Remove unused CryptoCallbacks implementations (#12919)

* Remove unused `onSecretRequested` callback

This thing is unused with the rust crypto stack (which is lucky, because it
uses methods that only work with the legacy stack).

* Remove unused `getDehydrationKey` method

This callback is no longer used, so there is no need for an implementation.

* Remove unused `dehydrationCache`

This is no longer written to, so is redundant.

* Remove another write to `CryptoCallbacks.getDehydrationKey`

As before: this hook is no longer used by the js-sdk, so writing to it is
pointless.

Author: richvdh

src/MatrixClientPeg.ts

@@ -41,7 +41,6 @@ import MatrixClientBackedSettingsHandler from "./settings/handlers/MatrixClientB
 import * as StorageManager from "./utils/StorageManager";
 import IdentityAuthClient from "./IdentityAuthClient";
 import { crossSigningCallbacks } from "./SecurityManager";
-import { ModuleRunner } from "./modules/ModuleRunner";
 import { SlidingSyncManager } from "./SlidingSyncManager";
 import { _t, UserFriendlyError } from "./languageHandler";
 import { SettingLevel } from "./settings/SettingLevel";
@@ -452,11 +451,6 @@ class MatrixClientPegClass implements IMatrixClientPeg {
             },
         };
 
-        const dehydrationKeyCallback = ModuleRunner.instance.extensions.cryptoSetup.getDehydrationKeyCallback();
-        if (dehydrationKeyCallback) {
-            opts.cryptoCallbacks!.getDehydrationKey = dehydrationKeyCallback;
-        }
-
         this.matrixClient = createMatrixClient(opts);
         this.matrixClient.setGuest(Boolean(creds.guest));
 

src/SecurityManager.ts

@@ -14,7 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import { Crypto, ICryptoCallbacks, encodeBase64, SecretStorage } from "matrix-js-sdk/src/matrix";
+import { ICryptoCallbacks, SecretStorage } from "matrix-js-sdk/src/matrix";
 import { deriveKey } from "matrix-js-sdk/src/crypto/key_passphrase";
 import { decodeRecoveryKey } from "matrix-js-sdk/src/crypto/recoverykey";
 import { logger } from "matrix-js-sdk/src/logger";
@@ -39,11 +39,6 @@ let secretStorageKeys: Record<string, Uint8Array> = {};
 let secretStorageKeyInfo: Record<string, SecretStorage.SecretStorageKeyDescription> = {};
 let secretStorageBeingAccessed = false;
 
-let dehydrationCache: {
-    key?: Uint8Array;
-    keyInfo?: SecretStorage.SecretStorageKeyDescription;
-} = {};
-
 /**
  * This can be used by other components to check if secret storage access is in
  * progress, so that we can e.g. avoid intermittently showing toasts during
@@ -119,14 +114,6 @@ async function getSecretStorageKey({
         return [keyId, secretStorageKeys[keyId]];
     }
 
-    if (dehydrationCache.key) {
-        if (await MatrixClientPeg.safeGet().checkSecretStorageKey(dehydrationCache.key, keyInfo)) {
-            logger.debug("getSecretStorageKey: returning key from dehydration cache");
-            cacheSecretStorageKey(keyId, keyInfo, dehydrationCache.key);
-            return [keyId, dehydrationCache.key];
-        }
-    }
-
     const keyFromCustomisations = ModuleRunner.instance.extensions.cryptoSetup.getSecretStorageKey();
     if (keyFromCustomisations) {
         logger.log("getSecretStorageKey: Using secret storage key from CryptoSetupExtension");
@@ -171,56 +158,6 @@ async function getSecretStorageKey({
     return [keyId, key];
 }
 
-export async function getDehydrationKey(
-    keyInfo: SecretStorage.SecretStorageKeyDescription,
-    checkFunc: (data: Uint8Array) => void,
-): Promise<Uint8Array> {
-    const keyFromCustomisations = ModuleRunner.instance.extensions.cryptoSetup.getSecretStorageKey();
-    if (keyFromCustomisations) {
-        logger.log("CryptoSetupExtension: Using key from extension (dehydration)");
-        return keyFromCustomisations;
-    }
-
-    const inputToKey = makeInputToKey(keyInfo);
-    const { finished } = Modal.createDialog(
-        AccessSecretStorageDialog,
-        /* props= */
-        {
-            keyInfo,
-            checkPrivateKey: async (input: KeyParams): Promise<boolean> => {
-                const key = await inputToKey(input);
-                try {
-                    checkFunc(key);
-                    return true;
-                } catch (e) {
-                    return false;
-                }
-            },
-        },
-        /* className= */ undefined,
-        /* isPriorityModal= */ false,
-        /* isStaticModal= */ false,
-        /* options= */ {
-            onBeforeClose: async (reason): Promise<boolean> => {
-                if (reason === "backgroundClick") {
-                    return confirmToDismiss();
-                }
-                return true;
-            },
-        },
-    );
-    const [input] = await finished;
-    if (!input) {
-        throw new AccessCancelledError();
-    }
-    const key = await inputToKey(input);
-
-    // need to copy the key because rehydration (unpickling) will clobber it
-    dehydrationCache = { key: new Uint8Array(key), keyInfo };
-
-    return key;
-}
-
 function cacheSecretStorageKey(
     keyId: string,
     keyInfo: SecretStorage.SecretStorageKeyDescription,
@@ -232,50 +169,9 @@ function cacheSecretStorageKey(
     }
 }
 
-async function onSecretRequested(
-    userId: string,
-    deviceId: string,
-    requestId: string,
-    name: string,
-    deviceTrust: Crypto.DeviceVerificationStatus,
-): Promise<string | undefined> {
-    logger.log("onSecretRequested", userId, deviceId, requestId, name, deviceTrust);
-    const client = MatrixClientPeg.safeGet();
-    if (userId !== client.getUserId()) {
-        return;
-    }
-    if (!deviceTrust?.isVerified()) {
-        logger.log(`Ignoring secret request from untrusted device ${deviceId}`);
-        return;
-    }
-    if (
-        name === "m.cross_signing.master" ||
-        name === "m.cross_signing.self_signing" ||
-        name === "m.cross_signing.user_signing"
-    ) {
-        const callbacks = client.getCrossSigningCacheCallbacks();
-        if (!callbacks?.getCrossSigningKeyCache) return;
-        const keyId = name.replace("m.cross_signing.", "");
-        const key = await callbacks.getCrossSigningKeyCache(keyId);
-        if (!key) {
-            logger.log(`${keyId} requested by ${deviceId}, but not found in cache`);
-        }
-        return key ? encodeBase64(key) : undefined;
-    } else if (name === "m.megolm_backup.v1") {
-        const key = await client.crypto?.getSessionBackupPrivateKey();
-        if (!key) {
-            logger.log(`session backup key requested by ${deviceId}, but not found in cache`);
-        }
-        return key ? encodeBase64(key) : undefined;
-    }
-    logger.warn("onSecretRequested didn't recognise the secret named ", name);
-}
-
 export const crossSigningCallbacks: ICryptoCallbacks = {
     getSecretStorageKey,
     cacheSecretStorageKey,
-    onSecretRequested,
-    getDehydrationKey,
 };
 
 /**

test/MatrixClientPeg-test.ts

@@ -16,16 +16,11 @@ limitations under the License.
 
 import { logger } from "matrix-js-sdk/src/logger";
 import fetchMockJest from "fetch-mock-jest";
-import {
-    ProvideCryptoSetupExtensions,
-    SecretStorageKeyDescription,
-} from "@matrix-org/react-sdk-module-api/lib/lifecycles/CryptoSetupExtensions";
 
 import { advanceDateAndTime, stubClient } from "./test-utils";
 import { IMatrixClientPeg, MatrixClientPeg as peg } from "../src/MatrixClientPeg";
 import SettingsStore from "../src/settings/SettingsStore";
 import { SettingLevel } from "../src/settings/SettingLevel";
-import { ModuleRunner } from "../src/modules/ModuleRunner";
 
 jest.useFakeTimers();
 
@@ -78,78 +73,6 @@ describe("MatrixClientPeg", () => {
         expect(peg.userRegisteredWithinLastHours(24)).toBe(false);
     });
 
-    describe(".start extensions", () => {
-        let testPeg: IMatrixClientPeg;
-
-        beforeEach(() => {
-            // instantiate a MatrixClientPegClass instance, with a new MatrixClient
-            testPeg = new PegClass();
-            fetchMockJest.get("http://example.com/_matrix/client/versions", {});
-        });
-
-        describe("cryptoSetup extension", () => {
-            it("should call default cryptoSetup.getDehydrationKeyCallback", async () => {
-                const mockCryptoSetup = {
-                    SHOW_ENCRYPTION_SETUP_UI: true,
-                    examineLoginResponse: jest.fn(),
-                    persistCredentials: jest.fn(),
-                    getSecretStorageKey: jest.fn(),
-                    createSecretStorageKey: jest.fn(),
-                    catchAccessSecretStorageError: jest.fn(),
-                    setupEncryptionNeeded: jest.fn(),
-                    getDehydrationKeyCallback: jest.fn().mockReturnValue(null),
-                } as ProvideCryptoSetupExtensions;
-
-                // Ensure we have an instance before we set up spies
-                const instance = ModuleRunner.instance;
-                jest.spyOn(instance.extensions, "cryptoSetup", "get").mockReturnValue(mockCryptoSetup);
-
-                testPeg.replaceUsingCreds({
-                    accessToken: "SEKRET",
-                    homeserverUrl: "http://example.com",
-                    userId: "@user:example.com",
-                    deviceId: "TEST_DEVICE_ID",
-                });
-
-                expect(mockCryptoSetup.getDehydrationKeyCallback).toHaveBeenCalledTimes(1);
-            });
-
-            it("should call overridden cryptoSetup.getDehydrationKeyCallback", async () => {
-                const mockDehydrationKeyCallback = () => Uint8Array.from([0x11, 0x22, 0x33]);
-
-                const mockCryptoSetup = {
-                    SHOW_ENCRYPTION_SETUP_UI: true,
-                    examineLoginResponse: jest.fn(),
-                    persistCredentials: jest.fn(),
-                    getSecretStorageKey: jest.fn(),
-                    createSecretStorageKey: jest.fn(),
-                    catchAccessSecretStorageError: jest.fn(),
-                    setupEncryptionNeeded: jest.fn(),
-                    getDehydrationKeyCallback: jest.fn().mockReturnValue(mockDehydrationKeyCallback),
-                } as ProvideCryptoSetupExtensions;
-
-                // Ensure we have an instance before we set up spies
-                const instance = ModuleRunner.instance;
-                jest.spyOn(instance.extensions, "cryptoSetup", "get").mockReturnValue(mockCryptoSetup);
-
-                testPeg.replaceUsingCreds({
-                    accessToken: "SEKRET",
-                    homeserverUrl: "http://example.com",
-                    userId: "@user:example.com",
-                    deviceId: "TEST_DEVICE_ID",
-                });
-                expect(mockCryptoSetup.getDehydrationKeyCallback).toHaveBeenCalledTimes(1);
-
-                const client = testPeg.get();
-                const dehydrationKey = await client?.cryptoCallbacks.getDehydrationKey!(
-                    {} as SecretStorageKeyDescription,
-                    (key: Uint8Array) => true,
-                );
-                expect(dehydrationKey).toEqual(Uint8Array.from([0x11, 0x22, 0x33]));
-            });
-        });
-    });
-
     describe(".start", () => {
         let testPeg: IMatrixClientPeg;