// Lookup user DN
	lookupRes, err := l.LDAP.LookupUsername(conn, username)
	if err != nil {
		errRet := fmt.Errorf("Unable to find user DN: %w", err)
		return nil, nil, errRet
	}

	groups, err := l.LDAP.SearchForUserGroups(conn, username, lookupRes.ActualDN)
	if err != nil {
		return nil, nil, err
	}

	return lookupRes, groups, nil
}

// GetValidatedDNForUsername checks if the given username exists in the LDAP directory.