1 /* 2 * net/tipc/name_distr.c: TIPC name distribution code 3 * 4 * Copyright (c) 2000-2006, 2014, Ericsson AB 5 * Copyright (c) 2005, 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 "link.h" 39 #include "name_distr.h" 40 41 int sysctl_tipc_named_timeout __read_mostly = 2000; 42 43 /** 44 * struct tipc_dist_queue - queue holding deferred name table updates 45 */ 46 static struct list_head tipc_dist_queue = LIST_HEAD_INIT(tipc_dist_queue); 47 48 struct distr_queue_item { 49 struct distr_item i; 50 u32 dtype; 51 u32 node; 52 unsigned long expires; 53 struct list_head next; 54 }; 55 56 /** 57 * publ_to_item - add publication info to a publication message 58 */ 59 static void publ_to_item(struct distr_item *i, struct publication *p) 60 { 61 i->type = htonl(p->type); 62 i->lower = htonl(p->lower); 63 i->upper = htonl(p->upper); 64 i->ref = htonl(p->ref); 65 i->key = htonl(p->key); 66 } 67 68 /** 69 * named_prepare_buf - allocate & initialize a publication message 70 */ 71 static struct sk_buff *named_prepare_buf(struct net *net, u32 type, u32 size, 72 u32 dest) 73 { 74 struct tipc_net *tn = net_generic(net, tipc_net_id); 75 struct sk_buff *buf = tipc_buf_acquire(INT_H_SIZE + size); 76 struct tipc_msg *msg; 77 78 if (buf != NULL) { 79 msg = buf_msg(buf); 80 tipc_msg_init(tn->own_addr, msg, NAME_DISTRIBUTOR, type, 81 INT_H_SIZE, dest); 82 msg_set_size(msg, INT_H_SIZE + size); 83 } 84 return buf; 85 } 86 87 void named_cluster_distribute(struct net *net, struct sk_buff *skb) 88 { 89 struct tipc_net *tn = net_generic(net, tipc_net_id); 90 struct sk_buff *oskb; 91 struct tipc_node *node; 92 u32 dnode; 93 94 rcu_read_lock(); 95 list_for_each_entry_rcu(node, &tn->node_list, list) { 96 dnode = node->addr; 97 if (in_own_node(net, dnode)) 98 continue; 99 if (!tipc_node_is_up(node)) 100 continue; 101 oskb = pskb_copy(skb, GFP_ATOMIC); 102 if (!oskb) 103 break; 104 msg_set_destnode(buf_msg(oskb), dnode); 105 tipc_node_xmit_skb(net, oskb, dnode, 0); 106 } 107 rcu_read_unlock(); 108 109 kfree_skb(skb); 110 } 111 112 /** 113 * tipc_named_publish - tell other nodes about a new publication by this node 114 */ 115 struct sk_buff *tipc_named_publish(struct net *net, struct publication *publ) 116 { 117 struct tipc_net *tn = net_generic(net, tipc_net_id); 118 struct sk_buff *buf; 119 struct distr_item *item; 120 121 list_add_tail_rcu(&publ->local_list, 122 &tn->nametbl->publ_list[publ->scope]); 123 124 if (publ->scope == TIPC_NODE_SCOPE) 125 return NULL; 126 127 buf = named_prepare_buf(net, PUBLICATION, ITEM_SIZE, 0); 128 if (!buf) { 129 pr_warn("Publication distribution failure\n"); 130 return NULL; 131 } 132 133 item = (struct distr_item *)msg_data(buf_msg(buf)); 134 publ_to_item(item, publ); 135 return buf; 136 } 137 138 /** 139 * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node 140 */ 141 struct sk_buff *tipc_named_withdraw(struct net *net, struct publication *publ) 142 { 143 struct sk_buff *buf; 144 struct distr_item *item; 145 146 list_del(&publ->local_list); 147 148 if (publ->scope == TIPC_NODE_SCOPE) 149 return NULL; 150 151 buf = named_prepare_buf(net, WITHDRAWAL, ITEM_SIZE, 0); 152 if (!buf) { 153 pr_warn("Withdrawal distribution failure\n"); 154 return NULL; 155 } 156 157 item = (struct distr_item *)msg_data(buf_msg(buf)); 158 publ_to_item(item, publ); 159 return buf; 160 } 161 162 /** 163 * named_distribute - prepare name info for bulk distribution to another node 164 * @list: list of messages (buffers) to be returned from this function 165 * @dnode: node to be updated 166 * @pls: linked list of publication items to be packed into buffer chain 167 */ 168 static void named_distribute(struct net *net, struct sk_buff_head *list, 169 u32 dnode, struct list_head *pls) 170 { 171 struct publication *publ; 172 struct sk_buff *skb = NULL; 173 struct distr_item *item = NULL; 174 uint msg_dsz = (tipc_node_get_mtu(net, dnode, 0) / ITEM_SIZE) * 175 ITEM_SIZE; 176 uint msg_rem = msg_dsz; 177 178 list_for_each_entry(publ, pls, local_list) { 179 /* Prepare next buffer: */ 180 if (!skb) { 181 skb = named_prepare_buf(net, PUBLICATION, msg_rem, 182 dnode); 183 if (!skb) { 184 pr_warn("Bulk publication failure\n"); 185 return; 186 } 187 item = (struct distr_item *)msg_data(buf_msg(skb)); 188 } 189 190 /* Pack publication into message: */ 191 publ_to_item(item, publ); 192 item++; 193 msg_rem -= ITEM_SIZE; 194 195 /* Append full buffer to list: */ 196 if (!msg_rem) { 197 __skb_queue_tail(list, skb); 198 skb = NULL; 199 msg_rem = msg_dsz; 200 } 201 } 202 if (skb) { 203 msg_set_size(buf_msg(skb), INT_H_SIZE + (msg_dsz - msg_rem)); 204 skb_trim(skb, INT_H_SIZE + (msg_dsz - msg_rem)); 205 __skb_queue_tail(list, skb); 206 } 207 } 208 209 /** 210 * tipc_named_node_up - tell specified node about all publications by this node 211 */ 212 void tipc_named_node_up(struct net *net, u32 dnode) 213 { 214 struct tipc_net *tn = net_generic(net, tipc_net_id); 215 struct sk_buff_head head; 216 217 __skb_queue_head_init(&head); 218 219 rcu_read_lock(); 220 named_distribute(net, &head, dnode, 221 &tn->nametbl->publ_list[TIPC_CLUSTER_SCOPE]); 222 named_distribute(net, &head, dnode, 223 &tn->nametbl->publ_list[TIPC_ZONE_SCOPE]); 224 rcu_read_unlock(); 225 226 tipc_node_xmit(net, &head, dnode, 0); 227 } 228 229 static void tipc_publ_subscribe(struct net *net, struct publication *publ, 230 u32 addr) 231 { 232 struct tipc_node *node; 233 234 if (in_own_node(net, addr)) 235 return; 236 237 node = tipc_node_find(net, addr); 238 if (!node) { 239 pr_warn("Node subscription rejected, unknown node 0x%x\n", 240 addr); 241 return; 242 } 243 244 tipc_node_lock(node); 245 list_add_tail(&publ->nodesub_list, &node->publ_list); 246 tipc_node_unlock(node); 247 tipc_node_put(node); 248 } 249 250 static void tipc_publ_unsubscribe(struct net *net, struct publication *publ, 251 u32 addr) 252 { 253 struct tipc_node *node; 254 255 node = tipc_node_find(net, addr); 256 if (!node) 257 return; 258 259 tipc_node_lock(node); 260 list_del_init(&publ->nodesub_list); 261 tipc_node_unlock(node); 262 tipc_node_put(node); 263 } 264 265 /** 266 * tipc_publ_purge - remove publication associated with a failed node 267 * 268 * Invoked for each publication issued by a newly failed node. 269 * Removes publication structure from name table & deletes it. 270 */ 271 static void tipc_publ_purge(struct net *net, struct publication *publ, u32 addr) 272 { 273 struct tipc_net *tn = net_generic(net, tipc_net_id); 274 struct publication *p; 275 276 spin_lock_bh(&tn->nametbl_lock); 277 p = tipc_nametbl_remove_publ(net, publ->type, publ->lower, 278 publ->node, publ->ref, publ->key); 279 if (p) 280 tipc_publ_unsubscribe(net, p, addr); 281 spin_unlock_bh(&tn->nametbl_lock); 282 283 if (p != publ) { 284 pr_err("Unable to remove publication from failed node\n" 285 " (type=%u, lower=%u, node=0x%x, ref=%u, key=%u)\n", 286 publ->type, publ->lower, publ->node, publ->ref, 287 publ->key); 288 } 289 290 kfree_rcu(p, rcu); 291 } 292 293 void tipc_publ_notify(struct net *net, struct list_head *nsub_list, u32 addr) 294 { 295 struct publication *publ, *tmp; 296 297 list_for_each_entry_safe(publ, tmp, nsub_list, nodesub_list) 298 tipc_publ_purge(net, publ, addr); 299 } 300 301 /** 302 * tipc_update_nametbl - try to process a nametable update and notify 303 * subscribers 304 * 305 * tipc_nametbl_lock must be held. 306 * Returns the publication item if successful, otherwise NULL. 307 */ 308 static bool tipc_update_nametbl(struct net *net, struct distr_item *i, 309 u32 node, u32 dtype) 310 { 311 struct publication *publ = NULL; 312 313 if (dtype == PUBLICATION) { 314 publ = tipc_nametbl_insert_publ(net, ntohl(i->type), 315 ntohl(i->lower), 316 ntohl(i->upper), 317 TIPC_CLUSTER_SCOPE, node, 318 ntohl(i->ref), ntohl(i->key)); 319 if (publ) { 320 tipc_publ_subscribe(net, publ, node); 321 return true; 322 } 323 } else if (dtype == WITHDRAWAL) { 324 publ = tipc_nametbl_remove_publ(net, ntohl(i->type), 325 ntohl(i->lower), 326 node, ntohl(i->ref), 327 ntohl(i->key)); 328 if (publ) { 329 tipc_publ_unsubscribe(net, publ, node); 330 kfree_rcu(publ, rcu); 331 return true; 332 } 333 } else { 334 pr_warn("Unrecognized name table message received\n"); 335 } 336 return false; 337 } 338 339 /** 340 * tipc_named_add_backlog - add a failed name table update to the backlog 341 * 342 */ 343 static void tipc_named_add_backlog(struct distr_item *i, u32 type, u32 node) 344 { 345 struct distr_queue_item *e; 346 unsigned long now = get_jiffies_64(); 347 348 e = kzalloc(sizeof(*e), GFP_ATOMIC); 349 if (!e) 350 return; 351 e->dtype = type; 352 e->node = node; 353 e->expires = now + msecs_to_jiffies(sysctl_tipc_named_timeout); 354 memcpy(e, i, sizeof(*i)); 355 list_add_tail(&e->next, &tipc_dist_queue); 356 } 357 358 /** 359 * tipc_named_process_backlog - try to process any pending name table updates 360 * from the network. 361 */ 362 void tipc_named_process_backlog(struct net *net) 363 { 364 struct distr_queue_item *e, *tmp; 365 char addr[16]; 366 unsigned long now = get_jiffies_64(); 367 368 list_for_each_entry_safe(e, tmp, &tipc_dist_queue, next) { 369 if (time_after(e->expires, now)) { 370 if (!tipc_update_nametbl(net, &e->i, e->node, e->dtype)) 371 continue; 372 } else { 373 tipc_addr_string_fill(addr, e->node); 374 pr_warn_ratelimited("Dropping name table update (%d) of {%u, %u, %u} from %s key=%u\n", 375 e->dtype, ntohl(e->i.type), 376 ntohl(e->i.lower), 377 ntohl(e->i.upper), 378 addr, ntohl(e->i.key)); 379 } 380 list_del(&e->next); 381 kfree(e); 382 } 383 } 384 385 /** 386 * tipc_named_rcv - process name table update messages sent by another node 387 */ 388 void tipc_named_rcv(struct net *net, struct sk_buff_head *inputq) 389 { 390 struct tipc_net *tn = net_generic(net, tipc_net_id); 391 struct tipc_msg *msg; 392 struct distr_item *item; 393 uint count; 394 u32 node; 395 struct sk_buff *skb; 396 int mtype; 397 398 spin_lock_bh(&tn->nametbl_lock); 399 for (skb = skb_dequeue(inputq); skb; skb = skb_dequeue(inputq)) { 400 msg = buf_msg(skb); 401 mtype = msg_type(msg); 402 item = (struct distr_item *)msg_data(msg); 403 count = msg_data_sz(msg) / ITEM_SIZE; 404 node = msg_orignode(msg); 405 while (count--) { 406 if (!tipc_update_nametbl(net, item, node, mtype)) 407 tipc_named_add_backlog(item, mtype, node); 408 item++; 409 } 410 kfree_skb(skb); 411 tipc_named_process_backlog(net); 412 } 413 spin_unlock_bh(&tn->nametbl_lock); 414 } 415 416 /** 417 * tipc_named_reinit - re-initialize local publications 418 * 419 * This routine is called whenever TIPC networking is enabled. 420 * All name table entries published by this node are updated to reflect 421 * the node's new network address. 422 */ 423 void tipc_named_reinit(struct net *net) 424 { 425 struct tipc_net *tn = net_generic(net, tipc_net_id); 426 struct publication *publ; 427 int scope; 428 429 spin_lock_bh(&tn->nametbl_lock); 430 431 for (scope = TIPC_ZONE_SCOPE; scope <= TIPC_NODE_SCOPE; scope++) 432 list_for_each_entry_rcu(publ, &tn->nametbl->publ_list[scope], 433 local_list) 434 publ->node = tn->own_addr; 435 436 spin_unlock_bh(&tn->nametbl_lock); 437 } 438