Commit | Line | Data |
---|---|---|
482a8524 TG |
1 | /* |
2 | * NETLINK Generic Netlink Family | |
3 | * | |
4 | * Authors: Jamal Hadi Salim | |
5 | * Thomas Graf <tgraf@suug.ch> | |
2dbba6f7 | 6 | * Johannes Berg <johannes@sipsolutions.net> |
482a8524 TG |
7 | */ |
8 | ||
482a8524 TG |
9 | #include <linux/module.h> |
10 | #include <linux/kernel.h> | |
11 | #include <linux/errno.h> | |
12 | #include <linux/types.h> | |
13 | #include <linux/socket.h> | |
14 | #include <linux/string.h> | |
15 | #include <linux/skbuff.h> | |
14cc3e2b | 16 | #include <linux/mutex.h> |
2dbba6f7 | 17 | #include <linux/bitmap.h> |
482a8524 TG |
18 | #include <net/sock.h> |
19 | #include <net/genetlink.h> | |
20 | ||
14cc3e2b | 21 | static DEFINE_MUTEX(genl_mutex); /* serialization of message processing */ |
482a8524 | 22 | |
3b71535f | 23 | static inline void genl_lock(void) |
482a8524 | 24 | { |
14cc3e2b | 25 | mutex_lock(&genl_mutex); |
482a8524 TG |
26 | } |
27 | ||
3b71535f | 28 | static inline void genl_unlock(void) |
482a8524 | 29 | { |
14cc3e2b | 30 | mutex_unlock(&genl_mutex); |
482a8524 TG |
31 | } |
32 | ||
33 | #define GENL_FAM_TAB_SIZE 16 | |
34 | #define GENL_FAM_TAB_MASK (GENL_FAM_TAB_SIZE - 1) | |
35 | ||
36 | static struct list_head family_ht[GENL_FAM_TAB_SIZE]; | |
2dbba6f7 JB |
37 | /* |
38 | * Bitmap of multicast groups that are currently in use. | |
39 | * | |
40 | * To avoid an allocation at boot of just one unsigned long, | |
41 | * declare it global instead. | |
42 | * Bit 0 is marked as already used since group 0 is invalid. | |
43 | */ | |
44 | static unsigned long mc_group_start = 0x1; | |
45 | static unsigned long *mc_groups = &mc_group_start; | |
46 | static unsigned long mc_groups_longs = 1; | |
482a8524 TG |
47 | |
48 | static int genl_ctrl_event(int event, void *data); | |
49 | ||
50 | static inline unsigned int genl_family_hash(unsigned int id) | |
51 | { | |
52 | return id & GENL_FAM_TAB_MASK; | |
53 | } | |
54 | ||
55 | static inline struct list_head *genl_family_chain(unsigned int id) | |
56 | { | |
57 | return &family_ht[genl_family_hash(id)]; | |
58 | } | |
59 | ||
60 | static struct genl_family *genl_family_find_byid(unsigned int id) | |
61 | { | |
62 | struct genl_family *f; | |
63 | ||
64 | list_for_each_entry(f, genl_family_chain(id), family_list) | |
65 | if (f->id == id) | |
66 | return f; | |
67 | ||
68 | return NULL; | |
69 | } | |
70 | ||
71 | static struct genl_family *genl_family_find_byname(char *name) | |
72 | { | |
73 | struct genl_family *f; | |
74 | int i; | |
75 | ||
76 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) | |
77 | list_for_each_entry(f, genl_family_chain(i), family_list) | |
78 | if (strcmp(f->name, name) == 0) | |
79 | return f; | |
80 | ||
81 | return NULL; | |
82 | } | |
83 | ||
84 | static struct genl_ops *genl_get_cmd(u8 cmd, struct genl_family *family) | |
85 | { | |
86 | struct genl_ops *ops; | |
87 | ||
88 | list_for_each_entry(ops, &family->ops_list, ops_list) | |
89 | if (ops->cmd == cmd) | |
90 | return ops; | |
91 | ||
92 | return NULL; | |
93 | } | |
94 | ||
95 | /* Of course we are going to have problems once we hit | |
96 | * 2^16 alive types, but that can only happen by year 2K | |
97 | */ | |
98 | static inline u16 genl_generate_id(void) | |
99 | { | |
100 | static u16 id_gen_idx; | |
101 | int overflowed = 0; | |
102 | ||
103 | do { | |
104 | if (id_gen_idx == 0) | |
105 | id_gen_idx = GENL_MIN_ID; | |
106 | ||
107 | if (++id_gen_idx > GENL_MAX_ID) { | |
108 | if (!overflowed) { | |
109 | overflowed = 1; | |
110 | id_gen_idx = 0; | |
111 | continue; | |
112 | } else | |
113 | return 0; | |
114 | } | |
115 | ||
116 | } while (genl_family_find_byid(id_gen_idx)); | |
117 | ||
118 | return id_gen_idx; | |
119 | } | |
120 | ||
2dbba6f7 JB |
121 | static struct genl_multicast_group notify_grp; |
122 | ||
123 | /** | |
124 | * genl_register_mc_group - register a multicast group | |
125 | * | |
126 | * Registers the specified multicast group and notifies userspace | |
127 | * about the new group. | |
128 | * | |
129 | * Returns 0 on success or a negative error code. | |
130 | * | |
131 | * @family: The generic netlink family the group shall be registered for. | |
132 | * @grp: The group to register, must have a name. | |
133 | */ | |
134 | int genl_register_mc_group(struct genl_family *family, | |
135 | struct genl_multicast_group *grp) | |
136 | { | |
137 | int id; | |
138 | unsigned long *new_groups; | |
139 | int err; | |
140 | ||
141 | BUG_ON(grp->name[0] == '\0'); | |
142 | ||
143 | genl_lock(); | |
144 | ||
145 | /* special-case our own group */ | |
146 | if (grp == ¬ify_grp) | |
147 | id = GENL_ID_CTRL; | |
148 | else | |
149 | id = find_first_zero_bit(mc_groups, | |
150 | mc_groups_longs * BITS_PER_LONG); | |
151 | ||
152 | ||
153 | if (id >= mc_groups_longs * BITS_PER_LONG) { | |
154 | size_t nlen = (mc_groups_longs + 1) * sizeof(unsigned long); | |
155 | ||
156 | if (mc_groups == &mc_group_start) { | |
157 | new_groups = kzalloc(nlen, GFP_KERNEL); | |
158 | if (!new_groups) { | |
159 | err = -ENOMEM; | |
160 | goto out; | |
161 | } | |
162 | mc_groups = new_groups; | |
163 | *mc_groups = mc_group_start; | |
164 | } else { | |
165 | new_groups = krealloc(mc_groups, nlen, GFP_KERNEL); | |
166 | if (!new_groups) { | |
167 | err = -ENOMEM; | |
168 | goto out; | |
169 | } | |
170 | mc_groups = new_groups; | |
171 | mc_groups[mc_groups_longs] = 0; | |
172 | } | |
173 | mc_groups_longs++; | |
174 | } | |
175 | ||
134e6375 JB |
176 | if (family->netnsok) { |
177 | struct net *net; | |
178 | ||
179 | rcu_read_lock(); | |
180 | for_each_net_rcu(net) { | |
181 | err = netlink_change_ngroups(net->genl_sock, | |
182 | mc_groups_longs * BITS_PER_LONG); | |
183 | if (err) { | |
184 | /* | |
185 | * No need to roll back, can only fail if | |
186 | * memory allocation fails and then the | |
187 | * number of _possible_ groups has been | |
188 | * increased on some sockets which is ok. | |
189 | */ | |
190 | rcu_read_unlock(); | |
191 | goto out; | |
192 | } | |
193 | } | |
194 | rcu_read_unlock(); | |
195 | } else { | |
196 | err = netlink_change_ngroups(init_net.genl_sock, | |
197 | mc_groups_longs * BITS_PER_LONG); | |
198 | if (err) | |
199 | goto out; | |
200 | } | |
2dbba6f7 JB |
201 | |
202 | grp->id = id; | |
203 | set_bit(id, mc_groups); | |
204 | list_add_tail(&grp->list, &family->mcast_groups); | |
205 | grp->family = family; | |
206 | ||
207 | genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, grp); | |
208 | out: | |
209 | genl_unlock(); | |
79d310d0 | 210 | return err; |
2dbba6f7 JB |
211 | } |
212 | EXPORT_SYMBOL(genl_register_mc_group); | |
213 | ||
79dc4386 TG |
214 | static void __genl_unregister_mc_group(struct genl_family *family, |
215 | struct genl_multicast_group *grp) | |
216 | { | |
134e6375 | 217 | struct net *net; |
79dc4386 | 218 | BUG_ON(grp->family != family); |
134e6375 JB |
219 | |
220 | rcu_read_lock(); | |
221 | for_each_net_rcu(net) | |
222 | netlink_clear_multicast_users(net->genl_sock, grp->id); | |
223 | rcu_read_unlock(); | |
224 | ||
79dc4386 TG |
225 | clear_bit(grp->id, mc_groups); |
226 | list_del(&grp->list); | |
227 | genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, grp); | |
228 | grp->id = 0; | |
229 | grp->family = NULL; | |
230 | } | |
231 | ||
2dbba6f7 JB |
232 | /** |
233 | * genl_unregister_mc_group - unregister a multicast group | |
234 | * | |
235 | * Unregisters the specified multicast group and notifies userspace | |
236 | * about it. All current listeners on the group are removed. | |
237 | * | |
238 | * Note: It is not necessary to unregister all multicast groups before | |
239 | * unregistering the family, unregistering the family will cause | |
240 | * all assigned multicast groups to be unregistered automatically. | |
241 | * | |
242 | * @family: Generic netlink family the group belongs to. | |
243 | * @grp: The group to unregister, must have been registered successfully | |
244 | * previously. | |
245 | */ | |
246 | void genl_unregister_mc_group(struct genl_family *family, | |
247 | struct genl_multicast_group *grp) | |
248 | { | |
2dbba6f7 | 249 | genl_lock(); |
79dc4386 | 250 | __genl_unregister_mc_group(family, grp); |
2dbba6f7 JB |
251 | genl_unlock(); |
252 | } | |
3efb40c2 | 253 | EXPORT_SYMBOL(genl_unregister_mc_group); |
2dbba6f7 JB |
254 | |
255 | static void genl_unregister_mc_groups(struct genl_family *family) | |
256 | { | |
257 | struct genl_multicast_group *grp, *tmp; | |
258 | ||
259 | list_for_each_entry_safe(grp, tmp, &family->mcast_groups, list) | |
79dc4386 | 260 | __genl_unregister_mc_group(family, grp); |
2dbba6f7 JB |
261 | } |
262 | ||
482a8524 TG |
263 | /** |
264 | * genl_register_ops - register generic netlink operations | |
265 | * @family: generic netlink family | |
266 | * @ops: operations to be registered | |
267 | * | |
268 | * Registers the specified operations and assigns them to the specified | |
269 | * family. Either a doit or dumpit callback must be specified or the | |
270 | * operation will fail. Only one operation structure per command | |
271 | * identifier may be registered. | |
272 | * | |
273 | * See include/net/genetlink.h for more documenation on the operations | |
274 | * structure. | |
275 | * | |
276 | * Returns 0 on success or a negative error code. | |
277 | */ | |
278 | int genl_register_ops(struct genl_family *family, struct genl_ops *ops) | |
279 | { | |
280 | int err = -EINVAL; | |
281 | ||
282 | if (ops->dumpit == NULL && ops->doit == NULL) | |
283 | goto errout; | |
284 | ||
285 | if (genl_get_cmd(ops->cmd, family)) { | |
286 | err = -EEXIST; | |
287 | goto errout; | |
288 | } | |
289 | ||
334c29a6 | 290 | if (ops->dumpit) |
334c29a6 | 291 | ops->flags |= GENL_CMD_CAP_DUMP; |
48d4ed7a JHS |
292 | if (ops->doit) |
293 | ops->flags |= GENL_CMD_CAP_DO; | |
334c29a6 JHS |
294 | if (ops->policy) |
295 | ops->flags |= GENL_CMD_CAP_HASPOL; | |
296 | ||
482a8524 TG |
297 | genl_lock(); |
298 | list_add_tail(&ops->ops_list, &family->ops_list); | |
299 | genl_unlock(); | |
300 | ||
301 | genl_ctrl_event(CTRL_CMD_NEWOPS, ops); | |
302 | err = 0; | |
303 | errout: | |
304 | return err; | |
305 | } | |
306 | ||
307 | /** | |
308 | * genl_unregister_ops - unregister generic netlink operations | |
309 | * @family: generic netlink family | |
310 | * @ops: operations to be unregistered | |
311 | * | |
312 | * Unregisters the specified operations and unassigns them from the | |
313 | * specified family. The operation blocks until the current message | |
314 | * processing has finished and doesn't start again until the | |
315 | * unregister process has finished. | |
316 | * | |
317 | * Note: It is not necessary to unregister all operations before | |
318 | * unregistering the family, unregistering the family will cause | |
319 | * all assigned operations to be unregistered automatically. | |
320 | * | |
321 | * Returns 0 on success or a negative error code. | |
322 | */ | |
323 | int genl_unregister_ops(struct genl_family *family, struct genl_ops *ops) | |
324 | { | |
325 | struct genl_ops *rc; | |
326 | ||
327 | genl_lock(); | |
328 | list_for_each_entry(rc, &family->ops_list, ops_list) { | |
329 | if (rc == ops) { | |
330 | list_del(&ops->ops_list); | |
331 | genl_unlock(); | |
332 | genl_ctrl_event(CTRL_CMD_DELOPS, ops); | |
333 | return 0; | |
334 | } | |
335 | } | |
336 | genl_unlock(); | |
337 | ||
338 | return -ENOENT; | |
339 | } | |
340 | ||
341 | /** | |
342 | * genl_register_family - register a generic netlink family | |
343 | * @family: generic netlink family | |
344 | * | |
345 | * Registers the specified family after validating it first. Only one | |
346 | * family may be registered with the same family name or identifier. | |
347 | * The family id may equal GENL_ID_GENERATE causing an unique id to | |
348 | * be automatically generated and assigned. | |
349 | * | |
350 | * Return 0 on success or a negative error code. | |
351 | */ | |
352 | int genl_register_family(struct genl_family *family) | |
353 | { | |
354 | int err = -EINVAL; | |
355 | ||
356 | if (family->id && family->id < GENL_MIN_ID) | |
357 | goto errout; | |
358 | ||
359 | if (family->id > GENL_MAX_ID) | |
360 | goto errout; | |
361 | ||
362 | INIT_LIST_HEAD(&family->ops_list); | |
2dbba6f7 | 363 | INIT_LIST_HEAD(&family->mcast_groups); |
482a8524 TG |
364 | |
365 | genl_lock(); | |
366 | ||
367 | if (genl_family_find_byname(family->name)) { | |
368 | err = -EEXIST; | |
369 | goto errout_locked; | |
370 | } | |
371 | ||
372 | if (genl_family_find_byid(family->id)) { | |
373 | err = -EEXIST; | |
374 | goto errout_locked; | |
375 | } | |
376 | ||
482a8524 TG |
377 | if (family->id == GENL_ID_GENERATE) { |
378 | u16 newid = genl_generate_id(); | |
379 | ||
380 | if (!newid) { | |
381 | err = -ENOMEM; | |
382 | goto errout_locked; | |
383 | } | |
384 | ||
385 | family->id = newid; | |
386 | } | |
387 | ||
388 | if (family->maxattr) { | |
389 | family->attrbuf = kmalloc((family->maxattr+1) * | |
390 | sizeof(struct nlattr *), GFP_KERNEL); | |
391 | if (family->attrbuf == NULL) { | |
392 | err = -ENOMEM; | |
e200bd80 | 393 | goto errout_locked; |
482a8524 TG |
394 | } |
395 | } else | |
396 | family->attrbuf = NULL; | |
397 | ||
398 | list_add_tail(&family->family_list, genl_family_chain(family->id)); | |
399 | genl_unlock(); | |
400 | ||
401 | genl_ctrl_event(CTRL_CMD_NEWFAMILY, family); | |
402 | ||
403 | return 0; | |
404 | ||
405 | errout_locked: | |
406 | genl_unlock(); | |
407 | errout: | |
408 | return err; | |
409 | } | |
410 | ||
a7b11d73 MM |
411 | /** |
412 | * genl_register_family_with_ops - register a generic netlink family | |
413 | * @family: generic netlink family | |
414 | * @ops: operations to be registered | |
415 | * @n_ops: number of elements to register | |
416 | * | |
417 | * Registers the specified family and operations from the specified table. | |
418 | * Only one family may be registered with the same family name or identifier. | |
419 | * | |
420 | * The family id may equal GENL_ID_GENERATE causing an unique id to | |
421 | * be automatically generated and assigned. | |
422 | * | |
423 | * Either a doit or dumpit callback must be specified for every registered | |
424 | * operation or the function will fail. Only one operation structure per | |
425 | * command identifier may be registered. | |
426 | * | |
427 | * See include/net/genetlink.h for more documenation on the operations | |
428 | * structure. | |
429 | * | |
430 | * This is equivalent to calling genl_register_family() followed by | |
431 | * genl_register_ops() for every operation entry in the table taking | |
432 | * care to unregister the family on error path. | |
433 | * | |
434 | * Return 0 on success or a negative error code. | |
435 | */ | |
436 | int genl_register_family_with_ops(struct genl_family *family, | |
437 | struct genl_ops *ops, size_t n_ops) | |
438 | { | |
439 | int err, i; | |
440 | ||
441 | err = genl_register_family(family); | |
442 | if (err) | |
443 | return err; | |
444 | ||
445 | for (i = 0; i < n_ops; ++i, ++ops) { | |
446 | err = genl_register_ops(family, ops); | |
447 | if (err) | |
448 | goto err_out; | |
449 | } | |
450 | return 0; | |
451 | err_out: | |
452 | genl_unregister_family(family); | |
453 | return err; | |
454 | } | |
455 | EXPORT_SYMBOL(genl_register_family_with_ops); | |
456 | ||
482a8524 TG |
457 | /** |
458 | * genl_unregister_family - unregister generic netlink family | |
459 | * @family: generic netlink family | |
460 | * | |
461 | * Unregisters the specified family. | |
462 | * | |
463 | * Returns 0 on success or a negative error code. | |
464 | */ | |
465 | int genl_unregister_family(struct genl_family *family) | |
466 | { | |
467 | struct genl_family *rc; | |
468 | ||
469 | genl_lock(); | |
470 | ||
910d6c32 PE |
471 | genl_unregister_mc_groups(family); |
472 | ||
482a8524 TG |
473 | list_for_each_entry(rc, genl_family_chain(family->id), family_list) { |
474 | if (family->id != rc->id || strcmp(rc->name, family->name)) | |
475 | continue; | |
476 | ||
477 | list_del(&rc->family_list); | |
478 | INIT_LIST_HEAD(&family->ops_list); | |
479 | genl_unlock(); | |
480 | ||
482a8524 TG |
481 | kfree(family->attrbuf); |
482 | genl_ctrl_event(CTRL_CMD_DELFAMILY, family); | |
483 | return 0; | |
484 | } | |
485 | ||
486 | genl_unlock(); | |
487 | ||
488 | return -ENOENT; | |
489 | } | |
490 | ||
1d00a4eb | 491 | static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) |
482a8524 TG |
492 | { |
493 | struct genl_ops *ops; | |
494 | struct genl_family *family; | |
134e6375 | 495 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
496 | struct genl_info info; |
497 | struct genlmsghdr *hdr = nlmsg_data(nlh); | |
1d00a4eb | 498 | int hdrlen, err; |
482a8524 | 499 | |
746fac4d | 500 | family = genl_family_find_byid(nlh->nlmsg_type); |
1d00a4eb TG |
501 | if (family == NULL) |
502 | return -ENOENT; | |
482a8524 | 503 | |
134e6375 JB |
504 | /* this family doesn't exist in this netns */ |
505 | if (!family->netnsok && !net_eq(net, &init_net)) | |
506 | return -ENOENT; | |
507 | ||
482a8524 TG |
508 | hdrlen = GENL_HDRLEN + family->hdrsize; |
509 | if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) | |
1d00a4eb | 510 | return -EINVAL; |
482a8524 TG |
511 | |
512 | ops = genl_get_cmd(hdr->cmd, family); | |
1d00a4eb TG |
513 | if (ops == NULL) |
514 | return -EOPNOTSUPP; | |
482a8524 | 515 | |
1d00a4eb TG |
516 | if ((ops->flags & GENL_ADMIN_PERM) && |
517 | security_netlink_recv(skb, CAP_NET_ADMIN)) | |
518 | return -EPERM; | |
482a8524 TG |
519 | |
520 | if (nlh->nlmsg_flags & NLM_F_DUMP) { | |
1d00a4eb TG |
521 | if (ops->dumpit == NULL) |
522 | return -EOPNOTSUPP; | |
482a8524 | 523 | |
6d1a3fb5 | 524 | genl_unlock(); |
134e6375 | 525 | err = netlink_dump_start(net->genl_sock, skb, nlh, |
6d1a3fb5 PM |
526 | ops->dumpit, ops->done); |
527 | genl_lock(); | |
528 | return err; | |
482a8524 TG |
529 | } |
530 | ||
1d00a4eb TG |
531 | if (ops->doit == NULL) |
532 | return -EOPNOTSUPP; | |
482a8524 TG |
533 | |
534 | if (family->attrbuf) { | |
535 | err = nlmsg_parse(nlh, hdrlen, family->attrbuf, family->maxattr, | |
536 | ops->policy); | |
537 | if (err < 0) | |
1d00a4eb | 538 | return err; |
482a8524 TG |
539 | } |
540 | ||
541 | info.snd_seq = nlh->nlmsg_seq; | |
542 | info.snd_pid = NETLINK_CB(skb).pid; | |
543 | info.nlhdr = nlh; | |
544 | info.genlhdr = nlmsg_data(nlh); | |
545 | info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN; | |
546 | info.attrs = family->attrbuf; | |
134e6375 | 547 | genl_info_net_set(&info, net); |
482a8524 | 548 | |
1d00a4eb | 549 | return ops->doit(skb, &info); |
482a8524 TG |
550 | } |
551 | ||
cd40b7d3 | 552 | static void genl_rcv(struct sk_buff *skb) |
482a8524 | 553 | { |
cd40b7d3 DL |
554 | genl_lock(); |
555 | netlink_rcv_skb(skb, &genl_rcv_msg); | |
556 | genl_unlock(); | |
482a8524 TG |
557 | } |
558 | ||
559 | /************************************************************************** | |
560 | * Controller | |
561 | **************************************************************************/ | |
562 | ||
17c157c8 TG |
563 | static struct genl_family genl_ctrl = { |
564 | .id = GENL_ID_CTRL, | |
565 | .name = "nlctrl", | |
334c29a6 | 566 | .version = 0x2, |
17c157c8 | 567 | .maxattr = CTRL_ATTR_MAX, |
134e6375 | 568 | .netnsok = true, |
17c157c8 TG |
569 | }; |
570 | ||
482a8524 TG |
571 | static int ctrl_fill_info(struct genl_family *family, u32 pid, u32 seq, |
572 | u32 flags, struct sk_buff *skb, u8 cmd) | |
573 | { | |
574 | void *hdr; | |
575 | ||
17c157c8 | 576 | hdr = genlmsg_put(skb, pid, seq, &genl_ctrl, flags, cmd); |
482a8524 TG |
577 | if (hdr == NULL) |
578 | return -1; | |
579 | ||
580 | NLA_PUT_STRING(skb, CTRL_ATTR_FAMILY_NAME, family->name); | |
581 | NLA_PUT_U16(skb, CTRL_ATTR_FAMILY_ID, family->id); | |
eb328111 TG |
582 | NLA_PUT_U32(skb, CTRL_ATTR_VERSION, family->version); |
583 | NLA_PUT_U32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize); | |
584 | NLA_PUT_U32(skb, CTRL_ATTR_MAXATTR, family->maxattr); | |
585 | ||
e94ef682 TG |
586 | if (!list_empty(&family->ops_list)) { |
587 | struct nlattr *nla_ops; | |
588 | struct genl_ops *ops; | |
589 | int idx = 1; | |
eb328111 | 590 | |
e94ef682 TG |
591 | nla_ops = nla_nest_start(skb, CTRL_ATTR_OPS); |
592 | if (nla_ops == NULL) | |
eb328111 TG |
593 | goto nla_put_failure; |
594 | ||
e94ef682 TG |
595 | list_for_each_entry(ops, &family->ops_list, ops_list) { |
596 | struct nlattr *nest; | |
eb328111 | 597 | |
e94ef682 TG |
598 | nest = nla_nest_start(skb, idx++); |
599 | if (nest == NULL) | |
600 | goto nla_put_failure; | |
eb328111 | 601 | |
e94ef682 TG |
602 | NLA_PUT_U32(skb, CTRL_ATTR_OP_ID, ops->cmd); |
603 | NLA_PUT_U32(skb, CTRL_ATTR_OP_FLAGS, ops->flags); | |
eb328111 | 604 | |
e94ef682 TG |
605 | nla_nest_end(skb, nest); |
606 | } | |
607 | ||
608 | nla_nest_end(skb, nla_ops); | |
609 | } | |
482a8524 | 610 | |
2dbba6f7 JB |
611 | if (!list_empty(&family->mcast_groups)) { |
612 | struct genl_multicast_group *grp; | |
613 | struct nlattr *nla_grps; | |
614 | int idx = 1; | |
615 | ||
616 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
617 | if (nla_grps == NULL) | |
618 | goto nla_put_failure; | |
619 | ||
620 | list_for_each_entry(grp, &family->mcast_groups, list) { | |
621 | struct nlattr *nest; | |
622 | ||
623 | nest = nla_nest_start(skb, idx++); | |
624 | if (nest == NULL) | |
625 | goto nla_put_failure; | |
626 | ||
627 | NLA_PUT_U32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id); | |
628 | NLA_PUT_STRING(skb, CTRL_ATTR_MCAST_GRP_NAME, | |
629 | grp->name); | |
630 | ||
631 | nla_nest_end(skb, nest); | |
632 | } | |
633 | nla_nest_end(skb, nla_grps); | |
634 | } | |
635 | ||
636 | return genlmsg_end(skb, hdr); | |
637 | ||
638 | nla_put_failure: | |
bc3ed28c TG |
639 | genlmsg_cancel(skb, hdr); |
640 | return -EMSGSIZE; | |
2dbba6f7 JB |
641 | } |
642 | ||
643 | static int ctrl_fill_mcgrp_info(struct genl_multicast_group *grp, u32 pid, | |
644 | u32 seq, u32 flags, struct sk_buff *skb, | |
645 | u8 cmd) | |
646 | { | |
647 | void *hdr; | |
648 | struct nlattr *nla_grps; | |
649 | struct nlattr *nest; | |
650 | ||
651 | hdr = genlmsg_put(skb, pid, seq, &genl_ctrl, flags, cmd); | |
652 | if (hdr == NULL) | |
653 | return -1; | |
654 | ||
655 | NLA_PUT_STRING(skb, CTRL_ATTR_FAMILY_NAME, grp->family->name); | |
656 | NLA_PUT_U16(skb, CTRL_ATTR_FAMILY_ID, grp->family->id); | |
657 | ||
658 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
659 | if (nla_grps == NULL) | |
660 | goto nla_put_failure; | |
661 | ||
662 | nest = nla_nest_start(skb, 1); | |
663 | if (nest == NULL) | |
664 | goto nla_put_failure; | |
665 | ||
666 | NLA_PUT_U32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id); | |
667 | NLA_PUT_STRING(skb, CTRL_ATTR_MCAST_GRP_NAME, | |
668 | grp->name); | |
669 | ||
670 | nla_nest_end(skb, nest); | |
671 | nla_nest_end(skb, nla_grps); | |
672 | ||
482a8524 TG |
673 | return genlmsg_end(skb, hdr); |
674 | ||
675 | nla_put_failure: | |
bc3ed28c TG |
676 | genlmsg_cancel(skb, hdr); |
677 | return -EMSGSIZE; | |
482a8524 TG |
678 | } |
679 | ||
680 | static int ctrl_dumpfamily(struct sk_buff *skb, struct netlink_callback *cb) | |
681 | { | |
682 | ||
683 | int i, n = 0; | |
684 | struct genl_family *rt; | |
134e6375 | 685 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
686 | int chains_to_skip = cb->args[0]; |
687 | int fams_to_skip = cb->args[1]; | |
688 | ||
689 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) { | |
690 | if (i < chains_to_skip) | |
691 | continue; | |
692 | n = 0; | |
693 | list_for_each_entry(rt, genl_family_chain(i), family_list) { | |
134e6375 JB |
694 | if (!rt->netnsok && !net_eq(net, &init_net)) |
695 | continue; | |
482a8524 TG |
696 | if (++n < fams_to_skip) |
697 | continue; | |
698 | if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).pid, | |
699 | cb->nlh->nlmsg_seq, NLM_F_MULTI, | |
700 | skb, CTRL_CMD_NEWFAMILY) < 0) | |
701 | goto errout; | |
702 | } | |
703 | ||
704 | fams_to_skip = 0; | |
705 | } | |
706 | ||
707 | errout: | |
708 | cb->args[0] = i; | |
709 | cb->args[1] = n; | |
710 | ||
711 | return skb->len; | |
712 | } | |
713 | ||
2dbba6f7 JB |
714 | static struct sk_buff *ctrl_build_family_msg(struct genl_family *family, |
715 | u32 pid, int seq, u8 cmd) | |
482a8524 TG |
716 | { |
717 | struct sk_buff *skb; | |
718 | int err; | |
719 | ||
339bf98f | 720 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); |
482a8524 TG |
721 | if (skb == NULL) |
722 | return ERR_PTR(-ENOBUFS); | |
723 | ||
724 | err = ctrl_fill_info(family, pid, seq, 0, skb, cmd); | |
725 | if (err < 0) { | |
726 | nlmsg_free(skb); | |
727 | return ERR_PTR(err); | |
728 | } | |
729 | ||
730 | return skb; | |
731 | } | |
732 | ||
2dbba6f7 JB |
733 | static struct sk_buff *ctrl_build_mcgrp_msg(struct genl_multicast_group *grp, |
734 | u32 pid, int seq, u8 cmd) | |
735 | { | |
736 | struct sk_buff *skb; | |
737 | int err; | |
738 | ||
739 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); | |
740 | if (skb == NULL) | |
741 | return ERR_PTR(-ENOBUFS); | |
742 | ||
743 | err = ctrl_fill_mcgrp_info(grp, pid, seq, 0, skb, cmd); | |
744 | if (err < 0) { | |
745 | nlmsg_free(skb); | |
746 | return ERR_PTR(err); | |
747 | } | |
748 | ||
749 | return skb; | |
750 | } | |
751 | ||
ef7c79ed | 752 | static const struct nla_policy ctrl_policy[CTRL_ATTR_MAX+1] = { |
482a8524 | 753 | [CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 }, |
5176f91e TG |
754 | [CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING, |
755 | .len = GENL_NAMSIZ - 1 }, | |
482a8524 TG |
756 | }; |
757 | ||
758 | static int ctrl_getfamily(struct sk_buff *skb, struct genl_info *info) | |
759 | { | |
760 | struct sk_buff *msg; | |
761 | struct genl_family *res = NULL; | |
762 | int err = -EINVAL; | |
763 | ||
764 | if (info->attrs[CTRL_ATTR_FAMILY_ID]) { | |
765 | u16 id = nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]); | |
766 | res = genl_family_find_byid(id); | |
134e6375 | 767 | err = -ENOENT; |
482a8524 TG |
768 | } |
769 | ||
770 | if (info->attrs[CTRL_ATTR_FAMILY_NAME]) { | |
5176f91e | 771 | char *name; |
482a8524 | 772 | |
5176f91e | 773 | name = nla_data(info->attrs[CTRL_ATTR_FAMILY_NAME]); |
482a8524 | 774 | res = genl_family_find_byname(name); |
134e6375 | 775 | err = -ENOENT; |
482a8524 TG |
776 | } |
777 | ||
134e6375 JB |
778 | if (res == NULL) |
779 | return err; | |
780 | ||
781 | if (!res->netnsok && !net_eq(genl_info_net(info), &init_net)) { | |
782 | /* family doesn't exist here */ | |
783 | return -ENOENT; | |
482a8524 TG |
784 | } |
785 | ||
2dbba6f7 JB |
786 | msg = ctrl_build_family_msg(res, info->snd_pid, info->snd_seq, |
787 | CTRL_CMD_NEWFAMILY); | |
134e6375 JB |
788 | if (IS_ERR(msg)) |
789 | return PTR_ERR(msg); | |
482a8524 | 790 | |
134e6375 | 791 | return genlmsg_reply(msg, info); |
482a8524 TG |
792 | } |
793 | ||
794 | static int genl_ctrl_event(int event, void *data) | |
795 | { | |
796 | struct sk_buff *msg; | |
134e6375 JB |
797 | struct genl_family *family; |
798 | struct genl_multicast_group *grp; | |
482a8524 | 799 | |
134e6375 JB |
800 | /* genl is still initialising */ |
801 | if (!init_net.genl_sock) | |
482a8524 TG |
802 | return 0; |
803 | ||
804 | switch (event) { | |
805 | case CTRL_CMD_NEWFAMILY: | |
806 | case CTRL_CMD_DELFAMILY: | |
134e6375 JB |
807 | family = data; |
808 | msg = ctrl_build_family_msg(family, 0, 0, event); | |
2dbba6f7 JB |
809 | break; |
810 | case CTRL_CMD_NEWMCAST_GRP: | |
811 | case CTRL_CMD_DELMCAST_GRP: | |
134e6375 JB |
812 | grp = data; |
813 | family = grp->family; | |
2dbba6f7 | 814 | msg = ctrl_build_mcgrp_msg(data, 0, 0, event); |
482a8524 | 815 | break; |
134e6375 JB |
816 | default: |
817 | return -EINVAL; | |
818 | } | |
819 | ||
820 | if (IS_ERR(msg)) | |
821 | return PTR_ERR(msg); | |
822 | ||
823 | if (!family->netnsok) { | |
824 | genlmsg_multicast_netns(&init_net, msg, 0, | |
825 | GENL_ID_CTRL, GFP_KERNEL); | |
826 | } else { | |
827 | rcu_read_lock(); | |
828 | genlmsg_multicast_allns(msg, 0, GENL_ID_CTRL, GFP_ATOMIC); | |
829 | rcu_read_unlock(); | |
482a8524 TG |
830 | } |
831 | ||
832 | return 0; | |
833 | } | |
834 | ||
835 | static struct genl_ops genl_ctrl_ops = { | |
836 | .cmd = CTRL_CMD_GETFAMILY, | |
837 | .doit = ctrl_getfamily, | |
838 | .dumpit = ctrl_dumpfamily, | |
839 | .policy = ctrl_policy, | |
840 | }; | |
841 | ||
2dbba6f7 JB |
842 | static struct genl_multicast_group notify_grp = { |
843 | .name = "notify", | |
844 | }; | |
845 | ||
134e6375 JB |
846 | static int __net_init genl_pernet_init(struct net *net) |
847 | { | |
848 | /* we'll bump the group number right afterwards */ | |
849 | net->genl_sock = netlink_kernel_create(net, NETLINK_GENERIC, 0, | |
850 | genl_rcv, &genl_mutex, | |
851 | THIS_MODULE); | |
852 | ||
853 | if (!net->genl_sock && net_eq(net, &init_net)) | |
854 | panic("GENL: Cannot initialize generic netlink\n"); | |
855 | ||
856 | if (!net->genl_sock) | |
857 | return -ENOMEM; | |
858 | ||
859 | return 0; | |
860 | } | |
861 | ||
862 | static void __net_exit genl_pernet_exit(struct net *net) | |
863 | { | |
864 | netlink_kernel_release(net->genl_sock); | |
865 | net->genl_sock = NULL; | |
866 | } | |
867 | ||
868 | static struct pernet_operations genl_pernet_ops = { | |
869 | .init = genl_pernet_init, | |
870 | .exit = genl_pernet_exit, | |
871 | }; | |
872 | ||
482a8524 TG |
873 | static int __init genl_init(void) |
874 | { | |
875 | int i, err; | |
876 | ||
877 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) | |
878 | INIT_LIST_HEAD(&family_ht[i]); | |
879 | ||
880 | err = genl_register_family(&genl_ctrl); | |
881 | if (err < 0) | |
134e6375 | 882 | goto problem; |
482a8524 TG |
883 | |
884 | err = genl_register_ops(&genl_ctrl, &genl_ctrl_ops); | |
885 | if (err < 0) | |
134e6375 | 886 | goto problem; |
482a8524 TG |
887 | |
888 | netlink_set_nonroot(NETLINK_GENERIC, NL_NONROOT_RECV); | |
2dbba6f7 | 889 | |
134e6375 JB |
890 | err = register_pernet_subsys(&genl_pernet_ops); |
891 | if (err) | |
892 | goto problem; | |
482a8524 | 893 | |
2dbba6f7 JB |
894 | err = genl_register_mc_group(&genl_ctrl, ¬ify_grp); |
895 | if (err < 0) | |
134e6375 | 896 | goto problem; |
2dbba6f7 | 897 | |
482a8524 TG |
898 | return 0; |
899 | ||
134e6375 | 900 | problem: |
482a8524 | 901 | panic("GENL: Cannot register controller: %d\n", err); |
482a8524 TG |
902 | } |
903 | ||
904 | subsys_initcall(genl_init); | |
905 | ||
482a8524 TG |
906 | EXPORT_SYMBOL(genl_register_ops); |
907 | EXPORT_SYMBOL(genl_unregister_ops); | |
908 | EXPORT_SYMBOL(genl_register_family); | |
909 | EXPORT_SYMBOL(genl_unregister_family); | |
134e6375 JB |
910 | |
911 | static int genlmsg_mcast(struct sk_buff *skb, u32 pid, unsigned long group, | |
912 | gfp_t flags) | |
913 | { | |
914 | struct sk_buff *tmp; | |
915 | struct net *net, *prev = NULL; | |
916 | int err; | |
917 | ||
918 | for_each_net_rcu(net) { | |
919 | if (prev) { | |
920 | tmp = skb_clone(skb, flags); | |
921 | if (!tmp) { | |
922 | err = -ENOMEM; | |
923 | goto error; | |
924 | } | |
925 | err = nlmsg_multicast(prev->genl_sock, tmp, | |
926 | pid, group, flags); | |
927 | if (err) | |
928 | goto error; | |
929 | } | |
930 | ||
931 | prev = net; | |
932 | } | |
933 | ||
934 | return nlmsg_multicast(prev->genl_sock, skb, pid, group, flags); | |
935 | error: | |
936 | kfree_skb(skb); | |
937 | return err; | |
938 | } | |
939 | ||
940 | int genlmsg_multicast_allns(struct sk_buff *skb, u32 pid, unsigned int group, | |
941 | gfp_t flags) | |
942 | { | |
943 | return genlmsg_mcast(skb, pid, group, flags); | |
944 | } | |
945 | EXPORT_SYMBOL(genlmsg_multicast_allns); |