net/tipc/name_distr.c

   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 struct distr_queue_item {
  44         struct distr_item i;
  45         u32 dtype;
  46         u32 node;
  47         unsigned long expires;
  48         struct list_head next;
  49 };
  50
  51 /**
  52  * publ_to_item - add publication info to a publication message
  53  * @p: publication info
  54  * @i: location of item in the message
  55  */
  56 static void publ_to_item(struct distr_item *i, struct publication *p)
  57 {
  58         i->type = htonl(p->type);
  59         i->lower = htonl(p->lower);
  60         i->upper = htonl(p->upper);
  61         i->port = htonl(p->port);
  62         i->key = htonl(p->key);
  63 }
  64
  65 /**
  66  * named_prepare_buf - allocate & initialize a publication message
  67  * @net: the associated network namespace
  68  * @type: message type
  69  * @size: payload size
  70  * @dest: destination node
  71  *
  72  * The buffer returned is of size INT_H_SIZE + payload size
  73  */
  74 static struct sk_buff *named_prepare_buf(struct net *net, u32 type, u32 size,
  75                                          u32 dest)
  76 {
  77         struct sk_buff *buf = tipc_buf_acquire(INT_H_SIZE + size, GFP_ATOMIC);
  78         u32 self = tipc_own_addr(net);
  79         struct tipc_msg *msg;
  80
  81         if (buf != NULL) {
  82                 msg = buf_msg(buf);
  83                 tipc_msg_init(self, msg, NAME_DISTRIBUTOR,
  84                               type, INT_H_SIZE, dest);
  85                 msg_set_size(msg, INT_H_SIZE + size);
  86         }
  87         return buf;
  88 }
  89
  90 /**
  91  * tipc_named_publish - tell other nodes about a new publication by this node
  92  * @net: the associated network namespace
  93  * @publ: the new publication
  94  */
  95 struct sk_buff *tipc_named_publish(struct net *net, struct publication *publ)
  96 {
  97         struct name_table *nt = tipc_name_table(net);
  98         struct distr_item *item;
  99         struct sk_buff *skb;
 100
 101         if (publ->scope == TIPC_NODE_SCOPE) {
 102                 list_add_tail_rcu(&publ->binding_node, &nt->node_scope);
 103                 return NULL;
 104         }
 105         write_lock_bh(&nt->cluster_scope_lock);
 106         list_add_tail(&publ->binding_node, &nt->cluster_scope);
 107         write_unlock_bh(&nt->cluster_scope_lock);
 108         skb = named_prepare_buf(net, PUBLICATION, ITEM_SIZE, 0);
 109         if (!skb) {
 110                 pr_warn("Publication distribution failure\n");
 111                 return NULL;
 112         }
 113         msg_set_named_seqno(buf_msg(skb), nt->snd_nxt++);
 114         msg_set_non_legacy(buf_msg(skb));
 115         item = (struct distr_item *)msg_data(buf_msg(skb));
 116         publ_to_item(item, publ);
 117         return skb;
 118 }
 119
 120 /**
 121  * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
 122  * @net: the associated network namespace
 123  * @publ: the withdrawn publication
 124  */
 125 struct sk_buff *tipc_named_withdraw(struct net *net, struct publication *publ)
 126 {
 127         struct name_table *nt = tipc_name_table(net);
 128         struct distr_item *item;
 129         struct sk_buff *skb;
 130
 131         write_lock_bh(&nt->cluster_scope_lock);
 132         list_del(&publ->binding_node);
 133         write_unlock_bh(&nt->cluster_scope_lock);
 134         if (publ->scope == TIPC_NODE_SCOPE)
 135                 return NULL;
 136
 137         skb = named_prepare_buf(net, WITHDRAWAL, ITEM_SIZE, 0);
 138         if (!skb) {
 139                 pr_warn("Withdrawal distribution failure\n");
 140                 return NULL;
 141         }
 142         msg_set_named_seqno(buf_msg(skb), nt->snd_nxt++);
 143         msg_set_non_legacy(buf_msg(skb));
 144         item = (struct distr_item *)msg_data(buf_msg(skb));
 145         publ_to_item(item, publ);
 146         return skb;
 147 }
 148
 149 /**
 150  * named_distribute - prepare name info for bulk distribution to another node
 151  * @net: the associated network namespace
 152  * @list: list of messages (buffers) to be returned from this function
 153  * @dnode: node to be updated
 154  * @pls: linked list of publication items to be packed into buffer chain
 155  * @seqno: sequence number for this message
 156  */
 157 static void named_distribute(struct net *net, struct sk_buff_head *list,
 158                              u32 dnode, struct list_head *pls, u16 seqno)
 159 {
 160         struct publication *publ;
 161         struct sk_buff *skb = NULL;
 162         struct distr_item *item = NULL;
 163         u32 msg_dsz = ((tipc_node_get_mtu(net, dnode, 0, false) - INT_H_SIZE) /
 164                         ITEM_SIZE) * ITEM_SIZE;
 165         u32 msg_rem = msg_dsz;
 166         struct tipc_msg *hdr;
 167
 168         list_for_each_entry(publ, pls, binding_node) {
 169                 /* Prepare next buffer: */
 170                 if (!skb) {
 171                         skb = named_prepare_buf(net, PUBLICATION, msg_rem,
 172                                                 dnode);
 173                         if (!skb) {
 174                                 pr_warn("Bulk publication failure\n");
 175                                 return;
 176                         }
 177                         hdr = buf_msg(skb);
 178                         msg_set_bc_ack_invalid(hdr, true);
 179                         msg_set_bulk(hdr);
 180                         msg_set_non_legacy(hdr);
 181                         item = (struct distr_item *)msg_data(hdr);
 182                 }
 183
 184                 /* Pack publication into message: */
 185                 publ_to_item(item, publ);
 186                 item++;
 187                 msg_rem -= ITEM_SIZE;
 188
 189                 /* Append full buffer to list: */
 190                 if (!msg_rem) {
 191                         __skb_queue_tail(list, skb);
 192                         skb = NULL;
 193                         msg_rem = msg_dsz;
 194                 }
 195         }
 196         if (skb) {
 197                 hdr = buf_msg(skb);
 198                 msg_set_size(hdr, INT_H_SIZE + (msg_dsz - msg_rem));
 199                 skb_trim(skb, INT_H_SIZE + (msg_dsz - msg_rem));
 200                 __skb_queue_tail(list, skb);
 201         }
 202         hdr = buf_msg(skb_peek_tail(list));
 203         msg_set_last_bulk(hdr);
 204         msg_set_named_seqno(hdr, seqno);
 205 }
 206
 207 /**
 208  * tipc_named_node_up - tell specified node about all publications by this node
 209  * @net: the associated network namespace
 210  * @dnode: destination node
 211  * @capabilities: peer node's capabilities
 212  */
 213 void tipc_named_node_up(struct net *net, u32 dnode, u16 capabilities)
 214 {
 215         struct name_table *nt = tipc_name_table(net);
 216         struct tipc_net *tn = tipc_net(net);
 217         struct sk_buff_head head;
 218         u16 seqno;
 219
 220         __skb_queue_head_init(&head);
 221         spin_lock_bh(&tn->nametbl_lock);
 222         if (!(capabilities & TIPC_NAMED_BCAST))
 223                 nt->rc_dests++;
 224         seqno = nt->snd_nxt;
 225         spin_unlock_bh(&tn->nametbl_lock);
 226
 227         read_lock_bh(&nt->cluster_scope_lock);
 228         named_distribute(net, &head, dnode, &nt->cluster_scope, seqno);
 229         tipc_node_xmit(net, &head, dnode, 0);
 230         read_unlock_bh(&nt->cluster_scope_lock);
 231 }
 232
 233 /**
 234  * tipc_publ_purge - remove publication associated with a failed node
 235  * @net: the associated network namespace
 236  * @publ: the publication to remove
 237  * @addr: failed node's address
 238  *
 239  * Invoked for each publication issued by a newly failed node.
 240  * Removes publication structure from name table & deletes it.
 241  */
 242 static void tipc_publ_purge(struct net *net, struct publication *publ, u32 addr)
 243 {
 244         struct tipc_net *tn = tipc_net(net);
 245         struct publication *p;
 246
 247         spin_lock_bh(&tn->nametbl_lock);
 248         p = tipc_nametbl_remove_publ(net, publ->type, publ->lower, publ->upper,
 249                                      publ->node, publ->key);
 250         if (p)
 251                 tipc_node_unsubscribe(net, &p->binding_node, addr);
 252         spin_unlock_bh(&tn->nametbl_lock);
 253
 254         if (p != publ) {
 255                 pr_err("Unable to remove publication from failed node\n"
 256                        " (type=%u, lower=%u, node=0x%x, port=%u, key=%u)\n",
 257                        publ->type, publ->lower, publ->node, publ->port,
 258                        publ->key);
 259         }
 260
 261         if (p)
 262                 kfree_rcu(p, rcu);
 263 }
 264
 265 void tipc_publ_notify(struct net *net, struct list_head *nsub_list,
 266                       u32 addr, u16 capabilities)
 267 {
 268         struct name_table *nt = tipc_name_table(net);
 269         struct tipc_net *tn = tipc_net(net);
 270
 271         struct publication *publ, *tmp;
 272
 273         list_for_each_entry_safe(publ, tmp, nsub_list, binding_node)
 274                 tipc_publ_purge(net, publ, addr);
 275         spin_lock_bh(&tn->nametbl_lock);
 276         if (!(capabilities & TIPC_NAMED_BCAST))
 277                 nt->rc_dests--;
 278         spin_unlock_bh(&tn->nametbl_lock);
 279 }
 280
 281 /**
 282  * tipc_update_nametbl - try to process a nametable update and notify
 283  *                       subscribers
 284  * @net: the associated network namespace
 285  * @i: location of item in the message
 286  * @node: node address
 287  * @dtype: name distributor message type
 288  *
 289  * tipc_nametbl_lock must be held.
 290  * Return: the publication item if successful, otherwise NULL.
 291  */
 292 static bool tipc_update_nametbl(struct net *net, struct distr_item *i,
 293                                 u32 node, u32 dtype)
 294 {
 295         struct publication *p = NULL;
 296         u32 lower = ntohl(i->lower);
 297         u32 upper = ntohl(i->upper);
 298         u32 type = ntohl(i->type);
 299         u32 port = ntohl(i->port);
 300         u32 key = ntohl(i->key);
 301
 302         if (dtype == PUBLICATION) {
 303                 p = tipc_nametbl_insert_publ(net, type, lower, upper,
 304                                              TIPC_CLUSTER_SCOPE, node,
 305                                              port, key);
 306                 if (p) {
 307                         tipc_node_subscribe(net, &p->binding_node, node);
 308                         return true;
 309                 }
 310         } else if (dtype == WITHDRAWAL) {
 311                 p = tipc_nametbl_remove_publ(net, type, lower,
 312                                              upper, node, key);
 313                 if (p) {
 314                         tipc_node_unsubscribe(net, &p->binding_node, node);
 315                         kfree_rcu(p, rcu);
 316                         return true;
 317                 }
 318                 pr_warn_ratelimited("Failed to remove binding %u,%u from %x\n",
 319                                     type, lower, node);
 320         } else {
 321                 pr_warn("Unrecognized name table message received\n");
 322         }
 323         return false;
 324 }
 325
 326 static struct sk_buff *tipc_named_dequeue(struct sk_buff_head *namedq,
 327                                           u16 *rcv_nxt, bool *open)
 328 {
 329         struct sk_buff *skb, *tmp;
 330         struct tipc_msg *hdr;
 331         u16 seqno;
 332
 333         spin_lock_bh(&namedq->lock);
 334         skb_queue_walk_safe(namedq, skb, tmp) {
 335                 if (unlikely(skb_linearize(skb))) {
 336                         __skb_unlink(skb, namedq);
 337                         kfree_skb(skb);
 338                         continue;
 339                 }
 340                 hdr = buf_msg(skb);
 341                 seqno = msg_named_seqno(hdr);
 342                 if (msg_is_last_bulk(hdr)) {
 343                         *rcv_nxt = seqno;
 344                         *open = true;
 345                 }
 346
 347                 if (msg_is_bulk(hdr) || msg_is_legacy(hdr)) {
 348                         __skb_unlink(skb, namedq);
 349                         spin_unlock_bh(&namedq->lock);
 350                         return skb;
 351                 }
 352
 353                 if (*open && (*rcv_nxt == seqno)) {
 354                         (*rcv_nxt)++;
 355                         __skb_unlink(skb, namedq);
 356                         spin_unlock_bh(&namedq->lock);
 357                         return skb;
 358                 }
 359
 360                 if (less(seqno, *rcv_nxt)) {
 361                         __skb_unlink(skb, namedq);
 362                         kfree_skb(skb);
 363                         continue;
 364                 }
 365         }
 366         spin_unlock_bh(&namedq->lock);
 367         return NULL;
 368 }
 369
 370 /**
 371  * tipc_named_rcv - process name table update messages sent by another node
 372  * @net: the associated network namespace
 373  * @namedq: queue to receive from
 374  * @rcv_nxt: store last received seqno here
 375  * @open: last bulk msg was received (FIXME)
 376  */
 377 void tipc_named_rcv(struct net *net, struct sk_buff_head *namedq,
 378                     u16 *rcv_nxt, bool *open)
 379 {
 380         struct tipc_net *tn = tipc_net(net);
 381         struct distr_item *item;
 382         struct tipc_msg *hdr;
 383         struct sk_buff *skb;
 384         u32 count, node;
 385
 386         spin_lock_bh(&tn->nametbl_lock);
 387         while ((skb = tipc_named_dequeue(namedq, rcv_nxt, open))) {
 388                 hdr = buf_msg(skb);
 389                 node = msg_orignode(hdr);
 390                 item = (struct distr_item *)msg_data(hdr);
 391                 count = msg_data_sz(hdr) / ITEM_SIZE;
 392                 while (count--) {
 393                         tipc_update_nametbl(net, item, node, msg_type(hdr));
 394                         item++;
 395                 }
 396                 kfree_skb(skb);
 397         }
 398         spin_unlock_bh(&tn->nametbl_lock);
 399 }
 400
 401 /**
 402  * tipc_named_reinit - re-initialize local publications
 403  * @net: the associated network namespace
 404  *
 405  * This routine is called whenever TIPC networking is enabled.
 406  * All name table entries published by this node are updated to reflect
 407  * the node's new network address.
 408  */
 409 void tipc_named_reinit(struct net *net)
 410 {
 411         struct name_table *nt = tipc_name_table(net);
 412         struct tipc_net *tn = tipc_net(net);
 413         struct publication *publ;
 414         u32 self = tipc_own_addr(net);
 415
 416         spin_lock_bh(&tn->nametbl_lock);
 417
 418         list_for_each_entry_rcu(publ, &nt->node_scope, binding_node)
 419                 publ->node = self;
 420         list_for_each_entry_rcu(publ, &nt->cluster_scope, binding_node)
 421                 publ->node = self;
 422         nt->rc_dests = 0;
 423         spin_unlock_bh(&tn->nametbl_lock);
 424 }