ospf6_abr.c

linux 路由软件 可支持RIP OSPF BGP等

      OSPF6_ABR_SUMMARY_METRIC_SET (router_lsa, route->path.cost);
      router_lsa->router_id = ADV_ROUTER_IN_PREFIX (&route->prefix);
      type = htons (OSPF6_LSTYPE_INTER_ROUTER);
    }
  else
    {
      prefix_lsa = (struct ospf6_inter_prefix_lsa *)
        ((caddr_t) lsa_header + sizeof (struct ospf6_lsa_header));
      p = (caddr_t) prefix_lsa + sizeof (struct ospf6_inter_prefix_lsa);

      /* Fill Inter-Area-Prefix-LSA */
      OSPF6_ABR_SUMMARY_METRIC_SET (prefix_lsa, route->path.cost);
      prefix_lsa->prefix.prefix_length = route->prefix.prefixlen;
      prefix_lsa->prefix.prefix_options = route->path.prefix_options;

      /* set Prefix */
      memcpy (p, &route->prefix.u.prefix6,
              OSPF6_PREFIX_SPACE (route->prefix.prefixlen));
      ospf6_prefix_apply_mask (&prefix_lsa->prefix);
      p += OSPF6_PREFIX_SPACE (route->prefix.prefixlen);
      type = htons (OSPF6_LSTYPE_INTER_PREFIX);
    }

  /* Fill LSA Header */
  lsa_header->age = 0;
  lsa_header->type = type;
  lsa_header->id = summary->path.origin.id;
  lsa_header->adv_router = area->ospf6->router_id;
  lsa_header->seqnum =
    ospf6_new_ls_seqnum (lsa_header->type, lsa_header->id,
                         lsa_header->adv_router, area->lsdb);
  lsa_header->length = htons ((caddr_t) p - (caddr_t) lsa_header);

  /* LSA checksum */
  ospf6_lsa_checksum (lsa_header);

  /* create LSA */
  lsa = ospf6_lsa_create (lsa_header);

  /* Originate */
  ospf6_lsa_originate_area (lsa, area);
}

void
ospf6_abr_range_update (struct ospf6_route *range)
{
  u_int32_t cost = 0;
  struct ospf6_route *ro;

  assert (range->type == OSPF6_DEST_TYPE_RANGE);

  /* update range's cost and active flag */
  for (ro = ospf6_route_match_head (&range->prefix, ospf6->route_table);
       ro; ro = ospf6_route_match_next (&range->prefix, ro))
    {
      if (ro->path.area_id == range->path.area_id &&
          ! CHECK_FLAG (ro->flag, OSPF6_ROUTE_REMOVE))
        cost = MAX (cost, ro->path.cost);
    }

  if (range->path.cost != cost)
    {
      range->path.cost = cost;

      if (range->path.cost)
        SET_FLAG (range->flag, OSPF6_ROUTE_ACTIVE_SUMMARY);
      else
        UNSET_FLAG (range->flag, OSPF6_ROUTE_ACTIVE_SUMMARY);

      ospf6_abr_originate_summary (range);
    }
}

void
ospf6_abr_originate_summary (struct ospf6_route *route)
{
  listnode node;
  struct ospf6_area *oa;
  struct ospf6_route *range = NULL;

  if (route->type == OSPF6_DEST_TYPE_NETWORK)
    {
      oa = ospf6_area_lookup (route->path.area_id, ospf6);
      range = ospf6_route_lookup_bestmatch (&route->prefix, oa->range_table);
      if (range)
        ospf6_abr_range_update (range);
    }

  for (node = listhead (ospf6->area_list); node; nextnode (node))
    {
      oa = (struct ospf6_area *) getdata (node);
      ospf6_abr_originate_summary_to_area (route, oa);
    }
}

/* RFC 2328 16.2. Calculating the inter-area routes */
void
ospf6_abr_examin_summary (struct ospf6_lsa *lsa, struct ospf6_area *oa)
{
  struct prefix prefix, abr_prefix;
  struct ospf6_route_table *table = NULL;
  struct ospf6_route *range, *route, *old = NULL;
  struct ospf6_route *abr_entry;
  u_char type = 0;
  char options[3] = {0, 0, 0};
  u_int8_t prefix_options = 0;
  u_int32_t cost = 0;
  u_char router_bits = 0;
  int i;
  char buf[64];
  int is_debug = 0;

  if (lsa->header->type == htons (OSPF6_LSTYPE_INTER_PREFIX))
    {
      struct ospf6_inter_prefix_lsa *prefix_lsa;

      if (IS_OSPF6_DEBUG_EXAMIN (INTER_PREFIX))
        {
          is_debug++;
          zlog_info ("Examin %s in area %s", lsa->name, oa->name);
        }

      prefix_lsa = (struct ospf6_inter_prefix_lsa *)
        OSPF6_LSA_HEADER_END (lsa->header);
      prefix.family = AF_INET6;
      prefix.prefixlen = prefix_lsa->prefix.prefix_length;
      ospf6_prefix_in6_addr (&prefix.u.prefix6, &prefix_lsa->prefix);
      prefix2str (&prefix, buf, sizeof (buf));
      table = oa->ospf6->route_table;
      type = OSPF6_DEST_TYPE_NETWORK;
      prefix_options = prefix_lsa->prefix.prefix_options;
      cost = OSPF6_ABR_SUMMARY_METRIC (prefix_lsa);
    }
  else if (lsa->header->type == htons (OSPF6_LSTYPE_INTER_ROUTER))
    {
      struct ospf6_inter_router_lsa *router_lsa;

      if (IS_OSPF6_DEBUG_EXAMIN (INTER_ROUTER))
        {
          is_debug++;
          zlog_info ("Examin %s in area %s", lsa->name, oa->name);
        }

      router_lsa = (struct ospf6_inter_router_lsa *)
        OSPF6_LSA_HEADER_END (lsa->header);
      ospf6_linkstate_prefix (router_lsa->router_id, htonl (0), &prefix);
      inet_ntop (AF_INET, &router_lsa->router_id, buf, sizeof (buf));
      table = oa->ospf6->brouter_table;
      type = OSPF6_DEST_TYPE_ROUTER;
      options[0] = router_lsa->options[0];
      options[1] = router_lsa->options[1];
      options[2] = router_lsa->options[2];
      cost = OSPF6_ABR_SUMMARY_METRIC (router_lsa);
      SET_FLAG (router_bits, OSPF6_ROUTER_BIT_E);
    }
  else
    assert (0);

  /* Find existing route */
  route = ospf6_route_lookup (&prefix, table);
  if (route)
    ospf6_route_lock (route);
  while (route && ospf6_route_is_prefix (&prefix, route))
    {
      if (route->path.area_id == oa->area_id &&
          route->path.origin.type == lsa->header->type &&
          route->path.origin.id == lsa->header->id &&
          route->path.origin.adv_router == lsa->header->adv_router)
        old = route;
      route = ospf6_route_next (route);
    }

  /* (1) if cost == LSInfinity or if the LSA is MaxAge */
  if (cost == LS_INFINITY)
    {
      if (is_debug)
        zlog_info ("cost is LS_INFINITY, ignore");
      if (old)
        ospf6_route_remove (old, table);
      return;
    }
  if (OSPF6_LSA_IS_MAXAGE (lsa))
    {
      if (is_debug)
        zlog_info ("LSA is MaxAge, ignore");
      if (old)
        ospf6_route_remove (old, table);
      return;
    }

  /* (2) if the LSA is self-originated, ignore */
  if (lsa->header->adv_router == oa->ospf6->router_id)
    {
      if (is_debug)
        zlog_info ("LSA is self-originated, ignore");
      if (old)
        ospf6_route_remove (old, table);
      return;
    }

  /* (3) if the prefix is equal to an active configured address range */
  if (lsa->header->type == htons (OSPF6_LSTYPE_INTER_PREFIX))
    {
      range = ospf6_route_lookup (&prefix, oa->range_table);
      if (range)
        {
          if (is_debug)
            zlog_info ("Prefix is equal to address range, ignore");
          if (old)
            ospf6_route_remove (old, table);
          return;
        }
    }

  /* (4) if the routing table entry for the ABR does not exist */
  ospf6_linkstate_prefix (lsa->header->adv_router, htonl (0), &abr_prefix);
  abr_entry = ospf6_route_lookup (&abr_prefix, oa->ospf6->brouter_table);
  if (abr_entry == NULL || abr_entry->path.area_id != oa->area_id ||
      CHECK_FLAG (abr_entry->flag, OSPF6_ROUTE_REMOVE) ||
      ! CHECK_FLAG (abr_entry->path.router_bits, OSPF6_ROUTER_BIT_B))
    {
      if (is_debug)
        zlog_info ("ABR router entry does not exist, ignore");
      if (old)
        ospf6_route_remove (old, table);
      return;
    }

  /* (5),(6),(7) the path preference is handled by the sorting
     in the routing table. Always install the path by substituting
     old route (if any). */
  if (old)
    route = ospf6_route_copy (old);
  else
    route = ospf6_route_create ();

  route->type = type;
  route->prefix = prefix;
  route->path.origin.type = lsa->header->type;
  route->path.origin.id = lsa->header->id;
  route->path.origin.adv_router = lsa->header->adv_router;
  route->path.router_bits = router_bits;
  route->path.options[0] = options[0];
  route->path.options[1] = options[1];
  route->path.options[2] = options[2];
  route->path.prefix_options = prefix_options;
  route->path.area_id = oa->area_id;
  route->path.type = OSPF6_PATH_TYPE_INTER;
  route->path.cost = abr_entry->path.cost + cost;
  for (i = 0; i < OSPF6_MULTI_PATH_LIMIT; i++)
    route->nexthop[i] = abr_entry->nexthop[i];

  if (is_debug)
    zlog_info ("Install route: %s", buf);
  ospf6_route_add (route, table);
}

void
ospf6_abr_examin_brouter (u_int32_t router_id)
{
  struct ospf6_lsa *lsa;
  struct ospf6_area *oa;
  listnode node;
  u_int16_t type;

  type = htons (OSPF6_LSTYPE_INTER_ROUTER);
  for (node = listhead (ospf6->area_list); node; nextnode (node))
    {
      oa = OSPF6_AREA (getdata (node));
      for (lsa = ospf6_lsdb_type_router_head (type, router_id, oa->lsdb); lsa;
           lsa = ospf6_lsdb_type_router_next (type, router_id, lsa))
        ospf6_abr_examin_summary (lsa, oa);
    }

  type = htons (OSPF6_LSTYPE_INTER_PREFIX);
  for (node = listhead (ospf6->area_list); node; nextnode (node))
    {
      oa = OSPF6_AREA (getdata (node));
      for (lsa = ospf6_lsdb_type_router_head (type, router_id, oa->lsdb); lsa;
           lsa = ospf6_lsdb_type_router_next (type, router_id, lsa))
        ospf6_abr_examin_summary (lsa, oa);
    }
}


/* Display functions */
int
ospf6_inter_area_prefix_lsa_show (struct vty *vty, struct ospf6_lsa *lsa)
{
  struct ospf6_inter_prefix_lsa *prefix_lsa;
  struct in6_addr in6;
  char buf[64];

  prefix_lsa = (struct ospf6_inter_prefix_lsa *)
    OSPF6_LSA_HEADER_END (lsa->header);

  vty_out (vty, "     Metric: %lu%s",
           (u_long) OSPF6_ABR_SUMMARY_METRIC (prefix_lsa), VNL);

  ospf6_prefix_options_printbuf (prefix_lsa->prefix.prefix_options,
                                 buf, sizeof (buf));
  vty_out (vty, "     Prefix Options: %s%s", buf, VNL);

  ospf6_prefix_in6_addr (&in6, &prefix_lsa->prefix);
  inet_ntop (AF_INET6, &in6, buf, sizeof (buf));
  vty_out (vty, "     Prefix: %s/%d%s", buf,
           prefix_lsa->prefix.prefix_length, VNL);

  return 0;
}

int
ospf6_inter_area_router_lsa_show (struct vty *vty, struct ospf6_lsa *lsa)
{
  struct ospf6_inter_router_lsa *router_lsa;
  char buf[64];

  router_lsa = (struct ospf6_inter_router_lsa *)
    OSPF6_LSA_HEADER_END (lsa->header);

  ospf6_options_printbuf (router_lsa->options, buf, sizeof (buf));
  vty_out (vty, "     Options: %s%s", buf, VNL);
  vty_out (vty, "     Metric: %lu%s",
           (u_long) OSPF6_ABR_SUMMARY_METRIC (router_lsa), VNL);
  inet_ntop (AF_INET, &router_lsa->router_id, buf, sizeof (buf));
  vty_out (vty, "     Destination Router ID: %s%s", buf, VNL);

  return 0;
}

/* Debug commands */
DEFUN (debug_ospf6_abr,
       debug_ospf6_abr_cmd,
       "debug ospf6 abr",
       DEBUG_STR
       OSPF6_STR
       "Debug OSPFv3 ABR function\n"
      )
{
  OSPF6_DEBUG_ABR_ON ();
  return CMD_SUCCESS;
}

DEFUN (no_debug_ospf6_abr,
       no_debug_ospf6_abr_cmd,
       "no debug ospf6 abr",
       NO_STR
       DEBUG_STR
       OSPF6_STR
       "Debug OSPFv3 ABR function\n"
      )
{
  OSPF6_DEBUG_ABR_OFF ();
  return CMD_SUCCESS;
}

int
config_write_ospf6_debug_abr (struct vty *vty)
{
  if (IS_OSPF6_DEBUG_ABR)
    vty_out (vty, "debug ospf6 abr%s", VNL);
  return 0;
}

void
install_element_ospf6_debug_abr ()
{
  install_element (ENABLE_NODE, &debug_ospf6_abr_cmd);
  install_element (ENABLE_NODE, &no_debug_ospf6_abr_cmd);
  install_element (CONFIG_NODE, &debug_ospf6_abr_cmd);
  install_element (CONFIG_NODE, &no_debug_ospf6_abr_cmd);
}

struct ospf6_lsa_handler inter_prefix_handler =
{
  OSPF6_LSTYPE_INTER_PREFIX,
  "Inter-Prefix",
  ospf6_inter_area_prefix_lsa_show
};

struct ospf6_lsa_handler inter_router_handler =
{
  OSPF6_LSTYPE_INTER_ROUTER,
  "Inter-Router",
  ospf6_inter_area_router_lsa_show
};

void
ospf6_abr_init ()
{
  ospf6_install_lsa_handler (&inter_prefix_handler);
  ospf6_install_lsa_handler (&inter_router_handler);
}