vitess.io/vitess@v0.16.2/go/vt/servenv/grpc_server_auth_mtls.go (about)

     1  /*
     2  Copyright 2019 The Vitess 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 servenv
    18  
    19  import (
    20  	"context"
    21  	"strings"
    22  
    23  	"github.com/spf13/pflag"
    24  	"google.golang.org/grpc/codes"
    25  	"google.golang.org/grpc/credentials"
    26  	"google.golang.org/grpc/peer"
    27  	"google.golang.org/grpc/status"
    28  
    29  	"vitess.io/vitess/go/vt/log"
    30  )
    31  
    32  var (
    33  	// clientCertSubstrings list of substrings of at least one of the client certificate names to use during authorization
    34  	clientCertSubstrings string
    35  	// MtlsAuthPlugin implements AuthPlugin interface
    36  	_ Authenticator = (*MtlsAuthPlugin)(nil)
    37  )
    38  
    39  func registerGRPCServerAuthMTLSFlags(fs *pflag.FlagSet) {
    40  	fs.StringVar(&clientCertSubstrings, "grpc_auth_mtls_allowed_substrings", clientCertSubstrings, "List of substrings of at least one of the client certificate names (separated by colon).")
    41  }
    42  
    43  // MtlsAuthPlugin  implements static username/password authentication for grpc. It contains an array of username/passwords
    44  // that will be authorized to connect to the grpc server.
    45  type MtlsAuthPlugin struct {
    46  	clientCertSubstrings []string
    47  }
    48  
    49  // Authenticate implements Authenticator interface. This method will be used inside a middleware in grpc_server to authenticate
    50  // incoming requests.
    51  func (ma *MtlsAuthPlugin) Authenticate(ctx context.Context, fullMethod string) (context.Context, error) {
    52  	p, ok := peer.FromContext(ctx)
    53  	if !ok {
    54  		return nil, status.Errorf(codes.Unauthenticated, "no peer connection info")
    55  	}
    56  	tlsInfo, ok := p.AuthInfo.(credentials.TLSInfo)
    57  	if !ok {
    58  		return nil, status.Errorf(codes.Unauthenticated, "not connected via TLS")
    59  	}
    60  	for _, substring := range ma.clientCertSubstrings {
    61  		for _, cert := range tlsInfo.State.PeerCertificates {
    62  			if strings.Contains(cert.Subject.String(), substring) {
    63  				return ctx, nil
    64  			}
    65  		}
    66  	}
    67  	return nil, status.Errorf(codes.Unauthenticated, "client certificate not authorized")
    68  }
    69  
    70  func mtlsAuthPluginInitializer() (Authenticator, error) {
    71  	mtlsAuthPlugin := &MtlsAuthPlugin{
    72  		clientCertSubstrings: strings.Split(clientCertSubstrings, ":"),
    73  	}
    74  	log.Infof("mtls auth plugin have initialized successfully with allowed client cert name substrings of %v", clientCertSubstrings)
    75  	return mtlsAuthPlugin, nil
    76  }
    77  
    78  // ClientCertSubstrings returns the value of the
    79  // `--grpc_auth_mtls_allowed_substrings` flag.
    80  func ClientCertSubstrings() string {
    81  	return clientCertSubstrings
    82  }
    83  
    84  func init() {
    85  	RegisterAuthPlugin("mtls", mtlsAuthPluginInitializer)
    86  	grpcAuthServerFlagHooks = append(grpcAuthServerFlagHooks, registerGRPCServerAuthMTLSFlags)
    87  }