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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) { |
6da2ec56 KC |
355 | family->attrbuf = kmalloc_array(family->maxattr + 1, |
356 | sizeof(struct nlattr *), | |
357 | GFP_KERNEL); | |
482a8524 TG |
358 | if (family->attrbuf == NULL) { |
359 | err = -ENOMEM; | |
e200bd80 | 360 | goto errout_locked; |
482a8524 TG |
361 | } |
362 | } else | |
363 | family->attrbuf = NULL; | |
364 | ||
2ae0f17d JB |
365 | family->id = idr_alloc(&genl_fam_idr, family, |
366 | start, end + 1, GFP_KERNEL); | |
22ca904a WY |
367 | if (family->id < 0) { |
368 | err = family->id; | |
2ae0f17d | 369 | goto errout_locked; |
22ca904a | 370 | } |
2ae0f17d | 371 | |
2a94fe48 JB |
372 | err = genl_validate_assign_mc_groups(family); |
373 | if (err) | |
2ae0f17d | 374 | goto errout_remove; |
2a94fe48 | 375 | |
def31174 | 376 | genl_unlock_all(); |
482a8524 | 377 | |
2a94fe48 JB |
378 | /* send all events */ |
379 | genl_ctrl_event(CTRL_CMD_NEWFAMILY, family, NULL, 0); | |
380 | for (i = 0; i < family->n_mcgrps; i++) | |
381 | genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, family, | |
382 | &family->mcgrps[i], family->mcgrp_offset + i); | |
482a8524 TG |
383 | |
384 | return 0; | |
385 | ||
2ae0f17d JB |
386 | errout_remove: |
387 | idr_remove(&genl_fam_idr, family->id); | |
00ffc1ba | 388 | kfree(family->attrbuf); |
482a8524 | 389 | errout_locked: |
def31174 | 390 | genl_unlock_all(); |
482a8524 TG |
391 | return err; |
392 | } | |
489111e5 | 393 | EXPORT_SYMBOL(genl_register_family); |
482a8524 TG |
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 | */ | |
2ae0f17d | 403 | int genl_unregister_family(const struct genl_family *family) |
482a8524 | 404 | { |
def31174 | 405 | genl_lock_all(); |
482a8524 | 406 | |
0e82c763 | 407 | if (!genl_family_find_byid(family->id)) { |
2ae0f17d JB |
408 | genl_unlock_all(); |
409 | return -ENOENT; | |
410 | } | |
482a8524 | 411 | |
2ae0f17d | 412 | genl_unregister_mc_groups(family); |
ee1c2442 | 413 | |
2ae0f17d | 414 | idr_remove(&genl_fam_idr, family->id); |
482a8524 | 415 | |
2ae0f17d JB |
416 | up_write(&cb_lock); |
417 | wait_event(genl_sk_destructing_waitq, | |
418 | atomic_read(&genl_sk_destructing_cnt) == 0); | |
419 | genl_unlock(); | |
482a8524 | 420 | |
2ae0f17d | 421 | kfree(family->attrbuf); |
482a8524 | 422 | |
2ae0f17d JB |
423 | genl_ctrl_event(CTRL_CMD_DELFAMILY, family, NULL, 0); |
424 | ||
425 | return 0; | |
482a8524 | 426 | } |
416c2f9c | 427 | EXPORT_SYMBOL(genl_unregister_family); |
482a8524 | 428 | |
a46621a3 DV |
429 | /** |
430 | * genlmsg_put - Add generic netlink header to netlink message | |
431 | * @skb: socket buffer holding the message | |
15e47304 | 432 | * @portid: netlink portid the message is addressed to |
a46621a3 DV |
433 | * @seq: sequence number (usually the one of the sender) |
434 | * @family: generic netlink family | |
2c53040f | 435 | * @flags: netlink message flags |
a46621a3 DV |
436 | * @cmd: generic netlink command |
437 | * | |
438 | * Returns pointer to user specific header | |
439 | */ | |
15e47304 | 440 | void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, |
2ae0f17d | 441 | const struct genl_family *family, int flags, u8 cmd) |
a46621a3 DV |
442 | { |
443 | struct nlmsghdr *nlh; | |
444 | struct genlmsghdr *hdr; | |
445 | ||
15e47304 | 446 | nlh = nlmsg_put(skb, portid, seq, family->id, GENL_HDRLEN + |
a46621a3 DV |
447 | family->hdrsize, flags); |
448 | if (nlh == NULL) | |
449 | return NULL; | |
450 | ||
451 | hdr = nlmsg_data(nlh); | |
452 | hdr->cmd = cmd; | |
453 | hdr->version = family->version; | |
454 | hdr->reserved = 0; | |
455 | ||
456 | return (char *) hdr + GENL_HDRLEN; | |
457 | } | |
458 | EXPORT_SYMBOL(genlmsg_put); | |
459 | ||
fc9e50f5 TH |
460 | static int genl_lock_start(struct netlink_callback *cb) |
461 | { | |
462 | /* our ops are always const - netlink API doesn't propagate that */ | |
463 | const struct genl_ops *ops = cb->data; | |
464 | int rc = 0; | |
465 | ||
466 | if (ops->start) { | |
467 | genl_lock(); | |
468 | rc = ops->start(cb); | |
469 | genl_unlock(); | |
470 | } | |
471 | return rc; | |
472 | } | |
473 | ||
9b96309c PS |
474 | static int genl_lock_dumpit(struct sk_buff *skb, struct netlink_callback *cb) |
475 | { | |
f84f771d JB |
476 | /* our ops are always const - netlink API doesn't propagate that */ |
477 | const struct genl_ops *ops = cb->data; | |
9b96309c PS |
478 | int rc; |
479 | ||
480 | genl_lock(); | |
481 | rc = ops->dumpit(skb, cb); | |
482 | genl_unlock(); | |
483 | return rc; | |
484 | } | |
485 | ||
486 | static int genl_lock_done(struct netlink_callback *cb) | |
487 | { | |
f84f771d JB |
488 | /* our ops are always const - netlink API doesn't propagate that */ |
489 | const struct genl_ops *ops = cb->data; | |
9b96309c PS |
490 | int rc = 0; |
491 | ||
492 | if (ops->done) { | |
493 | genl_lock(); | |
494 | rc = ops->done(cb); | |
495 | genl_unlock(); | |
496 | } | |
497 | return rc; | |
498 | } | |
499 | ||
2ae0f17d | 500 | static int genl_family_rcv_msg(const struct genl_family *family, |
def31174 | 501 | struct sk_buff *skb, |
7ab606d1 JB |
502 | struct nlmsghdr *nlh, |
503 | struct netlink_ext_ack *extack) | |
482a8524 | 504 | { |
f84f771d | 505 | const struct genl_ops *ops; |
134e6375 | 506 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
507 | struct genl_info info; |
508 | struct genlmsghdr *hdr = nlmsg_data(nlh); | |
def31174 | 509 | struct nlattr **attrbuf; |
1d00a4eb | 510 | int hdrlen, err; |
482a8524 | 511 | |
134e6375 JB |
512 | /* this family doesn't exist in this netns */ |
513 | if (!family->netnsok && !net_eq(net, &init_net)) | |
514 | return -ENOENT; | |
515 | ||
482a8524 TG |
516 | hdrlen = GENL_HDRLEN + family->hdrsize; |
517 | if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) | |
1d00a4eb | 518 | return -EINVAL; |
482a8524 TG |
519 | |
520 | ops = genl_get_cmd(hdr->cmd, family); | |
1d00a4eb TG |
521 | if (ops == NULL) |
522 | return -EOPNOTSUPP; | |
482a8524 | 523 | |
1d00a4eb | 524 | if ((ops->flags & GENL_ADMIN_PERM) && |
90f62cf3 | 525 | !netlink_capable(skb, CAP_NET_ADMIN)) |
1d00a4eb | 526 | return -EPERM; |
482a8524 | 527 | |
4a92602a TA |
528 | if ((ops->flags & GENL_UNS_ADMIN_PERM) && |
529 | !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) | |
530 | return -EPERM; | |
531 | ||
e1ee3673 | 532 | if ((nlh->nlmsg_flags & NLM_F_DUMP) == NLM_F_DUMP) { |
9b96309c | 533 | int rc; |
def31174 | 534 | |
1d00a4eb TG |
535 | if (ops->dumpit == NULL) |
536 | return -EOPNOTSUPP; | |
482a8524 | 537 | |
9b96309c PS |
538 | if (!family->parallel_ops) { |
539 | struct netlink_dump_control c = { | |
33c6b1f6 | 540 | .module = family->module, |
f84f771d JB |
541 | /* we have const, but the netlink API doesn't */ |
542 | .data = (void *)ops, | |
fc9e50f5 | 543 | .start = genl_lock_start, |
9b96309c PS |
544 | .dump = genl_lock_dumpit, |
545 | .done = genl_lock_done, | |
546 | }; | |
547 | ||
548 | genl_unlock(); | |
33c6b1f6 | 549 | rc = __netlink_dump_start(net->genl_sock, skb, nlh, &c); |
9b96309c PS |
550 | genl_lock(); |
551 | ||
552 | } else { | |
553 | struct netlink_dump_control c = { | |
33c6b1f6 | 554 | .module = family->module, |
fc9e50f5 | 555 | .start = ops->start, |
9b96309c PS |
556 | .dump = ops->dumpit, |
557 | .done = ops->done, | |
558 | }; | |
559 | ||
33c6b1f6 | 560 | rc = __netlink_dump_start(net->genl_sock, skb, nlh, &c); |
9b96309c PS |
561 | } |
562 | ||
563 | return rc; | |
482a8524 TG |
564 | } |
565 | ||
1d00a4eb TG |
566 | if (ops->doit == NULL) |
567 | return -EOPNOTSUPP; | |
482a8524 | 568 | |
def31174 | 569 | if (family->maxattr && family->parallel_ops) { |
6da2ec56 KC |
570 | attrbuf = kmalloc_array(family->maxattr + 1, |
571 | sizeof(struct nlattr *), | |
572 | GFP_KERNEL); | |
def31174 PS |
573 | if (attrbuf == NULL) |
574 | return -ENOMEM; | |
575 | } else | |
576 | attrbuf = family->attrbuf; | |
577 | ||
578 | if (attrbuf) { | |
579 | err = nlmsg_parse(nlh, hdrlen, attrbuf, family->maxattr, | |
fe52145f | 580 | ops->policy, extack); |
482a8524 | 581 | if (err < 0) |
50754d21 | 582 | goto out; |
482a8524 TG |
583 | } |
584 | ||
585 | info.snd_seq = nlh->nlmsg_seq; | |
15e47304 | 586 | info.snd_portid = NETLINK_CB(skb).portid; |
482a8524 TG |
587 | info.nlhdr = nlh; |
588 | info.genlhdr = nlmsg_data(nlh); | |
589 | info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN; | |
def31174 | 590 | info.attrs = attrbuf; |
7ab606d1 | 591 | info.extack = extack; |
134e6375 | 592 | genl_info_net_set(&info, net); |
ff4c92d8 | 593 | memset(&info.user_ptr, 0, sizeof(info.user_ptr)); |
482a8524 | 594 | |
ff4c92d8 JB |
595 | if (family->pre_doit) { |
596 | err = family->pre_doit(ops, skb, &info); | |
597 | if (err) | |
50754d21 | 598 | goto out; |
ff4c92d8 JB |
599 | } |
600 | ||
601 | err = ops->doit(skb, &info); | |
602 | ||
603 | if (family->post_doit) | |
604 | family->post_doit(ops, skb, &info); | |
605 | ||
50754d21 | 606 | out: |
def31174 PS |
607 | if (family->parallel_ops) |
608 | kfree(attrbuf); | |
609 | ||
610 | return err; | |
611 | } | |
612 | ||
2d4bc933 JB |
613 | static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, |
614 | struct netlink_ext_ack *extack) | |
def31174 | 615 | { |
2ae0f17d | 616 | const struct genl_family *family; |
def31174 PS |
617 | int err; |
618 | ||
619 | family = genl_family_find_byid(nlh->nlmsg_type); | |
620 | if (family == NULL) | |
621 | return -ENOENT; | |
622 | ||
623 | if (!family->parallel_ops) | |
624 | genl_lock(); | |
625 | ||
7ab606d1 | 626 | err = genl_family_rcv_msg(family, skb, nlh, extack); |
def31174 PS |
627 | |
628 | if (!family->parallel_ops) | |
629 | genl_unlock(); | |
630 | ||
ff4c92d8 | 631 | return err; |
482a8524 TG |
632 | } |
633 | ||
cd40b7d3 | 634 | static void genl_rcv(struct sk_buff *skb) |
482a8524 | 635 | { |
def31174 | 636 | down_read(&cb_lock); |
cd40b7d3 | 637 | netlink_rcv_skb(skb, &genl_rcv_msg); |
def31174 | 638 | up_read(&cb_lock); |
482a8524 TG |
639 | } |
640 | ||
641 | /************************************************************************** | |
642 | * Controller | |
643 | **************************************************************************/ | |
644 | ||
489111e5 | 645 | static struct genl_family genl_ctrl; |
17c157c8 | 646 | |
2ae0f17d | 647 | static int ctrl_fill_info(const struct genl_family *family, u32 portid, u32 seq, |
482a8524 TG |
648 | u32 flags, struct sk_buff *skb, u8 cmd) |
649 | { | |
650 | void *hdr; | |
651 | ||
15e47304 | 652 | hdr = genlmsg_put(skb, portid, seq, &genl_ctrl, flags, cmd); |
482a8524 TG |
653 | if (hdr == NULL) |
654 | return -1; | |
655 | ||
444653f6 DM |
656 | if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, family->name) || |
657 | nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, family->id) || | |
658 | nla_put_u32(skb, CTRL_ATTR_VERSION, family->version) || | |
659 | nla_put_u32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize) || | |
660 | nla_put_u32(skb, CTRL_ATTR_MAXATTR, family->maxattr)) | |
661 | goto nla_put_failure; | |
eb328111 | 662 | |
d91824c0 | 663 | if (family->n_ops) { |
e94ef682 | 664 | struct nlattr *nla_ops; |
d91824c0 | 665 | int i; |
eb328111 | 666 | |
e94ef682 TG |
667 | nla_ops = nla_nest_start(skb, CTRL_ATTR_OPS); |
668 | if (nla_ops == NULL) | |
eb328111 TG |
669 | goto nla_put_failure; |
670 | ||
d91824c0 | 671 | for (i = 0; i < family->n_ops; i++) { |
e94ef682 | 672 | struct nlattr *nest; |
f84f771d | 673 | const struct genl_ops *ops = &family->ops[i]; |
029b234f | 674 | u32 op_flags = ops->flags; |
f84f771d JB |
675 | |
676 | if (ops->dumpit) | |
029b234f | 677 | op_flags |= GENL_CMD_CAP_DUMP; |
f84f771d | 678 | if (ops->doit) |
029b234f | 679 | op_flags |= GENL_CMD_CAP_DO; |
f84f771d | 680 | if (ops->policy) |
029b234f | 681 | op_flags |= GENL_CMD_CAP_HASPOL; |
eb328111 | 682 | |
d91824c0 | 683 | nest = nla_nest_start(skb, i + 1); |
e94ef682 TG |
684 | if (nest == NULL) |
685 | goto nla_put_failure; | |
eb328111 | 686 | |
444653f6 | 687 | if (nla_put_u32(skb, CTRL_ATTR_OP_ID, ops->cmd) || |
029b234f | 688 | nla_put_u32(skb, CTRL_ATTR_OP_FLAGS, op_flags)) |
444653f6 | 689 | goto nla_put_failure; |
eb328111 | 690 | |
e94ef682 TG |
691 | nla_nest_end(skb, nest); |
692 | } | |
693 | ||
694 | nla_nest_end(skb, nla_ops); | |
695 | } | |
482a8524 | 696 | |
2a94fe48 | 697 | if (family->n_mcgrps) { |
2dbba6f7 | 698 | struct nlattr *nla_grps; |
2a94fe48 | 699 | int i; |
2dbba6f7 JB |
700 | |
701 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
702 | if (nla_grps == NULL) | |
703 | goto nla_put_failure; | |
704 | ||
2a94fe48 | 705 | for (i = 0; i < family->n_mcgrps; i++) { |
2dbba6f7 | 706 | struct nlattr *nest; |
2a94fe48 | 707 | const struct genl_multicast_group *grp; |
2dbba6f7 | 708 | |
2a94fe48 JB |
709 | grp = &family->mcgrps[i]; |
710 | ||
711 | nest = nla_nest_start(skb, i + 1); | |
2dbba6f7 JB |
712 | if (nest == NULL) |
713 | goto nla_put_failure; | |
714 | ||
2a94fe48 JB |
715 | if (nla_put_u32(skb, CTRL_ATTR_MCAST_GRP_ID, |
716 | family->mcgrp_offset + i) || | |
444653f6 DM |
717 | nla_put_string(skb, CTRL_ATTR_MCAST_GRP_NAME, |
718 | grp->name)) | |
719 | goto nla_put_failure; | |
2dbba6f7 JB |
720 | |
721 | nla_nest_end(skb, nest); | |
722 | } | |
723 | nla_nest_end(skb, nla_grps); | |
724 | } | |
725 | ||
053c095a JB |
726 | genlmsg_end(skb, hdr); |
727 | return 0; | |
2dbba6f7 JB |
728 | |
729 | nla_put_failure: | |
bc3ed28c TG |
730 | genlmsg_cancel(skb, hdr); |
731 | return -EMSGSIZE; | |
2dbba6f7 JB |
732 | } |
733 | ||
2ae0f17d | 734 | static int ctrl_fill_mcgrp_info(const struct genl_family *family, |
2a94fe48 JB |
735 | const struct genl_multicast_group *grp, |
736 | int grp_id, u32 portid, u32 seq, u32 flags, | |
737 | struct sk_buff *skb, u8 cmd) | |
2dbba6f7 JB |
738 | { |
739 | void *hdr; | |
740 | struct nlattr *nla_grps; | |
741 | struct nlattr *nest; | |
742 | ||
15e47304 | 743 | hdr = genlmsg_put(skb, portid, seq, &genl_ctrl, flags, cmd); |
2dbba6f7 JB |
744 | if (hdr == NULL) |
745 | return -1; | |
746 | ||
c2ebb908 JB |
747 | if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, family->name) || |
748 | nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, family->id)) | |
444653f6 | 749 | goto nla_put_failure; |
2dbba6f7 JB |
750 | |
751 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
752 | if (nla_grps == NULL) | |
753 | goto nla_put_failure; | |
754 | ||
755 | nest = nla_nest_start(skb, 1); | |
756 | if (nest == NULL) | |
757 | goto nla_put_failure; | |
758 | ||
2a94fe48 | 759 | if (nla_put_u32(skb, CTRL_ATTR_MCAST_GRP_ID, grp_id) || |
444653f6 DM |
760 | nla_put_string(skb, CTRL_ATTR_MCAST_GRP_NAME, |
761 | grp->name)) | |
762 | goto nla_put_failure; | |
2dbba6f7 JB |
763 | |
764 | nla_nest_end(skb, nest); | |
765 | nla_nest_end(skb, nla_grps); | |
766 | ||
053c095a JB |
767 | genlmsg_end(skb, hdr); |
768 | return 0; | |
482a8524 TG |
769 | |
770 | nla_put_failure: | |
bc3ed28c TG |
771 | genlmsg_cancel(skb, hdr); |
772 | return -EMSGSIZE; | |
482a8524 TG |
773 | } |
774 | ||
775 | static int ctrl_dumpfamily(struct sk_buff *skb, struct netlink_callback *cb) | |
776 | { | |
2ae0f17d | 777 | int n = 0; |
482a8524 | 778 | struct genl_family *rt; |
134e6375 | 779 | struct net *net = sock_net(skb->sk); |
2ae0f17d JB |
780 | int fams_to_skip = cb->args[0]; |
781 | unsigned int id; | |
482a8524 | 782 | |
2ae0f17d JB |
783 | idr_for_each_entry(&genl_fam_idr, rt, id) { |
784 | if (!rt->netnsok && !net_eq(net, &init_net)) | |
785 | continue; | |
786 | ||
787 | if (n++ < fams_to_skip) | |
788 | continue; | |
482a8524 | 789 | |
2ae0f17d JB |
790 | if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).portid, |
791 | cb->nlh->nlmsg_seq, NLM_F_MULTI, | |
1d2a6a5e SG |
792 | skb, CTRL_CMD_NEWFAMILY) < 0) { |
793 | n--; | |
2ae0f17d | 794 | break; |
1d2a6a5e | 795 | } |
2ae0f17d | 796 | } |
482a8524 | 797 | |
2ae0f17d | 798 | cb->args[0] = n; |
482a8524 TG |
799 | return skb->len; |
800 | } | |
801 | ||
2ae0f17d | 802 | static struct sk_buff *ctrl_build_family_msg(const struct genl_family *family, |
15e47304 | 803 | u32 portid, int seq, u8 cmd) |
482a8524 TG |
804 | { |
805 | struct sk_buff *skb; | |
806 | int err; | |
807 | ||
339bf98f | 808 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); |
482a8524 TG |
809 | if (skb == NULL) |
810 | return ERR_PTR(-ENOBUFS); | |
811 | ||
15e47304 | 812 | err = ctrl_fill_info(family, portid, seq, 0, skb, cmd); |
482a8524 TG |
813 | if (err < 0) { |
814 | nlmsg_free(skb); | |
815 | return ERR_PTR(err); | |
816 | } | |
817 | ||
818 | return skb; | |
819 | } | |
820 | ||
2a94fe48 | 821 | static struct sk_buff * |
2ae0f17d | 822 | ctrl_build_mcgrp_msg(const struct genl_family *family, |
2a94fe48 JB |
823 | const struct genl_multicast_group *grp, |
824 | int grp_id, u32 portid, int seq, u8 cmd) | |
2dbba6f7 JB |
825 | { |
826 | struct sk_buff *skb; | |
827 | int err; | |
828 | ||
829 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); | |
830 | if (skb == NULL) | |
831 | return ERR_PTR(-ENOBUFS); | |
832 | ||
2a94fe48 JB |
833 | err = ctrl_fill_mcgrp_info(family, grp, grp_id, portid, |
834 | seq, 0, skb, cmd); | |
2dbba6f7 JB |
835 | if (err < 0) { |
836 | nlmsg_free(skb); | |
837 | return ERR_PTR(err); | |
838 | } | |
839 | ||
840 | return skb; | |
841 | } | |
842 | ||
ef7c79ed | 843 | static const struct nla_policy ctrl_policy[CTRL_ATTR_MAX+1] = { |
482a8524 | 844 | [CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 }, |
5176f91e TG |
845 | [CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING, |
846 | .len = GENL_NAMSIZ - 1 }, | |
482a8524 TG |
847 | }; |
848 | ||
849 | static int ctrl_getfamily(struct sk_buff *skb, struct genl_info *info) | |
850 | { | |
851 | struct sk_buff *msg; | |
2ae0f17d | 852 | const struct genl_family *res = NULL; |
482a8524 TG |
853 | int err = -EINVAL; |
854 | ||
855 | if (info->attrs[CTRL_ATTR_FAMILY_ID]) { | |
856 | u16 id = nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]); | |
857 | res = genl_family_find_byid(id); | |
134e6375 | 858 | err = -ENOENT; |
482a8524 TG |
859 | } |
860 | ||
861 | if (info->attrs[CTRL_ATTR_FAMILY_NAME]) { | |
5176f91e | 862 | char *name; |
482a8524 | 863 | |
5176f91e | 864 | name = nla_data(info->attrs[CTRL_ATTR_FAMILY_NAME]); |
482a8524 | 865 | res = genl_family_find_byname(name); |
fa843095 SH |
866 | #ifdef CONFIG_MODULES |
867 | if (res == NULL) { | |
868 | genl_unlock(); | |
c74f2b26 | 869 | up_read(&cb_lock); |
e9412c37 | 870 | request_module("net-pf-%d-proto-%d-family-%s", |
fa843095 | 871 | PF_NETLINK, NETLINK_GENERIC, name); |
c74f2b26 | 872 | down_read(&cb_lock); |
fa843095 SH |
873 | genl_lock(); |
874 | res = genl_family_find_byname(name); | |
875 | } | |
876 | #endif | |
134e6375 | 877 | err = -ENOENT; |
482a8524 TG |
878 | } |
879 | ||
134e6375 JB |
880 | if (res == NULL) |
881 | return err; | |
882 | ||
883 | if (!res->netnsok && !net_eq(genl_info_net(info), &init_net)) { | |
884 | /* family doesn't exist here */ | |
885 | return -ENOENT; | |
482a8524 TG |
886 | } |
887 | ||
15e47304 | 888 | msg = ctrl_build_family_msg(res, info->snd_portid, info->snd_seq, |
2dbba6f7 | 889 | CTRL_CMD_NEWFAMILY); |
134e6375 JB |
890 | if (IS_ERR(msg)) |
891 | return PTR_ERR(msg); | |
482a8524 | 892 | |
134e6375 | 893 | return genlmsg_reply(msg, info); |
482a8524 TG |
894 | } |
895 | ||
2ae0f17d | 896 | static int genl_ctrl_event(int event, const struct genl_family *family, |
2a94fe48 JB |
897 | const struct genl_multicast_group *grp, |
898 | int grp_id) | |
482a8524 TG |
899 | { |
900 | struct sk_buff *msg; | |
901 | ||
134e6375 JB |
902 | /* genl is still initialising */ |
903 | if (!init_net.genl_sock) | |
482a8524 TG |
904 | return 0; |
905 | ||
906 | switch (event) { | |
907 | case CTRL_CMD_NEWFAMILY: | |
908 | case CTRL_CMD_DELFAMILY: | |
c2ebb908 | 909 | WARN_ON(grp); |
134e6375 | 910 | msg = ctrl_build_family_msg(family, 0, 0, event); |
2dbba6f7 JB |
911 | break; |
912 | case CTRL_CMD_NEWMCAST_GRP: | |
913 | case CTRL_CMD_DELMCAST_GRP: | |
c2ebb908 | 914 | BUG_ON(!grp); |
2a94fe48 | 915 | msg = ctrl_build_mcgrp_msg(family, grp, grp_id, 0, 0, event); |
482a8524 | 916 | break; |
134e6375 JB |
917 | default: |
918 | return -EINVAL; | |
919 | } | |
920 | ||
921 | if (IS_ERR(msg)) | |
922 | return PTR_ERR(msg); | |
923 | ||
924 | if (!family->netnsok) { | |
68eb5503 | 925 | genlmsg_multicast_netns(&genl_ctrl, &init_net, msg, 0, |
2a94fe48 | 926 | 0, GFP_KERNEL); |
134e6375 JB |
927 | } else { |
928 | rcu_read_lock(); | |
68eb5503 | 929 | genlmsg_multicast_allns(&genl_ctrl, msg, 0, |
2a94fe48 | 930 | 0, GFP_ATOMIC); |
134e6375 | 931 | rcu_read_unlock(); |
482a8524 TG |
932 | } |
933 | ||
934 | return 0; | |
935 | } | |
936 | ||
12d8de6d | 937 | static const struct genl_ops genl_ctrl_ops[] = { |
c53ed742 JB |
938 | { |
939 | .cmd = CTRL_CMD_GETFAMILY, | |
940 | .doit = ctrl_getfamily, | |
941 | .dumpit = ctrl_dumpfamily, | |
942 | .policy = ctrl_policy, | |
943 | }, | |
482a8524 TG |
944 | }; |
945 | ||
12d8de6d | 946 | static const struct genl_multicast_group genl_ctrl_groups[] = { |
2a94fe48 | 947 | { .name = "notify", }, |
2dbba6f7 JB |
948 | }; |
949 | ||
56989f6d | 950 | static struct genl_family genl_ctrl __ro_after_init = { |
489111e5 JB |
951 | .module = THIS_MODULE, |
952 | .ops = genl_ctrl_ops, | |
953 | .n_ops = ARRAY_SIZE(genl_ctrl_ops), | |
954 | .mcgrps = genl_ctrl_groups, | |
955 | .n_mcgrps = ARRAY_SIZE(genl_ctrl_groups), | |
956 | .id = GENL_ID_CTRL, | |
957 | .name = "nlctrl", | |
958 | .version = 0x2, | |
959 | .maxattr = CTRL_ATTR_MAX, | |
960 | .netnsok = true, | |
961 | }; | |
962 | ||
023e2cfa | 963 | static int genl_bind(struct net *net, int group) |
c380d9a7 | 964 | { |
2ae0f17d JB |
965 | struct genl_family *f; |
966 | int err = -ENOENT; | |
967 | unsigned int id; | |
c380d9a7 JB |
968 | |
969 | down_read(&cb_lock); | |
2ae0f17d JB |
970 | |
971 | idr_for_each_entry(&genl_fam_idr, f, id) { | |
972 | if (group >= f->mcgrp_offset && | |
973 | group < f->mcgrp_offset + f->n_mcgrps) { | |
974 | int fam_grp = group - f->mcgrp_offset; | |
975 | ||
976 | if (!f->netnsok && net != &init_net) | |
977 | err = -ENOENT; | |
978 | else if (f->mcast_bind) | |
979 | err = f->mcast_bind(net, fam_grp); | |
980 | else | |
981 | err = 0; | |
982 | break; | |
c380d9a7 JB |
983 | } |
984 | } | |
985 | up_read(&cb_lock); | |
986 | ||
c380d9a7 JB |
987 | return err; |
988 | } | |
989 | ||
023e2cfa | 990 | static void genl_unbind(struct net *net, int group) |
c380d9a7 | 991 | { |
2ae0f17d JB |
992 | struct genl_family *f; |
993 | unsigned int id; | |
c380d9a7 JB |
994 | |
995 | down_read(&cb_lock); | |
c380d9a7 | 996 | |
2ae0f17d JB |
997 | idr_for_each_entry(&genl_fam_idr, f, id) { |
998 | if (group >= f->mcgrp_offset && | |
999 | group < f->mcgrp_offset + f->n_mcgrps) { | |
1000 | int fam_grp = group - f->mcgrp_offset; | |
c380d9a7 | 1001 | |
2ae0f17d JB |
1002 | if (f->mcast_unbind) |
1003 | f->mcast_unbind(net, fam_grp); | |
1004 | break; | |
c380d9a7 JB |
1005 | } |
1006 | } | |
1007 | up_read(&cb_lock); | |
c380d9a7 JB |
1008 | } |
1009 | ||
134e6375 JB |
1010 | static int __net_init genl_pernet_init(struct net *net) |
1011 | { | |
a31f2d17 PNA |
1012 | struct netlink_kernel_cfg cfg = { |
1013 | .input = genl_rcv, | |
9785e10a | 1014 | .flags = NL_CFG_F_NONROOT_RECV, |
c380d9a7 JB |
1015 | .bind = genl_bind, |
1016 | .unbind = genl_unbind, | |
a31f2d17 PNA |
1017 | }; |
1018 | ||
134e6375 | 1019 | /* we'll bump the group number right afterwards */ |
9f00d977 | 1020 | net->genl_sock = netlink_kernel_create(net, NETLINK_GENERIC, &cfg); |
134e6375 JB |
1021 | |
1022 | if (!net->genl_sock && net_eq(net, &init_net)) | |
1023 | panic("GENL: Cannot initialize generic netlink\n"); | |
1024 | ||
1025 | if (!net->genl_sock) | |
1026 | return -ENOMEM; | |
1027 | ||
1028 | return 0; | |
1029 | } | |
1030 | ||
1031 | static void __net_exit genl_pernet_exit(struct net *net) | |
1032 | { | |
1033 | netlink_kernel_release(net->genl_sock); | |
1034 | net->genl_sock = NULL; | |
1035 | } | |
1036 | ||
1037 | static struct pernet_operations genl_pernet_ops = { | |
1038 | .init = genl_pernet_init, | |
1039 | .exit = genl_pernet_exit, | |
1040 | }; | |
1041 | ||
482a8524 TG |
1042 | static int __init genl_init(void) |
1043 | { | |
2ae0f17d | 1044 | int err; |
482a8524 | 1045 | |
489111e5 | 1046 | err = genl_register_family(&genl_ctrl); |
482a8524 | 1047 | if (err < 0) |
134e6375 | 1048 | goto problem; |
482a8524 | 1049 | |
134e6375 JB |
1050 | err = register_pernet_subsys(&genl_pernet_ops); |
1051 | if (err) | |
1052 | goto problem; | |
482a8524 TG |
1053 | |
1054 | return 0; | |
1055 | ||
134e6375 | 1056 | problem: |
482a8524 | 1057 | panic("GENL: Cannot register controller: %d\n", err); |
482a8524 TG |
1058 | } |
1059 | ||
1060 | subsys_initcall(genl_init); | |
1061 | ||
c90c39da JB |
1062 | /** |
1063 | * genl_family_attrbuf - return family's attrbuf | |
1064 | * @family: the family | |
1065 | * | |
1066 | * Return the family's attrbuf, while validating that it's | |
1067 | * actually valid to access it. | |
1068 | * | |
1069 | * You cannot use this function with a family that has parallel_ops | |
1070 | * and you can only use it within (pre/post) doit/dumpit callbacks. | |
1071 | */ | |
2ae0f17d | 1072 | struct nlattr **genl_family_attrbuf(const struct genl_family *family) |
c90c39da JB |
1073 | { |
1074 | if (!WARN_ON(family->parallel_ops)) | |
1075 | lockdep_assert_held(&genl_mutex); | |
1076 | ||
1077 | return family->attrbuf; | |
1078 | } | |
1079 | EXPORT_SYMBOL(genl_family_attrbuf); | |
1080 | ||
15e47304 | 1081 | static int genlmsg_mcast(struct sk_buff *skb, u32 portid, unsigned long group, |
134e6375 JB |
1082 | gfp_t flags) |
1083 | { | |
1084 | struct sk_buff *tmp; | |
1085 | struct net *net, *prev = NULL; | |
cb9f7a9a | 1086 | bool delivered = false; |
134e6375 JB |
1087 | int err; |
1088 | ||
1089 | for_each_net_rcu(net) { | |
1090 | if (prev) { | |
1091 | tmp = skb_clone(skb, flags); | |
1092 | if (!tmp) { | |
1093 | err = -ENOMEM; | |
1094 | goto error; | |
1095 | } | |
1096 | err = nlmsg_multicast(prev->genl_sock, tmp, | |
15e47304 | 1097 | portid, group, flags); |
cb9f7a9a ND |
1098 | if (!err) |
1099 | delivered = true; | |
1100 | else if (err != -ESRCH) | |
134e6375 JB |
1101 | goto error; |
1102 | } | |
1103 | ||
1104 | prev = net; | |
1105 | } | |
1106 | ||
cb9f7a9a ND |
1107 | err = nlmsg_multicast(prev->genl_sock, skb, portid, group, flags); |
1108 | if (!err) | |
1109 | delivered = true; | |
1110 | else if (err != -ESRCH) | |
02a2385f | 1111 | return err; |
cb9f7a9a | 1112 | return delivered ? 0 : -ESRCH; |
134e6375 JB |
1113 | error: |
1114 | kfree_skb(skb); | |
1115 | return err; | |
1116 | } | |
1117 | ||
2ae0f17d JB |
1118 | int genlmsg_multicast_allns(const struct genl_family *family, |
1119 | struct sk_buff *skb, u32 portid, | |
1120 | unsigned int group, gfp_t flags) | |
134e6375 | 1121 | { |
220815a9 | 1122 | if (WARN_ON_ONCE(group >= family->n_mcgrps)) |
2a94fe48 JB |
1123 | return -EINVAL; |
1124 | group = family->mcgrp_offset + group; | |
15e47304 | 1125 | return genlmsg_mcast(skb, portid, group, flags); |
134e6375 JB |
1126 | } |
1127 | EXPORT_SYMBOL(genlmsg_multicast_allns); | |
263ba61d | 1128 | |
2ae0f17d | 1129 | void genl_notify(const struct genl_family *family, struct sk_buff *skb, |
92c14d9b | 1130 | struct genl_info *info, u32 group, gfp_t flags) |
263ba61d | 1131 | { |
92c14d9b | 1132 | struct net *net = genl_info_net(info); |
263ba61d PS |
1133 | struct sock *sk = net->genl_sock; |
1134 | int report = 0; | |
1135 | ||
92c14d9b JB |
1136 | if (info->nlhdr) |
1137 | report = nlmsg_report(info->nlhdr); | |
263ba61d | 1138 | |
220815a9 | 1139 | if (WARN_ON_ONCE(group >= family->n_mcgrps)) |
2a94fe48 JB |
1140 | return; |
1141 | group = family->mcgrp_offset + group; | |
92c14d9b | 1142 | nlmsg_notify(sk, skb, info->snd_portid, group, report, flags); |
263ba61d PS |
1143 | } |
1144 | EXPORT_SYMBOL(genl_notify); |