github.com/hxx258456/ccgo@v0.0.5-0.20230213014102-48b35f46f66f/grpc/credentials/google/xds.go (about)

     1  /*
     2   *
     3   * Copyright 2021 gRPC authors.
     4   *
     5   * Licensed under the Apache License, Version 2.0 (the "License");
     6   * you may not use this file except in compliance with the License.
     7   * You may obtain a copy of the License at
     8   *
     9   *     http://www.apache.org/licenses/LICENSE-2.0
    10   *
    11   * Unless required by applicable law or agreed to in writing, software
    12   * distributed under the License is distributed on an "AS IS" BASIS,
    13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    14   * See the License for the specific language governing permissions and
    15   * limitations under the License.
    16   *
    17   */
    18  
    19  package google
    20  
    21  import (
    22  	"context"
    23  	"net"
    24  	"strings"
    25  
    26  	"github.com/hxx258456/ccgo/grpc/credentials"
    27  	"github.com/hxx258456/ccgo/grpc/internal"
    28  )
    29  
    30  const cfeClusterNamePrefix = "google_cfe_"
    31  
    32  // clusterTransportCreds is a combo of TLS + ALTS.
    33  //
    34  // On the client, ClientHandshake picks TLS or ALTS based on address attributes.
    35  // - if attributes has cluster name
    36  //   - if cluster name has prefix "google_cfe_", use TLS
    37  //   - otherwise, use ALTS
    38  // - else, do TLS
    39  //
    40  // On the server, ServerHandshake always does TLS.
    41  type clusterTransportCreds struct {
    42  	tls  credentials.TransportCredentials
    43  	alts credentials.TransportCredentials
    44  }
    45  
    46  func newClusterTransportCreds(tls, alts credentials.TransportCredentials) *clusterTransportCreds {
    47  	return &clusterTransportCreds{
    48  		tls:  tls,
    49  		alts: alts,
    50  	}
    51  }
    52  
    53  func (c *clusterTransportCreds) ClientHandshake(ctx context.Context, authority string, rawConn net.Conn) (net.Conn, credentials.AuthInfo, error) {
    54  	chi := credentials.ClientHandshakeInfoFromContext(ctx)
    55  	if chi.Attributes == nil {
    56  		return c.tls.ClientHandshake(ctx, authority, rawConn)
    57  	}
    58  	cn, ok := internal.GetXDSHandshakeClusterName(chi.Attributes)
    59  	if !ok || strings.HasPrefix(cn, cfeClusterNamePrefix) {
    60  		return c.tls.ClientHandshake(ctx, authority, rawConn)
    61  	}
    62  	// If attributes have cluster name, and cluster name is not cfe, it's a
    63  	// backend address, use ALTS.
    64  	return c.alts.ClientHandshake(ctx, authority, rawConn)
    65  }
    66  
    67  func (c *clusterTransportCreds) ServerHandshake(conn net.Conn) (net.Conn, credentials.AuthInfo, error) {
    68  	return c.tls.ServerHandshake(conn)
    69  }
    70  
    71  func (c *clusterTransportCreds) Info() credentials.ProtocolInfo {
    72  	// TODO: this always returns tls.Info now, because we don't have a cluster
    73  	// name to check when this method is called. This method doesn't affect
    74  	// anything important now. We may want to revisit this if it becomes more
    75  	// important later.
    76  	return c.tls.Info()
    77  }
    78  
    79  func (c *clusterTransportCreds) Clone() credentials.TransportCredentials {
    80  	return &clusterTransportCreds{
    81  		tls:  c.tls.Clone(),
    82  		alts: c.alts.Clone(),
    83  	}
    84  }
    85  
    86  func (c *clusterTransportCreds) OverrideServerName(s string) error {
    87  	if err := c.tls.OverrideServerName(s); err != nil {
    88  		return err
    89  	}
    90  	return c.alts.OverrideServerName(s)
    91  }