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1 | /* Netfilter messages via netlink socket. Allows for user space | |
2 | * protocol helpers and general trouble making from userspace. | |
3 | * | |
4 | * (C) 2001 by Jay Schulist <jschlst@samba.org>, | |
5 | * (C) 2002-2005 by Harald Welte <laforge@gnumonks.org> | |
6 | * (C) 2005-2017 by Pablo Neira Ayuso <pablo@netfilter.org> | |
7 | * | |
8 | * Initial netfilter messages via netlink development funded and | |
9 | * generally made possible by Network Robots, Inc. (www.networkrobots.com) | |
10 | * | |
11 | * Further development of this code funded by Astaro AG (http://www.astaro.com) | |
12 | * | |
13 | * This software may be used and distributed according to the terms | |
14 | * of the GNU General Public License, incorporated herein by reference. | |
15 | */ | |
16 | ||
17 | #include <linux/module.h> | |
18 | #include <linux/types.h> | |
19 | #include <linux/socket.h> | |
20 | #include <linux/kernel.h> | |
21 | #include <linux/string.h> | |
22 | #include <linux/sockios.h> | |
23 | #include <linux/net.h> | |
24 | #include <linux/skbuff.h> | |
25 | #include <linux/uaccess.h> | |
26 | #include <net/sock.h> | |
27 | #include <linux/init.h> | |
28 | ||
29 | #include <net/netlink.h> | |
30 | #include <linux/netfilter/nfnetlink.h> | |
31 | ||
32 | MODULE_LICENSE("GPL"); | |
33 | MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>"); | |
34 | MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_NETFILTER); | |
35 | ||
36 | #define nfnl_dereference_protected(id) \ | |
37 | rcu_dereference_protected(table[(id)].subsys, \ | |
38 | lockdep_nfnl_is_held((id))) | |
39 | ||
40 | static char __initdata nfversion[] = "0.30"; | |
41 | ||
42 | static struct { | |
43 | struct mutex mutex; | |
44 | const struct nfnetlink_subsystem __rcu *subsys; | |
45 | } table[NFNL_SUBSYS_COUNT]; | |
46 | ||
47 | static const int nfnl_group2type[NFNLGRP_MAX+1] = { | |
48 | [NFNLGRP_CONNTRACK_NEW] = NFNL_SUBSYS_CTNETLINK, | |
49 | [NFNLGRP_CONNTRACK_UPDATE] = NFNL_SUBSYS_CTNETLINK, | |
50 | [NFNLGRP_CONNTRACK_DESTROY] = NFNL_SUBSYS_CTNETLINK, | |
51 | [NFNLGRP_CONNTRACK_EXP_NEW] = NFNL_SUBSYS_CTNETLINK_EXP, | |
52 | [NFNLGRP_CONNTRACK_EXP_UPDATE] = NFNL_SUBSYS_CTNETLINK_EXP, | |
53 | [NFNLGRP_CONNTRACK_EXP_DESTROY] = NFNL_SUBSYS_CTNETLINK_EXP, | |
54 | [NFNLGRP_NFTABLES] = NFNL_SUBSYS_NFTABLES, | |
55 | [NFNLGRP_ACCT_QUOTA] = NFNL_SUBSYS_ACCT, | |
56 | [NFNLGRP_NFTRACE] = NFNL_SUBSYS_NFTABLES, | |
57 | }; | |
58 | ||
59 | void nfnl_lock(__u8 subsys_id) | |
60 | { | |
61 | mutex_lock(&table[subsys_id].mutex); | |
62 | } | |
63 | EXPORT_SYMBOL_GPL(nfnl_lock); | |
64 | ||
65 | void nfnl_unlock(__u8 subsys_id) | |
66 | { | |
67 | mutex_unlock(&table[subsys_id].mutex); | |
68 | } | |
69 | EXPORT_SYMBOL_GPL(nfnl_unlock); | |
70 | ||
71 | #ifdef CONFIG_PROVE_LOCKING | |
72 | bool lockdep_nfnl_is_held(u8 subsys_id) | |
73 | { | |
74 | return lockdep_is_held(&table[subsys_id].mutex); | |
75 | } | |
76 | EXPORT_SYMBOL_GPL(lockdep_nfnl_is_held); | |
77 | #endif | |
78 | ||
79 | int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n) | |
80 | { | |
81 | nfnl_lock(n->subsys_id); | |
82 | if (table[n->subsys_id].subsys) { | |
83 | nfnl_unlock(n->subsys_id); | |
84 | return -EBUSY; | |
85 | } | |
86 | rcu_assign_pointer(table[n->subsys_id].subsys, n); | |
87 | nfnl_unlock(n->subsys_id); | |
88 | ||
89 | return 0; | |
90 | } | |
91 | EXPORT_SYMBOL_GPL(nfnetlink_subsys_register); | |
92 | ||
93 | int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n) | |
94 | { | |
95 | nfnl_lock(n->subsys_id); | |
96 | table[n->subsys_id].subsys = NULL; | |
97 | nfnl_unlock(n->subsys_id); | |
98 | synchronize_rcu(); | |
99 | return 0; | |
100 | } | |
101 | EXPORT_SYMBOL_GPL(nfnetlink_subsys_unregister); | |
102 | ||
103 | static inline const struct nfnetlink_subsystem *nfnetlink_get_subsys(u16 type) | |
104 | { | |
105 | u8 subsys_id = NFNL_SUBSYS_ID(type); | |
106 | ||
107 | if (subsys_id >= NFNL_SUBSYS_COUNT) | |
108 | return NULL; | |
109 | ||
110 | return rcu_dereference(table[subsys_id].subsys); | |
111 | } | |
112 | ||
113 | static inline const struct nfnl_callback * | |
114 | nfnetlink_find_client(u16 type, const struct nfnetlink_subsystem *ss) | |
115 | { | |
116 | u8 cb_id = NFNL_MSG_TYPE(type); | |
117 | ||
118 | if (cb_id >= ss->cb_count) | |
119 | return NULL; | |
120 | ||
121 | return &ss->cb[cb_id]; | |
122 | } | |
123 | ||
124 | int nfnetlink_has_listeners(struct net *net, unsigned int group) | |
125 | { | |
126 | return netlink_has_listeners(net->nfnl, group); | |
127 | } | |
128 | EXPORT_SYMBOL_GPL(nfnetlink_has_listeners); | |
129 | ||
130 | int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 portid, | |
131 | unsigned int group, int echo, gfp_t flags) | |
132 | { | |
133 | return nlmsg_notify(net->nfnl, skb, portid, group, echo, flags); | |
134 | } | |
135 | EXPORT_SYMBOL_GPL(nfnetlink_send); | |
136 | ||
137 | int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error) | |
138 | { | |
139 | return netlink_set_err(net->nfnl, portid, group, error); | |
140 | } | |
141 | EXPORT_SYMBOL_GPL(nfnetlink_set_err); | |
142 | ||
143 | int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid, | |
144 | int flags) | |
145 | { | |
146 | return netlink_unicast(net->nfnl, skb, portid, flags); | |
147 | } | |
148 | EXPORT_SYMBOL_GPL(nfnetlink_unicast); | |
149 | ||
150 | /* Process one complete nfnetlink message. */ | |
151 | static int nfnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) | |
152 | { | |
153 | struct net *net = sock_net(skb->sk); | |
154 | const struct nfnl_callback *nc; | |
155 | const struct nfnetlink_subsystem *ss; | |
156 | int type, err; | |
157 | ||
158 | /* All the messages must at least contain nfgenmsg */ | |
159 | if (nlmsg_len(nlh) < sizeof(struct nfgenmsg)) | |
160 | return 0; | |
161 | ||
162 | type = nlh->nlmsg_type; | |
163 | replay: | |
164 | rcu_read_lock(); | |
165 | ss = nfnetlink_get_subsys(type); | |
166 | if (!ss) { | |
167 | #ifdef CONFIG_MODULES | |
168 | rcu_read_unlock(); | |
169 | request_module("nfnetlink-subsys-%d", NFNL_SUBSYS_ID(type)); | |
170 | rcu_read_lock(); | |
171 | ss = nfnetlink_get_subsys(type); | |
172 | if (!ss) | |
173 | #endif | |
174 | { | |
175 | rcu_read_unlock(); | |
176 | return -EINVAL; | |
177 | } | |
178 | } | |
179 | ||
180 | nc = nfnetlink_find_client(type, ss); | |
181 | if (!nc) { | |
182 | rcu_read_unlock(); | |
183 | return -EINVAL; | |
184 | } | |
185 | ||
186 | { | |
187 | int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); | |
188 | u8 cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type); | |
189 | struct nlattr *cda[ss->cb[cb_id].attr_count + 1]; | |
190 | struct nlattr *attr = (void *)nlh + min_len; | |
191 | int attrlen = nlh->nlmsg_len - min_len; | |
192 | __u8 subsys_id = NFNL_SUBSYS_ID(type); | |
193 | ||
194 | err = nla_parse(cda, ss->cb[cb_id].attr_count, | |
195 | attr, attrlen, ss->cb[cb_id].policy); | |
196 | if (err < 0) { | |
197 | rcu_read_unlock(); | |
198 | return err; | |
199 | } | |
200 | ||
201 | if (nc->call_rcu) { | |
202 | err = nc->call_rcu(net, net->nfnl, skb, nlh, | |
203 | (const struct nlattr **)cda); | |
204 | rcu_read_unlock(); | |
205 | } else { | |
206 | rcu_read_unlock(); | |
207 | nfnl_lock(subsys_id); | |
208 | if (nfnl_dereference_protected(subsys_id) != ss || | |
209 | nfnetlink_find_client(type, ss) != nc) | |
210 | err = -EAGAIN; | |
211 | else if (nc->call) | |
212 | err = nc->call(net, net->nfnl, skb, nlh, | |
213 | (const struct nlattr **)cda); | |
214 | else | |
215 | err = -EINVAL; | |
216 | nfnl_unlock(subsys_id); | |
217 | } | |
218 | if (err == -EAGAIN) | |
219 | goto replay; | |
220 | return err; | |
221 | } | |
222 | } | |
223 | ||
224 | struct nfnl_err { | |
225 | struct list_head head; | |
226 | struct nlmsghdr *nlh; | |
227 | int err; | |
228 | }; | |
229 | ||
230 | static int nfnl_err_add(struct list_head *list, struct nlmsghdr *nlh, int err) | |
231 | { | |
232 | struct nfnl_err *nfnl_err; | |
233 | ||
234 | nfnl_err = kmalloc(sizeof(struct nfnl_err), GFP_KERNEL); | |
235 | if (nfnl_err == NULL) | |
236 | return -ENOMEM; | |
237 | ||
238 | nfnl_err->nlh = nlh; | |
239 | nfnl_err->err = err; | |
240 | list_add_tail(&nfnl_err->head, list); | |
241 | ||
242 | return 0; | |
243 | } | |
244 | ||
245 | static void nfnl_err_del(struct nfnl_err *nfnl_err) | |
246 | { | |
247 | list_del(&nfnl_err->head); | |
248 | kfree(nfnl_err); | |
249 | } | |
250 | ||
251 | static void nfnl_err_reset(struct list_head *err_list) | |
252 | { | |
253 | struct nfnl_err *nfnl_err, *next; | |
254 | ||
255 | list_for_each_entry_safe(nfnl_err, next, err_list, head) | |
256 | nfnl_err_del(nfnl_err); | |
257 | } | |
258 | ||
259 | static void nfnl_err_deliver(struct list_head *err_list, struct sk_buff *skb) | |
260 | { | |
261 | struct nfnl_err *nfnl_err, *next; | |
262 | ||
263 | list_for_each_entry_safe(nfnl_err, next, err_list, head) { | |
264 | netlink_ack(skb, nfnl_err->nlh, nfnl_err->err); | |
265 | nfnl_err_del(nfnl_err); | |
266 | } | |
267 | } | |
268 | ||
269 | enum { | |
270 | NFNL_BATCH_FAILURE = (1 << 0), | |
271 | NFNL_BATCH_DONE = (1 << 1), | |
272 | NFNL_BATCH_REPLAY = (1 << 2), | |
273 | }; | |
274 | ||
275 | static void nfnetlink_rcv_batch(struct sk_buff *skb, struct nlmsghdr *nlh, | |
276 | u16 subsys_id, u32 genid) | |
277 | { | |
278 | struct sk_buff *oskb = skb; | |
279 | struct net *net = sock_net(skb->sk); | |
280 | const struct nfnetlink_subsystem *ss; | |
281 | const struct nfnl_callback *nc; | |
282 | LIST_HEAD(err_list); | |
283 | u32 status; | |
284 | int err; | |
285 | ||
286 | if (subsys_id >= NFNL_SUBSYS_COUNT) | |
287 | return netlink_ack(skb, nlh, -EINVAL); | |
288 | replay: | |
289 | status = 0; | |
290 | ||
291 | skb = netlink_skb_clone(oskb, GFP_KERNEL); | |
292 | if (!skb) | |
293 | return netlink_ack(oskb, nlh, -ENOMEM); | |
294 | ||
295 | nfnl_lock(subsys_id); | |
296 | ss = nfnl_dereference_protected(subsys_id); | |
297 | if (!ss) { | |
298 | #ifdef CONFIG_MODULES | |
299 | nfnl_unlock(subsys_id); | |
300 | request_module("nfnetlink-subsys-%d", subsys_id); | |
301 | nfnl_lock(subsys_id); | |
302 | ss = nfnl_dereference_protected(subsys_id); | |
303 | if (!ss) | |
304 | #endif | |
305 | { | |
306 | nfnl_unlock(subsys_id); | |
307 | netlink_ack(oskb, nlh, -EOPNOTSUPP); | |
308 | return kfree_skb(skb); | |
309 | } | |
310 | } | |
311 | ||
312 | if (!ss->commit || !ss->abort) { | |
313 | nfnl_unlock(subsys_id); | |
314 | netlink_ack(oskb, nlh, -EOPNOTSUPP); | |
315 | return kfree_skb(skb); | |
316 | } | |
317 | ||
318 | if (genid && ss->valid_genid && !ss->valid_genid(net, genid)) { | |
319 | nfnl_unlock(subsys_id); | |
320 | netlink_ack(oskb, nlh, -ERESTART); | |
321 | return kfree_skb(skb); | |
322 | } | |
323 | ||
324 | while (skb->len >= nlmsg_total_size(0)) { | |
325 | int msglen, type; | |
326 | ||
327 | nlh = nlmsg_hdr(skb); | |
328 | err = 0; | |
329 | ||
330 | if (nlh->nlmsg_len < NLMSG_HDRLEN || | |
331 | skb->len < nlh->nlmsg_len || | |
332 | nlmsg_len(nlh) < sizeof(struct nfgenmsg)) { | |
333 | nfnl_err_reset(&err_list); | |
334 | status |= NFNL_BATCH_FAILURE; | |
335 | goto done; | |
336 | } | |
337 | ||
338 | /* Only requests are handled by the kernel */ | |
339 | if (!(nlh->nlmsg_flags & NLM_F_REQUEST)) { | |
340 | err = -EINVAL; | |
341 | goto ack; | |
342 | } | |
343 | ||
344 | type = nlh->nlmsg_type; | |
345 | if (type == NFNL_MSG_BATCH_BEGIN) { | |
346 | /* Malformed: Batch begin twice */ | |
347 | nfnl_err_reset(&err_list); | |
348 | status |= NFNL_BATCH_FAILURE; | |
349 | goto done; | |
350 | } else if (type == NFNL_MSG_BATCH_END) { | |
351 | status |= NFNL_BATCH_DONE; | |
352 | goto done; | |
353 | } else if (type < NLMSG_MIN_TYPE) { | |
354 | err = -EINVAL; | |
355 | goto ack; | |
356 | } | |
357 | ||
358 | /* We only accept a batch with messages for the same | |
359 | * subsystem. | |
360 | */ | |
361 | if (NFNL_SUBSYS_ID(type) != subsys_id) { | |
362 | err = -EINVAL; | |
363 | goto ack; | |
364 | } | |
365 | ||
366 | nc = nfnetlink_find_client(type, ss); | |
367 | if (!nc) { | |
368 | err = -EINVAL; | |
369 | goto ack; | |
370 | } | |
371 | ||
372 | { | |
373 | int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); | |
374 | u8 cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type); | |
375 | struct nlattr *cda[ss->cb[cb_id].attr_count + 1]; | |
376 | struct nlattr *attr = (void *)nlh + min_len; | |
377 | int attrlen = nlh->nlmsg_len - min_len; | |
378 | ||
379 | err = nla_parse(cda, ss->cb[cb_id].attr_count, | |
380 | attr, attrlen, ss->cb[cb_id].policy); | |
381 | if (err < 0) | |
382 | goto ack; | |
383 | ||
384 | if (nc->call_batch) { | |
385 | err = nc->call_batch(net, net->nfnl, skb, nlh, | |
386 | (const struct nlattr **)cda); | |
387 | } | |
388 | ||
389 | /* The lock was released to autoload some module, we | |
390 | * have to abort and start from scratch using the | |
391 | * original skb. | |
392 | */ | |
393 | if (err == -EAGAIN) { | |
394 | status |= NFNL_BATCH_REPLAY; | |
395 | goto next; | |
396 | } | |
397 | } | |
398 | ack: | |
399 | if (nlh->nlmsg_flags & NLM_F_ACK || err) { | |
400 | /* Errors are delivered once the full batch has been | |
401 | * processed, this avoids that the same error is | |
402 | * reported several times when replaying the batch. | |
403 | */ | |
404 | if (nfnl_err_add(&err_list, nlh, err) < 0) { | |
405 | /* We failed to enqueue an error, reset the | |
406 | * list of errors and send OOM to userspace | |
407 | * pointing to the batch header. | |
408 | */ | |
409 | nfnl_err_reset(&err_list); | |
410 | netlink_ack(oskb, nlmsg_hdr(oskb), -ENOMEM); | |
411 | status |= NFNL_BATCH_FAILURE; | |
412 | goto done; | |
413 | } | |
414 | /* We don't stop processing the batch on errors, thus, | |
415 | * userspace gets all the errors that the batch | |
416 | * triggers. | |
417 | */ | |
418 | if (err) | |
419 | status |= NFNL_BATCH_FAILURE; | |
420 | } | |
421 | next: | |
422 | msglen = NLMSG_ALIGN(nlh->nlmsg_len); | |
423 | if (msglen > skb->len) | |
424 | msglen = skb->len; | |
425 | skb_pull(skb, msglen); | |
426 | } | |
427 | done: | |
428 | if (status & NFNL_BATCH_REPLAY) { | |
429 | ss->abort(net, oskb); | |
430 | nfnl_err_reset(&err_list); | |
431 | nfnl_unlock(subsys_id); | |
432 | kfree_skb(skb); | |
433 | goto replay; | |
434 | } else if (status == NFNL_BATCH_DONE) { | |
435 | ss->commit(net, oskb); | |
436 | } else { | |
437 | ss->abort(net, oskb); | |
438 | } | |
439 | ||
440 | nfnl_err_deliver(&err_list, oskb); | |
441 | nfnl_unlock(subsys_id); | |
442 | kfree_skb(skb); | |
443 | } | |
444 | ||
445 | static const struct nla_policy nfnl_batch_policy[NFNL_BATCH_MAX + 1] = { | |
446 | [NFNL_BATCH_GENID] = { .type = NLA_U32 }, | |
447 | }; | |
448 | ||
449 | static void nfnetlink_rcv_skb_batch(struct sk_buff *skb, struct nlmsghdr *nlh) | |
450 | { | |
451 | int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); | |
452 | struct nlattr *attr = (void *)nlh + min_len; | |
453 | struct nlattr *cda[NFNL_BATCH_MAX + 1]; | |
454 | int attrlen = nlh->nlmsg_len - min_len; | |
455 | struct nfgenmsg *nfgenmsg; | |
456 | int msglen, err; | |
457 | u32 gen_id = 0; | |
458 | u16 res_id; | |
459 | ||
460 | msglen = NLMSG_ALIGN(nlh->nlmsg_len); | |
461 | if (msglen > skb->len) | |
462 | msglen = skb->len; | |
463 | ||
464 | if (nlh->nlmsg_len < NLMSG_HDRLEN || | |
465 | skb->len < NLMSG_HDRLEN + sizeof(struct nfgenmsg)) | |
466 | return; | |
467 | ||
468 | err = nla_parse(cda, NFNL_BATCH_MAX, attr, attrlen, nfnl_batch_policy); | |
469 | if (err < 0) { | |
470 | netlink_ack(skb, nlh, err); | |
471 | return; | |
472 | } | |
473 | if (cda[NFNL_BATCH_GENID]) | |
474 | gen_id = ntohl(nla_get_be32(cda[NFNL_BATCH_GENID])); | |
475 | ||
476 | nfgenmsg = nlmsg_data(nlh); | |
477 | skb_pull(skb, msglen); | |
478 | /* Work around old nft using host byte order */ | |
479 | if (nfgenmsg->res_id == NFNL_SUBSYS_NFTABLES) | |
480 | res_id = NFNL_SUBSYS_NFTABLES; | |
481 | else | |
482 | res_id = ntohs(nfgenmsg->res_id); | |
483 | ||
484 | nfnetlink_rcv_batch(skb, nlh, res_id, gen_id); | |
485 | } | |
486 | ||
487 | static void nfnetlink_rcv(struct sk_buff *skb) | |
488 | { | |
489 | struct nlmsghdr *nlh = nlmsg_hdr(skb); | |
490 | ||
491 | if (nlh->nlmsg_len < NLMSG_HDRLEN || | |
492 | skb->len < nlh->nlmsg_len) | |
493 | return; | |
494 | ||
495 | if (!netlink_net_capable(skb, CAP_NET_ADMIN)) { | |
496 | netlink_ack(skb, nlh, -EPERM); | |
497 | return; | |
498 | } | |
499 | ||
500 | if (nlh->nlmsg_type == NFNL_MSG_BATCH_BEGIN) | |
501 | nfnetlink_rcv_skb_batch(skb, nlh); | |
502 | else | |
503 | netlink_rcv_skb(skb, &nfnetlink_rcv_msg); | |
504 | } | |
505 | ||
506 | #ifdef CONFIG_MODULES | |
507 | static int nfnetlink_bind(struct net *net, int group) | |
508 | { | |
509 | const struct nfnetlink_subsystem *ss; | |
510 | int type; | |
511 | ||
512 | if (group <= NFNLGRP_NONE || group > NFNLGRP_MAX) | |
513 | return 0; | |
514 | ||
515 | type = nfnl_group2type[group]; | |
516 | ||
517 | rcu_read_lock(); | |
518 | ss = nfnetlink_get_subsys(type << 8); | |
519 | rcu_read_unlock(); | |
520 | if (!ss) | |
521 | request_module("nfnetlink-subsys-%d", type); | |
522 | return 0; | |
523 | } | |
524 | #endif | |
525 | ||
526 | static int __net_init nfnetlink_net_init(struct net *net) | |
527 | { | |
528 | struct sock *nfnl; | |
529 | struct netlink_kernel_cfg cfg = { | |
530 | .groups = NFNLGRP_MAX, | |
531 | .input = nfnetlink_rcv, | |
532 | #ifdef CONFIG_MODULES | |
533 | .bind = nfnetlink_bind, | |
534 | #endif | |
535 | }; | |
536 | ||
537 | nfnl = netlink_kernel_create(net, NETLINK_NETFILTER, &cfg); | |
538 | if (!nfnl) | |
539 | return -ENOMEM; | |
540 | net->nfnl_stash = nfnl; | |
541 | rcu_assign_pointer(net->nfnl, nfnl); | |
542 | return 0; | |
543 | } | |
544 | ||
545 | static void __net_exit nfnetlink_net_exit_batch(struct list_head *net_exit_list) | |
546 | { | |
547 | struct net *net; | |
548 | ||
549 | list_for_each_entry(net, net_exit_list, exit_list) | |
550 | RCU_INIT_POINTER(net->nfnl, NULL); | |
551 | synchronize_net(); | |
552 | list_for_each_entry(net, net_exit_list, exit_list) | |
553 | netlink_kernel_release(net->nfnl_stash); | |
554 | } | |
555 | ||
556 | static struct pernet_operations nfnetlink_net_ops = { | |
557 | .init = nfnetlink_net_init, | |
558 | .exit_batch = nfnetlink_net_exit_batch, | |
559 | }; | |
560 | ||
561 | static int __init nfnetlink_init(void) | |
562 | { | |
563 | int i; | |
564 | ||
565 | for (i = NFNLGRP_NONE + 1; i <= NFNLGRP_MAX; i++) | |
566 | BUG_ON(nfnl_group2type[i] == NFNL_SUBSYS_NONE); | |
567 | ||
568 | for (i=0; i<NFNL_SUBSYS_COUNT; i++) | |
569 | mutex_init(&table[i].mutex); | |
570 | ||
571 | pr_info("Netfilter messages via NETLINK v%s.\n", nfversion); | |
572 | return register_pernet_subsys(&nfnetlink_net_ops); | |
573 | } | |
574 | ||
575 | static void __exit nfnetlink_exit(void) | |
576 | { | |
577 | pr_info("Removing netfilter NETLINK layer.\n"); | |
578 | unregister_pernet_subsys(&nfnetlink_net_ops); | |
579 | } | |
580 | module_init(nfnetlink_init); | |
581 | module_exit(nfnetlink_exit); |