1 /* 2 * net/tipc/name_table.c: TIPC name table code 3 * 4 * Copyright (c) 2000-2006, 2014-2015, Ericsson AB 5 * Copyright (c) 2004-2008, 2010-2014, Wind River Systems 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the names of the copyright holders nor the names of its 17 * contributors may be used to endorse or promote products derived from 18 * this software without specific prior written permission. 19 * 20 * Alternatively, this software may be distributed under the terms of the 21 * GNU General Public License ("GPL") version 2 as published by the Free 22 * Software Foundation. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 34 * POSSIBILITY OF SUCH DAMAGE. 35 */ 36 37 #include <net/sock.h> 38 #include "core.h" 39 #include "netlink.h" 40 #include "name_table.h" 41 #include "name_distr.h" 42 #include "subscr.h" 43 #include "bcast.h" 44 #include "addr.h" 45 #include "node.h" 46 #include <net/genetlink.h> 47 48 #define TIPC_NAMETBL_SIZE 1024 /* must be a power of 2 */ 49 50 static const struct nla_policy 51 tipc_nl_name_table_policy[TIPC_NLA_NAME_TABLE_MAX + 1] = { 52 [TIPC_NLA_NAME_TABLE_UNSPEC] = { .type = NLA_UNSPEC }, 53 [TIPC_NLA_NAME_TABLE_PUBL] = { .type = NLA_NESTED } 54 }; 55 56 /** 57 * struct name_info - name sequence publication info 58 * @node_list: circular list of publications made by own node 59 * @cluster_list: circular list of publications made by own cluster 60 * @zone_list: circular list of publications made by own zone 61 * @node_list_size: number of entries in "node_list" 62 * @cluster_list_size: number of entries in "cluster_list" 63 * @zone_list_size: number of entries in "zone_list" 64 * 65 * Note: The zone list always contains at least one entry, since all 66 * publications of the associated name sequence belong to it. 67 * (The cluster and node lists may be empty.) 68 */ 69 struct name_info { 70 struct list_head node_list; 71 struct list_head cluster_list; 72 struct list_head zone_list; 73 u32 node_list_size; 74 u32 cluster_list_size; 75 u32 zone_list_size; 76 }; 77 78 /** 79 * struct sub_seq - container for all published instances of a name sequence 80 * @lower: name sequence lower bound 81 * @upper: name sequence upper bound 82 * @info: pointer to name sequence publication info 83 */ 84 struct sub_seq { 85 u32 lower; 86 u32 upper; 87 struct name_info *info; 88 }; 89 90 /** 91 * struct name_seq - container for all published instances of a name type 92 * @type: 32 bit 'type' value for name sequence 93 * @sseq: pointer to dynamically-sized array of sub-sequences of this 'type'; 94 * sub-sequences are sorted in ascending order 95 * @alloc: number of sub-sequences currently in array 96 * @first_free: array index of first unused sub-sequence entry 97 * @ns_list: links to adjacent name sequences in hash chain 98 * @subscriptions: list of subscriptions for this 'type' 99 * @lock: spinlock controlling access to publication lists of all sub-sequences 100 * @rcu: RCU callback head used for deferred freeing 101 */ 102 struct name_seq { 103 u32 type; 104 struct sub_seq *sseqs; 105 u32 alloc; 106 u32 first_free; 107 struct hlist_node ns_list; 108 struct list_head subscriptions; 109 spinlock_t lock; 110 struct rcu_head rcu; 111 }; 112 113 static int hash(int x) 114 { 115 return x & (TIPC_NAMETBL_SIZE - 1); 116 } 117 118 /** 119 * publ_create - create a publication structure 120 */ 121 static struct publication *publ_create(u32 type, u32 lower, u32 upper, 122 u32 scope, u32 node, u32 port_ref, 123 u32 key) 124 { 125 struct publication *publ = kzalloc(sizeof(*publ), GFP_ATOMIC); 126 if (publ == NULL) { 127 pr_warn("Publication creation failure, no memory\n"); 128 return NULL; 129 } 130 131 publ->type = type; 132 publ->lower = lower; 133 publ->upper = upper; 134 publ->scope = scope; 135 publ->node = node; 136 publ->ref = port_ref; 137 publ->key = key; 138 INIT_LIST_HEAD(&publ->pport_list); 139 return publ; 140 } 141 142 /** 143 * tipc_subseq_alloc - allocate a specified number of sub-sequence structures 144 */ 145 static struct sub_seq *tipc_subseq_alloc(u32 cnt) 146 { 147 return kcalloc(cnt, sizeof(struct sub_seq), GFP_ATOMIC); 148 } 149 150 /** 151 * tipc_nameseq_create - create a name sequence structure for the specified 'type' 152 * 153 * Allocates a single sub-sequence structure and sets it to all 0's. 154 */ 155 static struct name_seq *tipc_nameseq_create(u32 type, struct hlist_head *seq_head) 156 { 157 struct name_seq *nseq = kzalloc(sizeof(*nseq), GFP_ATOMIC); 158 struct sub_seq *sseq = tipc_subseq_alloc(1); 159 160 if (!nseq || !sseq) { 161 pr_warn("Name sequence creation failed, no memory\n"); 162 kfree(nseq); 163 kfree(sseq); 164 return NULL; 165 } 166 167 spin_lock_init(&nseq->lock); 168 nseq->type = type; 169 nseq->sseqs = sseq; 170 nseq->alloc = 1; 171 INIT_HLIST_NODE(&nseq->ns_list); 172 INIT_LIST_HEAD(&nseq->subscriptions); 173 hlist_add_head_rcu(&nseq->ns_list, seq_head); 174 return nseq; 175 } 176 177 /** 178 * nameseq_find_subseq - find sub-sequence (if any) matching a name instance 179 * 180 * Very time-critical, so binary searches through sub-sequence array. 181 */ 182 static struct sub_seq *nameseq_find_subseq(struct name_seq *nseq, 183 u32 instance) 184 { 185 struct sub_seq *sseqs = nseq->sseqs; 186 int low = 0; 187 int high = nseq->first_free - 1; 188 int mid; 189 190 while (low <= high) { 191 mid = (low + high) / 2; 192 if (instance < sseqs[mid].lower) 193 high = mid - 1; 194 else if (instance > sseqs[mid].upper) 195 low = mid + 1; 196 else 197 return &sseqs[mid]; 198 } 199 return NULL; 200 } 201 202 /** 203 * nameseq_locate_subseq - determine position of name instance in sub-sequence 204 * 205 * Returns index in sub-sequence array of the entry that contains the specified 206 * instance value; if no entry contains that value, returns the position 207 * where a new entry for it would be inserted in the array. 208 * 209 * Note: Similar to binary search code for locating a sub-sequence. 210 */ 211 static u32 nameseq_locate_subseq(struct name_seq *nseq, u32 instance) 212 { 213 struct sub_seq *sseqs = nseq->sseqs; 214 int low = 0; 215 int high = nseq->first_free - 1; 216 int mid; 217 218 while (low <= high) { 219 mid = (low + high) / 2; 220 if (instance < sseqs[mid].lower) 221 high = mid - 1; 222 else if (instance > sseqs[mid].upper) 223 low = mid + 1; 224 else 225 return mid; 226 } 227 return low; 228 } 229 230 /** 231 * tipc_nameseq_insert_publ 232 */ 233 static struct publication *tipc_nameseq_insert_publ(struct net *net, 234 struct name_seq *nseq, 235 u32 type, u32 lower, 236 u32 upper, u32 scope, 237 u32 node, u32 port, u32 key) 238 { 239 struct tipc_subscription *s; 240 struct tipc_subscription *st; 241 struct publication *publ; 242 struct sub_seq *sseq; 243 struct name_info *info; 244 int created_subseq = 0; 245 246 sseq = nameseq_find_subseq(nseq, lower); 247 if (sseq) { 248 249 /* Lower end overlaps existing entry => need an exact match */ 250 if ((sseq->lower != lower) || (sseq->upper != upper)) { 251 return NULL; 252 } 253 254 info = sseq->info; 255 256 /* Check if an identical publication already exists */ 257 list_for_each_entry(publ, &info->zone_list, zone_list) { 258 if ((publ->ref == port) && (publ->key == key) && 259 (!publ->node || (publ->node == node))) 260 return NULL; 261 } 262 } else { 263 u32 inspos; 264 struct sub_seq *freesseq; 265 266 /* Find where lower end should be inserted */ 267 inspos = nameseq_locate_subseq(nseq, lower); 268 269 /* Fail if upper end overlaps into an existing entry */ 270 if ((inspos < nseq->first_free) && 271 (upper >= nseq->sseqs[inspos].lower)) { 272 return NULL; 273 } 274 275 /* Ensure there is space for new sub-sequence */ 276 if (nseq->first_free == nseq->alloc) { 277 struct sub_seq *sseqs = tipc_subseq_alloc(nseq->alloc * 2); 278 279 if (!sseqs) { 280 pr_warn("Cannot publish {%u,%u,%u}, no memory\n", 281 type, lower, upper); 282 return NULL; 283 } 284 memcpy(sseqs, nseq->sseqs, 285 nseq->alloc * sizeof(struct sub_seq)); 286 kfree(nseq->sseqs); 287 nseq->sseqs = sseqs; 288 nseq->alloc *= 2; 289 } 290 291 info = kzalloc(sizeof(*info), GFP_ATOMIC); 292 if (!info) { 293 pr_warn("Cannot publish {%u,%u,%u}, no memory\n", 294 type, lower, upper); 295 return NULL; 296 } 297 298 INIT_LIST_HEAD(&info->node_list); 299 INIT_LIST_HEAD(&info->cluster_list); 300 INIT_LIST_HEAD(&info->zone_list); 301 302 /* Insert new sub-sequence */ 303 sseq = &nseq->sseqs[inspos]; 304 freesseq = &nseq->sseqs[nseq->first_free]; 305 memmove(sseq + 1, sseq, (freesseq - sseq) * sizeof(*sseq)); 306 memset(sseq, 0, sizeof(*sseq)); 307 nseq->first_free++; 308 sseq->lower = lower; 309 sseq->upper = upper; 310 sseq->info = info; 311 created_subseq = 1; 312 } 313 314 /* Insert a publication */ 315 publ = publ_create(type, lower, upper, scope, node, port, key); 316 if (!publ) 317 return NULL; 318 319 list_add(&publ->zone_list, &info->zone_list); 320 info->zone_list_size++; 321 322 if (in_own_cluster(net, node)) { 323 list_add(&publ->cluster_list, &info->cluster_list); 324 info->cluster_list_size++; 325 } 326 327 if (in_own_node(net, node)) { 328 list_add(&publ->node_list, &info->node_list); 329 info->node_list_size++; 330 } 331 332 /* Any subscriptions waiting for notification? */ 333 list_for_each_entry_safe(s, st, &nseq->subscriptions, nameseq_list) { 334 tipc_subscrp_report_overlap(s, publ->lower, publ->upper, 335 TIPC_PUBLISHED, publ->ref, 336 publ->node, created_subseq); 337 } 338 return publ; 339 } 340 341 /** 342 * tipc_nameseq_remove_publ 343 * 344 * NOTE: There may be cases where TIPC is asked to remove a publication 345 * that is not in the name table. For example, if another node issues a 346 * publication for a name sequence that overlaps an existing name sequence 347 * the publication will not be recorded, which means the publication won't 348 * be found when the name sequence is later withdrawn by that node. 349 * A failed withdraw request simply returns a failure indication and lets the 350 * caller issue any error or warning messages associated with such a problem. 351 */ 352 static struct publication *tipc_nameseq_remove_publ(struct net *net, 353 struct name_seq *nseq, 354 u32 inst, u32 node, 355 u32 ref, u32 key) 356 { 357 struct publication *publ; 358 struct sub_seq *sseq = nameseq_find_subseq(nseq, inst); 359 struct name_info *info; 360 struct sub_seq *free; 361 struct tipc_subscription *s, *st; 362 int removed_subseq = 0; 363 364 if (!sseq) 365 return NULL; 366 367 info = sseq->info; 368 369 /* Locate publication, if it exists */ 370 list_for_each_entry(publ, &info->zone_list, zone_list) { 371 if ((publ->key == key) && (publ->ref == ref) && 372 (!publ->node || (publ->node == node))) 373 goto found; 374 } 375 return NULL; 376 377 found: 378 /* Remove publication from zone scope list */ 379 list_del(&publ->zone_list); 380 info->zone_list_size--; 381 382 /* Remove publication from cluster scope list, if present */ 383 if (in_own_cluster(net, node)) { 384 list_del(&publ->cluster_list); 385 info->cluster_list_size--; 386 } 387 388 /* Remove publication from node scope list, if present */ 389 if (in_own_node(net, node)) { 390 list_del(&publ->node_list); 391 info->node_list_size--; 392 } 393 394 /* Contract subseq list if no more publications for that subseq */ 395 if (list_empty(&info->zone_list)) { 396 kfree(info); 397 free = &nseq->sseqs[nseq->first_free--]; 398 memmove(sseq, sseq + 1, (free - (sseq + 1)) * sizeof(*sseq)); 399 removed_subseq = 1; 400 } 401 402 /* Notify any waiting subscriptions */ 403 list_for_each_entry_safe(s, st, &nseq->subscriptions, nameseq_list) { 404 tipc_subscrp_report_overlap(s, publ->lower, publ->upper, 405 TIPC_WITHDRAWN, publ->ref, 406 publ->node, removed_subseq); 407 } 408 409 return publ; 410 } 411 412 /** 413 * tipc_nameseq_subscribe - attach a subscription, and issue 414 * the prescribed number of events if there is any sub- 415 * sequence overlapping with the requested sequence 416 */ 417 static void tipc_nameseq_subscribe(struct name_seq *nseq, 418 struct tipc_subscription *s) 419 { 420 struct sub_seq *sseq = nseq->sseqs; 421 struct tipc_name_seq ns; 422 423 tipc_subscrp_convert_seq(&s->evt.s.seq, s->swap, &ns); 424 425 list_add(&s->nameseq_list, &nseq->subscriptions); 426 427 if (!sseq) 428 return; 429 430 while (sseq != &nseq->sseqs[nseq->first_free]) { 431 if (tipc_subscrp_check_overlap(&ns, sseq->lower, sseq->upper)) { 432 struct publication *crs; 433 struct name_info *info = sseq->info; 434 int must_report = 1; 435 436 list_for_each_entry(crs, &info->zone_list, zone_list) { 437 tipc_subscrp_report_overlap(s, sseq->lower, 438 sseq->upper, 439 TIPC_PUBLISHED, 440 crs->ref, crs->node, 441 must_report); 442 must_report = 0; 443 } 444 } 445 sseq++; 446 } 447 } 448 449 static struct name_seq *nametbl_find_seq(struct net *net, u32 type) 450 { 451 struct tipc_net *tn = net_generic(net, tipc_net_id); 452 struct hlist_head *seq_head; 453 struct name_seq *ns; 454 455 seq_head = &tn->nametbl->seq_hlist[hash(type)]; 456 hlist_for_each_entry_rcu(ns, seq_head, ns_list) { 457 if (ns->type == type) 458 return ns; 459 } 460 461 return NULL; 462 }; 463 464 struct publication *tipc_nametbl_insert_publ(struct net *net, u32 type, 465 u32 lower, u32 upper, u32 scope, 466 u32 node, u32 port, u32 key) 467 { 468 struct tipc_net *tn = net_generic(net, tipc_net_id); 469 struct publication *publ; 470 struct name_seq *seq = nametbl_find_seq(net, type); 471 int index = hash(type); 472 473 if ((scope < TIPC_ZONE_SCOPE) || (scope > TIPC_NODE_SCOPE) || 474 (lower > upper)) { 475 pr_debug("Failed to publish illegal {%u,%u,%u} with scope %u\n", 476 type, lower, upper, scope); 477 return NULL; 478 } 479 480 if (!seq) 481 seq = tipc_nameseq_create(type, &tn->nametbl->seq_hlist[index]); 482 if (!seq) 483 return NULL; 484 485 spin_lock_bh(&seq->lock); 486 publ = tipc_nameseq_insert_publ(net, seq, type, lower, upper, 487 scope, node, port, key); 488 spin_unlock_bh(&seq->lock); 489 return publ; 490 } 491 492 struct publication *tipc_nametbl_remove_publ(struct net *net, u32 type, 493 u32 lower, u32 node, u32 ref, 494 u32 key) 495 { 496 struct publication *publ; 497 struct name_seq *seq = nametbl_find_seq(net, type); 498 499 if (!seq) 500 return NULL; 501 502 spin_lock_bh(&seq->lock); 503 publ = tipc_nameseq_remove_publ(net, seq, lower, node, ref, key); 504 if (!seq->first_free && list_empty(&seq->subscriptions)) { 505 hlist_del_init_rcu(&seq->ns_list); 506 kfree(seq->sseqs); 507 spin_unlock_bh(&seq->lock); 508 kfree_rcu(seq, rcu); 509 return publ; 510 } 511 spin_unlock_bh(&seq->lock); 512 return publ; 513 } 514 515 /** 516 * tipc_nametbl_translate - perform name translation 517 * 518 * On entry, 'destnode' is the search domain used during translation. 519 * 520 * On exit: 521 * - if name translation is deferred to another node/cluster/zone, 522 * leaves 'destnode' unchanged (will be non-zero) and returns 0 523 * - if name translation is attempted and succeeds, sets 'destnode' 524 * to publishing node and returns port reference (will be non-zero) 525 * - if name translation is attempted and fails, sets 'destnode' to 0 526 * and returns 0 527 */ 528 u32 tipc_nametbl_translate(struct net *net, u32 type, u32 instance, 529 u32 *destnode) 530 { 531 struct tipc_net *tn = net_generic(net, tipc_net_id); 532 struct sub_seq *sseq; 533 struct name_info *info; 534 struct publication *publ; 535 struct name_seq *seq; 536 u32 ref = 0; 537 u32 node = 0; 538 539 if (!tipc_in_scope(*destnode, tn->own_addr)) 540 return 0; 541 542 rcu_read_lock(); 543 seq = nametbl_find_seq(net, type); 544 if (unlikely(!seq)) 545 goto not_found; 546 spin_lock_bh(&seq->lock); 547 sseq = nameseq_find_subseq(seq, instance); 548 if (unlikely(!sseq)) 549 goto no_match; 550 info = sseq->info; 551 552 /* Closest-First Algorithm */ 553 if (likely(!*destnode)) { 554 if (!list_empty(&info->node_list)) { 555 publ = list_first_entry(&info->node_list, 556 struct publication, 557 node_list); 558 list_move_tail(&publ->node_list, 559 &info->node_list); 560 } else if (!list_empty(&info->cluster_list)) { 561 publ = list_first_entry(&info->cluster_list, 562 struct publication, 563 cluster_list); 564 list_move_tail(&publ->cluster_list, 565 &info->cluster_list); 566 } else { 567 publ = list_first_entry(&info->zone_list, 568 struct publication, 569 zone_list); 570 list_move_tail(&publ->zone_list, 571 &info->zone_list); 572 } 573 } 574 575 /* Round-Robin Algorithm */ 576 else if (*destnode == tn->own_addr) { 577 if (list_empty(&info->node_list)) 578 goto no_match; 579 publ = list_first_entry(&info->node_list, struct publication, 580 node_list); 581 list_move_tail(&publ->node_list, &info->node_list); 582 } else if (in_own_cluster_exact(net, *destnode)) { 583 if (list_empty(&info->cluster_list)) 584 goto no_match; 585 publ = list_first_entry(&info->cluster_list, struct publication, 586 cluster_list); 587 list_move_tail(&publ->cluster_list, &info->cluster_list); 588 } else { 589 publ = list_first_entry(&info->zone_list, struct publication, 590 zone_list); 591 list_move_tail(&publ->zone_list, &info->zone_list); 592 } 593 594 ref = publ->ref; 595 node = publ->node; 596 no_match: 597 spin_unlock_bh(&seq->lock); 598 not_found: 599 rcu_read_unlock(); 600 *destnode = node; 601 return ref; 602 } 603 604 /** 605 * tipc_nametbl_mc_translate - find multicast destinations 606 * 607 * Creates list of all local ports that overlap the given multicast address; 608 * also determines if any off-node ports overlap. 609 * 610 * Note: Publications with a scope narrower than 'limit' are ignored. 611 * (i.e. local node-scope publications mustn't receive messages arriving 612 * from another node, even if the multcast link brought it here) 613 * 614 * Returns non-zero if any off-node ports overlap 615 */ 616 int tipc_nametbl_mc_translate(struct net *net, u32 type, u32 lower, u32 upper, 617 u32 limit, struct tipc_plist *dports) 618 { 619 struct name_seq *seq; 620 struct sub_seq *sseq; 621 struct sub_seq *sseq_stop; 622 struct name_info *info; 623 int res = 0; 624 625 rcu_read_lock(); 626 seq = nametbl_find_seq(net, type); 627 if (!seq) 628 goto exit; 629 630 spin_lock_bh(&seq->lock); 631 sseq = seq->sseqs + nameseq_locate_subseq(seq, lower); 632 sseq_stop = seq->sseqs + seq->first_free; 633 for (; sseq != sseq_stop; sseq++) { 634 struct publication *publ; 635 636 if (sseq->lower > upper) 637 break; 638 639 info = sseq->info; 640 list_for_each_entry(publ, &info->node_list, node_list) { 641 if (publ->scope <= limit) 642 tipc_plist_push(dports, publ->ref); 643 } 644 645 if (info->cluster_list_size != info->node_list_size) 646 res = 1; 647 } 648 spin_unlock_bh(&seq->lock); 649 exit: 650 rcu_read_unlock(); 651 return res; 652 } 653 654 /* 655 * tipc_nametbl_publish - add name publication to network name tables 656 */ 657 struct publication *tipc_nametbl_publish(struct net *net, u32 type, u32 lower, 658 u32 upper, u32 scope, u32 port_ref, 659 u32 key) 660 { 661 struct publication *publ; 662 struct sk_buff *buf = NULL; 663 struct tipc_net *tn = net_generic(net, tipc_net_id); 664 665 spin_lock_bh(&tn->nametbl_lock); 666 if (tn->nametbl->local_publ_count >= TIPC_MAX_PUBLICATIONS) { 667 pr_warn("Publication failed, local publication limit reached (%u)\n", 668 TIPC_MAX_PUBLICATIONS); 669 spin_unlock_bh(&tn->nametbl_lock); 670 return NULL; 671 } 672 673 publ = tipc_nametbl_insert_publ(net, type, lower, upper, scope, 674 tn->own_addr, port_ref, key); 675 if (likely(publ)) { 676 tn->nametbl->local_publ_count++; 677 buf = tipc_named_publish(net, publ); 678 /* Any pending external events? */ 679 tipc_named_process_backlog(net); 680 } 681 spin_unlock_bh(&tn->nametbl_lock); 682 683 if (buf) 684 tipc_node_broadcast(net, buf); 685 return publ; 686 } 687 688 /** 689 * tipc_nametbl_withdraw - withdraw name publication from network name tables 690 */ 691 int tipc_nametbl_withdraw(struct net *net, u32 type, u32 lower, u32 ref, 692 u32 key) 693 { 694 struct publication *publ; 695 struct sk_buff *skb = NULL; 696 struct tipc_net *tn = net_generic(net, tipc_net_id); 697 698 spin_lock_bh(&tn->nametbl_lock); 699 publ = tipc_nametbl_remove_publ(net, type, lower, tn->own_addr, 700 ref, key); 701 if (likely(publ)) { 702 tn->nametbl->local_publ_count--; 703 skb = tipc_named_withdraw(net, publ); 704 /* Any pending external events? */ 705 tipc_named_process_backlog(net); 706 list_del_init(&publ->pport_list); 707 kfree_rcu(publ, rcu); 708 } else { 709 pr_err("Unable to remove local publication\n" 710 "(type=%u, lower=%u, ref=%u, key=%u)\n", 711 type, lower, ref, key); 712 } 713 spin_unlock_bh(&tn->nametbl_lock); 714 715 if (skb) { 716 tipc_node_broadcast(net, skb); 717 return 1; 718 } 719 return 0; 720 } 721 722 /** 723 * tipc_nametbl_subscribe - add a subscription object to the name table 724 */ 725 void tipc_nametbl_subscribe(struct tipc_subscription *s) 726 { 727 struct tipc_net *tn = net_generic(s->net, tipc_net_id); 728 u32 type = tipc_subscrp_convert_seq_type(s->evt.s.seq.type, s->swap); 729 int index = hash(type); 730 struct name_seq *seq; 731 struct tipc_name_seq ns; 732 733 spin_lock_bh(&tn->nametbl_lock); 734 seq = nametbl_find_seq(s->net, type); 735 if (!seq) 736 seq = tipc_nameseq_create(type, &tn->nametbl->seq_hlist[index]); 737 if (seq) { 738 spin_lock_bh(&seq->lock); 739 tipc_nameseq_subscribe(seq, s); 740 spin_unlock_bh(&seq->lock); 741 } else { 742 tipc_subscrp_convert_seq(&s->evt.s.seq, s->swap, &ns); 743 pr_warn("Failed to create subscription for {%u,%u,%u}\n", 744 ns.type, ns.lower, ns.upper); 745 } 746 spin_unlock_bh(&tn->nametbl_lock); 747 } 748 749 /** 750 * tipc_nametbl_unsubscribe - remove a subscription object from name table 751 */ 752 void tipc_nametbl_unsubscribe(struct tipc_subscription *s) 753 { 754 struct tipc_net *tn = net_generic(s->net, tipc_net_id); 755 struct name_seq *seq; 756 u32 type = tipc_subscrp_convert_seq_type(s->evt.s.seq.type, s->swap); 757 758 spin_lock_bh(&tn->nametbl_lock); 759 seq = nametbl_find_seq(s->net, type); 760 if (seq != NULL) { 761 spin_lock_bh(&seq->lock); 762 list_del_init(&s->nameseq_list); 763 if (!seq->first_free && list_empty(&seq->subscriptions)) { 764 hlist_del_init_rcu(&seq->ns_list); 765 kfree(seq->sseqs); 766 spin_unlock_bh(&seq->lock); 767 kfree_rcu(seq, rcu); 768 } else { 769 spin_unlock_bh(&seq->lock); 770 } 771 } 772 spin_unlock_bh(&tn->nametbl_lock); 773 } 774 775 int tipc_nametbl_init(struct net *net) 776 { 777 struct tipc_net *tn = net_generic(net, tipc_net_id); 778 struct name_table *tipc_nametbl; 779 int i; 780 781 tipc_nametbl = kzalloc(sizeof(*tipc_nametbl), GFP_ATOMIC); 782 if (!tipc_nametbl) 783 return -ENOMEM; 784 785 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) 786 INIT_HLIST_HEAD(&tipc_nametbl->seq_hlist[i]); 787 788 INIT_LIST_HEAD(&tipc_nametbl->publ_list[TIPC_ZONE_SCOPE]); 789 INIT_LIST_HEAD(&tipc_nametbl->publ_list[TIPC_CLUSTER_SCOPE]); 790 INIT_LIST_HEAD(&tipc_nametbl->publ_list[TIPC_NODE_SCOPE]); 791 tn->nametbl = tipc_nametbl; 792 spin_lock_init(&tn->nametbl_lock); 793 return 0; 794 } 795 796 /** 797 * tipc_purge_publications - remove all publications for a given type 798 * 799 * tipc_nametbl_lock must be held when calling this function 800 */ 801 static void tipc_purge_publications(struct net *net, struct name_seq *seq) 802 { 803 struct publication *publ, *safe; 804 struct sub_seq *sseq; 805 struct name_info *info; 806 807 spin_lock_bh(&seq->lock); 808 sseq = seq->sseqs; 809 info = sseq->info; 810 list_for_each_entry_safe(publ, safe, &info->zone_list, zone_list) { 811 tipc_nameseq_remove_publ(net, seq, publ->lower, publ->node, 812 publ->ref, publ->key); 813 kfree_rcu(publ, rcu); 814 } 815 hlist_del_init_rcu(&seq->ns_list); 816 kfree(seq->sseqs); 817 spin_unlock_bh(&seq->lock); 818 819 kfree_rcu(seq, rcu); 820 } 821 822 void tipc_nametbl_stop(struct net *net) 823 { 824 u32 i; 825 struct name_seq *seq; 826 struct hlist_head *seq_head; 827 struct tipc_net *tn = net_generic(net, tipc_net_id); 828 struct name_table *tipc_nametbl = tn->nametbl; 829 830 /* Verify name table is empty and purge any lingering 831 * publications, then release the name table 832 */ 833 spin_lock_bh(&tn->nametbl_lock); 834 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) { 835 if (hlist_empty(&tipc_nametbl->seq_hlist[i])) 836 continue; 837 seq_head = &tipc_nametbl->seq_hlist[i]; 838 hlist_for_each_entry_rcu(seq, seq_head, ns_list) { 839 tipc_purge_publications(net, seq); 840 } 841 } 842 spin_unlock_bh(&tn->nametbl_lock); 843 844 synchronize_net(); 845 kfree(tipc_nametbl); 846 847 } 848 849 static int __tipc_nl_add_nametable_publ(struct tipc_nl_msg *msg, 850 struct name_seq *seq, 851 struct sub_seq *sseq, u32 *last_publ) 852 { 853 void *hdr; 854 struct nlattr *attrs; 855 struct nlattr *publ; 856 struct publication *p; 857 858 if (*last_publ) { 859 list_for_each_entry(p, &sseq->info->zone_list, zone_list) 860 if (p->key == *last_publ) 861 break; 862 if (p->key != *last_publ) 863 return -EPIPE; 864 } else { 865 p = list_first_entry(&sseq->info->zone_list, struct publication, 866 zone_list); 867 } 868 869 list_for_each_entry_from(p, &sseq->info->zone_list, zone_list) { 870 *last_publ = p->key; 871 872 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, 873 &tipc_genl_family, NLM_F_MULTI, 874 TIPC_NL_NAME_TABLE_GET); 875 if (!hdr) 876 return -EMSGSIZE; 877 878 attrs = nla_nest_start(msg->skb, TIPC_NLA_NAME_TABLE); 879 if (!attrs) 880 goto msg_full; 881 882 publ = nla_nest_start(msg->skb, TIPC_NLA_NAME_TABLE_PUBL); 883 if (!publ) 884 goto attr_msg_full; 885 886 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_TYPE, seq->type)) 887 goto publ_msg_full; 888 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_LOWER, sseq->lower)) 889 goto publ_msg_full; 890 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_UPPER, sseq->upper)) 891 goto publ_msg_full; 892 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_SCOPE, p->scope)) 893 goto publ_msg_full; 894 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_NODE, p->node)) 895 goto publ_msg_full; 896 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_REF, p->ref)) 897 goto publ_msg_full; 898 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_KEY, p->key)) 899 goto publ_msg_full; 900 901 nla_nest_end(msg->skb, publ); 902 nla_nest_end(msg->skb, attrs); 903 genlmsg_end(msg->skb, hdr); 904 } 905 *last_publ = 0; 906 907 return 0; 908 909 publ_msg_full: 910 nla_nest_cancel(msg->skb, publ); 911 attr_msg_full: 912 nla_nest_cancel(msg->skb, attrs); 913 msg_full: 914 genlmsg_cancel(msg->skb, hdr); 915 916 return -EMSGSIZE; 917 } 918 919 static int __tipc_nl_subseq_list(struct tipc_nl_msg *msg, struct name_seq *seq, 920 u32 *last_lower, u32 *last_publ) 921 { 922 struct sub_seq *sseq; 923 struct sub_seq *sseq_start; 924 int err; 925 926 if (*last_lower) { 927 sseq_start = nameseq_find_subseq(seq, *last_lower); 928 if (!sseq_start) 929 return -EPIPE; 930 } else { 931 sseq_start = seq->sseqs; 932 } 933 934 for (sseq = sseq_start; sseq != &seq->sseqs[seq->first_free]; sseq++) { 935 err = __tipc_nl_add_nametable_publ(msg, seq, sseq, last_publ); 936 if (err) { 937 *last_lower = sseq->lower; 938 return err; 939 } 940 } 941 *last_lower = 0; 942 943 return 0; 944 } 945 946 static int tipc_nl_seq_list(struct net *net, struct tipc_nl_msg *msg, 947 u32 *last_type, u32 *last_lower, u32 *last_publ) 948 { 949 struct tipc_net *tn = net_generic(net, tipc_net_id); 950 struct hlist_head *seq_head; 951 struct name_seq *seq = NULL; 952 int err; 953 int i; 954 955 if (*last_type) 956 i = hash(*last_type); 957 else 958 i = 0; 959 960 for (; i < TIPC_NAMETBL_SIZE; i++) { 961 seq_head = &tn->nametbl->seq_hlist[i]; 962 963 if (*last_type) { 964 seq = nametbl_find_seq(net, *last_type); 965 if (!seq) 966 return -EPIPE; 967 } else { 968 hlist_for_each_entry_rcu(seq, seq_head, ns_list) 969 break; 970 if (!seq) 971 continue; 972 } 973 974 hlist_for_each_entry_from_rcu(seq, ns_list) { 975 spin_lock_bh(&seq->lock); 976 err = __tipc_nl_subseq_list(msg, seq, last_lower, 977 last_publ); 978 979 if (err) { 980 *last_type = seq->type; 981 spin_unlock_bh(&seq->lock); 982 return err; 983 } 984 spin_unlock_bh(&seq->lock); 985 } 986 *last_type = 0; 987 } 988 return 0; 989 } 990 991 int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb) 992 { 993 int err; 994 int done = cb->args[3]; 995 u32 last_type = cb->args[0]; 996 u32 last_lower = cb->args[1]; 997 u32 last_publ = cb->args[2]; 998 struct net *net = sock_net(skb->sk); 999 struct tipc_nl_msg msg; 1000 1001 if (done) 1002 return 0; 1003 1004 msg.skb = skb; 1005 msg.portid = NETLINK_CB(cb->skb).portid; 1006 msg.seq = cb->nlh->nlmsg_seq; 1007 1008 rcu_read_lock(); 1009 err = tipc_nl_seq_list(net, &msg, &last_type, &last_lower, &last_publ); 1010 if (!err) { 1011 done = 1; 1012 } else if (err != -EMSGSIZE) { 1013 /* We never set seq or call nl_dump_check_consistent() this 1014 * means that setting prev_seq here will cause the consistence 1015 * check to fail in the netlink callback handler. Resulting in 1016 * the NLMSG_DONE message having the NLM_F_DUMP_INTR flag set if 1017 * we got an error. 1018 */ 1019 cb->prev_seq = 1; 1020 } 1021 rcu_read_unlock(); 1022 1023 cb->args[0] = last_type; 1024 cb->args[1] = last_lower; 1025 cb->args[2] = last_publ; 1026 cb->args[3] = done; 1027 1028 return skb->len; 1029 } 1030 1031 void tipc_plist_push(struct tipc_plist *pl, u32 port) 1032 { 1033 struct tipc_plist *nl; 1034 1035 if (likely(!pl->port)) { 1036 pl->port = port; 1037 return; 1038 } 1039 if (pl->port == port) 1040 return; 1041 list_for_each_entry(nl, &pl->list, list) { 1042 if (nl->port == port) 1043 return; 1044 } 1045 nl = kmalloc(sizeof(*nl), GFP_ATOMIC); 1046 if (nl) { 1047 nl->port = port; 1048 list_add(&nl->list, &pl->list); 1049 } 1050 } 1051 1052 u32 tipc_plist_pop(struct tipc_plist *pl) 1053 { 1054 struct tipc_plist *nl; 1055 u32 port = 0; 1056 1057 if (likely(list_empty(&pl->list))) { 1058 port = pl->port; 1059 pl->port = 0; 1060 return port; 1061 } 1062 nl = list_first_entry(&pl->list, typeof(*nl), list); 1063 port = nl->port; 1064 list_del(&nl->list); 1065 kfree(nl); 1066 return port; 1067 } 1068