ceph-csi/vendor/k8s.io/pod-security-admission/policy/check_seLinuxOptions.go

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/*
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"
"strings"
corev1 "k8s.io/api/core/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/util/sets"
"k8s.io/pod-security-admission/api"
)
/*
Setting the SELinux type is restricted, and setting a custom SELinux user or role option is forbidden.
**Restricted Fields:**
spec.securityContext.seLinuxOptions.type
spec.containers[*].securityContext.seLinuxOptions.type
spec.initContainers[*].securityContext.seLinuxOptions.type
**Allowed Values:**
undefined/empty
container_t
container_init_t
container_kvm_t
**Restricted Fields:**
spec.securityContext.seLinuxOptions.user
spec.containers[*].securityContext.seLinuxOptions.user
spec.initContainers[*].securityContext.seLinuxOptions.user
spec.securityContext.seLinuxOptions.role
spec.containers[*].securityContext.seLinuxOptions.role
spec.initContainers[*].securityContext.seLinuxOptions.role
**Allowed Values:** undefined/empty
*/
func init() {
addCheck(CheckSELinuxOptions)
}
// CheckSELinuxOptions returns a baseline level check
// that limits seLinuxOptions type, user, and role values in 1.0+
func CheckSELinuxOptions() Check {
return Check{
ID: "seLinuxOptions",
Level: api.LevelBaseline,
Versions: []VersionedCheck{
{
MinimumVersion: api.MajorMinorVersion(1, 0),
CheckPod: seLinuxOptions_1_0,
},
},
}
}
var (
selinux_allowed_types_1_0 = sets.NewString("", "container_t", "container_init_t", "container_kvm_t")
)
func seLinuxOptions_1_0(podMetadata *metav1.ObjectMeta, podSpec *corev1.PodSpec) CheckResult {
var (
// sources that set bad seLinuxOptions
badSetters []string
// invalid type values set
badTypes = sets.NewString()
// was user set?
setUser = false
// was role set?
setRole = false
)
validSELinuxOptions := func(opts *corev1.SELinuxOptions) bool {
valid := true
if !selinux_allowed_types_1_0.Has(opts.Type) {
valid = false
badTypes.Insert(opts.Type)
}
if len(opts.User) > 0 {
valid = false
setUser = true
}
if len(opts.Role) > 0 {
valid = false
setRole = true
}
return valid
}
if podSpec.SecurityContext != nil && podSpec.SecurityContext.SELinuxOptions != nil {
if !validSELinuxOptions(podSpec.SecurityContext.SELinuxOptions) {
badSetters = append(badSetters, "pod")
}
}
var badContainers []string
visitContainers(podSpec, func(container *corev1.Container) {
if container.SecurityContext != nil && container.SecurityContext.SELinuxOptions != nil {
if !validSELinuxOptions(container.SecurityContext.SELinuxOptions) {
badContainers = append(badContainers, container.Name)
}
}
})
if len(badContainers) > 0 {
badSetters = append(
badSetters,
fmt.Sprintf(
"%s %s",
pluralize("container", "containers", len(badContainers)),
joinQuote(badContainers),
),
)
}
if len(badSetters) > 0 {
var badData []string
if len(badTypes) > 0 {
badData = append(badData, fmt.Sprintf(
"%s %s",
pluralize("type", "types", len(badTypes)),
joinQuote(badTypes.List()),
))
}
if setUser {
badData = append(badData, "user may not be set")
}
if setRole {
badData = append(badData, "role may not be set")
}
return CheckResult{
Allowed: false,
ForbiddenReason: "seLinuxOptions",
ForbiddenDetail: fmt.Sprintf(
`%s set forbidden securityContext.seLinuxOptions: %s`,
strings.Join(badSetters, " and "),
strings.Join(badData, "; "),
),
}
}
return CheckResult{Allowed: true}
}