identity.go

/*
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 identity

import (
	"context"
	"errors"
	"fmt"
	"strings"

	apiv1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/labels"
	"sigs.k8s.io/controller-runtime/pkg/client"

	infrav1 "sigs.k8s.io/cluster-api-provider-vsphere/apis/v1beta1"
)

const (
	UsernameKey = "username"
	PasswordKey = "password"
)

type Credentials struct {
	Username string
	Password string
}

func GetCredentials(ctx context.Context, c client.Client, cluster *infrav1.VSphereCluster, controllerNamespace string) (*Credentials, error) {
	if err := validateInputs(c, cluster); err != nil {
		return nil, err
	}

	ref := cluster.Spec.IdentityRef
	secret := &apiv1.Secret{}
	var secretKey client.ObjectKey

	switch ref.Kind {
	case infrav1.SecretKind:
		secretKey = client.ObjectKey{
			Namespace: cluster.Namespace,
			Name:      ref.Name,
		}
	case infrav1.VSphereClusterIdentityKind:
		identity := &infrav1.VSphereClusterIdentity{}
		key := client.ObjectKey{
			Name: ref.Name,
		}
		if err := c.Get(ctx, key, identity); err != nil {
			return nil, err
		}

		if !identity.Status.Ready {
			return nil, errors.New("identity isn't ready to be used yet")
		}

		if identity.Spec.AllowedNamespaces == nil {
			return nil, errors.New("allowedNamespaces set to nil, no namespaces are allowed to use this identity")
		}

		selector, err := metav1.LabelSelectorAsSelector(&identity.Spec.AllowedNamespaces.Selector)
		if err != nil {
			return nil, errors.New("failed to build selector")
		}

		ns := &apiv1.Namespace{}
		nsKey := client.ObjectKey{
			Name: cluster.Namespace,
		}
		if err := c.Get(ctx, nsKey, ns); err != nil {
			return nil, err
		}
		if !selector.Matches(labels.Set(ns.GetLabels())) {
			return nil, fmt.Errorf("namespace %s is not allowed to use specifified identity", cluster.Namespace)
		}

		secretKey = client.ObjectKey{
			Name:      identity.Spec.SecretName,
			Namespace: controllerNamespace,
		}
	default:
		return nil, fmt.Errorf("unknown type %s used for Identity", ref.Kind)
	}

	if err := c.Get(ctx, secretKey, secret); err != nil {
		return nil, err
	}

	credentials := &Credentials{
		Username: getData(secret, UsernameKey),
		Password: getData(secret, PasswordKey),
	}

	return credentials, nil
}

func validateInputs(c client.Client, cluster *infrav1.VSphereCluster) error {
	if c == nil {
		return errors.New("kubernetes client is required")
	}
	if cluster == nil {
		return errors.New("vsphere cluster is required")
	}
	ref := cluster.Spec.IdentityRef
	if ref == nil {
		return errors.New("IdentityRef is required")
	}
	return nil
}

func IsSecretIdentity(cluster *infrav1.VSphereCluster) bool {
	if cluster == nil || cluster.Spec.IdentityRef == nil {
		return false
	}

	return cluster.Spec.IdentityRef.Kind == infrav1.SecretKind
}

func IsOwnedByIdentityOrCluster(ownerReferences []metav1.OwnerReference) bool {
	if len(ownerReferences) > 0 {
		for _, ownerReference := range ownerReferences {
			if !strings.Contains(ownerReference.APIVersion, infrav1.GroupName+"/") {
				continue
			}
			if ownerReference.Kind == "VSphereCluster" || ownerReference.Kind == "VSphereClusterIdentity" {
				return true
			}
		}
	}
	return false
}

func getData(secret *apiv1.Secret, key string) string {
	if secret.Data == nil {
		return ""
	}
	if val, ok := secret.Data[key]; ok {
		return string(val)
	}
	return ""
}