ospf_shortest_path_calculation.c

vxworks下ospf协议栈

        {
        sptr_next_hop = ospf_create_next_hop_block ();
        if (sptr_next_hop != NULL)
            {
            sptr_next_hop->next_hop_router = best_neighbor->address;
#if defined (__UNNUMBERED_LINK__)
            if (best_neighbor->sptr_interface->address == 0x00000000L)
                {
                sptr_next_hop->outgoing_router_interface = best_neighbor->sptr_interface->port_number;
                }
            else
                {
                sptr_next_hop->outgoing_router_interface = best_neighbor->sptr_interface->address;
                }
#else /* __UNNUMBERED_LINK__ */
            sptr_next_hop->outgoing_router_interface = best_neighbor->sptr_interface->address;
#endif /* __UNNUMBERED_LINK__ */
            return (sptr_next_hop);
            }
        }

 	sptr_next_hop = ospf_inherit_the_set_of_next_hops_from_node_X (sptr_parent->sptr_next_hop);


	return (sptr_next_hop);
}
/**********************************************************************************************************************************/
static OSPF_NEXT_HOP_BLOCK *ospf_set_next_hop_when_parent_vertex_is_this_router (OSPF_SHORTEST_PATH_NODE *sptr_destination, OSPF_ROUTER_LINK_PIECE *sptr_link, OSPF_AREA_ENTRY *sptr_area)
{
	OSPF_NEXT_HOP_BLOCK *sptr_next_hop;
	OSPF_INTERFACE *sptr_interface = NULL;
	OSPF_INTERFACE *sptr_next_interface = NULL;
	ULONG router;
	ULONG interface_address = 0x00000000;
	ULONG next_hop_router = 0x00000000;
	ULONG stub_net;

	OSPF_PRINTF_DEBUG (OSPF_DEBUG_PRINTF, "OSPF: Entering ospf_set_next_hop_when_parent_vertex_is_this_router\r\n");

	sptr_next_hop = NULL;

	if (sptr_link == NULL)
		{
		sptr_next_hop = ospf_create_next_hop_block ();

		if (sptr_next_hop != NULL)
			{
			sptr_next_hop->outgoing_router_interface = ospf_find_outgoing_interface_for_router (sptr_destination->vertex, interface_address, &next_hop_router);
			}
		else
			{
			return NULL;
			}
		}
	else if (sptr_link->type == OSPF_ROUTER_LINK_TYPE_VIRTUAL)
		{
		return (NULL);		/* defer the setting of the next hop until the calculation in Section 16.3 */
		}
	else
		{
		sptr_next_hop = ospf_create_next_hop_block ();

		if (sptr_next_hop != NULL)
			{
			switch (sptr_link->type)
				{
				case OSPF_ROUTER_LINK_TYPE_PPP:
					{
					router = sptr_link->link_id;
					router = net_to_host_long (router);
					interface_address = sptr_link->link_data;
					interface_address = net_to_host_long(interface_address);
					sptr_next_hop->outgoing_router_interface = ospf_find_outgoing_interface_for_router (router, interface_address, &next_hop_router);
					sptr_next_hop->next_hop_router = next_hop_router;
					break;
					}

				case OSPF_ROUTER_LINK_TYPE_TRANSIT_NETWORK:
					{
					sptr_next_hop->outgoing_router_interface = sptr_link->link_data;
					sptr_next_hop->outgoing_router_interface = net_to_host_long (sptr_next_hop->outgoing_router_interface);

					break;
					}

				case OSPF_ROUTER_LINK_TYPE_STUB_NETWORK:
					{
					stub_net = net_to_host_long (sptr_link->link_id);

					for (sptr_interface = sptr_area->sptr_interfaces; sptr_interface != NULL; sptr_interface = sptr_next_interface)
						{
						sptr_next_interface = sptr_interface->sptr_forward_link;
						if (sptr_interface->area_id == sptr_area->area_id)
							{
							if (stub_net == (sptr_interface->address & sptr_interface->netmask) )
								{
#if defined (__UNNUMBERED_LINK__ )
								if (sptr_interface->address == 0x00000000) /* unnumbered link */
									{
									sptr_next_hop->outgoing_router_interface = sptr_interface->port_number;
									}
								else
									{
 									sptr_next_hop->outgoing_router_interface = sptr_interface->address;
									}
#else /* __UNNUMBERED_LINK__  */
					 			sptr_next_hop->outgoing_router_interface = sptr_interface->address;
#endif /* __UNNUMBERED_LINK__  */


								break;
								}
                            /* Fix for TSR 297651 (SPR# 83274) */
                            else if ((sptr_interface->type == OSPF_POINT_TO_POINT) && 
                                     (sptr_interface->sptr_neighbor != NULL) &&
                                     (sptr_interface->sptr_neighbor->address == stub_net))
                                {
#if defined (__UNNUMBERED_LINK__)
								if (sptr_interface->address == 0x00000000) /* unnumbered link */
									{
									sptr_next_hop->outgoing_router_interface = sptr_interface->port_number;
									}
								else
									{
 									sptr_next_hop->outgoing_router_interface = sptr_interface->address;
									}
#else /* __UNNUMBERED_LINK__  */
					 			sptr_next_hop->outgoing_router_interface = sptr_interface->address;
#endif /* __UNNUMBERED_LINK__  */
                                }
							}
						}
					break;
					}

				default:
					{
					table_free (sptr_next_hop);

					sptr_next_hop = NULL;

					break;
					}
				}
			}
		}

	return (sptr_next_hop);

}
/**********************************************************************************************************************************/
static OSPF_NEXT_HOP_BLOCK *ospf_set_outgoing_interface_for_a_locally_attached_stub_network (OSPF_ROUTING_TABLE_ENTRY *sptr_routing_table_entry,
	OSPF_AREA_ENTRY *sptr_area)
{
	OSPF_INTERFACE *sptr_interface = NULL;
	OSPF_INTERFACE *sptr_next_interface = NULL;
	OSPF_NEXT_HOP_BLOCK *sptr_next_hop;

	OSPF_PRINTF_DEBUG (OSPF_DEBUG_PRINTF, "OSPF: Entering ospf_set_outgoing_interface_for_a_locally_attached_stub_network\r\n");

	if (sptr_area == NULL)
		{
		return (NULL);
		}

 	for (sptr_interface = ospf.sptr_interface_list; sptr_interface != NULL; sptr_interface = sptr_next_interface)
 		{
		sptr_next_interface = sptr_interface->sptr_forward_link;
		if (sptr_interface->area_id == sptr_area->area_id)
			{
	 		if ( (sptr_interface->address & sptr_interface->netmask) == (sptr_routing_table_entry->destination_id & sptr_routing_table_entry->address_mask) )
 				{
 				sptr_next_hop = (OSPF_NEXT_HOP_BLOCK *) table_malloc (1, sizeof (OSPF_NEXT_HOP_BLOCK));

				if (sptr_next_hop != NULL)
					{
					memset (sptr_next_hop, 0x00, sizeof (OSPF_NEXT_HOP_BLOCK) );
					}
				else
					{
					ospf_print_memory_error_message_and_free_buffer_if_necessary ((void *) NULL, "Function: ospf_set_outgoing_interface_for_a_locally_attached_stub_network  OSPF_NEXT_HOP_BLOCK");

					return (NULL);
					}

	 			sptr_next_hop->next_hop_router = 0x00000000L;

#if defined (__UNNUMBERED_LINK__ )
				if (sptr_interface->address == 0x00000000) /* unnumbered link */
					{
					sptr_routing_table_entry->sptr_next_hop->outgoing_router_interface = sptr_interface->port_number;
					}
				else
					{
 					sptr_next_hop->outgoing_router_interface = sptr_interface->address;
					}
#else /* __UNNUMBERED_LINK__  */
	 			sptr_next_hop->outgoing_router_interface = sptr_interface->address;
#endif /* __UNNUMBERED_LINK__  */

				return (sptr_next_hop);
 				}
 			}
		}

	return (NULL);
}
/**********************************************************************************************************************************/
static enum TEST ospf_check_if_link_exists_for_ls_header_type_of_ls_router (UNION_OSPF_LINK_STATE_ADVERTISEMENT *sptr_advertisement,ULONG vertex,OSPF_AREA_ENTRY *sptr_area)
{
	OSPF_ROUTER_LINK_PIECE *sptr_router_link;
	USHORT number_of_links;
	ULONG link_id;
	ULONG link_data;
	OSPF_LS_DATABASE_ENTRY *sptr_database_entry;
	enum TEST test_return_type;
	char print_buffer[PRINT_BUFFER_SIZE];

	OSPF_PRINTF_DEBUG (OSPF_DEBUG_PRINTF, "OSPF: Entering ospf_check_if_link_exists_for_ls_header_type_of_ls_router\r\n");

  	sptr_router_link = &sptr_advertisement->sptr_router->link;

  	number_of_links = sptr_advertisement->sptr_router->number_of_links;
  	number_of_links = net_to_host_short (number_of_links);

  	for (; number_of_links > 0x0000; --number_of_links)
  		{
  		switch (sptr_router_link->type)
  			{
  			case OSPF_ROUTER_LINK_TYPE_PPP:
  			case OSPF_ROUTER_LINK_TYPE_VIRTUAL:
  				{
  				link_id = sptr_router_link->link_id;
  				link_id = net_to_host_long (link_id);

  				if (vertex == link_id)
  					{
  					return (PASS);
  					}
  				}

				break; /*#$-NOTE:note19-$#*/

  			case OSPF_ROUTER_LINK_TYPE_TRANSIT_NETWORK:
  				{
  				link_data = sptr_router_link->link_data;
  				link_data = net_to_host_long (link_data);

  				OSPF_CONVERT_IP_ADDRESS_TO_DOT_FORMAT_FOR_DEBUG (print_buffer, link_data);

 	  			OSPF_PRINTF_DEBUG (OSPF_DEBUG_PRINTF, "OSPF:    link_data = %s\n", print_buffer);

	  			if (link_data == vertex)
	  				{
	  				return (PASS);
	  				}
	  			else
	  				{
	  				link_id = sptr_router_link->link_id;
	  				link_id = net_to_host_long (link_id);

					/* SPR#76812 -- Begin */
					sptr_database_entry = ospf_find_LSA (sptr_area, link_id, 0x00000000L, OSPF_LS_NETWORK);
					/* SPR#76812 -- End */

					if (sptr_database_entry != NULL)
						{
						test_return_type = ospf_check_if_link_exists (&sptr_database_entry->advertisement, vertex, sptr_area);

						if (test_return_type == PASS)
							{
							return (PASS);
							}
						}
					}

				break;
				}

			case OSPF_ROUTER_LINK_TYPE_STUB_NETWORK:
				{
				return (PASS);

				break;
				}

		  	default:
		  		{
		  		break;
		  		}
		  	}

	  	sptr_router_link = (OSPF_ROUTER_LINK_PIECE *) ((ULONG) sptr_router_link + OSPF_ROUTER_LINK_PIECE_SIZE +
	  		((sptr_router_link->number_of_metrics) * OSPF_ROUTER_LINK_METRIC_PIECE_SIZE));
	  	}

  	return (FAIL);
}
/********************************************************************************/