[breaking] fix: validate sketch name

commands/sketch/new.go

@@ -18,6 +18,7 @@ package sketch
 import (
 	"context"
 	"errors"
+	"regexp"
 
 	"github.com/arduino/arduino-cli/arduino"
 	"github.com/arduino/arduino-cli/arduino/globals"
@@ -34,6 +35,10 @@ void loop() {
 }
 `)
 
+// sketchNameMaxLength could be part of the regex, but it's intentionally left out for clearer error reporting
+var sketchNameMaxLength = 63
+var sketchNameValidationRegex = regexp.MustCompile(`^[0-9a-zA-Z][0-9a-zA-Z_\.-]*$`)
+
 // NewSketch creates a new sketch via gRPC
 func NewSketch(ctx context.Context, req *rpc.NewSketchRequest) (*rpc.NewSketchResponse, error) {
 	var sketchesDir string
@@ -42,6 +47,11 @@ func NewSketch(ctx context.Context, req *rpc.NewSketchRequest) (*rpc.NewSketchRe
 	} else {
 		sketchesDir = configuration.Settings.GetString("directories.User")
 	}
+
+	if err := validateSketchName(req.SketchName); err != nil {
+		return nil, err
+	}
+
 	sketchDirPath := paths.New(sketchesDir).Join(req.SketchName)
 	if err := sketchDirPath.MkdirAll(); err != nil {
 		return nil, &arduino.CantCreateSketchError{Cause: err}
@@ -59,3 +69,20 @@ func NewSketch(ctx context.Context, req *rpc.NewSketchRequest) (*rpc.NewSketchRe
 
 	return &rpc.NewSketchResponse{MainFile: sketchMainFilePath.String()}, nil
 }
+
+func validateSketchName(name string) error {
+	if name == "" {
+		return &arduino.CantCreateSketchError{Cause: errors.New(tr("sketch name cannot be empty"))}
+	}
+	if len(name) > sketchNameMaxLength {
+		return &arduino.CantCreateSketchError{Cause: errors.New(tr("sketch name too long (%d characters). Maximum allowed length is %d",
+			len(name),
+			sketchNameMaxLength))}
+	}
+	if !sketchNameValidationRegex.MatchString(name) {
+		return &arduino.CantCreateSketchError{Cause: errors.New(tr("invalid sketch name \"%s\". Required pattern %s",
+			name,
+			sketchNameValidationRegex.String()))}
+	}
+	return nil
+}

commands/sketch/new_test.go

@@ -0,0 +1,82 @@
+package sketch
+
+import (
+	"context"
+	"testing"
+
+	"github.com/arduino/arduino-cli/rpc/cc/arduino/cli/commands/v1"
+	"github.com/stretchr/testify/require"
+)
+
+func Test_SketchNameWrongPattern(t *testing.T) {
+	invalidNames := []string{
+		"&",
+		"",
+		".hello",
+		"_hello",
+		"-hello",
+		"hello*",
+		"||||||||||||||",
+		",`hack[}attempt{];",
+	}
+	for _, name := range invalidNames {
+		_, err := NewSketch(context.Background(), &commands.NewSketchRequest{
+			SketchName: name,
+			SketchDir:  t.TempDir(),
+		})
+		require.NotNil(t, err)
+
+		require.Error(t, err, `Can't create sketch: invalid sketch name "%s". Required pattern %s`,
+			name,
+			sketchNameValidationRegex)
+	}
+}
+
+func Test_SketchNameEmpty(t *testing.T) {
+	emptyName := ""
+	_, err := NewSketch(context.Background(), &commands.NewSketchRequest{
+		SketchName: emptyName,
+		SketchDir:  t.TempDir(),
+	})
+	require.NotNil(t, err)
+
+	require.Error(t, err, `Can't create sketch: sketch name cannot be empty`)
+}
+
+func Test_SketchNameTooLong(t *testing.T) {
+	tooLongName := make([]byte, sketchNameMaxLength+1)
+	for i := range tooLongName {
+		tooLongName[i] = 'a'
+	}
+	_, err := NewSketch(context.Background(), &commands.NewSketchRequest{
+		SketchName: string(tooLongName),
+		SketchDir:  t.TempDir(),
+	})
+	require.NotNil(t, err)
+
+	require.Error(t, err, `Can't create sketch: sketch name too long (%d characters). Maximum allowed length is %d`,
+		len(tooLongName),
+		sketchNameMaxLength)
+}
+
+func Test_SketchNameOk(t *testing.T) {
+	lengthLimitName := make([]byte, sketchNameMaxLength)
+	for i := range lengthLimitName {
+		lengthLimitName[i] = 'a'
+	}
+	validNames := []string{
+		"h",
+		"h.ello",
+		"h..ello-world",
+		"h..ello-world.",
+		"hello_world__",
+		string(lengthLimitName),
+	}
+	for _, name := range validNames {
+		_, err := NewSketch(context.Background(), &commands.NewSketchRequest{
+			SketchName: name,
+			SketchDir:  t.TempDir(),
+		})
+		require.Nil(t, err)
+	}
+}

docs/UPGRADING.md

@@ -4,6 +4,14 @@ Here you can find a list of migration guides to handle breaking changes between
 
 ## 0.30.0
 
+### Sketch name validation
+
+The sketch name submitted via the `sketch new` command of the CLI or the gRPC command
+`cc.arduino.cli.commands.v1.NewSketch` are now validated. The applied rules follow the
+[sketch specifications](https://arduino.github.io/arduino-cli/dev/sketch-specification).
+
+Existing sketch names violating the new constraint need to be updated.
+
 ### `daemon` CLI command's `--ip` flag removal
 
 The `daemon` CLI command no longer allows to set a custom ip for the gRPC communication. Currently there is not enough

internal/cli/sketch/new.go

@@ -49,16 +49,33 @@ func initNewCommand() *cobra.Command {
 func runNewCommand(args []string, overwrite bool) {
 	logrus.Info("Executing `arduino-cli sketch new`")
 	// Trim to avoid issues if user creates a sketch adding the .ino extesion to the name
-	sketchName := args[0]
-	trimmedSketchName := strings.TrimSuffix(sketchName, globals.MainFileValidExtension)
-	sketchDirPath, err := paths.New(trimmedSketchName).Abs()
-	if err != nil {
-		feedback.Fatal(tr("Error creating sketch: %v", err), feedback.ErrGeneric)
+	inputSketchName := args[0]
+	trimmedSketchName := strings.TrimSuffix(inputSketchName, globals.MainFileValidExtension)
+
+	var sketchDir string
+	var sketchName string
+	var sketchDirPath *paths.Path
+	var err error
+
+	if trimmedSketchName == "" {
+		// `paths.New` returns nil with an empty string so `paths.Abs` panics.
+		// if the name is empty we rely on the "new" command to fail nicely later
+		// with the same logic in grpc and cli flows
+		sketchDir = ""
+		sketchName = ""
+	} else {
+		sketchDirPath, err = paths.New(trimmedSketchName).Abs()
+		if err != nil {
+			feedback.Fatal(tr("Error creating sketch: %v", err), feedback.ErrGeneric)
+		}
+		sketchDir = sketchDirPath.Parent().String()
+		sketchName = sketchDirPath.Base()
 	}
+
 	_, err = sk.NewSketch(context.Background(), &rpc.NewSketchRequest{
 		Instance:   nil,
-		SketchName: sketchDirPath.Base(),
-		SketchDir:  sketchDirPath.Parent().String(),
+		SketchName: sketchName,
+		SketchDir:  sketchDir,
 		Overwrite:  overwrite,
 	})
 	if err != nil {

internal/integrationtest/sketch/sketch_test.go

@@ -73,6 +73,16 @@ func TestSketchNew(t *testing.T) {
 	require.FileExists(t, currentSketchPath.Join(sketchName).String()+".ino")
 }
 
+func TestSketchNewEmptyName(t *testing.T) {
+	// testing that we fail nicely. It panicked in the past
+	env, cli := integrationtest.CreateArduinoCLIWithEnvironment(t)
+	defer env.CleanUp()
+
+	sketchName := ""
+	_, _, err := cli.Run("sketch", "new", sketchName)
+	require.Error(t, err, "Can't create sketch: sketch name cannot be empty")
+}
+
 func verifyZipContainsSketchExcludingBuildDir(t *testing.T, files []*zip.File) {
 	require.Len(t, files, 8)
 	require.Equal(t, paths.New("sketch_simple", "doc.txt").String(), files[0].Name)