toxcore/toxav/msi.c
irungentoo 9c6a8432ce Crypto related cleanups.
Moved Bunch of functions from net_crypto to crypto_core.

decrypt_data_fast and decrypt_data_symmetric were the same thing
therefore, removed decrypt_data_fast.

Replaced all the crypto_secretbox_* defines with the equivalent
crypto_box_* one.

New define: crypto_box_KEYBYTES that is equal to
crypto_box_BEFORENMBYTES.
2014-04-21 16:51:36 -04:00

1488 lines
39 KiB
C
Executable File

/** toxmsi.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 at #tox-dev @ freenode.net:6667
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif /* HAVE_CONFIG_H */
#define _BSD_SOURCE
#include "msi.h"
#include "event.h"
#include <assert.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#define inline__ inline __attribute__((always_inline))
#define same(x, y) strcmp((const char*) x, (const char*) y) == 0
#define MSI_MAXMSG_SIZE 1024
#define TYPE_REQUEST 1
#define TYPE_RESPONSE 2
unsigned char *VERSION_STRING = (unsigned char *)"0.3.1";
#define VERSION_STRLEN 5
#define CT_AUDIO_HEADER_VALUE "AUDIO"
#define CT_VIDEO_HEADER_VALUE "VIDEO"
/* Define default timeout for a request.
* There is no behavior specified by the msi on what will
* client do on timeout, but to call timeout callback.
*/
#define m_deftout 10000 /* in milliseconds */
/**
* Protocol:
*
* | desc. ( 1 byte ) | length ( 2 bytes ) | value ( length bytes ) |
*
* ie.
*
* | 0x1 | 0x0 0x7 | "version"
*
* Means: it's field value with length of 7 bytes and value of "version"
* It's similar to amp protocol
*/
#define GENERIC_HEADER(header) \
typedef struct _MSIHeader##header { \
uint8_t* header_value; \
uint16_t size; \
} MSIHeader##header;
GENERIC_HEADER ( Version )
GENERIC_HEADER ( Request )
GENERIC_HEADER ( Response )
GENERIC_HEADER ( CallType )
GENERIC_HEADER ( CallId )
GENERIC_HEADER ( Info )
GENERIC_HEADER ( Reason )
GENERIC_HEADER ( CryptoKey )
GENERIC_HEADER ( Nonce )
/**
* @brief This is the message structure. It contains all of the headers and
* destination/source of the message stored in friend_id.
*
*/
typedef struct _MSIMessage {
MSIHeaderVersion version;
MSIHeaderRequest request;
MSIHeaderResponse response;
MSIHeaderCallType calltype;
MSIHeaderInfo info;
MSIHeaderReason reason;
MSIHeaderCallId callid;
MSIHeaderCryptoKey cryptokey;
MSIHeaderNonce nonce;
struct _MSIMessage *next;
int friend_id;
} MSIMessage;
static struct _Callbacks {
MSICallback function;
void* data;
} callbacks[11] = {0};
inline__ void invoke_callback(MSICallbackID id)
{
/*if ( callbacks[id].function ) event.rise ( callbacks[id].function, callbacks[id].data );*/
if ( callbacks[id].function ) callbacks[id].function ( callbacks[id].data );
}
/*static MSICallback callbacks[10] = {0};*/
/* define strings for the identifiers */
#define VERSION_FIELD "Version"
#define REQUEST_FIELD "Request"
#define RESPONSE_FIELD "Response"
#define INFO_FIELD "INFO"
#define REASON_FIELD "Reason"
#define CALLTYPE_FIELD "Call-type"
#define CALLID_FIELD "Call-id"
#define CRYPTOKEY_FIELD "Crypto-key"
#define NONCE_FIELD "Nonce"
/* protocol descriptors */
#define end_byte 0x0
#define field_byte 0x1
#define value_byte 0x2
typedef enum {
invite,
start,
cancel,
reject,
end,
} MSIRequest;
/**
* @brief Get string value for request.
*
* @param request The request.
* @return const uint8_t* The string
*/
static inline__ const uint8_t *stringify_request ( MSIRequest request )
{
static const uint8_t *strings[] = {
( uint8_t * ) "INVITE",
( uint8_t * ) "START",
( uint8_t * ) "CANCEL",
( uint8_t * ) "REJECT",
( uint8_t * ) "END"
};
return strings[request];
}
typedef enum {
ringing,
starting,
ending,
error
} MSIResponse;
/**
* @brief Get string value for response.
*
* @param response The response.
* @return const uint8_t* The string
*/
static inline__ const uint8_t *stringify_response ( MSIResponse response )
{
static const uint8_t *strings[] = {
( uint8_t * ) "ringing",
( uint8_t * ) "starting",
( uint8_t * ) "ending",
( uint8_t * ) "error"
};
return strings[response];
}
#define ON_HEADER(iterator, header, descriptor, size_const) \
( memcmp(iterator, descriptor, size_const) == 0){ /* Okay */ \
iterator += size_const; /* Set iterator at begining of value part */ \
if ( *iterator != value_byte ) { assert(0); return -1; }\
iterator ++;\
uint16_t _value_size = (uint16_t) *(iterator ) << 8 | \
(uint16_t) *(iterator + 1); \
header.header_value = calloc(sizeof(uint8_t), _value_size); \
header.size = _value_size; \
memcpy(header.header_value, iterator + 2, _value_size);\
iterator = iterator + 2 + _value_size; /* set iterator at new header or end_byte */ \
}
/**
* @brief Parse raw 'data' received from socket into MSIMessage struct.
* Every message has to have end value of 'end_byte' or _undefined_ behavior
* occures. The best practice is to check the end of the message at the handle_packet.
*
* @param msg Container.
* @param data The data.
* @return int
* @retval -1 Error occured.
* @retval 0 Success.
*/
int parse_raw_data ( MSIMessage *msg, const uint8_t *data, uint16_t length )
{
assert ( msg );
if ( data[length - 1] ) /* End byte must have value 0 */
return -1;
const uint8_t *_it = data;
while ( *_it ) {/* until end_byte is hit */
uint16_t itedlen = (_it - data) + 2;
if ( *_it == field_byte && itedlen < length ) {
uint16_t _size = ( uint16_t ) * ( _it + 1 ) << 8 |
( uint16_t ) * ( _it + 2 );
if ( itedlen + _size > length ) return -1;
_it += 3; /* place it at the field value beginning */
switch ( _size ) { /* Compare the size of the hardcoded values ( vary fast and convenient ) */
case 4: { /* INFO header */
if ON_HEADER ( _it, msg->info, INFO_FIELD, 4 )
}
break;
case 5: { /* NONCE header */
if ON_HEADER ( _it, msg->nonce, NONCE_FIELD, 5 )
}
break;
case 6: { /* Reason header */
if ON_HEADER ( _it, msg->reason, REASON_FIELD, 6 )
}
break;
case 7: { /* Version, Request, Call-id headers */
if ON_HEADER ( _it, msg->version, VERSION_FIELD, 7 )
else if ON_HEADER ( _it, msg->request, REQUEST_FIELD, 7 )
else if ON_HEADER ( _it, msg->callid, CALLID_FIELD, 7 )
}
break;
case 8: { /* Response header */
if ON_HEADER ( _it, msg->response, RESPONSE_FIELD, 8 )
}
break;
case 9: { /* Call-type header */
if ON_HEADER ( _it, msg->calltype, CALLTYPE_FIELD, 9 )
}
break;
case 10: { /* Crypto-key headers */
if ON_HEADER ( _it, msg->cryptokey, CRYPTOKEY_FIELD, 10 )
}
break;
default:
return -1;
}
} else return -1;
/* If it's anything else return failure as the message is invalid */
}
return 0;
}
#define ALLOCATE_HEADER( var, mheader_value, t_size) \
var.header_value = calloc(sizeof *mheader_value, t_size); \
memcpy(var.header_value, mheader_value, t_size); \
var.size = t_size;
/**
* @brief Speaks for it self.
*
* @param msg The message.
* @return void
*/
void free_message ( MSIMessage *msg )
{
assert ( msg );
free ( msg->calltype.header_value );
free ( msg->request.header_value );
free ( msg->response.header_value );
free ( msg->version.header_value );
free ( msg->info.header_value );
free ( msg->cryptokey.header_value );
free ( msg->nonce.header_value );
free ( msg->reason.header_value );
free ( msg->callid.header_value );
free ( msg );
}
/**
* @brief Create the message.
*
* @param type Request or response.
* @param type_id Type of request/response.
* @return MSIMessage* Created message.
* @retval NULL Error occured.
*/
MSIMessage *msi_new_message ( uint8_t type, const uint8_t *type_id )
{
MSIMessage *_retu = calloc ( sizeof ( MSIMessage ), 1 );
assert ( _retu );
if ( type == TYPE_REQUEST ) {
ALLOCATE_HEADER ( _retu->request, type_id, strlen ( (const char *)type_id ) )
} else if ( type == TYPE_RESPONSE ) {
ALLOCATE_HEADER ( _retu->response, type_id, strlen ( (const char *)type_id ) )
} else {
free_message ( _retu );
return NULL;
}
ALLOCATE_HEADER ( _retu->version, VERSION_STRING, strlen ( (const char *)VERSION_STRING ) )
return _retu;
}
/**
* @brief Parse data from handle_packet.
*
* @param data The data.
* @return MSIMessage* Parsed message.
* @retval NULL Error occured.
*/
MSIMessage *parse_message ( const uint8_t *data, uint16_t length )
{
assert ( data );
MSIMessage *_retu = calloc ( sizeof ( MSIMessage ), 1 );
assert ( _retu );
memset ( _retu, 0, sizeof ( MSIMessage ) );
if ( parse_raw_data ( _retu, data, length ) == -1 ) {
free_message ( _retu );
return NULL;
}
if ( !_retu->version.header_value || VERSION_STRLEN != _retu->version.size ||
memcmp ( _retu->version.header_value, VERSION_STRING, VERSION_STRLEN ) != 0 ) {
free_message ( _retu );
return NULL;
}
return _retu;
}
/**
* @brief Speaks for it self.
*
* @param dest Container.
* @param header_field Field.
* @param header_value Field value.
* @param value_len Length of field value.
* @param length Pointer to container length.
* @return uint8_t* Iterated container.
*/
uint8_t *append_header_to_string (
uint8_t *dest,
const uint8_t *header_field,
const uint8_t *header_value,
uint16_t value_len,
uint16_t *length )
{
assert ( dest );
assert ( header_value );
assert ( header_field );
const uint8_t *_hvit = header_value;
uint16_t _total = 6 + value_len; /* 6 is known plus header value len + field len*/
*dest = field_byte; /* Set the first byte */
uint8_t *_getback_byte = dest + 1; /* remeber the byte we were on */
dest += 3; /* swith to 4th byte where field value starts */
/* Now set the field value and calculate it's length */
uint16_t _i = 0;
for ( ; header_field[_i]; ++_i ) {
*dest = header_field[_i];
++dest;
};
_total += _i;
/* Now set the length of the field byte */
*_getback_byte = ( uint8_t ) _i >> 8;
_getback_byte++;
*_getback_byte = ( uint8_t ) _i;
/* for value part do it regulary */
*dest = value_byte;
dest++;
*dest = ( uint8_t ) value_len >> 8;
dest++;
*dest = ( uint8_t ) value_len;
dest++;
for ( _i = value_len; _i; --_i ) {
*dest = *_hvit;
++_hvit;
++dest;
}
*length += _total;
return dest;
}
#define CLEAN_ASSIGN(added, var, field, header)\
if ( header.header_value ) { var = append_header_to_string(var, (const uint8_t*)field, header.header_value, header.size, &added); }
/**
* @brief Convert MSIMessage struct to _sendable_ string.
*
* @param msg The message.
* @param dest Destination.
* @return uint16_t It's final size.
*/
uint16_t message_to_string ( MSIMessage *msg, uint8_t *dest )
{
assert ( msg );
assert ( dest );
uint8_t *_iterated = dest;
uint16_t _size = 0;
CLEAN_ASSIGN ( _size, _iterated, VERSION_FIELD, msg->version );
CLEAN_ASSIGN ( _size, _iterated, REQUEST_FIELD, msg->request );
CLEAN_ASSIGN ( _size, _iterated, RESPONSE_FIELD, msg->response );
CLEAN_ASSIGN ( _size, _iterated, CALLTYPE_FIELD, msg->calltype );
CLEAN_ASSIGN ( _size, _iterated, INFO_FIELD, msg->info );
CLEAN_ASSIGN ( _size, _iterated, CALLID_FIELD, msg->callid );
CLEAN_ASSIGN ( _size, _iterated, REASON_FIELD, msg->reason );
CLEAN_ASSIGN ( _size, _iterated, CRYPTOKEY_FIELD, msg->cryptokey );
CLEAN_ASSIGN ( _size, _iterated, NONCE_FIELD, msg->nonce );
*_iterated = end_byte;
_size ++;
return _size;
}
#define GENERIC_SETTER_DEFINITION(header) \
void msi_msg_set_##header ( MSIMessage* _msg, const uint8_t* header_value, uint16_t _size ) \
{ assert(_msg); assert(header_value); \
free(_msg->header.header_value); \
ALLOCATE_HEADER( _msg->header, header_value, _size )}
GENERIC_SETTER_DEFINITION ( calltype )
GENERIC_SETTER_DEFINITION ( reason )
GENERIC_SETTER_DEFINITION ( info )
GENERIC_SETTER_DEFINITION ( callid )
GENERIC_SETTER_DEFINITION ( cryptokey )
GENERIC_SETTER_DEFINITION ( nonce )
/**
* @brief Generate _random_ alphanumerical string.
*
* @param str Destination.
* @param size Size of string.
* @return void
*/
void t_randomstr ( uint8_t *str, size_t size )
{
assert ( str );
static const uint8_t _bytes[] =
"0123456789"
"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
"abcdefghijklmnopqrstuvwxyz";
size_t _it = 0;
for ( ; _it < size; _it++ ) {
str[_it] = _bytes[ random_int() % 61 ];
}
}
typedef enum {
error_deadcall = 1, /* has call id but it's from old call */
error_id_mismatch, /* non-existing call */
error_no_callid, /* not having call id */
error_no_call, /* no call in session */
error_no_crypto_key, /* no crypto key */
error_busy
} MSICallError; /* Error codes */
/**
* @brief Stringify error code.
*
* @param error_code The code.
* @return const uint8_t* The string.
*/
static inline__ const uint8_t *stringify_error ( MSICallError error_code )
{
static const uint8_t *strings[] = {
( uint8_t * ) "",
( uint8_t * ) "Using dead call",
( uint8_t * ) "Call id not set to any call",
( uint8_t * ) "Call id not available",
( uint8_t * ) "No active call in session",
( uint8_t * ) "No Crypto-key set",
( uint8_t * ) "Callee busy"
};
return strings[error_code];
}
/**
* @brief Convert error_code into string.
*
* @param error_code The code.
* @return const uint8_t* The string.
*/
static inline__ const uint8_t *stringify_error_code ( MSICallError error_code )
{
static const uint8_t *strings[] = {
( uint8_t * ) "",
( uint8_t * ) "1",
( uint8_t * ) "2",
( uint8_t * ) "3",
( uint8_t * ) "4",
( uint8_t * ) "5",
( uint8_t * ) "6"
};
return strings[error_code];
}
/**
* @brief Speaks for it self.
*
* @param session Control session.
* @param msg The message.
* @param to Where to.
* @return int
* @retval -1 Error occured.
* @retval 0 Success.
*/
int send_message ( MSISession *session, MSIMessage *msg, uint32_t to )
{
msi_msg_set_callid ( msg, session->call->id, CALL_ID_LEN );
uint8_t _msg_string_final [MSI_MAXMSG_SIZE];
uint16_t _length = message_to_string ( msg, _msg_string_final );
return m_msi_packet(session->messenger_handle, to, _msg_string_final, _length) ? 0 : -1;
}
/**
* @brief Determine 'bigger' call id
*
* @param first duh
* @param second duh
* @return int
* @retval 0 it's first
* @retval 1 it's second
*/
int call_id_bigger( const uint8_t* first, const uint8_t* second)
{
int i = 0;
for (; i < CALL_ID_LEN; i ++) {
if ( first[i] != second[i] )
return first[i] > second [i] ? 0 : 1;
}
}
/**
* @brief Speaks for it self.
*
* @param session Control session.
* @param msg The message.
* @param peer_id The peer.
* @return void
*/
void flush_peer_type ( MSISession *session, MSIMessage *msg, int peer_id )
{
if ( msg->calltype.header_value ) {
uint8_t hdrval [MSI_MAXMSG_SIZE]; /* Make sure no overflow */
memcpy(hdrval, msg->calltype.header_value, msg->calltype.size);
hdrval[msg->calltype.size] = '\0';
if ( strcmp ( ( const char * ) hdrval, CT_AUDIO_HEADER_VALUE ) == 0 ) {
session->call->type_peer[peer_id] = type_audio;
} else if ( strcmp ( ( const char * ) hdrval, CT_VIDEO_HEADER_VALUE ) == 0 ) {
session->call->type_peer[peer_id] = type_video;
} else {} /* Error */
} else {} /* Error */
}
void handle_remote_connection_change(Messenger *messenger, int friend_num, uint8_t status, void *session_p)
{
MSISession *session = session_p;
switch ( status ) {
case 0: { /* Went offline */
if ( session->call ) {
int i = 0;
for ( ; i < session->call->peer_count; i ++ )
if ( session->call->peers[i] == friend_num ) {
invoke_callback(MSI_OnPeerTimeout);
return;
}
}
}
break;
default:
break;
}
}
/**
* @brief Sends error response to peer.
*
* @param session The session.
* @param errid The id.
* @param to Where to?
* @return int
* @retval 0 It's always success.
*/
int handle_error ( MSISession *session, MSICallError errid, uint32_t to )
{
MSIMessage *_msg_error = msi_new_message ( TYPE_RESPONSE, stringify_response ( error ) );
const uint8_t *_error_code_str = stringify_error_code ( errid );
msi_msg_set_reason ( _msg_error, _error_code_str, strlen ( ( const char * ) _error_code_str ) );
send_message ( session, _msg_error, to );
free_message ( _msg_error );
session->last_error_id = errid;
session->last_error_str = stringify_error ( errid );
invoke_callback(MSI_OnError);
return 0;
}
/**
* @brief Determine the error if any.
*
* @param session Control session.
* @param msg The message.
* @return int
* @retval -1 No error.
* @retval 0 Error occured and response sent.
*/
int has_call_error ( MSISession *session, MSIMessage *msg )
{
if ( !msg->callid.header_value ) {
return handle_error ( session, error_no_callid, msg->friend_id );
} else if ( !session->call ) {
return handle_error ( session, error_no_call, msg->friend_id );
} else if ( memcmp ( session->call->id, msg->callid.header_value, CALL_ID_LEN ) != 0 ) {
return handle_error ( session, error_id_mismatch, msg->friend_id );
}
return -1;
}
/**
* @brief Function called at request timeout.
*
* @param arg Control session
* @return void*
*/
void *handle_timeout ( void *arg )
{
/* TODO: Cancel might not arrive there; set up
* timers on these cancels and terminate call on
* their timeout
*/
MSISession *_session = arg;
invoke_callback(MSI_OnRequestTimeout);
if ( _session && _session->call ) {
/* TODO: Cancel all? */
/* uint16_t _it = 0;
for ( ; _it < _session->call->peer_count; _it++ ) */
msi_cancel ( _session, _session->call->peers [0], "Request timedout" );
}
pthread_exit(NULL);
}
/**
* @brief Add peer to peer list.
*
* @param call What call.
* @param peer_id Its id.
* @return void
*/
void add_peer( MSICall *call, int peer_id )
{
if ( !call->peers ) {
call->peers = calloc(sizeof(int), 1);
call->peer_count = 1;
} else {
call->peer_count ++;
call->peers = realloc( call->peers, sizeof(int) * call->peer_count);
}
call->peers[call->peer_count - 1] = peer_id;
}
/**
* @brief Speaks for it self.
*
* @param session Control session.
* @param peers Amount of peers. (Currently it only supports 1)
* @param ringing_timeout Ringing timeout.
* @return MSICall* The created call.
*/
MSICall *init_call ( MSISession *session, int peers, int ringing_timeout )
{
assert ( session );
assert ( peers );
MSICall *_call = calloc ( sizeof ( MSICall ), 1 );
_call->type_peer = calloc ( sizeof ( MSICallType ), peers );
assert ( _call );
assert ( _call->type_peer );
/*_call->_participant_count = _peers;*/
_call->request_timer_id = 0;
_call->ringing_timer_id = 0;
_call->key_local = NULL;
_call->key_peer = NULL;
_call->nonce_local = NULL;
_call->nonce_peer = NULL;
_call->ringing_tout_ms = ringing_timeout;
pthread_mutex_init ( &_call->mutex, NULL );
return _call;
}
/**
* @brief Terminate the call.
*
* @param session Control session.
* @return int
* @retval -1 Error occured.
* @retval 0 Success.
*/
int terminate_call ( MSISession *session )
{
assert ( session );
if ( !session->call )
return -1;
/* Check event loop and cancel timed events if there are any
* NOTE: This has to be done before possibly
* locking the mutex the second time
*/
event.timer_release ( session->call->request_timer_id );
event.timer_release ( session->call->ringing_timer_id );
/* Get a handle */
pthread_mutex_lock ( &session->call->mutex );
MSICall *_call = session->call;
session->call = NULL;
free ( _call->type_peer );
free ( _call->key_local );
free ( _call->key_peer );
free ( _call->peers);
/* Release handle */
pthread_mutex_unlock ( &_call->mutex );
pthread_mutex_destroy ( &_call->mutex );
free ( _call );
return 0;
}
/********** Request handlers **********/
int handle_recv_invite ( MSISession *session, MSIMessage *msg )
{
assert ( session );
if ( session->call ) {
if ( session->call->peers[0] == msg->friend_id ) {
/* The glare case. A calls B when at the same time
* B calls A. Who has advantage is set bey calculating
* 'bigger' Call id and then that call id is being used in
* future. User with 'bigger' Call id has the advantage
* as in he will wait the reponse from the other.
*/
if ( call_id_bigger (session->call->id, msg->callid.header_value) == 1 ) { /* Peer has advantage */
terminate_call(session);
}
else {
return 0; /* Wait for ringing from peer */
}
}
else {
handle_error ( session, error_busy, msg->friend_id );
return 0;
}
}
if ( !msg->callid.header_value ) {
handle_error ( session, error_no_callid, msg->friend_id );
return 0;
}
session->call = init_call ( session, 1, 0 );
memcpy ( session->call->id, msg->callid.header_value, CALL_ID_LEN );
session->call->state = call_starting;
add_peer( session->call, msg->friend_id);
flush_peer_type ( session, msg, 0 );
MSIMessage *_msg_ringing = msi_new_message ( TYPE_RESPONSE, stringify_response ( ringing ) );
send_message ( session, _msg_ringing, msg->friend_id );
free_message ( _msg_ringing );
invoke_callback(MSI_OnInvite);
return 1;
}
int handle_recv_start ( MSISession *session, MSIMessage *msg )
{
assert ( session );
if ( has_call_error ( session, msg ) == 0 )
return 0;
if ( !msg->cryptokey.header_value )
return handle_error ( session, error_no_crypto_key, msg->friend_id );
session->call->state = call_active;
session->call->key_peer = calloc ( sizeof ( uint8_t ), crypto_box_KEYBYTES );
memcpy ( session->call->key_peer, msg->cryptokey.header_value, crypto_box_KEYBYTES );
session->call->nonce_peer = calloc ( sizeof ( uint8_t ), crypto_box_NONCEBYTES );
memcpy ( session->call->nonce_peer, msg->nonce.header_value, crypto_box_NONCEBYTES );
flush_peer_type ( session, msg, 0 );
invoke_callback(MSI_OnStart);
return 1;
}
int handle_recv_reject ( MSISession *session, MSIMessage *msg )
{
assert ( session );
if ( has_call_error ( session, msg ) == 0 )
return 0;
MSIMessage *_msg_ending = msi_new_message ( TYPE_RESPONSE, stringify_response ( ending ) );
send_message ( session, _msg_ending, msg->friend_id );
free_message ( _msg_ending );
invoke_callback(MSI_OnReject);
/*
event.timer_release ( session->call->request_timer_id );
session->call->request_timer_id = event.timer_alloc ( handle_timeout, session, m_deftout );
*/
terminate_call(session);
return 1;
}
int handle_recv_cancel ( MSISession *session, MSIMessage *msg )
{
assert ( session );
if ( has_call_error ( session, msg ) == 0 )
return 0;
/* Act as end message */
MSIMessage *_msg_ending = msi_new_message ( TYPE_RESPONSE, stringify_response ( ending ) );
send_message ( session, _msg_ending, msg->friend_id );
free_message ( _msg_ending );
invoke_callback(MSI_OnCancel);
terminate_call ( session );
return 1;
}
int handle_recv_end ( MSISession *session, MSIMessage *msg )
{
assert ( session );
if ( has_call_error ( session, msg ) == 0 )
return 0;
MSIMessage *_msg_ending = msi_new_message ( TYPE_RESPONSE, stringify_response ( ending ) );
send_message ( session, _msg_ending, msg->friend_id );
free_message ( _msg_ending );
invoke_callback(MSI_OnEnd);
terminate_call ( session );
return 1;
}
/********** Response handlers **********/
int handle_recv_ringing ( MSISession *session, MSIMessage *msg )
{
assert ( session );
if ( has_call_error ( session, msg ) == 0 )
return 0;
session->call->ringing_timer_id = event.timer_alloc ( handle_timeout, session, session->call->ringing_tout_ms );
invoke_callback(MSI_OnRinging);
return 1;
}
int handle_recv_starting ( MSISession *session, MSIMessage *msg )
{
assert ( session );
if ( has_call_error ( session, msg ) == 0 )
return 0;
if ( !msg->cryptokey.header_value ) {
return handle_error ( session, error_no_crypto_key, msg->friend_id );
}
/* Generate local key/nonce to send */
session->call->key_local = calloc ( sizeof ( uint8_t ), crypto_box_KEYBYTES );
new_symmetric_key ( session->call->key_local );
session->call->nonce_local = calloc ( sizeof ( uint8_t ), crypto_box_NONCEBYTES );
new_nonce ( session->call->nonce_local );
/* Save peer key/nonce */
session->call->key_peer = calloc ( sizeof ( uint8_t ), crypto_box_KEYBYTES );
memcpy ( session->call->key_peer, msg->cryptokey.header_value, crypto_box_KEYBYTES );
session->call->nonce_peer = calloc ( sizeof ( uint8_t ), crypto_box_NONCEBYTES );
memcpy ( session->call->nonce_peer, msg->nonce.header_value, crypto_box_NONCEBYTES );
session->call->state = call_active;
MSIMessage *_msg_start = msi_new_message ( TYPE_REQUEST, stringify_request ( start ) );
msi_msg_set_cryptokey ( _msg_start, session->call->key_local, crypto_box_KEYBYTES );
msi_msg_set_nonce ( _msg_start, session->call->nonce_local, crypto_box_NONCEBYTES );
send_message ( session, _msg_start, msg->friend_id );
free_message ( _msg_start );
flush_peer_type ( session, msg, 0 );
invoke_callback(MSI_OnStarting);
event.timer_release ( session->call->ringing_timer_id );
return 1;
}
int handle_recv_ending ( MSISession *session, MSIMessage *msg )
{
assert ( session );
if ( has_call_error ( session, msg ) == 0 )
return 0;
/* Stop timer */
event.timer_release ( session->call->request_timer_id );
invoke_callback(MSI_OnEnding);
/* Terminate call */
terminate_call ( session );
return 1;
}
int handle_recv_error ( MSISession *session, MSIMessage *msg )
{
assert ( session );
assert ( session->call );
/* Handle error accordingly */
if ( msg->reason.header_value ) {
session->last_error_id = atoi ( ( const char * ) msg->reason.header_value );
session->last_error_str = stringify_error ( session->last_error_id );
}
invoke_callback(MSI_OnEnding);
terminate_call ( session );
return 1;
}
/**
* @brief BASIC call flow:
*
* ALICE BOB
* | invite --> |
* | |
* | <-- ringing |
* | |
* | <-- starting |
* | |
* | start --> |
* | |
* | <-- MEDIA TRANS --> |
* | |
* | end --> |
* | |
* | <-- ending |
*
* Alice calls Bob by sending invite packet.
* Bob recvs the packet and sends an ringing packet;
* which notifies Alice that her invite is acknowledged.
* Ringing screen shown on both sides.
* Bob accepts the invite for a call by sending starting packet.
* Alice recvs the starting packet and sends the started packet to
* inform Bob that she recved the starting packet.
* Now the media transmission is established ( i.e. RTP transmission ).
* Alice hangs up and sends end packet.
* Bob recves the end packet and sends ending packet
* as the acknowledgement that the call is ending.
*
*
*/
void msi_handle_packet ( Messenger *messenger, int source, uint8_t *data, uint16_t length, void *object )
{
/* Unused */
(void)messenger;
MSISession *_session = object;
MSIMessage *_msg;
if ( !length ) return;
_msg = parse_message ( data, length );
if ( !_msg ) return;
_msg->friend_id = source;
/* Now handle message */
if ( _msg->request.header_value ) { /* Handle request */
if ( _msg->response.size > 32 ) goto free_end;
uint8_t _request_value[32];
memcpy(_request_value, _msg->request.header_value, _msg->request.size);
_request_value[_msg->request.size] = '\0';
if ( same ( _request_value, stringify_request ( invite ) ) ) {
handle_recv_invite ( _session, _msg );
} else if ( same ( _request_value, stringify_request ( start ) ) ) {
handle_recv_start ( _session, _msg );
} else if ( same ( _request_value, stringify_request ( cancel ) ) ) {
handle_recv_cancel ( _session, _msg );
} else if ( same ( _request_value, stringify_request ( reject ) ) ) {
handle_recv_reject ( _session, _msg );
} else if ( same ( _request_value, stringify_request ( end ) ) ) {
handle_recv_end ( _session, _msg );
}
else goto free_end;
} else if ( _msg->response.header_value ) { /* Handle response */
if ( _msg->response.size > 32 ) goto free_end;
uint8_t _response_value[32];
memcpy(_response_value, _msg->response.header_value, _msg->response.size);
_response_value[_msg->response.size] = '\0';
if ( same ( _response_value, stringify_response ( ringing ) ) ) {
handle_recv_ringing ( _session, _msg );
} else if ( same ( _response_value, stringify_response ( starting ) ) ) {
handle_recv_starting ( _session, _msg );
} else if ( same ( _response_value, stringify_response ( ending ) ) ) {
handle_recv_ending ( _session, _msg );
} else if ( same ( _response_value, stringify_response ( error ) ) ) {
handle_recv_error ( _session, _msg );
} else goto free_end;
/* Got response so cancel timer */
if ( _session->call )
event.timer_release ( _session->call->request_timer_id );
}
free_end:free_message ( _msg );
}
/********************************************************************************************************************
* *******************************************************************************************************************
********************************************************************************************************************
********************************************************************************************************************
********************************************************************************************************************
*
*
*
* PUBLIC API FUNCTIONS IMPLEMENTATIONS
*
*
*
********************************************************************************************************************
********************************************************************************************************************
********************************************************************************************************************
********************************************************************************************************************
********************************************************************************************************************/
/**
* @brief Callback setter.
*
* @param callback The callback.
* @param id The id.
* @return void
*/
void msi_register_callback ( MSICallback callback, MSICallbackID id, void* userdata )
{
callbacks[id].function = callback;
callbacks[id].data = userdata;
}
/**
* @brief Start the control session.
*
* @param messenger Tox* object.
* @param user_agent User agent, i.e. 'Venom'; 'QT-gui'
* @return MSISession* The created session.
* @retval NULL Error occured.
*/
MSISession *msi_init_session ( Messenger* messenger )
{
assert ( messenger );
MSISession *_retu = calloc ( sizeof ( MSISession ), 1 );
assert ( _retu );
_retu->messenger_handle = messenger;
_retu->agent_handler = NULL;
_retu->call = NULL;
_retu->frequ = 10000; /* default value? */
_retu->call_timeout = 30000; /* default value? */
m_callback_msi_packet(messenger, msi_handle_packet, _retu );
/* This is called when remote terminates session */
m_callback_connectionstatus_internal_av(messenger, handle_remote_connection_change, _retu);
return _retu;
}
/**
* @brief Terminate control session.
*
* @param session The session
* @return int
*/
int msi_terminate_session ( MSISession *session )
{
assert ( session );
int _status = 0;
/* If have call, cancel it */
if ( session->call ) {
/* Cancel all? */
uint16_t _it = 0;
for ( ; _it < session->call->peer_count; _it++ )
msi_cancel ( session, session->call->peers [_it], "MSI session terminated!" );
}
m_callback_msi_packet((struct Messenger *) session->messenger_handle, NULL, NULL);
free ( session );
return _status;
}
/**
* @brief Send invite request to friend_id.
*
* @param session Control session.
* @param call_type Type of the call. Audio or Video(both audio and video)
* @param rngsec Ringing timeout.
* @param friend_id The friend.
* @return int
*/
int msi_invite ( MSISession *session, MSICallType call_type, uint32_t rngsec, uint32_t friend_id )
{
assert ( session );
MSIMessage *_msg_invite = msi_new_message ( TYPE_REQUEST, stringify_request ( invite ) );
session->call = init_call ( session, 1, rngsec ); /* Just one for now */
t_randomstr ( session->call->id, CALL_ID_LEN );
add_peer(session->call, friend_id );
session->call->type_local = call_type;
/* Do whatever with message */
if ( call_type == type_audio ) {
msi_msg_set_calltype
( _msg_invite, ( const uint8_t * ) CT_AUDIO_HEADER_VALUE, strlen ( CT_AUDIO_HEADER_VALUE ) );
} else {
msi_msg_set_calltype
( _msg_invite, ( const uint8_t * ) CT_VIDEO_HEADER_VALUE, strlen ( CT_VIDEO_HEADER_VALUE ) );
}
send_message ( session, _msg_invite, friend_id );
free_message ( _msg_invite );
session->call->state = call_inviting;
session->call->request_timer_id = event.timer_alloc ( handle_timeout, session, m_deftout );
return 0;
}
/**
* @brief Hangup active call.
*
* @param session Control session.
* @return int
* @retval -1 Error occured.
* @retval 0 Success.
*/
int msi_hangup ( MSISession *session )
{
assert ( session );
if ( !session->call || session->call->state != call_active )
return -1;
MSIMessage *_msg_end = msi_new_message ( TYPE_REQUEST, stringify_request ( end ) );
/* hangup for each peer */
int _it = 0;
for ( ; _it < session->call->peer_count; _it ++ )
send_message ( session, _msg_end, session->call->peers[_it] );
free_message ( _msg_end );
session->call->request_timer_id = event.timer_alloc ( handle_timeout, session, m_deftout );
return 0;
}
/**
* @brief Answer active call request.
*
* @param session Control session.
* @param call_type Answer with Audio or Video(both).
* @return int
*/
int msi_answer ( MSISession *session, MSICallType call_type )
{
assert ( session );
MSIMessage *_msg_starting = msi_new_message ( TYPE_RESPONSE, stringify_response ( starting ) );
session->call->type_local = call_type;
if ( call_type == type_audio ) {
msi_msg_set_calltype
( _msg_starting, ( const uint8_t * ) CT_AUDIO_HEADER_VALUE, strlen ( CT_AUDIO_HEADER_VALUE ) );
} else {
msi_msg_set_calltype
( _msg_starting, ( const uint8_t * ) CT_VIDEO_HEADER_VALUE, strlen ( CT_VIDEO_HEADER_VALUE ) );
}
/* Now set the local encryption key and pass it with STARTING message */
session->call->key_local = calloc ( sizeof ( uint8_t ), crypto_box_KEYBYTES );
new_symmetric_key ( session->call->key_local );
session->call->nonce_local = calloc ( sizeof ( uint8_t ), crypto_box_NONCEBYTES );
new_nonce ( session->call->nonce_local );
msi_msg_set_cryptokey ( _msg_starting, session->call->key_local, crypto_box_KEYBYTES );
msi_msg_set_nonce ( _msg_starting, session->call->nonce_local, crypto_box_NONCEBYTES );
send_message ( session, _msg_starting, session->call->peers[session->call->peer_count - 1] );
free_message ( _msg_starting );
session->call->state = call_active;
return 0;
}
/**
* @brief Cancel request.
*
* @param session Control session.
* @param reason Set optional reason header. Pass NULL if none.
* @return int
*/
int msi_cancel ( MSISession *session, uint32_t peer, const char *reason )
{
assert ( session );
MSIMessage *_msg_cancel = msi_new_message ( TYPE_REQUEST, stringify_request ( cancel ) );
if ( reason ) msi_msg_set_reason(_msg_cancel, (const uint8_t*)reason, strlen(reason));
send_message ( session, _msg_cancel, peer );
free_message ( _msg_cancel );
session->call->request_timer_id = event.timer_alloc ( handle_timeout, session, m_deftout );
return 0;
}
/**
* @brief Reject request.
*
* @param session Control session.
* @return int
*/
int msi_reject ( MSISession *session, const uint8_t *reason )
{
assert ( session );
MSIMessage *_msg_reject = msi_new_message ( TYPE_REQUEST, stringify_request ( reject ) );
if ( reason ) msi_msg_set_reason(_msg_reject, reason, strlen((const char *)reason) + 1);
send_message ( session, _msg_reject, session->call->peers[session->call->peer_count - 1] );
free_message ( _msg_reject );
session->call->request_timer_id = event.timer_alloc ( handle_timeout, session, m_deftout );
return 0;
}
/**
* @brief Terminate the current call.
*
* @param session Control session.
* @return int
*/
int msi_stopcall ( MSISession *session )
{
assert ( session );
if ( !session->call )
return -1;
/* just terminate it */
terminate_call ( session );
return 0;
}