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 * Copyright (c) 2020-2021, Red Hat Inc
   7 * All rights reserved.
   8 *
   9 * Redistribution and use in source and binary forms, with or without
  10 * modification, are permitted provided that the following conditions are met:
  11 *
  12 * 1. Redistributions of source code must retain the above copyright
  13 *    notice, this list of conditions and the following disclaimer.
  14 * 2. Redistributions in binary form must reproduce the above copyright
  15 *    notice, this list of conditions and the following disclaimer in the
  16 *    documentation and/or other materials provided with the distribution.
  17 * 3. Neither the names of the copyright holders nor the names of its
  18 *    contributors may be used to endorse or promote products derived from
  19 *    this software without specific prior written permission.
  20 *
  21 * Alternatively, this software may be distributed under the terms of the
  22 * GNU General Public License ("GPL") version 2 as published by the Free
  23 * Software Foundation.
  24 *
  25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  26 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  28 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  29 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  35 * POSSIBILITY OF SUCH DAMAGE.
  36 */
  37
  38#include <net/sock.h>
  39#include <linux/list_sort.h>
  40#include <linux/rbtree_augmented.h>
  41#include "core.h"
  42#include "netlink.h"
  43#include "name_table.h"
  44#include "name_distr.h"
  45#include "subscr.h"
  46#include "bcast.h"
  47#include "addr.h"
  48#include "node.h"
  49#include "group.h"
  50
  51/**
  52 * struct service_range - container for all bindings of a service range
  53 * @lower: service range lower bound
  54 * @upper: service range upper bound
  55 * @tree_node: member of service range RB tree
  56 * @max: largest 'upper' in this node subtree
  57 * @local_publ: list of identical publications made from this node
  58 *   Used by closest_first lookup and multicast lookup algorithm
  59 * @all_publ: all publications identical to this one, whatever node and scope
  60 *   Used by round-robin lookup algorithm
  61 */
  62struct service_range {
  63	u32 lower;
  64	u32 upper;
  65	struct rb_node tree_node;
  66	u32 max;
  67	struct list_head local_publ;
  68	struct list_head all_publ;
  69};
  70
  71/**
  72 * struct tipc_service - container for all published instances of a service type
  73 * @type: 32 bit 'type' value for service
  74 * @publ_cnt: increasing counter for publications in this service
  75 * @ranges: rb tree containing all service ranges for this service
  76 * @service_list: links to adjacent name ranges in hash chain
  77 * @subscriptions: list of subscriptions for this service type
  78 * @lock: spinlock controlling access to pertaining service ranges/publications
  79 * @rcu: RCU callback head used for deferred freeing
  80 */
  81struct tipc_service {
  82	u32 type;
  83	u32 publ_cnt;
  84	struct rb_root ranges;
  85	struct hlist_node service_list;
  86	struct list_head subscriptions;
  87	spinlock_t lock; /* Covers service range list */
  88	struct rcu_head rcu;
  89};
  90
  91#define service_range_upper(sr) ((sr)->upper)
  92RB_DECLARE_CALLBACKS_MAX(static, sr_callbacks,
  93			 struct service_range, tree_node, u32, max,
  94			 service_range_upper)
  95
  96#define service_range_entry(rbtree_node)				\
  97	(container_of(rbtree_node, struct service_range, tree_node))
  98
  99#define service_range_overlap(sr, start, end)				\
 100	((sr)->lower <= (end) && (sr)->upper >= (start))
 101
 102/**
 103 * service_range_foreach_match - iterate over tipc service rbtree for each
 104 *                               range match
 105 * @sr: the service range pointer as a loop cursor
 106 * @sc: the pointer to tipc service which holds the service range rbtree
 107 * @start: beginning of the search range (end >= start) for matching
 108 * @end: end of the search range (end >= start) for matching
 109 */
 110#define service_range_foreach_match(sr, sc, start, end)			\
 111	for (sr = service_range_match_first((sc)->ranges.rb_node,	\
 112					    start,			\
 113					    end);			\
 114	     sr;							\
 115	     sr = service_range_match_next(&(sr)->tree_node,		\
 116					   start,			\
 117					   end))
 118
 119/**
 120 * service_range_match_first - find first service range matching a range
 121 * @n: the root node of service range rbtree for searching
 122 * @start: beginning of the search range (end >= start) for matching
 123 * @end: end of the search range (end >= start) for matching
 124 *
 125 * Return: the leftmost service range node in the rbtree that overlaps the
 126 * specific range if any. Otherwise, returns NULL.
 127 */
 128static struct service_range *service_range_match_first(struct rb_node *n,
 129						       u32 start, u32 end)
 130{
 131	struct service_range *sr;
 132	struct rb_node *l, *r;
 133
 134	/* Non overlaps in tree at all? */
 135	if (!n || service_range_entry(n)->max < start)
 136		return NULL;
 137
 138	while (n) {
 139		l = n->rb_left;
 140		if (l && service_range_entry(l)->max >= start) {
 141			/* A leftmost overlap range node must be one in the left
 142			 * subtree. If not, it has lower > end, then nodes on
 143			 * the right side cannot satisfy the condition either.
 144			 */
 145			n = l;
 146			continue;
 147		}
 148
 149		/* No one in the left subtree can match, return if this node is
 150		 * an overlap i.e. leftmost.
 151		 */
 152		sr = service_range_entry(n);
 153		if (service_range_overlap(sr, start, end))
 154			return sr;
 155
 156		/* Ok, try to lookup on the right side */
 157		r = n->rb_right;
 158		if (sr->lower <= end &&
 159		    r && service_range_entry(r)->max >= start) {
 160			n = r;
 161			continue;
 162		}
 163		break;
 164	}
 165
 166	return NULL;
 167}
 168
 169/**
 170 * service_range_match_next - find next service range matching a range
 171 * @n: a node in service range rbtree from which the searching starts
 172 * @start: beginning of the search range (end >= start) for matching
 173 * @end: end of the search range (end >= start) for matching
 174 *
 175 * Return: the next service range node to the given node in the rbtree that
 176 * overlaps the specific range if any. Otherwise, returns NULL.
 177 */
 178static struct service_range *service_range_match_next(struct rb_node *n,
 179						      u32 start, u32 end)
 180{
 181	struct service_range *sr;
 182	struct rb_node *p, *r;
 183
 184	while (n) {
 185		r = n->rb_right;
 186		if (r && service_range_entry(r)->max >= start)
 187			/* A next overlap range node must be one in the right
 188			 * subtree. If not, it has lower > end, then any next
 189			 * successor (- an ancestor) of this node cannot
 190			 * satisfy the condition either.
 191			 */
 192			return service_range_match_first(r, start, end);
 193
 194		/* No one in the right subtree can match, go up to find an
 195		 * ancestor of this node which is parent of a left-hand child.
 196		 */
 197		while ((p = rb_parent(n)) && n == p->rb_right)
 198			n = p;
 199		if (!p)
 200			break;
 201
 202		/* Return if this ancestor is an overlap */
 203		sr = service_range_entry(p);
 204		if (service_range_overlap(sr, start, end))
 205			return sr;
 206
 207		/* Ok, try to lookup more from this ancestor */
 208		if (sr->lower <= end) {
 209			n = p;
 210			continue;
 211		}
 212		break;
 213	}
 214
 215	return NULL;
 216}
 217
 218static int hash(int x)
 219{
 220	return x & (TIPC_NAMETBL_SIZE - 1);
 221}
 222
 223/**
 224 * tipc_publ_create - create a publication structure
 225 * @ua: the service range the user is binding to
 226 * @sk: the address of the socket that is bound
 227 * @key: publication key
 228 */
 229static struct publication *tipc_publ_create(struct tipc_uaddr *ua,
 230					    struct tipc_socket_addr *sk,
 231					    u32 key)
 232{
 233	struct publication *p = kzalloc(sizeof(*p), GFP_ATOMIC);
 234
 235	if (!p)
 236		return NULL;
 237
 238	p->sr = ua->sr;
 239	p->sk = *sk;
 240	p->scope = ua->scope;
 241	p->key = key;
 242	INIT_LIST_HEAD(&p->binding_sock);
 243	INIT_LIST_HEAD(&p->binding_node);
 244	INIT_LIST_HEAD(&p->local_publ);
 245	INIT_LIST_HEAD(&p->all_publ);
 246	INIT_LIST_HEAD(&p->list);
 247	return p;
 248}
 249
 250/**
 251 * tipc_service_create - create a service structure for the specified 'type'
 252 * @net: network namespace
 253 * @ua: address representing the service to be bound
 254 *
 255 * Allocates a single range structure and sets it to all 0's.
 256 */
 257static struct tipc_service *tipc_service_create(struct net *net,
 258						struct tipc_uaddr *ua)
 259{
 260	struct name_table *nt = tipc_name_table(net);
 261	struct tipc_service *service;
 262	struct hlist_head *hd;
 263
 264	service = kzalloc(sizeof(*service), GFP_ATOMIC);
 265	if (!service) {
 266		pr_warn("Service creation failed, no memory\n");
 267		return NULL;
 268	}
 269
 270	spin_lock_init(&service->lock);
 271	service->type = ua->sr.type;
 272	service->ranges = RB_ROOT;
 273	INIT_HLIST_NODE(&service->service_list);
 274	INIT_LIST_HEAD(&service->subscriptions);
 275	hd = &nt->services[hash(ua->sr.type)];
 276	hlist_add_head_rcu(&service->service_list, hd);
 277	return service;
 278}
 279
 280/*  tipc_service_find_range - find service range matching publication parameters
 281 */
 282static struct service_range *tipc_service_find_range(struct tipc_service *sc,
 283						     struct tipc_uaddr *ua)
 284{
 285	struct service_range *sr;
 286
 287	service_range_foreach_match(sr, sc, ua->sr.lower, ua->sr.upper) {
 288		/* Look for exact match */
 289		if (sr->lower == ua->sr.lower && sr->upper == ua->sr.upper)
 290			return sr;
 291	}
 292
 293	return NULL;
 294}
 295
 296static struct service_range *tipc_service_create_range(struct tipc_service *sc,
 297						       struct publication *p)
 298{
 299	struct rb_node **n, *parent = NULL;
 300	struct service_range *sr;
 301	u32 lower = p->sr.lower;
 302	u32 upper = p->sr.upper;
 303
 304	n = &sc->ranges.rb_node;
 305	while (*n) {
 306		parent = *n;
 307		sr = service_range_entry(parent);
 308		if (lower == sr->lower && upper == sr->upper)
 309			return sr;
 310		if (sr->max < upper)
 311			sr->max = upper;
 312		if (lower <= sr->lower)
 313			n = &parent->rb_left;
 314		else
 315			n = &parent->rb_right;
 316	}
 317	sr = kzalloc(sizeof(*sr), GFP_ATOMIC);
 318	if (!sr)
 319		return NULL;
 320	sr->lower = lower;
 321	sr->upper = upper;
 322	sr->max = upper;
 323	INIT_LIST_HEAD(&sr->local_publ);
 324	INIT_LIST_HEAD(&sr->all_publ);
 325	rb_link_node(&sr->tree_node, parent, n);
 326	rb_insert_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks);
 327	return sr;
 328}
 329
 330static bool tipc_service_insert_publ(struct net *net,
 331				     struct tipc_service *sc,
 332				     struct publication *p)
 333{
 334	struct tipc_subscription *sub, *tmp;
 335	struct service_range *sr;
 336	struct publication *_p;
 337	u32 node = p->sk.node;
 338	bool first = false;
 339	bool res = false;
 340	u32 key = p->key;
 341
 342	spin_lock_bh(&sc->lock);
 343	sr = tipc_service_create_range(sc, p);
 344	if (!sr)
 345		goto  exit;
 346
 347	first = list_empty(&sr->all_publ);
 348
 349	/* Return if the publication already exists */
 350	list_for_each_entry(_p, &sr->all_publ, all_publ) {
 351		if (_p->key == key && (!_p->sk.node || _p->sk.node == node)) {
 352			pr_debug("Failed to bind duplicate %u,%u,%u/%u:%u/%u\n",
 353				 p->sr.type, p->sr.lower, p->sr.upper,
 354				 node, p->sk.ref, key);
 355			goto exit;
 356		}
 357	}
 358
 359	if (in_own_node(net, p->sk.node))
 360		list_add(&p->local_publ, &sr->local_publ);
 361	list_add(&p->all_publ, &sr->all_publ);
 362	p->id = sc->publ_cnt++;
 363
 364	/* Any subscriptions waiting for notification?  */
 365	list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) {
 366		tipc_sub_report_overlap(sub, p, TIPC_PUBLISHED, first);
 367	}
 368	res = true;
 369exit:
 370	if (!res)
 371		pr_warn("Failed to bind to %u,%u,%u\n",
 372			p->sr.type, p->sr.lower, p->sr.upper);
 373	spin_unlock_bh(&sc->lock);
 374	return res;
 375}
 376
 377/**
 378 * tipc_service_remove_publ - remove a publication from a service
 379 * @r: service_range to remove publication from
 380 * @sk: address publishing socket
 381 * @key: target publication key
 382 */
 383static struct publication *tipc_service_remove_publ(struct service_range *r,
 384						    struct tipc_socket_addr *sk,
 385						    u32 key)
 386{
 387	struct publication *p;
 388	u32 node = sk->node;
 389
 390	list_for_each_entry(p, &r->all_publ, all_publ) {
 391		if (p->key != key || (node && node != p->sk.node))
 392			continue;
 393		list_del(&p->all_publ);
 394		list_del(&p->local_publ);
 395		return p;
 396	}
 397	return NULL;
 398}
 399
 400/*
 401 * Code reused: time_after32() for the same purpose
 402 */
 403#define publication_after(pa, pb) time_after32((pa)->id, (pb)->id)
 404static int tipc_publ_sort(void *priv, const struct list_head *a,
 405			  const struct list_head *b)
 406{
 407	struct publication *pa, *pb;
 408
 409	pa = container_of(a, struct publication, list);
 410	pb = container_of(b, struct publication, list);
 411	return publication_after(pa, pb);
 412}
 413
 414/**
 415 * tipc_service_subscribe - attach a subscription, and optionally
 416 * issue the prescribed number of events if there is any service
 417 * range overlapping with the requested range
 418 * @service: the tipc_service to attach the @sub to
 419 * @sub: the subscription to attach
 420 */
 421static void tipc_service_subscribe(struct tipc_service *service,
 422				   struct tipc_subscription *sub)
 423{
 424	struct publication *p, *first, *tmp;
 425	struct list_head publ_list;
 426	struct service_range *sr;
 427	u32 filter, lower, upper;
 428
 429	filter = sub->s.filter;
 430	lower = sub->s.seq.lower;
 431	upper = sub->s.seq.upper;
 432
 433	tipc_sub_get(sub);
 434	list_add(&sub->service_list, &service->subscriptions);
 435
 436	if (filter & TIPC_SUB_NO_STATUS)
 437		return;
 438
 439	INIT_LIST_HEAD(&publ_list);
 440	service_range_foreach_match(sr, service, lower, upper) {
 441		first = NULL;
 442		list_for_each_entry(p, &sr->all_publ, all_publ) {
 443			if (filter & TIPC_SUB_PORTS)
 444				list_add_tail(&p->list, &publ_list);
 445			else if (!first || publication_after(first, p))
 446				/* Pick this range's *first* publication */
 447				first = p;
 448		}
 449		if (first)
 450			list_add_tail(&first->list, &publ_list);
 451	}
 452
 453	/* Sort the publications before reporting */
 454	list_sort(NULL, &publ_list, tipc_publ_sort);
 455	list_for_each_entry_safe(p, tmp, &publ_list, list) {
 456		tipc_sub_report_overlap(sub, p, TIPC_PUBLISHED, true);
 457		list_del_init(&p->list);
 458	}
 459}
 460
 461static struct tipc_service *tipc_service_find(struct net *net,
 462					      struct tipc_uaddr *ua)
 463{
 464	struct name_table *nt = tipc_name_table(net);
 465	struct hlist_head *service_head;
 466	struct tipc_service *service;
 467
 468	service_head = &nt->services[hash(ua->sr.type)];
 469	hlist_for_each_entry_rcu(service, service_head, service_list) {
 470		if (service->type == ua->sr.type)
 471			return service;
 472	}
 473	return NULL;
 474};
 475
 476struct publication *tipc_nametbl_insert_publ(struct net *net,
 477					     struct tipc_uaddr *ua,
 478					     struct tipc_socket_addr *sk,
 479					     u32 key)
 480{
 481	struct tipc_service *sc;
 482	struct publication *p;
 483
 484	p = tipc_publ_create(ua, sk, key);
 485	if (!p)
 486		return NULL;
 487
 488	sc = tipc_service_find(net, ua);
 489	if (!sc)
 490		sc = tipc_service_create(net, ua);
 491	if (sc && tipc_service_insert_publ(net, sc, p))
 492		return p;
 493	kfree(p);
 494	return NULL;
 495}
 496
 497struct publication *tipc_nametbl_remove_publ(struct net *net,
 498					     struct tipc_uaddr *ua,
 499					     struct tipc_socket_addr *sk,
 500					     u32 key)
 501{
 502	struct tipc_subscription *sub, *tmp;
 503	struct publication *p = NULL;
 504	struct service_range *sr;
 505	struct tipc_service *sc;
 506	bool last;
 507
 508	sc = tipc_service_find(net, ua);
 509	if (!sc)
 510		goto exit;
 511
 512	spin_lock_bh(&sc->lock);
 513	sr = tipc_service_find_range(sc, ua);
 514	if (!sr)
 515		goto unlock;
 516	p = tipc_service_remove_publ(sr, sk, key);
 517	if (!p)
 518		goto unlock;
 519
 520	/* Notify any waiting subscriptions */
 521	last = list_empty(&sr->all_publ);
 522	list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) {
 523		tipc_sub_report_overlap(sub, p, TIPC_WITHDRAWN, last);
 524	}
 525
 526	/* Remove service range item if this was its last publication */
 527	if (list_empty(&sr->all_publ)) {
 528		rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks);
 529		kfree(sr);
 530	}
 531
 532	/* Delete service item if no more publications and subscriptions */
 533	if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) {
 534		hlist_del_init_rcu(&sc->service_list);
 535		kfree_rcu(sc, rcu);
 536	}
 537unlock:
 538	spin_unlock_bh(&sc->lock);
 539exit:
 540	if (!p) {
 541		pr_err("Failed to remove unknown binding: %u,%u,%u/%u:%u/%u\n",
 542		       ua->sr.type, ua->sr.lower, ua->sr.upper,
 543		       sk->node, sk->ref, key);
 544	}
 545	return p;
 546}
 547
 548/**
 549 * tipc_nametbl_lookup_anycast - perform service instance to socket translation
 550 * @net: network namespace
 551 * @ua: service address to look up
 552 * @sk: address to socket we want to find
 553 *
 554 * On entry, a non-zero 'sk->node' indicates the node where we want lookup to be
 555 * performed, which may not be this one.
 556 *
 557 * On exit:
 558 *
 559 * - If lookup is deferred to another node, leave 'sk->node' unchanged and
 560 *   return 'true'.
 561 * - If lookup is successful, set the 'sk->node' and 'sk->ref' (== portid) which
 562 *   represent the bound socket and return 'true'.
 563 * - If lookup fails, return 'false'
 564 *
 565 * Note that for legacy users (node configured with Z.C.N address format) the
 566 * 'closest-first' lookup algorithm must be maintained, i.e., if sk.node is 0
 567 * we must look in the local binding list first
 568 */
 569bool tipc_nametbl_lookup_anycast(struct net *net,
 570				 struct tipc_uaddr *ua,
 571				 struct tipc_socket_addr *sk)
 572{
 573	struct tipc_net *tn = tipc_net(net);
 574	bool legacy = tn->legacy_addr_format;
 575	u32 self = tipc_own_addr(net);
 576	u32 inst = ua->sa.instance;
 577	struct service_range *r;
 578	struct tipc_service *sc;
 579	struct publication *p;
 580	struct list_head *l;
 581	bool res = false;
 582
 583	if (!tipc_in_scope(legacy, sk->node, self))
 584		return true;
 585
 586	rcu_read_lock();
 587	sc = tipc_service_find(net, ua);
 588	if (unlikely(!sc))
 589		goto exit;
 590
 591	spin_lock_bh(&sc->lock);
 592	service_range_foreach_match(r, sc, inst, inst) {
 593		/* Select lookup algo: local, closest-first or round-robin */
 594		if (sk->node == self) {
 595			l = &r->local_publ;
 596			if (list_empty(l))
 597				continue;
 598			p = list_first_entry(l, struct publication, local_publ);
 599			list_move_tail(&p->local_publ, &r->local_publ);
 600		} else if (legacy && !sk->node && !list_empty(&r->local_publ)) {
 601			l = &r->local_publ;
 602			p = list_first_entry(l, struct publication, local_publ);
 603			list_move_tail(&p->local_publ, &r->local_publ);
 604		} else {
 605			l = &r->all_publ;
 606			p = list_first_entry(l, struct publication, all_publ);
 607			list_move_tail(&p->all_publ, &r->all_publ);
 608		}
 609		*sk = p->sk;
 610		res = true;
 611		/* Todo: as for legacy, pick the first matching range only, a
 612		 * "true" round-robin will be performed as needed.
 613		 */
 614		break;
 615	}
 616	spin_unlock_bh(&sc->lock);
 617
 618exit:
 619	rcu_read_unlock();
 620	return res;
 621}
 622
 623/* tipc_nametbl_lookup_group(): lookup destinaton(s) in a communication group
 624 * Returns a list of one (== group anycast) or more (== group multicast)
 625 * destination socket/node pairs matching the given address.
 626 * The requester may or may not want to exclude himself from the list.
 627 */
 628bool tipc_nametbl_lookup_group(struct net *net, struct tipc_uaddr *ua,
 629			       struct list_head *dsts, int *dstcnt,
 630			       u32 exclude, bool mcast)
 631{
 632	u32 self = tipc_own_addr(net);
 633	u32 inst = ua->sa.instance;
 634	struct service_range *sr;
 635	struct tipc_service *sc;
 636	struct publication *p;
 637
 638	*dstcnt = 0;
 639	rcu_read_lock();
 640	sc = tipc_service_find(net, ua);
 641	if (unlikely(!sc))
 642		goto exit;
 643
 644	spin_lock_bh(&sc->lock);
 645
 646	/* Todo: a full search i.e. service_range_foreach_match() instead? */
 647	sr = service_range_match_first(sc->ranges.rb_node, inst, inst);
 648	if (!sr)
 649		goto no_match;
 650
 651	list_for_each_entry(p, &sr->all_publ, all_publ) {
 652		if (p->scope != ua->scope)
 653			continue;
 654		if (p->sk.ref == exclude && p->sk.node == self)
 655			continue;
 656		tipc_dest_push(dsts, p->sk.node, p->sk.ref);
 657		(*dstcnt)++;
 658		if (mcast)
 659			continue;
 660		list_move_tail(&p->all_publ, &sr->all_publ);
 661		break;
 662	}
 663no_match:
 664	spin_unlock_bh(&sc->lock);
 665exit:
 666	rcu_read_unlock();
 667	return !list_empty(dsts);
 668}
 669
 670/* tipc_nametbl_lookup_mcast_sockets(): look up node local destinaton sockets
 671 *                                      matching the given address
 672 * Used on nodes which have received a multicast/broadcast message
 673 * Returns a list of local sockets
 674 */
 675void tipc_nametbl_lookup_mcast_sockets(struct net *net, struct tipc_uaddr *ua,
 676				       struct list_head *dports)
 677{
 678	struct service_range *sr;
 679	struct tipc_service *sc;
 680	struct publication *p;
 681	u8 scope = ua->scope;
 682
 683	rcu_read_lock();
 684	sc = tipc_service_find(net, ua);
 685	if (!sc)
 686		goto exit;
 687
 688	spin_lock_bh(&sc->lock);
 689	service_range_foreach_match(sr, sc, ua->sr.lower, ua->sr.upper) {
 690		list_for_each_entry(p, &sr->local_publ, local_publ) {
 691			if (scope == p->scope || scope == TIPC_ANY_SCOPE)
 692				tipc_dest_push(dports, 0, p->sk.ref);
 693		}
 694	}
 695	spin_unlock_bh(&sc->lock);
 696exit:
 697	rcu_read_unlock();
 698}
 699
 700/* tipc_nametbl_lookup_mcast_nodes(): look up all destination nodes matching
 701 *                                    the given address. Used in sending node.
 702 * Used on nodes which are sending out a multicast/broadcast message
 703 * Returns a list of nodes, including own node if applicable
 704 */
 705void tipc_nametbl_lookup_mcast_nodes(struct net *net, struct tipc_uaddr *ua,
 706				     struct tipc_nlist *nodes)
 707{
 708	struct service_range *sr;
 709	struct tipc_service *sc;
 710	struct publication *p;
 711
 712	rcu_read_lock();
 713	sc = tipc_service_find(net, ua);
 714	if (!sc)
 715		goto exit;
 716
 717	spin_lock_bh(&sc->lock);
 718	service_range_foreach_match(sr, sc, ua->sr.lower, ua->sr.upper) {
 719		list_for_each_entry(p, &sr->all_publ, all_publ) {
 720			tipc_nlist_add(nodes, p->sk.node);
 721		}
 722	}
 723	spin_unlock_bh(&sc->lock);
 724exit:
 725	rcu_read_unlock();
 726}
 727
 728/* tipc_nametbl_build_group - build list of communication group members
 729 */
 730void tipc_nametbl_build_group(struct net *net, struct tipc_group *grp,
 731			      struct tipc_uaddr *ua)
 732{
 733	struct service_range *sr;
 734	struct tipc_service *sc;
 735	struct publication *p;
 736	struct rb_node *n;
 737
 738	rcu_read_lock();
 739	sc = tipc_service_find(net, ua);
 740	if (!sc)
 741		goto exit;
 742
 743	spin_lock_bh(&sc->lock);
 744	for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
 745		sr = container_of(n, struct service_range, tree_node);
 746		list_for_each_entry(p, &sr->all_publ, all_publ) {
 747			if (p->scope != ua->scope)
 748				continue;
 749			tipc_group_add_member(grp, p->sk.node, p->sk.ref,
 750					      p->sr.lower);
 751		}
 752	}
 753	spin_unlock_bh(&sc->lock);
 754exit:
 755	rcu_read_unlock();
 756}
 757
 758/* tipc_nametbl_publish - add service binding to name table
 759 */
 760struct publication *tipc_nametbl_publish(struct net *net, struct tipc_uaddr *ua,
 761					 struct tipc_socket_addr *sk, u32 key)
 762{
 763	struct name_table *nt = tipc_name_table(net);
 764	struct tipc_net *tn = tipc_net(net);
 765	struct publication *p = NULL;
 766	struct sk_buff *skb = NULL;
 767	u32 rc_dests;
 768
 769	spin_lock_bh(&tn->nametbl_lock);
 770
 771	if (nt->local_publ_count >= TIPC_MAX_PUBL) {
 772		pr_warn("Bind failed, max limit %u reached\n", TIPC_MAX_PUBL);
 773		goto exit;
 774	}
 775
 776	p = tipc_nametbl_insert_publ(net, ua, sk, key);
 777	if (p) {
 778		nt->local_publ_count++;
 779		skb = tipc_named_publish(net, p);
 780	}
 781	rc_dests = nt->rc_dests;
 782exit:
 783	spin_unlock_bh(&tn->nametbl_lock);
 784
 785	if (skb)
 786		tipc_node_broadcast(net, skb, rc_dests);
 787	return p;
 788
 789}
 790
 791/**
 792 * tipc_nametbl_withdraw - withdraw a service binding
 793 * @net: network namespace
 794 * @ua: service address/range being unbound
 795 * @sk: address of the socket being unbound from
 796 * @key: target publication key
 797 */
 798void tipc_nametbl_withdraw(struct net *net, struct tipc_uaddr *ua,
 799			   struct tipc_socket_addr *sk, u32 key)
 800{
 801	struct name_table *nt = tipc_name_table(net);
 802	struct tipc_net *tn = tipc_net(net);
 803	struct sk_buff *skb = NULL;
 804	struct publication *p;
 805	u32 rc_dests;
 806
 807	spin_lock_bh(&tn->nametbl_lock);
 808
 809	p = tipc_nametbl_remove_publ(net, ua, sk, key);
 810	if (p) {
 811		nt->local_publ_count--;
 812		skb = tipc_named_withdraw(net, p);
 813		list_del_init(&p->binding_sock);
 814		kfree_rcu(p, rcu);
 815	}
 816	rc_dests = nt->rc_dests;
 817	spin_unlock_bh(&tn->nametbl_lock);
 818
 819	if (skb)
 820		tipc_node_broadcast(net, skb, rc_dests);
 821}
 822
 823/**
 824 * tipc_nametbl_subscribe - add a subscription object to the name table
 825 * @sub: subscription to add
 826 */
 827bool tipc_nametbl_subscribe(struct tipc_subscription *sub)
 828{
 829	struct tipc_net *tn = tipc_net(sub->net);
 830	u32 type = sub->s.seq.type;
 831	struct tipc_service *sc;
 832	struct tipc_uaddr ua;
 833	bool res = true;
 834
 835	tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_NODE_SCOPE, type,
 836		   sub->s.seq.lower, sub->s.seq.upper);
 837	spin_lock_bh(&tn->nametbl_lock);
 838	sc = tipc_service_find(sub->net, &ua);
 839	if (!sc)
 840		sc = tipc_service_create(sub->net, &ua);
 841	if (sc) {
 842		spin_lock_bh(&sc->lock);
 843		tipc_service_subscribe(sc, sub);
 844		spin_unlock_bh(&sc->lock);
 845	} else {
 846		pr_warn("Failed to subscribe for {%u,%u,%u}\n",
 847			type, sub->s.seq.lower, sub->s.seq.upper);
 848		res = false;
 849	}
 850	spin_unlock_bh(&tn->nametbl_lock);
 851	return res;
 852}
 853
 854/**
 855 * tipc_nametbl_unsubscribe - remove a subscription object from name table
 856 * @sub: subscription to remove
 857 */
 858void tipc_nametbl_unsubscribe(struct tipc_subscription *sub)
 859{
 860	struct tipc_net *tn = tipc_net(sub->net);
 861	struct tipc_service *sc;
 862	struct tipc_uaddr ua;
 863
 864	tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_NODE_SCOPE,
 865		   sub->s.seq.type, sub->s.seq.lower, sub->s.seq.upper);
 866	spin_lock_bh(&tn->nametbl_lock);
 867	sc = tipc_service_find(sub->net, &ua);
 868	if (!sc)
 869		goto exit;
 870
 871	spin_lock_bh(&sc->lock);
 872	list_del_init(&sub->service_list);
 873	tipc_sub_put(sub);
 874
 875	/* Delete service item if no more publications and subscriptions */
 876	if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) {
 877		hlist_del_init_rcu(&sc->service_list);
 878		kfree_rcu(sc, rcu);
 879	}
 880	spin_unlock_bh(&sc->lock);
 881exit:
 882	spin_unlock_bh(&tn->nametbl_lock);
 883}
 884
 885int tipc_nametbl_init(struct net *net)
 886{
 887	struct tipc_net *tn = tipc_net(net);
 888	struct name_table *nt;
 889	int i;
 890
 891	nt = kzalloc(sizeof(*nt), GFP_KERNEL);
 892	if (!nt)
 893		return -ENOMEM;
 894
 895	for (i = 0; i < TIPC_NAMETBL_SIZE; i++)
 896		INIT_HLIST_HEAD(&nt->services[i]);
 897
 898	INIT_LIST_HEAD(&nt->node_scope);
 899	INIT_LIST_HEAD(&nt->cluster_scope);
 900	rwlock_init(&nt->cluster_scope_lock);
 901	tn->nametbl = nt;
 902	spin_lock_init(&tn->nametbl_lock);
 903	return 0;
 904}
 905
 906/**
 907 * tipc_service_delete - purge all publications for a service and delete it
 908 * @net: the associated network namespace
 909 * @sc: tipc_service to delete
 910 */
 911static void tipc_service_delete(struct net *net, struct tipc_service *sc)
 912{
 913	struct service_range *sr, *tmpr;
 914	struct publication *p, *tmp;
 915
 916	spin_lock_bh(&sc->lock);
 917	rbtree_postorder_for_each_entry_safe(sr, tmpr, &sc->ranges, tree_node) {
 918		list_for_each_entry_safe(p, tmp, &sr->all_publ, all_publ) {
 919			tipc_service_remove_publ(sr, &p->sk, p->key);
 920			kfree_rcu(p, rcu);
 921		}
 922		rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks);
 923		kfree(sr);
 924	}
 925	hlist_del_init_rcu(&sc->service_list);
 926	spin_unlock_bh(&sc->lock);
 927	kfree_rcu(sc, rcu);
 928}
 929
 930void tipc_nametbl_stop(struct net *net)
 931{
 932	struct name_table *nt = tipc_name_table(net);
 933	struct tipc_net *tn = tipc_net(net);
 934	struct hlist_head *service_head;
 935	struct tipc_service *service;
 936	u32 i;
 937
 938	/* Verify name table is empty and purge any lingering
 939	 * publications, then release the name table
 940	 */
 941	spin_lock_bh(&tn->nametbl_lock);
 942	for (i = 0; i < TIPC_NAMETBL_SIZE; i++) {
 943		if (hlist_empty(&nt->services[i]))
 944			continue;
 945		service_head = &nt->services[i];
 946		hlist_for_each_entry_rcu(service, service_head, service_list) {
 947			tipc_service_delete(net, service);
 948		}
 949	}
 950	spin_unlock_bh(&tn->nametbl_lock);
 951
 952	synchronize_net();
 953	kfree(nt);
 954}
 955
 956static int __tipc_nl_add_nametable_publ(struct tipc_nl_msg *msg,
 957					struct tipc_service *service,
 958					struct service_range *sr,
 959					u32 *last_key)
 960{
 961	struct publication *p;
 962	struct nlattr *attrs;
 963	struct nlattr *b;
 964	void *hdr;
 965
 966	if (*last_key) {
 967		list_for_each_entry(p, &sr->all_publ, all_publ)
 968			if (p->key == *last_key)
 969				break;
 970		if (p->key != *last_key)
 971			return -EPIPE;
 972	} else {
 973		p = list_first_entry(&sr->all_publ,
 974				     struct publication,
 975				     all_publ);
 976	}
 977
 978	list_for_each_entry_from(p, &sr->all_publ, all_publ) {
 979		*last_key = p->key;
 980
 981		hdr = genlmsg_put(msg->skb, msg->portid, msg->seq,
 982				  &tipc_genl_family, NLM_F_MULTI,
 983				  TIPC_NL_NAME_TABLE_GET);
 984		if (!hdr)
 985			return -EMSGSIZE;
 986
 987		attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE);
 988		if (!attrs)
 989			goto msg_full;
 990
 991		b = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE_PUBL);
 992		if (!b)
 993			goto attr_msg_full;
 994
 995		if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_TYPE, service->type))
 996			goto publ_msg_full;
 997		if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_LOWER, sr->lower))
 998			goto publ_msg_full;
 999		if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_UPPER, sr->upper))
1000			goto publ_msg_full;
1001		if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_SCOPE, p->scope))
1002			goto publ_msg_full;
1003		if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_NODE, p->sk.node))
1004			goto publ_msg_full;
1005		if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_REF, p->sk.ref))
1006			goto publ_msg_full;
1007		if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_KEY, p->key))
1008			goto publ_msg_full;
1009
1010		nla_nest_end(msg->skb, b);
1011		nla_nest_end(msg->skb, attrs);
1012		genlmsg_end(msg->skb, hdr);
1013	}
1014	*last_key = 0;
1015
1016	return 0;
1017
1018publ_msg_full:
1019	nla_nest_cancel(msg->skb, b);
1020attr_msg_full:
1021	nla_nest_cancel(msg->skb, attrs);
1022msg_full:
1023	genlmsg_cancel(msg->skb, hdr);
1024
1025	return -EMSGSIZE;
1026}
1027
1028static int __tipc_nl_service_range_list(struct tipc_nl_msg *msg,
1029					struct tipc_service *sc,
1030					u32 *last_lower, u32 *last_key)
1031{
1032	struct service_range *sr;
1033	struct rb_node *n;
1034	int err;
1035
1036	for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
1037		sr = container_of(n, struct service_range, tree_node);
1038		if (sr->lower < *last_lower)
1039			continue;
1040		err = __tipc_nl_add_nametable_publ(msg, sc, sr, last_key);
1041		if (err) {
1042			*last_lower = sr->lower;
1043			return err;
1044		}
1045	}
1046	*last_lower = 0;
1047	return 0;
1048}
1049
1050static int tipc_nl_service_list(struct net *net, struct tipc_nl_msg *msg,
1051				u32 *last_type, u32 *last_lower, u32 *last_key)
1052{
1053	struct tipc_net *tn = tipc_net(net);
1054	struct tipc_service *service = NULL;
1055	struct hlist_head *head;
1056	struct tipc_uaddr ua;
1057	int err;
1058	int i;
1059
1060	if (*last_type)
1061		i = hash(*last_type);
1062	else
1063		i = 0;
1064
1065	for (; i < TIPC_NAMETBL_SIZE; i++) {
1066		head = &tn->nametbl->services[i];
1067
1068		if (*last_type ||
1069		    (!i && *last_key && (*last_lower == *last_key))) {
1070			tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_NODE_SCOPE,
1071				   *last_type, *last_lower, *last_lower);
1072			service = tipc_service_find(net, &ua);
1073			if (!service)
1074				return -EPIPE;
1075		} else {
1076			hlist_for_each_entry_rcu(service, head, service_list)
1077				break;
1078			if (!service)
1079				continue;
1080		}
1081
1082		hlist_for_each_entry_from_rcu(service, service_list) {
1083			spin_lock_bh(&service->lock);
1084			err = __tipc_nl_service_range_list(msg, service,
1085							   last_lower,
1086							   last_key);
1087
1088			if (err) {
1089				*last_type = service->type;
1090				spin_unlock_bh(&service->lock);
1091				return err;
1092			}
1093			spin_unlock_bh(&service->lock);
1094		}
1095		*last_type = 0;
1096	}
1097	return 0;
1098}
1099
1100int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb)
1101{
1102	struct net *net = sock_net(skb->sk);
1103	u32 last_type = cb->args[0];
1104	u32 last_lower = cb->args[1];
1105	u32 last_key = cb->args[2];
1106	int done = cb->args[3];
1107	struct tipc_nl_msg msg;
1108	int err;
1109
1110	if (done)
1111		return 0;
1112
1113	msg.skb = skb;
1114	msg.portid = NETLINK_CB(cb->skb).portid;
1115	msg.seq = cb->nlh->nlmsg_seq;
1116
1117	rcu_read_lock();
1118	err = tipc_nl_service_list(net, &msg, &last_type,
1119				   &last_lower, &last_key);
1120	if (!err) {
1121		done = 1;
1122	} else if (err != -EMSGSIZE) {
1123		/* We never set seq or call nl_dump_check_consistent() this
1124		 * means that setting prev_seq here will cause the consistence
1125		 * check to fail in the netlink callback handler. Resulting in
1126		 * the NLMSG_DONE message having the NLM_F_DUMP_INTR flag set if
1127		 * we got an error.
1128		 */
1129		cb->prev_seq = 1;
1130	}
1131	rcu_read_unlock();
1132
1133	cb->args[0] = last_type;
1134	cb->args[1] = last_lower;
1135	cb->args[2] = last_key;
1136	cb->args[3] = done;
1137
1138	return skb->len;
1139}
1140
1141struct tipc_dest *tipc_dest_find(struct list_head *l, u32 node, u32 port)
1142{
1143	struct tipc_dest *dst;
1144
1145	list_for_each_entry(dst, l, list) {
1146		if (dst->node == node && dst->port == port)
1147			return dst;
1148	}
1149	return NULL;
1150}
1151
1152bool tipc_dest_push(struct list_head *l, u32 node, u32 port)
1153{
1154	struct tipc_dest *dst;
1155
1156	if (tipc_dest_find(l, node, port))
1157		return false;
1158
1159	dst = kmalloc(sizeof(*dst), GFP_ATOMIC);
1160	if (unlikely(!dst))
1161		return false;
1162	dst->node = node;
1163	dst->port = port;
1164	list_add(&dst->list, l);
1165	return true;
1166}
1167
1168bool tipc_dest_pop(struct list_head *l, u32 *node, u32 *port)
1169{
1170	struct tipc_dest *dst;
1171
1172	if (list_empty(l))
1173		return false;
1174	dst = list_first_entry(l, typeof(*dst), list);
1175	if (port)
1176		*port = dst->port;
1177	if (node)
1178		*node = dst->node;
1179	list_del(&dst->list);
1180	kfree(dst);
1181	return true;
1182}
1183
1184bool tipc_dest_del(struct list_head *l, u32 node, u32 port)
1185{
1186	struct tipc_dest *dst;
1187
1188	dst = tipc_dest_find(l, node, port);
1189	if (!dst)
1190		return false;
1191	list_del(&dst->list);
1192	kfree(dst);
1193	return true;
1194}
1195
1196void tipc_dest_list_purge(struct list_head *l)
1197{
1198	struct tipc_dest *dst, *tmp;
1199
1200	list_for_each_entry_safe(dst, tmp, l, list) {
1201		list_del(&dst->list);
1202		kfree(dst);
1203	}
1204}
1205
1206int tipc_dest_list_len(struct list_head *l)
1207{
1208	struct tipc_dest *dst;
1209	int i = 0;
1210
1211	list_for_each_entry(dst, l, list) {
1212		i++;
1213	}
1214	return i;
1215}