drivers/azure/util.go
func parseSecurityRuleProtocol(proto string) (network.SecurityRuleProtocol, error) {
	switch strings.ToLower(proto) {
	case "tcp":
		return network.TCP, nil
	case "udp":
		return network.UDP, nil
	case "*":
		return network.Asterisk, nil
	default:
		return "", fmt.Errorf("invalid protocol %s", proto)
	}
}
func parseSecurityRuleProtocol(proto string) (network.SecurityRuleProtocol, error) {
	switch strings.ToLower(proto) {
	case "tcp":
		return network.TCP, nil
	case "udp":
		return network.UDP, nil
	case "*":
		return network.Asterisk, nil
	default:
		return "", fmt.Errorf("invalid protocol %s", proto)
	}
}
// parseSecurityRuleProtocol parses a protocol string into a network.SecurityRuleProtocol
// and returns error if the protocol is not supported