1 /* 2 * net/tipc/link.c: TIPC link code 3 * 4 * Copyright (c) 1996-2007, 2012-2015, Ericsson AB 5 * Copyright (c) 2004-2007, 2010-2013, 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 "subscr.h" 39 #include "link.h" 40 #include "bcast.h" 41 #include "socket.h" 42 #include "name_distr.h" 43 #include "discover.h" 44 #include "netlink.h" 45 46 #include <linux/pkt_sched.h> 47 48 /* 49 * Error message prefixes 50 */ 51 static const char *link_co_err = "Link tunneling error, "; 52 static const char *link_rst_msg = "Resetting link "; 53 static const char tipc_bclink_name[] = "broadcast-link"; 54 55 static const struct nla_policy tipc_nl_link_policy[TIPC_NLA_LINK_MAX + 1] = { 56 [TIPC_NLA_LINK_UNSPEC] = { .type = NLA_UNSPEC }, 57 [TIPC_NLA_LINK_NAME] = { 58 .type = NLA_STRING, 59 .len = TIPC_MAX_LINK_NAME 60 }, 61 [TIPC_NLA_LINK_MTU] = { .type = NLA_U32 }, 62 [TIPC_NLA_LINK_BROADCAST] = { .type = NLA_FLAG }, 63 [TIPC_NLA_LINK_UP] = { .type = NLA_FLAG }, 64 [TIPC_NLA_LINK_ACTIVE] = { .type = NLA_FLAG }, 65 [TIPC_NLA_LINK_PROP] = { .type = NLA_NESTED }, 66 [TIPC_NLA_LINK_STATS] = { .type = NLA_NESTED }, 67 [TIPC_NLA_LINK_RX] = { .type = NLA_U32 }, 68 [TIPC_NLA_LINK_TX] = { .type = NLA_U32 } 69 }; 70 71 /* Properties valid for media, bearar and link */ 72 static const struct nla_policy tipc_nl_prop_policy[TIPC_NLA_PROP_MAX + 1] = { 73 [TIPC_NLA_PROP_UNSPEC] = { .type = NLA_UNSPEC }, 74 [TIPC_NLA_PROP_PRIO] = { .type = NLA_U32 }, 75 [TIPC_NLA_PROP_TOL] = { .type = NLA_U32 }, 76 [TIPC_NLA_PROP_WIN] = { .type = NLA_U32 } 77 }; 78 79 /* Send states for broadcast NACKs 80 */ 81 enum { 82 BC_NACK_SND_CONDITIONAL, 83 BC_NACK_SND_UNCONDITIONAL, 84 BC_NACK_SND_SUPPRESS, 85 }; 86 87 /* 88 * Interval between NACKs when packets arrive out of order 89 */ 90 #define TIPC_NACK_INTV (TIPC_MIN_LINK_WIN * 2) 91 /* 92 * Out-of-range value for link session numbers 93 */ 94 #define WILDCARD_SESSION 0x10000 95 96 /* Link FSM states: 97 */ 98 enum { 99 LINK_ESTABLISHED = 0xe, 100 LINK_ESTABLISHING = 0xe << 4, 101 LINK_RESET = 0x1 << 8, 102 LINK_RESETTING = 0x2 << 12, 103 LINK_PEER_RESET = 0xd << 16, 104 LINK_FAILINGOVER = 0xf << 20, 105 LINK_SYNCHING = 0xc << 24 106 }; 107 108 /* Link FSM state checking routines 109 */ 110 static int link_is_up(struct tipc_link *l) 111 { 112 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING); 113 } 114 115 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb, 116 struct sk_buff_head *xmitq); 117 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe, 118 u16 rcvgap, int tolerance, int priority, 119 struct sk_buff_head *xmitq); 120 static void link_reset_statistics(struct tipc_link *l_ptr); 121 static void link_print(struct tipc_link *l_ptr, const char *str); 122 static void tipc_link_build_nack_msg(struct tipc_link *l, 123 struct sk_buff_head *xmitq); 124 static void tipc_link_build_bc_init_msg(struct tipc_link *l, 125 struct sk_buff_head *xmitq); 126 static bool tipc_link_release_pkts(struct tipc_link *l, u16 to); 127 128 /* 129 * Simple non-static link routines (i.e. referenced outside this file) 130 */ 131 bool tipc_link_is_up(struct tipc_link *l) 132 { 133 return link_is_up(l); 134 } 135 136 bool tipc_link_peer_is_down(struct tipc_link *l) 137 { 138 return l->state == LINK_PEER_RESET; 139 } 140 141 bool tipc_link_is_reset(struct tipc_link *l) 142 { 143 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING); 144 } 145 146 bool tipc_link_is_establishing(struct tipc_link *l) 147 { 148 return l->state == LINK_ESTABLISHING; 149 } 150 151 bool tipc_link_is_synching(struct tipc_link *l) 152 { 153 return l->state == LINK_SYNCHING; 154 } 155 156 bool tipc_link_is_failingover(struct tipc_link *l) 157 { 158 return l->state == LINK_FAILINGOVER; 159 } 160 161 bool tipc_link_is_blocked(struct tipc_link *l) 162 { 163 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER); 164 } 165 166 static bool link_is_bc_sndlink(struct tipc_link *l) 167 { 168 return !l->bc_sndlink; 169 } 170 171 static bool link_is_bc_rcvlink(struct tipc_link *l) 172 { 173 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l)); 174 } 175 176 int tipc_link_is_active(struct tipc_link *l) 177 { 178 return l->active; 179 } 180 181 void tipc_link_set_active(struct tipc_link *l, bool active) 182 { 183 l->active = active; 184 } 185 186 void tipc_link_add_bc_peer(struct tipc_link *snd_l, 187 struct tipc_link *uc_l, 188 struct sk_buff_head *xmitq) 189 { 190 struct tipc_link *rcv_l = uc_l->bc_rcvlink; 191 192 snd_l->ackers++; 193 rcv_l->acked = snd_l->snd_nxt - 1; 194 snd_l->state = LINK_ESTABLISHED; 195 tipc_link_build_bc_init_msg(uc_l, xmitq); 196 } 197 198 void tipc_link_remove_bc_peer(struct tipc_link *snd_l, 199 struct tipc_link *rcv_l, 200 struct sk_buff_head *xmitq) 201 { 202 u16 ack = snd_l->snd_nxt - 1; 203 204 snd_l->ackers--; 205 tipc_link_bc_ack_rcv(rcv_l, ack, xmitq); 206 tipc_link_reset(rcv_l); 207 rcv_l->state = LINK_RESET; 208 if (!snd_l->ackers) { 209 tipc_link_reset(snd_l); 210 snd_l->state = LINK_RESET; 211 __skb_queue_purge(xmitq); 212 } 213 } 214 215 int tipc_link_bc_peers(struct tipc_link *l) 216 { 217 return l->ackers; 218 } 219 220 void tipc_link_set_mtu(struct tipc_link *l, int mtu) 221 { 222 l->mtu = mtu; 223 } 224 225 int tipc_link_mtu(struct tipc_link *l) 226 { 227 return l->mtu; 228 } 229 230 static u32 link_own_addr(struct tipc_link *l) 231 { 232 return msg_prevnode(l->pmsg); 233 } 234 235 /** 236 * tipc_link_create - create a new link 237 * @n: pointer to associated node 238 * @if_name: associated interface name 239 * @bearer_id: id (index) of associated bearer 240 * @tolerance: link tolerance to be used by link 241 * @net_plane: network plane (A,B,c..) this link belongs to 242 * @mtu: mtu to be advertised by link 243 * @priority: priority to be used by link 244 * @window: send window to be used by link 245 * @session: session to be used by link 246 * @ownnode: identity of own node 247 * @peer: node id of peer node 248 * @peer_caps: bitmap describing peer node capabilities 249 * @bc_sndlink: the namespace global link used for broadcast sending 250 * @bc_rcvlink: the peer specific link used for broadcast reception 251 * @inputq: queue to put messages ready for delivery 252 * @namedq: queue to put binding table update messages ready for delivery 253 * @link: return value, pointer to put the created link 254 * 255 * Returns true if link was created, otherwise false 256 */ 257 bool tipc_link_create(struct net *net, char *if_name, int bearer_id, 258 int tolerance, char net_plane, u32 mtu, int priority, 259 int window, u32 session, u32 ownnode, u32 peer, 260 u16 peer_caps, 261 struct tipc_link *bc_sndlink, 262 struct tipc_link *bc_rcvlink, 263 struct sk_buff_head *inputq, 264 struct sk_buff_head *namedq, 265 struct tipc_link **link) 266 { 267 struct tipc_link *l; 268 struct tipc_msg *hdr; 269 270 l = kzalloc(sizeof(*l), GFP_ATOMIC); 271 if (!l) 272 return false; 273 *link = l; 274 l->pmsg = (struct tipc_msg *)&l->proto_msg; 275 hdr = l->pmsg; 276 tipc_msg_init(ownnode, hdr, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE, peer); 277 msg_set_size(hdr, sizeof(l->proto_msg)); 278 msg_set_session(hdr, session); 279 msg_set_bearer_id(hdr, l->bearer_id); 280 281 /* Note: peer i/f name is completed by reset/activate message */ 282 sprintf(l->name, "%u.%u.%u:%s-%u.%u.%u:unknown", 283 tipc_zone(ownnode), tipc_cluster(ownnode), tipc_node(ownnode), 284 if_name, tipc_zone(peer), tipc_cluster(peer), tipc_node(peer)); 285 strcpy((char *)msg_data(hdr), if_name); 286 287 l->addr = peer; 288 l->peer_caps = peer_caps; 289 l->net = net; 290 l->peer_session = WILDCARD_SESSION; 291 l->bearer_id = bearer_id; 292 l->tolerance = tolerance; 293 l->net_plane = net_plane; 294 l->advertised_mtu = mtu; 295 l->mtu = mtu; 296 l->priority = priority; 297 tipc_link_set_queue_limits(l, window); 298 l->ackers = 1; 299 l->bc_sndlink = bc_sndlink; 300 l->bc_rcvlink = bc_rcvlink; 301 l->inputq = inputq; 302 l->namedq = namedq; 303 l->state = LINK_RESETTING; 304 __skb_queue_head_init(&l->transmq); 305 __skb_queue_head_init(&l->backlogq); 306 __skb_queue_head_init(&l->deferdq); 307 skb_queue_head_init(&l->wakeupq); 308 skb_queue_head_init(l->inputq); 309 return true; 310 } 311 312 /** 313 * tipc_link_bc_create - create new link to be used for broadcast 314 * @n: pointer to associated node 315 * @mtu: mtu to be used 316 * @window: send window to be used 317 * @inputq: queue to put messages ready for delivery 318 * @namedq: queue to put binding table update messages ready for delivery 319 * @link: return value, pointer to put the created link 320 * 321 * Returns true if link was created, otherwise false 322 */ 323 bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer, 324 int mtu, int window, u16 peer_caps, 325 struct sk_buff_head *inputq, 326 struct sk_buff_head *namedq, 327 struct tipc_link *bc_sndlink, 328 struct tipc_link **link) 329 { 330 struct tipc_link *l; 331 332 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, window, 333 0, ownnode, peer, peer_caps, bc_sndlink, 334 NULL, inputq, namedq, link)) 335 return false; 336 337 l = *link; 338 strcpy(l->name, tipc_bclink_name); 339 tipc_link_reset(l); 340 l->state = LINK_RESET; 341 l->ackers = 0; 342 l->bc_rcvlink = l; 343 344 /* Broadcast send link is always up */ 345 if (link_is_bc_sndlink(l)) 346 l->state = LINK_ESTABLISHED; 347 348 return true; 349 } 350 351 /** 352 * tipc_link_fsm_evt - link finite state machine 353 * @l: pointer to link 354 * @evt: state machine event to be processed 355 */ 356 int tipc_link_fsm_evt(struct tipc_link *l, int evt) 357 { 358 int rc = 0; 359 360 switch (l->state) { 361 case LINK_RESETTING: 362 switch (evt) { 363 case LINK_PEER_RESET_EVT: 364 l->state = LINK_PEER_RESET; 365 break; 366 case LINK_RESET_EVT: 367 l->state = LINK_RESET; 368 break; 369 case LINK_FAILURE_EVT: 370 case LINK_FAILOVER_BEGIN_EVT: 371 case LINK_ESTABLISH_EVT: 372 case LINK_FAILOVER_END_EVT: 373 case LINK_SYNCH_BEGIN_EVT: 374 case LINK_SYNCH_END_EVT: 375 default: 376 goto illegal_evt; 377 } 378 break; 379 case LINK_RESET: 380 switch (evt) { 381 case LINK_PEER_RESET_EVT: 382 l->state = LINK_ESTABLISHING; 383 break; 384 case LINK_FAILOVER_BEGIN_EVT: 385 l->state = LINK_FAILINGOVER; 386 case LINK_FAILURE_EVT: 387 case LINK_RESET_EVT: 388 case LINK_ESTABLISH_EVT: 389 case LINK_FAILOVER_END_EVT: 390 break; 391 case LINK_SYNCH_BEGIN_EVT: 392 case LINK_SYNCH_END_EVT: 393 default: 394 goto illegal_evt; 395 } 396 break; 397 case LINK_PEER_RESET: 398 switch (evt) { 399 case LINK_RESET_EVT: 400 l->state = LINK_ESTABLISHING; 401 break; 402 case LINK_PEER_RESET_EVT: 403 case LINK_ESTABLISH_EVT: 404 case LINK_FAILURE_EVT: 405 break; 406 case LINK_SYNCH_BEGIN_EVT: 407 case LINK_SYNCH_END_EVT: 408 case LINK_FAILOVER_BEGIN_EVT: 409 case LINK_FAILOVER_END_EVT: 410 default: 411 goto illegal_evt; 412 } 413 break; 414 case LINK_FAILINGOVER: 415 switch (evt) { 416 case LINK_FAILOVER_END_EVT: 417 l->state = LINK_RESET; 418 break; 419 case LINK_PEER_RESET_EVT: 420 case LINK_RESET_EVT: 421 case LINK_ESTABLISH_EVT: 422 case LINK_FAILURE_EVT: 423 break; 424 case LINK_FAILOVER_BEGIN_EVT: 425 case LINK_SYNCH_BEGIN_EVT: 426 case LINK_SYNCH_END_EVT: 427 default: 428 goto illegal_evt; 429 } 430 break; 431 case LINK_ESTABLISHING: 432 switch (evt) { 433 case LINK_ESTABLISH_EVT: 434 l->state = LINK_ESTABLISHED; 435 break; 436 case LINK_FAILOVER_BEGIN_EVT: 437 l->state = LINK_FAILINGOVER; 438 break; 439 case LINK_RESET_EVT: 440 l->state = LINK_RESET; 441 break; 442 case LINK_FAILURE_EVT: 443 case LINK_PEER_RESET_EVT: 444 case LINK_SYNCH_BEGIN_EVT: 445 case LINK_FAILOVER_END_EVT: 446 break; 447 case LINK_SYNCH_END_EVT: 448 default: 449 goto illegal_evt; 450 } 451 break; 452 case LINK_ESTABLISHED: 453 switch (evt) { 454 case LINK_PEER_RESET_EVT: 455 l->state = LINK_PEER_RESET; 456 rc |= TIPC_LINK_DOWN_EVT; 457 break; 458 case LINK_FAILURE_EVT: 459 l->state = LINK_RESETTING; 460 rc |= TIPC_LINK_DOWN_EVT; 461 break; 462 case LINK_RESET_EVT: 463 l->state = LINK_RESET; 464 break; 465 case LINK_ESTABLISH_EVT: 466 case LINK_SYNCH_END_EVT: 467 break; 468 case LINK_SYNCH_BEGIN_EVT: 469 l->state = LINK_SYNCHING; 470 break; 471 case LINK_FAILOVER_BEGIN_EVT: 472 case LINK_FAILOVER_END_EVT: 473 default: 474 goto illegal_evt; 475 } 476 break; 477 case LINK_SYNCHING: 478 switch (evt) { 479 case LINK_PEER_RESET_EVT: 480 l->state = LINK_PEER_RESET; 481 rc |= TIPC_LINK_DOWN_EVT; 482 break; 483 case LINK_FAILURE_EVT: 484 l->state = LINK_RESETTING; 485 rc |= TIPC_LINK_DOWN_EVT; 486 break; 487 case LINK_RESET_EVT: 488 l->state = LINK_RESET; 489 break; 490 case LINK_ESTABLISH_EVT: 491 case LINK_SYNCH_BEGIN_EVT: 492 break; 493 case LINK_SYNCH_END_EVT: 494 l->state = LINK_ESTABLISHED; 495 break; 496 case LINK_FAILOVER_BEGIN_EVT: 497 case LINK_FAILOVER_END_EVT: 498 default: 499 goto illegal_evt; 500 } 501 break; 502 default: 503 pr_err("Unknown FSM state %x in %s\n", l->state, l->name); 504 } 505 return rc; 506 illegal_evt: 507 pr_err("Illegal FSM event %x in state %x on link %s\n", 508 evt, l->state, l->name); 509 return rc; 510 } 511 512 /* link_profile_stats - update statistical profiling of traffic 513 */ 514 static void link_profile_stats(struct tipc_link *l) 515 { 516 struct sk_buff *skb; 517 struct tipc_msg *msg; 518 int length; 519 520 /* Update counters used in statistical profiling of send traffic */ 521 l->stats.accu_queue_sz += skb_queue_len(&l->transmq); 522 l->stats.queue_sz_counts++; 523 524 skb = skb_peek(&l->transmq); 525 if (!skb) 526 return; 527 msg = buf_msg(skb); 528 length = msg_size(msg); 529 530 if (msg_user(msg) == MSG_FRAGMENTER) { 531 if (msg_type(msg) != FIRST_FRAGMENT) 532 return; 533 length = msg_size(msg_get_wrapped(msg)); 534 } 535 l->stats.msg_lengths_total += length; 536 l->stats.msg_length_counts++; 537 if (length <= 64) 538 l->stats.msg_length_profile[0]++; 539 else if (length <= 256) 540 l->stats.msg_length_profile[1]++; 541 else if (length <= 1024) 542 l->stats.msg_length_profile[2]++; 543 else if (length <= 4096) 544 l->stats.msg_length_profile[3]++; 545 else if (length <= 16384) 546 l->stats.msg_length_profile[4]++; 547 else if (length <= 32768) 548 l->stats.msg_length_profile[5]++; 549 else 550 l->stats.msg_length_profile[6]++; 551 } 552 553 /* tipc_link_timeout - perform periodic task as instructed from node timeout 554 */ 555 /* tipc_link_timeout - perform periodic task as instructed from node timeout 556 */ 557 int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq) 558 { 559 int rc = 0; 560 int mtyp = STATE_MSG; 561 bool xmit = false; 562 bool prb = false; 563 u16 bc_snt = l->bc_sndlink->snd_nxt - 1; 564 u16 bc_acked = l->bc_rcvlink->acked; 565 bool bc_up = link_is_up(l->bc_rcvlink); 566 567 link_profile_stats(l); 568 569 switch (l->state) { 570 case LINK_ESTABLISHED: 571 case LINK_SYNCHING: 572 if (!l->silent_intv_cnt) { 573 if (bc_up && (bc_acked != bc_snt)) 574 xmit = true; 575 } else if (l->silent_intv_cnt <= l->abort_limit) { 576 xmit = true; 577 prb = true; 578 } else { 579 rc |= tipc_link_fsm_evt(l, LINK_FAILURE_EVT); 580 } 581 l->silent_intv_cnt++; 582 break; 583 case LINK_RESET: 584 xmit = true; 585 mtyp = RESET_MSG; 586 break; 587 case LINK_ESTABLISHING: 588 xmit = true; 589 mtyp = ACTIVATE_MSG; 590 break; 591 case LINK_PEER_RESET: 592 case LINK_RESETTING: 593 case LINK_FAILINGOVER: 594 break; 595 default: 596 break; 597 } 598 599 if (xmit) 600 tipc_link_build_proto_msg(l, mtyp, prb, 0, 0, 0, xmitq); 601 602 return rc; 603 } 604 605 /** 606 * link_schedule_user - schedule a message sender for wakeup after congestion 607 * @link: congested link 608 * @list: message that was attempted sent 609 * Create pseudo msg to send back to user when congestion abates 610 * Does not consume buffer list 611 */ 612 static int link_schedule_user(struct tipc_link *link, struct sk_buff_head *list) 613 { 614 struct tipc_msg *msg = buf_msg(skb_peek(list)); 615 int imp = msg_importance(msg); 616 u32 oport = msg_origport(msg); 617 u32 addr = link_own_addr(link); 618 struct sk_buff *skb; 619 620 /* This really cannot happen... */ 621 if (unlikely(imp > TIPC_CRITICAL_IMPORTANCE)) { 622 pr_warn("%s<%s>, send queue full", link_rst_msg, link->name); 623 return -ENOBUFS; 624 } 625 /* Non-blocking sender: */ 626 if (TIPC_SKB_CB(skb_peek(list))->wakeup_pending) 627 return -ELINKCONG; 628 629 /* Create and schedule wakeup pseudo message */ 630 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0, 631 addr, addr, oport, 0, 0); 632 if (!skb) 633 return -ENOBUFS; 634 TIPC_SKB_CB(skb)->chain_sz = skb_queue_len(list); 635 TIPC_SKB_CB(skb)->chain_imp = imp; 636 skb_queue_tail(&link->wakeupq, skb); 637 link->stats.link_congs++; 638 return -ELINKCONG; 639 } 640 641 /** 642 * link_prepare_wakeup - prepare users for wakeup after congestion 643 * @link: congested link 644 * Move a number of waiting users, as permitted by available space in 645 * the send queue, from link wait queue to node wait queue for wakeup 646 */ 647 void link_prepare_wakeup(struct tipc_link *l) 648 { 649 int pnd[TIPC_SYSTEM_IMPORTANCE + 1] = {0,}; 650 int imp, lim; 651 struct sk_buff *skb, *tmp; 652 653 skb_queue_walk_safe(&l->wakeupq, skb, tmp) { 654 imp = TIPC_SKB_CB(skb)->chain_imp; 655 lim = l->window + l->backlog[imp].limit; 656 pnd[imp] += TIPC_SKB_CB(skb)->chain_sz; 657 if ((pnd[imp] + l->backlog[imp].len) >= lim) 658 break; 659 skb_unlink(skb, &l->wakeupq); 660 skb_queue_tail(l->inputq, skb); 661 } 662 } 663 664 void tipc_link_reset(struct tipc_link *l) 665 { 666 /* Link is down, accept any session */ 667 l->peer_session = WILDCARD_SESSION; 668 669 /* If peer is up, it only accepts an incremented session number */ 670 msg_set_session(l->pmsg, msg_session(l->pmsg) + 1); 671 672 /* Prepare for renewed mtu size negotiation */ 673 l->mtu = l->advertised_mtu; 674 675 /* Clean up all queues and counters: */ 676 __skb_queue_purge(&l->transmq); 677 __skb_queue_purge(&l->deferdq); 678 skb_queue_splice_init(&l->wakeupq, l->inputq); 679 __skb_queue_purge(&l->backlogq); 680 l->backlog[TIPC_LOW_IMPORTANCE].len = 0; 681 l->backlog[TIPC_MEDIUM_IMPORTANCE].len = 0; 682 l->backlog[TIPC_HIGH_IMPORTANCE].len = 0; 683 l->backlog[TIPC_CRITICAL_IMPORTANCE].len = 0; 684 l->backlog[TIPC_SYSTEM_IMPORTANCE].len = 0; 685 kfree_skb(l->reasm_buf); 686 kfree_skb(l->failover_reasm_skb); 687 l->reasm_buf = NULL; 688 l->failover_reasm_skb = NULL; 689 l->rcv_unacked = 0; 690 l->snd_nxt = 1; 691 l->rcv_nxt = 1; 692 l->acked = 0; 693 l->silent_intv_cnt = 0; 694 l->stats.recv_info = 0; 695 l->stale_count = 0; 696 l->bc_peer_is_up = false; 697 link_reset_statistics(l); 698 } 699 700 /** 701 * tipc_link_xmit(): enqueue buffer list according to queue situation 702 * @link: link to use 703 * @list: chain of buffers containing message 704 * @xmitq: returned list of packets to be sent by caller 705 * 706 * Consumes the buffer chain, except when returning -ELINKCONG, 707 * since the caller then may want to make more send attempts. 708 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS 709 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted 710 */ 711 int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list, 712 struct sk_buff_head *xmitq) 713 { 714 struct tipc_msg *hdr = buf_msg(skb_peek(list)); 715 unsigned int maxwin = l->window; 716 unsigned int i, imp = msg_importance(hdr); 717 unsigned int mtu = l->mtu; 718 u16 ack = l->rcv_nxt - 1; 719 u16 seqno = l->snd_nxt; 720 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1; 721 struct sk_buff_head *transmq = &l->transmq; 722 struct sk_buff_head *backlogq = &l->backlogq; 723 struct sk_buff *skb, *_skb, *bskb; 724 725 /* Match msg importance against this and all higher backlog limits: */ 726 for (i = imp; i <= TIPC_SYSTEM_IMPORTANCE; i++) { 727 if (unlikely(l->backlog[i].len >= l->backlog[i].limit)) 728 return link_schedule_user(l, list); 729 } 730 if (unlikely(msg_size(hdr) > mtu)) 731 return -EMSGSIZE; 732 733 /* Prepare each packet for sending, and add to relevant queue: */ 734 while (skb_queue_len(list)) { 735 skb = skb_peek(list); 736 hdr = buf_msg(skb); 737 msg_set_seqno(hdr, seqno); 738 msg_set_ack(hdr, ack); 739 msg_set_bcast_ack(hdr, bc_ack); 740 741 if (likely(skb_queue_len(transmq) < maxwin)) { 742 _skb = skb_clone(skb, GFP_ATOMIC); 743 if (!_skb) 744 return -ENOBUFS; 745 __skb_dequeue(list); 746 __skb_queue_tail(transmq, skb); 747 __skb_queue_tail(xmitq, _skb); 748 TIPC_SKB_CB(skb)->ackers = l->ackers; 749 l->rcv_unacked = 0; 750 seqno++; 751 continue; 752 } 753 if (tipc_msg_bundle(skb_peek_tail(backlogq), hdr, mtu)) { 754 kfree_skb(__skb_dequeue(list)); 755 l->stats.sent_bundled++; 756 continue; 757 } 758 if (tipc_msg_make_bundle(&bskb, hdr, mtu, l->addr)) { 759 kfree_skb(__skb_dequeue(list)); 760 __skb_queue_tail(backlogq, bskb); 761 l->backlog[msg_importance(buf_msg(bskb))].len++; 762 l->stats.sent_bundled++; 763 l->stats.sent_bundles++; 764 continue; 765 } 766 l->backlog[imp].len += skb_queue_len(list); 767 skb_queue_splice_tail_init(list, backlogq); 768 } 769 l->snd_nxt = seqno; 770 return 0; 771 } 772 773 void tipc_link_advance_backlog(struct tipc_link *l, struct sk_buff_head *xmitq) 774 { 775 struct sk_buff *skb, *_skb; 776 struct tipc_msg *hdr; 777 u16 seqno = l->snd_nxt; 778 u16 ack = l->rcv_nxt - 1; 779 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1; 780 781 while (skb_queue_len(&l->transmq) < l->window) { 782 skb = skb_peek(&l->backlogq); 783 if (!skb) 784 break; 785 _skb = skb_clone(skb, GFP_ATOMIC); 786 if (!_skb) 787 break; 788 __skb_dequeue(&l->backlogq); 789 hdr = buf_msg(skb); 790 l->backlog[msg_importance(hdr)].len--; 791 __skb_queue_tail(&l->transmq, skb); 792 __skb_queue_tail(xmitq, _skb); 793 TIPC_SKB_CB(skb)->ackers = l->ackers; 794 msg_set_seqno(hdr, seqno); 795 msg_set_ack(hdr, ack); 796 msg_set_bcast_ack(hdr, bc_ack); 797 l->rcv_unacked = 0; 798 seqno++; 799 } 800 l->snd_nxt = seqno; 801 } 802 803 static void link_retransmit_failure(struct tipc_link *l, struct sk_buff *skb) 804 { 805 struct tipc_msg *hdr = buf_msg(skb); 806 807 pr_warn("Retransmission failure on link <%s>\n", l->name); 808 link_print(l, "Resetting link "); 809 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n", 810 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr)); 811 pr_info("sqno %u, prev: %x, src: %x\n", 812 msg_seqno(hdr), msg_prevnode(hdr), msg_orignode(hdr)); 813 } 814 815 int tipc_link_retrans(struct tipc_link *l, u16 from, u16 to, 816 struct sk_buff_head *xmitq) 817 { 818 struct sk_buff *_skb, *skb = skb_peek(&l->transmq); 819 struct tipc_msg *hdr; 820 u16 ack = l->rcv_nxt - 1; 821 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1; 822 823 if (!skb) 824 return 0; 825 826 /* Detect repeated retransmit failures on same packet */ 827 if (likely(l->last_retransm != buf_seqno(skb))) { 828 l->last_retransm = buf_seqno(skb); 829 l->stale_count = 1; 830 } else if (++l->stale_count > 100) { 831 link_retransmit_failure(l, skb); 832 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT); 833 } 834 835 /* Move forward to where retransmission should start */ 836 skb_queue_walk(&l->transmq, skb) { 837 if (!less(buf_seqno(skb), from)) 838 break; 839 } 840 841 skb_queue_walk_from(&l->transmq, skb) { 842 if (more(buf_seqno(skb), to)) 843 break; 844 hdr = buf_msg(skb); 845 _skb = __pskb_copy(skb, MIN_H_SIZE, GFP_ATOMIC); 846 if (!_skb) 847 return 0; 848 hdr = buf_msg(_skb); 849 msg_set_ack(hdr, ack); 850 msg_set_bcast_ack(hdr, bc_ack); 851 _skb->priority = TC_PRIO_CONTROL; 852 __skb_queue_tail(xmitq, _skb); 853 l->stats.retransmitted++; 854 } 855 return 0; 856 } 857 858 /* tipc_data_input - deliver data and name distr msgs to upper layer 859 * 860 * Consumes buffer if message is of right type 861 * Node lock must be held 862 */ 863 static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb, 864 struct sk_buff_head *inputq) 865 { 866 switch (msg_user(buf_msg(skb))) { 867 case TIPC_LOW_IMPORTANCE: 868 case TIPC_MEDIUM_IMPORTANCE: 869 case TIPC_HIGH_IMPORTANCE: 870 case TIPC_CRITICAL_IMPORTANCE: 871 case CONN_MANAGER: 872 skb_queue_tail(inputq, skb); 873 return true; 874 case NAME_DISTRIBUTOR: 875 l->bc_rcvlink->state = LINK_ESTABLISHED; 876 skb_queue_tail(l->namedq, skb); 877 return true; 878 case MSG_BUNDLER: 879 case TUNNEL_PROTOCOL: 880 case MSG_FRAGMENTER: 881 case BCAST_PROTOCOL: 882 return false; 883 default: 884 pr_warn("Dropping received illegal msg type\n"); 885 kfree_skb(skb); 886 return false; 887 }; 888 } 889 890 /* tipc_link_input - process packet that has passed link protocol check 891 * 892 * Consumes buffer 893 */ 894 static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb, 895 struct sk_buff_head *inputq) 896 { 897 struct tipc_msg *hdr = buf_msg(skb); 898 struct sk_buff **reasm_skb = &l->reasm_buf; 899 struct sk_buff *iskb; 900 struct sk_buff_head tmpq; 901 int usr = msg_user(hdr); 902 int rc = 0; 903 int pos = 0; 904 int ipos = 0; 905 906 if (unlikely(usr == TUNNEL_PROTOCOL)) { 907 if (msg_type(hdr) == SYNCH_MSG) { 908 __skb_queue_purge(&l->deferdq); 909 goto drop; 910 } 911 if (!tipc_msg_extract(skb, &iskb, &ipos)) 912 return rc; 913 kfree_skb(skb); 914 skb = iskb; 915 hdr = buf_msg(skb); 916 if (less(msg_seqno(hdr), l->drop_point)) 917 goto drop; 918 if (tipc_data_input(l, skb, inputq)) 919 return rc; 920 usr = msg_user(hdr); 921 reasm_skb = &l->failover_reasm_skb; 922 } 923 924 if (usr == MSG_BUNDLER) { 925 skb_queue_head_init(&tmpq); 926 l->stats.recv_bundles++; 927 l->stats.recv_bundled += msg_msgcnt(hdr); 928 while (tipc_msg_extract(skb, &iskb, &pos)) 929 tipc_data_input(l, iskb, &tmpq); 930 tipc_skb_queue_splice_tail(&tmpq, inputq); 931 return 0; 932 } else if (usr == MSG_FRAGMENTER) { 933 l->stats.recv_fragments++; 934 if (tipc_buf_append(reasm_skb, &skb)) { 935 l->stats.recv_fragmented++; 936 tipc_data_input(l, skb, inputq); 937 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) { 938 pr_warn_ratelimited("Unable to build fragment list\n"); 939 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT); 940 } 941 return 0; 942 } else if (usr == BCAST_PROTOCOL) { 943 tipc_bcast_lock(l->net); 944 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr); 945 tipc_bcast_unlock(l->net); 946 } 947 drop: 948 kfree_skb(skb); 949 return 0; 950 } 951 952 static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked) 953 { 954 bool released = false; 955 struct sk_buff *skb, *tmp; 956 957 skb_queue_walk_safe(&l->transmq, skb, tmp) { 958 if (more(buf_seqno(skb), acked)) 959 break; 960 __skb_unlink(skb, &l->transmq); 961 kfree_skb(skb); 962 released = true; 963 } 964 return released; 965 } 966 967 /* tipc_link_build_ack_msg: prepare link acknowledge message for transmission 968 * 969 * Note that sending of broadcast ack is coordinated among nodes, to reduce 970 * risk of ack storms towards the sender 971 */ 972 int tipc_link_build_ack_msg(struct tipc_link *l, struct sk_buff_head *xmitq) 973 { 974 if (!l) 975 return 0; 976 977 /* Broadcast ACK must be sent via a unicast link => defer to caller */ 978 if (link_is_bc_rcvlink(l)) { 979 if (((l->rcv_nxt ^ link_own_addr(l)) & 0xf) != 0xf) 980 return 0; 981 l->rcv_unacked = 0; 982 return TIPC_LINK_SND_BC_ACK; 983 } 984 985 /* Unicast ACK */ 986 l->rcv_unacked = 0; 987 l->stats.sent_acks++; 988 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq); 989 return 0; 990 } 991 992 /* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message 993 */ 994 void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq) 995 { 996 int mtyp = RESET_MSG; 997 998 if (l->state == LINK_ESTABLISHING) 999 mtyp = ACTIVATE_MSG; 1000 1001 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, xmitq); 1002 } 1003 1004 /* tipc_link_build_nack_msg: prepare link nack message for transmission 1005 */ 1006 static void tipc_link_build_nack_msg(struct tipc_link *l, 1007 struct sk_buff_head *xmitq) 1008 { 1009 u32 def_cnt = ++l->stats.deferred_recv; 1010 1011 if (link_is_bc_rcvlink(l)) 1012 return; 1013 1014 if ((skb_queue_len(&l->deferdq) == 1) || !(def_cnt % TIPC_NACK_INTV)) 1015 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq); 1016 } 1017 1018 /* tipc_link_rcv - process TIPC packets/messages arriving from off-node 1019 * @l: the link that should handle the message 1020 * @skb: TIPC packet 1021 * @xmitq: queue to place packets to be sent after this call 1022 */ 1023 int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb, 1024 struct sk_buff_head *xmitq) 1025 { 1026 struct sk_buff_head *defq = &l->deferdq; 1027 struct tipc_msg *hdr; 1028 u16 seqno, rcv_nxt, win_lim; 1029 int rc = 0; 1030 1031 do { 1032 hdr = buf_msg(skb); 1033 seqno = msg_seqno(hdr); 1034 rcv_nxt = l->rcv_nxt; 1035 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN; 1036 1037 /* Verify and update link state */ 1038 if (unlikely(msg_user(hdr) == LINK_PROTOCOL)) 1039 return tipc_link_proto_rcv(l, skb, xmitq); 1040 1041 if (unlikely(!link_is_up(l))) { 1042 if (l->state == LINK_ESTABLISHING) 1043 rc = TIPC_LINK_UP_EVT; 1044 goto drop; 1045 } 1046 1047 /* Don't send probe at next timeout expiration */ 1048 l->silent_intv_cnt = 0; 1049 1050 /* Drop if outside receive window */ 1051 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) { 1052 l->stats.duplicates++; 1053 goto drop; 1054 } 1055 1056 /* Forward queues and wake up waiting users */ 1057 if (likely(tipc_link_release_pkts(l, msg_ack(hdr)))) { 1058 tipc_link_advance_backlog(l, xmitq); 1059 if (unlikely(!skb_queue_empty(&l->wakeupq))) 1060 link_prepare_wakeup(l); 1061 } 1062 1063 /* Defer delivery if sequence gap */ 1064 if (unlikely(seqno != rcv_nxt)) { 1065 __tipc_skb_queue_sorted(defq, seqno, skb); 1066 tipc_link_build_nack_msg(l, xmitq); 1067 break; 1068 } 1069 1070 /* Deliver packet */ 1071 l->rcv_nxt++; 1072 l->stats.recv_info++; 1073 if (!tipc_data_input(l, skb, l->inputq)) 1074 rc |= tipc_link_input(l, skb, l->inputq); 1075 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN)) 1076 rc |= tipc_link_build_ack_msg(l, xmitq); 1077 if (unlikely(rc & ~TIPC_LINK_SND_BC_ACK)) 1078 break; 1079 } while ((skb = __skb_dequeue(defq))); 1080 1081 return rc; 1082 drop: 1083 kfree_skb(skb); 1084 return rc; 1085 } 1086 1087 /* 1088 * Send protocol message to the other endpoint. 1089 */ 1090 void tipc_link_proto_xmit(struct tipc_link *l, u32 msg_typ, int probe_msg, 1091 u32 gap, u32 tolerance, u32 priority) 1092 { 1093 struct sk_buff *skb = NULL; 1094 struct sk_buff_head xmitq; 1095 1096 __skb_queue_head_init(&xmitq); 1097 tipc_link_build_proto_msg(l, msg_typ, probe_msg, gap, 1098 tolerance, priority, &xmitq); 1099 skb = __skb_dequeue(&xmitq); 1100 if (!skb) 1101 return; 1102 tipc_bearer_xmit_skb(l->net, l->bearer_id, skb, l->media_addr); 1103 l->rcv_unacked = 0; 1104 } 1105 1106 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe, 1107 u16 rcvgap, int tolerance, int priority, 1108 struct sk_buff_head *xmitq) 1109 { 1110 struct sk_buff *skb = NULL; 1111 struct tipc_msg *hdr = l->pmsg; 1112 bool node_up = link_is_up(l->bc_rcvlink); 1113 1114 /* Don't send protocol message during reset or link failover */ 1115 if (tipc_link_is_blocked(l)) 1116 return; 1117 1118 msg_set_type(hdr, mtyp); 1119 msg_set_net_plane(hdr, l->net_plane); 1120 msg_set_next_sent(hdr, l->snd_nxt); 1121 msg_set_ack(hdr, l->rcv_nxt - 1); 1122 msg_set_bcast_ack(hdr, l->bc_rcvlink->rcv_nxt - 1); 1123 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1); 1124 msg_set_link_tolerance(hdr, tolerance); 1125 msg_set_linkprio(hdr, priority); 1126 msg_set_redundant_link(hdr, node_up); 1127 msg_set_seq_gap(hdr, 0); 1128 1129 /* Compatibility: created msg must not be in sequence with pkt flow */ 1130 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2); 1131 1132 if (mtyp == STATE_MSG) { 1133 if (!tipc_link_is_up(l)) 1134 return; 1135 1136 /* Override rcvgap if there are packets in deferred queue */ 1137 if (!skb_queue_empty(&l->deferdq)) 1138 rcvgap = buf_seqno(skb_peek(&l->deferdq)) - l->rcv_nxt; 1139 if (rcvgap) { 1140 msg_set_seq_gap(hdr, rcvgap); 1141 l->stats.sent_nacks++; 1142 } 1143 msg_set_probe(hdr, probe); 1144 if (probe) 1145 l->stats.sent_probes++; 1146 l->stats.sent_states++; 1147 l->rcv_unacked = 0; 1148 } else { 1149 /* RESET_MSG or ACTIVATE_MSG */ 1150 msg_set_max_pkt(hdr, l->advertised_mtu); 1151 msg_set_ack(hdr, l->rcv_nxt - 1); 1152 msg_set_next_sent(hdr, 1); 1153 } 1154 skb = tipc_buf_acquire(msg_size(hdr)); 1155 if (!skb) 1156 return; 1157 skb_copy_to_linear_data(skb, hdr, msg_size(hdr)); 1158 skb->priority = TC_PRIO_CONTROL; 1159 __skb_queue_tail(xmitq, skb); 1160 } 1161 1162 /* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets 1163 * with contents of the link's transmit and backlog queues. 1164 */ 1165 void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl, 1166 int mtyp, struct sk_buff_head *xmitq) 1167 { 1168 struct sk_buff *skb, *tnlskb; 1169 struct tipc_msg *hdr, tnlhdr; 1170 struct sk_buff_head *queue = &l->transmq; 1171 struct sk_buff_head tmpxq, tnlq; 1172 u16 pktlen, pktcnt, seqno = l->snd_nxt; 1173 1174 if (!tnl) 1175 return; 1176 1177 skb_queue_head_init(&tnlq); 1178 skb_queue_head_init(&tmpxq); 1179 1180 /* At least one packet required for safe algorithm => add dummy */ 1181 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG, 1182 BASIC_H_SIZE, 0, l->addr, link_own_addr(l), 1183 0, 0, TIPC_ERR_NO_PORT); 1184 if (!skb) { 1185 pr_warn("%sunable to create tunnel packet\n", link_co_err); 1186 return; 1187 } 1188 skb_queue_tail(&tnlq, skb); 1189 tipc_link_xmit(l, &tnlq, &tmpxq); 1190 __skb_queue_purge(&tmpxq); 1191 1192 /* Initialize reusable tunnel packet header */ 1193 tipc_msg_init(link_own_addr(l), &tnlhdr, TUNNEL_PROTOCOL, 1194 mtyp, INT_H_SIZE, l->addr); 1195 pktcnt = skb_queue_len(&l->transmq) + skb_queue_len(&l->backlogq); 1196 msg_set_msgcnt(&tnlhdr, pktcnt); 1197 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id); 1198 tnl: 1199 /* Wrap each packet into a tunnel packet */ 1200 skb_queue_walk(queue, skb) { 1201 hdr = buf_msg(skb); 1202 if (queue == &l->backlogq) 1203 msg_set_seqno(hdr, seqno++); 1204 pktlen = msg_size(hdr); 1205 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE); 1206 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE); 1207 if (!tnlskb) { 1208 pr_warn("%sunable to send packet\n", link_co_err); 1209 return; 1210 } 1211 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE); 1212 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen); 1213 __skb_queue_tail(&tnlq, tnlskb); 1214 } 1215 if (queue != &l->backlogq) { 1216 queue = &l->backlogq; 1217 goto tnl; 1218 } 1219 1220 tipc_link_xmit(tnl, &tnlq, xmitq); 1221 1222 if (mtyp == FAILOVER_MSG) { 1223 tnl->drop_point = l->rcv_nxt; 1224 tnl->failover_reasm_skb = l->reasm_buf; 1225 l->reasm_buf = NULL; 1226 } 1227 } 1228 1229 /* tipc_link_proto_rcv(): receive link level protocol message : 1230 * Note that network plane id propagates through the network, and may 1231 * change at any time. The node with lowest numerical id determines 1232 * network plane 1233 */ 1234 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb, 1235 struct sk_buff_head *xmitq) 1236 { 1237 struct tipc_msg *hdr = buf_msg(skb); 1238 u16 rcvgap = 0; 1239 u16 ack = msg_ack(hdr); 1240 u16 gap = msg_seq_gap(hdr); 1241 u16 peers_snd_nxt = msg_next_sent(hdr); 1242 u16 peers_tol = msg_link_tolerance(hdr); 1243 u16 peers_prio = msg_linkprio(hdr); 1244 u16 rcv_nxt = l->rcv_nxt; 1245 int mtyp = msg_type(hdr); 1246 char *if_name; 1247 int rc = 0; 1248 1249 if (tipc_link_is_blocked(l) || !xmitq) 1250 goto exit; 1251 1252 if (link_own_addr(l) > msg_prevnode(hdr)) 1253 l->net_plane = msg_net_plane(hdr); 1254 1255 switch (mtyp) { 1256 case RESET_MSG: 1257 1258 /* Ignore duplicate RESET with old session number */ 1259 if ((less_eq(msg_session(hdr), l->peer_session)) && 1260 (l->peer_session != WILDCARD_SESSION)) 1261 break; 1262 /* fall thru' */ 1263 1264 case ACTIVATE_MSG: 1265 1266 /* Complete own link name with peer's interface name */ 1267 if_name = strrchr(l->name, ':') + 1; 1268 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME) 1269 break; 1270 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME) 1271 break; 1272 strncpy(if_name, msg_data(hdr), TIPC_MAX_IF_NAME); 1273 1274 /* Update own tolerance if peer indicates a non-zero value */ 1275 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) 1276 l->tolerance = peers_tol; 1277 1278 /* Update own priority if peer's priority is higher */ 1279 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI)) 1280 l->priority = peers_prio; 1281 1282 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */ 1283 if ((mtyp == RESET_MSG) || !link_is_up(l)) 1284 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT); 1285 1286 /* ACTIVATE_MSG takes up link if it was already locally reset */ 1287 if ((mtyp == ACTIVATE_MSG) && (l->state == LINK_ESTABLISHING)) 1288 rc = TIPC_LINK_UP_EVT; 1289 1290 l->peer_session = msg_session(hdr); 1291 l->peer_bearer_id = msg_bearer_id(hdr); 1292 if (l->mtu > msg_max_pkt(hdr)) 1293 l->mtu = msg_max_pkt(hdr); 1294 break; 1295 1296 case STATE_MSG: 1297 1298 /* Update own tolerance if peer indicates a non-zero value */ 1299 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) 1300 l->tolerance = peers_tol; 1301 1302 l->silent_intv_cnt = 0; 1303 l->stats.recv_states++; 1304 if (msg_probe(hdr)) 1305 l->stats.recv_probes++; 1306 1307 if (!link_is_up(l)) { 1308 if (l->state == LINK_ESTABLISHING) 1309 rc = TIPC_LINK_UP_EVT; 1310 break; 1311 } 1312 1313 /* Send NACK if peer has sent pkts we haven't received yet */ 1314 if (more(peers_snd_nxt, rcv_nxt) && !tipc_link_is_synching(l)) 1315 rcvgap = peers_snd_nxt - l->rcv_nxt; 1316 if (rcvgap || (msg_probe(hdr))) 1317 tipc_link_build_proto_msg(l, STATE_MSG, 0, rcvgap, 1318 0, 0, xmitq); 1319 tipc_link_release_pkts(l, ack); 1320 1321 /* If NACK, retransmit will now start at right position */ 1322 if (gap) { 1323 rc = tipc_link_retrans(l, ack + 1, ack + gap, xmitq); 1324 l->stats.recv_nacks++; 1325 } 1326 1327 tipc_link_advance_backlog(l, xmitq); 1328 if (unlikely(!skb_queue_empty(&l->wakeupq))) 1329 link_prepare_wakeup(l); 1330 } 1331 exit: 1332 kfree_skb(skb); 1333 return rc; 1334 } 1335 1336 /* tipc_link_build_bc_proto_msg() - create broadcast protocol message 1337 */ 1338 static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast, 1339 u16 peers_snd_nxt, 1340 struct sk_buff_head *xmitq) 1341 { 1342 struct sk_buff *skb; 1343 struct tipc_msg *hdr; 1344 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq); 1345 u16 ack = l->rcv_nxt - 1; 1346 u16 gap_to = peers_snd_nxt - 1; 1347 1348 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE, 1349 0, l->addr, link_own_addr(l), 0, 0, 0); 1350 if (!skb) 1351 return false; 1352 hdr = buf_msg(skb); 1353 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1); 1354 msg_set_bcast_ack(hdr, ack); 1355 msg_set_bcgap_after(hdr, ack); 1356 if (dfrd_skb) 1357 gap_to = buf_seqno(dfrd_skb) - 1; 1358 msg_set_bcgap_to(hdr, gap_to); 1359 msg_set_non_seq(hdr, bcast); 1360 __skb_queue_tail(xmitq, skb); 1361 return true; 1362 } 1363 1364 /* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints. 1365 * 1366 * Give a newly added peer node the sequence number where it should 1367 * start receiving and acking broadcast packets. 1368 */ 1369 static void tipc_link_build_bc_init_msg(struct tipc_link *l, 1370 struct sk_buff_head *xmitq) 1371 { 1372 struct sk_buff_head list; 1373 1374 __skb_queue_head_init(&list); 1375 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list)) 1376 return; 1377 tipc_link_xmit(l, &list, xmitq); 1378 } 1379 1380 /* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer 1381 */ 1382 void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr) 1383 { 1384 int mtyp = msg_type(hdr); 1385 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr); 1386 1387 if (link_is_up(l)) 1388 return; 1389 1390 if (msg_user(hdr) == BCAST_PROTOCOL) { 1391 l->rcv_nxt = peers_snd_nxt; 1392 l->state = LINK_ESTABLISHED; 1393 return; 1394 } 1395 1396 if (l->peer_caps & TIPC_BCAST_SYNCH) 1397 return; 1398 1399 if (msg_peer_node_is_up(hdr)) 1400 return; 1401 1402 /* Compatibility: accept older, less safe initial synch data */ 1403 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG)) 1404 l->rcv_nxt = peers_snd_nxt; 1405 } 1406 1407 /* tipc_link_bc_sync_rcv - update rcv link according to peer's send state 1408 */ 1409 void tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr, 1410 struct sk_buff_head *xmitq) 1411 { 1412 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr); 1413 1414 if (!link_is_up(l)) 1415 return; 1416 1417 if (!msg_peer_node_is_up(hdr)) 1418 return; 1419 1420 l->bc_peer_is_up = true; 1421 1422 /* Ignore if peers_snd_nxt goes beyond receive window */ 1423 if (more(peers_snd_nxt, l->rcv_nxt + l->window)) 1424 return; 1425 1426 if (!more(peers_snd_nxt, l->rcv_nxt)) { 1427 l->nack_state = BC_NACK_SND_CONDITIONAL; 1428 return; 1429 } 1430 1431 /* Don't NACK if one was recently sent or peeked */ 1432 if (l->nack_state == BC_NACK_SND_SUPPRESS) { 1433 l->nack_state = BC_NACK_SND_UNCONDITIONAL; 1434 return; 1435 } 1436 1437 /* Conditionally delay NACK sending until next synch rcv */ 1438 if (l->nack_state == BC_NACK_SND_CONDITIONAL) { 1439 l->nack_state = BC_NACK_SND_UNCONDITIONAL; 1440 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN) 1441 return; 1442 } 1443 1444 /* Send NACK now but suppress next one */ 1445 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq); 1446 l->nack_state = BC_NACK_SND_SUPPRESS; 1447 } 1448 1449 void tipc_link_bc_ack_rcv(struct tipc_link *l, u16 acked, 1450 struct sk_buff_head *xmitq) 1451 { 1452 struct sk_buff *skb, *tmp; 1453 struct tipc_link *snd_l = l->bc_sndlink; 1454 1455 if (!link_is_up(l) || !l->bc_peer_is_up) 1456 return; 1457 1458 if (!more(acked, l->acked)) 1459 return; 1460 1461 /* Skip over packets peer has already acked */ 1462 skb_queue_walk(&snd_l->transmq, skb) { 1463 if (more(buf_seqno(skb), l->acked)) 1464 break; 1465 } 1466 1467 /* Update/release the packets peer is acking now */ 1468 skb_queue_walk_from_safe(&snd_l->transmq, skb, tmp) { 1469 if (more(buf_seqno(skb), acked)) 1470 break; 1471 if (!--TIPC_SKB_CB(skb)->ackers) { 1472 __skb_unlink(skb, &snd_l->transmq); 1473 kfree_skb(skb); 1474 } 1475 } 1476 l->acked = acked; 1477 tipc_link_advance_backlog(snd_l, xmitq); 1478 if (unlikely(!skb_queue_empty(&snd_l->wakeupq))) 1479 link_prepare_wakeup(snd_l); 1480 } 1481 1482 /* tipc_link_bc_nack_rcv(): receive broadcast nack message 1483 */ 1484 int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb, 1485 struct sk_buff_head *xmitq) 1486 { 1487 struct tipc_msg *hdr = buf_msg(skb); 1488 u32 dnode = msg_destnode(hdr); 1489 int mtyp = msg_type(hdr); 1490 u16 acked = msg_bcast_ack(hdr); 1491 u16 from = acked + 1; 1492 u16 to = msg_bcgap_to(hdr); 1493 u16 peers_snd_nxt = to + 1; 1494 int rc = 0; 1495 1496 kfree_skb(skb); 1497 1498 if (!tipc_link_is_up(l) || !l->bc_peer_is_up) 1499 return 0; 1500 1501 if (mtyp != STATE_MSG) 1502 return 0; 1503 1504 if (dnode == link_own_addr(l)) { 1505 tipc_link_bc_ack_rcv(l, acked, xmitq); 1506 rc = tipc_link_retrans(l->bc_sndlink, from, to, xmitq); 1507 l->stats.recv_nacks++; 1508 return rc; 1509 } 1510 1511 /* Msg for other node => suppress own NACK at next sync if applicable */ 1512 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from)) 1513 l->nack_state = BC_NACK_SND_SUPPRESS; 1514 1515 return 0; 1516 } 1517 1518 void tipc_link_set_queue_limits(struct tipc_link *l, u32 win) 1519 { 1520 int max_bulk = TIPC_MAX_PUBLICATIONS / (l->mtu / ITEM_SIZE); 1521 1522 l->window = win; 1523 l->backlog[TIPC_LOW_IMPORTANCE].limit = win / 2; 1524 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = win; 1525 l->backlog[TIPC_HIGH_IMPORTANCE].limit = win / 2 * 3; 1526 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = win * 2; 1527 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk; 1528 } 1529 1530 /* tipc_link_find_owner - locate owner node of link by link's name 1531 * @net: the applicable net namespace 1532 * @name: pointer to link name string 1533 * @bearer_id: pointer to index in 'node->links' array where the link was found. 1534 * 1535 * Returns pointer to node owning the link, or 0 if no matching link is found. 1536 */ 1537 static struct tipc_node *tipc_link_find_owner(struct net *net, 1538 const char *link_name, 1539 unsigned int *bearer_id) 1540 { 1541 struct tipc_net *tn = net_generic(net, tipc_net_id); 1542 struct tipc_link *l_ptr; 1543 struct tipc_node *n_ptr; 1544 struct tipc_node *found_node = NULL; 1545 int i; 1546 1547 *bearer_id = 0; 1548 rcu_read_lock(); 1549 list_for_each_entry_rcu(n_ptr, &tn->node_list, list) { 1550 tipc_node_lock(n_ptr); 1551 for (i = 0; i < MAX_BEARERS; i++) { 1552 l_ptr = n_ptr->links[i].link; 1553 if (l_ptr && !strcmp(l_ptr->name, link_name)) { 1554 *bearer_id = i; 1555 found_node = n_ptr; 1556 break; 1557 } 1558 } 1559 tipc_node_unlock(n_ptr); 1560 if (found_node) 1561 break; 1562 } 1563 rcu_read_unlock(); 1564 1565 return found_node; 1566 } 1567 1568 /** 1569 * link_reset_statistics - reset link statistics 1570 * @l_ptr: pointer to link 1571 */ 1572 static void link_reset_statistics(struct tipc_link *l_ptr) 1573 { 1574 memset(&l_ptr->stats, 0, sizeof(l_ptr->stats)); 1575 l_ptr->stats.sent_info = l_ptr->snd_nxt; 1576 l_ptr->stats.recv_info = l_ptr->rcv_nxt; 1577 } 1578 1579 static void link_print(struct tipc_link *l, const char *str) 1580 { 1581 struct sk_buff *hskb = skb_peek(&l->transmq); 1582 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1; 1583 u16 tail = l->snd_nxt - 1; 1584 1585 pr_info("%s Link <%s> state %x\n", str, l->name, l->state); 1586 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n", 1587 skb_queue_len(&l->transmq), head, tail, 1588 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt); 1589 } 1590 1591 /* Parse and validate nested (link) properties valid for media, bearer and link 1592 */ 1593 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[]) 1594 { 1595 int err; 1596 1597 err = nla_parse_nested(props, TIPC_NLA_PROP_MAX, prop, 1598 tipc_nl_prop_policy); 1599 if (err) 1600 return err; 1601 1602 if (props[TIPC_NLA_PROP_PRIO]) { 1603 u32 prio; 1604 1605 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]); 1606 if (prio > TIPC_MAX_LINK_PRI) 1607 return -EINVAL; 1608 } 1609 1610 if (props[TIPC_NLA_PROP_TOL]) { 1611 u32 tol; 1612 1613 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]); 1614 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL)) 1615 return -EINVAL; 1616 } 1617 1618 if (props[TIPC_NLA_PROP_WIN]) { 1619 u32 win; 1620 1621 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]); 1622 if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN)) 1623 return -EINVAL; 1624 } 1625 1626 return 0; 1627 } 1628 1629 int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info) 1630 { 1631 int err; 1632 int res = 0; 1633 int bearer_id; 1634 char *name; 1635 struct tipc_link *link; 1636 struct tipc_node *node; 1637 struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1]; 1638 struct net *net = sock_net(skb->sk); 1639 1640 if (!info->attrs[TIPC_NLA_LINK]) 1641 return -EINVAL; 1642 1643 err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX, 1644 info->attrs[TIPC_NLA_LINK], 1645 tipc_nl_link_policy); 1646 if (err) 1647 return err; 1648 1649 if (!attrs[TIPC_NLA_LINK_NAME]) 1650 return -EINVAL; 1651 1652 name = nla_data(attrs[TIPC_NLA_LINK_NAME]); 1653 1654 if (strcmp(name, tipc_bclink_name) == 0) 1655 return tipc_nl_bc_link_set(net, attrs); 1656 1657 node = tipc_link_find_owner(net, name, &bearer_id); 1658 if (!node) 1659 return -EINVAL; 1660 1661 tipc_node_lock(node); 1662 1663 link = node->links[bearer_id].link; 1664 if (!link) { 1665 res = -EINVAL; 1666 goto out; 1667 } 1668 1669 if (attrs[TIPC_NLA_LINK_PROP]) { 1670 struct nlattr *props[TIPC_NLA_PROP_MAX + 1]; 1671 1672 err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP], 1673 props); 1674 if (err) { 1675 res = err; 1676 goto out; 1677 } 1678 1679 if (props[TIPC_NLA_PROP_TOL]) { 1680 u32 tol; 1681 1682 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]); 1683 link->tolerance = tol; 1684 tipc_link_proto_xmit(link, STATE_MSG, 0, 0, tol, 0); 1685 } 1686 if (props[TIPC_NLA_PROP_PRIO]) { 1687 u32 prio; 1688 1689 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]); 1690 link->priority = prio; 1691 tipc_link_proto_xmit(link, STATE_MSG, 0, 0, 0, prio); 1692 } 1693 if (props[TIPC_NLA_PROP_WIN]) { 1694 u32 win; 1695 1696 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]); 1697 tipc_link_set_queue_limits(link, win); 1698 } 1699 } 1700 1701 out: 1702 tipc_node_unlock(node); 1703 1704 return res; 1705 } 1706 1707 static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s) 1708 { 1709 int i; 1710 struct nlattr *stats; 1711 1712 struct nla_map { 1713 u32 key; 1714 u32 val; 1715 }; 1716 1717 struct nla_map map[] = { 1718 {TIPC_NLA_STATS_RX_INFO, s->recv_info}, 1719 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments}, 1720 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented}, 1721 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles}, 1722 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled}, 1723 {TIPC_NLA_STATS_TX_INFO, s->sent_info}, 1724 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments}, 1725 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented}, 1726 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles}, 1727 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled}, 1728 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ? 1729 s->msg_length_counts : 1}, 1730 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts}, 1731 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total}, 1732 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]}, 1733 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]}, 1734 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]}, 1735 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]}, 1736 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]}, 1737 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]}, 1738 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]}, 1739 {TIPC_NLA_STATS_RX_STATES, s->recv_states}, 1740 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes}, 1741 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks}, 1742 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv}, 1743 {TIPC_NLA_STATS_TX_STATES, s->sent_states}, 1744 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes}, 1745 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks}, 1746 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks}, 1747 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted}, 1748 {TIPC_NLA_STATS_DUPLICATES, s->duplicates}, 1749 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs}, 1750 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz}, 1751 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ? 1752 (s->accu_queue_sz / s->queue_sz_counts) : 0} 1753 }; 1754 1755 stats = nla_nest_start(skb, TIPC_NLA_LINK_STATS); 1756 if (!stats) 1757 return -EMSGSIZE; 1758 1759 for (i = 0; i < ARRAY_SIZE(map); i++) 1760 if (nla_put_u32(skb, map[i].key, map[i].val)) 1761 goto msg_full; 1762 1763 nla_nest_end(skb, stats); 1764 1765 return 0; 1766 msg_full: 1767 nla_nest_cancel(skb, stats); 1768 1769 return -EMSGSIZE; 1770 } 1771 1772 /* Caller should hold appropriate locks to protect the link */ 1773 static int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg, 1774 struct tipc_link *link, int nlflags) 1775 { 1776 int err; 1777 void *hdr; 1778 struct nlattr *attrs; 1779 struct nlattr *prop; 1780 struct tipc_net *tn = net_generic(net, tipc_net_id); 1781 1782 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family, 1783 nlflags, TIPC_NL_LINK_GET); 1784 if (!hdr) 1785 return -EMSGSIZE; 1786 1787 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK); 1788 if (!attrs) 1789 goto msg_full; 1790 1791 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name)) 1792 goto attr_msg_full; 1793 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, 1794 tipc_cluster_mask(tn->own_addr))) 1795 goto attr_msg_full; 1796 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu)) 1797 goto attr_msg_full; 1798 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->rcv_nxt)) 1799 goto attr_msg_full; 1800 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->snd_nxt)) 1801 goto attr_msg_full; 1802 1803 if (tipc_link_is_up(link)) 1804 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP)) 1805 goto attr_msg_full; 1806 if (link->active) 1807 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE)) 1808 goto attr_msg_full; 1809 1810 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP); 1811 if (!prop) 1812 goto attr_msg_full; 1813 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority)) 1814 goto prop_msg_full; 1815 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance)) 1816 goto prop_msg_full; 1817 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, 1818 link->window)) 1819 goto prop_msg_full; 1820 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority)) 1821 goto prop_msg_full; 1822 nla_nest_end(msg->skb, prop); 1823 1824 err = __tipc_nl_add_stats(msg->skb, &link->stats); 1825 if (err) 1826 goto attr_msg_full; 1827 1828 nla_nest_end(msg->skb, attrs); 1829 genlmsg_end(msg->skb, hdr); 1830 1831 return 0; 1832 1833 prop_msg_full: 1834 nla_nest_cancel(msg->skb, prop); 1835 attr_msg_full: 1836 nla_nest_cancel(msg->skb, attrs); 1837 msg_full: 1838 genlmsg_cancel(msg->skb, hdr); 1839 1840 return -EMSGSIZE; 1841 } 1842 1843 /* Caller should hold node lock */ 1844 static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg, 1845 struct tipc_node *node, u32 *prev_link) 1846 { 1847 u32 i; 1848 int err; 1849 1850 for (i = *prev_link; i < MAX_BEARERS; i++) { 1851 *prev_link = i; 1852 1853 if (!node->links[i].link) 1854 continue; 1855 1856 err = __tipc_nl_add_link(net, msg, 1857 node->links[i].link, NLM_F_MULTI); 1858 if (err) 1859 return err; 1860 } 1861 *prev_link = 0; 1862 1863 return 0; 1864 } 1865 1866 int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb) 1867 { 1868 struct net *net = sock_net(skb->sk); 1869 struct tipc_net *tn = net_generic(net, tipc_net_id); 1870 struct tipc_node *node; 1871 struct tipc_nl_msg msg; 1872 u32 prev_node = cb->args[0]; 1873 u32 prev_link = cb->args[1]; 1874 int done = cb->args[2]; 1875 int err; 1876 1877 if (done) 1878 return 0; 1879 1880 msg.skb = skb; 1881 msg.portid = NETLINK_CB(cb->skb).portid; 1882 msg.seq = cb->nlh->nlmsg_seq; 1883 1884 rcu_read_lock(); 1885 if (prev_node) { 1886 node = tipc_node_find(net, prev_node); 1887 if (!node) { 1888 /* We never set seq or call nl_dump_check_consistent() 1889 * this means that setting prev_seq here will cause the 1890 * consistence check to fail in the netlink callback 1891 * handler. Resulting in the last NLMSG_DONE message 1892 * having the NLM_F_DUMP_INTR flag set. 1893 */ 1894 cb->prev_seq = 1; 1895 goto out; 1896 } 1897 tipc_node_put(node); 1898 1899 list_for_each_entry_continue_rcu(node, &tn->node_list, 1900 list) { 1901 tipc_node_lock(node); 1902 err = __tipc_nl_add_node_links(net, &msg, node, 1903 &prev_link); 1904 tipc_node_unlock(node); 1905 if (err) 1906 goto out; 1907 1908 prev_node = node->addr; 1909 } 1910 } else { 1911 err = tipc_nl_add_bc_link(net, &msg); 1912 if (err) 1913 goto out; 1914 1915 list_for_each_entry_rcu(node, &tn->node_list, list) { 1916 tipc_node_lock(node); 1917 err = __tipc_nl_add_node_links(net, &msg, node, 1918 &prev_link); 1919 tipc_node_unlock(node); 1920 if (err) 1921 goto out; 1922 1923 prev_node = node->addr; 1924 } 1925 } 1926 done = 1; 1927 out: 1928 rcu_read_unlock(); 1929 1930 cb->args[0] = prev_node; 1931 cb->args[1] = prev_link; 1932 cb->args[2] = done; 1933 1934 return skb->len; 1935 } 1936 1937 int tipc_nl_link_get(struct sk_buff *skb, struct genl_info *info) 1938 { 1939 struct net *net = genl_info_net(info); 1940 struct tipc_nl_msg msg; 1941 char *name; 1942 int err; 1943 1944 msg.portid = info->snd_portid; 1945 msg.seq = info->snd_seq; 1946 1947 if (!info->attrs[TIPC_NLA_LINK_NAME]) 1948 return -EINVAL; 1949 name = nla_data(info->attrs[TIPC_NLA_LINK_NAME]); 1950 1951 msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); 1952 if (!msg.skb) 1953 return -ENOMEM; 1954 1955 if (strcmp(name, tipc_bclink_name) == 0) { 1956 err = tipc_nl_add_bc_link(net, &msg); 1957 if (err) { 1958 nlmsg_free(msg.skb); 1959 return err; 1960 } 1961 } else { 1962 int bearer_id; 1963 struct tipc_node *node; 1964 struct tipc_link *link; 1965 1966 node = tipc_link_find_owner(net, name, &bearer_id); 1967 if (!node) 1968 return -EINVAL; 1969 1970 tipc_node_lock(node); 1971 link = node->links[bearer_id].link; 1972 if (!link) { 1973 tipc_node_unlock(node); 1974 nlmsg_free(msg.skb); 1975 return -EINVAL; 1976 } 1977 1978 err = __tipc_nl_add_link(net, &msg, link, 0); 1979 tipc_node_unlock(node); 1980 if (err) { 1981 nlmsg_free(msg.skb); 1982 return err; 1983 } 1984 } 1985 1986 return genlmsg_reply(msg.skb, info); 1987 } 1988 1989 int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info) 1990 { 1991 int err; 1992 char *link_name; 1993 unsigned int bearer_id; 1994 struct tipc_link *link; 1995 struct tipc_node *node; 1996 struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1]; 1997 struct net *net = sock_net(skb->sk); 1998 1999 if (!info->attrs[TIPC_NLA_LINK]) 2000 return -EINVAL; 2001 2002 err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX, 2003 info->attrs[TIPC_NLA_LINK], 2004 tipc_nl_link_policy); 2005 if (err) 2006 return err; 2007 2008 if (!attrs[TIPC_NLA_LINK_NAME]) 2009 return -EINVAL; 2010 2011 link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]); 2012 2013 if (strcmp(link_name, tipc_bclink_name) == 0) { 2014 err = tipc_bclink_reset_stats(net); 2015 if (err) 2016 return err; 2017 return 0; 2018 } 2019 2020 node = tipc_link_find_owner(net, link_name, &bearer_id); 2021 if (!node) 2022 return -EINVAL; 2023 2024 tipc_node_lock(node); 2025 2026 link = node->links[bearer_id].link; 2027 if (!link) { 2028 tipc_node_unlock(node); 2029 return -EINVAL; 2030 } 2031 2032 link_reset_statistics(link); 2033 2034 tipc_node_unlock(node); 2035 2036 return 0; 2037 } 2038