// Copyright 2022 Google LLC
//
// 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
//
//    https://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.

syntax = "proto3";

package s2a.proto.v2;

option go_package = "github.com/google/s2a/internal/proto/v2/common_go_proto";

// The TLS 1.0-1.2 ciphersuites that the application can negotiate when using
// S2A.
enum Ciphersuite {
  CIPHERSUITE_UNSPECIFIED = 0;
  CIPHERSUITE_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 = 1;
  CIPHERSUITE_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 = 2;
  CIPHERSUITE_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 = 3;
  CIPHERSUITE_ECDHE_RSA_WITH_AES_128_GCM_SHA256 = 4;
  CIPHERSUITE_ECDHE_RSA_WITH_AES_256_GCM_SHA384 = 5;
  CIPHERSUITE_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 = 6;
}

// The TLS versions supported by S2A's handshaker module.
enum TLSVersion {
  TLS_VERSION_UNSPECIFIED = 0;
  TLS_VERSION_1_0 = 1;
  TLS_VERSION_1_1 = 2;
  TLS_VERSION_1_2 = 3;
  TLS_VERSION_1_3 = 4;
}

// The side in the TLS connection.
enum ConnectionSide {
  CONNECTION_SIDE_UNSPECIFIED = 0;
  CONNECTION_SIDE_CLIENT = 1;
  CONNECTION_SIDE_SERVER = 2;
}

// The ALPN protocols that the application can negotiate during a TLS handshake.
enum AlpnProtocol {
  ALPN_PROTOCOL_UNSPECIFIED = 0;
  ALPN_PROTOCOL_GRPC = 1;
  ALPN_PROTOCOL_HTTP2 = 2;
  ALPN_PROTOCOL_HTTP1_1 = 3;
}