blob: 23de34cf8a1818037fbc42317ff8a22d2710ab04 [file] [log] [blame]
/*
*
* Copyright 2020 gRPC 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 local implements local transport credentials.
// Local credentials reports the security level based on the type
// of connetion. If the connection is local TCP, NoSecurity will be
// reported, and if the connection is UDS, PrivacyAndIntegrity will be
// reported. If local credentials is not used in local connections
// (local TCP or UDS), it will fail.
//
// This package is EXPERIMENTAL.
package local
import (
"context"
"fmt"
"net"
"strings"
"google.golang.org/grpc/credentials"
)
// Info contains the auth information for a local connection.
// It implements the AuthInfo interface.
type Info struct {
credentials.CommonAuthInfo
}
// AuthType returns the type of Info as a string.
func (Info) AuthType() string {
return "local"
}
// localTC is the credentials required to establish a local connection.
type localTC struct {
info credentials.ProtocolInfo
}
func (c *localTC) Info() credentials.ProtocolInfo {
return c.info
}
// getSecurityLevel returns the security level for a local connection.
// It returns an error if a connection is not local.
func getSecurityLevel(network, addr string) (credentials.SecurityLevel, error) {
switch {
// Local TCP connection
case strings.HasPrefix(addr, "127."), strings.HasPrefix(addr, "[::1]:"):
return credentials.NoSecurity, nil
// UDS connection
case network == "unix":
return credentials.PrivacyAndIntegrity, nil
// Not a local connection and should fail
default:
return credentials.Invalid, fmt.Errorf("local credentials rejected connection to non-local address %q", addr)
}
}
func (*localTC) ClientHandshake(ctx context.Context, authority string, conn net.Conn) (net.Conn, credentials.AuthInfo, error) {
secLevel, err := getSecurityLevel(conn.RemoteAddr().Network(), conn.RemoteAddr().String())
if err != nil {
return nil, nil, err
}
return conn, Info{credentials.CommonAuthInfo{SecurityLevel: secLevel}}, nil
}
func (*localTC) ServerHandshake(conn net.Conn) (net.Conn, credentials.AuthInfo, error) {
secLevel, err := getSecurityLevel(conn.RemoteAddr().Network(), conn.RemoteAddr().String())
if err != nil {
return nil, nil, err
}
return conn, Info{credentials.CommonAuthInfo{SecurityLevel: secLevel}}, nil
}
// NewCredentials returns a local credential implementing credentials.TransportCredentials.
func NewCredentials() credentials.TransportCredentials {
return &localTC{
info: credentials.ProtocolInfo{
SecurityProtocol: "local",
},
}
}
// Clone makes a copy of Local credentials.
func (c *localTC) Clone() credentials.TransportCredentials {
return &localTC{info: c.info}
}
// OverrideServerName overrides the server name used to verify the hostname on the returned certificates from the server.
// Since this feature is specific to TLS (SNI + hostname verification check), it does not take any effet for local credentials.
func (c *localTC) OverrideServerName(serverNameOverride string) error {
c.info.ServerName = serverNameOverride
return nil
}