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Commit | Line | Data |
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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> | |
5a0e3ad6 | 11 | #include <linux/slab.h> |
482a8524 TG |
12 | #include <linux/errno.h> |
13 | #include <linux/types.h> | |
14 | #include <linux/socket.h> | |
15 | #include <linux/string.h> | |
16 | #include <linux/skbuff.h> | |
14cc3e2b | 17 | #include <linux/mutex.h> |
2dbba6f7 | 18 | #include <linux/bitmap.h> |
482a8524 TG |
19 | #include <net/sock.h> |
20 | #include <net/genetlink.h> | |
21 | ||
14cc3e2b | 22 | static DEFINE_MUTEX(genl_mutex); /* serialization of message processing */ |
482a8524 | 23 | |
3b71535f | 24 | static inline void genl_lock(void) |
482a8524 | 25 | { |
14cc3e2b | 26 | mutex_lock(&genl_mutex); |
482a8524 TG |
27 | } |
28 | ||
3b71535f | 29 | static inline void genl_unlock(void) |
482a8524 | 30 | { |
14cc3e2b | 31 | mutex_unlock(&genl_mutex); |
482a8524 TG |
32 | } |
33 | ||
34 | #define GENL_FAM_TAB_SIZE 16 | |
35 | #define GENL_FAM_TAB_MASK (GENL_FAM_TAB_SIZE - 1) | |
36 | ||
37 | static struct list_head family_ht[GENL_FAM_TAB_SIZE]; | |
2dbba6f7 JB |
38 | /* |
39 | * Bitmap of multicast groups that are currently in use. | |
40 | * | |
41 | * To avoid an allocation at boot of just one unsigned long, | |
42 | * declare it global instead. | |
43 | * Bit 0 is marked as already used since group 0 is invalid. | |
44 | */ | |
45 | static unsigned long mc_group_start = 0x1; | |
46 | static unsigned long *mc_groups = &mc_group_start; | |
47 | static unsigned long mc_groups_longs = 1; | |
482a8524 TG |
48 | |
49 | static int genl_ctrl_event(int event, void *data); | |
50 | ||
51 | static inline unsigned int genl_family_hash(unsigned int id) | |
52 | { | |
53 | return id & GENL_FAM_TAB_MASK; | |
54 | } | |
55 | ||
56 | static inline struct list_head *genl_family_chain(unsigned int id) | |
57 | { | |
58 | return &family_ht[genl_family_hash(id)]; | |
59 | } | |
60 | ||
61 | static struct genl_family *genl_family_find_byid(unsigned int id) | |
62 | { | |
63 | struct genl_family *f; | |
64 | ||
65 | list_for_each_entry(f, genl_family_chain(id), family_list) | |
66 | if (f->id == id) | |
67 | return f; | |
68 | ||
69 | return NULL; | |
70 | } | |
71 | ||
72 | static struct genl_family *genl_family_find_byname(char *name) | |
73 | { | |
74 | struct genl_family *f; | |
75 | int i; | |
76 | ||
77 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) | |
78 | list_for_each_entry(f, genl_family_chain(i), family_list) | |
79 | if (strcmp(f->name, name) == 0) | |
80 | return f; | |
81 | ||
82 | return NULL; | |
83 | } | |
84 | ||
85 | static struct genl_ops *genl_get_cmd(u8 cmd, struct genl_family *family) | |
86 | { | |
87 | struct genl_ops *ops; | |
88 | ||
89 | list_for_each_entry(ops, &family->ops_list, ops_list) | |
90 | if (ops->cmd == cmd) | |
91 | return ops; | |
92 | ||
93 | return NULL; | |
94 | } | |
95 | ||
96 | /* Of course we are going to have problems once we hit | |
97 | * 2^16 alive types, but that can only happen by year 2K | |
98 | */ | |
99 | static inline u16 genl_generate_id(void) | |
100 | { | |
988ade6b KK |
101 | static u16 id_gen_idx = GENL_MIN_ID; |
102 | int i; | |
482a8524 | 103 | |
988ade6b KK |
104 | for (i = 0; i <= GENL_MAX_ID - GENL_MIN_ID; i++) { |
105 | if (!genl_family_find_byid(id_gen_idx)) | |
106 | return id_gen_idx; | |
107 | if (++id_gen_idx > GENL_MAX_ID) | |
482a8524 | 108 | id_gen_idx = GENL_MIN_ID; |
988ade6b | 109 | } |
482a8524 | 110 | |
988ade6b | 111 | return 0; |
482a8524 TG |
112 | } |
113 | ||
2dbba6f7 JB |
114 | static struct genl_multicast_group notify_grp; |
115 | ||
116 | /** | |
117 | * genl_register_mc_group - register a multicast group | |
118 | * | |
119 | * Registers the specified multicast group and notifies userspace | |
120 | * about the new group. | |
121 | * | |
122 | * Returns 0 on success or a negative error code. | |
123 | * | |
124 | * @family: The generic netlink family the group shall be registered for. | |
125 | * @grp: The group to register, must have a name. | |
126 | */ | |
127 | int genl_register_mc_group(struct genl_family *family, | |
128 | struct genl_multicast_group *grp) | |
129 | { | |
130 | int id; | |
131 | unsigned long *new_groups; | |
b1f57195 | 132 | int err = 0; |
2dbba6f7 JB |
133 | |
134 | BUG_ON(grp->name[0] == '\0'); | |
135 | ||
136 | genl_lock(); | |
137 | ||
138 | /* special-case our own group */ | |
139 | if (grp == ¬ify_grp) | |
140 | id = GENL_ID_CTRL; | |
141 | else | |
142 | id = find_first_zero_bit(mc_groups, | |
143 | mc_groups_longs * BITS_PER_LONG); | |
144 | ||
145 | ||
146 | if (id >= mc_groups_longs * BITS_PER_LONG) { | |
147 | size_t nlen = (mc_groups_longs + 1) * sizeof(unsigned long); | |
148 | ||
149 | if (mc_groups == &mc_group_start) { | |
150 | new_groups = kzalloc(nlen, GFP_KERNEL); | |
151 | if (!new_groups) { | |
152 | err = -ENOMEM; | |
153 | goto out; | |
154 | } | |
155 | mc_groups = new_groups; | |
156 | *mc_groups = mc_group_start; | |
157 | } else { | |
158 | new_groups = krealloc(mc_groups, nlen, GFP_KERNEL); | |
159 | if (!new_groups) { | |
160 | err = -ENOMEM; | |
161 | goto out; | |
162 | } | |
163 | mc_groups = new_groups; | |
164 | mc_groups[mc_groups_longs] = 0; | |
165 | } | |
166 | mc_groups_longs++; | |
167 | } | |
168 | ||
134e6375 JB |
169 | if (family->netnsok) { |
170 | struct net *net; | |
171 | ||
d136f1bd | 172 | netlink_table_grab(); |
134e6375 JB |
173 | rcu_read_lock(); |
174 | for_each_net_rcu(net) { | |
d136f1bd | 175 | err = __netlink_change_ngroups(net->genl_sock, |
134e6375 JB |
176 | mc_groups_longs * BITS_PER_LONG); |
177 | if (err) { | |
178 | /* | |
179 | * No need to roll back, can only fail if | |
180 | * memory allocation fails and then the | |
181 | * number of _possible_ groups has been | |
182 | * increased on some sockets which is ok. | |
183 | */ | |
184 | rcu_read_unlock(); | |
d136f1bd | 185 | netlink_table_ungrab(); |
134e6375 JB |
186 | goto out; |
187 | } | |
188 | } | |
189 | rcu_read_unlock(); | |
d136f1bd | 190 | netlink_table_ungrab(); |
134e6375 JB |
191 | } else { |
192 | err = netlink_change_ngroups(init_net.genl_sock, | |
193 | mc_groups_longs * BITS_PER_LONG); | |
194 | if (err) | |
195 | goto out; | |
196 | } | |
2dbba6f7 JB |
197 | |
198 | grp->id = id; | |
199 | set_bit(id, mc_groups); | |
200 | list_add_tail(&grp->list, &family->mcast_groups); | |
201 | grp->family = family; | |
202 | ||
203 | genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, grp); | |
204 | out: | |
205 | genl_unlock(); | |
79d310d0 | 206 | return err; |
2dbba6f7 JB |
207 | } |
208 | EXPORT_SYMBOL(genl_register_mc_group); | |
209 | ||
79dc4386 TG |
210 | static void __genl_unregister_mc_group(struct genl_family *family, |
211 | struct genl_multicast_group *grp) | |
212 | { | |
134e6375 | 213 | struct net *net; |
79dc4386 | 214 | BUG_ON(grp->family != family); |
134e6375 | 215 | |
b8273570 | 216 | netlink_table_grab(); |
134e6375 JB |
217 | rcu_read_lock(); |
218 | for_each_net_rcu(net) | |
b8273570 | 219 | __netlink_clear_multicast_users(net->genl_sock, grp->id); |
134e6375 | 220 | rcu_read_unlock(); |
b8273570 | 221 | netlink_table_ungrab(); |
134e6375 | 222 | |
79dc4386 TG |
223 | clear_bit(grp->id, mc_groups); |
224 | list_del(&grp->list); | |
225 | genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, grp); | |
226 | grp->id = 0; | |
227 | grp->family = NULL; | |
228 | } | |
229 | ||
2dbba6f7 JB |
230 | /** |
231 | * genl_unregister_mc_group - unregister a multicast group | |
232 | * | |
233 | * Unregisters the specified multicast group and notifies userspace | |
234 | * about it. All current listeners on the group are removed. | |
235 | * | |
236 | * Note: It is not necessary to unregister all multicast groups before | |
237 | * unregistering the family, unregistering the family will cause | |
238 | * all assigned multicast groups to be unregistered automatically. | |
239 | * | |
240 | * @family: Generic netlink family the group belongs to. | |
241 | * @grp: The group to unregister, must have been registered successfully | |
242 | * previously. | |
243 | */ | |
244 | void genl_unregister_mc_group(struct genl_family *family, | |
245 | struct genl_multicast_group *grp) | |
246 | { | |
2dbba6f7 | 247 | genl_lock(); |
79dc4386 | 248 | __genl_unregister_mc_group(family, grp); |
2dbba6f7 JB |
249 | genl_unlock(); |
250 | } | |
3efb40c2 | 251 | EXPORT_SYMBOL(genl_unregister_mc_group); |
2dbba6f7 JB |
252 | |
253 | static void genl_unregister_mc_groups(struct genl_family *family) | |
254 | { | |
255 | struct genl_multicast_group *grp, *tmp; | |
256 | ||
257 | list_for_each_entry_safe(grp, tmp, &family->mcast_groups, list) | |
79dc4386 | 258 | __genl_unregister_mc_group(family, grp); |
2dbba6f7 JB |
259 | } |
260 | ||
482a8524 TG |
261 | /** |
262 | * genl_register_ops - register generic netlink operations | |
263 | * @family: generic netlink family | |
264 | * @ops: operations to be registered | |
265 | * | |
266 | * Registers the specified operations and assigns them to the specified | |
267 | * family. Either a doit or dumpit callback must be specified or the | |
268 | * operation will fail. Only one operation structure per command | |
269 | * identifier may be registered. | |
270 | * | |
271 | * See include/net/genetlink.h for more documenation on the operations | |
272 | * structure. | |
273 | * | |
274 | * Returns 0 on success or a negative error code. | |
275 | */ | |
276 | int genl_register_ops(struct genl_family *family, struct genl_ops *ops) | |
277 | { | |
278 | int err = -EINVAL; | |
279 | ||
280 | if (ops->dumpit == NULL && ops->doit == NULL) | |
281 | goto errout; | |
282 | ||
283 | if (genl_get_cmd(ops->cmd, family)) { | |
284 | err = -EEXIST; | |
285 | goto errout; | |
286 | } | |
287 | ||
334c29a6 | 288 | if (ops->dumpit) |
334c29a6 | 289 | ops->flags |= GENL_CMD_CAP_DUMP; |
48d4ed7a JHS |
290 | if (ops->doit) |
291 | ops->flags |= GENL_CMD_CAP_DO; | |
334c29a6 JHS |
292 | if (ops->policy) |
293 | ops->flags |= GENL_CMD_CAP_HASPOL; | |
294 | ||
482a8524 TG |
295 | genl_lock(); |
296 | list_add_tail(&ops->ops_list, &family->ops_list); | |
297 | genl_unlock(); | |
298 | ||
299 | genl_ctrl_event(CTRL_CMD_NEWOPS, ops); | |
300 | err = 0; | |
301 | errout: | |
302 | return err; | |
303 | } | |
304 | ||
305 | /** | |
306 | * genl_unregister_ops - unregister generic netlink operations | |
307 | * @family: generic netlink family | |
308 | * @ops: operations to be unregistered | |
309 | * | |
310 | * Unregisters the specified operations and unassigns them from the | |
311 | * specified family. The operation blocks until the current message | |
312 | * processing has finished and doesn't start again until the | |
313 | * unregister process has finished. | |
314 | * | |
315 | * Note: It is not necessary to unregister all operations before | |
316 | * unregistering the family, unregistering the family will cause | |
317 | * all assigned operations to be unregistered automatically. | |
318 | * | |
319 | * Returns 0 on success or a negative error code. | |
320 | */ | |
321 | int genl_unregister_ops(struct genl_family *family, struct genl_ops *ops) | |
322 | { | |
323 | struct genl_ops *rc; | |
324 | ||
325 | genl_lock(); | |
326 | list_for_each_entry(rc, &family->ops_list, ops_list) { | |
327 | if (rc == ops) { | |
328 | list_del(&ops->ops_list); | |
329 | genl_unlock(); | |
330 | genl_ctrl_event(CTRL_CMD_DELOPS, ops); | |
331 | return 0; | |
332 | } | |
333 | } | |
334 | genl_unlock(); | |
335 | ||
336 | return -ENOENT; | |
337 | } | |
338 | ||
339 | /** | |
340 | * genl_register_family - register a generic netlink family | |
341 | * @family: generic netlink family | |
342 | * | |
343 | * Registers the specified family after validating it first. Only one | |
344 | * family may be registered with the same family name or identifier. | |
345 | * The family id may equal GENL_ID_GENERATE causing an unique id to | |
346 | * be automatically generated and assigned. | |
347 | * | |
348 | * Return 0 on success or a negative error code. | |
349 | */ | |
350 | int genl_register_family(struct genl_family *family) | |
351 | { | |
352 | int err = -EINVAL; | |
353 | ||
354 | if (family->id && family->id < GENL_MIN_ID) | |
355 | goto errout; | |
356 | ||
357 | if (family->id > GENL_MAX_ID) | |
358 | goto errout; | |
359 | ||
360 | INIT_LIST_HEAD(&family->ops_list); | |
2dbba6f7 | 361 | INIT_LIST_HEAD(&family->mcast_groups); |
482a8524 TG |
362 | |
363 | genl_lock(); | |
364 | ||
365 | if (genl_family_find_byname(family->name)) { | |
366 | err = -EEXIST; | |
367 | goto errout_locked; | |
368 | } | |
369 | ||
482a8524 TG |
370 | if (family->id == GENL_ID_GENERATE) { |
371 | u16 newid = genl_generate_id(); | |
372 | ||
373 | if (!newid) { | |
374 | err = -ENOMEM; | |
375 | goto errout_locked; | |
376 | } | |
377 | ||
378 | family->id = newid; | |
93860b08 KK |
379 | } else if (genl_family_find_byid(family->id)) { |
380 | err = -EEXIST; | |
381 | goto errout_locked; | |
482a8524 TG |
382 | } |
383 | ||
384 | if (family->maxattr) { | |
385 | family->attrbuf = kmalloc((family->maxattr+1) * | |
386 | sizeof(struct nlattr *), GFP_KERNEL); | |
387 | if (family->attrbuf == NULL) { | |
388 | err = -ENOMEM; | |
e200bd80 | 389 | goto errout_locked; |
482a8524 TG |
390 | } |
391 | } else | |
392 | family->attrbuf = NULL; | |
393 | ||
394 | list_add_tail(&family->family_list, genl_family_chain(family->id)); | |
395 | genl_unlock(); | |
396 | ||
397 | genl_ctrl_event(CTRL_CMD_NEWFAMILY, family); | |
398 | ||
399 | return 0; | |
400 | ||
401 | errout_locked: | |
402 | genl_unlock(); | |
403 | errout: | |
404 | return err; | |
405 | } | |
406 | ||
a7b11d73 MM |
407 | /** |
408 | * genl_register_family_with_ops - register a generic netlink family | |
409 | * @family: generic netlink family | |
410 | * @ops: operations to be registered | |
411 | * @n_ops: number of elements to register | |
412 | * | |
413 | * Registers the specified family and operations from the specified table. | |
414 | * Only one family may be registered with the same family name or identifier. | |
415 | * | |
416 | * The family id may equal GENL_ID_GENERATE causing an unique id to | |
417 | * be automatically generated and assigned. | |
418 | * | |
419 | * Either a doit or dumpit callback must be specified for every registered | |
420 | * operation or the function will fail. Only one operation structure per | |
421 | * command identifier may be registered. | |
422 | * | |
423 | * See include/net/genetlink.h for more documenation on the operations | |
424 | * structure. | |
425 | * | |
426 | * This is equivalent to calling genl_register_family() followed by | |
427 | * genl_register_ops() for every operation entry in the table taking | |
428 | * care to unregister the family on error path. | |
429 | * | |
430 | * Return 0 on success or a negative error code. | |
431 | */ | |
432 | int genl_register_family_with_ops(struct genl_family *family, | |
433 | struct genl_ops *ops, size_t n_ops) | |
434 | { | |
435 | int err, i; | |
436 | ||
437 | err = genl_register_family(family); | |
438 | if (err) | |
439 | return err; | |
440 | ||
441 | for (i = 0; i < n_ops; ++i, ++ops) { | |
442 | err = genl_register_ops(family, ops); | |
443 | if (err) | |
444 | goto err_out; | |
445 | } | |
446 | return 0; | |
447 | err_out: | |
448 | genl_unregister_family(family); | |
449 | return err; | |
450 | } | |
451 | EXPORT_SYMBOL(genl_register_family_with_ops); | |
452 | ||
482a8524 TG |
453 | /** |
454 | * genl_unregister_family - unregister generic netlink family | |
455 | * @family: generic netlink family | |
456 | * | |
457 | * Unregisters the specified family. | |
458 | * | |
459 | * Returns 0 on success or a negative error code. | |
460 | */ | |
461 | int genl_unregister_family(struct genl_family *family) | |
462 | { | |
463 | struct genl_family *rc; | |
464 | ||
465 | genl_lock(); | |
466 | ||
910d6c32 PE |
467 | genl_unregister_mc_groups(family); |
468 | ||
482a8524 TG |
469 | list_for_each_entry(rc, genl_family_chain(family->id), family_list) { |
470 | if (family->id != rc->id || strcmp(rc->name, family->name)) | |
471 | continue; | |
472 | ||
473 | list_del(&rc->family_list); | |
474 | INIT_LIST_HEAD(&family->ops_list); | |
475 | genl_unlock(); | |
476 | ||
482a8524 TG |
477 | kfree(family->attrbuf); |
478 | genl_ctrl_event(CTRL_CMD_DELFAMILY, family); | |
479 | return 0; | |
480 | } | |
481 | ||
482 | genl_unlock(); | |
483 | ||
484 | return -ENOENT; | |
485 | } | |
486 | ||
1d00a4eb | 487 | static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) |
482a8524 TG |
488 | { |
489 | struct genl_ops *ops; | |
490 | struct genl_family *family; | |
134e6375 | 491 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
492 | struct genl_info info; |
493 | struct genlmsghdr *hdr = nlmsg_data(nlh); | |
1d00a4eb | 494 | int hdrlen, err; |
482a8524 | 495 | |
746fac4d | 496 | family = genl_family_find_byid(nlh->nlmsg_type); |
1d00a4eb TG |
497 | if (family == NULL) |
498 | return -ENOENT; | |
482a8524 | 499 | |
134e6375 JB |
500 | /* this family doesn't exist in this netns */ |
501 | if (!family->netnsok && !net_eq(net, &init_net)) | |
502 | return -ENOENT; | |
503 | ||
482a8524 TG |
504 | hdrlen = GENL_HDRLEN + family->hdrsize; |
505 | if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) | |
1d00a4eb | 506 | return -EINVAL; |
482a8524 TG |
507 | |
508 | ops = genl_get_cmd(hdr->cmd, family); | |
1d00a4eb TG |
509 | if (ops == NULL) |
510 | return -EOPNOTSUPP; | |
482a8524 | 511 | |
1d00a4eb TG |
512 | if ((ops->flags & GENL_ADMIN_PERM) && |
513 | security_netlink_recv(skb, CAP_NET_ADMIN)) | |
514 | return -EPERM; | |
482a8524 TG |
515 | |
516 | if (nlh->nlmsg_flags & NLM_F_DUMP) { | |
1d00a4eb TG |
517 | if (ops->dumpit == NULL) |
518 | return -EOPNOTSUPP; | |
482a8524 | 519 | |
6d1a3fb5 | 520 | genl_unlock(); |
134e6375 | 521 | err = netlink_dump_start(net->genl_sock, skb, nlh, |
6d1a3fb5 PM |
522 | ops->dumpit, ops->done); |
523 | genl_lock(); | |
524 | return err; | |
482a8524 TG |
525 | } |
526 | ||
1d00a4eb TG |
527 | if (ops->doit == NULL) |
528 | return -EOPNOTSUPP; | |
482a8524 TG |
529 | |
530 | if (family->attrbuf) { | |
531 | err = nlmsg_parse(nlh, hdrlen, family->attrbuf, family->maxattr, | |
532 | ops->policy); | |
533 | if (err < 0) | |
1d00a4eb | 534 | return err; |
482a8524 TG |
535 | } |
536 | ||
537 | info.snd_seq = nlh->nlmsg_seq; | |
538 | info.snd_pid = NETLINK_CB(skb).pid; | |
539 | info.nlhdr = nlh; | |
540 | info.genlhdr = nlmsg_data(nlh); | |
541 | info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN; | |
542 | info.attrs = family->attrbuf; | |
134e6375 | 543 | genl_info_net_set(&info, net); |
482a8524 | 544 | |
1d00a4eb | 545 | return ops->doit(skb, &info); |
482a8524 TG |
546 | } |
547 | ||
cd40b7d3 | 548 | static void genl_rcv(struct sk_buff *skb) |
482a8524 | 549 | { |
cd40b7d3 DL |
550 | genl_lock(); |
551 | netlink_rcv_skb(skb, &genl_rcv_msg); | |
552 | genl_unlock(); | |
482a8524 TG |
553 | } |
554 | ||
555 | /************************************************************************** | |
556 | * Controller | |
557 | **************************************************************************/ | |
558 | ||
17c157c8 TG |
559 | static struct genl_family genl_ctrl = { |
560 | .id = GENL_ID_CTRL, | |
561 | .name = "nlctrl", | |
334c29a6 | 562 | .version = 0x2, |
17c157c8 | 563 | .maxattr = CTRL_ATTR_MAX, |
134e6375 | 564 | .netnsok = true, |
17c157c8 TG |
565 | }; |
566 | ||
482a8524 TG |
567 | static int ctrl_fill_info(struct genl_family *family, u32 pid, u32 seq, |
568 | u32 flags, struct sk_buff *skb, u8 cmd) | |
569 | { | |
570 | void *hdr; | |
571 | ||
17c157c8 | 572 | hdr = genlmsg_put(skb, pid, seq, &genl_ctrl, flags, cmd); |
482a8524 TG |
573 | if (hdr == NULL) |
574 | return -1; | |
575 | ||
576 | NLA_PUT_STRING(skb, CTRL_ATTR_FAMILY_NAME, family->name); | |
577 | NLA_PUT_U16(skb, CTRL_ATTR_FAMILY_ID, family->id); | |
eb328111 TG |
578 | NLA_PUT_U32(skb, CTRL_ATTR_VERSION, family->version); |
579 | NLA_PUT_U32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize); | |
580 | NLA_PUT_U32(skb, CTRL_ATTR_MAXATTR, family->maxattr); | |
581 | ||
e94ef682 TG |
582 | if (!list_empty(&family->ops_list)) { |
583 | struct nlattr *nla_ops; | |
584 | struct genl_ops *ops; | |
585 | int idx = 1; | |
eb328111 | 586 | |
e94ef682 TG |
587 | nla_ops = nla_nest_start(skb, CTRL_ATTR_OPS); |
588 | if (nla_ops == NULL) | |
eb328111 TG |
589 | goto nla_put_failure; |
590 | ||
e94ef682 TG |
591 | list_for_each_entry(ops, &family->ops_list, ops_list) { |
592 | struct nlattr *nest; | |
eb328111 | 593 | |
e94ef682 TG |
594 | nest = nla_nest_start(skb, idx++); |
595 | if (nest == NULL) | |
596 | goto nla_put_failure; | |
eb328111 | 597 | |
e94ef682 TG |
598 | NLA_PUT_U32(skb, CTRL_ATTR_OP_ID, ops->cmd); |
599 | NLA_PUT_U32(skb, CTRL_ATTR_OP_FLAGS, ops->flags); | |
eb328111 | 600 | |
e94ef682 TG |
601 | nla_nest_end(skb, nest); |
602 | } | |
603 | ||
604 | nla_nest_end(skb, nla_ops); | |
605 | } | |
482a8524 | 606 | |
2dbba6f7 JB |
607 | if (!list_empty(&family->mcast_groups)) { |
608 | struct genl_multicast_group *grp; | |
609 | struct nlattr *nla_grps; | |
610 | int idx = 1; | |
611 | ||
612 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
613 | if (nla_grps == NULL) | |
614 | goto nla_put_failure; | |
615 | ||
616 | list_for_each_entry(grp, &family->mcast_groups, list) { | |
617 | struct nlattr *nest; | |
618 | ||
619 | nest = nla_nest_start(skb, idx++); | |
620 | if (nest == NULL) | |
621 | goto nla_put_failure; | |
622 | ||
623 | NLA_PUT_U32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id); | |
624 | NLA_PUT_STRING(skb, CTRL_ATTR_MCAST_GRP_NAME, | |
625 | grp->name); | |
626 | ||
627 | nla_nest_end(skb, nest); | |
628 | } | |
629 | nla_nest_end(skb, nla_grps); | |
630 | } | |
631 | ||
632 | return genlmsg_end(skb, hdr); | |
633 | ||
634 | nla_put_failure: | |
bc3ed28c TG |
635 | genlmsg_cancel(skb, hdr); |
636 | return -EMSGSIZE; | |
2dbba6f7 JB |
637 | } |
638 | ||
639 | static int ctrl_fill_mcgrp_info(struct genl_multicast_group *grp, u32 pid, | |
640 | u32 seq, u32 flags, struct sk_buff *skb, | |
641 | u8 cmd) | |
642 | { | |
643 | void *hdr; | |
644 | struct nlattr *nla_grps; | |
645 | struct nlattr *nest; | |
646 | ||
647 | hdr = genlmsg_put(skb, pid, seq, &genl_ctrl, flags, cmd); | |
648 | if (hdr == NULL) | |
649 | return -1; | |
650 | ||
651 | NLA_PUT_STRING(skb, CTRL_ATTR_FAMILY_NAME, grp->family->name); | |
652 | NLA_PUT_U16(skb, CTRL_ATTR_FAMILY_ID, grp->family->id); | |
653 | ||
654 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
655 | if (nla_grps == NULL) | |
656 | goto nla_put_failure; | |
657 | ||
658 | nest = nla_nest_start(skb, 1); | |
659 | if (nest == NULL) | |
660 | goto nla_put_failure; | |
661 | ||
662 | NLA_PUT_U32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id); | |
663 | NLA_PUT_STRING(skb, CTRL_ATTR_MCAST_GRP_NAME, | |
664 | grp->name); | |
665 | ||
666 | nla_nest_end(skb, nest); | |
667 | nla_nest_end(skb, nla_grps); | |
668 | ||
482a8524 TG |
669 | return genlmsg_end(skb, hdr); |
670 | ||
671 | nla_put_failure: | |
bc3ed28c TG |
672 | genlmsg_cancel(skb, hdr); |
673 | return -EMSGSIZE; | |
482a8524 TG |
674 | } |
675 | ||
676 | static int ctrl_dumpfamily(struct sk_buff *skb, struct netlink_callback *cb) | |
677 | { | |
678 | ||
679 | int i, n = 0; | |
680 | struct genl_family *rt; | |
134e6375 | 681 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
682 | int chains_to_skip = cb->args[0]; |
683 | int fams_to_skip = cb->args[1]; | |
684 | ||
e1d5a010 | 685 | for (i = chains_to_skip; i < GENL_FAM_TAB_SIZE; i++) { |
482a8524 TG |
686 | n = 0; |
687 | list_for_each_entry(rt, genl_family_chain(i), family_list) { | |
134e6375 JB |
688 | if (!rt->netnsok && !net_eq(net, &init_net)) |
689 | continue; | |
482a8524 TG |
690 | if (++n < fams_to_skip) |
691 | continue; | |
692 | if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).pid, | |
693 | cb->nlh->nlmsg_seq, NLM_F_MULTI, | |
694 | skb, CTRL_CMD_NEWFAMILY) < 0) | |
695 | goto errout; | |
696 | } | |
697 | ||
698 | fams_to_skip = 0; | |
699 | } | |
700 | ||
701 | errout: | |
702 | cb->args[0] = i; | |
703 | cb->args[1] = n; | |
704 | ||
705 | return skb->len; | |
706 | } | |
707 | ||
2dbba6f7 JB |
708 | static struct sk_buff *ctrl_build_family_msg(struct genl_family *family, |
709 | u32 pid, int seq, u8 cmd) | |
482a8524 TG |
710 | { |
711 | struct sk_buff *skb; | |
712 | int err; | |
713 | ||
339bf98f | 714 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); |
482a8524 TG |
715 | if (skb == NULL) |
716 | return ERR_PTR(-ENOBUFS); | |
717 | ||
718 | err = ctrl_fill_info(family, pid, seq, 0, skb, cmd); | |
719 | if (err < 0) { | |
720 | nlmsg_free(skb); | |
721 | return ERR_PTR(err); | |
722 | } | |
723 | ||
724 | return skb; | |
725 | } | |
726 | ||
2dbba6f7 JB |
727 | static struct sk_buff *ctrl_build_mcgrp_msg(struct genl_multicast_group *grp, |
728 | u32 pid, int seq, u8 cmd) | |
729 | { | |
730 | struct sk_buff *skb; | |
731 | int err; | |
732 | ||
733 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); | |
734 | if (skb == NULL) | |
735 | return ERR_PTR(-ENOBUFS); | |
736 | ||
737 | err = ctrl_fill_mcgrp_info(grp, pid, seq, 0, skb, cmd); | |
738 | if (err < 0) { | |
739 | nlmsg_free(skb); | |
740 | return ERR_PTR(err); | |
741 | } | |
742 | ||
743 | return skb; | |
744 | } | |
745 | ||
ef7c79ed | 746 | static const struct nla_policy ctrl_policy[CTRL_ATTR_MAX+1] = { |
482a8524 | 747 | [CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 }, |
5176f91e TG |
748 | [CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING, |
749 | .len = GENL_NAMSIZ - 1 }, | |
482a8524 TG |
750 | }; |
751 | ||
752 | static int ctrl_getfamily(struct sk_buff *skb, struct genl_info *info) | |
753 | { | |
754 | struct sk_buff *msg; | |
755 | struct genl_family *res = NULL; | |
756 | int err = -EINVAL; | |
757 | ||
758 | if (info->attrs[CTRL_ATTR_FAMILY_ID]) { | |
759 | u16 id = nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]); | |
760 | res = genl_family_find_byid(id); | |
134e6375 | 761 | err = -ENOENT; |
482a8524 TG |
762 | } |
763 | ||
764 | if (info->attrs[CTRL_ATTR_FAMILY_NAME]) { | |
5176f91e | 765 | char *name; |
482a8524 | 766 | |
5176f91e | 767 | name = nla_data(info->attrs[CTRL_ATTR_FAMILY_NAME]); |
482a8524 | 768 | res = genl_family_find_byname(name); |
134e6375 | 769 | err = -ENOENT; |
482a8524 TG |
770 | } |
771 | ||
134e6375 JB |
772 | if (res == NULL) |
773 | return err; | |
774 | ||
775 | if (!res->netnsok && !net_eq(genl_info_net(info), &init_net)) { | |
776 | /* family doesn't exist here */ | |
777 | return -ENOENT; | |
482a8524 TG |
778 | } |
779 | ||
2dbba6f7 JB |
780 | msg = ctrl_build_family_msg(res, info->snd_pid, info->snd_seq, |
781 | CTRL_CMD_NEWFAMILY); | |
134e6375 JB |
782 | if (IS_ERR(msg)) |
783 | return PTR_ERR(msg); | |
482a8524 | 784 | |
134e6375 | 785 | return genlmsg_reply(msg, info); |
482a8524 TG |
786 | } |
787 | ||
788 | static int genl_ctrl_event(int event, void *data) | |
789 | { | |
790 | struct sk_buff *msg; | |
134e6375 JB |
791 | struct genl_family *family; |
792 | struct genl_multicast_group *grp; | |
482a8524 | 793 | |
134e6375 JB |
794 | /* genl is still initialising */ |
795 | if (!init_net.genl_sock) | |
482a8524 TG |
796 | return 0; |
797 | ||
798 | switch (event) { | |
799 | case CTRL_CMD_NEWFAMILY: | |
800 | case CTRL_CMD_DELFAMILY: | |
134e6375 JB |
801 | family = data; |
802 | msg = ctrl_build_family_msg(family, 0, 0, event); | |
2dbba6f7 JB |
803 | break; |
804 | case CTRL_CMD_NEWMCAST_GRP: | |
805 | case CTRL_CMD_DELMCAST_GRP: | |
134e6375 JB |
806 | grp = data; |
807 | family = grp->family; | |
2dbba6f7 | 808 | msg = ctrl_build_mcgrp_msg(data, 0, 0, event); |
482a8524 | 809 | break; |
134e6375 JB |
810 | default: |
811 | return -EINVAL; | |
812 | } | |
813 | ||
814 | if (IS_ERR(msg)) | |
815 | return PTR_ERR(msg); | |
816 | ||
817 | if (!family->netnsok) { | |
818 | genlmsg_multicast_netns(&init_net, msg, 0, | |
819 | GENL_ID_CTRL, GFP_KERNEL); | |
820 | } else { | |
821 | rcu_read_lock(); | |
822 | genlmsg_multicast_allns(msg, 0, GENL_ID_CTRL, GFP_ATOMIC); | |
823 | rcu_read_unlock(); | |
482a8524 TG |
824 | } |
825 | ||
826 | return 0; | |
827 | } | |
828 | ||
829 | static struct genl_ops genl_ctrl_ops = { | |
830 | .cmd = CTRL_CMD_GETFAMILY, | |
831 | .doit = ctrl_getfamily, | |
832 | .dumpit = ctrl_dumpfamily, | |
833 | .policy = ctrl_policy, | |
834 | }; | |
835 | ||
2dbba6f7 JB |
836 | static struct genl_multicast_group notify_grp = { |
837 | .name = "notify", | |
838 | }; | |
839 | ||
134e6375 JB |
840 | static int __net_init genl_pernet_init(struct net *net) |
841 | { | |
842 | /* we'll bump the group number right afterwards */ | |
843 | net->genl_sock = netlink_kernel_create(net, NETLINK_GENERIC, 0, | |
844 | genl_rcv, &genl_mutex, | |
845 | THIS_MODULE); | |
846 | ||
847 | if (!net->genl_sock && net_eq(net, &init_net)) | |
848 | panic("GENL: Cannot initialize generic netlink\n"); | |
849 | ||
850 | if (!net->genl_sock) | |
851 | return -ENOMEM; | |
852 | ||
853 | return 0; | |
854 | } | |
855 | ||
856 | static void __net_exit genl_pernet_exit(struct net *net) | |
857 | { | |
858 | netlink_kernel_release(net->genl_sock); | |
859 | net->genl_sock = NULL; | |
860 | } | |
861 | ||
862 | static struct pernet_operations genl_pernet_ops = { | |
863 | .init = genl_pernet_init, | |
864 | .exit = genl_pernet_exit, | |
865 | }; | |
866 | ||
482a8524 TG |
867 | static int __init genl_init(void) |
868 | { | |
869 | int i, err; | |
870 | ||
871 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) | |
872 | INIT_LIST_HEAD(&family_ht[i]); | |
873 | ||
874 | err = genl_register_family(&genl_ctrl); | |
875 | if (err < 0) | |
134e6375 | 876 | goto problem; |
482a8524 TG |
877 | |
878 | err = genl_register_ops(&genl_ctrl, &genl_ctrl_ops); | |
879 | if (err < 0) | |
134e6375 | 880 | goto problem; |
482a8524 TG |
881 | |
882 | netlink_set_nonroot(NETLINK_GENERIC, NL_NONROOT_RECV); | |
2dbba6f7 | 883 | |
134e6375 JB |
884 | err = register_pernet_subsys(&genl_pernet_ops); |
885 | if (err) | |
886 | goto problem; | |
482a8524 | 887 | |
2dbba6f7 JB |
888 | err = genl_register_mc_group(&genl_ctrl, ¬ify_grp); |
889 | if (err < 0) | |
134e6375 | 890 | goto problem; |
2dbba6f7 | 891 | |
482a8524 TG |
892 | return 0; |
893 | ||
134e6375 | 894 | problem: |
482a8524 | 895 | panic("GENL: Cannot register controller: %d\n", err); |
482a8524 TG |
896 | } |
897 | ||
898 | subsys_initcall(genl_init); | |
899 | ||
482a8524 TG |
900 | EXPORT_SYMBOL(genl_register_ops); |
901 | EXPORT_SYMBOL(genl_unregister_ops); | |
902 | EXPORT_SYMBOL(genl_register_family); | |
903 | EXPORT_SYMBOL(genl_unregister_family); | |
134e6375 JB |
904 | |
905 | static int genlmsg_mcast(struct sk_buff *skb, u32 pid, unsigned long group, | |
906 | gfp_t flags) | |
907 | { | |
908 | struct sk_buff *tmp; | |
909 | struct net *net, *prev = NULL; | |
910 | int err; | |
911 | ||
912 | for_each_net_rcu(net) { | |
913 | if (prev) { | |
914 | tmp = skb_clone(skb, flags); | |
915 | if (!tmp) { | |
916 | err = -ENOMEM; | |
917 | goto error; | |
918 | } | |
919 | err = nlmsg_multicast(prev->genl_sock, tmp, | |
920 | pid, group, flags); | |
921 | if (err) | |
922 | goto error; | |
923 | } | |
924 | ||
925 | prev = net; | |
926 | } | |
927 | ||
928 | return nlmsg_multicast(prev->genl_sock, skb, pid, group, flags); | |
929 | error: | |
930 | kfree_skb(skb); | |
931 | return err; | |
932 | } | |
933 | ||
934 | int genlmsg_multicast_allns(struct sk_buff *skb, u32 pid, unsigned int group, | |
935 | gfp_t flags) | |
936 | { | |
937 | return genlmsg_mcast(skb, pid, group, flags); | |
938 | } | |
939 | EXPORT_SYMBOL(genlmsg_multicast_allns); |