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 | ||
21 | struct sock *genl_sock = NULL; | |
22 | ||
14cc3e2b | 23 | static DEFINE_MUTEX(genl_mutex); /* serialization of message processing */ |
482a8524 TG |
24 | |
25 | static void genl_lock(void) | |
26 | { | |
14cc3e2b | 27 | mutex_lock(&genl_mutex); |
482a8524 TG |
28 | } |
29 | ||
30 | static int genl_trylock(void) | |
31 | { | |
14cc3e2b | 32 | return !mutex_trylock(&genl_mutex); |
482a8524 TG |
33 | } |
34 | ||
35 | static void genl_unlock(void) | |
36 | { | |
14cc3e2b | 37 | mutex_unlock(&genl_mutex); |
482a8524 TG |
38 | |
39 | if (genl_sock && genl_sock->sk_receive_queue.qlen) | |
40 | genl_sock->sk_data_ready(genl_sock, 0); | |
41 | } | |
42 | ||
43 | #define GENL_FAM_TAB_SIZE 16 | |
44 | #define GENL_FAM_TAB_MASK (GENL_FAM_TAB_SIZE - 1) | |
45 | ||
46 | static struct list_head family_ht[GENL_FAM_TAB_SIZE]; | |
2dbba6f7 JB |
47 | /* |
48 | * Bitmap of multicast groups that are currently in use. | |
49 | * | |
50 | * To avoid an allocation at boot of just one unsigned long, | |
51 | * declare it global instead. | |
52 | * Bit 0 is marked as already used since group 0 is invalid. | |
53 | */ | |
54 | static unsigned long mc_group_start = 0x1; | |
55 | static unsigned long *mc_groups = &mc_group_start; | |
56 | static unsigned long mc_groups_longs = 1; | |
482a8524 TG |
57 | |
58 | static int genl_ctrl_event(int event, void *data); | |
59 | ||
60 | static inline unsigned int genl_family_hash(unsigned int id) | |
61 | { | |
62 | return id & GENL_FAM_TAB_MASK; | |
63 | } | |
64 | ||
65 | static inline struct list_head *genl_family_chain(unsigned int id) | |
66 | { | |
67 | return &family_ht[genl_family_hash(id)]; | |
68 | } | |
69 | ||
70 | static struct genl_family *genl_family_find_byid(unsigned int id) | |
71 | { | |
72 | struct genl_family *f; | |
73 | ||
74 | list_for_each_entry(f, genl_family_chain(id), family_list) | |
75 | if (f->id == id) | |
76 | return f; | |
77 | ||
78 | return NULL; | |
79 | } | |
80 | ||
81 | static struct genl_family *genl_family_find_byname(char *name) | |
82 | { | |
83 | struct genl_family *f; | |
84 | int i; | |
85 | ||
86 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) | |
87 | list_for_each_entry(f, genl_family_chain(i), family_list) | |
88 | if (strcmp(f->name, name) == 0) | |
89 | return f; | |
90 | ||
91 | return NULL; | |
92 | } | |
93 | ||
94 | static struct genl_ops *genl_get_cmd(u8 cmd, struct genl_family *family) | |
95 | { | |
96 | struct genl_ops *ops; | |
97 | ||
98 | list_for_each_entry(ops, &family->ops_list, ops_list) | |
99 | if (ops->cmd == cmd) | |
100 | return ops; | |
101 | ||
102 | return NULL; | |
103 | } | |
104 | ||
105 | /* Of course we are going to have problems once we hit | |
106 | * 2^16 alive types, but that can only happen by year 2K | |
107 | */ | |
108 | static inline u16 genl_generate_id(void) | |
109 | { | |
110 | static u16 id_gen_idx; | |
111 | int overflowed = 0; | |
112 | ||
113 | do { | |
114 | if (id_gen_idx == 0) | |
115 | id_gen_idx = GENL_MIN_ID; | |
116 | ||
117 | if (++id_gen_idx > GENL_MAX_ID) { | |
118 | if (!overflowed) { | |
119 | overflowed = 1; | |
120 | id_gen_idx = 0; | |
121 | continue; | |
122 | } else | |
123 | return 0; | |
124 | } | |
125 | ||
126 | } while (genl_family_find_byid(id_gen_idx)); | |
127 | ||
128 | return id_gen_idx; | |
129 | } | |
130 | ||
2dbba6f7 JB |
131 | static struct genl_multicast_group notify_grp; |
132 | ||
133 | /** | |
134 | * genl_register_mc_group - register a multicast group | |
135 | * | |
136 | * Registers the specified multicast group and notifies userspace | |
137 | * about the new group. | |
138 | * | |
139 | * Returns 0 on success or a negative error code. | |
140 | * | |
141 | * @family: The generic netlink family the group shall be registered for. | |
142 | * @grp: The group to register, must have a name. | |
143 | */ | |
144 | int genl_register_mc_group(struct genl_family *family, | |
145 | struct genl_multicast_group *grp) | |
146 | { | |
147 | int id; | |
148 | unsigned long *new_groups; | |
149 | int err; | |
150 | ||
151 | BUG_ON(grp->name[0] == '\0'); | |
152 | ||
153 | genl_lock(); | |
154 | ||
155 | /* special-case our own group */ | |
156 | if (grp == ¬ify_grp) | |
157 | id = GENL_ID_CTRL; | |
158 | else | |
159 | id = find_first_zero_bit(mc_groups, | |
160 | mc_groups_longs * BITS_PER_LONG); | |
161 | ||
162 | ||
163 | if (id >= mc_groups_longs * BITS_PER_LONG) { | |
164 | size_t nlen = (mc_groups_longs + 1) * sizeof(unsigned long); | |
165 | ||
166 | if (mc_groups == &mc_group_start) { | |
167 | new_groups = kzalloc(nlen, GFP_KERNEL); | |
168 | if (!new_groups) { | |
169 | err = -ENOMEM; | |
170 | goto out; | |
171 | } | |
172 | mc_groups = new_groups; | |
173 | *mc_groups = mc_group_start; | |
174 | } else { | |
175 | new_groups = krealloc(mc_groups, nlen, GFP_KERNEL); | |
176 | if (!new_groups) { | |
177 | err = -ENOMEM; | |
178 | goto out; | |
179 | } | |
180 | mc_groups = new_groups; | |
181 | mc_groups[mc_groups_longs] = 0; | |
182 | } | |
183 | mc_groups_longs++; | |
184 | } | |
185 | ||
186 | err = netlink_change_ngroups(genl_sock, | |
2c04ddb7 | 187 | mc_groups_longs * BITS_PER_LONG); |
2dbba6f7 JB |
188 | if (err) |
189 | goto out; | |
190 | ||
191 | grp->id = id; | |
192 | set_bit(id, mc_groups); | |
193 | list_add_tail(&grp->list, &family->mcast_groups); | |
194 | grp->family = family; | |
195 | ||
196 | genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, grp); | |
197 | out: | |
198 | genl_unlock(); | |
79d310d0 | 199 | return err; |
2dbba6f7 JB |
200 | } |
201 | EXPORT_SYMBOL(genl_register_mc_group); | |
202 | ||
79dc4386 TG |
203 | static void __genl_unregister_mc_group(struct genl_family *family, |
204 | struct genl_multicast_group *grp) | |
205 | { | |
206 | BUG_ON(grp->family != family); | |
207 | netlink_clear_multicast_users(genl_sock, grp->id); | |
208 | clear_bit(grp->id, mc_groups); | |
209 | list_del(&grp->list); | |
210 | genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, grp); | |
211 | grp->id = 0; | |
212 | grp->family = NULL; | |
213 | } | |
214 | ||
2dbba6f7 JB |
215 | /** |
216 | * genl_unregister_mc_group - unregister a multicast group | |
217 | * | |
218 | * Unregisters the specified multicast group and notifies userspace | |
219 | * about it. All current listeners on the group are removed. | |
220 | * | |
221 | * Note: It is not necessary to unregister all multicast groups before | |
222 | * unregistering the family, unregistering the family will cause | |
223 | * all assigned multicast groups to be unregistered automatically. | |
224 | * | |
225 | * @family: Generic netlink family the group belongs to. | |
226 | * @grp: The group to unregister, must have been registered successfully | |
227 | * previously. | |
228 | */ | |
229 | void genl_unregister_mc_group(struct genl_family *family, | |
230 | struct genl_multicast_group *grp) | |
231 | { | |
2dbba6f7 | 232 | genl_lock(); |
79dc4386 | 233 | __genl_unregister_mc_group(family, grp); |
2dbba6f7 JB |
234 | genl_unlock(); |
235 | } | |
236 | ||
237 | static void genl_unregister_mc_groups(struct genl_family *family) | |
238 | { | |
239 | struct genl_multicast_group *grp, *tmp; | |
240 | ||
79dc4386 | 241 | genl_lock(); |
2dbba6f7 | 242 | list_for_each_entry_safe(grp, tmp, &family->mcast_groups, list) |
79dc4386 TG |
243 | __genl_unregister_mc_group(family, grp); |
244 | genl_unlock(); | |
2dbba6f7 JB |
245 | } |
246 | ||
482a8524 TG |
247 | /** |
248 | * genl_register_ops - register generic netlink operations | |
249 | * @family: generic netlink family | |
250 | * @ops: operations to be registered | |
251 | * | |
252 | * Registers the specified operations and assigns them to the specified | |
253 | * family. Either a doit or dumpit callback must be specified or the | |
254 | * operation will fail. Only one operation structure per command | |
255 | * identifier may be registered. | |
256 | * | |
257 | * See include/net/genetlink.h for more documenation on the operations | |
258 | * structure. | |
259 | * | |
260 | * Returns 0 on success or a negative error code. | |
261 | */ | |
262 | int genl_register_ops(struct genl_family *family, struct genl_ops *ops) | |
263 | { | |
264 | int err = -EINVAL; | |
265 | ||
266 | if (ops->dumpit == NULL && ops->doit == NULL) | |
267 | goto errout; | |
268 | ||
269 | if (genl_get_cmd(ops->cmd, family)) { | |
270 | err = -EEXIST; | |
271 | goto errout; | |
272 | } | |
273 | ||
334c29a6 | 274 | if (ops->dumpit) |
334c29a6 | 275 | ops->flags |= GENL_CMD_CAP_DUMP; |
48d4ed7a JHS |
276 | if (ops->doit) |
277 | ops->flags |= GENL_CMD_CAP_DO; | |
334c29a6 JHS |
278 | if (ops->policy) |
279 | ops->flags |= GENL_CMD_CAP_HASPOL; | |
280 | ||
482a8524 TG |
281 | genl_lock(); |
282 | list_add_tail(&ops->ops_list, &family->ops_list); | |
283 | genl_unlock(); | |
284 | ||
285 | genl_ctrl_event(CTRL_CMD_NEWOPS, ops); | |
286 | err = 0; | |
287 | errout: | |
288 | return err; | |
289 | } | |
290 | ||
291 | /** | |
292 | * genl_unregister_ops - unregister generic netlink operations | |
293 | * @family: generic netlink family | |
294 | * @ops: operations to be unregistered | |
295 | * | |
296 | * Unregisters the specified operations and unassigns them from the | |
297 | * specified family. The operation blocks until the current message | |
298 | * processing has finished and doesn't start again until the | |
299 | * unregister process has finished. | |
300 | * | |
301 | * Note: It is not necessary to unregister all operations before | |
302 | * unregistering the family, unregistering the family will cause | |
303 | * all assigned operations to be unregistered automatically. | |
304 | * | |
305 | * Returns 0 on success or a negative error code. | |
306 | */ | |
307 | int genl_unregister_ops(struct genl_family *family, struct genl_ops *ops) | |
308 | { | |
309 | struct genl_ops *rc; | |
310 | ||
311 | genl_lock(); | |
312 | list_for_each_entry(rc, &family->ops_list, ops_list) { | |
313 | if (rc == ops) { | |
314 | list_del(&ops->ops_list); | |
315 | genl_unlock(); | |
316 | genl_ctrl_event(CTRL_CMD_DELOPS, ops); | |
317 | return 0; | |
318 | } | |
319 | } | |
320 | genl_unlock(); | |
321 | ||
322 | return -ENOENT; | |
323 | } | |
324 | ||
325 | /** | |
326 | * genl_register_family - register a generic netlink family | |
327 | * @family: generic netlink family | |
328 | * | |
329 | * Registers the specified family after validating it first. Only one | |
330 | * family may be registered with the same family name or identifier. | |
331 | * The family id may equal GENL_ID_GENERATE causing an unique id to | |
332 | * be automatically generated and assigned. | |
333 | * | |
334 | * Return 0 on success or a negative error code. | |
335 | */ | |
336 | int genl_register_family(struct genl_family *family) | |
337 | { | |
338 | int err = -EINVAL; | |
339 | ||
340 | if (family->id && family->id < GENL_MIN_ID) | |
341 | goto errout; | |
342 | ||
343 | if (family->id > GENL_MAX_ID) | |
344 | goto errout; | |
345 | ||
346 | INIT_LIST_HEAD(&family->ops_list); | |
2dbba6f7 | 347 | INIT_LIST_HEAD(&family->mcast_groups); |
482a8524 TG |
348 | |
349 | genl_lock(); | |
350 | ||
351 | if (genl_family_find_byname(family->name)) { | |
352 | err = -EEXIST; | |
353 | goto errout_locked; | |
354 | } | |
355 | ||
356 | if (genl_family_find_byid(family->id)) { | |
357 | err = -EEXIST; | |
358 | goto errout_locked; | |
359 | } | |
360 | ||
482a8524 TG |
361 | if (family->id == GENL_ID_GENERATE) { |
362 | u16 newid = genl_generate_id(); | |
363 | ||
364 | if (!newid) { | |
365 | err = -ENOMEM; | |
366 | goto errout_locked; | |
367 | } | |
368 | ||
369 | family->id = newid; | |
370 | } | |
371 | ||
372 | if (family->maxattr) { | |
373 | family->attrbuf = kmalloc((family->maxattr+1) * | |
374 | sizeof(struct nlattr *), GFP_KERNEL); | |
375 | if (family->attrbuf == NULL) { | |
376 | err = -ENOMEM; | |
e200bd80 | 377 | goto errout_locked; |
482a8524 TG |
378 | } |
379 | } else | |
380 | family->attrbuf = NULL; | |
381 | ||
382 | list_add_tail(&family->family_list, genl_family_chain(family->id)); | |
383 | genl_unlock(); | |
384 | ||
385 | genl_ctrl_event(CTRL_CMD_NEWFAMILY, family); | |
386 | ||
387 | return 0; | |
388 | ||
389 | errout_locked: | |
390 | genl_unlock(); | |
391 | errout: | |
392 | return err; | |
393 | } | |
394 | ||
395 | /** | |
396 | * genl_unregister_family - unregister generic netlink family | |
397 | * @family: generic netlink family | |
398 | * | |
399 | * Unregisters the specified family. | |
400 | * | |
401 | * Returns 0 on success or a negative error code. | |
402 | */ | |
403 | int genl_unregister_family(struct genl_family *family) | |
404 | { | |
405 | struct genl_family *rc; | |
406 | ||
2dbba6f7 JB |
407 | genl_unregister_mc_groups(family); |
408 | ||
482a8524 TG |
409 | genl_lock(); |
410 | ||
411 | list_for_each_entry(rc, genl_family_chain(family->id), family_list) { | |
412 | if (family->id != rc->id || strcmp(rc->name, family->name)) | |
413 | continue; | |
414 | ||
415 | list_del(&rc->family_list); | |
416 | INIT_LIST_HEAD(&family->ops_list); | |
417 | genl_unlock(); | |
418 | ||
482a8524 TG |
419 | kfree(family->attrbuf); |
420 | genl_ctrl_event(CTRL_CMD_DELFAMILY, family); | |
421 | return 0; | |
422 | } | |
423 | ||
424 | genl_unlock(); | |
425 | ||
426 | return -ENOENT; | |
427 | } | |
428 | ||
1d00a4eb | 429 | static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) |
482a8524 TG |
430 | { |
431 | struct genl_ops *ops; | |
432 | struct genl_family *family; | |
433 | struct genl_info info; | |
434 | struct genlmsghdr *hdr = nlmsg_data(nlh); | |
1d00a4eb | 435 | int hdrlen, err; |
482a8524 | 436 | |
746fac4d | 437 | family = genl_family_find_byid(nlh->nlmsg_type); |
1d00a4eb TG |
438 | if (family == NULL) |
439 | return -ENOENT; | |
482a8524 TG |
440 | |
441 | hdrlen = GENL_HDRLEN + family->hdrsize; | |
442 | if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) | |
1d00a4eb | 443 | return -EINVAL; |
482a8524 TG |
444 | |
445 | ops = genl_get_cmd(hdr->cmd, family); | |
1d00a4eb TG |
446 | if (ops == NULL) |
447 | return -EOPNOTSUPP; | |
482a8524 | 448 | |
1d00a4eb TG |
449 | if ((ops->flags & GENL_ADMIN_PERM) && |
450 | security_netlink_recv(skb, CAP_NET_ADMIN)) | |
451 | return -EPERM; | |
482a8524 TG |
452 | |
453 | if (nlh->nlmsg_flags & NLM_F_DUMP) { | |
1d00a4eb TG |
454 | if (ops->dumpit == NULL) |
455 | return -EOPNOTSUPP; | |
482a8524 | 456 | |
c702e804 TG |
457 | return netlink_dump_start(genl_sock, skb, nlh, |
458 | ops->dumpit, ops->done); | |
482a8524 TG |
459 | } |
460 | ||
1d00a4eb TG |
461 | if (ops->doit == NULL) |
462 | return -EOPNOTSUPP; | |
482a8524 TG |
463 | |
464 | if (family->attrbuf) { | |
465 | err = nlmsg_parse(nlh, hdrlen, family->attrbuf, family->maxattr, | |
466 | ops->policy); | |
467 | if (err < 0) | |
1d00a4eb | 468 | return err; |
482a8524 TG |
469 | } |
470 | ||
471 | info.snd_seq = nlh->nlmsg_seq; | |
472 | info.snd_pid = NETLINK_CB(skb).pid; | |
473 | info.nlhdr = nlh; | |
474 | info.genlhdr = nlmsg_data(nlh); | |
475 | info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN; | |
476 | info.attrs = family->attrbuf; | |
477 | ||
1d00a4eb | 478 | return ops->doit(skb, &info); |
482a8524 TG |
479 | } |
480 | ||
481 | static void genl_rcv(struct sock *sk, int len) | |
482 | { | |
483 | unsigned int qlen = 0; | |
484 | ||
485 | do { | |
486 | if (genl_trylock()) | |
487 | return; | |
0cfad075 | 488 | qlen = netlink_run_queue(sk, qlen, genl_rcv_msg); |
482a8524 TG |
489 | genl_unlock(); |
490 | } while (qlen && genl_sock && genl_sock->sk_receive_queue.qlen); | |
491 | } | |
492 | ||
493 | /************************************************************************** | |
494 | * Controller | |
495 | **************************************************************************/ | |
496 | ||
17c157c8 TG |
497 | static struct genl_family genl_ctrl = { |
498 | .id = GENL_ID_CTRL, | |
499 | .name = "nlctrl", | |
334c29a6 | 500 | .version = 0x2, |
17c157c8 TG |
501 | .maxattr = CTRL_ATTR_MAX, |
502 | }; | |
503 | ||
482a8524 TG |
504 | static int ctrl_fill_info(struct genl_family *family, u32 pid, u32 seq, |
505 | u32 flags, struct sk_buff *skb, u8 cmd) | |
506 | { | |
507 | void *hdr; | |
508 | ||
17c157c8 | 509 | hdr = genlmsg_put(skb, pid, seq, &genl_ctrl, flags, cmd); |
482a8524 TG |
510 | if (hdr == NULL) |
511 | return -1; | |
512 | ||
513 | NLA_PUT_STRING(skb, CTRL_ATTR_FAMILY_NAME, family->name); | |
514 | NLA_PUT_U16(skb, CTRL_ATTR_FAMILY_ID, family->id); | |
eb328111 TG |
515 | NLA_PUT_U32(skb, CTRL_ATTR_VERSION, family->version); |
516 | NLA_PUT_U32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize); | |
517 | NLA_PUT_U32(skb, CTRL_ATTR_MAXATTR, family->maxattr); | |
518 | ||
e94ef682 TG |
519 | if (!list_empty(&family->ops_list)) { |
520 | struct nlattr *nla_ops; | |
521 | struct genl_ops *ops; | |
522 | int idx = 1; | |
eb328111 | 523 | |
e94ef682 TG |
524 | nla_ops = nla_nest_start(skb, CTRL_ATTR_OPS); |
525 | if (nla_ops == NULL) | |
eb328111 TG |
526 | goto nla_put_failure; |
527 | ||
e94ef682 TG |
528 | list_for_each_entry(ops, &family->ops_list, ops_list) { |
529 | struct nlattr *nest; | |
eb328111 | 530 | |
e94ef682 TG |
531 | nest = nla_nest_start(skb, idx++); |
532 | if (nest == NULL) | |
533 | goto nla_put_failure; | |
eb328111 | 534 | |
e94ef682 TG |
535 | NLA_PUT_U32(skb, CTRL_ATTR_OP_ID, ops->cmd); |
536 | NLA_PUT_U32(skb, CTRL_ATTR_OP_FLAGS, ops->flags); | |
eb328111 | 537 | |
e94ef682 TG |
538 | nla_nest_end(skb, nest); |
539 | } | |
540 | ||
541 | nla_nest_end(skb, nla_ops); | |
542 | } | |
482a8524 | 543 | |
2dbba6f7 JB |
544 | if (!list_empty(&family->mcast_groups)) { |
545 | struct genl_multicast_group *grp; | |
546 | struct nlattr *nla_grps; | |
547 | int idx = 1; | |
548 | ||
549 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
550 | if (nla_grps == NULL) | |
551 | goto nla_put_failure; | |
552 | ||
553 | list_for_each_entry(grp, &family->mcast_groups, list) { | |
554 | struct nlattr *nest; | |
555 | ||
556 | nest = nla_nest_start(skb, idx++); | |
557 | if (nest == NULL) | |
558 | goto nla_put_failure; | |
559 | ||
560 | NLA_PUT_U32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id); | |
561 | NLA_PUT_STRING(skb, CTRL_ATTR_MCAST_GRP_NAME, | |
562 | grp->name); | |
563 | ||
564 | nla_nest_end(skb, nest); | |
565 | } | |
566 | nla_nest_end(skb, nla_grps); | |
567 | } | |
568 | ||
569 | return genlmsg_end(skb, hdr); | |
570 | ||
571 | nla_put_failure: | |
572 | return genlmsg_cancel(skb, hdr); | |
573 | } | |
574 | ||
575 | static int ctrl_fill_mcgrp_info(struct genl_multicast_group *grp, u32 pid, | |
576 | u32 seq, u32 flags, struct sk_buff *skb, | |
577 | u8 cmd) | |
578 | { | |
579 | void *hdr; | |
580 | struct nlattr *nla_grps; | |
581 | struct nlattr *nest; | |
582 | ||
583 | hdr = genlmsg_put(skb, pid, seq, &genl_ctrl, flags, cmd); | |
584 | if (hdr == NULL) | |
585 | return -1; | |
586 | ||
587 | NLA_PUT_STRING(skb, CTRL_ATTR_FAMILY_NAME, grp->family->name); | |
588 | NLA_PUT_U16(skb, CTRL_ATTR_FAMILY_ID, grp->family->id); | |
589 | ||
590 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
591 | if (nla_grps == NULL) | |
592 | goto nla_put_failure; | |
593 | ||
594 | nest = nla_nest_start(skb, 1); | |
595 | if (nest == NULL) | |
596 | goto nla_put_failure; | |
597 | ||
598 | NLA_PUT_U32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id); | |
599 | NLA_PUT_STRING(skb, CTRL_ATTR_MCAST_GRP_NAME, | |
600 | grp->name); | |
601 | ||
602 | nla_nest_end(skb, nest); | |
603 | nla_nest_end(skb, nla_grps); | |
604 | ||
482a8524 TG |
605 | return genlmsg_end(skb, hdr); |
606 | ||
607 | nla_put_failure: | |
608 | return genlmsg_cancel(skb, hdr); | |
609 | } | |
610 | ||
611 | static int ctrl_dumpfamily(struct sk_buff *skb, struct netlink_callback *cb) | |
612 | { | |
613 | ||
614 | int i, n = 0; | |
615 | struct genl_family *rt; | |
616 | int chains_to_skip = cb->args[0]; | |
617 | int fams_to_skip = cb->args[1]; | |
618 | ||
eb328111 TG |
619 | if (chains_to_skip != 0) |
620 | genl_lock(); | |
621 | ||
482a8524 TG |
622 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) { |
623 | if (i < chains_to_skip) | |
624 | continue; | |
625 | n = 0; | |
626 | list_for_each_entry(rt, genl_family_chain(i), family_list) { | |
627 | if (++n < fams_to_skip) | |
628 | continue; | |
629 | if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).pid, | |
630 | cb->nlh->nlmsg_seq, NLM_F_MULTI, | |
631 | skb, CTRL_CMD_NEWFAMILY) < 0) | |
632 | goto errout; | |
633 | } | |
634 | ||
635 | fams_to_skip = 0; | |
636 | } | |
637 | ||
638 | errout: | |
eb328111 TG |
639 | if (chains_to_skip != 0) |
640 | genl_unlock(); | |
641 | ||
482a8524 TG |
642 | cb->args[0] = i; |
643 | cb->args[1] = n; | |
644 | ||
645 | return skb->len; | |
646 | } | |
647 | ||
2dbba6f7 JB |
648 | static struct sk_buff *ctrl_build_family_msg(struct genl_family *family, |
649 | u32 pid, int seq, u8 cmd) | |
482a8524 TG |
650 | { |
651 | struct sk_buff *skb; | |
652 | int err; | |
653 | ||
339bf98f | 654 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); |
482a8524 TG |
655 | if (skb == NULL) |
656 | return ERR_PTR(-ENOBUFS); | |
657 | ||
658 | err = ctrl_fill_info(family, pid, seq, 0, skb, cmd); | |
659 | if (err < 0) { | |
660 | nlmsg_free(skb); | |
661 | return ERR_PTR(err); | |
662 | } | |
663 | ||
664 | return skb; | |
665 | } | |
666 | ||
2dbba6f7 JB |
667 | static struct sk_buff *ctrl_build_mcgrp_msg(struct genl_multicast_group *grp, |
668 | u32 pid, int seq, u8 cmd) | |
669 | { | |
670 | struct sk_buff *skb; | |
671 | int err; | |
672 | ||
673 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); | |
674 | if (skb == NULL) | |
675 | return ERR_PTR(-ENOBUFS); | |
676 | ||
677 | err = ctrl_fill_mcgrp_info(grp, pid, seq, 0, skb, cmd); | |
678 | if (err < 0) { | |
679 | nlmsg_free(skb); | |
680 | return ERR_PTR(err); | |
681 | } | |
682 | ||
683 | return skb; | |
684 | } | |
685 | ||
ef7c79ed | 686 | static const struct nla_policy ctrl_policy[CTRL_ATTR_MAX+1] = { |
482a8524 | 687 | [CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 }, |
5176f91e TG |
688 | [CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING, |
689 | .len = GENL_NAMSIZ - 1 }, | |
482a8524 TG |
690 | }; |
691 | ||
692 | static int ctrl_getfamily(struct sk_buff *skb, struct genl_info *info) | |
693 | { | |
694 | struct sk_buff *msg; | |
695 | struct genl_family *res = NULL; | |
696 | int err = -EINVAL; | |
697 | ||
698 | if (info->attrs[CTRL_ATTR_FAMILY_ID]) { | |
699 | u16 id = nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]); | |
700 | res = genl_family_find_byid(id); | |
701 | } | |
702 | ||
703 | if (info->attrs[CTRL_ATTR_FAMILY_NAME]) { | |
5176f91e | 704 | char *name; |
482a8524 | 705 | |
5176f91e | 706 | name = nla_data(info->attrs[CTRL_ATTR_FAMILY_NAME]); |
482a8524 TG |
707 | res = genl_family_find_byname(name); |
708 | } | |
709 | ||
710 | if (res == NULL) { | |
711 | err = -ENOENT; | |
712 | goto errout; | |
713 | } | |
714 | ||
2dbba6f7 JB |
715 | msg = ctrl_build_family_msg(res, info->snd_pid, info->snd_seq, |
716 | CTRL_CMD_NEWFAMILY); | |
482a8524 TG |
717 | if (IS_ERR(msg)) { |
718 | err = PTR_ERR(msg); | |
719 | goto errout; | |
720 | } | |
721 | ||
81878d27 | 722 | err = genlmsg_reply(msg, info); |
482a8524 TG |
723 | errout: |
724 | return err; | |
725 | } | |
726 | ||
727 | static int genl_ctrl_event(int event, void *data) | |
728 | { | |
729 | struct sk_buff *msg; | |
730 | ||
731 | if (genl_sock == NULL) | |
732 | return 0; | |
733 | ||
734 | switch (event) { | |
735 | case CTRL_CMD_NEWFAMILY: | |
736 | case CTRL_CMD_DELFAMILY: | |
2dbba6f7 JB |
737 | msg = ctrl_build_family_msg(data, 0, 0, event); |
738 | if (IS_ERR(msg)) | |
739 | return PTR_ERR(msg); | |
740 | ||
741 | genlmsg_multicast(msg, 0, GENL_ID_CTRL, GFP_KERNEL); | |
742 | break; | |
743 | case CTRL_CMD_NEWMCAST_GRP: | |
744 | case CTRL_CMD_DELMCAST_GRP: | |
745 | msg = ctrl_build_mcgrp_msg(data, 0, 0, event); | |
482a8524 TG |
746 | if (IS_ERR(msg)) |
747 | return PTR_ERR(msg); | |
748 | ||
d387f6ad | 749 | genlmsg_multicast(msg, 0, GENL_ID_CTRL, GFP_KERNEL); |
482a8524 TG |
750 | break; |
751 | } | |
752 | ||
753 | return 0; | |
754 | } | |
755 | ||
756 | static struct genl_ops genl_ctrl_ops = { | |
757 | .cmd = CTRL_CMD_GETFAMILY, | |
758 | .doit = ctrl_getfamily, | |
759 | .dumpit = ctrl_dumpfamily, | |
760 | .policy = ctrl_policy, | |
761 | }; | |
762 | ||
2dbba6f7 JB |
763 | static struct genl_multicast_group notify_grp = { |
764 | .name = "notify", | |
765 | }; | |
766 | ||
482a8524 TG |
767 | static int __init genl_init(void) |
768 | { | |
769 | int i, err; | |
770 | ||
771 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) | |
772 | INIT_LIST_HEAD(&family_ht[i]); | |
773 | ||
774 | err = genl_register_family(&genl_ctrl); | |
775 | if (err < 0) | |
776 | goto errout; | |
777 | ||
778 | err = genl_register_ops(&genl_ctrl, &genl_ctrl_ops); | |
779 | if (err < 0) | |
780 | goto errout_register; | |
781 | ||
782 | netlink_set_nonroot(NETLINK_GENERIC, NL_NONROOT_RECV); | |
2dbba6f7 JB |
783 | |
784 | /* we'll bump the group number right afterwards */ | |
b4b51029 EB |
785 | genl_sock = netlink_kernel_create(&init_net, NETLINK_GENERIC, 0, |
786 | genl_rcv, NULL, THIS_MODULE); | |
e200bd80 | 787 | if (genl_sock == NULL) |
482a8524 | 788 | panic("GENL: Cannot initialize generic netlink\n"); |
482a8524 | 789 | |
2dbba6f7 JB |
790 | err = genl_register_mc_group(&genl_ctrl, ¬ify_grp); |
791 | if (err < 0) | |
792 | goto errout_register; | |
793 | ||
482a8524 TG |
794 | return 0; |
795 | ||
796 | errout_register: | |
797 | genl_unregister_family(&genl_ctrl); | |
798 | errout: | |
799 | panic("GENL: Cannot register controller: %d\n", err); | |
482a8524 TG |
800 | } |
801 | ||
802 | subsys_initcall(genl_init); | |
803 | ||
804 | EXPORT_SYMBOL(genl_sock); | |
805 | EXPORT_SYMBOL(genl_register_ops); | |
806 | EXPORT_SYMBOL(genl_unregister_ops); | |
807 | EXPORT_SYMBOL(genl_register_family); | |
808 | EXPORT_SYMBOL(genl_unregister_family); |