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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> |
1be05ea7 | 31 | #include <net/netns/generic.h> |
f9e815b3 HW |
32 | #include <linux/netfilter/nfnetlink.h> |
33 | ||
34 | MODULE_LICENSE("GPL"); | |
4fdb3bb7 HW |
35 | MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>"); |
36 | MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_NETFILTER); | |
4cacc395 | 37 | MODULE_DESCRIPTION("Netfilter messages via netlink socket"); |
f9e815b3 | 38 | |
9c55d3b5 FW |
39 | #define nfnl_dereference_protected(id) \ |
40 | rcu_dereference_protected(table[(id)].subsys, \ | |
41 | lockdep_nfnl_is_held((id))) | |
42 | ||
7b7744e2 KC |
43 | #define NFNL_MAX_ATTR_COUNT 32 |
44 | ||
1be05ea7 FW |
45 | static unsigned int nfnetlink_pernet_id __read_mostly; |
46 | ||
47 | struct nfnl_net { | |
48 | struct sock *nfnl; | |
49 | }; | |
50 | ||
c14b78e7 PNA |
51 | static struct { |
52 | struct mutex mutex; | |
53 | const struct nfnetlink_subsystem __rcu *subsys; | |
54 | } table[NFNL_SUBSYS_COUNT]; | |
f9e815b3 | 55 | |
ab6c41ee FW |
56 | static struct lock_class_key nfnl_lockdep_keys[NFNL_SUBSYS_COUNT]; |
57 | ||
58 | static const char *const nfnl_lockdep_names[NFNL_SUBSYS_COUNT] = { | |
59 | [NFNL_SUBSYS_NONE] = "nfnl_subsys_none", | |
60 | [NFNL_SUBSYS_CTNETLINK] = "nfnl_subsys_ctnetlink", | |
61 | [NFNL_SUBSYS_CTNETLINK_EXP] = "nfnl_subsys_ctnetlink_exp", | |
62 | [NFNL_SUBSYS_QUEUE] = "nfnl_subsys_queue", | |
63 | [NFNL_SUBSYS_ULOG] = "nfnl_subsys_ulog", | |
64 | [NFNL_SUBSYS_OSF] = "nfnl_subsys_osf", | |
65 | [NFNL_SUBSYS_IPSET] = "nfnl_subsys_ipset", | |
66 | [NFNL_SUBSYS_ACCT] = "nfnl_subsys_acct", | |
67 | [NFNL_SUBSYS_CTNETLINK_TIMEOUT] = "nfnl_subsys_cttimeout", | |
68 | [NFNL_SUBSYS_CTHELPER] = "nfnl_subsys_cthelper", | |
69 | [NFNL_SUBSYS_NFTABLES] = "nfnl_subsys_nftables", | |
70 | [NFNL_SUBSYS_NFT_COMPAT] = "nfnl_subsys_nftcompat", | |
71 | }; | |
72 | ||
03292745 PNA |
73 | static const int nfnl_group2type[NFNLGRP_MAX+1] = { |
74 | [NFNLGRP_CONNTRACK_NEW] = NFNL_SUBSYS_CTNETLINK, | |
75 | [NFNLGRP_CONNTRACK_UPDATE] = NFNL_SUBSYS_CTNETLINK, | |
76 | [NFNLGRP_CONNTRACK_DESTROY] = NFNL_SUBSYS_CTNETLINK, | |
77 | [NFNLGRP_CONNTRACK_EXP_NEW] = NFNL_SUBSYS_CTNETLINK_EXP, | |
78 | [NFNLGRP_CONNTRACK_EXP_UPDATE] = NFNL_SUBSYS_CTNETLINK_EXP, | |
79 | [NFNLGRP_CONNTRACK_EXP_DESTROY] = NFNL_SUBSYS_CTNETLINK_EXP, | |
97840cb6 PNA |
80 | [NFNLGRP_NFTABLES] = NFNL_SUBSYS_NFTABLES, |
81 | [NFNLGRP_ACCT_QUOTA] = NFNL_SUBSYS_ACCT, | |
33d5a7b1 | 82 | [NFNLGRP_NFTRACE] = NFNL_SUBSYS_NFTABLES, |
03292745 PNA |
83 | }; |
84 | ||
1be05ea7 FW |
85 | static struct nfnl_net *nfnl_pernet(struct net *net) |
86 | { | |
87 | return net_generic(net, nfnetlink_pernet_id); | |
88 | } | |
89 | ||
c14b78e7 | 90 | void nfnl_lock(__u8 subsys_id) |
f9e815b3 | 91 | { |
c14b78e7 | 92 | mutex_lock(&table[subsys_id].mutex); |
f9e815b3 | 93 | } |
e6a7d3c0 | 94 | EXPORT_SYMBOL_GPL(nfnl_lock); |
f9e815b3 | 95 | |
c14b78e7 | 96 | void nfnl_unlock(__u8 subsys_id) |
a3c5029c | 97 | { |
c14b78e7 | 98 | mutex_unlock(&table[subsys_id].mutex); |
f9e815b3 | 99 | } |
e6a7d3c0 | 100 | EXPORT_SYMBOL_GPL(nfnl_unlock); |
f9e815b3 | 101 | |
0eb5db7a | 102 | #ifdef CONFIG_PROVE_LOCKING |
875e0829 | 103 | bool lockdep_nfnl_is_held(u8 subsys_id) |
0eb5db7a PM |
104 | { |
105 | return lockdep_is_held(&table[subsys_id].mutex); | |
106 | } | |
107 | EXPORT_SYMBOL_GPL(lockdep_nfnl_is_held); | |
108 | #endif | |
109 | ||
7c8d4cb4 | 110 | int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n) |
f9e815b3 | 111 | { |
7b7744e2 KC |
112 | u8 cb_id; |
113 | ||
114 | /* Sanity-check attr_count size to avoid stack buffer overflow. */ | |
115 | for (cb_id = 0; cb_id < n->cb_count; cb_id++) | |
116 | if (WARN_ON(n->cb[cb_id].attr_count > NFNL_MAX_ATTR_COUNT)) | |
117 | return -EINVAL; | |
118 | ||
c14b78e7 PNA |
119 | nfnl_lock(n->subsys_id); |
120 | if (table[n->subsys_id].subsys) { | |
121 | nfnl_unlock(n->subsys_id); | |
0ab43f84 HW |
122 | return -EBUSY; |
123 | } | |
c14b78e7 PNA |
124 | rcu_assign_pointer(table[n->subsys_id].subsys, n); |
125 | nfnl_unlock(n->subsys_id); | |
f9e815b3 HW |
126 | |
127 | return 0; | |
128 | } | |
f4bc177f | 129 | EXPORT_SYMBOL_GPL(nfnetlink_subsys_register); |
f9e815b3 | 130 | |
7c8d4cb4 | 131 | int nfnetlink_subsys_unregister(const struct nfnetlink_subsystem *n) |
f9e815b3 | 132 | { |
c14b78e7 PNA |
133 | nfnl_lock(n->subsys_id); |
134 | table[n->subsys_id].subsys = NULL; | |
135 | nfnl_unlock(n->subsys_id); | |
6b75e3e8 | 136 | synchronize_rcu(); |
f9e815b3 HW |
137 | return 0; |
138 | } | |
f4bc177f | 139 | EXPORT_SYMBOL_GPL(nfnetlink_subsys_unregister); |
f9e815b3 | 140 | |
b745d035 | 141 | static inline const struct nfnetlink_subsystem *nfnetlink_get_subsys(u16 type) |
f9e815b3 | 142 | { |
b745d035 | 143 | u8 subsys_id = NFNL_SUBSYS_ID(type); |
f9e815b3 | 144 | |
ac0f1d98 | 145 | if (subsys_id >= NFNL_SUBSYS_COUNT) |
f9e815b3 HW |
146 | return NULL; |
147 | ||
c14b78e7 | 148 | return rcu_dereference(table[subsys_id].subsys); |
f9e815b3 HW |
149 | } |
150 | ||
7c8d4cb4 | 151 | static inline const struct nfnl_callback * |
b745d035 | 152 | nfnetlink_find_client(u16 type, const struct nfnetlink_subsystem *ss) |
f9e815b3 | 153 | { |
b745d035 | 154 | u8 cb_id = NFNL_MSG_TYPE(type); |
601e68e1 | 155 | |
67ca3966 | 156 | if (cb_id >= ss->cb_count) |
f9e815b3 | 157 | return NULL; |
f9e815b3 HW |
158 | |
159 | return &ss->cb[cb_id]; | |
160 | } | |
161 | ||
cd8c20b6 | 162 | int nfnetlink_has_listeners(struct net *net, unsigned int group) |
a2427692 | 163 | { |
1be05ea7 FW |
164 | struct nfnl_net *nfnlnet = nfnl_pernet(net); |
165 | ||
166 | return netlink_has_listeners(nfnlnet->nfnl, group); | |
a2427692 PM |
167 | } |
168 | EXPORT_SYMBOL_GPL(nfnetlink_has_listeners); | |
169 | ||
ec464e5d | 170 | int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 portid, |
95c96174 | 171 | unsigned int group, int echo, gfp_t flags) |
f9e815b3 | 172 | { |
1be05ea7 FW |
173 | struct nfnl_net *nfnlnet = nfnl_pernet(net); |
174 | ||
175 | return nlmsg_notify(nfnlnet->nfnl, skb, portid, group, echo, flags); | |
f9e815b3 | 176 | } |
f4bc177f | 177 | EXPORT_SYMBOL_GPL(nfnetlink_send); |
f9e815b3 | 178 | |
ec464e5d | 179 | int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error) |
dd5b6ce6 | 180 | { |
1be05ea7 FW |
181 | struct nfnl_net *nfnlnet = nfnl_pernet(net); |
182 | ||
183 | return netlink_set_err(nfnlnet->nfnl, portid, group, error); | |
dd5b6ce6 PNA |
184 | } |
185 | EXPORT_SYMBOL_GPL(nfnetlink_set_err); | |
186 | ||
ee921183 | 187 | int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid) |
f9e815b3 | 188 | { |
1be05ea7 | 189 | struct nfnl_net *nfnlnet = nfnl_pernet(net); |
ee921183 PNA |
190 | int err; |
191 | ||
1be05ea7 | 192 | err = nlmsg_unicast(nfnlnet->nfnl, skb, portid); |
ee921183 PNA |
193 | if (err == -EAGAIN) |
194 | err = -ENOBUFS; | |
195 | ||
196 | return err; | |
f9e815b3 | 197 | } |
f4bc177f | 198 | EXPORT_SYMBOL_GPL(nfnetlink_unicast); |
f9e815b3 | 199 | |
237c609f FW |
200 | void nfnetlink_broadcast(struct net *net, struct sk_buff *skb, __u32 portid, |
201 | __u32 group, gfp_t allocation) | |
202 | { | |
1be05ea7 FW |
203 | struct nfnl_net *nfnlnet = nfnl_pernet(net); |
204 | ||
205 | netlink_broadcast(nfnlnet->nfnl, skb, portid, group, allocation); | |
237c609f FW |
206 | } |
207 | EXPORT_SYMBOL_GPL(nfnetlink_broadcast); | |
208 | ||
f9e815b3 | 209 | /* Process one complete nfnetlink message. */ |
2d4bc933 JB |
210 | static int nfnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, |
211 | struct netlink_ext_ack *extack) | |
f9e815b3 | 212 | { |
cd8c20b6 | 213 | struct net *net = sock_net(skb->sk); |
7c8d4cb4 PM |
214 | const struct nfnl_callback *nc; |
215 | const struct nfnetlink_subsystem *ss; | |
1d00a4eb | 216 | int type, err; |
f9e815b3 | 217 | |
f9e815b3 | 218 | /* All the messages must at least contain nfgenmsg */ |
573ce260 | 219 | if (nlmsg_len(nlh) < sizeof(struct nfgenmsg)) |
f9e815b3 | 220 | return 0; |
f9e815b3 HW |
221 | |
222 | type = nlh->nlmsg_type; | |
e6a7d3c0 | 223 | replay: |
6b75e3e8 | 224 | rcu_read_lock(); |
1be05ea7 | 225 | |
f9e815b3 | 226 | ss = nfnetlink_get_subsys(type); |
0ab43f84 | 227 | if (!ss) { |
95a5afca | 228 | #ifdef CONFIG_MODULES |
6b75e3e8 | 229 | rcu_read_unlock(); |
37d2e7a2 | 230 | request_module("nfnetlink-subsys-%d", NFNL_SUBSYS_ID(type)); |
6b75e3e8 | 231 | rcu_read_lock(); |
37d2e7a2 | 232 | ss = nfnetlink_get_subsys(type); |
0ab43f84 HW |
233 | if (!ss) |
234 | #endif | |
6b75e3e8 ED |
235 | { |
236 | rcu_read_unlock(); | |
1d00a4eb | 237 | return -EINVAL; |
6b75e3e8 | 238 | } |
0ab43f84 | 239 | } |
f9e815b3 HW |
240 | |
241 | nc = nfnetlink_find_client(type, ss); | |
6b75e3e8 ED |
242 | if (!nc) { |
243 | rcu_read_unlock(); | |
1d00a4eb | 244 | return -EINVAL; |
6b75e3e8 | 245 | } |
f9e815b3 | 246 | |
f9e815b3 | 247 | { |
573ce260 | 248 | int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); |
1be05ea7 | 249 | struct nfnl_net *nfnlnet = nfnl_pernet(net); |
b745d035 | 250 | u8 cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type); |
7b7744e2 | 251 | struct nlattr *cda[NFNL_MAX_ATTR_COUNT + 1]; |
f49c857f PNA |
252 | struct nlattr *attr = (void *)nlh + min_len; |
253 | int attrlen = nlh->nlmsg_len - min_len; | |
c14b78e7 | 254 | __u8 subsys_id = NFNL_SUBSYS_ID(type); |
a6555365 PNA |
255 | struct nfnl_info info = { |
256 | .net = net, | |
257 | .sk = nfnlnet->nfnl, | |
258 | .nlh = nlh, | |
259 | .extack = extack, | |
260 | }; | |
f49c857f | 261 | |
7b7744e2 KC |
262 | /* Sanity-check NFNL_MAX_ATTR_COUNT */ |
263 | if (ss->cb[cb_id].attr_count > NFNL_MAX_ATTR_COUNT) { | |
264 | rcu_read_unlock(); | |
265 | return -ENOMEM; | |
266 | } | |
267 | ||
8cb08174 JB |
268 | err = nla_parse_deprecated(cda, ss->cb[cb_id].attr_count, |
269 | attr, attrlen, | |
270 | ss->cb[cb_id].policy, extack); | |
4009e188 TB |
271 | if (err < 0) { |
272 | rcu_read_unlock(); | |
f49c857f | 273 | return err; |
4009e188 | 274 | } |
601e68e1 | 275 | |
50f2db9e | 276 | if (!nc->call) { |
6b75e3e8 | 277 | rcu_read_unlock(); |
50f2db9e PNA |
278 | return -EINVAL; |
279 | } | |
280 | ||
281 | switch (nc->type) { | |
282 | case NFNL_CB_RCU: | |
283 | err = nc->call(skb, &info, (const struct nlattr **)cda); | |
284 | rcu_read_unlock(); | |
285 | break; | |
286 | case NFNL_CB_MUTEX: | |
6b75e3e8 | 287 | rcu_read_unlock(); |
c14b78e7 | 288 | nfnl_lock(subsys_id); |
9c55d3b5 | 289 | if (nfnl_dereference_protected(subsys_id) != ss || |
a6555365 | 290 | nfnetlink_find_client(type, ss) != nc) { |
6b75e3e8 | 291 | err = -EAGAIN; |
50f2db9e | 292 | break; |
a6555365 | 293 | } |
50f2db9e | 294 | err = nc->call(skb, &info, (const struct nlattr **)cda); |
c14b78e7 | 295 | nfnl_unlock(subsys_id); |
50f2db9e PNA |
296 | break; |
297 | default: | |
7072a355 | 298 | rcu_read_unlock(); |
50f2db9e PNA |
299 | err = -EINVAL; |
300 | break; | |
6b75e3e8 | 301 | } |
e6a7d3c0 PNA |
302 | if (err == -EAGAIN) |
303 | goto replay; | |
304 | return err; | |
f9e815b3 | 305 | } |
f9e815b3 HW |
306 | } |
307 | ||
cbb8125e PNA |
308 | struct nfnl_err { |
309 | struct list_head head; | |
310 | struct nlmsghdr *nlh; | |
311 | int err; | |
04ba724b | 312 | struct netlink_ext_ack extack; |
cbb8125e PNA |
313 | }; |
314 | ||
04ba724b PNA |
315 | static int nfnl_err_add(struct list_head *list, struct nlmsghdr *nlh, int err, |
316 | const struct netlink_ext_ack *extack) | |
cbb8125e PNA |
317 | { |
318 | struct nfnl_err *nfnl_err; | |
319 | ||
320 | nfnl_err = kmalloc(sizeof(struct nfnl_err), GFP_KERNEL); | |
321 | if (nfnl_err == NULL) | |
322 | return -ENOMEM; | |
323 | ||
324 | nfnl_err->nlh = nlh; | |
325 | nfnl_err->err = err; | |
04ba724b | 326 | nfnl_err->extack = *extack; |
cbb8125e PNA |
327 | list_add_tail(&nfnl_err->head, list); |
328 | ||
329 | return 0; | |
330 | } | |
331 | ||
332 | static void nfnl_err_del(struct nfnl_err *nfnl_err) | |
333 | { | |
334 | list_del(&nfnl_err->head); | |
335 | kfree(nfnl_err); | |
336 | } | |
337 | ||
338 | static void nfnl_err_reset(struct list_head *err_list) | |
339 | { | |
340 | struct nfnl_err *nfnl_err, *next; | |
341 | ||
342 | list_for_each_entry_safe(nfnl_err, next, err_list, head) | |
343 | nfnl_err_del(nfnl_err); | |
344 | } | |
345 | ||
346 | static void nfnl_err_deliver(struct list_head *err_list, struct sk_buff *skb) | |
347 | { | |
348 | struct nfnl_err *nfnl_err, *next; | |
349 | ||
350 | list_for_each_entry_safe(nfnl_err, next, err_list, head) { | |
04ba724b PNA |
351 | netlink_ack(skb, nfnl_err->nlh, nfnl_err->err, |
352 | &nfnl_err->extack); | |
cbb8125e PNA |
353 | nfnl_err_del(nfnl_err); |
354 | } | |
355 | } | |
356 | ||
6742b9e3 PNA |
357 | enum { |
358 | NFNL_BATCH_FAILURE = (1 << 0), | |
359 | NFNL_BATCH_DONE = (1 << 1), | |
360 | NFNL_BATCH_REPLAY = (1 << 2), | |
361 | }; | |
362 | ||
0628b123 | 363 | static void nfnetlink_rcv_batch(struct sk_buff *skb, struct nlmsghdr *nlh, |
8c4d4e8b | 364 | u16 subsys_id, u32 genid) |
0628b123 | 365 | { |
0f816232 | 366 | struct sk_buff *oskb = skb; |
0628b123 PNA |
367 | struct net *net = sock_net(skb->sk); |
368 | const struct nfnetlink_subsystem *ss; | |
369 | const struct nfnl_callback *nc; | |
04ba724b | 370 | struct netlink_ext_ack extack; |
4eba8b78 | 371 | LIST_HEAD(err_list); |
6742b9e3 | 372 | u32 status; |
0628b123 PNA |
373 | int err; |
374 | ||
375 | if (subsys_id >= NFNL_SUBSYS_COUNT) | |
2d4bc933 | 376 | return netlink_ack(skb, nlh, -EINVAL, NULL); |
0628b123 | 377 | replay: |
6742b9e3 | 378 | status = 0; |
c0391b6a | 379 | replay_abort: |
0f816232 DJ |
380 | skb = netlink_skb_clone(oskb, GFP_KERNEL); |
381 | if (!skb) | |
2d4bc933 | 382 | return netlink_ack(oskb, nlh, -ENOMEM, NULL); |
0628b123 | 383 | |
0628b123 | 384 | nfnl_lock(subsys_id); |
9c55d3b5 | 385 | ss = nfnl_dereference_protected(subsys_id); |
0628b123 PNA |
386 | if (!ss) { |
387 | #ifdef CONFIG_MODULES | |
388 | nfnl_unlock(subsys_id); | |
389 | request_module("nfnetlink-subsys-%d", subsys_id); | |
390 | nfnl_lock(subsys_id); | |
9c55d3b5 | 391 | ss = nfnl_dereference_protected(subsys_id); |
0628b123 PNA |
392 | if (!ss) |
393 | #endif | |
394 | { | |
395 | nfnl_unlock(subsys_id); | |
2d4bc933 | 396 | netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL); |
0f816232 | 397 | return kfree_skb(skb); |
0628b123 PNA |
398 | } |
399 | } | |
400 | ||
ca2f18be | 401 | if (!ss->valid_genid || !ss->commit || !ss->abort) { |
0628b123 | 402 | nfnl_unlock(subsys_id); |
2d4bc933 | 403 | netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL); |
ecd15dd7 | 404 | return kfree_skb(skb); |
0628b123 PNA |
405 | } |
406 | ||
be2ab5b4 FW |
407 | if (!try_module_get(ss->owner)) { |
408 | nfnl_unlock(subsys_id); | |
409 | netlink_ack(oskb, nlh, -EOPNOTSUPP, NULL); | |
410 | return kfree_skb(skb); | |
411 | } | |
412 | ||
ca2f18be | 413 | if (!ss->valid_genid(net, genid)) { |
be2ab5b4 | 414 | module_put(ss->owner); |
8c4d4e8b | 415 | nfnl_unlock(subsys_id); |
2d4bc933 | 416 | netlink_ack(oskb, nlh, -ERESTART, NULL); |
8c4d4e8b PNA |
417 | return kfree_skb(skb); |
418 | } | |
419 | ||
f102d66b FW |
420 | nfnl_unlock(subsys_id); |
421 | ||
0628b123 PNA |
422 | while (skb->len >= nlmsg_total_size(0)) { |
423 | int msglen, type; | |
424 | ||
8a3d4c36 FW |
425 | if (fatal_signal_pending(current)) { |
426 | nfnl_err_reset(&err_list); | |
427 | err = -EINTR; | |
428 | status = NFNL_BATCH_FAILURE; | |
429 | goto done; | |
430 | } | |
431 | ||
04ba724b | 432 | memset(&extack, 0, sizeof(extack)); |
0628b123 PNA |
433 | nlh = nlmsg_hdr(skb); |
434 | err = 0; | |
435 | ||
c58d6c93 PT |
436 | if (nlh->nlmsg_len < NLMSG_HDRLEN || |
437 | skb->len < nlh->nlmsg_len || | |
438 | nlmsg_len(nlh) < sizeof(struct nfgenmsg)) { | |
439 | nfnl_err_reset(&err_list); | |
440 | status |= NFNL_BATCH_FAILURE; | |
441 | goto done; | |
0628b123 PNA |
442 | } |
443 | ||
444 | /* Only requests are handled by the kernel */ | |
445 | if (!(nlh->nlmsg_flags & NLM_F_REQUEST)) { | |
446 | err = -EINVAL; | |
447 | goto ack; | |
448 | } | |
449 | ||
450 | type = nlh->nlmsg_type; | |
451 | if (type == NFNL_MSG_BATCH_BEGIN) { | |
452 | /* Malformed: Batch begin twice */ | |
cbb8125e | 453 | nfnl_err_reset(&err_list); |
6742b9e3 | 454 | status |= NFNL_BATCH_FAILURE; |
0628b123 PNA |
455 | goto done; |
456 | } else if (type == NFNL_MSG_BATCH_END) { | |
6742b9e3 | 457 | status |= NFNL_BATCH_DONE; |
0628b123 PNA |
458 | goto done; |
459 | } else if (type < NLMSG_MIN_TYPE) { | |
460 | err = -EINVAL; | |
461 | goto ack; | |
462 | } | |
463 | ||
464 | /* We only accept a batch with messages for the same | |
465 | * subsystem. | |
466 | */ | |
467 | if (NFNL_SUBSYS_ID(type) != subsys_id) { | |
468 | err = -EINVAL; | |
469 | goto ack; | |
470 | } | |
471 | ||
472 | nc = nfnetlink_find_client(type, ss); | |
473 | if (!nc) { | |
474 | err = -EINVAL; | |
475 | goto ack; | |
476 | } | |
477 | ||
50f2db9e PNA |
478 | if (nc->type != NFNL_CB_BATCH) { |
479 | err = -EINVAL; | |
480 | goto ack; | |
481 | } | |
482 | ||
0628b123 PNA |
483 | { |
484 | int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); | |
7dab8ee3 | 485 | struct nfnl_net *nfnlnet = nfnl_pernet(net); |
7b7744e2 | 486 | struct nlattr *cda[NFNL_MAX_ATTR_COUNT + 1]; |
0628b123 | 487 | struct nlattr *attr = (void *)nlh + min_len; |
50f2db9e | 488 | u8 cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type); |
0628b123 | 489 | int attrlen = nlh->nlmsg_len - min_len; |
7dab8ee3 PNA |
490 | struct nfnl_info info = { |
491 | .net = net, | |
492 | .sk = nfnlnet->nfnl, | |
493 | .nlh = nlh, | |
494 | .extack = &extack, | |
495 | }; | |
0628b123 | 496 | |
7b7744e2 KC |
497 | /* Sanity-check NFTA_MAX_ATTR */ |
498 | if (ss->cb[cb_id].attr_count > NFNL_MAX_ATTR_COUNT) { | |
499 | err = -ENOMEM; | |
500 | goto ack; | |
501 | } | |
502 | ||
8cb08174 JB |
503 | err = nla_parse_deprecated(cda, |
504 | ss->cb[cb_id].attr_count, | |
505 | attr, attrlen, | |
506 | ss->cb[cb_id].policy, NULL); | |
0628b123 PNA |
507 | if (err < 0) |
508 | goto ack; | |
509 | ||
50f2db9e | 510 | err = nc->call(skb, &info, (const struct nlattr **)cda); |
0628b123 PNA |
511 | |
512 | /* The lock was released to autoload some module, we | |
513 | * have to abort and start from scratch using the | |
514 | * original skb. | |
515 | */ | |
516 | if (err == -EAGAIN) { | |
6742b9e3 | 517 | status |= NFNL_BATCH_REPLAY; |
71ad00c5 | 518 | goto done; |
0628b123 PNA |
519 | } |
520 | } | |
521 | ack: | |
522 | if (nlh->nlmsg_flags & NLM_F_ACK || err) { | |
cbb8125e PNA |
523 | /* Errors are delivered once the full batch has been |
524 | * processed, this avoids that the same error is | |
525 | * reported several times when replaying the batch. | |
526 | */ | |
04ba724b | 527 | if (nfnl_err_add(&err_list, nlh, err, &extack) < 0) { |
cbb8125e PNA |
528 | /* We failed to enqueue an error, reset the |
529 | * list of errors and send OOM to userspace | |
530 | * pointing to the batch header. | |
531 | */ | |
532 | nfnl_err_reset(&err_list); | |
2d4bc933 JB |
533 | netlink_ack(oskb, nlmsg_hdr(oskb), -ENOMEM, |
534 | NULL); | |
6742b9e3 | 535 | status |= NFNL_BATCH_FAILURE; |
cbb8125e PNA |
536 | goto done; |
537 | } | |
0628b123 PNA |
538 | /* We don't stop processing the batch on errors, thus, |
539 | * userspace gets all the errors that the batch | |
540 | * triggers. | |
541 | */ | |
0628b123 | 542 | if (err) |
6742b9e3 | 543 | status |= NFNL_BATCH_FAILURE; |
0628b123 | 544 | } |
71ad00c5 | 545 | |
0628b123 PNA |
546 | msglen = NLMSG_ALIGN(nlh->nlmsg_len); |
547 | if (msglen > skb->len) | |
548 | msglen = skb->len; | |
549 | skb_pull(skb, msglen); | |
550 | } | |
551 | done: | |
6742b9e3 | 552 | if (status & NFNL_BATCH_REPLAY) { |
c0391b6a | 553 | ss->abort(net, oskb, NFNL_ABORT_AUTOLOAD); |
6742b9e3 | 554 | nfnl_err_reset(&err_list); |
6742b9e3 | 555 | kfree_skb(skb); |
be2ab5b4 | 556 | module_put(ss->owner); |
6742b9e3 PNA |
557 | goto replay; |
558 | } else if (status == NFNL_BATCH_DONE) { | |
00308791 FW |
559 | err = ss->commit(net, oskb); |
560 | if (err == -EAGAIN) { | |
561 | status |= NFNL_BATCH_REPLAY; | |
562 | goto done; | |
563 | } else if (err) { | |
c0391b6a | 564 | ss->abort(net, oskb, NFNL_ABORT_NONE); |
00308791 FW |
565 | netlink_ack(oskb, nlmsg_hdr(oskb), err, NULL); |
566 | } | |
6742b9e3 | 567 | } else { |
c0391b6a PNA |
568 | enum nfnl_abort_action abort_action; |
569 | ||
570 | if (status & NFNL_BATCH_FAILURE) | |
571 | abort_action = NFNL_ABORT_NONE; | |
572 | else | |
573 | abort_action = NFNL_ABORT_VALIDATE; | |
574 | ||
575 | err = ss->abort(net, oskb, abort_action); | |
576 | if (err == -EAGAIN) { | |
577 | nfnl_err_reset(&err_list); | |
578 | kfree_skb(skb); | |
579 | module_put(ss->owner); | |
580 | status |= NFNL_BATCH_FAILURE; | |
581 | goto replay_abort; | |
582 | } | |
6742b9e3 | 583 | } |
a654de8f PNA |
584 | if (ss->cleanup) |
585 | ss->cleanup(net); | |
0628b123 | 586 | |
cbb8125e | 587 | nfnl_err_deliver(&err_list, oskb); |
0f816232 | 588 | kfree_skb(skb); |
be2ab5b4 | 589 | module_put(ss->owner); |
0628b123 PNA |
590 | } |
591 | ||
8c4d4e8b PNA |
592 | static const struct nla_policy nfnl_batch_policy[NFNL_BATCH_MAX + 1] = { |
593 | [NFNL_BATCH_GENID] = { .type = NLA_U32 }, | |
594 | }; | |
595 | ||
48656835 | 596 | static void nfnetlink_rcv_skb_batch(struct sk_buff *skb, struct nlmsghdr *nlh) |
f9e815b3 | 597 | { |
8c4d4e8b PNA |
598 | int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); |
599 | struct nlattr *attr = (void *)nlh + min_len; | |
600 | struct nlattr *cda[NFNL_BATCH_MAX + 1]; | |
601 | int attrlen = nlh->nlmsg_len - min_len; | |
48656835 | 602 | struct nfgenmsg *nfgenmsg; |
8c4d4e8b PNA |
603 | int msglen, err; |
604 | u32 gen_id = 0; | |
b745d035 | 605 | u16 res_id; |
0628b123 | 606 | |
48656835 PNA |
607 | msglen = NLMSG_ALIGN(nlh->nlmsg_len); |
608 | if (msglen > skb->len) | |
609 | msglen = skb->len; | |
610 | ||
f55ce7b0 | 611 | if (skb->len < NLMSG_HDRLEN + sizeof(struct nfgenmsg)) |
48656835 PNA |
612 | return; |
613 | ||
8cb08174 JB |
614 | err = nla_parse_deprecated(cda, NFNL_BATCH_MAX, attr, attrlen, |
615 | nfnl_batch_policy, NULL); | |
8c4d4e8b | 616 | if (err < 0) { |
2d4bc933 | 617 | netlink_ack(skb, nlh, err, NULL); |
8c4d4e8b PNA |
618 | return; |
619 | } | |
620 | if (cda[NFNL_BATCH_GENID]) | |
621 | gen_id = ntohl(nla_get_be32(cda[NFNL_BATCH_GENID])); | |
622 | ||
48656835 PNA |
623 | nfgenmsg = nlmsg_data(nlh); |
624 | skb_pull(skb, msglen); | |
625 | /* Work around old nft using host byte order */ | |
626 | if (nfgenmsg->res_id == NFNL_SUBSYS_NFTABLES) | |
627 | res_id = NFNL_SUBSYS_NFTABLES; | |
628 | else | |
629 | res_id = ntohs(nfgenmsg->res_id); | |
630 | ||
8c4d4e8b | 631 | nfnetlink_rcv_batch(skb, nlh, res_id, gen_id); |
48656835 PNA |
632 | } |
633 | ||
634 | static void nfnetlink_rcv(struct sk_buff *skb) | |
635 | { | |
636 | struct nlmsghdr *nlh = nlmsg_hdr(skb); | |
637 | ||
f55ce7b0 MJ |
638 | if (skb->len < NLMSG_HDRLEN || |
639 | nlh->nlmsg_len < NLMSG_HDRLEN || | |
0628b123 PNA |
640 | skb->len < nlh->nlmsg_len) |
641 | return; | |
642 | ||
90f62cf3 | 643 | if (!netlink_net_capable(skb, CAP_NET_ADMIN)) { |
2d4bc933 | 644 | netlink_ack(skb, nlh, -EPERM, NULL); |
cdbe7c2d JB |
645 | return; |
646 | } | |
647 | ||
48656835 PNA |
648 | if (nlh->nlmsg_type == NFNL_MSG_BATCH_BEGIN) |
649 | nfnetlink_rcv_skb_batch(skb, nlh); | |
650 | else | |
d4ef3835 | 651 | netlink_rcv_skb(skb, nfnetlink_rcv_msg); |
f9e815b3 HW |
652 | } |
653 | ||
03292745 | 654 | #ifdef CONFIG_MODULES |
023e2cfa | 655 | static int nfnetlink_bind(struct net *net, int group) |
03292745 PNA |
656 | { |
657 | const struct nfnetlink_subsystem *ss; | |
97840cb6 PNA |
658 | int type; |
659 | ||
660 | if (group <= NFNLGRP_NONE || group > NFNLGRP_MAX) | |
62924af2 | 661 | return 0; |
97840cb6 PNA |
662 | |
663 | type = nfnl_group2type[group]; | |
03292745 PNA |
664 | |
665 | rcu_read_lock(); | |
dbc3617f | 666 | ss = nfnetlink_get_subsys(type << 8); |
03292745 | 667 | rcu_read_unlock(); |
bfe4bc71 | 668 | if (!ss) |
1b0890cd | 669 | request_module_nowait("nfnetlink-subsys-%d", type); |
4f520900 | 670 | return 0; |
03292745 PNA |
671 | } |
672 | #endif | |
673 | ||
cd8c20b6 | 674 | static int __net_init nfnetlink_net_init(struct net *net) |
f9e815b3 | 675 | { |
1be05ea7 | 676 | struct nfnl_net *nfnlnet = nfnl_pernet(net); |
a31f2d17 PNA |
677 | struct netlink_kernel_cfg cfg = { |
678 | .groups = NFNLGRP_MAX, | |
679 | .input = nfnetlink_rcv, | |
03292745 PNA |
680 | #ifdef CONFIG_MODULES |
681 | .bind = nfnetlink_bind, | |
682 | #endif | |
a31f2d17 | 683 | }; |
cd8c20b6 | 684 | |
1be05ea7 FW |
685 | nfnlnet->nfnl = netlink_kernel_create(net, NETLINK_NETFILTER, &cfg); |
686 | if (!nfnlnet->nfnl) | |
cd8c20b6 | 687 | return -ENOMEM; |
cd8c20b6 | 688 | return 0; |
f9e815b3 HW |
689 | } |
690 | ||
cd8c20b6 | 691 | static void __net_exit nfnetlink_net_exit_batch(struct list_head *net_exit_list) |
f9e815b3 | 692 | { |
1be05ea7 | 693 | struct nfnl_net *nfnlnet; |
cd8c20b6 | 694 | struct net *net; |
f9e815b3 | 695 | |
1be05ea7 FW |
696 | list_for_each_entry(net, net_exit_list, exit_list) { |
697 | nfnlnet = nfnl_pernet(net); | |
698 | ||
699 | netlink_kernel_release(nfnlnet->nfnl); | |
700 | } | |
cd8c20b6 | 701 | } |
f9e815b3 | 702 | |
cd8c20b6 AD |
703 | static struct pernet_operations nfnetlink_net_ops = { |
704 | .init = nfnetlink_net_init, | |
705 | .exit_batch = nfnetlink_net_exit_batch, | |
1be05ea7 FW |
706 | .id = &nfnetlink_pernet_id, |
707 | .size = sizeof(struct nfnl_net), | |
cd8c20b6 AD |
708 | }; |
709 | ||
710 | static int __init nfnetlink_init(void) | |
711 | { | |
c14b78e7 PNA |
712 | int i; |
713 | ||
97840cb6 PNA |
714 | for (i = NFNLGRP_NONE + 1; i <= NFNLGRP_MAX; i++) |
715 | BUG_ON(nfnl_group2type[i] == NFNL_SUBSYS_NONE); | |
716 | ||
c14b78e7 | 717 | for (i=0; i<NFNL_SUBSYS_COUNT; i++) |
ab6c41ee | 718 | __mutex_init(&table[i].mutex, nfnl_lockdep_names[i], &nfnl_lockdep_keys[i]); |
c14b78e7 | 719 | |
cd8c20b6 | 720 | return register_pernet_subsys(&nfnetlink_net_ops); |
f9e815b3 HW |
721 | } |
722 | ||
cd8c20b6 AD |
723 | static void __exit nfnetlink_exit(void) |
724 | { | |
cd8c20b6 AD |
725 | unregister_pernet_subsys(&nfnetlink_net_ops); |
726 | } | |
f9e815b3 HW |
727 | module_init(nfnetlink_init); |
728 | module_exit(nfnetlink_exit); |