Merge pull request #160 from IBM/validator

mounter args validator implementation

Author: ashimagarg27

cos-csi-mounter/server/server.go

@@ -97,12 +97,7 @@ func main() {
 
 func handleCosMount() gin.HandlerFunc {
 	return func(c *gin.Context) {
-		var request struct {
-			Path    string   `json:"path"`
-			Mounter string   `json:"mounter"`
-			Args    []string `json:"args"`
-		}
-
+		var request MountRequest
 		logger.Info("New mount request with values: ", zap.Any("Request:", request))
 
 		if err := c.BindJSON(&request); err != nil {
@@ -119,8 +114,16 @@ func handleCosMount() gin.HandlerFunc {
 			return
 		}
 
+		// validate mounter args
+		args, err := request.ParseMounterArgs()
+		if err != nil {
+			logger.Error("Failed to parse mounter args", zap.Any("mounter", request.Mounter), zap.Error(err))
+			c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid args for mounter"})
+			return
+		}
+
 		utils := mounterUtils.MounterOptsUtils{}
-		err := utils.FuseMount(request.Path, request.Mounter, request.Args)
+		err = utils.FuseMount(request.Path, request.Mounter, args)
 		if err != nil {
 			logger.Error("Mount Failed: ", zap.Error(err))
 			c.JSON(http.StatusBadRequest, gin.H{"error": "Mount Failed"})

cos-csi-mounter/server/utils.go

@@ -0,0 +1,135 @@
+package main
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"strings"
+)
+
+// MountRequest ...
+type MountRequest struct {
+	Path    string          `json:"path"`
+	Bucket  string          `json:"bucket"`
+	Mounter string          `json:"mounter"`
+	Args    json.RawMessage `json:"args"`
+}
+
+// MounterArgs ...
+type MounterArgs interface {
+	PopulateArgsSlice(string, string) ([]string, error)
+}
+type S3FSArgs struct {
+	URL                 string `json:"url,omitempty"`
+	PasswdFilePath      string `json:"passwd_file,omitempty"`
+	UsePathRequestStyle string `json:"use_path_request_style,omitempty"`
+	SigV2               string `json:"sigv2,omitempty"`
+	AllowOther          string `json:"allow_other,omitempty"`
+	MPUmask             string `json:"mp_umask,omitempty"`
+	EndPoint            string `json:"endpoint,omitempty"`
+	IBMIamAuth          string `json:"ibm_iam_auth,omitempty"`
+	IBMIamEndpoint      string `json:"ibm_iam_endpoint,omitempty"`
+	DefaultACL          string `json:"default_acl,omitempty"`
+}
+
+func (args S3FSArgs) PopulateArgsSlice(bucket, targetPath string) ([]string, error) {
+	// Marshal to JSON
+	raw, err := json.Marshal(args)
+	if err != nil {
+		return nil, err
+	}
+
+	// Unmarshal into map[string]string
+	var m map[string]string
+	if err := json.Unmarshal(raw, &m); err != nil {
+		return nil, err
+	}
+
+	// Convert to key=value slice
+	result := []string{bucket, targetPath}
+	for k, v := range m {
+		result = append(result, "-o")
+		if strings.ToLower(strings.TrimSpace(v)) == "true" {
+			result = append(result, fmt.Sprintf("%s", k)) // -o, key
+		} else {
+			result = append(result, fmt.Sprintf("%s=%v", k, v)) // -o, key=value
+		}
+	}
+
+	return result, nil // [bucket, path, -o, key1=value1, -o, key2=value2]
+}
+
+type RCloneArgs struct {
+	Endpoint  string `json:"endpoint,omitempty"`
+	BackupDir string `json:"backup-dir,omitempty"`
+	Bind      string `json:"bind,omitempty"`
+	BWLimit   string `json:"bwlimit,omitempty"`
+}
+
+func (args RCloneArgs) PopulateArgsSlice(bucket, targetPath string) ([]string, error) {
+	// Marshal to JSON
+	raw, err := json.Marshal(args)
+	if err != nil {
+		return nil, err
+	}
+
+	// Unmarshal into map[string]string
+	var m map[string]string
+	if err := json.Unmarshal(raw, &m); err != nil {
+		return nil, err
+	}
+
+	// Convert to key=value slice
+	result := []string{"mount", bucket, targetPath}
+	for k, v := range m {
+		result = append(result, fmt.Sprintf("--%s=%v", k, v)) // --key=value
+	}
+
+	return result, nil // [mount, bucket, path, --key1=value1, --key2=value2]
+}
+
+func strictDecodeForUnknownFields(data json.RawMessage, v interface{}) error {
+	dec := json.NewDecoder(bytes.NewReader(data))
+	dec.DisallowUnknownFields()
+	return dec.Decode(v)
+}
+
+func argsValidator(endpoint, targetPath string) error {
+	if !(strings.HasPrefix(endpoint, "https://") || strings.HasPrefix(endpoint, "http://")) {
+		return fmt.Errorf("Bad value for COS endpoint \"%v\": scheme is missing. "+
+			"Must be of the form http://<hostname> or https://<hostname>", endpoint)
+	}
+	if !(strings.HasPrefix(targetPath, "/var/data/kubelet/pods") || strings.HasPrefix(targetPath, "/var/lib/kubelet/pods")) {
+		return fmt.Errorf("Bad value for target path \"%v\"", targetPath)
+	}
+	return nil
+}
+
+// --- Parser for Mounter Arguments ---
+
+func (req *MountRequest) ParseMounterArgs() ([]string, error) {
+	switch req.Mounter {
+	case s3fs:
+		var args S3FSArgs
+		if err := strictDecodeForUnknownFields(req.Args, &args); err != nil {
+			return nil, fmt.Errorf("invalid s3fs args decode error: %w", err)
+		}
+		if err := argsValidator(args.URL, req.Path); err != nil {
+			return nil, fmt.Errorf("s3fs endpoint or target path validation failed: %w", err)
+		}
+		return args.PopulateArgsSlice(req.Bucket, req.Path)
+
+	case rclone:
+		var args RCloneArgs
+		if err := strictDecodeForUnknownFields(req.Args, &args); err != nil {
+			return nil, fmt.Errorf("invalid rclone args decode error: %w", err)
+		}
+		if err := argsValidator(args.Endpoint, req.Path); err != nil {
+			return nil, fmt.Errorf("rclone endpoint or target path validation failed: %w", err)
+		}
+		return args.PopulateArgsSlice(req.Bucket, req.Path)
+
+	default:
+		return nil, fmt.Errorf("unknown mounter: %s", req.Mounter)
+	}
+}