sigs.k8s.io/cluster-api/bootstrap/kubeadm@v0.0.0-20191016155141-23a891785b60/controllers/token.go (about)

     1  /*
     2  Copyright 2019 The Kubernetes Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package controllers
    18  
    19  import (
    20  	"time"
    21  
    22  	"github.com/pkg/errors"
    23  	v1 "k8s.io/api/core/v1"
    24  	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
    25  	corev1 "k8s.io/client-go/kubernetes/typed/core/v1"
    26  	bootstrapapi "k8s.io/cluster-bootstrap/token/api"
    27  	bootstraputil "k8s.io/cluster-bootstrap/token/util"
    28  	clusterv1 "sigs.k8s.io/cluster-api/api/v1alpha2"
    29  	capiremote "sigs.k8s.io/cluster-api/controllers/remote"
    30  	"sigs.k8s.io/controller-runtime/pkg/client"
    31  )
    32  
    33  var (
    34  	// DefaultTokenTTL is the amount of time a bootstrap token (and therefore a KubeadmConfig) will be valid
    35  	DefaultTokenTTL = 15 * time.Minute
    36  )
    37  
    38  // ClusterSecretsClientFactory support creation of secrets client for clusters
    39  type ClusterSecretsClientFactory struct{}
    40  
    41  // NewSecretsClient returns a new client supporting SecretInterface for the cluster
    42  func (f ClusterSecretsClientFactory) NewSecretsClient(client client.Client, cluster *clusterv1.Cluster) (corev1.SecretInterface, error) {
    43  	remoteClient, err := capiremote.NewClusterClient(client, cluster)
    44  	if err != nil {
    45  		return nil, err
    46  	}
    47  
    48  	corev1Client, err := remoteClient.CoreV1()
    49  	if err != nil {
    50  		return nil, err
    51  	}
    52  
    53  	return corev1Client.Secrets(metav1.NamespaceSystem), nil
    54  }
    55  
    56  // createToken attempts to create a token with the given ID.
    57  func createToken(client corev1.SecretInterface) (string, error) {
    58  	token, err := bootstraputil.GenerateBootstrapToken()
    59  	if err != nil {
    60  		return "", errors.Wrap(err, "unable to generate bootstrap token")
    61  	}
    62  
    63  	substrs := bootstraputil.BootstrapTokenRegexp.FindStringSubmatch(token)
    64  	if len(substrs) != 3 {
    65  		return "", errors.Errorf("the bootstrap token %q was not of the form %q", token, bootstrapapi.BootstrapTokenPattern)
    66  	}
    67  	tokenID := substrs[1]
    68  	tokenSecret := substrs[2]
    69  
    70  	secretName := bootstraputil.BootstrapTokenSecretName(tokenID)
    71  	secretToken := &v1.Secret{
    72  		ObjectMeta: metav1.ObjectMeta{
    73  			Name:      secretName,
    74  			Namespace: metav1.NamespaceSystem,
    75  		},
    76  		Type: bootstrapapi.SecretTypeBootstrapToken,
    77  		Data: map[string][]byte{
    78  			bootstrapapi.BootstrapTokenIDKey:               []byte(tokenID),
    79  			bootstrapapi.BootstrapTokenSecretKey:           []byte(tokenSecret),
    80  			bootstrapapi.BootstrapTokenExpirationKey:       []byte(time.Now().UTC().Add(DefaultTokenTTL).Format(time.RFC3339)),
    81  			bootstrapapi.BootstrapTokenUsageSigningKey:     []byte("true"),
    82  			bootstrapapi.BootstrapTokenUsageAuthentication: []byte("true"),
    83  			bootstrapapi.BootstrapTokenExtraGroupsKey:      []byte("system:bootstrappers:kubeadm:default-node-token"),
    84  			bootstrapapi.BootstrapTokenDescriptionKey:      []byte("token generated by cluster-api-bootstrap-provider-kubeadm"),
    85  		},
    86  	}
    87  
    88  	if _, err = client.Create(secretToken); err != nil {
    89  		return "", err
    90  	}
    91  	return token, nil
    92  }
    93  
    94  // refreshToken extends the TTL for an existing token
    95  func refreshToken(client corev1.SecretInterface, token string) error {
    96  	substrs := bootstraputil.BootstrapTokenRegexp.FindStringSubmatch(token)
    97  	if len(substrs) != 3 {
    98  		return errors.Errorf("the bootstrap token %q was not of the form %q", token, bootstrapapi.BootstrapTokenPattern)
    99  	}
   100  	tokenID := substrs[1]
   101  
   102  	secretName := bootstraputil.BootstrapTokenSecretName(tokenID)
   103  	secret, err := client.Get(secretName, metav1.GetOptions{})
   104  	if err != nil {
   105  		return err
   106  	}
   107  
   108  	if secret.Data == nil {
   109  		return errors.Errorf("Invalid bootstrap secret %q, remove the token from the kubadm config to re-create", secretName)
   110  	}
   111  	secret.Data[bootstrapapi.BootstrapTokenExpirationKey] = []byte(time.Now().UTC().Add(DefaultTokenTTL).Format(time.RFC3339))
   112  
   113  	_, err = client.Update(secret)
   114  	return err
   115  }