-
Notifications
You must be signed in to change notification settings - Fork 39.2k
/
docker_sandbox.go
744 lines (649 loc) · 26.6 KB
/
docker_sandbox.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
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
/*
Copyright 2016 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 dockershim
import (
"context"
"encoding/json"
"fmt"
"os"
"strings"
"time"
dockertypes "github.com/docker/docker/api/types"
dockercontainer "github.com/docker/docker/api/types/container"
dockerfilters "github.com/docker/docker/api/types/filters"
utilerrors "k8s.io/apimachinery/pkg/util/errors"
"k8s.io/klog"
runtimeapi "k8s.io/kubernetes/pkg/kubelet/apis/cri/runtime/v1alpha2"
"k8s.io/kubernetes/pkg/kubelet/checkpointmanager"
"k8s.io/kubernetes/pkg/kubelet/checkpointmanager/errors"
kubecontainer "k8s.io/kubernetes/pkg/kubelet/container"
"k8s.io/kubernetes/pkg/kubelet/dockershim/libdocker"
"k8s.io/kubernetes/pkg/kubelet/qos"
"k8s.io/kubernetes/pkg/kubelet/types"
)
const (
defaultSandboxImage = "k8s.gcr.io/pause:3.1"
// Various default sandbox resources requests/limits.
defaultSandboxCPUshares int64 = 2
// Name of the underlying container runtime
runtimeName = "docker"
)
var (
// Termination grace period
defaultSandboxGracePeriod = time.Duration(10) * time.Second
)
// Returns whether the sandbox network is ready, and whether the sandbox is known
func (ds *dockerService) getNetworkReady(podSandboxID string) (bool, bool) {
ds.networkReadyLock.Lock()
defer ds.networkReadyLock.Unlock()
ready, ok := ds.networkReady[podSandboxID]
return ready, ok
}
func (ds *dockerService) setNetworkReady(podSandboxID string, ready bool) {
ds.networkReadyLock.Lock()
defer ds.networkReadyLock.Unlock()
ds.networkReady[podSandboxID] = ready
}
func (ds *dockerService) clearNetworkReady(podSandboxID string) {
ds.networkReadyLock.Lock()
defer ds.networkReadyLock.Unlock()
delete(ds.networkReady, podSandboxID)
}
// RunPodSandbox creates and starts a pod-level sandbox. Runtimes should ensure
// the sandbox is in ready state.
// For docker, PodSandbox is implemented by a container holding the network
// namespace for the pod.
// Note: docker doesn't use LogDirectory (yet).
func (ds *dockerService) RunPodSandbox(ctx context.Context, r *runtimeapi.RunPodSandboxRequest) (*runtimeapi.RunPodSandboxResponse, error) {
config := r.GetConfig()
// Step 1: Pull the image for the sandbox.
image := defaultSandboxImage
podSandboxImage := ds.podSandboxImage
if len(podSandboxImage) != 0 {
image = podSandboxImage
}
// NOTE: To use a custom sandbox image in a private repository, users need to configure the nodes with credentials properly.
// see: http://kubernetes.io/docs/user-guide/images/#configuring-nodes-to-authenticate-to-a-private-repository
// Only pull sandbox image when it's not present - v1.PullIfNotPresent.
if err := ensureSandboxImageExists(ds.client, image); err != nil {
return nil, err
}
// Step 2: Create the sandbox container.
if r.GetRuntimeHandler() != "" {
return nil, fmt.Errorf("RuntimeHandler %q not supported", r.GetRuntimeHandler())
}
createConfig, err := ds.makeSandboxDockerConfig(config, image)
if err != nil {
return nil, fmt.Errorf("failed to make sandbox docker config for pod %q: %v", config.Metadata.Name, err)
}
createResp, err := ds.client.CreateContainer(*createConfig)
if err != nil {
createResp, err = recoverFromCreationConflictIfNeeded(ds.client, *createConfig, err)
}
if err != nil || createResp == nil {
return nil, fmt.Errorf("failed to create a sandbox for pod %q: %v", config.Metadata.Name, err)
}
resp := &runtimeapi.RunPodSandboxResponse{PodSandboxId: createResp.ID}
ds.setNetworkReady(createResp.ID, false)
defer func(e *error) {
// Set networking ready depending on the error return of
// the parent function
if *e == nil {
ds.setNetworkReady(createResp.ID, true)
}
}(&err)
// Step 3: Create Sandbox Checkpoint.
if err = ds.checkpointManager.CreateCheckpoint(createResp.ID, constructPodSandboxCheckpoint(config)); err != nil {
return nil, err
}
// Step 4: Start the sandbox container.
// Assume kubelet's garbage collector would remove the sandbox later, if
// startContainer failed.
err = ds.client.StartContainer(createResp.ID)
if err != nil {
return nil, fmt.Errorf("failed to start sandbox container for pod %q: %v", config.Metadata.Name, err)
}
// Rewrite resolv.conf file generated by docker.
// NOTE: cluster dns settings aren't passed anymore to docker api in all cases,
// not only for pods with host network: the resolver conf will be overwritten
// after sandbox creation to override docker's behaviour. This resolv.conf
// file is shared by all containers of the same pod, and needs to be modified
// only once per pod.
if dnsConfig := config.GetDnsConfig(); dnsConfig != nil {
containerInfo, err := ds.client.InspectContainer(createResp.ID)
if err != nil {
return nil, fmt.Errorf("failed to inspect sandbox container for pod %q: %v", config.Metadata.Name, err)
}
if err := rewriteResolvFile(containerInfo.ResolvConfPath, dnsConfig.Servers, dnsConfig.Searches, dnsConfig.Options); err != nil {
return nil, fmt.Errorf("rewrite resolv.conf failed for pod %q: %v", config.Metadata.Name, err)
}
}
// Do not invoke network plugins if in hostNetwork mode.
if config.GetLinux().GetSecurityContext().GetNamespaceOptions().GetNetwork() == runtimeapi.NamespaceMode_NODE {
return resp, nil
}
// Step 5: Setup networking for the sandbox.
// All pod networking is setup by a CNI plugin discovered at startup time.
// This plugin assigns the pod ip, sets up routes inside the sandbox,
// creates interfaces etc. In theory, its jurisdiction ends with pod
// sandbox networking, but it might insert iptables rules or open ports
// on the host as well, to satisfy parts of the pod spec that aren't
// recognized by the CNI standard yet.
cID := kubecontainer.BuildContainerID(runtimeName, createResp.ID)
networkOptions := make(map[string]string)
if dnsConfig := config.GetDnsConfig(); dnsConfig != nil {
// Build DNS options.
dnsOption, err := json.Marshal(dnsConfig)
if err != nil {
return nil, fmt.Errorf("failed to marshal dns config for pod %q: %v", config.Metadata.Name, err)
}
networkOptions["dns"] = string(dnsOption)
}
err = ds.network.SetUpPod(config.GetMetadata().Namespace, config.GetMetadata().Name, cID, config.Annotations, networkOptions)
if err != nil {
errList := []error{fmt.Errorf("failed to set up sandbox container %q network for pod %q: %v", createResp.ID, config.Metadata.Name, err)}
// Ensure network resources are cleaned up even if the plugin
// succeeded but an error happened between that success and here.
err = ds.network.TearDownPod(config.GetMetadata().Namespace, config.GetMetadata().Name, cID)
if err != nil {
errList = append(errList, fmt.Errorf("failed to clean up sandbox container %q network for pod %q: %v", createResp.ID, config.Metadata.Name, err))
}
err = ds.client.StopContainer(createResp.ID, defaultSandboxGracePeriod)
if err != nil {
errList = append(errList, fmt.Errorf("failed to stop sandbox container %q for pod %q: %v", createResp.ID, config.Metadata.Name, err))
}
return resp, utilerrors.NewAggregate(errList)
}
return resp, nil
}
// StopPodSandbox stops the sandbox. If there are any running containers in the
// sandbox, they should be force terminated.
// TODO: This function blocks sandbox teardown on networking teardown. Is it
// better to cut our losses assuming an out of band GC routine will cleanup
// after us?
func (ds *dockerService) StopPodSandbox(ctx context.Context, r *runtimeapi.StopPodSandboxRequest) (*runtimeapi.StopPodSandboxResponse, error) {
var namespace, name string
var hostNetwork bool
podSandboxID := r.PodSandboxId
resp := &runtimeapi.StopPodSandboxResponse{}
// Try to retrieve minimal sandbox information from docker daemon or sandbox checkpoint.
inspectResult, metadata, statusErr := ds.getPodSandboxDetails(podSandboxID)
if statusErr == nil {
namespace = metadata.Namespace
name = metadata.Name
hostNetwork = (networkNamespaceMode(inspectResult) == runtimeapi.NamespaceMode_NODE)
} else {
checkpoint := NewPodSandboxCheckpoint("", "", &CheckpointData{})
checkpointErr := ds.checkpointManager.GetCheckpoint(podSandboxID, checkpoint)
// Proceed if both sandbox container and checkpoint could not be found. This means that following
// actions will only have sandbox ID and not have pod namespace and name information.
// Return error if encounter any unexpected error.
if checkpointErr != nil {
if checkpointErr != errors.ErrCheckpointNotFound {
err := ds.checkpointManager.RemoveCheckpoint(podSandboxID)
if err != nil {
klog.Errorf("Failed to delete corrupt checkpoint for sandbox %q: %v", podSandboxID, err)
}
}
if libdocker.IsContainerNotFoundError(statusErr) {
klog.Warningf("Both sandbox container and checkpoint for id %q could not be found. "+
"Proceed without further sandbox information.", podSandboxID)
} else {
return nil, utilerrors.NewAggregate([]error{
fmt.Errorf("failed to get checkpoint for sandbox %q: %v", podSandboxID, checkpointErr),
fmt.Errorf("failed to get sandbox status: %v", statusErr)})
}
} else {
_, name, namespace, _, hostNetwork = checkpoint.GetData()
}
}
// WARNING: The following operations made the following assumption:
// 1. kubelet will retry on any error returned by StopPodSandbox.
// 2. tearing down network and stopping sandbox container can succeed in any sequence.
// This depends on the implementation detail of network plugin and proper error handling.
// For kubenet, if tearing down network failed and sandbox container is stopped, kubelet
// will retry. On retry, kubenet will not be able to retrieve network namespace of the sandbox
// since it is stopped. With empty network namespcae, CNI bridge plugin will conduct best
// effort clean up and will not return error.
errList := []error{}
ready, ok := ds.getNetworkReady(podSandboxID)
if !hostNetwork && (ready || !ok) {
// Only tear down the pod network if we haven't done so already
cID := kubecontainer.BuildContainerID(runtimeName, podSandboxID)
err := ds.network.TearDownPod(namespace, name, cID)
if err == nil {
ds.setNetworkReady(podSandboxID, false)
} else {
errList = append(errList, err)
}
}
if err := ds.client.StopContainer(podSandboxID, defaultSandboxGracePeriod); err != nil {
// Do not return error if the container does not exist
if !libdocker.IsContainerNotFoundError(err) {
klog.Errorf("Failed to stop sandbox %q: %v", podSandboxID, err)
errList = append(errList, err)
} else {
// remove the checkpoint for any sandbox that is not found in the runtime
ds.checkpointManager.RemoveCheckpoint(podSandboxID)
}
}
if len(errList) == 0 {
return resp, nil
}
// TODO: Stop all running containers in the sandbox.
return nil, utilerrors.NewAggregate(errList)
}
// RemovePodSandbox removes the sandbox. If there are running containers in the
// sandbox, they should be forcibly removed.
func (ds *dockerService) RemovePodSandbox(ctx context.Context, r *runtimeapi.RemovePodSandboxRequest) (*runtimeapi.RemovePodSandboxResponse, error) {
podSandboxID := r.PodSandboxId
var errs []error
opts := dockertypes.ContainerListOptions{All: true}
opts.Filters = dockerfilters.NewArgs()
f := newDockerFilter(&opts.Filters)
f.AddLabel(sandboxIDLabelKey, podSandboxID)
containers, err := ds.client.ListContainers(opts)
if err != nil {
errs = append(errs, err)
}
// Remove all containers in the sandbox.
for i := range containers {
if _, err := ds.RemoveContainer(ctx, &runtimeapi.RemoveContainerRequest{ContainerId: containers[i].ID}); err != nil && !libdocker.IsContainerNotFoundError(err) {
errs = append(errs, err)
}
}
// Remove the sandbox container.
err = ds.client.RemoveContainer(podSandboxID, dockertypes.ContainerRemoveOptions{RemoveVolumes: true, Force: true})
if err == nil || libdocker.IsContainerNotFoundError(err) {
// Only clear network ready when the sandbox has actually been
// removed from docker or doesn't exist
ds.clearNetworkReady(podSandboxID)
} else {
errs = append(errs, err)
}
// Remove the checkpoint of the sandbox.
if err := ds.checkpointManager.RemoveCheckpoint(podSandboxID); err != nil {
errs = append(errs, err)
}
if len(errs) == 0 {
return &runtimeapi.RemovePodSandboxResponse{}, nil
}
return nil, utilerrors.NewAggregate(errs)
}
// getIPFromPlugin interrogates the network plugin for an IP.
func (ds *dockerService) getIPFromPlugin(sandbox *dockertypes.ContainerJSON) (string, error) {
metadata, err := parseSandboxName(sandbox.Name)
if err != nil {
return "", err
}
msg := fmt.Sprintf("Couldn't find network status for %s/%s through plugin", metadata.Namespace, metadata.Name)
cID := kubecontainer.BuildContainerID(runtimeName, sandbox.ID)
networkStatus, err := ds.network.GetPodNetworkStatus(metadata.Namespace, metadata.Name, cID)
if err != nil {
return "", err
}
if networkStatus == nil {
return "", fmt.Errorf("%v: invalid network status for", msg)
}
return networkStatus.IP.String(), nil
}
// getIP returns the ip given the output of `docker inspect` on a pod sandbox,
// first interrogating any registered plugins, then simply trusting the ip
// in the sandbox itself. We look for an ipv4 address before ipv6.
func (ds *dockerService) getIP(podSandboxID string, sandbox *dockertypes.ContainerJSON) string {
if sandbox.NetworkSettings == nil {
return ""
}
if networkNamespaceMode(sandbox) == runtimeapi.NamespaceMode_NODE {
// For sandboxes using host network, the shim is not responsible for
// reporting the IP.
return ""
}
// Don't bother getting IP if the pod is known and networking isn't ready
ready, ok := ds.getNetworkReady(podSandboxID)
if ok && !ready {
return ""
}
ip, err := ds.getIPFromPlugin(sandbox)
if err == nil {
return ip
}
// TODO: trusting the docker ip is not a great idea. However docker uses
// eth0 by default and so does CNI, so if we find a docker IP here, we
// conclude that the plugin must have failed setup, or forgotten its ip.
// This is not a sensible assumption for plugins across the board, but if
// a plugin doesn't want this behavior, it can throw an error.
if sandbox.NetworkSettings.IPAddress != "" {
return sandbox.NetworkSettings.IPAddress
}
if sandbox.NetworkSettings.GlobalIPv6Address != "" {
return sandbox.NetworkSettings.GlobalIPv6Address
}
// If all else fails, warn but don't return an error, as pod status
// should generally not return anything except fatal errors
// FIXME: handle network errors by restarting the pod somehow?
klog.Warningf("failed to read pod IP from plugin/docker: %v", err)
return ""
}
// Returns the inspect container response, the sandbox metadata, and network namespace mode
func (ds *dockerService) getPodSandboxDetails(podSandboxID string) (*dockertypes.ContainerJSON, *runtimeapi.PodSandboxMetadata, error) {
resp, err := ds.client.InspectContainer(podSandboxID)
if err != nil {
return nil, nil, err
}
metadata, err := parseSandboxName(resp.Name)
if err != nil {
return nil, nil, err
}
return resp, metadata, nil
}
// PodSandboxStatus returns the status of the PodSandbox.
func (ds *dockerService) PodSandboxStatus(ctx context.Context, req *runtimeapi.PodSandboxStatusRequest) (*runtimeapi.PodSandboxStatusResponse, error) {
podSandboxID := req.PodSandboxId
r, metadata, err := ds.getPodSandboxDetails(podSandboxID)
if err != nil {
return nil, err
}
// Parse the timestamps.
createdAt, _, _, err := getContainerTimestamps(r)
if err != nil {
return nil, fmt.Errorf("failed to parse timestamp for container %q: %v", podSandboxID, err)
}
ct := createdAt.UnixNano()
// Translate container to sandbox state.
state := runtimeapi.PodSandboxState_SANDBOX_NOTREADY
if r.State.Running {
state = runtimeapi.PodSandboxState_SANDBOX_READY
}
var IP string
// TODO: Remove this when sandbox is available on windows
// This is a workaround for windows, where sandbox is not in use, and pod IP is determined through containers belonging to the Pod.
if IP = ds.determinePodIPBySandboxID(podSandboxID); IP == "" {
IP = ds.getIP(podSandboxID, r)
}
labels, annotations := extractLabels(r.Config.Labels)
status := &runtimeapi.PodSandboxStatus{
Id: r.ID,
State: state,
CreatedAt: ct,
Metadata: metadata,
Labels: labels,
Annotations: annotations,
Network: &runtimeapi.PodSandboxNetworkStatus{
Ip: IP,
},
Linux: &runtimeapi.LinuxPodSandboxStatus{
Namespaces: &runtimeapi.Namespace{
Options: &runtimeapi.NamespaceOption{
Network: networkNamespaceMode(r),
Pid: pidNamespaceMode(r),
Ipc: ipcNamespaceMode(r),
},
},
},
}
return &runtimeapi.PodSandboxStatusResponse{Status: status}, nil
}
// ListPodSandbox returns a list of Sandbox.
func (ds *dockerService) ListPodSandbox(_ context.Context, r *runtimeapi.ListPodSandboxRequest) (*runtimeapi.ListPodSandboxResponse, error) {
filter := r.GetFilter()
// By default, list all containers whether they are running or not.
opts := dockertypes.ContainerListOptions{All: true}
filterOutReadySandboxes := false
opts.Filters = dockerfilters.NewArgs()
f := newDockerFilter(&opts.Filters)
// Add filter to select only sandbox containers.
f.AddLabel(containerTypeLabelKey, containerTypeLabelSandbox)
if filter != nil {
if filter.Id != "" {
f.Add("id", filter.Id)
}
if filter.State != nil {
if filter.GetState().State == runtimeapi.PodSandboxState_SANDBOX_READY {
// Only list running containers.
opts.All = false
} else {
// runtimeapi.PodSandboxState_SANDBOX_NOTREADY can mean the
// container is in any of the non-running state (e.g., created,
// exited). We can't tell docker to filter out running
// containers directly, so we'll need to filter them out
// ourselves after getting the results.
filterOutReadySandboxes = true
}
}
if filter.LabelSelector != nil {
for k, v := range filter.LabelSelector {
f.AddLabel(k, v)
}
}
}
// Make sure we get the list of checkpoints first so that we don't include
// new PodSandboxes that are being created right now.
var err error
checkpoints := []string{}
if filter == nil {
checkpoints, err = ds.checkpointManager.ListCheckpoints()
if err != nil {
klog.Errorf("Failed to list checkpoints: %v", err)
}
}
containers, err := ds.client.ListContainers(opts)
if err != nil {
return nil, err
}
// Convert docker containers to runtime api sandboxes.
result := []*runtimeapi.PodSandbox{}
// using map as set
sandboxIDs := make(map[string]bool)
for i := range containers {
c := containers[i]
converted, err := containerToRuntimeAPISandbox(&c)
if err != nil {
klog.V(4).Infof("Unable to convert docker to runtime API sandbox %+v: %v", c, err)
continue
}
if filterOutReadySandboxes && converted.State == runtimeapi.PodSandboxState_SANDBOX_READY {
continue
}
sandboxIDs[converted.Id] = true
result = append(result, converted)
}
// Include sandbox that could only be found with its checkpoint if no filter is applied
// These PodSandbox will only include PodSandboxID, Name, Namespace.
// These PodSandbox will be in PodSandboxState_SANDBOX_NOTREADY state.
for _, id := range checkpoints {
if _, ok := sandboxIDs[id]; ok {
continue
}
checkpoint := NewPodSandboxCheckpoint("", "", &CheckpointData{})
err := ds.checkpointManager.GetCheckpoint(id, checkpoint)
if err != nil {
klog.Errorf("Failed to retrieve checkpoint for sandbox %q: %v", id, err)
if err == errors.ErrCorruptCheckpoint {
err = ds.checkpointManager.RemoveCheckpoint(id)
if err != nil {
klog.Errorf("Failed to delete corrupt checkpoint for sandbox %q: %v", id, err)
}
}
continue
}
result = append(result, checkpointToRuntimeAPISandbox(id, checkpoint))
}
return &runtimeapi.ListPodSandboxResponse{Items: result}, nil
}
// applySandboxLinuxOptions applies LinuxPodSandboxConfig to dockercontainer.HostConfig and dockercontainer.ContainerCreateConfig.
func (ds *dockerService) applySandboxLinuxOptions(hc *dockercontainer.HostConfig, lc *runtimeapi.LinuxPodSandboxConfig, createConfig *dockertypes.ContainerCreateConfig, image string, separator rune) error {
if lc == nil {
return nil
}
// Apply security context.
if err := applySandboxSecurityContext(lc, createConfig.Config, hc, ds.network, separator); err != nil {
return err
}
// Set sysctls.
hc.Sysctls = lc.Sysctls
return nil
}
func (ds *dockerService) applySandboxResources(hc *dockercontainer.HostConfig, lc *runtimeapi.LinuxPodSandboxConfig) error {
hc.Resources = dockercontainer.Resources{
MemorySwap: DefaultMemorySwap(),
CPUShares: defaultSandboxCPUshares,
// Use docker's default cpu quota/period.
}
if lc != nil {
// Apply Cgroup options.
cgroupParent, err := ds.GenerateExpectedCgroupParent(lc.CgroupParent)
if err != nil {
return err
}
hc.CgroupParent = cgroupParent
}
return nil
}
// makeSandboxDockerConfig returns dockertypes.ContainerCreateConfig based on runtimeapi.PodSandboxConfig.
func (ds *dockerService) makeSandboxDockerConfig(c *runtimeapi.PodSandboxConfig, image string) (*dockertypes.ContainerCreateConfig, error) {
// Merge annotations and labels because docker supports only labels.
labels := makeLabels(c.GetLabels(), c.GetAnnotations())
// Apply a label to distinguish sandboxes from regular containers.
labels[containerTypeLabelKey] = containerTypeLabelSandbox
// Apply a container name label for infra container. This is used in summary v1.
// TODO(random-liu): Deprecate this label once container metrics is directly got from CRI.
labels[types.KubernetesContainerNameLabel] = sandboxContainerName
hc := &dockercontainer.HostConfig{
IpcMode: dockercontainer.IpcMode("shareable"),
}
createConfig := &dockertypes.ContainerCreateConfig{
Name: makeSandboxName(c),
Config: &dockercontainer.Config{
Hostname: c.Hostname,
// TODO: Handle environment variables.
Image: image,
Labels: labels,
},
HostConfig: hc,
}
// Apply linux-specific options.
if err := ds.applySandboxLinuxOptions(hc, c.GetLinux(), createConfig, image, securityOptSeparator); err != nil {
return nil, err
}
// Set port mappings.
exposedPorts, portBindings := makePortsAndBindings(c.GetPortMappings())
createConfig.Config.ExposedPorts = exposedPorts
hc.PortBindings = portBindings
// TODO: Get rid of the dependency on kubelet internal package.
hc.OomScoreAdj = qos.PodInfraOOMAdj
// Apply resource options.
if err := ds.applySandboxResources(hc, c.GetLinux()); err != nil {
return nil, err
}
// Set security options.
securityOpts, err := ds.getSecurityOpts(c.GetLinux().GetSecurityContext().GetSeccompProfilePath(), securityOptSeparator)
if err != nil {
return nil, fmt.Errorf("failed to generate sandbox security options for sandbox %q: %v", c.Metadata.Name, err)
}
hc.SecurityOpt = append(hc.SecurityOpt, securityOpts...)
applyExperimentalCreateConfig(createConfig, c.Annotations)
return createConfig, nil
}
// networkNamespaceMode returns the network runtimeapi.NamespaceMode for this container.
// Supports: POD, NODE
func networkNamespaceMode(container *dockertypes.ContainerJSON) runtimeapi.NamespaceMode {
if container != nil && container.HostConfig != nil && string(container.HostConfig.NetworkMode) == namespaceModeHost {
return runtimeapi.NamespaceMode_NODE
}
return runtimeapi.NamespaceMode_POD
}
// pidNamespaceMode returns the PID runtimeapi.NamespaceMode for this container.
// Supports: CONTAINER, NODE
// TODO(verb): add support for POD PID namespace sharing
func pidNamespaceMode(container *dockertypes.ContainerJSON) runtimeapi.NamespaceMode {
if container != nil && container.HostConfig != nil && string(container.HostConfig.PidMode) == namespaceModeHost {
return runtimeapi.NamespaceMode_NODE
}
return runtimeapi.NamespaceMode_CONTAINER
}
// ipcNamespaceMode returns the IPC runtimeapi.NamespaceMode for this container.
// Supports: POD, NODE
func ipcNamespaceMode(container *dockertypes.ContainerJSON) runtimeapi.NamespaceMode {
if container != nil && container.HostConfig != nil && string(container.HostConfig.IpcMode) == namespaceModeHost {
return runtimeapi.NamespaceMode_NODE
}
return runtimeapi.NamespaceMode_POD
}
func constructPodSandboxCheckpoint(config *runtimeapi.PodSandboxConfig) checkpointmanager.Checkpoint {
data := CheckpointData{}
for _, pm := range config.GetPortMappings() {
proto := toCheckpointProtocol(pm.Protocol)
data.PortMappings = append(data.PortMappings, &PortMapping{
HostPort: &pm.HostPort,
ContainerPort: &pm.ContainerPort,
Protocol: &proto,
HostIP: pm.HostIp,
})
}
if config.GetLinux().GetSecurityContext().GetNamespaceOptions().GetNetwork() == runtimeapi.NamespaceMode_NODE {
data.HostNetwork = true
}
return NewPodSandboxCheckpoint(config.Metadata.Namespace, config.Metadata.Name, &data)
}
func toCheckpointProtocol(protocol runtimeapi.Protocol) Protocol {
switch protocol {
case runtimeapi.Protocol_TCP:
return protocolTCP
case runtimeapi.Protocol_UDP:
return protocolUDP
case runtimeapi.Protocol_SCTP:
return protocolSCTP
}
klog.Warningf("Unknown protocol %q: defaulting to TCP", protocol)
return protocolTCP
}
// rewriteResolvFile rewrites resolv.conf file generated by docker.
func rewriteResolvFile(resolvFilePath string, dns []string, dnsSearch []string, dnsOptions []string) error {
if len(resolvFilePath) == 0 {
klog.Errorf("ResolvConfPath is empty.")
return nil
}
if _, err := os.Stat(resolvFilePath); os.IsNotExist(err) {
return fmt.Errorf("ResolvConfPath %q does not exist", resolvFilePath)
}
var resolvFileContent []string
for _, srv := range dns {
resolvFileContent = append(resolvFileContent, "nameserver "+srv)
}
if len(dnsSearch) > 0 {
resolvFileContent = append(resolvFileContent, "search "+strings.Join(dnsSearch, " "))
}
if len(dnsOptions) > 0 {
resolvFileContent = append(resolvFileContent, "options "+strings.Join(dnsOptions, " "))
}
if len(resolvFileContent) > 0 {
resolvFileContentStr := strings.Join(resolvFileContent, "\n")
resolvFileContentStr += "\n"
klog.V(4).Infof("Will attempt to re-write config file %s with: \n%s", resolvFilePath, resolvFileContent)
if err := rewriteFile(resolvFilePath, resolvFileContentStr); err != nil {
klog.Errorf("resolv.conf could not be updated: %v", err)
return err
}
}
return nil
}
func rewriteFile(filePath, stringToWrite string) error {
f, err := os.OpenFile(filePath, os.O_TRUNC|os.O_WRONLY, 0644)
if err != nil {
return err
}
defer f.Close()
_, err = f.WriteString(stringToWrite)
return err
}