test/app/dns/handlers.go

96 lines
3.3 KiB
Go

package dns
import (
"net"
"strings"
"time"
"github.com/zeevdiukman/test/app/helper"
miekgDNS "github.com/miekg/dns"
)
// HandleTypeNS handles DNS NS queries.
func (a *DNS) HandleTypeNS(w miekgDNS.ResponseWriter, r *miekgDNS.Msg) {
t := time.Now() // Start timer
msg := &miekgDNS.Msg{}
msg.SetReply(r) // Set reply message
q := r.Question[0] // Get question
domainName := helper.FtoD(q.Name) // Convert FQDN to domain name
ns := ""
if nsValue, ok := a.Records.TypeNS[domainName]; ok {
ns = nsValue // Get NS from records
} else {
ns = "default-ns.example.com." // Default NS if not found
}
RR_Header := miekgDNS.RR_Header{
Name: miekgDNS.Fqdn(domainName), // Set domain name
Rrtype: miekgDNS.TypeNS, // Set record type
Class: miekgDNS.ClassINET, // Set class
Ttl: 3600, // Set TTL
}
answer_typeNS := &miekgDNS.NS{
Hdr: RR_Header, // Set header
Ns: ns, // Set NS
}
msg.Authoritative = true // Set authoritative flag
msg.RecursionDesired = false // Set recursion desired flag
msg.SetRcode(r, miekgDNS.RcodeSuccess) // Set response code
msg.Answer = append(msg.Answer, answer_typeNS) // Add answer
tt := time.Since(t) // Calculate elapsed time
helper.P(tt, " => ", domainName) // Print elapsed time and domain name
w.WriteMsg(msg) // Write response
}
// HandleTypeA handles DNS Type A queries.
func (a *DNS) HandleTypeA(w miekgDNS.ResponseWriter, r *miekgDNS.Msg) {
useAlternateResolver := false
t := time.Now() // Start timer
msg := &miekgDNS.Msg{}
msg.SetReply(r) // Set reply message
q := r.Question[0] // Get question
domainName := helper.FtoD(q.Name) // Convert FQDN to domain name
ip := ""
if ipValue, ok := a.Records.TypeA[domainName]; ok {
ip = ipValue // Get IP from records
} else {
dSlices := strings.Split(domainName, ".") // Split domain name
// Check if wildcard
if len(dSlices) > 2 {
name := dSlices[len(dSlices)-2]
tld := dSlices[len(dSlices)-1]
cname := name + "." + tld
wildCard := "*." + cname
if ipValue, ok := a.Records.TypeA[wildCard]; ok {
ip = ipValue // Get IP from wildcard record
} else {
useAlternateResolver = true // Use alternate resolver
}
} else {
useAlternateResolver = true // Use alternate resolver
}
if useAlternateResolver {
ip = a.Resolver.Lookup(domainName) // Lookup IP using resolver
}
}
RR_Header := miekgDNS.RR_Header{
Name: miekgDNS.Fqdn(domainName), // Set domain name
Rrtype: miekgDNS.TypeA, // Set record type
Class: miekgDNS.ClassINET, // Set class
Ttl: 3600, // Set TTL
}
answer_typeA := &miekgDNS.A{
Hdr: RR_Header, // Set header
A: net.ParseIP(ip).To4(), // Set IP address
}
msg.Authoritative = true // Set authoritative flag
msg.RecursionDesired = false // Set recursion desired flag
msg.SetRcode(r, miekgDNS.RcodeSuccess) // Set response code
msg.Answer = append(msg.Answer, answer_typeA) // Add answer
tt := time.Since(t) // Calculate elapsed time
helper.P(tt, " => ", domainName) // Print elapsed time and domain name
w.WriteMsg(msg) // Write response
}