Introduce a mechanism for using the rust-crypto-sdk

package.json

@@ -54,6 +54,7 @@
     ],
     "dependencies": {
         "@babel/runtime": "^7.12.5",
+        "@matrix-org/matrix-sdk-crypto-js": "^0.1.0-alpha.1",
         "another-json": "^0.2.0",
         "bs58": "^5.0.0",
         "content-type": "^1.0.4",

spec/integ/rust-crypto.spec.ts

@@ -0,0 +1,90 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import "fake-indexeddb/auto";
+import { IDBFactory } from "fake-indexeddb";
+
+import { createClient } from "../../src";
+
+afterEach(() => {
+    // reset fake-indexeddb after each test, to make sure we don't leak connections
+    // cf https://github.com/dumbmatter/fakeIndexedDB#wipingresetting-the-indexeddb-for-a-fresh-state
+    // eslint-disable-next-line no-global-assign
+    indexedDB = new IDBFactory();
+});
+
+describe("MatrixClient.initRustCrypto", () => {
+    it("should raise if userId or deviceId is unknown", async () => {
+        const unknownUserClient = createClient({
+            baseUrl: "http://test.server",
+            deviceId: "aliceDevice",
+        });
+        await expect(() => unknownUserClient.initRustCrypto()).rejects.toThrow("unknown userId");
+
+        const unknownDeviceClient = createClient({
+            baseUrl: "http://test.server",
+            userId: "@alice:test",
+        });
+        await expect(() => unknownDeviceClient.initRustCrypto()).rejects.toThrow("unknown deviceId");
+    });
+
+    it("should create the indexed dbs", async () => {
+        const matrixClient = createClient({
+            baseUrl: "http://test.server",
+            userId: "@alice:localhost",
+            deviceId: "aliceDevice",
+        });
+
+        // No databases.
+        expect(await indexedDB.databases()).toHaveLength(0);
+
+        await matrixClient.initRustCrypto();
+
+        // should have two dbs now
+        const databaseNames = (await indexedDB.databases()).map((db) => db.name);
+        expect(databaseNames).toEqual(
+            expect.arrayContaining(["matrix-js-sdk::matrix-sdk-crypto", "matrix-js-sdk::matrix-sdk-crypto-meta"]),
+        );
+    });
+
+    it("should ignore a second call", async () => {
+        const matrixClient = createClient({
+            baseUrl: "http://test.server",
+            userId: "@alice:localhost",
+            deviceId: "aliceDevice",
+        });
+
+        await matrixClient.initRustCrypto();
+        await matrixClient.initRustCrypto();
+    });
+});
+
+describe("MatrixClient.clearStores", () => {
+    it("should clear the indexeddbs", async () => {
+        const matrixClient = createClient({
+            baseUrl: "http://test.server",
+            userId: "@alice:localhost",
+            deviceId: "aliceDevice",
+        });
+
+        await matrixClient.initRustCrypto();
+        expect(await indexedDB.databases()).toHaveLength(2);
+        await matrixClient.stopClient();
+
+        await matrixClient.clearStores();
+        expect(await indexedDB.databases()).toHaveLength(0);
+    });
+});

src/client.ts

@@ -1657,6 +1657,38 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         if (this.cryptoStore) {
             promises.push(this.cryptoStore.deleteAllData());
         }
+
+        // delete the stores used by the rust matrix-sdk-crypto, in case they were used
+        const deleteRustSdkStore = async (): Promise<void> => {
+            let indexedDB: IDBFactory;
+            try {
+                indexedDB = global.indexedDB;
+            } catch (e) {
+                // No indexeddb support
+                return;
+            }
+            for (const dbname of ["matrix-js-sdk::matrix-sdk-crypto", "matrix-js-sdk::matrix-sdk-crypto-meta"]) {
+                const prom = new Promise((resolve, reject) => {
+                    logger.info(`Removing IndexedDB instance ${dbname}`);
+                    const req = indexedDB.deleteDatabase(dbname);
+                    req.onsuccess = (_): void => {
+                        logger.info(`Removed IndexedDB instance ${dbname}`);
+                        resolve(0);
+                    };
+                    req.onerror = (e): void => {
+                        logger.error(`Failed to remove IndexedDB instance ${dbname}: ${e}`);
+                        reject(new Error(`Error clearing storage: ${e}`));
+                    };
+                    req.onblocked = (e): void => {
+                        logger.info(`cannot yet remove IndexedDB instance ${dbname}`);
+                        //reject(new Error(`Error clearing storage: ${e}`));
+                    };
+                });
+                await prom;
+            }
+        };
+        promises.push(deleteRustSdkStore());
+
         return Promise.all(promises).then(); // .then to fix types
     }
 
@@ -2051,6 +2083,44 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         });
     }
 
+    /**
+     * Initialise support for end-to-end encryption in this client, using the rust matrix-sdk-crypto.
+     *
+     * An alternative to {@link initCrypto}.
+     *
+     * *WARNING*: this API is very experimental and should not yet be used in production code! Eventually
+     *    it will be deprecated and `initCrypto` will do the same thing.
+     *
+     * @returns a Promise which will resolve when the crypto layer has been
+     *    successfully initialised.
+     */
+    public async initRustCrypto(): Promise<void> {
+        if (this.cryptoBackend) {
+            logger.warn("Attempt to re-initialise e2e encryption on MatrixClient");
+            return;
+        }
+
+        const userId = this.getUserId();
+        if (userId === null) {
+            throw new Error(
+                `Cannot enable encryption on MatrixClient with unknown userId: ` +
+                    `ensure userId is passed in createClient().`,
+            );
+        }
+        const deviceId = this.getDeviceId();
+        if (deviceId === null) {
+            throw new Error(
+                `Cannot enable encryption on MatrixClient with unknown deviceId: ` +
+                    `ensure deviceId is passed in createClient().`,
+            );
+        }
+
+        // importing rust-crypto will download the webassembly, so we delay it until we know it will be
+        // needed.
+        const RustCrypto = await import("./rust-crypto");
+        this.cryptoBackend = await RustCrypto.initRustCrypto(userId, deviceId);
+    }
+
     /**
      * Is end-to-end crypto enabled for this client.
      * @returns True if end-to-end is enabled.

src/rust-crypto/index.ts

@@ -0,0 +1,40 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import * as RustSdkCryptoJs from "@matrix-org/matrix-sdk-crypto-js";
+
+import { RustCrypto } from "./rust-crypto";
+import { logger } from "../logger";
+import { CryptoBackend } from "../common-crypto/CryptoBackend";
+
+export async function initRustCrypto(userId: string, deviceId: string): Promise<CryptoBackend> {
+    // initialise the rust matrix-sdk-crypto-js, if it hasn't already been done
+    await RustSdkCryptoJs.initAsync();
+
+    // enable tracing in the rust-sdk
+    new RustSdkCryptoJs.Tracing(RustSdkCryptoJs.LoggerLevel.Debug).turnOn();
+
+    const u = new RustSdkCryptoJs.UserId(userId);
+    const d = new RustSdkCryptoJs.DeviceId(deviceId);
+    logger.info("Init OlmMachine");
+
+    // TODO: use the pickle key for the passphrase
+    const olmMachine = await RustSdkCryptoJs.OlmMachine.initialize(u, d, "matrix-js-sdk", "test pass");
+    const rustCrypto = new RustCrypto(olmMachine, userId, deviceId);
+
+    logger.info("Completed rust crypto-sdk setup");
+    return rustCrypto;
+}

src/rust-crypto/rust-crypto.ts

@@ -0,0 +1,60 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import * as RustSdkCryptoJs from "@matrix-org/matrix-sdk-crypto-js";
+
+import { IEventDecryptionResult } from "../@types/crypto";
+import { MatrixEvent } from "../models/event";
+import { CryptoBackend } from "../common-crypto/CryptoBackend";
+
+// import { logger } from "../logger";
+
+/**
+ * An implementation of {@link CryptoBackend} using the Rust matrix-sdk-crypto.
+ */
+export class RustCrypto implements CryptoBackend {
+    public globalBlacklistUnverifiedDevices = false;
+    public globalErrorOnUnknownDevices = false;
+
+    /** whether stop() has been called */
+    private stopped = false;
+
+    public constructor(private readonly olmMachine: RustSdkCryptoJs.OlmMachine, _userId: string, _deviceId: string) {}
+
+    public stop(): void {
+        // stop() may be called multiple times, but attempting to close() the OlmMachine twice
+        // will cause an error.
+        if (this.stopped) {
+            return;
+        }
+        this.stopped = true;
+
+        // make sure we close() the OlmMachine; doing so means that all the Rust objects will be
+        // cleaned up; in particular, the indexeddb connections will be closed, which means they
+        // can then be deleted.
+        this.olmMachine.close();
+    }
+
+    public async decryptEvent(event: MatrixEvent): Promise<IEventDecryptionResult> {
+        await this.olmMachine.decryptRoomEvent("event", new RustSdkCryptoJs.RoomId("room"));
+        throw new Error("not implemented");
+    }
+
+    public async userHasCrossSigningKeys(): Promise<boolean> {
+        // TODO
+        return false;
+    }
+}