1 // Copyright 2014 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 syntax = "proto2"; 6 7 option optimize_for = LITE_RUNTIME; 8 9 package extensions.core_api.cast_channel; 10 11 message CastMessage { 12 // Always pass a version of the protocol for future compatibility 13 // requirements. 14 enum ProtocolVersion { 15 CASTV2_1_0 = 0; 16 } 17 required ProtocolVersion protocol_version = 1; 18 19 // source and destination ids identify the origin and destination of the 20 // message. They are used to route messages between endpoints that share a 21 // device-to-device channel. 22 // 23 // For messages between applications: 24 // - The sender application id is a unique identifier generated on behalf of 25 // the sender application. 26 // - The receiver id is always the the session id for the application. 27 // 28 // For messages to or from the sender or receiver platform, the special ids 29 // 'sender-0' and 'receiver-0' can be used. 30 // 31 // For messages intended for all endpoints using a given channel, the 32 // wildcard destination_id '*' can be used. 33 required string source_id = 2; 34 required string destination_id = 3; 35 36 // This is the core multiplexing key. All messages are sent on a namespace 37 // and endpoints sharing a channel listen on one or more namespaces. The 38 // namespace defines the protocol and semantics of the message. 39 required string namespace = 4; 40 41 // Encoding and payload info follows. 42 43 // What type of data do we have in this message. 44 enum PayloadType { 45 STRING = 0; 46 BINARY = 1; 47 } 48 required PayloadType payload_type = 5; 49 50 // Depending on payload_type, exactly one of the following optional fields 51 // will always be set. 52 optional string payload_utf8 = 6; 53 optional bytes payload_binary = 7; 54 } 55 56 enum SignatureAlgorithm { 57 UNSPECIFIED = 0; 58 RSASSA_PKCS1v15 = 1; 59 RSASSA_PSS = 2; 60 } 61 62 // Messages for authentication protocol between a sender and a receiver. 63 message AuthChallenge { 64 optional SignatureAlgorithm signature_algorithm = 1 65 [default = RSASSA_PKCS1v15]; 66 } 67 68 message AuthResponse { 69 required bytes signature = 1; 70 required bytes client_auth_certificate = 2; 71 repeated bytes intermediate_certificate = 3; 72 optional SignatureAlgorithm signature_algorithm = 4 73 [default = RSASSA_PKCS1v15]; 74 } 75 76 message AuthError { 77 enum ErrorType { 78 INTERNAL_ERROR = 0; 79 NO_TLS = 1; // The underlying connection is not TLS 80 SIGNATURE_ALGORITHM_UNAVAILABLE = 2; 81 } 82 required ErrorType error_type = 1; 83 } 84 85 message DeviceAuthMessage { 86 // Request fields 87 optional AuthChallenge challenge = 1; 88 // Response fields 89 optional AuthResponse response = 2; 90 optional AuthError error = 3; 91 } 92