserInfo: ?CurrentUserInfo,
       calendarQuery: (calendarActive: boolean) => CalendarQuery,
     ) =>
     (
       calendarActive: boolean,
       oneTimeKeyGenerator: ?OneTimeKeyGenerator,
+      getSignedIdentityKeysBlob: ?() => SignedIdentityKeysBlob,
       serverRequests: $ReadOnlyArray<ClientServerRequest>,
     ): $ReadOnlyArray<ClientClientResponse> => {
       const clientResponses = [];
       const serverRequestedPlatformDetails = serverRequests.some(
         request => request.type === serverRequestTypes.PLATFORM_DETAILS,
       );
       for (const serverRequest of serverRequests) {
         if (
           serverRequest.type === serverRequestTypes.PLATFORM &&
           !serverRequestedPlatformDetails
         ) {
           clientResponses.push({
             type: serverRequestTypes.PLATFORM,
             platform: getConfig().platformDetails.platform,
           });
         } else if (serverRequest.type === serverRequestTypes.PLATFORM_DETAILS) {
           clientResponses.push({
             type: serverRequestTypes.PLATFORM_DETAILS,
             platformDetails: getConfig().platformDetails,
           });
         } else if (serverRequest.type === serverRequestTypes.CHECK_STATE) {
           const filteredEntryInfos = filterRawEntryInfosByCalendarQuery(
             serverEntryInfosObject(values(entryInfos)),
             calendarQuery(calendarActive),
           );
           const hashResults = {};
           for (const key in serverRequest.hashesToCheck) {
             const expectedHashValue = serverRequest.hashesToCheck[key];
             let hashValue;
             if (key === 'threadInfos') {
               hashValue = hash(threadInfos);
             } else if (key === 'entryInfos') {
               hashValue = hash(filteredEntryInfos);
             } else if (key === 'userInfos') {
               hashValue = hash(userInfos);
             } else if (key === 'currentUserInfo') {
               hashValue = hash(currentUserInfo);
             } else if (key.startsWith('threadInfo|')) {
               const [, threadID] = key.split('|');
               hashValue = hash(threadInfos[threadID]);
             } else if (key.startsWith('entryInfo|')) {
               const [, entryID] = key.split('|');
               let rawEntryInfo = filteredEntryInfos[entryID];
               if (rawEntryInfo) {
                 rawEntryInfo = serverEntryInfo(rawEntryInfo);
               }
               hashValue = hash(rawEntryInfo);
             } else if (key.startsWith('userInfo|')) {
               const [, userID] = key.split('|');
               hashValue = hash(userInfos[userID]);
             } else {
               continue;
             }
             hashResults[key] = expectedHashValue === hashValue;
           }
 
           const { failUnmentioned } = serverRequest;
           if (failUnmentioned && failUnmentioned.threadInfos) {
             for (const threadID in threadInfos) {
               const key = `threadInfo|${threadID}`;
               const hashResult = hashResults[key];
               if (hashResult === null || hashResult === undefined) {
                 hashResults[key] = false;
               }
             }
           }
           if (failUnmentioned && failUnmentioned.entryInfos) {
             for (const entryID in filteredEntryInfos) {
               const key = `entryInfo|${entryID}`;
               const hashResult = hashResults[key];
               if (hashResult === null || hashResult === undefined) {
                 hashResults[key] = false;
               }
             }
           }
           if (failUnmentioned && failUnmentioned.userInfos) {
             for (const userID in userInfos) {
               const key = `userInfo|${userID}`;
               const hashResult = hashResults[key];
               if (hashResult === null || hashResult === undefined) {
                 hashResults[key] = false;
               }
             }
           }
 
           clientResponses.push({
             type: serverRequestTypes.CHECK_STATE,
             hashResults,
           });
         } else if (
           serverRequest.type === serverRequestTypes.MORE_ONE_TIME_KEYS &&
           oneTimeKeyGenerator
         ) {
           const keys: string[] = [];
           for (let i = 0; i < minimumOneTimeKeysRequired; ++i) {
             keys.push(oneTimeKeyGenerator(i));
           }
           clientResponses.push({
             type: serverRequestTypes.MORE_ONE_TIME_KEYS,
             keys,
           });
+        } else if (
+          serverRequest.type === serverRequestTypes.SIGNED_IDENTITY_KEYS_BLOB &&
+          getSignedIdentityKeysBlob
+        ) {
+          const signedIdentityKeysBlob = getSignedIdentityKeysBlob();
+          clientResponses.push({
+            type: serverRequestTypes.SIGNED_IDENTITY_KEYS_BLOB,
+            signedIdentityKeysBlob,
+          });
         }
       }
       return clientResponses;
     },
 );
 
 const sessionStateFuncSelector: (
   state: AppState,
 ) => (calendarActive: boolean) => SessionState = createSelector(
   (state: AppState) => state.messageStore.currentAsOf,
   (state: AppState) => state.updatesCurrentAsOf,
   currentCalendarQuery,
   (
       messagesCurrentAsOf: number,
       updatesCurrentAsOf: number,
       calendarQuery: (calendarActive: boolean) => CalendarQuery,
     ) =>
     (calendarActive: boolean): SessionState => ({
       calendarQuery: calendarQuery(calendarActive),
       messagesCurrentAsOf,
       updatesCurrentAsOf,
       watchedIDs: threadWatcher.getWatchedIDs(),
     }),
 );
 
 export { queuedReports, getClientResponsesSelector, sessionStateFuncSelector };
diff --git a/native/selectors/socket-selectors.js b/native/selectors/socket-selectors.js
index 50fb60cde..e8262309c 100644
--- a/native/selectors/socket-selectors.js
+++ b/native/selectors/socket-selectors.js
@@ -1,94 +1,97 @@
 // @flow
 
 import { createSelector } from 'reselect';
 
 import {
   getClientResponsesSelector,
   sessionStateFuncSelector,
 } from 'lib/selectors/socket-selectors.js';
 import { createOpenSocketFunction } from 'lib/shared/socket-utils.js';
+import type { SignedIdentityKeysBlob } from 'lib/types/crypto-types.js';
 import type {
   ClientServerRequest,
   ClientClientResponse,
 } from 'lib/types/request-types.js';
 import type {
   SessionIdentification,
   SessionState,
 } from 'lib/types/session-types.js';
 import type { OneTimeKeyGenerator } from 'lib/types/socket-types.js';
 
 import { calendarActiveSelector } from '../navigation/nav-selectors.js';
 import type { AppState } from '../redux/state-types.js';
 import type { NavPlusRedux } from '../types/selector-types.js';
 
 const openSocketSelector: (state: AppState) => () => WebSocket = createSelector(
   (state: AppState) => state.urlPrefix,
   // We don't actually use the cookie in the socket open function, but we do use
   // it in the initial message, and when the cookie changes the socket needs to
   // be reopened. By including the cookie here, whenever the cookie changes this
   // function will change, which tells the Socket component to restart the
   // connection.
   (state: AppState) => state.cookie,
   createOpenSocketFunction,
 );
 
 const sessionIdentificationSelector: (
   state: AppState,
 ) => SessionIdentification = createSelector(
   (state: AppState) => state.cookie,
   (cookie: ?string): SessionIdentification => ({ cookie }),
 );
 
 function oneTimeKeyGenerator(inc: number): string {
   // todo replace this hard code with something like
   // commCoreModule.generateOneTimeKeys()
   let str = Date.now().toString() + '_' + inc.toString() + '_';
   while (str.length < 43) {
     str += Math.random().toString(36).substr(2, 5);
   }
   str = str.substr(0, 43);
   return str;
 }
 
 const nativeGetClientResponsesSelector: (
   input: NavPlusRedux,
 ) => (
   serverRequests: $ReadOnlyArray<ClientServerRequest>,
 ) => $ReadOnlyArray<ClientClientResponse> = createSelector(
   (input: NavPlusRedux) => getClientResponsesSelector(input.redux),
   (input: NavPlusRedux) => calendarActiveSelector(input.navContext),
   (
       getClientResponsesFunc: (
         calendarActive: boolean,
         oneTimeKeyGenerator: ?OneTimeKeyGenerator,
+        getSignedIdentityKeysBlob: ?() => SignedIdentityKeysBlob,
         serverRequests: $ReadOnlyArray<ClientServerRequest>,
       ) => $ReadOnlyArray<ClientClientResponse>,
       calendarActive: boolean,
     ) =>
     (serverRequests: $ReadOnlyArray<ClientServerRequest>) =>
       getClientResponsesFunc(
         calendarActive,
         oneTimeKeyGenerator,
+        null,
         serverRequests,
       ),
 );
 
 const nativeSessionStateFuncSelector: (
   input: NavPlusRedux,
 ) => () => SessionState = createSelector(
   (input: NavPlusRedux) => sessionStateFuncSelector(input.redux),
   (input: NavPlusRedux) => calendarActiveSelector(input.navContext),
   (
       sessionStateFunc: (calendarActive: boolean) => SessionState,
       calendarActive: boolean,
     ) =>
     () =>
       sessionStateFunc(calendarActive),
 );
 
 export {
   openSocketSelector,
   sessionIdentificationSelector,
   nativeGetClientResponsesSelector,
   nativeSessionStateFuncSelector,
 };
diff --git a/web/selectors/socket-selectors.js b/web/selectors/socket-selectors.js
index 54ebfc2f4..fbc823ace 100644
--- a/web/selectors/socket-selectors.js
+++ b/web/selectors/socket-selectors.js
@@ -1,70 +1,72 @@
 // @flow
 
 import { createSelector } from 'reselect';
 
 import {
   getClientResponsesSelector,
   sessionStateFuncSelector,
 } from 'lib/selectors/socket-selectors.js';
 import { createOpenSocketFunction } from 'lib/shared/socket-utils.js';
+import type { SignedIdentityKeysBlob } from 'lib/types/crypto-types.js';
 import type {
   ClientServerRequest,
   ClientClientResponse,
 } from 'lib/types/request-types.js';
 import type {
   SessionIdentification,
   SessionState,
 } from 'lib/types/session-types.js';
 import type { OneTimeKeyGenerator } from 'lib/types/socket-types.js';
 
 import type { AppState } from '../redux/redux-setup.js';
 
 const openSocketSelector: (state: AppState) => () => WebSocket = createSelector(
   (state: AppState) => state.baseHref,
   createOpenSocketFunction,
 );
 
 const sessionIdentificationSelector: (
   state: AppState,
 ) => SessionIdentification = createSelector(
   (state: AppState) => state.sessionID,
   (sessionID: ?string): SessionIdentification => ({ sessionID }),
 );
 
 const webGetClientResponsesSelector: (
   state: AppState,
 ) => (
   serverRequests: $ReadOnlyArray<ClientServerRequest>,
 ) => $ReadOnlyArray<ClientClientResponse> = createSelector(
   getClientResponsesSelector,
   (state: AppState) => state.navInfo.tab === 'calendar',
   (
       getClientResponsesFunc: (
         calendarActive: boolean,
         oneTimeKeyGenerator: ?OneTimeKeyGenerator,
+        getSignedIdentityKeysBlob: ?() => SignedIdentityKeysBlob,
         serverRequests: $ReadOnlyArray<ClientServerRequest>,
       ) => $ReadOnlyArray<ClientClientResponse>,
       calendarActive: boolean,
     ) =>
     (serverRequests: $ReadOnlyArray<ClientServerRequest>) =>
-      getClientResponsesFunc(calendarActive, null, serverRequests),
+      getClientResponsesFunc(calendarActive, null, null, serverRequests),
 );
 
 const webSessionStateFuncSelector: (state: AppState) => () => SessionState =
   createSelector(
     sessionStateFuncSelector,
     (state: AppState) => state.navInfo.tab === 'calendar',
     (
         sessionStateFunc: (calendarActive: boolean) => SessionState,
         calendarActive: boolean,
       ) =>
       () =>
         sessionStateFunc(calendarActive),
   );
 
 export {
   openSocketSelector,
   sessionIdentificationSelector,
   webGetClientResponsesSelector,
   webSessionStateFuncSelector,
 };