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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
482a8524 TG |
2 | /* |
3 | * NETLINK Generic Netlink Family | |
4 | * | |
5 | * Authors: Jamal Hadi Salim | |
6 | * Thomas Graf <tgraf@suug.ch> | |
2dbba6f7 | 7 | * Johannes Berg <johannes@sipsolutions.net> |
482a8524 TG |
8 | */ |
9 | ||
482a8524 TG |
10 | #include <linux/module.h> |
11 | #include <linux/kernel.h> | |
5a0e3ad6 | 12 | #include <linux/slab.h> |
482a8524 TG |
13 | #include <linux/errno.h> |
14 | #include <linux/types.h> | |
15 | #include <linux/socket.h> | |
16 | #include <linux/string.h> | |
17 | #include <linux/skbuff.h> | |
14cc3e2b | 18 | #include <linux/mutex.h> |
2dbba6f7 | 19 | #include <linux/bitmap.h> |
def31174 | 20 | #include <linux/rwsem.h> |
2ae0f17d | 21 | #include <linux/idr.h> |
482a8524 TG |
22 | #include <net/sock.h> |
23 | #include <net/genetlink.h> | |
24 | ||
14cc3e2b | 25 | static DEFINE_MUTEX(genl_mutex); /* serialization of message processing */ |
def31174 | 26 | static DECLARE_RWSEM(cb_lock); |
482a8524 | 27 | |
ee1c2442 JB |
28 | atomic_t genl_sk_destructing_cnt = ATOMIC_INIT(0); |
29 | DECLARE_WAIT_QUEUE_HEAD(genl_sk_destructing_waitq); | |
30 | ||
f408e0ce | 31 | void genl_lock(void) |
482a8524 | 32 | { |
14cc3e2b | 33 | mutex_lock(&genl_mutex); |
482a8524 | 34 | } |
f408e0ce | 35 | EXPORT_SYMBOL(genl_lock); |
482a8524 | 36 | |
f408e0ce | 37 | void genl_unlock(void) |
482a8524 | 38 | { |
14cc3e2b | 39 | mutex_unlock(&genl_mutex); |
482a8524 | 40 | } |
f408e0ce | 41 | EXPORT_SYMBOL(genl_unlock); |
482a8524 | 42 | |
320f5ea0 | 43 | #ifdef CONFIG_LOCKDEP |
61d03535 | 44 | bool lockdep_genl_is_held(void) |
86b1309c PS |
45 | { |
46 | return lockdep_is_held(&genl_mutex); | |
47 | } | |
48 | EXPORT_SYMBOL(lockdep_genl_is_held); | |
49 | #endif | |
50 | ||
def31174 PS |
51 | static void genl_lock_all(void) |
52 | { | |
53 | down_write(&cb_lock); | |
54 | genl_lock(); | |
55 | } | |
56 | ||
57 | static void genl_unlock_all(void) | |
58 | { | |
59 | genl_unlock(); | |
60 | up_write(&cb_lock); | |
61 | } | |
62 | ||
2ae0f17d | 63 | static DEFINE_IDR(genl_fam_idr); |
482a8524 | 64 | |
2dbba6f7 JB |
65 | /* |
66 | * Bitmap of multicast groups that are currently in use. | |
67 | * | |
68 | * To avoid an allocation at boot of just one unsigned long, | |
69 | * declare it global instead. | |
70 | * Bit 0 is marked as already used since group 0 is invalid. | |
e5dcecba JB |
71 | * Bit 1 is marked as already used since the drop-monitor code |
72 | * abuses the API and thinks it can statically use group 1. | |
73 | * That group will typically conflict with other groups that | |
74 | * any proper users use. | |
2a94fe48 JB |
75 | * Bit 16 is marked as used since it's used for generic netlink |
76 | * and the code no longer marks pre-reserved IDs as used. | |
2ecf7536 JB |
77 | * Bit 17 is marked as already used since the VFS quota code |
78 | * also abused this API and relied on family == group ID, we | |
79 | * cater to that by giving it a static family and group ID. | |
5e53e689 JB |
80 | * Bit 18 is marked as already used since the PMCRAID driver |
81 | * did the same thing as the VFS quota code (maybe copied?) | |
2dbba6f7 | 82 | */ |
2a94fe48 | 83 | static unsigned long mc_group_start = 0x3 | BIT(GENL_ID_CTRL) | |
5e53e689 JB |
84 | BIT(GENL_ID_VFS_DQUOT) | |
85 | BIT(GENL_ID_PMCRAID); | |
2dbba6f7 JB |
86 | static unsigned long *mc_groups = &mc_group_start; |
87 | static unsigned long mc_groups_longs = 1; | |
482a8524 | 88 | |
2ae0f17d | 89 | static int genl_ctrl_event(int event, const struct genl_family *family, |
2a94fe48 JB |
90 | const struct genl_multicast_group *grp, |
91 | int grp_id); | |
482a8524 | 92 | |
2ae0f17d | 93 | static const struct genl_family *genl_family_find_byid(unsigned int id) |
482a8524 | 94 | { |
2ae0f17d | 95 | return idr_find(&genl_fam_idr, id); |
482a8524 TG |
96 | } |
97 | ||
2ae0f17d | 98 | static const struct genl_family *genl_family_find_byname(char *name) |
482a8524 | 99 | { |
2ae0f17d JB |
100 | const struct genl_family *family; |
101 | unsigned int id; | |
482a8524 | 102 | |
2ae0f17d JB |
103 | idr_for_each_entry(&genl_fam_idr, family, id) |
104 | if (strcmp(family->name, name) == 0) | |
105 | return family; | |
482a8524 TG |
106 | |
107 | return NULL; | |
108 | } | |
109 | ||
2ae0f17d JB |
110 | static const struct genl_ops *genl_get_cmd(u8 cmd, |
111 | const struct genl_family *family) | |
482a8524 | 112 | { |
d91824c0 | 113 | int i; |
482a8524 | 114 | |
d91824c0 JB |
115 | for (i = 0; i < family->n_ops; i++) |
116 | if (family->ops[i].cmd == cmd) | |
117 | return &family->ops[i]; | |
482a8524 TG |
118 | |
119 | return NULL; | |
120 | } | |
121 | ||
2a94fe48 | 122 | static int genl_allocate_reserve_groups(int n_groups, int *first_id) |
2dbba6f7 | 123 | { |
2dbba6f7 | 124 | unsigned long *new_groups; |
2a94fe48 JB |
125 | int start = 0; |
126 | int i; | |
127 | int id; | |
128 | bool fits; | |
129 | ||
130 | do { | |
131 | if (start == 0) | |
132 | id = find_first_zero_bit(mc_groups, | |
133 | mc_groups_longs * | |
134 | BITS_PER_LONG); | |
135 | else | |
136 | id = find_next_zero_bit(mc_groups, | |
137 | mc_groups_longs * BITS_PER_LONG, | |
138 | start); | |
139 | ||
140 | fits = true; | |
141 | for (i = id; | |
142 | i < min_t(int, id + n_groups, | |
143 | mc_groups_longs * BITS_PER_LONG); | |
144 | i++) { | |
145 | if (test_bit(i, mc_groups)) { | |
146 | start = i; | |
147 | fits = false; | |
148 | break; | |
149 | } | |
150 | } | |
2dbba6f7 | 151 | |
b8e429a2 | 152 | if (id + n_groups > mc_groups_longs * BITS_PER_LONG) { |
2a94fe48 JB |
153 | unsigned long new_longs = mc_groups_longs + |
154 | BITS_TO_LONGS(n_groups); | |
155 | size_t nlen = new_longs * sizeof(unsigned long); | |
156 | ||
157 | if (mc_groups == &mc_group_start) { | |
158 | new_groups = kzalloc(nlen, GFP_KERNEL); | |
159 | if (!new_groups) | |
160 | return -ENOMEM; | |
161 | mc_groups = new_groups; | |
162 | *mc_groups = mc_group_start; | |
163 | } else { | |
164 | new_groups = krealloc(mc_groups, nlen, | |
165 | GFP_KERNEL); | |
166 | if (!new_groups) | |
167 | return -ENOMEM; | |
168 | mc_groups = new_groups; | |
169 | for (i = 0; i < BITS_TO_LONGS(n_groups); i++) | |
170 | mc_groups[mc_groups_longs + i] = 0; | |
171 | } | |
172 | mc_groups_longs = new_longs; | |
173 | } | |
174 | } while (!fits); | |
2dbba6f7 | 175 | |
2a94fe48 JB |
176 | for (i = id; i < id + n_groups; i++) |
177 | set_bit(i, mc_groups); | |
178 | *first_id = id; | |
179 | return 0; | |
180 | } | |
181 | ||
182 | static struct genl_family genl_ctrl; | |
183 | ||
184 | static int genl_validate_assign_mc_groups(struct genl_family *family) | |
185 | { | |
186 | int first_id; | |
187 | int n_groups = family->n_mcgrps; | |
0f0e2159 | 188 | int err = 0, i; |
2a94fe48 JB |
189 | bool groups_allocated = false; |
190 | ||
191 | if (!n_groups) | |
192 | return 0; | |
193 | ||
194 | for (i = 0; i < n_groups; i++) { | |
195 | const struct genl_multicast_group *grp = &family->mcgrps[i]; | |
196 | ||
197 | if (WARN_ON(grp->name[0] == '\0')) | |
198 | return -EINVAL; | |
199 | if (WARN_ON(memchr(grp->name, '\0', GENL_NAMSIZ) == NULL)) | |
200 | return -EINVAL; | |
201 | } | |
2dbba6f7 | 202 | |
e5dcecba | 203 | /* special-case our own group and hacks */ |
2a94fe48 JB |
204 | if (family == &genl_ctrl) { |
205 | first_id = GENL_ID_CTRL; | |
206 | BUG_ON(n_groups != 1); | |
207 | } else if (strcmp(family->name, "NET_DM") == 0) { | |
208 | first_id = 1; | |
209 | BUG_ON(n_groups != 1); | |
5e53e689 | 210 | } else if (family->id == GENL_ID_VFS_DQUOT) { |
2a94fe48 JB |
211 | first_id = GENL_ID_VFS_DQUOT; |
212 | BUG_ON(n_groups != 1); | |
5e53e689 JB |
213 | } else if (family->id == GENL_ID_PMCRAID) { |
214 | first_id = GENL_ID_PMCRAID; | |
215 | BUG_ON(n_groups != 1); | |
2a94fe48 JB |
216 | } else { |
217 | groups_allocated = true; | |
218 | err = genl_allocate_reserve_groups(n_groups, &first_id); | |
219 | if (err) | |
220 | return err; | |
2dbba6f7 JB |
221 | } |
222 | ||
2a94fe48 JB |
223 | family->mcgrp_offset = first_id; |
224 | ||
225 | /* if still initializing, can't and don't need to to realloc bitmaps */ | |
226 | if (!init_net.genl_sock) | |
227 | return 0; | |
228 | ||
134e6375 JB |
229 | if (family->netnsok) { |
230 | struct net *net; | |
231 | ||
d136f1bd | 232 | netlink_table_grab(); |
134e6375 JB |
233 | rcu_read_lock(); |
234 | for_each_net_rcu(net) { | |
d136f1bd | 235 | err = __netlink_change_ngroups(net->genl_sock, |
134e6375 JB |
236 | mc_groups_longs * BITS_PER_LONG); |
237 | if (err) { | |
238 | /* | |
239 | * No need to roll back, can only fail if | |
240 | * memory allocation fails and then the | |
241 | * number of _possible_ groups has been | |
242 | * increased on some sockets which is ok. | |
243 | */ | |
2a94fe48 | 244 | break; |
134e6375 JB |
245 | } |
246 | } | |
247 | rcu_read_unlock(); | |
d136f1bd | 248 | netlink_table_ungrab(); |
134e6375 JB |
249 | } else { |
250 | err = netlink_change_ngroups(init_net.genl_sock, | |
251 | mc_groups_longs * BITS_PER_LONG); | |
134e6375 | 252 | } |
2dbba6f7 | 253 | |
2a94fe48 JB |
254 | if (groups_allocated && err) { |
255 | for (i = 0; i < family->n_mcgrps; i++) | |
256 | clear_bit(family->mcgrp_offset + i, mc_groups); | |
257 | } | |
2dbba6f7 | 258 | |
79d310d0 | 259 | return err; |
2dbba6f7 | 260 | } |
2dbba6f7 | 261 | |
2ae0f17d | 262 | static void genl_unregister_mc_groups(const struct genl_family *family) |
79dc4386 | 263 | { |
134e6375 | 264 | struct net *net; |
2a94fe48 | 265 | int i; |
134e6375 | 266 | |
b8273570 | 267 | netlink_table_grab(); |
134e6375 | 268 | rcu_read_lock(); |
2a94fe48 JB |
269 | for_each_net_rcu(net) { |
270 | for (i = 0; i < family->n_mcgrps; i++) | |
271 | __netlink_clear_multicast_users( | |
272 | net->genl_sock, family->mcgrp_offset + i); | |
273 | } | |
134e6375 | 274 | rcu_read_unlock(); |
b8273570 | 275 | netlink_table_ungrab(); |
134e6375 | 276 | |
2a94fe48 JB |
277 | for (i = 0; i < family->n_mcgrps; i++) { |
278 | int grp_id = family->mcgrp_offset + i; | |
2dbba6f7 | 279 | |
2a94fe48 JB |
280 | if (grp_id != 1) |
281 | clear_bit(grp_id, mc_groups); | |
282 | genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, family, | |
283 | &family->mcgrps[i], grp_id); | |
284 | } | |
2dbba6f7 JB |
285 | } |
286 | ||
2f91abd4 | 287 | static int genl_validate_ops(const struct genl_family *family) |
482a8524 | 288 | { |
568508aa JB |
289 | const struct genl_ops *ops = family->ops; |
290 | unsigned int n_ops = family->n_ops; | |
d91824c0 JB |
291 | int i, j; |
292 | ||
568508aa JB |
293 | if (WARN_ON(n_ops && !ops)) |
294 | return -EINVAL; | |
295 | ||
296 | if (!n_ops) | |
297 | return 0; | |
298 | ||
d91824c0 JB |
299 | for (i = 0; i < n_ops; i++) { |
300 | if (ops[i].dumpit == NULL && ops[i].doit == NULL) | |
301 | return -EINVAL; | |
302 | for (j = i + 1; j < n_ops; j++) | |
303 | if (ops[i].cmd == ops[j].cmd) | |
304 | return -EINVAL; | |
482a8524 TG |
305 | } |
306 | ||
d91824c0 | 307 | return 0; |
482a8524 | 308 | } |
482a8524 TG |
309 | |
310 | /** | |
489111e5 | 311 | * genl_register_family - register a generic netlink family |
482a8524 TG |
312 | * @family: generic netlink family |
313 | * | |
314 | * Registers the specified family after validating it first. Only one | |
315 | * family may be registered with the same family name or identifier. | |
482a8524 | 316 | * |
489111e5 JB |
317 | * The family's ops, multicast groups and module pointer must already |
318 | * be assigned. | |
568508aa | 319 | * |
482a8524 TG |
320 | * Return 0 on success or a negative error code. |
321 | */ | |
489111e5 | 322 | int genl_register_family(struct genl_family *family) |
482a8524 | 323 | { |
a07ea4d9 | 324 | int err, i; |
2ae0f17d | 325 | int start = GENL_START_ALLOC, end = GENL_MAX_ID; |
482a8524 | 326 | |
568508aa JB |
327 | err = genl_validate_ops(family); |
328 | if (err) | |
329 | return err; | |
330 | ||
def31174 | 331 | genl_lock_all(); |
482a8524 TG |
332 | |
333 | if (genl_family_find_byname(family->name)) { | |
334 | err = -EEXIST; | |
335 | goto errout_locked; | |
336 | } | |
337 | ||
2ae0f17d JB |
338 | /* |
339 | * Sadly, a few cases need to be special-cased | |
340 | * due to them having previously abused the API | |
341 | * and having used their family ID also as their | |
342 | * multicast group ID, so we use reserved IDs | |
343 | * for both to be sure we can do that mapping. | |
344 | */ | |
a07ea4d9 | 345 | if (family == &genl_ctrl) { |
2ae0f17d JB |
346 | /* and this needs to be special for initial family lookups */ |
347 | start = end = GENL_ID_CTRL; | |
348 | } else if (strcmp(family->name, "pmcraid") == 0) { | |
349 | start = end = GENL_ID_PMCRAID; | |
350 | } else if (strcmp(family->name, "VFS_DQUOT") == 0) { | |
351 | start = end = GENL_ID_VFS_DQUOT; | |
482a8524 TG |
352 | } |
353 | ||
def31174 | 354 | if (family->maxattr && !family->parallel_ops) { |
482a8524 TG |
355 | family->attrbuf = kmalloc((family->maxattr+1) * |
356 | sizeof(struct nlattr *), GFP_KERNEL); | |
357 | if (family->attrbuf == NULL) { | |
358 | err = -ENOMEM; | |
e200bd80 | 359 | goto errout_locked; |
482a8524 TG |
360 | } |
361 | } else | |
362 | family->attrbuf = NULL; | |
363 | ||
2ae0f17d JB |
364 | family->id = idr_alloc(&genl_fam_idr, family, |
365 | start, end + 1, GFP_KERNEL); | |
22ca904a WY |
366 | if (family->id < 0) { |
367 | err = family->id; | |
2ae0f17d | 368 | goto errout_locked; |
22ca904a | 369 | } |
2ae0f17d | 370 | |
2a94fe48 JB |
371 | err = genl_validate_assign_mc_groups(family); |
372 | if (err) | |
2ae0f17d | 373 | goto errout_remove; |
2a94fe48 | 374 | |
def31174 | 375 | genl_unlock_all(); |
482a8524 | 376 | |
2a94fe48 JB |
377 | /* send all events */ |
378 | genl_ctrl_event(CTRL_CMD_NEWFAMILY, family, NULL, 0); | |
379 | for (i = 0; i < family->n_mcgrps; i++) | |
380 | genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, family, | |
381 | &family->mcgrps[i], family->mcgrp_offset + i); | |
482a8524 TG |
382 | |
383 | return 0; | |
384 | ||
2ae0f17d JB |
385 | errout_remove: |
386 | idr_remove(&genl_fam_idr, family->id); | |
00ffc1ba | 387 | kfree(family->attrbuf); |
482a8524 | 388 | errout_locked: |
def31174 | 389 | genl_unlock_all(); |
482a8524 TG |
390 | return err; |
391 | } | |
489111e5 | 392 | EXPORT_SYMBOL(genl_register_family); |
482a8524 TG |
393 | |
394 | /** | |
395 | * genl_unregister_family - unregister generic netlink family | |
396 | * @family: generic netlink family | |
397 | * | |
398 | * Unregisters the specified family. | |
399 | * | |
400 | * Returns 0 on success or a negative error code. | |
401 | */ | |
2ae0f17d | 402 | int genl_unregister_family(const struct genl_family *family) |
482a8524 | 403 | { |
def31174 | 404 | genl_lock_all(); |
482a8524 | 405 | |
0e82c763 | 406 | if (!genl_family_find_byid(family->id)) { |
2ae0f17d JB |
407 | genl_unlock_all(); |
408 | return -ENOENT; | |
409 | } | |
482a8524 | 410 | |
2ae0f17d | 411 | genl_unregister_mc_groups(family); |
ee1c2442 | 412 | |
2ae0f17d | 413 | idr_remove(&genl_fam_idr, family->id); |
482a8524 | 414 | |
2ae0f17d JB |
415 | up_write(&cb_lock); |
416 | wait_event(genl_sk_destructing_waitq, | |
417 | atomic_read(&genl_sk_destructing_cnt) == 0); | |
418 | genl_unlock(); | |
482a8524 | 419 | |
2ae0f17d | 420 | kfree(family->attrbuf); |
482a8524 | 421 | |
2ae0f17d JB |
422 | genl_ctrl_event(CTRL_CMD_DELFAMILY, family, NULL, 0); |
423 | ||
424 | return 0; | |
482a8524 | 425 | } |
416c2f9c | 426 | EXPORT_SYMBOL(genl_unregister_family); |
482a8524 | 427 | |
a46621a3 DV |
428 | /** |
429 | * genlmsg_put - Add generic netlink header to netlink message | |
430 | * @skb: socket buffer holding the message | |
15e47304 | 431 | * @portid: netlink portid the message is addressed to |
a46621a3 DV |
432 | * @seq: sequence number (usually the one of the sender) |
433 | * @family: generic netlink family | |
2c53040f | 434 | * @flags: netlink message flags |
a46621a3 DV |
435 | * @cmd: generic netlink command |
436 | * | |
437 | * Returns pointer to user specific header | |
438 | */ | |
15e47304 | 439 | void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, |
2ae0f17d | 440 | const struct genl_family *family, int flags, u8 cmd) |
a46621a3 DV |
441 | { |
442 | struct nlmsghdr *nlh; | |
443 | struct genlmsghdr *hdr; | |
444 | ||
15e47304 | 445 | nlh = nlmsg_put(skb, portid, seq, family->id, GENL_HDRLEN + |
a46621a3 DV |
446 | family->hdrsize, flags); |
447 | if (nlh == NULL) | |
448 | return NULL; | |
449 | ||
450 | hdr = nlmsg_data(nlh); | |
451 | hdr->cmd = cmd; | |
452 | hdr->version = family->version; | |
453 | hdr->reserved = 0; | |
454 | ||
455 | return (char *) hdr + GENL_HDRLEN; | |
456 | } | |
457 | EXPORT_SYMBOL(genlmsg_put); | |
458 | ||
fc9e50f5 TH |
459 | static int genl_lock_start(struct netlink_callback *cb) |
460 | { | |
461 | /* our ops are always const - netlink API doesn't propagate that */ | |
462 | const struct genl_ops *ops = cb->data; | |
463 | int rc = 0; | |
464 | ||
465 | if (ops->start) { | |
466 | genl_lock(); | |
467 | rc = ops->start(cb); | |
468 | genl_unlock(); | |
469 | } | |
470 | return rc; | |
471 | } | |
472 | ||
9b96309c PS |
473 | static int genl_lock_dumpit(struct sk_buff *skb, struct netlink_callback *cb) |
474 | { | |
f84f771d JB |
475 | /* our ops are always const - netlink API doesn't propagate that */ |
476 | const struct genl_ops *ops = cb->data; | |
9b96309c PS |
477 | int rc; |
478 | ||
479 | genl_lock(); | |
480 | rc = ops->dumpit(skb, cb); | |
481 | genl_unlock(); | |
482 | return rc; | |
483 | } | |
484 | ||
485 | static int genl_lock_done(struct netlink_callback *cb) | |
486 | { | |
f84f771d JB |
487 | /* our ops are always const - netlink API doesn't propagate that */ |
488 | const struct genl_ops *ops = cb->data; | |
9b96309c PS |
489 | int rc = 0; |
490 | ||
491 | if (ops->done) { | |
492 | genl_lock(); | |
493 | rc = ops->done(cb); | |
494 | genl_unlock(); | |
495 | } | |
496 | return rc; | |
497 | } | |
498 | ||
2ae0f17d | 499 | static int genl_family_rcv_msg(const struct genl_family *family, |
def31174 | 500 | struct sk_buff *skb, |
7ab606d1 JB |
501 | struct nlmsghdr *nlh, |
502 | struct netlink_ext_ack *extack) | |
482a8524 | 503 | { |
f84f771d | 504 | const struct genl_ops *ops; |
134e6375 | 505 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
506 | struct genl_info info; |
507 | struct genlmsghdr *hdr = nlmsg_data(nlh); | |
def31174 | 508 | struct nlattr **attrbuf; |
1d00a4eb | 509 | int hdrlen, err; |
482a8524 | 510 | |
134e6375 JB |
511 | /* this family doesn't exist in this netns */ |
512 | if (!family->netnsok && !net_eq(net, &init_net)) | |
513 | return -ENOENT; | |
514 | ||
482a8524 TG |
515 | hdrlen = GENL_HDRLEN + family->hdrsize; |
516 | if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) | |
1d00a4eb | 517 | return -EINVAL; |
482a8524 TG |
518 | |
519 | ops = genl_get_cmd(hdr->cmd, family); | |
1d00a4eb TG |
520 | if (ops == NULL) |
521 | return -EOPNOTSUPP; | |
482a8524 | 522 | |
1d00a4eb | 523 | if ((ops->flags & GENL_ADMIN_PERM) && |
90f62cf3 | 524 | !netlink_capable(skb, CAP_NET_ADMIN)) |
1d00a4eb | 525 | return -EPERM; |
482a8524 | 526 | |
4a92602a TA |
527 | if ((ops->flags & GENL_UNS_ADMIN_PERM) && |
528 | !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) | |
529 | return -EPERM; | |
530 | ||
e1ee3673 | 531 | if ((nlh->nlmsg_flags & NLM_F_DUMP) == NLM_F_DUMP) { |
9b96309c | 532 | int rc; |
def31174 | 533 | |
1d00a4eb TG |
534 | if (ops->dumpit == NULL) |
535 | return -EOPNOTSUPP; | |
482a8524 | 536 | |
9b96309c PS |
537 | if (!family->parallel_ops) { |
538 | struct netlink_dump_control c = { | |
33c6b1f6 | 539 | .module = family->module, |
f84f771d JB |
540 | /* we have const, but the netlink API doesn't */ |
541 | .data = (void *)ops, | |
fc9e50f5 | 542 | .start = genl_lock_start, |
9b96309c PS |
543 | .dump = genl_lock_dumpit, |
544 | .done = genl_lock_done, | |
545 | }; | |
546 | ||
547 | genl_unlock(); | |
33c6b1f6 | 548 | rc = __netlink_dump_start(net->genl_sock, skb, nlh, &c); |
9b96309c PS |
549 | genl_lock(); |
550 | ||
551 | } else { | |
552 | struct netlink_dump_control c = { | |
33c6b1f6 | 553 | .module = family->module, |
fc9e50f5 | 554 | .start = ops->start, |
9b96309c PS |
555 | .dump = ops->dumpit, |
556 | .done = ops->done, | |
557 | }; | |
558 | ||
33c6b1f6 | 559 | rc = __netlink_dump_start(net->genl_sock, skb, nlh, &c); |
9b96309c PS |
560 | } |
561 | ||
562 | return rc; | |
482a8524 TG |
563 | } |
564 | ||
1d00a4eb TG |
565 | if (ops->doit == NULL) |
566 | return -EOPNOTSUPP; | |
482a8524 | 567 | |
def31174 PS |
568 | if (family->maxattr && family->parallel_ops) { |
569 | attrbuf = kmalloc((family->maxattr+1) * | |
570 | sizeof(struct nlattr *), GFP_KERNEL); | |
571 | if (attrbuf == NULL) | |
572 | return -ENOMEM; | |
573 | } else | |
574 | attrbuf = family->attrbuf; | |
575 | ||
576 | if (attrbuf) { | |
577 | err = nlmsg_parse(nlh, hdrlen, attrbuf, family->maxattr, | |
fe52145f | 578 | ops->policy, extack); |
482a8524 | 579 | if (err < 0) |
50754d21 | 580 | goto out; |
482a8524 TG |
581 | } |
582 | ||
583 | info.snd_seq = nlh->nlmsg_seq; | |
15e47304 | 584 | info.snd_portid = NETLINK_CB(skb).portid; |
482a8524 TG |
585 | info.nlhdr = nlh; |
586 | info.genlhdr = nlmsg_data(nlh); | |
587 | info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN; | |
def31174 | 588 | info.attrs = attrbuf; |
7ab606d1 | 589 | info.extack = extack; |
134e6375 | 590 | genl_info_net_set(&info, net); |
ff4c92d8 | 591 | memset(&info.user_ptr, 0, sizeof(info.user_ptr)); |
482a8524 | 592 | |
ff4c92d8 JB |
593 | if (family->pre_doit) { |
594 | err = family->pre_doit(ops, skb, &info); | |
595 | if (err) | |
50754d21 | 596 | goto out; |
ff4c92d8 JB |
597 | } |
598 | ||
599 | err = ops->doit(skb, &info); | |
600 | ||
601 | if (family->post_doit) | |
602 | family->post_doit(ops, skb, &info); | |
603 | ||
50754d21 | 604 | out: |
def31174 PS |
605 | if (family->parallel_ops) |
606 | kfree(attrbuf); | |
607 | ||
608 | return err; | |
609 | } | |
610 | ||
2d4bc933 JB |
611 | static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, |
612 | struct netlink_ext_ack *extack) | |
def31174 | 613 | { |
2ae0f17d | 614 | const struct genl_family *family; |
def31174 PS |
615 | int err; |
616 | ||
617 | family = genl_family_find_byid(nlh->nlmsg_type); | |
618 | if (family == NULL) | |
619 | return -ENOENT; | |
620 | ||
621 | if (!family->parallel_ops) | |
622 | genl_lock(); | |
623 | ||
7ab606d1 | 624 | err = genl_family_rcv_msg(family, skb, nlh, extack); |
def31174 PS |
625 | |
626 | if (!family->parallel_ops) | |
627 | genl_unlock(); | |
628 | ||
ff4c92d8 | 629 | return err; |
482a8524 TG |
630 | } |
631 | ||
cd40b7d3 | 632 | static void genl_rcv(struct sk_buff *skb) |
482a8524 | 633 | { |
def31174 | 634 | down_read(&cb_lock); |
cd40b7d3 | 635 | netlink_rcv_skb(skb, &genl_rcv_msg); |
def31174 | 636 | up_read(&cb_lock); |
482a8524 TG |
637 | } |
638 | ||
639 | /************************************************************************** | |
640 | * Controller | |
641 | **************************************************************************/ | |
642 | ||
489111e5 | 643 | static struct genl_family genl_ctrl; |
17c157c8 | 644 | |
2ae0f17d | 645 | static int ctrl_fill_info(const struct genl_family *family, u32 portid, u32 seq, |
482a8524 TG |
646 | u32 flags, struct sk_buff *skb, u8 cmd) |
647 | { | |
648 | void *hdr; | |
649 | ||
15e47304 | 650 | hdr = genlmsg_put(skb, portid, seq, &genl_ctrl, flags, cmd); |
482a8524 TG |
651 | if (hdr == NULL) |
652 | return -1; | |
653 | ||
444653f6 DM |
654 | if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, family->name) || |
655 | nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, family->id) || | |
656 | nla_put_u32(skb, CTRL_ATTR_VERSION, family->version) || | |
657 | nla_put_u32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize) || | |
658 | nla_put_u32(skb, CTRL_ATTR_MAXATTR, family->maxattr)) | |
659 | goto nla_put_failure; | |
eb328111 | 660 | |
d91824c0 | 661 | if (family->n_ops) { |
e94ef682 | 662 | struct nlattr *nla_ops; |
d91824c0 | 663 | int i; |
eb328111 | 664 | |
e94ef682 TG |
665 | nla_ops = nla_nest_start(skb, CTRL_ATTR_OPS); |
666 | if (nla_ops == NULL) | |
eb328111 TG |
667 | goto nla_put_failure; |
668 | ||
d91824c0 | 669 | for (i = 0; i < family->n_ops; i++) { |
e94ef682 | 670 | struct nlattr *nest; |
f84f771d | 671 | const struct genl_ops *ops = &family->ops[i]; |
029b234f | 672 | u32 op_flags = ops->flags; |
f84f771d JB |
673 | |
674 | if (ops->dumpit) | |
029b234f | 675 | op_flags |= GENL_CMD_CAP_DUMP; |
f84f771d | 676 | if (ops->doit) |
029b234f | 677 | op_flags |= GENL_CMD_CAP_DO; |
f84f771d | 678 | if (ops->policy) |
029b234f | 679 | op_flags |= GENL_CMD_CAP_HASPOL; |
eb328111 | 680 | |
d91824c0 | 681 | nest = nla_nest_start(skb, i + 1); |
e94ef682 TG |
682 | if (nest == NULL) |
683 | goto nla_put_failure; | |
eb328111 | 684 | |
444653f6 | 685 | if (nla_put_u32(skb, CTRL_ATTR_OP_ID, ops->cmd) || |
029b234f | 686 | nla_put_u32(skb, CTRL_ATTR_OP_FLAGS, op_flags)) |
444653f6 | 687 | goto nla_put_failure; |
eb328111 | 688 | |
e94ef682 TG |
689 | nla_nest_end(skb, nest); |
690 | } | |
691 | ||
692 | nla_nest_end(skb, nla_ops); | |
693 | } | |
482a8524 | 694 | |
2a94fe48 | 695 | if (family->n_mcgrps) { |
2dbba6f7 | 696 | struct nlattr *nla_grps; |
2a94fe48 | 697 | int i; |
2dbba6f7 JB |
698 | |
699 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
700 | if (nla_grps == NULL) | |
701 | goto nla_put_failure; | |
702 | ||
2a94fe48 | 703 | for (i = 0; i < family->n_mcgrps; i++) { |
2dbba6f7 | 704 | struct nlattr *nest; |
2a94fe48 | 705 | const struct genl_multicast_group *grp; |
2dbba6f7 | 706 | |
2a94fe48 JB |
707 | grp = &family->mcgrps[i]; |
708 | ||
709 | nest = nla_nest_start(skb, i + 1); | |
2dbba6f7 JB |
710 | if (nest == NULL) |
711 | goto nla_put_failure; | |
712 | ||
2a94fe48 JB |
713 | if (nla_put_u32(skb, CTRL_ATTR_MCAST_GRP_ID, |
714 | family->mcgrp_offset + i) || | |
444653f6 DM |
715 | nla_put_string(skb, CTRL_ATTR_MCAST_GRP_NAME, |
716 | grp->name)) | |
717 | goto nla_put_failure; | |
2dbba6f7 JB |
718 | |
719 | nla_nest_end(skb, nest); | |
720 | } | |
721 | nla_nest_end(skb, nla_grps); | |
722 | } | |
723 | ||
053c095a JB |
724 | genlmsg_end(skb, hdr); |
725 | return 0; | |
2dbba6f7 JB |
726 | |
727 | nla_put_failure: | |
bc3ed28c TG |
728 | genlmsg_cancel(skb, hdr); |
729 | return -EMSGSIZE; | |
2dbba6f7 JB |
730 | } |
731 | ||
2ae0f17d | 732 | static int ctrl_fill_mcgrp_info(const struct genl_family *family, |
2a94fe48 JB |
733 | const struct genl_multicast_group *grp, |
734 | int grp_id, u32 portid, u32 seq, u32 flags, | |
735 | struct sk_buff *skb, u8 cmd) | |
2dbba6f7 JB |
736 | { |
737 | void *hdr; | |
738 | struct nlattr *nla_grps; | |
739 | struct nlattr *nest; | |
740 | ||
15e47304 | 741 | hdr = genlmsg_put(skb, portid, seq, &genl_ctrl, flags, cmd); |
2dbba6f7 JB |
742 | if (hdr == NULL) |
743 | return -1; | |
744 | ||
c2ebb908 JB |
745 | if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, family->name) || |
746 | nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, family->id)) | |
444653f6 | 747 | goto nla_put_failure; |
2dbba6f7 JB |
748 | |
749 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
750 | if (nla_grps == NULL) | |
751 | goto nla_put_failure; | |
752 | ||
753 | nest = nla_nest_start(skb, 1); | |
754 | if (nest == NULL) | |
755 | goto nla_put_failure; | |
756 | ||
2a94fe48 | 757 | if (nla_put_u32(skb, CTRL_ATTR_MCAST_GRP_ID, grp_id) || |
444653f6 DM |
758 | nla_put_string(skb, CTRL_ATTR_MCAST_GRP_NAME, |
759 | grp->name)) | |
760 | goto nla_put_failure; | |
2dbba6f7 JB |
761 | |
762 | nla_nest_end(skb, nest); | |
763 | nla_nest_end(skb, nla_grps); | |
764 | ||
053c095a JB |
765 | genlmsg_end(skb, hdr); |
766 | return 0; | |
482a8524 TG |
767 | |
768 | nla_put_failure: | |
bc3ed28c TG |
769 | genlmsg_cancel(skb, hdr); |
770 | return -EMSGSIZE; | |
482a8524 TG |
771 | } |
772 | ||
773 | static int ctrl_dumpfamily(struct sk_buff *skb, struct netlink_callback *cb) | |
774 | { | |
2ae0f17d | 775 | int n = 0; |
482a8524 | 776 | struct genl_family *rt; |
134e6375 | 777 | struct net *net = sock_net(skb->sk); |
2ae0f17d JB |
778 | int fams_to_skip = cb->args[0]; |
779 | unsigned int id; | |
482a8524 | 780 | |
2ae0f17d JB |
781 | idr_for_each_entry(&genl_fam_idr, rt, id) { |
782 | if (!rt->netnsok && !net_eq(net, &init_net)) | |
783 | continue; | |
784 | ||
785 | if (n++ < fams_to_skip) | |
786 | continue; | |
482a8524 | 787 | |
2ae0f17d JB |
788 | if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).portid, |
789 | cb->nlh->nlmsg_seq, NLM_F_MULTI, | |
1d2a6a5e SG |
790 | skb, CTRL_CMD_NEWFAMILY) < 0) { |
791 | n--; | |
2ae0f17d | 792 | break; |
1d2a6a5e | 793 | } |
2ae0f17d | 794 | } |
482a8524 | 795 | |
2ae0f17d | 796 | cb->args[0] = n; |
482a8524 TG |
797 | return skb->len; |
798 | } | |
799 | ||
2ae0f17d | 800 | static struct sk_buff *ctrl_build_family_msg(const struct genl_family *family, |
15e47304 | 801 | u32 portid, int seq, u8 cmd) |
482a8524 TG |
802 | { |
803 | struct sk_buff *skb; | |
804 | int err; | |
805 | ||
339bf98f | 806 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); |
482a8524 TG |
807 | if (skb == NULL) |
808 | return ERR_PTR(-ENOBUFS); | |
809 | ||
15e47304 | 810 | err = ctrl_fill_info(family, portid, seq, 0, skb, cmd); |
482a8524 TG |
811 | if (err < 0) { |
812 | nlmsg_free(skb); | |
813 | return ERR_PTR(err); | |
814 | } | |
815 | ||
816 | return skb; | |
817 | } | |
818 | ||
2a94fe48 | 819 | static struct sk_buff * |
2ae0f17d | 820 | ctrl_build_mcgrp_msg(const struct genl_family *family, |
2a94fe48 JB |
821 | const struct genl_multicast_group *grp, |
822 | int grp_id, u32 portid, int seq, u8 cmd) | |
2dbba6f7 JB |
823 | { |
824 | struct sk_buff *skb; | |
825 | int err; | |
826 | ||
827 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); | |
828 | if (skb == NULL) | |
829 | return ERR_PTR(-ENOBUFS); | |
830 | ||
2a94fe48 JB |
831 | err = ctrl_fill_mcgrp_info(family, grp, grp_id, portid, |
832 | seq, 0, skb, cmd); | |
2dbba6f7 JB |
833 | if (err < 0) { |
834 | nlmsg_free(skb); | |
835 | return ERR_PTR(err); | |
836 | } | |
837 | ||
838 | return skb; | |
839 | } | |
840 | ||
ef7c79ed | 841 | static const struct nla_policy ctrl_policy[CTRL_ATTR_MAX+1] = { |
482a8524 | 842 | [CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 }, |
5176f91e TG |
843 | [CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING, |
844 | .len = GENL_NAMSIZ - 1 }, | |
482a8524 TG |
845 | }; |
846 | ||
847 | static int ctrl_getfamily(struct sk_buff *skb, struct genl_info *info) | |
848 | { | |
849 | struct sk_buff *msg; | |
2ae0f17d | 850 | const struct genl_family *res = NULL; |
482a8524 TG |
851 | int err = -EINVAL; |
852 | ||
853 | if (info->attrs[CTRL_ATTR_FAMILY_ID]) { | |
854 | u16 id = nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]); | |
855 | res = genl_family_find_byid(id); | |
134e6375 | 856 | err = -ENOENT; |
482a8524 TG |
857 | } |
858 | ||
859 | if (info->attrs[CTRL_ATTR_FAMILY_NAME]) { | |
5176f91e | 860 | char *name; |
482a8524 | 861 | |
5176f91e | 862 | name = nla_data(info->attrs[CTRL_ATTR_FAMILY_NAME]); |
482a8524 | 863 | res = genl_family_find_byname(name); |
fa843095 SH |
864 | #ifdef CONFIG_MODULES |
865 | if (res == NULL) { | |
866 | genl_unlock(); | |
c74f2b26 | 867 | up_read(&cb_lock); |
e9412c37 | 868 | request_module("net-pf-%d-proto-%d-family-%s", |
fa843095 | 869 | PF_NETLINK, NETLINK_GENERIC, name); |
c74f2b26 | 870 | down_read(&cb_lock); |
fa843095 SH |
871 | genl_lock(); |
872 | res = genl_family_find_byname(name); | |
873 | } | |
874 | #endif | |
134e6375 | 875 | err = -ENOENT; |
482a8524 TG |
876 | } |
877 | ||
134e6375 JB |
878 | if (res == NULL) |
879 | return err; | |
880 | ||
881 | if (!res->netnsok && !net_eq(genl_info_net(info), &init_net)) { | |
882 | /* family doesn't exist here */ | |
883 | return -ENOENT; | |
482a8524 TG |
884 | } |
885 | ||
15e47304 | 886 | msg = ctrl_build_family_msg(res, info->snd_portid, info->snd_seq, |
2dbba6f7 | 887 | CTRL_CMD_NEWFAMILY); |
134e6375 JB |
888 | if (IS_ERR(msg)) |
889 | return PTR_ERR(msg); | |
482a8524 | 890 | |
134e6375 | 891 | return genlmsg_reply(msg, info); |
482a8524 TG |
892 | } |
893 | ||
2ae0f17d | 894 | static int genl_ctrl_event(int event, const struct genl_family *family, |
2a94fe48 JB |
895 | const struct genl_multicast_group *grp, |
896 | int grp_id) | |
482a8524 TG |
897 | { |
898 | struct sk_buff *msg; | |
899 | ||
134e6375 JB |
900 | /* genl is still initialising */ |
901 | if (!init_net.genl_sock) | |
482a8524 TG |
902 | return 0; |
903 | ||
904 | switch (event) { | |
905 | case CTRL_CMD_NEWFAMILY: | |
906 | case CTRL_CMD_DELFAMILY: | |
c2ebb908 | 907 | WARN_ON(grp); |
134e6375 | 908 | msg = ctrl_build_family_msg(family, 0, 0, event); |
2dbba6f7 JB |
909 | break; |
910 | case CTRL_CMD_NEWMCAST_GRP: | |
911 | case CTRL_CMD_DELMCAST_GRP: | |
c2ebb908 | 912 | BUG_ON(!grp); |
2a94fe48 | 913 | msg = ctrl_build_mcgrp_msg(family, grp, grp_id, 0, 0, event); |
482a8524 | 914 | break; |
134e6375 JB |
915 | default: |
916 | return -EINVAL; | |
917 | } | |
918 | ||
919 | if (IS_ERR(msg)) | |
920 | return PTR_ERR(msg); | |
921 | ||
922 | if (!family->netnsok) { | |
68eb5503 | 923 | genlmsg_multicast_netns(&genl_ctrl, &init_net, msg, 0, |
2a94fe48 | 924 | 0, GFP_KERNEL); |
134e6375 JB |
925 | } else { |
926 | rcu_read_lock(); | |
68eb5503 | 927 | genlmsg_multicast_allns(&genl_ctrl, msg, 0, |
2a94fe48 | 928 | 0, GFP_ATOMIC); |
134e6375 | 929 | rcu_read_unlock(); |
482a8524 TG |
930 | } |
931 | ||
932 | return 0; | |
933 | } | |
934 | ||
12d8de6d | 935 | static const struct genl_ops genl_ctrl_ops[] = { |
c53ed742 JB |
936 | { |
937 | .cmd = CTRL_CMD_GETFAMILY, | |
938 | .doit = ctrl_getfamily, | |
939 | .dumpit = ctrl_dumpfamily, | |
940 | .policy = ctrl_policy, | |
941 | }, | |
482a8524 TG |
942 | }; |
943 | ||
12d8de6d | 944 | static const struct genl_multicast_group genl_ctrl_groups[] = { |
2a94fe48 | 945 | { .name = "notify", }, |
2dbba6f7 JB |
946 | }; |
947 | ||
56989f6d | 948 | static struct genl_family genl_ctrl __ro_after_init = { |
489111e5 JB |
949 | .module = THIS_MODULE, |
950 | .ops = genl_ctrl_ops, | |
951 | .n_ops = ARRAY_SIZE(genl_ctrl_ops), | |
952 | .mcgrps = genl_ctrl_groups, | |
953 | .n_mcgrps = ARRAY_SIZE(genl_ctrl_groups), | |
954 | .id = GENL_ID_CTRL, | |
955 | .name = "nlctrl", | |
956 | .version = 0x2, | |
957 | .maxattr = CTRL_ATTR_MAX, | |
958 | .netnsok = true, | |
959 | }; | |
960 | ||
023e2cfa | 961 | static int genl_bind(struct net *net, int group) |
c380d9a7 | 962 | { |
2ae0f17d JB |
963 | struct genl_family *f; |
964 | int err = -ENOENT; | |
965 | unsigned int id; | |
c380d9a7 JB |
966 | |
967 | down_read(&cb_lock); | |
2ae0f17d JB |
968 | |
969 | idr_for_each_entry(&genl_fam_idr, f, id) { | |
970 | if (group >= f->mcgrp_offset && | |
971 | group < f->mcgrp_offset + f->n_mcgrps) { | |
972 | int fam_grp = group - f->mcgrp_offset; | |
973 | ||
974 | if (!f->netnsok && net != &init_net) | |
975 | err = -ENOENT; | |
976 | else if (f->mcast_bind) | |
977 | err = f->mcast_bind(net, fam_grp); | |
978 | else | |
979 | err = 0; | |
980 | break; | |
c380d9a7 JB |
981 | } |
982 | } | |
983 | up_read(&cb_lock); | |
984 | ||
c380d9a7 JB |
985 | return err; |
986 | } | |
987 | ||
023e2cfa | 988 | static void genl_unbind(struct net *net, int group) |
c380d9a7 | 989 | { |
2ae0f17d JB |
990 | struct genl_family *f; |
991 | unsigned int id; | |
c380d9a7 JB |
992 | |
993 | down_read(&cb_lock); | |
c380d9a7 | 994 | |
2ae0f17d JB |
995 | idr_for_each_entry(&genl_fam_idr, f, id) { |
996 | if (group >= f->mcgrp_offset && | |
997 | group < f->mcgrp_offset + f->n_mcgrps) { | |
998 | int fam_grp = group - f->mcgrp_offset; | |
c380d9a7 | 999 | |
2ae0f17d JB |
1000 | if (f->mcast_unbind) |
1001 | f->mcast_unbind(net, fam_grp); | |
1002 | break; | |
c380d9a7 JB |
1003 | } |
1004 | } | |
1005 | up_read(&cb_lock); | |
c380d9a7 JB |
1006 | } |
1007 | ||
134e6375 JB |
1008 | static int __net_init genl_pernet_init(struct net *net) |
1009 | { | |
a31f2d17 PNA |
1010 | struct netlink_kernel_cfg cfg = { |
1011 | .input = genl_rcv, | |
9785e10a | 1012 | .flags = NL_CFG_F_NONROOT_RECV, |
c380d9a7 JB |
1013 | .bind = genl_bind, |
1014 | .unbind = genl_unbind, | |
a31f2d17 PNA |
1015 | }; |
1016 | ||
134e6375 | 1017 | /* we'll bump the group number right afterwards */ |
9f00d977 | 1018 | net->genl_sock = netlink_kernel_create(net, NETLINK_GENERIC, &cfg); |
134e6375 JB |
1019 | |
1020 | if (!net->genl_sock && net_eq(net, &init_net)) | |
1021 | panic("GENL: Cannot initialize generic netlink\n"); | |
1022 | ||
1023 | if (!net->genl_sock) | |
1024 | return -ENOMEM; | |
1025 | ||
1026 | return 0; | |
1027 | } | |
1028 | ||
1029 | static void __net_exit genl_pernet_exit(struct net *net) | |
1030 | { | |
1031 | netlink_kernel_release(net->genl_sock); | |
1032 | net->genl_sock = NULL; | |
1033 | } | |
1034 | ||
1035 | static struct pernet_operations genl_pernet_ops = { | |
1036 | .init = genl_pernet_init, | |
1037 | .exit = genl_pernet_exit, | |
1038 | }; | |
1039 | ||
482a8524 TG |
1040 | static int __init genl_init(void) |
1041 | { | |
2ae0f17d | 1042 | int err; |
482a8524 | 1043 | |
489111e5 | 1044 | err = genl_register_family(&genl_ctrl); |
482a8524 | 1045 | if (err < 0) |
134e6375 | 1046 | goto problem; |
482a8524 | 1047 | |
134e6375 JB |
1048 | err = register_pernet_subsys(&genl_pernet_ops); |
1049 | if (err) | |
1050 | goto problem; | |
482a8524 TG |
1051 | |
1052 | return 0; | |
1053 | ||
134e6375 | 1054 | problem: |
482a8524 | 1055 | panic("GENL: Cannot register controller: %d\n", err); |
482a8524 TG |
1056 | } |
1057 | ||
1058 | subsys_initcall(genl_init); | |
1059 | ||
c90c39da JB |
1060 | /** |
1061 | * genl_family_attrbuf - return family's attrbuf | |
1062 | * @family: the family | |
1063 | * | |
1064 | * Return the family's attrbuf, while validating that it's | |
1065 | * actually valid to access it. | |
1066 | * | |
1067 | * You cannot use this function with a family that has parallel_ops | |
1068 | * and you can only use it within (pre/post) doit/dumpit callbacks. | |
1069 | */ | |
2ae0f17d | 1070 | struct nlattr **genl_family_attrbuf(const struct genl_family *family) |
c90c39da JB |
1071 | { |
1072 | if (!WARN_ON(family->parallel_ops)) | |
1073 | lockdep_assert_held(&genl_mutex); | |
1074 | ||
1075 | return family->attrbuf; | |
1076 | } | |
1077 | EXPORT_SYMBOL(genl_family_attrbuf); | |
1078 | ||
15e47304 | 1079 | static int genlmsg_mcast(struct sk_buff *skb, u32 portid, unsigned long group, |
134e6375 JB |
1080 | gfp_t flags) |
1081 | { | |
1082 | struct sk_buff *tmp; | |
1083 | struct net *net, *prev = NULL; | |
cb9f7a9a | 1084 | bool delivered = false; |
134e6375 JB |
1085 | int err; |
1086 | ||
1087 | for_each_net_rcu(net) { | |
1088 | if (prev) { | |
1089 | tmp = skb_clone(skb, flags); | |
1090 | if (!tmp) { | |
1091 | err = -ENOMEM; | |
1092 | goto error; | |
1093 | } | |
1094 | err = nlmsg_multicast(prev->genl_sock, tmp, | |
15e47304 | 1095 | portid, group, flags); |
cb9f7a9a ND |
1096 | if (!err) |
1097 | delivered = true; | |
1098 | else if (err != -ESRCH) | |
134e6375 JB |
1099 | goto error; |
1100 | } | |
1101 | ||
1102 | prev = net; | |
1103 | } | |
1104 | ||
cb9f7a9a ND |
1105 | err = nlmsg_multicast(prev->genl_sock, skb, portid, group, flags); |
1106 | if (!err) | |
1107 | delivered = true; | |
1108 | else if (err != -ESRCH) | |
02a2385f | 1109 | return err; |
cb9f7a9a | 1110 | return delivered ? 0 : -ESRCH; |
134e6375 JB |
1111 | error: |
1112 | kfree_skb(skb); | |
1113 | return err; | |
1114 | } | |
1115 | ||
2ae0f17d JB |
1116 | int genlmsg_multicast_allns(const struct genl_family *family, |
1117 | struct sk_buff *skb, u32 portid, | |
1118 | unsigned int group, gfp_t flags) | |
134e6375 | 1119 | { |
220815a9 | 1120 | if (WARN_ON_ONCE(group >= family->n_mcgrps)) |
2a94fe48 JB |
1121 | return -EINVAL; |
1122 | group = family->mcgrp_offset + group; | |
15e47304 | 1123 | return genlmsg_mcast(skb, portid, group, flags); |
134e6375 JB |
1124 | } |
1125 | EXPORT_SYMBOL(genlmsg_multicast_allns); | |
263ba61d | 1126 | |
2ae0f17d | 1127 | void genl_notify(const struct genl_family *family, struct sk_buff *skb, |
92c14d9b | 1128 | struct genl_info *info, u32 group, gfp_t flags) |
263ba61d | 1129 | { |
92c14d9b | 1130 | struct net *net = genl_info_net(info); |
263ba61d PS |
1131 | struct sock *sk = net->genl_sock; |
1132 | int report = 0; | |
1133 | ||
92c14d9b JB |
1134 | if (info->nlhdr) |
1135 | report = nlmsg_report(info->nlhdr); | |
263ba61d | 1136 | |
220815a9 | 1137 | if (WARN_ON_ONCE(group >= family->n_mcgrps)) |
2a94fe48 JB |
1138 | return; |
1139 | group = family->mcgrp_offset + group; | |
92c14d9b | 1140 | nlmsg_notify(sk, skb, info->snd_portid, group, report, flags); |
263ba61d PS |
1141 | } |
1142 | EXPORT_SYMBOL(genl_notify); |