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|
/** toxrtp.c
*
* Copyright (C) 2013 Tox project All Rights Reserved.
*
* This file is part of Tox.
*
* Tox is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Tox is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Tox. If not, see <http://www.gnu.org/licenses/>.
*
*
* Report bugs/suggestions to me ( mannol ) at either #tox-dev @ freenode.net:6667 or
* my email: eniz_vukovic@hotmail.com
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif /* HAVE_CONFIG_H */
#include "toxrtp.h"
#include <assert.h>
#include <stdlib.h>
#include "../toxcore/util.h"
#include "../toxcore/network.h"
#include "../toxcore/net_crypto.h"
#include "../toxcore/Messenger.h"
#define PAYLOAD_ID_VALUE_OPUS 1
#define PAYLOAD_ID_VALUE_VP8 2
#define size_32 4
#define inline__ inline __attribute__((always_inline))
#define ADD_FLAG_VERSION(_h, _v) do { ( _h->flags ) &= 0x3F; ( _h->flags ) |= ( ( ( _v ) << 6 ) & 0xC0 ); } while(0)
#define ADD_FLAG_PADDING(_h, _v) do { if ( _v > 0 ) _v = 1; ( _h->flags ) &= 0xDF; ( _h->flags ) |= ( ( ( _v ) << 5 ) & 0x20 ); } while(0)
#define ADD_FLAG_EXTENSION(_h, _v) do { if ( _v > 0 ) _v = 1; ( _h->flags ) &= 0xEF;( _h->flags ) |= ( ( ( _v ) << 4 ) & 0x10 ); } while(0)
#define ADD_FLAG_CSRCC(_h, _v) do { ( _h->flags ) &= 0xF0; ( _h->flags ) |= ( ( _v ) & 0x0F ); } while(0)
#define ADD_SETTING_MARKER(_h, _v) do { if ( _v > 1 ) _v = 1; ( _h->marker_payloadt ) &= 0x7F; ( _h->marker_payloadt ) |= ( ( ( _v ) << 7 ) /*& 0x80 */ ); } while(0)
#define ADD_SETTING_PAYLOAD(_h, _v) do { if ( _v > 127 ) _v = 127; ( _h->marker_payloadt ) &= 0x80; ( _h->marker_payloadt ) |= ( ( _v ) /* & 0x7F */ ); } while(0)
#define GET_FLAG_VERSION(_h) (( _h->flags & 0xd0 ) >> 6)
#define GET_FLAG_PADDING(_h) (( _h->flags & 0x20 ) >> 5)
#define GET_FLAG_EXTENSION(_h) (( _h->flags & 0x10 ) >> 4)
#define GET_FLAG_CSRCC(_h) ( _h->flags & 0x0f )
#define GET_SETTING_MARKER(_h) (( _h->marker_payloadt ) >> 7)
#define GET_SETTING_PAYLOAD(_h) ((_h->marker_payloadt) & 0x7f)
/**
* @brief Converts 4 bytes to uint32_t
*
* @param dest Where to convert
* @param bytes What bytes
* @return void
*/
inline__ void bytes_to_U32(uint32_t* dest, const uint8_t* bytes)
{
*dest =
#ifdef WORDS_BIGENDIAN
( ( uint32_t ) * bytes ) |
( ( uint32_t ) * ( bytes + 1 ) << 8 ) |
( ( uint32_t ) * ( bytes + 2 ) << 16 ) |
( ( uint32_t ) * ( bytes + 3 ) << 24 ) ;
#else
( ( uint32_t ) * bytes << 24 ) |
( ( uint32_t ) * ( bytes + 1 ) << 16 ) |
( ( uint32_t ) * ( bytes + 2 ) << 8 ) |
( ( uint32_t ) * ( bytes + 3 ) ) ;
#endif
}
/**
* @brief Converts 2 bytes to uint16_t
*
* @param dest Where to convert
* @param bytes What bytes
* @return void
*/
inline__ void bytes_to_U16(uint16_t* dest, const uint8_t* bytes)
{
*dest =
#ifdef WORDS_BIGENDIAN
( ( uint16_t ) * bytes ) |
( ( uint16_t ) * ( bytes + 1 ) << 8 );
#else
( ( uint16_t ) * bytes << 8 ) |
( ( uint16_t ) * ( bytes + 1 ) );
#endif
}
/**
* @brief Convert uint32_t to byte string of size 4
*
* @param dest Where to convert
* @param value The value
* @return void
*/
inline__ void U32_to_bytes(uint8_t* dest, uint32_t value)
{
#ifdef WORDS_BIGENDIAN
*(dest) = ( value );
*(dest + 1) = ( value >> 8 );
*(dest + 2) = ( value >> 16 );
*(dest + 3) = ( value >> 24 );
#else
*(dest) = ( value >> 24 );
*(dest + 1) = ( value >> 16 );
*(dest + 2) = ( value >> 8 );
*(dest + 3) = ( value );
#endif
}
/**
* @brief Convert uint16_t to byte string of size 2
*
* @param dest Where to convert
* @param value The value
* @return void
*/
inline__ void U16_to_bytes(uint8_t* dest, uint16_t value)
{
#ifdef WORDS_BIGENDIAN
*(dest) = ( value );
*(dest + 1) = ( value >> 8 );
#else
*(dest) = ( value >> 8 );
*(dest + 1) = ( value );
#endif
}
/**
* @brief Checks if message came in late.
*
* @param session Control session.
* @param msg The message.
* @return int
* @retval -1 The message came in order.
* @retval 0 The message came late.
*/
inline__ int check_late_message (RTPSession* session, RTPMessage* msg)
{
/*
* Check Sequence number. If this new msg has lesser number then the session->rsequnum
* it shows that the message came in late. Also check timestamp to be 100% certain.
*
*/
return ( msg->header->sequnum < session->rsequnum && msg->header->timestamp < session->timestamp ) ? 0 : -1;
}
/**
* @brief Increases nonce value by 'target'
*
* @param nonce The nonce
* @param target The target
* @return void
*/
inline__ void increase_nonce(uint8_t* nonce, uint16_t target)
{
uint16_t _nonce_counter;
uint8_t _reverse_bytes[2];
_reverse_bytes[0] = nonce[crypto_box_NONCEBYTES - 1];
_reverse_bytes[1] = nonce[crypto_box_NONCEBYTES - 2];
bytes_to_U16(&_nonce_counter, _reverse_bytes );
/* Check overflow */
if (_nonce_counter > UINT16_MAX - target ) { /* 2 bytes are not long enough */
uint8_t _it = 3;
while ( _it <= crypto_box_NONCEBYTES ) _it += ++nonce[crypto_box_NONCEBYTES - _it] ? crypto_box_NONCEBYTES : 1;
_nonce_counter = _nonce_counter - (UINT16_MAX - target ); /* Assign the rest of it */
} else { /* Increase nonce */
_nonce_counter+= target;
}
/* Assign the last bytes */
U16_to_bytes( _reverse_bytes, _nonce_counter);
nonce [crypto_box_NONCEBYTES - 1] = _reverse_bytes[0];
nonce [crypto_box_NONCEBYTES - 2] = _reverse_bytes[1];
}
/**
* @brief Speaks for it self.
*
*/
static const uint32_t payload_table[] =
{
8000, 8000, 8000, 8000, 8000, 8000, 16000, 8000, 8000, 8000, /* 0-9 */
44100, 44100, 0, 0, 90000, 8000, 11025, 22050, 0, 0, /* 10-19 */
0, 0, 0, 0, 0, 90000, 90000, 0, 90000, 0, /* 20-29 */
0, 90000, 90000, 90000, 90000, 0, 0, 0, 0, 0, /* 30-39 */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 40-49 */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 50-59 */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 60-69 */
PAYLOAD_ID_VALUE_OPUS, PAYLOAD_ID_VALUE_VP8, 0, 0, 0, 0, 0, 0, 0, 0,/* 70-79 */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 80-89 */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 90-99 */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 100-109 */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 110-119 */
0, 0, 0, 0, 0, 0, 0, 0 /* 120-127 */
};
/**
* @brief Extracts header from payload.
*
* @param payload The payload.
* @param length The size of payload.
* @return RTPHeader* Extracted header.
* @retval NULL Error occurred while extracting header.
*/
RTPHeader* extract_header ( const uint8_t* payload, int length )
{
if ( !payload || !length ) {
return NULL;
}
const uint8_t* _it = payload;
RTPHeader* _retu = calloc(1, sizeof (RTPHeader));
assert(_retu);
_retu->flags = *_it; ++_it;
/* This indicates if the first 2 bytes are valid.
* Now it my happen that this is out of order but
* it cuts down chances of parsing some invalid value
*/
if ( GET_FLAG_VERSION(_retu) != RTP_VERSION ){
/* Deallocate */
free(_retu);
return NULL;
}
/*
* Added a check for the size of the header little sooner so
* I don't need to parse the other stuff if it's bad
*/
uint8_t _cc = GET_FLAG_CSRCC ( _retu );
uint32_t _length = 12 /* Minimum header len */ + ( _cc * 4 );
if ( length < _length ) {
/* Deallocate */
free(_retu);
return NULL;
}
if ( _cc > 0 ) {
_retu->csrc = calloc (_cc, sizeof (uint32_t));
assert(_retu->csrc);
} else { /* But this should not happen ever */
/* Deallocate */
free(_retu);
return NULL;
}
_retu->marker_payloadt = *_it; ++_it;
_retu->length = _length;
bytes_to_U32(&_retu->timestamp, _it); _it += 4;
bytes_to_U32(&_retu->ssrc, _it);
uint8_t _x;
for ( _x = 0; _x < _cc; _x++ ) {
_it += 4; bytes_to_U32(&(_retu->csrc[_x]), _it);
}
return _retu;
}
/**
* @brief Extracts external header from payload. Must be called AFTER extract_header()!
*
* @param payload The ITERATED payload.
* @param length The size of payload.
* @return RTPExtHeader* Extracted extension header.
* @retval NULL Error occurred while extracting extension header.
*/
RTPExtHeader* extract_ext_header ( const uint8_t* payload, size_t length )
{
const uint8_t* _it = payload;
RTPExtHeader* _retu = calloc(1, sizeof (RTPExtHeader));
assert(_retu);
uint16_t _ext_length;
bytes_to_U16(&_ext_length, _it); _it += 2;
if ( length < ( _ext_length * sizeof(uint32_t) ) ) {
return NULL;
}
_retu->length = _ext_length;
bytes_to_U16(&_retu->type, _it); _it += 2;
_retu->table = calloc(_ext_length, sizeof (uint32_t));
assert(_retu->table);
uint16_t _x;
for ( _x = 0; _x < _ext_length; _x++ ) {
_it += 4; bytes_to_U32(&(_retu->table[_x]), _it);
}
return _retu;
}
/**
* @brief Adds header to payload. Make sure _payload_ has enough space.
*
* @param header The header.
* @param payload The payload.
* @return uint8_t* Iterated position.
*/
uint8_t* add_header ( RTPHeader* header, uint8_t* payload )
{
uint8_t _cc = GET_FLAG_CSRCC ( header );
uint8_t* _it = payload;
/* Add sequence number first */
U16_to_bytes(_it, header->sequnum); _it += 2;
*_it = header->flags; ++_it;
*_it = header->marker_payloadt; ++_it;
U32_to_bytes( _it, header->timestamp); _it+=4;
U32_to_bytes( _it, header->ssrc);
uint8_t _x;
for ( _x = 0; _x < _cc; _x++ ) {
_it+=4; U32_to_bytes( _it, header->csrc[_x]);
}
return _it;
}
/**
* @brief Adds extension header to payload. Make sure _payload_ has enough space.
*
* @param header The header.
* @param payload The payload.
* @return uint8_t* Iterated position.
*/
uint8_t* add_ext_header ( RTPExtHeader* header, uint8_t* payload )
{
uint8_t* _it = payload;
U16_to_bytes(_it, header->length); _it+=2;
U16_to_bytes(_it, header->type); _it-=2; /* Return to 0 position */
uint16_t _x;
for ( _x = 0; _x < header->length; _x++ ) {
_it+=4; U32_to_bytes(_it, header->table[_x]);
}
return _it;
}
/**
* @brief Builds header from control session values.
*
* @param session Control session.
* @return RTPHeader* Created header.
*/
RTPHeader* build_header ( RTPSession* session )
{
RTPHeader* _retu = calloc ( 1, sizeof (RTPHeader) );
assert(_retu);
ADD_FLAG_VERSION ( _retu, session->version );
ADD_FLAG_PADDING ( _retu, session->padding );
ADD_FLAG_EXTENSION ( _retu, session->extension );
ADD_FLAG_CSRCC ( _retu, session->cc );
ADD_SETTING_MARKER ( _retu, session->marker );
ADD_SETTING_PAYLOAD ( _retu, session->payload_type );
_retu->sequnum = session->sequnum;
_retu->timestamp = ((uint32_t)(current_time() / 1000)); /* micro to milli */
_retu->ssrc = session->ssrc;
if ( session->cc > 0 ) {
_retu->csrc = calloc(session->cc, sizeof (uint32_t));
assert(_retu->csrc);
int i;
for ( i = 0; i < session->cc; i++ ) {
_retu->csrc[i] = session->csrc[i];
}
} else {
_retu->csrc = NULL;
}
_retu->length = 12 /* Minimum header len */ + ( session->cc * size_32 );
return _retu;
}
/**
* @brief Parses data into RTPMessage struct. Stores headers separately from the payload data
* and so the length variable is set accordingly. _sequnum_ argument is
* passed by the handle_packet() since it's parsed already.
*
* @param session Control session.
* @param sequnum Sequence number that's parsed from payload in handle_packet()
* @param data Payload data.
* @param length Payload size.
* @return RTPMessage*
* @retval NULL Error occurred.
*/
RTPMessage* msg_parse ( uint16_t sequnum, const uint8_t* data, int length )
{
RTPMessage* _retu = calloc(1, sizeof (RTPMessage));
_retu->header = extract_header ( data, length ); /* It allocates memory and all */
if ( !_retu->header ){
free(_retu);
return NULL;
}
_retu->header->sequnum = sequnum;
_retu->length = length - _retu->header->length;
uint16_t _from_pos = _retu->header->length - 2 /* Since sequ num is excluded */ ;
if ( GET_FLAG_EXTENSION ( _retu->header ) ) {
_retu->ext_header = extract_ext_header ( data + _from_pos, length );
if ( _retu->ext_header ){
_retu->length -= ( 4 /* Minimum ext header len */ + _retu->ext_header->length * size_32 );
_from_pos += ( 4 /* Minimum ext header len */ + _retu->ext_header->length * size_32 );
} else { /* Error */
free (_retu->ext_header);
free (_retu->header);
free (_retu);
return NULL;
}
} else {
_retu->ext_header = NULL;
}
memcpy ( _retu->data, data + _from_pos, length - _from_pos );
_retu->next = NULL;
return _retu;
}
/**
* @brief Callback for networking core.
*
* @param object RTPSession object.
* @param ip_port Where the message comes from.
* @param data Message data.
* @param length Message length.
* @return int
* @retval -1 Error occurred.
* @retval 0 Success.
*/
int rtp_handle_packet ( void* object, IP_Port ip_port, uint8_t* data, uint32_t length )
{
RTPSession* _session = object;
RTPMessage* _msg;
if ( !_session )
return -1;
uint8_t _plain[MAX_UDP_PACKET_SIZE];
uint16_t _sequnum;
bytes_to_U16(&_sequnum, data + 1);
/* Clculate the right nonce */
uint8_t _calculated[crypto_box_NONCEBYTES];
memcpy(_calculated, _session->decrypt_nonce, crypto_box_NONCEBYTES);
increase_nonce ( _calculated, _sequnum );
/* Decrypt message */
int _decrypted_length = decrypt_data_symmetric(
(uint8_t*)_session->decrypt_key, _calculated, data + 3, length - 3, _plain );
/* This packet is either not encrypted properly or late
*/
if ( -1 == _decrypted_length ){
/* If this is the case, then the packet is most likely late.
* Try with old nonce cycle.
*/
if ( _session->rsequnum < _sequnum ) {
_decrypted_length = decrypt_data_symmetric(
(uint8_t*)_session->decrypt_key, _session->nonce_cycle, data + 3, length - 3, _plain );
if ( !_decrypted_length ) return -1; /* This packet is not encrypted properly */
/* Otherwise, if decryption is ok with new cycle, set new cycle
*/
} else {
increase_nonce ( _calculated, MAX_SEQU_NUM );
_decrypted_length = decrypt_data_symmetric(
(uint8_t*)_session->decrypt_key, _calculated, data + 3, length - 3, _plain );
if ( !_decrypted_length ) return -1; /* This is just an error */
/* A new cycle setting. */
memcpy(_session->nonce_cycle, _session->decrypt_nonce, crypto_box_NONCEBYTES);
memcpy(_session->decrypt_nonce, _calculated, crypto_box_NONCEBYTES);
}
}
_msg = msg_parse ( _sequnum, _plain, _decrypted_length );
if ( !_msg ) return -1;
/* Hopefully this goes well
* NOTE: Is this even used?
*/
memcpy(&_msg->from, &ip_port, sizeof(tox_IP_Port));
/* Check if message came in late */
if ( check_late_message(_session, _msg) < 0 ) { /* Not late */
_session->rsequnum = _msg->header->sequnum;
_session->timestamp = _msg->header->timestamp;
}
pthread_mutex_lock(&_session->mutex);
if ( _session->last_msg ) {
_session->last_msg->next = _msg;
_session->last_msg = _msg;
} else {
_session->last_msg = _session->oldest_msg = _msg;
}
pthread_mutex_unlock(&_session->mutex);
return 0;
}
/**
* @brief Stores headers and payload data in one container ( data )
* and the length is set accordingly. Returned message is used for sending _only_.
*
* @param session The control session.
* @param data Payload data to send ( This is what you pass ).
* @param length Size of the payload data.
* @return RTPMessage* Created message.
* @retval NULL Error occurred.
*/
RTPMessage* rtp_new_message ( RTPSession* session, const uint8_t* data, uint32_t length )
{
if ( !session )
return NULL;
uint8_t* _from_pos;
RTPMessage* _retu = calloc(1, sizeof (RTPMessage));
assert(_retu);
/* Sets header values and copies the extension header in _retu */
_retu->header = build_header ( session ); /* It allocates memory and all */
_retu->ext_header = session->ext_header;
uint32_t _total_length = length + _retu->header->length;
if ( _retu->ext_header ) {
_total_length += ( 4 /* Minimum ext header len */ + _retu->ext_header->length * size_32 );
_from_pos = add_header ( _retu->header, _retu->data );
_from_pos = add_ext_header ( _retu->ext_header, _from_pos + 1 );
} else {
_from_pos = add_header ( _retu->header, _retu->data );
}
/*
* Parses the extension header into the message
* Of course if any
*/
/* Appends _data on to _retu->_data */
memcpy ( _from_pos + 1, data, length );
_retu->length = _total_length;
_retu->next = NULL;
return _retu;
}
/********************************************************************************************************************
********************************************************************************************************************
********************************************************************************************************************
********************************************************************************************************************
********************************************************************************************************************
*
*
*
* PUBLIC API FUNCTIONS IMPLEMENTATIONS
*
*
*
********************************************************************************************************************
********************************************************************************************************************
********************************************************************************************************************
********************************************************************************************************************
********************************************************************************************************************/
/**
* @brief Release all messages held by session.
*
* @param session The session.
* @return int
* @retval -1 Error occurred.
* @retval 0 Success.
*/
int rtp_release_session_recv ( RTPSession* session )
{
if ( !session ){
return -1;
}
RTPMessage* _tmp,* _it;
pthread_mutex_lock(&session->mutex);
for ( _it = session->oldest_msg; _it; _it = _tmp ){
_tmp = _it->next;
rtp_free_msg( session, _it);
}
session->last_msg = session->oldest_msg = NULL;
pthread_mutex_unlock(&session->mutex);
return 0;
}
/**
* @brief Get's oldes message in the list.
*
* @param session Where the list is.
* @return RTPMessage* The message. You _must_ call rtp_msg_free() to free it.
* @retval NULL No messages in the list, or no list.
*/
RTPMessage* rtp_recv_msg ( RTPSession* session )
{
if ( !session )
return NULL;
RTPMessage* _retu = session->oldest_msg;
pthread_mutex_lock(&session->mutex);
if ( _retu )
session->oldest_msg = _retu->next;
if ( !session->oldest_msg )
session->last_msg = NULL;
pthread_mutex_unlock(&session->mutex);
return _retu;
}
/**
* @brief Sends data to _RTPSession::dest
*
* @param session The session.
* @param messenger Tox* object.
* @param data The payload.
* @param length Size of the payload.
* @return int
* @retval -1 On error.
* @retval 0 On success.
*/
int rtp_send_msg ( RTPSession* session, Tox* messenger, const uint8_t* data, uint16_t length )
{
RTPMessage* msg = rtp_new_message (session, data, length);
if ( !msg ) return -1;
uint8_t _send_data [ MAX_UDP_PACKET_SIZE ];
_send_data[0] = session->prefix;
/* Generate the right nonce */
uint8_t _calculated[crypto_box_NONCEBYTES];
memcpy(_calculated, session->encrypt_nonce, crypto_box_NONCEBYTES);
increase_nonce ( _calculated, msg->header->sequnum );
/* Need to skip 2 bytes that are for sequnum */
int encrypted_length = encrypt_data_symmetric(
(uint8_t*) session->encrypt_key, _calculated, msg->data + 2, msg->length - 2, _send_data + 3 );
int full_length = encrypted_length + 3;
_send_data[1] = msg->data[0];
_send_data[2] = msg->data[1];
if ( full_length != sendpacket ( ((Messenger*)messenger)->net, *((IP_Port*) &session->dest), _send_data, full_length) ) {
printf("Rtp error: %s\n", strerror(errno));
return -1;
}
/* Set sequ number */
if ( session->sequnum >= MAX_SEQU_NUM ) {
session->sequnum = 0;
memcpy(session->encrypt_nonce, _calculated, crypto_box_NONCEBYTES);
} else {
session->sequnum++;
}
rtp_free_msg ( session, msg );
return 0;
}
/**
* @brief Speaks for it self.
*
* @param session The control session msg belongs to. You set it as NULL when freeing recved messages.
* Otherwise set it to session the message was created from.
* @param msg The message.
* @return void
*/
void rtp_free_msg ( RTPSession* session, RTPMessage* msg )
{
if ( !session ){
free ( msg->header->csrc );
if ( msg->ext_header ){
free ( msg->ext_header->table );
free ( msg->ext_header );
}
} else {
if ( session->csrc != msg->header->csrc )
free ( msg->header->csrc );
if ( msg->ext_header && session->ext_header != msg->ext_header ) {
free ( msg->ext_header->table );
free ( msg->ext_header );
}
}
free ( msg->header );
free ( msg );
}
/**
* @brief Must be called before calling any other rtp function. It's used
* to initialize RTP control session.
*
* @param payload_type Type of payload used to send. You can use values in toxmsi.h::MSICallType
* @param messenger Tox* object.
* @param friend_num Friend id.
* @param encrypt_key Speaks for it self.
* @param decrypt_key Speaks for it self.
* @param encrypt_nonce Speaks for it self.
* @param decrypt_nonce Speaks for it self.
* @return RTPSession* Created control session.
* @retval NULL Error occurred.
*/
RTPSession* rtp_init_session ( int payload_type,
Tox* messenger,
int friend_num,
const uint8_t* encrypt_key,
const uint8_t* decrypt_key,
const uint8_t* encrypt_nonce,
const uint8_t* decrypt_nonce
)
{
Messenger* _messenger_casted = (Messenger*) messenger;
IP_Port _dest = get_friend_ipport(_messenger_casted, friend_num );
/* This should be enough eh? */
if ( _dest.port == 0) {
return NULL;
}
RTPSession* _retu = calloc(1, sizeof(RTPSession));
assert(_retu);
networking_registerhandler(_messenger_casted->net, payload_type, rtp_handle_packet, _retu);
_retu->version = RTP_VERSION; /* It's always 2 */
_retu->padding = 0; /* If some additional data is needed about the packet */
_retu->extension = 0; /* If extension to header is needed */
_retu->cc = 1; /* Amount of contributors */
_retu->csrc = NULL; /* Container */
_retu->ssrc = randombytes_random();
_retu->marker = 0;
_retu->payload_type = payload_table[payload_type];
_retu->dest = *((tox_IP_Port*)&_dest);
_retu->rsequnum = _retu->sequnum = 1;
_retu->ext_header = NULL; /* When needed allocate */
_retu->framerate = -1;
_retu->resolution = -1;
_retu->encrypt_key = encrypt_key;
_retu->decrypt_key = decrypt_key;
/* Need to allocate new memory */
_retu->encrypt_nonce = calloc ( crypto_box_NONCEBYTES, sizeof (uint8_t) ); assert(_retu->encrypt_nonce);
_retu->decrypt_nonce = calloc ( crypto_box_NONCEBYTES, sizeof (uint8_t) ); assert(_retu->decrypt_nonce);
_retu->nonce_cycle = calloc ( crypto_box_NONCEBYTES, sizeof (uint8_t) ); assert(_retu->nonce_cycle);
memcpy(_retu->encrypt_nonce, encrypt_nonce, crypto_box_NONCEBYTES);
memcpy(_retu->decrypt_nonce, decrypt_nonce, crypto_box_NONCEBYTES);
memcpy(_retu->nonce_cycle , decrypt_nonce, crypto_box_NONCEBYTES);
_retu->csrc = calloc(1, sizeof (uint32_t));
assert(_retu->csrc);
_retu->csrc[0] = _retu->ssrc; /* Set my ssrc to the list receive */
/* Also set payload type as prefix */
_retu->prefix = payload_type;
_retu->oldest_msg = _retu->last_msg = NULL;
pthread_mutex_init(&_retu->mutex, NULL);
/*
*
*/
return _retu;
}
/**
* @brief Terminate the session.
*
* @param session The session.
* @param messenger The messenger who owns the session
* @return int
* @retval -1 Error occurred.
* @retval 0 Success.
*/
int rtp_terminate_session ( RTPSession* session, Tox* messenger )
{
if ( !session )
return -1;
networking_registerhandler(((Messenger*)messenger)->net, session->prefix, NULL, NULL);
free ( session->ext_header );
free ( session->csrc );
free ( session->decrypt_nonce );
free ( session->encrypt_nonce );
free ( session->nonce_cycle );
pthread_mutex_destroy(&session->mutex);
/* And finally free session */
free ( session );
return 0;
}
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