bgpd/bgp_advertise.c

   1 /* BGP advertisement and adjacency
   2  * Copyright (C) 1996, 97, 98, 99, 2000 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 along
  17  * with this program; see the file COPYING; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #include <zebra.h>
  22
  23 #include "command.h"
  24 #include "memory.h"
  25 #include "prefix.h"
  26 #include "hash.h"
  27 #include "thread.h"
  28 #include "queue.h"
  29 #include "filter.h"
  30
  31 #include "bgpd/bgpd.h"
  32 #include "bgpd/bgp_table.h"
  33 #include "bgpd/bgp_route.h"
  34 #include "bgpd/bgp_advertise.h"
  35 #include "bgpd/bgp_attr.h"
  36 #include "bgpd/bgp_debug.h"
  37 #include "bgpd/bgp_aspath.h"
  38 #include "bgpd/bgp_packet.h"
  39 #include "bgpd/bgp_fsm.h"
  40 #include "bgpd/bgp_mplsvpn.h"
  41 #include "bgpd/bgp_updgrp.h"
  42
  43 /* BGP advertise attribute is used for pack same attribute update into
  44    one packet.  To do that we maintain attribute hash in struct
  45    peer.  */
  46 struct bgp_advertise_attr *baa_new(void)
  47 {
  48         return XCALLOC(MTYPE_BGP_ADVERTISE_ATTR,
  49                        sizeof(struct bgp_advertise_attr));
  50 }
  51
  52 static void baa_free(struct bgp_advertise_attr *baa)
  53 {
  54         XFREE(MTYPE_BGP_ADVERTISE_ATTR, baa);
  55 }
  56
  57 static void *baa_hash_alloc(void *p)
  58 {
  59         struct bgp_advertise_attr *ref = (struct bgp_advertise_attr *)p;
  60         struct bgp_advertise_attr *baa;
  61
  62         baa = baa_new();
  63         baa->attr = ref->attr;
  64         return baa;
  65 }
  66
  67 unsigned int baa_hash_key(const void *p)
  68 {
  69         const struct bgp_advertise_attr *baa = p;
  70
  71         return attrhash_key_make(baa->attr);
  72 }
  73
  74 bool baa_hash_cmp(const void *p1, const void *p2)
  75 {
  76         const struct bgp_advertise_attr *baa1 = p1;
  77         const struct bgp_advertise_attr *baa2 = p2;
  78
  79         return attrhash_cmp(baa1->attr, baa2->attr);
  80 }
  81
  82 /* BGP update and withdraw information is stored in BGP advertise
  83    structure.  This structure is referred from BGP adjacency
  84    information.  */
  85 struct bgp_advertise *bgp_advertise_new(void)
  86 {
  87         return XCALLOC(MTYPE_BGP_ADVERTISE, sizeof(struct bgp_advertise));
  88 }
  89
  90 void bgp_advertise_free(struct bgp_advertise *adv)
  91 {
  92         if (adv->pathi)
  93                 /* bgp_advertise bgp_path_info reference */
  94                 bgp_path_info_unlock(adv->pathi);
  95         XFREE(MTYPE_BGP_ADVERTISE, adv);
  96 }
  97
  98 void bgp_advertise_add(struct bgp_advertise_attr *baa,
  99                        struct bgp_advertise *adv)
 100 {
 101         adv->next = baa->adv;
 102         if (baa->adv)
 103                 baa->adv->prev = adv;
 104         baa->adv = adv;
 105 }
 106
 107 void bgp_advertise_delete(struct bgp_advertise_attr *baa,
 108                           struct bgp_advertise *adv)
 109 {
 110         if (adv->next)
 111                 adv->next->prev = adv->prev;
 112         if (adv->prev)
 113                 adv->prev->next = adv->next;
 114         else
 115                 baa->adv = adv->next;
 116 }
 117
 118 struct bgp_advertise_attr *bgp_advertise_intern(struct hash *hash,
 119                                                 struct attr *attr)
 120 {
 121         struct bgp_advertise_attr ref;
 122         struct bgp_advertise_attr *baa;
 123
 124         ref.attr = bgp_attr_intern(attr);
 125         baa = (struct bgp_advertise_attr *)hash_get(hash, &ref, baa_hash_alloc);
 126         baa->refcnt++;
 127
 128         return baa;
 129 }
 130
 131 void bgp_advertise_unintern(struct hash *hash, struct bgp_advertise_attr *baa)
 132 {
 133         if (baa->refcnt)
 134                 baa->refcnt--;
 135
 136         if (baa->refcnt && baa->attr)
 137                 bgp_attr_unintern(&baa->attr);
 138         else {
 139                 if (baa->attr) {
 140                         hash_release(hash, baa);
 141                         bgp_attr_unintern(&baa->attr);
 142                 }
 143                 baa_free(baa);
 144         }
 145 }
 146
 147 int bgp_adj_out_lookup(struct peer *peer, struct bgp_node *rn,
 148                        uint32_t addpath_tx_id)
 149 {
 150         struct bgp_adj_out *adj;
 151         struct peer_af *paf;
 152         afi_t afi;
 153         safi_t safi;
 154         int addpath_capable;
 155
 156         RB_FOREACH (adj, bgp_adj_out_rb, &rn->adj_out)
 157                 SUBGRP_FOREACH_PEER (adj->subgroup, paf)
 158                         if (paf->peer == peer) {
 159                                 afi = SUBGRP_AFI(adj->subgroup);
 160                                 safi = SUBGRP_SAFI(adj->subgroup);
 161                                 addpath_capable =
 162                                         bgp_addpath_encode_tx(peer, afi, safi);
 163
 164                                 /* Match on a specific addpath_tx_id if we are
 165                                  * using addpath for
 166                                  * this
 167                                  * peer and if an addpath_tx_id was specified */
 168                                 if (addpath_capable && addpath_tx_id
 169                                     && adj->addpath_tx_id != addpath_tx_id)
 170                                         continue;
 171
 172                                 return (adj->adv ? (adj->adv->baa ? 1 : 0)
 173                                                  : (adj->attr ? 1 : 0));
 174                         }
 175
 176         return 0;
 177 }
 178
 179
 180 void bgp_adj_in_set(struct bgp_node *rn, struct peer *peer, struct attr *attr,
 181                     uint32_t addpath_id)
 182 {
 183         struct bgp_adj_in *adj;
 184
 185         for (adj = rn->adj_in; adj; adj = adj->next) {
 186                 if (adj->peer == peer && adj->addpath_rx_id == addpath_id) {
 187                         if (adj->attr != attr) {
 188                                 bgp_attr_unintern(&adj->attr);
 189                                 adj->attr = bgp_attr_intern(attr);
 190                         }
 191                         return;
 192                 }
 193         }
 194         adj = XCALLOC(MTYPE_BGP_ADJ_IN, sizeof(struct bgp_adj_in));
 195         adj->peer = peer_lock(peer); /* adj_in peer reference */
 196         adj->attr = bgp_attr_intern(attr);
 197         adj->addpath_rx_id = addpath_id;
 198         BGP_ADJ_IN_ADD(rn, adj);
 199         bgp_lock_node(rn);
 200 }
 201
 202 void bgp_adj_in_remove(struct bgp_node *rn, struct bgp_adj_in *bai)
 203 {
 204         bgp_attr_unintern(&bai->attr);
 205         BGP_ADJ_IN_DEL(rn, bai);
 206         peer_unlock(bai->peer); /* adj_in peer reference */
 207         XFREE(MTYPE_BGP_ADJ_IN, bai);
 208 }
 209
 210 int bgp_adj_in_unset(struct bgp_node *rn, struct peer *peer,
 211                      uint32_t addpath_id)
 212 {
 213         struct bgp_adj_in *adj;
 214         struct bgp_adj_in *adj_next;
 215
 216         adj = rn->adj_in;
 217
 218         if (!adj)
 219                 return 0;
 220
 221         while (adj) {
 222                 adj_next = adj->next;
 223
 224                 if (adj->peer == peer && adj->addpath_rx_id == addpath_id) {
 225                         bgp_adj_in_remove(rn, adj);
 226                         bgp_unlock_node(rn);
 227                 }
 228
 229                 adj = adj_next;
 230         }
 231
 232         return 1;
 233 }
 234
 235 void bgp_sync_init(struct peer *peer)
 236 {
 237         afi_t afi;
 238         safi_t safi;
 239         struct bgp_synchronize *sync;
 240
 241         FOREACH_AFI_SAFI (afi, safi) {
 242                 sync = XCALLOC(MTYPE_BGP_SYNCHRONISE,
 243                                sizeof(struct bgp_synchronize));
 244                 bgp_adv_fifo_init(&sync->update);
 245                 bgp_adv_fifo_init(&sync->withdraw);
 246                 bgp_adv_fifo_init(&sync->withdraw_low);
 247                 peer->sync[afi][safi] = sync;
 248         }
 249 }
 250
 251 void bgp_sync_delete(struct peer *peer)
 252 {
 253         afi_t afi;
 254         safi_t safi;
 255
 256         FOREACH_AFI_SAFI (afi, safi) {
 257                 XFREE(MTYPE_BGP_SYNCHRONISE, peer->sync[afi][safi]);
 258                 peer->sync[afi][safi] = NULL;
 259         }
 260 }