Create handshake interface to support performing different handshakes

src/@types/handshake-interface.ts

@@ -0,0 +1,8 @@
+import {bytes} from "./basic";
+import {NoiseSession} from "./handshake";
+
+export interface HandshakeInterface {
+  session: NoiseSession;
+  encrypt(plaintext: bytes, session: NoiseSession): bytes;
+  decrypt(ciphertext: bytes, session: NoiseSession): bytes;
+}

src/crypto.ts

@@ -1,5 +1,5 @@
 import { Buffer } from "buffer";
-import { Handshake } from "./handshake-xx";
+import {HandshakeInterface} from "./@types/handshake-interface";
 
 interface ReturnEncryptionWrapper {
   (source: Iterable<Uint8Array>): AsyncIterableIterator<Uint8Array>;
@@ -8,7 +8,7 @@ interface ReturnEncryptionWrapper {
 const maxPlaintextLength = 65519;
 
 // Returns generator that encrypts payload from the user
-export function encryptStream(handshake: Handshake): ReturnEncryptionWrapper {
+export function encryptStream(handshake: HandshakeInterface): ReturnEncryptionWrapper {
   return async function * (source) {
     for await (const chunk of source) {
       const chunkBuffer = Buffer.from(chunk.buffer, chunk.byteOffset, chunk.length);
@@ -28,7 +28,7 @@ export function encryptStream(handshake: Handshake): ReturnEncryptionWrapper {
 
 
 // Decrypt received payload to the user
-export function decryptStream(handshake: Handshake): ReturnEncryptionWrapper {
+export function decryptStream(handshake: HandshakeInterface): ReturnEncryptionWrapper {
   return async function * (source) {
     for await (const chunk of source) {
       const chunkBuffer = Buffer.from(chunk.buffer, chunk.byteOffset, chunk.length);

src/handshake-ik.ts

@@ -4,7 +4,7 @@ import {KeyPair, PeerId} from "./@types/libp2p";
 import {WrappedConnection} from "./noise";
 import {IKHandshake} from "./handshakes/ik";
 
-export class Handshake {
+export class Handshake { // implements HandshakeHandler
   public isInitiator: boolean;
   public session: NoiseSession;
 

src/handshake-xx.ts

@@ -4,6 +4,7 @@ import { XXHandshake } from "./handshakes/xx";
 import { KeyPair, PeerId } from "./@types/libp2p";
 import { bytes, bytes32 } from "./@types/basic";
 import { NoiseSession } from "./@types/handshake";
+import {HandshakeInterface} from "./@types/handshake-interface";
 import {
   createHandshakePayload,
   getHandshakePayload,
@@ -15,7 +16,7 @@ import { logger } from "./logger";
 import { decodeMessageBuffer, encodeMessageBuffer } from "./encoder";
 import { WrappedConnection } from "./noise";
 
-export class Handshake {
+export class Handshake implements HandshakeInterface {
   public isInitiator: boolean;
   public session: NoiseSession;
 
@@ -50,7 +51,7 @@ export class Handshake {
   }
 
   // stage 0
-  async propose(): Promise<void> {
+  public async propose(): Promise<void> {
     if (this.isInitiator) {
       logger("Stage 0 - Initiator starting to send first message.");
       const messageBuffer = this.xx.sendMessage(this.session, Buffer.alloc(0));
@@ -65,7 +66,7 @@ export class Handshake {
   }
 
   // stage 1
-  async exchange(): Promise<void> {
+  public async exchange(): Promise<void> {
     if (this.isInitiator) {
       logger('Stage 1 - Initiator waiting to receive first message from responder...');
       const receivedMessageBuffer = decodeMessageBuffer((await this.connection.readLP()).slice());
@@ -97,7 +98,7 @@ export class Handshake {
   }
 
   // stage 2
-  async finish(earlyData?: bytes): Promise<void> {
+  public async finish(earlyData?: bytes): Promise<void> {
     if (this.isInitiator) {
       logger('Stage 2 - Initiator sending third handshake message.');
       const signedPayload = signPayload(this.libp2pPrivateKey, getHandshakePayload(this.staticKeys.publicKey));

src/noise.ts

@@ -6,13 +6,15 @@ import ensureBuffer from 'it-buffer';
 import pipe from 'it-pipe';
 import lp from 'it-length-prefixed';
 
-import { Handshake } from "./handshake-xx";
+import { Handshake as XX } from "./handshake-xx";
 import { generateKeypair } from "./utils";
 import { uint16BEDecode, uint16BEEncode } from "./encoder";
 import { decryptStream, encryptStream } from "./crypto";
 import { bytes } from "./@types/basic";
 import { NoiseConnection, PeerId, KeyPair, SecureOutbound } from "./@types/libp2p";
 import { Duplex } from "./@types/it-pair";
+import {XXHandshake} from "./handshakes/xx";
+import {HandshakeInterface} from "./@types/handshake-interface";
 
 export type WrappedConnection = ReturnType<typeof Wrap>;
 
@@ -89,24 +91,22 @@ export class Noise implements NoiseConnection {
     isInitiator: boolean,
     libp2pPublicKey: bytes,
     remotePeer: PeerId,
-  ): Promise<Handshake> {
+  ): Promise<HandshakeInterface> {
+    // TODO: Implement noise pipes
+
     if (false) {
-      // TODO: Implement noise pipes
 
     } else {
-      return await this.performXXHandshake(connection, isInitiator, libp2pPublicKey, remotePeer)
+      const prologue = Buffer.from(this.protocol);
+      const handshake = new XX(isInitiator, this.privateKey, libp2pPublicKey, prologue, this.staticKeys, connection, remotePeer);
+
+      return await this.performXXHandshake(handshake);
     }
   }
 
   private async performXXHandshake(
-    connection: WrappedConnection,
-    isInitiator: boolean,
-    libp2pPublicKey: bytes,
-    remotePeer: PeerId,
-  ): Promise<Handshake> {
-    const prologue = Buffer.from(this.protocol);
-    const handshake = new Handshake(isInitiator, this.privateKey, libp2pPublicKey, prologue, this.staticKeys, connection, remotePeer);
-
+    handshake: XX
+  ): Promise<HandshakeInterface> {
     try {
       await handshake.propose();
       await handshake.exchange();
@@ -120,7 +120,7 @@ export class Noise implements NoiseConnection {
 
   private async createSecureConnection(
     connection: WrappedConnection,
-    handshake: Handshake,
+    handshake: HandshakeInterface,
   ): Promise<Duplex> {
     // Create encryption box/unbox wrapper
     const [secure, user] = DuplexPair();