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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 | |
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. | |
68 | */ | |
69 | static unsigned long mc_group_start = 0x1; | |
70 | static unsigned long *mc_groups = &mc_group_start; | |
71 | static unsigned long mc_groups_longs = 1; | |
482a8524 TG |
72 | |
73 | static int genl_ctrl_event(int event, void *data); | |
74 | ||
75 | static inline unsigned int genl_family_hash(unsigned int id) | |
76 | { | |
77 | return id & GENL_FAM_TAB_MASK; | |
78 | } | |
79 | ||
80 | static inline struct list_head *genl_family_chain(unsigned int id) | |
81 | { | |
82 | return &family_ht[genl_family_hash(id)]; | |
83 | } | |
84 | ||
85 | static struct genl_family *genl_family_find_byid(unsigned int id) | |
86 | { | |
87 | struct genl_family *f; | |
88 | ||
89 | list_for_each_entry(f, genl_family_chain(id), family_list) | |
90 | if (f->id == id) | |
91 | return f; | |
92 | ||
93 | return NULL; | |
94 | } | |
95 | ||
96 | static struct genl_family *genl_family_find_byname(char *name) | |
97 | { | |
98 | struct genl_family *f; | |
99 | int i; | |
100 | ||
101 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) | |
102 | list_for_each_entry(f, genl_family_chain(i), family_list) | |
103 | if (strcmp(f->name, name) == 0) | |
104 | return f; | |
105 | ||
106 | return NULL; | |
107 | } | |
108 | ||
f84f771d | 109 | static const struct genl_ops *genl_get_cmd(u8 cmd, struct genl_family *family) |
482a8524 | 110 | { |
d91824c0 | 111 | int i; |
482a8524 | 112 | |
d91824c0 JB |
113 | for (i = 0; i < family->n_ops; i++) |
114 | if (family->ops[i].cmd == cmd) | |
115 | return &family->ops[i]; | |
482a8524 TG |
116 | |
117 | return NULL; | |
118 | } | |
119 | ||
120 | /* Of course we are going to have problems once we hit | |
121 | * 2^16 alive types, but that can only happen by year 2K | |
122 | */ | |
b57ef81f | 123 | static u16 genl_generate_id(void) |
482a8524 | 124 | { |
988ade6b KK |
125 | static u16 id_gen_idx = GENL_MIN_ID; |
126 | int i; | |
482a8524 | 127 | |
988ade6b KK |
128 | for (i = 0; i <= GENL_MAX_ID - GENL_MIN_ID; i++) { |
129 | if (!genl_family_find_byid(id_gen_idx)) | |
130 | return id_gen_idx; | |
131 | if (++id_gen_idx > GENL_MAX_ID) | |
482a8524 | 132 | id_gen_idx = GENL_MIN_ID; |
988ade6b | 133 | } |
482a8524 | 134 | |
988ade6b | 135 | return 0; |
482a8524 TG |
136 | } |
137 | ||
2dbba6f7 JB |
138 | static struct genl_multicast_group notify_grp; |
139 | ||
140 | /** | |
141 | * genl_register_mc_group - register a multicast group | |
142 | * | |
143 | * Registers the specified multicast group and notifies userspace | |
144 | * about the new group. | |
145 | * | |
146 | * Returns 0 on success or a negative error code. | |
147 | * | |
148 | * @family: The generic netlink family the group shall be registered for. | |
149 | * @grp: The group to register, must have a name. | |
150 | */ | |
151 | int genl_register_mc_group(struct genl_family *family, | |
152 | struct genl_multicast_group *grp) | |
153 | { | |
154 | int id; | |
155 | unsigned long *new_groups; | |
b1f57195 | 156 | int err = 0; |
2dbba6f7 JB |
157 | |
158 | BUG_ON(grp->name[0] == '\0'); | |
f1e79e20 | 159 | BUG_ON(memchr(grp->name, '\0', GENL_NAMSIZ) == NULL); |
2dbba6f7 | 160 | |
def31174 | 161 | genl_lock_all(); |
2dbba6f7 JB |
162 | |
163 | /* special-case our own group */ | |
164 | if (grp == ¬ify_grp) | |
165 | id = GENL_ID_CTRL; | |
166 | else | |
167 | id = find_first_zero_bit(mc_groups, | |
168 | mc_groups_longs * BITS_PER_LONG); | |
169 | ||
170 | ||
171 | if (id >= mc_groups_longs * BITS_PER_LONG) { | |
172 | size_t nlen = (mc_groups_longs + 1) * sizeof(unsigned long); | |
173 | ||
174 | if (mc_groups == &mc_group_start) { | |
175 | new_groups = kzalloc(nlen, GFP_KERNEL); | |
176 | if (!new_groups) { | |
177 | err = -ENOMEM; | |
178 | goto out; | |
179 | } | |
180 | mc_groups = new_groups; | |
181 | *mc_groups = mc_group_start; | |
182 | } else { | |
183 | new_groups = krealloc(mc_groups, nlen, GFP_KERNEL); | |
184 | if (!new_groups) { | |
185 | err = -ENOMEM; | |
186 | goto out; | |
187 | } | |
188 | mc_groups = new_groups; | |
189 | mc_groups[mc_groups_longs] = 0; | |
190 | } | |
191 | mc_groups_longs++; | |
192 | } | |
193 | ||
134e6375 JB |
194 | if (family->netnsok) { |
195 | struct net *net; | |
196 | ||
d136f1bd | 197 | netlink_table_grab(); |
134e6375 JB |
198 | rcu_read_lock(); |
199 | for_each_net_rcu(net) { | |
d136f1bd | 200 | err = __netlink_change_ngroups(net->genl_sock, |
134e6375 JB |
201 | mc_groups_longs * BITS_PER_LONG); |
202 | if (err) { | |
203 | /* | |
204 | * No need to roll back, can only fail if | |
205 | * memory allocation fails and then the | |
206 | * number of _possible_ groups has been | |
207 | * increased on some sockets which is ok. | |
208 | */ | |
209 | rcu_read_unlock(); | |
d136f1bd | 210 | netlink_table_ungrab(); |
134e6375 JB |
211 | goto out; |
212 | } | |
213 | } | |
214 | rcu_read_unlock(); | |
d136f1bd | 215 | netlink_table_ungrab(); |
134e6375 JB |
216 | } else { |
217 | err = netlink_change_ngroups(init_net.genl_sock, | |
218 | mc_groups_longs * BITS_PER_LONG); | |
219 | if (err) | |
220 | goto out; | |
221 | } | |
2dbba6f7 JB |
222 | |
223 | grp->id = id; | |
224 | set_bit(id, mc_groups); | |
225 | list_add_tail(&grp->list, &family->mcast_groups); | |
226 | grp->family = family; | |
227 | ||
228 | genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, grp); | |
229 | out: | |
def31174 | 230 | genl_unlock_all(); |
79d310d0 | 231 | return err; |
2dbba6f7 JB |
232 | } |
233 | EXPORT_SYMBOL(genl_register_mc_group); | |
234 | ||
79dc4386 TG |
235 | static void __genl_unregister_mc_group(struct genl_family *family, |
236 | struct genl_multicast_group *grp) | |
237 | { | |
134e6375 | 238 | struct net *net; |
79dc4386 | 239 | BUG_ON(grp->family != family); |
134e6375 | 240 | |
b8273570 | 241 | netlink_table_grab(); |
134e6375 JB |
242 | rcu_read_lock(); |
243 | for_each_net_rcu(net) | |
b8273570 | 244 | __netlink_clear_multicast_users(net->genl_sock, grp->id); |
134e6375 | 245 | rcu_read_unlock(); |
b8273570 | 246 | netlink_table_ungrab(); |
134e6375 | 247 | |
79dc4386 TG |
248 | clear_bit(grp->id, mc_groups); |
249 | list_del(&grp->list); | |
250 | genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, grp); | |
251 | grp->id = 0; | |
252 | grp->family = NULL; | |
253 | } | |
254 | ||
2dbba6f7 JB |
255 | /** |
256 | * genl_unregister_mc_group - unregister a multicast group | |
257 | * | |
258 | * Unregisters the specified multicast group and notifies userspace | |
259 | * about it. All current listeners on the group are removed. | |
260 | * | |
261 | * Note: It is not necessary to unregister all multicast groups before | |
262 | * unregistering the family, unregistering the family will cause | |
263 | * all assigned multicast groups to be unregistered automatically. | |
264 | * | |
265 | * @family: Generic netlink family the group belongs to. | |
266 | * @grp: The group to unregister, must have been registered successfully | |
267 | * previously. | |
268 | */ | |
269 | void genl_unregister_mc_group(struct genl_family *family, | |
270 | struct genl_multicast_group *grp) | |
271 | { | |
def31174 | 272 | genl_lock_all(); |
79dc4386 | 273 | __genl_unregister_mc_group(family, grp); |
def31174 | 274 | genl_unlock_all(); |
2dbba6f7 | 275 | } |
3efb40c2 | 276 | EXPORT_SYMBOL(genl_unregister_mc_group); |
2dbba6f7 JB |
277 | |
278 | static void genl_unregister_mc_groups(struct genl_family *family) | |
279 | { | |
280 | struct genl_multicast_group *grp, *tmp; | |
281 | ||
282 | list_for_each_entry_safe(grp, tmp, &family->mcast_groups, list) | |
79dc4386 | 283 | __genl_unregister_mc_group(family, grp); |
2dbba6f7 JB |
284 | } |
285 | ||
568508aa | 286 | static int genl_validate_ops(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 JB |
306 | /* family is not registered yet, so no locking needed */ |
307 | family->ops = ops; | |
308 | family->n_ops = n_ops; | |
482a8524 | 309 | |
d91824c0 | 310 | return 0; |
482a8524 | 311 | } |
482a8524 TG |
312 | |
313 | /** | |
33c6b1f6 | 314 | * __genl_register_family - register a generic netlink family |
482a8524 TG |
315 | * @family: generic netlink family |
316 | * | |
317 | * Registers the specified family after validating it first. Only one | |
318 | * family may be registered with the same family name or identifier. | |
319 | * The family id may equal GENL_ID_GENERATE causing an unique id to | |
320 | * be automatically generated and assigned. | |
321 | * | |
568508aa JB |
322 | * The family's ops array must already be assigned, you can use the |
323 | * genl_register_family_with_ops() helper function. | |
324 | * | |
482a8524 TG |
325 | * Return 0 on success or a negative error code. |
326 | */ | |
33c6b1f6 | 327 | int __genl_register_family(struct genl_family *family) |
482a8524 TG |
328 | { |
329 | int err = -EINVAL; | |
330 | ||
331 | if (family->id && family->id < GENL_MIN_ID) | |
332 | goto errout; | |
333 | ||
334 | if (family->id > GENL_MAX_ID) | |
335 | goto errout; | |
336 | ||
568508aa JB |
337 | err = genl_validate_ops(family); |
338 | if (err) | |
339 | return err; | |
340 | ||
2dbba6f7 | 341 | INIT_LIST_HEAD(&family->mcast_groups); |
482a8524 | 342 | |
def31174 | 343 | genl_lock_all(); |
482a8524 TG |
344 | |
345 | if (genl_family_find_byname(family->name)) { | |
346 | err = -EEXIST; | |
347 | goto errout_locked; | |
348 | } | |
349 | ||
482a8524 TG |
350 | if (family->id == GENL_ID_GENERATE) { |
351 | u16 newid = genl_generate_id(); | |
352 | ||
353 | if (!newid) { | |
354 | err = -ENOMEM; | |
355 | goto errout_locked; | |
356 | } | |
357 | ||
358 | family->id = newid; | |
93860b08 KK |
359 | } else if (genl_family_find_byid(family->id)) { |
360 | err = -EEXIST; | |
361 | goto errout_locked; | |
482a8524 TG |
362 | } |
363 | ||
def31174 | 364 | if (family->maxattr && !family->parallel_ops) { |
482a8524 TG |
365 | family->attrbuf = kmalloc((family->maxattr+1) * |
366 | sizeof(struct nlattr *), GFP_KERNEL); | |
367 | if (family->attrbuf == NULL) { | |
368 | err = -ENOMEM; | |
e200bd80 | 369 | goto errout_locked; |
482a8524 TG |
370 | } |
371 | } else | |
372 | family->attrbuf = NULL; | |
373 | ||
374 | list_add_tail(&family->family_list, genl_family_chain(family->id)); | |
def31174 | 375 | genl_unlock_all(); |
482a8524 TG |
376 | |
377 | genl_ctrl_event(CTRL_CMD_NEWFAMILY, family); | |
378 | ||
379 | return 0; | |
380 | ||
381 | errout_locked: | |
def31174 | 382 | genl_unlock_all(); |
482a8524 TG |
383 | errout: |
384 | return err; | |
385 | } | |
33c6b1f6 | 386 | EXPORT_SYMBOL(__genl_register_family); |
482a8524 TG |
387 | |
388 | /** | |
389 | * genl_unregister_family - unregister generic netlink family | |
390 | * @family: generic netlink family | |
391 | * | |
392 | * Unregisters the specified family. | |
393 | * | |
394 | * Returns 0 on success or a negative error code. | |
395 | */ | |
396 | int genl_unregister_family(struct genl_family *family) | |
397 | { | |
398 | struct genl_family *rc; | |
399 | ||
def31174 | 400 | genl_lock_all(); |
482a8524 | 401 | |
910d6c32 PE |
402 | genl_unregister_mc_groups(family); |
403 | ||
482a8524 TG |
404 | list_for_each_entry(rc, genl_family_chain(family->id), family_list) { |
405 | if (family->id != rc->id || strcmp(rc->name, family->name)) | |
406 | continue; | |
407 | ||
408 | list_del(&rc->family_list); | |
d91824c0 | 409 | family->n_ops = 0; |
def31174 | 410 | genl_unlock_all(); |
482a8524 | 411 | |
482a8524 TG |
412 | kfree(family->attrbuf); |
413 | genl_ctrl_event(CTRL_CMD_DELFAMILY, family); | |
414 | return 0; | |
415 | } | |
416 | ||
def31174 | 417 | genl_unlock_all(); |
482a8524 TG |
418 | |
419 | return -ENOENT; | |
420 | } | |
416c2f9c | 421 | EXPORT_SYMBOL(genl_unregister_family); |
482a8524 | 422 | |
a46621a3 DV |
423 | /** |
424 | * genlmsg_put - Add generic netlink header to netlink message | |
425 | * @skb: socket buffer holding the message | |
15e47304 | 426 | * @portid: netlink portid the message is addressed to |
a46621a3 DV |
427 | * @seq: sequence number (usually the one of the sender) |
428 | * @family: generic netlink family | |
2c53040f | 429 | * @flags: netlink message flags |
a46621a3 DV |
430 | * @cmd: generic netlink command |
431 | * | |
432 | * Returns pointer to user specific header | |
433 | */ | |
15e47304 | 434 | void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, |
a46621a3 DV |
435 | struct genl_family *family, int flags, u8 cmd) |
436 | { | |
437 | struct nlmsghdr *nlh; | |
438 | struct genlmsghdr *hdr; | |
439 | ||
15e47304 | 440 | nlh = nlmsg_put(skb, portid, seq, family->id, GENL_HDRLEN + |
a46621a3 DV |
441 | family->hdrsize, flags); |
442 | if (nlh == NULL) | |
443 | return NULL; | |
444 | ||
445 | hdr = nlmsg_data(nlh); | |
446 | hdr->cmd = cmd; | |
447 | hdr->version = family->version; | |
448 | hdr->reserved = 0; | |
449 | ||
450 | return (char *) hdr + GENL_HDRLEN; | |
451 | } | |
452 | EXPORT_SYMBOL(genlmsg_put); | |
453 | ||
9b96309c PS |
454 | static int genl_lock_dumpit(struct sk_buff *skb, struct netlink_callback *cb) |
455 | { | |
f84f771d JB |
456 | /* our ops are always const - netlink API doesn't propagate that */ |
457 | const struct genl_ops *ops = cb->data; | |
9b96309c PS |
458 | int rc; |
459 | ||
460 | genl_lock(); | |
461 | rc = ops->dumpit(skb, cb); | |
462 | genl_unlock(); | |
463 | return rc; | |
464 | } | |
465 | ||
466 | static int genl_lock_done(struct netlink_callback *cb) | |
467 | { | |
f84f771d JB |
468 | /* our ops are always const - netlink API doesn't propagate that */ |
469 | const struct genl_ops *ops = cb->data; | |
9b96309c PS |
470 | int rc = 0; |
471 | ||
472 | if (ops->done) { | |
473 | genl_lock(); | |
474 | rc = ops->done(cb); | |
475 | genl_unlock(); | |
476 | } | |
477 | return rc; | |
478 | } | |
479 | ||
def31174 PS |
480 | static int genl_family_rcv_msg(struct genl_family *family, |
481 | struct sk_buff *skb, | |
482 | struct nlmsghdr *nlh) | |
482a8524 | 483 | { |
f84f771d | 484 | const struct genl_ops *ops; |
134e6375 | 485 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
486 | struct genl_info info; |
487 | struct genlmsghdr *hdr = nlmsg_data(nlh); | |
def31174 | 488 | struct nlattr **attrbuf; |
1d00a4eb | 489 | int hdrlen, err; |
482a8524 | 490 | |
134e6375 JB |
491 | /* this family doesn't exist in this netns */ |
492 | if (!family->netnsok && !net_eq(net, &init_net)) | |
493 | return -ENOENT; | |
494 | ||
482a8524 TG |
495 | hdrlen = GENL_HDRLEN + family->hdrsize; |
496 | if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen)) | |
1d00a4eb | 497 | return -EINVAL; |
482a8524 TG |
498 | |
499 | ops = genl_get_cmd(hdr->cmd, family); | |
1d00a4eb TG |
500 | if (ops == NULL) |
501 | return -EOPNOTSUPP; | |
482a8524 | 502 | |
1d00a4eb | 503 | if ((ops->flags & GENL_ADMIN_PERM) && |
fd778461 | 504 | !capable(CAP_NET_ADMIN)) |
1d00a4eb | 505 | return -EPERM; |
482a8524 | 506 | |
e1ee3673 | 507 | if ((nlh->nlmsg_flags & NLM_F_DUMP) == NLM_F_DUMP) { |
9b96309c | 508 | int rc; |
def31174 | 509 | |
1d00a4eb TG |
510 | if (ops->dumpit == NULL) |
511 | return -EOPNOTSUPP; | |
482a8524 | 512 | |
9b96309c PS |
513 | if (!family->parallel_ops) { |
514 | struct netlink_dump_control c = { | |
33c6b1f6 | 515 | .module = family->module, |
f84f771d JB |
516 | /* we have const, but the netlink API doesn't */ |
517 | .data = (void *)ops, | |
9b96309c PS |
518 | .dump = genl_lock_dumpit, |
519 | .done = genl_lock_done, | |
520 | }; | |
521 | ||
522 | genl_unlock(); | |
33c6b1f6 | 523 | rc = __netlink_dump_start(net->genl_sock, skb, nlh, &c); |
9b96309c PS |
524 | genl_lock(); |
525 | ||
526 | } else { | |
527 | struct netlink_dump_control c = { | |
33c6b1f6 | 528 | .module = family->module, |
9b96309c PS |
529 | .dump = ops->dumpit, |
530 | .done = ops->done, | |
531 | }; | |
532 | ||
33c6b1f6 | 533 | rc = __netlink_dump_start(net->genl_sock, skb, nlh, &c); |
9b96309c PS |
534 | } |
535 | ||
536 | return rc; | |
482a8524 TG |
537 | } |
538 | ||
1d00a4eb TG |
539 | if (ops->doit == NULL) |
540 | return -EOPNOTSUPP; | |
482a8524 | 541 | |
def31174 PS |
542 | if (family->maxattr && family->parallel_ops) { |
543 | attrbuf = kmalloc((family->maxattr+1) * | |
544 | sizeof(struct nlattr *), GFP_KERNEL); | |
545 | if (attrbuf == NULL) | |
546 | return -ENOMEM; | |
547 | } else | |
548 | attrbuf = family->attrbuf; | |
549 | ||
550 | if (attrbuf) { | |
551 | err = nlmsg_parse(nlh, hdrlen, attrbuf, family->maxattr, | |
482a8524 TG |
552 | ops->policy); |
553 | if (err < 0) | |
50754d21 | 554 | goto out; |
482a8524 TG |
555 | } |
556 | ||
557 | info.snd_seq = nlh->nlmsg_seq; | |
15e47304 | 558 | info.snd_portid = NETLINK_CB(skb).portid; |
482a8524 TG |
559 | info.nlhdr = nlh; |
560 | info.genlhdr = nlmsg_data(nlh); | |
561 | info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN; | |
def31174 | 562 | info.attrs = attrbuf; |
134e6375 | 563 | genl_info_net_set(&info, net); |
ff4c92d8 | 564 | memset(&info.user_ptr, 0, sizeof(info.user_ptr)); |
482a8524 | 565 | |
ff4c92d8 JB |
566 | if (family->pre_doit) { |
567 | err = family->pre_doit(ops, skb, &info); | |
568 | if (err) | |
50754d21 | 569 | goto out; |
ff4c92d8 JB |
570 | } |
571 | ||
572 | err = ops->doit(skb, &info); | |
573 | ||
574 | if (family->post_doit) | |
575 | family->post_doit(ops, skb, &info); | |
576 | ||
50754d21 | 577 | out: |
def31174 PS |
578 | if (family->parallel_ops) |
579 | kfree(attrbuf); | |
580 | ||
581 | return err; | |
582 | } | |
583 | ||
584 | static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) | |
585 | { | |
586 | struct genl_family *family; | |
587 | int err; | |
588 | ||
589 | family = genl_family_find_byid(nlh->nlmsg_type); | |
590 | if (family == NULL) | |
591 | return -ENOENT; | |
592 | ||
593 | if (!family->parallel_ops) | |
594 | genl_lock(); | |
595 | ||
596 | err = genl_family_rcv_msg(family, skb, nlh); | |
597 | ||
598 | if (!family->parallel_ops) | |
599 | genl_unlock(); | |
600 | ||
ff4c92d8 | 601 | return err; |
482a8524 TG |
602 | } |
603 | ||
cd40b7d3 | 604 | static void genl_rcv(struct sk_buff *skb) |
482a8524 | 605 | { |
def31174 | 606 | down_read(&cb_lock); |
cd40b7d3 | 607 | netlink_rcv_skb(skb, &genl_rcv_msg); |
def31174 | 608 | up_read(&cb_lock); |
482a8524 TG |
609 | } |
610 | ||
611 | /************************************************************************** | |
612 | * Controller | |
613 | **************************************************************************/ | |
614 | ||
17c157c8 TG |
615 | static struct genl_family genl_ctrl = { |
616 | .id = GENL_ID_CTRL, | |
617 | .name = "nlctrl", | |
334c29a6 | 618 | .version = 0x2, |
17c157c8 | 619 | .maxattr = CTRL_ATTR_MAX, |
134e6375 | 620 | .netnsok = true, |
17c157c8 TG |
621 | }; |
622 | ||
15e47304 | 623 | static int ctrl_fill_info(struct genl_family *family, u32 portid, u32 seq, |
482a8524 TG |
624 | u32 flags, struct sk_buff *skb, u8 cmd) |
625 | { | |
626 | void *hdr; | |
627 | ||
15e47304 | 628 | hdr = genlmsg_put(skb, portid, seq, &genl_ctrl, flags, cmd); |
482a8524 TG |
629 | if (hdr == NULL) |
630 | return -1; | |
631 | ||
444653f6 DM |
632 | if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, family->name) || |
633 | nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, family->id) || | |
634 | nla_put_u32(skb, CTRL_ATTR_VERSION, family->version) || | |
635 | nla_put_u32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize) || | |
636 | nla_put_u32(skb, CTRL_ATTR_MAXATTR, family->maxattr)) | |
637 | goto nla_put_failure; | |
eb328111 | 638 | |
d91824c0 | 639 | if (family->n_ops) { |
e94ef682 | 640 | struct nlattr *nla_ops; |
d91824c0 | 641 | int i; |
eb328111 | 642 | |
e94ef682 TG |
643 | nla_ops = nla_nest_start(skb, CTRL_ATTR_OPS); |
644 | if (nla_ops == NULL) | |
eb328111 TG |
645 | goto nla_put_failure; |
646 | ||
d91824c0 | 647 | for (i = 0; i < family->n_ops; i++) { |
e94ef682 | 648 | struct nlattr *nest; |
f84f771d JB |
649 | const struct genl_ops *ops = &family->ops[i]; |
650 | u32 flags = ops->flags; | |
651 | ||
652 | if (ops->dumpit) | |
653 | flags |= GENL_CMD_CAP_DUMP; | |
654 | if (ops->doit) | |
655 | flags |= GENL_CMD_CAP_DO; | |
656 | if (ops->policy) | |
657 | flags |= GENL_CMD_CAP_HASPOL; | |
eb328111 | 658 | |
d91824c0 | 659 | nest = nla_nest_start(skb, i + 1); |
e94ef682 TG |
660 | if (nest == NULL) |
661 | goto nla_put_failure; | |
eb328111 | 662 | |
444653f6 | 663 | if (nla_put_u32(skb, CTRL_ATTR_OP_ID, ops->cmd) || |
f84f771d | 664 | nla_put_u32(skb, CTRL_ATTR_OP_FLAGS, flags)) |
444653f6 | 665 | goto nla_put_failure; |
eb328111 | 666 | |
e94ef682 TG |
667 | nla_nest_end(skb, nest); |
668 | } | |
669 | ||
670 | nla_nest_end(skb, nla_ops); | |
671 | } | |
482a8524 | 672 | |
2dbba6f7 JB |
673 | if (!list_empty(&family->mcast_groups)) { |
674 | struct genl_multicast_group *grp; | |
675 | struct nlattr *nla_grps; | |
676 | int idx = 1; | |
677 | ||
678 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
679 | if (nla_grps == NULL) | |
680 | goto nla_put_failure; | |
681 | ||
682 | list_for_each_entry(grp, &family->mcast_groups, list) { | |
683 | struct nlattr *nest; | |
684 | ||
685 | nest = nla_nest_start(skb, idx++); | |
686 | if (nest == NULL) | |
687 | goto nla_put_failure; | |
688 | ||
444653f6 DM |
689 | if (nla_put_u32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id) || |
690 | nla_put_string(skb, CTRL_ATTR_MCAST_GRP_NAME, | |
691 | grp->name)) | |
692 | goto nla_put_failure; | |
2dbba6f7 JB |
693 | |
694 | nla_nest_end(skb, nest); | |
695 | } | |
696 | nla_nest_end(skb, nla_grps); | |
697 | } | |
698 | ||
699 | return genlmsg_end(skb, hdr); | |
700 | ||
701 | nla_put_failure: | |
bc3ed28c TG |
702 | genlmsg_cancel(skb, hdr); |
703 | return -EMSGSIZE; | |
2dbba6f7 JB |
704 | } |
705 | ||
15e47304 | 706 | static int ctrl_fill_mcgrp_info(struct genl_multicast_group *grp, u32 portid, |
2dbba6f7 JB |
707 | u32 seq, u32 flags, struct sk_buff *skb, |
708 | u8 cmd) | |
709 | { | |
710 | void *hdr; | |
711 | struct nlattr *nla_grps; | |
712 | struct nlattr *nest; | |
713 | ||
15e47304 | 714 | hdr = genlmsg_put(skb, portid, seq, &genl_ctrl, flags, cmd); |
2dbba6f7 JB |
715 | if (hdr == NULL) |
716 | return -1; | |
717 | ||
444653f6 DM |
718 | if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, grp->family->name) || |
719 | nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, grp->family->id)) | |
720 | goto nla_put_failure; | |
2dbba6f7 JB |
721 | |
722 | nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS); | |
723 | if (nla_grps == NULL) | |
724 | goto nla_put_failure; | |
725 | ||
726 | nest = nla_nest_start(skb, 1); | |
727 | if (nest == NULL) | |
728 | goto nla_put_failure; | |
729 | ||
444653f6 DM |
730 | if (nla_put_u32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id) || |
731 | nla_put_string(skb, CTRL_ATTR_MCAST_GRP_NAME, | |
732 | grp->name)) | |
733 | goto nla_put_failure; | |
2dbba6f7 JB |
734 | |
735 | nla_nest_end(skb, nest); | |
736 | nla_nest_end(skb, nla_grps); | |
737 | ||
482a8524 TG |
738 | return genlmsg_end(skb, hdr); |
739 | ||
740 | nla_put_failure: | |
bc3ed28c TG |
741 | genlmsg_cancel(skb, hdr); |
742 | return -EMSGSIZE; | |
482a8524 TG |
743 | } |
744 | ||
745 | static int ctrl_dumpfamily(struct sk_buff *skb, struct netlink_callback *cb) | |
746 | { | |
747 | ||
748 | int i, n = 0; | |
749 | struct genl_family *rt; | |
134e6375 | 750 | struct net *net = sock_net(skb->sk); |
482a8524 TG |
751 | int chains_to_skip = cb->args[0]; |
752 | int fams_to_skip = cb->args[1]; | |
753 | ||
e1d5a010 | 754 | for (i = chains_to_skip; i < GENL_FAM_TAB_SIZE; i++) { |
482a8524 TG |
755 | n = 0; |
756 | list_for_each_entry(rt, genl_family_chain(i), family_list) { | |
134e6375 JB |
757 | if (!rt->netnsok && !net_eq(net, &init_net)) |
758 | continue; | |
482a8524 TG |
759 | if (++n < fams_to_skip) |
760 | continue; | |
15e47304 | 761 | if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).portid, |
482a8524 TG |
762 | cb->nlh->nlmsg_seq, NLM_F_MULTI, |
763 | skb, CTRL_CMD_NEWFAMILY) < 0) | |
764 | goto errout; | |
765 | } | |
766 | ||
767 | fams_to_skip = 0; | |
768 | } | |
769 | ||
770 | errout: | |
771 | cb->args[0] = i; | |
772 | cb->args[1] = n; | |
773 | ||
774 | return skb->len; | |
775 | } | |
776 | ||
2dbba6f7 | 777 | static struct sk_buff *ctrl_build_family_msg(struct genl_family *family, |
15e47304 | 778 | u32 portid, int seq, u8 cmd) |
482a8524 TG |
779 | { |
780 | struct sk_buff *skb; | |
781 | int err; | |
782 | ||
339bf98f | 783 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); |
482a8524 TG |
784 | if (skb == NULL) |
785 | return ERR_PTR(-ENOBUFS); | |
786 | ||
15e47304 | 787 | err = ctrl_fill_info(family, portid, seq, 0, skb, cmd); |
482a8524 TG |
788 | if (err < 0) { |
789 | nlmsg_free(skb); | |
790 | return ERR_PTR(err); | |
791 | } | |
792 | ||
793 | return skb; | |
794 | } | |
795 | ||
2dbba6f7 | 796 | static struct sk_buff *ctrl_build_mcgrp_msg(struct genl_multicast_group *grp, |
15e47304 | 797 | u32 portid, int seq, u8 cmd) |
2dbba6f7 JB |
798 | { |
799 | struct sk_buff *skb; | |
800 | int err; | |
801 | ||
802 | skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); | |
803 | if (skb == NULL) | |
804 | return ERR_PTR(-ENOBUFS); | |
805 | ||
15e47304 | 806 | err = ctrl_fill_mcgrp_info(grp, portid, seq, 0, skb, cmd); |
2dbba6f7 JB |
807 | if (err < 0) { |
808 | nlmsg_free(skb); | |
809 | return ERR_PTR(err); | |
810 | } | |
811 | ||
812 | return skb; | |
813 | } | |
814 | ||
ef7c79ed | 815 | static const struct nla_policy ctrl_policy[CTRL_ATTR_MAX+1] = { |
482a8524 | 816 | [CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 }, |
5176f91e TG |
817 | [CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING, |
818 | .len = GENL_NAMSIZ - 1 }, | |
482a8524 TG |
819 | }; |
820 | ||
821 | static int ctrl_getfamily(struct sk_buff *skb, struct genl_info *info) | |
822 | { | |
823 | struct sk_buff *msg; | |
824 | struct genl_family *res = NULL; | |
825 | int err = -EINVAL; | |
826 | ||
827 | if (info->attrs[CTRL_ATTR_FAMILY_ID]) { | |
828 | u16 id = nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]); | |
829 | res = genl_family_find_byid(id); | |
134e6375 | 830 | err = -ENOENT; |
482a8524 TG |
831 | } |
832 | ||
833 | if (info->attrs[CTRL_ATTR_FAMILY_NAME]) { | |
5176f91e | 834 | char *name; |
482a8524 | 835 | |
5176f91e | 836 | name = nla_data(info->attrs[CTRL_ATTR_FAMILY_NAME]); |
482a8524 | 837 | res = genl_family_find_byname(name); |
fa843095 SH |
838 | #ifdef CONFIG_MODULES |
839 | if (res == NULL) { | |
840 | genl_unlock(); | |
c74f2b26 | 841 | up_read(&cb_lock); |
e9412c37 | 842 | request_module("net-pf-%d-proto-%d-family-%s", |
fa843095 | 843 | PF_NETLINK, NETLINK_GENERIC, name); |
c74f2b26 | 844 | down_read(&cb_lock); |
fa843095 SH |
845 | genl_lock(); |
846 | res = genl_family_find_byname(name); | |
847 | } | |
848 | #endif | |
134e6375 | 849 | err = -ENOENT; |
482a8524 TG |
850 | } |
851 | ||
134e6375 JB |
852 | if (res == NULL) |
853 | return err; | |
854 | ||
855 | if (!res->netnsok && !net_eq(genl_info_net(info), &init_net)) { | |
856 | /* family doesn't exist here */ | |
857 | return -ENOENT; | |
482a8524 TG |
858 | } |
859 | ||
15e47304 | 860 | msg = ctrl_build_family_msg(res, info->snd_portid, info->snd_seq, |
2dbba6f7 | 861 | CTRL_CMD_NEWFAMILY); |
134e6375 JB |
862 | if (IS_ERR(msg)) |
863 | return PTR_ERR(msg); | |
482a8524 | 864 | |
134e6375 | 865 | return genlmsg_reply(msg, info); |
482a8524 TG |
866 | } |
867 | ||
868 | static int genl_ctrl_event(int event, void *data) | |
869 | { | |
870 | struct sk_buff *msg; | |
134e6375 JB |
871 | struct genl_family *family; |
872 | struct genl_multicast_group *grp; | |
482a8524 | 873 | |
134e6375 JB |
874 | /* genl is still initialising */ |
875 | if (!init_net.genl_sock) | |
482a8524 TG |
876 | return 0; |
877 | ||
878 | switch (event) { | |
879 | case CTRL_CMD_NEWFAMILY: | |
880 | case CTRL_CMD_DELFAMILY: | |
134e6375 JB |
881 | family = data; |
882 | msg = ctrl_build_family_msg(family, 0, 0, event); | |
2dbba6f7 JB |
883 | break; |
884 | case CTRL_CMD_NEWMCAST_GRP: | |
885 | case CTRL_CMD_DELMCAST_GRP: | |
134e6375 JB |
886 | grp = data; |
887 | family = grp->family; | |
2dbba6f7 | 888 | msg = ctrl_build_mcgrp_msg(data, 0, 0, event); |
482a8524 | 889 | break; |
134e6375 JB |
890 | default: |
891 | return -EINVAL; | |
892 | } | |
893 | ||
894 | if (IS_ERR(msg)) | |
895 | return PTR_ERR(msg); | |
896 | ||
897 | if (!family->netnsok) { | |
898 | genlmsg_multicast_netns(&init_net, msg, 0, | |
899 | GENL_ID_CTRL, GFP_KERNEL); | |
900 | } else { | |
901 | rcu_read_lock(); | |
902 | genlmsg_multicast_allns(msg, 0, GENL_ID_CTRL, GFP_ATOMIC); | |
903 | rcu_read_unlock(); | |
482a8524 TG |
904 | } |
905 | ||
906 | return 0; | |
907 | } | |
908 | ||
909 | static struct genl_ops genl_ctrl_ops = { | |
910 | .cmd = CTRL_CMD_GETFAMILY, | |
911 | .doit = ctrl_getfamily, | |
912 | .dumpit = ctrl_dumpfamily, | |
913 | .policy = ctrl_policy, | |
914 | }; | |
915 | ||
2dbba6f7 JB |
916 | static struct genl_multicast_group notify_grp = { |
917 | .name = "notify", | |
918 | }; | |
919 | ||
134e6375 JB |
920 | static int __net_init genl_pernet_init(struct net *net) |
921 | { | |
a31f2d17 PNA |
922 | struct netlink_kernel_cfg cfg = { |
923 | .input = genl_rcv, | |
9785e10a | 924 | .flags = NL_CFG_F_NONROOT_RECV, |
a31f2d17 PNA |
925 | }; |
926 | ||
134e6375 | 927 | /* we'll bump the group number right afterwards */ |
9f00d977 | 928 | net->genl_sock = netlink_kernel_create(net, NETLINK_GENERIC, &cfg); |
134e6375 JB |
929 | |
930 | if (!net->genl_sock && net_eq(net, &init_net)) | |
931 | panic("GENL: Cannot initialize generic netlink\n"); | |
932 | ||
933 | if (!net->genl_sock) | |
934 | return -ENOMEM; | |
935 | ||
936 | return 0; | |
937 | } | |
938 | ||
939 | static void __net_exit genl_pernet_exit(struct net *net) | |
940 | { | |
941 | netlink_kernel_release(net->genl_sock); | |
942 | net->genl_sock = NULL; | |
943 | } | |
944 | ||
945 | static struct pernet_operations genl_pernet_ops = { | |
946 | .init = genl_pernet_init, | |
947 | .exit = genl_pernet_exit, | |
948 | }; | |
949 | ||
482a8524 TG |
950 | static int __init genl_init(void) |
951 | { | |
952 | int i, err; | |
953 | ||
954 | for (i = 0; i < GENL_FAM_TAB_SIZE; i++) | |
955 | INIT_LIST_HEAD(&family_ht[i]); | |
956 | ||
652c6717 | 957 | err = genl_register_family_with_ops(&genl_ctrl, &genl_ctrl_ops, 1); |
482a8524 | 958 | if (err < 0) |
134e6375 | 959 | goto problem; |
482a8524 | 960 | |
134e6375 JB |
961 | err = register_pernet_subsys(&genl_pernet_ops); |
962 | if (err) | |
963 | goto problem; | |
482a8524 | 964 | |
2dbba6f7 JB |
965 | err = genl_register_mc_group(&genl_ctrl, ¬ify_grp); |
966 | if (err < 0) | |
134e6375 | 967 | goto problem; |
2dbba6f7 | 968 | |
482a8524 TG |
969 | return 0; |
970 | ||
134e6375 | 971 | problem: |
482a8524 | 972 | panic("GENL: Cannot register controller: %d\n", err); |
482a8524 TG |
973 | } |
974 | ||
975 | subsys_initcall(genl_init); | |
976 | ||
15e47304 | 977 | static int genlmsg_mcast(struct sk_buff *skb, u32 portid, unsigned long group, |
134e6375 JB |
978 | gfp_t flags) |
979 | { | |
980 | struct sk_buff *tmp; | |
981 | struct net *net, *prev = NULL; | |
982 | int err; | |
983 | ||
984 | for_each_net_rcu(net) { | |
985 | if (prev) { | |
986 | tmp = skb_clone(skb, flags); | |
987 | if (!tmp) { | |
988 | err = -ENOMEM; | |
989 | goto error; | |
990 | } | |
991 | err = nlmsg_multicast(prev->genl_sock, tmp, | |
15e47304 | 992 | portid, group, flags); |
134e6375 JB |
993 | if (err) |
994 | goto error; | |
995 | } | |
996 | ||
997 | prev = net; | |
998 | } | |
999 | ||
15e47304 | 1000 | return nlmsg_multicast(prev->genl_sock, skb, portid, group, flags); |
134e6375 JB |
1001 | error: |
1002 | kfree_skb(skb); | |
1003 | return err; | |
1004 | } | |
1005 | ||
15e47304 | 1006 | int genlmsg_multicast_allns(struct sk_buff *skb, u32 portid, unsigned int group, |
134e6375 JB |
1007 | gfp_t flags) |
1008 | { | |
15e47304 | 1009 | return genlmsg_mcast(skb, portid, group, flags); |
134e6375 JB |
1010 | } |
1011 | EXPORT_SYMBOL(genlmsg_multicast_allns); | |
263ba61d | 1012 | |
15e47304 | 1013 | void genl_notify(struct sk_buff *skb, struct net *net, u32 portid, u32 group, |
263ba61d PS |
1014 | struct nlmsghdr *nlh, gfp_t flags) |
1015 | { | |
1016 | struct sock *sk = net->genl_sock; | |
1017 | int report = 0; | |
1018 | ||
1019 | if (nlh) | |
1020 | report = nlmsg_report(nlh); | |
1021 | ||
15e47304 | 1022 | nlmsg_notify(sk, skb, portid, group, report, flags); |
263ba61d PS |
1023 | } |
1024 | EXPORT_SYMBOL(genl_notify); |