Commit | Line | Data |
---|---|---|
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> |
1be05ea7 | 31 | #include <net/netns/generic.h> |
fdf64911 | 32 | #include <linux/netfilter.h> |
f9e815b3 HW |
33 | #include <linux/netfilter/nfnetlink.h> |
34 | ||
35 | MODULE_LICENSE("GPL"); | |
4fdb3bb7 HW |
36 | MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>"); |
37 | MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_NETFILTER); | |
4cacc395 | 38 | MODULE_DESCRIPTION("Netfilter messages via netlink socket"); |
f9e815b3 | 39 | |
9c55d3b5 FW |
40 | #define nfnl_dereference_protected(id) \ |
41 | rcu_dereference_protected(table[(id)].subsys, \ | |
42 | lockdep_nfnl_is_held((id))) | |
43 | ||
7b7744e2 KC |
44 | #define NFNL_MAX_ATTR_COUNT 32 |
45 | ||
1be05ea7 FW |
46 | static unsigned int nfnetlink_pernet_id __read_mostly; |
47 | ||
0b2f3212 FW |
48 | #ifdef CONFIG_NF_CONNTRACK_EVENTS |
49 | static DEFINE_SPINLOCK(nfnl_grp_active_lock); | |
50 | #endif | |
51 | ||
1be05ea7 FW |
52 | struct nfnl_net { |
53 | struct sock *nfnl; | |
54 | }; | |
55 | ||
c14b78e7 PNA |
56 | static struct { |
57 | struct mutex mutex; | |
58 | const struct nfnetlink_subsystem __rcu *subsys; | |
59 | } table[NFNL_SUBSYS_COUNT]; | |
f9e815b3 | 60 | |
ab6c41ee FW |
61 | static struct lock_class_key nfnl_lockdep_keys[NFNL_SUBSYS_COUNT]; |
62 | ||
63 | static const char *const nfnl_lockdep_names[NFNL_SUBSYS_COUNT] = { | |
64 | [NFNL_SUBSYS_NONE] = "nfnl_subsys_none", | |
65 | [NFNL_SUBSYS_CTNETLINK] = "nfnl_subsys_ctnetlink", | |
66 | [NFNL_SUBSYS_CTNETLINK_EXP] = "nfnl_subsys_ctnetlink_exp", | |
67 | [NFNL_SUBSYS_QUEUE] = "nfnl_subsys_queue", | |
68 | [NFNL_SUBSYS_ULOG] = "nfnl_subsys_ulog", | |
69 | [NFNL_SUBSYS_OSF] = "nfnl_subsys_osf", | |
70 | [NFNL_SUBSYS_IPSET] = "nfnl_subsys_ipset", | |
71 | [NFNL_SUBSYS_ACCT] = "nfnl_subsys_acct", | |
72 | [NFNL_SUBSYS_CTNETLINK_TIMEOUT] = "nfnl_subsys_cttimeout", | |
73 | [NFNL_SUBSYS_CTHELPER] = "nfnl_subsys_cthelper", | |
74 | [NFNL_SUBSYS_NFTABLES] = "nfnl_subsys_nftables", | |
75 | [NFNL_SUBSYS_NFT_COMPAT] = "nfnl_subsys_nftcompat", | |
e2cf17d3 | 76 | [NFNL_SUBSYS_HOOK] = "nfnl_subsys_hook", |
ab6c41ee FW |
77 | }; |
78 | ||
03292745 PNA |
79 | static const int nfnl_group2type[NFNLGRP_MAX+1] = { |
80 | [NFNLGRP_CONNTRACK_NEW] = NFNL_SUBSYS_CTNETLINK, | |
81 | [NFNLGRP_CONNTRACK_UPDATE] = NFNL_SUBSYS_CTNETLINK, | |
82 | [NFNLGRP_CONNTRACK_DESTROY] = NFNL_SUBSYS_CTNETLINK, | |
83 | [NFNLGRP_CONNTRACK_EXP_NEW] = NFNL_SUBSYS_CTNETLINK_EXP, | |
84 | [NFNLGRP_CONNTRACK_EXP_UPDATE] = NFNL_SUBSYS_CTNETLINK_EXP, | |
85 | [NFNLGRP_CONNTRACK_EXP_DESTROY] = NFNL_SUBSYS_CTNETLINK_EXP, | |
97840cb6 PNA |
86 | [NFNLGRP_NFTABLES] = NFNL_SUBSYS_NFTABLES, |
87 | [NFNLGRP_ACCT_QUOTA] = NFNL_SUBSYS_ACCT, | |
33d5a7b1 | 88 | [NFNLGRP_NFTRACE] = NFNL_SUBSYS_NFTABLES, |
03292745 PNA |
89 | }; |
90 | ||
1be05ea7 FW |
91 | static struct nfnl_net *nfnl_pernet(struct net *net) |
92 | { | |
93 | return net_generic(net, nfnetlink_pernet_id); | |
94 | } | |
95 | ||
c14b78e7 | 96 | void nfnl_lock(__u8 subsys_id) |
f9e815b3 | 97 | { |
c14b78e7 | 98 | mutex_lock(&table[subsys_id].mutex); |
f9e815b3 | 99 | } |
e6a7d3c0 | 100 | EXPORT_SYMBOL_GPL(nfnl_lock); |
f9e815b3 | 101 | |
c14b78e7 | 102 | void nfnl_unlock(__u8 subsys_id) |
a3c5029c | 103 | { |
c14b78e7 | 104 | mutex_unlock(&table[subsys_id].mutex); |
f9e815b3 | 105 | } |
e6a7d3c0 | 106 | EXPORT_SYMBOL_GPL(nfnl_unlock); |
f9e815b3 | 107 | |
0eb5db7a | 108 | #ifdef CONFIG_PROVE_LOCKING |
875e0829 | 109 | bool lockdep_nfnl_is_held(u8 subsys_id) |
0eb5db7a PM |
110 | { |
111 | return lockdep_is_held(&table[subsys_id].mutex); | |
112 | } | |
113 | EXPORT_SYMBOL_GPL(lockdep_nfnl_is_held); | |
114 | #endif | |
115 | ||
7c8d4cb4 | 116 | int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n) |
f9e815b3 | 117 | { |
7b7744e2 KC |
118 | u8 cb_id; |
119 | ||
120 | /* Sanity-check attr_count size to avoid stack buffer overflow. */ | |
121 | for (cb_id = 0; cb_id < n->cb_count; cb_id++) | |
122 | if (WARN_ON(n->cb[cb_id].attr_count > NFNL_MAX_ATTR_COUNT)) | |
123 | return -EINVAL; | |
124 | ||
c14b78e7 PNA |
125 | nfnl_lock(n->subsys_id); |
126 | if (table[n->subsys_id].subsys) { | |
127 | nfnl_unlock(n->subsys_id); | |
0ab43f84 HW |
128 | return -EBUSY; |
129 | } | |
c14b78e7 PNA |
130 | rcu_assign_pointer(table[n->subsys_id].subsys, n); |
131 | nfnl_unlock(n->subsys_id); | |
f9e815b3 HW |
132 | |
133 | return 0; | |
134 | } | |
f4bc177f | 135 | EXPORT_SYMBOL_GPL(nfnetlink_subsys_register); |
f9e815b3 | 136 | |
7c8d4cb4 | 137 | int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n) |
f9e815b3 | 138 | { |
c14b78e7 PNA |
139 | nfnl_lock(n->subsys_id); |
140 | table[n->subsys_id].subsys = NULL; | |
141 | nfnl_unlock(n->subsys_id); | |
6b75e3e8 | 142 | synchronize_rcu(); |
f9e815b3 HW |
143 | return 0; |
144 | } | |
f4bc177f | 145 | EXPORT_SYMBOL_GPL(nfnetlink_subsys_unregister); |
f9e815b3 | 146 | |
b745d035 | 147 | static inline const struct nfnetlink_subsystem *nfnetlink_get_subsys(u16 type) |
f9e815b3 | 148 | { |
b745d035 | 149 | u8 subsys_id = NFNL_SUBSYS_ID(type); |
f9e815b3 | 150 | |
ac0f1d98 | 151 | if (subsys_id >= NFNL_SUBSYS_COUNT) |
f9e815b3 HW |
152 | return NULL; |
153 | ||
c14b78e7 | 154 | return rcu_dereference(table[subsys_id].subsys); |
f9e815b3 HW |
155 | } |
156 | ||
7c8d4cb4 | 157 | static inline const struct nfnl_callback * |
b745d035 | 158 | nfnetlink_find_client(u16 type, const struct nfnetlink_subsystem *ss) |
f9e815b3 | 159 | { |
b745d035 | 160 | u8 cb_id = NFNL_MSG_TYPE(type); |
601e68e1 | 161 | |
67ca3966 | 162 | if (cb_id >= ss->cb_count) |
f9e815b3 | 163 | return NULL; |
f9e815b3 HW |
164 | |
165 | return &ss->cb[cb_id]; | |
166 | } | |
167 | ||
cd8c20b6 | 168 | int nfnetlink_has_listeners(struct net *net, unsigned int group) |
a2427692 | 169 | { |
1be05ea7 FW |
170 | struct nfnl_net *nfnlnet = nfnl_pernet(net); |
171 | ||
172 | return netlink_has_listeners(nfnlnet->nfnl, group); | |
a2427692 PM |
173 | } |
174 | EXPORT_SYMBOL_GPL(nfnetlink_has_listeners); | |
175 | ||
ec464e5d | 176 | int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 portid, |
95c96174 | 177 | unsigned int group, int echo, gfp_t flags) |
f9e815b3 | 178 | { |
1be05ea7 FW |
179 | struct nfnl_net *nfnlnet = nfnl_pernet(net); |
180 | ||
181 | return nlmsg_notify(nfnlnet->nfnl, skb, portid, group, echo, flags); | |
f9e815b3 | 182 | } |
f4bc177f | 183 | EXPORT_SYMBOL_GPL(nfnetlink_send); |
f9e815b3 | 184 | |
ec464e5d | 185 | int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error) |
dd5b6ce6 | 186 | { |
1be05ea7 FW |
187 | struct nfnl_net *nfnlnet = nfnl_pernet(net); |
188 | ||
189 | return netlink_set_err(nfnlnet->nfnl, portid, group, error); | |
dd5b6ce6 PNA |
190 | } |
191 | EXPORT_SYMBOL_GPL(nfnetlink_set_err); | |
192 | ||
ee921183 | 193 | int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid) |
f9e815b3 | 194 | { |
1be05ea7 | 195 | struct nfnl_net *nfnlnet = nfnl_pernet(net); |
ee921183 PNA |
196 | int err; |
197 | ||
1be05ea7 | 198 | err = nlmsg_unicast(nfnlnet->nfnl, skb, portid); |
ee921183 PNA |
199 | if (err == -EAGAIN) |
200 | err = -ENOBUFS; | |
201 | ||
202 | return err; | |
f9e815b3 | 203 | } |
f4bc177f | 204 | EXPORT_SYMBOL_GPL(nfnetlink_unicast); |
f9e815b3 | 205 | |
237c609f FW |
206 | void nfnetlink_broadcast(struct net *net, struct sk_buff *skb, __u32 portid, |
207 | __u32 group, gfp_t allocation) | |
208 | { | |
1be05ea7 FW |
209 | struct nfnl_net *nfnlnet = nfnl_pernet(net); |
210 | ||
211 | netlink_broadcast(nfnlnet->nfnl, skb, portid, group, allocation); | |
237c609f FW |
212 | } |
213 | EXPORT_SYMBOL_GPL(nfnetlink_broadcast); | |
214 | ||
f9e815b3 | 215 | /* Process one complete nfnetlink message. */ |
2d4bc933 JB |
216 | static int nfnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, |
217 | struct netlink_ext_ack *extack) | |
f9e815b3 | 218 | { |
cd8c20b6 | 219 | struct net *net = sock_net(skb->sk); |
7c8d4cb4 PM |
220 | const struct nfnl_callback *nc; |
221 | const struct nfnetlink_subsystem *ss; | |
1d00a4eb | 222 | int type, err; |
f9e815b3 | 223 | |
f9e815b3 | 224 | /* All the messages must at least contain nfgenmsg */ |
573ce260 | 225 | if (nlmsg_len(nlh) < sizeof(struct nfgenmsg)) |
f9e815b3 | 226 | return 0; |
f9e815b3 HW |
227 | |
228 | type = nlh->nlmsg_type; | |
e6a7d3c0 | 229 | replay: |
6b75e3e8 | 230 | rcu_read_lock(); |
1be05ea7 | 231 | |
f9e815b3 | 232 | ss = nfnetlink_get_subsys(type); |
0ab43f84 | 233 | if (!ss) { |
95a5afca | 234 | #ifdef CONFIG_MODULES |
6b75e3e8 | 235 | rcu_read_unlock(); |
37d2e7a2 | 236 | request_module("nfnetlink-subsys-%d", NFNL_SUBSYS_ID(type)); |
6b75e3e8 | 237 | rcu_read_lock(); |
37d2e7a2 | 238 | ss = nfnetlink_get_subsys(type); |
0ab43f84 HW |
239 | if (!ss) |
240 | #endif | |
6b75e3e8 ED |
241 | { |
242 | rcu_read_unlock(); | |
1d00a4eb | 243 | return -EINVAL; |
6b75e3e8 | 244 | } |
0ab43f84 | 245 | } |
f9e815b3 HW |
246 | |
247 | nc = nfnetlink_find_client(type, ss); | |
6b75e3e8 ED |
248 | if (!nc) { |
249 | rcu_read_unlock(); | |
1d00a4eb | 250 | return -EINVAL; |
6b75e3e8 | 251 | } |
f9e815b3 | 252 | |
f9e815b3 | 253 | { |
573ce260 | 254 | int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); |
1be05ea7 | 255 | struct nfnl_net *nfnlnet = nfnl_pernet(net); |
b745d035 | 256 | u8 cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type); |
7b7744e2 | 257 | struct nlattr *cda[NFNL_MAX_ATTR_COUNT + 1]; |
f49c857f PNA |
258 | struct nlattr *attr = (void *)nlh + min_len; |
259 | int attrlen = nlh->nlmsg_len - min_len; | |
c14b78e7 | 260 | __u8 subsys_id = NFNL_SUBSYS_ID(type); |
a6555365 PNA |
261 | struct nfnl_info info = { |
262 | .net = net, | |
263 | .sk = nfnlnet->nfnl, | |
264 | .nlh = nlh, | |
ef4b65e5 | 265 | .nfmsg = nlmsg_data(nlh), |
a6555365 PNA |
266 | .extack = extack, |
267 | }; | |
f49c857f | 268 | |
7b7744e2 KC |
269 | /* Sanity-check NFNL_MAX_ATTR_COUNT */ |
270 | if (ss->cb[cb_id].attr_count > NFNL_MAX_ATTR_COUNT) { | |
271 | rcu_read_unlock(); | |
272 | return -ENOMEM; | |
273 | } | |
274 | ||
8cb08174 JB |
275 | err = nla_parse_deprecated(cda, ss->cb[cb_id].attr_count, |
276 | attr, attrlen, | |
277 | ss->cb[cb_id].policy, extack); | |
4009e188 TB |
278 | if (err < 0) { |
279 | rcu_read_unlock(); | |
f49c857f | 280 | return err; |
4009e188 | 281 | } |
601e68e1 | 282 | |
50f2db9e | 283 | if (!nc->call) { |
6b75e3e8 | 284 | rcu_read_unlock(); |
50f2db9e PNA |
285 | return -EINVAL; |
286 | } | |
287 | ||
288 | switch (nc->type) { | |
289 | case NFNL_CB_RCU: | |
290 | err = nc->call(skb, &info, (const struct nlattr **)cda); | |
291 | rcu_read_unlock(); | |
292 | break; | |
293 | case NFNL_CB_MUTEX: | |
6b75e3e8 | 294 | rcu_read_unlock(); |
c14b78e7 | 295 | nfnl_lock(subsys_id); |
9c55d3b5 | 296 | if (nfnl_dereference_protected(subsys_id) != ss || |
a6555365 | 297 | nfnetlink_find_client(type, ss) != nc) { |
03832a32 | 298 | nfnl_unlock(subsys_id); |
6b75e3e8 | 299 | err = -EAGAIN; |
50f2db9e | 300 | break; |
a6555365 | 301 | } |
50f2db9e | 302 | err = nc->call(skb, &info, (const struct nlattr **)cda); |
c14b78e7 | 303 | nfnl_unlock(subsys_id); |
50f2db9e PNA |
304 | break; |
305 | default: | |
7072a355 | 306 | rcu_read_unlock(); |
50f2db9e PNA |
307 | err = -EINVAL; |
308 | break; | |
6b75e3e8 | 309 | } |
e6a7d3c0 PNA |
310 | if (err == -EAGAIN) |
311 | goto replay; | |
312 | return err; | |
f9e815b3 | 313 | } |
f9e815b3 HW |
314 | } |
315 | ||
cbb8125e PNA |
316 | struct nfnl_err { |
317 | struct list_head head; | |
318 | struct nlmsghdr *nlh; | |
319 | int err; | |
04ba724b | 320 | struct netlink_ext_ack extack; |
cbb8125e PNA |
321 | }; |
322 | ||
04ba724b PNA |
323 | static int nfnl_err_add(struct list_head *list, struct nlmsghdr *nlh, int err, |
324 | const struct netlink_ext_ack *extack) | |
cbb8125e PNA |
325 | { |
326 | struct nfnl_err *nfnl_err; | |
327 | ||
328 | nfnl_err = kmalloc(sizeof(struct nfnl_err), GFP_KERNEL); | |
329 | if (nfnl_err == NULL) | |
330 | return -ENOMEM; | |
331 | ||
332 | nfnl_err->nlh = nlh; | |
333 | nfnl_err->err = err; | |
04ba724b | 334 | nfnl_err->extack = *extack; |
cbb8125e PNA |
335 | list_add_tail(&nfnl_err->head, list); |
336 | ||
337 | return 0; | |
338 | } | |
339 | ||
340 | static void nfnl_err_del(struct nfnl_err *nfnl_err) | |
341 | { | |
342 | list_del(&nfnl_err->head); | |
343 | kfree(nfnl_err); | |
344 | } | |
345 | ||
346 | static void nfnl_err_reset(struct list_head *err_list) | |
347 | { | |
348 | struct nfnl_err *nfnl_err, *next; | |
349 | ||
350 | list_for_each_entry_safe(nfnl_err, next, err_list, head) | |
351 | nfnl_err_del(nfnl_err); | |
352 | } | |
353 | ||
354 | static void nfnl_err_deliver(struct list_head *err_list, struct sk_buff *skb) | |
355 | { | |
356 | struct nfnl_err *nfnl_err, *next; | |
357 | ||
358 | list_for_each_entry_safe(nfnl_err, next, err_list, head) { | |
04ba724b PNA |
359 | netlink_ack(skb, nfnl_err->nlh, nfnl_err->err, |
360 | &nfnl_err->extack); | |
cbb8125e PNA |
361 | nfnl_err_del(nfnl_err); |
362 | } | |
363 | } | |
364 | ||
6742b9e3 PNA |
365 | enum { |
366 | NFNL_BATCH_FAILURE = (1 << 0), | |
367 | NFNL_BATCH_DONE = (1 << 1), | |
368 | NFNL_BATCH_REPLAY = (1 << 2), | |
369 | }; | |
370 | ||
0628b123 | 371 | static void nfnetlink_rcv_batch(struct sk_buff *skb, struct nlmsghdr *nlh, |
8c4d4e8b | 372 | u16 subsys_id, u32 genid) |
0628b123 | 373 | { |
0f816232 | 374 | struct sk_buff *oskb = skb; |
0628b123 PNA |
375 | struct net *net = sock_net(skb->sk); |
376 | const struct nfnetlink_subsystem *ss; | |
377 | const struct nfnl_callback *nc; | |
04ba724b | 378 | struct netlink_ext_ack extack; |
4eba8b78 | 379 | LIST_HEAD(err_list); |
6742b9e3 | 380 | u32 status; |
0628b123 PNA |
381 | int err; |
382 | ||
383 | if (subsys_id >= NFNL_SUBSYS_COUNT) | |
2d4bc933 | 384 | return netlink_ack(skb, nlh, -EINVAL, NULL); |
0628b123 | 385 | replay: |
6742b9e3 | 386 | status = 0; |
c0391b6a | 387 | replay_abort: |
0f816232 DJ |
388 | skb = netlink_skb_clone(oskb, GFP_KERNEL); |
389 | if (!skb) | |
2d4bc933 | 390 | return netlink_ack(oskb, nlh, -ENOMEM, NULL); |
0628b123 | 391 | |
0628b123 | 392 | nfnl_lock(subsys_id); |
9c55d3b5 | 393 | ss = nfnl_dereference_protected(subsys_id); |
0628b123 PNA |
394 | if (!ss) { |
395 | #ifdef CONFIG_MODULES | |
396 | nfnl_unlock(subsys_id); | |
397 | request_module("nfnetlink-subsys-%d", subsys_id); | |
398 | nfnl_lock(subsys_id); | |
9c55d3b5 | 399 | ss = nfnl_dereference_protected(subsys_id); |
0628b123 PNA |
400 | if (!ss) |
401 | #endif | |
402 | { | |
403 | nfnl_unlock(subsys_id); | |
2d4bc933 | 404 | netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL); |
0f816232 | 405 | return kfree_skb(skb); |
0628b123 PNA |
406 | } |
407 | } | |
408 | ||
ca2f18be | 409 | if (!ss->valid_genid || !ss->commit || !ss->abort) { |
0628b123 | 410 | nfnl_unlock(subsys_id); |
2d4bc933 | 411 | netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL); |
ecd15dd7 | 412 | return kfree_skb(skb); |
0628b123 PNA |
413 | } |
414 | ||
be2ab5b4 FW |
415 | if (!try_module_get(ss->owner)) { |
416 | nfnl_unlock(subsys_id); | |
417 | netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL); | |
418 | return kfree_skb(skb); | |
419 | } | |
420 | ||
ca2f18be | 421 | if (!ss->valid_genid(net, genid)) { |
be2ab5b4 | 422 | module_put(ss->owner); |
8c4d4e8b | 423 | nfnl_unlock(subsys_id); |
2d4bc933 | 424 | netlink_ack(oskb, nlh, -ERESTART, NULL); |
8c4d4e8b PNA |
425 | return kfree_skb(skb); |
426 | } | |
427 | ||
f102d66b FW |
428 | nfnl_unlock(subsys_id); |
429 | ||
0628b123 PNA |
430 | while (skb->len >= nlmsg_total_size(0)) { |
431 | int msglen, type; | |
432 | ||
8a3d4c36 FW |
433 | if (fatal_signal_pending(current)) { |
434 | nfnl_err_reset(&err_list); | |
435 | err = -EINTR; | |
436 | status = NFNL_BATCH_FAILURE; | |
437 | goto done; | |
438 | } | |
439 | ||
04ba724b | 440 | memset(&extack, 0, sizeof(extack)); |
0628b123 PNA |
441 | nlh = nlmsg_hdr(skb); |
442 | err = 0; | |
443 | ||
c58d6c93 PT |
444 | if (nlh->nlmsg_len < NLMSG_HDRLEN || |
445 | skb->len < nlh->nlmsg_len || | |
446 | nlmsg_len(nlh) < sizeof(struct nfgenmsg)) { | |
447 | nfnl_err_reset(&err_list); | |
448 | status |= NFNL_BATCH_FAILURE; | |
449 | goto done; | |
0628b123 PNA |
450 | } |
451 | ||
452 | /* Only requests are handled by the kernel */ | |
453 | if (!(nlh->nlmsg_flags & NLM_F_REQUEST)) { | |
454 | err = -EINVAL; | |
455 | goto ack; | |
456 | } | |
457 | ||
458 | type = nlh->nlmsg_type; | |
459 | if (type == NFNL_MSG_BATCH_BEGIN) { | |
460 | /* Malformed: Batch begin twice */ | |
cbb8125e | 461 | nfnl_err_reset(&err_list); |
6742b9e3 | 462 | status |= NFNL_BATCH_FAILURE; |
0628b123 PNA |
463 | goto done; |
464 | } else if (type == NFNL_MSG_BATCH_END) { | |
6742b9e3 | 465 | status |= NFNL_BATCH_DONE; |
0628b123 PNA |
466 | goto done; |
467 | } else if (type < NLMSG_MIN_TYPE) { | |
468 | err = -EINVAL; | |
469 | goto ack; | |
470 | } | |
471 | ||
472 | /* We only accept a batch with messages for the same | |
473 | * subsystem. | |
474 | */ | |
475 | if (NFNL_SUBSYS_ID(type) != subsys_id) { | |
476 | err = -EINVAL; | |
477 | goto ack; | |
478 | } | |
479 | ||
480 | nc = nfnetlink_find_client(type, ss); | |
481 | if (!nc) { | |
482 | err = -EINVAL; | |
483 | goto ack; | |
484 | } | |
485 | ||
50f2db9e PNA |
486 | if (nc->type != NFNL_CB_BATCH) { |
487 | err = -EINVAL; | |
488 | goto ack; | |
489 | } | |
490 | ||
0628b123 PNA |
491 | { |
492 | int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); | |
7dab8ee3 | 493 | struct nfnl_net *nfnlnet = nfnl_pernet(net); |
7b7744e2 | 494 | struct nlattr *cda[NFNL_MAX_ATTR_COUNT + 1]; |
0628b123 | 495 | struct nlattr *attr = (void *)nlh + min_len; |
50f2db9e | 496 | u8 cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type); |
0628b123 | 497 | int attrlen = nlh->nlmsg_len - min_len; |
7dab8ee3 PNA |
498 | struct nfnl_info info = { |
499 | .net = net, | |
500 | .sk = nfnlnet->nfnl, | |
501 | .nlh = nlh, | |
ef4b65e5 | 502 | .nfmsg = nlmsg_data(nlh), |
7dab8ee3 PNA |
503 | .extack = &extack, |
504 | }; | |
0628b123 | 505 | |
7b7744e2 KC |
506 | /* Sanity-check NFTA_MAX_ATTR */ |
507 | if (ss->cb[cb_id].attr_count > NFNL_MAX_ATTR_COUNT) { | |
508 | err = -ENOMEM; | |
509 | goto ack; | |
510 | } | |
511 | ||
8cb08174 JB |
512 | err = nla_parse_deprecated(cda, |
513 | ss->cb[cb_id].attr_count, | |
514 | attr, attrlen, | |
515 | ss->cb[cb_id].policy, NULL); | |
0628b123 PNA |
516 | if (err < 0) |
517 | goto ack; | |
518 | ||
50f2db9e | 519 | err = nc->call(skb, &info, (const struct nlattr **)cda); |
0628b123 PNA |
520 | |
521 | /* The lock was released to autoload some module, we | |
522 | * have to abort and start from scratch using the | |
523 | * original skb. | |
524 | */ | |
525 | if (err == -EAGAIN) { | |
6742b9e3 | 526 | status |= NFNL_BATCH_REPLAY; |
71ad00c5 | 527 | goto done; |
0628b123 PNA |
528 | } |
529 | } | |
530 | ack: | |
531 | if (nlh->nlmsg_flags & NLM_F_ACK || err) { | |
cbb8125e PNA |
532 | /* Errors are delivered once the full batch has been |
533 | * processed, this avoids that the same error is | |
534 | * reported several times when replaying the batch. | |
535 | */ | |
04ba724b | 536 | if (nfnl_err_add(&err_list, nlh, err, &extack) < 0) { |
cbb8125e PNA |
537 | /* We failed to enqueue an error, reset the |
538 | * list of errors and send OOM to userspace | |
539 | * pointing to the batch header. | |
540 | */ | |
541 | nfnl_err_reset(&err_list); | |
2d4bc933 JB |
542 | netlink_ack(oskb, nlmsg_hdr(oskb), -ENOMEM, |
543 | NULL); | |
6742b9e3 | 544 | status |= NFNL_BATCH_FAILURE; |
cbb8125e PNA |
545 | goto done; |
546 | } | |
0628b123 PNA |
547 | /* We don't stop processing the batch on errors, thus, |
548 | * userspace gets all the errors that the batch | |
549 | * triggers. | |
550 | */ | |
0628b123 | 551 | if (err) |
6742b9e3 | 552 | status |= NFNL_BATCH_FAILURE; |
0628b123 | 553 | } |
71ad00c5 | 554 | |
0628b123 PNA |
555 | msglen = NLMSG_ALIGN(nlh->nlmsg_len); |
556 | if (msglen > skb->len) | |
557 | msglen = skb->len; | |
558 | skb_pull(skb, msglen); | |
559 | } | |
560 | done: | |
6742b9e3 | 561 | if (status & NFNL_BATCH_REPLAY) { |
c0391b6a | 562 | ss->abort(net, oskb, NFNL_ABORT_AUTOLOAD); |
6742b9e3 | 563 | nfnl_err_reset(&err_list); |
6742b9e3 | 564 | kfree_skb(skb); |
be2ab5b4 | 565 | module_put(ss->owner); |
6742b9e3 PNA |
566 | goto replay; |
567 | } else if (status == NFNL_BATCH_DONE) { | |
00308791 FW |
568 | err = ss->commit(net, oskb); |
569 | if (err == -EAGAIN) { | |
570 | status |= NFNL_BATCH_REPLAY; | |
571 | goto done; | |
572 | } else if (err) { | |
c0391b6a | 573 | ss->abort(net, oskb, NFNL_ABORT_NONE); |
00308791 FW |
574 | netlink_ack(oskb, nlmsg_hdr(oskb), err, NULL); |
575 | } | |
6742b9e3 | 576 | } else { |
c0391b6a PNA |
577 | enum nfnl_abort_action abort_action; |
578 | ||
579 | if (status & NFNL_BATCH_FAILURE) | |
580 | abort_action = NFNL_ABORT_NONE; | |
581 | else | |
582 | abort_action = NFNL_ABORT_VALIDATE; | |
583 | ||
584 | err = ss->abort(net, oskb, abort_action); | |
585 | if (err == -EAGAIN) { | |
586 | nfnl_err_reset(&err_list); | |
587 | kfree_skb(skb); | |
588 | module_put(ss->owner); | |
589 | status |= NFNL_BATCH_FAILURE; | |
590 | goto replay_abort; | |
591 | } | |
6742b9e3 | 592 | } |
0628b123 | 593 | |
cbb8125e | 594 | nfnl_err_deliver(&err_list, oskb); |
0f816232 | 595 | kfree_skb(skb); |
be2ab5b4 | 596 | module_put(ss->owner); |
0628b123 PNA |
597 | } |
598 | ||
8c4d4e8b PNA |
599 | static const struct nla_policy nfnl_batch_policy[NFNL_BATCH_MAX + 1] = { |
600 | [NFNL_BATCH_GENID] = { .type = NLA_U32 }, | |
601 | }; | |
602 | ||
48656835 | 603 | static void nfnetlink_rcv_skb_batch(struct sk_buff *skb, struct nlmsghdr *nlh) |
f9e815b3 | 604 | { |
8c4d4e8b PNA |
605 | int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); |
606 | struct nlattr *attr = (void *)nlh + min_len; | |
607 | struct nlattr *cda[NFNL_BATCH_MAX + 1]; | |
608 | int attrlen = nlh->nlmsg_len - min_len; | |
48656835 | 609 | struct nfgenmsg *nfgenmsg; |
8c4d4e8b PNA |
610 | int msglen, err; |
611 | u32 gen_id = 0; | |
b745d035 | 612 | u16 res_id; |
0628b123 | 613 | |
48656835 PNA |
614 | msglen = NLMSG_ALIGN(nlh->nlmsg_len); |
615 | if (msglen > skb->len) | |
616 | msglen = skb->len; | |
617 | ||
f55ce7b0 | 618 | if (skb->len < NLMSG_HDRLEN + sizeof(struct nfgenmsg)) |
48656835 PNA |
619 | return; |
620 | ||
8cb08174 JB |
621 | err = nla_parse_deprecated(cda, NFNL_BATCH_MAX, attr, attrlen, |
622 | nfnl_batch_policy, NULL); | |
8c4d4e8b | 623 | if (err < 0) { |
2d4bc933 | 624 | netlink_ack(skb, nlh, err, NULL); |
8c4d4e8b PNA |
625 | return; |
626 | } | |
627 | if (cda[NFNL_BATCH_GENID]) | |
628 | gen_id = ntohl(nla_get_be32(cda[NFNL_BATCH_GENID])); | |
629 | ||
48656835 PNA |
630 | nfgenmsg = nlmsg_data(nlh); |
631 | skb_pull(skb, msglen); | |
632 | /* Work around old nft using host byte order */ | |
ec6f2ff0 | 633 | if (nfgenmsg->res_id == (__force __be16)NFNL_SUBSYS_NFTABLES) |
48656835 PNA |
634 | res_id = NFNL_SUBSYS_NFTABLES; |
635 | else | |
636 | res_id = ntohs(nfgenmsg->res_id); | |
637 | ||
8c4d4e8b | 638 | nfnetlink_rcv_batch(skb, nlh, res_id, gen_id); |
48656835 PNA |
639 | } |
640 | ||
641 | static void nfnetlink_rcv(struct sk_buff *skb) | |
642 | { | |
643 | struct nlmsghdr *nlh = nlmsg_hdr(skb); | |
644 | ||
f55ce7b0 MJ |
645 | if (skb->len < NLMSG_HDRLEN || |
646 | nlh->nlmsg_len < NLMSG_HDRLEN || | |
0628b123 PNA |
647 | skb->len < nlh->nlmsg_len) |
648 | return; | |
649 | ||
90f62cf3 | 650 | if (!netlink_net_capable(skb, CAP_NET_ADMIN)) { |
2d4bc933 | 651 | netlink_ack(skb, nlh, -EPERM, NULL); |
cdbe7c2d JB |
652 | return; |
653 | } | |
654 | ||
48656835 PNA |
655 | if (nlh->nlmsg_type == NFNL_MSG_BATCH_BEGIN) |
656 | nfnetlink_rcv_skb_batch(skb, nlh); | |
657 | else | |
d4ef3835 | 658 | netlink_rcv_skb(skb, nfnetlink_rcv_msg); |
f9e815b3 HW |
659 | } |
660 | ||
0b2f3212 FW |
661 | static void nfnetlink_bind_event(struct net *net, unsigned int group) |
662 | { | |
663 | #ifdef CONFIG_NF_CONNTRACK_EVENTS | |
664 | int type, group_bit; | |
665 | u8 v; | |
666 | ||
667 | /* All NFNLGRP_CONNTRACK_* group bits fit into u8. | |
668 | * The other groups are not relevant and can be ignored. | |
669 | */ | |
670 | if (group >= 8) | |
671 | return; | |
672 | ||
673 | type = nfnl_group2type[group]; | |
674 | ||
675 | switch (type) { | |
676 | case NFNL_SUBSYS_CTNETLINK: | |
677 | break; | |
678 | case NFNL_SUBSYS_CTNETLINK_EXP: | |
679 | break; | |
680 | default: | |
681 | return; | |
682 | } | |
683 | ||
684 | group_bit = (1 << group); | |
685 | ||
686 | spin_lock(&nfnl_grp_active_lock); | |
fdf64911 | 687 | v = READ_ONCE(nf_ctnetlink_has_listener); |
0b2f3212 FW |
688 | if ((v & group_bit) == 0) { |
689 | v |= group_bit; | |
690 | ||
691 | /* read concurrently without nfnl_grp_active_lock held. */ | |
fdf64911 | 692 | WRITE_ONCE(nf_ctnetlink_has_listener, v); |
0b2f3212 FW |
693 | } |
694 | ||
695 | spin_unlock(&nfnl_grp_active_lock); | |
696 | #endif | |
697 | } | |
698 | ||
023e2cfa | 699 | static int nfnetlink_bind(struct net *net, int group) |
03292745 PNA |
700 | { |
701 | const struct nfnetlink_subsystem *ss; | |
97840cb6 PNA |
702 | int type; |
703 | ||
704 | if (group <= NFNLGRP_NONE || group > NFNLGRP_MAX) | |
62924af2 | 705 | return 0; |
97840cb6 PNA |
706 | |
707 | type = nfnl_group2type[group]; | |
03292745 PNA |
708 | |
709 | rcu_read_lock(); | |
dbc3617f | 710 | ss = nfnetlink_get_subsys(type << 8); |
03292745 | 711 | rcu_read_unlock(); |
bfe4bc71 | 712 | if (!ss) |
1b0890cd | 713 | request_module_nowait("nfnetlink-subsys-%d", type); |
2794cdb0 | 714 | |
0b2f3212 | 715 | nfnetlink_bind_event(net, group); |
4f520900 | 716 | return 0; |
03292745 | 717 | } |
2794cdb0 FW |
718 | |
719 | static void nfnetlink_unbind(struct net *net, int group) | |
720 | { | |
721 | #ifdef CONFIG_NF_CONNTRACK_EVENTS | |
0b2f3212 FW |
722 | int type, group_bit; |
723 | ||
ffd219ef FW |
724 | if (group <= NFNLGRP_NONE || group > NFNLGRP_MAX) |
725 | return; | |
2794cdb0 | 726 | |
0b2f3212 FW |
727 | type = nfnl_group2type[group]; |
728 | ||
729 | switch (type) { | |
730 | case NFNL_SUBSYS_CTNETLINK: | |
731 | break; | |
732 | case NFNL_SUBSYS_CTNETLINK_EXP: | |
733 | break; | |
734 | default: | |
735 | return; | |
736 | } | |
737 | ||
738 | /* ctnetlink_has_listener is u8 */ | |
739 | if (group >= 8) | |
740 | return; | |
741 | ||
742 | group_bit = (1 << group); | |
743 | ||
744 | spin_lock(&nfnl_grp_active_lock); | |
745 | if (!nfnetlink_has_listeners(net, group)) { | |
fdf64911 | 746 | u8 v = READ_ONCE(nf_ctnetlink_has_listener); |
0b2f3212 FW |
747 | |
748 | v &= ~group_bit; | |
749 | ||
750 | /* read concurrently without nfnl_grp_active_lock held. */ | |
fdf64911 | 751 | WRITE_ONCE(nf_ctnetlink_has_listener, v); |
2794cdb0 | 752 | } |
0b2f3212 | 753 | spin_unlock(&nfnl_grp_active_lock); |
03292745 | 754 | #endif |
2794cdb0 | 755 | } |
03292745 | 756 | |
cd8c20b6 | 757 | static int __net_init nfnetlink_net_init(struct net *net) |
f9e815b3 | 758 | { |
1be05ea7 | 759 | struct nfnl_net *nfnlnet = nfnl_pernet(net); |
a31f2d17 PNA |
760 | struct netlink_kernel_cfg cfg = { |
761 | .groups = NFNLGRP_MAX, | |
762 | .input = nfnetlink_rcv, | |
03292745 | 763 | .bind = nfnetlink_bind, |
2794cdb0 | 764 | .unbind = nfnetlink_unbind, |
a31f2d17 | 765 | }; |
cd8c20b6 | 766 | |
1be05ea7 FW |
767 | nfnlnet->nfnl = netlink_kernel_create(net, NETLINK_NETFILTER, &cfg); |
768 | if (!nfnlnet->nfnl) | |
cd8c20b6 | 769 | return -ENOMEM; |
cd8c20b6 | 770 | return 0; |
f9e815b3 HW |
771 | } |
772 | ||
cd8c20b6 | 773 | static void __net_exit nfnetlink_net_exit_batch(struct list_head *net_exit_list) |
f9e815b3 | 774 | { |
1be05ea7 | 775 | struct nfnl_net *nfnlnet; |
cd8c20b6 | 776 | struct net *net; |
f9e815b3 | 777 | |
1be05ea7 FW |
778 | list_for_each_entry(net, net_exit_list, exit_list) { |
779 | nfnlnet = nfnl_pernet(net); | |
780 | ||
781 | netlink_kernel_release(nfnlnet->nfnl); | |
782 | } | |
cd8c20b6 | 783 | } |
f9e815b3 | 784 | |
cd8c20b6 AD |
785 | static struct pernet_operations nfnetlink_net_ops = { |
786 | .init = nfnetlink_net_init, | |
787 | .exit_batch = nfnetlink_net_exit_batch, | |
1be05ea7 FW |
788 | .id = &nfnetlink_pernet_id, |
789 | .size = sizeof(struct nfnl_net), | |
cd8c20b6 AD |
790 | }; |
791 | ||
792 | static int __init nfnetlink_init(void) | |
793 | { | |
c14b78e7 PNA |
794 | int i; |
795 | ||
97840cb6 PNA |
796 | for (i = NFNLGRP_NONE + 1; i <= NFNLGRP_MAX; i++) |
797 | BUG_ON(nfnl_group2type[i] == NFNL_SUBSYS_NONE); | |
798 | ||
c14b78e7 | 799 | for (i=0; i<NFNL_SUBSYS_COUNT; i++) |
ab6c41ee | 800 | __mutex_init(&table[i].mutex, nfnl_lockdep_names[i], &nfnl_lockdep_keys[i]); |
c14b78e7 | 801 | |
cd8c20b6 | 802 | return register_pernet_subsys(&nfnetlink_net_ops); |
f9e815b3 HW |
803 | } |
804 | ||
cd8c20b6 AD |
805 | static void __exit nfnetlink_exit(void) |
806 | { | |
cd8c20b6 AD |
807 | unregister_pernet_subsys(&nfnetlink_net_ops); |
808 | } | |
f9e815b3 HW |
809 | module_init(nfnetlink_init); |
810 | module_exit(nfnetlink_exit); |