Commit | Line | Data |
---|---|---|
482a8524 TG |
1 | /* |
2 | * NETLINK Generic Netlink Family | |
3 | * | |
4 | * Authors: Jamal Hadi Salim | |
5 | * Thomas Graf <tgraf@suug.ch> | |
2dbba6f7 | 6 | * Johannes Berg <johannes@sipsolutions.net> |
482a8524 TG |
7 | */ |
8 | ||
482a8524 TG |
9 | #include <linux/module.h> |
10 | #include <linux/kernel.h> | |
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 | |
f408e0ce | 26 | void genl_lock(void) |
482a8524 | 27 | { |
14cc3e2b | 28 | mutex_lock(&genl_mutex); |
482a8524 | 29 | } |
f408e0ce | 30 | EXPORT_SYMBOL(genl_lock); |
482a8524 | 31 | |
f408e0ce | 32 | void genl_unlock(void) |
482a8524 | 33 | { |
14cc3e2b | 34 | mutex_unlock(&genl_mutex); |
482a8524 | 35 | } |
f408e0ce | 36 | EXPORT_SYMBOL(genl_unlock); |
482a8524 | 37 | |
320f5ea0 | 38 | #ifdef CONFIG_LOCKDEP |
86b1309c PS |
39 | int lockdep_genl_is_held(void) |
40 | { | |
41 | return lockdep_is_held(&genl_mutex); | |
42 | } | |
43 | EXPORT_SYMBOL(lockdep_genl_is_held); | |
44 | #endif | |
45 | ||
def31174 PS |
46 | static void genl_lock_all(void) |
47 | { | |
48 | down_write(&cb_lock); | |
49 | genl_lock(); | |
50 | } | |
51 | ||
52 | static void genl_unlock_all(void) | |
53 | { | |
54 | genl_unlock(); | |
55 | up_write(&cb_lock); | |
56 | } | |
57 | ||
482a8524 TG |
58 | #define GENL_FAM_TAB_SIZE 16 |
59 | #define GENL_FAM_TAB_MASK (GENL_FAM_TAB_SIZE - 1) | |
60 | ||
61 | static struct list_head family_ht[GENL_FAM_TAB_SIZE]; | |
2dbba6f7 JB |
62 | /* |
63 | * Bitmap of multicast groups that are currently in use. | |
64 | * | |
65 | * To avoid an allocation at boot of just one unsigned long, | |
66 | * declare it global instead. | |
67 | * Bit 0 is marked as already used since group 0 is invalid. | |
e5dcecba JB |
68 | * Bit 1 is marked as already used since the drop-monitor code |
69 | * abuses the API and thinks it can statically use group 1. | |
70 | * That group will typically conflict with other groups that | |
71 | * any proper users use. | |
2ecf7536 JB |
72 | * Bit 17 is marked as already used since the VFS quota code |
73 | * also abused this API and relied on family == group ID, we | |
74 | * cater to that by giving it a static family and group ID. | |
2dbba6f7 | 75 | */ |
2ecf7536 | 76 | static unsigned long mc_group_start = 0x3 | BIT(GENL_ID_VFS_DQUOT); |
2dbba6f7 JB |
77 | static unsigned long *mc_groups = &mc_group_start; |
78 | static unsigned long mc_groups_longs = 1; | |
482a8524 TG |
79 | |
80 | static int genl_ctrl_event(int event, void *data); | |
81 | ||
82 | static inline unsigned int genl_family_hash(unsigned int id) | |
83 | { | |
84 | return id & GENL_FAM_TAB_MASK; | |
85 | } | |
86 | ||
87 | static inline struct list_head *genl_family_chain(unsigned int id) | |
88 | { | |
89 | return &family_ht[genl_family_hash(id)]; | |
90 | } | |
91 | ||
92 | static struct genl_family *genl_family_find_byid(unsigned int id) | |
93 | { | |
94 | struct genl_family *f; | |
95 | ||
96 | list_for_each_entry(f, genl_family_chain(id), family_list) | |
97 | if (f->id == id) | |
98 | return f; | |
99 | ||
100 | return NULL; | |
101 | } | |
102 | ||
103 | static struct genl_family *genl_family_find_byname(char *name) | |
104 | { | |
105 | struct genl_family *f; | |
106 | int i; | |
107 | ||
108 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) | |
109 | list_for_each_entry(f, genl_family_chain(i), family_list) | |
110 | if (strcmp(f->name, name) == 0) | |
111 | return f; | |
112 | ||
113 | return NULL; | |
114 | } | |
115 | ||
f84f771d | 116 | static const struct genl_ops *genl_get_cmd(u8 cmd, struct genl_family *family) |
482a8524 | 117 | { |
d91824c0 | 118 | int i; |
482a8524 | 119 | |
d91824c0 JB |
120 | for (i = 0; i < family->n_ops; i++) |
121 | if (family->ops[i].cmd == cmd) | |
122 | return &family->ops[i]; | |
482a8524 TG |
123 | |
124 | return NULL; | |
125 | } | |
126 | ||
127 | /* Of course we are going to have problems once we hit | |
128 | * 2^16 alive types, but that can only happen by year 2K | |
129 | */ | |
b57ef81f | 130 | static u16 genl_generate_id(void) |
482a8524 | 131 | { |
988ade6b KK |
132 | static u16 id_gen_idx = GENL_MIN_ID; |
133 | int i; | |
482a8524 | 134 | |
988ade6b | 135 | for (i = 0; i <= GENL_MAX_ID - GENL_MIN_ID; i++) { |
2ecf7536 JB |
136 | if (id_gen_idx != GENL_ID_VFS_DQUOT && |
137 | !genl_family_find_byid(id_gen_idx)) | |
988ade6b KK |
138 | return id_gen_idx; |
139 | if (++id_gen_idx > GENL_MAX_ID) | |
482a8524 | 140 | id_gen_idx = GENL_MIN_ID; |
988ade6b | 141 | } |
482a8524 | 142 | |
988ade6b | 143 | return 0; |
482a8524 TG |
144 | } |
145 | ||
2dbba6f7 JB |
146 | static struct genl_multicast_group notify_grp; |
147 | ||
148 | /** | |
149 | * genl_register_mc_group - register a multicast group | |
150 | * | |
151 | * Registers the specified multicast group and notifies userspace | |
152 | * about the new group. | |
153 | * | |
154 | * Returns 0 on success or a negative error code. | |
155 | * | |
156 | * @family: The generic netlink family the group shall be registered for. | |
157 | * @grp: The group to register, must have a name. | |
158 | */ | |
159 | int genl_register_mc_group(struct genl_family *family, | |
160 | struct genl_multicast_group *grp) | |
161 | { | |
162 | int id; | |
163 | unsigned long *new_groups; | |
b1f57195 | 164 | int err = 0; |
2dbba6f7 JB |
165 | |
166 | BUG_ON(grp->name[0] == '\0'); | |
f1e79e20 | 167 | BUG_ON(memchr(grp->name, '\0', GENL_NAMSIZ) == NULL); |
2dbba6f7 | 168 | |
def31174 | 169 | genl_lock_all(); |
2dbba6f7 | 170 | |
e5dcecba | 171 | /* special-case our own group and hacks */ |
2dbba6f7 JB |
172 | if (grp == ¬ify_grp) |
173 | id = GENL_ID_CTRL; | |
e5dcecba JB |
174 | else if (strcmp(family->name, "NET_DM") == 0) |
175 | id = 1; | |
2ecf7536 JB |
176 | else if (strcmp(family->name, "VFS_DQUOT") == 0) |
177 | id = GENL_ID_VFS_DQUOT; | |
2dbba6f7 JB |
178 | else |
179 | id = find_first_zero_bit(mc_groups, | |
180 | mc_groups_longs * BITS_PER_LONG); | |
181 | ||
182 | ||
183 | if (id >= mc_groups_longs * BITS_PER_LONG) { | |
184 | size_t nlen = (mc_groups_longs + 1) * sizeof(unsigned long); | |
185 | ||
186 | if (mc_groups == &mc_group_start) { | |
187 | new_groups = kzalloc(nlen, GFP_KERNEL); | |
188 | if (!new_groups) { | |
189 | err = -ENOMEM; | |
190 | goto out; | |
191 | } | |
192 | mc_groups = new_groups; | |
193 | *mc_groups = mc_group_start; | |
194 | } else { | |
195 | new_groups = krealloc(mc_groups, nlen, GFP_KERNEL); | |
196 | if (!new_groups) { | |
197 | err = -ENOMEM; | |
198 | goto out; | |
199 | } | |
200 | mc_groups = new_groups; | |
201 | mc_groups[mc_groups_longs] = 0; | |
202 | } | |
203 | mc_groups_longs++; | |
204 | } | |
205 | ||
134e6375 JB |
206 | if (family->netnsok) { |
207 | struct net *net; | |
208 | ||
d136f1bd | 209 | netlink_table_grab(); |
134e6375 JB |
210 | rcu_read_lock(); |
211 | for_each_net_rcu(net) { | |
d136f1bd | 212 | err = __netlink_change_ngroups(net->genl_sock, |
134e6375 JB |
213 | mc_groups_longs * BITS_PER_LONG); |
214 | if (err) { | |
215 | /* | |
216 | * No need to roll back, can only fail if | |
217 | * memory allocation fails and then the | |
218 | * number of _possible_ groups has been | |
219 | * increased on some sockets which is ok. | |
220 | */ | |
221 | rcu_read_unlock(); | |
d136f1bd | 222 | netlink_table_ungrab(); |
134e6375 JB |
223 | goto out; |
224 | } | |
225 | } | |
226 | rcu_read_unlock(); | |
d136f1bd | 227 | netlink_table_ungrab(); |
134e6375 JB |
228 | } else { |
229 | err = netlink_change_ngroups(init_net.genl_sock, | |
230 | mc_groups_longs * BITS_PER_LONG); | |
231 | if (err) | |
232 | goto out; | |
233 | } | |
2dbba6f7 JB |
234 | |
235 | grp->id = id; | |
236 | set_bit(id, mc_groups); | |
237 | list_add_tail(&grp->list, &family->mcast_groups); | |
238 | grp->family = family; | |
239 | ||
240 | genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, grp); | |
241 | out: | |
def31174 | 242 | genl_unlock_all(); |
79d310d0 | 243 | return err; |
2dbba6f7 JB |
244 | } |
245 | EXPORT_SYMBOL(genl_register_mc_group); | |
246 | ||
79dc4386 TG |
247 | static void __genl_unregister_mc_group(struct genl_family *family, |
248 | struct genl_multicast_group *grp) | |
249 | { | |
134e6375 | 250 | struct net *net; |
79dc4386 | 251 | BUG_ON(grp->family != family); |
134e6375 | 252 | |
b8273570 | 253 | netlink_table_grab(); |
134e6375 JB |
254 | rcu_read_lock(); |
255 | for_each_net_rcu(net) | |
b8273570 | 256 | __netlink_clear_multicast_users(net->genl_sock, grp->id); |
134e6375 | 257 | rcu_read_unlock(); |
b8273570 | 258 | netlink_table_ungrab(); |
134e6375 | 259 | |
e5dcecba JB |
260 | if (grp->id != 1) |
261 | clear_bit(grp->id, mc_groups); | |
79dc4386 TG |
262 | list_del(&grp->list); |
263 | genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, grp); | |
264 | grp->id = 0; | |
265 | grp->family = NULL; | |
266 | } | |
267 | ||
2dbba6f7 JB |
268 | static void genl_unregister_mc_groups(struct genl_family *family) |
269 | { | |
270 | struct genl_multicast_group *grp, *tmp; | |
271 | ||
272 | list_for_each_entry_safe(grp, tmp, &family->mcast_groups, list) | |
79dc4386 | 273 | __genl_unregister_mc_group(family, grp); |
2dbba6f7 JB |
274 | } |
275 | ||
568508aa | 276 | static int genl_validate_ops(struct genl_family *family) |
482a8524 | 277 | { |
568508aa JB |
278 | const struct genl_ops *ops = family->ops; |
279 | unsigned int n_ops = family->n_ops; | |
d91824c0 JB |
280 | int i, j; |
281 | ||
568508aa JB |
282 | if (WARN_ON(n_ops && !ops)) |
283 | return -EINVAL; | |
284 | ||
285 | if (!n_ops) | |
286 | return 0; | |
287 | ||
d91824c0 JB |
288 | for (i = 0; i < n_ops; i++) { |
289 | if (ops[i].dumpit == NULL && ops[i].doit == NULL) | |
290 | return -EINVAL; | |
291 | for (j = i + 1; j < n_ops; j++) | |
292 | if (ops[i].cmd == ops[j].cmd) | |
293 | return -EINVAL; | |
482a8524 TG |
294 | } |
295 | ||
d91824c0 JB |
296 | /* family is not registered yet, so no locking needed */ |
297 | family->ops = ops; | |
298 | family->n_ops = n_ops; | |
482a8524 | 299 | |
d91824c0 | 300 | return 0; |
482a8524 | 301 | } |
482a8524 TG |
302 | |
303 | /** | |
33c6b1f6 | 304 | * __genl_register_family - register a generic netlink family |
482a8524 TG |
305 | * @family: generic netlink family |
306 | * | |
307 | * Registers the specified family after validating it first. Only one | |
308 | * family may be registered with the same family name or identifier. | |
309 | * The family id may equal GENL_ID_GENERATE causing an unique id to | |
310 | * be automatically generated and assigned. | |
311 | * | |
568508aa JB |
312 | * The family's ops array must already be assigned, you can use the |
313 | * genl_register_family_with_ops() helper function. | |
314 | * | |
482a8524 TG |
315 | * Return 0 on success or a negative error code. |
316 | */ | |
33c6b1f6 | 317 | int __genl_register_family(struct genl_family *family) |
482a8524 TG |
318 | { |
319 | int err = -EINVAL; | |
320 | ||
321 | if (family->id && family->id < GENL_MIN_ID) | |
322 | goto errout; | |
323 | ||
324 | if (family->id > GENL_MAX_ID) | |
325 | goto errout; | |
326 | ||
568508aa JB |
327 | err = genl_validate_ops(family); |
328 | if (err) | |
329 | return err; | |
330 | ||
2dbba6f7 | 331 | INIT_LIST_HEAD(&family->mcast_groups); |
482a8524 | 332 | |
def31174 | 333 | genl_lock_all(); |
482a8524 TG |
334 | |
335 | if (genl_family_find_byname(family->name)) { | |
336 | err = -EEXIST; | |
337 | goto errout_locked; | |
338 | } | |
339 | ||
482a8524 TG |
340 | if (family->id == GENL_ID_GENERATE) { |
341 | u16 newid = genl_generate_id(); | |
342 | ||
343 | if (!newid) { | |
344 | err = -ENOMEM; | |
345 | goto errout_locked; | |
346 | } | |
347 | ||
348 | family->id = newid; | |
93860b08 KK |
349 | } else if (genl_family_find_byid(family->id)) { |
350 | err = -EEXIST; | |
351 | goto errout_locked; | |
482a8524 TG |
352 | } |
353 | ||
def31174 | 354 | if (family->maxattr && !family->parallel_ops) { |
482a8524 TG |
355 | family->attrbuf = kmalloc((family->maxattr+1) * |
356 | sizeof(struct nlattr *), GFP_KERNEL); | |
357 | if (family->attrbuf == NULL) { | |
358 | err = -ENOMEM; | |
e200bd80 | 359 | goto errout_locked; |
482a8524 TG |
360 | } |
361 | } else | |
362 | family->attrbuf = NULL; | |
363 | ||
364 | list_add_tail(&family->family_list, genl_family_chain(family->id)); | |
def31174 | 365 | genl_unlock_all(); |
482a8524 TG |
366 | |
367 | genl_ctrl_event(CTRL_CMD_NEWFAMILY, family); | |
368 | ||
369 | return 0; | |
370 | ||
371 | errout_locked: | |
def31174 | 372 | genl_unlock_all(); |
482a8524 TG |
373 | errout: |
374 | return err; | |
375 | } | |
33c6b1f6 | 376 | EXPORT_SYMBOL(__genl_register_family); |
482a8524 TG |
377 | |
378 | /** | |
379 | * genl_unregister_family - unregister generic netlink family | |
380 | * @family: generic netlink family | |
381 | * | |
382 | * Unregisters the specified family. | |
383 | * | |
384 | * Returns 0 on success or a negative error code. | |
385 | */ | |
386 | int genl_unregister_family(struct genl_family *family) | |
387 | { | |
388 | struct genl_family *rc; | |
389 | ||
def31174 | 390 | genl_lock_all(); |
482a8524 | 391 | |
910d6c32 PE |
392 | genl_unregister_mc_groups(family); |
393 | ||
482a8524 TG |
394 | list_for_each_entry(rc, genl_family_chain(family->id), family_list) { |
395 | if (family->id != rc->id || strcmp(rc->name, family->name)) | |
396 | continue; | |
397 | ||
398 | list_del(&rc->family_list); | |
d91824c0 | 399 | family->n_ops = 0; |
def31174 | 400 | genl_unlock_all(); |
482a8524 | 401 | |
482a8524 TG |
402 | kfree(family->attrbuf); |
403 | genl_ctrl_event(CTRL_CMD_DELFAMILY, family); | |
404 | return 0; | |
405 | } | |
406 | ||
def31174 | 407 | genl_unlock_all(); |
482a8524 TG |
408 | |
409 | return -ENOENT; | |
410 | } | |
416c2f9c | 411 | EXPORT_SYMBOL(genl_unregister_family); |
482a8524 | 412 | |
a46621a3 DV |
413 | /** |
414 | * genlmsg_put - Add generic netlink header to netlink message | |
415 | * @skb: socket buffer holding the message | |
15e47304 | 416 | * @portid: netlink portid the message is addressed to |
a46621a3 DV |
417 | * @seq: sequence number (usually the one of the sender) |
418 | * @family: generic netlink family | |
2c53040f | 419 | * @flags: netlink message flags |
a46621a3 DV |
420 | * @cmd: generic netlink command |
421 | * | |
422 | * Returns pointer to user specific header | |
423 | */ | |
15e47304 | 424 | void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, |
a46621a3 DV |
425 | struct genl_family *family, int flags, u8 cmd) |
426 | { | |
427 | struct nlmsghdr *nlh; | |
428 | struct genlmsghdr *hdr; | |
429 | ||
15e47304 | 430 | nlh = nlmsg_put(skb, portid, seq, family->id, GENL_HDRLEN + |
a46621a3 DV |
431 | family->hdrsize, flags); |
432 | if (nlh == NULL) | |
433 | return NULL; | |
434 | ||
435 | hdr = nlmsg_data(nlh); | |
436 | hdr->cmd = cmd; | |
437 | hdr->version = family->version; | |
438 | hdr->reserved = 0; | |
439 | ||
440 | return (char *) hdr + GENL_HDRLEN; | |
441 | } | |
442 | EXPORT_SYMBOL(genlmsg_put); | |
443 | ||
9b96309c PS |
444 | static int genl_lock_dumpit(struct sk_buff *skb, struct netlink_callback *cb) |
445 | { | |
f84f771d JB |
446 | /* our ops are always const - netlink API doesn't propagate that */ |
447 | const struct genl_ops *ops = cb->data; | |
9b96309c PS |
448 | int rc; |
449 | ||
450 | genl_lock(); | |
451 | rc = ops->dumpit(skb, cb); | |
452 | genl_unlock(); | |
453 | return rc; | |
454 | } | |
455 | ||
456 | static int genl_lock_done(struct netlink_callback *cb) | |
457 | { | |
f84f771d JB |
458 | /* our ops are always const - netlink API doesn't propagate that */ |
459 | const struct genl_ops *ops = cb->data; | |
9b96309c PS |
460 | int rc = 0; |
461 | ||
462 | if (ops->done) { | |
463 | genl_lock(); | |
464 | rc = ops->done(cb); | |
465 | genl_unlock(); | |
466 | } | |
467 | return rc; | |
468 | } | |
469 | ||
def31174 PS |
470 | static int genl_family_rcv_msg(struct genl_family *family, |
471 | struct sk_buff *skb, | |
472 | struct nlmsghdr *nlh) | |
482a8524 | 473 | { |
f84f771d | 474 | const struct genl_ops *ops; |
134e6375 | 475 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
476 | struct genl_info info; |
477 | struct genlmsghdr *hdr = nlmsg_data(nlh); | |
def31174 | 478 | struct nlattr **attrbuf; |
1d00a4eb | 479 | int hdrlen, err; |
482a8524 | 480 | |
134e6375 JB |
481 | /* this family doesn't exist in this netns */ |
482 | if (!family->netnsok && !net_eq(net, &init_net)) | |
483 | return -ENOENT; | |
484 | ||
482a8524 TG |
485 | hdrlen = GENL_HDRLEN + family->hdrsize; |
486 | if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) | |
1d00a4eb | 487 | return -EINVAL; |
482a8524 TG |
488 | |
489 | ops = genl_get_cmd(hdr->cmd, family); | |
1d00a4eb TG |
490 | if (ops == NULL) |
491 | return -EOPNOTSUPP; | |
482a8524 | 492 | |
1d00a4eb | 493 | if ((ops->flags & GENL_ADMIN_PERM) && |
fd778461 | 494 | !capable(CAP_NET_ADMIN)) |
1d00a4eb | 495 | return -EPERM; |
482a8524 | 496 | |
e1ee3673 | 497 | if ((nlh->nlmsg_flags & NLM_F_DUMP) == NLM_F_DUMP) { |
9b96309c | 498 | int rc; |
def31174 | 499 | |
1d00a4eb TG |
500 | if (ops->dumpit == NULL) |
501 | return -EOPNOTSUPP; | |
482a8524 | 502 | |
9b96309c PS |
503 | if (!family->parallel_ops) { |
504 | struct netlink_dump_control c = { | |
33c6b1f6 | 505 | .module = family->module, |
f84f771d JB |
506 | /* we have const, but the netlink API doesn't */ |
507 | .data = (void *)ops, | |
9b96309c PS |
508 | .dump = genl_lock_dumpit, |
509 | .done = genl_lock_done, | |
510 | }; | |
511 | ||
512 | genl_unlock(); | |
33c6b1f6 | 513 | rc = __netlink_dump_start(net->genl_sock, skb, nlh, &c); |
9b96309c PS |
514 | genl_lock(); |
515 | ||
516 | } else { | |
517 | struct netlink_dump_control c = { | |
33c6b1f6 | 518 | .module = family->module, |
9b96309c PS |
519 | .dump = ops->dumpit, |
520 | .done = ops->done, | |
521 | }; | |
522 | ||
33c6b1f6 | 523 | rc = __netlink_dump_start(net->genl_sock, skb, nlh, &c); |
9b96309c PS |
524 | } |
525 | ||
526 | return rc; | |
482a8524 TG |
527 | } |
528 | ||
1d00a4eb TG |
529 | if (ops->doit == NULL) |
530 | return -EOPNOTSUPP; | |
482a8524 | 531 | |
def31174 PS |
532 | if (family->maxattr && family->parallel_ops) { |
533 | attrbuf = kmalloc((family->maxattr+1) * | |
534 | sizeof(struct nlattr *), GFP_KERNEL); | |
535 | if (attrbuf == NULL) | |
536 | return -ENOMEM; | |
537 | } else | |
538 | attrbuf = family->attrbuf; | |
539 | ||
540 | if (attrbuf) { | |
541 | err = nlmsg_parse(nlh, hdrlen, attrbuf, family->maxattr, | |
482a8524 TG |
542 | ops->policy); |
543 | if (err < 0) | |
50754d21 | 544 | goto out; |
482a8524 TG |
545 | } |
546 | ||
547 | info.snd_seq = nlh->nlmsg_seq; | |
15e47304 | 548 | info.snd_portid = NETLINK_CB(skb).portid; |
482a8524 TG |
549 | info.nlhdr = nlh; |
550 | info.genlhdr = nlmsg_data(nlh); | |
551 | info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN; | |
def31174 | 552 | info.attrs = attrbuf; |
134e6375 | 553 | genl_info_net_set(&info, net); |
ff4c92d8 | 554 | memset(&info.user_ptr, 0, sizeof(info.user_ptr)); |
482a8524 | 555 | |
ff4c92d8 JB |
556 | if (family->pre_doit) { |
557 | err = family->pre_doit(ops, skb, &info); | |
558 | if (err) | |
50754d21 | 559 | goto out; |
ff4c92d8 JB |
560 | } |
561 | ||
562 | err = ops->doit(skb, &info); | |
563 | ||
564 | if (family->post_doit) | |
565 | family->post_doit(ops, skb, &info); | |
566 | ||
50754d21 | 567 | out: |
def31174 PS |
568 | if (family->parallel_ops) |
569 | kfree(attrbuf); | |
570 | ||
571 | return err; | |
572 | } | |
573 | ||
574 | static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) | |
575 | { | |
576 | struct genl_family *family; | |
577 | int err; | |
578 | ||
579 | family = genl_family_find_byid(nlh->nlmsg_type); | |
580 | if (family == NULL) | |
581 | return -ENOENT; | |
582 | ||
583 | if (!family->parallel_ops) | |
584 | genl_lock(); | |
585 | ||
586 | err = genl_family_rcv_msg(family, skb, nlh); | |
587 | ||
588 | if (!family->parallel_ops) | |
589 | genl_unlock(); | |
590 | ||
ff4c92d8 | 591 | return err; |
482a8524 TG |
592 | } |
593 | ||
cd40b7d3 | 594 | static void genl_rcv(struct sk_buff *skb) |
482a8524 | 595 | { |
def31174 | 596 | down_read(&cb_lock); |
cd40b7d3 | 597 | netlink_rcv_skb(skb, &genl_rcv_msg); |
def31174 | 598 | up_read(&cb_lock); |
482a8524 TG |
599 | } |
600 | ||
601 | /************************************************************************** | |
602 | * Controller | |
603 | **************************************************************************/ | |
604 | ||
17c157c8 TG |
605 | static struct genl_family genl_ctrl = { |
606 | .id = GENL_ID_CTRL, | |
607 | .name = "nlctrl", | |
334c29a6 | 608 | .version = 0x2, |
17c157c8 | 609 | .maxattr = CTRL_ATTR_MAX, |
134e6375 | 610 | .netnsok = true, |
17c157c8 TG |
611 | }; |
612 | ||
15e47304 | 613 | static int ctrl_fill_info(struct genl_family *family, u32 portid, u32 seq, |
482a8524 TG |
614 | u32 flags, struct sk_buff *skb, u8 cmd) |
615 | { | |
616 | void *hdr; | |
617 | ||
15e47304 | 618 | hdr = genlmsg_put(skb, portid, seq, &genl_ctrl, flags, cmd); |
482a8524 TG |
619 | if (hdr == NULL) |
620 | return -1; | |
621 | ||
444653f6 DM |
622 | if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, family->name) || |
623 | nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, family->id) || | |
624 | nla_put_u32(skb, CTRL_ATTR_VERSION, family->version) || | |
625 | nla_put_u32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize) || | |
626 | nla_put_u32(skb, CTRL_ATTR_MAXATTR, family->maxattr)) | |
627 | goto nla_put_failure; | |
eb328111 | 628 | |
d91824c0 | 629 | if (family->n_ops) { |
e94ef682 | 630 | struct nlattr *nla_ops; |
d91824c0 | 631 | int i; |
eb328111 | 632 | |
e94ef682 TG |
633 | nla_ops = nla_nest_start(skb, CTRL_ATTR_OPS); |
634 | if (nla_ops == NULL) | |
eb328111 TG |
635 | goto nla_put_failure; |
636 | ||
d91824c0 | 637 | for (i = 0; i < family->n_ops; i++) { |
e94ef682 | 638 | struct nlattr *nest; |
f84f771d | 639 | const struct genl_ops *ops = &family->ops[i]; |
029b234f | 640 | u32 op_flags = ops->flags; |
f84f771d JB |
641 | |
642 | if (ops->dumpit) | |
029b234f | 643 | op_flags |= GENL_CMD_CAP_DUMP; |
f84f771d | 644 | if (ops->doit) |
029b234f | 645 | op_flags |= GENL_CMD_CAP_DO; |
f84f771d | 646 | if (ops->policy) |
029b234f | 647 | op_flags |= GENL_CMD_CAP_HASPOL; |
eb328111 | 648 | |
d91824c0 | 649 | nest = nla_nest_start(skb, i + 1); |
e94ef682 TG |
650 | if (nest == NULL) |
651 | goto nla_put_failure; | |
eb328111 | 652 | |
444653f6 | 653 | if (nla_put_u32(skb, CTRL_ATTR_OP_ID, ops->cmd) || |
029b234f | 654 | nla_put_u32(skb, CTRL_ATTR_OP_FLAGS, op_flags)) |
444653f6 | 655 | goto nla_put_failure; |
eb328111 | 656 | |
e94ef682 TG |
657 | nla_nest_end(skb, nest); |
658 | } | |
659 | ||
660 | nla_nest_end(skb, nla_ops); | |
661 | } | |
482a8524 | 662 | |
2dbba6f7 JB |
663 | if (!list_empty(&family->mcast_groups)) { |
664 | struct genl_multicast_group *grp; | |
665 | struct nlattr *nla_grps; | |
666 | int idx = 1; | |
667 | ||
668 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
669 | if (nla_grps == NULL) | |
670 | goto nla_put_failure; | |
671 | ||
672 | list_for_each_entry(grp, &family->mcast_groups, list) { | |
673 | struct nlattr *nest; | |
674 | ||
675 | nest = nla_nest_start(skb, idx++); | |
676 | if (nest == NULL) | |
677 | goto nla_put_failure; | |
678 | ||
444653f6 DM |
679 | if (nla_put_u32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id) || |
680 | nla_put_string(skb, CTRL_ATTR_MCAST_GRP_NAME, | |
681 | grp->name)) | |
682 | goto nla_put_failure; | |
2dbba6f7 JB |
683 | |
684 | nla_nest_end(skb, nest); | |
685 | } | |
686 | nla_nest_end(skb, nla_grps); | |
687 | } | |
688 | ||
689 | return genlmsg_end(skb, hdr); | |
690 | ||
691 | nla_put_failure: | |
bc3ed28c TG |
692 | genlmsg_cancel(skb, hdr); |
693 | return -EMSGSIZE; | |
2dbba6f7 JB |
694 | } |
695 | ||
15e47304 | 696 | static int ctrl_fill_mcgrp_info(struct genl_multicast_group *grp, u32 portid, |
2dbba6f7 JB |
697 | u32 seq, u32 flags, struct sk_buff *skb, |
698 | u8 cmd) | |
699 | { | |
700 | void *hdr; | |
701 | struct nlattr *nla_grps; | |
702 | struct nlattr *nest; | |
703 | ||
15e47304 | 704 | hdr = genlmsg_put(skb, portid, seq, &genl_ctrl, flags, cmd); |
2dbba6f7 JB |
705 | if (hdr == NULL) |
706 | return -1; | |
707 | ||
444653f6 DM |
708 | if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, grp->family->name) || |
709 | nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, grp->family->id)) | |
710 | goto nla_put_failure; | |
2dbba6f7 JB |
711 | |
712 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
713 | if (nla_grps == NULL) | |
714 | goto nla_put_failure; | |
715 | ||
716 | nest = nla_nest_start(skb, 1); | |
717 | if (nest == NULL) | |
718 | goto nla_put_failure; | |
719 | ||
444653f6 DM |
720 | if (nla_put_u32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id) || |
721 | nla_put_string(skb, CTRL_ATTR_MCAST_GRP_NAME, | |
722 | grp->name)) | |
723 | goto nla_put_failure; | |
2dbba6f7 JB |
724 | |
725 | nla_nest_end(skb, nest); | |
726 | nla_nest_end(skb, nla_grps); | |
727 | ||
482a8524 TG |
728 | return genlmsg_end(skb, hdr); |
729 | ||
730 | nla_put_failure: | |
bc3ed28c TG |
731 | genlmsg_cancel(skb, hdr); |
732 | return -EMSGSIZE; | |
482a8524 TG |
733 | } |
734 | ||
735 | static int ctrl_dumpfamily(struct sk_buff *skb, struct netlink_callback *cb) | |
736 | { | |
737 | ||
738 | int i, n = 0; | |
739 | struct genl_family *rt; | |
134e6375 | 740 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
741 | int chains_to_skip = cb->args[0]; |
742 | int fams_to_skip = cb->args[1]; | |
743 | ||
e1d5a010 | 744 | for (i = chains_to_skip; i < GENL_FAM_TAB_SIZE; i++) { |
482a8524 TG |
745 | n = 0; |
746 | list_for_each_entry(rt, genl_family_chain(i), family_list) { | |
134e6375 JB |
747 | if (!rt->netnsok && !net_eq(net, &init_net)) |
748 | continue; | |
482a8524 TG |
749 | if (++n < fams_to_skip) |
750 | continue; | |
15e47304 | 751 | if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).portid, |
482a8524 TG |
752 | cb->nlh->nlmsg_seq, NLM_F_MULTI, |
753 | skb, CTRL_CMD_NEWFAMILY) < 0) | |
754 | goto errout; | |
755 | } | |
756 | ||
757 | fams_to_skip = 0; | |
758 | } | |
759 | ||
760 | errout: | |
761 | cb->args[0] = i; | |
762 | cb->args[1] = n; | |
763 | ||
764 | return skb->len; | |
765 | } | |
766 | ||
2dbba6f7 | 767 | static struct sk_buff *ctrl_build_family_msg(struct genl_family *family, |
15e47304 | 768 | u32 portid, int seq, u8 cmd) |
482a8524 TG |
769 | { |
770 | struct sk_buff *skb; | |
771 | int err; | |
772 | ||
339bf98f | 773 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); |
482a8524 TG |
774 | if (skb == NULL) |
775 | return ERR_PTR(-ENOBUFS); | |
776 | ||
15e47304 | 777 | err = ctrl_fill_info(family, portid, seq, 0, skb, cmd); |
482a8524 TG |
778 | if (err < 0) { |
779 | nlmsg_free(skb); | |
780 | return ERR_PTR(err); | |
781 | } | |
782 | ||
783 | return skb; | |
784 | } | |
785 | ||
2dbba6f7 | 786 | static struct sk_buff *ctrl_build_mcgrp_msg(struct genl_multicast_group *grp, |
15e47304 | 787 | u32 portid, int seq, u8 cmd) |
2dbba6f7 JB |
788 | { |
789 | struct sk_buff *skb; | |
790 | int err; | |
791 | ||
792 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); | |
793 | if (skb == NULL) | |
794 | return ERR_PTR(-ENOBUFS); | |
795 | ||
15e47304 | 796 | err = ctrl_fill_mcgrp_info(grp, portid, seq, 0, skb, cmd); |
2dbba6f7 JB |
797 | if (err < 0) { |
798 | nlmsg_free(skb); | |
799 | return ERR_PTR(err); | |
800 | } | |
801 | ||
802 | return skb; | |
803 | } | |
804 | ||
ef7c79ed | 805 | static const struct nla_policy ctrl_policy[CTRL_ATTR_MAX+1] = { |
482a8524 | 806 | [CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 }, |
5176f91e TG |
807 | [CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING, |
808 | .len = GENL_NAMSIZ - 1 }, | |
482a8524 TG |
809 | }; |
810 | ||
811 | static int ctrl_getfamily(struct sk_buff *skb, struct genl_info *info) | |
812 | { | |
813 | struct sk_buff *msg; | |
814 | struct genl_family *res = NULL; | |
815 | int err = -EINVAL; | |
816 | ||
817 | if (info->attrs[CTRL_ATTR_FAMILY_ID]) { | |
818 | u16 id = nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]); | |
819 | res = genl_family_find_byid(id); | |
134e6375 | 820 | err = -ENOENT; |
482a8524 TG |
821 | } |
822 | ||
823 | if (info->attrs[CTRL_ATTR_FAMILY_NAME]) { | |
5176f91e | 824 | char *name; |
482a8524 | 825 | |
5176f91e | 826 | name = nla_data(info->attrs[CTRL_ATTR_FAMILY_NAME]); |
482a8524 | 827 | res = genl_family_find_byname(name); |
fa843095 SH |
828 | #ifdef CONFIG_MODULES |
829 | if (res == NULL) { | |
830 | genl_unlock(); | |
c74f2b26 | 831 | up_read(&cb_lock); |
e9412c37 | 832 | request_module("net-pf-%d-proto-%d-family-%s", |
fa843095 | 833 | PF_NETLINK, NETLINK_GENERIC, name); |
c74f2b26 | 834 | down_read(&cb_lock); |
fa843095 SH |
835 | genl_lock(); |
836 | res = genl_family_find_byname(name); | |
837 | } | |
838 | #endif | |
134e6375 | 839 | err = -ENOENT; |
482a8524 TG |
840 | } |
841 | ||
134e6375 JB |
842 | if (res == NULL) |
843 | return err; | |
844 | ||
845 | if (!res->netnsok && !net_eq(genl_info_net(info), &init_net)) { | |
846 | /* family doesn't exist here */ | |
847 | return -ENOENT; | |
482a8524 TG |
848 | } |
849 | ||
15e47304 | 850 | msg = ctrl_build_family_msg(res, info->snd_portid, info->snd_seq, |
2dbba6f7 | 851 | CTRL_CMD_NEWFAMILY); |
134e6375 JB |
852 | if (IS_ERR(msg)) |
853 | return PTR_ERR(msg); | |
482a8524 | 854 | |
134e6375 | 855 | return genlmsg_reply(msg, info); |
482a8524 TG |
856 | } |
857 | ||
858 | static int genl_ctrl_event(int event, void *data) | |
859 | { | |
860 | struct sk_buff *msg; | |
134e6375 JB |
861 | struct genl_family *family; |
862 | struct genl_multicast_group *grp; | |
482a8524 | 863 | |
134e6375 JB |
864 | /* genl is still initialising */ |
865 | if (!init_net.genl_sock) | |
482a8524 TG |
866 | return 0; |
867 | ||
868 | switch (event) { | |
869 | case CTRL_CMD_NEWFAMILY: | |
870 | case CTRL_CMD_DELFAMILY: | |
134e6375 JB |
871 | family = data; |
872 | msg = ctrl_build_family_msg(family, 0, 0, event); | |
2dbba6f7 JB |
873 | break; |
874 | case CTRL_CMD_NEWMCAST_GRP: | |
875 | case CTRL_CMD_DELMCAST_GRP: | |
134e6375 JB |
876 | grp = data; |
877 | family = grp->family; | |
2dbba6f7 | 878 | msg = ctrl_build_mcgrp_msg(data, 0, 0, event); |
482a8524 | 879 | break; |
134e6375 JB |
880 | default: |
881 | return -EINVAL; | |
882 | } | |
883 | ||
884 | if (IS_ERR(msg)) | |
885 | return PTR_ERR(msg); | |
886 | ||
887 | if (!family->netnsok) { | |
888 | genlmsg_multicast_netns(&init_net, msg, 0, | |
889 | GENL_ID_CTRL, GFP_KERNEL); | |
890 | } else { | |
891 | rcu_read_lock(); | |
892 | genlmsg_multicast_allns(msg, 0, GENL_ID_CTRL, GFP_ATOMIC); | |
893 | rcu_read_unlock(); | |
482a8524 TG |
894 | } |
895 | ||
896 | return 0; | |
897 | } | |
898 | ||
c53ed742 JB |
899 | static struct genl_ops genl_ctrl_ops[] = { |
900 | { | |
901 | .cmd = CTRL_CMD_GETFAMILY, | |
902 | .doit = ctrl_getfamily, | |
903 | .dumpit = ctrl_dumpfamily, | |
904 | .policy = ctrl_policy, | |
905 | }, | |
482a8524 TG |
906 | }; |
907 | ||
2dbba6f7 JB |
908 | static struct genl_multicast_group notify_grp = { |
909 | .name = "notify", | |
910 | }; | |
911 | ||
134e6375 JB |
912 | static int __net_init genl_pernet_init(struct net *net) |
913 | { | |
a31f2d17 PNA |
914 | struct netlink_kernel_cfg cfg = { |
915 | .input = genl_rcv, | |
9785e10a | 916 | .flags = NL_CFG_F_NONROOT_RECV, |
a31f2d17 PNA |
917 | }; |
918 | ||
134e6375 | 919 | /* we'll bump the group number right afterwards */ |
9f00d977 | 920 | net->genl_sock = netlink_kernel_create(net, NETLINK_GENERIC, &cfg); |
134e6375 JB |
921 | |
922 | if (!net->genl_sock && net_eq(net, &init_net)) | |
923 | panic("GENL: Cannot initialize generic netlink\n"); | |
924 | ||
925 | if (!net->genl_sock) | |
926 | return -ENOMEM; | |
927 | ||
928 | return 0; | |
929 | } | |
930 | ||
931 | static void __net_exit genl_pernet_exit(struct net *net) | |
932 | { | |
933 | netlink_kernel_release(net->genl_sock); | |
934 | net->genl_sock = NULL; | |
935 | } | |
936 | ||
937 | static struct pernet_operations genl_pernet_ops = { | |
938 | .init = genl_pernet_init, | |
939 | .exit = genl_pernet_exit, | |
940 | }; | |
941 | ||
482a8524 TG |
942 | static int __init genl_init(void) |
943 | { | |
944 | int i, err; | |
945 | ||
946 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) | |
947 | INIT_LIST_HEAD(&family_ht[i]); | |
948 | ||
c53ed742 | 949 | err = genl_register_family_with_ops(&genl_ctrl, genl_ctrl_ops); |
482a8524 | 950 | if (err < 0) |
134e6375 | 951 | goto problem; |
482a8524 | 952 | |
134e6375 JB |
953 | err = register_pernet_subsys(&genl_pernet_ops); |
954 | if (err) | |
955 | goto problem; | |
482a8524 | 956 | |
2dbba6f7 JB |
957 | err = genl_register_mc_group(&genl_ctrl, ¬ify_grp); |
958 | if (err < 0) | |
134e6375 | 959 | goto problem; |
2dbba6f7 | 960 | |
482a8524 TG |
961 | return 0; |
962 | ||
134e6375 | 963 | problem: |
482a8524 | 964 | panic("GENL: Cannot register controller: %d\n", err); |
482a8524 TG |
965 | } |
966 | ||
967 | subsys_initcall(genl_init); | |
968 | ||
15e47304 | 969 | static int genlmsg_mcast(struct sk_buff *skb, u32 portid, unsigned long group, |
134e6375 JB |
970 | gfp_t flags) |
971 | { | |
972 | struct sk_buff *tmp; | |
973 | struct net *net, *prev = NULL; | |
974 | int err; | |
975 | ||
976 | for_each_net_rcu(net) { | |
977 | if (prev) { | |
978 | tmp = skb_clone(skb, flags); | |
979 | if (!tmp) { | |
980 | err = -ENOMEM; | |
981 | goto error; | |
982 | } | |
983 | err = nlmsg_multicast(prev->genl_sock, tmp, | |
15e47304 | 984 | portid, group, flags); |
134e6375 JB |
985 | if (err) |
986 | goto error; | |
987 | } | |
988 | ||
989 | prev = net; | |
990 | } | |
991 | ||
15e47304 | 992 | return nlmsg_multicast(prev->genl_sock, skb, portid, group, flags); |
134e6375 JB |
993 | error: |
994 | kfree_skb(skb); | |
995 | return err; | |
996 | } | |
997 | ||
15e47304 | 998 | int genlmsg_multicast_allns(struct sk_buff *skb, u32 portid, unsigned int group, |
134e6375 JB |
999 | gfp_t flags) |
1000 | { | |
15e47304 | 1001 | return genlmsg_mcast(skb, portid, group, flags); |
134e6375 JB |
1002 | } |
1003 | EXPORT_SYMBOL(genlmsg_multicast_allns); | |
263ba61d | 1004 | |
15e47304 | 1005 | void genl_notify(struct sk_buff *skb, struct net *net, u32 portid, u32 group, |
263ba61d PS |
1006 | struct nlmsghdr *nlh, gfp_t flags) |
1007 | { | |
1008 | struct sock *sk = net->genl_sock; | |
1009 | int report = 0; | |
1010 | ||
1011 | if (nlh) | |
1012 | report = nlmsg_report(nlh); | |
1013 | ||
15e47304 | 1014 | nlmsg_notify(sk, skb, portid, group, report, flags); |
263ba61d PS |
1015 | } |
1016 | EXPORT_SYMBOL(genl_notify); |