feat: add skip muxer negotiation (#3081)

Some transports have their own muxers but use existing encrypers
to do a handshake so skip sending muxer lists as it is not necessary.

Author: achingbrain

packages/connection-encrypter-tls/src/tls.ts

@@ -90,6 +90,12 @@ export class TLS implements ConnectionEncrypter {
   async _encrypt <Stream extends Duplex<AsyncGenerator<Uint8Array | Uint8ArrayList>> = MultiaddrConnection> (conn: Stream, isServer: boolean, options?: SecureConnectionOptions): Promise<SecuredConnection<Stream>> {
     let streamMuxer: StreamMuxerFactory | undefined
 
+    let streamMuxers: string[] = []
+
+    if (options?.skipStreamMuxerNegotiation !== true) {
+      streamMuxers = [...this.components.upgrader.getStreamMuxers().keys()]
+    }
+
     const opts: TLSSocketOptions = {
       ...await generateCertificate(this.components.privateKey),
       isServer,
@@ -101,7 +107,7 @@ export class TLS implements ConnectionEncrypter {
 
       // early negotiation of muxer via ALPN protocols
       ALPNProtocols: [
-        ...this.components.upgrader.getStreamMuxers().keys(),
+        ...streamMuxers,
         'libp2p'
       ],
       ALPNCallback: ({ protocols }) => {
@@ -158,17 +164,9 @@ export class TLS implements ConnectionEncrypter {
           .then(remotePeer => {
             this.log('remote certificate ok, remote peer %p', remotePeer)
 
-            if (!isServer && typeof socket.alpnProtocol === 'string') {
-              streamMuxer = this.components.upgrader.getStreamMuxers().get(socket.alpnProtocol)
-
-              if (streamMuxer == null) {
-                this.log.error('selected muxer that did not exist')
-              }
-            }
-
             // 'libp2p' is a special protocol - if it's sent the remote does not
             // support early muxer negotiation
-            if (!isServer && typeof socket.alpnProtocol === 'string' && socket.alpnProtocol !== 'libp2p') {
+            if (!isServer && typeof socket.alpnProtocol === 'string' && socket.alpnProtocol !== 'libp2p' && options?.skipStreamMuxerNegotiation !== true) {
               this.log.trace('got early muxer', socket.alpnProtocol)
               streamMuxer = this.components.upgrader.getStreamMuxers().get(socket.alpnProtocol)
 

packages/connection-encrypter-tls/test/index.spec.ts

@@ -113,4 +113,26 @@ describe('tls', () => {
     expect(result).to.have.nested.property('[0].streamMuxer.protocol', '/test/muxer')
     expect(result).to.have.nested.property('[1].streamMuxer.protocol', '/test/muxer')
   })
+
+  it('should not select an early muxer when it is skipped', async () => {
+    const [inbound, outbound] = duplexPair<any>()
+
+    const result = await Promise.all([
+      encrypter.secureInbound(stubInterface<MultiaddrConnection>({
+        ...inbound
+      }), {
+        remotePeer: localPeer,
+        skipStreamMuxerNegotiation: true
+      }),
+      encrypter.secureOutbound(stubInterface<MultiaddrConnection>({
+        ...outbound
+      }), {
+        remotePeer: localPeer,
+        skipStreamMuxerNegotiation: true
+      })
+    ])
+
+    expect(result).to.have.nested.property('[0].streamMuxer', undefined)
+    expect(result).to.have.nested.property('[1].streamMuxer', undefined)
+  })
 })

packages/interface/src/connection-encrypter.ts

@@ -11,6 +11,14 @@ import type { Uint8ArrayList } from 'uint8arraylist'
  */
 export interface SecureConnectionOptions extends AbortOptions {
   remotePeer?: PeerId
+
+  /**
+   * Some encryption protocols allow negotiating application protocols as part
+   * of the initial handshake. The negotiated stream muxer protocol will be
+   * included as part of the from the `secureOutbound`/`secureInbound` methods
+   * unless `false` is passed here.
+   */
+  skipStreamMuxerNegotiation?: boolean
 }
 
 /**