Allow REST endpoints to hijack readers to allow file upload and download

cmd/guac/guac.go

@@ -9,46 +9,98 @@ import (
 	"net/url"
 	"strconv"
 
+	"github.com/gorilla/mux"
+	"github.com/gorilla/websocket"
 	"github.com/sirupsen/logrus"
 	"github.com/wwt/guac"
 )
 
+var tunnels map[string]guac.Tunnel
+
 func main() {
 	logrus.SetLevel(logrus.DebugLevel)
 
-	servlet := guac.NewServer(DemoDoConnect)
+	// servlet := guac.NewServer(DemoDoConnect)
 	wsServer := guac.NewWebsocketServer(DemoDoConnect)
+	wsServerIntercept := guac.NewWebsocketServer(DemoDoConnectWithIntercept)
 
 	sessions := guac.NewMemorySessionStore()
-	wsServer.OnConnect = sessions.Add
-	wsServer.OnDisconnect = sessions.Delete
-
-	mux := http.NewServeMux()
-	mux.Handle("/tunnel", servlet)
-	mux.Handle("/tunnel/", servlet)
-	mux.Handle("/websocket-tunnel", wsServer)
-	mux.HandleFunc("/sessions/", func(w http.ResponseWriter, r *http.Request) {
-		w.Header().Set("Content-Type", "application/json")
+	wsServerIntercept.OnConnect = sessions.Add
+	wsServerIntercept.OnDisconnect = sessions.Delete
+
+	tunnels = make(map[string]guac.Tunnel)
+
+	wsServerIntercept.OnConnectWs = func(s string, _ *websocket.Conn, _ *http.Request, t guac.Tunnel) {
+		tunnels[s] = t
+	}
+
+	wsServerIntercept.OnDisconnectWs = func(s string, _ *websocket.Conn, _ *http.Request, _ guac.Tunnel) {
+		delete(tunnels, s)
+	}
+
+	m := mux.NewRouter()
+
+	// m.Handle("/", servlet)
+	m.Handle("/websocket-tunnel", wsServer)
+	m.Handle("/websocket-tunnel-intercept", wsServerIntercept)
+
+	m.HandleFunc("/api/session/tunnels/{tunnel}/streams/{stream}/{file}", func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Disposition", "attachment")
+		t := mux.Vars(r)["tunnel"]
+
+		tunnel, ok := tunnels[t]
+		if !ok {
+			w.Write([]byte("KO"))
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		}
+
+		sit, ok := tunnel.(*guac.UserTunnel)
+		if !ok {
+			w.Write([]byte("Not supported"))
+			w.WriteHeader(http.StatusBadRequest)
+			return
+		}
+
+		stream := mux.Vars(r)["stream"]
+
+		if err := sit.InterceptOutputStream(stream, w); err != nil {
+			w.Write([]byte("KO Intercepting output stream"))
+		}
+	}).Methods("GET")
+
+	m.HandleFunc("/api/session/tunnels/{tunnel}/streams/{stream}/{file}", func(w http.ResponseWriter, r *http.Request) {
+		t := mux.Vars(r)["tunnel"]
+		tunnel, ok := tunnels[t]
+		if !ok {
+			w.WriteHeader(http.StatusInternalServerError)
+			w.Write([]byte("KO"))
+			return
+		}
+
+		sit, ok := tunnel.(*guac.UserTunnel)
+		if !ok {
+			w.Write([]byte("Not supported"))
+			w.WriteHeader(http.StatusBadRequest)
+			return
+		}
 
-		sessions.RLock()
-		defer sessions.RUnlock()
+		stream := mux.Vars(r)["stream"]
 
-		type ConnIds struct {
-			Uuid string `json:"uuid"`
-			Num  int    `json:"num"`
+		if err := sit.InterceptInputStream(stream, r.Body); err != nil {
+			w.Write([]byte("KO intercepting input stream"))
 		}
+	}).Methods("POST")
 
-		connIds := make([]*ConnIds, len(sessions.ConnIds))
+	m.HandleFunc("/api/session/tunnels", func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
 
-		i := 0
-		for id, num := range sessions.ConnIds {
-			connIds[i] = &ConnIds{
-				Uuid: id,
-				Num:  num,
-			}
+		t := []string{}
+		for tun := range tunnels {
+			t = append(t, tun)
 		}
 
-		if err := json.NewEncoder(w).Encode(connIds); err != nil {
+		if err := json.NewEncoder(w).Encode(t); err != nil {
 			logrus.Error(err)
 		}
 	})
@@ -57,7 +109,7 @@ func main() {
 
 	s := &http.Server{
 		Addr:           "0.0.0.0:4567",
-		Handler:        mux,
+		Handler:        m,
 		ReadTimeout:    guac.SocketTimeout,
 		WriteTimeout:   guac.SocketTimeout,
 		MaxHeaderBytes: 1 << 20,
@@ -69,7 +121,7 @@ func main() {
 }
 
 // DemoDoConnect creates the tunnel to the remote machine (via guacd)
-func DemoDoConnect(request *http.Request) (guac.Tunnel, error) {
+func DemoDoConnect(request *http.Request) (_ guac.Tunnel, err error) {
 	config := guac.NewGuacamoleConfiguration()
 
 	var query url.Values
@@ -93,12 +145,10 @@ func DemoDoConnect(request *http.Request) (guac.Tunnel, error) {
 	}
 
 	config.Protocol = query.Get("scheme")
-	config.Parameters = map[string]string{}
 	for k, v := range query {
 		config.Parameters[k] = v[0]
 	}
 
-	var err error
 	if query.Get("width") != "" {
 		config.OptimalScreenHeight, err = strconv.Atoi(query.Get("width"))
 		if err != nil || config.OptimalScreenHeight == 0 {
@@ -117,6 +167,10 @@ func DemoDoConnect(request *http.Request) (guac.Tunnel, error) {
 
 	logrus.Debug("Connecting to guacd")
 	addr, err := net.ResolveTCPAddr("tcp", "127.0.0.1:4822")
+	if err != nil {
+		logrus.Errorln("error while resolving 127.0.0.1")
+		return nil, err
+	}
 
 	conn, err := net.DialTCP("tcp", nil, addr)
 	if err != nil {
@@ -130,11 +184,23 @@ func DemoDoConnect(request *http.Request) (guac.Tunnel, error) {
 	if request.URL.Query().Get("uuid") != "" {
 		config.ConnectionID = request.URL.Query().Get("uuid")
 	}
+
 	logrus.Debugf("Starting handshake with %#v", config)
 	err = stream.Handshake(config)
 	if err != nil {
 		return nil, err
 	}
 	logrus.Debug("Socket configured")
+
 	return guac.NewSimpleTunnel(stream), nil
 }
+
+// DemoDoConnectWithIntercept showcases a use for intercepting streams
+func DemoDoConnectWithIntercept(r *http.Request) (guac.Tunnel, error) {
+	t, err := DemoDoConnect(r)
+	if err != nil {
+		return nil, err
+	}
+
+	return guac.NewUserTunnel(t), nil
+}

config.go

@@ -5,22 +5,22 @@ type Config struct {
 	// ConnectionID is used to reconnect to an existing session, otherwise leave blank for a new session.
 	ConnectionID string
 	// Protocol is the protocol of the connection from guacd to the remote (rdp, ssh, etc).
-	Protocol     string
+	Protocol string
 	// Parameters are used to configure protocol specific options like sla for rdp or terminal color schemes.
-	Parameters   map[string]string
+	Parameters map[string]string
 
 	// OptimalScreenWidth is the desired width of the screen
-	OptimalScreenWidth  int
+	OptimalScreenWidth int
 	// OptimalScreenHeight is the desired height of the screen
 	OptimalScreenHeight int
 	// OptimalResolution is the desired resolution of the screen
-	OptimalResolution   int
+	OptimalResolution int
 	// AudioMimetypes is an array of the supported audio types
-	AudioMimetypes      []string
+	AudioMimetypes []string
 	// VideoMimetypes is an array of the supported video types
-	VideoMimetypes      []string
+	VideoMimetypes []string
 	// ImageMimetypes is an array of the supported image types
-	ImageMimetypes      []string
+	ImageMimetypes []string
 }
 
 // NewGuacamoleConfiguration returns a Config with sane defaults

doc.go

@@ -1,4 +1,4 @@
 /*
 Package guac implements a HTTP client and a WebSocket client that connects to an Apache Guacamole server.
- */
+*/
 package guac

filter.go

@@ -0,0 +1,5 @@
+package guac
+
+type Filter interface {
+	Filter(*Instruction) (*Instruction, error)
+}

go.mod

@@ -6,6 +6,7 @@ replace github.com/Sirupsen/logrus v1.4.2 => github.com/sirupsen/logrus v1.4.2
 
 require (
 	github.com/google/uuid v1.1.1
+	github.com/gorilla/mux v1.8.0
 	github.com/gorilla/websocket v1.4.1
 	github.com/sirupsen/logrus v1.4.2
 )

go.sum

@@ -1,13 +1,19 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/google/uuid v1.1.1 h1:Gkbcsh/GbpXz7lPftLA3P6TYMwjCLYm83jiFQZF/3gY=
 github.com/google/uuid v1.1.1/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/gorilla/mux v1.8.0 h1:i40aqfkR1h2SlN9hojwV5ZA91wcXFOvkdNIeFDP5koI=
+github.com/gorilla/mux v1.8.0/go.mod h1:DVbg23sWSpFRCP0SfiEN6jmj59UnW/n46BH5rLB71So=
 github.com/gorilla/websocket v1.4.1 h1:q7AeDBpnBk8AogcD4DSag/Ukw/KV+YhzLj2bP5HvKCM=
 github.com/gorilla/websocket v1.4.1/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
+github.com/konsorten/go-windows-terminal-sequences v1.0.1 h1:mweAR1A6xJ3oS2pRaGiHgQ4OO8tzTaLawm8vnODuwDk=
 github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/sirupsen/logrus v1.4.2 h1:SPIRibHv4MatM3XXNO2BJeFLZwZ2LvZgfQ5+UNI2im4=
 github.com/sirupsen/logrus v1.4.2/go.mod h1:tLMulIdttU9McNUspp0xgXVQah82FyeX6MwdIuYE2rE=
 github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.2.2 h1:bSDNvY7ZPG5RlJ8otE/7V6gMiyenm9RtJ7IUVIAoJ1w=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 golang.org/x/sys v0.0.0-20190422165155-953cdadca894 h1:Cz4ceDQGXuKRnVBDTS23GTn/pU5OE2C0WrNTOYK1Uuc=
 golang.org/x/sys v0.0.0-20190422165155-953cdadca894/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=