| /* |
| * |
| * 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 |
| } |