1 /* 2 * net/tipc/name_table.c: TIPC name table code 3 * 4 * Copyright (c) 2000-2006, 2014-2018, 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 "group.h" 47 #include <net/genetlink.h> 48 49 #define TIPC_NAMETBL_SIZE 1024 /* must be a power of 2 */ 50 51 /** 52 * struct name_info - name sequence publication info 53 * @node_list: list of publications on own node of this <type,lower,upper> 54 * @all_publ: list of all publications of this <type,lower,upper> 55 */ 56 struct name_info { 57 struct list_head local_publ; 58 struct list_head all_publ; 59 }; 60 61 /** 62 * struct sub_seq - container for all published instances of a name sequence 63 * @lower: name sequence lower bound 64 * @upper: name sequence upper bound 65 * @info: pointer to name sequence publication info 66 */ 67 struct sub_seq { 68 u32 lower; 69 u32 upper; 70 struct name_info *info; 71 }; 72 73 /** 74 * struct name_seq - container for all published instances of a name type 75 * @type: 32 bit 'type' value for name sequence 76 * @sseq: pointer to dynamically-sized array of sub-sequences of this 'type'; 77 * sub-sequences are sorted in ascending order 78 * @alloc: number of sub-sequences currently in array 79 * @first_free: array index of first unused sub-sequence entry 80 * @ns_list: links to adjacent name sequences in hash chain 81 * @subscriptions: list of subscriptions for this 'type' 82 * @lock: spinlock controlling access to publication lists of all sub-sequences 83 * @rcu: RCU callback head used for deferred freeing 84 */ 85 struct name_seq { 86 u32 type; 87 struct sub_seq *sseqs; 88 u32 alloc; 89 u32 first_free; 90 struct hlist_node ns_list; 91 struct list_head subscriptions; 92 spinlock_t lock; 93 struct rcu_head rcu; 94 }; 95 96 static int hash(int x) 97 { 98 return x & (TIPC_NAMETBL_SIZE - 1); 99 } 100 101 /** 102 * publ_create - create a publication structure 103 */ 104 static struct publication *publ_create(u32 type, u32 lower, u32 upper, 105 u32 scope, u32 node, u32 port, 106 u32 key) 107 { 108 struct publication *publ = kzalloc(sizeof(*publ), GFP_ATOMIC); 109 if (publ == NULL) { 110 pr_warn("Publication creation failure, no memory\n"); 111 return NULL; 112 } 113 114 publ->type = type; 115 publ->lower = lower; 116 publ->upper = upper; 117 publ->scope = scope; 118 publ->node = node; 119 publ->port = port; 120 publ->key = key; 121 INIT_LIST_HEAD(&publ->binding_sock); 122 return publ; 123 } 124 125 /** 126 * tipc_subseq_alloc - allocate a specified number of sub-sequence structures 127 */ 128 static struct sub_seq *tipc_subseq_alloc(u32 cnt) 129 { 130 return kcalloc(cnt, sizeof(struct sub_seq), GFP_ATOMIC); 131 } 132 133 /** 134 * tipc_nameseq_create - create a name sequence structure for the specified 'type' 135 * 136 * Allocates a single sub-sequence structure and sets it to all 0's. 137 */ 138 static struct name_seq *tipc_nameseq_create(u32 type, struct hlist_head *seq_head) 139 { 140 struct name_seq *nseq = kzalloc(sizeof(*nseq), GFP_ATOMIC); 141 struct sub_seq *sseq = tipc_subseq_alloc(1); 142 143 if (!nseq || !sseq) { 144 pr_warn("Name sequence creation failed, no memory\n"); 145 kfree(nseq); 146 kfree(sseq); 147 return NULL; 148 } 149 150 spin_lock_init(&nseq->lock); 151 nseq->type = type; 152 nseq->sseqs = sseq; 153 nseq->alloc = 1; 154 INIT_HLIST_NODE(&nseq->ns_list); 155 INIT_LIST_HEAD(&nseq->subscriptions); 156 hlist_add_head_rcu(&nseq->ns_list, seq_head); 157 return nseq; 158 } 159 160 /** 161 * nameseq_find_subseq - find sub-sequence (if any) matching a name instance 162 * 163 * Very time-critical, so binary searches through sub-sequence array. 164 */ 165 static struct sub_seq *nameseq_find_subseq(struct name_seq *nseq, 166 u32 instance) 167 { 168 struct sub_seq *sseqs = nseq->sseqs; 169 int low = 0; 170 int high = nseq->first_free - 1; 171 int mid; 172 173 while (low <= high) { 174 mid = (low + high) / 2; 175 if (instance < sseqs[mid].lower) 176 high = mid - 1; 177 else if (instance > sseqs[mid].upper) 178 low = mid + 1; 179 else 180 return &sseqs[mid]; 181 } 182 return NULL; 183 } 184 185 /** 186 * nameseq_locate_subseq - determine position of name instance in sub-sequence 187 * 188 * Returns index in sub-sequence array of the entry that contains the specified 189 * instance value; if no entry contains that value, returns the position 190 * where a new entry for it would be inserted in the array. 191 * 192 * Note: Similar to binary search code for locating a sub-sequence. 193 */ 194 static u32 nameseq_locate_subseq(struct name_seq *nseq, u32 instance) 195 { 196 struct sub_seq *sseqs = nseq->sseqs; 197 int low = 0; 198 int high = nseq->first_free - 1; 199 int mid; 200 201 while (low <= high) { 202 mid = (low + high) / 2; 203 if (instance < sseqs[mid].lower) 204 high = mid - 1; 205 else if (instance > sseqs[mid].upper) 206 low = mid + 1; 207 else 208 return mid; 209 } 210 return low; 211 } 212 213 /** 214 * tipc_nameseq_insert_publ 215 */ 216 static struct publication *tipc_nameseq_insert_publ(struct net *net, 217 struct name_seq *nseq, 218 u32 type, u32 lower, 219 u32 upper, u32 scope, 220 u32 node, u32 port, u32 key) 221 { 222 struct tipc_subscription *s; 223 struct tipc_subscription *st; 224 struct publication *publ; 225 struct sub_seq *sseq; 226 struct name_info *info; 227 int created_subseq = 0; 228 229 sseq = nameseq_find_subseq(nseq, lower); 230 if (sseq) { 231 232 /* Lower end overlaps existing entry => need an exact match */ 233 if ((sseq->lower != lower) || (sseq->upper != upper)) { 234 return NULL; 235 } 236 237 info = sseq->info; 238 239 /* Check if an identical publication already exists */ 240 list_for_each_entry(publ, &info->all_publ, all_publ) { 241 if (publ->port == port && publ->key == key && 242 (!publ->node || publ->node == node)) 243 return NULL; 244 } 245 } else { 246 u32 inspos; 247 struct sub_seq *freesseq; 248 249 /* Find where lower end should be inserted */ 250 inspos = nameseq_locate_subseq(nseq, lower); 251 252 /* Fail if upper end overlaps into an existing entry */ 253 if ((inspos < nseq->first_free) && 254 (upper >= nseq->sseqs[inspos].lower)) { 255 return NULL; 256 } 257 258 /* Ensure there is space for new sub-sequence */ 259 if (nseq->first_free == nseq->alloc) { 260 struct sub_seq *sseqs = tipc_subseq_alloc(nseq->alloc * 2); 261 262 if (!sseqs) { 263 pr_warn("Cannot publish {%u,%u,%u}, no memory\n", 264 type, lower, upper); 265 return NULL; 266 } 267 memcpy(sseqs, nseq->sseqs, 268 nseq->alloc * sizeof(struct sub_seq)); 269 kfree(nseq->sseqs); 270 nseq->sseqs = sseqs; 271 nseq->alloc *= 2; 272 } 273 274 info = kzalloc(sizeof(*info), GFP_ATOMIC); 275 if (!info) { 276 pr_warn("Cannot publish {%u,%u,%u}, no memory\n", 277 type, lower, upper); 278 return NULL; 279 } 280 281 INIT_LIST_HEAD(&info->local_publ); 282 INIT_LIST_HEAD(&info->all_publ); 283 284 /* Insert new sub-sequence */ 285 sseq = &nseq->sseqs[inspos]; 286 freesseq = &nseq->sseqs[nseq->first_free]; 287 memmove(sseq + 1, sseq, (freesseq - sseq) * sizeof(*sseq)); 288 memset(sseq, 0, sizeof(*sseq)); 289 nseq->first_free++; 290 sseq->lower = lower; 291 sseq->upper = upper; 292 sseq->info = info; 293 created_subseq = 1; 294 } 295 296 /* Insert a publication */ 297 publ = publ_create(type, lower, upper, scope, node, port, key); 298 if (!publ) 299 return NULL; 300 301 list_add(&publ->all_publ, &info->all_publ); 302 303 if (in_own_node(net, node)) 304 list_add(&publ->local_publ, &info->local_publ); 305 306 /* Any subscriptions waiting for notification? */ 307 list_for_each_entry_safe(s, st, &nseq->subscriptions, nameseq_list) { 308 tipc_sub_report_overlap(s, publ->lower, publ->upper, 309 TIPC_PUBLISHED, publ->port, 310 publ->node, publ->scope, 311 created_subseq); 312 } 313 return publ; 314 } 315 316 /** 317 * tipc_nameseq_remove_publ 318 * 319 * NOTE: There may be cases where TIPC is asked to remove a publication 320 * that is not in the name table. For example, if another node issues a 321 * publication for a name sequence that overlaps an existing name sequence 322 * the publication will not be recorded, which means the publication won't 323 * be found when the name sequence is later withdrawn by that node. 324 * A failed withdraw request simply returns a failure indication and lets the 325 * caller issue any error or warning messages associated with such a problem. 326 */ 327 static struct publication *tipc_nameseq_remove_publ(struct net *net, 328 struct name_seq *nseq, 329 u32 inst, u32 node, 330 u32 port, u32 key) 331 { 332 struct publication *publ; 333 struct sub_seq *sseq = nameseq_find_subseq(nseq, inst); 334 struct name_info *info; 335 struct sub_seq *free; 336 struct tipc_subscription *s, *st; 337 int removed_subseq = 0; 338 339 if (!sseq) 340 return NULL; 341 342 info = sseq->info; 343 344 /* Locate publication, if it exists */ 345 list_for_each_entry(publ, &info->all_publ, all_publ) { 346 if (publ->key == key && publ->port == port && 347 (!publ->node || publ->node == node)) 348 goto found; 349 } 350 return NULL; 351 352 found: 353 list_del(&publ->all_publ); 354 if (in_own_node(net, node)) 355 list_del(&publ->local_publ); 356 357 /* Contract subseq list if no more publications for that subseq */ 358 if (list_empty(&info->all_publ)) { 359 kfree(info); 360 free = &nseq->sseqs[nseq->first_free--]; 361 memmove(sseq, sseq + 1, (free - (sseq + 1)) * sizeof(*sseq)); 362 removed_subseq = 1; 363 } 364 365 /* Notify any waiting subscriptions */ 366 list_for_each_entry_safe(s, st, &nseq->subscriptions, nameseq_list) { 367 tipc_sub_report_overlap(s, publ->lower, publ->upper, 368 TIPC_WITHDRAWN, publ->port, 369 publ->node, publ->scope, 370 removed_subseq); 371 } 372 373 return publ; 374 } 375 376 /** 377 * tipc_nameseq_subscribe - attach a subscription, and optionally 378 * issue the prescribed number of events if there is any sub- 379 * sequence overlapping with the requested sequence 380 */ 381 static void tipc_nameseq_subscribe(struct name_seq *nseq, 382 struct tipc_subscription *sub) 383 { 384 struct sub_seq *sseq = nseq->sseqs; 385 struct tipc_name_seq ns; 386 struct tipc_subscr *s = &sub->evt.s; 387 bool no_status; 388 389 ns.type = tipc_sub_read(s, seq.type); 390 ns.lower = tipc_sub_read(s, seq.lower); 391 ns.upper = tipc_sub_read(s, seq.upper); 392 no_status = tipc_sub_read(s, filter) & TIPC_SUB_NO_STATUS; 393 394 tipc_sub_get(sub); 395 list_add(&sub->nameseq_list, &nseq->subscriptions); 396 397 if (no_status || !sseq) 398 return; 399 400 while (sseq != &nseq->sseqs[nseq->first_free]) { 401 if (tipc_sub_check_overlap(&ns, sseq->lower, sseq->upper)) { 402 struct publication *crs; 403 struct name_info *info = sseq->info; 404 int must_report = 1; 405 406 list_for_each_entry(crs, &info->all_publ, all_publ) { 407 tipc_sub_report_overlap(sub, sseq->lower, 408 sseq->upper, 409 TIPC_PUBLISHED, 410 crs->port, 411 crs->node, 412 crs->scope, 413 must_report); 414 must_report = 0; 415 } 416 } 417 sseq++; 418 } 419 } 420 421 static struct name_seq *nametbl_find_seq(struct net *net, u32 type) 422 { 423 struct tipc_net *tn = net_generic(net, tipc_net_id); 424 struct hlist_head *seq_head; 425 struct name_seq *ns; 426 427 seq_head = &tn->nametbl->seq_hlist[hash(type)]; 428 hlist_for_each_entry_rcu(ns, seq_head, ns_list) { 429 if (ns->type == type) 430 return ns; 431 } 432 433 return NULL; 434 }; 435 436 struct publication *tipc_nametbl_insert_publ(struct net *net, u32 type, 437 u32 lower, u32 upper, u32 scope, 438 u32 node, u32 port, u32 key) 439 { 440 struct tipc_net *tn = net_generic(net, tipc_net_id); 441 struct publication *publ; 442 struct name_seq *seq = nametbl_find_seq(net, type); 443 int index = hash(type); 444 445 if (scope > TIPC_NODE_SCOPE || lower > upper) { 446 pr_debug("Failed to publish illegal {%u,%u,%u} with scope %u\n", 447 type, lower, upper, scope); 448 return NULL; 449 } 450 451 if (!seq) 452 seq = tipc_nameseq_create(type, &tn->nametbl->seq_hlist[index]); 453 if (!seq) 454 return NULL; 455 456 spin_lock_bh(&seq->lock); 457 publ = tipc_nameseq_insert_publ(net, seq, type, lower, upper, 458 scope, node, port, key); 459 spin_unlock_bh(&seq->lock); 460 return publ; 461 } 462 463 struct publication *tipc_nametbl_remove_publ(struct net *net, u32 type, 464 u32 lower, u32 node, u32 port, 465 u32 key) 466 { 467 struct publication *publ; 468 struct name_seq *seq = nametbl_find_seq(net, type); 469 470 if (!seq) 471 return NULL; 472 473 spin_lock_bh(&seq->lock); 474 publ = tipc_nameseq_remove_publ(net, seq, lower, node, port, key); 475 if (!seq->first_free && list_empty(&seq->subscriptions)) { 476 hlist_del_init_rcu(&seq->ns_list); 477 kfree(seq->sseqs); 478 spin_unlock_bh(&seq->lock); 479 kfree_rcu(seq, rcu); 480 return publ; 481 } 482 spin_unlock_bh(&seq->lock); 483 return publ; 484 } 485 486 /** 487 * tipc_nametbl_translate - perform name translation 488 * 489 * On entry, 'destnode' is the search domain used during translation. 490 * 491 * On exit: 492 * - if name translation is deferred to another node/cluster/zone, 493 * leaves 'destnode' unchanged (will be non-zero) and returns 0 494 * - if name translation is attempted and succeeds, sets 'destnode' 495 * to publishing node and returns port reference (will be non-zero) 496 * - if name translation is attempted and fails, sets 'destnode' to 0 497 * and returns 0 498 */ 499 u32 tipc_nametbl_translate(struct net *net, u32 type, u32 instance, 500 u32 *destnode) 501 { 502 struct tipc_net *tn = net_generic(net, tipc_net_id); 503 struct sub_seq *sseq; 504 struct name_info *info; 505 struct publication *publ; 506 struct name_seq *seq; 507 u32 port = 0; 508 u32 node = 0; 509 510 if (!tipc_in_scope(*destnode, tn->own_addr)) 511 return 0; 512 513 rcu_read_lock(); 514 seq = nametbl_find_seq(net, type); 515 if (unlikely(!seq)) 516 goto not_found; 517 spin_lock_bh(&seq->lock); 518 sseq = nameseq_find_subseq(seq, instance); 519 if (unlikely(!sseq)) 520 goto no_match; 521 info = sseq->info; 522 523 /* Closest-First Algorithm */ 524 if (likely(!*destnode)) { 525 if (!list_empty(&info->local_publ)) { 526 publ = list_first_entry(&info->local_publ, 527 struct publication, 528 local_publ); 529 list_move_tail(&publ->local_publ, 530 &info->local_publ); 531 } else { 532 publ = list_first_entry(&info->all_publ, 533 struct publication, 534 all_publ); 535 list_move_tail(&publ->all_publ, 536 &info->all_publ); 537 } 538 } 539 540 /* Round-Robin Algorithm */ 541 else if (*destnode == tn->own_addr) { 542 if (list_empty(&info->local_publ)) 543 goto no_match; 544 publ = list_first_entry(&info->local_publ, struct publication, 545 local_publ); 546 list_move_tail(&publ->local_publ, &info->local_publ); 547 } else { 548 publ = list_first_entry(&info->all_publ, struct publication, 549 all_publ); 550 list_move_tail(&publ->all_publ, &info->all_publ); 551 } 552 553 port = publ->port; 554 node = publ->node; 555 no_match: 556 spin_unlock_bh(&seq->lock); 557 not_found: 558 rcu_read_unlock(); 559 *destnode = node; 560 return port; 561 } 562 563 bool tipc_nametbl_lookup(struct net *net, u32 type, u32 instance, u32 scope, 564 struct list_head *dsts, int *dstcnt, u32 exclude, 565 bool all) 566 { 567 u32 self = tipc_own_addr(net); 568 struct publication *publ; 569 struct name_info *info; 570 struct name_seq *seq; 571 struct sub_seq *sseq; 572 573 *dstcnt = 0; 574 rcu_read_lock(); 575 seq = nametbl_find_seq(net, type); 576 if (unlikely(!seq)) 577 goto exit; 578 spin_lock_bh(&seq->lock); 579 sseq = nameseq_find_subseq(seq, instance); 580 if (likely(sseq)) { 581 info = sseq->info; 582 list_for_each_entry(publ, &info->all_publ, all_publ) { 583 if (publ->scope != scope) 584 continue; 585 if (publ->port == exclude && publ->node == self) 586 continue; 587 tipc_dest_push(dsts, publ->node, publ->port); 588 (*dstcnt)++; 589 if (all) 590 continue; 591 list_move_tail(&publ->all_publ, &info->all_publ); 592 break; 593 } 594 } 595 spin_unlock_bh(&seq->lock); 596 exit: 597 rcu_read_unlock(); 598 return !list_empty(dsts); 599 } 600 601 void tipc_nametbl_mc_lookup(struct net *net, u32 type, u32 lower, u32 upper, 602 u32 scope, bool exact, struct list_head *dports) 603 { 604 struct sub_seq *sseq_stop; 605 struct name_info *info; 606 struct publication *p; 607 struct name_seq *seq; 608 struct sub_seq *sseq; 609 610 rcu_read_lock(); 611 seq = nametbl_find_seq(net, type); 612 if (!seq) 613 goto exit; 614 615 spin_lock_bh(&seq->lock); 616 sseq = seq->sseqs + nameseq_locate_subseq(seq, lower); 617 sseq_stop = seq->sseqs + seq->first_free; 618 for (; sseq != sseq_stop; sseq++) { 619 if (sseq->lower > upper) 620 break; 621 info = sseq->info; 622 list_for_each_entry(p, &info->local_publ, local_publ) { 623 if (p->scope == scope || (!exact && p->scope < scope)) 624 tipc_dest_push(dports, 0, p->port); 625 } 626 } 627 spin_unlock_bh(&seq->lock); 628 exit: 629 rcu_read_unlock(); 630 } 631 632 /* tipc_nametbl_lookup_dst_nodes - find broadcast destination nodes 633 * - Creates list of nodes that overlap the given multicast address 634 * - Determines if any node local ports overlap 635 */ 636 void tipc_nametbl_lookup_dst_nodes(struct net *net, u32 type, u32 lower, 637 u32 upper, struct tipc_nlist *nodes) 638 { 639 struct sub_seq *sseq, *stop; 640 struct publication *publ; 641 struct name_info *info; 642 struct name_seq *seq; 643 644 rcu_read_lock(); 645 seq = nametbl_find_seq(net, type); 646 if (!seq) 647 goto exit; 648 649 spin_lock_bh(&seq->lock); 650 sseq = seq->sseqs + nameseq_locate_subseq(seq, lower); 651 stop = seq->sseqs + seq->first_free; 652 for (; sseq != stop && sseq->lower <= upper; sseq++) { 653 info = sseq->info; 654 list_for_each_entry(publ, &info->all_publ, all_publ) { 655 tipc_nlist_add(nodes, publ->node); 656 } 657 } 658 spin_unlock_bh(&seq->lock); 659 exit: 660 rcu_read_unlock(); 661 } 662 663 /* tipc_nametbl_build_group - build list of communication group members 664 */ 665 void tipc_nametbl_build_group(struct net *net, struct tipc_group *grp, 666 u32 type, u32 scope) 667 { 668 struct sub_seq *sseq, *stop; 669 struct name_info *info; 670 struct publication *p; 671 struct name_seq *seq; 672 673 rcu_read_lock(); 674 seq = nametbl_find_seq(net, type); 675 if (!seq) 676 goto exit; 677 678 spin_lock_bh(&seq->lock); 679 sseq = seq->sseqs; 680 stop = seq->sseqs + seq->first_free; 681 for (; sseq != stop; sseq++) { 682 info = sseq->info; 683 list_for_each_entry(p, &info->all_publ, all_publ) { 684 if (p->scope != scope) 685 continue; 686 tipc_group_add_member(grp, p->node, p->port, p->lower); 687 } 688 } 689 spin_unlock_bh(&seq->lock); 690 exit: 691 rcu_read_unlock(); 692 } 693 694 /* 695 * tipc_nametbl_publish - add name publication to network name tables 696 */ 697 struct publication *tipc_nametbl_publish(struct net *net, u32 type, u32 lower, 698 u32 upper, u32 scope, u32 port_ref, 699 u32 key) 700 { 701 struct publication *publ; 702 struct sk_buff *buf = NULL; 703 struct tipc_net *tn = net_generic(net, tipc_net_id); 704 705 spin_lock_bh(&tn->nametbl_lock); 706 if (tn->nametbl->local_publ_count >= TIPC_MAX_PUBLICATIONS) { 707 pr_warn("Publication failed, local publication limit reached (%u)\n", 708 TIPC_MAX_PUBLICATIONS); 709 spin_unlock_bh(&tn->nametbl_lock); 710 return NULL; 711 } 712 713 publ = tipc_nametbl_insert_publ(net, type, lower, upper, scope, 714 tn->own_addr, port_ref, key); 715 if (likely(publ)) { 716 tn->nametbl->local_publ_count++; 717 buf = tipc_named_publish(net, publ); 718 /* Any pending external events? */ 719 tipc_named_process_backlog(net); 720 } 721 spin_unlock_bh(&tn->nametbl_lock); 722 723 if (buf) 724 tipc_node_broadcast(net, buf); 725 return publ; 726 } 727 728 /** 729 * tipc_nametbl_withdraw - withdraw name publication from network name tables 730 */ 731 int tipc_nametbl_withdraw(struct net *net, u32 type, u32 lower, u32 port, 732 u32 key) 733 { 734 struct publication *publ; 735 struct sk_buff *skb = NULL; 736 struct tipc_net *tn = net_generic(net, tipc_net_id); 737 738 spin_lock_bh(&tn->nametbl_lock); 739 publ = tipc_nametbl_remove_publ(net, type, lower, tn->own_addr, 740 port, key); 741 if (likely(publ)) { 742 tn->nametbl->local_publ_count--; 743 skb = tipc_named_withdraw(net, publ); 744 /* Any pending external events? */ 745 tipc_named_process_backlog(net); 746 list_del_init(&publ->binding_sock); 747 kfree_rcu(publ, rcu); 748 } else { 749 pr_err("Unable to remove local publication\n" 750 "(type=%u, lower=%u, port=%u, key=%u)\n", 751 type, lower, port, key); 752 } 753 spin_unlock_bh(&tn->nametbl_lock); 754 755 if (skb) { 756 tipc_node_broadcast(net, skb); 757 return 1; 758 } 759 return 0; 760 } 761 762 /** 763 * tipc_nametbl_subscribe - add a subscription object to the name table 764 */ 765 void tipc_nametbl_subscribe(struct tipc_subscription *sub) 766 { 767 struct tipc_net *tn = tipc_net(sub->net); 768 struct tipc_subscr *s = &sub->evt.s; 769 u32 type = tipc_sub_read(s, seq.type); 770 int index = hash(type); 771 struct name_seq *seq; 772 struct tipc_name_seq ns; 773 774 spin_lock_bh(&tn->nametbl_lock); 775 seq = nametbl_find_seq(sub->net, type); 776 if (!seq) 777 seq = tipc_nameseq_create(type, &tn->nametbl->seq_hlist[index]); 778 if (seq) { 779 spin_lock_bh(&seq->lock); 780 tipc_nameseq_subscribe(seq, sub); 781 spin_unlock_bh(&seq->lock); 782 } else { 783 ns.type = tipc_sub_read(s, seq.type); 784 ns.lower = tipc_sub_read(s, seq.lower); 785 ns.upper = tipc_sub_read(s, seq.upper); 786 pr_warn("Failed to create subscription for {%u,%u,%u}\n", 787 ns.type, ns.lower, ns.upper); 788 } 789 spin_unlock_bh(&tn->nametbl_lock); 790 } 791 792 /** 793 * tipc_nametbl_unsubscribe - remove a subscription object from name table 794 */ 795 void tipc_nametbl_unsubscribe(struct tipc_subscription *sub) 796 { 797 struct tipc_subscr *s = &sub->evt.s; 798 struct tipc_net *tn = tipc_net(sub->net); 799 struct name_seq *seq; 800 u32 type = tipc_sub_read(s, seq.type); 801 802 spin_lock_bh(&tn->nametbl_lock); 803 seq = nametbl_find_seq(sub->net, type); 804 if (seq != NULL) { 805 spin_lock_bh(&seq->lock); 806 list_del_init(&sub->nameseq_list); 807 tipc_sub_put(sub); 808 if (!seq->first_free && list_empty(&seq->subscriptions)) { 809 hlist_del_init_rcu(&seq->ns_list); 810 kfree(seq->sseqs); 811 spin_unlock_bh(&seq->lock); 812 kfree_rcu(seq, rcu); 813 } else { 814 spin_unlock_bh(&seq->lock); 815 } 816 } 817 spin_unlock_bh(&tn->nametbl_lock); 818 } 819 820 int tipc_nametbl_init(struct net *net) 821 { 822 struct tipc_net *tn = net_generic(net, tipc_net_id); 823 struct name_table *tipc_nametbl; 824 int i; 825 826 tipc_nametbl = kzalloc(sizeof(*tipc_nametbl), GFP_ATOMIC); 827 if (!tipc_nametbl) 828 return -ENOMEM; 829 830 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) 831 INIT_HLIST_HEAD(&tipc_nametbl->seq_hlist[i]); 832 833 INIT_LIST_HEAD(&tipc_nametbl->node_scope); 834 INIT_LIST_HEAD(&tipc_nametbl->cluster_scope); 835 tn->nametbl = tipc_nametbl; 836 spin_lock_init(&tn->nametbl_lock); 837 return 0; 838 } 839 840 /** 841 * tipc_purge_publications - remove all publications for a given type 842 * 843 * tipc_nametbl_lock must be held when calling this function 844 */ 845 static void tipc_purge_publications(struct net *net, struct name_seq *seq) 846 { 847 struct publication *publ, *safe; 848 struct sub_seq *sseq; 849 struct name_info *info; 850 851 spin_lock_bh(&seq->lock); 852 sseq = seq->sseqs; 853 info = sseq->info; 854 list_for_each_entry_safe(publ, safe, &info->all_publ, all_publ) { 855 tipc_nameseq_remove_publ(net, seq, publ->lower, publ->node, 856 publ->port, publ->key); 857 kfree_rcu(publ, rcu); 858 } 859 hlist_del_init_rcu(&seq->ns_list); 860 kfree(seq->sseqs); 861 spin_unlock_bh(&seq->lock); 862 863 kfree_rcu(seq, rcu); 864 } 865 866 void tipc_nametbl_stop(struct net *net) 867 { 868 u32 i; 869 struct name_seq *seq; 870 struct hlist_head *seq_head; 871 struct tipc_net *tn = net_generic(net, tipc_net_id); 872 struct name_table *tipc_nametbl = tn->nametbl; 873 874 /* Verify name table is empty and purge any lingering 875 * publications, then release the name table 876 */ 877 spin_lock_bh(&tn->nametbl_lock); 878 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) { 879 if (hlist_empty(&tipc_nametbl->seq_hlist[i])) 880 continue; 881 seq_head = &tipc_nametbl->seq_hlist[i]; 882 hlist_for_each_entry_rcu(seq, seq_head, ns_list) { 883 tipc_purge_publications(net, seq); 884 } 885 } 886 spin_unlock_bh(&tn->nametbl_lock); 887 888 synchronize_net(); 889 kfree(tipc_nametbl); 890 891 } 892 893 static int __tipc_nl_add_nametable_publ(struct tipc_nl_msg *msg, 894 struct name_seq *seq, 895 struct sub_seq *sseq, u32 *last_publ) 896 { 897 void *hdr; 898 struct nlattr *attrs; 899 struct nlattr *publ; 900 struct publication *p; 901 902 if (*last_publ) { 903 list_for_each_entry(p, &sseq->info->all_publ, all_publ) 904 if (p->key == *last_publ) 905 break; 906 if (p->key != *last_publ) 907 return -EPIPE; 908 } else { 909 p = list_first_entry(&sseq->info->all_publ, struct publication, 910 all_publ); 911 } 912 913 list_for_each_entry_from(p, &sseq->info->all_publ, all_publ) { 914 *last_publ = p->key; 915 916 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, 917 &tipc_genl_family, NLM_F_MULTI, 918 TIPC_NL_NAME_TABLE_GET); 919 if (!hdr) 920 return -EMSGSIZE; 921 922 attrs = nla_nest_start(msg->skb, TIPC_NLA_NAME_TABLE); 923 if (!attrs) 924 goto msg_full; 925 926 publ = nla_nest_start(msg->skb, TIPC_NLA_NAME_TABLE_PUBL); 927 if (!publ) 928 goto attr_msg_full; 929 930 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_TYPE, seq->type)) 931 goto publ_msg_full; 932 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_LOWER, sseq->lower)) 933 goto publ_msg_full; 934 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_UPPER, sseq->upper)) 935 goto publ_msg_full; 936 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_SCOPE, p->scope)) 937 goto publ_msg_full; 938 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_NODE, p->node)) 939 goto publ_msg_full; 940 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_REF, p->port)) 941 goto publ_msg_full; 942 if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_KEY, p->key)) 943 goto publ_msg_full; 944 945 nla_nest_end(msg->skb, publ); 946 nla_nest_end(msg->skb, attrs); 947 genlmsg_end(msg->skb, hdr); 948 } 949 *last_publ = 0; 950 951 return 0; 952 953 publ_msg_full: 954 nla_nest_cancel(msg->skb, publ); 955 attr_msg_full: 956 nla_nest_cancel(msg->skb, attrs); 957 msg_full: 958 genlmsg_cancel(msg->skb, hdr); 959 960 return -EMSGSIZE; 961 } 962 963 static int __tipc_nl_subseq_list(struct tipc_nl_msg *msg, struct name_seq *seq, 964 u32 *last_lower, u32 *last_publ) 965 { 966 struct sub_seq *sseq; 967 struct sub_seq *sseq_start; 968 int err; 969 970 if (*last_lower) { 971 sseq_start = nameseq_find_subseq(seq, *last_lower); 972 if (!sseq_start) 973 return -EPIPE; 974 } else { 975 sseq_start = seq->sseqs; 976 } 977 978 for (sseq = sseq_start; sseq != &seq->sseqs[seq->first_free]; sseq++) { 979 err = __tipc_nl_add_nametable_publ(msg, seq, sseq, last_publ); 980 if (err) { 981 *last_lower = sseq->lower; 982 return err; 983 } 984 } 985 *last_lower = 0; 986 987 return 0; 988 } 989 990 static int tipc_nl_seq_list(struct net *net, struct tipc_nl_msg *msg, 991 u32 *last_type, u32 *last_lower, u32 *last_publ) 992 { 993 struct tipc_net *tn = net_generic(net, tipc_net_id); 994 struct hlist_head *seq_head; 995 struct name_seq *seq = NULL; 996 int err; 997 int i; 998 999 if (*last_type) 1000 i = hash(*last_type); 1001 else 1002 i = 0; 1003 1004 for (; i < TIPC_NAMETBL_SIZE; i++) { 1005 seq_head = &tn->nametbl->seq_hlist[i]; 1006 1007 if (*last_type) { 1008 seq = nametbl_find_seq(net, *last_type); 1009 if (!seq) 1010 return -EPIPE; 1011 } else { 1012 hlist_for_each_entry_rcu(seq, seq_head, ns_list) 1013 break; 1014 if (!seq) 1015 continue; 1016 } 1017 1018 hlist_for_each_entry_from_rcu(seq, ns_list) { 1019 spin_lock_bh(&seq->lock); 1020 err = __tipc_nl_subseq_list(msg, seq, last_lower, 1021 last_publ); 1022 1023 if (err) { 1024 *last_type = seq->type; 1025 spin_unlock_bh(&seq->lock); 1026 return err; 1027 } 1028 spin_unlock_bh(&seq->lock); 1029 } 1030 *last_type = 0; 1031 } 1032 return 0; 1033 } 1034 1035 int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb) 1036 { 1037 int err; 1038 int done = cb->args[3]; 1039 u32 last_type = cb->args[0]; 1040 u32 last_lower = cb->args[1]; 1041 u32 last_publ = cb->args[2]; 1042 struct net *net = sock_net(skb->sk); 1043 struct tipc_nl_msg msg; 1044 1045 if (done) 1046 return 0; 1047 1048 msg.skb = skb; 1049 msg.portid = NETLINK_CB(cb->skb).portid; 1050 msg.seq = cb->nlh->nlmsg_seq; 1051 1052 rcu_read_lock(); 1053 err = tipc_nl_seq_list(net, &msg, &last_type, &last_lower, &last_publ); 1054 if (!err) { 1055 done = 1; 1056 } else if (err != -EMSGSIZE) { 1057 /* We never set seq or call nl_dump_check_consistent() this 1058 * means that setting prev_seq here will cause the consistence 1059 * check to fail in the netlink callback handler. Resulting in 1060 * the NLMSG_DONE message having the NLM_F_DUMP_INTR flag set if 1061 * we got an error. 1062 */ 1063 cb->prev_seq = 1; 1064 } 1065 rcu_read_unlock(); 1066 1067 cb->args[0] = last_type; 1068 cb->args[1] = last_lower; 1069 cb->args[2] = last_publ; 1070 cb->args[3] = done; 1071 1072 return skb->len; 1073 } 1074 1075 struct tipc_dest *tipc_dest_find(struct list_head *l, u32 node, u32 port) 1076 { 1077 u64 value = (u64)node << 32 | port; 1078 struct tipc_dest *dst; 1079 1080 list_for_each_entry(dst, l, list) { 1081 if (dst->value != value) 1082 continue; 1083 return dst; 1084 } 1085 return NULL; 1086 } 1087 1088 bool tipc_dest_push(struct list_head *l, u32 node, u32 port) 1089 { 1090 u64 value = (u64)node << 32 | port; 1091 struct tipc_dest *dst; 1092 1093 if (tipc_dest_find(l, node, port)) 1094 return false; 1095 1096 dst = kmalloc(sizeof(*dst), GFP_ATOMIC); 1097 if (unlikely(!dst)) 1098 return false; 1099 dst->value = value; 1100 list_add(&dst->list, l); 1101 return true; 1102 } 1103 1104 bool tipc_dest_pop(struct list_head *l, u32 *node, u32 *port) 1105 { 1106 struct tipc_dest *dst; 1107 1108 if (list_empty(l)) 1109 return false; 1110 dst = list_first_entry(l, typeof(*dst), list); 1111 if (port) 1112 *port = dst->port; 1113 if (node) 1114 *node = dst->node; 1115 list_del(&dst->list); 1116 kfree(dst); 1117 return true; 1118 } 1119 1120 bool tipc_dest_del(struct list_head *l, u32 node, u32 port) 1121 { 1122 struct tipc_dest *dst; 1123 1124 dst = tipc_dest_find(l, node, port); 1125 if (!dst) 1126 return false; 1127 list_del(&dst->list); 1128 kfree(dst); 1129 return true; 1130 } 1131 1132 void tipc_dest_list_purge(struct list_head *l) 1133 { 1134 struct tipc_dest *dst, *tmp; 1135 1136 list_for_each_entry_safe(dst, tmp, l, list) { 1137 list_del(&dst->list); 1138 kfree(dst); 1139 } 1140 } 1141 1142 int tipc_dest_list_len(struct list_head *l) 1143 { 1144 struct tipc_dest *dst; 1145 int i = 0; 1146 1147 list_for_each_entry(dst, l, list) { 1148 i++; 1149 } 1150 return i; 1151 } 1152