/
publisher.go
238 lines (199 loc) · 6.59 KB
/
publisher.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
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
/*
Copyright 2018 The Kubernetes 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 rootcacertpublisher
import (
"context"
"fmt"
"reflect"
"time"
v1 "k8s.io/api/core/v1"
apierrors "k8s.io/apimachinery/pkg/api/errors"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
utilruntime "k8s.io/apimachinery/pkg/util/runtime"
"k8s.io/apimachinery/pkg/util/wait"
coreinformers "k8s.io/client-go/informers/core/v1"
clientset "k8s.io/client-go/kubernetes"
corelisters "k8s.io/client-go/listers/core/v1"
"k8s.io/client-go/tools/cache"
"k8s.io/client-go/util/workqueue"
"k8s.io/klog/v2"
)
// RootCACertConfigMapName is name of the configmap which stores certificates
// to access api-server
const (
RootCACertConfigMapName = "kube-root-ca.crt"
DescriptionAnnotation = "kubernetes.io/description"
Description = "Contains a CA bundle that can be used to verify the kube-apiserver when using internal endpoints such as the internal service IP or kubernetes.default.svc. " +
"No other usage is guaranteed across distributions of Kubernetes clusters."
)
func init() {
registerMetrics()
}
// NewPublisher construct a new controller which would manage the configmap
// which stores certificates in each namespace. It will make sure certificate
// configmap exists in each namespace.
func NewPublisher(cmInformer coreinformers.ConfigMapInformer, nsInformer coreinformers.NamespaceInformer, cl clientset.Interface, rootCA []byte) (*Publisher, error) {
e := &Publisher{
client: cl,
rootCA: rootCA,
queue: workqueue.NewNamedRateLimitingQueue(workqueue.DefaultControllerRateLimiter(), "root_ca_cert_publisher"),
}
cmInformer.Informer().AddEventHandler(cache.ResourceEventHandlerFuncs{
DeleteFunc: e.configMapDeleted,
UpdateFunc: e.configMapUpdated,
})
e.cmLister = cmInformer.Lister()
e.cmListerSynced = cmInformer.Informer().HasSynced
nsInformer.Informer().AddEventHandler(cache.ResourceEventHandlerFuncs{
AddFunc: e.namespaceAdded,
UpdateFunc: e.namespaceUpdated,
})
e.nsListerSynced = nsInformer.Informer().HasSynced
e.syncHandler = e.syncNamespace
return e, nil
}
// Publisher manages certificate ConfigMap objects inside Namespaces
type Publisher struct {
client clientset.Interface
rootCA []byte
// To allow injection for testing.
syncHandler func(ctx context.Context, key string) error
cmLister corelisters.ConfigMapLister
cmListerSynced cache.InformerSynced
nsListerSynced cache.InformerSynced
queue workqueue.RateLimitingInterface
}
// Run starts process
func (c *Publisher) Run(ctx context.Context, workers int) {
defer utilruntime.HandleCrash()
defer c.queue.ShutDown()
klog.Infof("Starting root CA certificate configmap publisher")
defer klog.Infof("Shutting down root CA certificate configmap publisher")
if !cache.WaitForNamedCacheSync("crt configmap", ctx.Done(), c.cmListerSynced) {
return
}
for i := 0; i < workers; i++ {
go wait.UntilWithContext(ctx, c.runWorker, time.Second)
}
<-ctx.Done()
}
func (c *Publisher) configMapDeleted(obj interface{}) {
cm, err := convertToCM(obj)
if err != nil {
utilruntime.HandleError(err)
return
}
if cm.Name != RootCACertConfigMapName {
return
}
c.queue.Add(cm.Namespace)
}
func (c *Publisher) configMapUpdated(_, newObj interface{}) {
cm, err := convertToCM(newObj)
if err != nil {
utilruntime.HandleError(err)
return
}
if cm.Name != RootCACertConfigMapName {
return
}
c.queue.Add(cm.Namespace)
}
func (c *Publisher) namespaceAdded(obj interface{}) {
namespace := obj.(*v1.Namespace)
c.queue.Add(namespace.Name)
}
func (c *Publisher) namespaceUpdated(oldObj interface{}, newObj interface{}) {
newNamespace := newObj.(*v1.Namespace)
if newNamespace.Status.Phase != v1.NamespaceActive {
return
}
c.queue.Add(newNamespace.Name)
}
func (c *Publisher) runWorker(ctx context.Context) {
for c.processNextWorkItem(ctx) {
}
}
// processNextWorkItem deals with one key off the queue. It returns false when
// it's time to quit.
func (c *Publisher) processNextWorkItem(ctx context.Context) bool {
key, quit := c.queue.Get()
if quit {
return false
}
defer c.queue.Done(key)
if err := c.syncHandler(ctx, key.(string)); err != nil {
utilruntime.HandleError(fmt.Errorf("syncing %q failed: %v", key, err))
c.queue.AddRateLimited(key)
return true
}
c.queue.Forget(key)
return true
}
func (c *Publisher) syncNamespace(ctx context.Context, ns string) (err error) {
startTime := time.Now()
defer func() {
recordMetrics(startTime, err)
klog.V(4).Infof("Finished syncing namespace %q (%v)", ns, time.Since(startTime))
}()
cm, err := c.cmLister.ConfigMaps(ns).Get(RootCACertConfigMapName)
switch {
case apierrors.IsNotFound(err):
_, err = c.client.CoreV1().ConfigMaps(ns).Create(ctx, &v1.ConfigMap{
ObjectMeta: metav1.ObjectMeta{
Name: RootCACertConfigMapName,
Annotations: map[string]string{DescriptionAnnotation: Description},
},
Data: map[string]string{
"ca.crt": string(c.rootCA),
},
}, metav1.CreateOptions{})
// don't retry a create if the namespace doesn't exist or is terminating
if apierrors.IsNotFound(err) || apierrors.HasStatusCause(err, v1.NamespaceTerminatingCause) {
return nil
}
return err
case err != nil:
return err
}
data := map[string]string{
"ca.crt": string(c.rootCA),
}
// ensure the data and the one annotation describing usage of this configmap match.
if reflect.DeepEqual(cm.Data, data) && len(cm.Annotations[DescriptionAnnotation]) > 0 {
return nil
}
// copy so we don't modify the cache's instance of the configmap
cm = cm.DeepCopy()
cm.Data = data
if cm.Annotations == nil {
cm.Annotations = map[string]string{}
}
cm.Annotations[DescriptionAnnotation] = Description
_, err = c.client.CoreV1().ConfigMaps(ns).Update(ctx, cm, metav1.UpdateOptions{})
return err
}
func convertToCM(obj interface{}) (*v1.ConfigMap, error) {
cm, ok := obj.(*v1.ConfigMap)
if !ok {
tombstone, ok := obj.(cache.DeletedFinalStateUnknown)
if !ok {
return nil, fmt.Errorf("couldn't get object from tombstone %#v", obj)
}
cm, ok = tombstone.Obj.(*v1.ConfigMap)
if !ok {
return nil, fmt.Errorf("tombstone contained object that is not a ConfigMap %#v", obj)
}
}
return cm, nil
}