v32.3.0-rc.0

* Maybe run complement-crypto

* Use existing checkout

* Test that things fail if crypto breaks

* Fix test; run only on merge queue

* Prettier

* Maybe get it working in a merge queue

.github/actions/sign-release-tarball/action.yml

@@ -22,7 +22,7 @@ runs:
 
         - name: Upload tarball signature
           if: ${{ inputs.upload-url }}
-          uses: shogo82148/actions-upload-release-asset@5bd52f05dd8076794da5975d4c0a4f3bce7dd8f5 # v1
+          uses: shogo82148/actions-upload-release-asset@8f032eff0255912cc9c8455797fd6d72f25c7ab7 # v1
           with:
               upload_url: ${{ inputs.upload-url }}
               asset_path: ${{ env.VERSION }}.tar.gz.asc

.github/actions/upload-release-assets/action.yml

@@ -29,13 +29,13 @@ runs:
 
         - name: Upload asset signatures
           if: inputs.gpg-fingerprint
-          uses: shogo82148/actions-upload-release-asset@5bd52f05dd8076794da5975d4c0a4f3bce7dd8f5 # v1
+          uses: shogo82148/actions-upload-release-asset@8f032eff0255912cc9c8455797fd6d72f25c7ab7 # v1
           with:
               upload_url: ${{ inputs.upload-url }}
               asset_path: ${{ inputs.asset-path }}.asc
 
         - name: Upload assets
-          uses: shogo82148/actions-upload-release-asset@5bd52f05dd8076794da5975d4c0a4f3bce7dd8f5 # v1
+          uses: shogo82148/actions-upload-release-asset@8f032eff0255912cc9c8455797fd6d72f25c7ab7 # v1
           with:
               upload_url: ${{ inputs.upload-url }}
               asset_path: ${{ inputs.asset-path }}

.github/workflows/downstream-artifacts.yml

@@ -1,22 +0,0 @@
-name: Build downstream artifacts
-on:
-    merge_group:
-        types: [checks_requested]
-
-    pull_request: {}
-
-    # For now at least, we don't run this or the downstream-end-to-end-tests against pushes
-    # to develop or master.
-    #
-    #push:
-    #    branches: [develop, master]
-concurrency:
-    group: ${{ github.workflow }}-${{ github.ref }}
-    cancel-in-progress: true
-jobs:
-    build-element-web:
-        name: Build element-web
-        uses: matrix-org/matrix-react-sdk/.github/workflows/element-web.yaml@v3.96.1
-        with:
-            matrix-js-sdk-sha: ${{ github.sha }}
-            react-sdk-repository: matrix-org/matrix-react-sdk

.github/workflows/downstream-end-to-end-tests.yml

@@ -3,10 +3,16 @@
 
 name: matrix-react-sdk End to End Tests
 on:
-    workflow_run:
-        workflows: ["Build downstream artifacts"]
-        types:
-            - completed
+    merge_group:
+        types: [checks_requested]
+
+    pull_request: {}
+
+    # For now at least, we don't run this or the downstream-end-to-end-tests against pushes
+    # to develop or master.
+    #
+    #push:
+    #    branches: [develop, master]
 
 concurrency:
     group: ${{ github.workflow }}-${{ github.event.workflow_run.head_branch || github.run_id }}
@@ -15,44 +21,14 @@ concurrency:
 jobs:
     playwright:
         name: Playwright
-        # We only want to run the playwright tests on merge queue to prevent regressions
-        # from creeping in. They take a long time to run and consume multiple concurrent runners.
-        if: github.event.workflow_run.event == 'merge_group'
         uses: matrix-org/matrix-react-sdk/.github/workflows/end-to-end-tests.yaml@develop
         permissions:
             actions: read
             issues: read
-            statuses: write
             pull-requests: read
-            deployments: write
         with:
+            matrix-js-sdk-sha: ${{ github.sha }}
             react-sdk-repository: matrix-org/matrix-react-sdk
-        secrets:
-            ELEMENT_BOT_TOKEN: ${{ secrets.ELEMENT_BOT_TOKEN }}
-
-    # We want to make the Playwright tests a required check for the merge queue.
-    #
-    # Unfortunately, GitHub doesn't distinguish between "checks needed for branch
-    # protection" (ie, the things that must pass before the PR will even be added
-    # to the merge queue) and "checks needed in the merge queue". We just have to add
-    # the check to the branch protection list.
-    #
-    # Ergo, if we know we're not going to run the Playwright tests, we need to add a
-    # passing status check manually.
-    mark_skipped:
-        if: github.event.workflow_run.event != 'merge_group'
-        permissions:
-            statuses: write
-        runs-on: ubuntu-latest
-        steps:
-            - uses: Sibz/github-status-action@071b5370da85afbb16637d6eed8524a06bc2053e # v1
-              with:
-                  authToken: "${{ secrets.GITHUB_TOKEN }}"
-                  state: success
-                  description: Playwright skipped
-
-                  # Keep in step with the `context` that is updated by `Sibz/github-status-action`
-                  # in matrix-org/matrix-react-sdk/.github/workflows/end-to-end-tests.yaml.
-                  context: "${{ github.workflow }} / end-to-end-tests"
-
-                  sha: "${{ github.event.workflow_run.head_sha }}"
+            # We only want to run the playwright tests on merge queue to prevent regressions
+            # from creeping in. They take a long time to run and consume multiple concurrent runners.
+            skip: ${{ github.event_name != 'merge_group' }}

.github/workflows/release-drafter-workflow.yml

@@ -1,4 +1,5 @@
-name: Release Drafter
+# Workflow used by other workflows to generate draft releases.
+name: Release Drafter Reusable
 on:
     workflow_call:
         inputs:

.github/workflows/release-drafter.yml

@@ -1,3 +1,7 @@
+# Generates the draft release for the js-sdk
+# Normally triggered whenever anything is merged to the staging branch, but
+# also has a workflow dispatch trigger in case it needs running manually due
+# to failures / workflow updates etc.
 name: Release Drafter
 on:
     push:

.github/workflows/sonarcloud.yml

@@ -12,10 +12,6 @@ on:
                 type: boolean
                 required: false
                 description: "Whether to combine multiple LCOV and jest-sonar-report files in coverage artifact"
-            extra_args:
-                type: string
-                required: false
-                description: "Extra args to pass to SonarCloud"
 jobs:
     sonarqube:
         runs-on: ubuntu-latest
@@ -60,14 +56,14 @@ jobs:
 
             - id: extra_args
               run: |
-                  coverage=$(find coverage -type f -name '*lcov.info' | tr '\n' ',' | sed 's/,$//g')
-                  echo "reportPaths=$coverage" >> $GITHUB_OUTPUT
-                  reports=$(find coverage -type f -name 'jest-sonar-report*.xml' | tr '\n' ',' | sed 's/,$//g')
-                  echo "testExecutionReportPaths=$reports" >> $GITHUB_OUTPUT
+                  coverage=$(find coverage -type f -name '*lcov.info' -printf '%h/%f,' | tr -d '\r\n' | sed 's/,$//g')
+                  echo "sonar.javascript.lcov.reportPaths=$coverage" >> sonar-project.properties
+                  reports=$(find coverage -type f -name 'jest-sonar-report*.xml' -printf '%h/%f,' | tr -d '\r\n' | sed 's/,$//g')
+                  echo "sonar.testExecutionReportPaths=$reports" >> sonar-project.properties
 
             - name: "🩻 SonarCloud Scan"
               id: sonarcloud
-              uses: matrix-org/sonarcloud-workflow-action@v2.7
+              uses: matrix-org/sonarcloud-workflow-action@v3.2
               # workflow_run fails report against the develop commit always, we don't want that for PRs
               continue-on-error: ${{ github.event.workflow_run.head_branch != 'develop' }}
               with:
@@ -78,10 +74,6 @@ jobs:
                   branch: ${{ github.event.workflow_run.head_branch }}
                   revision: ${{ github.event.workflow_run.head_sha }}
                   token: ${{ secrets.SONAR_TOKEN }}
-                  extra_args: |
-                      ${{ inputs.extra_args }}
-                      -Dsonar.javascript.lcov.reportPaths=${{ steps.extra_args.outputs.reportPaths }}
-                      -Dsonar.testExecutionReportPaths=${{ steps.extra_args.outputs.testExecutionReportPaths }}
 
             - uses: Sibz/github-status-action@071b5370da85afbb16637d6eed8524a06bc2053e # v1
               if: always()

.github/workflows/tests.yml

@@ -71,6 +71,24 @@ jobs:
             disable_coverage: true
             matrix-js-sdk-sha: ${{ github.sha }}
 
+    complement-crypto:
+        name: "Run Complement Crypto tests"
+        if: github.event_name == 'merge_group'
+        uses: matrix-org/complement-crypto/.github/workflows/single_sdk_tests.yml@main
+        with:
+            use_js_sdk: "."
+
+    # we need this so the job is reported properly when run in a merge queue
+    downstream-complement-crypto:
+        name: Downstream Complement Crypto tests
+        runs-on: ubuntu-latest
+        if: always()
+        needs:
+            - complement-crypto
+        steps:
+            - if: needs.complement-crypto.result != 'skipped' && needs.complement-crypto.result != 'success'
+              run: exit 1
+
     # Hook for branch protection to skip downstream testing outside of merge queues
     # and skip sonarcloud coverage within merge queues
     downstream:

CHANGELOG.md

@@ -1,3 +1,18 @@
+Changes in [32.2.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v32.2.0) (2024-05-07)
+==================================================================================================
+## ✨ Features
+
+* Use a different error code for UTDs when user was not in the room ([#4172](https://github.com/matrix-org/matrix-js-sdk/pull/4172)). Contributed by @uhoreg.
+* Modernize window.crypto access constants ([#4169](https://github.com/matrix-org/matrix-js-sdk/pull/4169)). Contributed by @turt2live.
+* Improve compliance with MSC3266 ([#4155](https://github.com/matrix-org/matrix-js-sdk/pull/4155)). Contributed by @AndrewFerr.
+* Add comment to make clear that RoomStateEvent.Events does not update related objects in the js-sdk ([#4152](https://github.com/matrix-org/matrix-js-sdk/pull/4152)). Contributed by @toger5.
+* Crypto: use a new error code for UTDs from device-relative historical events ([#4139](https://github.com/matrix-org/matrix-js-sdk/pull/4139)). Contributed by @richvdh.
+
+## 🐛 Bug Fixes
+
+* Element-R: Fix rust migration when ssss secret are stored not encryted in cache (old legacy behavior) ([#4168](https://github.com/matrix-org/matrix-js-sdk/pull/4168)). Contributed by @BillCarsonFr.
+
+
 Changes in [32.1.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v32.1.0) (2024-04-23)
 ==================================================================================================
 ## ✨ Features

README.md

@@ -21,6 +21,10 @@ endpoints from before Matrix 1.1, for example.
 
 # Quickstart
 
+> [!IMPORTANT]
+> Servers may require or use authenticated endpoints for media (images, files, avatars, etc). See the
+> [Authenticated Media](#authenticated-media) section for information on how to enable support for this.
+
 Using `yarn` instead of `npm` is recommended. Please see the Yarn [install guide](https://classic.yarnpkg.com/en/docs/install)
 if you do not have it already.
 
@@ -89,6 +93,34 @@ Object.keys(client.store.rooms).forEach((roomId) => {
 });
 ```
 
+## Authenticated media
+
+Servers supporting [MSC3916](https://github.com/matrix-org/matrix-spec-proposals/pull/3916) will require clients, like
+yours, to include an `Authorization` header when `/download`ing or `/thumbnail`ing media. For NodeJS environments this
+may be as easy as the following code snippet, though web browsers may need to use [Service Workers](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API)
+to append the header when using the endpoints in `<img />` elements and similar.
+
+```javascript
+const downloadUrl = client.mxcUrlToHttp(
+    /*mxcUrl=*/ "mxc://example.org/abc123", // the MXC URI to download/thumbnail, typically from an event or profile
+    /*width=*/ undefined, // part of the thumbnail API. Use as required.
+    /*height=*/ undefined, // part of the thumbnail API. Use as required.
+    /*resizeMethod=*/ undefined, // part of the thumbnail API. Use as required.
+    /*allowDirectLinks=*/ false, // should generally be left `false`.
+    /*allowRedirects=*/ true, // implied supported with authentication
+    /*useAuthentication=*/ true, // the flag we're after in this example
+);
+const img = await fetch(downloadUrl, {
+    headers: {
+        Authorization: `Bearer ${client.getAccessToken()}`,
+    },
+});
+// Do something with `img`.
+```
+
+> [!WARNING]
+> In future the js-sdk will _only_ return authentication-required URLs, mandating population of the `Authorization` header.
+
 ## What does this SDK do?
 
 This SDK provides a full object model around the Matrix Client-Server API and emits

package.json

@@ -1,6 +1,6 @@
 {
     "name": "matrix-js-sdk",
-    "version": "32.1.0",
+    "version": "32.3.0-rc.0",
     "description": "Matrix Client-Server SDK for Javascript",
     "engines": {
         "node": ">=18.0.0"
@@ -102,11 +102,11 @@
         "eslint-config-prettier": "^9.0.0",
         "eslint-import-resolver-typescript": "^3.5.1",
         "eslint-plugin-import": "^2.26.0",
-        "eslint-plugin-jest": "^27.1.6",
+        "eslint-plugin-jest": "^28.0.0",
         "eslint-plugin-jsdoc": "^48.0.0",
         "eslint-plugin-matrix-org": "^1.0.0",
         "eslint-plugin-tsdoc": "^0.2.17",
-        "eslint-plugin-unicorn": "^51.0.0",
+        "eslint-plugin-unicorn": "^52.0.0",
         "fake-indexeddb": "^5.0.2",
         "fetch-mock": "9.11.0",
         "fetch-mock-jest": "^1.5.1",
@@ -115,7 +115,7 @@
         "jest-environment-jsdom": "^29.0.0",
         "jest-localstorage-mock": "^2.4.6",
         "jest-mock": "^29.0.0",
-        "knip": "^4.0.1",
+        "knip": "^5.0.0",
         "lint-staged": "^15.0.2",
         "matrix-mock-request": "^2.5.0",
         "node-fetch": "^2.7.0",

spec/integ/crypto/cross-signing.spec.ts

@@ -347,6 +347,67 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("cross-signing (%s)", (backend: s
 
             expect(isCrossSigningReady).toBeTruthy();
         });
+
+        it("should return false if identity is not trusted, even if the secrets are in 4S", async () => {
+            e2eKeyResponder.addCrossSigningData(SIGNED_CROSS_SIGNING_KEYS_DATA);
+
+            // Complete initial sync, to get the 4S account_data events stored
+            mockInitialApiRequests(aliceClient.getHomeserverUrl());
+
+            // For this test we need to have a well-formed 4S setup.
+            const mockSecretInfo = {
+                encrypted: {
+                    // Don't care about the actual values here, just need to be present for validation
+                    KeyId: {
+                        iv: "IVIVIVIVIVIVIV",
+                        ciphertext: "CIPHERTEXTB64",
+                        mac: "MACMACMAC",
+                    },
+                },
+            };
+            syncResponder.sendOrQueueSyncResponse({
+                next_batch: 1,
+                account_data: {
+                    events: [
+                        {
+                            type: "m.secret_storage.key.KeyId",
+                            content: {
+                                algorithm: "m.secret_storage.v1.aes-hmac-sha2",
+                                // iv and mac not relevant for this test
+                            },
+                        },
+                        {
+                            type: "m.secret_storage.default_key",
+                            content: {
+                                key: "KeyId",
+                            },
+                        },
+                        {
+                            type: "m.cross_signing.master",
+                            content: mockSecretInfo,
+                        },
+                        {
+                            type: "m.cross_signing.user_signing",
+                            content: mockSecretInfo,
+                        },
+                        {
+                            type: "m.cross_signing.self_signing",
+                            content: mockSecretInfo,
+                        },
+                    ],
+                },
+            });
+            await aliceClient.startClient();
+            await syncPromise(aliceClient);
+
+            // Sanity: ensure that the secrets are in 4S
+            const status = await aliceClient.getCrypto()!.getCrossSigningStatus();
+            expect(status.privateKeysInSecretStorage).toBeTruthy();
+
+            const isCrossSigningReady = await aliceClient.getCrypto()!.isCrossSigningReady();
+
+            expect(isCrossSigningReady).toBeFalsy();
+        });
     });
 
     describe("getCrossSigningKeyId", () => {

spec/integ/crypto/crypto.spec.ts

@@ -101,6 +101,7 @@ import {
 } from "./olm-utils";
 import { ToDevicePayload } from "../../../src/models/ToDeviceMessage";
 import { AccountDataAccumulator } from "../../test-utils/AccountDataAccumulator";
+import { UNSIGNED_MEMBERSHIP_FIELD } from "../../../src/@types/event";
 import { KnownMembership } from "../../../src/@types/membership";
 
 afterEach(() => {
@@ -108,6 +109,8 @@ afterEach(() => {
     // cf https://github.com/dumbmatter/fakeIndexedDB#wipingresetting-the-indexeddb-for-a-fresh-state
     // eslint-disable-next-line no-global-assign
     indexedDB = new IDBFactory();
+
+    jest.useRealTimers();
 });
 
 /**
@@ -467,6 +470,10 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("crypto (%s)", (backend: string,
     });
 
     describe("Unable to decrypt error codes", function () {
+        beforeEach(() => {
+            jest.useFakeTimers({ doNotFake: ["queueMicrotask"] });
+        });
+
         it("Decryption fails with UISI error", async () => {
             expectAliceKeyQuery({ device_keys: { "@alice:localhost": {} }, failures: {} });
             await startClientAndAwaitFirstSync();
@@ -474,11 +481,17 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("crypto (%s)", (backend: string,
             // A promise which resolves, with the MatrixEvent which wraps the event, once the decryption fails.
             const awaitDecryption = emitPromise(aliceClient, MatrixEventEvent.Decrypted);
 
+            // Ensure that the timestamp post-dates the creation of our device
+            const encryptedEvent = {
+                ...testData.ENCRYPTED_EVENT,
+                origin_server_ts: Date.now(),
+            };
+
             const syncResponse = {
                 next_batch: 1,
                 rooms: {
                     join: {
-                        [testData.TEST_ROOM_ID]: { timeline: { events: [testData.ENCRYPTED_EVENT] } },
+                        [testData.TEST_ROOM_ID]: { timeline: { events: [encryptedEvent] } },
                     },
                 },
             };
@@ -498,12 +511,17 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("crypto (%s)", (backend: string,
 
             await aliceClient.getCrypto()!.importRoomKeys([testData.RATCHTED_MEGOLM_SESSION_DATA]);
 
-            // Alice gets both the events in a single sync
+            // Ensure that the timestamp post-dates the creation of our device
+            const encryptedEvent = {
+                ...testData.ENCRYPTED_EVENT,
+                origin_server_ts: Date.now(),
+            };
+
             const syncResponse = {
                 next_batch: 1,
                 rooms: {
                     join: {
-                        [testData.TEST_ROOM_ID]: { timeline: { events: [testData.ENCRYPTED_EVENT] } },
+                        [testData.TEST_ROOM_ID]: { timeline: { events: [encryptedEvent] } },
                     },
                 },
             };
@@ -515,6 +533,151 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("crypto (%s)", (backend: string,
             expect(ev.decryptionFailureReason).toEqual(DecryptionFailureCode.OLM_UNKNOWN_MESSAGE_INDEX);
         });
 
+        describe("Historical events", () => {
+            async function sendEventAndAwaitDecryption(props: Partial<IEvent> = {}): Promise<MatrixEvent> {
+                // A promise which resolves, with the MatrixEvent which wraps the event, once the decryption fails.
+                const awaitDecryption = emitPromise(aliceClient, MatrixEventEvent.Decrypted);
+
+                // Ensure that the timestamp pre-dates the creation of our device: set it to 24 hours ago
+                const encryptedEvent = {
+                    ...testData.ENCRYPTED_EVENT,
+                    origin_server_ts: Date.now() - 24 * 3600 * 1000,
+                    ...props,
+                };
+
+                const syncResponse = {
+                    next_batch: 1,
+                    rooms: {
+                        join: {
+                            [testData.TEST_ROOM_ID]: { timeline: { events: [encryptedEvent] } },
+                        },
+                    },
+                };
+
+                syncResponder.sendOrQueueSyncResponse(syncResponse);
+                return await awaitDecryption;
+            }
+
+            newBackendOnly("fails with HISTORICAL_MESSAGE_BACKUP_NO_BACKUP when there is no backup", async () => {
+                fetchMock.get("path:/_matrix/client/v3/room_keys/version", {
+                    status: 404,
+                    body: { errcode: "M_NOT_FOUND", error: "No current backup version." },
+                });
+                expectAliceKeyQuery({ device_keys: { "@alice:localhost": {} }, failures: {} });
+                await startClientAndAwaitFirstSync();
+
+                const ev = await sendEventAndAwaitDecryption();
+                expect(ev.decryptionFailureReason).toEqual(DecryptionFailureCode.HISTORICAL_MESSAGE_NO_KEY_BACKUP);
+            });
+
+            newBackendOnly("fails with HISTORICAL_MESSAGE_BACKUP_UNCONFIGURED when the backup is broken", async () => {
+                fetchMock.get("path:/_matrix/client/v3/room_keys/version", {});
+                expectAliceKeyQuery({ device_keys: { "@alice:localhost": {} }, failures: {} });
+                await startClientAndAwaitFirstSync();
+
+                const ev = await sendEventAndAwaitDecryption();
+                expect(ev.decryptionFailureReason).toEqual(
+                    DecryptionFailureCode.HISTORICAL_MESSAGE_BACKUP_UNCONFIGURED,
+                );
+            });
+
+            newBackendOnly("fails with HISTORICAL_MESSAGE_WORKING_BACKUP when backup is working", async () => {
+                // The test backup data is signed by a dummy device. We'll need to tell Alice about the device, and
+                // later, tell her to trust it, so that she trusts the backup.
+                const e2eResponder = new E2EKeyResponder(aliceClient.getHomeserverUrl());
+                e2eResponder.addDeviceKeys(testData.SIGNED_TEST_DEVICE_DATA);
+                fetchMock.get("path:/_matrix/client/v3/room_keys/version", testData.SIGNED_BACKUP_DATA);
+                await startClientAndAwaitFirstSync();
+
+                await aliceClient
+                    .getCrypto()!
+                    .storeSessionBackupPrivateKey(
+                        Buffer.from(testData.BACKUP_DECRYPTION_KEY_BASE64, "base64"),
+                        testData.SIGNED_BACKUP_DATA.version!,
+                    );
+
+                // Tell Alice to trust the dummy device that signed the backup
+                const devices = await aliceClient.getCrypto()!.getUserDeviceInfo([TEST_USER_ID]);
+                expect(devices.get(TEST_USER_ID)!.keys()).toContain(testData.TEST_DEVICE_ID);
+                await aliceClient.getCrypto()!.setDeviceVerified(testData.TEST_USER_ID, testData.TEST_DEVICE_ID);
+
+                // Tell Alice to check and enable backup
+                await aliceClient.getCrypto()!.checkKeyBackupAndEnable();
+
+                // Sanity: Alice should now have working backup.
+                expect(await aliceClient.getCrypto()!.getActiveSessionBackupVersion()).toEqual(
+                    testData.SIGNED_BACKUP_DATA.version,
+                );
+
+                // Finally! we can check what happens when we get an event.
+                const ev = await sendEventAndAwaitDecryption();
+                expect(ev.decryptionFailureReason).toEqual(DecryptionFailureCode.HISTORICAL_MESSAGE_WORKING_BACKUP);
+            });
+
+            newBackendOnly("fails with NOT_JOINED if user is not member of room", async () => {
+                fetchMock.get("path:/_matrix/client/v3/room_keys/version", {
+                    status: 404,
+                    body: { errcode: "M_NOT_FOUND", error: "No current backup version." },
+                });
+                expectAliceKeyQuery({ device_keys: { "@alice:localhost": {} }, failures: {} });
+                await startClientAndAwaitFirstSync();
+
+                const ev = await sendEventAndAwaitDecryption({
+                    unsigned: {
+                        [UNSIGNED_MEMBERSHIP_FIELD.name]: "leave",
+                    },
+                });
+                expect(ev.decryptionFailureReason).toEqual(DecryptionFailureCode.HISTORICAL_MESSAGE_USER_NOT_JOINED);
+            });
+
+            newBackendOnly(
+                "fails with another error when the server reports user was a member of the room",
+                async () => {
+                    // This tests that when the server reports that the user
+                    // was invited at the time the event was sent, then we
+                    // don't get a HISTORICAL_MESSAGE_USER_NOT_JOINED error,
+                    // and instead get some other error, since the user should
+                    // have gotten the key for the event.
+                    fetchMock.get("path:/_matrix/client/v3/room_keys/version", {
+                        status: 404,
+                        body: { errcode: "M_NOT_FOUND", error: "No current backup version." },
+                    });
+                    expectAliceKeyQuery({ device_keys: { "@alice:localhost": {} }, failures: {} });
+                    await startClientAndAwaitFirstSync();
+
+                    const ev = await sendEventAndAwaitDecryption({
+                        unsigned: {
+                            [UNSIGNED_MEMBERSHIP_FIELD.name]: "invite",
+                        },
+                    });
+                    expect(ev.decryptionFailureReason).toEqual(DecryptionFailureCode.HISTORICAL_MESSAGE_NO_KEY_BACKUP);
+                },
+            );
+
+            newBackendOnly(
+                "fails with another error when the server reports user was a member of the room",
+                async () => {
+                    // This tests that when the server reports the user's
+                    // membership, and reports that the user was joined, then we
+                    // don't get a HISTORICAL_MESSAGE_USER_NOT_JOINED error, and
+                    // instead get some other error.
+                    fetchMock.get("path:/_matrix/client/v3/room_keys/version", {
+                        status: 404,
+                        body: { errcode: "M_NOT_FOUND", error: "No current backup version." },
+                    });
+                    expectAliceKeyQuery({ device_keys: { "@alice:localhost": {} }, failures: {} });
+                    await startClientAndAwaitFirstSync();
+
+                    const ev = await sendEventAndAwaitDecryption({
+                        unsigned: {
+                            [UNSIGNED_MEMBERSHIP_FIELD.name]: "join",
+                        },
+                    });
+                    expect(ev.decryptionFailureReason).toEqual(DecryptionFailureCode.HISTORICAL_MESSAGE_NO_KEY_BACKUP);
+                },
+            );
+        });
+
         it("Decryption fails with Unable to decrypt for other errors", async () => {
             expectAliceKeyQuery({ device_keys: { "@alice:localhost": {} }, failures: {} });
             await startClientAndAwaitFirstSync();
@@ -997,10 +1160,6 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("crypto (%s)", (backend: string,
             return encryptedMessage;
         }
 
-        afterEach(() => {
-            jest.useRealTimers();
-        });
-
         newBackendOnly("should rotate the session after 2 messages", async () => {
             expectAliceKeyQuery({ device_keys: { "@alice:localhost": {} }, failures: {} });
             await startClientAndAwaitFirstSync();
@@ -2184,10 +2343,6 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("crypto (%s)", (backend: string,
             jest.useFakeTimers({ doNotFake: ["queueMicrotask"] });
         });
 
-        afterEach(() => {
-            jest.useRealTimers();
-        });
-
         function awaitKeyUploadRequest(): Promise<{ keysCount: number; fallbackKeysCount: number }> {
             return new Promise((resolve) => {
                 const listener = (url: string, options: RequestInit) => {
@@ -2250,10 +2405,6 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("crypto (%s)", (backend: string,
     });
 
     describe("getUserDeviceInfo", () => {
-        afterEach(() => {
-            jest.useRealTimers();
-        });
-
         // From https://spec.matrix.org/v1.6/client-server-api/#post_matrixclientv3keysquery
         // Using extracted response from matrix.org, it needs to have real keys etc to pass old crypto verification
         const queryResponseBody = {
@@ -2742,10 +2893,6 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("crypto (%s)", (backend: string,
                 jest.useFakeTimers({ doNotFake: ["queueMicrotask"] });
             });
 
-            afterEach(() => {
-                jest.useRealTimers();
-            });
-
             it("Should be able to restore from 4S after bootstrap", async () => {
                 const backupVersion = "1";
                 await bootstrapSecurity(backupVersion);

spec/integ/crypto/megolm-backup.spec.ts

@@ -45,6 +45,7 @@ import { KeyBackupInfo, KeyBackupSession } from "../../../src/crypto-api/keyback
 import { IKeyBackup } from "../../../src/crypto/backup";
 import { flushPromises } from "../../test-utils/flushPromises";
 import { defer, IDeferred } from "../../../src/utils";
+import { DecryptionFailureCode } from "../../../src/crypto-api";
 
 const ROOM_ID = testData.TEST_ROOM_ID;
 
@@ -242,8 +243,17 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("megolm-keys backup (%s)", (backe
 
             const room = aliceClient.getRoom(ROOM_ID)!;
             const event = room.getLiveTimeline().getEvents()[0];
-            await advanceTimersUntil(awaitDecryption(event, { waitOnDecryptionFailure: true }));
 
+            // On the first decryption attempt, decryption fails.
+            await awaitDecryption(event);
+            expect(event.decryptionFailureReason).toEqual(
+                backend === "libolm"
+                    ? DecryptionFailureCode.MEGOLM_UNKNOWN_INBOUND_SESSION_ID
+                    : DecryptionFailureCode.HISTORICAL_MESSAGE_WORKING_BACKUP,
+            );
+
+            // Eventually, decryption succeeds.
+            await awaitDecryption(event, { waitOnDecryptionFailure: true });
             expect(event.getContent()).toEqual(testData.CLEAR_EVENT.content);
         });
 

spec/integ/matrix-client-methods.spec.ts

@@ -19,7 +19,16 @@ import { Mocked } from "jest-mock";
 import * as utils from "../test-utils/test-utils";
 import { CRYPTO_ENABLED, IStoredClientOpts, MatrixClient } from "../../src/client";
 import { MatrixEvent } from "../../src/models/event";
-import { Filter, KnockRoomOpts, MemoryStore, Method, Room, SERVICE_TYPES } from "../../src/matrix";
+import {
+    Filter,
+    JoinRule,
+    KnockRoomOpts,
+    MemoryStore,
+    Method,
+    Room,
+    RoomSummary,
+    SERVICE_TYPES,
+} from "../../src/matrix";
 import { TestClient } from "../TestClient";
 import { THREAD_RELATION_TYPE } from "../../src/models/thread";
 import { IFilterDefinition } from "../../src/filter";
@@ -1710,6 +1719,102 @@ describe("MatrixClient", function () {
             await Promise.all([client.unbindThreePid("email", "alice@server.com"), httpBackend.flushAllExpected()]);
         });
     });
+
+    describe("getRoomSummary", () => {
+        const roomId = "!foo:bar";
+        const encodedRoomId = encodeURIComponent(roomId);
+
+        const roomSummary: RoomSummary = {
+            "room_id": roomId,
+            "name": "My Room",
+            "avatar_url": "",
+            "topic": "My room topic",
+            "world_readable": false,
+            "guest_can_join": false,
+            "num_joined_members": 1,
+            "room_type": "",
+            "join_rule": JoinRule.Public,
+            "membership": "leave",
+            "im.nheko.summary.room_version": "6",
+            "im.nheko.summary.encryption": "algo",
+        };
+
+        const prefix = "/_matrix/client/unstable/im.nheko.summary/";
+        const suffix = `summary/${encodedRoomId}`;
+        const deprecatedSuffix = `rooms/${encodedRoomId}/summary`;
+
+        const errorUnrecogStatus = 404;
+        const errorUnrecogBody = {
+            errcode: "M_UNRECOGNIZED",
+            error: "Unsupported endpoint",
+        };
+
+        const errorBadreqStatus = 400;
+        const errorBadreqBody = {
+            errcode: "M_UNKNOWN",
+            error: "Invalid request",
+        };
+
+        it("should respond with a valid room summary object", () => {
+            httpBackend.when("GET", prefix + suffix).respond(200, roomSummary);
+
+            const prom = client.getRoomSummary(roomId).then((response) => {
+                expect(response).toEqual(roomSummary);
+            });
+
+            httpBackend.flush("");
+            return prom;
+        });
+
+        it("should allow fallback to the deprecated endpoint", () => {
+            httpBackend.when("GET", prefix + suffix).respond(errorUnrecogStatus, errorUnrecogBody);
+            httpBackend.when("GET", prefix + deprecatedSuffix).respond(200, roomSummary);
+
+            const prom = client.getRoomSummary(roomId).then((response) => {
+                expect(response).toEqual(roomSummary);
+            });
+
+            httpBackend.flush("");
+            return prom;
+        });
+
+        it("should respond to unsupported path with error", () => {
+            httpBackend.when("GET", prefix + suffix).respond(errorUnrecogStatus, errorUnrecogBody);
+            httpBackend.when("GET", prefix + deprecatedSuffix).respond(errorUnrecogStatus, errorUnrecogBody);
+
+            const prom = client.getRoomSummary(roomId).then(
+                function (response) {
+                    throw Error("request not failed");
+                },
+                function (error) {
+                    expect(error.httpStatus).toEqual(errorUnrecogStatus);
+                    expect(error.errcode).toEqual(errorUnrecogBody.errcode);
+                    expect(error.message).toEqual(`MatrixError: [${errorUnrecogStatus}] ${errorUnrecogBody.error}`);
+                },
+            );
+
+            httpBackend.flush("");
+            return prom;
+        });
+
+        it("should respond to invalid path arguments with error", () => {
+            httpBackend.when("GET", prefix).respond(errorBadreqStatus, errorBadreqBody);
+
+            const prom = client.getRoomSummary("notAroom").then(
+                function (response) {
+                    throw Error("request not failed");
+                },
+                function (error) {
+                    expect(error.httpStatus).toEqual(errorBadreqStatus);
+                    expect(error.errcode).toEqual(errorBadreqBody.errcode);
+                    expect(error.message).toEqual(`MatrixError: [${errorBadreqStatus}] ${errorBadreqBody.error}`);
+                },
+            );
+
+            httpBackend.flush("");
+            return prom;
+        });
+    });
 });
 
 function withThreadId(event: MatrixEvent, newThreadId: string): MatrixEvent {

spec/unit/content-repo.spec.ts

@@ -76,5 +76,29 @@ describe("ContentRepo", function () {
                 baseUrl + "/_matrix/media/v3/download/server.name/resourceid#automade",
             );
         });
+
+        it("should return an authenticated URL when requested", function () {
+            const mxcUri = "mxc://server.name/resourceid";
+            expect(getHttpUriForMxc(baseUrl, mxcUri, undefined, undefined, undefined, undefined, true, true)).toEqual(
+                baseUrl +
+                    "/_matrix/client/unstable/org.matrix.msc3916/media/download/server.name/resourceid?allow_redirect=true",
+            );
+            expect(getHttpUriForMxc(baseUrl, mxcUri, 64, 64, "scale", undefined, true, true)).toEqual(
+                baseUrl +
+                    "/_matrix/client/unstable/org.matrix.msc3916/media/thumbnail/server.name/resourceid?width=64&height=64&method=scale&allow_redirect=true",
+            );
+        });
+
+        it("should force-enable allow_redirects when useAuthentication is set true", function () {
+            const mxcUri = "mxc://server.name/resourceid";
+            expect(getHttpUriForMxc(baseUrl, mxcUri, undefined, undefined, undefined, undefined, false, true)).toEqual(
+                baseUrl +
+                    "/_matrix/client/unstable/org.matrix.msc3916/media/download/server.name/resourceid?allow_redirect=true",
+            );
+            expect(getHttpUriForMxc(baseUrl, mxcUri, 64, 64, "scale", undefined, false, true)).toEqual(
+                baseUrl +
+                    "/_matrix/client/unstable/org.matrix.msc3916/media/thumbnail/server.name/resourceid?width=64&height=64&method=scale&allow_redirect=true",
+            );
+        });
     });
 });

spec/unit/matrix-client.spec.ts

@@ -386,6 +386,9 @@ describe("MatrixClient", function () {
             expect(client.mxcUrlToHttp(mxc, 32, 46, "scale", false, true)).toBe(
                 getHttpUriForMxc(client.baseUrl, mxc, 32, 46, "scale", false, true),
             );
+            expect(client.mxcUrlToHttp(mxc, 32, 46, "scale", false, true, true)).toBe(
+                getHttpUriForMxc(client.baseUrl, mxc, 32, 46, "scale", false, true, true),
+            );
         });
     });
 

spec/unit/rust-crypto/PerSessionKeyBackupDownloader.spec.ts

@@ -90,7 +90,7 @@ describe("PerSessionKeyBackupDownloader", () => {
 
         mockRustBackupManager = {
             getActiveBackupVersion: jest.fn(),
-            requestKeyBackupVersion: jest.fn(),
+            getServerBackupInfo: jest.fn(),
             importBackedUpRoomKeys: jest.fn(),
             createBackupDecryptor: jest.fn().mockReturnValue(mockBackupDecryptor),
             on: jest.fn().mockImplementation((event, listener) => {
@@ -135,7 +135,7 @@ describe("PerSessionKeyBackupDownloader", () => {
                 decryptionKey: RustSdkCryptoJs.BackupDecryptionKey.fromBase64(TestData.BACKUP_DECRYPTION_KEY_BASE64),
             } as unknown as RustSdkCryptoJs.BackupKeys);
 
-            mockRustBackupManager.requestKeyBackupVersion.mockResolvedValue(TestData.SIGNED_BACKUP_DATA);
+            mockRustBackupManager.getServerBackupInfo.mockResolvedValue(TestData.SIGNED_BACKUP_DATA);
         });
 
         it("Should download and import a missing key from backup", async () => {
@@ -155,8 +155,11 @@ describe("PerSessionKeyBackupDownloader", () => {
 
             downloader.onDecryptionKeyMissingError(roomId, sessionId);
 
+            // `isKeyBackupDownloadConfigured` is false until the config is proven.
+            expect(downloader.isKeyBackupDownloadConfigured()).toBe(false);
             await expectAPICall;
             await awaitKeyImported.promise;
+            expect(downloader.isKeyBackupDownloadConfigured()).toBe(true);
             expect(mockRustBackupManager.createBackupDecryptor).toHaveBeenCalledTimes(1);
         });
 
@@ -313,6 +316,9 @@ describe("PerSessionKeyBackupDownloader", () => {
 
             expect(getConfigSpy).toHaveBeenCalledTimes(1);
             expect(getConfigSpy).toHaveReturnedWith(Promise.resolve(null));
+
+            // isKeyBackupDownloadConfigured remains false
+            expect(downloader.isKeyBackupDownloadConfigured()).toBe(false);
         });
 
         it("Should not query server if backup not active", async () => {
@@ -328,6 +334,9 @@ describe("PerSessionKeyBackupDownloader", () => {
 
             expect(getConfigSpy).toHaveBeenCalledTimes(1);
             expect(getConfigSpy).toHaveReturnedWith(Promise.resolve(null));
+
+            // isKeyBackupDownloadConfigured remains false
+            expect(downloader.isKeyBackupDownloadConfigured()).toBe(false);
         });
 
         it("Should stop if backup key is not cached", async () => {
@@ -344,6 +353,9 @@ describe("PerSessionKeyBackupDownloader", () => {
 
             expect(getConfigSpy).toHaveBeenCalledTimes(1);
             expect(getConfigSpy).toHaveReturnedWith(Promise.resolve(null));
+
+            // isKeyBackupDownloadConfigured remains false
+            expect(downloader.isKeyBackupDownloadConfigured()).toBe(false);
         });
 
         it("Should stop if backup key cached as wrong version", async () => {
@@ -363,6 +375,9 @@ describe("PerSessionKeyBackupDownloader", () => {
 
             expect(getConfigSpy).toHaveBeenCalledTimes(1);
             expect(getConfigSpy).toHaveReturnedWith(Promise.resolve(null));
+
+            // isKeyBackupDownloadConfigured remains false
+            expect(downloader.isKeyBackupDownloadConfigured()).toBe(false);
         });
 
         it("Should stop if backup key version does not match the active one", async () => {
@@ -382,13 +397,16 @@ describe("PerSessionKeyBackupDownloader", () => {
 
             expect(getConfigSpy).toHaveBeenCalledTimes(1);
             expect(getConfigSpy).toHaveReturnedWith(Promise.resolve(null));
+
+            // isKeyBackupDownloadConfigured remains false
+            expect(downloader.isKeyBackupDownloadConfigured()).toBe(false);
         });
     });
 
     describe("Given Backup state update", () => {
         it("After initial sync, when backup becomes trusted it should request keys for past requests", async () => {
             // there is a backup
-            mockRustBackupManager.requestKeyBackupVersion.mockResolvedValue(TestData.SIGNED_BACKUP_DATA);
+            mockRustBackupManager.getServerBackupInfo.mockResolvedValue(TestData.SIGNED_BACKUP_DATA);
 
             // but at this point it's not trusted and we don't have the key
             mockRustBackupManager.getActiveBackupVersion.mockResolvedValue(null);
@@ -410,6 +428,7 @@ describe("PerSessionKeyBackupDownloader", () => {
 
             // @ts-ignore access to private property
             expect(downloader.hasConfigurationProblem).toEqual(true);
+            expect(downloader.isKeyBackupDownloadConfigured()).toBe(false);
 
             // Now the backup becomes trusted
             mockRustBackupManager.getActiveBackupVersion.mockResolvedValue(TestData.SIGNED_BACKUP_DATA.version!);
@@ -423,6 +442,7 @@ describe("PerSessionKeyBackupDownloader", () => {
             mockEmitter.emit(CryptoEvent.KeyBackupStatus, true);
 
             await jest.runAllTimersAsync();
+            expect(downloader.isKeyBackupDownloadConfigured()).toBe(true);
 
             await a0Imported;
             await a1Imported;
@@ -434,7 +454,7 @@ describe("PerSessionKeyBackupDownloader", () => {
     describe("Error cases", () => {
         beforeEach(async () => {
             // there is a backup
-            mockRustBackupManager.requestKeyBackupVersion.mockResolvedValue(TestData.SIGNED_BACKUP_DATA);
+            mockRustBackupManager.getServerBackupInfo.mockResolvedValue(TestData.SIGNED_BACKUP_DATA);
             // It's trusted
             mockRustBackupManager.getActiveBackupVersion.mockResolvedValue(TestData.SIGNED_BACKUP_DATA.version!);
             // And we have the key in cache

spec/unit/rust-crypto/rust-crypto.spec.ts

@@ -304,6 +304,56 @@ describe("initRustCrypto", () => {
             }
         }, 10000);
 
+        it("migrates data from a legacy crypto store when secret are not encrypted", async () => {
+            const PICKLE_KEY = "pickle1234";
+            const legacyStore = new MemoryCryptoStore();
+
+            // It's possible for old sessions to directly store the secrets as raw UInt8Array,
+            // so we need to support that in the migration code.
+            // See https://github.com/matrix-org/matrix-js-sdk/commit/c81f11df0afd4d0da3b088892745ae2f8ba1c4a7
+            async function storeSecretKeyInClear(type: string, key: Uint8Array, store: CryptoStore) {
+                // @ts-ignore The API to store raw UInt8Array does not exist anymore, so we need that for this test.
+                store.privateKeys[type as keyof SecretStorePrivateKeys] = key;
+            }
+
+            // Populate the legacy store with some test data
+            const storeSecretKey = (type: string, key: string) =>
+                storeSecretKeyInClear(type, new TextEncoder().encode(key), legacyStore);
+
+            await legacyStore.storeAccount({}, "not a real account");
+            await storeSecretKey("master", "master key");
+            await storeSecretKey("self_signing", "ssk");
+            await storeSecretKey("user_signing", "usk");
+
+            fetchMock.get("path:/_matrix/client/v3/room_keys/version", 404);
+
+            function legacyMigrationProgressListener(progress: number, total: number): void {
+                logger.log(`migrated ${progress} of ${total}`);
+            }
+
+            await initRustCrypto({
+                logger,
+                http: makeMatrixHttpApi(),
+                userId: TEST_USER,
+                deviceId: TEST_DEVICE_ID,
+                secretStorage: {} as ServerSideSecretStorage,
+                cryptoCallbacks: {} as CryptoCallbacks,
+                storePrefix: "storePrefix",
+                storePassphrase: "storePassphrase",
+                legacyCryptoStore: legacyStore,
+                legacyPickleKey: PICKLE_KEY,
+                legacyMigrationProgressListener,
+            });
+
+            const data = mocked(Migration.migrateBaseData).mock.calls[0][0];
+            expect(data.pickledAccount).toEqual("not a real account");
+            expect(data.userId!.toString()).toEqual(TEST_USER);
+            expect(data.deviceId!.toString()).toEqual(TEST_DEVICE_ID);
+            expect(atob(data.privateCrossSigningMasterKey!)).toEqual("master key");
+            expect(atob(data.privateCrossSigningUserSigningKey!)).toEqual("usk");
+            expect(atob(data.privateCrossSigningSelfSigningKey!)).toEqual("ssk");
+        });
+
         it("handles megolm sessions with no `keysClaimed`", async () => {
             const legacyStore = new MemoryCryptoStore();
             legacyStore.storeAccount({}, "not a real account");

src/@types/event.ts

@@ -298,6 +298,13 @@ export const LOCAL_NOTIFICATION_SETTINGS_PREFIX = new UnstableValue(
  */
 export const UNSIGNED_THREAD_ID_FIELD = new UnstableValue("thread_id", "org.matrix.msc4023.thread_id");
 
+/**
+ * https://github.com/matrix-org/matrix-spec-proposals/pull/4115
+ *
+ * @experimental
+ */
+export const UNSIGNED_MEMBERSHIP_FIELD = new UnstableValue("membership", "io.element.msc4115.membership");
+
 /**
  * @deprecated in favour of {@link EncryptedFile}
  */

src/@types/partials.ts

@@ -45,14 +45,6 @@ export enum RestrictedAllowType {
     RoomMembership = "m.room_membership",
 }
 
-export interface IJoinRuleEventContent {
-    join_rule: JoinRule; // eslint-disable-line camelcase
-    allow?: {
-        type: RestrictedAllowType;
-        room_id: string; // eslint-disable-line camelcase
-    }[];
-}
-
 export enum GuestAccess {
     CanJoin = "can_join",
     Forbidden = "forbidden",

src/@types/state_events.ts

@@ -15,7 +15,7 @@ limitations under the License.
 */
 
 import { RoomType } from "./event";
-import { GuestAccess, HistoryVisibility, RestrictedAllowType } from "./partials";
+import { GuestAccess, HistoryVisibility, JoinRule, RestrictedAllowType } from "./partials";
 import { ImageInfo } from "./media";
 import { PolicyRecommendation } from "../models/invites-ignorer";
 
@@ -36,6 +36,7 @@ export interface RoomCreateEventContent {
 }
 
 export interface RoomJoinRulesEventContent {
+    join_rule: JoinRule;
     allow?: {
         room_id: string;
         type: RestrictedAllowType;

src/client.ts

@@ -865,10 +865,24 @@ interface IThirdPartyUser {
     fields: object;
 }
 
-interface IRoomSummary extends Omit<IPublicRoomsChunkRoom, "canonical_alias" | "aliases"> {
-    room_type?: RoomType;
-    membership?: Membership;
-    is_encrypted: boolean;
+/**
+ * The summary of a room as defined by an initial version of MSC3266 and implemented in Synapse
+ * Proposed at https://github.com/matrix-org/matrix-doc/pull/3266
+ */
+export interface RoomSummary extends Omit<IPublicRoomsChunkRoom, "canonical_alias" | "aliases"> {
+    /**
+     * The current membership of this user in the room.
+     * Usually "leave" if the room is fetched over federation.
+     */
+    "membership"?: Membership;
+    /**
+     * Version of the room.
+     */
+    "im.nheko.summary.room_version"?: string;
+    /**
+     * The encryption algorithm used for this room, if the room is encrypted.
+     */
+    "im.nheko.summary.encryption"?: string;
 }
 
 interface IRoomKeysResponse {
@@ -4862,10 +4876,10 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
                 pathTemplate = "/rooms/$roomId/state/$eventType/$stateKey";
             }
             path = utils.encodeUri(pathTemplate, pathParams);
-        } else if (event.isRedaction()) {
+        } else if (event.isRedaction() && event.event.redacts) {
             const pathTemplate = `/rooms/$roomId/redact/$redactsEventId/$txnId`;
             path = utils.encodeUri(pathTemplate, {
-                $redactsEventId: event.event.redacts!,
+                $redactsEventId: event.event.redacts,
                 ...pathParams,
             });
         } else {
@@ -5761,7 +5775,12 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * anyone they share a room with. If false, will return null for such URLs.
      * @param allowRedirects - If true, the caller supports the URL being 307 or
      * 308 redirected to another resource upon request. If false, redirects
-     * are not expected.
+     * are not expected. Implied `true` when `useAuthentication` is `true`.
+     * @param useAuthentication - If true, the caller supports authenticated
+     * media and wants an authentication-required URL. Note that server support
+     * for authenticated media will *not* be checked - it is the caller's responsibility
+     * to do so before calling this function. Note also that `useAuthentication`
+     * implies `allowRedirects`. Defaults to false (unauthenticated endpoints).
      * @returns the avatar URL or null.
      */
     public mxcUrlToHttp(
@@ -5771,8 +5790,18 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         resizeMethod?: string,
         allowDirectLinks?: boolean,
         allowRedirects?: boolean,
+        useAuthentication?: boolean,
     ): string | null {
-        return getHttpUriForMxc(this.baseUrl, mxcUrl, width, height, resizeMethod, allowDirectLinks, allowRedirects);
+        return getHttpUriForMxc(
+            this.baseUrl,
+            mxcUrl,
+            width,
+            height,
+            resizeMethod,
+            allowDirectLinks,
+            allowRedirects,
+            useAuthentication,
+        );
     }
 
     /**
@@ -9786,11 +9815,21 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
      * @param roomIdOrAlias - The ID or alias of the room to get the summary of.
      * @param via - The list of servers which know about the room if only an ID was provided.
      */
-    public async getRoomSummary(roomIdOrAlias: string, via?: string[]): Promise<IRoomSummary> {
-        const path = utils.encodeUri("/rooms/$roomid/summary", { $roomid: roomIdOrAlias });
-        return this.http.authedRequest(Method.Get, path, { via }, undefined, {
+    public async getRoomSummary(roomIdOrAlias: string, via?: string[]): Promise<RoomSummary> {
+        const paramOpts = {
             prefix: "/_matrix/client/unstable/im.nheko.summary",
-        });
+        };
+        try {
+            const path = utils.encodeUri("/summary/$roomid", { $roomid: roomIdOrAlias });
+            return await this.http.authedRequest(Method.Get, path, { via }, undefined, paramOpts);
+        } catch (e) {
+            if (e instanceof MatrixError && e.errcode === "M_UNRECOGNIZED") {
+                const path = utils.encodeUri("/rooms/$roomid/summary", { $roomid: roomIdOrAlias });
+                return await this.http.authedRequest(Method.Get, path, { via }, undefined, paramOpts);
+            } else {
+                throw e;
+            }
+        }
     }
 
     /**

src/content-repo.ts

@@ -30,7 +30,12 @@ import { encodeParams } from "./utils";
  * for such URLs.
  * @param allowRedirects - If true, the caller supports the URL being 307 or
  * 308 redirected to another resource upon request. If false, redirects
- * are not expected.
+ * are not expected. Implied `true` when `useAuthentication` is `true`.
+ * @param useAuthentication - If true, the caller supports authenticated
+ * media and wants an authentication-required URL. Note that server support
+ * for authenticated media will *not* be checked - it is the caller's responsibility
+ * to do so before calling this function. Note also that `useAuthentication`
+ * implies `allowRedirects`. Defaults to false (unauthenticated endpoints).
  * @returns The complete URL to the content.
  */
 export function getHttpUriForMxc(
@@ -41,6 +46,7 @@ export function getHttpUriForMxc(
     resizeMethod?: string,
     allowDirectLinks = false,
     allowRedirects?: boolean,
+    useAuthentication?: boolean,
 ): string {
     if (typeof mxc !== "string" || !mxc) {
         return "";
@@ -52,8 +58,23 @@ export function getHttpUriForMxc(
             return "";
         }
     }
+
+    if (useAuthentication) {
+        allowRedirects = true; // per docs (MSC3916 always expects redirects)
+
+        // Dev note: MSC3916 (as of writing) removes `allow_redirect` entirely, but
+        // for explicitness we set it here. This makes it slightly more obvious to
+        // callers, hopefully.
+    }
+
     let serverAndMediaId = mxc.slice(6); // strips mxc://
-    let prefix = "/_matrix/media/v3/download/";
+    let prefix: string;
+    if (useAuthentication) {
+        // TODO: Use stable once available (requires FCP on MSC3916).
+        prefix = "/_matrix/client/unstable/org.matrix.msc3916/media/download/";
+    } else {
+        prefix = "/_matrix/media/v3/download/";
+    }
     const params: Record<string, string> = {};
 
     if (width) {
@@ -68,7 +89,12 @@ export function getHttpUriForMxc(
     if (Object.keys(params).length > 0) {
         // these are thumbnailing params so they probably want the
         // thumbnailing API...
-        prefix = "/_matrix/media/v3/thumbnail/";
+        if (useAuthentication) {
+            // TODO: Use stable once available (requires FCP on MSC3916).
+            prefix = "/_matrix/client/unstable/org.matrix.msc3916/media/thumbnail/";
+        } else {
+            prefix = "/_matrix/media/v3/thumbnail/";
+        }
     }
 
     if (typeof allowRedirects === "boolean") {

src/crypto-api.ts

@@ -542,6 +542,29 @@ export enum DecryptionFailureCode {
     /** Message was encrypted with a Megolm session which has been shared with us, but in a later ratchet state. */
     OLM_UNKNOWN_MESSAGE_INDEX = "OLM_UNKNOWN_MESSAGE_INDEX",
 
+    /**
+     * Message was sent before the current device was created; there is no key backup on the server, so this
+     * decryption failure is expected.
+     */
+    HISTORICAL_MESSAGE_NO_KEY_BACKUP = "HISTORICAL_MESSAGE_NO_KEY_BACKUP",
+
+    /**
+     * Message was sent before the current device was created; there was a key backup on the server, but we don't
+     * seem to have access to the backup. (Probably we don't have the right key.)
+     */
+    HISTORICAL_MESSAGE_BACKUP_UNCONFIGURED = "HISTORICAL_MESSAGE_BACKUP_UNCONFIGURED",
+
+    /**
+     * Message was sent before the current device was created; there was a (usable) key backup on the server, but we
+     * still can't decrypt. (Either the session isn't in the backup, or we just haven't gotten around to checking yet.)
+     */
+    HISTORICAL_MESSAGE_WORKING_BACKUP = "HISTORICAL_MESSAGE_WORKING_BACKUP",
+
+    /**
+     * Message was sent when the user was not a member of the room.
+     */
+    HISTORICAL_MESSAGE_USER_NOT_JOINED = "HISTORICAL_MESSAGE_USER_NOT_JOINED",
+
     /** Unknown or unclassified error. */
     UNKNOWN_ERROR = "UNKNOWN_ERROR",
 

src/crypto/crypto.ts

@@ -16,9 +16,9 @@ limitations under the License.
 
 import { logger } from "../logger";
 
-export let crypto = globalThis.window?.crypto;
-export let subtleCrypto = globalThis.window?.crypto?.subtle ?? global.window?.crypto?.webkitSubtle;
-export let TextEncoder = globalThis.window?.TextEncoder;
+export let crypto = globalThis.crypto;
+export let subtleCrypto = crypto?.subtle ?? crypto?.webkitSubtle; // TODO: Stop using webkitSubtle fallback
+export let TextEncoder = globalThis.TextEncoder;
 
 /* eslint-disable @typescript-eslint/no-var-requires */
 if (!crypto) {

src/crypto/store/memory-crypto-store.ts

@@ -37,6 +37,17 @@ import { IOlmDevice } from "../algorithms/megolm";
 import { IRoomEncryption } from "../RoomList";
 import { InboundGroupSessionData } from "../OlmDevice";
 
+function encodeSessionKey(senderCurve25519Key: string, sessionId: string): string {
+    return encodeURIComponent(senderCurve25519Key) + "/" + encodeURIComponent(sessionId);
+}
+
+function decodeSessionKey(key: string): { senderKey: string; sessionId: string } {
+    const keyParts = key.split("/");
+    const senderKey = decodeURIComponent(keyParts[0]);
+    const sessionId = decodeURIComponent(keyParts[1]);
+    return { senderKey, sessionId };
+}
+
 /**
  * Internal module. in-memory storage for e2e.
  */
@@ -481,20 +492,14 @@ export class MemoryCryptoStore implements CryptoStore {
         txn: unknown,
         func: (groupSession: InboundGroupSessionData | null, groupSessionWithheld: IWithheld | null) => void,
     ): void {
-        const k = senderCurve25519Key + "/" + sessionId;
+        const k = encodeSessionKey(senderCurve25519Key, sessionId);
         func(this.inboundGroupSessions[k] || null, this.inboundGroupSessionsWithheld[k] || null);
     }
 
     public getAllEndToEndInboundGroupSessions(txn: unknown, func: (session: ISession | null) => void): void {
         for (const key of Object.keys(this.inboundGroupSessions)) {
-            // we can't use split, as the components we are trying to split out
-            // might themselves contain '/' characters. We rely on the
-            // senderKey being a (32-byte) curve25519 key, base64-encoded
-            // (hence 43 characters long).
-
             func({
-                senderKey: key.slice(0, 43),
-                sessionId: key.slice(44),
+                ...decodeSessionKey(key),
                 sessionData: this.inboundGroupSessions[key],
             });
         }
@@ -507,7 +512,7 @@ export class MemoryCryptoStore implements CryptoStore {
         sessionData: InboundGroupSessionData,
         txn: unknown,
     ): void {
-        const k = senderCurve25519Key + "/" + sessionId;
+        const k = encodeSessionKey(senderCurve25519Key, sessionId);
         if (this.inboundGroupSessions[k] === undefined) {
             this.inboundGroupSessions[k] = sessionData;
         }
@@ -519,7 +524,8 @@ export class MemoryCryptoStore implements CryptoStore {
         sessionData: InboundGroupSessionData,
         txn: unknown,
     ): void {
-        this.inboundGroupSessions[senderCurve25519Key + "/" + sessionId] = sessionData;
+        const k = encodeSessionKey(senderCurve25519Key, sessionId);
+        this.inboundGroupSessions[k] = sessionData;
     }
 
     public storeEndToEndInboundGroupSessionWithheld(
@@ -528,7 +534,7 @@ export class MemoryCryptoStore implements CryptoStore {
         sessionData: IWithheld,
         txn: unknown,
     ): void {
-        const k = senderCurve25519Key + "/" + sessionId;
+        const k = encodeSessionKey(senderCurve25519Key, sessionId);
         this.inboundGroupSessionsWithheld[k] = sessionData;
     }
 
@@ -554,8 +560,7 @@ export class MemoryCryptoStore implements CryptoStore {
         const result: SessionExtended[] = [];
         for (const [key, session] of Object.entries(this.inboundGroupSessions)) {
             result.push({
-                senderKey: key.slice(0, 43),
-                sessionId: key.slice(44),
+                ...decodeSessionKey(key),
                 sessionData: session,
                 needsBackup: key in this.sessionsNeedingBackup,
             });
@@ -584,7 +589,7 @@ export class MemoryCryptoStore implements CryptoStore {
         sessions: { senderKey: string; sessionId: string }[],
     ): Promise<void> {
         for (const { senderKey, sessionId } of sessions) {
-            const k = senderKey + "/" + sessionId;
+            const k = encodeSessionKey(senderKey, sessionId);
             delete this.inboundGroupSessions[k];
         }
     }
@@ -614,8 +619,7 @@ export class MemoryCryptoStore implements CryptoStore {
         for (const session in this.sessionsNeedingBackup) {
             if (this.inboundGroupSessions[session]) {
                 sessions.push({
-                    senderKey: session.slice(0, 43),
-                    sessionId: session.slice(44),
+                    ...decodeSessionKey(session),
                     sessionData: this.inboundGroupSessions[session],
                 });
                 if (limit && session.length >= limit) {
@@ -632,7 +636,7 @@ export class MemoryCryptoStore implements CryptoStore {
 
     public unmarkSessionsNeedingBackup(sessions: ISession[]): Promise<void> {
         for (const session of sessions) {
-            const sessionKey = session.senderKey + "/" + session.sessionId;
+            const sessionKey = encodeSessionKey(session.senderKey, session.sessionId);
             delete this.sessionsNeedingBackup[sessionKey];
         }
         return Promise.resolve();
@@ -640,7 +644,7 @@ export class MemoryCryptoStore implements CryptoStore {
 
     public markSessionsNeedingBackup(sessions: ISession[]): Promise<void> {
         for (const session of sessions) {
-            const sessionKey = session.senderKey + "/" + session.sessionId;
+            const sessionKey = encodeSessionKey(session.senderKey, session.sessionId);
             this.sessionsNeedingBackup[sessionKey] = true;
         }
         return Promise.resolve();

src/crypto/verification/QRCode.ts

@@ -74,7 +74,7 @@ export class ReciprocateQRCode extends Base {
         await new Promise<void>((resolve, reject) => {
             this.reciprocateQREvent = {
                 confirm: resolve,
-                cancel: () => reject(newUserCancelledError()),
+                cancel: (): void => reject(newUserCancelledError()),
             };
             this.emit(QrCodeEvent.ShowReciprocateQr, this.reciprocateQREvent);
         });

src/crypto/verification/SAS.ts

@@ -308,8 +308,8 @@ export class SAS extends Base {
                         reject(err);
                     }
                 },
-                cancel: () => reject(newUserCancelledError()),
-                mismatch: () => reject(newMismatchedSASError()),
+                cancel: (): void => reject(newUserCancelledError()),
+                mismatch: (): void => reject(newMismatchedSASError()),
             };
             this.emit(SasEvent.ShowSas, this.sasEvent);
         });

src/http-api/method.ts

@@ -19,4 +19,7 @@ export enum Method {
     Put = "PUT",
     Post = "POST",
     Delete = "DELETE",
+    Options = "OPTIONS",
+    Head = "HEAD",
+    Patch = "PATCH",
 }

src/matrix.ts

@@ -77,6 +77,7 @@ export * from "./@types/extensible_events";
 export * from "./@types/IIdentityServerProvider";
 export * from "./models/room-summary";
 export * from "./models/event-status";
+export type { RoomSummary } from "./client";
 export * as ContentHelpers from "./content-helpers";
 export * as SecretStorage from "./secret-storage";
 export type { ICryptoCallbacks } from "./crypto"; // used to be located here
@@ -104,6 +105,10 @@ export { IdentityProviderBrand, SSOAction } from "./@types/auth";
 export type { ISSOFlow as SSOFlow, LoginFlow } from "./@types/auth";
 export type { IHierarchyRelation as HierarchyRelation, IHierarchyRoom as HierarchyRoom } from "./@types/spaces";
 export { LocationAssetType } from "./@types/location";
+/**
+ * @deprecated in favour of RoomJoinRulesEventContent on the types export
+ */
+export type { RoomJoinRulesEventContent as IJoinRuleEventContent } from "./@types/state_events";
 
 /**
  * Types supporting cryptography.

src/matrixrtc/MatrixRTCSession.ts

@@ -136,7 +136,6 @@ export class MatrixRTCSession extends TypedEventEmitter<MatrixRTCSessionEvent, M
         for (const memberEvent of callMemberEvents) {
             const eventMemberships: CallMembershipData[] = memberEvent.getContent()["memberships"];
             if (eventMemberships === undefined) {
-                logger.debug(`Ignoring malformed member event from ${memberEvent.getSender()}: no memberships section`);
                 continue;
             }
             if (!Array.isArray(eventMemberships)) {

src/models/event.ts

@@ -31,6 +31,7 @@ import {
     RelationType,
     ToDeviceMessageId,
     UNSIGNED_THREAD_ID_FIELD,
+    UNSIGNED_MEMBERSHIP_FIELD,
 } from "../@types/event";
 import { Crypto } from "../crypto";
 import { deepSortedObjectEntries, internaliseString } from "../utils";
@@ -76,6 +77,7 @@ export interface IUnsigned {
     "invite_room_state"?: StrippedState[];
     "m.relations"?: Record<RelationType | string, any>; // No common pattern for aggregated relations
     [UNSIGNED_THREAD_ID_FIELD.name]?: string;
+    [UNSIGNED_MEMBERSHIP_FIELD.name]?: Membership | string;
 }
 
 export interface IThreadBundledRelationship {
@@ -721,6 +723,22 @@ export class MatrixEvent extends TypedEventEmitter<MatrixEventEmittedEvents, Mat
         return this.event.state_key !== undefined;
     }
 
+    /**
+     * Get the user's room membership at the time the event was sent, as reported
+     * by the server.  This uses MSC4115.
+     *
+     * @returns The user's room membership, or `undefined` if the server does
+     *   not report it.
+     */
+    public getMembershipAtEvent(): Membership | string | undefined {
+        const unsigned = this.getUnsigned();
+        if (typeof unsigned[UNSIGNED_MEMBERSHIP_FIELD.name] === "string") {
+            return unsigned[UNSIGNED_MEMBERSHIP_FIELD.name];
+        } else {
+            return undefined;
+        }
+    }
+
     /**
      * Replace the content of this event with encrypted versions.
      * (This is used when sending an event; it should not be used by applications).

src/models/room-state.ts

@@ -20,12 +20,13 @@ import { isNumber, removeHiddenChars } from "../utils";
 import { EventType, UNSTABLE_MSC2716_MARKER } from "../@types/event";
 import { IEvent, MatrixEvent, MatrixEventEvent } from "./event";
 import { MatrixClient } from "../client";
-import { GuestAccess, HistoryVisibility, IJoinRuleEventContent, JoinRule } from "../@types/partials";
+import { GuestAccess, HistoryVisibility, JoinRule } from "../@types/partials";
 import { TypedEventEmitter } from "./typed-event-emitter";
 import { Beacon, BeaconEvent, BeaconEventHandlerMap, getBeaconInfoIdentifier, BeaconIdentifier } from "./beacon";
 import { TypedReEmitter } from "../ReEmitter";
 import { M_BEACON, M_BEACON_INFO } from "../@types/beacon";
 import { KnownMembership } from "../@types/membership";
+import { RoomJoinRulesEventContent } from "../@types/state_events";
 
 export interface IMarkerFoundOptions {
     /** Whether the timeline was empty before the marker event arrived in the
@@ -78,6 +79,8 @@ export enum RoomStateEvent {
 export type RoomStateEventHandlerMap = {
     /**
      * Fires whenever the event dictionary in room state is updated.
+     * This does not guarantee that any related objects (like RoomMember) have been updated.
+     * Use RoomStateEvent.Update for that.
      * @param event - The matrix event which caused this event to fire.
      * @param state - The room state whose RoomState.events dictionary
      * was updated.
@@ -960,7 +963,7 @@ export class RoomState extends TypedEventEmitter<EmittedEvents, EventHandlerMap>
      */
     public getJoinRule(): JoinRule {
         const joinRuleEvent = this.getStateEvents(EventType.RoomJoinRules, "");
-        const joinRuleContent: Partial<IJoinRuleEventContent> = joinRuleEvent?.getContent() ?? {};
+        const joinRuleContent: Partial<RoomJoinRulesEventContent> = joinRuleEvent?.getContent() ?? {};
         return joinRuleContent["join_rule"] || JoinRule.Invite;
     }
 

src/oidc/validate.ts

@@ -15,7 +15,7 @@ limitations under the License.
 */
 
 import { jwtDecode } from "jwt-decode";
-import { OidcMetadata, SigninResponse } from "oidc-client-ts";
+import { IdTokenClaims, OidcMetadata, SigninResponse } from "oidc-client-ts";
 
 import { logger } from "../logger";
 import { OidcError } from "./error";
@@ -139,28 +139,7 @@ export function isValidatedIssuerMetadata(
     validateOIDCIssuerWellKnown(metadata);
 }
 
-/**
- * Standard JWT claims.
- *
- * @see https://datatracker.ietf.org/doc/html/rfc7519#section-4.1
- */
-interface JwtClaims {
-    [claim: string]: unknown;
-    /** The "iss" (issuer) claim identifies the principal that issued the JWT. */
-    iss?: string;
-    /** The "sub" (subject) claim identifies the principal that is the subject of the JWT. */
-    sub?: string;
-    /** The "aud" (audience) claim identifies the recipients that the JWT is intended for. */
-    aud?: string | string[];
-    /** The "exp" (expiration time) claim identifies the expiration time on or after which the JWT MUST NOT be accepted for processing. */
-    exp?: number;
-    // unused claims excluded
-}
-interface IdTokenClaims extends JwtClaims {
-    nonce?: string;
-}
-
-const decodeIdToken = (token: string): IdTokenClaims => {
+export const decodeIdToken = (token: string): IdTokenClaims => {
     try {
         return jwtDecode<IdTokenClaims>(token);
     } catch (error) {
@@ -276,7 +255,7 @@ export type BearerTokenResponse = {
     expires_in?: number;
     // from oidc-client-ts
     expires_at?: number;
-    id_token?: string;
+    id_token: string;
 };
 
 /**

src/rust-crypto/PerSessionKeyBackupDownloader.ts

@@ -17,7 +17,7 @@ limitations under the License.
 import * as RustSdkCryptoJs from "@matrix-org/matrix-sdk-crypto-wasm";
 import { OlmMachine } from "@matrix-org/matrix-sdk-crypto-wasm";
 
-import { Curve25519AuthData, KeyBackupSession } from "../crypto-api/keybackup";
+import { Curve25519AuthData, KeyBackupInfo, KeyBackupSession } from "../crypto-api/keybackup";
 import { Logger } from "../logger";
 import { ClientPrefix, IHttpOpts, MatrixError, MatrixHttpApi, Method } from "../http-api";
 import { RustBackupManager } from "./backup";
@@ -76,7 +76,11 @@ type Configuration = {
 export class PerSessionKeyBackupDownloader {
     private stopped = false;
 
-    /** The version and decryption key to use with current backup if all set up correctly */
+    /**
+     * The version and decryption key to use with current backup if all set up correctly.
+     *
+     * Will not be set unless `hasConfigurationProblem` is `false`.
+     */
     private configuration: Configuration | null = null;
 
     /** We remember when a session was requested and not found in backup to avoid query again too soon.
@@ -119,6 +123,24 @@ export class PerSessionKeyBackupDownloader {
         backupManager.on(CryptoEvent.KeyBackupDecryptionKeyCached, this.onBackupStatusChanged);
     }
 
+    /**
+     * Check if key download is successfully configured and active.
+     *
+     * @return `true` if key download is correctly configured and active; otherwise `false`.
+     */
+    public isKeyBackupDownloadConfigured(): boolean {
+        return this.configuration !== null;
+    }
+
+    /**
+     * Return the details of the latest backup on the server, when we last checked.
+     *
+     * This is just a convenience method to expose {@link RustBackupManager.getServerBackupInfo}.
+     */
+    public async getServerBackupInfo(): Promise<KeyBackupInfo | null | undefined> {
+        return await this.backupManager.getServerBackupInfo();
+    }
+
     /**
      * Called when a MissingRoomKey or UnknownMessageIndex decryption error is encountered.
      *
@@ -410,7 +432,7 @@ export class PerSessionKeyBackupDownloader {
     private async internalCheckFromServer(): Promise<Configuration | null> {
         let currentServerVersion = null;
         try {
-            currentServerVersion = await this.backupManager.requestKeyBackupVersion();
+            currentServerVersion = await this.backupManager.getServerBackupInfo();
         } catch (e) {
             this.logger.debug(`Backup: error while checking server version: ${e}`);
             this.hasConfigurationProblem = true;

src/rust-crypto/backup.ts

@@ -58,6 +58,16 @@ interface KeyBackupCreationInfo {
 export class RustBackupManager extends TypedEventEmitter<RustBackupCryptoEvents, RustBackupCryptoEventMap> {
     /** Have we checked if there is a backup on the server which we can use */
     private checkedForBackup = false;
+
+    /**
+     * The latest backup version on the server, when we last checked.
+     *
+     * If there was no backup on the server, `null`. If our attempt to check resulted in an error, `undefined`.
+     *
+     * Note that the backup was not necessarily verified.
+     */
+    private serverBackupInfo: KeyBackupInfo | null | undefined = undefined;
+
     private activeBackupVersion: string | null = null;
     private stopped = false;
 
@@ -89,6 +99,21 @@ export class RustBackupManager extends TypedEventEmitter<RustBackupCryptoEvents,
         return this.activeBackupVersion;
     }
 
+    /**
+     * Return the details of the latest backup on the server, when we last checked.
+     *
+     * This normally returns a cached value, but if we haven't yet made a request to the server, it will fire one off.
+     * It will always return the details of the active backup if key backup is enabled.
+     *
+     * If there was no backup on the server, `null`. If our attempt to check resulted in an error, `undefined`.
+     */
+    public async getServerBackupInfo(): Promise<KeyBackupInfo | null | undefined> {
+        // Do a validity check if we haven't already done one. The check is likely to fail if we don't yet have the
+        // backup keys -- but as a side-effect, it will populate `serverBackupInfo`.
+        await this.checkKeyBackupAndEnable(false);
+        return this.serverBackupInfo;
+    }
+
     /**
      * Determine if a key backup can be trusted.
      *
@@ -242,18 +267,21 @@ export class RustBackupManager extends TypedEventEmitter<RustBackupCryptoEvents,
     /** Helper for `checkKeyBackup` */
     private async doCheckKeyBackup(): Promise<KeyBackupCheck | null> {
         logger.log("Checking key backup status...");
-        let backupInfo: KeyBackupInfo | null = null;
+        let backupInfo: KeyBackupInfo | null | undefined;
         try {
             backupInfo = await this.requestKeyBackupVersion();
         } catch (e) {
             logger.warn("Error checking for active key backup", e);
+            this.serverBackupInfo = undefined;
             return null;
         }
         this.checkedForBackup = true;
 
         if (backupInfo && !backupInfo.version) {
             logger.warn("active backup lacks a useful 'version'; ignoring it");
+            backupInfo = undefined;
         }
+        this.serverBackupInfo = backupInfo;
 
         const activeVersion = await this.getActiveBackupVersion();
 
@@ -462,12 +490,13 @@ export class RustBackupManager extends TypedEventEmitter<RustBackupCryptoEvents,
         }
         return count;
     }
+
     /**
      * Get information about the current key backup from the server
      *
      * @returns Information object from API or null if there is no active backup.
      */
-    public async requestKeyBackupVersion(): Promise<KeyBackupInfo | null> {
+    private async requestKeyBackupVersion(): Promise<KeyBackupInfo | null> {
         return await requestKeyBackupVersion(this.http);
     }
 

src/rust-crypto/libolm_migration.ts

@@ -27,6 +27,7 @@ import { CrossSigningKeyInfo, Curve25519AuthData } from "../crypto-api";
 import { RustCrypto } from "./rust-crypto";
 import { KeyBackupInfo } from "../crypto-api/keybackup";
 import { sleep } from "../utils";
+import { encodeBase64 } from "../base64";
 
 /**
  * Determine if any data needs migrating from the legacy store, and do so.
@@ -400,19 +401,20 @@ async function getAndDecryptCachedSecretKey(
     legacyPickleKey: Uint8Array,
     name: string,
 ): Promise<string | undefined> {
-    let encodedKey: IEncryptedPayload | null = null;
-
-    await legacyStore.doTxn("readonly", "account", (txn) => {
-        legacyStore.getSecretStorePrivateKey(
-            txn,
-            (k) => {
-                encodedKey = k as IEncryptedPayload | null;
-            },
-            name as keyof SecretStorePrivateKeys,
-        );
+    const key = await new Promise<any>((resolve) => {
+        legacyStore.doTxn("readonly", [IndexedDBCryptoStore.STORE_ACCOUNT], (txn) => {
+            legacyStore.getSecretStorePrivateKey(txn, resolve, name as keyof SecretStorePrivateKeys);
+        });
     });
 
-    return encodedKey === null ? undefined : await decryptAES(encodedKey, legacyPickleKey, name);
+    if (key && key.ciphertext && key.iv && key.mac) {
+        return await decryptAES(key as IEncryptedPayload, legacyPickleKey, name);
+    } else if (key instanceof Uint8Array) {
+        // This is a legacy backward compatibility case where the key was stored in clear.
+        return encodeBase64(key);
+    } else {
+        return undefined;
+    }
 }
 
 /**

src/rust-crypto/rust-crypto.ts

@@ -18,6 +18,7 @@ import anotherjson from "another-json";
 import * as RustSdkCryptoJs from "@matrix-org/matrix-sdk-crypto-wasm";
 
 import type { IEventDecryptionResult, IMegolmSessionData } from "../@types/crypto";
+import { KnownMembership } from "../@types/membership";
 import type { IDeviceLists, IToDeviceEvent } from "../sync-accumulator";
 import type { IEncryptedEventInfo } from "../crypto/api";
 import { IContent, MatrixEvent, MatrixEventEvent } from "../models/event";
@@ -610,15 +611,17 @@ export class RustCrypto extends TypedEventEmitter<RustCryptoEvents, RustCryptoEv
      * Implementation of {@link CryptoApi#isCrossSigningReady}
      */
     public async isCrossSigningReady(): Promise<boolean> {
-        const { publicKeysOnDevice, privateKeysInSecretStorage, privateKeysCachedLocally } =
-            await this.getCrossSigningStatus();
+        const { privateKeysInSecretStorage, privateKeysCachedLocally } = await this.getCrossSigningStatus();
         const hasKeysInCache =
             Boolean(privateKeysCachedLocally.masterKey) &&
             Boolean(privateKeysCachedLocally.selfSigningKey) &&
             Boolean(privateKeysCachedLocally.userSigningKey);
 
-        // The cross signing is ready if the public and private keys are available
-        return publicKeysOnDevice && (hasKeysInCache || privateKeysInSecretStorage);
+        const identity = await this.getOwnIdentity();
+
+        // Cross-signing is ready if the public identity is trusted, and the private keys
+        // are either cached, or accessible via secret-storage.
+        return !!identity?.isVerified() && (hasKeysInCache || privateKeysInSecretStorage);
     }
 
     /**
@@ -1707,7 +1710,7 @@ class EventDecryptor {
             };
         } catch (err) {
             if (err instanceof RustSdkCryptoJs.MegolmDecryptionError) {
-                this.onMegolmDecryptionError(event, err);
+                this.onMegolmDecryptionError(event, err, await this.perSessionBackupDownloader.getServerBackupInfo());
             } else {
                 throw new DecryptionError(DecryptionFailureCode.UNKNOWN_ERROR, "Unknown error");
             }
@@ -1718,9 +1721,19 @@ class EventDecryptor {
      * Handle a `MegolmDecryptionError` returned by the rust SDK.
      *
      * Fires off a request to the `perSessionBackupDownloader`, if appropriate, and then throws a `DecryptionError`.
+     *
+     * @param event - The event which could not be decrypted.
+     * @param err - The error from the Rust SDK.
+     * @param serverBackupInfo - Details about the current backup from the server. `null` if there is no backup.
+     *     `undefined` if our attempt to check failed.
      */
-    private onMegolmDecryptionError(event: MatrixEvent, err: RustSdkCryptoJs.MegolmDecryptionError): never {
+    private onMegolmDecryptionError(
+        event: MatrixEvent,
+        err: RustSdkCryptoJs.MegolmDecryptionError,
+        serverBackupInfo: KeyBackupInfo | null | undefined,
+    ): never {
         const content = event.getWireContent();
+        const errorDetails = { session: content.sender_key + "|" + content.session_id };
 
         // If the error looks like it might be recoverable from backup, queue up a request to try that.
         if (
@@ -1728,9 +1741,42 @@ class EventDecryptor {
             err.code === RustSdkCryptoJs.DecryptionErrorCode.UnknownMessageIndex
         ) {
             this.perSessionBackupDownloader.onDecryptionKeyMissingError(event.getRoomId()!, content.session_id!);
+
+            // If the server is telling us our membership at the time the event
+            // was sent, and it isn't "join", we use a different error code.
+            const membership = event.getMembershipAtEvent();
+            if (membership && membership !== KnownMembership.Join && membership !== KnownMembership.Invite) {
+                throw new DecryptionError(
+                    DecryptionFailureCode.HISTORICAL_MESSAGE_USER_NOT_JOINED,
+                    "This message was sent when we were not a member of the room.",
+                    errorDetails,
+                );
+            }
+
+            // If the event was sent before this device was created, we use some different error codes.
+            if (event.getTs() <= this.olmMachine.deviceCreationTimeMs) {
+                if (serverBackupInfo === null) {
+                    throw new DecryptionError(
+                        DecryptionFailureCode.HISTORICAL_MESSAGE_NO_KEY_BACKUP,
+                        "This message was sent before this device logged in, and there is no key backup on the server.",
+                        errorDetails,
+                    );
+                } else if (!this.perSessionBackupDownloader.isKeyBackupDownloadConfigured()) {
+                    throw new DecryptionError(
+                        DecryptionFailureCode.HISTORICAL_MESSAGE_BACKUP_UNCONFIGURED,
+                        "This message was sent before this device logged in, and key backup is not working.",
+                        errorDetails,
+                    );
+                } else {
+                    throw new DecryptionError(
+                        DecryptionFailureCode.HISTORICAL_MESSAGE_WORKING_BACKUP,
+                        "This message was sent before this device logged in. Key backup is working, but we still do not (yet) have the key.",
+                        errorDetails,
+                    );
+                }
+            }
         }
 
-        const errorDetails = { session: content.sender_key + "|" + content.session_id };
         switch (err.code) {
             case RustSdkCryptoJs.DecryptionErrorCode.MissingRoomKey:
                 throw new DecryptionError(

src/rust-crypto/verification.ts

@@ -567,8 +567,10 @@ export class RustQrCodeVerifier extends BaseRustVerifer<RustSdkCryptoJs.Qr> impl
         // application to prompt the user to confirm their side.
         if (this.callbacks === null && this.inner.hasBeenScanned()) {
             this.callbacks = {
-                confirm: () => this.confirmScanning(),
-                cancel: () => this.cancel(),
+                confirm: (): void => {
+                    this.confirmScanning();
+                },
+                cancel: (): void => this.cancel(),
             };
         }