1/*
   2 * net/tipc/node.c: TIPC node management routines
   3 *
   4 * Copyright (c) 2000-2006, 2012-2016, Ericsson AB
   5 * Copyright (c) 2005-2006, 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 "core.h"
  38#include "link.h"
  39#include "node.h"
  40#include "name_distr.h"
  41#include "socket.h"
  42#include "bcast.h"
  43#include "monitor.h"
  44#include "discover.h"
  45#include "netlink.h"
 
  46
  47#define INVALID_NODE_SIG	0x10000
 
  48
  49/* Flags used to take different actions according to flag type
  50 * TIPC_NOTIFY_NODE_DOWN: notify node is down
  51 * TIPC_NOTIFY_NODE_UP: notify node is up
  52 * TIPC_DISTRIBUTE_NAME: publish or withdraw link state name type
  53 */
  54enum {
  55	TIPC_NOTIFY_NODE_DOWN		= (1 << 3),
  56	TIPC_NOTIFY_NODE_UP		= (1 << 4),
  57	TIPC_NOTIFY_LINK_UP		= (1 << 6),
  58	TIPC_NOTIFY_LINK_DOWN		= (1 << 7)
  59};
  60
  61struct tipc_link_entry {
  62	struct tipc_link *link;
  63	spinlock_t lock; /* per link */
  64	u32 mtu;
  65	struct sk_buff_head inputq;
  66	struct tipc_media_addr maddr;
  67};
  68
  69struct tipc_bclink_entry {
  70	struct tipc_link *link;
  71	struct sk_buff_head inputq1;
  72	struct sk_buff_head arrvq;
  73	struct sk_buff_head inputq2;
  74	struct sk_buff_head namedq;
  75};
  76
  77/**
  78 * struct tipc_node - TIPC node structure
  79 * @addr: network address of node
  80 * @ref: reference counter to node object
  81 * @lock: rwlock governing access to structure
  82 * @net: the applicable net namespace
  83 * @hash: links to adjacent nodes in unsorted hash chain
  84 * @inputq: pointer to input queue containing messages for msg event
  85 * @namedq: pointer to name table input queue with name table messages
  86 * @active_links: bearer ids of active links, used as index into links[] array
  87 * @links: array containing references to all links to node
  88 * @action_flags: bit mask of different types of node actions
  89 * @state: connectivity state vs peer node
  90 * @sync_point: sequence number where synch/failover is finished
  91 * @list: links to adjacent nodes in sorted list of cluster's nodes
  92 * @working_links: number of working links to node (both active and standby)
  93 * @link_cnt: number of links to node
  94 * @capabilities: bitmap, indicating peer node's functional capabilities
  95 * @signature: node instance identifier
  96 * @link_id: local and remote bearer ids of changing link, if any
  97 * @publ_list: list of publications
  98 * @rcu: rcu struct for tipc_node
 
  99 */
 100struct tipc_node {
 101	u32 addr;
 102	struct kref kref;
 103	rwlock_t lock;
 104	struct net *net;
 105	struct hlist_node hash;
 106	int active_links[2];
 107	struct tipc_link_entry links[MAX_BEARERS];
 108	struct tipc_bclink_entry bc_entry;
 109	int action_flags;
 110	struct list_head list;
 111	int state;
 
 112	u16 sync_point;
 113	int link_cnt;
 114	u16 working_links;
 115	u16 capabilities;
 116	u32 signature;
 117	u32 link_id;
 118	u8 peer_id[16];
 119	struct list_head publ_list;
 120	struct list_head conn_sks;
 121	unsigned long keepalive_intv;
 122	struct timer_list timer;
 123	struct rcu_head rcu;
 
 124};
 125
 126/* Node FSM states and events:
 127 */
 128enum {
 129	SELF_DOWN_PEER_DOWN    = 0xdd,
 130	SELF_UP_PEER_UP        = 0xaa,
 131	SELF_DOWN_PEER_LEAVING = 0xd1,
 132	SELF_UP_PEER_COMING    = 0xac,
 133	SELF_COMING_PEER_UP    = 0xca,
 134	SELF_LEAVING_PEER_DOWN = 0x1d,
 135	NODE_FAILINGOVER       = 0xf0,
 136	NODE_SYNCHING          = 0xcc
 137};
 138
 139enum {
 140	SELF_ESTABL_CONTACT_EVT = 0xece,
 141	SELF_LOST_CONTACT_EVT   = 0x1ce,
 142	PEER_ESTABL_CONTACT_EVT = 0x9ece,
 143	PEER_LOST_CONTACT_EVT   = 0x91ce,
 144	NODE_FAILOVER_BEGIN_EVT = 0xfbe,
 145	NODE_FAILOVER_END_EVT   = 0xfee,
 146	NODE_SYNCH_BEGIN_EVT    = 0xcbe,
 147	NODE_SYNCH_END_EVT      = 0xcee
 148};
 149
 150static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
 151				  struct sk_buff_head *xmitq,
 152				  struct tipc_media_addr **maddr);
 153static void tipc_node_link_down(struct tipc_node *n, int bearer_id,
 154				bool delete);
 155static void node_lost_contact(struct tipc_node *n, struct sk_buff_head *inputq);
 156static void tipc_node_delete(struct tipc_node *node);
 157static void tipc_node_timeout(struct timer_list *t);
 158static void tipc_node_fsm_evt(struct tipc_node *n, int evt);
 159static struct tipc_node *tipc_node_find(struct net *net, u32 addr);
 160static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id);
 161static void tipc_node_put(struct tipc_node *node);
 162static bool node_is_up(struct tipc_node *n);
 
 163
 164struct tipc_sock_conn {
 165	u32 port;
 166	u32 peer_port;
 167	u32 peer_node;
 168	struct list_head list;
 169};
 170
 171static struct tipc_link *node_active_link(struct tipc_node *n, int sel)
 172{
 173	int bearer_id = n->active_links[sel & 1];
 174
 175	if (unlikely(bearer_id == INVALID_BEARER_ID))
 176		return NULL;
 177
 178	return n->links[bearer_id].link;
 179}
 180
 181int tipc_node_get_mtu(struct net *net, u32 addr, u32 sel)
 182{
 183	struct tipc_node *n;
 184	int bearer_id;
 185	unsigned int mtu = MAX_MSG_SIZE;
 186
 187	n = tipc_node_find(net, addr);
 188	if (unlikely(!n))
 189		return mtu;
 190
 191	bearer_id = n->active_links[sel & 1];
 192	if (likely(bearer_id != INVALID_BEARER_ID))
 193		mtu = n->links[bearer_id].mtu;
 194	tipc_node_put(n);
 195	return mtu;
 196}
 197
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 198u16 tipc_node_get_capabilities(struct net *net, u32 addr)
 199{
 200	struct tipc_node *n;
 201	u16 caps;
 202
 203	n = tipc_node_find(net, addr);
 204	if (unlikely(!n))
 205		return TIPC_NODE_CAPABILITIES;
 206	caps = n->capabilities;
 207	tipc_node_put(n);
 208	return caps;
 209}
 210
 211static void tipc_node_kref_release(struct kref *kref)
 212{
 213	struct tipc_node *n = container_of(kref, struct tipc_node, kref);
 214
 215	kfree(n->bc_entry.link);
 216	kfree_rcu(n, rcu);
 217}
 218
 219static void tipc_node_put(struct tipc_node *node)
 220{
 221	kref_put(&node->kref, tipc_node_kref_release);
 222}
 223
 224static void tipc_node_get(struct tipc_node *node)
 225{
 226	kref_get(&node->kref);
 227}
 228
 229/*
 230 * tipc_node_find - locate specified node object, if it exists
 231 */
 232static struct tipc_node *tipc_node_find(struct net *net, u32 addr)
 233{
 234	struct tipc_net *tn = tipc_net(net);
 235	struct tipc_node *node;
 236	unsigned int thash = tipc_hashfn(addr);
 237
 238	rcu_read_lock();
 239	hlist_for_each_entry_rcu(node, &tn->node_htable[thash], hash) {
 240		if (node->addr != addr)
 241			continue;
 242		if (!kref_get_unless_zero(&node->kref))
 243			node = NULL;
 244		break;
 245	}
 246	rcu_read_unlock();
 247	return node;
 248}
 249
 250/* tipc_node_find_by_id - locate specified node object by its 128-bit id
 251 * Note: this function is called only when a discovery request failed
 252 * to find the node by its 32-bit id, and is not time critical
 253 */
 254static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id)
 255{
 256	struct tipc_net *tn = tipc_net(net);
 257	struct tipc_node *n;
 258	bool found = false;
 259
 260	rcu_read_lock();
 261	list_for_each_entry_rcu(n, &tn->node_list, list) {
 262		read_lock_bh(&n->lock);
 263		if (!memcmp(id, n->peer_id, 16) &&
 264		    kref_get_unless_zero(&n->kref))
 265			found = true;
 266		read_unlock_bh(&n->lock);
 267		if (found)
 268			break;
 269	}
 270	rcu_read_unlock();
 271	return found ? n : NULL;
 272}
 273
 274static void tipc_node_read_lock(struct tipc_node *n)
 275{
 276	read_lock_bh(&n->lock);
 277}
 278
 279static void tipc_node_read_unlock(struct tipc_node *n)
 280{
 281	read_unlock_bh(&n->lock);
 282}
 283
 284static void tipc_node_write_lock(struct tipc_node *n)
 285{
 286	write_lock_bh(&n->lock);
 287}
 288
 289static void tipc_node_write_unlock_fast(struct tipc_node *n)
 290{
 291	write_unlock_bh(&n->lock);
 292}
 293
 294static void tipc_node_write_unlock(struct tipc_node *n)
 295{
 296	struct net *net = n->net;
 297	u32 addr = 0;
 298	u32 flags = n->action_flags;
 299	u32 link_id = 0;
 300	u32 bearer_id;
 301	struct list_head *publ_list;
 302
 303	if (likely(!flags)) {
 304		write_unlock_bh(&n->lock);
 305		return;
 306	}
 307
 308	addr = n->addr;
 309	link_id = n->link_id;
 310	bearer_id = link_id & 0xffff;
 311	publ_list = &n->publ_list;
 312
 313	n->action_flags &= ~(TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP |
 314			     TIPC_NOTIFY_LINK_DOWN | TIPC_NOTIFY_LINK_UP);
 315
 316	write_unlock_bh(&n->lock);
 317
 318	if (flags & TIPC_NOTIFY_NODE_DOWN)
 319		tipc_publ_notify(net, publ_list, addr);
 320
 321	if (flags & TIPC_NOTIFY_NODE_UP)
 322		tipc_named_node_up(net, addr);
 323
 324	if (flags & TIPC_NOTIFY_LINK_UP) {
 325		tipc_mon_peer_up(net, addr, bearer_id);
 326		tipc_nametbl_publish(net, TIPC_LINK_STATE, addr, addr,
 327				     TIPC_NODE_SCOPE, link_id, link_id);
 328	}
 329	if (flags & TIPC_NOTIFY_LINK_DOWN) {
 330		tipc_mon_peer_down(net, addr, bearer_id);
 331		tipc_nametbl_withdraw(net, TIPC_LINK_STATE, addr,
 332				      addr, link_id);
 333	}
 334}
 335
 336static struct tipc_node *tipc_node_create(struct net *net, u32 addr,
 337					  u8 *peer_id, u16 capabilities)
 338{
 339	struct tipc_net *tn = net_generic(net, tipc_net_id);
 340	struct tipc_node *n, *temp_node;
 
 
 341	int i;
 342
 343	spin_lock_bh(&tn->node_list_lock);
 344	n = tipc_node_find(net, addr);
 345	if (n) {
 
 
 346		/* Same node may come back with new capabilities */
 
 347		n->capabilities = capabilities;
 
 
 
 
 
 
 
 
 
 
 
 
 348		goto exit;
 349	}
 350	n = kzalloc(sizeof(*n), GFP_ATOMIC);
 351	if (!n) {
 352		pr_warn("Node creation failed, no memory\n");
 353		goto exit;
 354	}
 355	n->addr = addr;
 356	memcpy(&n->peer_id, peer_id, 16);
 357	n->net = net;
 358	n->capabilities = capabilities;
 359	kref_init(&n->kref);
 360	rwlock_init(&n->lock);
 361	INIT_HLIST_NODE(&n->hash);
 362	INIT_LIST_HEAD(&n->list);
 363	INIT_LIST_HEAD(&n->publ_list);
 364	INIT_LIST_HEAD(&n->conn_sks);
 365	skb_queue_head_init(&n->bc_entry.namedq);
 366	skb_queue_head_init(&n->bc_entry.inputq1);
 367	__skb_queue_head_init(&n->bc_entry.arrvq);
 368	skb_queue_head_init(&n->bc_entry.inputq2);
 369	for (i = 0; i < MAX_BEARERS; i++)
 370		spin_lock_init(&n->links[i].lock);
 371	n->state = SELF_DOWN_PEER_LEAVING;
 
 372	n->signature = INVALID_NODE_SIG;
 373	n->active_links[0] = INVALID_BEARER_ID;
 374	n->active_links[1] = INVALID_BEARER_ID;
 375	if (!tipc_link_bc_create(net, tipc_own_addr(net),
 376				 addr, U16_MAX,
 377				 tipc_link_window(tipc_bc_sndlink(net)),
 378				 n->capabilities,
 379				 &n->bc_entry.inputq1,
 380				 &n->bc_entry.namedq,
 381				 tipc_bc_sndlink(net),
 382				 &n->bc_entry.link)) {
 383		pr_warn("Broadcast rcv link creation failed, no memory\n");
 384		kfree(n);
 385		n = NULL;
 386		goto exit;
 387	}
 388	tipc_node_get(n);
 389	timer_setup(&n->timer, tipc_node_timeout, 0);
 390	n->keepalive_intv = U32_MAX;
 391	hlist_add_head_rcu(&n->hash, &tn->node_htable[tipc_hashfn(addr)]);
 392	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
 393		if (n->addr < temp_node->addr)
 394			break;
 395	}
 396	list_add_tail_rcu(&n->list, &temp_node->list);
 
 
 
 
 
 
 397exit:
 398	spin_unlock_bh(&tn->node_list_lock);
 399	return n;
 400}
 401
 402static void tipc_node_calculate_timer(struct tipc_node *n, struct tipc_link *l)
 403{
 404	unsigned long tol = tipc_link_tolerance(l);
 405	unsigned long intv = ((tol / 4) > 500) ? 500 : tol / 4;
 406
 407	/* Link with lowest tolerance determines timer interval */
 408	if (intv < n->keepalive_intv)
 409		n->keepalive_intv = intv;
 410
 411	/* Ensure link's abort limit corresponds to current tolerance */
 412	tipc_link_set_abort_limit(l, tol / n->keepalive_intv);
 413}
 414
 415static void tipc_node_delete(struct tipc_node *node)
 416{
 417	list_del_rcu(&node->list);
 418	hlist_del_rcu(&node->hash);
 419	tipc_node_put(node);
 
 
 
 
 
 
 420
 421	del_timer_sync(&node->timer);
 422	tipc_node_put(node);
 423}
 424
 425void tipc_node_stop(struct net *net)
 426{
 427	struct tipc_net *tn = tipc_net(net);
 428	struct tipc_node *node, *t_node;
 429
 430	spin_lock_bh(&tn->node_list_lock);
 431	list_for_each_entry_safe(node, t_node, &tn->node_list, list)
 432		tipc_node_delete(node);
 433	spin_unlock_bh(&tn->node_list_lock);
 434}
 435
 436void tipc_node_subscribe(struct net *net, struct list_head *subscr, u32 addr)
 437{
 438	struct tipc_node *n;
 439
 440	if (in_own_node(net, addr))
 441		return;
 442
 443	n = tipc_node_find(net, addr);
 444	if (!n) {
 445		pr_warn("Node subscribe rejected, unknown node 0x%x\n", addr);
 446		return;
 447	}
 448	tipc_node_write_lock(n);
 449	list_add_tail(subscr, &n->publ_list);
 450	tipc_node_write_unlock_fast(n);
 451	tipc_node_put(n);
 452}
 453
 454void tipc_node_unsubscribe(struct net *net, struct list_head *subscr, u32 addr)
 455{
 456	struct tipc_node *n;
 457
 458	if (in_own_node(net, addr))
 459		return;
 460
 461	n = tipc_node_find(net, addr);
 462	if (!n) {
 463		pr_warn("Node unsubscribe rejected, unknown node 0x%x\n", addr);
 464		return;
 465	}
 466	tipc_node_write_lock(n);
 467	list_del_init(subscr);
 468	tipc_node_write_unlock_fast(n);
 469	tipc_node_put(n);
 470}
 471
 472int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port)
 473{
 474	struct tipc_node *node;
 475	struct tipc_sock_conn *conn;
 476	int err = 0;
 477
 478	if (in_own_node(net, dnode))
 479		return 0;
 480
 481	node = tipc_node_find(net, dnode);
 482	if (!node) {
 483		pr_warn("Connecting sock to node 0x%x failed\n", dnode);
 484		return -EHOSTUNREACH;
 485	}
 486	conn = kmalloc(sizeof(*conn), GFP_ATOMIC);
 487	if (!conn) {
 488		err = -EHOSTUNREACH;
 489		goto exit;
 490	}
 491	conn->peer_node = dnode;
 492	conn->port = port;
 493	conn->peer_port = peer_port;
 494
 495	tipc_node_write_lock(node);
 496	list_add_tail(&conn->list, &node->conn_sks);
 497	tipc_node_write_unlock(node);
 498exit:
 499	tipc_node_put(node);
 500	return err;
 501}
 502
 503void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port)
 504{
 505	struct tipc_node *node;
 506	struct tipc_sock_conn *conn, *safe;
 507
 508	if (in_own_node(net, dnode))
 509		return;
 510
 511	node = tipc_node_find(net, dnode);
 512	if (!node)
 513		return;
 514
 515	tipc_node_write_lock(node);
 516	list_for_each_entry_safe(conn, safe, &node->conn_sks, list) {
 517		if (port != conn->port)
 518			continue;
 519		list_del(&conn->list);
 520		kfree(conn);
 521	}
 522	tipc_node_write_unlock(node);
 523	tipc_node_put(node);
 524}
 525
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 526/* tipc_node_timeout - handle expiration of node timer
 527 */
 528static void tipc_node_timeout(struct timer_list *t)
 529{
 530	struct tipc_node *n = from_timer(n, t, timer);
 531	struct tipc_link_entry *le;
 532	struct sk_buff_head xmitq;
 
 533	int bearer_id;
 534	int rc = 0;
 535
 
 
 
 
 
 
 
 536	__skb_queue_head_init(&xmitq);
 537
 538	for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
 
 
 
 
 
 
 539		tipc_node_read_lock(n);
 540		le = &n->links[bearer_id];
 541		spin_lock_bh(&le->lock);
 542		if (le->link) {
 
 543			/* Link tolerance may change asynchronously: */
 544			tipc_node_calculate_timer(n, le->link);
 545			rc = tipc_link_timeout(le->link, &xmitq);
 
 
 546		}
 547		spin_unlock_bh(&le->lock);
 548		tipc_node_read_unlock(n);
 549		tipc_bearer_xmit(n->net, bearer_id, &xmitq, &le->maddr);
 550		if (rc & TIPC_LINK_DOWN_EVT)
 551			tipc_node_link_down(n, bearer_id, false);
 552	}
 553	mod_timer(&n->timer, jiffies + msecs_to_jiffies(n->keepalive_intv));
 554}
 555
 556/**
 557 * __tipc_node_link_up - handle addition of link
 558 * Node lock must be held by caller
 559 * Link becomes active (alone or shared) or standby, depending on its priority.
 560 */
 561static void __tipc_node_link_up(struct tipc_node *n, int bearer_id,
 562				struct sk_buff_head *xmitq)
 563{
 564	int *slot0 = &n->active_links[0];
 565	int *slot1 = &n->active_links[1];
 566	struct tipc_link *ol = node_active_link(n, 0);
 567	struct tipc_link *nl = n->links[bearer_id].link;
 568
 569	if (!nl || tipc_link_is_up(nl))
 570		return;
 571
 572	tipc_link_fsm_evt(nl, LINK_ESTABLISH_EVT);
 573	if (!tipc_link_is_up(nl))
 574		return;
 575
 576	n->working_links++;
 577	n->action_flags |= TIPC_NOTIFY_LINK_UP;
 578	n->link_id = tipc_link_id(nl);
 579
 580	/* Leave room for tunnel header when returning 'mtu' to users: */
 581	n->links[bearer_id].mtu = tipc_link_mtu(nl) - INT_H_SIZE;
 582
 583	tipc_bearer_add_dest(n->net, bearer_id, n->addr);
 584	tipc_bcast_inc_bearer_dst_cnt(n->net, bearer_id);
 585
 586	pr_debug("Established link <%s> on network plane %c\n",
 587		 tipc_link_name(nl), tipc_link_plane(nl));
 
 588
 589	/* Ensure that a STATE message goes first */
 590	tipc_link_build_state_msg(nl, xmitq);
 591
 592	/* First link? => give it both slots */
 593	if (!ol) {
 594		*slot0 = bearer_id;
 595		*slot1 = bearer_id;
 596		tipc_node_fsm_evt(n, SELF_ESTABL_CONTACT_EVT);
 597		n->action_flags |= TIPC_NOTIFY_NODE_UP;
 598		tipc_link_set_active(nl, true);
 599		tipc_bcast_add_peer(n->net, nl, xmitq);
 600		return;
 601	}
 602
 603	/* Second link => redistribute slots */
 604	if (tipc_link_prio(nl) > tipc_link_prio(ol)) {
 605		pr_debug("Old link <%s> becomes standby\n", tipc_link_name(ol));
 606		*slot0 = bearer_id;
 607		*slot1 = bearer_id;
 608		tipc_link_set_active(nl, true);
 609		tipc_link_set_active(ol, false);
 610	} else if (tipc_link_prio(nl) == tipc_link_prio(ol)) {
 611		tipc_link_set_active(nl, true);
 612		*slot1 = bearer_id;
 613	} else {
 614		pr_debug("New link <%s> is standby\n", tipc_link_name(nl));
 615	}
 616
 617	/* Prepare synchronization with first link */
 618	tipc_link_tnl_prepare(ol, nl, SYNCH_MSG, xmitq);
 619}
 620
 621/**
 622 * tipc_node_link_up - handle addition of link
 623 *
 624 * Link becomes active (alone or shared) or standby, depending on its priority.
 625 */
 626static void tipc_node_link_up(struct tipc_node *n, int bearer_id,
 627			      struct sk_buff_head *xmitq)
 628{
 629	struct tipc_media_addr *maddr;
 630
 631	tipc_node_write_lock(n);
 632	__tipc_node_link_up(n, bearer_id, xmitq);
 633	maddr = &n->links[bearer_id].maddr;
 634	tipc_bearer_xmit(n->net, bearer_id, xmitq, maddr);
 635	tipc_node_write_unlock(n);
 636}
 637
 638/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 639 * __tipc_node_link_down - handle loss of link
 640 */
 641static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
 642				  struct sk_buff_head *xmitq,
 643				  struct tipc_media_addr **maddr)
 644{
 645	struct tipc_link_entry *le = &n->links[*bearer_id];
 646	int *slot0 = &n->active_links[0];
 647	int *slot1 = &n->active_links[1];
 648	int i, highest = 0, prio;
 649	struct tipc_link *l, *_l, *tnl;
 650
 651	l = n->links[*bearer_id].link;
 652	if (!l || tipc_link_is_reset(l))
 653		return;
 654
 655	n->working_links--;
 656	n->action_flags |= TIPC_NOTIFY_LINK_DOWN;
 657	n->link_id = tipc_link_id(l);
 658
 659	tipc_bearer_remove_dest(n->net, *bearer_id, n->addr);
 660
 661	pr_debug("Lost link <%s> on network plane %c\n",
 662		 tipc_link_name(l), tipc_link_plane(l));
 663
 664	/* Select new active link if any available */
 665	*slot0 = INVALID_BEARER_ID;
 666	*slot1 = INVALID_BEARER_ID;
 667	for (i = 0; i < MAX_BEARERS; i++) {
 668		_l = n->links[i].link;
 669		if (!_l || !tipc_link_is_up(_l))
 670			continue;
 671		if (_l == l)
 672			continue;
 673		prio = tipc_link_prio(_l);
 674		if (prio < highest)
 675			continue;
 676		if (prio > highest) {
 677			highest = prio;
 678			*slot0 = i;
 679			*slot1 = i;
 680			continue;
 681		}
 682		*slot1 = i;
 683	}
 684
 685	if (!node_is_up(n)) {
 686		if (tipc_link_peer_is_down(l))
 687			tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
 688		tipc_node_fsm_evt(n, SELF_LOST_CONTACT_EVT);
 
 689		tipc_link_fsm_evt(l, LINK_RESET_EVT);
 690		tipc_link_reset(l);
 691		tipc_link_build_reset_msg(l, xmitq);
 692		*maddr = &n->links[*bearer_id].maddr;
 693		node_lost_contact(n, &le->inputq);
 694		tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
 695		return;
 696	}
 697	tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
 698
 699	/* There is still a working link => initiate failover */
 700	*bearer_id = n->active_links[0];
 701	tnl = n->links[*bearer_id].link;
 702	tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
 703	tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
 704	n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
 705	tipc_link_tnl_prepare(l, tnl, FAILOVER_MSG, xmitq);
 
 706	tipc_link_reset(l);
 707	tipc_link_fsm_evt(l, LINK_RESET_EVT);
 708	tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
 709	tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
 710	*maddr = &n->links[*bearer_id].maddr;
 711}
 712
 713static void tipc_node_link_down(struct tipc_node *n, int bearer_id, bool delete)
 714{
 715	struct tipc_link_entry *le = &n->links[bearer_id];
 
 716	struct tipc_link *l = le->link;
 717	struct tipc_media_addr *maddr;
 718	struct sk_buff_head xmitq;
 719	int old_bearer_id = bearer_id;
 
 720
 721	if (!l)
 722		return;
 723
 724	__skb_queue_head_init(&xmitq);
 725
 726	tipc_node_write_lock(n);
 727	if (!tipc_link_is_establishing(l)) {
 728		__tipc_node_link_down(n, &bearer_id, &xmitq, &maddr);
 729		if (delete) {
 730			kfree(l);
 731			le->link = NULL;
 732			n->link_cnt--;
 733		}
 734	} else {
 735		/* Defuse pending tipc_node_link_up() */
 
 736		tipc_link_fsm_evt(l, LINK_RESET_EVT);
 737	}
 
 
 
 
 
 
 738	tipc_node_write_unlock(n);
 739	if (delete)
 740		tipc_mon_remove_peer(n->net, n->addr, old_bearer_id);
 741	tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr);
 
 742	tipc_sk_rcv(n->net, &le->inputq);
 743}
 744
 745static bool node_is_up(struct tipc_node *n)
 746{
 747	return n->active_links[0] != INVALID_BEARER_ID;
 748}
 749
 750bool tipc_node_is_up(struct net *net, u32 addr)
 751{
 752	struct tipc_node *n;
 753	bool retval = false;
 754
 755	if (in_own_node(net, addr))
 756		return true;
 757
 758	n = tipc_node_find(net, addr);
 759	if (!n)
 760		return false;
 761	retval = node_is_up(n);
 762	tipc_node_put(n);
 763	return retval;
 764}
 765
 766static u32 tipc_node_suggest_addr(struct net *net, u32 addr)
 767{
 768	struct tipc_node *n;
 769
 770	addr ^= tipc_net(net)->random;
 771	while ((n = tipc_node_find(net, addr))) {
 772		tipc_node_put(n);
 773		addr++;
 774	}
 775	return addr;
 776}
 777
 778/* tipc_node_try_addr(): Check if addr can be used by peer, suggest other if not
 
 779 */
 780u32 tipc_node_try_addr(struct net *net, u8 *id, u32 addr)
 781{
 782	struct tipc_net *tn = tipc_net(net);
 783	struct tipc_node *n;
 784
 785	/* Suggest new address if some other peer is using this one */
 786	n = tipc_node_find(net, addr);
 787	if (n) {
 788		if (!memcmp(n->peer_id, id, NODE_ID_LEN))
 789			addr = 0;
 790		tipc_node_put(n);
 791		if (!addr)
 792			return 0;
 793		return tipc_node_suggest_addr(net, addr);
 794	}
 795
 796	/* Suggest previously used address if peer is known */
 797	n = tipc_node_find_by_id(net, id);
 798	if (n) {
 799		addr = n->addr;
 800		tipc_node_put(n);
 
 801	}
 802	/* Even this node may be in trial phase */
 
 803	if (tn->trial_addr == addr)
 804		return tipc_node_suggest_addr(net, addr);
 805
 806	return addr;
 807}
 808
 809void tipc_node_check_dest(struct net *net, u32 addr,
 810			  u8 *peer_id, struct tipc_bearer *b,
 811			  u16 capabilities, u32 signature,
 812			  struct tipc_media_addr *maddr,
 813			  bool *respond, bool *dupl_addr)
 814{
 815	struct tipc_node *n;
 816	struct tipc_link *l;
 817	struct tipc_link_entry *le;
 818	bool addr_match = false;
 819	bool sign_match = false;
 820	bool link_up = false;
 821	bool accept_addr = false;
 822	bool reset = true;
 823	char *if_name;
 824	unsigned long intv;
 
 825
 826	*dupl_addr = false;
 827	*respond = false;
 828
 829	n = tipc_node_create(net, addr, peer_id, capabilities);
 830	if (!n)
 831		return;
 832
 833	tipc_node_write_lock(n);
 834
 835	le = &n->links[b->identity];
 836
 837	/* Prepare to validate requesting node's signature and media address */
 838	l = le->link;
 839	link_up = l && tipc_link_is_up(l);
 840	addr_match = l && !memcmp(&le->maddr, maddr, sizeof(*maddr));
 841	sign_match = (signature == n->signature);
 842
 843	/* These three flags give us eight permutations: */
 844
 845	if (sign_match && addr_match && link_up) {
 846		/* All is fine. Do nothing. */
 847		reset = false;
 848	} else if (sign_match && addr_match && !link_up) {
 849		/* Respond. The link will come up in due time */
 850		*respond = true;
 851	} else if (sign_match && !addr_match && link_up) {
 852		/* Peer has changed i/f address without rebooting.
 853		 * If so, the link will reset soon, and the next
 854		 * discovery will be accepted. So we can ignore it.
 855		 * It may also be an cloned or malicious peer having
 856		 * chosen the same node address and signature as an
 857		 * existing one.
 858		 * Ignore requests until the link goes down, if ever.
 859		 */
 860		*dupl_addr = true;
 861	} else if (sign_match && !addr_match && !link_up) {
 862		/* Peer link has changed i/f address without rebooting.
 863		 * It may also be a cloned or malicious peer; we can't
 864		 * distinguish between the two.
 865		 * The signature is correct, so we must accept.
 866		 */
 867		accept_addr = true;
 868		*respond = true;
 869	} else if (!sign_match && addr_match && link_up) {
 870		/* Peer node rebooted. Two possibilities:
 871		 *  - Delayed re-discovery; this link endpoint has already
 872		 *    reset and re-established contact with the peer, before
 873		 *    receiving a discovery message from that node.
 874		 *    (The peer happened to receive one from this node first).
 875		 *  - The peer came back so fast that our side has not
 876		 *    discovered it yet. Probing from this side will soon
 877		 *    reset the link, since there can be no working link
 878		 *    endpoint at the peer end, and the link will re-establish.
 879		 *  Accept the signature, since it comes from a known peer.
 880		 */
 881		n->signature = signature;
 882	} else if (!sign_match && addr_match && !link_up) {
 883		/*  The peer node has rebooted.
 884		 *  Accept signature, since it is a known peer.
 885		 */
 886		n->signature = signature;
 887		*respond = true;
 888	} else if (!sign_match && !addr_match && link_up) {
 889		/* Peer rebooted with new address, or a new/duplicate peer.
 890		 * Ignore until the link goes down, if ever.
 891		 */
 892		*dupl_addr = true;
 893	} else if (!sign_match && !addr_match && !link_up) {
 894		/* Peer rebooted with new address, or it is a new peer.
 895		 * Accept signature and address.
 896		 */
 897		n->signature = signature;
 898		accept_addr = true;
 899		*respond = true;
 900	}
 901
 902	if (!accept_addr)
 903		goto exit;
 904
 905	/* Now create new link if not already existing */
 906	if (!l) {
 907		if (n->link_cnt == 2)
 908			goto exit;
 909
 910		if_name = strchr(b->name, ':') + 1;
 
 911		if (!tipc_link_create(net, if_name, b->identity, b->tolerance,
 912				      b->net_plane, b->mtu, b->priority,
 913				      b->window, mod(tipc_net(net)->random),
 914				      tipc_own_addr(net), addr, peer_id,
 915				      n->capabilities,
 916				      tipc_bc_sndlink(n->net), n->bc_entry.link,
 917				      &le->inputq,
 918				      &n->bc_entry.namedq, &l)) {
 919			*respond = false;
 920			goto exit;
 921		}
 
 922		tipc_link_reset(l);
 923		tipc_link_fsm_evt(l, LINK_RESET_EVT);
 924		if (n->state == NODE_FAILINGOVER)
 925			tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
 926		le->link = l;
 927		n->link_cnt++;
 928		tipc_node_calculate_timer(n, l);
 929		if (n->link_cnt == 1) {
 930			intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
 931			if (!mod_timer(&n->timer, intv))
 932				tipc_node_get(n);
 933		}
 934	}
 935	memcpy(&le->maddr, maddr, sizeof(*maddr));
 936exit:
 937	tipc_node_write_unlock(n);
 938	if (reset && l && !tipc_link_is_reset(l))
 939		tipc_node_link_down(n, b->identity, false);
 940	tipc_node_put(n);
 941}
 942
 943void tipc_node_delete_links(struct net *net, int bearer_id)
 944{
 945	struct tipc_net *tn = net_generic(net, tipc_net_id);
 946	struct tipc_node *n;
 947
 948	rcu_read_lock();
 949	list_for_each_entry_rcu(n, &tn->node_list, list) {
 950		tipc_node_link_down(n, bearer_id, true);
 951	}
 952	rcu_read_unlock();
 953}
 954
 955static void tipc_node_reset_links(struct tipc_node *n)
 956{
 957	int i;
 958
 959	pr_warn("Resetting all links to %x\n", n->addr);
 960
 
 961	for (i = 0; i < MAX_BEARERS; i++) {
 962		tipc_node_link_down(n, i, false);
 963	}
 964}
 965
 966/* tipc_node_fsm_evt - node finite state machine
 967 * Determines when contact is allowed with peer node
 968 */
 969static void tipc_node_fsm_evt(struct tipc_node *n, int evt)
 970{
 971	int state = n->state;
 972
 973	switch (state) {
 974	case SELF_DOWN_PEER_DOWN:
 975		switch (evt) {
 976		case SELF_ESTABL_CONTACT_EVT:
 977			state = SELF_UP_PEER_COMING;
 978			break;
 979		case PEER_ESTABL_CONTACT_EVT:
 980			state = SELF_COMING_PEER_UP;
 981			break;
 982		case SELF_LOST_CONTACT_EVT:
 983		case PEER_LOST_CONTACT_EVT:
 984			break;
 985		case NODE_SYNCH_END_EVT:
 986		case NODE_SYNCH_BEGIN_EVT:
 987		case NODE_FAILOVER_BEGIN_EVT:
 988		case NODE_FAILOVER_END_EVT:
 989		default:
 990			goto illegal_evt;
 991		}
 992		break;
 993	case SELF_UP_PEER_UP:
 994		switch (evt) {
 995		case SELF_LOST_CONTACT_EVT:
 996			state = SELF_DOWN_PEER_LEAVING;
 997			break;
 998		case PEER_LOST_CONTACT_EVT:
 999			state = SELF_LEAVING_PEER_DOWN;
1000			break;
1001		case NODE_SYNCH_BEGIN_EVT:
1002			state = NODE_SYNCHING;
1003			break;
1004		case NODE_FAILOVER_BEGIN_EVT:
1005			state = NODE_FAILINGOVER;
1006			break;
1007		case SELF_ESTABL_CONTACT_EVT:
1008		case PEER_ESTABL_CONTACT_EVT:
1009		case NODE_SYNCH_END_EVT:
1010		case NODE_FAILOVER_END_EVT:
1011			break;
1012		default:
1013			goto illegal_evt;
1014		}
1015		break;
1016	case SELF_DOWN_PEER_LEAVING:
1017		switch (evt) {
1018		case PEER_LOST_CONTACT_EVT:
1019			state = SELF_DOWN_PEER_DOWN;
1020			break;
1021		case SELF_ESTABL_CONTACT_EVT:
1022		case PEER_ESTABL_CONTACT_EVT:
1023		case SELF_LOST_CONTACT_EVT:
1024			break;
1025		case NODE_SYNCH_END_EVT:
1026		case NODE_SYNCH_BEGIN_EVT:
1027		case NODE_FAILOVER_BEGIN_EVT:
1028		case NODE_FAILOVER_END_EVT:
1029		default:
1030			goto illegal_evt;
1031		}
1032		break;
1033	case SELF_UP_PEER_COMING:
1034		switch (evt) {
1035		case PEER_ESTABL_CONTACT_EVT:
1036			state = SELF_UP_PEER_UP;
1037			break;
1038		case SELF_LOST_CONTACT_EVT:
1039			state = SELF_DOWN_PEER_DOWN;
1040			break;
1041		case SELF_ESTABL_CONTACT_EVT:
1042		case PEER_LOST_CONTACT_EVT:
1043		case NODE_SYNCH_END_EVT:
1044		case NODE_FAILOVER_BEGIN_EVT:
1045			break;
1046		case NODE_SYNCH_BEGIN_EVT:
1047		case NODE_FAILOVER_END_EVT:
1048		default:
1049			goto illegal_evt;
1050		}
1051		break;
1052	case SELF_COMING_PEER_UP:
1053		switch (evt) {
1054		case SELF_ESTABL_CONTACT_EVT:
1055			state = SELF_UP_PEER_UP;
1056			break;
1057		case PEER_LOST_CONTACT_EVT:
1058			state = SELF_DOWN_PEER_DOWN;
1059			break;
1060		case SELF_LOST_CONTACT_EVT:
1061		case PEER_ESTABL_CONTACT_EVT:
1062			break;
1063		case NODE_SYNCH_END_EVT:
1064		case NODE_SYNCH_BEGIN_EVT:
1065		case NODE_FAILOVER_BEGIN_EVT:
1066		case NODE_FAILOVER_END_EVT:
1067		default:
1068			goto illegal_evt;
1069		}
1070		break;
1071	case SELF_LEAVING_PEER_DOWN:
1072		switch (evt) {
1073		case SELF_LOST_CONTACT_EVT:
1074			state = SELF_DOWN_PEER_DOWN;
1075			break;
1076		case SELF_ESTABL_CONTACT_EVT:
1077		case PEER_ESTABL_CONTACT_EVT:
1078		case PEER_LOST_CONTACT_EVT:
1079			break;
1080		case NODE_SYNCH_END_EVT:
1081		case NODE_SYNCH_BEGIN_EVT:
1082		case NODE_FAILOVER_BEGIN_EVT:
1083		case NODE_FAILOVER_END_EVT:
1084		default:
1085			goto illegal_evt;
1086		}
1087		break;
1088	case NODE_FAILINGOVER:
1089		switch (evt) {
1090		case SELF_LOST_CONTACT_EVT:
1091			state = SELF_DOWN_PEER_LEAVING;
1092			break;
1093		case PEER_LOST_CONTACT_EVT:
1094			state = SELF_LEAVING_PEER_DOWN;
1095			break;
1096		case NODE_FAILOVER_END_EVT:
1097			state = SELF_UP_PEER_UP;
1098			break;
1099		case NODE_FAILOVER_BEGIN_EVT:
1100		case SELF_ESTABL_CONTACT_EVT:
1101		case PEER_ESTABL_CONTACT_EVT:
1102			break;
1103		case NODE_SYNCH_BEGIN_EVT:
1104		case NODE_SYNCH_END_EVT:
1105		default:
1106			goto illegal_evt;
1107		}
1108		break;
1109	case NODE_SYNCHING:
1110		switch (evt) {
1111		case SELF_LOST_CONTACT_EVT:
1112			state = SELF_DOWN_PEER_LEAVING;
1113			break;
1114		case PEER_LOST_CONTACT_EVT:
1115			state = SELF_LEAVING_PEER_DOWN;
1116			break;
1117		case NODE_SYNCH_END_EVT:
1118			state = SELF_UP_PEER_UP;
1119			break;
1120		case NODE_FAILOVER_BEGIN_EVT:
1121			state = NODE_FAILINGOVER;
1122			break;
1123		case NODE_SYNCH_BEGIN_EVT:
1124		case SELF_ESTABL_CONTACT_EVT:
1125		case PEER_ESTABL_CONTACT_EVT:
1126			break;
1127		case NODE_FAILOVER_END_EVT:
1128		default:
1129			goto illegal_evt;
1130		}
1131		break;
1132	default:
1133		pr_err("Unknown node fsm state %x\n", state);
1134		break;
1135	}
 
1136	n->state = state;
1137	return;
1138
1139illegal_evt:
1140	pr_err("Illegal node fsm evt %x in state %x\n", evt, state);
 
1141}
1142
1143static void node_lost_contact(struct tipc_node *n,
1144			      struct sk_buff_head *inputq)
1145{
1146	struct tipc_sock_conn *conn, *safe;
1147	struct tipc_link *l;
1148	struct list_head *conns = &n->conn_sks;
1149	struct sk_buff *skb;
1150	uint i;
1151
1152	pr_debug("Lost contact with %x\n", n->addr);
 
 
1153
1154	/* Clean up broadcast state */
1155	tipc_bcast_remove_peer(n->net, n->bc_entry.link);
1156
1157	/* Abort any ongoing link failover */
1158	for (i = 0; i < MAX_BEARERS; i++) {
1159		l = n->links[i].link;
1160		if (l)
1161			tipc_link_fsm_evt(l, LINK_FAILOVER_END_EVT);
1162	}
1163
1164	/* Notify publications from this node */
1165	n->action_flags |= TIPC_NOTIFY_NODE_DOWN;
1166
1167	/* Notify sockets connected to node */
1168	list_for_each_entry_safe(conn, safe, conns, list) {
1169		skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE, TIPC_CONN_MSG,
1170				      SHORT_H_SIZE, 0, tipc_own_addr(n->net),
1171				      conn->peer_node, conn->port,
1172				      conn->peer_port, TIPC_ERR_NO_NODE);
1173		if (likely(skb))
1174			skb_queue_tail(inputq, skb);
1175		list_del(&conn->list);
1176		kfree(conn);
1177	}
1178}
1179
1180/**
1181 * tipc_node_get_linkname - get the name of a link
1182 *
1183 * @bearer_id: id of the bearer
1184 * @node: peer node address
1185 * @linkname: link name output buffer
1186 *
1187 * Returns 0 on success
1188 */
1189int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 addr,
1190			   char *linkname, size_t len)
1191{
1192	struct tipc_link *link;
1193	int err = -EINVAL;
1194	struct tipc_node *node = tipc_node_find(net, addr);
1195
1196	if (!node)
1197		return err;
1198
1199	if (bearer_id >= MAX_BEARERS)
1200		goto exit;
1201
1202	tipc_node_read_lock(node);
1203	link = node->links[bearer_id].link;
1204	if (link) {
1205		strncpy(linkname, tipc_link_name(link), len);
1206		err = 0;
1207	}
1208	tipc_node_read_unlock(node);
1209exit:
1210	tipc_node_put(node);
1211	return err;
1212}
1213
1214/* Caller should hold node lock for the passed node */
1215static int __tipc_nl_add_node(struct tipc_nl_msg *msg, struct tipc_node *node)
1216{
1217	void *hdr;
1218	struct nlattr *attrs;
1219
1220	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1221			  NLM_F_MULTI, TIPC_NL_NODE_GET);
1222	if (!hdr)
1223		return -EMSGSIZE;
1224
1225	attrs = nla_nest_start(msg->skb, TIPC_NLA_NODE);
1226	if (!attrs)
1227		goto msg_full;
1228
1229	if (nla_put_u32(msg->skb, TIPC_NLA_NODE_ADDR, node->addr))
1230		goto attr_msg_full;
1231	if (node_is_up(node))
1232		if (nla_put_flag(msg->skb, TIPC_NLA_NODE_UP))
1233			goto attr_msg_full;
1234
1235	nla_nest_end(msg->skb, attrs);
1236	genlmsg_end(msg->skb, hdr);
1237
1238	return 0;
1239
1240attr_msg_full:
1241	nla_nest_cancel(msg->skb, attrs);
1242msg_full:
1243	genlmsg_cancel(msg->skb, hdr);
1244
1245	return -EMSGSIZE;
1246}
1247
1248/**
1249 * tipc_node_xmit() is the general link level function for message sending
1250 * @net: the applicable net namespace
1251 * @list: chain of buffers containing message
1252 * @dnode: address of destination node
1253 * @selector: a number used for deterministic link selection
1254 * Consumes the buffer chain.
1255 * Returns 0 if success, otherwise: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE,-ENOBUF
1256 */
1257int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
1258		   u32 dnode, int selector)
1259{
1260	struct tipc_link_entry *le = NULL;
1261	struct tipc_node *n;
1262	struct sk_buff_head xmitq;
1263	int bearer_id;
1264	int rc;
1265
1266	if (in_own_node(net, dnode)) {
 
 
1267		tipc_sk_rcv(net, list);
1268		return 0;
1269	}
1270
1271	n = tipc_node_find(net, dnode);
1272	if (unlikely(!n)) {
1273		skb_queue_purge(list);
1274		return -EHOSTUNREACH;
1275	}
1276
1277	tipc_node_read_lock(n);
1278	bearer_id = n->active_links[selector & 1];
1279	if (unlikely(bearer_id == INVALID_BEARER_ID)) {
1280		tipc_node_read_unlock(n);
1281		tipc_node_put(n);
1282		skb_queue_purge(list);
1283		return -EHOSTUNREACH;
1284	}
1285
1286	__skb_queue_head_init(&xmitq);
1287	le = &n->links[bearer_id];
1288	spin_lock_bh(&le->lock);
1289	rc = tipc_link_xmit(le->link, list, &xmitq);
1290	spin_unlock_bh(&le->lock);
1291	tipc_node_read_unlock(n);
1292
1293	if (unlikely(rc == -ENOBUFS))
1294		tipc_node_link_down(n, bearer_id, false);
1295	else
1296		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr);
1297
1298	tipc_node_put(n);
1299
1300	return rc;
1301}
1302
1303/* tipc_node_xmit_skb(): send single buffer to destination
1304 * Buffers sent via this functon are generally TIPC_SYSTEM_IMPORTANCE
1305 * messages, which will not be rejected
1306 * The only exception is datagram messages rerouted after secondary
1307 * lookup, which are rare and safe to dispose of anyway.
1308 */
1309int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode,
1310		       u32 selector)
1311{
1312	struct sk_buff_head head;
1313
1314	skb_queue_head_init(&head);
1315	__skb_queue_tail(&head, skb);
1316	tipc_node_xmit(net, &head, dnode, selector);
1317	return 0;
1318}
1319
1320/* tipc_node_distr_xmit(): send single buffer msgs to individual destinations
1321 * Note: this is only for SYSTEM_IMPORTANCE messages, which cannot be rejected
1322 */
1323int tipc_node_distr_xmit(struct net *net, struct sk_buff_head *xmitq)
1324{
1325	struct sk_buff *skb;
1326	u32 selector, dnode;
1327
1328	while ((skb = __skb_dequeue(xmitq))) {
1329		selector = msg_origport(buf_msg(skb));
1330		dnode = msg_destnode(buf_msg(skb));
1331		tipc_node_xmit_skb(net, skb, dnode, selector);
1332	}
1333	return 0;
1334}
1335
1336void tipc_node_broadcast(struct net *net, struct sk_buff *skb)
1337{
1338	struct sk_buff *txskb;
1339	struct tipc_node *n;
1340	u32 dst;
1341
1342	rcu_read_lock();
1343	list_for_each_entry_rcu(n, tipc_nodes(net), list) {
1344		dst = n->addr;
1345		if (in_own_node(net, dst))
1346			continue;
1347		if (!node_is_up(n))
1348			continue;
1349		txskb = pskb_copy(skb, GFP_ATOMIC);
1350		if (!txskb)
1351			break;
1352		msg_set_destnode(buf_msg(txskb), dst);
1353		tipc_node_xmit_skb(net, txskb, dst, 0);
1354	}
1355	rcu_read_unlock();
1356
1357	kfree_skb(skb);
1358}
1359
1360static void tipc_node_mcast_rcv(struct tipc_node *n)
1361{
1362	struct tipc_bclink_entry *be = &n->bc_entry;
1363
1364	/* 'arrvq' is under inputq2's lock protection */
1365	spin_lock_bh(&be->inputq2.lock);
1366	spin_lock_bh(&be->inputq1.lock);
1367	skb_queue_splice_tail_init(&be->inputq1, &be->arrvq);
1368	spin_unlock_bh(&be->inputq1.lock);
1369	spin_unlock_bh(&be->inputq2.lock);
1370	tipc_sk_mcast_rcv(n->net, &be->arrvq, &be->inputq2);
1371}
1372
1373static void tipc_node_bc_sync_rcv(struct tipc_node *n, struct tipc_msg *hdr,
1374				  int bearer_id, struct sk_buff_head *xmitq)
1375{
1376	struct tipc_link *ucl;
1377	int rc;
1378
1379	rc = tipc_bcast_sync_rcv(n->net, n->bc_entry.link, hdr);
1380
1381	if (rc & TIPC_LINK_DOWN_EVT) {
1382		tipc_node_reset_links(n);
1383		return;
1384	}
1385
1386	if (!(rc & TIPC_LINK_SND_STATE))
1387		return;
1388
1389	/* If probe message, a STATE response will be sent anyway */
1390	if (msg_probe(hdr))
1391		return;
1392
1393	/* Produce a STATE message carrying broadcast NACK */
1394	tipc_node_read_lock(n);
1395	ucl = n->links[bearer_id].link;
1396	if (ucl)
1397		tipc_link_build_state_msg(ucl, xmitq);
1398	tipc_node_read_unlock(n);
1399}
1400
1401/**
1402 * tipc_node_bc_rcv - process TIPC broadcast packet arriving from off-node
1403 * @net: the applicable net namespace
1404 * @skb: TIPC packet
1405 * @bearer_id: id of bearer message arrived on
1406 *
1407 * Invoked with no locks held.
1408 */
1409static void tipc_node_bc_rcv(struct net *net, struct sk_buff *skb, int bearer_id)
1410{
1411	int rc;
1412	struct sk_buff_head xmitq;
1413	struct tipc_bclink_entry *be;
1414	struct tipc_link_entry *le;
1415	struct tipc_msg *hdr = buf_msg(skb);
1416	int usr = msg_user(hdr);
1417	u32 dnode = msg_destnode(hdr);
1418	struct tipc_node *n;
1419
1420	__skb_queue_head_init(&xmitq);
1421
1422	/* If NACK for other node, let rcv link for that node peek into it */
1423	if ((usr == BCAST_PROTOCOL) && (dnode != tipc_own_addr(net)))
1424		n = tipc_node_find(net, dnode);
1425	else
1426		n = tipc_node_find(net, msg_prevnode(hdr));
1427	if (!n) {
1428		kfree_skb(skb);
1429		return;
1430	}
1431	be = &n->bc_entry;
1432	le = &n->links[bearer_id];
1433
1434	rc = tipc_bcast_rcv(net, be->link, skb);
1435
1436	/* Broadcast ACKs are sent on a unicast link */
1437	if (rc & TIPC_LINK_SND_STATE) {
1438		tipc_node_read_lock(n);
1439		tipc_link_build_state_msg(le->link, &xmitq);
1440		tipc_node_read_unlock(n);
1441	}
1442
1443	if (!skb_queue_empty(&xmitq))
1444		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr);
1445
1446	if (!skb_queue_empty(&be->inputq1))
1447		tipc_node_mcast_rcv(n);
1448
 
 
 
 
1449	/* If reassembly or retransmission failure => reset all links to peer */
1450	if (rc & TIPC_LINK_DOWN_EVT)
1451		tipc_node_reset_links(n);
1452
1453	tipc_node_put(n);
1454}
1455
1456/**
1457 * tipc_node_check_state - check and if necessary update node state
1458 * @skb: TIPC packet
1459 * @bearer_id: identity of bearer delivering the packet
1460 * Returns true if state is ok, otherwise consumes buffer and returns false
1461 */
1462static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
1463				  int bearer_id, struct sk_buff_head *xmitq)
1464{
1465	struct tipc_msg *hdr = buf_msg(skb);
1466	int usr = msg_user(hdr);
1467	int mtyp = msg_type(hdr);
1468	u16 oseqno = msg_seqno(hdr);
1469	u16 iseqno = msg_seqno(msg_get_wrapped(hdr));
1470	u16 exp_pkts = msg_msgcnt(hdr);
1471	u16 rcv_nxt, syncpt, dlv_nxt, inputq_len;
1472	int state = n->state;
1473	struct tipc_link *l, *tnl, *pl = NULL;
1474	struct tipc_media_addr *maddr;
1475	int pb_id;
1476
 
 
 
 
1477	l = n->links[bearer_id].link;
1478	if (!l)
1479		return false;
1480	rcv_nxt = tipc_link_rcv_nxt(l);
1481
1482
1483	if (likely((state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL)))
1484		return true;
1485
1486	/* Find parallel link, if any */
1487	for (pb_id = 0; pb_id < MAX_BEARERS; pb_id++) {
1488		if ((pb_id != bearer_id) && n->links[pb_id].link) {
1489			pl = n->links[pb_id].link;
1490			break;
1491		}
1492	}
1493
 
 
 
 
 
 
1494	/* Check and update node accesibility if applicable */
1495	if (state == SELF_UP_PEER_COMING) {
1496		if (!tipc_link_is_up(l))
1497			return true;
1498		if (!msg_peer_link_is_up(hdr))
1499			return true;
1500		tipc_node_fsm_evt(n, PEER_ESTABL_CONTACT_EVT);
1501	}
1502
1503	if (state == SELF_DOWN_PEER_LEAVING) {
1504		if (msg_peer_node_is_up(hdr))
1505			return false;
1506		tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
1507		return true;
1508	}
1509
1510	if (state == SELF_LEAVING_PEER_DOWN)
1511		return false;
1512
1513	/* Ignore duplicate packets */
1514	if ((usr != LINK_PROTOCOL) && less(oseqno, rcv_nxt))
1515		return true;
1516
1517	/* Initiate or update failover mode if applicable */
1518	if ((usr == TUNNEL_PROTOCOL) && (mtyp == FAILOVER_MSG)) {
1519		syncpt = oseqno + exp_pkts - 1;
1520		if (pl && tipc_link_is_up(pl)) {
1521			__tipc_node_link_down(n, &pb_id, xmitq, &maddr);
 
 
1522			tipc_skb_queue_splice_tail_init(tipc_link_inputq(pl),
1523							tipc_link_inputq(l));
1524		}
 
 
 
 
 
 
 
 
 
 
1525		/* If pkts arrive out of order, use lowest calculated syncpt */
1526		if (less(syncpt, n->sync_point))
1527			n->sync_point = syncpt;
1528	}
1529
1530	/* Open parallel link when tunnel link reaches synch point */
1531	if ((n->state == NODE_FAILINGOVER) && tipc_link_is_up(l)) {
1532		if (!more(rcv_nxt, n->sync_point))
1533			return true;
1534		tipc_node_fsm_evt(n, NODE_FAILOVER_END_EVT);
1535		if (pl)
1536			tipc_link_fsm_evt(pl, LINK_FAILOVER_END_EVT);
1537		return true;
1538	}
1539
1540	/* No synching needed if only one link */
1541	if (!pl || !tipc_link_is_up(pl))
1542		return true;
1543
1544	/* Initiate synch mode if applicable */
1545	if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG) && (oseqno == 1)) {
1546		syncpt = iseqno + exp_pkts - 1;
 
 
 
1547		if (!tipc_link_is_up(l))
1548			__tipc_node_link_up(n, bearer_id, xmitq);
1549		if (n->state == SELF_UP_PEER_UP) {
1550			n->sync_point = syncpt;
1551			tipc_link_fsm_evt(l, LINK_SYNCH_BEGIN_EVT);
1552			tipc_node_fsm_evt(n, NODE_SYNCH_BEGIN_EVT);
1553		}
1554	}
1555
1556	/* Open tunnel link when parallel link reaches synch point */
1557	if (n->state == NODE_SYNCHING) {
1558		if (tipc_link_is_synching(l)) {
1559			tnl = l;
1560		} else {
1561			tnl = pl;
1562			pl = l;
1563		}
1564		inputq_len = skb_queue_len(tipc_link_inputq(pl));
1565		dlv_nxt = tipc_link_rcv_nxt(pl) - inputq_len;
1566		if (more(dlv_nxt, n->sync_point)) {
1567			tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
1568			tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
1569			return true;
1570		}
1571		if (l == pl)
1572			return true;
1573		if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG))
1574			return true;
1575		if (usr == LINK_PROTOCOL)
1576			return true;
1577		return false;
1578	}
1579	return true;
1580}
1581
1582/**
1583 * tipc_rcv - process TIPC packets/messages arriving from off-node
1584 * @net: the applicable net namespace
1585 * @skb: TIPC packet
1586 * @bearer: pointer to bearer message arrived on
1587 *
1588 * Invoked with no locks held. Bearer pointer must point to a valid bearer
1589 * structure (i.e. cannot be NULL), but bearer can be inactive.
1590 */
1591void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
1592{
1593	struct sk_buff_head xmitq;
1594	struct tipc_node *n;
1595	struct tipc_msg *hdr;
1596	int bearer_id = b->identity;
1597	struct tipc_link_entry *le;
1598	u32 self = tipc_own_addr(net);
1599	int usr, rc = 0;
1600	u16 bc_ack;
1601
1602	__skb_queue_head_init(&xmitq);
1603
1604	/* Ensure message is well-formed before touching the header */
 
1605	if (unlikely(!tipc_msg_validate(&skb)))
1606		goto discard;
1607	hdr = buf_msg(skb);
1608	usr = msg_user(hdr);
1609	bc_ack = msg_bcast_ack(hdr);
1610
1611	/* Handle arrival of discovery or broadcast packet */
1612	if (unlikely(msg_non_seq(hdr))) {
1613		if (unlikely(usr == LINK_CONFIG))
1614			return tipc_disc_rcv(net, skb, b);
1615		else
1616			return tipc_node_bc_rcv(net, skb, bearer_id);
1617	}
1618
1619	/* Discard unicast link messages destined for another node */
1620	if (unlikely(!msg_short(hdr) && (msg_destnode(hdr) != self)))
1621		goto discard;
1622
1623	/* Locate neighboring node that sent packet */
1624	n = tipc_node_find(net, msg_prevnode(hdr));
1625	if (unlikely(!n))
1626		goto discard;
1627	le = &n->links[bearer_id];
1628
1629	/* Ensure broadcast reception is in synch with peer's send state */
1630	if (unlikely(usr == LINK_PROTOCOL))
1631		tipc_node_bc_sync_rcv(n, hdr, bearer_id, &xmitq);
1632	else if (unlikely(tipc_link_acked(n->bc_entry.link) != bc_ack))
1633		tipc_bcast_ack_rcv(net, n->bc_entry.link, hdr);
1634
1635	/* Receive packet directly if conditions permit */
1636	tipc_node_read_lock(n);
1637	if (likely((n->state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL))) {
1638		spin_lock_bh(&le->lock);
1639		if (le->link) {
1640			rc = tipc_link_rcv(le->link, skb, &xmitq);
1641			skb = NULL;
1642		}
1643		spin_unlock_bh(&le->lock);
1644	}
1645	tipc_node_read_unlock(n);
1646
1647	/* Check/update node state before receiving */
1648	if (unlikely(skb)) {
1649		if (unlikely(skb_linearize(skb)))
1650			goto discard;
1651		tipc_node_write_lock(n);
1652		if (tipc_node_check_state(n, skb, bearer_id, &xmitq)) {
1653			if (le->link) {
1654				rc = tipc_link_rcv(le->link, skb, &xmitq);
1655				skb = NULL;
1656			}
1657		}
1658		tipc_node_write_unlock(n);
1659	}
1660
1661	if (unlikely(rc & TIPC_LINK_UP_EVT))
1662		tipc_node_link_up(n, bearer_id, &xmitq);
1663
1664	if (unlikely(rc & TIPC_LINK_DOWN_EVT))
1665		tipc_node_link_down(n, bearer_id, false);
1666
1667	if (unlikely(!skb_queue_empty(&n->bc_entry.namedq)))
1668		tipc_named_rcv(net, &n->bc_entry.namedq);
1669
1670	if (unlikely(!skb_queue_empty(&n->bc_entry.inputq1)))
1671		tipc_node_mcast_rcv(n);
1672
1673	if (!skb_queue_empty(&le->inputq))
1674		tipc_sk_rcv(net, &le->inputq);
1675
1676	if (!skb_queue_empty(&xmitq))
1677		tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr);
1678
1679	tipc_node_put(n);
1680discard:
1681	kfree_skb(skb);
1682}
1683
1684void tipc_node_apply_tolerance(struct net *net, struct tipc_bearer *b)
 
1685{
1686	struct tipc_net *tn = tipc_net(net);
1687	int bearer_id = b->identity;
1688	struct sk_buff_head xmitq;
1689	struct tipc_link_entry *e;
1690	struct tipc_node *n;
1691
1692	__skb_queue_head_init(&xmitq);
1693
1694	rcu_read_lock();
1695
1696	list_for_each_entry_rcu(n, &tn->node_list, list) {
1697		tipc_node_write_lock(n);
1698		e = &n->links[bearer_id];
1699		if (e->link)
1700			tipc_link_set_tolerance(e->link, b->tolerance, &xmitq);
 
 
 
 
 
1701		tipc_node_write_unlock(n);
1702		tipc_bearer_xmit(net, bearer_id, &xmitq, &e->maddr);
1703	}
1704
1705	rcu_read_unlock();
1706}
1707
1708int tipc_nl_peer_rm(struct sk_buff *skb, struct genl_info *info)
1709{
1710	struct net *net = sock_net(skb->sk);
1711	struct tipc_net *tn = net_generic(net, tipc_net_id);
1712	struct nlattr *attrs[TIPC_NLA_NET_MAX + 1];
1713	struct tipc_node *peer;
1714	u32 addr;
1715	int err;
1716	int i;
1717
1718	/* We identify the peer by its net */
1719	if (!info->attrs[TIPC_NLA_NET])
1720		return -EINVAL;
1721
1722	err = nla_parse_nested(attrs, TIPC_NLA_NET_MAX,
1723			       info->attrs[TIPC_NLA_NET], tipc_nl_net_policy,
1724			       info->extack);
1725	if (err)
1726		return err;
1727
1728	if (!attrs[TIPC_NLA_NET_ADDR])
1729		return -EINVAL;
1730
1731	addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]);
1732
1733	if (in_own_node(net, addr))
1734		return -ENOTSUPP;
1735
1736	spin_lock_bh(&tn->node_list_lock);
1737	peer = tipc_node_find(net, addr);
1738	if (!peer) {
1739		spin_unlock_bh(&tn->node_list_lock);
1740		return -ENXIO;
1741	}
1742
1743	tipc_node_write_lock(peer);
1744	if (peer->state != SELF_DOWN_PEER_DOWN &&
1745	    peer->state != SELF_DOWN_PEER_LEAVING) {
1746		tipc_node_write_unlock(peer);
1747		err = -EBUSY;
1748		goto err_out;
1749	}
1750
1751	for (i = 0; i < MAX_BEARERS; i++) {
1752		struct tipc_link_entry *le = &peer->links[i];
1753
1754		if (le->link) {
1755			kfree(le->link);
1756			le->link = NULL;
1757			peer->link_cnt--;
1758		}
1759	}
1760	tipc_node_write_unlock(peer);
1761	tipc_node_delete(peer);
1762
1763	err = 0;
1764err_out:
1765	tipc_node_put(peer);
1766	spin_unlock_bh(&tn->node_list_lock);
1767
1768	return err;
1769}
1770
1771int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb)
1772{
1773	int err;
1774	struct net *net = sock_net(skb->sk);
1775	struct tipc_net *tn = net_generic(net, tipc_net_id);
1776	int done = cb->args[0];
1777	int last_addr = cb->args[1];
1778	struct tipc_node *node;
1779	struct tipc_nl_msg msg;
1780
1781	if (done)
1782		return 0;
1783
1784	msg.skb = skb;
1785	msg.portid = NETLINK_CB(cb->skb).portid;
1786	msg.seq = cb->nlh->nlmsg_seq;
1787
1788	rcu_read_lock();
1789	if (last_addr) {
1790		node = tipc_node_find(net, last_addr);
1791		if (!node) {
1792			rcu_read_unlock();
1793			/* We never set seq or call nl_dump_check_consistent()
1794			 * this means that setting prev_seq here will cause the
1795			 * consistence check to fail in the netlink callback
1796			 * handler. Resulting in the NLMSG_DONE message having
1797			 * the NLM_F_DUMP_INTR flag set if the node state
1798			 * changed while we released the lock.
1799			 */
1800			cb->prev_seq = 1;
1801			return -EPIPE;
1802		}
1803		tipc_node_put(node);
1804	}
1805
1806	list_for_each_entry_rcu(node, &tn->node_list, list) {
1807		if (last_addr) {
1808			if (node->addr == last_addr)
1809				last_addr = 0;
1810			else
1811				continue;
1812		}
1813
1814		tipc_node_read_lock(node);
1815		err = __tipc_nl_add_node(&msg, node);
1816		if (err) {
1817			last_addr = node->addr;
1818			tipc_node_read_unlock(node);
1819			goto out;
1820		}
1821
1822		tipc_node_read_unlock(node);
1823	}
1824	done = 1;
1825out:
1826	cb->args[0] = done;
1827	cb->args[1] = last_addr;
1828	rcu_read_unlock();
1829
1830	return skb->len;
1831}
1832
1833/* tipc_node_find_by_name - locate owner node of link by link's name
1834 * @net: the applicable net namespace
1835 * @name: pointer to link name string
1836 * @bearer_id: pointer to index in 'node->links' array where the link was found.
1837 *
1838 * Returns pointer to node owning the link, or 0 if no matching link is found.
1839 */
1840static struct tipc_node *tipc_node_find_by_name(struct net *net,
1841						const char *link_name,
1842						unsigned int *bearer_id)
1843{
1844	struct tipc_net *tn = net_generic(net, tipc_net_id);
1845	struct tipc_link *l;
1846	struct tipc_node *n;
1847	struct tipc_node *found_node = NULL;
1848	int i;
1849
1850	*bearer_id = 0;
1851	rcu_read_lock();
1852	list_for_each_entry_rcu(n, &tn->node_list, list) {
1853		tipc_node_read_lock(n);
1854		for (i = 0; i < MAX_BEARERS; i++) {
1855			l = n->links[i].link;
1856			if (l && !strcmp(tipc_link_name(l), link_name)) {
1857				*bearer_id = i;
1858				found_node = n;
1859				break;
1860			}
1861		}
1862		tipc_node_read_unlock(n);
1863		if (found_node)
1864			break;
1865	}
1866	rcu_read_unlock();
1867
1868	return found_node;
1869}
1870
1871int tipc_nl_node_set_link(struct sk_buff *skb, struct genl_info *info)
1872{
1873	int err;
1874	int res = 0;
1875	int bearer_id;
1876	char *name;
1877	struct tipc_link *link;
1878	struct tipc_node *node;
1879	struct sk_buff_head xmitq;
1880	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
1881	struct net *net = sock_net(skb->sk);
1882
1883	__skb_queue_head_init(&xmitq);
1884
1885	if (!info->attrs[TIPC_NLA_LINK])
1886		return -EINVAL;
1887
1888	err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
1889			       info->attrs[TIPC_NLA_LINK],
1890			       tipc_nl_link_policy, info->extack);
1891	if (err)
1892		return err;
1893
1894	if (!attrs[TIPC_NLA_LINK_NAME])
1895		return -EINVAL;
1896
1897	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
1898
1899	if (strcmp(name, tipc_bclink_name) == 0)
1900		return tipc_nl_bc_link_set(net, attrs);
1901
1902	node = tipc_node_find_by_name(net, name, &bearer_id);
1903	if (!node)
1904		return -EINVAL;
1905
1906	tipc_node_read_lock(node);
1907
1908	link = node->links[bearer_id].link;
1909	if (!link) {
1910		res = -EINVAL;
1911		goto out;
1912	}
1913
1914	if (attrs[TIPC_NLA_LINK_PROP]) {
1915		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
1916
1917		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP],
1918					      props);
1919		if (err) {
1920			res = err;
1921			goto out;
1922		}
1923
1924		if (props[TIPC_NLA_PROP_TOL]) {
1925			u32 tol;
1926
1927			tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1928			tipc_link_set_tolerance(link, tol, &xmitq);
1929		}
1930		if (props[TIPC_NLA_PROP_PRIO]) {
1931			u32 prio;
1932
1933			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1934			tipc_link_set_prio(link, prio, &xmitq);
1935		}
1936		if (props[TIPC_NLA_PROP_WIN]) {
1937			u32 win;
1938
1939			win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1940			tipc_link_set_queue_limits(link, win);
1941		}
1942	}
1943
1944out:
1945	tipc_node_read_unlock(node);
1946	tipc_bearer_xmit(net, bearer_id, &xmitq, &node->links[bearer_id].maddr);
1947	return res;
1948}
1949
1950int tipc_nl_node_get_link(struct sk_buff *skb, struct genl_info *info)
1951{
1952	struct net *net = genl_info_net(info);
1953	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
1954	struct tipc_nl_msg msg;
1955	char *name;
1956	int err;
1957
1958	msg.portid = info->snd_portid;
1959	msg.seq = info->snd_seq;
1960
1961	if (!info->attrs[TIPC_NLA_LINK])
1962		return -EINVAL;
1963
1964	err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
1965			       info->attrs[TIPC_NLA_LINK],
1966			       tipc_nl_link_policy, info->extack);
1967	if (err)
1968		return err;
1969
1970	if (!attrs[TIPC_NLA_LINK_NAME])
1971		return -EINVAL;
1972
1973	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
1974
1975	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
1976	if (!msg.skb)
1977		return -ENOMEM;
1978
1979	if (strcmp(name, tipc_bclink_name) == 0) {
1980		err = tipc_nl_add_bc_link(net, &msg);
1981		if (err)
1982			goto err_free;
1983	} else {
1984		int bearer_id;
1985		struct tipc_node *node;
1986		struct tipc_link *link;
1987
1988		node = tipc_node_find_by_name(net, name, &bearer_id);
1989		if (!node) {
1990			err = -EINVAL;
1991			goto err_free;
1992		}
1993
1994		tipc_node_read_lock(node);
1995		link = node->links[bearer_id].link;
1996		if (!link) {
1997			tipc_node_read_unlock(node);
1998			err = -EINVAL;
1999			goto err_free;
2000		}
2001
2002		err = __tipc_nl_add_link(net, &msg, link, 0);
2003		tipc_node_read_unlock(node);
2004		if (err)
2005			goto err_free;
2006	}
2007
2008	return genlmsg_reply(msg.skb, info);
2009
2010err_free:
2011	nlmsg_free(msg.skb);
2012	return err;
2013}
2014
2015int tipc_nl_node_reset_link_stats(struct sk_buff *skb, struct genl_info *info)
2016{
2017	int err;
2018	char *link_name;
2019	unsigned int bearer_id;
2020	struct tipc_link *link;
2021	struct tipc_node *node;
2022	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2023	struct net *net = sock_net(skb->sk);
2024	struct tipc_link_entry *le;
2025
2026	if (!info->attrs[TIPC_NLA_LINK])
2027		return -EINVAL;
2028
2029	err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
2030			       info->attrs[TIPC_NLA_LINK],
2031			       tipc_nl_link_policy, info->extack);
2032	if (err)
2033		return err;
2034
2035	if (!attrs[TIPC_NLA_LINK_NAME])
2036		return -EINVAL;
2037
2038	link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2039
2040	if (strcmp(link_name, tipc_bclink_name) == 0) {
2041		err = tipc_bclink_reset_stats(net);
2042		if (err)
2043			return err;
2044		return 0;
2045	}
2046
2047	node = tipc_node_find_by_name(net, link_name, &bearer_id);
2048	if (!node)
2049		return -EINVAL;
2050
2051	le = &node->links[bearer_id];
2052	tipc_node_read_lock(node);
2053	spin_lock_bh(&le->lock);
2054	link = node->links[bearer_id].link;
2055	if (!link) {
2056		spin_unlock_bh(&le->lock);
2057		tipc_node_read_unlock(node);
2058		return -EINVAL;
2059	}
2060	tipc_link_reset_stats(link);
2061	spin_unlock_bh(&le->lock);
2062	tipc_node_read_unlock(node);
2063	return 0;
2064}
2065
2066/* Caller should hold node lock  */
2067static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
2068				    struct tipc_node *node, u32 *prev_link)
2069{
2070	u32 i;
2071	int err;
2072
2073	for (i = *prev_link; i < MAX_BEARERS; i++) {
2074		*prev_link = i;
2075
2076		if (!node->links[i].link)
2077			continue;
2078
2079		err = __tipc_nl_add_link(net, msg,
2080					 node->links[i].link, NLM_F_MULTI);
2081		if (err)
2082			return err;
2083	}
2084	*prev_link = 0;
2085
2086	return 0;
2087}
2088
2089int tipc_nl_node_dump_link(struct sk_buff *skb, struct netlink_callback *cb)
2090{
2091	struct net *net = sock_net(skb->sk);
2092	struct tipc_net *tn = net_generic(net, tipc_net_id);
2093	struct tipc_node *node;
2094	struct tipc_nl_msg msg;
2095	u32 prev_node = cb->args[0];
2096	u32 prev_link = cb->args[1];
2097	int done = cb->args[2];
2098	int err;
2099
2100	if (done)
2101		return 0;
2102
2103	msg.skb = skb;
2104	msg.portid = NETLINK_CB(cb->skb).portid;
2105	msg.seq = cb->nlh->nlmsg_seq;
2106
2107	rcu_read_lock();
2108	if (prev_node) {
2109		node = tipc_node_find(net, prev_node);
2110		if (!node) {
2111			/* We never set seq or call nl_dump_check_consistent()
2112			 * this means that setting prev_seq here will cause the
2113			 * consistence check to fail in the netlink callback
2114			 * handler. Resulting in the last NLMSG_DONE message
2115			 * having the NLM_F_DUMP_INTR flag set.
2116			 */
2117			cb->prev_seq = 1;
2118			goto out;
2119		}
2120		tipc_node_put(node);
2121
2122		list_for_each_entry_continue_rcu(node, &tn->node_list,
2123						 list) {
2124			tipc_node_read_lock(node);
2125			err = __tipc_nl_add_node_links(net, &msg, node,
2126						       &prev_link);
2127			tipc_node_read_unlock(node);
2128			if (err)
2129				goto out;
2130
2131			prev_node = node->addr;
2132		}
2133	} else {
2134		err = tipc_nl_add_bc_link(net, &msg);
2135		if (err)
2136			goto out;
2137
2138		list_for_each_entry_rcu(node, &tn->node_list, list) {
2139			tipc_node_read_lock(node);
2140			err = __tipc_nl_add_node_links(net, &msg, node,
2141						       &prev_link);
2142			tipc_node_read_unlock(node);
2143			if (err)
2144				goto out;
2145
2146			prev_node = node->addr;
2147		}
2148	}
2149	done = 1;
2150out:
2151	rcu_read_unlock();
2152
2153	cb->args[0] = prev_node;
2154	cb->args[1] = prev_link;
2155	cb->args[2] = done;
2156
2157	return skb->len;
2158}
2159
2160int tipc_nl_node_set_monitor(struct sk_buff *skb, struct genl_info *info)
2161{
2162	struct nlattr *attrs[TIPC_NLA_MON_MAX + 1];
2163	struct net *net = sock_net(skb->sk);
2164	int err;
2165
2166	if (!info->attrs[TIPC_NLA_MON])
2167		return -EINVAL;
2168
2169	err = nla_parse_nested(attrs, TIPC_NLA_MON_MAX,
2170			       info->attrs[TIPC_NLA_MON],
2171			       tipc_nl_monitor_policy, info->extack);
 
2172	if (err)
2173		return err;
2174
2175	if (attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]) {
2176		u32 val;
2177
2178		val = nla_get_u32(attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]);
2179		err = tipc_nl_monitor_set_threshold(net, val);
2180		if (err)
2181			return err;
2182	}
2183
2184	return 0;
2185}
2186
2187static int __tipc_nl_add_monitor_prop(struct net *net, struct tipc_nl_msg *msg)
2188{
2189	struct nlattr *attrs;
2190	void *hdr;
2191	u32 val;
2192
2193	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2194			  0, TIPC_NL_MON_GET);
2195	if (!hdr)
2196		return -EMSGSIZE;
2197
2198	attrs = nla_nest_start(msg->skb, TIPC_NLA_MON);
2199	if (!attrs)
2200		goto msg_full;
2201
2202	val = tipc_nl_monitor_get_threshold(net);
2203
2204	if (nla_put_u32(msg->skb, TIPC_NLA_MON_ACTIVATION_THRESHOLD, val))
2205		goto attr_msg_full;
2206
2207	nla_nest_end(msg->skb, attrs);
2208	genlmsg_end(msg->skb, hdr);
2209
2210	return 0;
2211
2212attr_msg_full:
2213	nla_nest_cancel(msg->skb, attrs);
2214msg_full:
2215	genlmsg_cancel(msg->skb, hdr);
2216
2217	return -EMSGSIZE;
2218}
2219
2220int tipc_nl_node_get_monitor(struct sk_buff *skb, struct genl_info *info)
2221{
2222	struct net *net = sock_net(skb->sk);
2223	struct tipc_nl_msg msg;
2224	int err;
2225
2226	msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2227	if (!msg.skb)
2228		return -ENOMEM;
2229	msg.portid = info->snd_portid;
2230	msg.seq = info->snd_seq;
2231
2232	err = __tipc_nl_add_monitor_prop(net, &msg);
2233	if (err) {
2234		nlmsg_free(msg.skb);
2235		return err;
2236	}
2237
2238	return genlmsg_reply(msg.skb, info);
2239}
2240
2241int tipc_nl_node_dump_monitor(struct sk_buff *skb, struct netlink_callback *cb)
2242{
2243	struct net *net = sock_net(skb->sk);
2244	u32 prev_bearer = cb->args[0];
2245	struct tipc_nl_msg msg;
2246	int bearer_id;
2247	int err;
2248
2249	if (prev_bearer == MAX_BEARERS)
2250		return 0;
2251
2252	msg.skb = skb;
2253	msg.portid = NETLINK_CB(cb->skb).portid;
2254	msg.seq = cb->nlh->nlmsg_seq;
2255
2256	rtnl_lock();
2257	for (bearer_id = prev_bearer; bearer_id < MAX_BEARERS; bearer_id++) {
2258		err = __tipc_nl_add_monitor(net, &msg, bearer_id);
2259		if (err)
2260			break;
2261	}
2262	rtnl_unlock();
2263	cb->args[0] = bearer_id;
2264
2265	return skb->len;
2266}
2267
2268int tipc_nl_node_dump_monitor_peer(struct sk_buff *skb,
2269				   struct netlink_callback *cb)
2270{
2271	struct net *net = sock_net(skb->sk);
2272	u32 prev_node = cb->args[1];
2273	u32 bearer_id = cb->args[2];
2274	int done = cb->args[0];
2275	struct tipc_nl_msg msg;
2276	int err;
2277
2278	if (!prev_node) {
2279		struct nlattr **attrs;
2280		struct nlattr *mon[TIPC_NLA_MON_MAX + 1];
2281
2282		err = tipc_nlmsg_parse(cb->nlh, &attrs);
2283		if (err)
2284			return err;
2285
2286		if (!attrs[TIPC_NLA_MON])
2287			return -EINVAL;
2288
2289		err = nla_parse_nested(mon, TIPC_NLA_MON_MAX,
2290				       attrs[TIPC_NLA_MON],
2291				       tipc_nl_monitor_policy, NULL);
 
2292		if (err)
2293			return err;
2294
2295		if (!mon[TIPC_NLA_MON_REF])
2296			return -EINVAL;
2297
2298		bearer_id = nla_get_u32(mon[TIPC_NLA_MON_REF]);
2299
2300		if (bearer_id >= MAX_BEARERS)
2301			return -EINVAL;
2302	}
2303
2304	if (done)
2305		return 0;
2306
2307	msg.skb = skb;
2308	msg.portid = NETLINK_CB(cb->skb).portid;
2309	msg.seq = cb->nlh->nlmsg_seq;
2310
2311	rtnl_lock();
2312	err = tipc_nl_add_monitor_peer(net, &msg, bearer_id, &prev_node);
2313	if (!err)
2314		done = 1;
2315
2316	rtnl_unlock();
2317	cb->args[0] = done;
2318	cb->args[1] = prev_node;
2319	cb->args[2] = bearer_id;
2320
2321	return skb->len;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2322}