// Copyright 2017 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

module media.mojom;

// An interface that helps proxy part of ContentDecryptionModule (CDM)
// functionalities to a different entity, e.g. hardware CDM modules.
// In general, the interpretation of the method and callback parameters are
// protocol dependent.
// CdmProxy implementation is hosted in the GPU process.
interface CdmProxy {
  // See media/cdm/cdm_proxy.h.
  [Native]
  enum Status;

  // See media/cdm/cdm_proxy.h.
  [Native]
  enum Protocol;

  // See media/cdm/cdm_proxy.h.
  [Native]
  enum Function;

  // Initializes the proxy.
  // If the proxy created a crypto session, then the ID for the crypto session
  // is |crypto_session_id|.
  // |cdm_id| can be used to connect the remote media pipeline and CdmProxy.
  Initialize(associated CdmProxyClient client) => (Status status,
                                                   Protocol protocol,
                                                   uint32 crypto_session_id,
                                                   int32 cdm_id);

  // Processes and updates the state of the proxy.
  // |function| specifies what type of function to use.
  // |crypto_session_id| is a value returned from Initialize() or
  // CreateMediaCryptoSessions().
  // |input_data| is the input data to be processed.
  // |output_data_size| is the expected size of |output_data|. Some protocols
  // require this field in order to determine the size of the output, but some
  // may completely ignore it.
  // The output data is passed back in |output_data|.
  Process(Function function,
          uint32 crypto_session_id,
          array<uint8> input_data,
          uint32 output_data_size) => (Status status,
                                       array<uint8> output_data);

  // Creates a crypto session for handling media.
  // If extra data has to be passed to further setup the media crypto session,
  // pass the data as |input_data|.
  // |crypto_session_id| is the ID for the crypto session.
  // |output_data| is extra value, if any.
  CreateMediaCryptoSession(array<uint8> input_data) => (
      Status status, uint32 crypto_session_id, uint64 output_data);

  // Sets a key in the proxy.
  // |crypto_session_id| is the crypto session for decryption.
  // |key_id| is the ID of the key.
  // |key_blob| is the opaque key blob for decrypting or decoding.
  SetKey(uint32 crypto_session_id, array<uint8> key_id, array<uint8> key_blob);

  // Removes a key from the proxy.
  // |crypto_session_id| is the crypto session for decryption.
  // |key_id| is the ID of the key.
  RemoveKey(uint32 crypto_session_id, array<uint8> key_id);
};

// Client of CdmProxy.
// CdmProxyClient is running in the fully sandboxed CDM (e.g. utility) process.
interface CdmProxyClient {
  // Notifies the client that there has been a hardware reset.
  NotifyHardwareReset();
};