zebra_rib.c

zebra测试源代码用于 SOCKET 通信

  /* Process this route node. */
  rib_process (rn, same);

  /* Free implicit route.*/
  if (same)
    newrib_free (same);

  return 0;
}

int
rib_delete_ipv4 (int type, int flags, struct prefix_ipv4 *p,
		 struct in_addr *gate, unsigned int ifindex, u_int32_t vrf_id)
{
  struct route_table *table;
  struct route_node *rn;
  struct rib *rib;
  struct rib *fib = NULL;
  struct rib *same = NULL;
  struct nexthop *nexthop;
  char buf1[BUFSIZ];
  char buf2[BUFSIZ];

  /* Lookup table.  */
  table = vrf_table (AFI_IP, SAFI_UNICAST, 0);
  if (! table)
    return 0;

  /* Apply mask. */
  apply_mask_ipv4 (p);

  /* Lookup route node. */
  rn = route_node_lookup (table, (struct prefix *) p);
  if (! rn)
    {
      if (IS_ZEBRA_DEBUG_KERNEL)
	{
	  if (gate)
	    zlog_info ("route %s/%d via %s ifindex %d doesn't exist in rib",
		       inet_ntop (AF_INET, &p->prefix, buf1, BUFSIZ),
		       p->prefixlen,
		       inet_ntop (AF_INET, gate, buf2, BUFSIZ),
		       ifindex);
	  else
	    zlog_info ("route %s/%d ifindex %d doesn't exist in rib",
		       inet_ntop (AF_INET, &p->prefix, buf1, BUFSIZ),
		       p->prefixlen,
		       ifindex);
	}
      return ZEBRA_ERR_RTNOEXIST;
    }

  /* Lookup same type route. */
  for (rib = rn->info; rib; rib = rib->next)
    {
      if (CHECK_FLAG (rib->flags, ZEBRA_FLAG_SELECTED))
	fib = rib;

      if (rib->type == ZEBRA_ROUTE_CONNECT)
	{
	  nexthop = rib->nexthop;

	  if (rib->type == type
	      && nexthop && nexthop->type == NEXTHOP_TYPE_IFINDEX
	      && nexthop->ifindex == ifindex)
	    {
	      if (rib->refcnt)
		{
		  rib->refcnt--;
		  route_unlock_node (rn);
		  route_unlock_node (rn);
		  return 0;
		}
	      same = rib;
	      break;
	    }
	}
      else
	{
	  if (rib->type == type)
	    {
	      same = rib;
	      break;
	    }
	}
    }

  /* If same type of route can't be found and this message is from
     kernel. */
  if (! same)
    {
      if (fib && type == ZEBRA_ROUTE_KERNEL)
	{
	  /* Unset flags. */
	  for (nexthop = fib->nexthop; nexthop; nexthop = nexthop->next)
	    UNSET_FLAG (nexthop->flags, NEXTHOP_FLAG_FIB);

	  UNSET_FLAG (fib->flags, ZEBRA_FLAG_SELECTED);
	}
      else
	{
	  if (IS_ZEBRA_DEBUG_KERNEL)
	    {
	      if (gate)
		zlog_info ("route %s/%d via %s ifindex %d type %d doesn't exist in rib",
			   inet_ntop (AF_INET, &p->prefix, buf1, BUFSIZ),
			   p->prefixlen,
			   inet_ntop (AF_INET, gate, buf2, BUFSIZ),
			   ifindex,
			   type);
	      else
		zlog_info ("route %s/%d ifindex %d type %d doesn't exist in rib",
			   inet_ntop (AF_INET, &p->prefix, buf1, BUFSIZ),
			   p->prefixlen,
			   ifindex,
			   type);
	    }
	  route_unlock_node (rn);
	  return ZEBRA_ERR_RTNOEXIST;
	}
    }

  if (same)
    rib_delnode (rn, same);

  /* Process changes. */
  rib_process (rn, same);

  if (same)
    {
      newrib_free (same);
      route_unlock_node (rn);
    }

  route_unlock_node (rn);

  return 0;
}

/* Install static route into rib. */
void
static_install_ipv4 (struct prefix *p, struct static_ipv4 *si)
{
  struct rib *rib;
  struct route_node *rn;
  struct route_table *table;

  /* Lookup table.  */
  table = vrf_table (AFI_IP, SAFI_UNICAST, 0);
  if (! table)
    return;

  /* Lookup existing route */
  rn = route_node_get (table, p);
  for (rib = rn->info; rib; rib = rib->next)
    if (rib->type == ZEBRA_ROUTE_STATIC && rib->distance == si->distance)
      break;

  if (rib)
    {
      /* Same distance static route is there.  Update it with new
         nexthop. */
      rib_uninstall (rn, rib);
      route_unlock_node (rn);

      switch (si->type)
	{
	case STATIC_IPV4_GATEWAY:
	  nexthop_ipv4_add (rib, &si->gate.ipv4);
	  break;
	case STATIC_IPV4_IFNAME:
	  nexthop_ifname_add (rib, si->gate.ifname);
	  break;
	case STATIC_IPV4_BLACKHOLE:
	  nexthop_blackhole_add (rib);
	  break;
	}
      rib_process (rn, NULL);
    }
  else
    {
      /* This is new static route. */
      rib = XMALLOC (MTYPE_RIB, sizeof (struct rib));
      memset (rib, 0, sizeof (struct rib));

      rib->type = ZEBRA_ROUTE_STATIC;
      rib->distance = si->distance;
      rib->metric = 0;
      rib->nexthop_num = 0;

      switch (si->type)
	{
	case STATIC_IPV4_GATEWAY:
	  nexthop_ipv4_add (rib, &si->gate.ipv4);
	  break;
	case STATIC_IPV4_IFNAME:
	  nexthop_ifname_add (rib, si->gate.ifname);
	  break;
	case STATIC_IPV4_BLACKHOLE:
	  nexthop_blackhole_add (rib);
	  break;
	}

      /* Link this rib to the tree. */
      rib_addnode (rn, rib);

      /* Process this prefix. */
      rib_process (rn, NULL);
    }
}

int
static_ipv4_nexthop_same (struct nexthop *nexthop, struct static_ipv4 *si)
{
  if (nexthop->type == NEXTHOP_TYPE_IPV4
      && si->type == STATIC_IPV4_GATEWAY
      && IPV4_ADDR_SAME (&nexthop->gate.ipv4, &si->gate.ipv4))
    return 1;
  if (nexthop->type == NEXTHOP_TYPE_IFNAME
      && si->type == STATIC_IPV4_IFNAME
      && strcmp (nexthop->ifname, si->gate.ifname) == 0)
    return 1;
  if (nexthop->type == NEXTHOP_TYPE_BLACKHOLE
      && si->type == STATIC_IPV4_BLACKHOLE)
    return 1;
  return 0;;
}

/* Uninstall static route from RIB. */
void
static_uninstall_ipv4 (struct prefix *p, struct static_ipv4 *si)
{
  struct route_node *rn;
  struct rib *rib;
  struct nexthop *nexthop;
  struct route_table *table;

  /* Lookup table.  */
  table = vrf_table (AFI_IP, SAFI_UNICAST, 0);
  if (! table)
    return;

  /* Lookup existing route with type and distance. */
  rn = route_node_lookup (table, p);
  if (! rn)
    return;

  for (rib = rn->info; rib; rib = rib->next)
    if (rib->type == ZEBRA_ROUTE_STATIC && rib->distance == si->distance)
      break;

  if (! rib)
    {
      route_unlock_node (rn);
      return;
    }

  /* Lookup nexthop. */
  for (nexthop = rib->nexthop; nexthop; nexthop = nexthop->next)
    if (static_ipv4_nexthop_same (nexthop, si))
      break;

  /* Can't find nexthop. */
  if (! nexthop)
    {
      route_unlock_node (rn);
      return;
    }
  
  /* Check nexthop. */
  if (rib->nexthop_num == 1)
    {
      rib_delnode (rn, rib);
      rib_process (rn, rib);
      newrib_free (rib);
      route_unlock_node (rn);
    }
  else
    {
      rib_uninstall (rn, rib);
      nexthop_delete (rib, nexthop);
      nexthop_free (nexthop);
      rib_process (rn, rib);
    }

  /* Unlock node. */
  route_unlock_node (rn);
}

/* Add static route into static route configuration. */
int
static_add_ipv4 (struct prefix *p, struct in_addr *gate, char *ifname,
		 u_char distance, u_int32_t vrf_id)
{
  u_char type = 0;
  struct route_node *rn;
  struct static_ipv4 *si;
  struct static_ipv4 *pp;
  struct static_ipv4 *cp;
  struct static_ipv4 *update = NULL;
  struct route_table *stable;

  /* Lookup table.  */
  stable = vrf_static_table (AFI_IP, SAFI_UNICAST, vrf_id);
  if (! stable)
    return -1;
  
  /* Lookup static route prefix. */
  rn = route_node_get (stable, p);

  /* Make flags. */
  if (gate)
    type = STATIC_IPV4_GATEWAY;
  else if (ifname)
    type = STATIC_IPV4_IFNAME;
  else
    type = STATIC_IPV4_BLACKHOLE;

  /* Do nothing if there is a same static route.  */
  for (si = rn->info; si; si = si->next)
    {
      if (type == si->type
	  && (! gate || IPV4_ADDR_SAME (gate, &si->gate.ipv4))
	  && (! ifname || strcmp (ifname, si->gate.ifname) == 0))
	{
	  if (distance == si->distance)
	    {
	      route_unlock_node (rn);
	      return 0;
	    }
	  else
	    update = si;
	}
    }

  /* Distance chaged.  */
  if (update)
    static_delete_ipv4 (p, gate, ifname, update->distance, vrf_id);

  /* Make new static route structure. */
  si = XMALLOC (MTYPE_STATIC_IPV4, sizeof (struct static_ipv4));
  memset (si, 0, sizeof (struct static_ipv4));

  si->type = type;
  si->distance = distance;

  if (gate)
    si->gate.ipv4 = *gate;
  if (ifname)
    si->gate.ifname = XSTRDUP (0, ifname);

  /* Add new static route information to the tree with sort by
     distance value and gateway address. */
  for (pp = NULL, cp = rn->info; cp; pp = cp, cp = cp->next)
    {
      if (si->distance < cp->distance)
	break;
      if (si->distance > cp->distance)
	continue;
      if (si->type == STATIC_IPV4_GATEWAY && cp->type == STATIC_IPV4_GATEWAY)
	{
	  if (ntohl (si->gate.ipv4.s_addr) < ntohl (cp->gate.ipv4.s_addr))
	    break;
	  if (ntohl (si->gate.ipv4.s_addr) > ntohl (cp->gate.ipv4.s_addr))
	    continue;
	}
    }

  /* Make linked list. */
  if (pp)
    pp->next = si;
  else
    rn->info = si;
  if (cp)
    cp->prev = si;
  si->prev = pp;
  si->next = cp;

  /* Install into rib. */
  static_install_ipv4 (p, si);

  return 1;
}

/* Delete static route from static route configuration. */
int
static_delete_ipv4 (struct prefix *p, struct in_addr *gate, char *ifname,
		    u_char distance, u_int32_t vrf_id)
{
  u_char type = 0;
  struct route_node *rn;
  struct static_ipv4 *si;
  struct route_table *stable;

  /* Lookup table.  */
  stable = vrf_static_table (AFI_IP, SAFI_UNICAST, vrf_id);
  if (! stable)
    return -1;

  /* Lookup static route prefix. */
  rn = route_node_lookup (stable, p);
  if (! rn)
    return 0;

  /* Make flags. */
  if (gate)
    type = STATIC_IPV4_GATEWAY;
  else if (ifname)
    type = STATIC_IPV4_IFNAME;
  else
    type = STATIC_IPV4_BLACKHOLE;

  /* Find same static route is the tree */
  for (si = rn->info; si; si = si->next)
    if (type == si->type
	&& (! gate || IPV4_ADDR_SAME (gate, &si->gate.ipv4))
	&& (! ifname || strcmp (ifname, si->gate.ifname) == 0))
      break;

  /* Can't find static route. */
  if (! si)
    {
      route_unlock_node (rn);
      return 0;
    }

  /* Install into rib. */
  static_uninstall_ipv4 (p, si);

  /* Unlink static route from linked list. */
  if (si->prev)
    si->prev->next = si->next;
  else
    rn->info = si->next;
  if (si->next)
    si->next->prev = si->prev;
  
  /* Free static route configuration. */
  XFREE (MTYPE_STATIC_IPV4, si);

  return 1;
}


#ifdef HAVE_IPV6
int
rib_bogus_ipv6 (int type, struct prefix_ipv6 *p,
		struct in6_addr *gate, unsigned int ifindex, int table)
{
  if (type == ZEBRA_ROUTE_CONNECT && IN6_IS_ADDR_UNSPECIFIED (&p->prefix))
    return 1;
  if (type == ZEBRA_ROUTE_KERNEL && IN6_IS_ADDR_UNSPECIFIED (&p->prefix)
      && p->prefixlen == 96 && gate && IN6_IS_ADDR_UNSPECIFIED (gate))
    {
      kernel_delete_ipv6_old (p, gate, ifindex, 0, table);
      return 1;
    }
  return 0;
}

int
rib_add_ipv6 (int type, int flags, struct prefix_ipv6 *p,
	      struct in6_addr *gate, unsigned int ifindex, u_int32_t vrf_id)
{
  struct rib *rib;
  struct rib *same = NULL;
  struct route_table *table;
  struct route_node *rn;
  struct nexthop *nexthop;

  int distance;
  u_int32_t metric = 0;

  /* Lookup table.  */
  table = vrf_table (AFI_IP6, SAFI_UNICAST, 0);
  if (! table)
    return 0;

  /* Make sure mask is applied. */
  apply_mask_ipv6 (p);

  /* Set default distance by route type. */
  distance = route_info[type].distance;
  
  if (type == ZEBRA_ROUTE_BGP && CHECK_FLAG (flags, ZEBRA_FLAG_IBGP))
    distance = 200;

  /* Filter bogus route. */
  if (rib_bogus_ipv6 (type, p, gate, ifindex, 0))
    return 0;

  /* Lookup route node.*/
  rn = route_node_get (table, (struct prefix *) p);

  /* If same type of route are installed, treat it as a implicit
     withdraw. */
  for (rib = rn->info; rib; rib = rib->next)
    {
      if (rib->type == ZEBRA_ROUTE_CONNECT)
	{
	  nexthop = rib->nexthop;

	  if (rib->type == type
	      && nexthop && nexthop->type == NEXTHOP_TYPE_IFINDEX
	      && nexthop->ifindex == ifindex)
	  {
	    rib->refcnt++;
	    return 0;
	  }
	}
      else if (rib->type == type)
	{
	  same = rib;
	  rib_delnode (rn, same);
	  route_unlock_node (rn);
	  break;
	}
    }

  /* Allocate new rib structure. */
  rib = XMALLOC (MTYPE_RIB, sizeof (struct rib));
  memset (rib, 0, sizeof (struct rib));
  rib->type = type;
  rib->distance = distance;
  rib->flags = flags;
  rib->metric = metric;
  rib->nexthop_num = 0;
  rib->uptime = time (NULL);

  /* Nexthop settings. */
  if (gate)
    {
      if (ifindex)
	nexthop_ipv6_ifindex_add (rib, gate, ifindex);
      else
	nexthop_ipv6_add (rib, gate);
    }
  else
    nexthop_ifindex_add (rib, ifindex);

  /* If this route is kernel route, set FIB flag to the route. */
  if (type == ZEBRA_ROUTE_KERNEL || type == ZEBRA_ROUTE_CONNECT)
    for (nexthop = rib->nexthop; nexthop; nexthop = nexthop->next)
      SET_FLAG (nexthop->flags, NEXTHOP_FLAG_FIB);

  /* Link new rib to node.*/
  rib_addnode (rn, rib);

  /* Process this route node. */
  rib_process (rn, same);