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