tora.cc

这是网络仿真中TORA的最新研究成果

		Time delay = 0.0;

		while((p0 = rqueue.deque(td->index))) {
                        forward(p0, tn->index, delay);
			delay += ARP_SEPARATION_DELAY;
		}
	}
	Packet::free(p);
}



/*
 *  IETF Draft - TORA Specification, section 3.7.6
 */
void
toraAgent::recvQRY(Packet *p)
{
	struct hdr_ip *ih = HDR_IP(p);
	struct hdr_tora_qry *qh = HDR_TORA_QRY(p);
	TORADest *td;
	TORANeighbor *tn;

	if(qh->tq_dst == ipaddr()) {
#ifdef DEBUG
		fprintf(stderr, "node %d received `QRY` for itself.\n", index);
#endif
		return;
	}

	td = dst_find(qh->tq_dst);
	if(td == 0)
		td = dst_add(qh->tq_dst);

	if(td->rt_req) {
		return;
	}

	if(td->height.r == 0) {					// II, A
		tn = td->nb_find(ih->saddr());

		if(tn && tn->time_act > td->time_upd) {		// II, A, 1
			td->time_upd = Scheduler::instance().clock();
			sendUPD(td->index);
		}
		else {						// II, A, 2
		}
	}
	else {
		tn = td->nb_find_min_height(0);

		if(tn) {					// II, B, 1
			td->update_height(tn->height.tau,
					  tn->height.oid,
					  tn->height.r,
					  tn->height.delta + 1,
					  ipaddr());

			td->time_upd = Scheduler::instance().clock();

			sendUPD(td->index);
		}
		else {
			td->rt_req = 1;
			td->time_rt_req = CURRENT_TIME;

			if(td->num_active > 1) {		// II, B, 1, a
				sendQRY(td->index);
			}
			else {					// II, B, 1, b

			}
		}
	}
}


/*
 *  IETF Draft - TORA Specification, section 3.7.7
 */
void
toraAgent::recvUPD(Packet *p)
{
	struct hdr_ip *ih = HDR_IP(p);
	struct hdr_tora_upd *uh = HDR_TORA_UPD(p);
	TORADest *td;
	TORANeighbor *tn;

	if(uh->tu_dst == ipaddr()) {
		return;
	}

	td = dst_find(uh->tu_dst);
	if(td == 0)
		td = dst_add(uh->tu_dst);

	tn = td->nb_find(ih->saddr());
	if(tn == 0) {
		/*
		 * update link status? -josh
		 */

	         // No, don't update linkstatus: it may be an update
	         // that was delayed in the IMEP layer for sequencing -dam
	         // no way at the TORA level to tell if we're connected...
	         trace("T %.9f _%d_ received `UPD` from non-neighbor %d",
		       CURRENT_TIME, ipaddr(), ih->saddr());		 
#ifdef DEBUG
		fprintf(stderr,
                        "node %d received `UPD` from non-neighbor %d\n",
			index, ih->src_);
#endif
		return;
	}

	/*
	 *  Update height and link status for neighbor [j][k].
	 */
	td->update_height_nb(tn, uh);

	if(td->rt_req && tn->height.r == 0) {								// I

		td->update_height(tn->height.tau,
				  tn->height.oid,
				  tn->height.r,
				  tn->height.delta + 1,
				  ipaddr());

		td->rt_req = 0;

		td->time_upd = Scheduler::instance().clock();

		sendUPD(td->index);
	}
	else if(td->num_down == 0) {									// II
		if(td->num_up == 0) {									// II, A
			if(td->height.isNull())								// II, A, 1
				return;									// II, A, 1, a
			else {
				td->height.Null();							// II, A, 1, b 

				td->time_upd = Scheduler::instance().clock();

				sendUPD(td->index);
			}
		}
		else {
			if(td->nb_check_same_ref()) {							// II, A, 2
				TORANeighbor *tn;

				if( (tn = td->nb_find_min_height(0)) ) {			// II, A, 2, a
					td->update_height(tn->height.tau,				// II, A, 2, a, i 
							  tn->height.oid,
							  1,
							  0,
							  ipaddr());
					td->time_upd = Scheduler::instance().clock();

					sendUPD(td->index);
				}
				else {
					if(td->height.oid == ipaddr()) {					// II, A, 2, a, ii
						double temp_tau = td->height.tau;			// II, A, 2, a, ii, x 
						nsaddr_t temp_oid = td->height.oid;

						td->height.Null();
						td->num_down = 0;
						td->num_up = 0;

						/*
						 *  For every active link n, if the neighbor connected
						 *  via link n is the destination j, set HT_NEIGH[j][n]=ZERO
						 *  and LNK_STAT[j][n] = DN.
						 *  Otherwise, set HT_NEIGH[j][n] = NULL and LNK_STAT[j][n] = UN.
						 */
						for(tn = td->nblist.lh_first; tn; tn = tn->link.le_next) {
							if(tn->index == td->index) {
								tn->height.Zero();
								tn->lnk_stat = LINK_DN;

							}
							else {
								tn->height.Null();
								tn->lnk_stat = LINK_UN;
							}
						}

						sendCLR(td->index, temp_tau, temp_oid);
					}
					else {
						td->update_height(Scheduler::instance().clock(),	// II, A, 2, a, ii, y
								  ipaddr(),
								  0,
								  0,
								  ipaddr());
						td->rt_req = 0;
						td->time_upd = Scheduler::instance().clock();

#ifdef DEBUG
						// under what circumstances does this rule fire?
						// seems like it will prevent the detection of 
						// partitions...??? -dam 8/24/98

						if (logtarget) 
						  {
						    sprintf(logtarget->pt_->buffer(), "T %.9f _%d_ rule IIA2a(ii)x fires %d",
							    Scheduler::instance().clock(), ipaddr(), td->index);
						    logtarget->pt_->dump();
						  }
#endif
						sendUPD(td->index);
					}
				}

			}
			else {
				TORANeighbor *n = td->nb_find_max_height();				// II, A, 2, b
				assert(n);
				TORANeighbor *m = td->nb_find_min_nonnull_height(&n->height);
				assert(m);

				td->update_height(m->height.tau,
						  m->height.oid,
						  m->height.r,
						  m->height.delta - 1,
						  ipaddr());

				td->time_upd = Scheduler::instance().clock();

				sendUPD(td->index);
			}
		}
	}
	else {												// II, B

	}
}


/*
 *  IETF Draft - TORA Specification, section 3.7.8
 */
void
toraAgent::recvCLR(Packet *p)
{
	struct hdr_ip *ih = HDR_IP(p);
	struct hdr_tora_clr *th = HDR_TORA_CLR(p);
	TORADest *td;
	TORANeighbor *tn;

	if(th->tc_dst == ipaddr()) {
		return;
	}

	td = dst_find(th->tc_dst);
	if(td == 0)
		td = dst_add(th->tc_dst);
	assert(td);

	if(td->height.tau == th->tc_tau &&
	   td->height.oid == th->tc_oid &&
	   td->height.r == 1) {					// I
		double temp_tau = td->height.tau;
		nsaddr_t temp_oid = td->height.oid;

		td->height.Null();
		td->num_up = 0;
		td->num_down = 0;

		for(tn = td->nblist.lh_first; tn; tn = tn->link.le_next) {
			if(tn->index == td->index) {
				tn->height.Zero();
				tn->lnk_stat = LINK_DN;
			}
			else {
				tn->height.Null();
				tn->lnk_stat = LINK_UN;
			}
		}
		if(td->num_active > 1) {			// I, A
			sendCLR(td->index, temp_tau, temp_oid);
		}
		else {						// I, B
		}
	}
	else {
		tn = td->nb_find(ih->saddr());			// II
		if(tn == 0) {
			/*
			 *  XXX - update link status?
			 */
		        trace("T %.9f _%d_ received `CLR` from non-neighbor %d",
		               CURRENT_TIME, index, ih->saddr());		
#ifdef DEBUG
			fprintf(stderr,
				"node %d received `CLR` from non-neighbor %d\n",
				index, ih->src_);
#endif
			return;
		}

		tn->height.Null();
		tn->lnk_stat = LINK_UN;

		for(tn = td->nblist.lh_first; tn; tn = tn->link.le_next) {
			if(tn->height.tau == th->tc_tau &&
			   tn->height.oid == th->tc_oid &&
			   tn->height.r == 1) {
				tn->height.Null();
				tn->lnk_stat = LINK_UN;
                        }
		}
		if(td->num_down == 0) {				// II, A
			if(td->num_up == 0) {			// II, A, 1
				if(td->height.isNull()) {	// II, A, 1, a
				}
				else {
					td->height.Null();
					td->time_upd = Scheduler::instance().clock();
					sendUPD(td->index);
				}
			}
			else {
				td->update_height(Scheduler::instance().clock(),
						  ipaddr(),
						  0,
						  0,
						  ipaddr());
				td->rt_req = 0;
				td->time_upd = Scheduler::instance().clock();
				sendUPD(td->index);
			}
		}
		else {
								// II, B
		}
	}
}

void
toraAgent::trace(char* fmt, ...)
{
  va_list ap;
  
  if (!logtarget) return;

  va_start(ap, fmt);
  vsprintf(logtarget->pt_->buffer(), fmt, ap);
  logtarget->pt_->dump();
  va_end(ap);
}