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 int 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         return 0;
 207 }
 208
 209 static int nhrp_cache_do_timeout(struct thread *t)
 210 {
 211         struct nhrp_cache *c = THREAD_ARG(t);
 212
 213         c->t_timeout = NULL;
 214         if (c->cur.type != NHRP_CACHE_INVALID)
 215                 nhrp_cache_update_binding(c, c->cur.type, -1, NULL, 0, NULL,
 216                                           NULL);
 217         return 0;
 218 }
 219
 220 static void nhrp_cache_update_route(struct nhrp_cache *c)
 221 {
 222         struct prefix pfx;
 223         struct nhrp_peer *p = c->cur.peer;
 224         struct nhrp_interface *nifp;
 225
 226         if (!sockunion2hostprefix(&c->remote_addr, &pfx))
 227                 return;
 228
 229         if (p && nhrp_peer_check(p, 1)) {
 230                 if (sockunion_family(&c->cur.remote_nbma_natoa) != AF_UNSPEC) {
 231                         /* remote_nbma_natoa is already set. Therefore, binding
 232                          * should be updated to this value and not vc's remote
 233                          * nbma.
 234                          */
 235                         debugf(NHRP_DEBUG_COMMON,
 236                                "cache (remote_nbma_natoa set): Update binding for %pSU dev %s from (deleted) peer.vc.nbma %pSU to %pSU",
 237                                &c->remote_addr, p->ifp->name,
 238                                &p->vc->remote.nbma, &c->cur.remote_nbma_natoa);
 239
 240                         netlink_update_binding(p->ifp, &c->remote_addr,
 241                                                &c->cur.remote_nbma_natoa);
 242                 } else {
 243                         /* update binding to peer->vc->remote->nbma */
 244                         debugf(NHRP_DEBUG_COMMON,
 245                                "cache (remote_nbma_natoa unspec): Update binding for %pSU dev %s from (deleted) to peer.vc.nbma %pSU",
 246                                &c->remote_addr, p->ifp->name,
 247                                &p->vc->remote.nbma);
 248
 249                         netlink_update_binding(p->ifp, &c->remote_addr,
 250                                                &p->vc->remote.nbma);
 251                 }
 252
 253                 nhrp_route_announce(1, c->cur.type, &pfx, c->ifp, NULL,
 254                                     c->cur.mtu);
 255                 if (c->cur.type >= NHRP_CACHE_DYNAMIC) {
 256                         nhrp_route_update_nhrp(&pfx, c->ifp);
 257                         c->nhrp_route_installed = 1;
 258                 } else if (c->nhrp_route_installed) {
 259                         nhrp_route_update_nhrp(&pfx, NULL);
 260                         c->nhrp_route_installed = 0;
 261                 }
 262                 if (!c->route_installed) {
 263                         notifier_call(&c->notifier_list, NOTIFY_CACHE_UP);
 264                         c->route_installed = 1;
 265                 }
 266         } else {
 267                 /* debug the reason for peer check fail */
 268                 if (p) {
 269                         nifp = p->ifp->info;
 270                         debugf(NHRP_DEBUG_COMMON,
 271                                "cache (peer check failed: online?%d requested?%d ipsec?%d)",
 272                                p->online, p->requested,
 273                                nifp->ipsec_profile ? 1 : 0);
 274                 } else
 275                         debugf(NHRP_DEBUG_COMMON,
 276                                "cache (peer check failed: no p)");
 277
 278                 if (c->nhrp_route_installed) {
 279                         nhrp_route_update_nhrp(&pfx, NULL);
 280                         c->nhrp_route_installed = 0;
 281                 }
 282                 if (c->route_installed) {
 283                         assert(sockunion2hostprefix(&c->remote_addr, &pfx));
 284                         notifier_call(&c->notifier_list, NOTIFY_CACHE_DOWN);
 285                         nhrp_route_announce(0, c->cur.type, &pfx, NULL, NULL,
 286                                             0);
 287                         c->route_installed = 0;
 288                 }
 289         }
 290 }
 291
 292 static void nhrp_cache_peer_notifier(struct notifier_block *n,
 293                                      unsigned long cmd)
 294 {
 295         struct nhrp_cache *c =
 296                 container_of(n, struct nhrp_cache, peer_notifier);
 297
 298         switch (cmd) {
 299         case NOTIFY_PEER_UP:
 300                 nhrp_cache_update_route(c);
 301                 break;
 302         case NOTIFY_PEER_DOWN:
 303         case NOTIFY_PEER_IFCONFIG_CHANGED:
 304                 notifier_call(&c->notifier_list, NOTIFY_CACHE_DOWN);
 305                 nhrp_cache_update_binding(c, c->cur.type, -1, NULL, 0, NULL,
 306                                           NULL);
 307                 break;
 308         case NOTIFY_PEER_NBMA_CHANGING:
 309                 if (c->cur.type == NHRP_CACHE_DYNAMIC)
 310                         c->cur.peer->vc->abort_migration = 1;
 311                 break;
 312         }
 313 }
 314
 315 static void nhrp_cache_reset_new(struct nhrp_cache *c)
 316 {
 317         THREAD_OFF(c->t_auth);
 318         if (list_hashed(&c->newpeer_notifier.notifier_entry))
 319                 nhrp_peer_notify_del(c->new.peer, &c->newpeer_notifier);
 320         nhrp_peer_unref(c->new.peer);
 321         memset(&c->new, 0, sizeof(c->new));
 322         c->new.type = NHRP_CACHE_INVALID;
 323 }
 324
 325 static void nhrp_cache_update_timers(struct nhrp_cache *c)
 326 {
 327         THREAD_OFF(c->t_timeout);
 328
 329         switch (c->cur.type) {
 330         case NHRP_CACHE_INVALID:
 331                 if (!c->t_auth)
 332                         thread_add_timer_msec(master, nhrp_cache_do_free, c, 10,
 333                                               &c->t_timeout);
 334                 break;
 335         default:
 336                 if (c->cur.expires)
 337                         thread_add_timer(master, nhrp_cache_do_timeout, c,
 338                                          c->cur.expires - monotime(NULL),
 339                                          &c->t_timeout);
 340                 break;
 341         }
 342 }
 343
 344 static void nhrp_cache_authorize_binding(struct nhrp_reqid *r, void *arg)
 345 {
 346         struct nhrp_cache *c = container_of(r, struct nhrp_cache, eventid);
 347         char buf[3][SU_ADDRSTRLEN];
 348
 349         debugf(NHRP_DEBUG_COMMON, "cache: %s %pSU: %s", c->ifp->name,
 350                &c->remote_addr, (const char *)arg);
 351
 352         nhrp_reqid_free(&nhrp_event_reqid, r);
 353
 354         if (arg && strcmp(arg, "accept") == 0) {
 355                 if (c->cur.peer) {
 356                         netlink_update_binding(c->cur.peer->ifp,
 357                                                &c->remote_addr, NULL);
 358                         nhrp_peer_notify_del(c->cur.peer, &c->peer_notifier);
 359                         nhrp_peer_unref(c->cur.peer);
 360                 }
 361                 nhrp_cache_counts[c->cur.type]--;
 362                 nhrp_cache_counts[c->new.type]++;
 363                 c->cur = c->new;
 364                 c->cur.peer = nhrp_peer_ref(c->cur.peer);
 365                 nhrp_cache_reset_new(c);
 366                 if (c->cur.peer)
 367                         nhrp_peer_notify_add(c->cur.peer, &c->peer_notifier,
 368                                              nhrp_cache_peer_notifier);
 369
 370                 if (sockunion_family(&c->cur.remote_nbma_natoa) != AF_UNSPEC) {
 371                         debugf(NHRP_DEBUG_COMMON,
 372                                "cache: update binding for %pSU dev %s from (deleted) peer.vc.nbma %s to %pSU",
 373                                &c->remote_addr, c->ifp->name,
 374                                (c->cur.peer ? sockunion2str(
 375                                         &c->cur.peer->vc->remote.nbma, buf[1],
 376                                         sizeof(buf[1]))
 377                                             : "(no peer)"),
 378                                &c->cur.remote_nbma_natoa);
 379
 380                         if (c->cur.peer)
 381                                 netlink_update_binding(
 382                                         c->cur.peer->ifp, &c->remote_addr,
 383                                         &c->cur.remote_nbma_natoa);
 384                 }
 385
 386                 nhrp_cache_update_route(c);
 387                 notifier_call(&c->notifier_list, NOTIFY_CACHE_BINDING_CHANGE);
 388         } else {
 389                 nhrp_cache_reset_new(c);
 390         }
 391
 392         nhrp_cache_update_timers(c);
 393 }
 394
 395 static int nhrp_cache_do_auth_timeout(struct thread *t)
 396 {
 397         struct nhrp_cache *c = THREAD_ARG(t);
 398         c->t_auth = NULL;
 399         nhrp_cache_authorize_binding(&c->eventid, (void *)"timeout");
 400         return 0;
 401 }
 402
 403 static void nhrp_cache_newpeer_notifier(struct notifier_block *n,
 404                                         unsigned long cmd)
 405 {
 406         struct nhrp_cache *c =
 407                 container_of(n, struct nhrp_cache, newpeer_notifier);
 408
 409         switch (cmd) {
 410         case NOTIFY_PEER_UP:
 411                 if (nhrp_peer_check(c->new.peer, 1)) {
 412                         evmgr_notify("authorize-binding", c,
 413                                      nhrp_cache_authorize_binding);
 414                         thread_add_timer(master, nhrp_cache_do_auth_timeout, c,
 415                                          10, &c->t_auth);
 416                 }
 417                 break;
 418         case NOTIFY_PEER_DOWN:
 419         case NOTIFY_PEER_IFCONFIG_CHANGED:
 420                 nhrp_cache_reset_new(c);
 421                 break;
 422         }
 423 }
 424
 425 int nhrp_cache_update_binding(struct nhrp_cache *c, enum nhrp_cache_type type,
 426                               int holding_time, struct nhrp_peer *p,
 427                               uint32_t mtu, union sockunion *nbma_oa,
 428                               union sockunion *nbma_claimed)
 429 {
 430         char buf[2][SU_ADDRSTRLEN];
 431
 432         if (c->cur.type > type || c->new.type > type) {
 433                 nhrp_peer_unref(p);
 434                 return 0;
 435         }
 436
 437         /* Sanitize MTU */
 438         switch (sockunion_family(&c->remote_addr)) {
 439         case AF_INET:
 440                 if (mtu < 576 || mtu >= 1500)
 441                         mtu = 0;
 442                 /* Opennhrp announces nbma mtu, but we use protocol mtu.
 443                  * This heuristic tries to fix up it. */
 444                 if (mtu > 1420)
 445                         mtu = (mtu & -16) - 80;
 446                 break;
 447         default:
 448                 mtu = 0;
 449                 break;
 450         }
 451
 452         sockunion2str(&c->cur.remote_nbma_natoa, buf[0], sizeof(buf[0]));
 453         if (nbma_oa)
 454                 sockunion2str(nbma_oa, buf[1], sizeof(buf[1]));
 455
 456         nhrp_cache_reset_new(c);
 457         if (c->cur.type == type && c->cur.peer == p && c->cur.mtu == mtu) {
 458                 debugf(NHRP_DEBUG_COMMON,
 459                        "cache: same type %u, updating expiry and changing nbma addr from %s to %s",
 460                        type, buf[0], nbma_oa ? buf[1] : "(NULL)");
 461                 if (holding_time > 0)
 462                         c->cur.expires = monotime(NULL) + holding_time;
 463
 464                 if (nbma_oa)
 465                         c->cur.remote_nbma_natoa = *nbma_oa;
 466                 else
 467                         memset(&c->cur.remote_nbma_natoa, 0,
 468                                sizeof(c->cur.remote_nbma_natoa));
 469
 470                 if (nbma_claimed)
 471                         c->cur.remote_nbma_claimed = *nbma_claimed;
 472                 else
 473                         memset(&c->cur.remote_nbma_claimed, 0,
 474                                sizeof(c->cur.remote_nbma_claimed));
 475
 476                 nhrp_peer_unref(p);
 477         } else {
 478                 debugf(NHRP_DEBUG_COMMON,
 479                        "cache: new type %u/%u, or peer %s, or mtu %u/%u, nbma %s --> %s (map %d)",
 480                        c->cur.type, type, (c->cur.peer == p) ? "same" : "diff",
 481                        c->cur.mtu, mtu, buf[0], nbma_oa ? buf[1] : "(NULL)",
 482                        c->map);
 483                 c->new.type = type;
 484                 c->new.peer = p;
 485                 c->new.mtu = mtu;
 486                 c->new.holding_time = holding_time;
 487                 if (nbma_oa)
 488                         c->new.remote_nbma_natoa = *nbma_oa;
 489
 490                 if (nbma_claimed)
 491                         c->new.remote_nbma_claimed = *nbma_claimed;
 492
 493                 if (holding_time > 0)
 494                         c->new.expires = monotime(NULL) + holding_time;
 495                 else if (holding_time < 0)
 496                         nhrp_cache_reset_new(c);
 497
 498                 if (c->new.type == NHRP_CACHE_INVALID
 499                     || c->new.type >= NHRP_CACHE_STATIC || c->map) {
 500                         nhrp_cache_authorize_binding(&c->eventid,
 501                                                      (void *)"accept");
 502                 } else {
 503                         nhrp_peer_notify_add(c->new.peer, &c->newpeer_notifier,
 504                                              nhrp_cache_newpeer_notifier);
 505                         nhrp_cache_newpeer_notifier(&c->newpeer_notifier,
 506                                                     NOTIFY_PEER_UP);
 507                         thread_add_timer(master, nhrp_cache_do_auth_timeout, c,
 508                                          60, &c->t_auth);
 509                 }
 510         }
 511         nhrp_cache_update_timers(c);
 512
 513         return 1;
 514 }
 515
 516 void nhrp_cache_set_used(struct nhrp_cache *c, int used)
 517 {
 518         c->used = used;
 519         if (c->used)
 520                 notifier_call(&c->notifier_list, NOTIFY_CACHE_USED);
 521 }
 522
 523 struct nhrp_cache_iterator_ctx {
 524         void (*cb)(struct nhrp_cache *, void *);
 525         void *ctx;
 526 };
 527
 528 struct nhrp_cache_config_iterator_ctx {
 529         void (*cb)(struct nhrp_cache_config *, void *);
 530         void *ctx;
 531 };
 532
 533 static void nhrp_cache_iterator(struct hash_bucket *b, void *ctx)
 534 {
 535         struct nhrp_cache_iterator_ctx *ic = ctx;
 536         ic->cb(b->data, ic->ctx);
 537 }
 538
 539 static void nhrp_cache_config_iterator(struct hash_bucket *b, void *ctx)
 540 {
 541         struct nhrp_cache_config_iterator_ctx *ic = ctx;
 542         ic->cb(b->data, ic->ctx);
 543 }
 544
 545 void nhrp_cache_foreach(struct interface *ifp,
 546                         void (*cb)(struct nhrp_cache *, void *), void *ctx)
 547 {
 548         struct nhrp_interface *nifp = ifp->info;
 549         struct nhrp_cache_iterator_ctx ic = {
 550                 .cb = cb, .ctx = ctx,
 551         };
 552
 553         if (nifp->cache_hash)
 554                 hash_iterate(nifp->cache_hash, nhrp_cache_iterator, &ic);
 555 }
 556
 557 void nhrp_cache_config_foreach(struct interface *ifp,
 558                                void (*cb)(struct nhrp_cache_config *, void *), void *ctx)
 559 {
 560         struct nhrp_interface *nifp = ifp->info;
 561         struct nhrp_cache_config_iterator_ctx ic = {
 562                 .cb = cb, .ctx = ctx,
 563         };
 564
 565         if (nifp->cache_config_hash)
 566                 hash_iterate(nifp->cache_config_hash, nhrp_cache_config_iterator, &ic);
 567 }
 568
 569 void nhrp_cache_notify_add(struct nhrp_cache *c, struct notifier_block *n,
 570                            notifier_fn_t fn)
 571 {
 572         notifier_add(n, &c->notifier_list, fn);
 573 }
 574
 575 void nhrp_cache_notify_del(struct nhrp_cache *c, struct notifier_block *n)
 576 {
 577         notifier_del(n);
 578 }