e2ee: add unit tests

Both for just encode function as well as an end-to-end test.

modules/e2ee/Context.js

@@ -1,4 +1,5 @@
 /* eslint-disable no-bitwise */
+/* global BigInt */
 
 import { deriveKeys, importKey, ratchet } from './crypto-utils';
 import { isArrayEqual } from './utils';
@@ -57,7 +58,7 @@ export class Context {
         // A per-sender counter that is used create the AES CTR.
         // Must be incremented on every frame that is sent, can be reset on
         // key changes.
-        this._sendCount = 0n;
+        this._sendCount = BigInt(0); // eslint-disable-line new-cap
 
         this._id = id;
     }
@@ -90,7 +91,7 @@ export class Context {
      */
     _setKeys(keys) {
         this._cryptoKeyRing[this._currentKeyIndex] = keys;
-        this._sendCount = 0n; // Reset the send count (bigint).
+        this._sendCount = BigInt(0); // eslint-disable-line new-cap
     }
 
     /**

modules/e2ee/Context.spec.js

@@ -0,0 +1,174 @@
+import { Context } from './Context';
+import { ratchet, importKey } from './crypto-utils';
+
+/*
+function hexdump(buffer) {
+    const a = new Uint8Array(buffer);
+    let s = '';
+
+    for (let i = 0; i < a.byteLength; i++) {
+        s += '0x';
+        s += a[i].toString(16);
+        s += ' ';
+    }
+
+    return s.trim();
+}
+*/
+
+/* TODO: more tests
+ * - delta frames
+ * - frame header is not encrypted
+ * - different sendCounts
+ * - different key length
+ * - ratcheting in decodeFunction
+ * etc
+ */
+const audioBytes = [ 0xde, 0xad, 0xbe, 0xef ];
+const videoBytes = [ 0xde, 0xad, 0xbe, 0xef, 0xde, 0xad, 0xbe, 0xef, 0xde, 0xad, 0xbe, 0xef ];
+
+describe('E2EE Context', () => {
+    let sender;
+    let receiver;
+    const key = new Uint8Array([
+        1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+    ]);
+
+    beforeEach(() => {
+        sender = new Context('sender');
+        receiver = new Context('receiver');
+    });
+
+    describe('encode function', () => {
+        it('with an audio frame', async done => {
+            const sendController = {
+                enqueue: encodedFrame => {
+                    const data = new Uint8Array(encodedFrame.data);
+
+                    // An audio frame will have an overhead of 6 bytes with this counter and key size:
+                    //   4 bytes truncated signature, counter (1 byte) and 1 byte trailer.
+                    expect(data.byteLength).toEqual(audioBytes.length + 6);
+
+                    // TODO: provide test vector and matcher.
+                    done();
+                }
+            };
+            const frame = {
+                data: new Uint8Array(audioBytes).buffer,
+                type: undefined // type is undefined for audio frames.
+            };
+
+            await sender.setKey(key, 0);
+            await receiver.setKey(key, 0);
+            await sender.encodeFunction(frame, sendController);
+        });
+
+        it('with a video frame', async done => {
+            const sendController = {
+                enqueue: encodedFrame => {
+                    const data = new Uint8Array(encodedFrame.data);
+
+                    // A video frame will have an overhead of 12 bytes with this counter and key size:
+                    //   10 bytes signature, counter (1 byte) and 1 byte trailer.
+
+                    expect(data.byteLength).toEqual(videoBytes.length + 12);
+
+                    // TODO: provide test vector and matcher.
+                    done();
+                }
+            };
+            const frame = {
+                data: new Uint8Array(videoBytes).buffer,
+                type: 'key'
+            };
+
+            await sender.setKey(key, 0);
+            await receiver.setKey(key, 0);
+            await sender.encodeFunction(frame, sendController);
+        });
+    });
+
+    describe('end-to-end test', () => {
+        it('with an audio frame', async done => {
+            await sender.setKey(key, 0);
+            await receiver.setKey(key, 0);
+            const receiveController = {
+                enqueue: encodedFrame => {
+                    const data = new Uint8Array(encodedFrame.data);
+
+                    expect(data.byteLength).toEqual(audioBytes.length);
+                    expect(Array.from(data)).toEqual(audioBytes);
+                    done();
+                }
+            };
+            const sendController = {
+                enqueue: encodedFrame => {
+                    receiver.decodeFunction(encodedFrame, receiveController);
+                }
+            };
+            const frame = {
+                data: new Uint8Array(audioBytes).buffer,
+                type: undefined // type is undefined for audio frames.
+            };
+
+            await sender.encodeFunction(frame, sendController);
+        });
+
+        it('with a video frame', async done => {
+            await sender.setKey(key, 0);
+            await receiver.setKey(key, 0);
+            const receiveController = {
+                enqueue: encodedFrame => {
+                    const data = new Uint8Array(encodedFrame.data);
+
+                    expect(data.byteLength).toEqual(videoBytes.length);
+                    expect(Array.from(data)).toEqual(videoBytes);
+                    done();
+                }
+            };
+            const sendController = {
+                enqueue: encodedFrame => {
+                    receiver.decodeFunction(encodedFrame, receiveController);
+                }
+            };
+            const frame = {
+                data: new Uint8Array(videoBytes).buffer,
+                type: 'key'
+            };
+
+            await sender.encodeFunction(frame, sendController);
+        });
+
+        it('the receiver ratchets forward', async done => {
+            await sender.setKey(key, 0);
+            await receiver.setKey(key, 0);
+
+            // Ratchet the key. We reimport from the raw bytes.
+            const material = await importKey(key);
+
+            await sender.setKey(await ratchet(material), 0);
+
+            const receiveController = {
+                enqueue: encodedFrame => {
+                    const data = new Uint8Array(encodedFrame.data);
+
+                    expect(data.byteLength).toEqual(audioBytes.length);
+                    expect(Array.from(data)).toEqual(audioBytes);
+                    done();
+                }
+            };
+            const sendController = {
+                enqueue: encodedFrame => {
+                    receiver.decodeFunction(encodedFrame, receiveController);
+                }
+            };
+            const frame = {
+                data: new Uint8Array(audioBytes).buffer,
+                type: undefined
+            };
+
+            await sender.encodeFunction(frame, sendController);
+        });
+    });
+});