visitpod.go

/*
Copyright 2015 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.
*/

// This code is directly lifted from the Kubernetes codebase in order to avoid relying on the k8s.io/kubernetes package.
// For reference:
// https://github.com/kubernetes/kubernetes/blob/release-1.26/pkg/api/v1/pod/util.go

package lifted

import (
	corev1 "k8s.io/api/core/v1"
)

// +lifted:source=https://github.com/kubernetes/kubernetes/blob/release-1.26/pkg/api/v1/pod/util.go#L51-L61

// ContainerType signifies container type
type ContainerType int

const (
	// Containers is for normal containers
	Containers ContainerType = 1 << iota
	// InitContainers is for init containers
	InitContainers
	// EphemeralContainers is for ephemeral containers
	EphemeralContainers
)

// +lifted:source=https://github.com/kubernetes/kubernetes/blob/release-1.26/pkg/api/v1/pod/util.go#L63-L64

// AllContainers specifies that all containers be visited
const AllContainers ContainerType = InitContainers | Containers | EphemeralContainers

// +lifted:source=https://github.com/kubernetes/kubernetes/blob/release-1.26/pkg/api/v1/pod/util.go#L72-L74

// ContainerVisitor is called with each container spec, and returns true
// if visiting should continue.
type ContainerVisitor func(container *corev1.Container, containerType ContainerType) (shouldContinue bool)

// +lifted:source=https://github.com/kubernetes/kubernetes/blob/release-1.26/pkg/api/v1/pod/util.go#L76-L77

// Visitor is called with each object name, and returns true if visiting should continue
type Visitor func(name string) (shouldContinue bool)

// +lifted:source=https://github.com/kubernetes/kubernetes/blob/release-1.26/pkg/api/v1/pod/util.go#L79-L88

func skipEmptyNames(visitor Visitor) Visitor {
	return func(name string) bool {
		if len(name) == 0 {
			// continue visiting
			return true
		}
		// delegate to visitor
		return visitor(name)
	}
}

// +lifted:source=https://github.com/kubernetes/kubernetes/blob/release-1.26/pkg/api/v1/pod/util.go#L79-L88

// VisitContainers invokes the visitor function with a pointer to every container
// spec in the given pod spec with type set in mask. If visitor returns false,
// visiting is short-circuited. VisitContainers returns true if visiting completes,
// false if visiting was short-circuited.
func VisitContainers(podSpec *corev1.PodSpec, mask ContainerType, visitor ContainerVisitor) bool {
	if mask&InitContainers != 0 {
		for i := range podSpec.InitContainers {
			if !visitor(&podSpec.InitContainers[i], InitContainers) {
				return false
			}
		}
	}
	if mask&Containers != 0 {
		for i := range podSpec.Containers {
			if !visitor(&podSpec.Containers[i], Containers) {
				return false
			}
		}
	}
	if mask&EphemeralContainers != 0 {
		for i := range podSpec.EphemeralContainers {
			if !visitor((*corev1.Container)(&podSpec.EphemeralContainers[i].EphemeralContainerCommon), EphemeralContainers) {
				return false
			}
		}
	}
	return true
}

// +lifted:source=https://github.com/kubernetes/kubernetes/blob/release-1.26/pkg/api/v1/pod/util.go#L119-L189

// VisitPodSecretNames invokes the visitor function with the name of every secret
// referenced by the pod spec. If visitor returns false, visiting is short-circuited.
// Transitive references (e.g. pod -> pvc -> pv -> secret) are not visited.
// Returns true if visiting completed, false if visiting was short-circuited.
//
//nolint:gocyclo
func VisitPodSecretNames(pod *corev1.Pod, visitor Visitor) bool {
	visitor = skipEmptyNames(visitor)
	for _, reference := range pod.Spec.ImagePullSecrets {
		if !visitor(reference.Name) {
			return false
		}
	}
	VisitContainers(&pod.Spec, AllContainers, func(c *corev1.Container, containerType ContainerType) bool {
		return visitContainerSecretNames(c, visitor)
	})
	var source *corev1.VolumeSource

	for i := range pod.Spec.Volumes {
		source = &pod.Spec.Volumes[i].VolumeSource
		switch {
		case source.AzureFile != nil:
			if len(source.AzureFile.SecretName) > 0 && !visitor(source.AzureFile.SecretName) {
				return false
			}
		case source.CephFS != nil:
			if source.CephFS.SecretRef != nil && !visitor(source.CephFS.SecretRef.Name) {
				return false
			}
		case source.Cinder != nil:
			if source.Cinder.SecretRef != nil && !visitor(source.Cinder.SecretRef.Name) {
				return false
			}
		case source.FlexVolume != nil:
			if source.FlexVolume.SecretRef != nil && !visitor(source.FlexVolume.SecretRef.Name) {
				return false
			}
		case source.Projected != nil:
			for j := range source.Projected.Sources {
				if source.Projected.Sources[j].Secret != nil {
					if !visitor(source.Projected.Sources[j].Secret.Name) {
						return false
					}
				}
			}
		case source.RBD != nil:
			if source.RBD.SecretRef != nil && !visitor(source.RBD.SecretRef.Name) {
				return false
			}
		case source.Secret != nil:
			if !visitor(source.Secret.SecretName) {
				return false
			}
		case source.ScaleIO != nil:
			if source.ScaleIO.SecretRef != nil && !visitor(source.ScaleIO.SecretRef.Name) {
				return false
			}
		case source.ISCSI != nil:
			if source.ISCSI.SecretRef != nil && !visitor(source.ISCSI.SecretRef.Name) {
				return false
			}
		case source.StorageOS != nil:
			if source.StorageOS.SecretRef != nil && !visitor(source.StorageOS.SecretRef.Name) {
				return false
			}
		case source.CSI != nil:
			if source.CSI.NodePublishSecretRef != nil && !visitor(source.CSI.NodePublishSecretRef.Name) {
				return false
			}
		}
	}
	return true
}

// +lifted:source=https://github.com/kubernetes/kubernetes/blob/release-1.26/pkg/api/v1/pod/util.go#L191-L208

func visitContainerSecretNames(container *corev1.Container, visitor Visitor) bool {
	for _, env := range container.EnvFrom {
		if env.SecretRef != nil {
			if !visitor(env.SecretRef.Name) {
				return false
			}
		}
	}
	for _, envVar := range container.Env {
		if envVar.ValueFrom != nil && envVar.ValueFrom.SecretKeyRef != nil {
			if !visitor(envVar.ValueFrom.SecretKeyRef.Name) {
				return false
			}
		}
	}
	return true
}

// +lifted:source=https://github.com/kubernetes/kubernetes/blob/release-1.26/pkg/api/v1/pod/util.go#L210-L238

// VisitPodConfigmapNames invokes the visitor function with the name of every configmap
// referenced by the pod spec. If visitor returns false, visiting is short-circuited.
// Transitive references (e.g. pod -> pvc -> pv -> secret) are not visited.
// Returns true if visiting completed, false if visiting was short-circuited.
func VisitPodConfigmapNames(pod *corev1.Pod, visitor Visitor) bool {
	visitor = skipEmptyNames(visitor)
	VisitContainers(&pod.Spec, AllContainers, func(c *corev1.Container, containerType ContainerType) bool {
		return visitContainerConfigmapNames(c, visitor)
	})
	var source *corev1.VolumeSource
	for i := range pod.Spec.Volumes {
		source = &pod.Spec.Volumes[i].VolumeSource
		switch {
		case source.Projected != nil:
			for j := range source.Projected.Sources {
				if source.Projected.Sources[j].ConfigMap != nil {
					if !visitor(source.Projected.Sources[j].ConfigMap.Name) {
						return false
					}
				}
			}
		case source.ConfigMap != nil:
			if !visitor(source.ConfigMap.Name) {
				return false
			}
		}
	}
	return true
}

// +lifted:source=https://github.com/kubernetes/kubernetes/blob/release-1.26/pkg/api/v1/pod/util.go#L240-L257

// visitContainerConfigmapNames returns true unless the visitor returned false when invoked with a configmap reference
func visitContainerConfigmapNames(container *corev1.Container, visitor Visitor) bool {
	for _, env := range container.EnvFrom {
		if env.ConfigMapRef != nil {
			if !visitor(env.ConfigMapRef.Name) {
				return false
			}
		}
	}
	for _, envVar := range container.Env {
		if envVar.ValueFrom != nil && envVar.ValueFrom.ConfigMapKeyRef != nil {
			if !visitor(envVar.ValueFrom.ConfigMapKeyRef.Name) {
				return false
			}
		}
	}
	return true
}