acme-dns/dns.go
2016-11-13 20:35:11 +02:00

106 lines
2.8 KiB
Go

package main
import (
"fmt"
"github.com/miekg/dns"
"strings"
"time"
)
func readQuery(m *dns.Msg) {
for _, que := range m.Question {
if rr, rc, err := answer(que); err == nil {
m.MsgHdr.Rcode = rc
for _, r := range rr {
m.Answer = append(m.Answer, r)
}
}
}
}
func answerTXT(q dns.Question) ([]dns.RR, int, error) {
var ra []dns.RR
var rcode int = dns.RcodeNameError
var domain string = strings.ToLower(q.Name)
atxt, err := DB.GetByDomain(SanitizeDomainQuestion(domain))
if err != nil {
log.Errorf("Error while trying to get record [%v]", err)
return ra, dns.RcodeNameError, err
}
for _, v := range atxt {
if len(v.Value) > 0 {
r := new(dns.TXT)
r.Hdr = dns.RR_Header{Name: domain, Rrtype: dns.TypeTXT, Class: dns.ClassINET, Ttl: 1}
r.Txt = append(r.Txt, v.Value)
ra = append(ra, r)
rcode = dns.RcodeSuccess
}
}
log.Debugf("Answering TXT question for domain [%s]", domain)
return ra, rcode, nil
}
func answer(q dns.Question) ([]dns.RR, int, error) {
if q.Qtype == dns.TypeTXT {
return answerTXT(q)
}
var r []dns.RR
var rcode int = dns.RcodeSuccess
var domain string = strings.ToLower(q.Name)
var rtype uint16 = q.Qtype
r, ok := RR.Records[rtype][domain]
if !ok {
rcode = dns.RcodeNameError
}
log.Debugf("Answering [%s] question for domain [%s] with rcode [%s]", dns.TypeToString[rtype], domain, dns.RcodeToString[rcode])
return r, rcode, nil
}
func handleRequest(w dns.ResponseWriter, r *dns.Msg) {
m := new(dns.Msg)
m.SetReply(r)
if r.Opcode == dns.OpcodeQuery {
readQuery(m)
}
w.WriteMsg(m)
}
// Parse config records
func (r *Records) Parse(recs []string) {
rrmap := make(map[uint16]map[string][]dns.RR)
for _, v := range recs {
rr, err := dns.NewRR(strings.ToLower(v))
if err != nil {
log.Errorf("Could not parse RR from config: [%v] for RR: [%s]", err, v)
continue
}
// Add parsed RR to the list
rrmap = AppendRR(rrmap, rr)
}
// Create serial
serial := time.Now().Format("2006010215")
// Add SOA
SOAstring := fmt.Sprintf("%s. SOA %s. %s. %s 28800 7200 604800 86400", strings.ToLower(DnsConf.General.Domain), strings.ToLower(DnsConf.General.Nsname), strings.ToLower(DnsConf.General.Nsadmin), serial)
soarr, err := dns.NewRR(SOAstring)
if err != nil {
log.Errorf("Error [%v] while trying to add SOA record: [%s]", err, SOAstring)
} else {
rrmap = AppendRR(rrmap, soarr)
}
r.Records = rrmap
}
func AppendRR(rrmap map[uint16]map[string][]dns.RR, rr dns.RR) map[uint16]map[string][]dns.RR {
_, ok := rrmap[rr.Header().Rrtype]
if !ok {
newrr := make(map[string][]dns.RR)
rrmap[rr.Header().Rrtype] = newrr
}
rrmap[rr.Header().Rrtype][rr.Header().Name] = append(rrmap[rr.Header().Rrtype][rr.Header().Name], rr)
log.Debugf("Adding new record of type [%s] for domain [%s]", dns.TypeToString[rr.Header().Rrtype], rr.Header().Name)
return rrmap
}