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, NULL,
 204                                                 pfx_buf, 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, bgp_attr_get_evpn_overlay(pi->attr),
 213                                sizeof(evpn));
 214                         bgp_update(peer, p, pi->addpath_rx_id, pi->attr,
 215                                    AFI_L2VPN, SAFI_EVPN, ZEBRA_ROUTE_BGP,
 216                                    BGP_ROUTE_NORMAL, &prd, label_pnt,
 217                                    num_labels, 1, evpn);
 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_established(peer))
 237                         continue;
 238
 239                 if (bgp_debug_update(peer, NULL, NULL, 1))
 240                         zlog_debug(
 241                                 "Processing EVPN MAC interface change on peer %s %s",
 242                                 peer->host,
 243                                 CHECK_FLAG(peer->af_flags[afi][safi],
 244                                            PEER_FLAG_SOFT_RECONFIG)
 245                                         ? "(inbound, soft-reconfig)"
 246                                         : "");
 247
 248                 if (!bgp_soft_reconfig_in(peer, afi, safi)) {
 249                         struct bgp_table *table = bgp->rib[afi][safi];
 250
 251                         bgp_process_mac_rescan_table(bgp, peer, table, macaddr);
 252                 }
 253         }
 254 }
 255
 256 static void bgp_mac_rescan_all_evpn_tables(struct ethaddr *macaddr)
 257 {
 258         struct listnode *node;
 259         struct bgp *bgp;
 260
 261         for (ALL_LIST_ELEMENTS_RO(bm->bgp, node, bgp)) {
 262                 struct bgp_table *table = bgp->rib[AFI_L2VPN][SAFI_EVPN];
 263
 264                 if (table)
 265                         bgp_mac_rescan_evpn_table(bgp, macaddr);
 266         }
 267 }
 268
 269 static void bgp_mac_remove_ifp_internal(struct bgp_self_mac *bsm, char *ifname,
 270                                         struct ethaddr *macaddr)
 271 {
 272         struct listnode *node = NULL;
 273         char *name;
 274
 275         for (ALL_LIST_ELEMENTS_RO(bsm->ifp_list, node, name)) {
 276                 if (strcmp(name, ifname) == 0)
 277                         break;
 278         }
 279
 280         if (node) {
 281                 list_delete_node(bsm->ifp_list, node);
 282                 XFREE(MTYPE_BSM_STRING, name);
 283         }
 284
 285         if (bsm->ifp_list->count == 0) {
 286                 struct ethaddr mac = *macaddr;
 287
 288                 hash_release(bm->self_mac_hash, bsm);
 289                 list_delete(&bsm->ifp_list);
 290                 XFREE(MTYPE_BSM, bsm);
 291
 292                 bgp_mac_rescan_all_evpn_tables(&mac);
 293         }
 294 }
 295
 296 void bgp_mac_add_mac_entry(struct interface *ifp)
 297 {
 298         struct bgp_self_mac lookup;
 299         struct bgp_self_mac *bsm;
 300         struct bgp_self_mac *old_bsm;
 301         char *ifname;
 302
 303         memcpy(&lookup.macaddr, &ifp->hw_addr, ETH_ALEN);
 304         bsm = hash_get(bm->self_mac_hash, &lookup, bgp_mac_hash_alloc);
 305
 306         /*
 307          * Does this happen to be a move
 308          */
 309         old_bsm = bgp_mac_find_interface_name(ifp->name);
 310         ifname = XSTRDUP(MTYPE_BSM_STRING, ifp->name);
 311
 312         if (bsm->ifp_list->count == 0) {
 313
 314                 listnode_add(bsm->ifp_list, ifname);
 315                 if (old_bsm)
 316                         bgp_mac_remove_ifp_internal(old_bsm, ifname,
 317                                                     &old_bsm->macaddr);
 318         } else {
 319                 /*
 320                  * If old mac address is the same as the new,
 321                  * then there is nothing to do here
 322                  */
 323                 if (old_bsm == bsm) {
 324                         XFREE(MTYPE_BSM_STRING, ifname);
 325                         return;
 326                 }
 327
 328                 if (old_bsm)
 329                         bgp_mac_remove_ifp_internal(old_bsm, ifp->name,
 330                                                     &old_bsm->macaddr);
 331
 332                 listnode_add(bsm->ifp_list, ifname);
 333         }
 334
 335         bgp_mac_rescan_all_evpn_tables(&bsm->macaddr);
 336 }
 337
 338 void bgp_mac_del_mac_entry(struct interface *ifp)
 339 {
 340         struct bgp_self_mac lookup;
 341         struct bgp_self_mac *bsm;
 342
 343         memcpy(&lookup.macaddr, &ifp->hw_addr, ETH_ALEN);
 344         bsm = hash_lookup(bm->self_mac_hash, &lookup);
 345         if (!bsm)
 346                 return;
 347
 348         /*
 349          * Write code to allow old mac address to no-longer
 350          * win if we happen to have received it from a peer.
 351          */
 352         bgp_mac_remove_ifp_internal(bsm, ifp->name, &bsm->macaddr);
 353 }
 354
 355 /* This API checks MAC address against any of local
 356  * assigned (SVIs) MAC address.
 357  * An example: router-mac attribute in any of evpn update
 358  * requires to compare against local mac.
 359  */
 360 bool bgp_mac_exist(const struct ethaddr *mac)
 361 {
 362         struct bgp_self_mac lookup;
 363         struct bgp_self_mac *bsm;
 364         static uint8_t tmp [ETHER_ADDR_STRLEN] = {0};
 365
 366         if (memcmp(mac, &tmp, ETH_ALEN) == 0)
 367                 return false;
 368
 369         memcpy(&lookup.macaddr, mac, ETH_ALEN);
 370         bsm = hash_lookup(bm->self_mac_hash, &lookup);
 371         if (!bsm)
 372                 return false;
 373
 374         return true;
 375 }
 376
 377 /* This API checks EVPN type-2 prefix and comapares
 378  * mac against any of local assigned (SVIs) MAC
 379  * address.
 380  */
 381 bool bgp_mac_entry_exists(const struct prefix *p)
 382 {
 383         const struct prefix_evpn *pevpn = (const struct prefix_evpn *)p;
 384
 385         if (pevpn->family != AF_EVPN)
 386                 return false;
 387
 388         if (pevpn->prefix.route_type != BGP_EVPN_MAC_IP_ROUTE)
 389                 return false;
 390
 391         return bgp_mac_exist(&p->u.prefix_evpn.macip_addr.mac);
 392
 393         return true;
 394 }
 395
 396 static void bgp_mac_show_mac_entry(struct hash_bucket *bucket, void *arg)
 397 {
 398         struct vty *vty = arg;
 399         struct bgp_self_mac *bsm = bucket->data;
 400         struct listnode *node;
 401         char *name;
 402         char buf_mac[ETHER_ADDR_STRLEN];
 403
 404         vty_out(vty, "Mac Address: %s ",
 405                 prefix_mac2str(&bsm->macaddr, buf_mac, sizeof(buf_mac)));
 406
 407         for (ALL_LIST_ELEMENTS_RO(bsm->ifp_list, node, name))
 408                 vty_out(vty, "%s ", name);
 409
 410         vty_out(vty, "\n");
 411 }
 412
 413 void bgp_mac_dump_table(struct vty *vty)
 414 {
 415         hash_iterate(bm->self_mac_hash, bgp_mac_show_mac_entry, vty);
 416 }