ospf_link_state_advertisements.c

vxworks下ospf协议栈

                {
                continue;
                }

            /* section 12.4.1, third bullet item (page 119) */

            if (sptr_interface->state == OSPF_INTERFACE_LOOPBACK)
                {
                if ((sptr_interface->type != OSPF_POINT_TO_POINT) || (sptr_interface->address != 0x00000000L))
                    {
                    sptr_link = ospf_add_a_link_description_to_the_router_advertisement (sptr_link, sptr_interface->address, OSPF_HOST_NET_MASK,
                        OSPF_ROUTER_LINK_TYPE_STUB_NETWORK, 0x00, 0x0000, &(sptr_router_link_advertisement->number_of_links), sptr_length);
                    }
                }
            else
                {
                /* section 12.4.1, fourth bullet item (page 119) */

                switch (sptr_interface->type)
                    {
                    case OSPF_POINT_TO_POINT:                                                           /* section 12.4.1.1 (page 119-120) */
                        {
                        if (sptr_interface->sptr_neighbor != NULL)
                            {
                            if (sptr_interface->sptr_neighbor->state == OSPF_NEIGHBOR_FULL)
                                {
                                /* section 12.4.1.1, first bullet item (page 119-120) */

                                if (sptr_interface->address != 0x00000000L)
                                    {
                                    link_data = sptr_interface->address;
                                    }
                                else
                                    {
                                    /* this field is supposed to be set to the MIB-II ifIndex value for unnumbered links RFC 1583 Appendix A4.2 */
#if defined (__UNNUMBERED_LINK__)
                                    link_data = sptr_interface->port_number;
#else /* __UNNUMBERED_LINK__ */
                                    link_data = sptr_interface->address;
#endif /* __UNNUMBERED_LINK__ */
                                    }

                                sptr_link = ospf_add_a_link_description_to_the_router_advertisement (sptr_link, sptr_interface->sptr_neighbor->id, link_data,
                                    OSPF_ROUTER_LINK_TYPE_PPP, 0x00, sptr_interface->cost, &(sptr_router_link_advertisement->number_of_links),
                                    sptr_length);
                                }
                            }

                            /* section 12.4.1.1, second bullet item (page 120) */

#if !defined (__UNNUMBERED_LINK__)
#if defined (__RFC_2328__)
                        switch (ospf.ospf_point_to_point_router_lsa_option)
                            {
                            case 1:
                                if (sptr_interface->sptr_neighbor != NULL)
                                    {
                                    if (sptr_interface->sptr_neighbor->address != 0x00000000L)                  /* Option 1 */
                                        {
                                        sptr_link = ospf_add_a_link_description_to_the_router_advertisement (sptr_link, sptr_interface->sptr_neighbor->address,
                                            OSPF_HOST_NET_MASK, OSPF_ROUTER_LINK_TYPE_STUB_NETWORK, 0x00, sptr_interface->cost,
                                            &(sptr_router_link_advertisement->number_of_links), sptr_length);
                                        }
                                    }
                                break;
                            case 2:
                                /* RFC 2178 G.6 */
                                sptr_link = ospf_add_a_link_description_to_the_router_advertisement (sptr_link,
                                    (sptr_interface->address & sptr_interface->netmask), sptr_interface->netmask, OSPF_ROUTER_LINK_TYPE_STUB_NETWORK, 0x00,
                                    sptr_interface->cost, &(sptr_router_link_advertisement->number_of_links), sptr_length);
                                    break;
                            default:
                                break;
                            }
#else /* __RFC_2328__ */
                        if (sptr_interface->sptr_neighbor != NULL)
                            {
                            if (sptr_interface->sptr_neighbor->address != 0x00000000L)                  /* Option 1 */
                                {
                                sptr_link = ospf_add_a_link_description_to_the_router_advertisement (sptr_link, sptr_interface->sptr_neighbor->address,
                                    OSPF_HOST_NET_MASK, OSPF_ROUTER_LINK_TYPE_STUB_NETWORK, 0x00, sptr_interface->cost,
                                    &(sptr_router_link_advertisement->number_of_links), sptr_length);
                                }
                            }
#endif /* __RFC_2328__ */
#endif /* __UNNUMBERED_LINK__ */
                        break;
                        }

                    case OSPF_BROADCAST:                                                                /* section 12.4.1.2 (page 120-121) */
                    case OSPF_NBMA:
                        {
                        if ((sptr_interface->state != OSPF_INTERFACE_WAITING) && (sptr_interface->designated_router.address != 0x00000000L) &&
                            (((sptr_interface->state != OSPF_INTERFACE_DESIGNATED_ROUTER) && (sptr_interface->designated_router.state == OSPF_NEIGHBOR_FULL)) ||
                            ((sptr_interface->state == OSPF_INTERFACE_DESIGNATED_ROUTER) && (sptr_interface->number_of_neighbors_in_full_state > 0x0000))))
                            {
                            /* section 12.4.1.2, second bullet item, except for last sentence (page 120) */

                            sptr_link = ospf_add_a_link_description_to_the_router_advertisement (sptr_link, sptr_interface->designated_router.address,
                                sptr_interface->address, OSPF_ROUTER_LINK_TYPE_TRANSIT_NETWORK, 0x00, sptr_interface->cost,
                                &(sptr_router_link_advertisement->number_of_links), sptr_length);
                            }
                        else
                            {
                            /* section 12.4.1.2, first bullet item and last sentence of second bullet item (page 120-121) */

                            sptr_link = ospf_add_a_link_description_to_the_router_advertisement (sptr_link,
                                (sptr_interface->address & sptr_interface->netmask), sptr_interface->netmask, OSPF_ROUTER_LINK_TYPE_STUB_NETWORK, 0x00,
                                sptr_interface->cost, &(sptr_router_link_advertisement->number_of_links), sptr_length);
                            }

                        break;
                        }

                    case OSPF_VIRTUAL_LINK:                                                     /* section 12.4.1.3 (page 121) */
                        {
                        if (sptr_interface->sptr_neighbor != NULL)
                            {
                            if (sptr_interface->sptr_neighbor->state == OSPF_NEIGHBOR_FULL)
                                {
                                sptr_link = ospf_add_a_link_description_to_the_router_advertisement (sptr_link, sptr_interface->sptr_neighbor->id,
                                sptr_interface->address, OSPF_ROUTER_LINK_TYPE_VIRTUAL, 0x00,
                                sptr_interface->cost, &(sptr_router_link_advertisement->number_of_links), sptr_length);
                                }
                            }
                        break;
                        }

                    case OSPF_POINT_TO_MULTIPOINT:                                              /* section 12.4.1.4 (page 121) */
                        {
                        sptr_link = ospf_add_a_link_description_to_the_router_advertisement (sptr_link,
                            sptr_interface->address, OSPF_HOST_NET_MASK, OSPF_ROUTER_LINK_TYPE_STUB_NETWORK, 0x00, 0x0000,
                            &(sptr_router_link_advertisement->number_of_links), sptr_length);

                        for (sptr_neighbor = sptr_interface->sptr_neighbor; sptr_neighbor != NULL;
                            sptr_neighbor = sptr_next_neighbor)
                            {
                            sptr_next_neighbor = sptr_neighbor->sptr_forward_link;
                            if (sptr_neighbor->state == OSPF_NEIGHBOR_FULL)
                                {
                                sptr_link = ospf_add_a_link_description_to_the_router_advertisement (sptr_link, sptr_neighbor->id,
                                    sptr_interface->address, OSPF_ROUTER_LINK_TYPE_PPP, 0x00, sptr_interface->cost,
                                    &(sptr_router_link_advertisement->number_of_links), sptr_length);
                                }
                            }

                        break;
                        }

                    default:
                        {
                        break;
                        }
                    }
                }
            }
        }

        return;
}
/**************************************************************************************************************************************/
static OSPF_ROUTER_LINK_PIECE *ospf_add_a_link_description_to_the_router_advertisement (OSPF_ROUTER_LINK_PIECE *sptr_link,
    ULONG link_id,ULONG link_data,BYTE_ENUM (OSPF_ROUTER_LINK_TYPE) type,BYTE number_of_metrics,USHORT tos0_metric,
    USHORT *sptr_number_of_links,USHORT *sptr_length)
{
    OSPF_PRINTF_DEBUG (OSPF_DEBUG_PRINTF, "OSPF: Entering ospf_add_a_link_description_to_the_router_advertisement\r\n");

    sptr_link->link_id = link_id;
    sptr_link->link_id = host_to_net_long (sptr_link->link_id);

    sptr_link->link_data = link_data;
    sptr_link->link_data = host_to_net_long (sptr_link->link_data);

    sptr_link->type = type;
    sptr_link->number_of_metrics = number_of_metrics;

    sptr_link->tos0_metric = tos0_metric;
    sptr_link->tos0_metric = host_to_net_short (sptr_link->tos0_metric);

    ++(*sptr_number_of_links);
    *sptr_length += OSPF_ROUTER_LINK_PIECE_SIZE;

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

    return (sptr_link);
}
/*******************************************************************************************************//* section 12.4.2 (page 124) */
void ospf_originate_network_links_advertisement (OSPF_INTERFACE *sptr_interface)
{
    OSPF_NETWORK_LINK_ADVERTISEMENT_HEADER *sptr_network_link_advertisement;
    UNION_OSPF_LINK_STATE_ADVERTISEMENT *sptr_advertisement;
    OSPF_NETWORK_LINK_PIECE *sptr_link;
    OSPF_NEIGHBOR *sptr_neighbor = NULL;
    OSPF_NEIGHBOR *sptr_next_neighbor = NULL;
    USHORT length;
    USHORT allocated_size_for_lsa;
    OSPF_LS_DATABASE_ENTRY *sptr_database_entry;
    bool is_neighbor_full = FALSE;

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

    /* Originate only if the Designated Router is fully adjacent to at least one other router on the network */
    if (sptr_interface != NULL)
        {
        for (sptr_neighbor = sptr_interface->sptr_neighbor; sptr_neighbor != NULL;  sptr_neighbor = sptr_next_neighbor)
            {
            sptr_next_neighbor = sptr_neighbor->sptr_forward_link;
            if (sptr_neighbor->state == OSPF_NEIGHBOR_FULL)
                {
                is_neighbor_full = TRUE;
                break;
                }
            }
        }

    if (is_neighbor_full == FALSE)
        {
        return;
        }


    sptr_network_link_advertisement = (OSPF_NETWORK_LINK_ADVERTISEMENT_HEADER *) create_buffer_for_lsa (sptr_interface, &allocated_size_for_lsa);

    if (sptr_network_link_advertisement == NULL)
        {
        ospf_print_memory_error_message_and_free_buffer_if_necessary ((void *) NULL, "OSPF_NETWORK_LINK_ADVERTISEMENT_HEADER");
        return;
        }

    sptr_network_link_advertisement->ls_header.age = 0x0000;

    if ((sptr_interface->sptr_area->area_id == 0x00000000L || sptr_interface->sptr_area->flags._bit.stub != TRUE) &&
        (sptr_interface->sptr_area->area_id == 0x00000000L || sptr_interface->sptr_area->flags._bit.nssa != TRUE))
        {
        sptr_network_link_advertisement->ls_header.options._byte = OSPF_ENABLE_EXTERNAL_ROUTING;
        }
    else
        {
        sptr_network_link_advertisement->ls_header.options._byte = OSPF_NOT_ENABLE_EXTERNAL_ROUTING;

        if (sptr_interface->sptr_area->flags._bit.nssa == TRUE)
            {
            sptr_network_link_advertisement->ls_header.options._bit.nssa = TRUE;
            }
        }

    sptr_network_link_advertisement->ls_header.type = OSPF_LS_NETWORK;

    sptr_network_link_advertisement->ls_header.id = sptr_interface->designated_router.address;
    sptr_network_link_advertisement->ls_header.id = host_to_net_long (sptr_network_link_advertisement->ls_header.id);

    sptr_network_link_advertisement->ls_header.advertising_router = ospf.router_id;
    sptr_network_link_advertisement->ls_header.advertising_router =
        host_to_net_long (sptr_network_link_advertisement->ls_header.advertising_router);

    sptr_network_link_advertisement->network_mask = sptr_interface->netmask;
    sptr_network_link_advertisement->network_mask = host_to_net_long (sptr_network_link_advertisement->network_mask);

    sptr_link = &(sptr_network_link_advertisement->attached_router);