Add separate option to configure tls mode for permissions client

This is a (temporary) workaround for allowing to separately configure the
tls mode for the permissions client used by the decomposedfs storage. This
is needed for being able to use the ocis settings service as the permission
service untils ocis' go-micro based services are adapted for providing TLS
as well.

pkg/storage/utils/decomposedfs/decomposedfs.go

@@ -115,7 +115,7 @@ func NewDefault(m map[string]interface{}, bs tree.Blobstore) (storage.FS, error)
 
 	tp := tree.New(o.Root, o.TreeTimeAccounting, o.TreeSizeAccounting, lu, bs)
 
-	permissionsClient, err := pool.GetPermissionsClient(o.PermissionsSVC)
+	permissionsClient, err := pool.GetPermissionsClient(o.PermissionsSVC, pool.WithTLSMode(o.PermTLSMode))
 	if err != nil {
 		return nil, err
 	}

pkg/storage/utils/decomposedfs/options/options.go

@@ -22,6 +22,8 @@ import (
 	"path/filepath"
 	"strings"
 
+	"github.com/cs3org/reva/v2/pkg/rgrpc/todo/pool"
+	"github.com/cs3org/reva/v2/pkg/sharedconf"
 	"github.com/mitchellh/mapstructure"
 	"github.com/pkg/errors"
 )
@@ -47,7 +49,9 @@ type Options struct {
 	TreeSizeAccounting bool `mapstructure:"treesize_accounting"`
 
 	// permissions service to use when checking permissions
-	PermissionsSVC string `mapstructure:"permissionssvc"`
+	PermissionsSVC           string `mapstructure:"permissionssvc"`
+	PermissionsClientTLSMode string `mapstructure:"permissionssvc_tls_mode"`
+	PermTLSMode              pool.TLSMode
 
 	PersonalSpaceAliasTemplate string `mapstructure:"personalspacealias_template"`
 	GeneralSpaceAliasTemplate  string `mapstructure:"generalspacealias_template"`
@@ -84,5 +88,20 @@ func New(m map[string]interface{}) (*Options, error) {
 		o.GeneralSpaceAliasTemplate = "{{.SpaceType}}/{{.SpaceName | replace \" \" \"-\" | lower}}"
 	}
 
+	if o.PermissionsClientTLSMode != "" {
+		var err error
+		o.PermTLSMode, err = pool.StringToTLSMode(o.PermissionsClientTLSMode)
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		sharedOpt := sharedconf.GRPCClientOptions()
+		var err error
+
+		if o.PermTLSMode, err = pool.StringToTLSMode(sharedOpt.TLSMode); err != nil {
+			return nil, err
+		}
+	}
+
 	return o, nil
 }