rc: methods marked as AuthRequired need auth unless --rc-no-auth

Methods which can read or mutate external storage will require
authorisation - enforce this.  This can be overidden by `--rc-no-auth`.

fs/rc/internal.go

@@ -17,6 +17,16 @@ func init() {
 		Help: `
 This echoes the input parameters to the output parameters for testing
 purposes.  It can be used to check that rclone is still alive and to
+check that parameter passing is working properly.`,
+	})
+	Add(Call{
+		Path:         "rc/noopauth",
+		AuthRequired: true,
+		Fn:           rcNoop,
+		Title:        "Echo the input to the output parameters requiring auth",
+		Help: `
+This echoes the input parameters to the output parameters for testing
+purposes.  It can be used to check that rclone is still alive and to
 check that parameter passing is working properly.`,
 	})
 	Add(Call{

fs/rc/rc.go

@@ -21,6 +21,7 @@ type Options struct {
 	Enabled     bool   // set to enable the server
 	Serve       bool   // set to serve files from remotes
 	Files       string // set to enable serving files locally
+	NoAuth      bool   // set to disable auth checks on AuthRequired methods
 }
 
 // DefaultOpt is the default values used for Options

fs/rc/rcflags/rcflags.go

@@ -19,5 +19,6 @@ func AddFlags(flagSet *pflag.FlagSet) {
 	flags.BoolVarP(flagSet, &Opt.Enabled, "rc", "", false, "Enable the remote control server.")
 	flags.StringVarP(flagSet, &Opt.Files, "rc-files", "", "", "Path to local files to serve on the HTTP server.")
 	flags.BoolVarP(flagSet, &Opt.Serve, "rc-serve", "", false, "Enable the serving of remote objects.")
+	flags.BoolVarP(flagSet, &Opt.NoAuth, "rc-no-auth", "", false, "Don't require auth for certain methods.")
 	httpflags.AddFlagsPrefix(flagSet, "rc-", &Opt.HTTPOptions)
 }

fs/rc/rcserver/rcserver.go

@@ -159,6 +159,12 @@ func (s *Server) handlePost(w http.ResponseWriter, r *http.Request, path string)
 		return
 	}
 
+	// Check to see if it requires authorisation
+	if !s.opt.NoAuth && call.AuthRequired && !s.UsingAuth() {
+		writeError(path, in, w, errors.Errorf("authentication must be set up on the rc server to use %q or the --rc-no-auth flag must be in use", path), http.StatusForbidden)
+		return
+	}
+
 	// Check to see if it is async or not
 	isAsync, err := in.GetBool("_async")
 	if rc.NotErrParamNotFound(err) {

fs/rc/rcserver/rcserver_test.go

@@ -537,6 +537,65 @@ func TestNoServe(t *testing.T) {
 	testServer(t, tests, &opt)
 }
 
+func TestAuthRequired(t *testing.T) {
+	tests := []testRun{{
+		Name:        "auth",
+		URL:         "rc/noopauth",
+		Method:      "POST",
+		Body:        `{}`,
+		ContentType: "application/javascript",
+		Status:      http.StatusForbidden,
+		Expected: `{
+	"error": "authentication must be set up on the rc server to use \"rc/noopauth\" or the --rc-no-auth flag must be in use",
+	"input": {},
+	"path": "rc/noopauth",
+	"status": 403
+}
+`,
+	}}
+	opt := newTestOpt()
+	opt.Serve = false
+	opt.Files = ""
+	opt.NoAuth = false
+	testServer(t, tests, &opt)
+}
+
+func TestNoAuth(t *testing.T) {
+	tests := []testRun{{
+		Name:        "auth",
+		URL:         "rc/noopauth",
+		Method:      "POST",
+		Body:        `{}`,
+		ContentType: "application/javascript",
+		Status:      http.StatusOK,
+		Expected:    "{}\n",
+	}}
+	opt := newTestOpt()
+	opt.Serve = false
+	opt.Files = ""
+	opt.NoAuth = true
+	testServer(t, tests, &opt)
+}
+
+func TestWithUserPass(t *testing.T) {
+	tests := []testRun{{
+		Name:        "auth",
+		URL:         "rc/noopauth",
+		Method:      "POST",
+		Body:        `{}`,
+		ContentType: "application/javascript",
+		Status:      http.StatusOK,
+		Expected:    "{}\n",
+	}}
+	opt := newTestOpt()
+	opt.Serve = false
+	opt.Files = ""
+	opt.NoAuth = false
+	opt.HTTPOptions.BasicUser = "user"
+	opt.HTTPOptions.BasicPass = "pass"
+	testServer(t, tests, &opt)
+}
+
 func TestRCAsync(t *testing.T) {
 	tests := []testRun{{
 		Name:        "ok",

fs/rc/registry.go

@@ -16,10 +16,11 @@ type Func func(in Params) (out Params, err error)
 // Call defines info about a remote control function and is used in
 // the Add function to create new entry points.
 type Call struct {
-	Path  string // path to activate this RC
-	Fn    Func   `json:"-"` // function to call
-	Title string // help for the function
-	Help  string // multi-line markdown formatted help
+	Path         string // path to activate this RC
+	Fn           Func   `json:"-"` // function to call
+	Title        string // help for the function
+	AuthRequired bool   // if set then this call requires authorisation to be set
+	Help         string // multi-line markdown formatted help
 }
 
 // Registry holds the list of all the registered remote control functions