handle NS

This commit is contained in:
m5r 2022-10-29 10:10:54 +02:00
parent 62ebedb848
commit 01de8a29bc
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@ -19,38 +19,87 @@ type Xip struct {
}
var (
flyRegion = os.Getenv("FLY_REGION")
dottedIpV4Regex = regexp.MustCompile(`(?:^|(?:[\w\d])+\.)(((25[0-5]|(2[0-4]|1\d|[1-9]|)\d)\.?\b){4})($|[.-])`)
dashedIpV4Regex = regexp.MustCompile(`(?:^|(?:[\w\d])+\.)(((25[0-5]|(2[0-4]|1\d|[1-9]|)\d)\-?\b){4})($|[.-])`)
flyRegion = os.Getenv("FLY_REGION")
dottedIpV4Regex = regexp.MustCompile(`(?:^|(?:[\w\d])+\.)(((25[0-5]|(2[0-4]|1\d|[1-9]|)\d)\.?\b){4})($|[.-])`)
dashedIpV4Regex = regexp.MustCompile(`(?:^|(?:[\w\d])+\.)(((25[0-5]|(2[0-4]|1\d|[1-9]|)\d)\-?\b){4})($|[.-])`)
hardcodedDomains = map[string]net.IP{
"ns.local-ip.sh.": net.IPv4(137, 66, 38, 214),
"ns1.local-ip.sh.": net.IPv4(137, 66, 38, 214),
"ns2.local-ip.sh.": net.IPv4(137, 66, 38, 214),
}
)
func (xip *Xip) fqdnToA(fqdn string) *dns.A {
var ipV4Address net.IP
if hardcodedDomains[strings.ToLower(fqdn)] != nil {
ipV4Address = hardcodedDomains[strings.ToLower(fqdn)]
} else {
for _, ipV4RE := range []*regexp.Regexp{dashedIpV4Regex, dottedIpV4Regex} {
if ipV4RE.MatchString(fqdn) {
match := ipV4RE.FindStringSubmatch(fqdn)[1]
match = strings.ReplaceAll(match, "-", ".")
ipV4Address = net.ParseIP(match).To4()
break
}
}
}
if ipV4Address == nil {
return nil
}
return &dns.A{
Hdr: dns.RR_Header{
// Ttl: uint32((time.Hour * 24 * 7).Seconds()),
Ttl: uint32((time.Second * 10).Seconds()),
Name: fqdn,
Rrtype: dns.TypeA,
Class: dns.ClassINET,
},
A: ipV4Address,
}
}
func (xip *Xip) handleA(question dns.Question, message *dns.Msg) {
fqdn := question.Name
record := xip.fqdnToA(fqdn)
for _, ipV4RE := range []*regexp.Regexp{dashedIpV4Regex, dottedIpV4Regex} {
if ipV4RE.MatchString(fqdn) {
match := ipV4RE.FindStringSubmatch(fqdn)[1]
match = strings.ReplaceAll(match, "-", ".")
ipV4Address := net.ParseIP(match).To4()
if ipV4Address == nil {
message.Rcode = dns.RcodeNameError
message.Ns = append(message.Ns, xip.SOARecord(question))
return
}
if record == nil {
message.Rcode = dns.RcodeNameError
message.Ns = append(message.Ns, xip.SOARecord(question))
return
}
record := &dns.A{
Hdr: dns.RR_Header{
// Ttl: uint32((time.Hour * 24 * 7).Seconds()),
Ttl: uint32((time.Second * 10).Seconds()),
Name: fqdn,
Rrtype: dns.TypeA,
Class: dns.ClassINET,
},
A: ipV4Address,
}
log.Printf("(%s) %s => %s\n", flyRegion, fqdn, ipV4Address)
message.Answer = append(message.Answer, record)
}
log.Printf("(%s) %s => %s\n", flyRegion, fqdn, record.A)
message.Answer = append(message.Answer, record)
}
func (xip *Xip) handleNS(question dns.Question, message *dns.Msg) {
fqdn := question.Name
nameServers := []*dns.NS{}
additionals := []*dns.A{}
for _, ns := range xip.NameServers {
nameServers = append(nameServers, &dns.NS{
Hdr: dns.RR_Header{
// Ttl: uint32((time.Hour * 24 * 7).Seconds()),
Ttl: uint32((time.Second * 10).Seconds()),
Name: fqdn,
Rrtype: dns.TypeNS,
Class: dns.ClassINET,
},
Ns: ns.Ns,
})
additionals = append(additionals, xip.fqdnToA(ns.Ns))
}
for _, record := range nameServers {
message.Answer = append(message.Answer, record)
}
for _, record := range additionals {
message.Extra = append(message.Extra, record)
}
}
@ -64,8 +113,8 @@ func (xip *Xip) SOARecord(question dns.Question) *dns.SOA {
Ttl: uint32((time.Second * 10).Seconds()),
Rdlength: 0,
}
soa.Ns = "ns.local-ip.dev."
soa.Mbox = "admin.local-ip.dev."
soa.Ns = "ns.local-ip.sh."
soa.Mbox = "admin.local-ip.sh."
soa.Serial = 2022102800
// soa.Refresh = uint32((time.Minute * 15).Seconds())
soa.Refresh = uint32((time.Second * 10).Seconds())
@ -81,9 +130,14 @@ func (xip *Xip) SOARecord(question dns.Question) *dns.SOA {
func (xip *Xip) handleQuery(message *dns.Msg) {
for _, question := range message.Question {
log.Printf("name: %s\n", question.Name)
log.Printf("class: %d\n", question.Qclass)
log.Printf("type: %d\n", question.Qtype)
switch question.Qtype {
case dns.TypeA:
xip.handleA(question, message)
case dns.TypeNS:
xip.handleNS(question, message)
}
}
}