shaka-packager/packager/media/base/key_source.h

107 lines
4.0 KiB
C++

// Copyright 2014 Google Inc. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file or at
// https://developers.google.com/open-source/licenses/bsd
#ifndef PACKAGER_MEDIA_BASE_KEY_SOURCE_H_
#define PACKAGER_MEDIA_BASE_KEY_SOURCE_H_
#include <map>
#include <memory>
#include <string>
#include <vector>
#include "packager/media/base/fourccs.h"
#include "packager/media/base/protection_system_specific_info.h"
#include "packager/media/base/pssh_generator.h"
#include "packager/status.h"
namespace shaka {
namespace media {
/// Encrypted media init data types. It is extended from:
/// https://www.w3.org/TR/eme-initdata-registry/#registry.
enum class EmeInitDataType {
UNKNOWN,
/// One or multiple PSSH boxes.
CENC,
/// WebM init data is basically KeyId.
WEBM,
/// JSON formatted key ids.
KEYIDS,
/// Widevine classic asset id.
WIDEVINE_CLASSIC,
MAX = WIDEVINE_CLASSIC
};
struct EncryptionKey {
std::vector<ProtectionSystemSpecificInfo> key_system_info;
std::vector<uint8_t> key_id;
std::vector<uint8_t> key;
std::vector<uint8_t> iv;
};
typedef std::map<std::string, std::unique_ptr<EncryptionKey>> EncryptionKeyMap;
/// KeySource is responsible for encryption key acquisition.
class KeySource {
public:
KeySource(ProtectionSystem protection_systems, FourCC protection_scheme);
virtual ~KeySource();
/// Fetch keys based on the specified encrypted media init data.
/// @param init_data_type specifies the encrypted media init data type.
/// @param init_data contains the init data.
/// @return OK on success, an error status otherwise.
virtual Status FetchKeys(EmeInitDataType init_data_type,
const std::vector<uint8_t>& init_data) = 0;
/// Get encryption key of the specified stream label.
/// @param stream_label is the label of stream for which retrieving the key.
/// @param key is a pointer to the EncryptionKey which will hold the retrieved
/// key. Owner retains ownership, and may not be NULL.
/// @return OK on success, an error status otherwise.
virtual Status GetKey(const std::string& stream_label,
EncryptionKey* key) = 0;
/// Get the encryption key specified by the CENC key ID.
/// @param key_id is the unique identifier for the key being retreived.
/// @param key is a pointer to the EncryptionKey which will hold the retrieved
/// key. Owner retains ownership, and may not be NULL.
/// @return OK on success, or an error status otherwise.
virtual Status GetKey(const std::vector<uint8_t>& key_id,
EncryptionKey* key) = 0;
/// Get encryption key of the specified track type at the specified index.
/// @param crypto_period_index is the sequence number of the key rotation
/// period for which the key is being retrieved.
/// @param crypto_period_duration_in_seconds is the duration of the crypto
/// period in seconds.
/// @param stream_label is the label of stream for which retrieving the key.
/// @param key is a pointer to the EncryptionKey which will hold the retrieved
/// key. Owner retains ownership, and may not be NULL.
/// @return OK on success, an error status otherwise.
virtual Status GetCryptoPeriodKey(uint32_t crypto_period_index,
uint32_t crypto_period_duration_in_seconds,
const std::string& stream_label,
EncryptionKey* key) = 0;
protected:
/// Update the protection sysmtem specific info for the encryption keys.
/// @param encryption_key_map is a map of encryption keys for all tracks.
Status UpdateProtectionSystemInfo(EncryptionKeyMap* encryption_key_map);
private:
std::vector<std::unique_ptr<PsshGenerator>> pssh_generators_;
std::vector<std::vector<uint8_t>> no_pssh_systems_;
DISALLOW_COPY_AND_ASSIGN(KeySource);
};
} // namespace media
} // namespace shaka
#endif // PACKAGER_MEDIA_BASE_KEY_SOURCE_H_