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; | |
b1f57195 | 139 | int err = 0; |
2dbba6f7 JB |
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 | ||
d136f1bd | 179 | netlink_table_grab(); |
134e6375 JB |
180 | rcu_read_lock(); |
181 | for_each_net_rcu(net) { | |
d136f1bd | 182 | err = __netlink_change_ngroups(net->genl_sock, |
134e6375 JB |
183 | mc_groups_longs * BITS_PER_LONG); |
184 | if (err) { | |
185 | /* | |
186 | * No need to roll back, can only fail if | |
187 | * memory allocation fails and then the | |
188 | * number of _possible_ groups has been | |
189 | * increased on some sockets which is ok. | |
190 | */ | |
191 | rcu_read_unlock(); | |
d136f1bd | 192 | netlink_table_ungrab(); |
134e6375 JB |
193 | goto out; |
194 | } | |
195 | } | |
196 | rcu_read_unlock(); | |
d136f1bd | 197 | netlink_table_ungrab(); |
134e6375 JB |
198 | } else { |
199 | err = netlink_change_ngroups(init_net.genl_sock, | |
200 | mc_groups_longs * BITS_PER_LONG); | |
201 | if (err) | |
202 | goto out; | |
203 | } | |
2dbba6f7 JB |
204 | |
205 | grp->id = id; | |
206 | set_bit(id, mc_groups); | |
207 | list_add_tail(&grp->list, &family->mcast_groups); | |
208 | grp->family = family; | |
209 | ||
210 | genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, grp); | |
211 | out: | |
212 | genl_unlock(); | |
79d310d0 | 213 | return err; |
2dbba6f7 JB |
214 | } |
215 | EXPORT_SYMBOL(genl_register_mc_group); | |
216 | ||
79dc4386 TG |
217 | static void __genl_unregister_mc_group(struct genl_family *family, |
218 | struct genl_multicast_group *grp) | |
219 | { | |
134e6375 | 220 | struct net *net; |
79dc4386 | 221 | BUG_ON(grp->family != family); |
134e6375 | 222 | |
b8273570 | 223 | netlink_table_grab(); |
134e6375 JB |
224 | rcu_read_lock(); |
225 | for_each_net_rcu(net) | |
b8273570 | 226 | __netlink_clear_multicast_users(net->genl_sock, grp->id); |
134e6375 | 227 | rcu_read_unlock(); |
b8273570 | 228 | netlink_table_ungrab(); |
134e6375 | 229 | |
79dc4386 TG |
230 | clear_bit(grp->id, mc_groups); |
231 | list_del(&grp->list); | |
232 | genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, grp); | |
233 | grp->id = 0; | |
234 | grp->family = NULL; | |
235 | } | |
236 | ||
2dbba6f7 JB |
237 | /** |
238 | * genl_unregister_mc_group - unregister a multicast group | |
239 | * | |
240 | * Unregisters the specified multicast group and notifies userspace | |
241 | * about it. All current listeners on the group are removed. | |
242 | * | |
243 | * Note: It is not necessary to unregister all multicast groups before | |
244 | * unregistering the family, unregistering the family will cause | |
245 | * all assigned multicast groups to be unregistered automatically. | |
246 | * | |
247 | * @family: Generic netlink family the group belongs to. | |
248 | * @grp: The group to unregister, must have been registered successfully | |
249 | * previously. | |
250 | */ | |
251 | void genl_unregister_mc_group(struct genl_family *family, | |
252 | struct genl_multicast_group *grp) | |
253 | { | |
2dbba6f7 | 254 | genl_lock(); |
79dc4386 | 255 | __genl_unregister_mc_group(family, grp); |
2dbba6f7 JB |
256 | genl_unlock(); |
257 | } | |
3efb40c2 | 258 | EXPORT_SYMBOL(genl_unregister_mc_group); |
2dbba6f7 JB |
259 | |
260 | static void genl_unregister_mc_groups(struct genl_family *family) | |
261 | { | |
262 | struct genl_multicast_group *grp, *tmp; | |
263 | ||
264 | list_for_each_entry_safe(grp, tmp, &family->mcast_groups, list) | |
79dc4386 | 265 | __genl_unregister_mc_group(family, grp); |
2dbba6f7 JB |
266 | } |
267 | ||
482a8524 TG |
268 | /** |
269 | * genl_register_ops - register generic netlink operations | |
270 | * @family: generic netlink family | |
271 | * @ops: operations to be registered | |
272 | * | |
273 | * Registers the specified operations and assigns them to the specified | |
274 | * family. Either a doit or dumpit callback must be specified or the | |
275 | * operation will fail. Only one operation structure per command | |
276 | * identifier may be registered. | |
277 | * | |
278 | * See include/net/genetlink.h for more documenation on the operations | |
279 | * structure. | |
280 | * | |
281 | * Returns 0 on success or a negative error code. | |
282 | */ | |
283 | int genl_register_ops(struct genl_family *family, struct genl_ops *ops) | |
284 | { | |
285 | int err = -EINVAL; | |
286 | ||
287 | if (ops->dumpit == NULL && ops->doit == NULL) | |
288 | goto errout; | |
289 | ||
290 | if (genl_get_cmd(ops->cmd, family)) { | |
291 | err = -EEXIST; | |
292 | goto errout; | |
293 | } | |
294 | ||
334c29a6 | 295 | if (ops->dumpit) |
334c29a6 | 296 | ops->flags |= GENL_CMD_CAP_DUMP; |
48d4ed7a JHS |
297 | if (ops->doit) |
298 | ops->flags |= GENL_CMD_CAP_DO; | |
334c29a6 JHS |
299 | if (ops->policy) |
300 | ops->flags |= GENL_CMD_CAP_HASPOL; | |
301 | ||
482a8524 TG |
302 | genl_lock(); |
303 | list_add_tail(&ops->ops_list, &family->ops_list); | |
304 | genl_unlock(); | |
305 | ||
306 | genl_ctrl_event(CTRL_CMD_NEWOPS, ops); | |
307 | err = 0; | |
308 | errout: | |
309 | return err; | |
310 | } | |
311 | ||
312 | /** | |
313 | * genl_unregister_ops - unregister generic netlink operations | |
314 | * @family: generic netlink family | |
315 | * @ops: operations to be unregistered | |
316 | * | |
317 | * Unregisters the specified operations and unassigns them from the | |
318 | * specified family. The operation blocks until the current message | |
319 | * processing has finished and doesn't start again until the | |
320 | * unregister process has finished. | |
321 | * | |
322 | * Note: It is not necessary to unregister all operations before | |
323 | * unregistering the family, unregistering the family will cause | |
324 | * all assigned operations to be unregistered automatically. | |
325 | * | |
326 | * Returns 0 on success or a negative error code. | |
327 | */ | |
328 | int genl_unregister_ops(struct genl_family *family, struct genl_ops *ops) | |
329 | { | |
330 | struct genl_ops *rc; | |
331 | ||
332 | genl_lock(); | |
333 | list_for_each_entry(rc, &family->ops_list, ops_list) { | |
334 | if (rc == ops) { | |
335 | list_del(&ops->ops_list); | |
336 | genl_unlock(); | |
337 | genl_ctrl_event(CTRL_CMD_DELOPS, ops); | |
338 | return 0; | |
339 | } | |
340 | } | |
341 | genl_unlock(); | |
342 | ||
343 | return -ENOENT; | |
344 | } | |
345 | ||
346 | /** | |
347 | * genl_register_family - register a generic netlink family | |
348 | * @family: generic netlink family | |
349 | * | |
350 | * Registers the specified family after validating it first. Only one | |
351 | * family may be registered with the same family name or identifier. | |
352 | * The family id may equal GENL_ID_GENERATE causing an unique id to | |
353 | * be automatically generated and assigned. | |
354 | * | |
355 | * Return 0 on success or a negative error code. | |
356 | */ | |
357 | int genl_register_family(struct genl_family *family) | |
358 | { | |
359 | int err = -EINVAL; | |
360 | ||
361 | if (family->id && family->id < GENL_MIN_ID) | |
362 | goto errout; | |
363 | ||
364 | if (family->id > GENL_MAX_ID) | |
365 | goto errout; | |
366 | ||
367 | INIT_LIST_HEAD(&family->ops_list); | |
2dbba6f7 | 368 | INIT_LIST_HEAD(&family->mcast_groups); |
482a8524 TG |
369 | |
370 | genl_lock(); | |
371 | ||
372 | if (genl_family_find_byname(family->name)) { | |
373 | err = -EEXIST; | |
374 | goto errout_locked; | |
375 | } | |
376 | ||
377 | if (genl_family_find_byid(family->id)) { | |
378 | err = -EEXIST; | |
379 | goto errout_locked; | |
380 | } | |
381 | ||
482a8524 TG |
382 | if (family->id == GENL_ID_GENERATE) { |
383 | u16 newid = genl_generate_id(); | |
384 | ||
385 | if (!newid) { | |
386 | err = -ENOMEM; | |
387 | goto errout_locked; | |
388 | } | |
389 | ||
390 | family->id = newid; | |
391 | } | |
392 | ||
393 | if (family->maxattr) { | |
394 | family->attrbuf = kmalloc((family->maxattr+1) * | |
395 | sizeof(struct nlattr *), GFP_KERNEL); | |
396 | if (family->attrbuf == NULL) { | |
397 | err = -ENOMEM; | |
e200bd80 | 398 | goto errout_locked; |
482a8524 TG |
399 | } |
400 | } else | |
401 | family->attrbuf = NULL; | |
402 | ||
403 | list_add_tail(&family->family_list, genl_family_chain(family->id)); | |
404 | genl_unlock(); | |
405 | ||
406 | genl_ctrl_event(CTRL_CMD_NEWFAMILY, family); | |
407 | ||
408 | return 0; | |
409 | ||
410 | errout_locked: | |
411 | genl_unlock(); | |
412 | errout: | |
413 | return err; | |
414 | } | |
415 | ||
a7b11d73 MM |
416 | /** |
417 | * genl_register_family_with_ops - register a generic netlink family | |
418 | * @family: generic netlink family | |
419 | * @ops: operations to be registered | |
420 | * @n_ops: number of elements to register | |
421 | * | |
422 | * Registers the specified family and operations from the specified table. | |
423 | * Only one family may be registered with the same family name or identifier. | |
424 | * | |
425 | * The family id may equal GENL_ID_GENERATE causing an unique id to | |
426 | * be automatically generated and assigned. | |
427 | * | |
428 | * Either a doit or dumpit callback must be specified for every registered | |
429 | * operation or the function will fail. Only one operation structure per | |
430 | * command identifier may be registered. | |
431 | * | |
432 | * See include/net/genetlink.h for more documenation on the operations | |
433 | * structure. | |
434 | * | |
435 | * This is equivalent to calling genl_register_family() followed by | |
436 | * genl_register_ops() for every operation entry in the table taking | |
437 | * care to unregister the family on error path. | |
438 | * | |
439 | * Return 0 on success or a negative error code. | |
440 | */ | |
441 | int genl_register_family_with_ops(struct genl_family *family, | |
442 | struct genl_ops *ops, size_t n_ops) | |
443 | { | |
444 | int err, i; | |
445 | ||
446 | err = genl_register_family(family); | |
447 | if (err) | |
448 | return err; | |
449 | ||
450 | for (i = 0; i < n_ops; ++i, ++ops) { | |
451 | err = genl_register_ops(family, ops); | |
452 | if (err) | |
453 | goto err_out; | |
454 | } | |
455 | return 0; | |
456 | err_out: | |
457 | genl_unregister_family(family); | |
458 | return err; | |
459 | } | |
460 | EXPORT_SYMBOL(genl_register_family_with_ops); | |
461 | ||
482a8524 TG |
462 | /** |
463 | * genl_unregister_family - unregister generic netlink family | |
464 | * @family: generic netlink family | |
465 | * | |
466 | * Unregisters the specified family. | |
467 | * | |
468 | * Returns 0 on success or a negative error code. | |
469 | */ | |
470 | int genl_unregister_family(struct genl_family *family) | |
471 | { | |
472 | struct genl_family *rc; | |
473 | ||
474 | genl_lock(); | |
475 | ||
910d6c32 PE |
476 | genl_unregister_mc_groups(family); |
477 | ||
482a8524 TG |
478 | list_for_each_entry(rc, genl_family_chain(family->id), family_list) { |
479 | if (family->id != rc->id || strcmp(rc->name, family->name)) | |
480 | continue; | |
481 | ||
482 | list_del(&rc->family_list); | |
483 | INIT_LIST_HEAD(&family->ops_list); | |
484 | genl_unlock(); | |
485 | ||
482a8524 TG |
486 | kfree(family->attrbuf); |
487 | genl_ctrl_event(CTRL_CMD_DELFAMILY, family); | |
488 | return 0; | |
489 | } | |
490 | ||
491 | genl_unlock(); | |
492 | ||
493 | return -ENOENT; | |
494 | } | |
495 | ||
1d00a4eb | 496 | static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) |
482a8524 TG |
497 | { |
498 | struct genl_ops *ops; | |
499 | struct genl_family *family; | |
134e6375 | 500 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
501 | struct genl_info info; |
502 | struct genlmsghdr *hdr = nlmsg_data(nlh); | |
1d00a4eb | 503 | int hdrlen, err; |
482a8524 | 504 | |
746fac4d | 505 | family = genl_family_find_byid(nlh->nlmsg_type); |
1d00a4eb TG |
506 | if (family == NULL) |
507 | return -ENOENT; | |
482a8524 | 508 | |
134e6375 JB |
509 | /* this family doesn't exist in this netns */ |
510 | if (!family->netnsok && !net_eq(net, &init_net)) | |
511 | return -ENOENT; | |
512 | ||
482a8524 TG |
513 | hdrlen = GENL_HDRLEN + family->hdrsize; |
514 | if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) | |
1d00a4eb | 515 | return -EINVAL; |
482a8524 TG |
516 | |
517 | ops = genl_get_cmd(hdr->cmd, family); | |
1d00a4eb TG |
518 | if (ops == NULL) |
519 | return -EOPNOTSUPP; | |
482a8524 | 520 | |
1d00a4eb TG |
521 | if ((ops->flags & GENL_ADMIN_PERM) && |
522 | security_netlink_recv(skb, CAP_NET_ADMIN)) | |
523 | return -EPERM; | |
482a8524 TG |
524 | |
525 | if (nlh->nlmsg_flags & NLM_F_DUMP) { | |
1d00a4eb TG |
526 | if (ops->dumpit == NULL) |
527 | return -EOPNOTSUPP; | |
482a8524 | 528 | |
6d1a3fb5 | 529 | genl_unlock(); |
134e6375 | 530 | err = netlink_dump_start(net->genl_sock, skb, nlh, |
6d1a3fb5 PM |
531 | ops->dumpit, ops->done); |
532 | genl_lock(); | |
533 | return err; | |
482a8524 TG |
534 | } |
535 | ||
1d00a4eb TG |
536 | if (ops->doit == NULL) |
537 | return -EOPNOTSUPP; | |
482a8524 TG |
538 | |
539 | if (family->attrbuf) { | |
540 | err = nlmsg_parse(nlh, hdrlen, family->attrbuf, family->maxattr, | |
541 | ops->policy); | |
542 | if (err < 0) | |
1d00a4eb | 543 | return err; |
482a8524 TG |
544 | } |
545 | ||
546 | info.snd_seq = nlh->nlmsg_seq; | |
547 | info.snd_pid = NETLINK_CB(skb).pid; | |
548 | info.nlhdr = nlh; | |
549 | info.genlhdr = nlmsg_data(nlh); | |
550 | info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN; | |
551 | info.attrs = family->attrbuf; | |
134e6375 | 552 | genl_info_net_set(&info, net); |
482a8524 | 553 | |
1d00a4eb | 554 | return ops->doit(skb, &info); |
482a8524 TG |
555 | } |
556 | ||
cd40b7d3 | 557 | static void genl_rcv(struct sk_buff *skb) |
482a8524 | 558 | { |
cd40b7d3 DL |
559 | genl_lock(); |
560 | netlink_rcv_skb(skb, &genl_rcv_msg); | |
561 | genl_unlock(); | |
482a8524 TG |
562 | } |
563 | ||
564 | /************************************************************************** | |
565 | * Controller | |
566 | **************************************************************************/ | |
567 | ||
17c157c8 TG |
568 | static struct genl_family genl_ctrl = { |
569 | .id = GENL_ID_CTRL, | |
570 | .name = "nlctrl", | |
334c29a6 | 571 | .version = 0x2, |
17c157c8 | 572 | .maxattr = CTRL_ATTR_MAX, |
134e6375 | 573 | .netnsok = true, |
17c157c8 TG |
574 | }; |
575 | ||
482a8524 TG |
576 | static int ctrl_fill_info(struct genl_family *family, u32 pid, u32 seq, |
577 | u32 flags, struct sk_buff *skb, u8 cmd) | |
578 | { | |
579 | void *hdr; | |
580 | ||
17c157c8 | 581 | hdr = genlmsg_put(skb, pid, seq, &genl_ctrl, flags, cmd); |
482a8524 TG |
582 | if (hdr == NULL) |
583 | return -1; | |
584 | ||
585 | NLA_PUT_STRING(skb, CTRL_ATTR_FAMILY_NAME, family->name); | |
586 | NLA_PUT_U16(skb, CTRL_ATTR_FAMILY_ID, family->id); | |
eb328111 TG |
587 | NLA_PUT_U32(skb, CTRL_ATTR_VERSION, family->version); |
588 | NLA_PUT_U32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize); | |
589 | NLA_PUT_U32(skb, CTRL_ATTR_MAXATTR, family->maxattr); | |
590 | ||
e94ef682 TG |
591 | if (!list_empty(&family->ops_list)) { |
592 | struct nlattr *nla_ops; | |
593 | struct genl_ops *ops; | |
594 | int idx = 1; | |
eb328111 | 595 | |
e94ef682 TG |
596 | nla_ops = nla_nest_start(skb, CTRL_ATTR_OPS); |
597 | if (nla_ops == NULL) | |
eb328111 TG |
598 | goto nla_put_failure; |
599 | ||
e94ef682 TG |
600 | list_for_each_entry(ops, &family->ops_list, ops_list) { |
601 | struct nlattr *nest; | |
eb328111 | 602 | |
e94ef682 TG |
603 | nest = nla_nest_start(skb, idx++); |
604 | if (nest == NULL) | |
605 | goto nla_put_failure; | |
eb328111 | 606 | |
e94ef682 TG |
607 | NLA_PUT_U32(skb, CTRL_ATTR_OP_ID, ops->cmd); |
608 | NLA_PUT_U32(skb, CTRL_ATTR_OP_FLAGS, ops->flags); | |
eb328111 | 609 | |
e94ef682 TG |
610 | nla_nest_end(skb, nest); |
611 | } | |
612 | ||
613 | nla_nest_end(skb, nla_ops); | |
614 | } | |
482a8524 | 615 | |
2dbba6f7 JB |
616 | if (!list_empty(&family->mcast_groups)) { |
617 | struct genl_multicast_group *grp; | |
618 | struct nlattr *nla_grps; | |
619 | int idx = 1; | |
620 | ||
621 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
622 | if (nla_grps == NULL) | |
623 | goto nla_put_failure; | |
624 | ||
625 | list_for_each_entry(grp, &family->mcast_groups, list) { | |
626 | struct nlattr *nest; | |
627 | ||
628 | nest = nla_nest_start(skb, idx++); | |
629 | if (nest == NULL) | |
630 | goto nla_put_failure; | |
631 | ||
632 | NLA_PUT_U32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id); | |
633 | NLA_PUT_STRING(skb, CTRL_ATTR_MCAST_GRP_NAME, | |
634 | grp->name); | |
635 | ||
636 | nla_nest_end(skb, nest); | |
637 | } | |
638 | nla_nest_end(skb, nla_grps); | |
639 | } | |
640 | ||
641 | return genlmsg_end(skb, hdr); | |
642 | ||
643 | nla_put_failure: | |
bc3ed28c TG |
644 | genlmsg_cancel(skb, hdr); |
645 | return -EMSGSIZE; | |
2dbba6f7 JB |
646 | } |
647 | ||
648 | static int ctrl_fill_mcgrp_info(struct genl_multicast_group *grp, u32 pid, | |
649 | u32 seq, u32 flags, struct sk_buff *skb, | |
650 | u8 cmd) | |
651 | { | |
652 | void *hdr; | |
653 | struct nlattr *nla_grps; | |
654 | struct nlattr *nest; | |
655 | ||
656 | hdr = genlmsg_put(skb, pid, seq, &genl_ctrl, flags, cmd); | |
657 | if (hdr == NULL) | |
658 | return -1; | |
659 | ||
660 | NLA_PUT_STRING(skb, CTRL_ATTR_FAMILY_NAME, grp->family->name); | |
661 | NLA_PUT_U16(skb, CTRL_ATTR_FAMILY_ID, grp->family->id); | |
662 | ||
663 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
664 | if (nla_grps == NULL) | |
665 | goto nla_put_failure; | |
666 | ||
667 | nest = nla_nest_start(skb, 1); | |
668 | if (nest == NULL) | |
669 | goto nla_put_failure; | |
670 | ||
671 | NLA_PUT_U32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id); | |
672 | NLA_PUT_STRING(skb, CTRL_ATTR_MCAST_GRP_NAME, | |
673 | grp->name); | |
674 | ||
675 | nla_nest_end(skb, nest); | |
676 | nla_nest_end(skb, nla_grps); | |
677 | ||
482a8524 TG |
678 | return genlmsg_end(skb, hdr); |
679 | ||
680 | nla_put_failure: | |
bc3ed28c TG |
681 | genlmsg_cancel(skb, hdr); |
682 | return -EMSGSIZE; | |
482a8524 TG |
683 | } |
684 | ||
685 | static int ctrl_dumpfamily(struct sk_buff *skb, struct netlink_callback *cb) | |
686 | { | |
687 | ||
688 | int i, n = 0; | |
689 | struct genl_family *rt; | |
134e6375 | 690 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
691 | int chains_to_skip = cb->args[0]; |
692 | int fams_to_skip = cb->args[1]; | |
693 | ||
694 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) { | |
695 | if (i < chains_to_skip) | |
696 | continue; | |
697 | n = 0; | |
698 | list_for_each_entry(rt, genl_family_chain(i), family_list) { | |
134e6375 JB |
699 | if (!rt->netnsok && !net_eq(net, &init_net)) |
700 | continue; | |
482a8524 TG |
701 | if (++n < fams_to_skip) |
702 | continue; | |
703 | if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).pid, | |
704 | cb->nlh->nlmsg_seq, NLM_F_MULTI, | |
705 | skb, CTRL_CMD_NEWFAMILY) < 0) | |
706 | goto errout; | |
707 | } | |
708 | ||
709 | fams_to_skip = 0; | |
710 | } | |
711 | ||
712 | errout: | |
713 | cb->args[0] = i; | |
714 | cb->args[1] = n; | |
715 | ||
716 | return skb->len; | |
717 | } | |
718 | ||
2dbba6f7 JB |
719 | static struct sk_buff *ctrl_build_family_msg(struct genl_family *family, |
720 | u32 pid, int seq, u8 cmd) | |
482a8524 TG |
721 | { |
722 | struct sk_buff *skb; | |
723 | int err; | |
724 | ||
339bf98f | 725 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); |
482a8524 TG |
726 | if (skb == NULL) |
727 | return ERR_PTR(-ENOBUFS); | |
728 | ||
729 | err = ctrl_fill_info(family, pid, seq, 0, skb, cmd); | |
730 | if (err < 0) { | |
731 | nlmsg_free(skb); | |
732 | return ERR_PTR(err); | |
733 | } | |
734 | ||
735 | return skb; | |
736 | } | |
737 | ||
2dbba6f7 JB |
738 | static struct sk_buff *ctrl_build_mcgrp_msg(struct genl_multicast_group *grp, |
739 | u32 pid, int seq, u8 cmd) | |
740 | { | |
741 | struct sk_buff *skb; | |
742 | int err; | |
743 | ||
744 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); | |
745 | if (skb == NULL) | |
746 | return ERR_PTR(-ENOBUFS); | |
747 | ||
748 | err = ctrl_fill_mcgrp_info(grp, pid, seq, 0, skb, cmd); | |
749 | if (err < 0) { | |
750 | nlmsg_free(skb); | |
751 | return ERR_PTR(err); | |
752 | } | |
753 | ||
754 | return skb; | |
755 | } | |
756 | ||
ef7c79ed | 757 | static const struct nla_policy ctrl_policy[CTRL_ATTR_MAX+1] = { |
482a8524 | 758 | [CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 }, |
5176f91e TG |
759 | [CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING, |
760 | .len = GENL_NAMSIZ - 1 }, | |
482a8524 TG |
761 | }; |
762 | ||
763 | static int ctrl_getfamily(struct sk_buff *skb, struct genl_info *info) | |
764 | { | |
765 | struct sk_buff *msg; | |
766 | struct genl_family *res = NULL; | |
767 | int err = -EINVAL; | |
768 | ||
769 | if (info->attrs[CTRL_ATTR_FAMILY_ID]) { | |
770 | u16 id = nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]); | |
771 | res = genl_family_find_byid(id); | |
134e6375 | 772 | err = -ENOENT; |
482a8524 TG |
773 | } |
774 | ||
775 | if (info->attrs[CTRL_ATTR_FAMILY_NAME]) { | |
5176f91e | 776 | char *name; |
482a8524 | 777 | |
5176f91e | 778 | name = nla_data(info->attrs[CTRL_ATTR_FAMILY_NAME]); |
482a8524 | 779 | res = genl_family_find_byname(name); |
134e6375 | 780 | err = -ENOENT; |
482a8524 TG |
781 | } |
782 | ||
134e6375 JB |
783 | if (res == NULL) |
784 | return err; | |
785 | ||
786 | if (!res->netnsok && !net_eq(genl_info_net(info), &init_net)) { | |
787 | /* family doesn't exist here */ | |
788 | return -ENOENT; | |
482a8524 TG |
789 | } |
790 | ||
2dbba6f7 JB |
791 | msg = ctrl_build_family_msg(res, info->snd_pid, info->snd_seq, |
792 | CTRL_CMD_NEWFAMILY); | |
134e6375 JB |
793 | if (IS_ERR(msg)) |
794 | return PTR_ERR(msg); | |
482a8524 | 795 | |
134e6375 | 796 | return genlmsg_reply(msg, info); |
482a8524 TG |
797 | } |
798 | ||
799 | static int genl_ctrl_event(int event, void *data) | |
800 | { | |
801 | struct sk_buff *msg; | |
134e6375 JB |
802 | struct genl_family *family; |
803 | struct genl_multicast_group *grp; | |
482a8524 | 804 | |
134e6375 JB |
805 | /* genl is still initialising */ |
806 | if (!init_net.genl_sock) | |
482a8524 TG |
807 | return 0; |
808 | ||
809 | switch (event) { | |
810 | case CTRL_CMD_NEWFAMILY: | |
811 | case CTRL_CMD_DELFAMILY: | |
134e6375 JB |
812 | family = data; |
813 | msg = ctrl_build_family_msg(family, 0, 0, event); | |
2dbba6f7 JB |
814 | break; |
815 | case CTRL_CMD_NEWMCAST_GRP: | |
816 | case CTRL_CMD_DELMCAST_GRP: | |
134e6375 JB |
817 | grp = data; |
818 | family = grp->family; | |
2dbba6f7 | 819 | msg = ctrl_build_mcgrp_msg(data, 0, 0, event); |
482a8524 | 820 | break; |
134e6375 JB |
821 | default: |
822 | return -EINVAL; | |
823 | } | |
824 | ||
825 | if (IS_ERR(msg)) | |
826 | return PTR_ERR(msg); | |
827 | ||
828 | if (!family->netnsok) { | |
829 | genlmsg_multicast_netns(&init_net, msg, 0, | |
830 | GENL_ID_CTRL, GFP_KERNEL); | |
831 | } else { | |
832 | rcu_read_lock(); | |
833 | genlmsg_multicast_allns(msg, 0, GENL_ID_CTRL, GFP_ATOMIC); | |
834 | rcu_read_unlock(); | |
482a8524 TG |
835 | } |
836 | ||
837 | return 0; | |
838 | } | |
839 | ||
840 | static struct genl_ops genl_ctrl_ops = { | |
841 | .cmd = CTRL_CMD_GETFAMILY, | |
842 | .doit = ctrl_getfamily, | |
843 | .dumpit = ctrl_dumpfamily, | |
844 | .policy = ctrl_policy, | |
845 | }; | |
846 | ||
2dbba6f7 JB |
847 | static struct genl_multicast_group notify_grp = { |
848 | .name = "notify", | |
849 | }; | |
850 | ||
134e6375 JB |
851 | static int __net_init genl_pernet_init(struct net *net) |
852 | { | |
853 | /* we'll bump the group number right afterwards */ | |
854 | net->genl_sock = netlink_kernel_create(net, NETLINK_GENERIC, 0, | |
855 | genl_rcv, &genl_mutex, | |
856 | THIS_MODULE); | |
857 | ||
858 | if (!net->genl_sock && net_eq(net, &init_net)) | |
859 | panic("GENL: Cannot initialize generic netlink\n"); | |
860 | ||
861 | if (!net->genl_sock) | |
862 | return -ENOMEM; | |
863 | ||
864 | return 0; | |
865 | } | |
866 | ||
867 | static void __net_exit genl_pernet_exit(struct net *net) | |
868 | { | |
869 | netlink_kernel_release(net->genl_sock); | |
870 | net->genl_sock = NULL; | |
871 | } | |
872 | ||
873 | static struct pernet_operations genl_pernet_ops = { | |
874 | .init = genl_pernet_init, | |
875 | .exit = genl_pernet_exit, | |
876 | }; | |
877 | ||
482a8524 TG |
878 | static int __init genl_init(void) |
879 | { | |
880 | int i, err; | |
881 | ||
882 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) | |
883 | INIT_LIST_HEAD(&family_ht[i]); | |
884 | ||
885 | err = genl_register_family(&genl_ctrl); | |
886 | if (err < 0) | |
134e6375 | 887 | goto problem; |
482a8524 TG |
888 | |
889 | err = genl_register_ops(&genl_ctrl, &genl_ctrl_ops); | |
890 | if (err < 0) | |
134e6375 | 891 | goto problem; |
482a8524 TG |
892 | |
893 | netlink_set_nonroot(NETLINK_GENERIC, NL_NONROOT_RECV); | |
2dbba6f7 | 894 | |
134e6375 JB |
895 | err = register_pernet_subsys(&genl_pernet_ops); |
896 | if (err) | |
897 | goto problem; | |
482a8524 | 898 | |
2dbba6f7 JB |
899 | err = genl_register_mc_group(&genl_ctrl, ¬ify_grp); |
900 | if (err < 0) | |
134e6375 | 901 | goto problem; |
2dbba6f7 | 902 | |
482a8524 TG |
903 | return 0; |
904 | ||
134e6375 | 905 | problem: |
482a8524 | 906 | panic("GENL: Cannot register controller: %d\n", err); |
482a8524 TG |
907 | } |
908 | ||
909 | subsys_initcall(genl_init); | |
910 | ||
482a8524 TG |
911 | EXPORT_SYMBOL(genl_register_ops); |
912 | EXPORT_SYMBOL(genl_unregister_ops); | |
913 | EXPORT_SYMBOL(genl_register_family); | |
914 | EXPORT_SYMBOL(genl_unregister_family); | |
134e6375 JB |
915 | |
916 | static int genlmsg_mcast(struct sk_buff *skb, u32 pid, unsigned long group, | |
917 | gfp_t flags) | |
918 | { | |
919 | struct sk_buff *tmp; | |
920 | struct net *net, *prev = NULL; | |
921 | int err; | |
922 | ||
923 | for_each_net_rcu(net) { | |
924 | if (prev) { | |
925 | tmp = skb_clone(skb, flags); | |
926 | if (!tmp) { | |
927 | err = -ENOMEM; | |
928 | goto error; | |
929 | } | |
930 | err = nlmsg_multicast(prev->genl_sock, tmp, | |
931 | pid, group, flags); | |
932 | if (err) | |
933 | goto error; | |
934 | } | |
935 | ||
936 | prev = net; | |
937 | } | |
938 | ||
939 | return nlmsg_multicast(prev->genl_sock, skb, pid, group, flags); | |
940 | error: | |
941 | kfree_skb(skb); | |
942 | return err; | |
943 | } | |
944 | ||
945 | int genlmsg_multicast_allns(struct sk_buff *skb, u32 pid, unsigned int group, | |
946 | gfp_t flags) | |
947 | { | |
948 | return genlmsg_mcast(skb, pid, group, flags); | |
949 | } | |
950 | EXPORT_SYMBOL(genlmsg_multicast_allns); |