bgpd/bgp_attr.h

   1 /* BGP attributes.
   2    Copyright (C) 1996, 97, 98 Kunihiro Ishiguro
   3
   4 This file is part of GNU Zebra.
   5
   6 GNU Zebra is free software; you can redistribute it and/or modify it
   7 under the terms of the GNU General Public License as published by the
   8 Free Software Foundation; either version 2, or (at your option) any
   9 later version.
  10
  11 GNU Zebra is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Zebra; see the file COPYING.  If not, write to the Free
  18 Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  19 02111-1307, USA.  */
  20
  21 #ifndef _QUAGGA_BGP_ATTR_H
  22 #define _QUAGGA_BGP_ATTR_H
  23
  24 /* Simple bit mapping. */
  25 #define BITMAP_NBBY 8
  26
  27 #define SET_BITMAP(MAP, NUM) \
  28         SET_FLAG (MAP[(NUM) / BITMAP_NBBY], 1 << ((NUM) % BITMAP_NBBY))
  29
  30 #define CHECK_BITMAP(MAP, NUM) \
  31         CHECK_FLAG (MAP[(NUM) / BITMAP_NBBY], 1 << ((NUM) % BITMAP_NBBY))
  32
  33 #define BGP_MED_MAX UINT32_MAX
  34
  35
  36 /* BGP Attribute type range. */
  37 #define BGP_ATTR_TYPE_RANGE     256
  38 #define BGP_ATTR_BITMAP_SIZE    (BGP_ATTR_TYPE_RANGE / BITMAP_NBBY)
  39
  40 /* BGP Attribute flags. */
  41 #define BGP_ATTR_FLAG_OPTIONAL  0x80    /* Attribute is optional. */
  42 #define BGP_ATTR_FLAG_TRANS     0x40    /* Attribute is transitive. */
  43 #define BGP_ATTR_FLAG_PARTIAL   0x20    /* Attribute is partial. */
  44 #define BGP_ATTR_FLAG_EXTLEN    0x10    /* Extended length flag. */
  45
  46 /* BGP attribute header must bigger than 2. */
  47 #define BGP_ATTR_MIN_LEN        3       /* Attribute flag, type length. */
  48 #define BGP_ATTR_DEFAULT_WEIGHT 32768
  49
  50 /* Additional/uncommon BGP attributes.
  51  * lazily allocated as and when a struct attr
  52  * requires it.
  53  */
  54 struct attr_extra
  55 {
  56   /* Multi-Protocol Nexthop, AFI IPv6 */
  57 #ifdef HAVE_IPV6
  58   struct in6_addr mp_nexthop_global;
  59   struct in6_addr mp_nexthop_local;
  60 #endif /* HAVE_IPV6 */
  61
  62   /* Extended Communities attribute. */
  63   struct ecommunity *ecommunity;
  64
  65   /* Route-Reflector Cluster attribute */
  66   struct cluster_list *cluster;
  67
  68   /* Unknown transitive attribute. */
  69   struct transit *transit;
  70
  71   struct in_addr mp_nexthop_global_in;
  72   struct in_addr mp_nexthop_local_in;
  73
  74   /* Aggregator Router ID attribute */
  75   struct in_addr aggregator_addr;
  76
  77   /* Route Reflector Originator attribute */
  78   struct in_addr originator_id;
  79
  80   /* Local weight, not actually an attribute */
  81   u_int32_t weight;
  82
  83   /* Aggregator ASN */
  84   as_t aggregator_as;
  85
  86   /* MP Nexthop length */
  87   u_char mp_nexthop_len;
  88 };
  89
  90 /* BGP core attribute structure. */
  91 struct attr
  92 {
  93   /* AS Path structure */
  94   struct aspath *aspath;
  95
  96   /* Community structure */
  97   struct community *community;
  98
  99   /* Lazily allocated pointer to extra attributes */
 100   struct attr_extra *extra;
 101
 102   /* Reference count of this attribute. */
 103   unsigned long refcnt;
 104
 105   /* Flag of attribute is set or not. */
 106   u_int32_t flag;
 107
 108   /* Apart from in6_addr, the remaining static attributes */
 109   struct in_addr nexthop;
 110   u_int32_t med;
 111   u_int32_t local_pref;
 112
 113   /* AS-Pathlimit */
 114   struct {
 115     u_int32_t as;
 116     u_char ttl;
 117   } pathlimit;
 118
 119   /* Path origin attribute */
 120   u_char origin;
 121 };
 122
 123 /* Router Reflector related structure. */
 124 struct cluster_list
 125 {
 126   unsigned long refcnt;
 127   int length;
 128   struct in_addr *list;
 129 };
 130
 131 /* Unknown transit attribute. */
 132 struct transit
 133 {
 134   unsigned long refcnt;
 135   int length;
 136   u_char *val;
 137 };
 138
 139 #define ATTR_FLAG_BIT(X)  (1 << ((X) - 1))
 140
 141 /* Prototypes. */
 142 extern void bgp_attr_init (void);
 143 extern void bgp_attr_finish (void);
 144 extern int bgp_attr_parse (struct peer *, struct attr *, bgp_size_t,
 145                     struct bgp_nlri *, struct bgp_nlri *);
 146 extern int bgp_attr_check (struct peer *, struct attr *);
 147 extern struct attr_extra *bgp_attr_extra_get (struct attr *);
 148 extern void bgp_attr_extra_free (struct attr *);
 149 extern void bgp_attr_dup (struct attr *, struct attr *);
 150 extern struct attr *bgp_attr_intern (struct attr *attr);
 151 extern void bgp_attr_unintern (struct attr *);
 152 extern void bgp_attr_flush (struct attr *);
 153 extern struct attr *bgp_attr_default_set (struct attr *attr, u_char);
 154 extern struct attr *bgp_attr_default_intern (u_char);
 155 extern struct attr *bgp_attr_aggregate_intern (struct bgp *, u_char,
 156                                         struct aspath *,
 157                                         struct community *, int as_set);
 158 extern bgp_size_t bgp_packet_attribute (struct bgp *bgp, struct peer *,
 159                                  struct stream *, struct attr *,
 160                                  struct prefix *, afi_t, safi_t,
 161                                  struct peer *, struct prefix_rd *, u_char *);
 162 extern bgp_size_t bgp_packet_withdraw (struct peer *peer, struct stream *s,
 163                                 struct prefix *p, afi_t, safi_t,
 164                                 struct prefix_rd *, u_char *);
 165 extern void bgp_dump_routes_attr (struct stream *, struct attr *,
 166                                   struct prefix *);
 167 extern int attrhash_cmp (const void *, const void *);
 168 extern unsigned int attrhash_key_make (void *);
 169 extern void attr_show_all (struct vty *);
 170 extern unsigned long int attr_count (void);
 171 extern unsigned long int attr_unknown_count (void);
 172
 173 /* Cluster list prototypes. */
 174 extern int cluster_loop_check (struct cluster_list *, struct in_addr);
 175 extern void cluster_unintern (struct cluster_list *);
 176
 177 /* Transit attribute prototypes. */
 178 void transit_unintern (struct transit *);
 179
 180 /* Exported for unit-test purposes only */
 181 extern int bgp_mp_reach_parse (struct peer *, bgp_size_t, struct attr *,
 182                                struct bgp_nlri *);
 183 extern int bgp_mp_unreach_parse (struct peer *, bgp_size_t, struct bgp_nlri *);
 184
 185 #endif /* _QUAGGA_BGP_ATTR_H */