gecko-dev/media/mtransport/SrtpFlow.h

70 строки
2.1 KiB
C++

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
// Original author: ekr@rtfm.com
#ifndef srtpflow_h__
#define srtpflow_h__
#include "mozilla/RefPtr.h"
#include "nsISupportsImpl.h"
#include "srtp.h"
namespace mozilla {
#define SRTP_ICM_MASTER_KEY_LENGTH 16
#define SRTP_ICM_MASTER_SALT_LENGTH 14
#define SRTP_ICM_MAX_MASTER_LENGTH \
(SRTP_ICM_MASTER_KEY_LENGTH + SRTP_ICM_MASTER_SALT_LENGTH)
#define SRTP_GCM_MASTER_KEY_MIN_LENGTH 16
#define SRTP_GCM_MASTER_KEY_MAX_LENGTH 32
#define SRTP_GCM_MASTER_SALT_LENGTH 12
#define SRTP_GCM_MIN_MASTER_LENGTH \
(SRTP_GCM_MASTER_KEY_MIN_LENGTH + SRTP_GCM_MASTER_SALT_LENGTH)
#define SRTP_GCM_MAX_MASTER_LENGTH \
(SRTP_GCM_MASTER_KEY_MAX_LENGTH + SRTP_GCM_MASTER_SALT_LENGTH)
#define SRTP_MIN_KEY_LENGTH SRTP_GCM_MIN_MASTER_LENGTH
#define SRTP_MAX_KEY_LENGTH SRTP_GCM_MAX_MASTER_LENGTH
// SRTCP requires an auth tag *plus* a 4-byte index-plus-'E'-bit value (see
// RFC 3711)
#define SRTP_MAX_EXPANSION (SRTP_MAX_TRAILER_LEN + 4)
class SrtpFlow {
~SrtpFlow();
public:
static unsigned int KeySize(int cipher_suite);
static unsigned int SaltSize(int cipher_suite);
static RefPtr<SrtpFlow> Create(int cipher_suite, bool inbound,
const void* key, size_t key_len);
nsresult ProtectRtp(void* in, int in_len, int max_len, int* out_len);
nsresult UnprotectRtp(void* in, int in_len, int max_len, int* out_len);
nsresult ProtectRtcp(void* in, int in_len, int max_len, int* out_len);
nsresult UnprotectRtcp(void* in, int in_len, int max_len, int* out_len);
NS_INLINE_DECL_THREADSAFE_REFCOUNTING(SrtpFlow)
static void srtp_event_handler(srtp_event_data_t* data);
private:
SrtpFlow() : session_(nullptr) {}
nsresult CheckInputs(bool protect, void* in, int in_len, int max_len,
int* out_len);
static nsresult Init();
static bool initialized; // Was libsrtp initialized? Only happens once.
srtp_t session_;
};
} // namespace mozilla
#endif