osip_transaction.c

SIP协议栈实现

	       "sipevent tr->state: %i\n", transaction->state));
  OSIP_TRACE (osip_trace
	      (__FILE__, __LINE__, OSIP_INFO4, NULL,
	       "sipevent evt->type: %i\n", evt->type));
  OSIP_TRACE (osip_trace
	      (__FILE__, __LINE__, OSIP_INFO4, NULL,
	       "sipevent evt->sip: %x\n", evt->sip));

  if (transaction->ctx_type == ICT)
    statemachine = __ict_get_fsm ();
  else if (transaction->ctx_type == IST)
    statemachine = __ist_get_fsm ();
  else if (transaction->ctx_type == NICT)
    statemachine = __nict_get_fsm ();
  else
    statemachine = __nist_get_fsm ();


  if (-1 == fsm_callmethod (evt->type,
			    transaction->state, statemachine, evt,
			    transaction))
    {
      OSIP_TRACE (osip_trace
		  (__FILE__, __LINE__, OSIP_INFO3, NULL, "USELESS event!\n"));
      /* message is useless. */
      if (EVT_IS_MSG (evt))
	{
	  if (evt->sip != NULL)
	    {
	      osip_message_free (evt->sip);
	    }
	}
    }
  else
    {
      OSIP_TRACE (osip_trace
		  (__FILE__, __LINE__, OSIP_INFO4, NULL,
		   "sipevent evt: method called!\n"));
    }
  osip_free (evt);  /* this is the ONLY place for freeing event!! */
  return 1;
}

int
osip_transaction_get_destination(osip_transaction_t * transaction, char **ip, int *port)
{
  *ip=NULL;
  *port=0;
  if (transaction==NULL) return -1;
  if (transaction->ict_context!=NULL)
    {
      *ip = transaction->ict_context->destination;
      *port = transaction->ict_context->port;
      return 0;
    }
  else if (transaction->nict_context!=NULL)
    {
      *ip = transaction->nict_context->destination;
      *port = transaction->nict_context->port;
      return 0;
    }
  return -1;
}

int
osip_transaction_set_your_instance (osip_transaction_t * transaction, void *instance)
{
  if (transaction == NULL)
    return -1;
  transaction->your_instance = instance;
  return 0;
}

void *
osip_transaction_get_your_instance (osip_transaction_t * transaction)
{
  if (transaction == NULL)
    return NULL;
  return transaction->your_instance;
}

int
__osip_transaction_set_state (osip_transaction_t * transaction, state_t state)
{
  if (transaction == NULL)
    return -1;
  transaction->state = state;
  return 0;
}

int
osip_transaction_set_in_socket (osip_transaction_t * transaction, int sock)
{
  if (transaction == NULL)
    return -1;
  transaction->in_socket = sock;
  return 0;
}

int
osip_transaction_set_out_socket (osip_transaction_t * transaction, int sock)
{
  if (transaction == NULL)
    return -1;
  transaction->out_socket = sock;
  return 0;
}

int
__osip_transaction_matching_response_osip_to_xict_17_1_3 (osip_transaction_t * tr,
							  osip_message_t * response)
{
  osip_generic_param_t *b_request;
  osip_generic_param_t *b_response;
  osip_via_t *topvia_response;

  /* some checks to avoid crashing on bad requests */
  if (tr == NULL || (tr->ict_context == NULL && tr->nict_context == NULL) ||
      /* only ict and nict can match a response */
      response == NULL || response->cseq == NULL
      || response->cseq->method == NULL)
    return -1;

  topvia_response = osip_list_get (response->vias, 0);
  if (topvia_response == NULL)
    {
      OSIP_TRACE (osip_trace
		  (__FILE__, __LINE__, OSIP_ERROR, NULL,
		   "Remote UA is not compliant: missing a Via header!\n"));
      return -1;
    }
  osip_via_param_get_byname (tr->topvia, "branch", &b_request);
  if (b_request == NULL)
    {
      OSIP_TRACE (osip_trace
		  (__FILE__, __LINE__, OSIP_BUG, NULL,
		   "You created a transaction without any branch! THIS IS NOT ALLOWED\n"));
      return -1;
    }
  osip_via_param_get_byname (topvia_response, "branch", &b_response);
  if (b_response == NULL)
    {
#ifdef FWDSUPPORT
      /* the from tag (unique) */
      if (from_tag_match(tr->from, response->from)!=0)
	return -1;
      /* the Cseq field */
      if (cseq_match(tr->cseq, response->cseq)!=0)
	return -1;
      /* the To field */
      if (response->to->url->username==NULL && tr->from->url->username!=NULL)
	return -1;
      if (response->to->url->username!=NULL && tr->from->url->username==NULL)
	return -1;
      if (response->to->url->username!=NULL && tr->from->url->username!=NULL)
	{
	  if (strcmp(response->to->url->host, tr->from->url->host) ||
	      strcmp(response->to->url->username, tr->from->url->username))
	    return -1;
	}
      else
	{
	  if (strcmp(response->to->url->host, tr->from->url->host))
	    return -1;
	}

      /* the Call-ID field */
      if (call_id_match(tr->callid, response->call_id)!=0)
	return -1;
      return 0;
#else
      OSIP_TRACE (osip_trace
		  (__FILE__, __LINE__, OSIP_BUG, NULL,
		   "Remote UA is not compliant: missing a branch parameter in  Via header!\n"));
      return -1;
#endif
    }

  /*
     A response matches a client transaction under two
     conditions:

     1.   If the response has the same value of the branch parameter
     in the top Via header field as the branch parameter in the
     top Via header field of the request that created the
     transaction.
   */
  if (0 != strcmp (b_request->gvalue, b_response->gvalue))
    return -1;
  /*  
     2.   If the method parameter in the CSeq header field matches
     the method of the request that created the transaction. The
     method is needed since a CANCEL request constitutes a
     different transaction, but shares the same value of the
     branch parameter.
     AMD NOTE: cseq->method is ALWAYS the same than the METHOD of the request.
   */
  if (0 == strcmp (response->cseq->method, tr->cseq->method))	/* general case */
    return 0;
  return -1;
}

int
__osip_transaction_matching_request_osip_to_xist_17_2_3 (osip_transaction_t * tr,
							 osip_message_t * request)
{
  osip_generic_param_t *b_origrequest;
  osip_generic_param_t *b_request;
  osip_via_t *topvia_request;
  int length_br;
  int length_br2;

  /* some checks to avoid crashing on bad requests */
  if (tr == NULL || (tr->ist_context == NULL && tr->nist_context == NULL) ||
      /* only ist and nist can match a request */
      request == NULL || request->cseq == NULL
      || request->cseq->method == NULL)
    return -1;

  topvia_request = osip_list_get (request->vias, 0);
  if (topvia_request == NULL)
    {
      OSIP_TRACE (osip_trace
		  (__FILE__, __LINE__, OSIP_ERROR, NULL,
		   "Remote UA is not compliant: missing a Via header!\n"));
      return -1;
    }
  osip_via_param_get_byname (topvia_request, "branch", &b_request);
  osip_via_param_get_byname (tr->topvia, "branch", &b_origrequest);

  if ((b_origrequest == NULL && b_request != NULL) ||
      (b_origrequest != NULL && b_request == NULL))
    return -1; /* one request is compliant, the other one is not... */

  /* Section 17.2.3 Matching Requests to Server Transactions:
     "The branch parameter in the topmost Via header field of the request
     is examined. If it is present and begins with the magic cookie
     "z9hG4bK", the request was generated by a client transaction
     compliant to this specification."
   */

  if (b_origrequest != NULL && b_request != NULL)
    /* case where both request contains a branch */
    {
      length_br = strlen (b_origrequest->gvalue);
      length_br2 = strlen (b_request->gvalue);
      if (length_br != length_br2)
	return -1;		/* can't be the same */
      if (0 == strncmp (b_origrequest->gvalue, "z9hG4bK", 7)
	  && 0 == strncmp (b_request->gvalue, "z9hG4bK", 7))
	{
	  /* both request comes from a compliant UA */
	  /* The request matches a transaction if the branch parameter
	     in the request is equal to the one in the top Via header
	     field of the request that created the transaction, the
	     sent-by value in the top Via of the request is equal to
	     the one in the request that created the transaction, and in
	     the case of a CANCEL request, the method of the request
	     that created the transaction was also CANCEL.
	   */
	  if (0 != strcmp (b_origrequest->gvalue, b_request->gvalue))
	    return -1;		/* bracnh param does not match */
	  osip_via_param_get_byname (topvia_request, "sent-by", &b_request);
	  osip_via_param_get_byname (tr->topvia, "sent-by", &b_origrequest);
	  if ((b_request != NULL && b_origrequest == NULL) ||
	      (b_request == NULL && b_origrequest != NULL))
	    return -1;		/* sent-by param does not match */
	  if (b_request != NULL	/* useless  && b_origrequest!=NULL */
	      && 0 != strcmp (b_origrequest->gvalue, b_request->gvalue))
	    return -1;
#ifdef AC_BUG
	  /* audiocodes bug (MP108-fxs-SIP-4-0-282-380) */
	  if (0 != osip_from_tag_match (tr->from, request->from))
	    return -1;
#endif
	  if (b_request != NULL	/* useless  && b_origrequest!=NULL */
	      && 0 != strcmp (b_origrequest->gvalue, b_request->gvalue))
	    return -1;
	  if (			/* MSG_IS_CANCEL(request)&& <<-- BUG from the spec?
				   I always check the CSeq */
	       (!(0 == strcmp (tr->cseq->method, "INVITE") &&
		  0 == strcmp (request->cseq->method, "ACK")))
	       && 0 != strcmp (tr->cseq->method, request->cseq->method))
	    return -1;
	  return 0;
	}
    }

  /* Back to the old backward compatibilty mechanism for matching requests */
  if (0 != osip_call_id_match (tr->callid, request->call_id))
    return -1;
  if (MSG_IS_ACK (request))
    {
      osip_generic_param_t *tag_from1;
      osip_generic_param_t *tag_from2;

      osip_from_param_get_byname (tr->to, "tag", &tag_from1);
      osip_from_param_get_byname (request->to, "tag", &tag_from2);
      if (tag_from1 == NULL && tag_from2 != NULL)
	{			/* do not check it as it can be a new tag when the final
				   answer has a tag while an INVITE doesn't have one */
	}
      else if (tag_from1 != NULL && tag_from2 == NULL)
	{
	  return -1;
	}
      else
	{
	  if (0 != osip_to_tag_match (tr->to, request->to))
	    return -1;
	}
    }
  else
    {
      if (0 != osip_to_tag_match (tr->to, request->to))
	return -1;
    }
  if (0 != osip_from_tag_match (tr->from, request->from))
    return -1;
  if (0 != osip_cseq_match (tr->cseq, request->cseq))
    return -1;
  if (0 != osip_via_match (tr->topvia, topvia_request))
    return -1;
  return 0;
}

#if 0

int
callleg_match (osip_to_t * to1, osip_from_t * from1, osip_to_t * to2, osip_from_t * from2)
{
  if (to1 == NULL || to2 == NULL)
    return -1;
  if (from1 == NULL || from2 == NULL)
    return -1;

  if (0 == osip_from_compare ((osip_from_t *) to1, (osip_from_t *) to2)
      && 0 == osip_from_compare (from1, from2))
    return 0;
  return -1;
}

#endif