Simplify the fingerprint code.

There was a lot of stuff left over from experimentation.

cert/generate

@@ -17,4 +17,4 @@ go run filippo.io/mkcert -ecdsa -install
 go run filippo.io/mkcert -ecdsa -days 10 -cert-file "$CRT" -key-file "$KEY" localhost 127.0.0.1 ::1
 
 # Compute the sha256 fingerprint of the certificate for WebTransport
-openssl x509 -in "$CRT" -outform der | openssl dgst -sha256 > ../player/src/transport/fingerprint.hex
+openssl x509 -in "$CRT" -outform der | openssl dgst -sha256 > ../player/fingerprint.hex

player/.gitignore

@@ -1,3 +1,4 @@
 node_modules
 .parcel-cache
 dist
+fingerprint.hex

player/src/index.ts

@@ -1,5 +1,14 @@
 import Player from "./player"
 
+// @ts-ignore embed the certificate fingerprint using bundler
+import fingerprintHex from 'bundle-text:../fingerprint.hex';
+
+// Convert the hex to binary.
+let fingerprint = [];
+for (let c = 0; c < fingerprintHex.length-1; c += 2) {
+    fingerprint.push(parseInt(fingerprintHex.substring(c, c+2), 16));
+}
+
 const params = new URLSearchParams(window.location.search)
 
 const url = params.get("url") || "https://localhost:4443/watch"
@@ -7,6 +16,10 @@ const canvas = document.querySelector<HTMLCanvasElement>("canvas#video")!
 
 const player = new Player({
     url: url,
+    fingerprint: { // TODO remove when Chrome accepts the system CA
+        "algorithm": "sha-256",
+        "value": new Uint8Array(fingerprint),
+    },
     canvas: canvas,
 })
 

player/src/player/index.ts

@@ -4,6 +4,7 @@ import Video from "../video"
 
 export interface PlayerInit {
 	url: string;
+	fingerprint?: WebTransportHash; // the certificate fingerprint, temporarily needed for local development
 	canvas: HTMLCanvasElement;
 }
 
@@ -20,6 +21,8 @@ export default class Player {
 
         this.transport = new Transport({
             url: props.url,
+			fingerprint: props.fingerprint,
+
             audio: this.audio,
             video: this.video,
         })
@@ -29,10 +32,6 @@ export default class Player {
         this.transport.close()
 	}
 
-	async connect(url: string) {
-        await this.transport.connect(url)
-	}
-
 	play() {
 		this.audio.play({})
 		//this.video.play()

player/src/transport/.gitignore

@@ -1 +0,0 @@
-fingerprint.hex

player/src/transport/index.ts

@@ -5,11 +5,10 @@ import * as MP4 from "../mp4"
 import Audio from "../audio"
 import Video from "../video"
 
-// @ts-ignore bundler embeds data
-import fingerprint from 'bundle-text:./fingerprint.hex';
-
 export interface TransportInit {
 	url: string;
+	fingerprint?: WebTransportHash; // the certificate fingerprint, temporarily needed for local development
+
 	audio: Audio;
 	video: Video;
 }
@@ -28,7 +27,7 @@ export default class Transport {
 		this.audio = props.audio;
 		this.video = props.video;
 
-		this.quic = this.connect(props.url)
+		this.quic = this.connect(props)
 
 		// Create a unidirectional stream for all of our messages
 		this.api = this.quic.then((q) => {
@@ -43,22 +42,16 @@ export default class Transport {
 		(await this.quic).close()
 	}
 
-	async connect(url: string): Promise<WebTransport> {
+	// Helper function to make creating a promise easier
-		// Convert the hex to binary.
+	private async connect(props: TransportInit): Promise<WebTransport> {
-		let hash = [];
+
-		for (let c = 0; c < fingerprint.length-1; c += 2) {
+		let options: WebTransportOptions = {};
-			hash.push(parseInt(fingerprint.substring(c, c+2), 16));
+		if (props.fingerprint) {
+			options.serverCertificateHashes = [ props.fingerprint ]
 		}
 
-		const quic = new WebTransport(url, {
+		const quic = new WebTransport(props.url, options)
-			"serverCertificateHashes": [{
-				"algorithm": "sha-256",
-				"value": new Uint8Array(hash),
-			}]
-		})
-
 		await quic.ready
-
 		return quic
 	}
 

server/internal/web/web.go

@@ -1,64 +0,0 @@
-package web
-
-import (
-	"context"
-	"log"
-	"net/http"
-	"time"
-
-	"github.com/kixelated/invoker"
-)
-
-type Server struct {
-	inner  http.Server
-	config Config
-}
-
-type Config struct {
-	Addr        string
-	CertFile    string
-	KeyFile     string
-	Fingerprint string // the TLS certificate fingerprint
-}
-
-func New(config Config) (s *Server) {
-	s = new(Server)
-	s.config = config
-
-	s.inner = http.Server{
-		Addr: config.Addr,
-	}
-
-	http.HandleFunc("/fingerprint", s.handleFingerprint)
-
-	return s
-}
-
-func (s *Server) Run(ctx context.Context) (err error) {
-	return invoker.Run(ctx, s.runServe, s.runShutdown)
-}
-
-func (s *Server) runServe(context.Context) (err error) {
-	// NOTE: Doesn't support context, which is why we need runShutdown
-	err = s.inner.ListenAndServeTLS(s.config.CertFile, s.config.KeyFile)
-	log.Println(err)
-	return err
-}
-
-// Gracefully shut down the server when the context is cancelled
-func (s *Server) runShutdown(ctx context.Context) (err error) {
-	<-ctx.Done()
-
-	timeout, cancel := context.WithTimeout(context.Background(), 5*time.Second)
-	defer cancel()
-	_ = s.inner.Shutdown(timeout)
-
-	return ctx.Err()
-}
-
-// Return the sha256 of the certificate as a temporary work-around for local development.
-// TODO remove this when WebTransport uses the system CA
-func (s *Server) handleFingerprint(w http.ResponseWriter, r *http.Request) {
-	w.Header().Set("Access-Control-Allow-Origin", "*")
-	_, _ = w.Write([]byte(s.config.Fingerprint))
-}

server/main.go

@@ -2,16 +2,13 @@ package main
 
 import (
 	"context"
-	"crypto/sha256"
 	"crypto/tls"
-	"encoding/hex"
 	"flag"
 	"fmt"
 	"log"
 
 	"github.com/kixelated/invoker"
 	"github.com/kixelated/warp/server/internal/warp"
-	"github.com/kixelated/warp/server/internal/web"
 )
 
 func main() {
@@ -53,19 +50,7 @@ func run(ctx context.Context) (err error) {
 		return fmt.Errorf("failed to create warp server: %w", err)
 	}
 
-	hash := sha256.Sum256(tlsCert.Certificate[0])
-	fingerprint := hex.EncodeToString(hash[:])
-
-	webConfig := web.Config{
-		Addr:        *addr,
-		CertFile:    *cert,
-		KeyFile:     *key,
-		Fingerprint: fingerprint,
-	}
-
-	webServer := web.New(webConfig)
-
 	log.Printf("listening on %s", *addr)
 
-	return invoker.Run(ctx, invoker.Interrupt, warpServer.Run, webServer.Run)
+	return invoker.Run(ctx, invoker.Interrupt, warpServer.Run)
 }