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