rbd: set SnapshotGroupID on each Snapshot of a VolumeGroupSnapshot

Without the SnapshotGroupID in the Snapshot object, Kubernetes CSI does
not know that the Snapshot belongs to a group. In that case, it allows
the deletion of the Snapshot, which should be denied.

Signed-off-by: Niels de Vos <ndevos@ibm.com>

internal/rbd/group/group_snapshot.go

@@ -155,6 +155,12 @@ func NewVolumeGroupSnapshot(
 		}
 
 		volumeMap[handle] = name
+
+		// store the CSI ID of the group in the snapshot attributes
+		snapErr = snapshot.SetVolumeGroup(ctx, creds, vgs.id)
+		if snapErr != nil {
+			return nil, fmt.Errorf("failed to set volume group ID %q for snapshot %q: %w", vgs.id, name, snapErr)
+		}
 	}
 
 	j, err := vgs.getJournal(ctx)

internal/rbd/manager.go

@@ -212,11 +212,6 @@ func (mgr *rbdManager) GetSnapshotByID(ctx context.Context, id string) (types.Sn
 		}
 	}
 
-	// FIXME: The snapshot will have RbdImageName set to the image that was
-	// used as source. This is not correct for group snapshots images, and
-	// need to be fixed. See rbdVolume.NewSnapshotByID() for more details.
-	snapshot.RbdImageName = snapshot.RbdSnapName
-
 	return snapshot, nil
 }
 

internal/rbd/rbd_util.go

@@ -191,6 +191,9 @@ type rbdSnapshot struct {
 	// RbdSnapName is the name of the RBD snapshot backing this rbdSnapshot
 	SourceVolumeID string
 	RbdSnapName    string
+
+	// groupID is the CSI volume group ID where this snapshot belongs to
+	groupID string
 }
 
 // imageFeature represents required image features and value.
@@ -1054,6 +1057,15 @@ func genSnapFromSnapID(
 		}
 	}
 
+	if imageAttributes.GroupID != "" {
+		rbdSnap.groupID = imageAttributes.GroupID
+		// FIXME: The snapshot will have RbdImageName set to the image
+		// that was used as source. This is not correct for group
+		// snapshots images, and need to be fixed. See
+		// rbdVolume.NewSnapshotByID() for more details.
+		rbdSnap.RbdImageName = rbdSnap.RbdSnapName
+	}
+
 	err = rbdSnap.Connect(cr)
 	if err != nil {
 		return rbdSnap, fmt.Errorf("failed to connect to %q: %w",

internal/rbd/snapshot.go

@@ -158,6 +158,7 @@ func (rbdSnap *rbdSnapshot) ToCSI(ctx context.Context) (*csi.Snapshot, error) {
 		SourceVolumeId:  rbdSnap.SourceVolumeID,
 		CreationTime:    timestamppb.New(*created),
 		ReadyToUse:      true,
+		GroupSnapshotId: rbdSnap.groupID,
 	}, nil
 }
 
@@ -315,3 +316,26 @@ func (rv *rbdVolume) NewSnapshotByID(
 
 	return snap, nil
 }
+
+func (rbdSnap *rbdSnapshot) SetVolumeGroup(ctx context.Context, cr *util.Credentials, groupID string) error {
+	vi := util.CSIIdentifier{}
+	err := vi.DecomposeCSIID(rbdSnap.VolID)
+	if err != nil {
+		return err
+	}
+
+	j, err := snapJournal.Connect(rbdSnap.Monitors, rbdSnap.RadosNamespace, cr)
+	if err != nil {
+		return fmt.Errorf("snapshot %q failed to connect to journal: %w", rbdSnap, err)
+	}
+	defer j.Destroy()
+
+	err = j.StoreGroupID(ctx, rbdSnap.Pool, vi.ObjectUUID, groupID)
+	if err != nil {
+		return fmt.Errorf("failed to set volume group ID for snapshot %q: %w", rbdSnap, err)
+	}
+
+	rbdSnap.groupID = groupID
+
+	return nil
+}

internal/rbd/types/snapshot.go

@@ -21,6 +21,8 @@ import (
 	"time"
 
 	"github.com/container-storage-interface/spec/lib/go/csi"
+
+	"github.com/ceph/ceph-csi/internal/util"
 )
 
 type Snapshot interface {
@@ -35,4 +37,7 @@ type Snapshot interface {
 	ToCSI(ctx context.Context) (*csi.Snapshot, error)
 
 	GetCreationTime(ctx context.Context) (*time.Time, error)
+
+	// SetVolumeGroup sets the CSI volume group ID in the snapshot.
+	SetVolumeGroup(ctx context.Context, creds *util.Credentials, vgID string) error
 }