bgpd/bgp_mac.c

   1 /*
   2  * BGPd - Mac hash code
   3  * Copyright (C) 2018 Cumulus Networks, Inc.
   4  *               Donald Sharp
   5  *
   6  * This program 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 Free
   8  * Software Foundation; either version 2 of the License, or (at your option)
   9  * any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  14  * 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 #include <zebra.h>
  21
  22 #include <jhash.h>
  23 #include <hash.h>
  24 #include <prefix.h>
  25 #include <memory.h>
  26
  27 #include "bgpd/bgpd.h"
  28 #include "bgpd/bgp_mac.h"
  29 #include "bgpd/bgp_memory.h"
  30 #include "bgpd/bgp_route.h"
  31 #include "bgpd/bgp_packet.h"
  32 #include "bgpd/bgp_rd.h"
  33 #include "bgpd/bgp_debug.h"
  34 #include "bgpd/bgp_evpn_private.h"
  35
  36 DEFINE_MTYPE_STATIC(BGPD, BSM, "Mac Hash Entry");
  37 DEFINE_MTYPE_STATIC(BGPD, BSM_STRING, "Mac Hash Entry Interface String");
  38
  39 struct bgp_self_mac {
  40         struct ethaddr macaddr;
  41         struct list *ifp_list;
  42 };
  43
  44 static unsigned int bgp_mac_hash_key_make(const void *data)
  45 {
  46         const struct bgp_self_mac *bsm = data;
  47
  48         return jhash(&bsm->macaddr, ETH_ALEN, 0xa5a5dead);
  49 }
  50
  51 static bool bgp_mac_hash_cmp(const void *d1, const void *d2)
  52 {
  53         const struct bgp_self_mac *bsm1 = d1;
  54         const struct bgp_self_mac *bsm2 = d2;
  55
  56         if (memcmp(&bsm1->macaddr, &bsm2->macaddr, ETH_ALEN) == 0)
  57                 return true;
  58
  59         return false;
  60 }
  61
  62 void bgp_mac_init(void)
  63 {
  64         bm->self_mac_hash = hash_create(bgp_mac_hash_key_make, bgp_mac_hash_cmp,
  65                                         "BGP MAC Hash");
  66 }
  67
  68 static void bgp_mac_hash_free(void *data)
  69 {
  70         struct bgp_self_mac *bsm = data;
  71
  72         if (bsm->ifp_list)
  73                 list_delete(&bsm->ifp_list);
  74
  75         XFREE(MTYPE_BSM, bsm);
  76 }
  77
  78 void bgp_mac_finish(void)
  79 {
  80         hash_clean(bm->self_mac_hash, bgp_mac_hash_free);
  81         hash_free(bm->self_mac_hash);
  82 }
  83
  84 static void bgp_mac_hash_interface_string_del(void *val)
  85 {
  86         char *data = val;
  87
  88         XFREE(MTYPE_BSM_STRING, data);
  89 }
  90
  91 static void *bgp_mac_hash_alloc(void *p)
  92 {
  93         const struct bgp_self_mac *orig = p;
  94         struct bgp_self_mac *bsm;
  95
  96         bsm = XCALLOC(MTYPE_BSM, sizeof(struct bgp_self_mac));
  97         memcpy(&bsm->macaddr, &orig->macaddr, ETH_ALEN);
  98
  99         bsm->ifp_list = list_new();
 100         bsm->ifp_list->del = bgp_mac_hash_interface_string_del;
 101
 102         return bsm;
 103 }
 104
 105 struct bgp_mac_find_internal {
 106         struct bgp_self_mac *bsm;
 107         const char *ifname;
 108 };
 109
 110 static void bgp_mac_find_ifp_internal(struct hash_bucket *bucket, void *arg)
 111 {
 112         struct bgp_mac_find_internal *bmfi = arg;
 113         struct bgp_self_mac *bsm = bucket->data;
 114         struct listnode *node;
 115         char *name;
 116
 117         for (ALL_LIST_ELEMENTS_RO(bsm->ifp_list, node, name)) {
 118                 if (strcmp(name, bmfi->ifname) == 0) {
 119                         bmfi->bsm = bsm;
 120                         return;
 121                 }
 122         }
 123 }
 124
 125 static struct bgp_self_mac *bgp_mac_find_interface_name(const char *ifname)
 126 {
 127         struct bgp_mac_find_internal bmfi;
 128
 129         bmfi.bsm = NULL;
 130         bmfi.ifname = ifname;
 131         hash_iterate(bm->self_mac_hash, bgp_mac_find_ifp_internal, &bmfi);
 132
 133         return bmfi.bsm;
 134 }
 135
 136 static void bgp_process_mac_rescan_table(struct bgp *bgp, struct peer *peer,
 137                                          struct bgp_table *table,
 138                                          struct ethaddr *macaddr)
 139 {
 140         struct bgp_node *prn, *rn;
 141         struct bgp_path_info *pi;
 142
 143         for (prn = bgp_table_top(table); prn; prn = bgp_route_next(prn)) {
 144                 struct bgp_table *sub = prn->info;
 145
 146                 if (!sub)
 147                         continue;
 148
 149                 for (rn = bgp_table_top(sub); rn; rn = bgp_route_next(rn)) {
 150                         bool rn_affected;
 151                         struct prefix_evpn *pevpn = (struct prefix_evpn *)&rn->p;
 152                         struct prefix_rd prd;
 153                         uint32_t num_labels = 0;
 154                         mpls_label_t *label_pnt = NULL;
 155                         struct bgp_route_evpn evpn;
 156
 157                         if (pevpn->family == AF_EVPN &&
 158                             pevpn->prefix.route_type == BGP_EVPN_MAC_IP_ROUTE &&
 159                             memcmp(&rn->p.u.prefix_evpn.macip_addr.mac,
 160                                    macaddr, ETH_ALEN) == 0)
 161                                 rn_affected = true;
 162                         else
 163                                 rn_affected = false;
 164
 165                         for (pi = rn->info; pi; pi = pi->next) {
 166                                 if (pi->peer == peer)
 167                                         break;
 168                         }
 169
 170                         if (!pi)
 171                                 continue;
 172
 173                         /*
 174                          * If the mac address is not the same then
 175                          * we don't care and since we are looking
 176                          */
 177                         if ((memcmp(&pi->attr->rmac, macaddr, ETH_ALEN) != 0) &&
 178                             !rn_affected)
 179                                 continue;
 180
 181                         if (pi->extra)
 182                                 num_labels = pi->extra->num_labels;
 183                         if (num_labels)
 184                                 label_pnt = &pi->extra->label[0];
 185
 186                         prd.family = AF_UNSPEC;
 187                         prd.prefixlen = 64;
 188                         memcpy(&prd.val, &prn->p.u.val, 8);
 189
 190                         if (CHECK_FLAG(pi->flags, BGP_PATH_REMOVED)) {
 191                                 if (bgp_debug_update(peer, &rn->p, NULL, 1)) {
 192                                         char pfx_buf[BGP_PRD_PATH_STRLEN];
 193
 194                                         bgp_debug_rdpfxpath2str(
 195                                                 AFI_L2VPN, SAFI_EVPN, &prd,
 196                                                 &rn->p, label_pnt, num_labels,
 197                                                 pi->addpath_rx_id ? 1 : 0,
 198                                                 pi->addpath_rx_id, pfx_buf,
 199                                                 sizeof(pfx_buf));
 200                                         zlog_debug(
 201                                                    "%s skip update of %s marked as removed",
 202                                                    peer->host, pfx_buf);
 203                                 }
 204                                 continue;
 205                         }
 206
 207                         memcpy(&evpn, &pi->attr->evpn_overlay, sizeof(evpn));
 208                         int32_t ret = bgp_update(peer, &rn->p,
 209                                                  pi->addpath_rx_id,
 210                                                  pi->attr, AFI_L2VPN, SAFI_EVPN,
 211                                                  ZEBRA_ROUTE_BGP,
 212                                                  BGP_ROUTE_NORMAL, &prd,
 213                                                  label_pnt, num_labels,
 214                                                  1, &evpn);
 215
 216                         if (ret < 0)
 217                                 bgp_unlock_node(rn);
 218                 }
 219         }
 220 }
 221
 222 static void bgp_mac_rescan_evpn_table(struct bgp *bgp, struct ethaddr *macaddr)
 223 {
 224         struct listnode *node;
 225         struct peer *peer;
 226         safi_t safi;
 227         afi_t afi;
 228
 229         afi = AFI_L2VPN;
 230         safi = SAFI_EVPN;
 231         for (ALL_LIST_ELEMENTS_RO(bgp->peer, node, peer)) {
 232
 233                 if (CHECK_FLAG(peer->sflags, PEER_STATUS_GROUP))
 234                         continue;
 235
 236                 if (peer->status != Established)
 237                         continue;
 238
 239                 if (CHECK_FLAG(peer->af_flags[afi][safi],
 240                                PEER_FLAG_SOFT_RECONFIG)) {
 241                         if (bgp_debug_update(peer, NULL, NULL, 1))
 242                                 zlog_debug("Processing EVPN MAC interface change on peer %s (inbound, soft-reconfig)",
 243                                            peer->host);
 244
 245                         bgp_soft_reconfig_in(peer, afi, safi);
 246                 } else {
 247                         struct bgp_table *table = bgp->rib[afi][safi];
 248
 249                         if (bgp_debug_update(peer, NULL, NULL, 1))
 250                                 zlog_debug("Processing EVPN MAC interface change on peer %s",
 251                                            peer->host);
 252                         bgp_process_mac_rescan_table(bgp, peer, table, macaddr);
 253                 }
 254         }
 255 }
 256
 257 static void bgp_mac_rescan_all_evpn_tables(struct ethaddr *macaddr)
 258 {
 259         struct listnode *node;
 260         struct bgp *bgp;
 261
 262         for (ALL_LIST_ELEMENTS_RO(bm->bgp, node, bgp)) {
 263                 struct bgp_table *table = bgp->rib[AFI_L2VPN][SAFI_EVPN];
 264
 265                 if (table)
 266                         bgp_mac_rescan_evpn_table(bgp, macaddr);
 267         }
 268 }
 269
 270 static void bgp_mac_remove_ifp_internal(struct bgp_self_mac *bsm, char *ifname,
 271                                         struct ethaddr *macaddr)
 272 {
 273         struct listnode *node = NULL;
 274         char *name;
 275
 276         for (ALL_LIST_ELEMENTS_RO(bsm->ifp_list, node, name)) {
 277                 if (strcmp(name, ifname) == 0)
 278                         break;
 279         }
 280
 281         if (node) {
 282                 list_delete_node(bsm->ifp_list, node);
 283                 XFREE(MTYPE_BSM_STRING, name);
 284         }
 285
 286         if (bsm->ifp_list->count == 0) {
 287                 struct ethaddr mac = *macaddr;
 288
 289                 hash_release(bm->self_mac_hash, bsm);
 290                 list_delete(&bsm->ifp_list);
 291                 XFREE(MTYPE_BSM, bsm);
 292
 293                 bgp_mac_rescan_all_evpn_tables(&mac);
 294         }
 295 }
 296
 297 void bgp_mac_add_mac_entry(struct interface *ifp)
 298 {
 299         struct bgp_self_mac lookup;
 300         struct bgp_self_mac *bsm;
 301         struct bgp_self_mac *old_bsm;
 302         char *ifname;
 303
 304         memcpy(&lookup.macaddr, &ifp->hw_addr, ETH_ALEN);
 305         bsm = hash_get(bm->self_mac_hash, &lookup, bgp_mac_hash_alloc);
 306
 307         /*
 308          * Does this happen to be a move
 309          */
 310         old_bsm = bgp_mac_find_interface_name(ifp->name);
 311         ifname = XSTRDUP(MTYPE_BSM_STRING, ifp->name);
 312
 313         if (bsm->ifp_list->count == 0) {
 314
 315                 listnode_add(bsm->ifp_list, ifname);
 316                 if (old_bsm)
 317                         bgp_mac_remove_ifp_internal(old_bsm, ifname,
 318                                                     &old_bsm->macaddr);
 319         } else {
 320                 /*
 321                  * If old mac address is the same as the new,
 322                  * then there is nothing to do here
 323                  */
 324                 if (old_bsm == bsm) {
 325                         XFREE(MTYPE_BSM_STRING, ifname);
 326                         return;
 327                 }
 328
 329                 if (old_bsm)
 330                         bgp_mac_remove_ifp_internal(old_bsm, ifp->name,
 331                                                     &old_bsm->macaddr);
 332
 333                 listnode_add(bsm->ifp_list, ifname);
 334         }
 335
 336         bgp_mac_rescan_all_evpn_tables(&bsm->macaddr);
 337 }
 338
 339 void bgp_mac_del_mac_entry(struct interface *ifp)
 340 {
 341         struct bgp_self_mac lookup;
 342         struct bgp_self_mac *bsm;
 343
 344         memcpy(&lookup.macaddr, &ifp->hw_addr, ETH_ALEN);
 345         bsm = hash_lookup(bm->self_mac_hash, &lookup);
 346         if (!bsm)
 347                 return;
 348
 349         /*
 350          * Write code to allow old mac address to no-longer
 351          * win if we happen to have received it from a peer.
 352          */
 353         bgp_mac_remove_ifp_internal(bsm, ifp->name, &bsm->macaddr);
 354 }
 355
 356 /* This API checks MAC address against any of local
 357  * assigned (SVIs) MAC address.
 358  * An example: router-mac attribute in any of evpn update
 359  * requires to compare against local mac.
 360  */
 361 bool bgp_mac_exist(struct ethaddr *mac)
 362 {
 363         struct bgp_self_mac lookup;
 364         struct bgp_self_mac *bsm;
 365         static uint8_t tmp [ETHER_ADDR_STRLEN] = {0};
 366
 367         if (memcmp(mac, &tmp, ETH_ALEN) == 0)
 368                 return false;
 369
 370         memcpy(&lookup.macaddr, mac, ETH_ALEN);
 371         bsm = hash_lookup(bm->self_mac_hash, &lookup);
 372         if (!bsm)
 373                 return false;
 374
 375         return true;
 376 }
 377
 378 /* This API checks EVPN type-2 prefix and comapares
 379  * mac against any of local assigned (SVIs) MAC
 380  * address.
 381  */
 382 bool bgp_mac_entry_exists(struct prefix *p)
 383 {
 384         struct prefix_evpn *pevpn = (struct prefix_evpn *)p;
 385
 386         if (pevpn->family != AF_EVPN)
 387                 return false;
 388
 389         if (pevpn->prefix.route_type != BGP_EVPN_MAC_IP_ROUTE)
 390                 return false;
 391
 392         return bgp_mac_exist(&p->u.prefix_evpn.macip_addr.mac);
 393
 394         return true;
 395 }
 396
 397 static void bgp_mac_show_mac_entry(struct hash_bucket *bucket, void *arg)
 398 {
 399         struct vty *vty = arg;
 400         struct bgp_self_mac *bsm = bucket->data;
 401         struct listnode *node;
 402         char *name;
 403         char buf_mac[ETHER_ADDR_STRLEN];
 404
 405         vty_out(vty, "Mac Address: %s ",
 406                 prefix_mac2str(&bsm->macaddr, buf_mac, sizeof(buf_mac)));
 407
 408         for (ALL_LIST_ELEMENTS_RO(bsm->ifp_list, node, name))
 409                 vty_out(vty, "%s ", name);
 410
 411         vty_out(vty, "\n");
 412 }
 413
 414 void bgp_mac_dump_table(struct vty *vty)
 415 {
 416         hash_iterate(bm->self_mac_hash, bgp_mac_show_mac_entry, vty);
 417 }