linux4life798

import 	CRAND "crypto/rand"

// GenMQTTClientID generates a random client id for mqtt
func GenMQTTClientID(prefix string) (string, error) {
	r, err := CRAND.Int(CRAND.Reader, new(big.Int).SetInt64(100000))
	if err != nil {
		return "", fmt.Errorf("Failed to generate MQTT client ID: %v", err)
	}
	return prefix + r.String(), nil
}

linux4life798

// isValidHex indicates if value is a proper hex strings that can be contained
// with the given number of bits
func isValidHex(value string, bits int) bool {
	str := strings.ToLower(value)
	precZeros := true
	bitcount := 0
	for _, c := range str {
		// Ensure the rune is a HEX character
		if !strings.Contains("0123456789abcdef", string(c)) {
			return false