if len(suites) == 0 {
		return nil
	}
	ret := make([]string, 0, len(suites))
	validCiphers := sets.New[string]()
	for _, s := range suites {
		if IsValidCipherSuite(s) {
			if !validCiphers.InsertContains(s) {
				ret = append(ret, s)
			} else if log.DebugEnabled() {
				log.Debugf("ignoring duplicated cipherSuite: %q", s)
			}
		} else if log.DebugEnabled() {