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
br_rports_fill_info(struct sk_buff * skb,struct netlink_callback * cb,struct net_device * dev)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
br_mdb_fill_info(struct sk_buff * skb,struct netlink_callback * cb,struct net_device * dev)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 e.vid = p->addr.vid;
89 if (p->addr.proto == htons(ETH_P_IP))
90 e.addr.u.ip4 = p->addr.u.ip4;
91 #if IS_ENABLED(CONFIG_IPV6)
92 if (p->addr.proto == htons(ETH_P_IPV6))
93 e.addr.u.ip6 = p->addr.u.ip6;
94 #endif
95 e.addr.proto = p->addr.proto;
96 if (nla_put(skb, MDBA_MDB_ENTRY_INFO, sizeof(e), &e)) {
97 nla_nest_cancel(skb, nest2);
98 err = -EMSGSIZE;
99 goto out;
100 }
101 }
102 }
103 nla_nest_end(skb, nest2);
104 skip:
105 idx++;
106 }
107 }
108
109 out:
110 cb->args[1] = idx;
111 nla_nest_end(skb, nest);
112 return err;
113 }
114
br_mdb_dump(struct sk_buff * skb,struct netlink_callback * cb)115 static int br_mdb_dump(struct sk_buff *skb, struct netlink_callback *cb)
116 {
117 struct net_device *dev;
118 struct net *net = sock_net(skb->sk);
119 struct nlmsghdr *nlh = NULL;
120 int idx = 0, s_idx;
121
122 s_idx = cb->args[0];
123
124 rcu_read_lock();
125
126 /* In theory this could be wrapped to 0... */
127 cb->seq = net->dev_base_seq + br_mdb_rehash_seq;
128
129 for_each_netdev_rcu(net, dev) {
130 if (dev->priv_flags & IFF_EBRIDGE) {
131 struct br_port_msg *bpm;
132
133 if (idx < s_idx)
134 goto skip;
135
136 nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid,
137 cb->nlh->nlmsg_seq, RTM_GETMDB,
138 sizeof(*bpm), NLM_F_MULTI);
139 if (nlh == NULL)
140 break;
141
142 bpm = nlmsg_data(nlh);
143 memset(bpm, 0, sizeof(*bpm));
144 bpm->ifindex = dev->ifindex;
145 if (br_mdb_fill_info(skb, cb, dev) < 0)
146 goto out;
147 if (br_rports_fill_info(skb, cb, dev) < 0)
148 goto out;
149
150 cb->args[1] = 0;
151 nlmsg_end(skb, nlh);
152 skip:
153 idx++;
154 }
155 }
156
157 out:
158 if (nlh)
159 nlmsg_end(skb, nlh);
160 rcu_read_unlock();
161 cb->args[0] = idx;
162 return skb->len;
163 }
164
nlmsg_populate_mdb_fill(struct sk_buff * skb,struct net_device * dev,struct br_mdb_entry * entry,u32 pid,u32 seq,int type,unsigned int flags)165 static int nlmsg_populate_mdb_fill(struct sk_buff *skb,
166 struct net_device *dev,
167 struct br_mdb_entry *entry, u32 pid,
168 u32 seq, int type, unsigned int flags)
169 {
170 struct nlmsghdr *nlh;
171 struct br_port_msg *bpm;
172 struct nlattr *nest, *nest2;
173
174 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*bpm), 0);
175 if (!nlh)
176 return -EMSGSIZE;
177
178 bpm = nlmsg_data(nlh);
179 memset(bpm, 0, sizeof(*bpm));
180 bpm->family = AF_BRIDGE;
181 bpm->ifindex = dev->ifindex;
182 nest = nla_nest_start(skb, MDBA_MDB);
183 if (nest == NULL)
184 goto cancel;
185 nest2 = nla_nest_start(skb, MDBA_MDB_ENTRY);
186 if (nest2 == NULL)
187 goto end;
188
189 if (nla_put(skb, MDBA_MDB_ENTRY_INFO, sizeof(*entry), entry))
190 goto end;
191
192 nla_nest_end(skb, nest2);
193 nla_nest_end(skb, nest);
194 nlmsg_end(skb, nlh);
195 return 0;
196
197 end:
198 nla_nest_end(skb, nest);
199 cancel:
200 nlmsg_cancel(skb, nlh);
201 return -EMSGSIZE;
202 }
203
rtnl_mdb_nlmsg_size(void)204 static inline size_t rtnl_mdb_nlmsg_size(void)
205 {
206 return NLMSG_ALIGN(sizeof(struct br_port_msg))
207 + nla_total_size(sizeof(struct br_mdb_entry));
208 }
209
__br_mdb_notify(struct net_device * dev,struct br_mdb_entry * entry,int type)210 static void __br_mdb_notify(struct net_device *dev, struct br_mdb_entry *entry,
211 int type)
212 {
213 struct net *net = dev_net(dev);
214 struct sk_buff *skb;
215 int err = -ENOBUFS;
216
217 skb = nlmsg_new(rtnl_mdb_nlmsg_size(), GFP_ATOMIC);
218 if (!skb)
219 goto errout;
220
221 err = nlmsg_populate_mdb_fill(skb, dev, entry, 0, 0, type, NTF_SELF);
222 if (err < 0) {
223 kfree_skb(skb);
224 goto errout;
225 }
226
227 rtnl_notify(skb, net, 0, RTNLGRP_MDB, NULL, GFP_ATOMIC);
228 return;
229 errout:
230 rtnl_set_sk_err(net, RTNLGRP_MDB, err);
231 }
232
br_mdb_notify(struct net_device * dev,struct net_bridge_port * port,struct br_ip * group,int type,u8 state)233 void br_mdb_notify(struct net_device *dev, struct net_bridge_port *port,
234 struct br_ip *group, int type, u8 state)
235 {
236 struct br_mdb_entry entry;
237
238 memset(&entry, 0, sizeof(entry));
239 entry.ifindex = port->dev->ifindex;
240 entry.addr.proto = group->proto;
241 entry.addr.u.ip4 = group->u.ip4;
242 #if IS_ENABLED(CONFIG_IPV6)
243 entry.addr.u.ip6 = group->u.ip6;
244 #endif
245 entry.state = state;
246 entry.vid = group->vid;
247 __br_mdb_notify(dev, &entry, type);
248 }
249
nlmsg_populate_rtr_fill(struct sk_buff * skb,struct net_device * dev,int ifindex,u32 pid,u32 seq,int type,unsigned int flags)250 static int nlmsg_populate_rtr_fill(struct sk_buff *skb,
251 struct net_device *dev,
252 int ifindex, u32 pid,
253 u32 seq, int type, unsigned int flags)
254 {
255 struct br_port_msg *bpm;
256 struct nlmsghdr *nlh;
257 struct nlattr *nest;
258
259 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*bpm), 0);
260 if (!nlh)
261 return -EMSGSIZE;
262
263 bpm = nlmsg_data(nlh);
264 memset(bpm, 0, sizeof(*bpm));
265 bpm->family = AF_BRIDGE;
266 bpm->ifindex = dev->ifindex;
267 nest = nla_nest_start(skb, MDBA_ROUTER);
268 if (!nest)
269 goto cancel;
270
271 if (nla_put_u32(skb, MDBA_ROUTER_PORT, ifindex))
272 goto end;
273
274 nla_nest_end(skb, nest);
275 nlmsg_end(skb, nlh);
276 return 0;
277
278 end:
279 nla_nest_end(skb, nest);
280 cancel:
281 nlmsg_cancel(skb, nlh);
282 return -EMSGSIZE;
283 }
284
rtnl_rtr_nlmsg_size(void)285 static inline size_t rtnl_rtr_nlmsg_size(void)
286 {
287 return NLMSG_ALIGN(sizeof(struct br_port_msg))
288 + nla_total_size(sizeof(__u32));
289 }
290
br_rtr_notify(struct net_device * dev,struct net_bridge_port * port,int type)291 void br_rtr_notify(struct net_device *dev, struct net_bridge_port *port,
292 int type)
293 {
294 struct net *net = dev_net(dev);
295 struct sk_buff *skb;
296 int err = -ENOBUFS;
297 int ifindex;
298
299 ifindex = port ? port->dev->ifindex : 0;
300 skb = nlmsg_new(rtnl_rtr_nlmsg_size(), GFP_ATOMIC);
301 if (!skb)
302 goto errout;
303
304 err = nlmsg_populate_rtr_fill(skb, dev, ifindex, 0, 0, type, NTF_SELF);
305 if (err < 0) {
306 kfree_skb(skb);
307 goto errout;
308 }
309
310 rtnl_notify(skb, net, 0, RTNLGRP_MDB, NULL, GFP_ATOMIC);
311 return;
312
313 errout:
314 rtnl_set_sk_err(net, RTNLGRP_MDB, err);
315 }
316
is_valid_mdb_entry(struct br_mdb_entry * entry)317 static bool is_valid_mdb_entry(struct br_mdb_entry *entry)
318 {
319 if (entry->ifindex == 0)
320 return false;
321
322 if (entry->addr.proto == htons(ETH_P_IP)) {
323 if (!ipv4_is_multicast(entry->addr.u.ip4))
324 return false;
325 if (ipv4_is_local_multicast(entry->addr.u.ip4))
326 return false;
327 #if IS_ENABLED(CONFIG_IPV6)
328 } else if (entry->addr.proto == htons(ETH_P_IPV6)) {
329 if (ipv6_addr_is_ll_all_nodes(&entry->addr.u.ip6))
330 return false;
331 #endif
332 } else
333 return false;
334 if (entry->state != MDB_PERMANENT && entry->state != MDB_TEMPORARY)
335 return false;
336 if (entry->vid >= VLAN_VID_MASK)
337 return false;
338
339 return true;
340 }
341
br_mdb_parse(struct sk_buff * skb,struct nlmsghdr * nlh,struct net_device ** pdev,struct br_mdb_entry ** pentry)342 static int br_mdb_parse(struct sk_buff *skb, struct nlmsghdr *nlh,
343 struct net_device **pdev, struct br_mdb_entry **pentry)
344 {
345 struct net *net = sock_net(skb->sk);
346 struct br_mdb_entry *entry;
347 struct br_port_msg *bpm;
348 struct nlattr *tb[MDBA_SET_ENTRY_MAX+1];
349 struct net_device *dev;
350 int err;
351
352 err = nlmsg_parse(nlh, sizeof(*bpm), tb, MDBA_SET_ENTRY_MAX, NULL);
353 if (err < 0)
354 return err;
355
356 bpm = nlmsg_data(nlh);
357 if (bpm->ifindex == 0) {
358 pr_info("PF_BRIDGE: br_mdb_parse() with invalid ifindex\n");
359 return -EINVAL;
360 }
361
362 dev = __dev_get_by_index(net, bpm->ifindex);
363 if (dev == NULL) {
364 pr_info("PF_BRIDGE: br_mdb_parse() with unknown ifindex\n");
365 return -ENODEV;
366 }
367
368 if (!(dev->priv_flags & IFF_EBRIDGE)) {
369 pr_info("PF_BRIDGE: br_mdb_parse() with non-bridge\n");
370 return -EOPNOTSUPP;
371 }
372
373 *pdev = dev;
374
375 if (!tb[MDBA_SET_ENTRY] ||
376 nla_len(tb[MDBA_SET_ENTRY]) != sizeof(struct br_mdb_entry)) {
377 pr_info("PF_BRIDGE: br_mdb_parse() with invalid attr\n");
378 return -EINVAL;
379 }
380
381 entry = nla_data(tb[MDBA_SET_ENTRY]);
382 if (!is_valid_mdb_entry(entry)) {
383 pr_info("PF_BRIDGE: br_mdb_parse() with invalid entry\n");
384 return -EINVAL;
385 }
386
387 *pentry = entry;
388 return 0;
389 }
390
br_mdb_add_group(struct net_bridge * br,struct net_bridge_port * port,struct br_ip * group,unsigned char state)391 static int br_mdb_add_group(struct net_bridge *br, struct net_bridge_port *port,
392 struct br_ip *group, unsigned char state)
393 {
394 struct net_bridge_mdb_entry *mp;
395 struct net_bridge_port_group *p;
396 struct net_bridge_port_group __rcu **pp;
397 struct net_bridge_mdb_htable *mdb;
398 unsigned long now = jiffies;
399 int err;
400
401 mdb = mlock_dereference(br->mdb, br);
402 mp = br_mdb_ip_get(mdb, group);
403 if (!mp) {
404 mp = br_multicast_new_group(br, port, group);
405 err = PTR_ERR(mp);
406 if (IS_ERR(mp))
407 return err;
408 }
409
410 for (pp = &mp->ports;
411 (p = mlock_dereference(*pp, br)) != NULL;
412 pp = &p->next) {
413 if (p->port == port)
414 return -EEXIST;
415 if ((unsigned long)p->port < (unsigned long)port)
416 break;
417 }
418
419 p = br_multicast_new_port_group(port, group, *pp, state);
420 if (unlikely(!p))
421 return -ENOMEM;
422 rcu_assign_pointer(*pp, p);
423 if (state == MDB_TEMPORARY)
424 mod_timer(&p->timer, now + br->multicast_membership_interval);
425
426 return 0;
427 }
428
__br_mdb_add(struct net * net,struct net_bridge * br,struct br_mdb_entry * entry)429 static int __br_mdb_add(struct net *net, struct net_bridge *br,
430 struct br_mdb_entry *entry)
431 {
432 struct br_ip ip;
433 struct net_device *dev;
434 struct net_bridge_port *p;
435 int ret;
436
437 if (!netif_running(br->dev) || br->multicast_disabled)
438 return -EINVAL;
439
440 dev = __dev_get_by_index(net, entry->ifindex);
441 if (!dev)
442 return -ENODEV;
443
444 p = br_port_get_rtnl(dev);
445 if (!p || p->br != br || p->state == BR_STATE_DISABLED)
446 return -EINVAL;
447
448 memset(&ip, 0, sizeof(ip));
449 ip.vid = entry->vid;
450 ip.proto = entry->addr.proto;
451 if (ip.proto == htons(ETH_P_IP))
452 ip.u.ip4 = entry->addr.u.ip4;
453 #if IS_ENABLED(CONFIG_IPV6)
454 else
455 ip.u.ip6 = entry->addr.u.ip6;
456 #endif
457
458 spin_lock_bh(&br->multicast_lock);
459 ret = br_mdb_add_group(br, p, &ip, entry->state);
460 spin_unlock_bh(&br->multicast_lock);
461 return ret;
462 }
463
br_mdb_add(struct sk_buff * skb,struct nlmsghdr * nlh)464 static int br_mdb_add(struct sk_buff *skb, struct nlmsghdr *nlh)
465 {
466 struct net *net = sock_net(skb->sk);
467 struct net_bridge_vlan_group *vg;
468 struct net_device *dev, *pdev;
469 struct br_mdb_entry *entry;
470 struct net_bridge_port *p;
471 struct net_bridge_vlan *v;
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 /* If vlan filtering is enabled and VLAN is not specified
482 * install mdb entry on all vlans configured on the port.
483 */
484 pdev = __dev_get_by_index(net, entry->ifindex);
485 if (!pdev)
486 return -ENODEV;
487
488 p = br_port_get_rtnl(pdev);
489 if (!p || p->br != br || p->state == BR_STATE_DISABLED)
490 return -EINVAL;
491
492 vg = nbp_vlan_group(p);
493 if (br_vlan_enabled(br) && vg && entry->vid == 0) {
494 list_for_each_entry(v, &vg->vlan_list, vlist) {
495 entry->vid = v->vid;
496 err = __br_mdb_add(net, br, entry);
497 if (err)
498 break;
499 __br_mdb_notify(dev, entry, RTM_NEWMDB);
500 }
501 } else {
502 err = __br_mdb_add(net, br, entry);
503 if (!err)
504 __br_mdb_notify(dev, entry, RTM_NEWMDB);
505 }
506
507 return err;
508 }
509
__br_mdb_del(struct net_bridge * br,struct br_mdb_entry * entry)510 static int __br_mdb_del(struct net_bridge *br, struct br_mdb_entry *entry)
511 {
512 struct net_bridge_mdb_htable *mdb;
513 struct net_bridge_mdb_entry *mp;
514 struct net_bridge_port_group *p;
515 struct net_bridge_port_group __rcu **pp;
516 struct br_ip ip;
517 int err = -EINVAL;
518
519 if (!netif_running(br->dev) || br->multicast_disabled)
520 return -EINVAL;
521
522 memset(&ip, 0, sizeof(ip));
523 ip.vid = entry->vid;
524 ip.proto = entry->addr.proto;
525 if (ip.proto == htons(ETH_P_IP))
526 ip.u.ip4 = entry->addr.u.ip4;
527 #if IS_ENABLED(CONFIG_IPV6)
528 else
529 ip.u.ip6 = entry->addr.u.ip6;
530 #endif
531
532 spin_lock_bh(&br->multicast_lock);
533 mdb = mlock_dereference(br->mdb, br);
534
535 mp = br_mdb_ip_get(mdb, &ip);
536 if (!mp)
537 goto unlock;
538
539 for (pp = &mp->ports;
540 (p = mlock_dereference(*pp, br)) != NULL;
541 pp = &p->next) {
542 if (!p->port || p->port->dev->ifindex != entry->ifindex)
543 continue;
544
545 if (p->port->state == BR_STATE_DISABLED)
546 goto unlock;
547
548 entry->state = p->state;
549 rcu_assign_pointer(*pp, p->next);
550 hlist_del_init(&p->mglist);
551 del_timer(&p->timer);
552 call_rcu_bh(&p->rcu, br_multicast_free_pg);
553 err = 0;
554
555 if (!mp->ports && !mp->mglist &&
556 netif_running(br->dev))
557 mod_timer(&mp->timer, jiffies);
558 break;
559 }
560
561 unlock:
562 spin_unlock_bh(&br->multicast_lock);
563 return err;
564 }
565
br_mdb_del(struct sk_buff * skb,struct nlmsghdr * nlh)566 static int br_mdb_del(struct sk_buff *skb, struct nlmsghdr *nlh)
567 {
568 struct net *net = sock_net(skb->sk);
569 struct net_bridge_vlan_group *vg;
570 struct net_device *dev, *pdev;
571 struct br_mdb_entry *entry;
572 struct net_bridge_port *p;
573 struct net_bridge_vlan *v;
574 struct net_bridge *br;
575 int err;
576
577 err = br_mdb_parse(skb, nlh, &dev, &entry);
578 if (err < 0)
579 return err;
580
581 br = netdev_priv(dev);
582
583 /* If vlan filtering is enabled and VLAN is not specified
584 * delete mdb entry on all vlans configured on the port.
585 */
586 pdev = __dev_get_by_index(net, entry->ifindex);
587 if (!pdev)
588 return -ENODEV;
589
590 p = br_port_get_rtnl(pdev);
591 if (!p || p->br != br || p->state == BR_STATE_DISABLED)
592 return -EINVAL;
593
594 vg = nbp_vlan_group(p);
595 if (br_vlan_enabled(br) && vg && entry->vid == 0) {
596 list_for_each_entry(v, &vg->vlan_list, vlist) {
597 entry->vid = v->vid;
598 err = __br_mdb_del(br, entry);
599 if (!err)
600 __br_mdb_notify(dev, entry, RTM_DELMDB);
601 }
602 } else {
603 err = __br_mdb_del(br, entry);
604 if (!err)
605 __br_mdb_notify(dev, entry, RTM_DELMDB);
606 }
607
608 return err;
609 }
610
br_mdb_init(void)611 void br_mdb_init(void)
612 {
613 rtnl_register(PF_BRIDGE, RTM_GETMDB, NULL, br_mdb_dump, NULL);
614 rtnl_register(PF_BRIDGE, RTM_NEWMDB, br_mdb_add, NULL, NULL);
615 rtnl_register(PF_BRIDGE, RTM_DELMDB, br_mdb_del, NULL, NULL);
616 }
617
br_mdb_uninit(void)618 void br_mdb_uninit(void)
619 {
620 rtnl_unregister(PF_BRIDGE, RTM_GETMDB);
621 rtnl_unregister(PF_BRIDGE, RTM_NEWMDB);
622 rtnl_unregister(PF_BRIDGE, RTM_DELMDB);
623 }
624