1 #include <linux/err.h> 2 #include <linux/igmp.h> 3 #include <linux/kernel.h> 4 #include <linux/netdevice.h> 5 #include <linux/rculist.h> 6 #include <linux/skbuff.h> 7 #include <linux/if_ether.h> 8 #include <net/ip.h> 9 #include <net/netlink.h> 10 #if IS_ENABLED(CONFIG_IPV6) 11 #include <net/ipv6.h> 12 #include <net/addrconf.h> 13 #endif 14 15 #include "br_private.h" 16 17 static int br_rports_fill_info(struct sk_buff *skb, struct netlink_callback *cb, 18 struct net_device *dev) 19 { 20 struct net_bridge *br = netdev_priv(dev); 21 struct net_bridge_port *p; 22 struct nlattr *nest; 23 24 if (!br->multicast_router || hlist_empty(&br->router_list)) 25 return 0; 26 27 nest = nla_nest_start(skb, MDBA_ROUTER); 28 if (nest == NULL) 29 return -EMSGSIZE; 30 31 hlist_for_each_entry_rcu(p, &br->router_list, rlist) { 32 if (p && nla_put_u32(skb, MDBA_ROUTER_PORT, p->dev->ifindex)) 33 goto fail; 34 } 35 36 nla_nest_end(skb, nest); 37 return 0; 38 fail: 39 nla_nest_cancel(skb, nest); 40 return -EMSGSIZE; 41 } 42 43 static int br_mdb_fill_info(struct sk_buff *skb, struct netlink_callback *cb, 44 struct net_device *dev) 45 { 46 struct net_bridge *br = netdev_priv(dev); 47 struct net_bridge_mdb_htable *mdb; 48 struct nlattr *nest, *nest2; 49 int i, err = 0; 50 int idx = 0, s_idx = cb->args[1]; 51 52 if (br->multicast_disabled) 53 return 0; 54 55 mdb = rcu_dereference(br->mdb); 56 if (!mdb) 57 return 0; 58 59 nest = nla_nest_start(skb, MDBA_MDB); 60 if (nest == NULL) 61 return -EMSGSIZE; 62 63 for (i = 0; i < mdb->max; i++) { 64 struct net_bridge_mdb_entry *mp; 65 struct net_bridge_port_group *p; 66 struct net_bridge_port_group __rcu **pp; 67 struct net_bridge_port *port; 68 69 hlist_for_each_entry_rcu(mp, &mdb->mhash[i], hlist[mdb->ver]) { 70 if (idx < s_idx) 71 goto skip; 72 73 nest2 = nla_nest_start(skb, MDBA_MDB_ENTRY); 74 if (nest2 == NULL) { 75 err = -EMSGSIZE; 76 goto out; 77 } 78 79 for (pp = &mp->ports; 80 (p = rcu_dereference(*pp)) != NULL; 81 pp = &p->next) { 82 port = p->port; 83 if (port) { 84 struct br_mdb_entry e; 85 memset(&e, 0, sizeof(e)); 86 e.ifindex = port->dev->ifindex; 87 e.state = p->state; 88 if (p->addr.proto == htons(ETH_P_IP)) 89 e.addr.u.ip4 = p->addr.u.ip4; 90 #if IS_ENABLED(CONFIG_IPV6) 91 if (p->addr.proto == htons(ETH_P_IPV6)) 92 e.addr.u.ip6 = p->addr.u.ip6; 93 #endif 94 e.addr.proto = p->addr.proto; 95 if (nla_put(skb, MDBA_MDB_ENTRY_INFO, sizeof(e), &e)) { 96 nla_nest_cancel(skb, nest2); 97 err = -EMSGSIZE; 98 goto out; 99 } 100 } 101 } 102 nla_nest_end(skb, nest2); 103 skip: 104 idx++; 105 } 106 } 107 108 out: 109 cb->args[1] = idx; 110 nla_nest_end(skb, nest); 111 return err; 112 } 113 114 static int br_mdb_dump(struct sk_buff *skb, struct netlink_callback *cb) 115 { 116 struct net_device *dev; 117 struct net *net = sock_net(skb->sk); 118 struct nlmsghdr *nlh = NULL; 119 int idx = 0, s_idx; 120 121 s_idx = cb->args[0]; 122 123 rcu_read_lock(); 124 125 /* In theory this could be wrapped to 0... */ 126 cb->seq = net->dev_base_seq + br_mdb_rehash_seq; 127 128 for_each_netdev_rcu(net, dev) { 129 if (dev->priv_flags & IFF_EBRIDGE) { 130 struct br_port_msg *bpm; 131 132 if (idx < s_idx) 133 goto skip; 134 135 nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, 136 cb->nlh->nlmsg_seq, RTM_GETMDB, 137 sizeof(*bpm), NLM_F_MULTI); 138 if (nlh == NULL) 139 break; 140 141 bpm = nlmsg_data(nlh); 142 memset(bpm, 0, sizeof(*bpm)); 143 bpm->ifindex = dev->ifindex; 144 if (br_mdb_fill_info(skb, cb, dev) < 0) 145 goto out; 146 if (br_rports_fill_info(skb, cb, dev) < 0) 147 goto out; 148 149 cb->args[1] = 0; 150 nlmsg_end(skb, nlh); 151 skip: 152 idx++; 153 } 154 } 155 156 out: 157 if (nlh) 158 nlmsg_end(skb, nlh); 159 rcu_read_unlock(); 160 cb->args[0] = idx; 161 return skb->len; 162 } 163 164 static int nlmsg_populate_mdb_fill(struct sk_buff *skb, 165 struct net_device *dev, 166 struct br_mdb_entry *entry, u32 pid, 167 u32 seq, int type, unsigned int flags) 168 { 169 struct nlmsghdr *nlh; 170 struct br_port_msg *bpm; 171 struct nlattr *nest, *nest2; 172 173 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*bpm), NLM_F_MULTI); 174 if (!nlh) 175 return -EMSGSIZE; 176 177 bpm = nlmsg_data(nlh); 178 memset(bpm, 0, sizeof(*bpm)); 179 bpm->family = AF_BRIDGE; 180 bpm->ifindex = dev->ifindex; 181 nest = nla_nest_start(skb, MDBA_MDB); 182 if (nest == NULL) 183 goto cancel; 184 nest2 = nla_nest_start(skb, MDBA_MDB_ENTRY); 185 if (nest2 == NULL) 186 goto end; 187 188 if (nla_put(skb, MDBA_MDB_ENTRY_INFO, sizeof(*entry), entry)) 189 goto end; 190 191 nla_nest_end(skb, nest2); 192 nla_nest_end(skb, nest); 193 nlmsg_end(skb, nlh); 194 return 0; 195 196 end: 197 nla_nest_end(skb, nest); 198 cancel: 199 nlmsg_cancel(skb, nlh); 200 return -EMSGSIZE; 201 } 202 203 static inline size_t rtnl_mdb_nlmsg_size(void) 204 { 205 return NLMSG_ALIGN(sizeof(struct br_port_msg)) 206 + nla_total_size(sizeof(struct br_mdb_entry)); 207 } 208 209 static void __br_mdb_notify(struct net_device *dev, struct br_mdb_entry *entry, 210 int type) 211 { 212 struct net *net = dev_net(dev); 213 struct sk_buff *skb; 214 int err = -ENOBUFS; 215 216 skb = nlmsg_new(rtnl_mdb_nlmsg_size(), GFP_ATOMIC); 217 if (!skb) 218 goto errout; 219 220 err = nlmsg_populate_mdb_fill(skb, dev, entry, 0, 0, type, NTF_SELF); 221 if (err < 0) { 222 kfree_skb(skb); 223 goto errout; 224 } 225 226 rtnl_notify(skb, net, 0, RTNLGRP_MDB, NULL, GFP_ATOMIC); 227 return; 228 errout: 229 rtnl_set_sk_err(net, RTNLGRP_MDB, err); 230 } 231 232 void br_mdb_notify(struct net_device *dev, struct net_bridge_port *port, 233 struct br_ip *group, int type) 234 { 235 struct br_mdb_entry entry; 236 237 memset(&entry, 0, sizeof(entry)); 238 entry.ifindex = port->dev->ifindex; 239 entry.addr.proto = group->proto; 240 entry.addr.u.ip4 = group->u.ip4; 241 #if IS_ENABLED(CONFIG_IPV6) 242 entry.addr.u.ip6 = group->u.ip6; 243 #endif 244 __br_mdb_notify(dev, &entry, type); 245 } 246 247 static bool is_valid_mdb_entry(struct br_mdb_entry *entry) 248 { 249 if (entry->ifindex == 0) 250 return false; 251 252 if (entry->addr.proto == htons(ETH_P_IP)) { 253 if (!ipv4_is_multicast(entry->addr.u.ip4)) 254 return false; 255 if (ipv4_is_local_multicast(entry->addr.u.ip4)) 256 return false; 257 #if IS_ENABLED(CONFIG_IPV6) 258 } else if (entry->addr.proto == htons(ETH_P_IPV6)) { 259 if (ipv6_addr_is_ll_all_nodes(&entry->addr.u.ip6)) 260 return false; 261 #endif 262 } else 263 return false; 264 if (entry->state != MDB_PERMANENT && entry->state != MDB_TEMPORARY) 265 return false; 266 267 return true; 268 } 269 270 static int br_mdb_parse(struct sk_buff *skb, struct nlmsghdr *nlh, 271 struct net_device **pdev, struct br_mdb_entry **pentry) 272 { 273 struct net *net = sock_net(skb->sk); 274 struct br_mdb_entry *entry; 275 struct br_port_msg *bpm; 276 struct nlattr *tb[MDBA_SET_ENTRY_MAX+1]; 277 struct net_device *dev; 278 int err; 279 280 err = nlmsg_parse(nlh, sizeof(*bpm), tb, MDBA_SET_ENTRY_MAX, NULL); 281 if (err < 0) 282 return err; 283 284 bpm = nlmsg_data(nlh); 285 if (bpm->ifindex == 0) { 286 pr_info("PF_BRIDGE: br_mdb_parse() with invalid ifindex\n"); 287 return -EINVAL; 288 } 289 290 dev = __dev_get_by_index(net, bpm->ifindex); 291 if (dev == NULL) { 292 pr_info("PF_BRIDGE: br_mdb_parse() with unknown ifindex\n"); 293 return -ENODEV; 294 } 295 296 if (!(dev->priv_flags & IFF_EBRIDGE)) { 297 pr_info("PF_BRIDGE: br_mdb_parse() with non-bridge\n"); 298 return -EOPNOTSUPP; 299 } 300 301 *pdev = dev; 302 303 if (!tb[MDBA_SET_ENTRY] || 304 nla_len(tb[MDBA_SET_ENTRY]) != sizeof(struct br_mdb_entry)) { 305 pr_info("PF_BRIDGE: br_mdb_parse() with invalid attr\n"); 306 return -EINVAL; 307 } 308 309 entry = nla_data(tb[MDBA_SET_ENTRY]); 310 if (!is_valid_mdb_entry(entry)) { 311 pr_info("PF_BRIDGE: br_mdb_parse() with invalid entry\n"); 312 return -EINVAL; 313 } 314 315 *pentry = entry; 316 return 0; 317 } 318 319 static int br_mdb_add_group(struct net_bridge *br, struct net_bridge_port *port, 320 struct br_ip *group, unsigned char state) 321 { 322 struct net_bridge_mdb_entry *mp; 323 struct net_bridge_port_group *p; 324 struct net_bridge_port_group __rcu **pp; 325 struct net_bridge_mdb_htable *mdb; 326 int err; 327 328 mdb = mlock_dereference(br->mdb, br); 329 mp = br_mdb_ip_get(mdb, group); 330 if (!mp) { 331 mp = br_multicast_new_group(br, port, group); 332 err = PTR_ERR(mp); 333 if (IS_ERR(mp)) 334 return err; 335 } 336 337 for (pp = &mp->ports; 338 (p = mlock_dereference(*pp, br)) != NULL; 339 pp = &p->next) { 340 if (p->port == port) 341 return -EEXIST; 342 if ((unsigned long)p->port < (unsigned long)port) 343 break; 344 } 345 346 p = br_multicast_new_port_group(port, group, *pp, state); 347 if (unlikely(!p)) 348 return -ENOMEM; 349 rcu_assign_pointer(*pp, p); 350 351 br_mdb_notify(br->dev, port, group, RTM_NEWMDB); 352 return 0; 353 } 354 355 static int __br_mdb_add(struct net *net, struct net_bridge *br, 356 struct br_mdb_entry *entry) 357 { 358 struct br_ip ip; 359 struct net_device *dev; 360 struct net_bridge_port *p; 361 int ret; 362 363 if (!netif_running(br->dev) || br->multicast_disabled) 364 return -EINVAL; 365 366 dev = __dev_get_by_index(net, entry->ifindex); 367 if (!dev) 368 return -ENODEV; 369 370 p = br_port_get_rtnl(dev); 371 if (!p || p->br != br || p->state == BR_STATE_DISABLED) 372 return -EINVAL; 373 374 ip.proto = entry->addr.proto; 375 if (ip.proto == htons(ETH_P_IP)) 376 ip.u.ip4 = entry->addr.u.ip4; 377 #if IS_ENABLED(CONFIG_IPV6) 378 else 379 ip.u.ip6 = entry->addr.u.ip6; 380 #endif 381 382 spin_lock_bh(&br->multicast_lock); 383 ret = br_mdb_add_group(br, p, &ip, entry->state); 384 spin_unlock_bh(&br->multicast_lock); 385 return ret; 386 } 387 388 static int br_mdb_add(struct sk_buff *skb, struct nlmsghdr *nlh) 389 { 390 struct net *net = sock_net(skb->sk); 391 struct br_mdb_entry *entry; 392 struct net_device *dev; 393 struct net_bridge *br; 394 int err; 395 396 err = br_mdb_parse(skb, nlh, &dev, &entry); 397 if (err < 0) 398 return err; 399 400 br = netdev_priv(dev); 401 402 err = __br_mdb_add(net, br, entry); 403 if (!err) 404 __br_mdb_notify(dev, entry, RTM_NEWMDB); 405 return err; 406 } 407 408 static int __br_mdb_del(struct net_bridge *br, struct br_mdb_entry *entry) 409 { 410 struct net_bridge_mdb_htable *mdb; 411 struct net_bridge_mdb_entry *mp; 412 struct net_bridge_port_group *p; 413 struct net_bridge_port_group __rcu **pp; 414 struct br_ip ip; 415 int err = -EINVAL; 416 417 if (!netif_running(br->dev) || br->multicast_disabled) 418 return -EINVAL; 419 420 ip.proto = entry->addr.proto; 421 if (ip.proto == htons(ETH_P_IP)) { 422 if (timer_pending(&br->ip4_other_query.timer)) 423 return -EBUSY; 424 425 ip.u.ip4 = entry->addr.u.ip4; 426 #if IS_ENABLED(CONFIG_IPV6) 427 } else { 428 if (timer_pending(&br->ip6_other_query.timer)) 429 return -EBUSY; 430 431 ip.u.ip6 = entry->addr.u.ip6; 432 #endif 433 } 434 435 spin_lock_bh(&br->multicast_lock); 436 mdb = mlock_dereference(br->mdb, br); 437 438 mp = br_mdb_ip_get(mdb, &ip); 439 if (!mp) 440 goto unlock; 441 442 for (pp = &mp->ports; 443 (p = mlock_dereference(*pp, br)) != NULL; 444 pp = &p->next) { 445 if (!p->port || p->port->dev->ifindex != entry->ifindex) 446 continue; 447 448 if (p->port->state == BR_STATE_DISABLED) 449 goto unlock; 450 451 rcu_assign_pointer(*pp, p->next); 452 hlist_del_init(&p->mglist); 453 del_timer(&p->timer); 454 call_rcu_bh(&p->rcu, br_multicast_free_pg); 455 err = 0; 456 457 if (!mp->ports && !mp->mglist && 458 netif_running(br->dev)) 459 mod_timer(&mp->timer, jiffies); 460 break; 461 } 462 463 unlock: 464 spin_unlock_bh(&br->multicast_lock); 465 return err; 466 } 467 468 static int br_mdb_del(struct sk_buff *skb, struct nlmsghdr *nlh) 469 { 470 struct net_device *dev; 471 struct br_mdb_entry *entry; 472 struct net_bridge *br; 473 int err; 474 475 err = br_mdb_parse(skb, nlh, &dev, &entry); 476 if (err < 0) 477 return err; 478 479 br = netdev_priv(dev); 480 481 err = __br_mdb_del(br, entry); 482 if (!err) 483 __br_mdb_notify(dev, entry, RTM_DELMDB); 484 return err; 485 } 486 487 void br_mdb_init(void) 488 { 489 rtnl_register(PF_BRIDGE, RTM_GETMDB, NULL, br_mdb_dump, NULL); 490 rtnl_register(PF_BRIDGE, RTM_NEWMDB, br_mdb_add, NULL, NULL); 491 rtnl_register(PF_BRIDGE, RTM_DELMDB, br_mdb_del, NULL, NULL); 492 } 493 494 void br_mdb_uninit(void) 495 { 496 rtnl_unregister(PF_BRIDGE, RTM_GETMDB); 497 rtnl_unregister(PF_BRIDGE, RTM_NEWMDB); 498 rtnl_unregister(PF_BRIDGE, RTM_DELMDB); 499 } 500