Clean up megolm-backup integ test (#3631)

* Add `CryptoApi.setDeviceVerified`

I need a way to mark devices as trusted for the backup tests.

* More tests

* Simplify E2EKeyResponder.addDeviceKeys

The user and device IDs are in the test data, so no need to pass them in

* Clean up key backup integration test

Make it use the CryptoApi rather than legacy `MatrixClient.crypto`, and use a
pre-signed backup instead of requiring a "blindlySignAnything" method.

* run megolm-backup tests on both crypto stacks

* avoid internal backupManager

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

@@ -15,17 +15,16 @@ limitations under the License.
 */
 
 import fetchMock from "fetch-mock-jest";
+import "fake-indexeddb/auto";
 
-import { logger } from "../../../src/logger";
+import { IKeyBackupSession } from "../../../src/crypto/keybackup";
-import { decodeRecoveryKey } from "../../../src/crypto/recoverykey";
-import { IKeyBackupInfo, IKeyBackupSession } from "../../../src/crypto/keybackup";
 import { createClient, ICreateClientOpts, IEvent, MatrixClient } from "../../../src";
-import { MatrixEventEvent } from "../../../src/models/event";
 import { SyncResponder } from "../../test-utils/SyncResponder";
 import { E2EKeyReceiver } from "../../test-utils/E2EKeyReceiver";
 import { E2EKeyResponder } from "../../test-utils/E2EKeyResponder";
 import { mockInitialApiRequests } from "../../test-utils/mockEndpoints";
-import { syncPromise } from "../../test-utils/test-utils";
+import { awaitDecryption, CRYPTO_BACKENDS, InitCrypto, syncPromise } from "../../test-utils/test-utils";
+import * as testData from "../../test-utils/test-data";
 
 const ROOM_ID = "!ROOM:ID";
 
@@ -72,22 +71,14 @@ const CURVE25519_KEY_BACKUP_DATA: IKeyBackupSession = {
     },
 };
 
-const CURVE25519_BACKUP_INFO: IKeyBackupInfo = {
-    algorithm: "m.megolm_backup.v1.curve25519-aes-sha2",
-    version: "1",
-    auth_data: {
-        public_key: "hSDwCYkwp1R0i33ctD73Wg2/Og0mOBr066SpjqqbTmo",
-        // Will be updated with correct value on the fly
-        signatures: {},
-    },
-};
-
-const RECOVERY_KEY = "EsTc LW2K PGiF wKEA 3As5 g5c4 BXwk qeeJ ZJV8 Q9fu gUMN UE4d";
-
 const TEST_USER_ID = "@alice:localhost";
 const TEST_DEVICE_ID = "xzcvb";
 
-describe("megolm key backups", function () {
+describe.each(Object.entries(CRYPTO_BACKENDS))("megolm-keys backup (%s)", (backend: string, initCrypto: InitCrypto) => {
+    // oldBackendOnly is an alternative to `it` or `test` which will skip the test if we are running against the
+    // Rust backend. Once we have full support in the rust sdk, it will go away.
+    const oldBackendOnly = backend === "rust-sdk" ? test.skip : test;
+
     let aliceClient: MatrixClient;
     /** an object which intercepts `/sync` requests on the test homeserver */
     let syncResponder: SyncResponder;
@@ -108,6 +99,7 @@ describe("megolm key backups", function () {
         syncResponder = new SyncResponder(TEST_HOMESERVER_URL);
         e2eKeyReceiver = new E2EKeyReceiver(TEST_HOMESERVER_URL);
         e2eKeyResponder = new E2EKeyResponder(TEST_HOMESERVER_URL);
+        e2eKeyResponder.addDeviceKeys(testData.SIGNED_TEST_DEVICE_DATA);
         e2eKeyResponder.addKeyReceiver(TEST_USER_ID, e2eKeyReceiver);
     });
 
@@ -130,12 +122,12 @@ describe("megolm key backups", function () {
             deviceId: TEST_DEVICE_ID,
             ...opts,
         });
-        await client.initCrypto();
+        await initCrypto(client);
 
         return client;
     }
 
-    it("Alice checks key backups when receiving a message she can't decrypt", async function () {
+    oldBackendOnly("Alice checks key backups when receiving a message she can't decrypt", async function () {
         const syncResponse = {
             next_batch: 1,
             rooms: {
@@ -150,35 +142,32 @@ describe("megolm key backups", function () {
         };
 
         fetchMock.get("express:/_matrix/client/v3/room_keys/keys/:room_id/:session_id", CURVE25519_KEY_BACKUP_DATA);
-
+        fetchMock.get("path:/_matrix/client/v3/room_keys/version", testData.SIGNED_BACKUP_DATA);
-        // mock for the outgoing key requests that will be sent
-        fetchMock.put("express:/_matrix/client/r0/sendToDevice/m.room_key_request/:txid", {});
-
-        // We'll need to add a signature to the backup data, so take a copy to avoid mutating global state.
-        const backupData = JSON.parse(JSON.stringify(CURVE25519_BACKUP_INFO));
-        fetchMock.get("path:/_matrix/client/v3/room_keys/version", backupData);
 
         aliceClient = await initTestClient();
-        await aliceClient.crypto!.signObject(backupData.auth_data);
+        const aliceCrypto = aliceClient.getCrypto()!;
-        await aliceClient.crypto!.storeSessionBackupPrivateKey(decodeRecoveryKey(RECOVERY_KEY));
+        await aliceCrypto.storeSessionBackupPrivateKey(Buffer.from(testData.BACKUP_DECRYPTION_KEY_BASE64, "base64"));
-        await aliceClient.crypto!.backupManager!.checkAndStart();
 
         // start after saving the private key
         await aliceClient.startClient();
 
+        // Persuade alice to fetch the device list. Completing the initial sync will make the device list download
+        // outdated device lists (of which our own user will be one).
+        syncResponder.sendOrQueueSyncResponse({});
+        await jest.advanceTimersByTimeAsync(10); // DeviceList has a sleep(5) which we need to make happen
+
+        // tell Alice to trust the dummy device that signed the backup, and re-check the backup.
+        // XXX: should we automatically re-check after a device becomes verified?
+        await aliceCrypto.setDeviceVerified(testData.TEST_USER_ID, testData.TEST_DEVICE_ID);
+        await aliceClient.checkKeyBackup();
+
+        // Now, send Alice a message that she won't be able to decrypt, and check that she fetches the key from the backup.
         syncResponder.sendOrQueueSyncResponse(syncResponse);
         await syncPromise(aliceClient);
 
         const room = aliceClient.getRoom(ROOM_ID)!;
-
         const event = room.getLiveTimeline().getEvents()[0];
-        await new Promise((resolve, reject) => {
+        await awaitDecryption(event, { waitOnDecryptionFailure: true });
-            event.once(MatrixEventEvent.Decrypted, (ev) => {
-                logger.log(`${Date.now()} event ${event.getId()} now decrypted`);
-                resolve(ev);
-            });
-        });
-
         expect(event.getContent()).toEqual("testytest");
     });
 });

spec/integ/crypto/verification.spec.ts

@@ -124,7 +124,7 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("verification (%s)", (backend: st
     describe("Outgoing verification requests for another device", () => {
         beforeEach(async () => {
             // pretend that we have another device, which we will verify
-            e2eKeyResponder.addDeviceKeys(TEST_USER_ID, TEST_DEVICE_ID, SIGNED_TEST_DEVICE_DATA);
+            e2eKeyResponder.addDeviceKeys(SIGNED_TEST_DEVICE_DATA);
         });
 
         // test with (1) the default verification method list, (2) a custom verification method list.
@@ -626,7 +626,7 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("verification (%s)", (backend: st
     describe("cancellation", () => {
         beforeEach(async () => {
             // pretend that we have another device, which we will start verifying
-            e2eKeyResponder.addDeviceKeys(TEST_USER_ID, TEST_DEVICE_ID, SIGNED_TEST_DEVICE_DATA);
+            e2eKeyResponder.addDeviceKeys(SIGNED_TEST_DEVICE_DATA);
             e2eKeyResponder.addCrossSigningData(SIGNED_CROSS_SIGNING_KEYS_DATA);
 
             aliceClient = await startTestClient();
@@ -743,7 +743,7 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("verification (%s)", (backend: st
 
     describe("Incoming verification from another device", () => {
         beforeEach(async () => {
-            e2eKeyResponder.addDeviceKeys(TEST_USER_ID, TEST_DEVICE_ID, SIGNED_TEST_DEVICE_DATA);
+            e2eKeyResponder.addDeviceKeys(SIGNED_TEST_DEVICE_DATA);
 
             aliceClient = await startTestClient();
             await waitForDeviceList();

spec/test-utils/E2EKeyResponder.ts

@@ -89,12 +89,10 @@ export class E2EKeyResponder {
     /**
      * Add a set of device keys for return by a future `/keys/query`, as if they had been `/upload`ed
      *
-     * @param userId - user the keys belong to
-     * @param deviceId - device the keys belong to
      * @param keys - device keys for this device.
      */
-    public addDeviceKeys(userId: string, deviceId: string, keys: IDeviceKeys) {
+    public addDeviceKeys(keys: IDeviceKeys) {
-        this.deviceKeysByUserByDevice.getOrCreate(userId).set(deviceId, keys);
+        this.deviceKeysByUserByDevice.getOrCreate(keys.user_id).set(keys.device_id, keys);
     }
 
     /** Add a set of cross-signing keys for return by a future `/keys/query`, as if they had been `/keys/device_signing/upload`ed

spec/test-utils/test-data/generate-test-data.py

@@ -28,7 +28,7 @@ import base64
 import json
 
 from canonicaljson import encode_canonical_json
-from cryptography.hazmat.primitives.asymmetric import ed25519
+from cryptography.hazmat.primitives.asymmetric import ed25519, x25519
 from cryptography.hazmat.primitives.serialization import Encoding, PublicFormat
 
 # input data
@@ -41,6 +41,8 @@ MASTER_CROSS_SIGNING_PRIVATE_KEY_BYTES = b"doyouspeakwhaaaaaaaaaaaaaaaaaale"
 USER_CROSS_SIGNING_PRIVATE_KEY_BYTES = b"useruseruseruseruseruseruseruser"
 SELF_CROSS_SIGNING_PRIVATE_KEY_BYTES = b"selfselfselfselfselfselfselfself"
 
+# Private key for secure key backup. There are some sessions encrypted with this key in megolm-backup.spec.ts
+B64_BACKUP_DECRYPTION_KEY = "dwdtCnMYpX08FsFyUbJmRd9ML4frwJkqsXf7pR25LCo="
 
 def main() -> None:
     private_key = ed25519.Ed25519PrivateKey.from_private_bytes(
@@ -71,29 +73,47 @@ def main() -> None:
     b64_master_public_key = encode_base64(
         master_private_key.public_key().public_bytes(Encoding.Raw, PublicFormat.Raw)
     )
-    b64_master_private_key = encode_base64(
+    b64_master_private_key = encode_base64(MASTER_CROSS_SIGNING_PRIVATE_KEY_BYTES)
-        MASTER_CROSS_SIGNING_PRIVATE_KEY_BYTES
-    )
 
     self_signing_private_key = ed25519.Ed25519PrivateKey.from_private_bytes(
         SELF_CROSS_SIGNING_PRIVATE_KEY_BYTES
     )
     b64_self_signing_public_key = encode_base64(
-        self_signing_private_key.public_key().public_bytes(Encoding.Raw, PublicFormat.Raw)
+        self_signing_private_key.public_key().public_bytes(
-    )
+            Encoding.Raw, PublicFormat.Raw
-    b64_self_signing_private_key = encode_base64(
+        )
-        SELF_CROSS_SIGNING_PRIVATE_KEY_BYTES
     )
+    b64_self_signing_private_key = encode_base64(SELF_CROSS_SIGNING_PRIVATE_KEY_BYTES)
 
     user_signing_private_key = ed25519.Ed25519PrivateKey.from_private_bytes(
         USER_CROSS_SIGNING_PRIVATE_KEY_BYTES
     )
     b64_user_signing_public_key = encode_base64(
-        user_signing_private_key.public_key().public_bytes(Encoding.Raw, PublicFormat.Raw)
+        user_signing_private_key.public_key().public_bytes(
+            Encoding.Raw, PublicFormat.Raw
+        )
     )
-    b64_user_signing_private_key = encode_base64(
+    b64_user_signing_private_key = encode_base64(USER_CROSS_SIGNING_PRIVATE_KEY_BYTES)
-        USER_CROSS_SIGNING_PRIVATE_KEY_BYTES
+
+    backup_decryption_key = x25519.X25519PrivateKey.from_private_bytes(
+        base64.b64decode(B64_BACKUP_DECRYPTION_KEY)
     )
+    b64_backup_public_key = encode_base64(
+        backup_decryption_key.public_key().public_bytes(Encoding.Raw, PublicFormat.Raw)
+    )
+
+    backup_data = {
+        "algorithm": "m.megolm_backup.v1.curve25519-aes-sha2",
+        "version": "1",
+        "auth_data": {
+            "public_key": b64_backup_public_key,
+        },
+    }
+    # sign with our device key
+    sig = sign_json(backup_data["auth_data"], private_key)
+    backup_data["auth_data"]["signatures"] = {
+        TEST_USER_ID: {f"ed25519:{TEST_DEVICE_ID}": sig}
+    }
 
     print(
         f"""\
@@ -104,6 +124,7 @@ def main() -> None:
 
 import {{ IDeviceKeys }} from "../../../src/@types/crypto";
 import {{ IDownloadKeyResult }} from "../../../src";
+import {{ KeyBackupInfo }} from "../../../src/crypto-api";
 
 /* eslint-disable comma-dangle */
 
@@ -138,6 +159,12 @@ export const USER_CROSS_SIGNING_PRIVATE_KEY_BASE64 = "{b64_user_signing_private_
 export const SIGNED_CROSS_SIGNING_KEYS_DATA: Partial<IDownloadKeyResult> = {
         json.dumps(build_cross_signing_keys_data(), indent=4)
 };
+
+/** base64-encoded backup decryption (private) key */
+export const BACKUP_DECRYPTION_KEY_BASE64 = "{ B64_BACKUP_DECRYPTION_KEY }";
+
+/** Signed backup data, suitable for return from `GET /_matrix/client/v3/room_keys/keys/{{roomId}}/{{sessionId}}` */
+export const SIGNED_BACKUP_DATA: KeyBackupInfo = { json.dumps(backup_data, indent=4) };
 """,
         end="",
     )

spec/test-utils/test-data/index.ts

@@ -5,6 +5,7 @@
 
 import { IDeviceKeys } from "../../../src/@types/crypto";
 import { IDownloadKeyResult } from "../../../src";
+import { KeyBackupInfo } from "../../../src/crypto-api";
 
 /* eslint-disable comma-dangle */
 
@@ -97,3 +98,20 @@ export const SIGNED_CROSS_SIGNING_KEYS_DATA: Partial<IDownloadKeyResult> = {
         }
     }
 };
+
+/** base64-encoded backup decryption (private) key */
+export const BACKUP_DECRYPTION_KEY_BASE64 = "dwdtCnMYpX08FsFyUbJmRd9ML4frwJkqsXf7pR25LCo=";
+
+/** Signed backup data, suitable for return from `GET /_matrix/client/v3/room_keys/keys/{roomId}/{sessionId}` */
+export const SIGNED_BACKUP_DATA: KeyBackupInfo = {
+    "algorithm": "m.megolm_backup.v1.curve25519-aes-sha2",
+    "version": "1",
+    "auth_data": {
+        "public_key": "hSDwCYkwp1R0i33ctD73Wg2/Og0mOBr066SpjqqbTmo",
+        "signatures": {
+            "@alice:localhost": {
+                "ed25519:test_device": "KDSNeumirTsd8piI0oVfv/wzg4J4HlEc7rs5XhODFcJ/YAcUdg65ajsZG+rLI0TQOSSGjorJqcrSiSB1HRSCAA"
+            }
+        }
+    }
+};