nhrpd/nhrp_cache.c

   1 /* NHRP cache
   2  * Copyright (c) 2014-2015 Timo Teräs
   3  *
   4  * This file is free software: you may copy, redistribute and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 2 of the License, or
   7  * (at your option) any later version.
   8  */
   9
  10 #include "zebra.h"
  11 #include "memory.h"
  12 #include "thread.h"
  13 #include "hash.h"
  14 #include "nhrpd.h"
  15
  16 #include "netlink.h"
  17
  18 DEFINE_MTYPE_STATIC(NHRPD, NHRP_CACHE, "NHRP cache entry");
  19 DEFINE_MTYPE_STATIC(NHRPD, NHRP_CACHE_CONFIG, "NHRP cache config entry");
  20
  21 unsigned long nhrp_cache_counts[NHRP_CACHE_NUM_TYPES];
  22
  23 const char *const nhrp_cache_type_str[] = {
  24                 [NHRP_CACHE_INVALID] = "invalid",
  25                 [NHRP_CACHE_INCOMPLETE] = "incomplete",
  26                 [NHRP_CACHE_NEGATIVE] = "negative",
  27                 [NHRP_CACHE_CACHED] = "cached",
  28                 [NHRP_CACHE_DYNAMIC] = "dynamic",
  29                 [NHRP_CACHE_NHS] = "nhs",
  30                 [NHRP_CACHE_STATIC] = "static",
  31                 [NHRP_CACHE_LOCAL] = "local",
  32 };
  33
  34 static unsigned int nhrp_cache_protocol_key(const void *peer_data)
  35 {
  36         const struct nhrp_cache *p = peer_data;
  37         return sockunion_hash(&p->remote_addr);
  38 }
  39
  40 static bool nhrp_cache_protocol_cmp(const void *cache_data,
  41                                     const void *key_data)
  42 {
  43         const struct nhrp_cache *a = cache_data;
  44         const struct nhrp_cache *b = key_data;
  45
  46         return sockunion_same(&a->remote_addr, &b->remote_addr);
  47 }
  48
  49 static void *nhrp_cache_alloc(void *data)
  50 {
  51         struct nhrp_cache *p, *key = data;
  52
  53         p = XMALLOC(MTYPE_NHRP_CACHE, sizeof(struct nhrp_cache));
  54
  55         *p = (struct nhrp_cache){
  56                 .cur.type = NHRP_CACHE_INVALID,
  57                 .new.type = NHRP_CACHE_INVALID,
  58                 .remote_addr = key->remote_addr,
  59                 .ifp = key->ifp,
  60                 .notifier_list =
  61                 NOTIFIER_LIST_INITIALIZER(&p->notifier_list),
  62         };
  63         nhrp_cache_counts[p->cur.type]++;
  64
  65         return p;
  66 }
  67
  68 static void nhrp_cache_free(struct nhrp_cache *c)
  69 {
  70         struct nhrp_interface *nifp = c->ifp->info;
  71
  72         debugf(NHRP_DEBUG_COMMON, "Deleting cache entry");
  73         nhrp_cache_counts[c->cur.type]--;
  74         notifier_call(&c->notifier_list, NOTIFY_CACHE_DELETE);
  75         assert(!notifier_active(&c->notifier_list));
  76         hash_release(nifp->cache_hash, c);
  77         THREAD_OFF(c->t_timeout);
  78         THREAD_OFF(c->t_auth);
  79         XFREE(MTYPE_NHRP_CACHE, c);
  80 }
  81
  82 static unsigned int nhrp_cache_config_protocol_key(const void *peer_data)
  83 {
  84         const struct nhrp_cache_config *p = peer_data;
  85         return sockunion_hash(&p->remote_addr);
  86 }
  87
  88 static bool nhrp_cache_config_protocol_cmp(const void *cache_data,
  89                                            const void *key_data)
  90 {
  91         const struct nhrp_cache_config *a = cache_data;
  92         const struct nhrp_cache_config *b = key_data;
  93
  94         if (!sockunion_same(&a->remote_addr, &b->remote_addr))
  95                 return false;
  96         if (a->ifp != b->ifp)
  97                 return false;
  98         return true;
  99 }
 100
 101 static void *nhrp_cache_config_alloc(void *data)
 102 {
 103         struct nhrp_cache_config *p, *key = data;
 104
 105         p = XCALLOC(MTYPE_NHRP_CACHE_CONFIG, sizeof(struct nhrp_cache_config));
 106
 107         *p = (struct nhrp_cache_config){
 108                 .remote_addr = key->remote_addr,
 109                 .ifp = key->ifp,
 110         };
 111         return p;
 112 }
 113
 114 void nhrp_cache_config_free(struct nhrp_cache_config *c)
 115 {
 116         struct nhrp_interface *nifp = c->ifp->info;
 117
 118         hash_release(nifp->cache_config_hash, c);
 119         XFREE(MTYPE_NHRP_CACHE_CONFIG, c);
 120 }
 121
 122 struct nhrp_cache_config *nhrp_cache_config_get(struct interface *ifp,
 123                                                 union sockunion *remote_addr,
 124                                                 int create)
 125 {
 126         struct nhrp_interface *nifp = ifp->info;
 127         struct nhrp_cache_config key;
 128
 129         if (!nifp->cache_config_hash) {
 130                 nifp->cache_config_hash =
 131                         hash_create(nhrp_cache_config_protocol_key,
 132                                     nhrp_cache_config_protocol_cmp,
 133                                     "NHRP Config Cache");
 134                 if (!nifp->cache_config_hash)
 135                         return NULL;
 136         }
 137         key.remote_addr = *remote_addr;
 138         key.ifp = ifp;
 139
 140         return hash_get(nifp->cache_config_hash, &key,
 141                         create ? nhrp_cache_config_alloc : NULL);
 142 }
 143
 144 static void do_nhrp_cache_free(struct hash_bucket *hb,
 145                                void *arg __attribute__((__unused__)))
 146 {
 147         struct nhrp_cache *c = hb->data;
 148
 149         nhrp_cache_free(c);
 150 }
 151
 152 static void do_nhrp_cache_config_free(struct hash_bucket *hb,
 153                                       void *arg __attribute__((__unused__)))
 154 {
 155         struct nhrp_cache_config *cc = hb->data;
 156
 157         nhrp_cache_config_free(cc);
 158 }
 159
 160 void nhrp_cache_interface_del(struct interface *ifp)
 161 {
 162         struct nhrp_interface *nifp = ifp->info;
 163
 164         debugf(NHRP_DEBUG_COMMON, "Cleaning up undeleted cache entries (%lu)",
 165                nifp->cache_hash ? nifp->cache_hash->count : 0);
 166
 167         if (nifp->cache_hash) {
 168                 hash_iterate(nifp->cache_hash, do_nhrp_cache_free, NULL);
 169                 hash_free(nifp->cache_hash);
 170         }
 171
 172         if (nifp->cache_config_hash) {
 173                 hash_iterate(nifp->cache_config_hash, do_nhrp_cache_config_free,
 174                              NULL);
 175                 hash_free(nifp->cache_config_hash);
 176         }
 177 }
 178
 179 struct nhrp_cache *nhrp_cache_get(struct interface *ifp,
 180                                   union sockunion *remote_addr, int create)
 181 {
 182         struct nhrp_interface *nifp = ifp->info;
 183         struct nhrp_cache key;
 184
 185         if (!nifp->cache_hash) {
 186                 nifp->cache_hash =
 187                         hash_create(nhrp_cache_protocol_key,
 188                                     nhrp_cache_protocol_cmp, "NHRP Cache");
 189                 if (!nifp->cache_hash)
 190                         return NULL;
 191         }
 192
 193         key.remote_addr = *remote_addr;
 194         key.ifp = ifp;
 195
 196         return hash_get(nifp->cache_hash, &key,
 197                         create ? nhrp_cache_alloc : NULL);
 198 }
 199
 200 static void nhrp_cache_do_free(struct thread *t)
 201 {
 202         struct nhrp_cache *c = THREAD_ARG(t);
 203
 204         c->t_timeout = NULL;
 205         nhrp_cache_free(c);
 206 }
 207
 208 static void nhrp_cache_do_timeout(struct thread *t)
 209 {
 210         struct nhrp_cache *c = THREAD_ARG(t);
 211
 212         c->t_timeout = NULL;
 213         if (c->cur.type != NHRP_CACHE_INVALID)
 214                 nhrp_cache_update_binding(c, c->cur.type, -1, NULL, 0, NULL,
 215                                           NULL);
 216 }
 217
 218 static void nhrp_cache_update_route(struct nhrp_cache *c)
 219 {
 220         struct prefix pfx;
 221         struct nhrp_peer *p = c->cur.peer;
 222         struct nhrp_interface *nifp;
 223
 224         if (!sockunion2hostprefix(&c->remote_addr, &pfx))
 225                 return;
 226
 227         if (p && nhrp_peer_check(p, 1)) {
 228                 if (sockunion_family(&c->cur.remote_nbma_natoa) != AF_UNSPEC) {
 229                         /* remote_nbma_natoa is already set. Therefore, binding
 230                          * should be updated to this value and not vc's remote
 231                          * nbma.
 232                          */
 233                         debugf(NHRP_DEBUG_COMMON,
 234                                "cache (remote_nbma_natoa set): Update binding for %pSU dev %s from (deleted) peer.vc.nbma %pSU to %pSU",
 235                                &c->remote_addr, p->ifp->name,
 236                                &p->vc->remote.nbma, &c->cur.remote_nbma_natoa);
 237
 238                         netlink_update_binding(p->ifp, &c->remote_addr,
 239                                                &c->cur.remote_nbma_natoa);
 240                 } else {
 241                         /* update binding to peer->vc->remote->nbma */
 242                         debugf(NHRP_DEBUG_COMMON,
 243                                "cache (remote_nbma_natoa unspec): Update binding for %pSU dev %s from (deleted) to peer.vc.nbma %pSU",
 244                                &c->remote_addr, p->ifp->name,
 245                                &p->vc->remote.nbma);
 246
 247                         netlink_update_binding(p->ifp, &c->remote_addr,
 248                                                &p->vc->remote.nbma);
 249                 }
 250
 251                 nhrp_route_announce(1, c->cur.type, &pfx, c->ifp, NULL,
 252                                     c->cur.mtu);
 253                 if (c->cur.type >= NHRP_CACHE_DYNAMIC) {
 254                         nhrp_route_update_nhrp(&pfx, c->ifp);
 255                         c->nhrp_route_installed = 1;
 256                 } else if (c->nhrp_route_installed) {
 257                         nhrp_route_update_nhrp(&pfx, NULL);
 258                         c->nhrp_route_installed = 0;
 259                 }
 260                 if (!c->route_installed) {
 261                         notifier_call(&c->notifier_list, NOTIFY_CACHE_UP);
 262                         c->route_installed = 1;
 263                 }
 264         } else {
 265                 /* debug the reason for peer check fail */
 266                 if (p) {
 267                         nifp = p->ifp->info;
 268                         debugf(NHRP_DEBUG_COMMON,
 269                                "cache (peer check failed: online?%d requested?%d ipsec?%d)",
 270                                p->online, p->requested,
 271                                nifp->ipsec_profile ? 1 : 0);
 272                 } else
 273                         debugf(NHRP_DEBUG_COMMON,
 274                                "cache (peer check failed: no p)");
 275
 276                 if (c->nhrp_route_installed) {
 277                         nhrp_route_update_nhrp(&pfx, NULL);
 278                         c->nhrp_route_installed = 0;
 279                 }
 280                 if (c->route_installed) {
 281                         assert(sockunion2hostprefix(&c->remote_addr, &pfx));
 282                         notifier_call(&c->notifier_list, NOTIFY_CACHE_DOWN);
 283                         nhrp_route_announce(0, c->cur.type, &pfx, NULL, NULL,
 284                                             0);
 285                         c->route_installed = 0;
 286                 }
 287         }
 288 }
 289
 290 static void nhrp_cache_peer_notifier(struct notifier_block *n,
 291                                      unsigned long cmd)
 292 {
 293         struct nhrp_cache *c =
 294                 container_of(n, struct nhrp_cache, peer_notifier);
 295
 296         switch (cmd) {
 297         case NOTIFY_PEER_UP:
 298                 nhrp_cache_update_route(c);
 299                 break;
 300         case NOTIFY_PEER_DOWN:
 301         case NOTIFY_PEER_IFCONFIG_CHANGED:
 302                 notifier_call(&c->notifier_list, NOTIFY_CACHE_DOWN);
 303                 nhrp_cache_update_binding(c, c->cur.type, -1, NULL, 0, NULL,
 304                                           NULL);
 305                 break;
 306         case NOTIFY_PEER_NBMA_CHANGING:
 307                 if (c->cur.type == NHRP_CACHE_DYNAMIC)
 308                         c->cur.peer->vc->abort_migration = 1;
 309                 break;
 310         }
 311 }
 312
 313 static void nhrp_cache_reset_new(struct nhrp_cache *c)
 314 {
 315         THREAD_OFF(c->t_auth);
 316         if (notifier_list_anywhere(&c->newpeer_notifier))
 317                 nhrp_peer_notify_del(c->new.peer, &c->newpeer_notifier);
 318         nhrp_peer_unref(c->new.peer);
 319         memset(&c->new, 0, sizeof(c->new));
 320         c->new.type = NHRP_CACHE_INVALID;
 321 }
 322
 323 static void nhrp_cache_update_timers(struct nhrp_cache *c)
 324 {
 325         THREAD_OFF(c->t_timeout);
 326
 327         switch (c->cur.type) {
 328         case NHRP_CACHE_INVALID:
 329                 if (!c->t_auth)
 330                         thread_add_timer_msec(master, nhrp_cache_do_free, c, 10,
 331                                               &c->t_timeout);
 332                 break;
 333         default:
 334                 if (c->cur.expires)
 335                         thread_add_timer(master, nhrp_cache_do_timeout, c,
 336                                          c->cur.expires - monotime(NULL),
 337                                          &c->t_timeout);
 338                 break;
 339         }
 340 }
 341
 342 static void nhrp_cache_authorize_binding(struct nhrp_reqid *r, void *arg)
 343 {
 344         struct nhrp_cache *c = container_of(r, struct nhrp_cache, eventid);
 345         char buf[3][SU_ADDRSTRLEN];
 346
 347         debugf(NHRP_DEBUG_COMMON, "cache: %s %pSU: %s", c->ifp->name,
 348                &c->remote_addr, (const char *)arg);
 349
 350         nhrp_reqid_free(&nhrp_event_reqid, r);
 351
 352         if (arg && strcmp(arg, "accept") == 0) {
 353                 if (c->cur.peer) {
 354                         netlink_update_binding(c->cur.peer->ifp,
 355                                                &c->remote_addr, NULL);
 356                         nhrp_peer_notify_del(c->cur.peer, &c->peer_notifier);
 357                         nhrp_peer_unref(c->cur.peer);
 358                 }
 359                 nhrp_cache_counts[c->cur.type]--;
 360                 nhrp_cache_counts[c->new.type]++;
 361                 c->cur = c->new;
 362                 c->cur.peer = nhrp_peer_ref(c->cur.peer);
 363                 nhrp_cache_reset_new(c);
 364                 if (c->cur.peer)
 365                         nhrp_peer_notify_add(c->cur.peer, &c->peer_notifier,
 366                                              nhrp_cache_peer_notifier);
 367
 368                 if (sockunion_family(&c->cur.remote_nbma_natoa) != AF_UNSPEC) {
 369                         debugf(NHRP_DEBUG_COMMON,
 370                                "cache: update binding for %pSU dev %s from (deleted) peer.vc.nbma %s to %pSU",
 371                                &c->remote_addr, c->ifp->name,
 372                                (c->cur.peer ? sockunion2str(
 373                                         &c->cur.peer->vc->remote.nbma, buf[1],
 374                                         sizeof(buf[1]))
 375                                             : "(no peer)"),
 376                                &c->cur.remote_nbma_natoa);
 377
 378                         if (c->cur.peer)
 379                                 netlink_update_binding(
 380                                         c->cur.peer->ifp, &c->remote_addr,
 381                                         &c->cur.remote_nbma_natoa);
 382                 }
 383
 384                 nhrp_cache_update_route(c);
 385                 notifier_call(&c->notifier_list, NOTIFY_CACHE_BINDING_CHANGE);
 386         } else {
 387                 nhrp_cache_reset_new(c);
 388         }
 389
 390         nhrp_cache_update_timers(c);
 391 }
 392
 393 static void nhrp_cache_do_auth_timeout(struct thread *t)
 394 {
 395         struct nhrp_cache *c = THREAD_ARG(t);
 396         c->t_auth = NULL;
 397         nhrp_cache_authorize_binding(&c->eventid, (void *)"timeout");
 398 }
 399
 400 static void nhrp_cache_newpeer_notifier(struct notifier_block *n,
 401                                         unsigned long cmd)
 402 {
 403         struct nhrp_cache *c =
 404                 container_of(n, struct nhrp_cache, newpeer_notifier);
 405
 406         switch (cmd) {
 407         case NOTIFY_PEER_UP:
 408                 if (nhrp_peer_check(c->new.peer, 1)) {
 409                         evmgr_notify("authorize-binding", c,
 410                                      nhrp_cache_authorize_binding);
 411                         thread_add_timer(master, nhrp_cache_do_auth_timeout, c,
 412                                          10, &c->t_auth);
 413                 }
 414                 break;
 415         case NOTIFY_PEER_DOWN:
 416         case NOTIFY_PEER_IFCONFIG_CHANGED:
 417                 nhrp_cache_reset_new(c);
 418                 break;
 419         }
 420 }
 421
 422 int nhrp_cache_update_binding(struct nhrp_cache *c, enum nhrp_cache_type type,
 423                               int holding_time, struct nhrp_peer *p,
 424                               uint32_t mtu, union sockunion *nbma_oa,
 425                               union sockunion *nbma_claimed)
 426 {
 427         char buf[2][SU_ADDRSTRLEN];
 428
 429         if (c->cur.type > type || c->new.type > type) {
 430                 nhrp_peer_unref(p);
 431                 return 0;
 432         }
 433
 434         /* Sanitize MTU */
 435         switch (sockunion_family(&c->remote_addr)) {
 436         case AF_INET:
 437                 if (mtu < 576 || mtu >= 1500)
 438                         mtu = 0;
 439                 /* Opennhrp announces nbma mtu, but we use protocol mtu.
 440                  * This heuristic tries to fix up it. */
 441                 if (mtu > 1420)
 442                         mtu = (mtu & -16) - 80;
 443                 break;
 444         default:
 445                 mtu = 0;
 446                 break;
 447         }
 448
 449         sockunion2str(&c->cur.remote_nbma_natoa, buf[0], sizeof(buf[0]));
 450         if (nbma_oa)
 451                 sockunion2str(nbma_oa, buf[1], sizeof(buf[1]));
 452
 453         nhrp_cache_reset_new(c);
 454         if (c->cur.type == type && c->cur.peer == p && c->cur.mtu == mtu) {
 455                 debugf(NHRP_DEBUG_COMMON,
 456                        "cache: same type %u, updating expiry and changing nbma addr from %s to %s",
 457                        type, buf[0], nbma_oa ? buf[1] : "(NULL)");
 458                 if (holding_time > 0)
 459                         c->cur.expires = monotime(NULL) + holding_time;
 460
 461                 if (nbma_oa)
 462                         c->cur.remote_nbma_natoa = *nbma_oa;
 463                 else
 464                         memset(&c->cur.remote_nbma_natoa, 0,
 465                                sizeof(c->cur.remote_nbma_natoa));
 466
 467                 if (nbma_claimed)
 468                         c->cur.remote_nbma_claimed = *nbma_claimed;
 469                 else
 470                         memset(&c->cur.remote_nbma_claimed, 0,
 471                                sizeof(c->cur.remote_nbma_claimed));
 472
 473                 nhrp_peer_unref(p);
 474         } else {
 475                 debugf(NHRP_DEBUG_COMMON,
 476                        "cache: new type %u/%u, or peer %s, or mtu %u/%u, nbma %s --> %s (map %d)",
 477                        c->cur.type, type, (c->cur.peer == p) ? "same" : "diff",
 478                        c->cur.mtu, mtu, buf[0], nbma_oa ? buf[1] : "(NULL)",
 479                        c->map);
 480                 c->new.type = type;
 481                 c->new.peer = p;
 482                 c->new.mtu = mtu;
 483                 c->new.holding_time = holding_time;
 484                 if (nbma_oa)
 485                         c->new.remote_nbma_natoa = *nbma_oa;
 486
 487                 if (nbma_claimed)
 488                         c->new.remote_nbma_claimed = *nbma_claimed;
 489
 490                 if (holding_time > 0)
 491                         c->new.expires = monotime(NULL) + holding_time;
 492                 else if (holding_time < 0)
 493                         nhrp_cache_reset_new(c);
 494
 495                 if (c->new.type == NHRP_CACHE_INVALID
 496                     || c->new.type >= NHRP_CACHE_STATIC || c->map) {
 497                         nhrp_cache_authorize_binding(&c->eventid,
 498                                                      (void *)"accept");
 499                 } else {
 500                         nhrp_peer_notify_add(c->new.peer, &c->newpeer_notifier,
 501                                              nhrp_cache_newpeer_notifier);
 502                         nhrp_cache_newpeer_notifier(&c->newpeer_notifier,
 503                                                     NOTIFY_PEER_UP);
 504                         thread_add_timer(master, nhrp_cache_do_auth_timeout, c,
 505                                          60, &c->t_auth);
 506                 }
 507         }
 508         nhrp_cache_update_timers(c);
 509
 510         return 1;
 511 }
 512
 513 void nhrp_cache_set_used(struct nhrp_cache *c, int used)
 514 {
 515         c->used = used;
 516         if (c->used)
 517                 notifier_call(&c->notifier_list, NOTIFY_CACHE_USED);
 518 }
 519
 520 struct nhrp_cache_iterator_ctx {
 521         void (*cb)(struct nhrp_cache *, void *);
 522         void *ctx;
 523 };
 524
 525 struct nhrp_cache_config_iterator_ctx {
 526         void (*cb)(struct nhrp_cache_config *, void *);
 527         void *ctx;
 528 };
 529
 530 static void nhrp_cache_iterator(struct hash_bucket *b, void *ctx)
 531 {
 532         struct nhrp_cache_iterator_ctx *ic = ctx;
 533         ic->cb(b->data, ic->ctx);
 534 }
 535
 536 static void nhrp_cache_config_iterator(struct hash_bucket *b, void *ctx)
 537 {
 538         struct nhrp_cache_config_iterator_ctx *ic = ctx;
 539         ic->cb(b->data, ic->ctx);
 540 }
 541
 542 void nhrp_cache_foreach(struct interface *ifp,
 543                         void (*cb)(struct nhrp_cache *, void *), void *ctx)
 544 {
 545         struct nhrp_interface *nifp = ifp->info;
 546         struct nhrp_cache_iterator_ctx ic = {
 547                 .cb = cb, .ctx = ctx,
 548         };
 549
 550         if (nifp->cache_hash)
 551                 hash_iterate(nifp->cache_hash, nhrp_cache_iterator, &ic);
 552 }
 553
 554 void nhrp_cache_config_foreach(struct interface *ifp,
 555                                void (*cb)(struct nhrp_cache_config *, void *), void *ctx)
 556 {
 557         struct nhrp_interface *nifp = ifp->info;
 558         struct nhrp_cache_config_iterator_ctx ic = {
 559                 .cb = cb, .ctx = ctx,
 560         };
 561
 562         if (nifp->cache_config_hash)
 563                 hash_iterate(nifp->cache_config_hash, nhrp_cache_config_iterator, &ic);
 564 }
 565
 566 void nhrp_cache_notify_add(struct nhrp_cache *c, struct notifier_block *n,
 567                            notifier_fn_t fn)
 568 {
 569         notifier_add(n, &c->notifier_list, fn);
 570 }
 571
 572 void nhrp_cache_notify_del(struct nhrp_cache *c, struct notifier_block *n)
 573 {
 574         notifier_del(n, &c->notifier_list);
 575 }