forked from kubernetes/kubernetes
-
-
Notifications
You must be signed in to change notification settings - Fork 0
/
validation.go
444 lines (379 loc) · 18.8 KB
/
validation.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
/*
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 validation
import (
"fmt"
"path/filepath"
"reflect"
"regexp"
"strings"
apimachineryvalidation "k8s.io/apimachinery/pkg/api/validation"
unversionedvalidation "k8s.io/apimachinery/pkg/apis/meta/v1/validation"
"k8s.io/apimachinery/pkg/util/sets"
"k8s.io/apimachinery/pkg/util/validation/field"
core "k8s.io/kubernetes/pkg/apis/core"
apivalidation "k8s.io/kubernetes/pkg/apis/core/validation"
extensionsvalidation "k8s.io/kubernetes/pkg/apis/extensions/validation"
"k8s.io/kubernetes/pkg/apis/policy"
"k8s.io/kubernetes/pkg/features"
"k8s.io/kubernetes/pkg/security/apparmor"
"k8s.io/kubernetes/pkg/security/podsecuritypolicy/seccomp"
psputil "k8s.io/kubernetes/pkg/security/podsecuritypolicy/util"
utilfeature "k8s.io/apiserver/pkg/util/feature"
)
func ValidatePodDisruptionBudget(pdb *policy.PodDisruptionBudget) field.ErrorList {
allErrs := ValidatePodDisruptionBudgetSpec(pdb.Spec, field.NewPath("spec"))
allErrs = append(allErrs, ValidatePodDisruptionBudgetStatus(pdb.Status, field.NewPath("status"))...)
return allErrs
}
func ValidatePodDisruptionBudgetUpdate(pdb, oldPdb *policy.PodDisruptionBudget) field.ErrorList {
allErrs := field.ErrorList{}
restoreGeneration := pdb.Generation
pdb.Generation = oldPdb.Generation
if !reflect.DeepEqual(pdb.Spec, oldPdb.Spec) {
allErrs = append(allErrs, field.Forbidden(field.NewPath("spec"), "updates to poddisruptionbudget spec are forbidden."))
}
allErrs = append(allErrs, ValidatePodDisruptionBudgetStatus(pdb.Status, field.NewPath("status"))...)
pdb.Generation = restoreGeneration
return allErrs
}
func ValidatePodDisruptionBudgetSpec(spec policy.PodDisruptionBudgetSpec, fldPath *field.Path) field.ErrorList {
allErrs := field.ErrorList{}
if spec.MinAvailable != nil && spec.MaxUnavailable != nil {
allErrs = append(allErrs, field.Invalid(fldPath, spec, "minAvailable and maxUnavailable cannot be both set"))
}
if spec.MinAvailable != nil {
allErrs = append(allErrs, extensionsvalidation.ValidatePositiveIntOrPercent(*spec.MinAvailable, fldPath.Child("minAvailable"))...)
allErrs = append(allErrs, extensionsvalidation.IsNotMoreThan100Percent(*spec.MinAvailable, fldPath.Child("minAvailable"))...)
}
if spec.MaxUnavailable != nil {
allErrs = append(allErrs, extensionsvalidation.ValidatePositiveIntOrPercent(*spec.MaxUnavailable, fldPath.Child("maxUnavailable"))...)
allErrs = append(allErrs, extensionsvalidation.IsNotMoreThan100Percent(*spec.MaxUnavailable, fldPath.Child("maxUnavailable"))...)
}
allErrs = append(allErrs, unversionedvalidation.ValidateLabelSelector(spec.Selector, fldPath.Child("selector"))...)
return allErrs
}
func ValidatePodDisruptionBudgetStatus(status policy.PodDisruptionBudgetStatus, fldPath *field.Path) field.ErrorList {
allErrs := field.ErrorList{}
allErrs = append(allErrs, apivalidation.ValidateNonnegativeField(int64(status.PodDisruptionsAllowed), fldPath.Child("podDisruptionsAllowed"))...)
allErrs = append(allErrs, apivalidation.ValidateNonnegativeField(int64(status.CurrentHealthy), fldPath.Child("currentHealthy"))...)
allErrs = append(allErrs, apivalidation.ValidateNonnegativeField(int64(status.DesiredHealthy), fldPath.Child("desiredHealthy"))...)
allErrs = append(allErrs, apivalidation.ValidateNonnegativeField(int64(status.ExpectedPods), fldPath.Child("expectedPods"))...)
return allErrs
}
// ValidatePodSecurityPolicyName can be used to check whether the given
// pod security policy name is valid.
// Prefix indicates this name will be used as part of generation, in which case
// trailing dashes are allowed.
var ValidatePodSecurityPolicyName = apimachineryvalidation.NameIsDNSSubdomain
func ValidatePodSecurityPolicy(psp *policy.PodSecurityPolicy) field.ErrorList {
allErrs := field.ErrorList{}
allErrs = append(allErrs, apivalidation.ValidateObjectMeta(&psp.ObjectMeta, false, ValidatePodSecurityPolicyName, field.NewPath("metadata"))...)
allErrs = append(allErrs, ValidatePodSecurityPolicySpecificAnnotations(psp.Annotations, field.NewPath("metadata").Child("annotations"))...)
allErrs = append(allErrs, ValidatePodSecurityPolicySpec(&psp.Spec, field.NewPath("spec"))...)
return allErrs
}
func ValidatePodSecurityPolicySpec(spec *policy.PodSecurityPolicySpec, fldPath *field.Path) field.ErrorList {
allErrs := field.ErrorList{}
allErrs = append(allErrs, validatePSPRunAsUser(fldPath.Child("runAsUser"), &spec.RunAsUser)...)
allErrs = append(allErrs, validatePSPSELinux(fldPath.Child("seLinux"), &spec.SELinux)...)
allErrs = append(allErrs, validatePSPSupplementalGroup(fldPath.Child("supplementalGroups"), &spec.SupplementalGroups)...)
allErrs = append(allErrs, validatePSPFSGroup(fldPath.Child("fsGroup"), &spec.FSGroup)...)
allErrs = append(allErrs, validatePodSecurityPolicyVolumes(fldPath, spec.Volumes)...)
if len(spec.RequiredDropCapabilities) > 0 && hasCap(policy.AllowAllCapabilities, spec.AllowedCapabilities) {
allErrs = append(allErrs, field.Invalid(field.NewPath("requiredDropCapabilities"), spec.RequiredDropCapabilities,
"must be empty when all capabilities are allowed by a wildcard"))
}
allErrs = append(allErrs, validatePSPCapsAgainstDrops(spec.RequiredDropCapabilities, spec.DefaultAddCapabilities, field.NewPath("defaultAddCapabilities"))...)
allErrs = append(allErrs, validatePSPCapsAgainstDrops(spec.RequiredDropCapabilities, spec.AllowedCapabilities, field.NewPath("allowedCapabilities"))...)
allErrs = append(allErrs, validatePSPDefaultAllowPrivilegeEscalation(fldPath.Child("defaultAllowPrivilegeEscalation"), spec.DefaultAllowPrivilegeEscalation, spec.AllowPrivilegeEscalation)...)
allErrs = append(allErrs, validatePSPAllowedHostPaths(fldPath.Child("allowedHostPaths"), spec.AllowedHostPaths)...)
allErrs = append(allErrs, validatePSPAllowedFlexVolumes(fldPath.Child("allowedFlexVolumes"), spec.AllowedFlexVolumes)...)
allErrs = append(allErrs, validatePodSecurityPolicySysctls(fldPath.Child("allowedUnsafeSysctls"), spec.AllowedUnsafeSysctls)...)
allErrs = append(allErrs, validatePodSecurityPolicySysctls(fldPath.Child("forbiddenSysctls"), spec.ForbiddenSysctls)...)
allErrs = append(allErrs, validatePodSecurityPolicySysctlListsDoNotOverlap(fldPath.Child("allowedUnsafeSysctls"), fldPath.Child("forbiddenSysctls"), spec.AllowedUnsafeSysctls, spec.ForbiddenSysctls)...)
return allErrs
}
func ValidatePodSecurityPolicySpecificAnnotations(annotations map[string]string, fldPath *field.Path) field.ErrorList {
allErrs := field.ErrorList{}
if p := annotations[apparmor.DefaultProfileAnnotationKey]; p != "" {
if err := apparmor.ValidateProfileFormat(p); err != nil {
allErrs = append(allErrs, field.Invalid(fldPath.Key(apparmor.DefaultProfileAnnotationKey), p, err.Error()))
}
}
if allowed := annotations[apparmor.AllowedProfilesAnnotationKey]; allowed != "" {
for _, p := range strings.Split(allowed, ",") {
if err := apparmor.ValidateProfileFormat(p); err != nil {
allErrs = append(allErrs, field.Invalid(fldPath.Key(apparmor.AllowedProfilesAnnotationKey), allowed, err.Error()))
}
}
}
if p := annotations[seccomp.DefaultProfileAnnotationKey]; p != "" {
allErrs = append(allErrs, apivalidation.ValidateSeccompProfile(p, fldPath.Key(seccomp.DefaultProfileAnnotationKey))...)
}
if allowed := annotations[seccomp.AllowedProfilesAnnotationKey]; allowed != "" {
for _, p := range strings.Split(allowed, ",") {
if p == seccomp.AllowAny {
continue
}
allErrs = append(allErrs, apivalidation.ValidateSeccompProfile(p, fldPath.Key(seccomp.AllowedProfilesAnnotationKey))...)
}
}
return allErrs
}
// validatePSPAllowedHostPaths makes sure all allowed host paths follow:
// 1. path prefix is required
// 2. path prefix does not have any element which is ".."
func validatePSPAllowedHostPaths(fldPath *field.Path, allowedHostPaths []policy.AllowedHostPath) field.ErrorList {
allErrs := field.ErrorList{}
for i, target := range allowedHostPaths {
if target.PathPrefix == "" {
allErrs = append(allErrs, field.Required(fldPath.Index(i), "is required"))
break
}
parts := strings.Split(filepath.ToSlash(target.PathPrefix), "/")
for _, item := range parts {
if item == ".." {
allErrs = append(allErrs, field.Invalid(fldPath.Index(i), target.PathPrefix, "must not contain '..'"))
break // even for `../../..`, one error is sufficient to make the point
}
}
}
return allErrs
}
func validatePSPAllowedFlexVolumes(fldPath *field.Path, flexVolumes []policy.AllowedFlexVolume) field.ErrorList {
allErrs := field.ErrorList{}
if len(flexVolumes) > 0 {
for idx, fv := range flexVolumes {
if len(fv.Driver) == 0 {
allErrs = append(allErrs, field.Required(fldPath.Child("allowedFlexVolumes").Index(idx).Child("driver"),
"must specify a driver"))
}
}
}
return allErrs
}
// validatePSPSELinux validates the SELinux fields of PodSecurityPolicy.
func validatePSPSELinux(fldPath *field.Path, seLinux *policy.SELinuxStrategyOptions) field.ErrorList {
allErrs := field.ErrorList{}
// ensure the selinux strategy has a valid rule
supportedSELinuxRules := sets.NewString(
string(policy.SELinuxStrategyMustRunAs),
string(policy.SELinuxStrategyRunAsAny),
)
if !supportedSELinuxRules.Has(string(seLinux.Rule)) {
allErrs = append(allErrs, field.NotSupported(fldPath.Child("rule"), seLinux.Rule, supportedSELinuxRules.List()))
}
return allErrs
}
// validatePSPRunAsUser validates the RunAsUser fields of PodSecurityPolicy.
func validatePSPRunAsUser(fldPath *field.Path, runAsUser *policy.RunAsUserStrategyOptions) field.ErrorList {
allErrs := field.ErrorList{}
// ensure the user strategy has a valid rule
supportedRunAsUserRules := sets.NewString(
string(policy.RunAsUserStrategyMustRunAs),
string(policy.RunAsUserStrategyMustRunAsNonRoot),
string(policy.RunAsUserStrategyRunAsAny),
)
if !supportedRunAsUserRules.Has(string(runAsUser.Rule)) {
allErrs = append(allErrs, field.NotSupported(fldPath.Child("rule"), runAsUser.Rule, supportedRunAsUserRules.List()))
}
// validate range settings
for idx, rng := range runAsUser.Ranges {
allErrs = append(allErrs, validateUserIDRange(fldPath.Child("ranges").Index(idx), rng)...)
}
return allErrs
}
// validatePSPFSGroup validates the FSGroupStrategyOptions fields of the PodSecurityPolicy.
func validatePSPFSGroup(fldPath *field.Path, groupOptions *policy.FSGroupStrategyOptions) field.ErrorList {
allErrs := field.ErrorList{}
supportedRules := sets.NewString(
string(policy.FSGroupStrategyMustRunAs),
string(policy.FSGroupStrategyRunAsAny),
)
if !supportedRules.Has(string(groupOptions.Rule)) {
allErrs = append(allErrs, field.NotSupported(fldPath.Child("rule"), groupOptions.Rule, supportedRules.List()))
}
for idx, rng := range groupOptions.Ranges {
allErrs = append(allErrs, validateGroupIDRange(fldPath.Child("ranges").Index(idx), rng)...)
}
return allErrs
}
// validatePSPSupplementalGroup validates the SupplementalGroupsStrategyOptions fields of the PodSecurityPolicy.
func validatePSPSupplementalGroup(fldPath *field.Path, groupOptions *policy.SupplementalGroupsStrategyOptions) field.ErrorList {
allErrs := field.ErrorList{}
supportedRules := sets.NewString(
string(policy.SupplementalGroupsStrategyRunAsAny),
string(policy.SupplementalGroupsStrategyMustRunAs),
)
if !supportedRules.Has(string(groupOptions.Rule)) {
allErrs = append(allErrs, field.NotSupported(fldPath.Child("rule"), groupOptions.Rule, supportedRules.List()))
}
for idx, rng := range groupOptions.Ranges {
allErrs = append(allErrs, validateGroupIDRange(fldPath.Child("ranges").Index(idx), rng)...)
}
return allErrs
}
// validatePodSecurityPolicyVolumes validates the volume fields of PodSecurityPolicy.
func validatePodSecurityPolicyVolumes(fldPath *field.Path, volumes []policy.FSType) field.ErrorList {
allErrs := field.ErrorList{}
allowed := psputil.GetAllFSTypesAsSet()
// add in the * value since that is a pseudo type that is not included by default
allowed.Insert(string(policy.All))
for _, v := range volumes {
if !allowed.Has(string(v)) {
allErrs = append(allErrs, field.NotSupported(fldPath.Child("volumes"), v, allowed.List()))
}
}
return allErrs
}
// validatePSPDefaultAllowPrivilegeEscalation validates the DefaultAllowPrivilegeEscalation field against the AllowPrivilegeEscalation field of a PodSecurityPolicy.
func validatePSPDefaultAllowPrivilegeEscalation(fldPath *field.Path, defaultAllowPrivilegeEscalation *bool, allowPrivilegeEscalation bool) field.ErrorList {
allErrs := field.ErrorList{}
if defaultAllowPrivilegeEscalation != nil && *defaultAllowPrivilegeEscalation && !allowPrivilegeEscalation {
allErrs = append(allErrs, field.Invalid(fldPath, defaultAllowPrivilegeEscalation, "Cannot set DefaultAllowPrivilegeEscalation to true without also setting AllowPrivilegeEscalation to true"))
}
return allErrs
}
const sysctlPatternSegmentFmt string = "([a-z0-9][-_a-z0-9]*)?[a-z0-9*]"
const SysctlPatternFmt string = "(" + apivalidation.SysctlSegmentFmt + "\\.)*" + sysctlPatternSegmentFmt
var sysctlPatternRegexp = regexp.MustCompile("^" + SysctlPatternFmt + "$")
func IsValidSysctlPattern(name string) bool {
if len(name) > apivalidation.SysctlMaxLength {
return false
}
return sysctlPatternRegexp.MatchString(name)
}
func validatePodSecurityPolicySysctlListsDoNotOverlap(allowedSysctlsFldPath, forbiddenSysctlsFldPath *field.Path, allowedUnsafeSysctls, forbiddenSysctls []string) field.ErrorList {
allErrs := field.ErrorList{}
for i, allowedSysctl := range allowedUnsafeSysctls {
isAllowedSysctlPattern := false
allowedSysctlPrefix := ""
if strings.HasSuffix(allowedSysctl, "*") {
isAllowedSysctlPattern = true
allowedSysctlPrefix = strings.TrimSuffix(allowedSysctl, "*")
}
for j, forbiddenSysctl := range forbiddenSysctls {
isForbiddenSysctlPattern := false
forbiddenSysctlPrefix := ""
if strings.HasSuffix(forbiddenSysctl, "*") {
isForbiddenSysctlPattern = true
forbiddenSysctlPrefix = strings.TrimSuffix(forbiddenSysctl, "*")
}
switch {
case isAllowedSysctlPattern && isForbiddenSysctlPattern:
if strings.HasPrefix(allowedSysctlPrefix, forbiddenSysctlPrefix) {
allErrs = append(allErrs, field.Invalid(allowedSysctlsFldPath.Index(i), allowedUnsafeSysctls[i], fmt.Sprintf("sysctl overlaps with %v", forbiddenSysctl)))
} else if strings.HasPrefix(forbiddenSysctlPrefix, allowedSysctlPrefix) {
allErrs = append(allErrs, field.Invalid(forbiddenSysctlsFldPath.Index(j), forbiddenSysctls[j], fmt.Sprintf("sysctl overlaps with %v", allowedSysctl)))
}
case isAllowedSysctlPattern:
if strings.HasPrefix(forbiddenSysctl, allowedSysctlPrefix) {
allErrs = append(allErrs, field.Invalid(forbiddenSysctlsFldPath.Index(j), forbiddenSysctls[j], fmt.Sprintf("sysctl overlaps with %v", allowedSysctl)))
}
case isForbiddenSysctlPattern:
if strings.HasPrefix(allowedSysctl, forbiddenSysctlPrefix) {
allErrs = append(allErrs, field.Invalid(allowedSysctlsFldPath.Index(i), allowedUnsafeSysctls[i], fmt.Sprintf("sysctl overlaps with %v", forbiddenSysctl)))
}
default:
if allowedSysctl == forbiddenSysctl {
allErrs = append(allErrs, field.Invalid(allowedSysctlsFldPath.Index(i), allowedUnsafeSysctls[i], fmt.Sprintf("sysctl overlaps with %v", forbiddenSysctl)))
}
}
}
}
return allErrs
}
// validatePodSecurityPolicySysctls validates the sysctls fields of PodSecurityPolicy.
func validatePodSecurityPolicySysctls(fldPath *field.Path, sysctls []string) field.ErrorList {
allErrs := field.ErrorList{}
if len(sysctls) == 0 {
return allErrs
}
if !utilfeature.DefaultFeatureGate.Enabled(features.Sysctls) {
return append(allErrs, field.Forbidden(fldPath, "Sysctls are disabled by Sysctls feature-gate"))
}
coversAll := false
for i, s := range sysctls {
if len(s) == 0 {
allErrs = append(allErrs, field.Invalid(fldPath.Index(i), sysctls[i], fmt.Sprintf("empty sysctl not allowed")))
} else if !IsValidSysctlPattern(string(s)) {
allErrs = append(
allErrs,
field.Invalid(fldPath.Index(i), sysctls[i], fmt.Sprintf("must have at most %d characters and match regex %s",
apivalidation.SysctlMaxLength,
SysctlPatternFmt,
)),
)
} else if s[0] == '*' {
coversAll = true
}
}
if coversAll && len(sysctls) > 1 {
allErrs = append(allErrs, field.Forbidden(fldPath.Child("items"), fmt.Sprintf("if '*' is present, must not specify other sysctls")))
}
return allErrs
}
func validateUserIDRange(fldPath *field.Path, rng policy.IDRange) field.ErrorList {
return validateIDRanges(fldPath, rng.Min, rng.Max)
}
func validateGroupIDRange(fldPath *field.Path, rng policy.IDRange) field.ErrorList {
return validateIDRanges(fldPath, rng.Min, rng.Max)
}
// validateIDRanges ensures the range is valid.
func validateIDRanges(fldPath *field.Path, min, max int64) field.ErrorList {
allErrs := field.ErrorList{}
// if 0 <= Min <= Max then we do not need to validate max. It is always greater than or
// equal to 0 and Min.
if min < 0 {
allErrs = append(allErrs, field.Invalid(fldPath.Child("min"), min, "min cannot be negative"))
}
if max < 0 {
allErrs = append(allErrs, field.Invalid(fldPath.Child("max"), max, "max cannot be negative"))
}
if min > max {
allErrs = append(allErrs, field.Invalid(fldPath.Child("min"), min, "min cannot be greater than max"))
}
return allErrs
}
// validatePSPCapsAgainstDrops ensures an allowed cap is not listed in the required drops.
func validatePSPCapsAgainstDrops(requiredDrops []core.Capability, capsToCheck []core.Capability, fldPath *field.Path) field.ErrorList {
allErrs := field.ErrorList{}
if requiredDrops == nil {
return allErrs
}
for _, cap := range capsToCheck {
if hasCap(cap, requiredDrops) {
allErrs = append(allErrs, field.Invalid(fldPath, cap,
fmt.Sprintf("capability is listed in %s and requiredDropCapabilities", fldPath.String())))
}
}
return allErrs
}
// ValidatePodSecurityPolicyUpdate validates a PSP for updates.
func ValidatePodSecurityPolicyUpdate(old *policy.PodSecurityPolicy, new *policy.PodSecurityPolicy) field.ErrorList {
allErrs := field.ErrorList{}
allErrs = append(allErrs, apivalidation.ValidateObjectMetaUpdate(&new.ObjectMeta, &old.ObjectMeta, field.NewPath("metadata"))...)
allErrs = append(allErrs, ValidatePodSecurityPolicySpecificAnnotations(new.Annotations, field.NewPath("metadata").Child("annotations"))...)
allErrs = append(allErrs, ValidatePodSecurityPolicySpec(&new.Spec, field.NewPath("spec"))...)
return allErrs
}
// hasCap checks for needle in haystack.
func hasCap(needle core.Capability, haystack []core.Capability) bool {
for _, c := range haystack {
if needle == c {
return true
}
}
return false
}