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