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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> |
482a8524 TG |
20 | #include <net/sock.h> |
21 | #include <net/genetlink.h> | |
22 | ||
14cc3e2b | 23 | static DEFINE_MUTEX(genl_mutex); /* serialization of message processing */ |
def31174 | 24 | static DECLARE_RWSEM(cb_lock); |
482a8524 | 25 | |
ee1c2442 JB |
26 | atomic_t genl_sk_destructing_cnt = ATOMIC_INIT(0); |
27 | DECLARE_WAIT_QUEUE_HEAD(genl_sk_destructing_waitq); | |
28 | ||
f408e0ce | 29 | void genl_lock(void) |
482a8524 | 30 | { |
14cc3e2b | 31 | mutex_lock(&genl_mutex); |
482a8524 | 32 | } |
f408e0ce | 33 | EXPORT_SYMBOL(genl_lock); |
482a8524 | 34 | |
f408e0ce | 35 | void genl_unlock(void) |
482a8524 | 36 | { |
14cc3e2b | 37 | mutex_unlock(&genl_mutex); |
482a8524 | 38 | } |
f408e0ce | 39 | EXPORT_SYMBOL(genl_unlock); |
482a8524 | 40 | |
320f5ea0 | 41 | #ifdef CONFIG_LOCKDEP |
61d03535 | 42 | bool lockdep_genl_is_held(void) |
86b1309c PS |
43 | { |
44 | return lockdep_is_held(&genl_mutex); | |
45 | } | |
46 | EXPORT_SYMBOL(lockdep_genl_is_held); | |
47 | #endif | |
48 | ||
def31174 PS |
49 | static void genl_lock_all(void) |
50 | { | |
51 | down_write(&cb_lock); | |
52 | genl_lock(); | |
53 | } | |
54 | ||
55 | static void genl_unlock_all(void) | |
56 | { | |
57 | genl_unlock(); | |
58 | up_write(&cb_lock); | |
59 | } | |
60 | ||
482a8524 TG |
61 | #define GENL_FAM_TAB_SIZE 16 |
62 | #define GENL_FAM_TAB_MASK (GENL_FAM_TAB_SIZE - 1) | |
63 | ||
64 | static struct list_head family_ht[GENL_FAM_TAB_SIZE]; | |
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 | |
c2ebb908 | 89 | static int genl_ctrl_event(int event, struct genl_family *family, |
2a94fe48 JB |
90 | const struct genl_multicast_group *grp, |
91 | int grp_id); | |
482a8524 TG |
92 | |
93 | static inline unsigned int genl_family_hash(unsigned int id) | |
94 | { | |
95 | return id & GENL_FAM_TAB_MASK; | |
96 | } | |
97 | ||
98 | static inline struct list_head *genl_family_chain(unsigned int id) | |
99 | { | |
100 | return &family_ht[genl_family_hash(id)]; | |
101 | } | |
102 | ||
103 | static struct genl_family *genl_family_find_byid(unsigned int id) | |
104 | { | |
105 | struct genl_family *f; | |
106 | ||
107 | list_for_each_entry(f, genl_family_chain(id), family_list) | |
108 | if (f->id == id) | |
109 | return f; | |
110 | ||
111 | return NULL; | |
112 | } | |
113 | ||
114 | static struct genl_family *genl_family_find_byname(char *name) | |
115 | { | |
116 | struct genl_family *f; | |
117 | int i; | |
118 | ||
119 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) | |
120 | list_for_each_entry(f, genl_family_chain(i), family_list) | |
121 | if (strcmp(f->name, name) == 0) | |
122 | return f; | |
123 | ||
124 | return NULL; | |
125 | } | |
126 | ||
f84f771d | 127 | static const struct genl_ops *genl_get_cmd(u8 cmd, struct genl_family *family) |
482a8524 | 128 | { |
d91824c0 | 129 | int i; |
482a8524 | 130 | |
d91824c0 JB |
131 | for (i = 0; i < family->n_ops; i++) |
132 | if (family->ops[i].cmd == cmd) | |
133 | return &family->ops[i]; | |
482a8524 TG |
134 | |
135 | return NULL; | |
136 | } | |
137 | ||
138 | /* Of course we are going to have problems once we hit | |
139 | * 2^16 alive types, but that can only happen by year 2K | |
140 | */ | |
b57ef81f | 141 | static u16 genl_generate_id(void) |
482a8524 | 142 | { |
988ade6b KK |
143 | static u16 id_gen_idx = GENL_MIN_ID; |
144 | int i; | |
482a8524 | 145 | |
988ade6b | 146 | for (i = 0; i <= GENL_MAX_ID - GENL_MIN_ID; i++) { |
2ecf7536 | 147 | if (id_gen_idx != GENL_ID_VFS_DQUOT && |
5e53e689 | 148 | id_gen_idx != GENL_ID_PMCRAID && |
2ecf7536 | 149 | !genl_family_find_byid(id_gen_idx)) |
988ade6b KK |
150 | return id_gen_idx; |
151 | if (++id_gen_idx > GENL_MAX_ID) | |
482a8524 | 152 | id_gen_idx = GENL_MIN_ID; |
988ade6b | 153 | } |
482a8524 | 154 | |
988ade6b | 155 | return 0; |
482a8524 TG |
156 | } |
157 | ||
2a94fe48 | 158 | static int genl_allocate_reserve_groups(int n_groups, int *first_id) |
2dbba6f7 | 159 | { |
2dbba6f7 | 160 | unsigned long *new_groups; |
2a94fe48 JB |
161 | int start = 0; |
162 | int i; | |
163 | int id; | |
164 | bool fits; | |
165 | ||
166 | do { | |
167 | if (start == 0) | |
168 | id = find_first_zero_bit(mc_groups, | |
169 | mc_groups_longs * | |
170 | BITS_PER_LONG); | |
171 | else | |
172 | id = find_next_zero_bit(mc_groups, | |
173 | mc_groups_longs * BITS_PER_LONG, | |
174 | start); | |
175 | ||
176 | fits = true; | |
177 | for (i = id; | |
178 | i < min_t(int, id + n_groups, | |
179 | mc_groups_longs * BITS_PER_LONG); | |
180 | i++) { | |
181 | if (test_bit(i, mc_groups)) { | |
182 | start = i; | |
183 | fits = false; | |
184 | break; | |
185 | } | |
186 | } | |
2dbba6f7 | 187 | |
b8e429a2 | 188 | if (id + n_groups > mc_groups_longs * BITS_PER_LONG) { |
2a94fe48 JB |
189 | unsigned long new_longs = mc_groups_longs + |
190 | BITS_TO_LONGS(n_groups); | |
191 | size_t nlen = new_longs * sizeof(unsigned long); | |
192 | ||
193 | if (mc_groups == &mc_group_start) { | |
194 | new_groups = kzalloc(nlen, GFP_KERNEL); | |
195 | if (!new_groups) | |
196 | return -ENOMEM; | |
197 | mc_groups = new_groups; | |
198 | *mc_groups = mc_group_start; | |
199 | } else { | |
200 | new_groups = krealloc(mc_groups, nlen, | |
201 | GFP_KERNEL); | |
202 | if (!new_groups) | |
203 | return -ENOMEM; | |
204 | mc_groups = new_groups; | |
205 | for (i = 0; i < BITS_TO_LONGS(n_groups); i++) | |
206 | mc_groups[mc_groups_longs + i] = 0; | |
207 | } | |
208 | mc_groups_longs = new_longs; | |
209 | } | |
210 | } while (!fits); | |
2dbba6f7 | 211 | |
2a94fe48 JB |
212 | for (i = id; i < id + n_groups; i++) |
213 | set_bit(i, mc_groups); | |
214 | *first_id = id; | |
215 | return 0; | |
216 | } | |
217 | ||
218 | static struct genl_family genl_ctrl; | |
219 | ||
220 | static int genl_validate_assign_mc_groups(struct genl_family *family) | |
221 | { | |
222 | int first_id; | |
223 | int n_groups = family->n_mcgrps; | |
0f0e2159 | 224 | int err = 0, i; |
2a94fe48 JB |
225 | bool groups_allocated = false; |
226 | ||
227 | if (!n_groups) | |
228 | return 0; | |
229 | ||
230 | for (i = 0; i < n_groups; i++) { | |
231 | const struct genl_multicast_group *grp = &family->mcgrps[i]; | |
232 | ||
233 | if (WARN_ON(grp->name[0] == '\0')) | |
234 | return -EINVAL; | |
235 | if (WARN_ON(memchr(grp->name, '\0', GENL_NAMSIZ) == NULL)) | |
236 | return -EINVAL; | |
237 | } | |
2dbba6f7 | 238 | |
e5dcecba | 239 | /* special-case our own group and hacks */ |
2a94fe48 JB |
240 | if (family == &genl_ctrl) { |
241 | first_id = GENL_ID_CTRL; | |
242 | BUG_ON(n_groups != 1); | |
243 | } else if (strcmp(family->name, "NET_DM") == 0) { | |
244 | first_id = 1; | |
245 | BUG_ON(n_groups != 1); | |
5e53e689 | 246 | } else if (family->id == GENL_ID_VFS_DQUOT) { |
2a94fe48 JB |
247 | first_id = GENL_ID_VFS_DQUOT; |
248 | BUG_ON(n_groups != 1); | |
5e53e689 JB |
249 | } else if (family->id == GENL_ID_PMCRAID) { |
250 | first_id = GENL_ID_PMCRAID; | |
251 | BUG_ON(n_groups != 1); | |
2a94fe48 JB |
252 | } else { |
253 | groups_allocated = true; | |
254 | err = genl_allocate_reserve_groups(n_groups, &first_id); | |
255 | if (err) | |
256 | return err; | |
2dbba6f7 JB |
257 | } |
258 | ||
2a94fe48 JB |
259 | family->mcgrp_offset = first_id; |
260 | ||
261 | /* if still initializing, can't and don't need to to realloc bitmaps */ | |
262 | if (!init_net.genl_sock) | |
263 | return 0; | |
264 | ||
134e6375 JB |
265 | if (family->netnsok) { |
266 | struct net *net; | |
267 | ||
d136f1bd | 268 | netlink_table_grab(); |
134e6375 JB |
269 | rcu_read_lock(); |
270 | for_each_net_rcu(net) { | |
d136f1bd | 271 | err = __netlink_change_ngroups(net->genl_sock, |
134e6375 JB |
272 | mc_groups_longs * BITS_PER_LONG); |
273 | if (err) { | |
274 | /* | |
275 | * No need to roll back, can only fail if | |
276 | * memory allocation fails and then the | |
277 | * number of _possible_ groups has been | |
278 | * increased on some sockets which is ok. | |
279 | */ | |
2a94fe48 | 280 | break; |
134e6375 JB |
281 | } |
282 | } | |
283 | rcu_read_unlock(); | |
d136f1bd | 284 | netlink_table_ungrab(); |
134e6375 JB |
285 | } else { |
286 | err = netlink_change_ngroups(init_net.genl_sock, | |
287 | mc_groups_longs * BITS_PER_LONG); | |
134e6375 | 288 | } |
2dbba6f7 | 289 | |
2a94fe48 JB |
290 | if (groups_allocated && err) { |
291 | for (i = 0; i < family->n_mcgrps; i++) | |
292 | clear_bit(family->mcgrp_offset + i, mc_groups); | |
293 | } | |
2dbba6f7 | 294 | |
79d310d0 | 295 | return err; |
2dbba6f7 | 296 | } |
2dbba6f7 | 297 | |
2a94fe48 | 298 | static void genl_unregister_mc_groups(struct genl_family *family) |
79dc4386 | 299 | { |
134e6375 | 300 | struct net *net; |
2a94fe48 | 301 | int i; |
134e6375 | 302 | |
b8273570 | 303 | netlink_table_grab(); |
134e6375 | 304 | rcu_read_lock(); |
2a94fe48 JB |
305 | for_each_net_rcu(net) { |
306 | for (i = 0; i < family->n_mcgrps; i++) | |
307 | __netlink_clear_multicast_users( | |
308 | net->genl_sock, family->mcgrp_offset + i); | |
309 | } | |
134e6375 | 310 | rcu_read_unlock(); |
b8273570 | 311 | netlink_table_ungrab(); |
134e6375 | 312 | |
2a94fe48 JB |
313 | for (i = 0; i < family->n_mcgrps; i++) { |
314 | int grp_id = family->mcgrp_offset + i; | |
2dbba6f7 | 315 | |
2a94fe48 JB |
316 | if (grp_id != 1) |
317 | clear_bit(grp_id, mc_groups); | |
318 | genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, family, | |
319 | &family->mcgrps[i], grp_id); | |
320 | } | |
2dbba6f7 JB |
321 | } |
322 | ||
2f91abd4 | 323 | static int genl_validate_ops(const struct genl_family *family) |
482a8524 | 324 | { |
568508aa JB |
325 | const struct genl_ops *ops = family->ops; |
326 | unsigned int n_ops = family->n_ops; | |
d91824c0 JB |
327 | int i, j; |
328 | ||
568508aa JB |
329 | if (WARN_ON(n_ops && !ops)) |
330 | return -EINVAL; | |
331 | ||
332 | if (!n_ops) | |
333 | return 0; | |
334 | ||
d91824c0 JB |
335 | for (i = 0; i < n_ops; i++) { |
336 | if (ops[i].dumpit == NULL && ops[i].doit == NULL) | |
337 | return -EINVAL; | |
338 | for (j = i + 1; j < n_ops; j++) | |
339 | if (ops[i].cmd == ops[j].cmd) | |
340 | return -EINVAL; | |
482a8524 TG |
341 | } |
342 | ||
d91824c0 | 343 | return 0; |
482a8524 | 344 | } |
482a8524 TG |
345 | |
346 | /** | |
33c6b1f6 | 347 | * __genl_register_family - register a generic netlink family |
482a8524 TG |
348 | * @family: generic netlink family |
349 | * | |
350 | * Registers the specified family after validating it first. Only one | |
351 | * family may be registered with the same family name or identifier. | |
482a8524 | 352 | * |
568508aa JB |
353 | * The family's ops array must already be assigned, you can use the |
354 | * genl_register_family_with_ops() helper function. | |
355 | * | |
482a8524 TG |
356 | * Return 0 on success or a negative error code. |
357 | */ | |
33c6b1f6 | 358 | int __genl_register_family(struct genl_family *family) |
482a8524 | 359 | { |
a07ea4d9 | 360 | int err, i; |
482a8524 | 361 | |
568508aa JB |
362 | err = genl_validate_ops(family); |
363 | if (err) | |
364 | return err; | |
365 | ||
def31174 | 366 | genl_lock_all(); |
482a8524 TG |
367 | |
368 | if (genl_family_find_byname(family->name)) { | |
369 | err = -EEXIST; | |
370 | goto errout_locked; | |
371 | } | |
372 | ||
a07ea4d9 JB |
373 | if (family == &genl_ctrl) { |
374 | family->id = GENL_ID_CTRL; | |
375 | } else { | |
376 | u16 newid; | |
377 | ||
378 | /* this should be left zero in the struct */ | |
379 | WARN_ON(family->id); | |
380 | ||
381 | /* | |
382 | * Sadly, a few cases need to be special-cased | |
383 | * due to them having previously abused the API | |
384 | * and having used their family ID also as their | |
385 | * multicast group ID, so we use reserved IDs | |
386 | * for both to be sure we can do that mapping. | |
387 | */ | |
388 | if (strcmp(family->name, "pmcraid") == 0) | |
389 | newid = GENL_ID_PMCRAID; | |
390 | else if (strcmp(family->name, "VFS_DQUOT") == 0) | |
391 | newid = GENL_ID_VFS_DQUOT; | |
392 | else | |
393 | newid = genl_generate_id(); | |
482a8524 TG |
394 | |
395 | if (!newid) { | |
396 | err = -ENOMEM; | |
397 | goto errout_locked; | |
398 | } | |
399 | ||
400 | family->id = newid; | |
401 | } | |
402 | ||
def31174 | 403 | if (family->maxattr && !family->parallel_ops) { |
482a8524 TG |
404 | family->attrbuf = kmalloc((family->maxattr+1) * |
405 | sizeof(struct nlattr *), GFP_KERNEL); | |
406 | if (family->attrbuf == NULL) { | |
407 | err = -ENOMEM; | |
e200bd80 | 408 | goto errout_locked; |
482a8524 TG |
409 | } |
410 | } else | |
411 | family->attrbuf = NULL; | |
412 | ||
2a94fe48 JB |
413 | err = genl_validate_assign_mc_groups(family); |
414 | if (err) | |
415 | goto errout_locked; | |
416 | ||
482a8524 | 417 | list_add_tail(&family->family_list, genl_family_chain(family->id)); |
def31174 | 418 | genl_unlock_all(); |
482a8524 | 419 | |
2a94fe48 JB |
420 | /* send all events */ |
421 | genl_ctrl_event(CTRL_CMD_NEWFAMILY, family, NULL, 0); | |
422 | for (i = 0; i < family->n_mcgrps; i++) | |
423 | genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, family, | |
424 | &family->mcgrps[i], family->mcgrp_offset + i); | |
482a8524 TG |
425 | |
426 | return 0; | |
427 | ||
428 | errout_locked: | |
def31174 | 429 | genl_unlock_all(); |
482a8524 TG |
430 | return err; |
431 | } | |
33c6b1f6 | 432 | EXPORT_SYMBOL(__genl_register_family); |
482a8524 TG |
433 | |
434 | /** | |
435 | * genl_unregister_family - unregister generic netlink family | |
436 | * @family: generic netlink family | |
437 | * | |
438 | * Unregisters the specified family. | |
439 | * | |
440 | * Returns 0 on success or a negative error code. | |
441 | */ | |
442 | int genl_unregister_family(struct genl_family *family) | |
443 | { | |
444 | struct genl_family *rc; | |
445 | ||
def31174 | 446 | genl_lock_all(); |
482a8524 TG |
447 | |
448 | list_for_each_entry(rc, genl_family_chain(family->id), family_list) { | |
449 | if (family->id != rc->id || strcmp(rc->name, family->name)) | |
450 | continue; | |
451 | ||
ee1c2442 JB |
452 | genl_unregister_mc_groups(family); |
453 | ||
482a8524 | 454 | list_del(&rc->family_list); |
d91824c0 | 455 | family->n_ops = 0; |
ee1c2442 JB |
456 | up_write(&cb_lock); |
457 | wait_event(genl_sk_destructing_waitq, | |
458 | atomic_read(&genl_sk_destructing_cnt) == 0); | |
459 | genl_unlock(); | |
482a8524 | 460 | |
482a8524 | 461 | kfree(family->attrbuf); |
2a94fe48 | 462 | genl_ctrl_event(CTRL_CMD_DELFAMILY, family, NULL, 0); |
482a8524 TG |
463 | return 0; |
464 | } | |
465 | ||
def31174 | 466 | genl_unlock_all(); |
482a8524 TG |
467 | |
468 | return -ENOENT; | |
469 | } | |
416c2f9c | 470 | EXPORT_SYMBOL(genl_unregister_family); |
482a8524 | 471 | |
a46621a3 DV |
472 | /** |
473 | * genlmsg_put - Add generic netlink header to netlink message | |
474 | * @skb: socket buffer holding the message | |
15e47304 | 475 | * @portid: netlink portid the message is addressed to |
a46621a3 DV |
476 | * @seq: sequence number (usually the one of the sender) |
477 | * @family: generic netlink family | |
2c53040f | 478 | * @flags: netlink message flags |
a46621a3 DV |
479 | * @cmd: generic netlink command |
480 | * | |
481 | * Returns pointer to user specific header | |
482 | */ | |
15e47304 | 483 | void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, |
a46621a3 DV |
484 | struct genl_family *family, int flags, u8 cmd) |
485 | { | |
486 | struct nlmsghdr *nlh; | |
487 | struct genlmsghdr *hdr; | |
488 | ||
15e47304 | 489 | nlh = nlmsg_put(skb, portid, seq, family->id, GENL_HDRLEN + |
a46621a3 DV |
490 | family->hdrsize, flags); |
491 | if (nlh == NULL) | |
492 | return NULL; | |
493 | ||
494 | hdr = nlmsg_data(nlh); | |
495 | hdr->cmd = cmd; | |
496 | hdr->version = family->version; | |
497 | hdr->reserved = 0; | |
498 | ||
499 | return (char *) hdr + GENL_HDRLEN; | |
500 | } | |
501 | EXPORT_SYMBOL(genlmsg_put); | |
502 | ||
fc9e50f5 TH |
503 | static int genl_lock_start(struct netlink_callback *cb) |
504 | { | |
505 | /* our ops are always const - netlink API doesn't propagate that */ | |
506 | const struct genl_ops *ops = cb->data; | |
507 | int rc = 0; | |
508 | ||
509 | if (ops->start) { | |
510 | genl_lock(); | |
511 | rc = ops->start(cb); | |
512 | genl_unlock(); | |
513 | } | |
514 | return rc; | |
515 | } | |
516 | ||
9b96309c PS |
517 | static int genl_lock_dumpit(struct sk_buff *skb, struct netlink_callback *cb) |
518 | { | |
f84f771d JB |
519 | /* our ops are always const - netlink API doesn't propagate that */ |
520 | const struct genl_ops *ops = cb->data; | |
9b96309c PS |
521 | int rc; |
522 | ||
523 | genl_lock(); | |
524 | rc = ops->dumpit(skb, cb); | |
525 | genl_unlock(); | |
526 | return rc; | |
527 | } | |
528 | ||
529 | static int genl_lock_done(struct netlink_callback *cb) | |
530 | { | |
f84f771d JB |
531 | /* our ops are always const - netlink API doesn't propagate that */ |
532 | const struct genl_ops *ops = cb->data; | |
9b96309c PS |
533 | int rc = 0; |
534 | ||
535 | if (ops->done) { | |
536 | genl_lock(); | |
537 | rc = ops->done(cb); | |
538 | genl_unlock(); | |
539 | } | |
540 | return rc; | |
541 | } | |
542 | ||
def31174 PS |
543 | static int genl_family_rcv_msg(struct genl_family *family, |
544 | struct sk_buff *skb, | |
545 | struct nlmsghdr *nlh) | |
482a8524 | 546 | { |
f84f771d | 547 | const struct genl_ops *ops; |
134e6375 | 548 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
549 | struct genl_info info; |
550 | struct genlmsghdr *hdr = nlmsg_data(nlh); | |
def31174 | 551 | struct nlattr **attrbuf; |
1d00a4eb | 552 | int hdrlen, err; |
482a8524 | 553 | |
134e6375 JB |
554 | /* this family doesn't exist in this netns */ |
555 | if (!family->netnsok && !net_eq(net, &init_net)) | |
556 | return -ENOENT; | |
557 | ||
482a8524 TG |
558 | hdrlen = GENL_HDRLEN + family->hdrsize; |
559 | if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) | |
1d00a4eb | 560 | return -EINVAL; |
482a8524 TG |
561 | |
562 | ops = genl_get_cmd(hdr->cmd, family); | |
1d00a4eb TG |
563 | if (ops == NULL) |
564 | return -EOPNOTSUPP; | |
482a8524 | 565 | |
1d00a4eb | 566 | if ((ops->flags & GENL_ADMIN_PERM) && |
90f62cf3 | 567 | !netlink_capable(skb, CAP_NET_ADMIN)) |
1d00a4eb | 568 | return -EPERM; |
482a8524 | 569 | |
4a92602a TA |
570 | if ((ops->flags & GENL_UNS_ADMIN_PERM) && |
571 | !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) | |
572 | return -EPERM; | |
573 | ||
e1ee3673 | 574 | if ((nlh->nlmsg_flags & NLM_F_DUMP) == NLM_F_DUMP) { |
9b96309c | 575 | int rc; |
def31174 | 576 | |
1d00a4eb TG |
577 | if (ops->dumpit == NULL) |
578 | return -EOPNOTSUPP; | |
482a8524 | 579 | |
9b96309c PS |
580 | if (!family->parallel_ops) { |
581 | struct netlink_dump_control c = { | |
33c6b1f6 | 582 | .module = family->module, |
f84f771d JB |
583 | /* we have const, but the netlink API doesn't */ |
584 | .data = (void *)ops, | |
fc9e50f5 | 585 | .start = genl_lock_start, |
9b96309c PS |
586 | .dump = genl_lock_dumpit, |
587 | .done = genl_lock_done, | |
588 | }; | |
589 | ||
590 | genl_unlock(); | |
33c6b1f6 | 591 | rc = __netlink_dump_start(net->genl_sock, skb, nlh, &c); |
9b96309c PS |
592 | genl_lock(); |
593 | ||
594 | } else { | |
595 | struct netlink_dump_control c = { | |
33c6b1f6 | 596 | .module = family->module, |
fc9e50f5 | 597 | .start = ops->start, |
9b96309c PS |
598 | .dump = ops->dumpit, |
599 | .done = ops->done, | |
600 | }; | |
601 | ||
33c6b1f6 | 602 | rc = __netlink_dump_start(net->genl_sock, skb, nlh, &c); |
9b96309c PS |
603 | } |
604 | ||
605 | return rc; | |
482a8524 TG |
606 | } |
607 | ||
1d00a4eb TG |
608 | if (ops->doit == NULL) |
609 | return -EOPNOTSUPP; | |
482a8524 | 610 | |
def31174 PS |
611 | if (family->maxattr && family->parallel_ops) { |
612 | attrbuf = kmalloc((family->maxattr+1) * | |
613 | sizeof(struct nlattr *), GFP_KERNEL); | |
614 | if (attrbuf == NULL) | |
615 | return -ENOMEM; | |
616 | } else | |
617 | attrbuf = family->attrbuf; | |
618 | ||
619 | if (attrbuf) { | |
620 | err = nlmsg_parse(nlh, hdrlen, attrbuf, family->maxattr, | |
482a8524 TG |
621 | ops->policy); |
622 | if (err < 0) | |
50754d21 | 623 | goto out; |
482a8524 TG |
624 | } |
625 | ||
626 | info.snd_seq = nlh->nlmsg_seq; | |
15e47304 | 627 | info.snd_portid = NETLINK_CB(skb).portid; |
482a8524 TG |
628 | info.nlhdr = nlh; |
629 | info.genlhdr = nlmsg_data(nlh); | |
630 | info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN; | |
def31174 | 631 | info.attrs = attrbuf; |
134e6375 | 632 | genl_info_net_set(&info, net); |
ff4c92d8 | 633 | memset(&info.user_ptr, 0, sizeof(info.user_ptr)); |
482a8524 | 634 | |
ff4c92d8 JB |
635 | if (family->pre_doit) { |
636 | err = family->pre_doit(ops, skb, &info); | |
637 | if (err) | |
50754d21 | 638 | goto out; |
ff4c92d8 JB |
639 | } |
640 | ||
641 | err = ops->doit(skb, &info); | |
642 | ||
643 | if (family->post_doit) | |
644 | family->post_doit(ops, skb, &info); | |
645 | ||
50754d21 | 646 | out: |
def31174 PS |
647 | if (family->parallel_ops) |
648 | kfree(attrbuf); | |
649 | ||
650 | return err; | |
651 | } | |
652 | ||
653 | static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) | |
654 | { | |
655 | struct genl_family *family; | |
656 | int err; | |
657 | ||
658 | family = genl_family_find_byid(nlh->nlmsg_type); | |
659 | if (family == NULL) | |
660 | return -ENOENT; | |
661 | ||
662 | if (!family->parallel_ops) | |
663 | genl_lock(); | |
664 | ||
665 | err = genl_family_rcv_msg(family, skb, nlh); | |
666 | ||
667 | if (!family->parallel_ops) | |
668 | genl_unlock(); | |
669 | ||
ff4c92d8 | 670 | return err; |
482a8524 TG |
671 | } |
672 | ||
cd40b7d3 | 673 | static void genl_rcv(struct sk_buff *skb) |
482a8524 | 674 | { |
def31174 | 675 | down_read(&cb_lock); |
cd40b7d3 | 676 | netlink_rcv_skb(skb, &genl_rcv_msg); |
def31174 | 677 | up_read(&cb_lock); |
482a8524 TG |
678 | } |
679 | ||
680 | /************************************************************************** | |
681 | * Controller | |
682 | **************************************************************************/ | |
683 | ||
17c157c8 TG |
684 | static struct genl_family genl_ctrl = { |
685 | .id = GENL_ID_CTRL, | |
686 | .name = "nlctrl", | |
334c29a6 | 687 | .version = 0x2, |
17c157c8 | 688 | .maxattr = CTRL_ATTR_MAX, |
134e6375 | 689 | .netnsok = true, |
17c157c8 TG |
690 | }; |
691 | ||
15e47304 | 692 | static int ctrl_fill_info(struct genl_family *family, u32 portid, u32 seq, |
482a8524 TG |
693 | u32 flags, struct sk_buff *skb, u8 cmd) |
694 | { | |
695 | void *hdr; | |
696 | ||
15e47304 | 697 | hdr = genlmsg_put(skb, portid, seq, &genl_ctrl, flags, cmd); |
482a8524 TG |
698 | if (hdr == NULL) |
699 | return -1; | |
700 | ||
444653f6 DM |
701 | if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, family->name) || |
702 | nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, family->id) || | |
703 | nla_put_u32(skb, CTRL_ATTR_VERSION, family->version) || | |
704 | nla_put_u32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize) || | |
705 | nla_put_u32(skb, CTRL_ATTR_MAXATTR, family->maxattr)) | |
706 | goto nla_put_failure; | |
eb328111 | 707 | |
d91824c0 | 708 | if (family->n_ops) { |
e94ef682 | 709 | struct nlattr *nla_ops; |
d91824c0 | 710 | int i; |
eb328111 | 711 | |
e94ef682 TG |
712 | nla_ops = nla_nest_start(skb, CTRL_ATTR_OPS); |
713 | if (nla_ops == NULL) | |
eb328111 TG |
714 | goto nla_put_failure; |
715 | ||
d91824c0 | 716 | for (i = 0; i < family->n_ops; i++) { |
e94ef682 | 717 | struct nlattr *nest; |
f84f771d | 718 | const struct genl_ops *ops = &family->ops[i]; |
029b234f | 719 | u32 op_flags = ops->flags; |
f84f771d JB |
720 | |
721 | if (ops->dumpit) | |
029b234f | 722 | op_flags |= GENL_CMD_CAP_DUMP; |
f84f771d | 723 | if (ops->doit) |
029b234f | 724 | op_flags |= GENL_CMD_CAP_DO; |
f84f771d | 725 | if (ops->policy) |
029b234f | 726 | op_flags |= GENL_CMD_CAP_HASPOL; |
eb328111 | 727 | |
d91824c0 | 728 | nest = nla_nest_start(skb, i + 1); |
e94ef682 TG |
729 | if (nest == NULL) |
730 | goto nla_put_failure; | |
eb328111 | 731 | |
444653f6 | 732 | if (nla_put_u32(skb, CTRL_ATTR_OP_ID, ops->cmd) || |
029b234f | 733 | nla_put_u32(skb, CTRL_ATTR_OP_FLAGS, op_flags)) |
444653f6 | 734 | goto nla_put_failure; |
eb328111 | 735 | |
e94ef682 TG |
736 | nla_nest_end(skb, nest); |
737 | } | |
738 | ||
739 | nla_nest_end(skb, nla_ops); | |
740 | } | |
482a8524 | 741 | |
2a94fe48 | 742 | if (family->n_mcgrps) { |
2dbba6f7 | 743 | struct nlattr *nla_grps; |
2a94fe48 | 744 | int i; |
2dbba6f7 JB |
745 | |
746 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
747 | if (nla_grps == NULL) | |
748 | goto nla_put_failure; | |
749 | ||
2a94fe48 | 750 | for (i = 0; i < family->n_mcgrps; i++) { |
2dbba6f7 | 751 | struct nlattr *nest; |
2a94fe48 | 752 | const struct genl_multicast_group *grp; |
2dbba6f7 | 753 | |
2a94fe48 JB |
754 | grp = &family->mcgrps[i]; |
755 | ||
756 | nest = nla_nest_start(skb, i + 1); | |
2dbba6f7 JB |
757 | if (nest == NULL) |
758 | goto nla_put_failure; | |
759 | ||
2a94fe48 JB |
760 | if (nla_put_u32(skb, CTRL_ATTR_MCAST_GRP_ID, |
761 | family->mcgrp_offset + i) || | |
444653f6 DM |
762 | nla_put_string(skb, CTRL_ATTR_MCAST_GRP_NAME, |
763 | grp->name)) | |
764 | goto nla_put_failure; | |
2dbba6f7 JB |
765 | |
766 | nla_nest_end(skb, nest); | |
767 | } | |
768 | nla_nest_end(skb, nla_grps); | |
769 | } | |
770 | ||
053c095a JB |
771 | genlmsg_end(skb, hdr); |
772 | return 0; | |
2dbba6f7 JB |
773 | |
774 | nla_put_failure: | |
bc3ed28c TG |
775 | genlmsg_cancel(skb, hdr); |
776 | return -EMSGSIZE; | |
2dbba6f7 JB |
777 | } |
778 | ||
c2ebb908 | 779 | static int ctrl_fill_mcgrp_info(struct genl_family *family, |
2a94fe48 JB |
780 | const struct genl_multicast_group *grp, |
781 | int grp_id, u32 portid, u32 seq, u32 flags, | |
782 | struct sk_buff *skb, u8 cmd) | |
2dbba6f7 JB |
783 | { |
784 | void *hdr; | |
785 | struct nlattr *nla_grps; | |
786 | struct nlattr *nest; | |
787 | ||
15e47304 | 788 | hdr = genlmsg_put(skb, portid, seq, &genl_ctrl, flags, cmd); |
2dbba6f7 JB |
789 | if (hdr == NULL) |
790 | return -1; | |
791 | ||
c2ebb908 JB |
792 | if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, family->name) || |
793 | nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, family->id)) | |
444653f6 | 794 | goto nla_put_failure; |
2dbba6f7 JB |
795 | |
796 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
797 | if (nla_grps == NULL) | |
798 | goto nla_put_failure; | |
799 | ||
800 | nest = nla_nest_start(skb, 1); | |
801 | if (nest == NULL) | |
802 | goto nla_put_failure; | |
803 | ||
2a94fe48 | 804 | if (nla_put_u32(skb, CTRL_ATTR_MCAST_GRP_ID, grp_id) || |
444653f6 DM |
805 | nla_put_string(skb, CTRL_ATTR_MCAST_GRP_NAME, |
806 | grp->name)) | |
807 | goto nla_put_failure; | |
2dbba6f7 JB |
808 | |
809 | nla_nest_end(skb, nest); | |
810 | nla_nest_end(skb, nla_grps); | |
811 | ||
053c095a JB |
812 | genlmsg_end(skb, hdr); |
813 | return 0; | |
482a8524 TG |
814 | |
815 | nla_put_failure: | |
bc3ed28c TG |
816 | genlmsg_cancel(skb, hdr); |
817 | return -EMSGSIZE; | |
482a8524 TG |
818 | } |
819 | ||
820 | static int ctrl_dumpfamily(struct sk_buff *skb, struct netlink_callback *cb) | |
821 | { | |
822 | ||
823 | int i, n = 0; | |
824 | struct genl_family *rt; | |
134e6375 | 825 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
826 | int chains_to_skip = cb->args[0]; |
827 | int fams_to_skip = cb->args[1]; | |
828 | ||
e1d5a010 | 829 | for (i = chains_to_skip; i < GENL_FAM_TAB_SIZE; i++) { |
482a8524 TG |
830 | n = 0; |
831 | list_for_each_entry(rt, genl_family_chain(i), family_list) { | |
134e6375 JB |
832 | if (!rt->netnsok && !net_eq(net, &init_net)) |
833 | continue; | |
482a8524 TG |
834 | if (++n < fams_to_skip) |
835 | continue; | |
15e47304 | 836 | if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).portid, |
482a8524 TG |
837 | cb->nlh->nlmsg_seq, NLM_F_MULTI, |
838 | skb, CTRL_CMD_NEWFAMILY) < 0) | |
839 | goto errout; | |
840 | } | |
841 | ||
842 | fams_to_skip = 0; | |
843 | } | |
844 | ||
845 | errout: | |
846 | cb->args[0] = i; | |
847 | cb->args[1] = n; | |
848 | ||
849 | return skb->len; | |
850 | } | |
851 | ||
2dbba6f7 | 852 | static struct sk_buff *ctrl_build_family_msg(struct genl_family *family, |
15e47304 | 853 | u32 portid, int seq, u8 cmd) |
482a8524 TG |
854 | { |
855 | struct sk_buff *skb; | |
856 | int err; | |
857 | ||
339bf98f | 858 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); |
482a8524 TG |
859 | if (skb == NULL) |
860 | return ERR_PTR(-ENOBUFS); | |
861 | ||
15e47304 | 862 | err = ctrl_fill_info(family, portid, seq, 0, skb, cmd); |
482a8524 TG |
863 | if (err < 0) { |
864 | nlmsg_free(skb); | |
865 | return ERR_PTR(err); | |
866 | } | |
867 | ||
868 | return skb; | |
869 | } | |
870 | ||
2a94fe48 JB |
871 | static struct sk_buff * |
872 | ctrl_build_mcgrp_msg(struct genl_family *family, | |
873 | const struct genl_multicast_group *grp, | |
874 | int grp_id, u32 portid, int seq, u8 cmd) | |
2dbba6f7 JB |
875 | { |
876 | struct sk_buff *skb; | |
877 | int err; | |
878 | ||
879 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); | |
880 | if (skb == NULL) | |
881 | return ERR_PTR(-ENOBUFS); | |
882 | ||
2a94fe48 JB |
883 | err = ctrl_fill_mcgrp_info(family, grp, grp_id, portid, |
884 | seq, 0, skb, cmd); | |
2dbba6f7 JB |
885 | if (err < 0) { |
886 | nlmsg_free(skb); | |
887 | return ERR_PTR(err); | |
888 | } | |
889 | ||
890 | return skb; | |
891 | } | |
892 | ||
ef7c79ed | 893 | static const struct nla_policy ctrl_policy[CTRL_ATTR_MAX+1] = { |
482a8524 | 894 | [CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 }, |
5176f91e TG |
895 | [CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING, |
896 | .len = GENL_NAMSIZ - 1 }, | |
482a8524 TG |
897 | }; |
898 | ||
899 | static int ctrl_getfamily(struct sk_buff *skb, struct genl_info *info) | |
900 | { | |
901 | struct sk_buff *msg; | |
902 | struct genl_family *res = NULL; | |
903 | int err = -EINVAL; | |
904 | ||
905 | if (info->attrs[CTRL_ATTR_FAMILY_ID]) { | |
906 | u16 id = nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]); | |
907 | res = genl_family_find_byid(id); | |
134e6375 | 908 | err = -ENOENT; |
482a8524 TG |
909 | } |
910 | ||
911 | if (info->attrs[CTRL_ATTR_FAMILY_NAME]) { | |
5176f91e | 912 | char *name; |
482a8524 | 913 | |
5176f91e | 914 | name = nla_data(info->attrs[CTRL_ATTR_FAMILY_NAME]); |
482a8524 | 915 | res = genl_family_find_byname(name); |
fa843095 SH |
916 | #ifdef CONFIG_MODULES |
917 | if (res == NULL) { | |
918 | genl_unlock(); | |
c74f2b26 | 919 | up_read(&cb_lock); |
e9412c37 | 920 | request_module("net-pf-%d-proto-%d-family-%s", |
fa843095 | 921 | PF_NETLINK, NETLINK_GENERIC, name); |
c74f2b26 | 922 | down_read(&cb_lock); |
fa843095 SH |
923 | genl_lock(); |
924 | res = genl_family_find_byname(name); | |
925 | } | |
926 | #endif | |
134e6375 | 927 | err = -ENOENT; |
482a8524 TG |
928 | } |
929 | ||
134e6375 JB |
930 | if (res == NULL) |
931 | return err; | |
932 | ||
933 | if (!res->netnsok && !net_eq(genl_info_net(info), &init_net)) { | |
934 | /* family doesn't exist here */ | |
935 | return -ENOENT; | |
482a8524 TG |
936 | } |
937 | ||
15e47304 | 938 | msg = ctrl_build_family_msg(res, info->snd_portid, info->snd_seq, |
2dbba6f7 | 939 | CTRL_CMD_NEWFAMILY); |
134e6375 JB |
940 | if (IS_ERR(msg)) |
941 | return PTR_ERR(msg); | |
482a8524 | 942 | |
134e6375 | 943 | return genlmsg_reply(msg, info); |
482a8524 TG |
944 | } |
945 | ||
c2ebb908 | 946 | static int genl_ctrl_event(int event, struct genl_family *family, |
2a94fe48 JB |
947 | const struct genl_multicast_group *grp, |
948 | int grp_id) | |
482a8524 TG |
949 | { |
950 | struct sk_buff *msg; | |
951 | ||
134e6375 JB |
952 | /* genl is still initialising */ |
953 | if (!init_net.genl_sock) | |
482a8524 TG |
954 | return 0; |
955 | ||
956 | switch (event) { | |
957 | case CTRL_CMD_NEWFAMILY: | |
958 | case CTRL_CMD_DELFAMILY: | |
c2ebb908 | 959 | WARN_ON(grp); |
134e6375 | 960 | msg = ctrl_build_family_msg(family, 0, 0, event); |
2dbba6f7 JB |
961 | break; |
962 | case CTRL_CMD_NEWMCAST_GRP: | |
963 | case CTRL_CMD_DELMCAST_GRP: | |
c2ebb908 | 964 | BUG_ON(!grp); |
2a94fe48 | 965 | msg = ctrl_build_mcgrp_msg(family, grp, grp_id, 0, 0, event); |
482a8524 | 966 | break; |
134e6375 JB |
967 | default: |
968 | return -EINVAL; | |
969 | } | |
970 | ||
971 | if (IS_ERR(msg)) | |
972 | return PTR_ERR(msg); | |
973 | ||
974 | if (!family->netnsok) { | |
68eb5503 | 975 | genlmsg_multicast_netns(&genl_ctrl, &init_net, msg, 0, |
2a94fe48 | 976 | 0, GFP_KERNEL); |
134e6375 JB |
977 | } else { |
978 | rcu_read_lock(); | |
68eb5503 | 979 | genlmsg_multicast_allns(&genl_ctrl, msg, 0, |
2a94fe48 | 980 | 0, GFP_ATOMIC); |
134e6375 | 981 | rcu_read_unlock(); |
482a8524 TG |
982 | } |
983 | ||
984 | return 0; | |
985 | } | |
986 | ||
12d8de6d | 987 | static const struct genl_ops genl_ctrl_ops[] = { |
c53ed742 JB |
988 | { |
989 | .cmd = CTRL_CMD_GETFAMILY, | |
990 | .doit = ctrl_getfamily, | |
991 | .dumpit = ctrl_dumpfamily, | |
992 | .policy = ctrl_policy, | |
993 | }, | |
482a8524 TG |
994 | }; |
995 | ||
12d8de6d | 996 | static const struct genl_multicast_group genl_ctrl_groups[] = { |
2a94fe48 | 997 | { .name = "notify", }, |
2dbba6f7 JB |
998 | }; |
999 | ||
023e2cfa | 1000 | static int genl_bind(struct net *net, int group) |
c380d9a7 | 1001 | { |
5ad63005 | 1002 | int i, err = -ENOENT; |
c380d9a7 JB |
1003 | |
1004 | down_read(&cb_lock); | |
1005 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) { | |
1006 | struct genl_family *f; | |
1007 | ||
1008 | list_for_each_entry(f, genl_family_chain(i), family_list) { | |
1009 | if (group >= f->mcgrp_offset && | |
1010 | group < f->mcgrp_offset + f->n_mcgrps) { | |
1011 | int fam_grp = group - f->mcgrp_offset; | |
1012 | ||
023e2cfa JB |
1013 | if (!f->netnsok && net != &init_net) |
1014 | err = -ENOENT; | |
1015 | else if (f->mcast_bind) | |
1016 | err = f->mcast_bind(net, fam_grp); | |
c380d9a7 JB |
1017 | else |
1018 | err = 0; | |
c380d9a7 JB |
1019 | break; |
1020 | } | |
1021 | } | |
1022 | } | |
1023 | up_read(&cb_lock); | |
1024 | ||
c380d9a7 JB |
1025 | return err; |
1026 | } | |
1027 | ||
023e2cfa | 1028 | static void genl_unbind(struct net *net, int group) |
c380d9a7 JB |
1029 | { |
1030 | int i; | |
c380d9a7 JB |
1031 | |
1032 | down_read(&cb_lock); | |
1033 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) { | |
1034 | struct genl_family *f; | |
1035 | ||
1036 | list_for_each_entry(f, genl_family_chain(i), family_list) { | |
1037 | if (group >= f->mcgrp_offset && | |
1038 | group < f->mcgrp_offset + f->n_mcgrps) { | |
1039 | int fam_grp = group - f->mcgrp_offset; | |
1040 | ||
1041 | if (f->mcast_unbind) | |
023e2cfa | 1042 | f->mcast_unbind(net, fam_grp); |
c380d9a7 JB |
1043 | break; |
1044 | } | |
1045 | } | |
1046 | } | |
1047 | up_read(&cb_lock); | |
c380d9a7 JB |
1048 | } |
1049 | ||
134e6375 JB |
1050 | static int __net_init genl_pernet_init(struct net *net) |
1051 | { | |
a31f2d17 PNA |
1052 | struct netlink_kernel_cfg cfg = { |
1053 | .input = genl_rcv, | |
9785e10a | 1054 | .flags = NL_CFG_F_NONROOT_RECV, |
c380d9a7 JB |
1055 | .bind = genl_bind, |
1056 | .unbind = genl_unbind, | |
a31f2d17 PNA |
1057 | }; |
1058 | ||
134e6375 | 1059 | /* we'll bump the group number right afterwards */ |
9f00d977 | 1060 | net->genl_sock = netlink_kernel_create(net, NETLINK_GENERIC, &cfg); |
134e6375 JB |
1061 | |
1062 | if (!net->genl_sock && net_eq(net, &init_net)) | |
1063 | panic("GENL: Cannot initialize generic netlink\n"); | |
1064 | ||
1065 | if (!net->genl_sock) | |
1066 | return -ENOMEM; | |
1067 | ||
1068 | return 0; | |
1069 | } | |
1070 | ||
1071 | static void __net_exit genl_pernet_exit(struct net *net) | |
1072 | { | |
1073 | netlink_kernel_release(net->genl_sock); | |
1074 | net->genl_sock = NULL; | |
1075 | } | |
1076 | ||
1077 | static struct pernet_operations genl_pernet_ops = { | |
1078 | .init = genl_pernet_init, | |
1079 | .exit = genl_pernet_exit, | |
1080 | }; | |
1081 | ||
482a8524 TG |
1082 | static int __init genl_init(void) |
1083 | { | |
1084 | int i, err; | |
1085 | ||
1086 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) | |
1087 | INIT_LIST_HEAD(&family_ht[i]); | |
1088 | ||
2a94fe48 JB |
1089 | err = genl_register_family_with_ops_groups(&genl_ctrl, genl_ctrl_ops, |
1090 | genl_ctrl_groups); | |
482a8524 | 1091 | if (err < 0) |
134e6375 | 1092 | goto problem; |
482a8524 | 1093 | |
134e6375 JB |
1094 | err = register_pernet_subsys(&genl_pernet_ops); |
1095 | if (err) | |
1096 | goto problem; | |
482a8524 TG |
1097 | |
1098 | return 0; | |
1099 | ||
134e6375 | 1100 | problem: |
482a8524 | 1101 | panic("GENL: Cannot register controller: %d\n", err); |
482a8524 TG |
1102 | } |
1103 | ||
1104 | subsys_initcall(genl_init); | |
1105 | ||
c90c39da JB |
1106 | /** |
1107 | * genl_family_attrbuf - return family's attrbuf | |
1108 | * @family: the family | |
1109 | * | |
1110 | * Return the family's attrbuf, while validating that it's | |
1111 | * actually valid to access it. | |
1112 | * | |
1113 | * You cannot use this function with a family that has parallel_ops | |
1114 | * and you can only use it within (pre/post) doit/dumpit callbacks. | |
1115 | */ | |
1116 | struct nlattr **genl_family_attrbuf(struct genl_family *family) | |
1117 | { | |
1118 | if (!WARN_ON(family->parallel_ops)) | |
1119 | lockdep_assert_held(&genl_mutex); | |
1120 | ||
1121 | return family->attrbuf; | |
1122 | } | |
1123 | EXPORT_SYMBOL(genl_family_attrbuf); | |
1124 | ||
15e47304 | 1125 | static int genlmsg_mcast(struct sk_buff *skb, u32 portid, unsigned long group, |
134e6375 JB |
1126 | gfp_t flags) |
1127 | { | |
1128 | struct sk_buff *tmp; | |
1129 | struct net *net, *prev = NULL; | |
1130 | int err; | |
1131 | ||
1132 | for_each_net_rcu(net) { | |
1133 | if (prev) { | |
1134 | tmp = skb_clone(skb, flags); | |
1135 | if (!tmp) { | |
1136 | err = -ENOMEM; | |
1137 | goto error; | |
1138 | } | |
1139 | err = nlmsg_multicast(prev->genl_sock, tmp, | |
15e47304 | 1140 | portid, group, flags); |
134e6375 JB |
1141 | if (err) |
1142 | goto error; | |
1143 | } | |
1144 | ||
1145 | prev = net; | |
1146 | } | |
1147 | ||
15e47304 | 1148 | return nlmsg_multicast(prev->genl_sock, skb, portid, group, flags); |
134e6375 JB |
1149 | error: |
1150 | kfree_skb(skb); | |
1151 | return err; | |
1152 | } | |
1153 | ||
68eb5503 JB |
1154 | int genlmsg_multicast_allns(struct genl_family *family, struct sk_buff *skb, |
1155 | u32 portid, unsigned int group, gfp_t flags) | |
134e6375 | 1156 | { |
220815a9 | 1157 | if (WARN_ON_ONCE(group >= family->n_mcgrps)) |
2a94fe48 JB |
1158 | return -EINVAL; |
1159 | group = family->mcgrp_offset + group; | |
15e47304 | 1160 | return genlmsg_mcast(skb, portid, group, flags); |
134e6375 JB |
1161 | } |
1162 | EXPORT_SYMBOL(genlmsg_multicast_allns); | |
263ba61d | 1163 | |
92c14d9b JB |
1164 | void genl_notify(struct genl_family *family, struct sk_buff *skb, |
1165 | struct genl_info *info, u32 group, gfp_t flags) | |
263ba61d | 1166 | { |
92c14d9b | 1167 | struct net *net = genl_info_net(info); |
263ba61d PS |
1168 | struct sock *sk = net->genl_sock; |
1169 | int report = 0; | |
1170 | ||
92c14d9b JB |
1171 | if (info->nlhdr) |
1172 | report = nlmsg_report(info->nlhdr); | |
263ba61d | 1173 | |
220815a9 | 1174 | if (WARN_ON_ONCE(group >= family->n_mcgrps)) |
2a94fe48 JB |
1175 | return; |
1176 | group = family->mcgrp_offset + group; | |
92c14d9b | 1177 | nlmsg_notify(sk, skb, info->snd_portid, group, report, flags); |
263ba61d PS |
1178 | } |
1179 | EXPORT_SYMBOL(genl_notify); |