rebase: update kubernetes to v1.25.0

update kubernetes to latest v1.25.0
release.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>

vendor/k8s.io/pod-security-admission/policy/check_capabilities_restricted.go

@@ -0,0 +1,145 @@
+/*
+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"
+)
+
+const (
+	capabilityAll            = "ALL"
+	capabilityNetBindService = "NET_BIND_SERVICE"
+)
+
+/*
+Containers must drop ALL, and may only add NET_BIND_SERVICE.
+
+**Restricted Fields:**
+spec.containers[*].securityContext.capabilities.drop
+spec.initContainers[*].securityContext.capabilities.drop
+
+**Allowed Values:**
+Must include "ALL"
+
+**Restricted Fields:**
+spec.containers[*].securityContext.capabilities.add
+spec.initContainers[*].securityContext.capabilities.add
+
+**Allowed Values:**
+undefined / empty
+"NET_BIND_SERVICE"
+*/
+
+func init() {
+	addCheck(CheckCapabilitiesRestricted)
+}
+
+// CheckCapabilitiesRestricted returns a restricted level check
+// that ensures ALL capabilities are dropped in 1.22+
+func CheckCapabilitiesRestricted() Check {
+	return Check{
+		ID:    "capabilities_restricted",
+		Level: api.LevelRestricted,
+		Versions: []VersionedCheck{
+			{
+				MinimumVersion:   api.MajorMinorVersion(1, 22),
+				CheckPod:         capabilitiesRestricted_1_22,
+				OverrideCheckIDs: []CheckID{checkCapabilitiesBaselineID},
+			},
+			// Starting 1.25, windows pods would be exempted from this check using pod.spec.os field when set to windows.
+			{
+				MinimumVersion:   api.MajorMinorVersion(1, 25),
+				CheckPod:         capabilitiesRestricted_1_25,
+				OverrideCheckIDs: []CheckID{checkCapabilitiesBaselineID},
+			},
+		},
+	}
+}
+
+func capabilitiesRestricted_1_22(podMetadata *metav1.ObjectMeta, podSpec *corev1.PodSpec) CheckResult {
+	var (
+		containersMissingDropAll  []string
+		containersAddingForbidden []string
+		forbiddenCapabilities     = sets.NewString()
+	)
+
+	visitContainers(podSpec, func(container *corev1.Container) {
+		if container.SecurityContext == nil || container.SecurityContext.Capabilities == nil {
+			containersMissingDropAll = append(containersMissingDropAll, container.Name)
+			return
+		}
+
+		droppedAll := false
+		for _, c := range container.SecurityContext.Capabilities.Drop {
+			if c == capabilityAll {
+				droppedAll = true
+				break
+			}
+		}
+		if !droppedAll {
+			containersMissingDropAll = append(containersMissingDropAll, container.Name)
+		}
+
+		addedForbidden := false
+		for _, c := range container.SecurityContext.Capabilities.Add {
+			if c != capabilityNetBindService {
+				addedForbidden = true
+				forbiddenCapabilities.Insert(string(c))
+			}
+		}
+		if addedForbidden {
+			containersAddingForbidden = append(containersAddingForbidden, container.Name)
+		}
+	})
+	var forbiddenDetails []string
+	if len(containersMissingDropAll) > 0 {
+		forbiddenDetails = append(forbiddenDetails, fmt.Sprintf(
+			`%s %s must set securityContext.capabilities.drop=["ALL"]`,
+			pluralize("container", "containers", len(containersMissingDropAll)),
+			joinQuote(containersMissingDropAll)))
+	}
+	if len(containersAddingForbidden) > 0 {
+		forbiddenDetails = append(forbiddenDetails, fmt.Sprintf(
+			`%s %s must not include %s in securityContext.capabilities.add`,
+			pluralize("container", "containers", len(containersAddingForbidden)),
+			joinQuote(containersAddingForbidden),
+			joinQuote(forbiddenCapabilities.List())))
+	}
+	if len(forbiddenDetails) > 0 {
+		return CheckResult{
+			Allowed:         false,
+			ForbiddenReason: "unrestricted capabilities",
+			ForbiddenDetail: strings.Join(forbiddenDetails, "; "),
+		}
+	}
+	return CheckResult{Allowed: true}
+}
+
+func capabilitiesRestricted_1_25(podMetadata *metav1.ObjectMeta, podSpec *corev1.PodSpec) CheckResult {
+	// Pod API validation would have failed if podOS == Windows and if capabilities have been set.
+	// We can admit the Windows pod even if capabilities has not been set.
+	if podSpec.OS != nil && podSpec.OS.Name == corev1.Windows {
+		return CheckResult{Allowed: true}
+	}
+	return capabilitiesRestricted_1_22(podMetadata, podSpec)
+}