Merge pull request #14 from maelvls/readonly-for-guestbook

Readonly access for the guestbook

guestbook/go.mod

@@ -2,16 +2,22 @@ module github.com/cert-manager/print-your-cert/guestbook
 
 go 1.22
 
-require modernc.org/sqlite v1.29.1
+require (
+	golang.org/x/crypto v0.21.0
+	modernc.org/sqlite v1.29.1
+)
 
 require (
 	github.com/dustin/go-humanize v1.0.1 // indirect
 	github.com/google/uuid v1.3.0 // indirect
 	github.com/hashicorp/golang-lru/v2 v2.0.7 // indirect
+	github.com/inconshreveable/go-vhost v1.0.0
 	github.com/mattn/go-isatty v0.0.16 // indirect
 	github.com/ncruces/go-strftime v0.1.9 // indirect
 	github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec // indirect
-	golang.org/x/sys v0.16.0 // indirect
+	golang.org/x/net v0.21.0 // indirect
+	golang.org/x/sys v0.18.0 // indirect
+	golang.org/x/text v0.14.0 // indirect
 	modernc.org/gc/v3 v3.0.0-20240107210532-573471604cb6 // indirect
 	modernc.org/libc v1.41.0 // indirect
 	modernc.org/mathutil v1.6.0 // indirect

guestbook/go.sum

@@ -6,6 +6,8 @@ github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
 github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/hashicorp/golang-lru/v2 v2.0.7 h1:a+bsQ5rvGLjzHuww6tVxozPZFVghXaHOwFs4luLUK2k=
 github.com/hashicorp/golang-lru/v2 v2.0.7/go.mod h1:QeFd9opnmA6QUJc5vARoKUSoFhyfM2/ZepoAG6RGpeM=
+github.com/inconshreveable/go-vhost v1.0.0 h1:IK4VZTlXL4l9vz2IZoiSFbYaaqUW7dXJAiPriUN5Ur8=
+github.com/inconshreveable/go-vhost v1.0.0/go.mod h1:aA6DnFhALT3zH0y+A39we+zbrdMC2N0X/q21e6FI0LU=
 github.com/mattn/go-isatty v0.0.16 h1:bq3VjFmv/sOjHtdEhmkEV4x1AJtvUvOJ2PFAZ5+peKQ=
 github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
 github.com/mattn/go-sqlite3 v1.14.16 h1:yOQRA0RpS5PFz/oikGwBEqvAWhWg5ufRz4ETLjwpU1Y=
@@ -16,11 +18,17 @@ github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZb
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec h1:W09IVJc94icq4NjY3clb7Lk8O1qJ8BdBEF8z0ibU0rE=
 github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec/go.mod h1:qqbHyh8v60DhA7CoWK5oRCqLrMHRGoxYCSS9EjAz6Eo=
+golang.org/x/crypto v0.21.0 h1:X31++rzVUdKhX5sWmSOFZxx8UW/ldWx55cbf08iNAMA=
+golang.org/x/crypto v0.21.0/go.mod h1:0BP7YvVV9gBbVKyeTG0Gyn+gZm94bibOW5BjDEYAOMs=
 golang.org/x/mod v0.14.0 h1:dGoOF9QVLYng8IHTm7BAyWqCqSheQ5pYWGhzW00YJr0=
 golang.org/x/mod v0.14.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
+golang.org/x/net v0.21.0 h1:AQyQV4dYCvJ7vGmJyKki9+PBdyvhkSd8EIx/qb0AYv4=
+golang.org/x/net v0.21.0/go.mod h1:bIjVDfnllIU7BJ2DNgfnXvpSvtn8VRwhlsaeUTyUS44=
 golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.16.0 h1:xWw16ngr6ZMtmxDyKyIgsE93KNKz5HKmMa3b8ALHidU=
-golang.org/x/sys v0.16.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/sys v0.18.0 h1:DBdB3niSjOA/O0blCZBqDefyWNYveAYMNF1Wum0DYQ4=
+golang.org/x/sys v0.18.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/text v0.14.0 h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ=
+golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
 golang.org/x/tools v0.17.0 h1:FvmRgNOcs3kOa+T20R1uhfP9F6HgG2mfxDv1vrx1Htc=
 golang.org/x/tools v0.17.0/go.mod h1:xsh6VxdV005rRVaS6SSAf9oiAqljS7UZUacMZ8Bnsps=
 modernc.org/gc/v3 v3.0.0-20240107210532-573471604cb6 h1:5D53IMaUuA5InSeMu9eJtlQXS2NxAhyWQvkKEgXZhHI=

guestbook/main.go

@@ -19,6 +19,8 @@ import (
 	"text/tabwriter"
 	"time"
 
+	"github.com/inconshreveable/go-vhost"
+	"golang.org/x/crypto/acme/autocert"
 	_ "modernc.org/sqlite"
 )
 
@@ -27,6 +29,12 @@ var (
 	caCertPath     = flag.String("ca-cert", "", "Path to CA certs to trust for client certs")
 	chainPath      = flag.String("tls-chain", "", "Path to TLS cert chain")
 	privateKeyPath = flag.String("tls-key", "", "Path to TLS private key")
+	mainDomain     = flag.String("domain", "guestbook.print-your-cert.cert-manager.io", "Domain used to access the guestbook. Used for SNI routing.")
+
+	readOnlyDomain         = flag.String("readonly-domain", "readonly-guestbook.print-your-cert.cert-manager.io", "Domain used to access the guestbook in read-only mode")
+	readOnlyListenInsecure = flag.String("readonly-listen-insecure", "0.0.0.0:8080", "Address and port to listen on. Must be 80 if -prod is set.")
+	readOnlyProd           = flag.Bool("prod", false, "If true, enables HTTPS for the readonly domain using Let's Encrypt.")
+	readOnlyAutocertDir    = flag.String("autocert-dir", ".", "The directory used to cache the certificate and temporary files to work with Let's Encrypt.")
 
 	dbPath = flag.String("db-path", "guestbook.sqlite", "Path to sqlite database")
 	initDB = flag.Bool("init-db", false, "If set, initialise a fresh database at db-path")
@@ -224,8 +232,15 @@ func run(ctx context.Context) error {
 		return fmt.Errorf("missing required path to CA cert")
 	}
 
+	if *readOnlyProd && !strings.HasSuffix(*readOnlyListenInsecure, ":80") {
+		return fmt.Errorf("with -prod, use -readonly-listen-insecure=:80 so that Let's Encrypt can verify the domain")
+	}
+
 	logger := LoggerFromContext(ctx)
 
+	sigs := make(chan os.Signal, 1)
+	signal.Notify(sigs, syscall.SIGINT)
+
 	db, err := sql.Open("sqlite", *dbPath)
 	if err != nil {
 		return err
@@ -241,50 +256,113 @@ func run(ctx context.Context) error {
 		return err
 	}
 
-	serveMux := http.NewServeMux()
+	listener, err := net.Listen("tcp", *listen)
+	if err != nil {
+		return fmt.Errorf("failed to create TCP listener: %s", err)
+	}
+	tlsMux, err := vhost.NewTLSMuxer(listener, time.Second*5)
+	if err != nil {
+		return fmt.Errorf("failed to create vhost muxer: %s", err)
+	}
 
+	serveMux := http.NewServeMux()
 	serveMux.Handle("GET /", certExtractMiddleware(indexPage(db)))
 	serveMux.Handle("POST /write", certExtractMiddleware(writePage(db)))
-
 	server := &http.Server{
 		Handler:     serveMux,
-		BaseContext: func(_ net.Listener) context.Context { return ctx },
-		ErrorLog:    slog.NewLogLogger(logger.With("handler", "http.Server").Handler(), slog.LevelError),
+		BaseContext: func(l net.Listener) context.Context { return ctx },
+		ErrorLog:    slog.NewLogLogger(logger.With("handler", "http.Server", "server", "main-server").Handler(), slog.LevelError),
 	}
-
-	listener, err := net.Listen("tcp", *listen)
+	serverListener, err := tlsMux.Listen(*mainDomain)
 	if err != nil {
-		return fmt.Errorf("failed to create TCP listener: %s", err)
+		return fmt.Errorf("failed to create vhost listener: %s", err)
 	}
+	go func() {
+		logger.Info("main-server listening", "address", *listen, "sni", *mainDomain)
+		err := server.Serve(tls.NewListener(serverListener, &tls.Config{
+			Certificates: []tls.Certificate{cert},
+			ClientCAs:    certPool,
+			ClientAuth:   tls.RequireAndVerifyClientCert,
+		}))
+		if err != nil && err != http.ErrServerClosed {
+			logger.Info("failed to listen", "error", err)
+		}
+	}()
 
-	tlsConfig := &tls.Config{
-		Certificates: []tls.Certificate{cert},
-		ClientCAs:    certPool,
-		ClientAuth:   tls.RequireAndVerifyClientCert,
+	readOnlyMux := http.NewServeMux()
+	readOnlyMux.Handle("GET /", indexPage(db))
+	readOnlySrv := &http.Server{
+		Handler:     readOnlyMux,
+		BaseContext: func(_ net.Listener) context.Context { return ctx },
+		ErrorLog:    slog.NewLogLogger(logger.With("handler", "http.Server", "server", "readonly-server-https").Handler(), slog.LevelError),
+	}
+	mgr := &autocert.Manager{
+		Prompt: autocert.AcceptTOS,
+		HostPolicy: func(ctx context.Context, host string) error {
+			allowedHost := *readOnlyDomain
+			if host == allowedHost {
+				return nil
+			}
+			return fmt.Errorf("acme/autocert: only %s host is allowed", allowedHost)
+		},
+		Cache: autocert.DirCache(*readOnlyAutocertDir),
+	}
+	readOnlyListener, err := tlsMux.Listen(*readOnlyDomain)
+	if err != nil {
+		return fmt.Errorf("failed to create vhost listener: %s", err)
 	}
 
-	listener = tls.NewListener(listener, tlsConfig)
-
-	logger.Info("listening", "address", *listen)
-
-	sigs := make(chan os.Signal, 1)
-
-	signal.Notify(sigs, syscall.SIGINT)
+	go func() {
+		if !*readOnlyProd {
+			logger.Info("readonly-server not enabled, use -prod to turn it on")
+			return
+		}
+		logger.Info("readonly-server-https listening", "address", *listen, "sni", *readOnlyDomain)
+		err := readOnlySrv.Serve(tls.NewListener(readOnlyListener, &tls.Config{
+			GetCertificate: mgr.GetCertificate,
+		}))
+		if err != nil && err != http.ErrServerClosed {
+			logger.Info("failed to listen", "error", err)
+		}
+	}()
 
+	readOnlySrvHTTP := &http.Server{
+		Handler:     readOnlyMux,
+		BaseContext: func(_ net.Listener) context.Context { return ctx },
+		ErrorLog:    slog.NewLogLogger(logger.With("handler", "http.Server", "server", "readonly-server-http").Handler(), slog.LevelError),
+		Addr:        *readOnlyListenInsecure,
+	}
+	if mgr != nil {
+		// Allows autocert handle Let's Encrypt HTTP-01 callbacks.
+		readOnlySrv.Handler = mgr.HTTPHandler(readOnlySrvHTTP.Handler)
+	}
 	go func() {
-		err := server.Serve(listener)
+		logger.Info("readonly-server-http listening", "address", *readOnlyListenInsecure)
+		err := readOnlySrv.ListenAndServe()
 		if err != nil && err != http.ErrServerClosed {
 			logger.Info("failed to listen", "error", err)
 		}
 	}()
 
+	go tlsMux.HandleErrors()
+
 	<-sigs
 	logger.Info("shutting down")
 
 	err = server.Shutdown(context.Background())
 	if err != nil {
 		return err
 	}
+	err = readOnlySrv.Shutdown(context.Background())
+	if err != nil {
+		return err
+	}
+	if readOnlySrvHTTP != nil {
+		err = readOnlySrvHTTP.Shutdown(context.Background())
+		if err != nil {
+			return err
+		}
+	}
 
 	return nil
 }