-
Notifications
You must be signed in to change notification settings - Fork 2.1k
/
server.go
125 lines (102 loc) · 3.33 KB
/
server.go
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
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
/*
Copyright 2020 The cert-manager Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package server
import (
"context"
"fmt"
"net"
"sync"
"time"
"github.com/miekg/dns"
logf "github.com/jetstack/cert-manager/pkg/logs"
)
const (
defaultTTL = 60
)
type BasicServer struct {
// Zones is a list of DNS zones that this server should accept responses
// for.
Zones []string
// Handler is an optional
Handler dns.Handler
// TSIG configuration options
// EnableTSIG enables TSIG support for the DNS server
// If true, both TSIGKeyName and TSIGKeySecret must be provided.
EnableTSIG bool
// TSIGKeyName to be used in responses when TSIG is enabled
TSIGKeyName string
// TSIGKeySecret to be used in responses when TSIG is enabled
TSIGKeySecret string
// TSIGZone is the DNS zone that should be used in TSIG responses
TSIGZone string
listenAddr string
server *dns.Server
}
// Run starts the test DNS server, binding to a random port on 127.0.0.1
func (b *BasicServer) Run(ctx context.Context) error {
return b.RunWithAddress(ctx, "127.0.0.1:0")
}
// RunWithAddress starts the test DNS server using the specified listen address.
func (b *BasicServer) RunWithAddress(ctx context.Context, listenAddr string) error {
log := logf.FromContext(ctx, "dnsBasicServer")
if listenAddr == "" {
return fmt.Errorf("listen address must be provided")
}
pc, err := net.ListenPacket("udp", listenAddr)
if err != nil {
return err
}
b.listenAddr = pc.LocalAddr().String()
log = log.WithValues("address", b.listenAddr)
log.V(logf.InfoLevel).Info("listening on UDP port")
b.server = &dns.Server{PacketConn: pc, ReadTimeout: time.Hour, WriteTimeout: time.Hour, MsgAcceptFunc: msgAcceptFunc}
if b.EnableTSIG {
log.V(logf.DebugLevel).Info("enabling TSIG support")
b.server.TsigSecret = map[string]string{b.TSIGKeyName: b.TSIGKeySecret}
}
if b.Handler == nil {
b.Handler = &rfc2136Handler{
log: log,
txtRecords: make(map[string][]string),
zones: b.Zones,
tsigZone: b.TSIGZone,
}
}
b.server.Handler = b.Handler
// Start the DNS server in a separate goroutine and wait for it to start
waitLock := sync.Mutex{}
waitLock.Lock()
b.server.NotifyStartedFunc = waitLock.Unlock
go func() {
log.V(logf.DebugLevel).Info("starting DNS server")
b.server.ActivateAndServe()
log.V(logf.DebugLevel).Info("DNS server exited")
pc.Close()
}()
waitLock.Lock()
defer waitLock.Unlock()
return nil
}
func (b *BasicServer) ListenAddr() string {
return b.listenAddr
}
func (b *BasicServer) Shutdown() error {
return b.server.Shutdown()
}
func msgAcceptFunc(dh dns.Header) dns.MsgAcceptAction {
// the miekg/dns message accept function disallows rfc2136 headers
// this function replaces that behaviour to always accept the request
// since this is always running in the controlled environment of tests
// it should not be an issue
return dns.MsgAccept
}