mirror of
https://github.com/k3s-io/kubernetes.git
synced 2025-07-29 14:37:00 +00:00
PodSecurity: check: addCapabilities
This commit is contained in:
Jordan Liggitt
parent
3733e209c9
commit
93c6f8969a
@ -0,0 +1,92 @@
|
||||
/*
|
||||
Copyright 2021 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 policy
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
|
||||
corev1 "k8s.io/api/core/v1"
|
||||
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
|
||||
"k8s.io/apimachinery/pkg/util/sets"
|
||||
"k8s.io/apimachinery/pkg/util/validation/field"
|
||||
"k8s.io/pod-security-admission/api"
|
||||
)
|
||||
|
||||
func init() {
|
||||
addCheck(CheckAddCapabilities)
|
||||
}
|
||||
|
||||
// CheckAddCapabilities returns a baseline level check
|
||||
// that limits the capabilities that can be added in 1.0+
|
||||
func CheckAddCapabilities() Check {
|
||||
return Check{
|
||||
ID: "addCapabilities",
|
||||
Level: api.LevelBaseline,
|
||||
Versions: []VersionedCheck{
|
||||
{
|
||||
MinimumVersion: api.MajorMinorVersion(1, 0),
|
||||
CheckPod: addCapabilities_1_0,
|
||||
},
|
||||
},
|
||||
}
|
||||
}
|
||||
|
||||
var (
|
||||
capabilities_allowed_1_0 = sets.NewString(
|
||||
"AUDIT_WRITE",
|
||||
"CHOWN",
|
||||
"DAC_OVERRIDE",
|
||||
"FOWNER",
|
||||
"FSETID",
|
||||
"KILL",
|
||||
"MKNOD",
|
||||
"NET_BIND_SERVICE",
|
||||
"SETFCAP",
|
||||
"SETGID",
|
||||
"SETPCAP",
|
||||
"SETUID",
|
||||
"SYS_CHROOT",
|
||||
)
|
||||
)
|
||||
|
||||
func addCapabilities_1_0(podMetadata *metav1.ObjectMeta, podSpec *corev1.PodSpec) CheckResult {
|
||||
forbiddenContainers := sets.NewString()
|
||||
forbiddenCapabilities := sets.NewString()
|
||||
visitContainersWithPath(podSpec, field.NewPath("spec"), func(container *corev1.Container, path *field.Path) {
|
||||
if container.SecurityContext != nil && container.SecurityContext.Capabilities != nil {
|
||||
for _, c := range container.SecurityContext.Capabilities.Add {
|
||||
if !capabilities_allowed_1_0.Has(string(c)) {
|
||||
forbiddenContainers.Insert(container.Name)
|
||||
forbiddenCapabilities.Insert(string(c))
|
||||
}
|
||||
}
|
||||
}
|
||||
})
|
||||
|
||||
if len(forbiddenCapabilities) > 0 {
|
||||
return CheckResult{
|
||||
Allowed: false,
|
||||
ForbiddenReason: "forbidden capabilities",
|
||||
ForbiddenDetail: fmt.Sprintf(
|
||||
"containers %q added %q",
|
||||
forbiddenContainers.List(),
|
||||
forbiddenCapabilities.List(),
|
||||
),
|
||||
}
|
||||
}
|
||||
return CheckResult{Allowed: true}
|
||||
}
|
||||
@ -0,0 +1,106 @@
|
||||
/*
|
||||
Copyright 2021 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 test
|
||||
|
||||
import (
|
||||
corev1 "k8s.io/api/core/v1"
|
||||
"k8s.io/pod-security-admission/api"
|
||||
)
|
||||
|
||||
/*
|
||||
TODO: include field paths in reflect-based unit test
|
||||
|
||||
containerFields: []string{
|
||||
`securityContext.capabilities.add`,
|
||||
},
|
||||
*/
|
||||
|
||||
// ensureCapabilities ensures the pod and all initContainers and containers have a non-nil capabilities.
|
||||
func ensureCapabilities(p *corev1.Pod) *corev1.Pod {
|
||||
p = ensureSecurityContext(p)
|
||||
for i := range p.Spec.Containers {
|
||||
if p.Spec.Containers[i].SecurityContext.Capabilities == nil {
|
||||
p.Spec.Containers[i].SecurityContext.Capabilities = &corev1.Capabilities{}
|
||||
}
|
||||
}
|
||||
for i := range p.Spec.InitContainers {
|
||||
if p.Spec.InitContainers[i].SecurityContext.Capabilities == nil {
|
||||
p.Spec.InitContainers[i].SecurityContext.Capabilities = &corev1.Capabilities{}
|
||||
}
|
||||
}
|
||||
return p
|
||||
}
|
||||
|
||||
func init() {
|
||||
fixtureData_1_0 := fixtureGenerator{
|
||||
expectErrorSubstring: "forbidden capabilities",
|
||||
generatePass: func(p *corev1.Pod) []*corev1.Pod {
|
||||
p = ensureCapabilities(p)
|
||||
return []*corev1.Pod{
|
||||
// all allowed capabilities
|
||||
tweak(p, func(p *corev1.Pod) {
|
||||
p.Spec.Containers[0].SecurityContext.Capabilities.Add = []corev1.Capability{
|
||||
"AUDIT_WRITE", "CHOWN", "DAC_OVERRIDE", "FOWNER", "FSETID", "KILL", "MKNOD", "NET_BIND_SERVICE", "SETFCAP", "SETGID", "SETPCAP", "SETUID", "SYS_CHROOT",
|
||||
}
|
||||
}),
|
||||
tweak(p, func(p *corev1.Pod) {
|
||||
p.Spec.InitContainers[0].SecurityContext.Capabilities.Add = []corev1.Capability{
|
||||
"AUDIT_WRITE", "CHOWN", "DAC_OVERRIDE", "FOWNER", "FSETID", "KILL", "MKNOD", "NET_BIND_SERVICE", "SETFCAP", "SETGID", "SETPCAP", "SETUID", "SYS_CHROOT",
|
||||
}
|
||||
}),
|
||||
}
|
||||
},
|
||||
generateFail: func(p *corev1.Pod) []*corev1.Pod {
|
||||
p = ensureCapabilities(p)
|
||||
return []*corev1.Pod{
|
||||
// NET_RAW
|
||||
tweak(p, func(p *corev1.Pod) {
|
||||
p.Spec.Containers[0].SecurityContext.Capabilities.Add = []corev1.Capability{"NET_RAW"}
|
||||
}),
|
||||
tweak(p, func(p *corev1.Pod) {
|
||||
p.Spec.InitContainers[0].SecurityContext.Capabilities.Add = []corev1.Capability{"NET_RAW"}
|
||||
}),
|
||||
// case-difference
|
||||
tweak(p, func(p *corev1.Pod) {
|
||||
p.Spec.Containers[0].SecurityContext.Capabilities.Add = []corev1.Capability{"chown"}
|
||||
}),
|
||||
tweak(p, func(p *corev1.Pod) {
|
||||
p.Spec.InitContainers[0].SecurityContext.Capabilities.Add = []corev1.Capability{"chown"}
|
||||
}),
|
||||
// unknown capability
|
||||
tweak(p, func(p *corev1.Pod) {
|
||||
p.Spec.Containers[0].SecurityContext.Capabilities.Add = []corev1.Capability{"bogus"}
|
||||
}),
|
||||
tweak(p, func(p *corev1.Pod) {
|
||||
p.Spec.InitContainers[0].SecurityContext.Capabilities.Add = []corev1.Capability{"bogus"}
|
||||
}),
|
||||
// CAP_ prefix
|
||||
tweak(p, func(p *corev1.Pod) {
|
||||
p.Spec.Containers[0].SecurityContext.Capabilities.Add = []corev1.Capability{"CAP_CHOWN"}
|
||||
}),
|
||||
tweak(p, func(p *corev1.Pod) {
|
||||
p.Spec.InitContainers[0].SecurityContext.Capabilities.Add = []corev1.Capability{"CAP_CHOWN"}
|
||||
}),
|
||||
}
|
||||
},
|
||||
}
|
||||
|
||||
registerFixtureGenerator(
|
||||
fixtureKey{level: api.LevelBaseline, version: api.MajorMinorVersion(1, 0), check: "addCapabilities"},
|
||||
fixtureData_1_0,
|
||||
)
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user