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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 | |
320f5ea0 | 36 | #ifdef CONFIG_LOCKDEP |
86b1309c PS |
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'); | |
f1e79e20 | 145 | BUG_ON(memchr(grp->name, '\0', GENL_NAMSIZ) == NULL); |
2dbba6f7 JB |
146 | |
147 | genl_lock(); | |
148 | ||
149 | /* special-case our own group */ | |
150 | if (grp == ¬ify_grp) | |
151 | id = GENL_ID_CTRL; | |
152 | else | |
153 | id = find_first_zero_bit(mc_groups, | |
154 | mc_groups_longs * BITS_PER_LONG); | |
155 | ||
156 | ||
157 | if (id >= mc_groups_longs * BITS_PER_LONG) { | |
158 | size_t nlen = (mc_groups_longs + 1) * sizeof(unsigned long); | |
159 | ||
160 | if (mc_groups == &mc_group_start) { | |
161 | new_groups = kzalloc(nlen, GFP_KERNEL); | |
162 | if (!new_groups) { | |
163 | err = -ENOMEM; | |
164 | goto out; | |
165 | } | |
166 | mc_groups = new_groups; | |
167 | *mc_groups = mc_group_start; | |
168 | } else { | |
169 | new_groups = krealloc(mc_groups, nlen, GFP_KERNEL); | |
170 | if (!new_groups) { | |
171 | err = -ENOMEM; | |
172 | goto out; | |
173 | } | |
174 | mc_groups = new_groups; | |
175 | mc_groups[mc_groups_longs] = 0; | |
176 | } | |
177 | mc_groups_longs++; | |
178 | } | |
179 | ||
134e6375 JB |
180 | if (family->netnsok) { |
181 | struct net *net; | |
182 | ||
d136f1bd | 183 | netlink_table_grab(); |
134e6375 JB |
184 | rcu_read_lock(); |
185 | for_each_net_rcu(net) { | |
d136f1bd | 186 | err = __netlink_change_ngroups(net->genl_sock, |
134e6375 JB |
187 | mc_groups_longs * BITS_PER_LONG); |
188 | if (err) { | |
189 | /* | |
190 | * No need to roll back, can only fail if | |
191 | * memory allocation fails and then the | |
192 | * number of _possible_ groups has been | |
193 | * increased on some sockets which is ok. | |
194 | */ | |
195 | rcu_read_unlock(); | |
d136f1bd | 196 | netlink_table_ungrab(); |
134e6375 JB |
197 | goto out; |
198 | } | |
199 | } | |
200 | rcu_read_unlock(); | |
d136f1bd | 201 | netlink_table_ungrab(); |
134e6375 JB |
202 | } else { |
203 | err = netlink_change_ngroups(init_net.genl_sock, | |
204 | mc_groups_longs * BITS_PER_LONG); | |
205 | if (err) | |
206 | goto out; | |
207 | } | |
2dbba6f7 JB |
208 | |
209 | grp->id = id; | |
210 | set_bit(id, mc_groups); | |
211 | list_add_tail(&grp->list, &family->mcast_groups); | |
212 | grp->family = family; | |
213 | ||
214 | genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, grp); | |
215 | out: | |
216 | genl_unlock(); | |
79d310d0 | 217 | return err; |
2dbba6f7 JB |
218 | } |
219 | EXPORT_SYMBOL(genl_register_mc_group); | |
220 | ||
79dc4386 TG |
221 | static void __genl_unregister_mc_group(struct genl_family *family, |
222 | struct genl_multicast_group *grp) | |
223 | { | |
134e6375 | 224 | struct net *net; |
79dc4386 | 225 | BUG_ON(grp->family != family); |
134e6375 | 226 | |
b8273570 | 227 | netlink_table_grab(); |
134e6375 JB |
228 | rcu_read_lock(); |
229 | for_each_net_rcu(net) | |
b8273570 | 230 | __netlink_clear_multicast_users(net->genl_sock, grp->id); |
134e6375 | 231 | rcu_read_unlock(); |
b8273570 | 232 | netlink_table_ungrab(); |
134e6375 | 233 | |
79dc4386 TG |
234 | clear_bit(grp->id, mc_groups); |
235 | list_del(&grp->list); | |
236 | genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, grp); | |
237 | grp->id = 0; | |
238 | grp->family = NULL; | |
239 | } | |
240 | ||
2dbba6f7 JB |
241 | /** |
242 | * genl_unregister_mc_group - unregister a multicast group | |
243 | * | |
244 | * Unregisters the specified multicast group and notifies userspace | |
245 | * about it. All current listeners on the group are removed. | |
246 | * | |
247 | * Note: It is not necessary to unregister all multicast groups before | |
248 | * unregistering the family, unregistering the family will cause | |
249 | * all assigned multicast groups to be unregistered automatically. | |
250 | * | |
251 | * @family: Generic netlink family the group belongs to. | |
252 | * @grp: The group to unregister, must have been registered successfully | |
253 | * previously. | |
254 | */ | |
255 | void genl_unregister_mc_group(struct genl_family *family, | |
256 | struct genl_multicast_group *grp) | |
257 | { | |
2dbba6f7 | 258 | genl_lock(); |
79dc4386 | 259 | __genl_unregister_mc_group(family, grp); |
2dbba6f7 JB |
260 | genl_unlock(); |
261 | } | |
3efb40c2 | 262 | EXPORT_SYMBOL(genl_unregister_mc_group); |
2dbba6f7 JB |
263 | |
264 | static void genl_unregister_mc_groups(struct genl_family *family) | |
265 | { | |
266 | struct genl_multicast_group *grp, *tmp; | |
267 | ||
268 | list_for_each_entry_safe(grp, tmp, &family->mcast_groups, list) | |
79dc4386 | 269 | __genl_unregister_mc_group(family, grp); |
2dbba6f7 JB |
270 | } |
271 | ||
482a8524 TG |
272 | /** |
273 | * genl_register_ops - register generic netlink operations | |
274 | * @family: generic netlink family | |
275 | * @ops: operations to be registered | |
276 | * | |
277 | * Registers the specified operations and assigns them to the specified | |
278 | * family. Either a doit or dumpit callback must be specified or the | |
279 | * operation will fail. Only one operation structure per command | |
280 | * identifier may be registered. | |
281 | * | |
282 | * See include/net/genetlink.h for more documenation on the operations | |
283 | * structure. | |
284 | * | |
285 | * Returns 0 on success or a negative error code. | |
286 | */ | |
287 | int genl_register_ops(struct genl_family *family, struct genl_ops *ops) | |
288 | { | |
289 | int err = -EINVAL; | |
290 | ||
291 | if (ops->dumpit == NULL && ops->doit == NULL) | |
292 | goto errout; | |
293 | ||
294 | if (genl_get_cmd(ops->cmd, family)) { | |
295 | err = -EEXIST; | |
296 | goto errout; | |
297 | } | |
298 | ||
334c29a6 | 299 | if (ops->dumpit) |
334c29a6 | 300 | ops->flags |= GENL_CMD_CAP_DUMP; |
48d4ed7a JHS |
301 | if (ops->doit) |
302 | ops->flags |= GENL_CMD_CAP_DO; | |
334c29a6 JHS |
303 | if (ops->policy) |
304 | ops->flags |= GENL_CMD_CAP_HASPOL; | |
305 | ||
482a8524 TG |
306 | genl_lock(); |
307 | list_add_tail(&ops->ops_list, &family->ops_list); | |
308 | genl_unlock(); | |
309 | ||
310 | genl_ctrl_event(CTRL_CMD_NEWOPS, ops); | |
311 | err = 0; | |
312 | errout: | |
313 | return err; | |
314 | } | |
416c2f9c | 315 | EXPORT_SYMBOL(genl_register_ops); |
482a8524 TG |
316 | |
317 | /** | |
318 | * genl_unregister_ops - unregister generic netlink operations | |
319 | * @family: generic netlink family | |
320 | * @ops: operations to be unregistered | |
321 | * | |
322 | * Unregisters the specified operations and unassigns them from the | |
323 | * specified family. The operation blocks until the current message | |
324 | * processing has finished and doesn't start again until the | |
325 | * unregister process has finished. | |
326 | * | |
327 | * Note: It is not necessary to unregister all operations before | |
328 | * unregistering the family, unregistering the family will cause | |
329 | * all assigned operations to be unregistered automatically. | |
330 | * | |
331 | * Returns 0 on success or a negative error code. | |
332 | */ | |
333 | int genl_unregister_ops(struct genl_family *family, struct genl_ops *ops) | |
334 | { | |
335 | struct genl_ops *rc; | |
336 | ||
337 | genl_lock(); | |
338 | list_for_each_entry(rc, &family->ops_list, ops_list) { | |
339 | if (rc == ops) { | |
340 | list_del(&ops->ops_list); | |
341 | genl_unlock(); | |
342 | genl_ctrl_event(CTRL_CMD_DELOPS, ops); | |
343 | return 0; | |
344 | } | |
345 | } | |
346 | genl_unlock(); | |
347 | ||
348 | return -ENOENT; | |
349 | } | |
416c2f9c | 350 | EXPORT_SYMBOL(genl_unregister_ops); |
482a8524 TG |
351 | |
352 | /** | |
353 | * genl_register_family - register a generic netlink family | |
354 | * @family: generic netlink family | |
355 | * | |
356 | * Registers the specified family after validating it first. Only one | |
357 | * family may be registered with the same family name or identifier. | |
358 | * The family id may equal GENL_ID_GENERATE causing an unique id to | |
359 | * be automatically generated and assigned. | |
360 | * | |
361 | * Return 0 on success or a negative error code. | |
362 | */ | |
363 | int genl_register_family(struct genl_family *family) | |
364 | { | |
365 | int err = -EINVAL; | |
366 | ||
367 | if (family->id && family->id < GENL_MIN_ID) | |
368 | goto errout; | |
369 | ||
370 | if (family->id > GENL_MAX_ID) | |
371 | goto errout; | |
372 | ||
373 | INIT_LIST_HEAD(&family->ops_list); | |
2dbba6f7 | 374 | INIT_LIST_HEAD(&family->mcast_groups); |
482a8524 TG |
375 | |
376 | genl_lock(); | |
377 | ||
378 | if (genl_family_find_byname(family->name)) { | |
379 | err = -EEXIST; | |
380 | goto errout_locked; | |
381 | } | |
382 | ||
482a8524 TG |
383 | if (family->id == GENL_ID_GENERATE) { |
384 | u16 newid = genl_generate_id(); | |
385 | ||
386 | if (!newid) { | |
387 | err = -ENOMEM; | |
388 | goto errout_locked; | |
389 | } | |
390 | ||
391 | family->id = newid; | |
93860b08 KK |
392 | } else if (genl_family_find_byid(family->id)) { |
393 | err = -EEXIST; | |
394 | goto errout_locked; | |
482a8524 TG |
395 | } |
396 | ||
397 | if (family->maxattr) { | |
398 | family->attrbuf = kmalloc((family->maxattr+1) * | |
399 | sizeof(struct nlattr *), GFP_KERNEL); | |
400 | if (family->attrbuf == NULL) { | |
401 | err = -ENOMEM; | |
e200bd80 | 402 | goto errout_locked; |
482a8524 TG |
403 | } |
404 | } else | |
405 | family->attrbuf = NULL; | |
406 | ||
407 | list_add_tail(&family->family_list, genl_family_chain(family->id)); | |
408 | genl_unlock(); | |
409 | ||
410 | genl_ctrl_event(CTRL_CMD_NEWFAMILY, family); | |
411 | ||
412 | return 0; | |
413 | ||
414 | errout_locked: | |
415 | genl_unlock(); | |
416 | errout: | |
417 | return err; | |
418 | } | |
416c2f9c | 419 | EXPORT_SYMBOL(genl_register_family); |
482a8524 | 420 | |
a7b11d73 MM |
421 | /** |
422 | * genl_register_family_with_ops - register a generic netlink family | |
423 | * @family: generic netlink family | |
424 | * @ops: operations to be registered | |
425 | * @n_ops: number of elements to register | |
426 | * | |
427 | * Registers the specified family and operations from the specified table. | |
428 | * Only one family may be registered with the same family name or identifier. | |
429 | * | |
430 | * The family id may equal GENL_ID_GENERATE causing an unique id to | |
431 | * be automatically generated and assigned. | |
432 | * | |
433 | * Either a doit or dumpit callback must be specified for every registered | |
434 | * operation or the function will fail. Only one operation structure per | |
435 | * command identifier may be registered. | |
436 | * | |
437 | * See include/net/genetlink.h for more documenation on the operations | |
438 | * structure. | |
439 | * | |
440 | * This is equivalent to calling genl_register_family() followed by | |
441 | * genl_register_ops() for every operation entry in the table taking | |
442 | * care to unregister the family on error path. | |
443 | * | |
444 | * Return 0 on success or a negative error code. | |
445 | */ | |
446 | int genl_register_family_with_ops(struct genl_family *family, | |
447 | struct genl_ops *ops, size_t n_ops) | |
448 | { | |
449 | int err, i; | |
450 | ||
451 | err = genl_register_family(family); | |
452 | if (err) | |
453 | return err; | |
454 | ||
455 | for (i = 0; i < n_ops; ++i, ++ops) { | |
456 | err = genl_register_ops(family, ops); | |
457 | if (err) | |
458 | goto err_out; | |
459 | } | |
460 | return 0; | |
461 | err_out: | |
462 | genl_unregister_family(family); | |
463 | return err; | |
464 | } | |
465 | EXPORT_SYMBOL(genl_register_family_with_ops); | |
466 | ||
482a8524 TG |
467 | /** |
468 | * genl_unregister_family - unregister generic netlink family | |
469 | * @family: generic netlink family | |
470 | * | |
471 | * Unregisters the specified family. | |
472 | * | |
473 | * Returns 0 on success or a negative error code. | |
474 | */ | |
475 | int genl_unregister_family(struct genl_family *family) | |
476 | { | |
477 | struct genl_family *rc; | |
478 | ||
479 | genl_lock(); | |
480 | ||
910d6c32 PE |
481 | genl_unregister_mc_groups(family); |
482 | ||
482a8524 TG |
483 | list_for_each_entry(rc, genl_family_chain(family->id), family_list) { |
484 | if (family->id != rc->id || strcmp(rc->name, family->name)) | |
485 | continue; | |
486 | ||
487 | list_del(&rc->family_list); | |
488 | INIT_LIST_HEAD(&family->ops_list); | |
489 | genl_unlock(); | |
490 | ||
482a8524 TG |
491 | kfree(family->attrbuf); |
492 | genl_ctrl_event(CTRL_CMD_DELFAMILY, family); | |
493 | return 0; | |
494 | } | |
495 | ||
496 | genl_unlock(); | |
497 | ||
498 | return -ENOENT; | |
499 | } | |
416c2f9c | 500 | EXPORT_SYMBOL(genl_unregister_family); |
482a8524 | 501 | |
a46621a3 DV |
502 | /** |
503 | * genlmsg_put - Add generic netlink header to netlink message | |
504 | * @skb: socket buffer holding the message | |
15e47304 | 505 | * @portid: netlink portid the message is addressed to |
a46621a3 DV |
506 | * @seq: sequence number (usually the one of the sender) |
507 | * @family: generic netlink family | |
2c53040f | 508 | * @flags: netlink message flags |
a46621a3 DV |
509 | * @cmd: generic netlink command |
510 | * | |
511 | * Returns pointer to user specific header | |
512 | */ | |
15e47304 | 513 | void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, |
a46621a3 DV |
514 | struct genl_family *family, int flags, u8 cmd) |
515 | { | |
516 | struct nlmsghdr *nlh; | |
517 | struct genlmsghdr *hdr; | |
518 | ||
15e47304 | 519 | nlh = nlmsg_put(skb, portid, seq, family->id, GENL_HDRLEN + |
a46621a3 DV |
520 | family->hdrsize, flags); |
521 | if (nlh == NULL) | |
522 | return NULL; | |
523 | ||
524 | hdr = nlmsg_data(nlh); | |
525 | hdr->cmd = cmd; | |
526 | hdr->version = family->version; | |
527 | hdr->reserved = 0; | |
528 | ||
529 | return (char *) hdr + GENL_HDRLEN; | |
530 | } | |
531 | EXPORT_SYMBOL(genlmsg_put); | |
532 | ||
1d00a4eb | 533 | static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) |
482a8524 TG |
534 | { |
535 | struct genl_ops *ops; | |
536 | struct genl_family *family; | |
134e6375 | 537 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
538 | struct genl_info info; |
539 | struct genlmsghdr *hdr = nlmsg_data(nlh); | |
1d00a4eb | 540 | int hdrlen, err; |
482a8524 | 541 | |
746fac4d | 542 | family = genl_family_find_byid(nlh->nlmsg_type); |
1d00a4eb TG |
543 | if (family == NULL) |
544 | return -ENOENT; | |
482a8524 | 545 | |
134e6375 JB |
546 | /* this family doesn't exist in this netns */ |
547 | if (!family->netnsok && !net_eq(net, &init_net)) | |
548 | return -ENOENT; | |
549 | ||
482a8524 TG |
550 | hdrlen = GENL_HDRLEN + family->hdrsize; |
551 | if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) | |
1d00a4eb | 552 | return -EINVAL; |
482a8524 TG |
553 | |
554 | ops = genl_get_cmd(hdr->cmd, family); | |
1d00a4eb TG |
555 | if (ops == NULL) |
556 | return -EOPNOTSUPP; | |
482a8524 | 557 | |
1d00a4eb | 558 | if ((ops->flags & GENL_ADMIN_PERM) && |
fd778461 | 559 | !capable(CAP_NET_ADMIN)) |
1d00a4eb | 560 | return -EPERM; |
482a8524 | 561 | |
b8f3ab42 | 562 | if (nlh->nlmsg_flags & NLM_F_DUMP) { |
1d00a4eb TG |
563 | if (ops->dumpit == NULL) |
564 | return -EOPNOTSUPP; | |
482a8524 | 565 | |
6d1a3fb5 | 566 | genl_unlock(); |
80d326fa PNA |
567 | { |
568 | struct netlink_dump_control c = { | |
569 | .dump = ops->dumpit, | |
570 | .done = ops->done, | |
571 | }; | |
572 | err = netlink_dump_start(net->genl_sock, skb, nlh, &c); | |
573 | } | |
6d1a3fb5 PM |
574 | genl_lock(); |
575 | return err; | |
482a8524 TG |
576 | } |
577 | ||
1d00a4eb TG |
578 | if (ops->doit == NULL) |
579 | return -EOPNOTSUPP; | |
482a8524 TG |
580 | |
581 | if (family->attrbuf) { | |
582 | err = nlmsg_parse(nlh, hdrlen, family->attrbuf, family->maxattr, | |
583 | ops->policy); | |
584 | if (err < 0) | |
1d00a4eb | 585 | return err; |
482a8524 TG |
586 | } |
587 | ||
588 | info.snd_seq = nlh->nlmsg_seq; | |
15e47304 | 589 | info.snd_portid = NETLINK_CB(skb).portid; |
482a8524 TG |
590 | info.nlhdr = nlh; |
591 | info.genlhdr = nlmsg_data(nlh); | |
592 | info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN; | |
593 | info.attrs = family->attrbuf; | |
134e6375 | 594 | genl_info_net_set(&info, net); |
ff4c92d8 | 595 | memset(&info.user_ptr, 0, sizeof(info.user_ptr)); |
482a8524 | 596 | |
ff4c92d8 JB |
597 | if (family->pre_doit) { |
598 | err = family->pre_doit(ops, skb, &info); | |
599 | if (err) | |
600 | return err; | |
601 | } | |
602 | ||
603 | err = ops->doit(skb, &info); | |
604 | ||
605 | if (family->post_doit) | |
606 | family->post_doit(ops, skb, &info); | |
607 | ||
608 | return err; | |
482a8524 TG |
609 | } |
610 | ||
cd40b7d3 | 611 | static void genl_rcv(struct sk_buff *skb) |
482a8524 | 612 | { |
cd40b7d3 DL |
613 | genl_lock(); |
614 | netlink_rcv_skb(skb, &genl_rcv_msg); | |
615 | genl_unlock(); | |
482a8524 TG |
616 | } |
617 | ||
618 | /************************************************************************** | |
619 | * Controller | |
620 | **************************************************************************/ | |
621 | ||
17c157c8 TG |
622 | static struct genl_family genl_ctrl = { |
623 | .id = GENL_ID_CTRL, | |
624 | .name = "nlctrl", | |
334c29a6 | 625 | .version = 0x2, |
17c157c8 | 626 | .maxattr = CTRL_ATTR_MAX, |
134e6375 | 627 | .netnsok = true, |
17c157c8 TG |
628 | }; |
629 | ||
15e47304 | 630 | static int ctrl_fill_info(struct genl_family *family, u32 portid, u32 seq, |
482a8524 TG |
631 | u32 flags, struct sk_buff *skb, u8 cmd) |
632 | { | |
633 | void *hdr; | |
634 | ||
15e47304 | 635 | hdr = genlmsg_put(skb, portid, seq, &genl_ctrl, flags, cmd); |
482a8524 TG |
636 | if (hdr == NULL) |
637 | return -1; | |
638 | ||
444653f6 DM |
639 | if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, family->name) || |
640 | nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, family->id) || | |
641 | nla_put_u32(skb, CTRL_ATTR_VERSION, family->version) || | |
642 | nla_put_u32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize) || | |
643 | nla_put_u32(skb, CTRL_ATTR_MAXATTR, family->maxattr)) | |
644 | goto nla_put_failure; | |
eb328111 | 645 | |
e94ef682 TG |
646 | if (!list_empty(&family->ops_list)) { |
647 | struct nlattr *nla_ops; | |
648 | struct genl_ops *ops; | |
649 | int idx = 1; | |
eb328111 | 650 | |
e94ef682 TG |
651 | nla_ops = nla_nest_start(skb, CTRL_ATTR_OPS); |
652 | if (nla_ops == NULL) | |
eb328111 TG |
653 | goto nla_put_failure; |
654 | ||
e94ef682 TG |
655 | list_for_each_entry(ops, &family->ops_list, ops_list) { |
656 | struct nlattr *nest; | |
eb328111 | 657 | |
e94ef682 TG |
658 | nest = nla_nest_start(skb, idx++); |
659 | if (nest == NULL) | |
660 | goto nla_put_failure; | |
eb328111 | 661 | |
444653f6 DM |
662 | if (nla_put_u32(skb, CTRL_ATTR_OP_ID, ops->cmd) || |
663 | nla_put_u32(skb, CTRL_ATTR_OP_FLAGS, ops->flags)) | |
664 | goto nla_put_failure; | |
eb328111 | 665 | |
e94ef682 TG |
666 | nla_nest_end(skb, nest); |
667 | } | |
668 | ||
669 | nla_nest_end(skb, nla_ops); | |
670 | } | |
482a8524 | 671 | |
2dbba6f7 JB |
672 | if (!list_empty(&family->mcast_groups)) { |
673 | struct genl_multicast_group *grp; | |
674 | struct nlattr *nla_grps; | |
675 | int idx = 1; | |
676 | ||
677 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
678 | if (nla_grps == NULL) | |
679 | goto nla_put_failure; | |
680 | ||
681 | list_for_each_entry(grp, &family->mcast_groups, list) { | |
682 | struct nlattr *nest; | |
683 | ||
684 | nest = nla_nest_start(skb, idx++); | |
685 | if (nest == NULL) | |
686 | goto nla_put_failure; | |
687 | ||
444653f6 DM |
688 | if (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 | goto nla_put_failure; | |
2dbba6f7 JB |
692 | |
693 | nla_nest_end(skb, nest); | |
694 | } | |
695 | nla_nest_end(skb, nla_grps); | |
696 | } | |
697 | ||
698 | return genlmsg_end(skb, hdr); | |
699 | ||
700 | nla_put_failure: | |
bc3ed28c TG |
701 | genlmsg_cancel(skb, hdr); |
702 | return -EMSGSIZE; | |
2dbba6f7 JB |
703 | } |
704 | ||
15e47304 | 705 | static int ctrl_fill_mcgrp_info(struct genl_multicast_group *grp, u32 portid, |
2dbba6f7 JB |
706 | u32 seq, u32 flags, struct sk_buff *skb, |
707 | u8 cmd) | |
708 | { | |
709 | void *hdr; | |
710 | struct nlattr *nla_grps; | |
711 | struct nlattr *nest; | |
712 | ||
15e47304 | 713 | hdr = genlmsg_put(skb, portid, seq, &genl_ctrl, flags, cmd); |
2dbba6f7 JB |
714 | if (hdr == NULL) |
715 | return -1; | |
716 | ||
444653f6 DM |
717 | if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, grp->family->name) || |
718 | nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, grp->family->id)) | |
719 | goto nla_put_failure; | |
2dbba6f7 JB |
720 | |
721 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
722 | if (nla_grps == NULL) | |
723 | goto nla_put_failure; | |
724 | ||
725 | nest = nla_nest_start(skb, 1); | |
726 | if (nest == NULL) | |
727 | goto nla_put_failure; | |
728 | ||
444653f6 DM |
729 | if (nla_put_u32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id) || |
730 | nla_put_string(skb, CTRL_ATTR_MCAST_GRP_NAME, | |
731 | grp->name)) | |
732 | goto nla_put_failure; | |
2dbba6f7 JB |
733 | |
734 | nla_nest_end(skb, nest); | |
735 | nla_nest_end(skb, nla_grps); | |
736 | ||
482a8524 TG |
737 | return genlmsg_end(skb, hdr); |
738 | ||
739 | nla_put_failure: | |
bc3ed28c TG |
740 | genlmsg_cancel(skb, hdr); |
741 | return -EMSGSIZE; | |
482a8524 TG |
742 | } |
743 | ||
744 | static int ctrl_dumpfamily(struct sk_buff *skb, struct netlink_callback *cb) | |
745 | { | |
746 | ||
747 | int i, n = 0; | |
748 | struct genl_family *rt; | |
134e6375 | 749 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
750 | int chains_to_skip = cb->args[0]; |
751 | int fams_to_skip = cb->args[1]; | |
752 | ||
e1d5a010 | 753 | for (i = chains_to_skip; i < GENL_FAM_TAB_SIZE; i++) { |
482a8524 TG |
754 | n = 0; |
755 | list_for_each_entry(rt, genl_family_chain(i), family_list) { | |
134e6375 JB |
756 | if (!rt->netnsok && !net_eq(net, &init_net)) |
757 | continue; | |
482a8524 TG |
758 | if (++n < fams_to_skip) |
759 | continue; | |
15e47304 | 760 | if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).portid, |
482a8524 TG |
761 | cb->nlh->nlmsg_seq, NLM_F_MULTI, |
762 | skb, CTRL_CMD_NEWFAMILY) < 0) | |
763 | goto errout; | |
764 | } | |
765 | ||
766 | fams_to_skip = 0; | |
767 | } | |
768 | ||
769 | errout: | |
770 | cb->args[0] = i; | |
771 | cb->args[1] = n; | |
772 | ||
773 | return skb->len; | |
774 | } | |
775 | ||
2dbba6f7 | 776 | static struct sk_buff *ctrl_build_family_msg(struct genl_family *family, |
15e47304 | 777 | u32 portid, int seq, u8 cmd) |
482a8524 TG |
778 | { |
779 | struct sk_buff *skb; | |
780 | int err; | |
781 | ||
339bf98f | 782 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); |
482a8524 TG |
783 | if (skb == NULL) |
784 | return ERR_PTR(-ENOBUFS); | |
785 | ||
15e47304 | 786 | err = ctrl_fill_info(family, portid, seq, 0, skb, cmd); |
482a8524 TG |
787 | if (err < 0) { |
788 | nlmsg_free(skb); | |
789 | return ERR_PTR(err); | |
790 | } | |
791 | ||
792 | return skb; | |
793 | } | |
794 | ||
2dbba6f7 | 795 | static struct sk_buff *ctrl_build_mcgrp_msg(struct genl_multicast_group *grp, |
15e47304 | 796 | u32 portid, int seq, u8 cmd) |
2dbba6f7 JB |
797 | { |
798 | struct sk_buff *skb; | |
799 | int err; | |
800 | ||
801 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); | |
802 | if (skb == NULL) | |
803 | return ERR_PTR(-ENOBUFS); | |
804 | ||
15e47304 | 805 | err = ctrl_fill_mcgrp_info(grp, portid, seq, 0, skb, cmd); |
2dbba6f7 JB |
806 | if (err < 0) { |
807 | nlmsg_free(skb); | |
808 | return ERR_PTR(err); | |
809 | } | |
810 | ||
811 | return skb; | |
812 | } | |
813 | ||
ef7c79ed | 814 | static const struct nla_policy ctrl_policy[CTRL_ATTR_MAX+1] = { |
482a8524 | 815 | [CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 }, |
5176f91e TG |
816 | [CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING, |
817 | .len = GENL_NAMSIZ - 1 }, | |
482a8524 TG |
818 | }; |
819 | ||
820 | static int ctrl_getfamily(struct sk_buff *skb, struct genl_info *info) | |
821 | { | |
822 | struct sk_buff *msg; | |
823 | struct genl_family *res = NULL; | |
824 | int err = -EINVAL; | |
825 | ||
826 | if (info->attrs[CTRL_ATTR_FAMILY_ID]) { | |
827 | u16 id = nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]); | |
828 | res = genl_family_find_byid(id); | |
134e6375 | 829 | err = -ENOENT; |
482a8524 TG |
830 | } |
831 | ||
832 | if (info->attrs[CTRL_ATTR_FAMILY_NAME]) { | |
5176f91e | 833 | char *name; |
482a8524 | 834 | |
5176f91e | 835 | name = nla_data(info->attrs[CTRL_ATTR_FAMILY_NAME]); |
482a8524 | 836 | res = genl_family_find_byname(name); |
fa843095 SH |
837 | #ifdef CONFIG_MODULES |
838 | if (res == NULL) { | |
839 | genl_unlock(); | |
e9412c37 | 840 | request_module("net-pf-%d-proto-%d-family-%s", |
fa843095 SH |
841 | PF_NETLINK, NETLINK_GENERIC, name); |
842 | genl_lock(); | |
843 | res = genl_family_find_byname(name); | |
844 | } | |
845 | #endif | |
134e6375 | 846 | err = -ENOENT; |
482a8524 TG |
847 | } |
848 | ||
134e6375 JB |
849 | if (res == NULL) |
850 | return err; | |
851 | ||
852 | if (!res->netnsok && !net_eq(genl_info_net(info), &init_net)) { | |
853 | /* family doesn't exist here */ | |
854 | return -ENOENT; | |
482a8524 TG |
855 | } |
856 | ||
15e47304 | 857 | msg = ctrl_build_family_msg(res, info->snd_portid, info->snd_seq, |
2dbba6f7 | 858 | CTRL_CMD_NEWFAMILY); |
134e6375 JB |
859 | if (IS_ERR(msg)) |
860 | return PTR_ERR(msg); | |
482a8524 | 861 | |
134e6375 | 862 | return genlmsg_reply(msg, info); |
482a8524 TG |
863 | } |
864 | ||
865 | static int genl_ctrl_event(int event, void *data) | |
866 | { | |
867 | struct sk_buff *msg; | |
134e6375 JB |
868 | struct genl_family *family; |
869 | struct genl_multicast_group *grp; | |
482a8524 | 870 | |
134e6375 JB |
871 | /* genl is still initialising */ |
872 | if (!init_net.genl_sock) | |
482a8524 TG |
873 | return 0; |
874 | ||
875 | switch (event) { | |
876 | case CTRL_CMD_NEWFAMILY: | |
877 | case CTRL_CMD_DELFAMILY: | |
134e6375 JB |
878 | family = data; |
879 | msg = ctrl_build_family_msg(family, 0, 0, event); | |
2dbba6f7 JB |
880 | break; |
881 | case CTRL_CMD_NEWMCAST_GRP: | |
882 | case CTRL_CMD_DELMCAST_GRP: | |
134e6375 JB |
883 | grp = data; |
884 | family = grp->family; | |
2dbba6f7 | 885 | msg = ctrl_build_mcgrp_msg(data, 0, 0, event); |
482a8524 | 886 | break; |
134e6375 JB |
887 | default: |
888 | return -EINVAL; | |
889 | } | |
890 | ||
891 | if (IS_ERR(msg)) | |
892 | return PTR_ERR(msg); | |
893 | ||
894 | if (!family->netnsok) { | |
895 | genlmsg_multicast_netns(&init_net, msg, 0, | |
896 | GENL_ID_CTRL, GFP_KERNEL); | |
897 | } else { | |
898 | rcu_read_lock(); | |
899 | genlmsg_multicast_allns(msg, 0, GENL_ID_CTRL, GFP_ATOMIC); | |
900 | rcu_read_unlock(); | |
482a8524 TG |
901 | } |
902 | ||
903 | return 0; | |
904 | } | |
905 | ||
906 | static struct genl_ops genl_ctrl_ops = { | |
907 | .cmd = CTRL_CMD_GETFAMILY, | |
908 | .doit = ctrl_getfamily, | |
909 | .dumpit = ctrl_dumpfamily, | |
910 | .policy = ctrl_policy, | |
911 | }; | |
912 | ||
2dbba6f7 JB |
913 | static struct genl_multicast_group notify_grp = { |
914 | .name = "notify", | |
915 | }; | |
916 | ||
134e6375 JB |
917 | static int __net_init genl_pernet_init(struct net *net) |
918 | { | |
a31f2d17 PNA |
919 | struct netlink_kernel_cfg cfg = { |
920 | .input = genl_rcv, | |
921 | .cb_mutex = &genl_mutex, | |
9785e10a | 922 | .flags = NL_CFG_F_NONROOT_RECV, |
a31f2d17 PNA |
923 | }; |
924 | ||
134e6375 | 925 | /* we'll bump the group number right afterwards */ |
9f00d977 | 926 | net->genl_sock = netlink_kernel_create(net, NETLINK_GENERIC, &cfg); |
134e6375 JB |
927 | |
928 | if (!net->genl_sock && net_eq(net, &init_net)) | |
929 | panic("GENL: Cannot initialize generic netlink\n"); | |
930 | ||
931 | if (!net->genl_sock) | |
932 | return -ENOMEM; | |
933 | ||
934 | return 0; | |
935 | } | |
936 | ||
937 | static void __net_exit genl_pernet_exit(struct net *net) | |
938 | { | |
939 | netlink_kernel_release(net->genl_sock); | |
940 | net->genl_sock = NULL; | |
941 | } | |
942 | ||
943 | static struct pernet_operations genl_pernet_ops = { | |
944 | .init = genl_pernet_init, | |
945 | .exit = genl_pernet_exit, | |
946 | }; | |
947 | ||
482a8524 TG |
948 | static int __init genl_init(void) |
949 | { | |
950 | int i, err; | |
951 | ||
952 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) | |
953 | INIT_LIST_HEAD(&family_ht[i]); | |
954 | ||
652c6717 | 955 | err = genl_register_family_with_ops(&genl_ctrl, &genl_ctrl_ops, 1); |
482a8524 | 956 | if (err < 0) |
134e6375 | 957 | goto problem; |
482a8524 | 958 | |
134e6375 JB |
959 | err = register_pernet_subsys(&genl_pernet_ops); |
960 | if (err) | |
961 | goto problem; | |
482a8524 | 962 | |
2dbba6f7 JB |
963 | err = genl_register_mc_group(&genl_ctrl, ¬ify_grp); |
964 | if (err < 0) | |
134e6375 | 965 | goto problem; |
2dbba6f7 | 966 | |
482a8524 TG |
967 | return 0; |
968 | ||
134e6375 | 969 | problem: |
482a8524 | 970 | panic("GENL: Cannot register controller: %d\n", err); |
482a8524 TG |
971 | } |
972 | ||
973 | subsys_initcall(genl_init); | |
974 | ||
15e47304 | 975 | static int genlmsg_mcast(struct sk_buff *skb, u32 portid, unsigned long group, |
134e6375 JB |
976 | gfp_t flags) |
977 | { | |
978 | struct sk_buff *tmp; | |
979 | struct net *net, *prev = NULL; | |
980 | int err; | |
981 | ||
982 | for_each_net_rcu(net) { | |
983 | if (prev) { | |
984 | tmp = skb_clone(skb, flags); | |
985 | if (!tmp) { | |
986 | err = -ENOMEM; | |
987 | goto error; | |
988 | } | |
989 | err = nlmsg_multicast(prev->genl_sock, tmp, | |
15e47304 | 990 | portid, group, flags); |
134e6375 JB |
991 | if (err) |
992 | goto error; | |
993 | } | |
994 | ||
995 | prev = net; | |
996 | } | |
997 | ||
15e47304 | 998 | return nlmsg_multicast(prev->genl_sock, skb, portid, group, flags); |
134e6375 JB |
999 | error: |
1000 | kfree_skb(skb); | |
1001 | return err; | |
1002 | } | |
1003 | ||
15e47304 | 1004 | int genlmsg_multicast_allns(struct sk_buff *skb, u32 portid, unsigned int group, |
134e6375 JB |
1005 | gfp_t flags) |
1006 | { | |
15e47304 | 1007 | return genlmsg_mcast(skb, portid, group, flags); |
134e6375 JB |
1008 | } |
1009 | EXPORT_SYMBOL(genlmsg_multicast_allns); | |
263ba61d | 1010 | |
15e47304 | 1011 | void genl_notify(struct sk_buff *skb, struct net *net, u32 portid, u32 group, |
263ba61d PS |
1012 | struct nlmsghdr *nlh, gfp_t flags) |
1013 | { | |
1014 | struct sock *sk = net->genl_sock; | |
1015 | int report = 0; | |
1016 | ||
1017 | if (nlh) | |
1018 | report = nlmsg_report(nlh); | |
1019 | ||
15e47304 | 1020 | nlmsg_notify(sk, skb, portid, group, report, flags); |
263ba61d PS |
1021 | } |
1022 | EXPORT_SYMBOL(genl_notify); |