1 /* 2 * net/tipc/bearer.c: TIPC bearer code 3 * 4 * Copyright (c) 1996-2006, Ericsson AB 5 * Copyright (c) 2004-2006, 2010-2011, 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 "config.h" 39 #include "bearer.h" 40 #include "discover.h" 41 42 #define MAX_ADDR_STR 32 43 44 static struct media *media_list[MAX_MEDIA]; 45 static u32 media_count; 46 47 struct tipc_bearer tipc_bearers[MAX_BEARERS]; 48 49 static void bearer_disable(struct tipc_bearer *b_ptr); 50 51 /** 52 * media_name_valid - validate media name 53 * 54 * Returns 1 if media name is valid, otherwise 0. 55 */ 56 57 static int media_name_valid(const char *name) 58 { 59 u32 len; 60 61 len = strlen(name); 62 if ((len + 1) > TIPC_MAX_MEDIA_NAME) 63 return 0; 64 return strspn(name, tipc_alphabet) == len; 65 } 66 67 /** 68 * media_find - locates specified media object by name 69 */ 70 71 static struct media *media_find(const char *name) 72 { 73 u32 i; 74 75 for (i = 0; i < media_count; i++) { 76 if (!strcmp(media_list[i]->name, name)) 77 return media_list[i]; 78 } 79 return NULL; 80 } 81 82 /** 83 * media_find_id - locates specified media object by type identifier 84 */ 85 86 static struct media *media_find_id(u8 type) 87 { 88 u32 i; 89 90 for (i = 0; i < media_count; i++) { 91 if (media_list[i]->type_id == type) 92 return media_list[i]; 93 } 94 return NULL; 95 } 96 97 /** 98 * tipc_register_media - register a media type 99 * 100 * Bearers for this media type must be activated separately at a later stage. 101 */ 102 103 int tipc_register_media(struct media *m_ptr) 104 { 105 int res = -EINVAL; 106 107 write_lock_bh(&tipc_net_lock); 108 109 if (tipc_mode != TIPC_NET_MODE) { 110 warn("Media <%s> rejected, not in networked mode yet\n", 111 m_ptr->name); 112 goto exit; 113 } 114 if (!media_name_valid(m_ptr->name)) { 115 warn("Media <%s> rejected, illegal name\n", m_ptr->name); 116 goto exit; 117 } 118 if (m_ptr->bcast_addr.type != htonl(m_ptr->type_id)) { 119 warn("Media <%s> rejected, illegal broadcast address\n", 120 m_ptr->name); 121 goto exit; 122 } 123 if ((m_ptr->priority < TIPC_MIN_LINK_PRI) || 124 (m_ptr->priority > TIPC_MAX_LINK_PRI)) { 125 warn("Media <%s> rejected, illegal priority (%u)\n", 126 m_ptr->name, m_ptr->priority); 127 goto exit; 128 } 129 if ((m_ptr->tolerance < TIPC_MIN_LINK_TOL) || 130 (m_ptr->tolerance > TIPC_MAX_LINK_TOL)) { 131 warn("Media <%s> rejected, illegal tolerance (%u)\n", 132 m_ptr->name, m_ptr->tolerance); 133 goto exit; 134 } 135 136 if (media_count >= MAX_MEDIA) { 137 warn("Media <%s> rejected, media limit reached (%u)\n", 138 m_ptr->name, MAX_MEDIA); 139 goto exit; 140 } 141 if (media_find(m_ptr->name) || media_find_id(m_ptr->type_id)) { 142 warn("Media <%s> rejected, already registered\n", m_ptr->name); 143 goto exit; 144 } 145 146 media_list[media_count] = m_ptr; 147 media_count++; 148 res = 0; 149 exit: 150 write_unlock_bh(&tipc_net_lock); 151 return res; 152 } 153 154 /** 155 * tipc_media_addr_printf - record media address in print buffer 156 */ 157 158 void tipc_media_addr_printf(struct print_buf *pb, struct tipc_media_addr *a) 159 { 160 struct media *m_ptr; 161 u32 media_type; 162 u32 i; 163 164 media_type = ntohl(a->type); 165 m_ptr = media_find_id(media_type); 166 167 if (m_ptr && (m_ptr->addr2str != NULL)) { 168 char addr_str[MAX_ADDR_STR]; 169 170 tipc_printf(pb, "%s(%s)", m_ptr->name, 171 m_ptr->addr2str(a, addr_str, sizeof(addr_str))); 172 } else { 173 unchar *addr = (unchar *)&a->dev_addr; 174 175 tipc_printf(pb, "UNKNOWN(%u)", media_type); 176 for (i = 0; i < (sizeof(*a) - sizeof(a->type)); i++) 177 tipc_printf(pb, "-%02x", addr[i]); 178 } 179 } 180 181 /** 182 * tipc_media_get_names - record names of registered media in buffer 183 */ 184 185 struct sk_buff *tipc_media_get_names(void) 186 { 187 struct sk_buff *buf; 188 int i; 189 190 buf = tipc_cfg_reply_alloc(MAX_MEDIA * TLV_SPACE(TIPC_MAX_MEDIA_NAME)); 191 if (!buf) 192 return NULL; 193 194 read_lock_bh(&tipc_net_lock); 195 for (i = 0; i < media_count; i++) { 196 tipc_cfg_append_tlv(buf, TIPC_TLV_MEDIA_NAME, 197 media_list[i]->name, 198 strlen(media_list[i]->name) + 1); 199 } 200 read_unlock_bh(&tipc_net_lock); 201 return buf; 202 } 203 204 /** 205 * bearer_name_validate - validate & (optionally) deconstruct bearer name 206 * @name - ptr to bearer name string 207 * @name_parts - ptr to area for bearer name components (or NULL if not needed) 208 * 209 * Returns 1 if bearer name is valid, otherwise 0. 210 */ 211 212 static int bearer_name_validate(const char *name, 213 struct bearer_name *name_parts) 214 { 215 char name_copy[TIPC_MAX_BEARER_NAME]; 216 char *media_name; 217 char *if_name; 218 u32 media_len; 219 u32 if_len; 220 221 /* copy bearer name & ensure length is OK */ 222 223 name_copy[TIPC_MAX_BEARER_NAME - 1] = 0; 224 /* need above in case non-Posix strncpy() doesn't pad with nulls */ 225 strncpy(name_copy, name, TIPC_MAX_BEARER_NAME); 226 if (name_copy[TIPC_MAX_BEARER_NAME - 1] != 0) 227 return 0; 228 229 /* ensure all component parts of bearer name are present */ 230 231 media_name = name_copy; 232 if_name = strchr(media_name, ':'); 233 if (if_name == NULL) 234 return 0; 235 *(if_name++) = 0; 236 media_len = if_name - media_name; 237 if_len = strlen(if_name) + 1; 238 239 /* validate component parts of bearer name */ 240 241 if ((media_len <= 1) || (media_len > TIPC_MAX_MEDIA_NAME) || 242 (if_len <= 1) || (if_len > TIPC_MAX_IF_NAME) || 243 (strspn(media_name, tipc_alphabet) != (media_len - 1)) || 244 (strspn(if_name, tipc_alphabet) != (if_len - 1))) 245 return 0; 246 247 /* return bearer name components, if necessary */ 248 249 if (name_parts) { 250 strcpy(name_parts->media_name, media_name); 251 strcpy(name_parts->if_name, if_name); 252 } 253 return 1; 254 } 255 256 /** 257 * bearer_find - locates bearer object with matching bearer name 258 */ 259 260 static struct tipc_bearer *bearer_find(const char *name) 261 { 262 struct tipc_bearer *b_ptr; 263 u32 i; 264 265 for (i = 0, b_ptr = tipc_bearers; i < MAX_BEARERS; i++, b_ptr++) { 266 if (b_ptr->active && (!strcmp(b_ptr->name, name))) 267 return b_ptr; 268 } 269 return NULL; 270 } 271 272 /** 273 * tipc_bearer_find_interface - locates bearer object with matching interface name 274 */ 275 276 struct tipc_bearer *tipc_bearer_find_interface(const char *if_name) 277 { 278 struct tipc_bearer *b_ptr; 279 char *b_if_name; 280 u32 i; 281 282 for (i = 0, b_ptr = tipc_bearers; i < MAX_BEARERS; i++, b_ptr++) { 283 if (!b_ptr->active) 284 continue; 285 b_if_name = strchr(b_ptr->name, ':') + 1; 286 if (!strcmp(b_if_name, if_name)) 287 return b_ptr; 288 } 289 return NULL; 290 } 291 292 /** 293 * tipc_bearer_get_names - record names of bearers in buffer 294 */ 295 296 struct sk_buff *tipc_bearer_get_names(void) 297 { 298 struct sk_buff *buf; 299 struct tipc_bearer *b_ptr; 300 int i, j; 301 302 buf = tipc_cfg_reply_alloc(MAX_BEARERS * TLV_SPACE(TIPC_MAX_BEARER_NAME)); 303 if (!buf) 304 return NULL; 305 306 read_lock_bh(&tipc_net_lock); 307 for (i = 0; i < media_count; i++) { 308 for (j = 0; j < MAX_BEARERS; j++) { 309 b_ptr = &tipc_bearers[j]; 310 if (b_ptr->active && (b_ptr->media == media_list[i])) { 311 tipc_cfg_append_tlv(buf, TIPC_TLV_BEARER_NAME, 312 b_ptr->name, 313 strlen(b_ptr->name) + 1); 314 } 315 } 316 } 317 read_unlock_bh(&tipc_net_lock); 318 return buf; 319 } 320 321 void tipc_bearer_add_dest(struct tipc_bearer *b_ptr, u32 dest) 322 { 323 tipc_nmap_add(&b_ptr->nodes, dest); 324 tipc_bcbearer_sort(); 325 tipc_disc_add_dest(b_ptr->link_req); 326 } 327 328 void tipc_bearer_remove_dest(struct tipc_bearer *b_ptr, u32 dest) 329 { 330 tipc_nmap_remove(&b_ptr->nodes, dest); 331 tipc_bcbearer_sort(); 332 tipc_disc_remove_dest(b_ptr->link_req); 333 } 334 335 /* 336 * bearer_push(): Resolve bearer congestion. Force the waiting 337 * links to push out their unsent packets, one packet per link 338 * per iteration, until all packets are gone or congestion reoccurs. 339 * 'tipc_net_lock' is read_locked when this function is called 340 * bearer.lock must be taken before calling 341 * Returns binary true(1) ore false(0) 342 */ 343 static int bearer_push(struct tipc_bearer *b_ptr) 344 { 345 u32 res = 0; 346 struct link *ln, *tln; 347 348 if (b_ptr->blocked) 349 return 0; 350 351 while (!list_empty(&b_ptr->cong_links) && (res != PUSH_FAILED)) { 352 list_for_each_entry_safe(ln, tln, &b_ptr->cong_links, link_list) { 353 res = tipc_link_push_packet(ln); 354 if (res == PUSH_FAILED) 355 break; 356 if (res == PUSH_FINISHED) 357 list_move_tail(&ln->link_list, &b_ptr->links); 358 } 359 } 360 return list_empty(&b_ptr->cong_links); 361 } 362 363 void tipc_bearer_lock_push(struct tipc_bearer *b_ptr) 364 { 365 spin_lock_bh(&b_ptr->lock); 366 bearer_push(b_ptr); 367 spin_unlock_bh(&b_ptr->lock); 368 } 369 370 371 /* 372 * Interrupt enabling new requests after bearer congestion or blocking: 373 * See bearer_send(). 374 */ 375 void tipc_continue(struct tipc_bearer *b_ptr) 376 { 377 spin_lock_bh(&b_ptr->lock); 378 if (!list_empty(&b_ptr->cong_links)) 379 tipc_k_signal((Handler)tipc_bearer_lock_push, (unsigned long)b_ptr); 380 b_ptr->blocked = 0; 381 spin_unlock_bh(&b_ptr->lock); 382 } 383 384 /* 385 * Schedule link for sending of messages after the bearer 386 * has been deblocked by 'continue()'. This method is called 387 * when somebody tries to send a message via this link while 388 * the bearer is congested. 'tipc_net_lock' is in read_lock here 389 * bearer.lock is busy 390 */ 391 392 static void tipc_bearer_schedule_unlocked(struct tipc_bearer *b_ptr, struct link *l_ptr) 393 { 394 list_move_tail(&l_ptr->link_list, &b_ptr->cong_links); 395 } 396 397 /* 398 * Schedule link for sending of messages after the bearer 399 * has been deblocked by 'continue()'. This method is called 400 * when somebody tries to send a message via this link while 401 * the bearer is congested. 'tipc_net_lock' is in read_lock here, 402 * bearer.lock is free 403 */ 404 405 void tipc_bearer_schedule(struct tipc_bearer *b_ptr, struct link *l_ptr) 406 { 407 spin_lock_bh(&b_ptr->lock); 408 tipc_bearer_schedule_unlocked(b_ptr, l_ptr); 409 spin_unlock_bh(&b_ptr->lock); 410 } 411 412 413 /* 414 * tipc_bearer_resolve_congestion(): Check if there is bearer congestion, 415 * and if there is, try to resolve it before returning. 416 * 'tipc_net_lock' is read_locked when this function is called 417 */ 418 int tipc_bearer_resolve_congestion(struct tipc_bearer *b_ptr, struct link *l_ptr) 419 { 420 int res = 1; 421 422 if (list_empty(&b_ptr->cong_links)) 423 return 1; 424 spin_lock_bh(&b_ptr->lock); 425 if (!bearer_push(b_ptr)) { 426 tipc_bearer_schedule_unlocked(b_ptr, l_ptr); 427 res = 0; 428 } 429 spin_unlock_bh(&b_ptr->lock); 430 return res; 431 } 432 433 /** 434 * tipc_bearer_congested - determines if bearer is currently congested 435 */ 436 437 int tipc_bearer_congested(struct tipc_bearer *b_ptr, struct link *l_ptr) 438 { 439 if (unlikely(b_ptr->blocked)) 440 return 1; 441 if (likely(list_empty(&b_ptr->cong_links))) 442 return 0; 443 return !tipc_bearer_resolve_congestion(b_ptr, l_ptr); 444 } 445 446 /** 447 * tipc_enable_bearer - enable bearer with the given name 448 */ 449 450 int tipc_enable_bearer(const char *name, u32 disc_domain, u32 priority) 451 { 452 struct tipc_bearer *b_ptr; 453 struct media *m_ptr; 454 struct bearer_name b_name; 455 char addr_string[16]; 456 u32 bearer_id; 457 u32 with_this_prio; 458 u32 i; 459 int res = -EINVAL; 460 461 if (tipc_mode != TIPC_NET_MODE) { 462 warn("Bearer <%s> rejected, not supported in standalone mode\n", 463 name); 464 return -ENOPROTOOPT; 465 } 466 if (!bearer_name_validate(name, &b_name)) { 467 warn("Bearer <%s> rejected, illegal name\n", name); 468 return -EINVAL; 469 } 470 if (tipc_addr_domain_valid(disc_domain) && 471 (disc_domain != tipc_own_addr)) { 472 if (tipc_in_scope(disc_domain, tipc_own_addr)) { 473 disc_domain = tipc_own_addr & TIPC_CLUSTER_MASK; 474 res = 0; /* accept any node in own cluster */ 475 } else if (in_own_cluster(disc_domain)) 476 res = 0; /* accept specified node in own cluster */ 477 } 478 if (res) { 479 warn("Bearer <%s> rejected, illegal discovery domain\n", name); 480 return -EINVAL; 481 } 482 if ((priority < TIPC_MIN_LINK_PRI || 483 priority > TIPC_MAX_LINK_PRI) && 484 (priority != TIPC_MEDIA_LINK_PRI)) { 485 warn("Bearer <%s> rejected, illegal priority\n", name); 486 return -EINVAL; 487 } 488 489 write_lock_bh(&tipc_net_lock); 490 491 m_ptr = media_find(b_name.media_name); 492 if (!m_ptr) { 493 warn("Bearer <%s> rejected, media <%s> not registered\n", name, 494 b_name.media_name); 495 goto exit; 496 } 497 498 if (priority == TIPC_MEDIA_LINK_PRI) 499 priority = m_ptr->priority; 500 501 restart: 502 bearer_id = MAX_BEARERS; 503 with_this_prio = 1; 504 for (i = MAX_BEARERS; i-- != 0; ) { 505 if (!tipc_bearers[i].active) { 506 bearer_id = i; 507 continue; 508 } 509 if (!strcmp(name, tipc_bearers[i].name)) { 510 warn("Bearer <%s> rejected, already enabled\n", name); 511 goto exit; 512 } 513 if ((tipc_bearers[i].priority == priority) && 514 (++with_this_prio > 2)) { 515 if (priority-- == 0) { 516 warn("Bearer <%s> rejected, duplicate priority\n", 517 name); 518 goto exit; 519 } 520 warn("Bearer <%s> priority adjustment required %u->%u\n", 521 name, priority + 1, priority); 522 goto restart; 523 } 524 } 525 if (bearer_id >= MAX_BEARERS) { 526 warn("Bearer <%s> rejected, bearer limit reached (%u)\n", 527 name, MAX_BEARERS); 528 goto exit; 529 } 530 531 b_ptr = &tipc_bearers[bearer_id]; 532 strcpy(b_ptr->name, name); 533 res = m_ptr->enable_bearer(b_ptr); 534 if (res) { 535 warn("Bearer <%s> rejected, enable failure (%d)\n", name, -res); 536 goto exit; 537 } 538 539 b_ptr->identity = bearer_id; 540 b_ptr->media = m_ptr; 541 b_ptr->net_plane = bearer_id + 'A'; 542 b_ptr->active = 1; 543 b_ptr->priority = priority; 544 INIT_LIST_HEAD(&b_ptr->cong_links); 545 INIT_LIST_HEAD(&b_ptr->links); 546 spin_lock_init(&b_ptr->lock); 547 548 res = tipc_disc_create(b_ptr, &m_ptr->bcast_addr, disc_domain); 549 if (res) { 550 bearer_disable(b_ptr); 551 warn("Bearer <%s> rejected, discovery object creation failed\n", 552 name); 553 goto exit; 554 } 555 info("Enabled bearer <%s>, discovery domain %s, priority %u\n", 556 name, tipc_addr_string_fill(addr_string, disc_domain), priority); 557 exit: 558 write_unlock_bh(&tipc_net_lock); 559 return res; 560 } 561 562 /** 563 * tipc_block_bearer(): Block the bearer with the given name, 564 * and reset all its links 565 */ 566 567 int tipc_block_bearer(const char *name) 568 { 569 struct tipc_bearer *b_ptr = NULL; 570 struct link *l_ptr; 571 struct link *temp_l_ptr; 572 573 read_lock_bh(&tipc_net_lock); 574 b_ptr = bearer_find(name); 575 if (!b_ptr) { 576 warn("Attempt to block unknown bearer <%s>\n", name); 577 read_unlock_bh(&tipc_net_lock); 578 return -EINVAL; 579 } 580 581 info("Blocking bearer <%s>\n", name); 582 spin_lock_bh(&b_ptr->lock); 583 b_ptr->blocked = 1; 584 list_splice_init(&b_ptr->cong_links, &b_ptr->links); 585 list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) { 586 struct tipc_node *n_ptr = l_ptr->owner; 587 588 spin_lock_bh(&n_ptr->lock); 589 tipc_link_reset(l_ptr); 590 spin_unlock_bh(&n_ptr->lock); 591 } 592 spin_unlock_bh(&b_ptr->lock); 593 read_unlock_bh(&tipc_net_lock); 594 return 0; 595 } 596 597 /** 598 * bearer_disable - 599 * 600 * Note: This routine assumes caller holds tipc_net_lock. 601 */ 602 603 static void bearer_disable(struct tipc_bearer *b_ptr) 604 { 605 struct link *l_ptr; 606 struct link *temp_l_ptr; 607 608 info("Disabling bearer <%s>\n", b_ptr->name); 609 spin_lock_bh(&b_ptr->lock); 610 b_ptr->blocked = 1; 611 b_ptr->media->disable_bearer(b_ptr); 612 list_splice_init(&b_ptr->cong_links, &b_ptr->links); 613 list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) { 614 tipc_link_delete(l_ptr); 615 } 616 if (b_ptr->link_req) 617 tipc_disc_delete(b_ptr->link_req); 618 spin_unlock_bh(&b_ptr->lock); 619 memset(b_ptr, 0, sizeof(struct tipc_bearer)); 620 } 621 622 int tipc_disable_bearer(const char *name) 623 { 624 struct tipc_bearer *b_ptr; 625 int res; 626 627 write_lock_bh(&tipc_net_lock); 628 b_ptr = bearer_find(name); 629 if (b_ptr == NULL) { 630 warn("Attempt to disable unknown bearer <%s>\n", name); 631 res = -EINVAL; 632 } else { 633 bearer_disable(b_ptr); 634 res = 0; 635 } 636 write_unlock_bh(&tipc_net_lock); 637 return res; 638 } 639 640 641 642 void tipc_bearer_stop(void) 643 { 644 u32 i; 645 646 for (i = 0; i < MAX_BEARERS; i++) { 647 if (tipc_bearers[i].active) 648 bearer_disable(&tipc_bearers[i]); 649 } 650 media_count = 0; 651 } 652