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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 | |
f408e0ce | 24 | void genl_lock(void) |
482a8524 | 25 | { |
14cc3e2b | 26 | mutex_lock(&genl_mutex); |
482a8524 | 27 | } |
f408e0ce | 28 | EXPORT_SYMBOL(genl_lock); |
482a8524 | 29 | |
f408e0ce | 30 | void genl_unlock(void) |
482a8524 | 31 | { |
14cc3e2b | 32 | mutex_unlock(&genl_mutex); |
482a8524 | 33 | } |
f408e0ce | 34 | EXPORT_SYMBOL(genl_unlock); |
482a8524 | 35 | |
86b1309c PS |
36 | #ifdef CONFIG_PROVE_LOCKING |
37 | int lockdep_genl_is_held(void) | |
38 | { | |
39 | return lockdep_is_held(&genl_mutex); | |
40 | } | |
41 | EXPORT_SYMBOL(lockdep_genl_is_held); | |
42 | #endif | |
43 | ||
482a8524 TG |
44 | #define GENL_FAM_TAB_SIZE 16 |
45 | #define GENL_FAM_TAB_MASK (GENL_FAM_TAB_SIZE - 1) | |
46 | ||
47 | static struct list_head family_ht[GENL_FAM_TAB_SIZE]; | |
2dbba6f7 JB |
48 | /* |
49 | * Bitmap of multicast groups that are currently in use. | |
50 | * | |
51 | * To avoid an allocation at boot of just one unsigned long, | |
52 | * declare it global instead. | |
53 | * Bit 0 is marked as already used since group 0 is invalid. | |
54 | */ | |
55 | static unsigned long mc_group_start = 0x1; | |
56 | static unsigned long *mc_groups = &mc_group_start; | |
57 | static unsigned long mc_groups_longs = 1; | |
482a8524 TG |
58 | |
59 | static int genl_ctrl_event(int event, void *data); | |
60 | ||
61 | static inline unsigned int genl_family_hash(unsigned int id) | |
62 | { | |
63 | return id & GENL_FAM_TAB_MASK; | |
64 | } | |
65 | ||
66 | static inline struct list_head *genl_family_chain(unsigned int id) | |
67 | { | |
68 | return &family_ht[genl_family_hash(id)]; | |
69 | } | |
70 | ||
71 | static struct genl_family *genl_family_find_byid(unsigned int id) | |
72 | { | |
73 | struct genl_family *f; | |
74 | ||
75 | list_for_each_entry(f, genl_family_chain(id), family_list) | |
76 | if (f->id == id) | |
77 | return f; | |
78 | ||
79 | return NULL; | |
80 | } | |
81 | ||
82 | static struct genl_family *genl_family_find_byname(char *name) | |
83 | { | |
84 | struct genl_family *f; | |
85 | int i; | |
86 | ||
87 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) | |
88 | list_for_each_entry(f, genl_family_chain(i), family_list) | |
89 | if (strcmp(f->name, name) == 0) | |
90 | return f; | |
91 | ||
92 | return NULL; | |
93 | } | |
94 | ||
95 | static struct genl_ops *genl_get_cmd(u8 cmd, struct genl_family *family) | |
96 | { | |
97 | struct genl_ops *ops; | |
98 | ||
99 | list_for_each_entry(ops, &family->ops_list, ops_list) | |
100 | if (ops->cmd == cmd) | |
101 | return ops; | |
102 | ||
103 | return NULL; | |
104 | } | |
105 | ||
106 | /* Of course we are going to have problems once we hit | |
107 | * 2^16 alive types, but that can only happen by year 2K | |
108 | */ | |
b57ef81f | 109 | static u16 genl_generate_id(void) |
482a8524 | 110 | { |
988ade6b KK |
111 | static u16 id_gen_idx = GENL_MIN_ID; |
112 | int i; | |
482a8524 | 113 | |
988ade6b KK |
114 | for (i = 0; i <= GENL_MAX_ID - GENL_MIN_ID; i++) { |
115 | if (!genl_family_find_byid(id_gen_idx)) | |
116 | return id_gen_idx; | |
117 | if (++id_gen_idx > GENL_MAX_ID) | |
482a8524 | 118 | id_gen_idx = GENL_MIN_ID; |
988ade6b | 119 | } |
482a8524 | 120 | |
988ade6b | 121 | return 0; |
482a8524 TG |
122 | } |
123 | ||
2dbba6f7 JB |
124 | static struct genl_multicast_group notify_grp; |
125 | ||
126 | /** | |
127 | * genl_register_mc_group - register a multicast group | |
128 | * | |
129 | * Registers the specified multicast group and notifies userspace | |
130 | * about the new group. | |
131 | * | |
132 | * Returns 0 on success or a negative error code. | |
133 | * | |
134 | * @family: The generic netlink family the group shall be registered for. | |
135 | * @grp: The group to register, must have a name. | |
136 | */ | |
137 | int genl_register_mc_group(struct genl_family *family, | |
138 | struct genl_multicast_group *grp) | |
139 | { | |
140 | int id; | |
141 | unsigned long *new_groups; | |
b1f57195 | 142 | int err = 0; |
2dbba6f7 JB |
143 | |
144 | BUG_ON(grp->name[0] == '\0'); | |
145 | ||
146 | genl_lock(); | |
147 | ||
148 | /* special-case our own group */ | |
149 | if (grp == ¬ify_grp) | |
150 | id = GENL_ID_CTRL; | |
151 | else | |
152 | id = find_first_zero_bit(mc_groups, | |
153 | mc_groups_longs * BITS_PER_LONG); | |
154 | ||
155 | ||
156 | if (id >= mc_groups_longs * BITS_PER_LONG) { | |
157 | size_t nlen = (mc_groups_longs + 1) * sizeof(unsigned long); | |
158 | ||
159 | if (mc_groups == &mc_group_start) { | |
160 | new_groups = kzalloc(nlen, GFP_KERNEL); | |
161 | if (!new_groups) { | |
162 | err = -ENOMEM; | |
163 | goto out; | |
164 | } | |
165 | mc_groups = new_groups; | |
166 | *mc_groups = mc_group_start; | |
167 | } else { | |
168 | new_groups = krealloc(mc_groups, nlen, GFP_KERNEL); | |
169 | if (!new_groups) { | |
170 | err = -ENOMEM; | |
171 | goto out; | |
172 | } | |
173 | mc_groups = new_groups; | |
174 | mc_groups[mc_groups_longs] = 0; | |
175 | } | |
176 | mc_groups_longs++; | |
177 | } | |
178 | ||
134e6375 JB |
179 | if (family->netnsok) { |
180 | struct net *net; | |
181 | ||
d136f1bd | 182 | netlink_table_grab(); |
134e6375 JB |
183 | rcu_read_lock(); |
184 | for_each_net_rcu(net) { | |
d136f1bd | 185 | err = __netlink_change_ngroups(net->genl_sock, |
134e6375 JB |
186 | mc_groups_longs * BITS_PER_LONG); |
187 | if (err) { | |
188 | /* | |
189 | * No need to roll back, can only fail if | |
190 | * memory allocation fails and then the | |
191 | * number of _possible_ groups has been | |
192 | * increased on some sockets which is ok. | |
193 | */ | |
194 | rcu_read_unlock(); | |
d136f1bd | 195 | netlink_table_ungrab(); |
134e6375 JB |
196 | goto out; |
197 | } | |
198 | } | |
199 | rcu_read_unlock(); | |
d136f1bd | 200 | netlink_table_ungrab(); |
134e6375 JB |
201 | } else { |
202 | err = netlink_change_ngroups(init_net.genl_sock, | |
203 | mc_groups_longs * BITS_PER_LONG); | |
204 | if (err) | |
205 | goto out; | |
206 | } | |
2dbba6f7 JB |
207 | |
208 | grp->id = id; | |
209 | set_bit(id, mc_groups); | |
210 | list_add_tail(&grp->list, &family->mcast_groups); | |
211 | grp->family = family; | |
212 | ||
213 | genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, grp); | |
214 | out: | |
215 | genl_unlock(); | |
79d310d0 | 216 | return err; |
2dbba6f7 JB |
217 | } |
218 | EXPORT_SYMBOL(genl_register_mc_group); | |
219 | ||
79dc4386 TG |
220 | static void __genl_unregister_mc_group(struct genl_family *family, |
221 | struct genl_multicast_group *grp) | |
222 | { | |
134e6375 | 223 | struct net *net; |
79dc4386 | 224 | BUG_ON(grp->family != family); |
134e6375 | 225 | |
b8273570 | 226 | netlink_table_grab(); |
134e6375 JB |
227 | rcu_read_lock(); |
228 | for_each_net_rcu(net) | |
b8273570 | 229 | __netlink_clear_multicast_users(net->genl_sock, grp->id); |
134e6375 | 230 | rcu_read_unlock(); |
b8273570 | 231 | netlink_table_ungrab(); |
134e6375 | 232 | |
79dc4386 TG |
233 | clear_bit(grp->id, mc_groups); |
234 | list_del(&grp->list); | |
235 | genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, grp); | |
236 | grp->id = 0; | |
237 | grp->family = NULL; | |
238 | } | |
239 | ||
2dbba6f7 JB |
240 | /** |
241 | * genl_unregister_mc_group - unregister a multicast group | |
242 | * | |
243 | * Unregisters the specified multicast group and notifies userspace | |
244 | * about it. All current listeners on the group are removed. | |
245 | * | |
246 | * Note: It is not necessary to unregister all multicast groups before | |
247 | * unregistering the family, unregistering the family will cause | |
248 | * all assigned multicast groups to be unregistered automatically. | |
249 | * | |
250 | * @family: Generic netlink family the group belongs to. | |
251 | * @grp: The group to unregister, must have been registered successfully | |
252 | * previously. | |
253 | */ | |
254 | void genl_unregister_mc_group(struct genl_family *family, | |
255 | struct genl_multicast_group *grp) | |
256 | { | |
2dbba6f7 | 257 | genl_lock(); |
79dc4386 | 258 | __genl_unregister_mc_group(family, grp); |
2dbba6f7 JB |
259 | genl_unlock(); |
260 | } | |
3efb40c2 | 261 | EXPORT_SYMBOL(genl_unregister_mc_group); |
2dbba6f7 JB |
262 | |
263 | static void genl_unregister_mc_groups(struct genl_family *family) | |
264 | { | |
265 | struct genl_multicast_group *grp, *tmp; | |
266 | ||
267 | list_for_each_entry_safe(grp, tmp, &family->mcast_groups, list) | |
79dc4386 | 268 | __genl_unregister_mc_group(family, grp); |
2dbba6f7 JB |
269 | } |
270 | ||
482a8524 TG |
271 | /** |
272 | * genl_register_ops - register generic netlink operations | |
273 | * @family: generic netlink family | |
274 | * @ops: operations to be registered | |
275 | * | |
276 | * Registers the specified operations and assigns them to the specified | |
277 | * family. Either a doit or dumpit callback must be specified or the | |
278 | * operation will fail. Only one operation structure per command | |
279 | * identifier may be registered. | |
280 | * | |
281 | * See include/net/genetlink.h for more documenation on the operations | |
282 | * structure. | |
283 | * | |
284 | * Returns 0 on success or a negative error code. | |
285 | */ | |
286 | int genl_register_ops(struct genl_family *family, struct genl_ops *ops) | |
287 | { | |
288 | int err = -EINVAL; | |
289 | ||
290 | if (ops->dumpit == NULL && ops->doit == NULL) | |
291 | goto errout; | |
292 | ||
293 | if (genl_get_cmd(ops->cmd, family)) { | |
294 | err = -EEXIST; | |
295 | goto errout; | |
296 | } | |
297 | ||
334c29a6 | 298 | if (ops->dumpit) |
334c29a6 | 299 | ops->flags |= GENL_CMD_CAP_DUMP; |
48d4ed7a JHS |
300 | if (ops->doit) |
301 | ops->flags |= GENL_CMD_CAP_DO; | |
334c29a6 JHS |
302 | if (ops->policy) |
303 | ops->flags |= GENL_CMD_CAP_HASPOL; | |
304 | ||
482a8524 TG |
305 | genl_lock(); |
306 | list_add_tail(&ops->ops_list, &family->ops_list); | |
307 | genl_unlock(); | |
308 | ||
309 | genl_ctrl_event(CTRL_CMD_NEWOPS, ops); | |
310 | err = 0; | |
311 | errout: | |
312 | return err; | |
313 | } | |
416c2f9c | 314 | EXPORT_SYMBOL(genl_register_ops); |
482a8524 TG |
315 | |
316 | /** | |
317 | * genl_unregister_ops - unregister generic netlink operations | |
318 | * @family: generic netlink family | |
319 | * @ops: operations to be unregistered | |
320 | * | |
321 | * Unregisters the specified operations and unassigns them from the | |
322 | * specified family. The operation blocks until the current message | |
323 | * processing has finished and doesn't start again until the | |
324 | * unregister process has finished. | |
325 | * | |
326 | * Note: It is not necessary to unregister all operations before | |
327 | * unregistering the family, unregistering the family will cause | |
328 | * all assigned operations to be unregistered automatically. | |
329 | * | |
330 | * Returns 0 on success or a negative error code. | |
331 | */ | |
332 | int genl_unregister_ops(struct genl_family *family, struct genl_ops *ops) | |
333 | { | |
334 | struct genl_ops *rc; | |
335 | ||
336 | genl_lock(); | |
337 | list_for_each_entry(rc, &family->ops_list, ops_list) { | |
338 | if (rc == ops) { | |
339 | list_del(&ops->ops_list); | |
340 | genl_unlock(); | |
341 | genl_ctrl_event(CTRL_CMD_DELOPS, ops); | |
342 | return 0; | |
343 | } | |
344 | } | |
345 | genl_unlock(); | |
346 | ||
347 | return -ENOENT; | |
348 | } | |
416c2f9c | 349 | EXPORT_SYMBOL(genl_unregister_ops); |
482a8524 TG |
350 | |
351 | /** | |
352 | * genl_register_family - register a generic netlink family | |
353 | * @family: generic netlink family | |
354 | * | |
355 | * Registers the specified family after validating it first. Only one | |
356 | * family may be registered with the same family name or identifier. | |
357 | * The family id may equal GENL_ID_GENERATE causing an unique id to | |
358 | * be automatically generated and assigned. | |
359 | * | |
360 | * Return 0 on success or a negative error code. | |
361 | */ | |
362 | int genl_register_family(struct genl_family *family) | |
363 | { | |
364 | int err = -EINVAL; | |
365 | ||
366 | if (family->id && family->id < GENL_MIN_ID) | |
367 | goto errout; | |
368 | ||
369 | if (family->id > GENL_MAX_ID) | |
370 | goto errout; | |
371 | ||
372 | INIT_LIST_HEAD(&family->ops_list); | |
2dbba6f7 | 373 | INIT_LIST_HEAD(&family->mcast_groups); |
482a8524 TG |
374 | |
375 | genl_lock(); | |
376 | ||
377 | if (genl_family_find_byname(family->name)) { | |
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; | |
93860b08 KK |
391 | } else if (genl_family_find_byid(family->id)) { |
392 | err = -EEXIST; | |
393 | goto errout_locked; | |
482a8524 TG |
394 | } |
395 | ||
396 | if (family->maxattr) { | |
397 | family->attrbuf = kmalloc((family->maxattr+1) * | |
398 | sizeof(struct nlattr *), GFP_KERNEL); | |
399 | if (family->attrbuf == NULL) { | |
400 | err = -ENOMEM; | |
e200bd80 | 401 | goto errout_locked; |
482a8524 TG |
402 | } |
403 | } else | |
404 | family->attrbuf = NULL; | |
405 | ||
406 | list_add_tail(&family->family_list, genl_family_chain(family->id)); | |
407 | genl_unlock(); | |
408 | ||
409 | genl_ctrl_event(CTRL_CMD_NEWFAMILY, family); | |
410 | ||
411 | return 0; | |
412 | ||
413 | errout_locked: | |
414 | genl_unlock(); | |
415 | errout: | |
416 | return err; | |
417 | } | |
416c2f9c | 418 | EXPORT_SYMBOL(genl_register_family); |
482a8524 | 419 | |
a7b11d73 MM |
420 | /** |
421 | * genl_register_family_with_ops - register a generic netlink family | |
422 | * @family: generic netlink family | |
423 | * @ops: operations to be registered | |
424 | * @n_ops: number of elements to register | |
425 | * | |
426 | * Registers the specified family and operations from the specified table. | |
427 | * Only one family may be registered with the same family name or identifier. | |
428 | * | |
429 | * The family id may equal GENL_ID_GENERATE causing an unique id to | |
430 | * be automatically generated and assigned. | |
431 | * | |
432 | * Either a doit or dumpit callback must be specified for every registered | |
433 | * operation or the function will fail. Only one operation structure per | |
434 | * command identifier may be registered. | |
435 | * | |
436 | * See include/net/genetlink.h for more documenation on the operations | |
437 | * structure. | |
438 | * | |
439 | * This is equivalent to calling genl_register_family() followed by | |
440 | * genl_register_ops() for every operation entry in the table taking | |
441 | * care to unregister the family on error path. | |
442 | * | |
443 | * Return 0 on success or a negative error code. | |
444 | */ | |
445 | int genl_register_family_with_ops(struct genl_family *family, | |
446 | struct genl_ops *ops, size_t n_ops) | |
447 | { | |
448 | int err, i; | |
449 | ||
450 | err = genl_register_family(family); | |
451 | if (err) | |
452 | return err; | |
453 | ||
454 | for (i = 0; i < n_ops; ++i, ++ops) { | |
455 | err = genl_register_ops(family, ops); | |
456 | if (err) | |
457 | goto err_out; | |
458 | } | |
459 | return 0; | |
460 | err_out: | |
461 | genl_unregister_family(family); | |
462 | return err; | |
463 | } | |
464 | EXPORT_SYMBOL(genl_register_family_with_ops); | |
465 | ||
482a8524 TG |
466 | /** |
467 | * genl_unregister_family - unregister generic netlink family | |
468 | * @family: generic netlink family | |
469 | * | |
470 | * Unregisters the specified family. | |
471 | * | |
472 | * Returns 0 on success or a negative error code. | |
473 | */ | |
474 | int genl_unregister_family(struct genl_family *family) | |
475 | { | |
476 | struct genl_family *rc; | |
477 | ||
478 | genl_lock(); | |
479 | ||
910d6c32 PE |
480 | genl_unregister_mc_groups(family); |
481 | ||
482a8524 TG |
482 | list_for_each_entry(rc, genl_family_chain(family->id), family_list) { |
483 | if (family->id != rc->id || strcmp(rc->name, family->name)) | |
484 | continue; | |
485 | ||
486 | list_del(&rc->family_list); | |
487 | INIT_LIST_HEAD(&family->ops_list); | |
488 | genl_unlock(); | |
489 | ||
482a8524 TG |
490 | kfree(family->attrbuf); |
491 | genl_ctrl_event(CTRL_CMD_DELFAMILY, family); | |
492 | return 0; | |
493 | } | |
494 | ||
495 | genl_unlock(); | |
496 | ||
497 | return -ENOENT; | |
498 | } | |
416c2f9c | 499 | EXPORT_SYMBOL(genl_unregister_family); |
482a8524 | 500 | |
1d00a4eb | 501 | static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) |
482a8524 TG |
502 | { |
503 | struct genl_ops *ops; | |
504 | struct genl_family *family; | |
134e6375 | 505 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
506 | struct genl_info info; |
507 | struct genlmsghdr *hdr = nlmsg_data(nlh); | |
1d00a4eb | 508 | int hdrlen, err; |
482a8524 | 509 | |
746fac4d | 510 | family = genl_family_find_byid(nlh->nlmsg_type); |
1d00a4eb TG |
511 | if (family == NULL) |
512 | return -ENOENT; | |
482a8524 | 513 | |
134e6375 JB |
514 | /* this family doesn't exist in this netns */ |
515 | if (!family->netnsok && !net_eq(net, &init_net)) | |
516 | return -ENOENT; | |
517 | ||
482a8524 TG |
518 | hdrlen = GENL_HDRLEN + family->hdrsize; |
519 | if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) | |
1d00a4eb | 520 | return -EINVAL; |
482a8524 TG |
521 | |
522 | ops = genl_get_cmd(hdr->cmd, family); | |
1d00a4eb TG |
523 | if (ops == NULL) |
524 | return -EOPNOTSUPP; | |
482a8524 | 525 | |
1d00a4eb | 526 | if ((ops->flags & GENL_ADMIN_PERM) && |
fd778461 | 527 | !capable(CAP_NET_ADMIN)) |
1d00a4eb | 528 | return -EPERM; |
482a8524 | 529 | |
b8f3ab42 | 530 | if (nlh->nlmsg_flags & NLM_F_DUMP) { |
1d00a4eb TG |
531 | if (ops->dumpit == NULL) |
532 | return -EOPNOTSUPP; | |
482a8524 | 533 | |
6d1a3fb5 | 534 | genl_unlock(); |
134e6375 | 535 | err = netlink_dump_start(net->genl_sock, skb, nlh, |
c7ac8679 | 536 | ops->dumpit, ops->done, 0); |
6d1a3fb5 PM |
537 | genl_lock(); |
538 | return err; | |
482a8524 TG |
539 | } |
540 | ||
1d00a4eb TG |
541 | if (ops->doit == NULL) |
542 | return -EOPNOTSUPP; | |
482a8524 TG |
543 | |
544 | if (family->attrbuf) { | |
545 | err = nlmsg_parse(nlh, hdrlen, family->attrbuf, family->maxattr, | |
546 | ops->policy); | |
547 | if (err < 0) | |
1d00a4eb | 548 | return err; |
482a8524 TG |
549 | } |
550 | ||
551 | info.snd_seq = nlh->nlmsg_seq; | |
552 | info.snd_pid = NETLINK_CB(skb).pid; | |
553 | info.nlhdr = nlh; | |
554 | info.genlhdr = nlmsg_data(nlh); | |
555 | info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN; | |
556 | info.attrs = family->attrbuf; | |
134e6375 | 557 | genl_info_net_set(&info, net); |
ff4c92d8 | 558 | memset(&info.user_ptr, 0, sizeof(info.user_ptr)); |
482a8524 | 559 | |
ff4c92d8 JB |
560 | if (family->pre_doit) { |
561 | err = family->pre_doit(ops, skb, &info); | |
562 | if (err) | |
563 | return err; | |
564 | } | |
565 | ||
566 | err = ops->doit(skb, &info); | |
567 | ||
568 | if (family->post_doit) | |
569 | family->post_doit(ops, skb, &info); | |
570 | ||
571 | return err; | |
482a8524 TG |
572 | } |
573 | ||
cd40b7d3 | 574 | static void genl_rcv(struct sk_buff *skb) |
482a8524 | 575 | { |
cd40b7d3 DL |
576 | genl_lock(); |
577 | netlink_rcv_skb(skb, &genl_rcv_msg); | |
578 | genl_unlock(); | |
482a8524 TG |
579 | } |
580 | ||
581 | /************************************************************************** | |
582 | * Controller | |
583 | **************************************************************************/ | |
584 | ||
17c157c8 TG |
585 | static struct genl_family genl_ctrl = { |
586 | .id = GENL_ID_CTRL, | |
587 | .name = "nlctrl", | |
334c29a6 | 588 | .version = 0x2, |
17c157c8 | 589 | .maxattr = CTRL_ATTR_MAX, |
134e6375 | 590 | .netnsok = true, |
17c157c8 TG |
591 | }; |
592 | ||
482a8524 TG |
593 | static int ctrl_fill_info(struct genl_family *family, u32 pid, u32 seq, |
594 | u32 flags, struct sk_buff *skb, u8 cmd) | |
595 | { | |
596 | void *hdr; | |
597 | ||
17c157c8 | 598 | hdr = genlmsg_put(skb, pid, seq, &genl_ctrl, flags, cmd); |
482a8524 TG |
599 | if (hdr == NULL) |
600 | return -1; | |
601 | ||
602 | NLA_PUT_STRING(skb, CTRL_ATTR_FAMILY_NAME, family->name); | |
603 | NLA_PUT_U16(skb, CTRL_ATTR_FAMILY_ID, family->id); | |
eb328111 TG |
604 | NLA_PUT_U32(skb, CTRL_ATTR_VERSION, family->version); |
605 | NLA_PUT_U32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize); | |
606 | NLA_PUT_U32(skb, CTRL_ATTR_MAXATTR, family->maxattr); | |
607 | ||
e94ef682 TG |
608 | if (!list_empty(&family->ops_list)) { |
609 | struct nlattr *nla_ops; | |
610 | struct genl_ops *ops; | |
611 | int idx = 1; | |
eb328111 | 612 | |
e94ef682 TG |
613 | nla_ops = nla_nest_start(skb, CTRL_ATTR_OPS); |
614 | if (nla_ops == NULL) | |
eb328111 TG |
615 | goto nla_put_failure; |
616 | ||
e94ef682 TG |
617 | list_for_each_entry(ops, &family->ops_list, ops_list) { |
618 | struct nlattr *nest; | |
eb328111 | 619 | |
e94ef682 TG |
620 | nest = nla_nest_start(skb, idx++); |
621 | if (nest == NULL) | |
622 | goto nla_put_failure; | |
eb328111 | 623 | |
e94ef682 TG |
624 | NLA_PUT_U32(skb, CTRL_ATTR_OP_ID, ops->cmd); |
625 | NLA_PUT_U32(skb, CTRL_ATTR_OP_FLAGS, ops->flags); | |
eb328111 | 626 | |
e94ef682 TG |
627 | nla_nest_end(skb, nest); |
628 | } | |
629 | ||
630 | nla_nest_end(skb, nla_ops); | |
631 | } | |
482a8524 | 632 | |
2dbba6f7 JB |
633 | if (!list_empty(&family->mcast_groups)) { |
634 | struct genl_multicast_group *grp; | |
635 | struct nlattr *nla_grps; | |
636 | int idx = 1; | |
637 | ||
638 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
639 | if (nla_grps == NULL) | |
640 | goto nla_put_failure; | |
641 | ||
642 | list_for_each_entry(grp, &family->mcast_groups, list) { | |
643 | struct nlattr *nest; | |
644 | ||
645 | nest = nla_nest_start(skb, idx++); | |
646 | if (nest == NULL) | |
647 | goto nla_put_failure; | |
648 | ||
649 | NLA_PUT_U32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id); | |
650 | NLA_PUT_STRING(skb, CTRL_ATTR_MCAST_GRP_NAME, | |
651 | grp->name); | |
652 | ||
653 | nla_nest_end(skb, nest); | |
654 | } | |
655 | nla_nest_end(skb, nla_grps); | |
656 | } | |
657 | ||
658 | return genlmsg_end(skb, hdr); | |
659 | ||
660 | nla_put_failure: | |
bc3ed28c TG |
661 | genlmsg_cancel(skb, hdr); |
662 | return -EMSGSIZE; | |
2dbba6f7 JB |
663 | } |
664 | ||
665 | static int ctrl_fill_mcgrp_info(struct genl_multicast_group *grp, u32 pid, | |
666 | u32 seq, u32 flags, struct sk_buff *skb, | |
667 | u8 cmd) | |
668 | { | |
669 | void *hdr; | |
670 | struct nlattr *nla_grps; | |
671 | struct nlattr *nest; | |
672 | ||
673 | hdr = genlmsg_put(skb, pid, seq, &genl_ctrl, flags, cmd); | |
674 | if (hdr == NULL) | |
675 | return -1; | |
676 | ||
677 | NLA_PUT_STRING(skb, CTRL_ATTR_FAMILY_NAME, grp->family->name); | |
678 | NLA_PUT_U16(skb, CTRL_ATTR_FAMILY_ID, grp->family->id); | |
679 | ||
680 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
681 | if (nla_grps == NULL) | |
682 | goto nla_put_failure; | |
683 | ||
684 | nest = nla_nest_start(skb, 1); | |
685 | if (nest == NULL) | |
686 | goto nla_put_failure; | |
687 | ||
688 | NLA_PUT_U32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id); | |
689 | NLA_PUT_STRING(skb, CTRL_ATTR_MCAST_GRP_NAME, | |
690 | grp->name); | |
691 | ||
692 | nla_nest_end(skb, nest); | |
693 | nla_nest_end(skb, nla_grps); | |
694 | ||
482a8524 TG |
695 | return genlmsg_end(skb, hdr); |
696 | ||
697 | nla_put_failure: | |
bc3ed28c TG |
698 | genlmsg_cancel(skb, hdr); |
699 | return -EMSGSIZE; | |
482a8524 TG |
700 | } |
701 | ||
702 | static int ctrl_dumpfamily(struct sk_buff *skb, struct netlink_callback *cb) | |
703 | { | |
704 | ||
705 | int i, n = 0; | |
706 | struct genl_family *rt; | |
134e6375 | 707 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
708 | int chains_to_skip = cb->args[0]; |
709 | int fams_to_skip = cb->args[1]; | |
710 | ||
e1d5a010 | 711 | for (i = chains_to_skip; i < GENL_FAM_TAB_SIZE; i++) { |
482a8524 TG |
712 | n = 0; |
713 | list_for_each_entry(rt, genl_family_chain(i), family_list) { | |
134e6375 JB |
714 | if (!rt->netnsok && !net_eq(net, &init_net)) |
715 | continue; | |
482a8524 TG |
716 | if (++n < fams_to_skip) |
717 | continue; | |
718 | if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).pid, | |
719 | cb->nlh->nlmsg_seq, NLM_F_MULTI, | |
720 | skb, CTRL_CMD_NEWFAMILY) < 0) | |
721 | goto errout; | |
722 | } | |
723 | ||
724 | fams_to_skip = 0; | |
725 | } | |
726 | ||
727 | errout: | |
728 | cb->args[0] = i; | |
729 | cb->args[1] = n; | |
730 | ||
731 | return skb->len; | |
732 | } | |
733 | ||
2dbba6f7 JB |
734 | static struct sk_buff *ctrl_build_family_msg(struct genl_family *family, |
735 | u32 pid, int seq, u8 cmd) | |
482a8524 TG |
736 | { |
737 | struct sk_buff *skb; | |
738 | int err; | |
739 | ||
339bf98f | 740 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); |
482a8524 TG |
741 | if (skb == NULL) |
742 | return ERR_PTR(-ENOBUFS); | |
743 | ||
744 | err = ctrl_fill_info(family, pid, seq, 0, skb, cmd); | |
745 | if (err < 0) { | |
746 | nlmsg_free(skb); | |
747 | return ERR_PTR(err); | |
748 | } | |
749 | ||
750 | return skb; | |
751 | } | |
752 | ||
2dbba6f7 JB |
753 | static struct sk_buff *ctrl_build_mcgrp_msg(struct genl_multicast_group *grp, |
754 | u32 pid, int seq, u8 cmd) | |
755 | { | |
756 | struct sk_buff *skb; | |
757 | int err; | |
758 | ||
759 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); | |
760 | if (skb == NULL) | |
761 | return ERR_PTR(-ENOBUFS); | |
762 | ||
763 | err = ctrl_fill_mcgrp_info(grp, pid, seq, 0, skb, cmd); | |
764 | if (err < 0) { | |
765 | nlmsg_free(skb); | |
766 | return ERR_PTR(err); | |
767 | } | |
768 | ||
769 | return skb; | |
770 | } | |
771 | ||
ef7c79ed | 772 | static const struct nla_policy ctrl_policy[CTRL_ATTR_MAX+1] = { |
482a8524 | 773 | [CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 }, |
5176f91e TG |
774 | [CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING, |
775 | .len = GENL_NAMSIZ - 1 }, | |
482a8524 TG |
776 | }; |
777 | ||
778 | static int ctrl_getfamily(struct sk_buff *skb, struct genl_info *info) | |
779 | { | |
780 | struct sk_buff *msg; | |
781 | struct genl_family *res = NULL; | |
782 | int err = -EINVAL; | |
783 | ||
784 | if (info->attrs[CTRL_ATTR_FAMILY_ID]) { | |
785 | u16 id = nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]); | |
786 | res = genl_family_find_byid(id); | |
134e6375 | 787 | err = -ENOENT; |
482a8524 TG |
788 | } |
789 | ||
790 | if (info->attrs[CTRL_ATTR_FAMILY_NAME]) { | |
5176f91e | 791 | char *name; |
482a8524 | 792 | |
5176f91e | 793 | name = nla_data(info->attrs[CTRL_ATTR_FAMILY_NAME]); |
482a8524 | 794 | res = genl_family_find_byname(name); |
fa843095 SH |
795 | #ifdef CONFIG_MODULES |
796 | if (res == NULL) { | |
797 | genl_unlock(); | |
798 | request_module("net-pf-%d-proto-%d-type-%s", | |
799 | PF_NETLINK, NETLINK_GENERIC, name); | |
800 | genl_lock(); | |
801 | res = genl_family_find_byname(name); | |
802 | } | |
803 | #endif | |
134e6375 | 804 | err = -ENOENT; |
482a8524 TG |
805 | } |
806 | ||
134e6375 JB |
807 | if (res == NULL) |
808 | return err; | |
809 | ||
810 | if (!res->netnsok && !net_eq(genl_info_net(info), &init_net)) { | |
811 | /* family doesn't exist here */ | |
812 | return -ENOENT; | |
482a8524 TG |
813 | } |
814 | ||
2dbba6f7 JB |
815 | msg = ctrl_build_family_msg(res, info->snd_pid, info->snd_seq, |
816 | CTRL_CMD_NEWFAMILY); | |
134e6375 JB |
817 | if (IS_ERR(msg)) |
818 | return PTR_ERR(msg); | |
482a8524 | 819 | |
134e6375 | 820 | return genlmsg_reply(msg, info); |
482a8524 TG |
821 | } |
822 | ||
823 | static int genl_ctrl_event(int event, void *data) | |
824 | { | |
825 | struct sk_buff *msg; | |
134e6375 JB |
826 | struct genl_family *family; |
827 | struct genl_multicast_group *grp; | |
482a8524 | 828 | |
134e6375 JB |
829 | /* genl is still initialising */ |
830 | if (!init_net.genl_sock) | |
482a8524 TG |
831 | return 0; |
832 | ||
833 | switch (event) { | |
834 | case CTRL_CMD_NEWFAMILY: | |
835 | case CTRL_CMD_DELFAMILY: | |
134e6375 JB |
836 | family = data; |
837 | msg = ctrl_build_family_msg(family, 0, 0, event); | |
2dbba6f7 JB |
838 | break; |
839 | case CTRL_CMD_NEWMCAST_GRP: | |
840 | case CTRL_CMD_DELMCAST_GRP: | |
134e6375 JB |
841 | grp = data; |
842 | family = grp->family; | |
2dbba6f7 | 843 | msg = ctrl_build_mcgrp_msg(data, 0, 0, event); |
482a8524 | 844 | break; |
134e6375 JB |
845 | default: |
846 | return -EINVAL; | |
847 | } | |
848 | ||
849 | if (IS_ERR(msg)) | |
850 | return PTR_ERR(msg); | |
851 | ||
852 | if (!family->netnsok) { | |
853 | genlmsg_multicast_netns(&init_net, msg, 0, | |
854 | GENL_ID_CTRL, GFP_KERNEL); | |
855 | } else { | |
856 | rcu_read_lock(); | |
857 | genlmsg_multicast_allns(msg, 0, GENL_ID_CTRL, GFP_ATOMIC); | |
858 | rcu_read_unlock(); | |
482a8524 TG |
859 | } |
860 | ||
861 | return 0; | |
862 | } | |
863 | ||
864 | static struct genl_ops genl_ctrl_ops = { | |
865 | .cmd = CTRL_CMD_GETFAMILY, | |
866 | .doit = ctrl_getfamily, | |
867 | .dumpit = ctrl_dumpfamily, | |
868 | .policy = ctrl_policy, | |
869 | }; | |
870 | ||
2dbba6f7 JB |
871 | static struct genl_multicast_group notify_grp = { |
872 | .name = "notify", | |
873 | }; | |
874 | ||
134e6375 JB |
875 | static int __net_init genl_pernet_init(struct net *net) |
876 | { | |
877 | /* we'll bump the group number right afterwards */ | |
878 | net->genl_sock = netlink_kernel_create(net, NETLINK_GENERIC, 0, | |
879 | genl_rcv, &genl_mutex, | |
880 | THIS_MODULE); | |
881 | ||
882 | if (!net->genl_sock && net_eq(net, &init_net)) | |
883 | panic("GENL: Cannot initialize generic netlink\n"); | |
884 | ||
885 | if (!net->genl_sock) | |
886 | return -ENOMEM; | |
887 | ||
888 | return 0; | |
889 | } | |
890 | ||
891 | static void __net_exit genl_pernet_exit(struct net *net) | |
892 | { | |
893 | netlink_kernel_release(net->genl_sock); | |
894 | net->genl_sock = NULL; | |
895 | } | |
896 | ||
897 | static struct pernet_operations genl_pernet_ops = { | |
898 | .init = genl_pernet_init, | |
899 | .exit = genl_pernet_exit, | |
900 | }; | |
901 | ||
482a8524 TG |
902 | static int __init genl_init(void) |
903 | { | |
904 | int i, err; | |
905 | ||
906 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) | |
907 | INIT_LIST_HEAD(&family_ht[i]); | |
908 | ||
652c6717 | 909 | err = genl_register_family_with_ops(&genl_ctrl, &genl_ctrl_ops, 1); |
482a8524 | 910 | if (err < 0) |
134e6375 | 911 | goto problem; |
482a8524 TG |
912 | |
913 | netlink_set_nonroot(NETLINK_GENERIC, NL_NONROOT_RECV); | |
2dbba6f7 | 914 | |
134e6375 JB |
915 | err = register_pernet_subsys(&genl_pernet_ops); |
916 | if (err) | |
917 | goto problem; | |
482a8524 | 918 | |
2dbba6f7 JB |
919 | err = genl_register_mc_group(&genl_ctrl, ¬ify_grp); |
920 | if (err < 0) | |
134e6375 | 921 | goto problem; |
2dbba6f7 | 922 | |
482a8524 TG |
923 | return 0; |
924 | ||
134e6375 | 925 | problem: |
482a8524 | 926 | panic("GENL: Cannot register controller: %d\n", err); |
482a8524 TG |
927 | } |
928 | ||
929 | subsys_initcall(genl_init); | |
930 | ||
134e6375 JB |
931 | static int genlmsg_mcast(struct sk_buff *skb, u32 pid, unsigned long group, |
932 | gfp_t flags) | |
933 | { | |
934 | struct sk_buff *tmp; | |
935 | struct net *net, *prev = NULL; | |
936 | int err; | |
937 | ||
938 | for_each_net_rcu(net) { | |
939 | if (prev) { | |
940 | tmp = skb_clone(skb, flags); | |
941 | if (!tmp) { | |
942 | err = -ENOMEM; | |
943 | goto error; | |
944 | } | |
945 | err = nlmsg_multicast(prev->genl_sock, tmp, | |
946 | pid, group, flags); | |
947 | if (err) | |
948 | goto error; | |
949 | } | |
950 | ||
951 | prev = net; | |
952 | } | |
953 | ||
954 | return nlmsg_multicast(prev->genl_sock, skb, pid, group, flags); | |
955 | error: | |
956 | kfree_skb(skb); | |
957 | return err; | |
958 | } | |
959 | ||
960 | int genlmsg_multicast_allns(struct sk_buff *skb, u32 pid, unsigned int group, | |
961 | gfp_t flags) | |
962 | { | |
963 | return genlmsg_mcast(skb, pid, group, flags); | |
964 | } | |
965 | EXPORT_SYMBOL(genlmsg_multicast_allns); | |
263ba61d PS |
966 | |
967 | void genl_notify(struct sk_buff *skb, struct net *net, u32 pid, u32 group, | |
968 | struct nlmsghdr *nlh, gfp_t flags) | |
969 | { | |
970 | struct sock *sk = net->genl_sock; | |
971 | int report = 0; | |
972 | ||
973 | if (nlh) | |
974 | report = nlmsg_report(nlh); | |
975 | ||
976 | nlmsg_notify(sk, skb, pid, group, report, flags); | |
977 | } | |
978 | EXPORT_SYMBOL(genl_notify); |