func updateRecord(r dns.RR, q *dns.Question) {
var (
rr dns.RR
name string
rtype uint16
ttl uint32
ip net.IP
)
header := r.Header()
name = header.Name
rtype = header.Rrtype
ttl = header.Ttl
if _, ok := dns.IsDomainName(name); ok {
if header.Class == dns.ClassANY && header.Rdlength == 0 { // Delete record
deleteRecord(name, rtype)
} else { // Add record
rheader := dns.RR_Header{
Name: name,
Rrtype: rtype,
Class: dns.ClassINET,
Ttl: ttl,
}
if a, ok := r.(*dns.A); ok {
rrr, err := getRecord(name, rtype)
if err == nil {
rr = rrr.(*dns.A)
} else {
rr = new(dns.A)
}
ip = a.A
rr.(*dns.A).Hdr = rheader
rr.(*dns.A).A = ip
} else if a, ok := r.(*dns.AAAA); ok {
rrr, err := getRecord(name, rtype)
if err == nil {
rr = rrr.(*dns.AAAA)
} else {
rr = new(dns.AAAA)
}
ip = a.AAAA
rr.(*dns.AAAA).Hdr = rheader
rr.(*dns.AAAA).AAAA = ip
}
storeRecord(rr)
}
}
}
func getKey(domain string, rtype uint16) (r string, e error) {
if n, ok := dns.IsDomainName(domain); ok {
labels := dns.SplitDomainName(domain)
// Reverse domain, starting from top-level domain
var tmp string
for i := 0; i < int(math.Floor(float64(n/2))); i++ {
tmp = labels[i]
labels[i] = labels[n-1]
labels[n-1] = tmp
}
reverse_domain := strings.Join(labels, ".")
r = strings.Join([]string{reverse_domain, strconv.Itoa(int(rtype))}, "_")
} else {
e = errors.New("Invailid domain: " + domain)
log.Println(e.Error())
}
return r, e
}