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Commit | Line | Data |
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f9e815b3 HW |
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> | |
67ca3966 | 6 | * (C) 2005,2007 by Pablo Neira Ayuso <pablo@netfilter.org> |
f9e815b3 HW |
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 | ||
f9e815b3 HW |
17 | #include <linux/module.h> |
18 | #include <linux/types.h> | |
19 | #include <linux/socket.h> | |
20 | #include <linux/kernel.h> | |
f9e815b3 HW |
21 | #include <linux/string.h> |
22 | #include <linux/sockios.h> | |
23 | #include <linux/net.h> | |
f9e815b3 HW |
24 | #include <linux/skbuff.h> |
25 | #include <asm/uaccess.h> | |
f9e815b3 HW |
26 | #include <net/sock.h> |
27 | #include <linux/init.h> | |
f9e815b3 | 28 | |
573ce260 | 29 | #include <net/netlink.h> |
f9e815b3 HW |
30 | #include <linux/netfilter/nfnetlink.h> |
31 | ||
32 | MODULE_LICENSE("GPL"); | |
4fdb3bb7 HW |
33 | MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>"); |
34 | MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_NETFILTER); | |
f9e815b3 HW |
35 | |
36 | static char __initdata nfversion[] = "0.30"; | |
37 | ||
c14b78e7 PNA |
38 | static struct { |
39 | struct mutex mutex; | |
40 | const struct nfnetlink_subsystem __rcu *subsys; | |
41 | } table[NFNL_SUBSYS_COUNT]; | |
f9e815b3 | 42 | |
03292745 PNA |
43 | static const int nfnl_group2type[NFNLGRP_MAX+1] = { |
44 | [NFNLGRP_CONNTRACK_NEW] = NFNL_SUBSYS_CTNETLINK, | |
45 | [NFNLGRP_CONNTRACK_UPDATE] = NFNL_SUBSYS_CTNETLINK, | |
46 | [NFNLGRP_CONNTRACK_DESTROY] = NFNL_SUBSYS_CTNETLINK, | |
47 | [NFNLGRP_CONNTRACK_EXP_NEW] = NFNL_SUBSYS_CTNETLINK_EXP, | |
48 | [NFNLGRP_CONNTRACK_EXP_UPDATE] = NFNL_SUBSYS_CTNETLINK_EXP, | |
49 | [NFNLGRP_CONNTRACK_EXP_DESTROY] = NFNL_SUBSYS_CTNETLINK_EXP, | |
97840cb6 PNA |
50 | [NFNLGRP_NFTABLES] = NFNL_SUBSYS_NFTABLES, |
51 | [NFNLGRP_ACCT_QUOTA] = NFNL_SUBSYS_ACCT, | |
03292745 PNA |
52 | }; |
53 | ||
c14b78e7 | 54 | void nfnl_lock(__u8 subsys_id) |
f9e815b3 | 55 | { |
c14b78e7 | 56 | mutex_lock(&table[subsys_id].mutex); |
f9e815b3 | 57 | } |
e6a7d3c0 | 58 | EXPORT_SYMBOL_GPL(nfnl_lock); |
f9e815b3 | 59 | |
c14b78e7 | 60 | void nfnl_unlock(__u8 subsys_id) |
a3c5029c | 61 | { |
c14b78e7 | 62 | mutex_unlock(&table[subsys_id].mutex); |
f9e815b3 | 63 | } |
e6a7d3c0 | 64 | EXPORT_SYMBOL_GPL(nfnl_unlock); |
f9e815b3 | 65 | |
0eb5db7a | 66 | #ifdef CONFIG_PROVE_LOCKING |
875e0829 | 67 | bool lockdep_nfnl_is_held(u8 subsys_id) |
0eb5db7a PM |
68 | { |
69 | return lockdep_is_held(&table[subsys_id].mutex); | |
70 | } | |
71 | EXPORT_SYMBOL_GPL(lockdep_nfnl_is_held); | |
72 | #endif | |
73 | ||
7c8d4cb4 | 74 | int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n) |
f9e815b3 | 75 | { |
c14b78e7 PNA |
76 | nfnl_lock(n->subsys_id); |
77 | if (table[n->subsys_id].subsys) { | |
78 | nfnl_unlock(n->subsys_id); | |
0ab43f84 HW |
79 | return -EBUSY; |
80 | } | |
c14b78e7 PNA |
81 | rcu_assign_pointer(table[n->subsys_id].subsys, n); |
82 | nfnl_unlock(n->subsys_id); | |
f9e815b3 HW |
83 | |
84 | return 0; | |
85 | } | |
f4bc177f | 86 | EXPORT_SYMBOL_GPL(nfnetlink_subsys_register); |
f9e815b3 | 87 | |
7c8d4cb4 | 88 | int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n) |
f9e815b3 | 89 | { |
c14b78e7 PNA |
90 | nfnl_lock(n->subsys_id); |
91 | table[n->subsys_id].subsys = NULL; | |
92 | nfnl_unlock(n->subsys_id); | |
6b75e3e8 | 93 | synchronize_rcu(); |
f9e815b3 HW |
94 | return 0; |
95 | } | |
f4bc177f | 96 | EXPORT_SYMBOL_GPL(nfnetlink_subsys_unregister); |
f9e815b3 | 97 | |
7c8d4cb4 | 98 | static inline const struct nfnetlink_subsystem *nfnetlink_get_subsys(u_int16_t type) |
f9e815b3 HW |
99 | { |
100 | u_int8_t subsys_id = NFNL_SUBSYS_ID(type); | |
101 | ||
ac0f1d98 | 102 | if (subsys_id >= NFNL_SUBSYS_COUNT) |
f9e815b3 HW |
103 | return NULL; |
104 | ||
c14b78e7 | 105 | return rcu_dereference(table[subsys_id].subsys); |
f9e815b3 HW |
106 | } |
107 | ||
7c8d4cb4 PM |
108 | static inline const struct nfnl_callback * |
109 | nfnetlink_find_client(u_int16_t type, const struct nfnetlink_subsystem *ss) | |
f9e815b3 HW |
110 | { |
111 | u_int8_t cb_id = NFNL_MSG_TYPE(type); | |
601e68e1 | 112 | |
67ca3966 | 113 | if (cb_id >= ss->cb_count) |
f9e815b3 | 114 | return NULL; |
f9e815b3 HW |
115 | |
116 | return &ss->cb[cb_id]; | |
117 | } | |
118 | ||
cd8c20b6 | 119 | int nfnetlink_has_listeners(struct net *net, unsigned int group) |
a2427692 | 120 | { |
cd8c20b6 | 121 | return netlink_has_listeners(net->nfnl, group); |
a2427692 PM |
122 | } |
123 | EXPORT_SYMBOL_GPL(nfnetlink_has_listeners); | |
124 | ||
3ab1f683 PM |
125 | struct sk_buff *nfnetlink_alloc_skb(struct net *net, unsigned int size, |
126 | u32 dst_portid, gfp_t gfp_mask) | |
127 | { | |
128 | return netlink_alloc_skb(net->nfnl, size, dst_portid, gfp_mask); | |
129 | } | |
130 | EXPORT_SYMBOL_GPL(nfnetlink_alloc_skb); | |
131 | ||
ec464e5d | 132 | int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 portid, |
95c96174 | 133 | unsigned int group, int echo, gfp_t flags) |
f9e815b3 | 134 | { |
ec464e5d | 135 | return nlmsg_notify(net->nfnl, skb, portid, group, echo, flags); |
f9e815b3 | 136 | } |
f4bc177f | 137 | EXPORT_SYMBOL_GPL(nfnetlink_send); |
f9e815b3 | 138 | |
ec464e5d | 139 | int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error) |
dd5b6ce6 | 140 | { |
ec464e5d | 141 | return netlink_set_err(net->nfnl, portid, group, error); |
dd5b6ce6 PNA |
142 | } |
143 | EXPORT_SYMBOL_GPL(nfnetlink_set_err); | |
144 | ||
ec464e5d PM |
145 | int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid, |
146 | int flags) | |
f9e815b3 | 147 | { |
ec464e5d | 148 | return netlink_unicast(net->nfnl, skb, portid, flags); |
f9e815b3 | 149 | } |
f4bc177f | 150 | EXPORT_SYMBOL_GPL(nfnetlink_unicast); |
f9e815b3 HW |
151 | |
152 | /* Process one complete nfnetlink message. */ | |
1d00a4eb | 153 | static int nfnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh) |
f9e815b3 | 154 | { |
cd8c20b6 | 155 | struct net *net = sock_net(skb->sk); |
7c8d4cb4 PM |
156 | const struct nfnl_callback *nc; |
157 | const struct nfnetlink_subsystem *ss; | |
1d00a4eb | 158 | int type, err; |
f9e815b3 | 159 | |
f9e815b3 | 160 | /* All the messages must at least contain nfgenmsg */ |
573ce260 | 161 | if (nlmsg_len(nlh) < sizeof(struct nfgenmsg)) |
f9e815b3 | 162 | return 0; |
f9e815b3 HW |
163 | |
164 | type = nlh->nlmsg_type; | |
e6a7d3c0 | 165 | replay: |
6b75e3e8 | 166 | rcu_read_lock(); |
f9e815b3 | 167 | ss = nfnetlink_get_subsys(type); |
0ab43f84 | 168 | if (!ss) { |
95a5afca | 169 | #ifdef CONFIG_MODULES |
6b75e3e8 | 170 | rcu_read_unlock(); |
37d2e7a2 | 171 | request_module("nfnetlink-subsys-%d", NFNL_SUBSYS_ID(type)); |
6b75e3e8 | 172 | rcu_read_lock(); |
37d2e7a2 | 173 | ss = nfnetlink_get_subsys(type); |
0ab43f84 HW |
174 | if (!ss) |
175 | #endif | |
6b75e3e8 ED |
176 | { |
177 | rcu_read_unlock(); | |
1d00a4eb | 178 | return -EINVAL; |
6b75e3e8 | 179 | } |
0ab43f84 | 180 | } |
f9e815b3 HW |
181 | |
182 | nc = nfnetlink_find_client(type, ss); | |
6b75e3e8 ED |
183 | if (!nc) { |
184 | rcu_read_unlock(); | |
1d00a4eb | 185 | return -EINVAL; |
6b75e3e8 | 186 | } |
f9e815b3 | 187 | |
f9e815b3 | 188 | { |
573ce260 | 189 | int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); |
e3730578 | 190 | u_int8_t cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type); |
f49c857f PNA |
191 | struct nlattr *cda[ss->cb[cb_id].attr_count + 1]; |
192 | struct nlattr *attr = (void *)nlh + min_len; | |
193 | int attrlen = nlh->nlmsg_len - min_len; | |
c14b78e7 | 194 | __u8 subsys_id = NFNL_SUBSYS_ID(type); |
f49c857f PNA |
195 | |
196 | err = nla_parse(cda, ss->cb[cb_id].attr_count, | |
197 | attr, attrlen, ss->cb[cb_id].policy); | |
4009e188 TB |
198 | if (err < 0) { |
199 | rcu_read_unlock(); | |
f49c857f | 200 | return err; |
4009e188 | 201 | } |
601e68e1 | 202 | |
6b75e3e8 ED |
203 | if (nc->call_rcu) { |
204 | err = nc->call_rcu(net->nfnl, skb, nlh, | |
205 | (const struct nlattr **)cda); | |
206 | rcu_read_unlock(); | |
207 | } else { | |
208 | rcu_read_unlock(); | |
c14b78e7 PNA |
209 | nfnl_lock(subsys_id); |
210 | if (rcu_dereference_protected(table[subsys_id].subsys, | |
9df9e783 | 211 | lockdep_is_held(&table[subsys_id].mutex)) != ss || |
6b75e3e8 ED |
212 | nfnetlink_find_client(type, ss) != nc) |
213 | err = -EAGAIN; | |
59560a38 | 214 | else if (nc->call) |
6b75e3e8 ED |
215 | err = nc->call(net->nfnl, skb, nlh, |
216 | (const struct nlattr **)cda); | |
59560a38 TB |
217 | else |
218 | err = -EINVAL; | |
c14b78e7 | 219 | nfnl_unlock(subsys_id); |
6b75e3e8 | 220 | } |
e6a7d3c0 PNA |
221 | if (err == -EAGAIN) |
222 | goto replay; | |
223 | return err; | |
f9e815b3 | 224 | } |
f9e815b3 HW |
225 | } |
226 | ||
cbb8125e PNA |
227 | struct nfnl_err { |
228 | struct list_head head; | |
229 | struct nlmsghdr *nlh; | |
230 | int err; | |
231 | }; | |
232 | ||
233 | static int nfnl_err_add(struct list_head *list, struct nlmsghdr *nlh, int err) | |
234 | { | |
235 | struct nfnl_err *nfnl_err; | |
236 | ||
237 | nfnl_err = kmalloc(sizeof(struct nfnl_err), GFP_KERNEL); | |
238 | if (nfnl_err == NULL) | |
239 | return -ENOMEM; | |
240 | ||
241 | nfnl_err->nlh = nlh; | |
242 | nfnl_err->err = err; | |
243 | list_add_tail(&nfnl_err->head, list); | |
244 | ||
245 | return 0; | |
246 | } | |
247 | ||
248 | static void nfnl_err_del(struct nfnl_err *nfnl_err) | |
249 | { | |
250 | list_del(&nfnl_err->head); | |
251 | kfree(nfnl_err); | |
252 | } | |
253 | ||
254 | static void nfnl_err_reset(struct list_head *err_list) | |
255 | { | |
256 | struct nfnl_err *nfnl_err, *next; | |
257 | ||
258 | list_for_each_entry_safe(nfnl_err, next, err_list, head) | |
259 | nfnl_err_del(nfnl_err); | |
260 | } | |
261 | ||
262 | static void nfnl_err_deliver(struct list_head *err_list, struct sk_buff *skb) | |
263 | { | |
264 | struct nfnl_err *nfnl_err, *next; | |
265 | ||
266 | list_for_each_entry_safe(nfnl_err, next, err_list, head) { | |
267 | netlink_ack(skb, nfnl_err->nlh, nfnl_err->err); | |
268 | nfnl_err_del(nfnl_err); | |
269 | } | |
270 | } | |
271 | ||
6742b9e3 PNA |
272 | enum { |
273 | NFNL_BATCH_FAILURE = (1 << 0), | |
274 | NFNL_BATCH_DONE = (1 << 1), | |
275 | NFNL_BATCH_REPLAY = (1 << 2), | |
276 | }; | |
277 | ||
0628b123 PNA |
278 | static void nfnetlink_rcv_batch(struct sk_buff *skb, struct nlmsghdr *nlh, |
279 | u_int16_t subsys_id) | |
280 | { | |
0f816232 | 281 | struct sk_buff *oskb = skb; |
0628b123 PNA |
282 | struct net *net = sock_net(skb->sk); |
283 | const struct nfnetlink_subsystem *ss; | |
284 | const struct nfnl_callback *nc; | |
cbb8125e | 285 | static LIST_HEAD(err_list); |
6742b9e3 | 286 | u32 status; |
0628b123 PNA |
287 | int err; |
288 | ||
289 | if (subsys_id >= NFNL_SUBSYS_COUNT) | |
290 | return netlink_ack(skb, nlh, -EINVAL); | |
291 | replay: | |
6742b9e3 PNA |
292 | status = 0; |
293 | ||
0f816232 DJ |
294 | skb = netlink_skb_clone(oskb, GFP_KERNEL); |
295 | if (!skb) | |
0628b123 PNA |
296 | return netlink_ack(oskb, nlh, -ENOMEM); |
297 | ||
0f816232 | 298 | skb->sk = oskb->sk; |
0628b123 PNA |
299 | |
300 | nfnl_lock(subsys_id); | |
301 | ss = rcu_dereference_protected(table[subsys_id].subsys, | |
302 | lockdep_is_held(&table[subsys_id].mutex)); | |
303 | if (!ss) { | |
304 | #ifdef CONFIG_MODULES | |
305 | nfnl_unlock(subsys_id); | |
306 | request_module("nfnetlink-subsys-%d", subsys_id); | |
307 | nfnl_lock(subsys_id); | |
308 | ss = rcu_dereference_protected(table[subsys_id].subsys, | |
309 | lockdep_is_held(&table[subsys_id].mutex)); | |
310 | if (!ss) | |
311 | #endif | |
312 | { | |
313 | nfnl_unlock(subsys_id); | |
ecd15dd7 | 314 | netlink_ack(skb, nlh, -EOPNOTSUPP); |
0f816232 | 315 | return kfree_skb(skb); |
0628b123 PNA |
316 | } |
317 | } | |
318 | ||
319 | if (!ss->commit || !ss->abort) { | |
320 | nfnl_unlock(subsys_id); | |
ecd15dd7 DF |
321 | netlink_ack(skb, nlh, -EOPNOTSUPP); |
322 | return kfree_skb(skb); | |
0628b123 PNA |
323 | } |
324 | ||
325 | while (skb->len >= nlmsg_total_size(0)) { | |
326 | int msglen, type; | |
327 | ||
328 | nlh = nlmsg_hdr(skb); | |
329 | err = 0; | |
330 | ||
9ea2aa8b PNA |
331 | if (nlmsg_len(nlh) < sizeof(struct nfgenmsg) || |
332 | skb->len < nlh->nlmsg_len) { | |
0628b123 PNA |
333 | err = -EINVAL; |
334 | goto ack; | |
335 | } | |
336 | ||
337 | /* Only requests are handled by the kernel */ | |
338 | if (!(nlh->nlmsg_flags & NLM_F_REQUEST)) { | |
339 | err = -EINVAL; | |
340 | goto ack; | |
341 | } | |
342 | ||
343 | type = nlh->nlmsg_type; | |
344 | if (type == NFNL_MSG_BATCH_BEGIN) { | |
345 | /* Malformed: Batch begin twice */ | |
cbb8125e | 346 | nfnl_err_reset(&err_list); |
6742b9e3 | 347 | status |= NFNL_BATCH_FAILURE; |
0628b123 PNA |
348 | goto done; |
349 | } else if (type == NFNL_MSG_BATCH_END) { | |
6742b9e3 | 350 | status |= NFNL_BATCH_DONE; |
0628b123 PNA |
351 | goto done; |
352 | } else if (type < NLMSG_MIN_TYPE) { | |
353 | err = -EINVAL; | |
354 | goto ack; | |
355 | } | |
356 | ||
357 | /* We only accept a batch with messages for the same | |
358 | * subsystem. | |
359 | */ | |
360 | if (NFNL_SUBSYS_ID(type) != subsys_id) { | |
361 | err = -EINVAL; | |
362 | goto ack; | |
363 | } | |
364 | ||
365 | nc = nfnetlink_find_client(type, ss); | |
366 | if (!nc) { | |
367 | err = -EINVAL; | |
368 | goto ack; | |
369 | } | |
370 | ||
371 | { | |
372 | int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); | |
373 | u_int8_t cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type); | |
374 | struct nlattr *cda[ss->cb[cb_id].attr_count + 1]; | |
375 | struct nlattr *attr = (void *)nlh + min_len; | |
376 | int attrlen = nlh->nlmsg_len - min_len; | |
377 | ||
378 | err = nla_parse(cda, ss->cb[cb_id].attr_count, | |
379 | attr, attrlen, ss->cb[cb_id].policy); | |
380 | if (err < 0) | |
381 | goto ack; | |
382 | ||
383 | if (nc->call_batch) { | |
384 | err = nc->call_batch(net->nfnl, skb, nlh, | |
385 | (const struct nlattr **)cda); | |
386 | } | |
387 | ||
388 | /* The lock was released to autoload some module, we | |
389 | * have to abort and start from scratch using the | |
390 | * original skb. | |
391 | */ | |
392 | if (err == -EAGAIN) { | |
6742b9e3 PNA |
393 | status |= NFNL_BATCH_REPLAY; |
394 | goto next; | |
0628b123 PNA |
395 | } |
396 | } | |
397 | ack: | |
398 | if (nlh->nlmsg_flags & NLM_F_ACK || err) { | |
cbb8125e PNA |
399 | /* Errors are delivered once the full batch has been |
400 | * processed, this avoids that the same error is | |
401 | * reported several times when replaying the batch. | |
402 | */ | |
403 | if (nfnl_err_add(&err_list, nlh, err) < 0) { | |
404 | /* We failed to enqueue an error, reset the | |
405 | * list of errors and send OOM to userspace | |
406 | * pointing to the batch header. | |
407 | */ | |
408 | nfnl_err_reset(&err_list); | |
409 | netlink_ack(skb, nlmsg_hdr(oskb), -ENOMEM); | |
6742b9e3 | 410 | status |= NFNL_BATCH_FAILURE; |
cbb8125e PNA |
411 | goto done; |
412 | } | |
0628b123 PNA |
413 | /* We don't stop processing the batch on errors, thus, |
414 | * userspace gets all the errors that the batch | |
415 | * triggers. | |
416 | */ | |
0628b123 | 417 | if (err) |
6742b9e3 | 418 | status |= NFNL_BATCH_FAILURE; |
0628b123 | 419 | } |
6742b9e3 | 420 | next: |
0628b123 PNA |
421 | msglen = NLMSG_ALIGN(nlh->nlmsg_len); |
422 | if (msglen > skb->len) | |
423 | msglen = skb->len; | |
424 | skb_pull(skb, msglen); | |
425 | } | |
426 | done: | |
6742b9e3 PNA |
427 | if (status & NFNL_BATCH_REPLAY) { |
428 | ss->abort(oskb); | |
429 | nfnl_err_reset(&err_list); | |
430 | nfnl_unlock(subsys_id); | |
431 | kfree_skb(skb); | |
432 | goto replay; | |
433 | } else if (status == NFNL_BATCH_DONE) { | |
fc04733a | 434 | ss->commit(oskb); |
6742b9e3 | 435 | } else { |
fc04733a | 436 | ss->abort(oskb); |
6742b9e3 | 437 | } |
0628b123 | 438 | |
cbb8125e | 439 | nfnl_err_deliver(&err_list, oskb); |
0628b123 | 440 | nfnl_unlock(subsys_id); |
0f816232 | 441 | kfree_skb(skb); |
0628b123 PNA |
442 | } |
443 | ||
cd40b7d3 | 444 | static void nfnetlink_rcv(struct sk_buff *skb) |
f9e815b3 | 445 | { |
0628b123 | 446 | struct nlmsghdr *nlh = nlmsg_hdr(skb); |
a9de9777 | 447 | u_int16_t res_id; |
0628b123 PNA |
448 | int msglen; |
449 | ||
0628b123 PNA |
450 | if (nlh->nlmsg_len < NLMSG_HDRLEN || |
451 | skb->len < nlh->nlmsg_len) | |
452 | return; | |
453 | ||
90f62cf3 | 454 | if (!netlink_net_capable(skb, CAP_NET_ADMIN)) { |
cdbe7c2d JB |
455 | netlink_ack(skb, nlh, -EPERM); |
456 | return; | |
457 | } | |
458 | ||
0628b123 PNA |
459 | if (nlh->nlmsg_type == NFNL_MSG_BATCH_BEGIN) { |
460 | struct nfgenmsg *nfgenmsg; | |
461 | ||
462 | msglen = NLMSG_ALIGN(nlh->nlmsg_len); | |
463 | if (msglen > skb->len) | |
464 | msglen = skb->len; | |
465 | ||
466 | if (nlh->nlmsg_len < NLMSG_HDRLEN || | |
467 | skb->len < NLMSG_HDRLEN + sizeof(struct nfgenmsg)) | |
468 | return; | |
469 | ||
470 | nfgenmsg = nlmsg_data(nlh); | |
471 | skb_pull(skb, msglen); | |
a9de9777 PNA |
472 | /* Work around old nft using host byte order */ |
473 | if (nfgenmsg->res_id == NFNL_SUBSYS_NFTABLES) | |
474 | res_id = NFNL_SUBSYS_NFTABLES; | |
475 | else | |
476 | res_id = ntohs(nfgenmsg->res_id); | |
477 | nfnetlink_rcv_batch(skb, nlh, res_id); | |
0628b123 PNA |
478 | } else { |
479 | netlink_rcv_skb(skb, &nfnetlink_rcv_msg); | |
480 | } | |
f9e815b3 HW |
481 | } |
482 | ||
03292745 | 483 | #ifdef CONFIG_MODULES |
023e2cfa | 484 | static int nfnetlink_bind(struct net *net, int group) |
03292745 PNA |
485 | { |
486 | const struct nfnetlink_subsystem *ss; | |
97840cb6 PNA |
487 | int type; |
488 | ||
489 | if (group <= NFNLGRP_NONE || group > NFNLGRP_MAX) | |
62924af2 | 490 | return 0; |
97840cb6 PNA |
491 | |
492 | type = nfnl_group2type[group]; | |
03292745 PNA |
493 | |
494 | rcu_read_lock(); | |
dbc3617f | 495 | ss = nfnetlink_get_subsys(type << 8); |
03292745 | 496 | rcu_read_unlock(); |
bfe4bc71 RGB |
497 | if (!ss) |
498 | request_module("nfnetlink-subsys-%d", type); | |
4f520900 | 499 | return 0; |
03292745 PNA |
500 | } |
501 | #endif | |
502 | ||
cd8c20b6 | 503 | static int __net_init nfnetlink_net_init(struct net *net) |
f9e815b3 | 504 | { |
cd8c20b6 | 505 | struct sock *nfnl; |
a31f2d17 PNA |
506 | struct netlink_kernel_cfg cfg = { |
507 | .groups = NFNLGRP_MAX, | |
508 | .input = nfnetlink_rcv, | |
03292745 PNA |
509 | #ifdef CONFIG_MODULES |
510 | .bind = nfnetlink_bind, | |
511 | #endif | |
a31f2d17 | 512 | }; |
cd8c20b6 | 513 | |
9f00d977 | 514 | nfnl = netlink_kernel_create(net, NETLINK_NETFILTER, &cfg); |
cd8c20b6 AD |
515 | if (!nfnl) |
516 | return -ENOMEM; | |
517 | net->nfnl_stash = nfnl; | |
cf778b00 | 518 | rcu_assign_pointer(net->nfnl, nfnl); |
cd8c20b6 | 519 | return 0; |
f9e815b3 HW |
520 | } |
521 | ||
cd8c20b6 | 522 | static void __net_exit nfnetlink_net_exit_batch(struct list_head *net_exit_list) |
f9e815b3 | 523 | { |
cd8c20b6 | 524 | struct net *net; |
f9e815b3 | 525 | |
cd8c20b6 | 526 | list_for_each_entry(net, net_exit_list, exit_list) |
a9b3cd7f | 527 | RCU_INIT_POINTER(net->nfnl, NULL); |
cd8c20b6 AD |
528 | synchronize_net(); |
529 | list_for_each_entry(net, net_exit_list, exit_list) | |
530 | netlink_kernel_release(net->nfnl_stash); | |
531 | } | |
f9e815b3 | 532 | |
cd8c20b6 AD |
533 | static struct pernet_operations nfnetlink_net_ops = { |
534 | .init = nfnetlink_net_init, | |
535 | .exit_batch = nfnetlink_net_exit_batch, | |
536 | }; | |
537 | ||
538 | static int __init nfnetlink_init(void) | |
539 | { | |
c14b78e7 PNA |
540 | int i; |
541 | ||
97840cb6 PNA |
542 | for (i = NFNLGRP_NONE + 1; i <= NFNLGRP_MAX; i++) |
543 | BUG_ON(nfnl_group2type[i] == NFNL_SUBSYS_NONE); | |
544 | ||
c14b78e7 PNA |
545 | for (i=0; i<NFNL_SUBSYS_COUNT; i++) |
546 | mutex_init(&table[i].mutex); | |
547 | ||
654d0fbd | 548 | pr_info("Netfilter messages via NETLINK v%s.\n", nfversion); |
cd8c20b6 | 549 | return register_pernet_subsys(&nfnetlink_net_ops); |
f9e815b3 HW |
550 | } |
551 | ||
cd8c20b6 AD |
552 | static void __exit nfnetlink_exit(void) |
553 | { | |
654d0fbd | 554 | pr_info("Removing netfilter NETLINK layer.\n"); |
cd8c20b6 AD |
555 | unregister_pernet_subsys(&nfnetlink_net_ops); |
556 | } | |
f9e815b3 HW |
557 | module_init(nfnetlink_init); |
558 | module_exit(nfnetlink_exit); |