Fix to allow key ring size of 256 and not 255 (#1268)

* Fix to allow key ring size of 256 and not 255

* Changeset

* Add unit test

* Lint

* Fix tests

* Lint

.changeset/breezy-glasses-grow.md

@@ -0,0 +1,5 @@
+---
+'livekit-client': patch
+---
+
+Actually allow E2EE keyring size of 256

src/e2ee/worker/ParticipantKeyHandler.test.ts

@@ -0,0 +1,37 @@
+import { describe, expect, it } from 'vitest';
+import { KEY_PROVIDER_DEFAULTS } from '../constants';
+import { createKeyMaterialFromString } from '../utils';
+import { ParticipantKeyHandler } from './ParticipantKeyHandler';
+
+describe('ParticipantKeyHandler', () => {
+  const participantIdentity = 'testParticipant';
+
+  it('keyringSize must be greater than 0', () => {
+    expect(() => {
+      new ParticipantKeyHandler(participantIdentity, { ...KEY_PROVIDER_DEFAULTS, keyringSize: 0 });
+    }).toThrowError(TypeError);
+  });
+
+  it('keyringSize must be max 256', () => {
+    expect(() => {
+      new ParticipantKeyHandler(participantIdentity, {
+        ...KEY_PROVIDER_DEFAULTS,
+        keyringSize: 257,
+      });
+    }).toThrowError(TypeError);
+  });
+
+  it('get and sets keys at an index', async () => {
+    const keyHandler = new ParticipantKeyHandler(participantIdentity, {
+      ...KEY_PROVIDER_DEFAULTS,
+      keyringSize: 128,
+    });
+    const materialA = await createKeyMaterialFromString('passwordA');
+    const materialB = await createKeyMaterialFromString('passwordB');
+    await keyHandler.setKey(materialA, 0);
+    expect(keyHandler.getKeySet(0)).toBeDefined();
+    expect(keyHandler.getKeySet(0)?.material).toEqual(materialA);
+    await keyHandler.setKey(materialB, 0);
+    expect(keyHandler.getKeySet(0)?.material).toEqual(materialB);
+  });
+});

src/e2ee/worker/ParticipantKeyHandler.ts

@@ -38,7 +38,7 @@ export class ParticipantKeyHandler extends (EventEmitter as new () => TypedEvent
   constructor(participantIdentity: string, keyProviderOptions: KeyProviderOptions) {
     super();
     this.currentKeyIndex = 0;
-    if (keyProviderOptions.keyringSize < 1 || keyProviderOptions.keyringSize > 255) {
+    if (keyProviderOptions.keyringSize < 1 || keyProviderOptions.keyringSize > 256) {
       throw new TypeError('Keyring size needs to be between 1 and 256');
     }
     this.cryptoKeyRing = new Array(keyProviderOptions.keyringSize).fill(undefined);