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
|
package etcd
import (
"context"
"github.com/coredns/coredns/plugin"
"github.com/coredns/coredns/request"
"github.com/miekg/dns"
)
// ServeDNS implements the plugin.Handler interface.
func (e *Etcd) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
opt := plugin.Options{}
state := request.Request{W: w, Req: r}
zone := plugin.Zones(e.Zones).Matches(state.Name())
if zone == "" {
return plugin.NextOrFailure(e.Name(), e.Next, ctx, w, r)
}
var (
records, extra []dns.RR
err error
)
switch state.QType() {
case dns.TypeA:
records, err = plugin.A(ctx, e, zone, state, nil, opt)
case dns.TypeAAAA:
records, err = plugin.AAAA(ctx, e, zone, state, nil, opt)
case dns.TypeTXT:
records, err = plugin.TXT(ctx, e, zone, state, nil, opt)
case dns.TypeCNAME:
records, err = plugin.CNAME(ctx, e, zone, state, opt)
case dns.TypePTR:
records, err = plugin.PTR(ctx, e, zone, state, opt)
case dns.TypeMX:
records, extra, err = plugin.MX(ctx, e, zone, state, opt)
case dns.TypeSRV:
records, extra, err = plugin.SRV(ctx, e, zone, state, opt)
case dns.TypeSOA:
records, err = plugin.SOA(ctx, e, zone, state, opt)
case dns.TypeNS:
if state.Name() == zone {
records, extra, err = plugin.NS(ctx, e, zone, state, opt)
break
}
fallthrough
default:
// Do a fake A lookup, so we can distinguish between NODATA and NXDOMAIN
_, err = plugin.A(ctx, e, zone, state, nil, opt)
}
if err != nil && e.IsNameError(err) {
if e.Fall.Through(state.Name()) {
return plugin.NextOrFailure(e.Name(), e.Next, ctx, w, r)
}
// Make err nil when returning here, so we don't log spam for NXDOMAIN.
return plugin.BackendError(ctx, e, zone, dns.RcodeNameError, state, nil /* err */, opt)
}
if err != nil {
return plugin.BackendError(ctx, e, zone, dns.RcodeServerFailure, state, err, opt)
}
if len(records) == 0 {
return plugin.BackendError(ctx, e, zone, dns.RcodeSuccess, state, err, opt)
}
m := new(dns.Msg)
m.SetReply(r)
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 (e *Etcd) Name() string { return "etcd" }
|
