// Copyright 2026 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

syntax = "proto2";

option optimize_for = LITE_RUNTIME;

package remoting.protocol;

// Message sent over the security-key data channel.
message SecurityKeyMessage {
  // Connection ID used to multiplex multiple security key connections.
  optional int32 connection_id = 1;

  // The payload data (opaque SSH Agent protocol bytes).
  // Enforced maximum size is 64KB on both host and client to prevent DoS/OOM.
  // Note: The host-side local socket (SecurityKeySocket) strictly limits
  // incoming requests to 16KB. Responses (which contain SSH certificates)
  // are typically under 8KB. A 64KB (power of two) limit provides ample
  // headroom while ensuring robust defense against memory exhaustion exploits.
  optional bytes data = 2;

  // Set to true if an error occurred and the connection should be closed.
  optional bool error = 3;
}