1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
|
package kubernetes
import (
"context"
"github.com/coredns/coredns/plugin"
"github.com/coredns/coredns/plugin/pkg/dnsutil"
"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) {
opt := plugin.Options{}
state := request.Request{W: w, Req: r, Context: ctx}
m := new(dns.Msg)
m.SetReply(r)
m.Authoritative, m.RecursionAvailable = true, true
zone := plugin.Zones(k.Zones).Matches(state.Name())
if zone == "" {
return plugin.NextOrFailure(k.Name(), k.Next, ctx, w, r)
}
state.Zone = zone
var (
records []dns.RR
extra []dns.RR
err error
)
switch state.QType() {
case dns.TypeA:
records, err = plugin.A(&k, zone, state, nil, opt)
case dns.TypeAAAA:
records, err = plugin.AAAA(&k, zone, state, nil, opt)
case dns.TypeTXT:
records, err = plugin.TXT(&k, zone, state, opt)
case dns.TypeCNAME:
records, err = plugin.CNAME(&k, zone, state, opt)
case dns.TypePTR:
records, err = plugin.PTR(&k, zone, state, opt)
case dns.TypeMX:
records, extra, err = plugin.MX(&k, zone, state, opt)
case dns.TypeSRV:
records, extra, err = plugin.SRV(&k, zone, state, opt)
case dns.TypeSOA:
records, err = plugin.SOA(&k, zone, state, opt)
case dns.TypeNS:
if state.Name() == zone {
records, extra, err = plugin.NS(&k, zone, state, opt)
break
}
fallthrough
case dns.TypeAXFR, dns.TypeIXFR:
k.Transfer(ctx, state)
default:
// Do a fake A lookup, so we can distinguish between NODATA and NXDOMAIN
_, err = plugin.A(&k, zone, state, nil, opt)
}
if k.IsNameError(err) {
if k.Fall.Through(state.Name()) {
return plugin.NextOrFailure(k.Name(), k.Next, ctx, w, r)
}
return plugin.BackendError(&k, zone, dns.RcodeNameError, state, nil /* err */, opt)
}
if err != nil {
return dns.RcodeServerFailure, err
}
if len(records) == 0 {
return plugin.BackendError(&k, zone, dns.RcodeSuccess, state, nil, opt)
}
m.Answer = append(m.Answer, records...)
m.Extra = append(m.Extra, extra...)
// TODO(miek): get rid of this by not adding dups in the first place, dnsutil.Append()?
m = dnsutil.Dedup(m)
state.SizeAndDo(m)
m, _ = state.Scrub(m)
w.WriteMsg(m)
return dns.RcodeSuccess, nil
}
// Name implements the Handler interface.
func (k Kubernetes) Name() string { return "kubernetes" }
|
