66dc74caeb
Persist the TC bit to client response for truncated CNAME lookups. Signed-off-by: Chris O'Haver <cohaver@infoblox.com>
94 lines
2.8 KiB
Go
94 lines
2.8 KiB
Go
package kubernetes
|
|
|
|
import (
|
|
"context"
|
|
|
|
"github.com/coredns/coredns/plugin"
|
|
"github.com/coredns/coredns/request"
|
|
|
|
"github.com/miekg/dns"
|
|
)
|
|
|
|
// ServeDNS implements the plugin.Handler interface.
|
|
func (k Kubernetes) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
|
|
state := request.Request{W: w, Req: r}
|
|
|
|
qname := state.QName()
|
|
zone := plugin.Zones(k.Zones).Matches(qname)
|
|
if zone == "" {
|
|
return plugin.NextOrFailure(k.Name(), k.Next, ctx, w, r)
|
|
}
|
|
zone = qname[len(qname)-len(zone):] // maintain case of original query
|
|
state.Zone = zone
|
|
|
|
var (
|
|
records []dns.RR
|
|
extra []dns.RR
|
|
truncated bool
|
|
err error
|
|
)
|
|
|
|
switch state.QType() {
|
|
case dns.TypeA:
|
|
records, truncated, err = plugin.A(ctx, &k, zone, state, nil, plugin.Options{})
|
|
case dns.TypeAAAA:
|
|
records, truncated, err = plugin.AAAA(ctx, &k, zone, state, nil, plugin.Options{})
|
|
case dns.TypeTXT:
|
|
records, truncated, err = plugin.TXT(ctx, &k, zone, state, nil, plugin.Options{})
|
|
case dns.TypeCNAME:
|
|
records, err = plugin.CNAME(ctx, &k, zone, state, plugin.Options{})
|
|
case dns.TypePTR:
|
|
records, err = plugin.PTR(ctx, &k, zone, state, plugin.Options{})
|
|
case dns.TypeMX:
|
|
records, extra, err = plugin.MX(ctx, &k, zone, state, plugin.Options{})
|
|
case dns.TypeSRV:
|
|
records, extra, err = plugin.SRV(ctx, &k, zone, state, plugin.Options{})
|
|
case dns.TypeSOA:
|
|
if qname == zone {
|
|
records, err = plugin.SOA(ctx, &k, zone, state, plugin.Options{})
|
|
}
|
|
case dns.TypeAXFR, dns.TypeIXFR:
|
|
return dns.RcodeRefused, nil
|
|
case dns.TypeNS:
|
|
if state.Name() == zone {
|
|
records, extra, err = plugin.NS(ctx, &k, zone, state, plugin.Options{})
|
|
break
|
|
}
|
|
fallthrough
|
|
default:
|
|
// Do a fake A lookup, so we can distinguish between NODATA and NXDOMAIN
|
|
fake := state.NewWithQuestion(state.QName(), dns.TypeA)
|
|
fake.Zone = state.Zone
|
|
_, _, err = plugin.A(ctx, &k, zone, fake, nil, plugin.Options{})
|
|
}
|
|
|
|
if k.IsNameError(err) {
|
|
if k.Fall.Through(state.Name()) {
|
|
return plugin.NextOrFailure(k.Name(), k.Next, ctx, w, r)
|
|
}
|
|
if !k.APIConn.HasSynced() {
|
|
// If we haven't synchronized with the kubernetes cluster, return server failure
|
|
return plugin.BackendError(ctx, &k, zone, dns.RcodeServerFailure, state, nil /* err */, plugin.Options{})
|
|
}
|
|
return plugin.BackendError(ctx, &k, zone, dns.RcodeNameError, state, nil /* err */, plugin.Options{})
|
|
}
|
|
if err != nil {
|
|
return dns.RcodeServerFailure, err
|
|
}
|
|
|
|
if len(records) == 0 {
|
|
return plugin.BackendError(ctx, &k, zone, dns.RcodeSuccess, state, nil, plugin.Options{})
|
|
}
|
|
|
|
m := new(dns.Msg)
|
|
m.SetReply(r)
|
|
m.Truncated = truncated
|
|
m.Authoritative = true
|
|
m.Answer = append(m.Answer, records...)
|
|
m.Extra = append(m.Extra, extra...)
|
|
w.WriteMsg(m)
|
|
return dns.RcodeSuccess, nil
|
|
}
|
|
|
|
// Name implements the Handler interface.
|
|
func (k Kubernetes) Name() string { return "kubernetes" }
|