1 /* 2 * net/tipc/node.c: TIPC node management routines 3 * 4 * Copyright (c) 2000-2006, 2012-2014, 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 "config.h" 39 #include "node.h" 40 #include "name_distr.h" 41 #include "socket.h" 42 43 #define NODE_HTABLE_SIZE 512 44 45 static void node_lost_contact(struct tipc_node *n_ptr); 46 static void node_established_contact(struct tipc_node *n_ptr); 47 48 static struct hlist_head node_htable[NODE_HTABLE_SIZE]; 49 LIST_HEAD(tipc_node_list); 50 static u32 tipc_num_nodes; 51 static u32 tipc_num_links; 52 static DEFINE_SPINLOCK(node_list_lock); 53 54 struct tipc_sock_conn { 55 u32 port; 56 u32 peer_port; 57 u32 peer_node; 58 struct list_head list; 59 }; 60 61 /* 62 * A trivial power-of-two bitmask technique is used for speed, since this 63 * operation is done for every incoming TIPC packet. The number of hash table 64 * entries has been chosen so that no hash chain exceeds 8 nodes and will 65 * usually be much smaller (typically only a single node). 66 */ 67 static unsigned int tipc_hashfn(u32 addr) 68 { 69 return addr & (NODE_HTABLE_SIZE - 1); 70 } 71 72 /* 73 * tipc_node_find - locate specified node object, if it exists 74 */ 75 struct tipc_node *tipc_node_find(u32 addr) 76 { 77 struct tipc_node *node; 78 79 if (unlikely(!in_own_cluster_exact(addr))) 80 return NULL; 81 82 rcu_read_lock(); 83 hlist_for_each_entry_rcu(node, &node_htable[tipc_hashfn(addr)], hash) { 84 if (node->addr == addr) { 85 rcu_read_unlock(); 86 return node; 87 } 88 } 89 rcu_read_unlock(); 90 return NULL; 91 } 92 93 struct tipc_node *tipc_node_create(u32 addr) 94 { 95 struct tipc_node *n_ptr, *temp_node; 96 97 spin_lock_bh(&node_list_lock); 98 99 n_ptr = kzalloc(sizeof(*n_ptr), GFP_ATOMIC); 100 if (!n_ptr) { 101 spin_unlock_bh(&node_list_lock); 102 pr_warn("Node creation failed, no memory\n"); 103 return NULL; 104 } 105 106 n_ptr->addr = addr; 107 spin_lock_init(&n_ptr->lock); 108 INIT_HLIST_NODE(&n_ptr->hash); 109 INIT_LIST_HEAD(&n_ptr->list); 110 INIT_LIST_HEAD(&n_ptr->nsub); 111 INIT_LIST_HEAD(&n_ptr->conn_sks); 112 __skb_queue_head_init(&n_ptr->waiting_sks); 113 114 hlist_add_head_rcu(&n_ptr->hash, &node_htable[tipc_hashfn(addr)]); 115 116 list_for_each_entry_rcu(temp_node, &tipc_node_list, list) { 117 if (n_ptr->addr < temp_node->addr) 118 break; 119 } 120 list_add_tail_rcu(&n_ptr->list, &temp_node->list); 121 n_ptr->action_flags = TIPC_WAIT_PEER_LINKS_DOWN; 122 n_ptr->signature = INVALID_NODE_SIG; 123 124 tipc_num_nodes++; 125 126 spin_unlock_bh(&node_list_lock); 127 return n_ptr; 128 } 129 130 static void tipc_node_delete(struct tipc_node *n_ptr) 131 { 132 list_del_rcu(&n_ptr->list); 133 hlist_del_rcu(&n_ptr->hash); 134 kfree_rcu(n_ptr, rcu); 135 136 tipc_num_nodes--; 137 } 138 139 void tipc_node_stop(void) 140 { 141 struct tipc_node *node, *t_node; 142 143 spin_lock_bh(&node_list_lock); 144 list_for_each_entry_safe(node, t_node, &tipc_node_list, list) 145 tipc_node_delete(node); 146 spin_unlock_bh(&node_list_lock); 147 } 148 149 int tipc_node_add_conn(u32 dnode, u32 port, u32 peer_port) 150 { 151 struct tipc_node *node; 152 struct tipc_sock_conn *conn; 153 154 if (in_own_node(dnode)) 155 return 0; 156 157 node = tipc_node_find(dnode); 158 if (!node) { 159 pr_warn("Connecting sock to node 0x%x failed\n", dnode); 160 return -EHOSTUNREACH; 161 } 162 conn = kmalloc(sizeof(*conn), GFP_ATOMIC); 163 if (!conn) 164 return -EHOSTUNREACH; 165 conn->peer_node = dnode; 166 conn->port = port; 167 conn->peer_port = peer_port; 168 169 tipc_node_lock(node); 170 list_add_tail(&conn->list, &node->conn_sks); 171 tipc_node_unlock(node); 172 return 0; 173 } 174 175 void tipc_node_remove_conn(u32 dnode, u32 port) 176 { 177 struct tipc_node *node; 178 struct tipc_sock_conn *conn, *safe; 179 180 if (in_own_node(dnode)) 181 return; 182 183 node = tipc_node_find(dnode); 184 if (!node) 185 return; 186 187 tipc_node_lock(node); 188 list_for_each_entry_safe(conn, safe, &node->conn_sks, list) { 189 if (port != conn->port) 190 continue; 191 list_del(&conn->list); 192 kfree(conn); 193 } 194 tipc_node_unlock(node); 195 } 196 197 void tipc_node_abort_sock_conns(struct list_head *conns) 198 { 199 struct tipc_sock_conn *conn, *safe; 200 struct sk_buff *buf; 201 202 list_for_each_entry_safe(conn, safe, conns, list) { 203 buf = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE, TIPC_CONN_MSG, 204 SHORT_H_SIZE, 0, tipc_own_addr, 205 conn->peer_node, conn->port, 206 conn->peer_port, TIPC_ERR_NO_NODE); 207 if (likely(buf)) 208 tipc_sk_rcv(buf); 209 list_del(&conn->list); 210 kfree(conn); 211 } 212 } 213 214 /** 215 * tipc_node_link_up - handle addition of link 216 * 217 * Link becomes active (alone or shared) or standby, depending on its priority. 218 */ 219 void tipc_node_link_up(struct tipc_node *n_ptr, struct tipc_link *l_ptr) 220 { 221 struct tipc_link **active = &n_ptr->active_links[0]; 222 u32 addr = n_ptr->addr; 223 224 n_ptr->working_links++; 225 tipc_nametbl_publish(TIPC_LINK_STATE, addr, addr, TIPC_NODE_SCOPE, 226 l_ptr->bearer_id, addr); 227 pr_info("Established link <%s> on network plane %c\n", 228 l_ptr->name, l_ptr->net_plane); 229 230 if (!active[0]) { 231 active[0] = active[1] = l_ptr; 232 node_established_contact(n_ptr); 233 goto exit; 234 } 235 if (l_ptr->priority < active[0]->priority) { 236 pr_info("New link <%s> becomes standby\n", l_ptr->name); 237 goto exit; 238 } 239 tipc_link_dup_queue_xmit(active[0], l_ptr); 240 if (l_ptr->priority == active[0]->priority) { 241 active[0] = l_ptr; 242 goto exit; 243 } 244 pr_info("Old link <%s> becomes standby\n", active[0]->name); 245 if (active[1] != active[0]) 246 pr_info("Old link <%s> becomes standby\n", active[1]->name); 247 active[0] = active[1] = l_ptr; 248 exit: 249 /* Leave room for changeover header when returning 'mtu' to users: */ 250 n_ptr->act_mtus[0] = active[0]->max_pkt - INT_H_SIZE; 251 n_ptr->act_mtus[1] = active[1]->max_pkt - INT_H_SIZE; 252 } 253 254 /** 255 * node_select_active_links - select active link 256 */ 257 static void node_select_active_links(struct tipc_node *n_ptr) 258 { 259 struct tipc_link **active = &n_ptr->active_links[0]; 260 u32 i; 261 u32 highest_prio = 0; 262 263 active[0] = active[1] = NULL; 264 265 for (i = 0; i < MAX_BEARERS; i++) { 266 struct tipc_link *l_ptr = n_ptr->links[i]; 267 268 if (!l_ptr || !tipc_link_is_up(l_ptr) || 269 (l_ptr->priority < highest_prio)) 270 continue; 271 272 if (l_ptr->priority > highest_prio) { 273 highest_prio = l_ptr->priority; 274 active[0] = active[1] = l_ptr; 275 } else { 276 active[1] = l_ptr; 277 } 278 } 279 } 280 281 /** 282 * tipc_node_link_down - handle loss of link 283 */ 284 void tipc_node_link_down(struct tipc_node *n_ptr, struct tipc_link *l_ptr) 285 { 286 struct tipc_link **active; 287 u32 addr = n_ptr->addr; 288 289 n_ptr->working_links--; 290 tipc_nametbl_withdraw(TIPC_LINK_STATE, addr, l_ptr->bearer_id, addr); 291 292 if (!tipc_link_is_active(l_ptr)) { 293 pr_info("Lost standby link <%s> on network plane %c\n", 294 l_ptr->name, l_ptr->net_plane); 295 return; 296 } 297 pr_info("Lost link <%s> on network plane %c\n", 298 l_ptr->name, l_ptr->net_plane); 299 300 active = &n_ptr->active_links[0]; 301 if (active[0] == l_ptr) 302 active[0] = active[1]; 303 if (active[1] == l_ptr) 304 active[1] = active[0]; 305 if (active[0] == l_ptr) 306 node_select_active_links(n_ptr); 307 if (tipc_node_is_up(n_ptr)) 308 tipc_link_failover_send_queue(l_ptr); 309 else 310 node_lost_contact(n_ptr); 311 312 /* Leave room for changeover header when returning 'mtu' to users: */ 313 if (active[0]) { 314 n_ptr->act_mtus[0] = active[0]->max_pkt - INT_H_SIZE; 315 n_ptr->act_mtus[1] = active[1]->max_pkt - INT_H_SIZE; 316 return; 317 } 318 319 /* Loopback link went down? No fragmentation needed from now on. */ 320 if (n_ptr->addr == tipc_own_addr) { 321 n_ptr->act_mtus[0] = MAX_MSG_SIZE; 322 n_ptr->act_mtus[1] = MAX_MSG_SIZE; 323 } 324 } 325 326 int tipc_node_active_links(struct tipc_node *n_ptr) 327 { 328 return n_ptr->active_links[0] != NULL; 329 } 330 331 int tipc_node_is_up(struct tipc_node *n_ptr) 332 { 333 return tipc_node_active_links(n_ptr); 334 } 335 336 void tipc_node_attach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr) 337 { 338 n_ptr->links[l_ptr->bearer_id] = l_ptr; 339 spin_lock_bh(&node_list_lock); 340 tipc_num_links++; 341 spin_unlock_bh(&node_list_lock); 342 n_ptr->link_cnt++; 343 } 344 345 void tipc_node_detach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr) 346 { 347 int i; 348 349 for (i = 0; i < MAX_BEARERS; i++) { 350 if (l_ptr != n_ptr->links[i]) 351 continue; 352 n_ptr->links[i] = NULL; 353 spin_lock_bh(&node_list_lock); 354 tipc_num_links--; 355 spin_unlock_bh(&node_list_lock); 356 n_ptr->link_cnt--; 357 } 358 } 359 360 static void node_established_contact(struct tipc_node *n_ptr) 361 { 362 n_ptr->action_flags |= TIPC_NOTIFY_NODE_UP; 363 n_ptr->bclink.oos_state = 0; 364 n_ptr->bclink.acked = tipc_bclink_get_last_sent(); 365 tipc_bclink_add_node(n_ptr->addr); 366 } 367 368 static void node_lost_contact(struct tipc_node *n_ptr) 369 { 370 char addr_string[16]; 371 u32 i; 372 373 pr_info("Lost contact with %s\n", 374 tipc_addr_string_fill(addr_string, n_ptr->addr)); 375 376 /* Flush broadcast link info associated with lost node */ 377 if (n_ptr->bclink.recv_permitted) { 378 kfree_skb_list(n_ptr->bclink.deferred_head); 379 n_ptr->bclink.deferred_size = 0; 380 381 if (n_ptr->bclink.reasm_buf) { 382 kfree_skb(n_ptr->bclink.reasm_buf); 383 n_ptr->bclink.reasm_buf = NULL; 384 } 385 386 tipc_bclink_remove_node(n_ptr->addr); 387 tipc_bclink_acknowledge(n_ptr, INVALID_LINK_SEQ); 388 389 n_ptr->bclink.recv_permitted = false; 390 } 391 392 /* Abort link changeover */ 393 for (i = 0; i < MAX_BEARERS; i++) { 394 struct tipc_link *l_ptr = n_ptr->links[i]; 395 if (!l_ptr) 396 continue; 397 l_ptr->reset_checkpoint = l_ptr->next_in_no; 398 l_ptr->exp_msg_count = 0; 399 tipc_link_reset_fragments(l_ptr); 400 } 401 402 n_ptr->action_flags &= ~TIPC_WAIT_OWN_LINKS_DOWN; 403 404 /* Notify subscribers and prevent re-contact with node until 405 * cleanup is done. 406 */ 407 n_ptr->action_flags |= TIPC_WAIT_PEER_LINKS_DOWN | 408 TIPC_NOTIFY_NODE_DOWN; 409 } 410 411 struct sk_buff *tipc_node_get_nodes(const void *req_tlv_area, int req_tlv_space) 412 { 413 u32 domain; 414 struct sk_buff *buf; 415 struct tipc_node *n_ptr; 416 struct tipc_node_info node_info; 417 u32 payload_size; 418 419 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR)) 420 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR); 421 422 domain = ntohl(*(__be32 *)TLV_DATA(req_tlv_area)); 423 if (!tipc_addr_domain_valid(domain)) 424 return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE 425 " (network address)"); 426 427 spin_lock_bh(&node_list_lock); 428 if (!tipc_num_nodes) { 429 spin_unlock_bh(&node_list_lock); 430 return tipc_cfg_reply_none(); 431 } 432 433 /* For now, get space for all other nodes */ 434 payload_size = TLV_SPACE(sizeof(node_info)) * tipc_num_nodes; 435 if (payload_size > 32768u) { 436 spin_unlock_bh(&node_list_lock); 437 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED 438 " (too many nodes)"); 439 } 440 spin_unlock_bh(&node_list_lock); 441 442 buf = tipc_cfg_reply_alloc(payload_size); 443 if (!buf) 444 return NULL; 445 446 /* Add TLVs for all nodes in scope */ 447 rcu_read_lock(); 448 list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) { 449 if (!tipc_in_scope(domain, n_ptr->addr)) 450 continue; 451 node_info.addr = htonl(n_ptr->addr); 452 node_info.up = htonl(tipc_node_is_up(n_ptr)); 453 tipc_cfg_append_tlv(buf, TIPC_TLV_NODE_INFO, 454 &node_info, sizeof(node_info)); 455 } 456 rcu_read_unlock(); 457 return buf; 458 } 459 460 struct sk_buff *tipc_node_get_links(const void *req_tlv_area, int req_tlv_space) 461 { 462 u32 domain; 463 struct sk_buff *buf; 464 struct tipc_node *n_ptr; 465 struct tipc_link_info link_info; 466 u32 payload_size; 467 468 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR)) 469 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR); 470 471 domain = ntohl(*(__be32 *)TLV_DATA(req_tlv_area)); 472 if (!tipc_addr_domain_valid(domain)) 473 return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE 474 " (network address)"); 475 476 if (!tipc_own_addr) 477 return tipc_cfg_reply_none(); 478 479 spin_lock_bh(&node_list_lock); 480 /* Get space for all unicast links + broadcast link */ 481 payload_size = TLV_SPACE((sizeof(link_info)) * (tipc_num_links + 1)); 482 if (payload_size > 32768u) { 483 spin_unlock_bh(&node_list_lock); 484 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED 485 " (too many links)"); 486 } 487 spin_unlock_bh(&node_list_lock); 488 489 buf = tipc_cfg_reply_alloc(payload_size); 490 if (!buf) 491 return NULL; 492 493 /* Add TLV for broadcast link */ 494 link_info.dest = htonl(tipc_cluster_mask(tipc_own_addr)); 495 link_info.up = htonl(1); 496 strlcpy(link_info.str, tipc_bclink_name, TIPC_MAX_LINK_NAME); 497 tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO, &link_info, sizeof(link_info)); 498 499 /* Add TLVs for any other links in scope */ 500 rcu_read_lock(); 501 list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) { 502 u32 i; 503 504 if (!tipc_in_scope(domain, n_ptr->addr)) 505 continue; 506 tipc_node_lock(n_ptr); 507 for (i = 0; i < MAX_BEARERS; i++) { 508 if (!n_ptr->links[i]) 509 continue; 510 link_info.dest = htonl(n_ptr->addr); 511 link_info.up = htonl(tipc_link_is_up(n_ptr->links[i])); 512 strcpy(link_info.str, n_ptr->links[i]->name); 513 tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO, 514 &link_info, sizeof(link_info)); 515 } 516 tipc_node_unlock(n_ptr); 517 } 518 rcu_read_unlock(); 519 return buf; 520 } 521 522 /** 523 * tipc_node_get_linkname - get the name of a link 524 * 525 * @bearer_id: id of the bearer 526 * @node: peer node address 527 * @linkname: link name output buffer 528 * 529 * Returns 0 on success 530 */ 531 int tipc_node_get_linkname(u32 bearer_id, u32 addr, char *linkname, size_t len) 532 { 533 struct tipc_link *link; 534 struct tipc_node *node = tipc_node_find(addr); 535 536 if ((bearer_id >= MAX_BEARERS) || !node) 537 return -EINVAL; 538 tipc_node_lock(node); 539 link = node->links[bearer_id]; 540 if (link) { 541 strncpy(linkname, link->name, len); 542 tipc_node_unlock(node); 543 return 0; 544 } 545 tipc_node_unlock(node); 546 return -EINVAL; 547 } 548 549 void tipc_node_unlock(struct tipc_node *node) 550 { 551 LIST_HEAD(nsub_list); 552 LIST_HEAD(conn_sks); 553 struct sk_buff_head waiting_sks; 554 u32 addr = 0; 555 unsigned int flags = node->action_flags; 556 557 if (likely(!node->action_flags)) { 558 spin_unlock_bh(&node->lock); 559 return; 560 } 561 562 __skb_queue_head_init(&waiting_sks); 563 if (node->action_flags & TIPC_WAKEUP_USERS) { 564 skb_queue_splice_init(&node->waiting_sks, &waiting_sks); 565 node->action_flags &= ~TIPC_WAKEUP_USERS; 566 } 567 if (node->action_flags & TIPC_NOTIFY_NODE_DOWN) { 568 list_replace_init(&node->nsub, &nsub_list); 569 list_replace_init(&node->conn_sks, &conn_sks); 570 node->action_flags &= ~TIPC_NOTIFY_NODE_DOWN; 571 } 572 if (node->action_flags & TIPC_NOTIFY_NODE_UP) { 573 node->action_flags &= ~TIPC_NOTIFY_NODE_UP; 574 addr = node->addr; 575 } 576 node->action_flags &= ~TIPC_WAKEUP_BCAST_USERS; 577 spin_unlock_bh(&node->lock); 578 579 while (!skb_queue_empty(&waiting_sks)) 580 tipc_sk_rcv(__skb_dequeue(&waiting_sks)); 581 582 if (!list_empty(&conn_sks)) 583 tipc_node_abort_sock_conns(&conn_sks); 584 585 if (!list_empty(&nsub_list)) 586 tipc_nodesub_notify(&nsub_list); 587 588 if (flags & TIPC_WAKEUP_BCAST_USERS) 589 tipc_bclink_wakeup_users(); 590 591 if (addr) 592 tipc_named_node_up(addr); 593 } 594