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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> | |
8c4d4e8b | 6 | * (C) 2005-2017 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 | 24 | #include <linux/skbuff.h> |
7c0f6ba6 | 25 | #include <linux/uaccess.h> |
f9e815b3 HW |
26 | #include <net/sock.h> |
27 | #include <linux/init.h> | |
8a3d4c36 | 28 | #include <linux/sched/signal.h> |
f9e815b3 | 29 | |
573ce260 | 30 | #include <net/netlink.h> |
f9e815b3 HW |
31 | #include <linux/netfilter/nfnetlink.h> |
32 | ||
33 | MODULE_LICENSE("GPL"); | |
4fdb3bb7 HW |
34 | MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>"); |
35 | MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_NETFILTER); | |
4cacc395 | 36 | MODULE_DESCRIPTION("Netfilter messages via netlink socket"); |
f9e815b3 | 37 | |
9c55d3b5 FW |
38 | #define nfnl_dereference_protected(id) \ |
39 | rcu_dereference_protected(table[(id)].subsys, \ | |
40 | lockdep_nfnl_is_held((id))) | |
41 | ||
7b7744e2 KC |
42 | #define NFNL_MAX_ATTR_COUNT 32 |
43 | ||
c14b78e7 PNA |
44 | static struct { |
45 | struct mutex mutex; | |
46 | const struct nfnetlink_subsystem __rcu *subsys; | |
47 | } table[NFNL_SUBSYS_COUNT]; | |
f9e815b3 | 48 | |
ab6c41ee FW |
49 | static struct lock_class_key nfnl_lockdep_keys[NFNL_SUBSYS_COUNT]; |
50 | ||
51 | static const char *const nfnl_lockdep_names[NFNL_SUBSYS_COUNT] = { | |
52 | [NFNL_SUBSYS_NONE] = "nfnl_subsys_none", | |
53 | [NFNL_SUBSYS_CTNETLINK] = "nfnl_subsys_ctnetlink", | |
54 | [NFNL_SUBSYS_CTNETLINK_EXP] = "nfnl_subsys_ctnetlink_exp", | |
55 | [NFNL_SUBSYS_QUEUE] = "nfnl_subsys_queue", | |
56 | [NFNL_SUBSYS_ULOG] = "nfnl_subsys_ulog", | |
57 | [NFNL_SUBSYS_OSF] = "nfnl_subsys_osf", | |
58 | [NFNL_SUBSYS_IPSET] = "nfnl_subsys_ipset", | |
59 | [NFNL_SUBSYS_ACCT] = "nfnl_subsys_acct", | |
60 | [NFNL_SUBSYS_CTNETLINK_TIMEOUT] = "nfnl_subsys_cttimeout", | |
61 | [NFNL_SUBSYS_CTHELPER] = "nfnl_subsys_cthelper", | |
62 | [NFNL_SUBSYS_NFTABLES] = "nfnl_subsys_nftables", | |
63 | [NFNL_SUBSYS_NFT_COMPAT] = "nfnl_subsys_nftcompat", | |
64 | }; | |
65 | ||
03292745 PNA |
66 | static const int nfnl_group2type[NFNLGRP_MAX+1] = { |
67 | [NFNLGRP_CONNTRACK_NEW] = NFNL_SUBSYS_CTNETLINK, | |
68 | [NFNLGRP_CONNTRACK_UPDATE] = NFNL_SUBSYS_CTNETLINK, | |
69 | [NFNLGRP_CONNTRACK_DESTROY] = NFNL_SUBSYS_CTNETLINK, | |
70 | [NFNLGRP_CONNTRACK_EXP_NEW] = NFNL_SUBSYS_CTNETLINK_EXP, | |
71 | [NFNLGRP_CONNTRACK_EXP_UPDATE] = NFNL_SUBSYS_CTNETLINK_EXP, | |
72 | [NFNLGRP_CONNTRACK_EXP_DESTROY] = NFNL_SUBSYS_CTNETLINK_EXP, | |
97840cb6 PNA |
73 | [NFNLGRP_NFTABLES] = NFNL_SUBSYS_NFTABLES, |
74 | [NFNLGRP_ACCT_QUOTA] = NFNL_SUBSYS_ACCT, | |
33d5a7b1 | 75 | [NFNLGRP_NFTRACE] = NFNL_SUBSYS_NFTABLES, |
03292745 PNA |
76 | }; |
77 | ||
c14b78e7 | 78 | void nfnl_lock(__u8 subsys_id) |
f9e815b3 | 79 | { |
c14b78e7 | 80 | mutex_lock(&table[subsys_id].mutex); |
f9e815b3 | 81 | } |
e6a7d3c0 | 82 | EXPORT_SYMBOL_GPL(nfnl_lock); |
f9e815b3 | 83 | |
c14b78e7 | 84 | void nfnl_unlock(__u8 subsys_id) |
a3c5029c | 85 | { |
c14b78e7 | 86 | mutex_unlock(&table[subsys_id].mutex); |
f9e815b3 | 87 | } |
e6a7d3c0 | 88 | EXPORT_SYMBOL_GPL(nfnl_unlock); |
f9e815b3 | 89 | |
0eb5db7a | 90 | #ifdef CONFIG_PROVE_LOCKING |
875e0829 | 91 | bool lockdep_nfnl_is_held(u8 subsys_id) |
0eb5db7a PM |
92 | { |
93 | return lockdep_is_held(&table[subsys_id].mutex); | |
94 | } | |
95 | EXPORT_SYMBOL_GPL(lockdep_nfnl_is_held); | |
96 | #endif | |
97 | ||
7c8d4cb4 | 98 | int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n) |
f9e815b3 | 99 | { |
7b7744e2 KC |
100 | u8 cb_id; |
101 | ||
102 | /* Sanity-check attr_count size to avoid stack buffer overflow. */ | |
103 | for (cb_id = 0; cb_id < n->cb_count; cb_id++) | |
104 | if (WARN_ON(n->cb[cb_id].attr_count > NFNL_MAX_ATTR_COUNT)) | |
105 | return -EINVAL; | |
106 | ||
c14b78e7 PNA |
107 | nfnl_lock(n->subsys_id); |
108 | if (table[n->subsys_id].subsys) { | |
109 | nfnl_unlock(n->subsys_id); | |
0ab43f84 HW |
110 | return -EBUSY; |
111 | } | |
c14b78e7 PNA |
112 | rcu_assign_pointer(table[n->subsys_id].subsys, n); |
113 | nfnl_unlock(n->subsys_id); | |
f9e815b3 HW |
114 | |
115 | return 0; | |
116 | } | |
f4bc177f | 117 | EXPORT_SYMBOL_GPL(nfnetlink_subsys_register); |
f9e815b3 | 118 | |
7c8d4cb4 | 119 | int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n) |
f9e815b3 | 120 | { |
c14b78e7 PNA |
121 | nfnl_lock(n->subsys_id); |
122 | table[n->subsys_id].subsys = NULL; | |
123 | nfnl_unlock(n->subsys_id); | |
6b75e3e8 | 124 | synchronize_rcu(); |
f9e815b3 HW |
125 | return 0; |
126 | } | |
f4bc177f | 127 | EXPORT_SYMBOL_GPL(nfnetlink_subsys_unregister); |
f9e815b3 | 128 | |
b745d035 | 129 | static inline const struct nfnetlink_subsystem *nfnetlink_get_subsys(u16 type) |
f9e815b3 | 130 | { |
b745d035 | 131 | u8 subsys_id = NFNL_SUBSYS_ID(type); |
f9e815b3 | 132 | |
ac0f1d98 | 133 | if (subsys_id >= NFNL_SUBSYS_COUNT) |
f9e815b3 HW |
134 | return NULL; |
135 | ||
c14b78e7 | 136 | return rcu_dereference(table[subsys_id].subsys); |
f9e815b3 HW |
137 | } |
138 | ||
7c8d4cb4 | 139 | static inline const struct nfnl_callback * |
b745d035 | 140 | nfnetlink_find_client(u16 type, const struct nfnetlink_subsystem *ss) |
f9e815b3 | 141 | { |
b745d035 | 142 | u8 cb_id = NFNL_MSG_TYPE(type); |
601e68e1 | 143 | |
67ca3966 | 144 | if (cb_id >= ss->cb_count) |
f9e815b3 | 145 | return NULL; |
f9e815b3 HW |
146 | |
147 | return &ss->cb[cb_id]; | |
148 | } | |
149 | ||
cd8c20b6 | 150 | int nfnetlink_has_listeners(struct net *net, unsigned int group) |
a2427692 | 151 | { |
cd8c20b6 | 152 | return netlink_has_listeners(net->nfnl, group); |
a2427692 PM |
153 | } |
154 | EXPORT_SYMBOL_GPL(nfnetlink_has_listeners); | |
155 | ||
ec464e5d | 156 | int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 portid, |
95c96174 | 157 | unsigned int group, int echo, gfp_t flags) |
f9e815b3 | 158 | { |
ec464e5d | 159 | return nlmsg_notify(net->nfnl, skb, portid, group, echo, flags); |
f9e815b3 | 160 | } |
f4bc177f | 161 | EXPORT_SYMBOL_GPL(nfnetlink_send); |
f9e815b3 | 162 | |
ec464e5d | 163 | int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error) |
dd5b6ce6 | 164 | { |
ec464e5d | 165 | return netlink_set_err(net->nfnl, portid, group, error); |
dd5b6ce6 PNA |
166 | } |
167 | EXPORT_SYMBOL_GPL(nfnetlink_set_err); | |
168 | ||
ee921183 | 169 | int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid) |
f9e815b3 | 170 | { |
ee921183 PNA |
171 | int err; |
172 | ||
173 | err = nlmsg_unicast(net->nfnl, skb, portid); | |
174 | if (err == -EAGAIN) | |
175 | err = -ENOBUFS; | |
176 | ||
177 | return err; | |
f9e815b3 | 178 | } |
f4bc177f | 179 | EXPORT_SYMBOL_GPL(nfnetlink_unicast); |
f9e815b3 HW |
180 | |
181 | /* Process one complete nfnetlink message. */ | |
2d4bc933 JB |
182 | static int nfnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, |
183 | struct netlink_ext_ack *extack) | |
f9e815b3 | 184 | { |
cd8c20b6 | 185 | struct net *net = sock_net(skb->sk); |
7c8d4cb4 PM |
186 | const struct nfnl_callback *nc; |
187 | const struct nfnetlink_subsystem *ss; | |
1d00a4eb | 188 | int type, err; |
f9e815b3 | 189 | |
f9e815b3 | 190 | /* All the messages must at least contain nfgenmsg */ |
573ce260 | 191 | if (nlmsg_len(nlh) < sizeof(struct nfgenmsg)) |
f9e815b3 | 192 | return 0; |
f9e815b3 HW |
193 | |
194 | type = nlh->nlmsg_type; | |
e6a7d3c0 | 195 | replay: |
6b75e3e8 | 196 | rcu_read_lock(); |
f9e815b3 | 197 | ss = nfnetlink_get_subsys(type); |
0ab43f84 | 198 | if (!ss) { |
95a5afca | 199 | #ifdef CONFIG_MODULES |
6b75e3e8 | 200 | rcu_read_unlock(); |
37d2e7a2 | 201 | request_module("nfnetlink-subsys-%d", NFNL_SUBSYS_ID(type)); |
6b75e3e8 | 202 | rcu_read_lock(); |
37d2e7a2 | 203 | ss = nfnetlink_get_subsys(type); |
0ab43f84 HW |
204 | if (!ss) |
205 | #endif | |
6b75e3e8 ED |
206 | { |
207 | rcu_read_unlock(); | |
1d00a4eb | 208 | return -EINVAL; |
6b75e3e8 | 209 | } |
0ab43f84 | 210 | } |
f9e815b3 HW |
211 | |
212 | nc = nfnetlink_find_client(type, ss); | |
6b75e3e8 ED |
213 | if (!nc) { |
214 | rcu_read_unlock(); | |
1d00a4eb | 215 | return -EINVAL; |
6b75e3e8 | 216 | } |
f9e815b3 | 217 | |
f9e815b3 | 218 | { |
573ce260 | 219 | int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); |
b745d035 | 220 | u8 cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type); |
7b7744e2 | 221 | struct nlattr *cda[NFNL_MAX_ATTR_COUNT + 1]; |
f49c857f PNA |
222 | struct nlattr *attr = (void *)nlh + min_len; |
223 | int attrlen = nlh->nlmsg_len - min_len; | |
c14b78e7 | 224 | __u8 subsys_id = NFNL_SUBSYS_ID(type); |
f49c857f | 225 | |
7b7744e2 KC |
226 | /* Sanity-check NFNL_MAX_ATTR_COUNT */ |
227 | if (ss->cb[cb_id].attr_count > NFNL_MAX_ATTR_COUNT) { | |
228 | rcu_read_unlock(); | |
229 | return -ENOMEM; | |
230 | } | |
231 | ||
8cb08174 JB |
232 | err = nla_parse_deprecated(cda, ss->cb[cb_id].attr_count, |
233 | attr, attrlen, | |
234 | ss->cb[cb_id].policy, extack); | |
4009e188 TB |
235 | if (err < 0) { |
236 | rcu_read_unlock(); | |
f49c857f | 237 | return err; |
4009e188 | 238 | } |
601e68e1 | 239 | |
6b75e3e8 | 240 | if (nc->call_rcu) { |
7b8002a1 | 241 | err = nc->call_rcu(net, net->nfnl, skb, nlh, |
04ba724b PNA |
242 | (const struct nlattr **)cda, |
243 | extack); | |
6b75e3e8 ED |
244 | rcu_read_unlock(); |
245 | } else { | |
246 | rcu_read_unlock(); | |
c14b78e7 | 247 | nfnl_lock(subsys_id); |
9c55d3b5 | 248 | if (nfnl_dereference_protected(subsys_id) != ss || |
6b75e3e8 ED |
249 | nfnetlink_find_client(type, ss) != nc) |
250 | err = -EAGAIN; | |
59560a38 | 251 | else if (nc->call) |
7b8002a1 | 252 | err = nc->call(net, net->nfnl, skb, nlh, |
04ba724b PNA |
253 | (const struct nlattr **)cda, |
254 | extack); | |
59560a38 TB |
255 | else |
256 | err = -EINVAL; | |
c14b78e7 | 257 | nfnl_unlock(subsys_id); |
6b75e3e8 | 258 | } |
e6a7d3c0 PNA |
259 | if (err == -EAGAIN) |
260 | goto replay; | |
261 | return err; | |
f9e815b3 | 262 | } |
f9e815b3 HW |
263 | } |
264 | ||
cbb8125e PNA |
265 | struct nfnl_err { |
266 | struct list_head head; | |
267 | struct nlmsghdr *nlh; | |
268 | int err; | |
04ba724b | 269 | struct netlink_ext_ack extack; |
cbb8125e PNA |
270 | }; |
271 | ||
04ba724b PNA |
272 | static int nfnl_err_add(struct list_head *list, struct nlmsghdr *nlh, int err, |
273 | const struct netlink_ext_ack *extack) | |
cbb8125e PNA |
274 | { |
275 | struct nfnl_err *nfnl_err; | |
276 | ||
277 | nfnl_err = kmalloc(sizeof(struct nfnl_err), GFP_KERNEL); | |
278 | if (nfnl_err == NULL) | |
279 | return -ENOMEM; | |
280 | ||
281 | nfnl_err->nlh = nlh; | |
282 | nfnl_err->err = err; | |
04ba724b | 283 | nfnl_err->extack = *extack; |
cbb8125e PNA |
284 | list_add_tail(&nfnl_err->head, list); |
285 | ||
286 | return 0; | |
287 | } | |
288 | ||
289 | static void nfnl_err_del(struct nfnl_err *nfnl_err) | |
290 | { | |
291 | list_del(&nfnl_err->head); | |
292 | kfree(nfnl_err); | |
293 | } | |
294 | ||
295 | static void nfnl_err_reset(struct list_head *err_list) | |
296 | { | |
297 | struct nfnl_err *nfnl_err, *next; | |
298 | ||
299 | list_for_each_entry_safe(nfnl_err, next, err_list, head) | |
300 | nfnl_err_del(nfnl_err); | |
301 | } | |
302 | ||
303 | static void nfnl_err_deliver(struct list_head *err_list, struct sk_buff *skb) | |
304 | { | |
305 | struct nfnl_err *nfnl_err, *next; | |
306 | ||
307 | list_for_each_entry_safe(nfnl_err, next, err_list, head) { | |
04ba724b PNA |
308 | netlink_ack(skb, nfnl_err->nlh, nfnl_err->err, |
309 | &nfnl_err->extack); | |
cbb8125e PNA |
310 | nfnl_err_del(nfnl_err); |
311 | } | |
312 | } | |
313 | ||
6742b9e3 PNA |
314 | enum { |
315 | NFNL_BATCH_FAILURE = (1 << 0), | |
316 | NFNL_BATCH_DONE = (1 << 1), | |
317 | NFNL_BATCH_REPLAY = (1 << 2), | |
318 | }; | |
319 | ||
0628b123 | 320 | static void nfnetlink_rcv_batch(struct sk_buff *skb, struct nlmsghdr *nlh, |
8c4d4e8b | 321 | u16 subsys_id, u32 genid) |
0628b123 | 322 | { |
0f816232 | 323 | struct sk_buff *oskb = skb; |
0628b123 PNA |
324 | struct net *net = sock_net(skb->sk); |
325 | const struct nfnetlink_subsystem *ss; | |
326 | const struct nfnl_callback *nc; | |
04ba724b | 327 | struct netlink_ext_ack extack; |
4eba8b78 | 328 | LIST_HEAD(err_list); |
6742b9e3 | 329 | u32 status; |
0628b123 PNA |
330 | int err; |
331 | ||
332 | if (subsys_id >= NFNL_SUBSYS_COUNT) | |
2d4bc933 | 333 | return netlink_ack(skb, nlh, -EINVAL, NULL); |
0628b123 | 334 | replay: |
6742b9e3 | 335 | status = 0; |
c0391b6a | 336 | replay_abort: |
0f816232 DJ |
337 | skb = netlink_skb_clone(oskb, GFP_KERNEL); |
338 | if (!skb) | |
2d4bc933 | 339 | return netlink_ack(oskb, nlh, -ENOMEM, NULL); |
0628b123 | 340 | |
0628b123 | 341 | nfnl_lock(subsys_id); |
9c55d3b5 | 342 | ss = nfnl_dereference_protected(subsys_id); |
0628b123 PNA |
343 | if (!ss) { |
344 | #ifdef CONFIG_MODULES | |
345 | nfnl_unlock(subsys_id); | |
346 | request_module("nfnetlink-subsys-%d", subsys_id); | |
347 | nfnl_lock(subsys_id); | |
9c55d3b5 | 348 | ss = nfnl_dereference_protected(subsys_id); |
0628b123 PNA |
349 | if (!ss) |
350 | #endif | |
351 | { | |
352 | nfnl_unlock(subsys_id); | |
2d4bc933 | 353 | netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL); |
0f816232 | 354 | return kfree_skb(skb); |
0628b123 PNA |
355 | } |
356 | } | |
357 | ||
ca2f18be | 358 | if (!ss->valid_genid || !ss->commit || !ss->abort) { |
0628b123 | 359 | nfnl_unlock(subsys_id); |
2d4bc933 | 360 | netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL); |
ecd15dd7 | 361 | return kfree_skb(skb); |
0628b123 PNA |
362 | } |
363 | ||
be2ab5b4 FW |
364 | if (!try_module_get(ss->owner)) { |
365 | nfnl_unlock(subsys_id); | |
366 | netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL); | |
367 | return kfree_skb(skb); | |
368 | } | |
369 | ||
ca2f18be | 370 | if (!ss->valid_genid(net, genid)) { |
be2ab5b4 | 371 | module_put(ss->owner); |
8c4d4e8b | 372 | nfnl_unlock(subsys_id); |
2d4bc933 | 373 | netlink_ack(oskb, nlh, -ERESTART, NULL); |
8c4d4e8b PNA |
374 | return kfree_skb(skb); |
375 | } | |
376 | ||
f102d66b FW |
377 | nfnl_unlock(subsys_id); |
378 | ||
0628b123 PNA |
379 | while (skb->len >= nlmsg_total_size(0)) { |
380 | int msglen, type; | |
381 | ||
8a3d4c36 FW |
382 | if (fatal_signal_pending(current)) { |
383 | nfnl_err_reset(&err_list); | |
384 | err = -EINTR; | |
385 | status = NFNL_BATCH_FAILURE; | |
386 | goto done; | |
387 | } | |
388 | ||
04ba724b | 389 | memset(&extack, 0, sizeof(extack)); |
0628b123 PNA |
390 | nlh = nlmsg_hdr(skb); |
391 | err = 0; | |
392 | ||
c58d6c93 PT |
393 | if (nlh->nlmsg_len < NLMSG_HDRLEN || |
394 | skb->len < nlh->nlmsg_len || | |
395 | nlmsg_len(nlh) < sizeof(struct nfgenmsg)) { | |
396 | nfnl_err_reset(&err_list); | |
397 | status |= NFNL_BATCH_FAILURE; | |
398 | goto done; | |
0628b123 PNA |
399 | } |
400 | ||
401 | /* Only requests are handled by the kernel */ | |
402 | if (!(nlh->nlmsg_flags & NLM_F_REQUEST)) { | |
403 | err = -EINVAL; | |
404 | goto ack; | |
405 | } | |
406 | ||
407 | type = nlh->nlmsg_type; | |
408 | if (type == NFNL_MSG_BATCH_BEGIN) { | |
409 | /* Malformed: Batch begin twice */ | |
cbb8125e | 410 | nfnl_err_reset(&err_list); |
6742b9e3 | 411 | status |= NFNL_BATCH_FAILURE; |
0628b123 PNA |
412 | goto done; |
413 | } else if (type == NFNL_MSG_BATCH_END) { | |
6742b9e3 | 414 | status |= NFNL_BATCH_DONE; |
0628b123 PNA |
415 | goto done; |
416 | } else if (type < NLMSG_MIN_TYPE) { | |
417 | err = -EINVAL; | |
418 | goto ack; | |
419 | } | |
420 | ||
421 | /* We only accept a batch with messages for the same | |
422 | * subsystem. | |
423 | */ | |
424 | if (NFNL_SUBSYS_ID(type) != subsys_id) { | |
425 | err = -EINVAL; | |
426 | goto ack; | |
427 | } | |
428 | ||
429 | nc = nfnetlink_find_client(type, ss); | |
430 | if (!nc) { | |
431 | err = -EINVAL; | |
432 | goto ack; | |
433 | } | |
434 | ||
435 | { | |
436 | int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); | |
b745d035 | 437 | u8 cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type); |
7b7744e2 | 438 | struct nlattr *cda[NFNL_MAX_ATTR_COUNT + 1]; |
0628b123 PNA |
439 | struct nlattr *attr = (void *)nlh + min_len; |
440 | int attrlen = nlh->nlmsg_len - min_len; | |
441 | ||
7b7744e2 KC |
442 | /* Sanity-check NFTA_MAX_ATTR */ |
443 | if (ss->cb[cb_id].attr_count > NFNL_MAX_ATTR_COUNT) { | |
444 | err = -ENOMEM; | |
445 | goto ack; | |
446 | } | |
447 | ||
8cb08174 JB |
448 | err = nla_parse_deprecated(cda, |
449 | ss->cb[cb_id].attr_count, | |
450 | attr, attrlen, | |
451 | ss->cb[cb_id].policy, NULL); | |
0628b123 PNA |
452 | if (err < 0) |
453 | goto ack; | |
454 | ||
455 | if (nc->call_batch) { | |
633c9a84 | 456 | err = nc->call_batch(net, net->nfnl, skb, nlh, |
04ba724b PNA |
457 | (const struct nlattr **)cda, |
458 | &extack); | |
0628b123 PNA |
459 | } |
460 | ||
461 | /* The lock was released to autoload some module, we | |
462 | * have to abort and start from scratch using the | |
463 | * original skb. | |
464 | */ | |
465 | if (err == -EAGAIN) { | |
6742b9e3 | 466 | status |= NFNL_BATCH_REPLAY; |
71ad00c5 | 467 | goto done; |
0628b123 PNA |
468 | } |
469 | } | |
470 | ack: | |
471 | if (nlh->nlmsg_flags & NLM_F_ACK || err) { | |
cbb8125e PNA |
472 | /* Errors are delivered once the full batch has been |
473 | * processed, this avoids that the same error is | |
474 | * reported several times when replaying the batch. | |
475 | */ | |
04ba724b | 476 | if (nfnl_err_add(&err_list, nlh, err, &extack) < 0) { |
cbb8125e PNA |
477 | /* We failed to enqueue an error, reset the |
478 | * list of errors and send OOM to userspace | |
479 | * pointing to the batch header. | |
480 | */ | |
481 | nfnl_err_reset(&err_list); | |
2d4bc933 JB |
482 | netlink_ack(oskb, nlmsg_hdr(oskb), -ENOMEM, |
483 | NULL); | |
6742b9e3 | 484 | status |= NFNL_BATCH_FAILURE; |
cbb8125e PNA |
485 | goto done; |
486 | } | |
0628b123 PNA |
487 | /* We don't stop processing the batch on errors, thus, |
488 | * userspace gets all the errors that the batch | |
489 | * triggers. | |
490 | */ | |
0628b123 | 491 | if (err) |
6742b9e3 | 492 | status |= NFNL_BATCH_FAILURE; |
0628b123 | 493 | } |
71ad00c5 | 494 | |
0628b123 PNA |
495 | msglen = NLMSG_ALIGN(nlh->nlmsg_len); |
496 | if (msglen > skb->len) | |
497 | msglen = skb->len; | |
498 | skb_pull(skb, msglen); | |
499 | } | |
500 | done: | |
6742b9e3 | 501 | if (status & NFNL_BATCH_REPLAY) { |
c0391b6a | 502 | ss->abort(net, oskb, NFNL_ABORT_AUTOLOAD); |
6742b9e3 | 503 | nfnl_err_reset(&err_list); |
6742b9e3 | 504 | kfree_skb(skb); |
be2ab5b4 | 505 | module_put(ss->owner); |
6742b9e3 PNA |
506 | goto replay; |
507 | } else if (status == NFNL_BATCH_DONE) { | |
00308791 FW |
508 | err = ss->commit(net, oskb); |
509 | if (err == -EAGAIN) { | |
510 | status |= NFNL_BATCH_REPLAY; | |
511 | goto done; | |
512 | } else if (err) { | |
c0391b6a | 513 | ss->abort(net, oskb, NFNL_ABORT_NONE); |
00308791 FW |
514 | netlink_ack(oskb, nlmsg_hdr(oskb), err, NULL); |
515 | } | |
6742b9e3 | 516 | } else { |
c0391b6a PNA |
517 | enum nfnl_abort_action abort_action; |
518 | ||
519 | if (status & NFNL_BATCH_FAILURE) | |
520 | abort_action = NFNL_ABORT_NONE; | |
521 | else | |
522 | abort_action = NFNL_ABORT_VALIDATE; | |
523 | ||
524 | err = ss->abort(net, oskb, abort_action); | |
525 | if (err == -EAGAIN) { | |
526 | nfnl_err_reset(&err_list); | |
527 | kfree_skb(skb); | |
528 | module_put(ss->owner); | |
529 | status |= NFNL_BATCH_FAILURE; | |
530 | goto replay_abort; | |
531 | } | |
6742b9e3 | 532 | } |
a654de8f PNA |
533 | if (ss->cleanup) |
534 | ss->cleanup(net); | |
0628b123 | 535 | |
cbb8125e | 536 | nfnl_err_deliver(&err_list, oskb); |
0f816232 | 537 | kfree_skb(skb); |
be2ab5b4 | 538 | module_put(ss->owner); |
0628b123 PNA |
539 | } |
540 | ||
8c4d4e8b PNA |
541 | static const struct nla_policy nfnl_batch_policy[NFNL_BATCH_MAX + 1] = { |
542 | [NFNL_BATCH_GENID] = { .type = NLA_U32 }, | |
543 | }; | |
544 | ||
48656835 | 545 | static void nfnetlink_rcv_skb_batch(struct sk_buff *skb, struct nlmsghdr *nlh) |
f9e815b3 | 546 | { |
8c4d4e8b PNA |
547 | int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); |
548 | struct nlattr *attr = (void *)nlh + min_len; | |
549 | struct nlattr *cda[NFNL_BATCH_MAX + 1]; | |
550 | int attrlen = nlh->nlmsg_len - min_len; | |
48656835 | 551 | struct nfgenmsg *nfgenmsg; |
8c4d4e8b PNA |
552 | int msglen, err; |
553 | u32 gen_id = 0; | |
b745d035 | 554 | u16 res_id; |
0628b123 | 555 | |
48656835 PNA |
556 | msglen = NLMSG_ALIGN(nlh->nlmsg_len); |
557 | if (msglen > skb->len) | |
558 | msglen = skb->len; | |
559 | ||
f55ce7b0 | 560 | if (skb->len < NLMSG_HDRLEN + sizeof(struct nfgenmsg)) |
48656835 PNA |
561 | return; |
562 | ||
8cb08174 JB |
563 | err = nla_parse_deprecated(cda, NFNL_BATCH_MAX, attr, attrlen, |
564 | nfnl_batch_policy, NULL); | |
8c4d4e8b | 565 | if (err < 0) { |
2d4bc933 | 566 | netlink_ack(skb, nlh, err, NULL); |
8c4d4e8b PNA |
567 | return; |
568 | } | |
569 | if (cda[NFNL_BATCH_GENID]) | |
570 | gen_id = ntohl(nla_get_be32(cda[NFNL_BATCH_GENID])); | |
571 | ||
48656835 PNA |
572 | nfgenmsg = nlmsg_data(nlh); |
573 | skb_pull(skb, msglen); | |
574 | /* Work around old nft using host byte order */ | |
575 | if (nfgenmsg->res_id == NFNL_SUBSYS_NFTABLES) | |
576 | res_id = NFNL_SUBSYS_NFTABLES; | |
577 | else | |
578 | res_id = ntohs(nfgenmsg->res_id); | |
579 | ||
8c4d4e8b | 580 | nfnetlink_rcv_batch(skb, nlh, res_id, gen_id); |
48656835 PNA |
581 | } |
582 | ||
583 | static void nfnetlink_rcv(struct sk_buff *skb) | |
584 | { | |
585 | struct nlmsghdr *nlh = nlmsg_hdr(skb); | |
586 | ||
f55ce7b0 MJ |
587 | if (skb->len < NLMSG_HDRLEN || |
588 | nlh->nlmsg_len < NLMSG_HDRLEN || | |
0628b123 PNA |
589 | skb->len < nlh->nlmsg_len) |
590 | return; | |
591 | ||
90f62cf3 | 592 | if (!netlink_net_capable(skb, CAP_NET_ADMIN)) { |
2d4bc933 | 593 | netlink_ack(skb, nlh, -EPERM, NULL); |
cdbe7c2d JB |
594 | return; |
595 | } | |
596 | ||
48656835 PNA |
597 | if (nlh->nlmsg_type == NFNL_MSG_BATCH_BEGIN) |
598 | nfnetlink_rcv_skb_batch(skb, nlh); | |
599 | else | |
d4ef3835 | 600 | netlink_rcv_skb(skb, nfnetlink_rcv_msg); |
f9e815b3 HW |
601 | } |
602 | ||
03292745 | 603 | #ifdef CONFIG_MODULES |
023e2cfa | 604 | static int nfnetlink_bind(struct net *net, int group) |
03292745 PNA |
605 | { |
606 | const struct nfnetlink_subsystem *ss; | |
97840cb6 PNA |
607 | int type; |
608 | ||
609 | if (group <= NFNLGRP_NONE || group > NFNLGRP_MAX) | |
62924af2 | 610 | return 0; |
97840cb6 PNA |
611 | |
612 | type = nfnl_group2type[group]; | |
03292745 PNA |
613 | |
614 | rcu_read_lock(); | |
dbc3617f | 615 | ss = nfnetlink_get_subsys(type << 8); |
03292745 | 616 | rcu_read_unlock(); |
bfe4bc71 | 617 | if (!ss) |
1b0890cd | 618 | request_module_nowait("nfnetlink-subsys-%d", type); |
4f520900 | 619 | return 0; |
03292745 PNA |
620 | } |
621 | #endif | |
622 | ||
cd8c20b6 | 623 | static int __net_init nfnetlink_net_init(struct net *net) |
f9e815b3 | 624 | { |
cd8c20b6 | 625 | struct sock *nfnl; |
a31f2d17 PNA |
626 | struct netlink_kernel_cfg cfg = { |
627 | .groups = NFNLGRP_MAX, | |
628 | .input = nfnetlink_rcv, | |
03292745 PNA |
629 | #ifdef CONFIG_MODULES |
630 | .bind = nfnetlink_bind, | |
631 | #endif | |
a31f2d17 | 632 | }; |
cd8c20b6 | 633 | |
9f00d977 | 634 | nfnl = netlink_kernel_create(net, NETLINK_NETFILTER, &cfg); |
cd8c20b6 AD |
635 | if (!nfnl) |
636 | return -ENOMEM; | |
637 | net->nfnl_stash = nfnl; | |
cf778b00 | 638 | rcu_assign_pointer(net->nfnl, nfnl); |
cd8c20b6 | 639 | return 0; |
f9e815b3 HW |
640 | } |
641 | ||
cd8c20b6 | 642 | static void __net_exit nfnetlink_net_exit_batch(struct list_head *net_exit_list) |
f9e815b3 | 643 | { |
cd8c20b6 | 644 | struct net *net; |
f9e815b3 | 645 | |
cd8c20b6 | 646 | list_for_each_entry(net, net_exit_list, exit_list) |
a9b3cd7f | 647 | RCU_INIT_POINTER(net->nfnl, NULL); |
cd8c20b6 AD |
648 | synchronize_net(); |
649 | list_for_each_entry(net, net_exit_list, exit_list) | |
650 | netlink_kernel_release(net->nfnl_stash); | |
651 | } | |
f9e815b3 | 652 | |
cd8c20b6 AD |
653 | static struct pernet_operations nfnetlink_net_ops = { |
654 | .init = nfnetlink_net_init, | |
655 | .exit_batch = nfnetlink_net_exit_batch, | |
656 | }; | |
657 | ||
658 | static int __init nfnetlink_init(void) | |
659 | { | |
c14b78e7 PNA |
660 | int i; |
661 | ||
97840cb6 PNA |
662 | for (i = NFNLGRP_NONE + 1; i <= NFNLGRP_MAX; i++) |
663 | BUG_ON(nfnl_group2type[i] == NFNL_SUBSYS_NONE); | |
664 | ||
c14b78e7 | 665 | for (i=0; i<NFNL_SUBSYS_COUNT; i++) |
ab6c41ee | 666 | __mutex_init(&table[i].mutex, nfnl_lockdep_names[i], &nfnl_lockdep_keys[i]); |
c14b78e7 | 667 | |
cd8c20b6 | 668 | return register_pernet_subsys(&nfnetlink_net_ops); |
f9e815b3 HW |
669 | } |
670 | ||
cd8c20b6 AD |
671 | static void __exit nfnetlink_exit(void) |
672 | { | |
cd8c20b6 AD |
673 | unregister_pernet_subsys(&nfnetlink_net_ops); |
674 | } | |
f9e815b3 HW |
675 | module_init(nfnetlink_init); |
676 | module_exit(nfnetlink_exit); |