// Copyright 2021 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;

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

// The ciphersuites supported by S2A. The name determines the confidentiality,
// and authentication ciphers as well as the hash algorithm used for PRF in
// TLS 1.2 or HKDF in TLS 1.3. Thus, the components of the name are:
//  - AEAD -- for encryption and authentication, e.g., AES_128_GCM.
//  - Hash algorithm -- used in PRF or HKDF, e.g., SHA256.
enum Ciphersuite {
  AES_128_GCM_SHA256 = 0;
  AES_256_GCM_SHA384 = 1;
  CHACHA20_POLY1305_SHA256 = 2;
}

// The TLS versions supported by S2A's handshaker module.
enum TLSVersion {
  TLS1_2 = 0;
  TLS1_3 = 1;
}

message Identity {
  oneof identity_oneof {
    // The SPIFFE ID of a connection endpoint.
    string spiffe_id = 1;

    // The hostname of a connection endpoint.
    string hostname = 2;

    // The UID of a connection endpoint.
    string uid = 4;

    // The username of a connection endpoint. 
    string username = 5;

    // The GCP ID of a connection endpoint.
    string gcp_id = 6;
  }

  // Additional identity-specific attributes.
  map<string, string> attributes = 3;
}