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 Intf 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_dest *pdest, *dest;
 141         struct bgp_path_info *pi;
 142
 143         for (pdest = bgp_table_top(table); pdest;
 144              pdest = bgp_route_next(pdest)) {
 145                 struct bgp_table *sub = pdest->info;
 146                 const struct prefix *pdest_p = bgp_dest_get_prefix(pdest);
 147
 148                 if (!sub)
 149                         continue;
 150
 151                 for (dest = bgp_table_top(sub); dest;
 152                      dest = bgp_route_next(dest)) {
 153                         bool dest_affected;
 154                         const struct prefix *p = bgp_dest_get_prefix(dest);
 155                         struct prefix_evpn *pevpn = (struct prefix_evpn *)dest;
 156                         struct prefix_rd prd;
 157                         uint32_t num_labels = 0;
 158                         mpls_label_t *label_pnt = NULL;
 159                         struct bgp_route_evpn evpn;
 160
 161                         if (pevpn->family == AF_EVPN
 162                             && pevpn->prefix.route_type == BGP_EVPN_MAC_IP_ROUTE
 163                             && memcmp(&p->u.prefix_evpn.macip_addr.mac, macaddr,
 164                                       ETH_ALEN)
 165                                        == 0)
 166                                 dest_affected = true;
 167                         else
 168                                 dest_affected = false;
 169
 170                         for (pi = dest->info; pi; pi = pi->next) {
 171                                 if (pi->peer == peer)
 172                                         break;
 173                         }
 174
 175                         if (!pi)
 176                                 continue;
 177
 178                         /*
 179                          * If the mac address is not the same then
 180                          * we don't care and since we are looking
 181                          */
 182                         if ((memcmp(&pi->attr->rmac, macaddr, ETH_ALEN) != 0)
 183                             && !dest_affected)
 184                                 continue;
 185
 186                         if (pi->extra)
 187                                 num_labels = pi->extra->num_labels;
 188                         if (num_labels)
 189                                 label_pnt = &pi->extra->label[0];
 190
 191                         prd.family = AF_UNSPEC;
 192                         prd.prefixlen = 64;
 193                         memcpy(&prd.val, pdest_p->u.val, 8);
 194
 195                         if (CHECK_FLAG(pi->flags, BGP_PATH_REMOVED)) {
 196                                 if (bgp_debug_update(peer, p, NULL, 1)) {
 197                                         char pfx_buf[BGP_PRD_PATH_STRLEN];
 198
 199                                         bgp_debug_rdpfxpath2str(
 200                                                 AFI_L2VPN, SAFI_EVPN, &prd,
 201                                                 p, label_pnt, num_labels,
 202                                                 pi->addpath_rx_id ? 1 : 0,
 203                                                 pi->addpath_rx_id, pfx_buf,
 204                                                 sizeof(pfx_buf));
 205                                         zlog_debug(
 206                                                    "%s skip update of %s marked as removed",
 207                                                    peer->host, pfx_buf);
 208                                 }
 209                                 continue;
 210                         }
 211
 212                         memcpy(&evpn, &pi->attr->evpn_overlay, sizeof(evpn));
 213                         int32_t ret = bgp_update(peer, p,
 214                                                  pi->addpath_rx_id,
 215                                                  pi->attr, AFI_L2VPN, SAFI_EVPN,
 216                                                  ZEBRA_ROUTE_BGP,
 217                                                  BGP_ROUTE_NORMAL, &prd,
 218                                                  label_pnt, num_labels,
 219                                                  1, &evpn);
 220
 221                         if (ret < 0)
 222                                 bgp_dest_unlock_node(dest);
 223                 }
 224         }
 225 }
 226
 227 static void bgp_mac_rescan_evpn_table(struct bgp *bgp, struct ethaddr *macaddr)
 228 {
 229         struct listnode *node;
 230         struct peer *peer;
 231         safi_t safi;
 232         afi_t afi;
 233
 234         afi = AFI_L2VPN;
 235         safi = SAFI_EVPN;
 236         for (ALL_LIST_ELEMENTS_RO(bgp->peer, node, peer)) {
 237
 238                 if (CHECK_FLAG(peer->sflags, PEER_STATUS_GROUP))
 239                         continue;
 240
 241                 if (peer->status != Established)
 242                         continue;
 243
 244                 if (CHECK_FLAG(peer->af_flags[afi][safi],
 245                                PEER_FLAG_SOFT_RECONFIG)) {
 246                         if (bgp_debug_update(peer, NULL, NULL, 1))
 247                                 zlog_debug("Processing EVPN MAC interface change on peer %s (inbound, soft-reconfig)",
 248                                            peer->host);
 249
 250                         bgp_soft_reconfig_in(peer, afi, safi);
 251                 } else {
 252                         struct bgp_table *table = bgp->rib[afi][safi];
 253
 254                         if (bgp_debug_update(peer, NULL, NULL, 1))
 255                                 zlog_debug("Processing EVPN MAC interface change on peer %s",
 256                                            peer->host);
 257                         bgp_process_mac_rescan_table(bgp, peer, table, macaddr);
 258                 }
 259         }
 260 }
 261
 262 static void bgp_mac_rescan_all_evpn_tables(struct ethaddr *macaddr)
 263 {
 264         struct listnode *node;
 265         struct bgp *bgp;
 266
 267         for (ALL_LIST_ELEMENTS_RO(bm->bgp, node, bgp)) {
 268                 struct bgp_table *table = bgp->rib[AFI_L2VPN][SAFI_EVPN];
 269
 270                 if (table)
 271                         bgp_mac_rescan_evpn_table(bgp, macaddr);
 272         }
 273 }
 274
 275 static void bgp_mac_remove_ifp_internal(struct bgp_self_mac *bsm, char *ifname,
 276                                         struct ethaddr *macaddr)
 277 {
 278         struct listnode *node = NULL;
 279         char *name;
 280
 281         for (ALL_LIST_ELEMENTS_RO(bsm->ifp_list, node, name)) {
 282                 if (strcmp(name, ifname) == 0)
 283                         break;
 284         }
 285
 286         if (node) {
 287                 list_delete_node(bsm->ifp_list, node);
 288                 XFREE(MTYPE_BSM_STRING, name);
 289         }
 290
 291         if (bsm->ifp_list->count == 0) {
 292                 struct ethaddr mac = *macaddr;
 293
 294                 hash_release(bm->self_mac_hash, bsm);
 295                 list_delete(&bsm->ifp_list);
 296                 XFREE(MTYPE_BSM, bsm);
 297
 298                 bgp_mac_rescan_all_evpn_tables(&mac);
 299         }
 300 }
 301
 302 void bgp_mac_add_mac_entry(struct interface *ifp)
 303 {
 304         struct bgp_self_mac lookup;
 305         struct bgp_self_mac *bsm;
 306         struct bgp_self_mac *old_bsm;
 307         char *ifname;
 308
 309         memcpy(&lookup.macaddr, &ifp->hw_addr, ETH_ALEN);
 310         bsm = hash_get(bm->self_mac_hash, &lookup, bgp_mac_hash_alloc);
 311
 312         /*
 313          * Does this happen to be a move
 314          */
 315         old_bsm = bgp_mac_find_interface_name(ifp->name);
 316         ifname = XSTRDUP(MTYPE_BSM_STRING, ifp->name);
 317
 318         if (bsm->ifp_list->count == 0) {
 319
 320                 listnode_add(bsm->ifp_list, ifname);
 321                 if (old_bsm)
 322                         bgp_mac_remove_ifp_internal(old_bsm, ifname,
 323                                                     &old_bsm->macaddr);
 324         } else {
 325                 /*
 326                  * If old mac address is the same as the new,
 327                  * then there is nothing to do here
 328                  */
 329                 if (old_bsm == bsm) {
 330                         XFREE(MTYPE_BSM_STRING, ifname);
 331                         return;
 332                 }
 333
 334                 if (old_bsm)
 335                         bgp_mac_remove_ifp_internal(old_bsm, ifp->name,
 336                                                     &old_bsm->macaddr);
 337
 338                 listnode_add(bsm->ifp_list, ifname);
 339         }
 340
 341         bgp_mac_rescan_all_evpn_tables(&bsm->macaddr);
 342 }
 343
 344 void bgp_mac_del_mac_entry(struct interface *ifp)
 345 {
 346         struct bgp_self_mac lookup;
 347         struct bgp_self_mac *bsm;
 348
 349         memcpy(&lookup.macaddr, &ifp->hw_addr, ETH_ALEN);
 350         bsm = hash_lookup(bm->self_mac_hash, &lookup);
 351         if (!bsm)
 352                 return;
 353
 354         /*
 355          * Write code to allow old mac address to no-longer
 356          * win if we happen to have received it from a peer.
 357          */
 358         bgp_mac_remove_ifp_internal(bsm, ifp->name, &bsm->macaddr);
 359 }
 360
 361 /* This API checks MAC address against any of local
 362  * assigned (SVIs) MAC address.
 363  * An example: router-mac attribute in any of evpn update
 364  * requires to compare against local mac.
 365  */
 366 bool bgp_mac_exist(const struct ethaddr *mac)
 367 {
 368         struct bgp_self_mac lookup;
 369         struct bgp_self_mac *bsm;
 370         static uint8_t tmp [ETHER_ADDR_STRLEN] = {0};
 371
 372         if (memcmp(mac, &tmp, ETH_ALEN) == 0)
 373                 return false;
 374
 375         memcpy(&lookup.macaddr, mac, ETH_ALEN);
 376         bsm = hash_lookup(bm->self_mac_hash, &lookup);
 377         if (!bsm)
 378                 return false;
 379
 380         return true;
 381 }
 382
 383 /* This API checks EVPN type-2 prefix and comapares
 384  * mac against any of local assigned (SVIs) MAC
 385  * address.
 386  */
 387 bool bgp_mac_entry_exists(const struct prefix *p)
 388 {
 389         const struct prefix_evpn *pevpn = (const struct prefix_evpn *)p;
 390
 391         if (pevpn->family != AF_EVPN)
 392                 return false;
 393
 394         if (pevpn->prefix.route_type != BGP_EVPN_MAC_IP_ROUTE)
 395                 return false;
 396
 397         return bgp_mac_exist(&p->u.prefix_evpn.macip_addr.mac);
 398
 399         return true;
 400 }
 401
 402 static void bgp_mac_show_mac_entry(struct hash_bucket *bucket, void *arg)
 403 {
 404         struct vty *vty = arg;
 405         struct bgp_self_mac *bsm = bucket->data;
 406         struct listnode *node;
 407         char *name;
 408         char buf_mac[ETHER_ADDR_STRLEN];
 409
 410         vty_out(vty, "Mac Address: %s ",
 411                 prefix_mac2str(&bsm->macaddr, buf_mac, sizeof(buf_mac)));
 412
 413         for (ALL_LIST_ELEMENTS_RO(bsm->ifp_list, node, name))
 414                 vty_out(vty, "%s ", name);
 415
 416         vty_out(vty, "\n");
 417 }
 418
 419 void bgp_mac_dump_table(struct vty *vty)
 420 {
 421         hash_iterate(bm->self_mac_hash, bgp_mac_show_mac_entry, vty);
 422 }