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