istio.io/istio@v0.0.0-20240520182934-d79c90f27776/pilot/pkg/credentials/kube/multicluster.go (about)

     1  // Copyright Istio Authors
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package kube
    16  
    17  import (
    18  	"fmt"
    19  
    20  	"istio.io/istio/pilot/pkg/credentials"
    21  	"istio.io/istio/pkg/cluster"
    22  	"istio.io/istio/pkg/kube/multicluster"
    23  )
    24  
    25  // Multicluster structure holds the remote kube Controllers and multicluster specific attributes.
    26  type Multicluster struct {
    27  	configCluster  cluster.ID
    28  	secretHandlers []func(name string, namespace string)
    29  	component      *multicluster.Component[*CredentialsController]
    30  }
    31  
    32  var _ credentials.MulticlusterController = &Multicluster{}
    33  
    34  func NewMulticluster(configCluster cluster.ID, controller multicluster.ComponentBuilder) *Multicluster {
    35  	m := &Multicluster{
    36  		configCluster: configCluster,
    37  	}
    38  
    39  	m.component = multicluster.BuildMultiClusterComponent(controller, func(cluster *multicluster.Cluster) *CredentialsController {
    40  		return NewCredentialsController(cluster.Client, m.secretHandlers)
    41  	})
    42  	return m
    43  }
    44  
    45  func (m *Multicluster) ForCluster(clusterID cluster.ID) (credentials.Controller, error) {
    46  	cc := m.component.ForCluster(clusterID)
    47  	if cc == nil {
    48  		return nil, fmt.Errorf("cluster %v is not configured", clusterID)
    49  	}
    50  	agg := &AggregateController{}
    51  	agg.controllers = []*CredentialsController{}
    52  	agg.authController = *cc
    53  	if clusterID != m.configCluster {
    54  		// If the request cluster is not the config cluster, we will append it and use it for auth
    55  		// This means we will prioritize the proxy cluster, then the config cluster for credential lookup
    56  		// Authorization will always use the proxy cluster.
    57  		agg.controllers = append(agg.controllers, *cc)
    58  	}
    59  	if cc := m.component.ForCluster(m.configCluster); cc != nil {
    60  		agg.controllers = append(agg.controllers, *cc)
    61  	}
    62  	return agg, nil
    63  }
    64  
    65  func (m *Multicluster) AddSecretHandler(h func(name string, namespace string)) {
    66  	// Intentionally no lock. The controller today requires that handlers are registered before execution and not in parallel.
    67  	m.secretHandlers = append(m.secretHandlers, h)
    68  }
    69  
    70  type AggregateController struct {
    71  	// controllers to use to look up certs. Generally this will consistent of the primary (config) cluster
    72  	// and a single remote cluster where the proxy resides
    73  	controllers    []*CredentialsController
    74  	authController *CredentialsController
    75  }
    76  
    77  var _ credentials.Controller = &AggregateController{}
    78  
    79  func (a *AggregateController) GetCertInfo(name, namespace string) (certInfo *credentials.CertInfo, err error) {
    80  	// Search through all clusters, find first non-empty result
    81  	var firstError error
    82  	for _, c := range a.controllers {
    83  		certInfo, err := c.GetCertInfo(name, namespace)
    84  		if err != nil {
    85  			if firstError == nil {
    86  				firstError = err
    87  			}
    88  		} else {
    89  			return certInfo, nil
    90  		}
    91  	}
    92  	return nil, firstError
    93  }
    94  
    95  func (a *AggregateController) GetCaCert(name, namespace string) (certInfo *credentials.CertInfo, err error) {
    96  	// Search through all clusters, find first non-empty result
    97  	var firstError error
    98  	for _, c := range a.controllers {
    99  		k, err := c.GetCaCert(name, namespace)
   100  		if err != nil {
   101  			if firstError == nil {
   102  				firstError = err
   103  			}
   104  		} else {
   105  			return k, nil
   106  		}
   107  	}
   108  	return nil, firstError
   109  }
   110  
   111  func (a *AggregateController) Authorize(serviceAccount, namespace string) error {
   112  	return a.authController.Authorize(serviceAccount, namespace)
   113  }
   114  
   115  func (a *AggregateController) AddEventHandler(f func(name string, namespace string)) {
   116  	// no ops
   117  }
   118  
   119  func (a *AggregateController) GetDockerCredential(name, namespace string) ([]byte, error) {
   120  	// Search through all clusters, find first non-empty result
   121  	var firstError error
   122  	for _, c := range a.controllers {
   123  		k, err := c.GetDockerCredential(name, namespace)
   124  		if err != nil {
   125  			if firstError == nil {
   126  				firstError = err
   127  			}
   128  		} else {
   129  			return k, nil
   130  		}
   131  	}
   132  	return nil, firstError
   133  }