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 "discover.h" 44 #include "netlink.h" 45 46 #define INVALID_NODE_SIG 0x10000 47 48 /* Flags used to take different actions according to flag type 49 * TIPC_NOTIFY_NODE_DOWN: notify node is down 50 * TIPC_NOTIFY_NODE_UP: notify node is up 51 * TIPC_DISTRIBUTE_NAME: publish or withdraw link state name type 52 */ 53 enum { 54 TIPC_NOTIFY_NODE_DOWN = (1 << 3), 55 TIPC_NOTIFY_NODE_UP = (1 << 4), 56 TIPC_NOTIFY_LINK_UP = (1 << 6), 57 TIPC_NOTIFY_LINK_DOWN = (1 << 7) 58 }; 59 60 struct tipc_link_entry { 61 struct tipc_link *link; 62 spinlock_t lock; /* per link */ 63 u32 mtu; 64 struct sk_buff_head inputq; 65 struct tipc_media_addr maddr; 66 }; 67 68 struct tipc_bclink_entry { 69 struct tipc_link *link; 70 struct sk_buff_head inputq1; 71 struct sk_buff_head arrvq; 72 struct sk_buff_head inputq2; 73 struct sk_buff_head namedq; 74 }; 75 76 /** 77 * struct tipc_node - TIPC node structure 78 * @addr: network address of node 79 * @ref: reference counter to node object 80 * @lock: rwlock governing access to structure 81 * @net: the applicable net namespace 82 * @hash: links to adjacent nodes in unsorted hash chain 83 * @inputq: pointer to input queue containing messages for msg event 84 * @namedq: pointer to name table input queue with name table messages 85 * @active_links: bearer ids of active links, used as index into links[] array 86 * @links: array containing references to all links to node 87 * @action_flags: bit mask of different types of node actions 88 * @state: connectivity state vs peer node 89 * @sync_point: sequence number where synch/failover is finished 90 * @list: links to adjacent nodes in sorted list of cluster's nodes 91 * @working_links: number of working links to node (both active and standby) 92 * @link_cnt: number of links to node 93 * @capabilities: bitmap, indicating peer node's functional capabilities 94 * @signature: node instance identifier 95 * @link_id: local and remote bearer ids of changing link, if any 96 * @publ_list: list of publications 97 * @rcu: rcu struct for tipc_node 98 */ 99 struct tipc_node { 100 u32 addr; 101 struct kref kref; 102 rwlock_t lock; 103 struct net *net; 104 struct hlist_node hash; 105 int active_links[2]; 106 struct tipc_link_entry links[MAX_BEARERS]; 107 struct tipc_bclink_entry bc_entry; 108 int action_flags; 109 struct list_head list; 110 int state; 111 u16 sync_point; 112 int link_cnt; 113 u16 working_links; 114 u16 capabilities; 115 u32 signature; 116 u32 link_id; 117 struct list_head publ_list; 118 struct list_head conn_sks; 119 unsigned long keepalive_intv; 120 struct timer_list timer; 121 struct rcu_head rcu; 122 }; 123 124 /* Node FSM states and events: 125 */ 126 enum { 127 SELF_DOWN_PEER_DOWN = 0xdd, 128 SELF_UP_PEER_UP = 0xaa, 129 SELF_DOWN_PEER_LEAVING = 0xd1, 130 SELF_UP_PEER_COMING = 0xac, 131 SELF_COMING_PEER_UP = 0xca, 132 SELF_LEAVING_PEER_DOWN = 0x1d, 133 NODE_FAILINGOVER = 0xf0, 134 NODE_SYNCHING = 0xcc 135 }; 136 137 enum { 138 SELF_ESTABL_CONTACT_EVT = 0xece, 139 SELF_LOST_CONTACT_EVT = 0x1ce, 140 PEER_ESTABL_CONTACT_EVT = 0x9ece, 141 PEER_LOST_CONTACT_EVT = 0x91ce, 142 NODE_FAILOVER_BEGIN_EVT = 0xfbe, 143 NODE_FAILOVER_END_EVT = 0xfee, 144 NODE_SYNCH_BEGIN_EVT = 0xcbe, 145 NODE_SYNCH_END_EVT = 0xcee 146 }; 147 148 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id, 149 struct sk_buff_head *xmitq, 150 struct tipc_media_addr **maddr); 151 static void tipc_node_link_down(struct tipc_node *n, int bearer_id, 152 bool delete); 153 static void node_lost_contact(struct tipc_node *n, struct sk_buff_head *inputq); 154 static void tipc_node_delete(struct tipc_node *node); 155 static void tipc_node_timeout(unsigned long data); 156 static void tipc_node_fsm_evt(struct tipc_node *n, int evt); 157 static struct tipc_node *tipc_node_find(struct net *net, u32 addr); 158 static void tipc_node_put(struct tipc_node *node); 159 static bool tipc_node_is_up(struct tipc_node *n); 160 161 struct tipc_sock_conn { 162 u32 port; 163 u32 peer_port; 164 u32 peer_node; 165 struct list_head list; 166 }; 167 168 static struct tipc_link *node_active_link(struct tipc_node *n, int sel) 169 { 170 int bearer_id = n->active_links[sel & 1]; 171 172 if (unlikely(bearer_id == INVALID_BEARER_ID)) 173 return NULL; 174 175 return n->links[bearer_id].link; 176 } 177 178 int tipc_node_get_mtu(struct net *net, u32 addr, u32 sel) 179 { 180 struct tipc_node *n; 181 int bearer_id; 182 unsigned int mtu = MAX_MSG_SIZE; 183 184 n = tipc_node_find(net, addr); 185 if (unlikely(!n)) 186 return mtu; 187 188 bearer_id = n->active_links[sel & 1]; 189 if (likely(bearer_id != INVALID_BEARER_ID)) 190 mtu = n->links[bearer_id].mtu; 191 tipc_node_put(n); 192 return mtu; 193 } 194 195 u16 tipc_node_get_capabilities(struct net *net, u32 addr) 196 { 197 struct tipc_node *n; 198 u16 caps; 199 200 n = tipc_node_find(net, addr); 201 if (unlikely(!n)) 202 return TIPC_NODE_CAPABILITIES; 203 caps = n->capabilities; 204 tipc_node_put(n); 205 return caps; 206 } 207 208 /* 209 * A trivial power-of-two bitmask technique is used for speed, since this 210 * operation is done for every incoming TIPC packet. The number of hash table 211 * entries has been chosen so that no hash chain exceeds 8 nodes and will 212 * usually be much smaller (typically only a single node). 213 */ 214 static unsigned int tipc_hashfn(u32 addr) 215 { 216 return addr & (NODE_HTABLE_SIZE - 1); 217 } 218 219 static void tipc_node_kref_release(struct kref *kref) 220 { 221 struct tipc_node *n = container_of(kref, struct tipc_node, kref); 222 223 kfree(n->bc_entry.link); 224 kfree_rcu(n, rcu); 225 } 226 227 static void tipc_node_put(struct tipc_node *node) 228 { 229 kref_put(&node->kref, tipc_node_kref_release); 230 } 231 232 static void tipc_node_get(struct tipc_node *node) 233 { 234 kref_get(&node->kref); 235 } 236 237 /* 238 * tipc_node_find - locate specified node object, if it exists 239 */ 240 static struct tipc_node *tipc_node_find(struct net *net, u32 addr) 241 { 242 struct tipc_net *tn = tipc_net(net); 243 struct tipc_node *node; 244 unsigned int thash = tipc_hashfn(addr); 245 246 if (unlikely(!in_own_cluster_exact(net, addr))) 247 return NULL; 248 249 rcu_read_lock(); 250 hlist_for_each_entry_rcu(node, &tn->node_htable[thash], hash) { 251 if (node->addr != addr) 252 continue; 253 if (!kref_get_unless_zero(&node->kref)) 254 node = NULL; 255 break; 256 } 257 rcu_read_unlock(); 258 return node; 259 } 260 261 static void tipc_node_read_lock(struct tipc_node *n) 262 { 263 read_lock_bh(&n->lock); 264 } 265 266 static void tipc_node_read_unlock(struct tipc_node *n) 267 { 268 read_unlock_bh(&n->lock); 269 } 270 271 static void tipc_node_write_lock(struct tipc_node *n) 272 { 273 write_lock_bh(&n->lock); 274 } 275 276 static void tipc_node_write_unlock(struct tipc_node *n) 277 { 278 struct net *net = n->net; 279 u32 addr = 0; 280 u32 flags = n->action_flags; 281 u32 link_id = 0; 282 struct list_head *publ_list; 283 284 if (likely(!flags)) { 285 write_unlock_bh(&n->lock); 286 return; 287 } 288 289 addr = n->addr; 290 link_id = n->link_id; 291 publ_list = &n->publ_list; 292 293 n->action_flags &= ~(TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP | 294 TIPC_NOTIFY_LINK_DOWN | TIPC_NOTIFY_LINK_UP); 295 296 write_unlock_bh(&n->lock); 297 298 if (flags & TIPC_NOTIFY_NODE_DOWN) 299 tipc_publ_notify(net, publ_list, addr); 300 301 if (flags & TIPC_NOTIFY_NODE_UP) 302 tipc_named_node_up(net, addr); 303 304 if (flags & TIPC_NOTIFY_LINK_UP) 305 tipc_nametbl_publish(net, TIPC_LINK_STATE, addr, addr, 306 TIPC_NODE_SCOPE, link_id, addr); 307 308 if (flags & TIPC_NOTIFY_LINK_DOWN) 309 tipc_nametbl_withdraw(net, TIPC_LINK_STATE, addr, 310 link_id, addr); 311 } 312 313 struct tipc_node *tipc_node_create(struct net *net, u32 addr, u16 capabilities) 314 { 315 struct tipc_net *tn = net_generic(net, tipc_net_id); 316 struct tipc_node *n, *temp_node; 317 int i; 318 319 spin_lock_bh(&tn->node_list_lock); 320 n = tipc_node_find(net, addr); 321 if (n) { 322 /* Same node may come back with new capabilities */ 323 n->capabilities = capabilities; 324 goto exit; 325 } 326 n = kzalloc(sizeof(*n), GFP_ATOMIC); 327 if (!n) { 328 pr_warn("Node creation failed, no memory\n"); 329 goto exit; 330 } 331 n->addr = addr; 332 n->net = net; 333 n->capabilities = capabilities; 334 kref_init(&n->kref); 335 rwlock_init(&n->lock); 336 INIT_HLIST_NODE(&n->hash); 337 INIT_LIST_HEAD(&n->list); 338 INIT_LIST_HEAD(&n->publ_list); 339 INIT_LIST_HEAD(&n->conn_sks); 340 skb_queue_head_init(&n->bc_entry.namedq); 341 skb_queue_head_init(&n->bc_entry.inputq1); 342 __skb_queue_head_init(&n->bc_entry.arrvq); 343 skb_queue_head_init(&n->bc_entry.inputq2); 344 for (i = 0; i < MAX_BEARERS; i++) 345 spin_lock_init(&n->links[i].lock); 346 n->state = SELF_DOWN_PEER_LEAVING; 347 n->signature = INVALID_NODE_SIG; 348 n->active_links[0] = INVALID_BEARER_ID; 349 n->active_links[1] = INVALID_BEARER_ID; 350 if (!tipc_link_bc_create(net, tipc_own_addr(net), n->addr, 351 U16_MAX, 352 tipc_link_window(tipc_bc_sndlink(net)), 353 n->capabilities, 354 &n->bc_entry.inputq1, 355 &n->bc_entry.namedq, 356 tipc_bc_sndlink(net), 357 &n->bc_entry.link)) { 358 pr_warn("Broadcast rcv link creation failed, no memory\n"); 359 kfree(n); 360 n = NULL; 361 goto exit; 362 } 363 tipc_node_get(n); 364 setup_timer(&n->timer, tipc_node_timeout, (unsigned long)n); 365 n->keepalive_intv = U32_MAX; 366 hlist_add_head_rcu(&n->hash, &tn->node_htable[tipc_hashfn(addr)]); 367 list_for_each_entry_rcu(temp_node, &tn->node_list, list) { 368 if (n->addr < temp_node->addr) 369 break; 370 } 371 list_add_tail_rcu(&n->list, &temp_node->list); 372 exit: 373 spin_unlock_bh(&tn->node_list_lock); 374 return n; 375 } 376 377 static void tipc_node_calculate_timer(struct tipc_node *n, struct tipc_link *l) 378 { 379 unsigned long tol = tipc_link_tolerance(l); 380 unsigned long intv = ((tol / 4) > 500) ? 500 : tol / 4; 381 unsigned long keepalive_intv = msecs_to_jiffies(intv); 382 383 /* Link with lowest tolerance determines timer interval */ 384 if (keepalive_intv < n->keepalive_intv) 385 n->keepalive_intv = keepalive_intv; 386 387 /* Ensure link's abort limit corresponds to current interval */ 388 tipc_link_set_abort_limit(l, tol / jiffies_to_msecs(n->keepalive_intv)); 389 } 390 391 static void tipc_node_delete(struct tipc_node *node) 392 { 393 list_del_rcu(&node->list); 394 hlist_del_rcu(&node->hash); 395 tipc_node_put(node); 396 397 del_timer_sync(&node->timer); 398 tipc_node_put(node); 399 } 400 401 void tipc_node_stop(struct net *net) 402 { 403 struct tipc_net *tn = tipc_net(net); 404 struct tipc_node *node, *t_node; 405 406 spin_lock_bh(&tn->node_list_lock); 407 list_for_each_entry_safe(node, t_node, &tn->node_list, list) 408 tipc_node_delete(node); 409 spin_unlock_bh(&tn->node_list_lock); 410 } 411 412 void tipc_node_subscribe(struct net *net, struct list_head *subscr, u32 addr) 413 { 414 struct tipc_node *n; 415 416 if (in_own_node(net, addr)) 417 return; 418 419 n = tipc_node_find(net, addr); 420 if (!n) { 421 pr_warn("Node subscribe rejected, unknown node 0x%x\n", addr); 422 return; 423 } 424 tipc_node_write_lock(n); 425 list_add_tail(subscr, &n->publ_list); 426 tipc_node_write_unlock(n); 427 tipc_node_put(n); 428 } 429 430 void tipc_node_unsubscribe(struct net *net, struct list_head *subscr, u32 addr) 431 { 432 struct tipc_node *n; 433 434 if (in_own_node(net, addr)) 435 return; 436 437 n = tipc_node_find(net, addr); 438 if (!n) { 439 pr_warn("Node unsubscribe rejected, unknown node 0x%x\n", addr); 440 return; 441 } 442 tipc_node_write_lock(n); 443 list_del_init(subscr); 444 tipc_node_write_unlock(n); 445 tipc_node_put(n); 446 } 447 448 int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port) 449 { 450 struct tipc_node *node; 451 struct tipc_sock_conn *conn; 452 int err = 0; 453 454 if (in_own_node(net, dnode)) 455 return 0; 456 457 node = tipc_node_find(net, dnode); 458 if (!node) { 459 pr_warn("Connecting sock to node 0x%x failed\n", dnode); 460 return -EHOSTUNREACH; 461 } 462 conn = kmalloc(sizeof(*conn), GFP_ATOMIC); 463 if (!conn) { 464 err = -EHOSTUNREACH; 465 goto exit; 466 } 467 conn->peer_node = dnode; 468 conn->port = port; 469 conn->peer_port = peer_port; 470 471 tipc_node_write_lock(node); 472 list_add_tail(&conn->list, &node->conn_sks); 473 tipc_node_write_unlock(node); 474 exit: 475 tipc_node_put(node); 476 return err; 477 } 478 479 void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port) 480 { 481 struct tipc_node *node; 482 struct tipc_sock_conn *conn, *safe; 483 484 if (in_own_node(net, dnode)) 485 return; 486 487 node = tipc_node_find(net, dnode); 488 if (!node) 489 return; 490 491 tipc_node_write_lock(node); 492 list_for_each_entry_safe(conn, safe, &node->conn_sks, list) { 493 if (port != conn->port) 494 continue; 495 list_del(&conn->list); 496 kfree(conn); 497 } 498 tipc_node_write_unlock(node); 499 tipc_node_put(node); 500 } 501 502 /* tipc_node_timeout - handle expiration of node timer 503 */ 504 static void tipc_node_timeout(unsigned long data) 505 { 506 struct tipc_node *n = (struct tipc_node *)data; 507 struct tipc_link_entry *le; 508 struct sk_buff_head xmitq; 509 int bearer_id; 510 int rc = 0; 511 512 __skb_queue_head_init(&xmitq); 513 514 for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) { 515 tipc_node_read_lock(n); 516 le = &n->links[bearer_id]; 517 spin_lock_bh(&le->lock); 518 if (le->link) { 519 /* Link tolerance may change asynchronously: */ 520 tipc_node_calculate_timer(n, le->link); 521 rc = tipc_link_timeout(le->link, &xmitq); 522 } 523 spin_unlock_bh(&le->lock); 524 tipc_node_read_unlock(n); 525 tipc_bearer_xmit(n->net, bearer_id, &xmitq, &le->maddr); 526 if (rc & TIPC_LINK_DOWN_EVT) 527 tipc_node_link_down(n, bearer_id, false); 528 } 529 mod_timer(&n->timer, jiffies + n->keepalive_intv); 530 } 531 532 /** 533 * __tipc_node_link_up - handle addition of link 534 * Node lock must be held by caller 535 * Link becomes active (alone or shared) or standby, depending on its priority. 536 */ 537 static void __tipc_node_link_up(struct tipc_node *n, int bearer_id, 538 struct sk_buff_head *xmitq) 539 { 540 int *slot0 = &n->active_links[0]; 541 int *slot1 = &n->active_links[1]; 542 struct tipc_link *ol = node_active_link(n, 0); 543 struct tipc_link *nl = n->links[bearer_id].link; 544 545 if (!nl || tipc_link_is_up(nl)) 546 return; 547 548 tipc_link_fsm_evt(nl, LINK_ESTABLISH_EVT); 549 if (!tipc_link_is_up(nl)) 550 return; 551 552 n->working_links++; 553 n->action_flags |= TIPC_NOTIFY_LINK_UP; 554 n->link_id = tipc_link_id(nl); 555 556 /* Leave room for tunnel header when returning 'mtu' to users: */ 557 n->links[bearer_id].mtu = tipc_link_mtu(nl) - INT_H_SIZE; 558 559 tipc_bearer_add_dest(n->net, bearer_id, n->addr); 560 tipc_bcast_inc_bearer_dst_cnt(n->net, bearer_id); 561 562 pr_debug("Established link <%s> on network plane %c\n", 563 tipc_link_name(nl), tipc_link_plane(nl)); 564 565 /* Ensure that a STATE message goes first */ 566 tipc_link_build_state_msg(nl, xmitq); 567 568 /* First link? => give it both slots */ 569 if (!ol) { 570 *slot0 = bearer_id; 571 *slot1 = bearer_id; 572 tipc_node_fsm_evt(n, SELF_ESTABL_CONTACT_EVT); 573 n->action_flags |= TIPC_NOTIFY_NODE_UP; 574 tipc_link_set_active(nl, true); 575 tipc_bcast_add_peer(n->net, nl, xmitq); 576 return; 577 } 578 579 /* Second link => redistribute slots */ 580 if (tipc_link_prio(nl) > tipc_link_prio(ol)) { 581 pr_debug("Old link <%s> becomes standby\n", tipc_link_name(ol)); 582 *slot0 = bearer_id; 583 *slot1 = bearer_id; 584 tipc_link_set_active(nl, true); 585 tipc_link_set_active(ol, false); 586 } else if (tipc_link_prio(nl) == tipc_link_prio(ol)) { 587 tipc_link_set_active(nl, true); 588 *slot1 = bearer_id; 589 } else { 590 pr_debug("New link <%s> is standby\n", tipc_link_name(nl)); 591 } 592 593 /* Prepare synchronization with first link */ 594 tipc_link_tnl_prepare(ol, nl, SYNCH_MSG, xmitq); 595 } 596 597 /** 598 * tipc_node_link_up - handle addition of link 599 * 600 * Link becomes active (alone or shared) or standby, depending on its priority. 601 */ 602 static void tipc_node_link_up(struct tipc_node *n, int bearer_id, 603 struct sk_buff_head *xmitq) 604 { 605 struct tipc_media_addr *maddr; 606 607 tipc_node_write_lock(n); 608 __tipc_node_link_up(n, bearer_id, xmitq); 609 maddr = &n->links[bearer_id].maddr; 610 tipc_bearer_xmit(n->net, bearer_id, xmitq, maddr); 611 tipc_node_write_unlock(n); 612 } 613 614 /** 615 * __tipc_node_link_down - handle loss of link 616 */ 617 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id, 618 struct sk_buff_head *xmitq, 619 struct tipc_media_addr **maddr) 620 { 621 struct tipc_link_entry *le = &n->links[*bearer_id]; 622 int *slot0 = &n->active_links[0]; 623 int *slot1 = &n->active_links[1]; 624 int i, highest = 0, prio; 625 struct tipc_link *l, *_l, *tnl; 626 627 l = n->links[*bearer_id].link; 628 if (!l || tipc_link_is_reset(l)) 629 return; 630 631 n->working_links--; 632 n->action_flags |= TIPC_NOTIFY_LINK_DOWN; 633 n->link_id = tipc_link_id(l); 634 635 tipc_bearer_remove_dest(n->net, *bearer_id, n->addr); 636 637 pr_debug("Lost link <%s> on network plane %c\n", 638 tipc_link_name(l), tipc_link_plane(l)); 639 640 /* Select new active link if any available */ 641 *slot0 = INVALID_BEARER_ID; 642 *slot1 = INVALID_BEARER_ID; 643 for (i = 0; i < MAX_BEARERS; i++) { 644 _l = n->links[i].link; 645 if (!_l || !tipc_link_is_up(_l)) 646 continue; 647 if (_l == l) 648 continue; 649 prio = tipc_link_prio(_l); 650 if (prio < highest) 651 continue; 652 if (prio > highest) { 653 highest = prio; 654 *slot0 = i; 655 *slot1 = i; 656 continue; 657 } 658 *slot1 = i; 659 } 660 661 if (!tipc_node_is_up(n)) { 662 if (tipc_link_peer_is_down(l)) 663 tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT); 664 tipc_node_fsm_evt(n, SELF_LOST_CONTACT_EVT); 665 tipc_link_fsm_evt(l, LINK_RESET_EVT); 666 tipc_link_reset(l); 667 tipc_link_build_reset_msg(l, xmitq); 668 *maddr = &n->links[*bearer_id].maddr; 669 node_lost_contact(n, &le->inputq); 670 tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id); 671 return; 672 } 673 tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id); 674 675 /* There is still a working link => initiate failover */ 676 *bearer_id = n->active_links[0]; 677 tnl = n->links[*bearer_id].link; 678 tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT); 679 tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT); 680 n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1); 681 tipc_link_tnl_prepare(l, tnl, FAILOVER_MSG, xmitq); 682 tipc_link_reset(l); 683 tipc_link_fsm_evt(l, LINK_RESET_EVT); 684 tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT); 685 tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT); 686 *maddr = &n->links[*bearer_id].maddr; 687 } 688 689 static void tipc_node_link_down(struct tipc_node *n, int bearer_id, bool delete) 690 { 691 struct tipc_link_entry *le = &n->links[bearer_id]; 692 struct tipc_link *l = le->link; 693 struct tipc_media_addr *maddr; 694 struct sk_buff_head xmitq; 695 696 if (!l) 697 return; 698 699 __skb_queue_head_init(&xmitq); 700 701 tipc_node_write_lock(n); 702 if (!tipc_link_is_establishing(l)) { 703 __tipc_node_link_down(n, &bearer_id, &xmitq, &maddr); 704 if (delete) { 705 kfree(l); 706 le->link = NULL; 707 n->link_cnt--; 708 } 709 } else { 710 /* Defuse pending tipc_node_link_up() */ 711 tipc_link_fsm_evt(l, LINK_RESET_EVT); 712 } 713 tipc_node_write_unlock(n); 714 tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr); 715 tipc_sk_rcv(n->net, &le->inputq); 716 } 717 718 static bool tipc_node_is_up(struct tipc_node *n) 719 { 720 return n->active_links[0] != INVALID_BEARER_ID; 721 } 722 723 void tipc_node_check_dest(struct net *net, u32 onode, 724 struct tipc_bearer *b, 725 u16 capabilities, u32 signature, 726 struct tipc_media_addr *maddr, 727 bool *respond, bool *dupl_addr) 728 { 729 struct tipc_node *n; 730 struct tipc_link *l; 731 struct tipc_link_entry *le; 732 bool addr_match = false; 733 bool sign_match = false; 734 bool link_up = false; 735 bool accept_addr = false; 736 bool reset = true; 737 char *if_name; 738 739 *dupl_addr = false; 740 *respond = false; 741 742 n = tipc_node_create(net, onode, capabilities); 743 if (!n) 744 return; 745 746 tipc_node_write_lock(n); 747 748 le = &n->links[b->identity]; 749 750 /* Prepare to validate requesting node's signature and media address */ 751 l = le->link; 752 link_up = l && tipc_link_is_up(l); 753 addr_match = l && !memcmp(&le->maddr, maddr, sizeof(*maddr)); 754 sign_match = (signature == n->signature); 755 756 /* These three flags give us eight permutations: */ 757 758 if (sign_match && addr_match && link_up) { 759 /* All is fine. Do nothing. */ 760 reset = false; 761 } else if (sign_match && addr_match && !link_up) { 762 /* Respond. The link will come up in due time */ 763 *respond = true; 764 } else if (sign_match && !addr_match && link_up) { 765 /* Peer has changed i/f address without rebooting. 766 * If so, the link will reset soon, and the next 767 * discovery will be accepted. So we can ignore it. 768 * It may also be an cloned or malicious peer having 769 * chosen the same node address and signature as an 770 * existing one. 771 * Ignore requests until the link goes down, if ever. 772 */ 773 *dupl_addr = true; 774 } else if (sign_match && !addr_match && !link_up) { 775 /* Peer link has changed i/f address without rebooting. 776 * It may also be a cloned or malicious peer; we can't 777 * distinguish between the two. 778 * The signature is correct, so we must accept. 779 */ 780 accept_addr = true; 781 *respond = true; 782 } else if (!sign_match && addr_match && link_up) { 783 /* Peer node rebooted. Two possibilities: 784 * - Delayed re-discovery; this link endpoint has already 785 * reset and re-established contact with the peer, before 786 * receiving a discovery message from that node. 787 * (The peer happened to receive one from this node first). 788 * - The peer came back so fast that our side has not 789 * discovered it yet. Probing from this side will soon 790 * reset the link, since there can be no working link 791 * endpoint at the peer end, and the link will re-establish. 792 * Accept the signature, since it comes from a known peer. 793 */ 794 n->signature = signature; 795 } else if (!sign_match && addr_match && !link_up) { 796 /* The peer node has rebooted. 797 * Accept signature, since it is a known peer. 798 */ 799 n->signature = signature; 800 *respond = true; 801 } else if (!sign_match && !addr_match && link_up) { 802 /* Peer rebooted with new address, or a new/duplicate peer. 803 * Ignore until the link goes down, if ever. 804 */ 805 *dupl_addr = true; 806 } else if (!sign_match && !addr_match && !link_up) { 807 /* Peer rebooted with new address, or it is a new peer. 808 * Accept signature and address. 809 */ 810 n->signature = signature; 811 accept_addr = true; 812 *respond = true; 813 } 814 815 if (!accept_addr) 816 goto exit; 817 818 /* Now create new link if not already existing */ 819 if (!l) { 820 if (n->link_cnt == 2) { 821 pr_warn("Cannot establish 3rd link to %x\n", n->addr); 822 goto exit; 823 } 824 if_name = strchr(b->name, ':') + 1; 825 if (!tipc_link_create(net, if_name, b->identity, b->tolerance, 826 b->net_plane, b->mtu, b->priority, 827 b->window, mod(tipc_net(net)->random), 828 tipc_own_addr(net), onode, 829 n->capabilities, 830 tipc_bc_sndlink(n->net), n->bc_entry.link, 831 &le->inputq, 832 &n->bc_entry.namedq, &l)) { 833 *respond = false; 834 goto exit; 835 } 836 tipc_link_reset(l); 837 tipc_link_fsm_evt(l, LINK_RESET_EVT); 838 if (n->state == NODE_FAILINGOVER) 839 tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT); 840 le->link = l; 841 n->link_cnt++; 842 tipc_node_calculate_timer(n, l); 843 if (n->link_cnt == 1) 844 if (!mod_timer(&n->timer, jiffies + n->keepalive_intv)) 845 tipc_node_get(n); 846 } 847 memcpy(&le->maddr, maddr, sizeof(*maddr)); 848 exit: 849 tipc_node_write_unlock(n); 850 if (reset && l && !tipc_link_is_reset(l)) 851 tipc_node_link_down(n, b->identity, false); 852 tipc_node_put(n); 853 } 854 855 void tipc_node_delete_links(struct net *net, int bearer_id) 856 { 857 struct tipc_net *tn = net_generic(net, tipc_net_id); 858 struct tipc_node *n; 859 860 rcu_read_lock(); 861 list_for_each_entry_rcu(n, &tn->node_list, list) { 862 tipc_node_link_down(n, bearer_id, true); 863 } 864 rcu_read_unlock(); 865 } 866 867 static void tipc_node_reset_links(struct tipc_node *n) 868 { 869 char addr_string[16]; 870 int i; 871 872 pr_warn("Resetting all links to %s\n", 873 tipc_addr_string_fill(addr_string, n->addr)); 874 875 for (i = 0; i < MAX_BEARERS; i++) { 876 tipc_node_link_down(n, i, false); 877 } 878 } 879 880 /* tipc_node_fsm_evt - node finite state machine 881 * Determines when contact is allowed with peer node 882 */ 883 static void tipc_node_fsm_evt(struct tipc_node *n, int evt) 884 { 885 int state = n->state; 886 887 switch (state) { 888 case SELF_DOWN_PEER_DOWN: 889 switch (evt) { 890 case SELF_ESTABL_CONTACT_EVT: 891 state = SELF_UP_PEER_COMING; 892 break; 893 case PEER_ESTABL_CONTACT_EVT: 894 state = SELF_COMING_PEER_UP; 895 break; 896 case SELF_LOST_CONTACT_EVT: 897 case PEER_LOST_CONTACT_EVT: 898 break; 899 case NODE_SYNCH_END_EVT: 900 case NODE_SYNCH_BEGIN_EVT: 901 case NODE_FAILOVER_BEGIN_EVT: 902 case NODE_FAILOVER_END_EVT: 903 default: 904 goto illegal_evt; 905 } 906 break; 907 case SELF_UP_PEER_UP: 908 switch (evt) { 909 case SELF_LOST_CONTACT_EVT: 910 state = SELF_DOWN_PEER_LEAVING; 911 break; 912 case PEER_LOST_CONTACT_EVT: 913 state = SELF_LEAVING_PEER_DOWN; 914 break; 915 case NODE_SYNCH_BEGIN_EVT: 916 state = NODE_SYNCHING; 917 break; 918 case NODE_FAILOVER_BEGIN_EVT: 919 state = NODE_FAILINGOVER; 920 break; 921 case SELF_ESTABL_CONTACT_EVT: 922 case PEER_ESTABL_CONTACT_EVT: 923 case NODE_SYNCH_END_EVT: 924 case NODE_FAILOVER_END_EVT: 925 break; 926 default: 927 goto illegal_evt; 928 } 929 break; 930 case SELF_DOWN_PEER_LEAVING: 931 switch (evt) { 932 case PEER_LOST_CONTACT_EVT: 933 state = SELF_DOWN_PEER_DOWN; 934 break; 935 case SELF_ESTABL_CONTACT_EVT: 936 case PEER_ESTABL_CONTACT_EVT: 937 case SELF_LOST_CONTACT_EVT: 938 break; 939 case NODE_SYNCH_END_EVT: 940 case NODE_SYNCH_BEGIN_EVT: 941 case NODE_FAILOVER_BEGIN_EVT: 942 case NODE_FAILOVER_END_EVT: 943 default: 944 goto illegal_evt; 945 } 946 break; 947 case SELF_UP_PEER_COMING: 948 switch (evt) { 949 case PEER_ESTABL_CONTACT_EVT: 950 state = SELF_UP_PEER_UP; 951 break; 952 case SELF_LOST_CONTACT_EVT: 953 state = SELF_DOWN_PEER_LEAVING; 954 break; 955 case SELF_ESTABL_CONTACT_EVT: 956 case PEER_LOST_CONTACT_EVT: 957 case NODE_SYNCH_END_EVT: 958 case NODE_FAILOVER_BEGIN_EVT: 959 break; 960 case NODE_SYNCH_BEGIN_EVT: 961 case NODE_FAILOVER_END_EVT: 962 default: 963 goto illegal_evt; 964 } 965 break; 966 case SELF_COMING_PEER_UP: 967 switch (evt) { 968 case SELF_ESTABL_CONTACT_EVT: 969 state = SELF_UP_PEER_UP; 970 break; 971 case PEER_LOST_CONTACT_EVT: 972 state = SELF_LEAVING_PEER_DOWN; 973 break; 974 case SELF_LOST_CONTACT_EVT: 975 case PEER_ESTABL_CONTACT_EVT: 976 break; 977 case NODE_SYNCH_END_EVT: 978 case NODE_SYNCH_BEGIN_EVT: 979 case NODE_FAILOVER_BEGIN_EVT: 980 case NODE_FAILOVER_END_EVT: 981 default: 982 goto illegal_evt; 983 } 984 break; 985 case SELF_LEAVING_PEER_DOWN: 986 switch (evt) { 987 case SELF_LOST_CONTACT_EVT: 988 state = SELF_DOWN_PEER_DOWN; 989 break; 990 case SELF_ESTABL_CONTACT_EVT: 991 case PEER_ESTABL_CONTACT_EVT: 992 case PEER_LOST_CONTACT_EVT: 993 break; 994 case NODE_SYNCH_END_EVT: 995 case NODE_SYNCH_BEGIN_EVT: 996 case NODE_FAILOVER_BEGIN_EVT: 997 case NODE_FAILOVER_END_EVT: 998 default: 999 goto illegal_evt; 1000 } 1001 break; 1002 case NODE_FAILINGOVER: 1003 switch (evt) { 1004 case SELF_LOST_CONTACT_EVT: 1005 state = SELF_DOWN_PEER_LEAVING; 1006 break; 1007 case PEER_LOST_CONTACT_EVT: 1008 state = SELF_LEAVING_PEER_DOWN; 1009 break; 1010 case NODE_FAILOVER_END_EVT: 1011 state = SELF_UP_PEER_UP; 1012 break; 1013 case NODE_FAILOVER_BEGIN_EVT: 1014 case SELF_ESTABL_CONTACT_EVT: 1015 case PEER_ESTABL_CONTACT_EVT: 1016 break; 1017 case NODE_SYNCH_BEGIN_EVT: 1018 case NODE_SYNCH_END_EVT: 1019 default: 1020 goto illegal_evt; 1021 } 1022 break; 1023 case NODE_SYNCHING: 1024 switch (evt) { 1025 case SELF_LOST_CONTACT_EVT: 1026 state = SELF_DOWN_PEER_LEAVING; 1027 break; 1028 case PEER_LOST_CONTACT_EVT: 1029 state = SELF_LEAVING_PEER_DOWN; 1030 break; 1031 case NODE_SYNCH_END_EVT: 1032 state = SELF_UP_PEER_UP; 1033 break; 1034 case NODE_FAILOVER_BEGIN_EVT: 1035 state = NODE_FAILINGOVER; 1036 break; 1037 case NODE_SYNCH_BEGIN_EVT: 1038 case SELF_ESTABL_CONTACT_EVT: 1039 case PEER_ESTABL_CONTACT_EVT: 1040 break; 1041 case NODE_FAILOVER_END_EVT: 1042 default: 1043 goto illegal_evt; 1044 } 1045 break; 1046 default: 1047 pr_err("Unknown node fsm state %x\n", state); 1048 break; 1049 } 1050 n->state = state; 1051 return; 1052 1053 illegal_evt: 1054 pr_err("Illegal node fsm evt %x in state %x\n", evt, state); 1055 } 1056 1057 static void node_lost_contact(struct tipc_node *n, 1058 struct sk_buff_head *inputq) 1059 { 1060 char addr_string[16]; 1061 struct tipc_sock_conn *conn, *safe; 1062 struct tipc_link *l; 1063 struct list_head *conns = &n->conn_sks; 1064 struct sk_buff *skb; 1065 uint i; 1066 1067 pr_debug("Lost contact with %s\n", 1068 tipc_addr_string_fill(addr_string, n->addr)); 1069 1070 /* Clean up broadcast state */ 1071 tipc_bcast_remove_peer(n->net, n->bc_entry.link); 1072 1073 /* Abort any ongoing link failover */ 1074 for (i = 0; i < MAX_BEARERS; i++) { 1075 l = n->links[i].link; 1076 if (l) 1077 tipc_link_fsm_evt(l, LINK_FAILOVER_END_EVT); 1078 } 1079 1080 /* Notify publications from this node */ 1081 n->action_flags |= TIPC_NOTIFY_NODE_DOWN; 1082 1083 /* Notify sockets connected to node */ 1084 list_for_each_entry_safe(conn, safe, conns, list) { 1085 skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE, TIPC_CONN_MSG, 1086 SHORT_H_SIZE, 0, tipc_own_addr(n->net), 1087 conn->peer_node, conn->port, 1088 conn->peer_port, TIPC_ERR_NO_NODE); 1089 if (likely(skb)) 1090 skb_queue_tail(inputq, skb); 1091 list_del(&conn->list); 1092 kfree(conn); 1093 } 1094 } 1095 1096 /** 1097 * tipc_node_get_linkname - get the name of a link 1098 * 1099 * @bearer_id: id of the bearer 1100 * @node: peer node address 1101 * @linkname: link name output buffer 1102 * 1103 * Returns 0 on success 1104 */ 1105 int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 addr, 1106 char *linkname, size_t len) 1107 { 1108 struct tipc_link *link; 1109 int err = -EINVAL; 1110 struct tipc_node *node = tipc_node_find(net, addr); 1111 1112 if (!node) 1113 return err; 1114 1115 if (bearer_id >= MAX_BEARERS) 1116 goto exit; 1117 1118 tipc_node_read_lock(node); 1119 link = node->links[bearer_id].link; 1120 if (link) { 1121 strncpy(linkname, tipc_link_name(link), len); 1122 err = 0; 1123 } 1124 exit: 1125 tipc_node_read_unlock(node); 1126 tipc_node_put(node); 1127 return err; 1128 } 1129 1130 /* Caller should hold node lock for the passed node */ 1131 static int __tipc_nl_add_node(struct tipc_nl_msg *msg, struct tipc_node *node) 1132 { 1133 void *hdr; 1134 struct nlattr *attrs; 1135 1136 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family, 1137 NLM_F_MULTI, TIPC_NL_NODE_GET); 1138 if (!hdr) 1139 return -EMSGSIZE; 1140 1141 attrs = nla_nest_start(msg->skb, TIPC_NLA_NODE); 1142 if (!attrs) 1143 goto msg_full; 1144 1145 if (nla_put_u32(msg->skb, TIPC_NLA_NODE_ADDR, node->addr)) 1146 goto attr_msg_full; 1147 if (tipc_node_is_up(node)) 1148 if (nla_put_flag(msg->skb, TIPC_NLA_NODE_UP)) 1149 goto attr_msg_full; 1150 1151 nla_nest_end(msg->skb, attrs); 1152 genlmsg_end(msg->skb, hdr); 1153 1154 return 0; 1155 1156 attr_msg_full: 1157 nla_nest_cancel(msg->skb, attrs); 1158 msg_full: 1159 genlmsg_cancel(msg->skb, hdr); 1160 1161 return -EMSGSIZE; 1162 } 1163 1164 /** 1165 * tipc_node_xmit() is the general link level function for message sending 1166 * @net: the applicable net namespace 1167 * @list: chain of buffers containing message 1168 * @dnode: address of destination node 1169 * @selector: a number used for deterministic link selection 1170 * Consumes the buffer chain, except when returning -ELINKCONG 1171 * Returns 0 if success, otherwise: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE,-ENOBUF 1172 */ 1173 int tipc_node_xmit(struct net *net, struct sk_buff_head *list, 1174 u32 dnode, int selector) 1175 { 1176 struct tipc_link_entry *le = NULL; 1177 struct tipc_node *n; 1178 struct sk_buff_head xmitq; 1179 int bearer_id; 1180 int rc; 1181 1182 if (in_own_node(net, dnode)) { 1183 tipc_sk_rcv(net, list); 1184 return 0; 1185 } 1186 1187 n = tipc_node_find(net, dnode); 1188 if (unlikely(!n)) { 1189 skb_queue_purge(list); 1190 return -EHOSTUNREACH; 1191 } 1192 1193 tipc_node_read_lock(n); 1194 bearer_id = n->active_links[selector & 1]; 1195 if (unlikely(bearer_id == INVALID_BEARER_ID)) { 1196 tipc_node_read_unlock(n); 1197 tipc_node_put(n); 1198 skb_queue_purge(list); 1199 return -EHOSTUNREACH; 1200 } 1201 1202 __skb_queue_head_init(&xmitq); 1203 le = &n->links[bearer_id]; 1204 spin_lock_bh(&le->lock); 1205 rc = tipc_link_xmit(le->link, list, &xmitq); 1206 spin_unlock_bh(&le->lock); 1207 tipc_node_read_unlock(n); 1208 1209 if (likely(rc == 0)) 1210 tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr); 1211 else if (rc == -ENOBUFS) 1212 tipc_node_link_down(n, bearer_id, false); 1213 1214 tipc_node_put(n); 1215 1216 return rc; 1217 } 1218 1219 /* tipc_node_xmit_skb(): send single buffer to destination 1220 * Buffers sent via this functon are generally TIPC_SYSTEM_IMPORTANCE 1221 * messages, which will not be rejected 1222 * The only exception is datagram messages rerouted after secondary 1223 * lookup, which are rare and safe to dispose of anyway. 1224 * TODO: Return real return value, and let callers use 1225 * tipc_wait_for_sendpkt() where applicable 1226 */ 1227 int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode, 1228 u32 selector) 1229 { 1230 struct sk_buff_head head; 1231 int rc; 1232 1233 skb_queue_head_init(&head); 1234 __skb_queue_tail(&head, skb); 1235 rc = tipc_node_xmit(net, &head, dnode, selector); 1236 if (rc == -ELINKCONG) 1237 kfree_skb(skb); 1238 return 0; 1239 } 1240 1241 void tipc_node_broadcast(struct net *net, struct sk_buff *skb) 1242 { 1243 struct sk_buff *txskb; 1244 struct tipc_node *n; 1245 u32 dst; 1246 1247 rcu_read_lock(); 1248 list_for_each_entry_rcu(n, tipc_nodes(net), list) { 1249 dst = n->addr; 1250 if (in_own_node(net, dst)) 1251 continue; 1252 if (!tipc_node_is_up(n)) 1253 continue; 1254 txskb = pskb_copy(skb, GFP_ATOMIC); 1255 if (!txskb) 1256 break; 1257 msg_set_destnode(buf_msg(txskb), dst); 1258 tipc_node_xmit_skb(net, txskb, dst, 0); 1259 } 1260 rcu_read_unlock(); 1261 1262 kfree_skb(skb); 1263 } 1264 1265 /** 1266 * tipc_node_bc_rcv - process TIPC broadcast packet arriving from off-node 1267 * @net: the applicable net namespace 1268 * @skb: TIPC packet 1269 * @bearer_id: id of bearer message arrived on 1270 * 1271 * Invoked with no locks held. 1272 */ 1273 static void tipc_node_bc_rcv(struct net *net, struct sk_buff *skb, int bearer_id) 1274 { 1275 int rc; 1276 struct sk_buff_head xmitq; 1277 struct tipc_bclink_entry *be; 1278 struct tipc_link_entry *le; 1279 struct tipc_msg *hdr = buf_msg(skb); 1280 int usr = msg_user(hdr); 1281 u32 dnode = msg_destnode(hdr); 1282 struct tipc_node *n; 1283 1284 __skb_queue_head_init(&xmitq); 1285 1286 /* If NACK for other node, let rcv link for that node peek into it */ 1287 if ((usr == BCAST_PROTOCOL) && (dnode != tipc_own_addr(net))) 1288 n = tipc_node_find(net, dnode); 1289 else 1290 n = tipc_node_find(net, msg_prevnode(hdr)); 1291 if (!n) { 1292 kfree_skb(skb); 1293 return; 1294 } 1295 be = &n->bc_entry; 1296 le = &n->links[bearer_id]; 1297 1298 rc = tipc_bcast_rcv(net, be->link, skb); 1299 1300 /* Broadcast ACKs are sent on a unicast link */ 1301 if (rc & TIPC_LINK_SND_BC_ACK) { 1302 tipc_node_read_lock(n); 1303 tipc_link_build_state_msg(le->link, &xmitq); 1304 tipc_node_read_unlock(n); 1305 } 1306 1307 if (!skb_queue_empty(&xmitq)) 1308 tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr); 1309 1310 /* Deliver. 'arrvq' is under inputq2's lock protection */ 1311 if (!skb_queue_empty(&be->inputq1)) { 1312 spin_lock_bh(&be->inputq2.lock); 1313 spin_lock_bh(&be->inputq1.lock); 1314 skb_queue_splice_tail_init(&be->inputq1, &be->arrvq); 1315 spin_unlock_bh(&be->inputq1.lock); 1316 spin_unlock_bh(&be->inputq2.lock); 1317 tipc_sk_mcast_rcv(net, &be->arrvq, &be->inputq2); 1318 } 1319 1320 if (rc & TIPC_LINK_DOWN_EVT) { 1321 /* Reception reassembly failure => reset all links to peer */ 1322 if (!tipc_link_is_up(be->link)) 1323 tipc_node_reset_links(n); 1324 1325 /* Retransmission failure => reset all links to all peers */ 1326 if (!tipc_link_is_up(tipc_bc_sndlink(net))) 1327 tipc_bearer_reset_all(net); 1328 } 1329 1330 tipc_node_put(n); 1331 } 1332 1333 /** 1334 * tipc_node_check_state - check and if necessary update node state 1335 * @skb: TIPC packet 1336 * @bearer_id: identity of bearer delivering the packet 1337 * Returns true if state is ok, otherwise consumes buffer and returns false 1338 */ 1339 static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb, 1340 int bearer_id, struct sk_buff_head *xmitq) 1341 { 1342 struct tipc_msg *hdr = buf_msg(skb); 1343 int usr = msg_user(hdr); 1344 int mtyp = msg_type(hdr); 1345 u16 oseqno = msg_seqno(hdr); 1346 u16 iseqno = msg_seqno(msg_get_wrapped(hdr)); 1347 u16 exp_pkts = msg_msgcnt(hdr); 1348 u16 rcv_nxt, syncpt, dlv_nxt, inputq_len; 1349 int state = n->state; 1350 struct tipc_link *l, *tnl, *pl = NULL; 1351 struct tipc_media_addr *maddr; 1352 int pb_id; 1353 1354 l = n->links[bearer_id].link; 1355 if (!l) 1356 return false; 1357 rcv_nxt = tipc_link_rcv_nxt(l); 1358 1359 1360 if (likely((state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL))) 1361 return true; 1362 1363 /* Find parallel link, if any */ 1364 for (pb_id = 0; pb_id < MAX_BEARERS; pb_id++) { 1365 if ((pb_id != bearer_id) && n->links[pb_id].link) { 1366 pl = n->links[pb_id].link; 1367 break; 1368 } 1369 } 1370 1371 /* Check and update node accesibility if applicable */ 1372 if (state == SELF_UP_PEER_COMING) { 1373 if (!tipc_link_is_up(l)) 1374 return true; 1375 if (!msg_peer_link_is_up(hdr)) 1376 return true; 1377 tipc_node_fsm_evt(n, PEER_ESTABL_CONTACT_EVT); 1378 } 1379 1380 if (state == SELF_DOWN_PEER_LEAVING) { 1381 if (msg_peer_node_is_up(hdr)) 1382 return false; 1383 tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT); 1384 return true; 1385 } 1386 1387 if (state == SELF_LEAVING_PEER_DOWN) 1388 return false; 1389 1390 /* Ignore duplicate packets */ 1391 if ((usr != LINK_PROTOCOL) && less(oseqno, rcv_nxt)) 1392 return true; 1393 1394 /* Initiate or update failover mode if applicable */ 1395 if ((usr == TUNNEL_PROTOCOL) && (mtyp == FAILOVER_MSG)) { 1396 syncpt = oseqno + exp_pkts - 1; 1397 if (pl && tipc_link_is_up(pl)) { 1398 __tipc_node_link_down(n, &pb_id, xmitq, &maddr); 1399 tipc_skb_queue_splice_tail_init(tipc_link_inputq(pl), 1400 tipc_link_inputq(l)); 1401 } 1402 /* If pkts arrive out of order, use lowest calculated syncpt */ 1403 if (less(syncpt, n->sync_point)) 1404 n->sync_point = syncpt; 1405 } 1406 1407 /* Open parallel link when tunnel link reaches synch point */ 1408 if ((n->state == NODE_FAILINGOVER) && tipc_link_is_up(l)) { 1409 if (!more(rcv_nxt, n->sync_point)) 1410 return true; 1411 tipc_node_fsm_evt(n, NODE_FAILOVER_END_EVT); 1412 if (pl) 1413 tipc_link_fsm_evt(pl, LINK_FAILOVER_END_EVT); 1414 return true; 1415 } 1416 1417 /* No synching needed if only one link */ 1418 if (!pl || !tipc_link_is_up(pl)) 1419 return true; 1420 1421 /* Initiate synch mode if applicable */ 1422 if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG) && (oseqno == 1)) { 1423 syncpt = iseqno + exp_pkts - 1; 1424 if (!tipc_link_is_up(l)) { 1425 tipc_link_fsm_evt(l, LINK_ESTABLISH_EVT); 1426 __tipc_node_link_up(n, bearer_id, xmitq); 1427 } 1428 if (n->state == SELF_UP_PEER_UP) { 1429 n->sync_point = syncpt; 1430 tipc_link_fsm_evt(l, LINK_SYNCH_BEGIN_EVT); 1431 tipc_node_fsm_evt(n, NODE_SYNCH_BEGIN_EVT); 1432 } 1433 } 1434 1435 /* Open tunnel link when parallel link reaches synch point */ 1436 if (n->state == NODE_SYNCHING) { 1437 if (tipc_link_is_synching(l)) { 1438 tnl = l; 1439 } else { 1440 tnl = pl; 1441 pl = l; 1442 } 1443 inputq_len = skb_queue_len(tipc_link_inputq(pl)); 1444 dlv_nxt = tipc_link_rcv_nxt(pl) - inputq_len; 1445 if (more(dlv_nxt, n->sync_point)) { 1446 tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT); 1447 tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT); 1448 return true; 1449 } 1450 if (l == pl) 1451 return true; 1452 if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG)) 1453 return true; 1454 if (usr == LINK_PROTOCOL) 1455 return true; 1456 return false; 1457 } 1458 return true; 1459 } 1460 1461 /** 1462 * tipc_rcv - process TIPC packets/messages arriving from off-node 1463 * @net: the applicable net namespace 1464 * @skb: TIPC packet 1465 * @bearer: pointer to bearer message arrived on 1466 * 1467 * Invoked with no locks held. Bearer pointer must point to a valid bearer 1468 * structure (i.e. cannot be NULL), but bearer can be inactive. 1469 */ 1470 void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b) 1471 { 1472 struct sk_buff_head xmitq; 1473 struct tipc_node *n; 1474 struct tipc_msg *hdr = buf_msg(skb); 1475 int usr = msg_user(hdr); 1476 int bearer_id = b->identity; 1477 struct tipc_link_entry *le; 1478 u16 bc_ack = msg_bcast_ack(hdr); 1479 u32 self = tipc_own_addr(net); 1480 int rc = 0; 1481 1482 __skb_queue_head_init(&xmitq); 1483 1484 /* Ensure message is well-formed */ 1485 if (unlikely(!tipc_msg_validate(skb))) 1486 goto discard; 1487 1488 /* Handle arrival of discovery or broadcast packet */ 1489 if (unlikely(msg_non_seq(hdr))) { 1490 if (unlikely(usr == LINK_CONFIG)) 1491 return tipc_disc_rcv(net, skb, b); 1492 else 1493 return tipc_node_bc_rcv(net, skb, bearer_id); 1494 } 1495 1496 /* Discard unicast link messages destined for another node */ 1497 if (unlikely(!msg_short(hdr) && (msg_destnode(hdr) != self))) 1498 goto discard; 1499 1500 /* Locate neighboring node that sent packet */ 1501 n = tipc_node_find(net, msg_prevnode(hdr)); 1502 if (unlikely(!n)) 1503 goto discard; 1504 le = &n->links[bearer_id]; 1505 1506 /* Ensure broadcast reception is in synch with peer's send state */ 1507 if (unlikely(usr == LINK_PROTOCOL)) 1508 tipc_bcast_sync_rcv(net, n->bc_entry.link, hdr); 1509 else if (unlikely(tipc_link_acked(n->bc_entry.link) != bc_ack)) 1510 tipc_bcast_ack_rcv(net, n->bc_entry.link, bc_ack); 1511 1512 /* Receive packet directly if conditions permit */ 1513 tipc_node_read_lock(n); 1514 if (likely((n->state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL))) { 1515 spin_lock_bh(&le->lock); 1516 if (le->link) { 1517 rc = tipc_link_rcv(le->link, skb, &xmitq); 1518 skb = NULL; 1519 } 1520 spin_unlock_bh(&le->lock); 1521 } 1522 tipc_node_read_unlock(n); 1523 1524 /* Check/update node state before receiving */ 1525 if (unlikely(skb)) { 1526 tipc_node_write_lock(n); 1527 if (tipc_node_check_state(n, skb, bearer_id, &xmitq)) { 1528 if (le->link) { 1529 rc = tipc_link_rcv(le->link, skb, &xmitq); 1530 skb = NULL; 1531 } 1532 } 1533 tipc_node_write_unlock(n); 1534 } 1535 1536 if (unlikely(rc & TIPC_LINK_UP_EVT)) 1537 tipc_node_link_up(n, bearer_id, &xmitq); 1538 1539 if (unlikely(rc & TIPC_LINK_DOWN_EVT)) 1540 tipc_node_link_down(n, bearer_id, false); 1541 1542 if (unlikely(!skb_queue_empty(&n->bc_entry.namedq))) 1543 tipc_named_rcv(net, &n->bc_entry.namedq); 1544 1545 if (!skb_queue_empty(&le->inputq)) 1546 tipc_sk_rcv(net, &le->inputq); 1547 1548 if (!skb_queue_empty(&xmitq)) 1549 tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr); 1550 1551 tipc_node_put(n); 1552 discard: 1553 kfree_skb(skb); 1554 } 1555 1556 int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb) 1557 { 1558 int err; 1559 struct net *net = sock_net(skb->sk); 1560 struct tipc_net *tn = net_generic(net, tipc_net_id); 1561 int done = cb->args[0]; 1562 int last_addr = cb->args[1]; 1563 struct tipc_node *node; 1564 struct tipc_nl_msg msg; 1565 1566 if (done) 1567 return 0; 1568 1569 msg.skb = skb; 1570 msg.portid = NETLINK_CB(cb->skb).portid; 1571 msg.seq = cb->nlh->nlmsg_seq; 1572 1573 rcu_read_lock(); 1574 if (last_addr) { 1575 node = tipc_node_find(net, last_addr); 1576 if (!node) { 1577 rcu_read_unlock(); 1578 /* We never set seq or call nl_dump_check_consistent() 1579 * this means that setting prev_seq here will cause the 1580 * consistence check to fail in the netlink callback 1581 * handler. Resulting in the NLMSG_DONE message having 1582 * the NLM_F_DUMP_INTR flag set if the node state 1583 * changed while we released the lock. 1584 */ 1585 cb->prev_seq = 1; 1586 return -EPIPE; 1587 } 1588 tipc_node_put(node); 1589 } 1590 1591 list_for_each_entry_rcu(node, &tn->node_list, list) { 1592 if (last_addr) { 1593 if (node->addr == last_addr) 1594 last_addr = 0; 1595 else 1596 continue; 1597 } 1598 1599 tipc_node_read_lock(node); 1600 err = __tipc_nl_add_node(&msg, node); 1601 if (err) { 1602 last_addr = node->addr; 1603 tipc_node_read_unlock(node); 1604 goto out; 1605 } 1606 1607 tipc_node_read_unlock(node); 1608 } 1609 done = 1; 1610 out: 1611 cb->args[0] = done; 1612 cb->args[1] = last_addr; 1613 rcu_read_unlock(); 1614 1615 return skb->len; 1616 } 1617 1618 /* tipc_node_find_by_name - locate owner node of link by link's name 1619 * @net: the applicable net namespace 1620 * @name: pointer to link name string 1621 * @bearer_id: pointer to index in 'node->links' array where the link was found. 1622 * 1623 * Returns pointer to node owning the link, or 0 if no matching link is found. 1624 */ 1625 static struct tipc_node *tipc_node_find_by_name(struct net *net, 1626 const char *link_name, 1627 unsigned int *bearer_id) 1628 { 1629 struct tipc_net *tn = net_generic(net, tipc_net_id); 1630 struct tipc_link *l; 1631 struct tipc_node *n; 1632 struct tipc_node *found_node = NULL; 1633 int i; 1634 1635 *bearer_id = 0; 1636 rcu_read_lock(); 1637 list_for_each_entry_rcu(n, &tn->node_list, list) { 1638 tipc_node_read_lock(n); 1639 for (i = 0; i < MAX_BEARERS; i++) { 1640 l = n->links[i].link; 1641 if (l && !strcmp(tipc_link_name(l), link_name)) { 1642 *bearer_id = i; 1643 found_node = n; 1644 break; 1645 } 1646 } 1647 tipc_node_read_unlock(n); 1648 if (found_node) 1649 break; 1650 } 1651 rcu_read_unlock(); 1652 1653 return found_node; 1654 } 1655 1656 int tipc_nl_node_set_link(struct sk_buff *skb, struct genl_info *info) 1657 { 1658 int err; 1659 int res = 0; 1660 int bearer_id; 1661 char *name; 1662 struct tipc_link *link; 1663 struct tipc_node *node; 1664 struct sk_buff_head xmitq; 1665 struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1]; 1666 struct net *net = sock_net(skb->sk); 1667 1668 __skb_queue_head_init(&xmitq); 1669 1670 if (!info->attrs[TIPC_NLA_LINK]) 1671 return -EINVAL; 1672 1673 err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX, 1674 info->attrs[TIPC_NLA_LINK], 1675 tipc_nl_link_policy); 1676 if (err) 1677 return err; 1678 1679 if (!attrs[TIPC_NLA_LINK_NAME]) 1680 return -EINVAL; 1681 1682 name = nla_data(attrs[TIPC_NLA_LINK_NAME]); 1683 1684 if (strcmp(name, tipc_bclink_name) == 0) 1685 return tipc_nl_bc_link_set(net, attrs); 1686 1687 node = tipc_node_find_by_name(net, name, &bearer_id); 1688 if (!node) 1689 return -EINVAL; 1690 1691 tipc_node_read_lock(node); 1692 1693 link = node->links[bearer_id].link; 1694 if (!link) { 1695 res = -EINVAL; 1696 goto out; 1697 } 1698 1699 if (attrs[TIPC_NLA_LINK_PROP]) { 1700 struct nlattr *props[TIPC_NLA_PROP_MAX + 1]; 1701 1702 err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP], 1703 props); 1704 if (err) { 1705 res = err; 1706 goto out; 1707 } 1708 1709 if (props[TIPC_NLA_PROP_TOL]) { 1710 u32 tol; 1711 1712 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]); 1713 tipc_link_set_tolerance(link, tol, &xmitq); 1714 } 1715 if (props[TIPC_NLA_PROP_PRIO]) { 1716 u32 prio; 1717 1718 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]); 1719 tipc_link_set_prio(link, prio, &xmitq); 1720 } 1721 if (props[TIPC_NLA_PROP_WIN]) { 1722 u32 win; 1723 1724 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]); 1725 tipc_link_set_queue_limits(link, win); 1726 } 1727 } 1728 1729 out: 1730 tipc_node_read_unlock(node); 1731 tipc_bearer_xmit(net, bearer_id, &xmitq, &node->links[bearer_id].maddr); 1732 return res; 1733 } 1734 1735 int tipc_nl_node_get_link(struct sk_buff *skb, struct genl_info *info) 1736 { 1737 struct net *net = genl_info_net(info); 1738 struct tipc_nl_msg msg; 1739 char *name; 1740 int err; 1741 1742 msg.portid = info->snd_portid; 1743 msg.seq = info->snd_seq; 1744 1745 if (!info->attrs[TIPC_NLA_LINK_NAME]) 1746 return -EINVAL; 1747 name = nla_data(info->attrs[TIPC_NLA_LINK_NAME]); 1748 1749 msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); 1750 if (!msg.skb) 1751 return -ENOMEM; 1752 1753 if (strcmp(name, tipc_bclink_name) == 0) { 1754 err = tipc_nl_add_bc_link(net, &msg); 1755 if (err) { 1756 nlmsg_free(msg.skb); 1757 return err; 1758 } 1759 } else { 1760 int bearer_id; 1761 struct tipc_node *node; 1762 struct tipc_link *link; 1763 1764 node = tipc_node_find_by_name(net, name, &bearer_id); 1765 if (!node) 1766 return -EINVAL; 1767 1768 tipc_node_read_lock(node); 1769 link = node->links[bearer_id].link; 1770 if (!link) { 1771 tipc_node_read_unlock(node); 1772 nlmsg_free(msg.skb); 1773 return -EINVAL; 1774 } 1775 1776 err = __tipc_nl_add_link(net, &msg, link, 0); 1777 tipc_node_read_unlock(node); 1778 if (err) { 1779 nlmsg_free(msg.skb); 1780 return err; 1781 } 1782 } 1783 1784 return genlmsg_reply(msg.skb, info); 1785 } 1786 1787 int tipc_nl_node_reset_link_stats(struct sk_buff *skb, struct genl_info *info) 1788 { 1789 int err; 1790 char *link_name; 1791 unsigned int bearer_id; 1792 struct tipc_link *link; 1793 struct tipc_node *node; 1794 struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1]; 1795 struct net *net = sock_net(skb->sk); 1796 struct tipc_link_entry *le; 1797 1798 if (!info->attrs[TIPC_NLA_LINK]) 1799 return -EINVAL; 1800 1801 err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX, 1802 info->attrs[TIPC_NLA_LINK], 1803 tipc_nl_link_policy); 1804 if (err) 1805 return err; 1806 1807 if (!attrs[TIPC_NLA_LINK_NAME]) 1808 return -EINVAL; 1809 1810 link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]); 1811 1812 if (strcmp(link_name, tipc_bclink_name) == 0) { 1813 err = tipc_bclink_reset_stats(net); 1814 if (err) 1815 return err; 1816 return 0; 1817 } 1818 1819 node = tipc_node_find_by_name(net, link_name, &bearer_id); 1820 if (!node) 1821 return -EINVAL; 1822 1823 le = &node->links[bearer_id]; 1824 tipc_node_read_lock(node); 1825 spin_lock_bh(&le->lock); 1826 link = node->links[bearer_id].link; 1827 if (!link) { 1828 spin_unlock_bh(&le->lock); 1829 tipc_node_read_unlock(node); 1830 return -EINVAL; 1831 } 1832 tipc_link_reset_stats(link); 1833 spin_unlock_bh(&le->lock); 1834 tipc_node_read_unlock(node); 1835 return 0; 1836 } 1837 1838 /* Caller should hold node lock */ 1839 static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg, 1840 struct tipc_node *node, u32 *prev_link) 1841 { 1842 u32 i; 1843 int err; 1844 1845 for (i = *prev_link; i < MAX_BEARERS; i++) { 1846 *prev_link = i; 1847 1848 if (!node->links[i].link) 1849 continue; 1850 1851 err = __tipc_nl_add_link(net, msg, 1852 node->links[i].link, NLM_F_MULTI); 1853 if (err) 1854 return err; 1855 } 1856 *prev_link = 0; 1857 1858 return 0; 1859 } 1860 1861 int tipc_nl_node_dump_link(struct sk_buff *skb, struct netlink_callback *cb) 1862 { 1863 struct net *net = sock_net(skb->sk); 1864 struct tipc_net *tn = net_generic(net, tipc_net_id); 1865 struct tipc_node *node; 1866 struct tipc_nl_msg msg; 1867 u32 prev_node = cb->args[0]; 1868 u32 prev_link = cb->args[1]; 1869 int done = cb->args[2]; 1870 int err; 1871 1872 if (done) 1873 return 0; 1874 1875 msg.skb = skb; 1876 msg.portid = NETLINK_CB(cb->skb).portid; 1877 msg.seq = cb->nlh->nlmsg_seq; 1878 1879 rcu_read_lock(); 1880 if (prev_node) { 1881 node = tipc_node_find(net, prev_node); 1882 if (!node) { 1883 /* We never set seq or call nl_dump_check_consistent() 1884 * this means that setting prev_seq here will cause the 1885 * consistence check to fail in the netlink callback 1886 * handler. Resulting in the last NLMSG_DONE message 1887 * having the NLM_F_DUMP_INTR flag set. 1888 */ 1889 cb->prev_seq = 1; 1890 goto out; 1891 } 1892 tipc_node_put(node); 1893 1894 list_for_each_entry_continue_rcu(node, &tn->node_list, 1895 list) { 1896 tipc_node_read_lock(node); 1897 err = __tipc_nl_add_node_links(net, &msg, node, 1898 &prev_link); 1899 tipc_node_read_unlock(node); 1900 if (err) 1901 goto out; 1902 1903 prev_node = node->addr; 1904 } 1905 } else { 1906 err = tipc_nl_add_bc_link(net, &msg); 1907 if (err) 1908 goto out; 1909 1910 list_for_each_entry_rcu(node, &tn->node_list, list) { 1911 tipc_node_read_lock(node); 1912 err = __tipc_nl_add_node_links(net, &msg, node, 1913 &prev_link); 1914 tipc_node_read_unlock(node); 1915 if (err) 1916 goto out; 1917 1918 prev_node = node->addr; 1919 } 1920 } 1921 done = 1; 1922 out: 1923 rcu_read_unlock(); 1924 1925 cb->args[0] = prev_node; 1926 cb->args[1] = prev_link; 1927 cb->args[2] = done; 1928 1929 return skb->len; 1930 } 1931