// from the metadata using the KMS and returns the decrypted object
// keys.
//
// The metadata, buckets and objects slices must have the same length.
func (s3 sses3) UnsealObjectKeys(ctx context.Context, k *kms.KMS, metadata []map[string]string, buckets, objects []string) ([]ObjectKey, error) {
	if k == nil {
		return nil, Errorf("KMS not configured")
	}