Support for migration from from libolm (#3978)

* Use a `StoreHandle` to init OlmMachine

This will be faster if we need to prepare the store.

* Include "needsBackup" flag in inbound group session batches

* On startup, import data from libolm cryptostore

* ISessionExtended -> SessionExtended

.prettierignore

@@ -25,5 +25,6 @@ out
 # This file is owned, parsed, and generated by allchange, which doesn't comply with prettier
 /CHANGELOG.md
 
-# This file is also autogenerated
+# These files are also autogenerated
 /spec/test-utils/test-data/index.ts
+/spec/test-utils/test_indexeddb_cryptostore_dump/dump.json

spec/integ/crypto/rust-crypto.spec.ts

@@ -16,8 +16,12 @@ limitations under the License.
 
 import "fake-indexeddb/auto";
 import { IDBFactory } from "fake-indexeddb";
+import fetchMock from "fetch-mock-jest";
 
-import { createClient } from "../../../src";
+import { createClient, IndexedDBCryptoStore } from "../../../src";
+import { populateStore } from "../../test-utils/test_indexeddb_cryptostore_dump";
+
+jest.setTimeout(15000);
 
 afterEach(() => {
     // reset fake-indexeddb after each test, to make sure we don't leak connections
@@ -88,6 +92,47 @@ describe("MatrixClient.initRustCrypto", () => {
         await matrixClient.initRustCrypto();
         await matrixClient.initRustCrypto();
     });
+
+    it("should migrate from libolm", async () => {
+        fetchMock.get("path:/_matrix/client/v3/room_keys/version", {
+            auth_data: {
+                public_key: "q+HZiJdHl2Yopv9GGvv7EYSzDMrAiRknK4glSdoaomI",
+                signatures: {
+                    "@vdhtest200713:matrix.org": {
+                        "ed25519:gh9fGr39eNZUdWynEMJ/q/WZq/Pk/foFxHXFBFm18ZI":
+                            "reDp6Mu+j+tfUL3/T6f5OBT3N825Lzpc43vvG+RvjX6V+KxXzodBQArgCoeEHLtL9OgSBmNrhTkSOX87MWCKAw",
+                        "ed25519:KMFSTJSMLB":
+                            "F8tyV5W6wNi0GXTdSg+gxSCULQi0EYxdAAqfkyNq58KzssZMw5i+PRA0aI2b+D7NH/aZaJrtiYNHJ0gWLSQvAw",
+                    },
+                },
+            },
+            version: "7",
+            algorithm: "m.megolm_backup.v1.curve25519-aes-sha2",
+            etag: "1",
+            count: 79,
+        });
+
+        const testStoreName = "test-store";
+        await populateStore(testStoreName);
+        const cryptoStore = new IndexedDBCryptoStore(indexedDB, testStoreName);
+
+        const matrixClient = createClient({
+            baseUrl: "http://test.server",
+            userId: "@vdhtest200713:matrix.org",
+            deviceId: "KMFSTJSMLB",
+            cryptoStore,
+            pickleKey: "+1k2Ppd7HIisUY824v7JtV3/oEE4yX0TqtmNPyhaD7o",
+        });
+
+        await matrixClient.initRustCrypto();
+
+        // Do some basic checks on the imported data
+        const deviceKeys = await matrixClient.getCrypto()!.getOwnDeviceKeys();
+        expect(deviceKeys.curve25519).toEqual("LKv0bKbc0EC4h0jknbemv3QalEkeYvuNeUXVRgVVTTU");
+        expect(deviceKeys.ed25519).toEqual("qK70DEqIXq7T+UU3v/al47Ab4JkMEBLpNrTBMbS5rrw");
+
+        expect(await matrixClient.getCrypto()!.getActiveSessionBackupVersion()).toEqual("7");
+    });
 });
 
 describe("MatrixClient.clearStores", () => {

spec/test-utils/test_indexeddb_cryptostore_dump/README.md

@@ -0,0 +1,53 @@
+## Dump of libolm indexeddb cryptostore
+
+This directory contains a dump of a real indexeddb store from a session using
+libolm crypto.
+
+The corresponding pickle key is `+1k2Ppd7HIisUY824v7JtV3/oEE4yX0TqtmNPyhaD7o`.
+
+It was created by pasting the following into the browser console:
+
+```javascript
+async function exportIndexedDb(name) {
+    const db = await new Promise((resolve, reject) => {
+        const dbReq = indexedDB.open(name);
+        dbReq.onerror = reject;
+        dbReq.onsuccess = () => resolve(dbReq.result);
+    });
+
+    const storeNames = db.objectStoreNames;
+    const exports = {};
+    for (const store of storeNames) {
+        exports[store] = [];
+        const txn = db.transaction(store, "readonly");
+        const objectStore = txn.objectStore(store);
+        await new Promise((resolve, reject) => {
+            const cursorReq = objectStore.openCursor();
+            cursorReq.onerror = reject;
+            cursorReq.onsuccess = (event) => {
+                const cursor = event.target.result;
+                if (cursor) {
+                    const entry = { value: cursor.value };
+                    if (!objectStore.keyPath) {
+                        entry.key = cursor.key;
+                    }
+                    exports[store].push(entry);
+                    cursor.continue();
+                } else {
+                    resolve();
+                }
+            };
+        });
+    }
+    return exports;
+}
+
+window.saveAs(
+    new Blob([JSON.stringify(await exportIndexedDb("matrix-js-sdk:crypto"), null, 2)], {
+        type: "application/json;charset=utf-8",
+    }),
+    "dump.json",
+);
+```
+
+The pickle key is extracted via `mxMatrixClientPeg.get().crypto.olmDevice.pickleKey`.