Commit | Line | Data |
---|---|---|
8f03dea5 MJ |
1 | /* L3/L4 protocol support for nf_conntrack. */ |
2 | ||
3 | /* (C) 1999-2001 Paul `Rusty' Russell | |
4 | * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org> | |
5 | * (C) 2003,2004 USAGI/WIDE Project <http://www.linux-ipv6.org> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License version 2 as | |
9 | * published by the Free Software Foundation. | |
10 | */ | |
11 | ||
12 | #include <linux/types.h> | |
13 | #include <linux/netfilter.h> | |
14 | #include <linux/module.h> | |
5a0e3ad6 | 15 | #include <linux/slab.h> |
d62f9ed4 | 16 | #include <linux/mutex.h> |
8f03dea5 MJ |
17 | #include <linux/vmalloc.h> |
18 | #include <linux/stddef.h> | |
19 | #include <linux/err.h> | |
20 | #include <linux/percpu.h> | |
8f03dea5 MJ |
21 | #include <linux/notifier.h> |
22 | #include <linux/kernel.h> | |
23 | #include <linux/netdevice.h> | |
efb9a8c2 | 24 | #include <linux/rtnetlink.h> |
8f03dea5 MJ |
25 | |
26 | #include <net/netfilter/nf_conntrack.h> | |
27 | #include <net/netfilter/nf_conntrack_l3proto.h> | |
605dcad6 | 28 | #include <net/netfilter/nf_conntrack_l4proto.h> |
8f03dea5 MJ |
29 | #include <net/netfilter/nf_conntrack_core.h> |
30 | ||
42bad1da | 31 | static struct nf_conntrack_l4proto **nf_ct_protos[PF_MAX] __read_mostly; |
ae5718fb | 32 | struct nf_conntrack_l3proto *nf_ct_l3protos[AF_MAX] __read_mostly; |
13b18339 | 33 | EXPORT_SYMBOL_GPL(nf_ct_l3protos); |
8f03dea5 | 34 | |
b19caa0c | 35 | static DEFINE_MUTEX(nf_ct_proto_mutex); |
d62f9ed4 | 36 | |
b19caa0c | 37 | #ifdef CONFIG_SYSCTL |
d62f9ed4 | 38 | static int |
b3fd3ffe | 39 | nf_ct_register_sysctl(struct ctl_table_header **header, struct ctl_path *path, |
d62f9ed4 PM |
40 | struct ctl_table *table, unsigned int *users) |
41 | { | |
42 | if (*header == NULL) { | |
b3fd3ffe | 43 | *header = register_sysctl_paths(path, table); |
d62f9ed4 PM |
44 | if (*header == NULL) |
45 | return -ENOMEM; | |
46 | } | |
47 | if (users != NULL) | |
48 | (*users)++; | |
49 | return 0; | |
50 | } | |
51 | ||
52 | static void | |
53 | nf_ct_unregister_sysctl(struct ctl_table_header **header, | |
54 | struct ctl_table *table, unsigned int *users) | |
55 | { | |
56 | if (users != NULL && --*users > 0) | |
57 | return; | |
b3fd3ffe PE |
58 | |
59 | unregister_sysctl_table(*header); | |
d62f9ed4 PM |
60 | *header = NULL; |
61 | } | |
62 | #endif | |
63 | ||
605dcad6 MJ |
64 | struct nf_conntrack_l4proto * |
65 | __nf_ct_l4proto_find(u_int16_t l3proto, u_int8_t l4proto) | |
8f03dea5 MJ |
66 | { |
67 | if (unlikely(l3proto >= AF_MAX || nf_ct_protos[l3proto] == NULL)) | |
605dcad6 | 68 | return &nf_conntrack_l4proto_generic; |
8f03dea5 | 69 | |
923f4902 | 70 | return rcu_dereference(nf_ct_protos[l3proto][l4proto]); |
8f03dea5 | 71 | } |
13b18339 | 72 | EXPORT_SYMBOL_GPL(__nf_ct_l4proto_find); |
8f03dea5 MJ |
73 | |
74 | /* this is guaranteed to always return a valid protocol helper, since | |
75 | * it falls back to generic_protocol */ | |
8f03dea5 MJ |
76 | struct nf_conntrack_l3proto * |
77 | nf_ct_l3proto_find_get(u_int16_t l3proto) | |
78 | { | |
79 | struct nf_conntrack_l3proto *p; | |
80 | ||
923f4902 | 81 | rcu_read_lock(); |
8f03dea5 MJ |
82 | p = __nf_ct_l3proto_find(l3proto); |
83 | if (!try_module_get(p->me)) | |
605dcad6 | 84 | p = &nf_conntrack_l3proto_generic; |
923f4902 | 85 | rcu_read_unlock(); |
8f03dea5 MJ |
86 | |
87 | return p; | |
88 | } | |
13b18339 | 89 | EXPORT_SYMBOL_GPL(nf_ct_l3proto_find_get); |
8f03dea5 MJ |
90 | |
91 | void nf_ct_l3proto_put(struct nf_conntrack_l3proto *p) | |
92 | { | |
93 | module_put(p->me); | |
94 | } | |
13b18339 | 95 | EXPORT_SYMBOL_GPL(nf_ct_l3proto_put); |
8f03dea5 MJ |
96 | |
97 | int | |
98 | nf_ct_l3proto_try_module_get(unsigned short l3proto) | |
99 | { | |
100 | int ret; | |
101 | struct nf_conntrack_l3proto *p; | |
102 | ||
103 | retry: p = nf_ct_l3proto_find_get(l3proto); | |
605dcad6 | 104 | if (p == &nf_conntrack_l3proto_generic) { |
8f03dea5 MJ |
105 | ret = request_module("nf_conntrack-%d", l3proto); |
106 | if (!ret) | |
107 | goto retry; | |
108 | ||
109 | return -EPROTOTYPE; | |
110 | } | |
111 | ||
112 | return 0; | |
113 | } | |
13b18339 | 114 | EXPORT_SYMBOL_GPL(nf_ct_l3proto_try_module_get); |
8f03dea5 MJ |
115 | |
116 | void nf_ct_l3proto_module_put(unsigned short l3proto) | |
117 | { | |
118 | struct nf_conntrack_l3proto *p; | |
119 | ||
923f4902 | 120 | /* rcu_read_lock not necessary since the caller holds a reference */ |
8f03dea5 | 121 | p = __nf_ct_l3proto_find(l3proto); |
8f03dea5 MJ |
122 | module_put(p->me); |
123 | } | |
13b18339 | 124 | EXPORT_SYMBOL_GPL(nf_ct_l3proto_module_put); |
8f03dea5 MJ |
125 | |
126 | static int kill_l3proto(struct nf_conn *i, void *data) | |
127 | { | |
5e8fbe2a | 128 | return nf_ct_l3num(i) == ((struct nf_conntrack_l3proto *)data)->l3proto; |
8f03dea5 MJ |
129 | } |
130 | ||
605dcad6 | 131 | static int kill_l4proto(struct nf_conn *i, void *data) |
8f03dea5 | 132 | { |
605dcad6 MJ |
133 | struct nf_conntrack_l4proto *l4proto; |
134 | l4proto = (struct nf_conntrack_l4proto *)data; | |
5e8fbe2a PM |
135 | return nf_ct_protonum(i) == l4proto->l4proto && |
136 | nf_ct_l3num(i) == l4proto->l3proto; | |
8f03dea5 MJ |
137 | } |
138 | ||
d62f9ed4 PM |
139 | static int nf_ct_l3proto_register_sysctl(struct nf_conntrack_l3proto *l3proto) |
140 | { | |
141 | int err = 0; | |
142 | ||
143 | #ifdef CONFIG_SYSCTL | |
d62f9ed4 PM |
144 | if (l3proto->ctl_table != NULL) { |
145 | err = nf_ct_register_sysctl(&l3proto->ctl_table_header, | |
146 | l3proto->ctl_table_path, | |
147 | l3proto->ctl_table, NULL); | |
148 | } | |
d62f9ed4 PM |
149 | #endif |
150 | return err; | |
151 | } | |
152 | ||
153 | static void nf_ct_l3proto_unregister_sysctl(struct nf_conntrack_l3proto *l3proto) | |
154 | { | |
155 | #ifdef CONFIG_SYSCTL | |
d62f9ed4 PM |
156 | if (l3proto->ctl_table_header != NULL) |
157 | nf_ct_unregister_sysctl(&l3proto->ctl_table_header, | |
158 | l3proto->ctl_table, NULL); | |
d62f9ed4 PM |
159 | #endif |
160 | } | |
161 | ||
8f03dea5 MJ |
162 | int nf_conntrack_l3proto_register(struct nf_conntrack_l3proto *proto) |
163 | { | |
164 | int ret = 0; | |
165 | ||
0661cca9 PM |
166 | if (proto->l3proto >= AF_MAX) |
167 | return -EBUSY; | |
ae5718fb | 168 | |
d0dba725 HE |
169 | if (proto->tuple_to_nlattr && !proto->nlattr_tuple_size) |
170 | return -EINVAL; | |
171 | ||
b19caa0c | 172 | mutex_lock(&nf_ct_proto_mutex); |
605dcad6 | 173 | if (nf_ct_l3protos[proto->l3proto] != &nf_conntrack_l3proto_generic) { |
8f03dea5 | 174 | ret = -EBUSY; |
ae5718fb | 175 | goto out_unlock; |
8f03dea5 | 176 | } |
d62f9ed4 PM |
177 | |
178 | ret = nf_ct_l3proto_register_sysctl(proto); | |
179 | if (ret < 0) | |
0661cca9 PM |
180 | goto out_unlock; |
181 | ||
d0dba725 HE |
182 | if (proto->nlattr_tuple_size) |
183 | proto->nla_size = 3 * proto->nlattr_tuple_size(); | |
184 | ||
0661cca9 | 185 | rcu_assign_pointer(nf_ct_l3protos[proto->l3proto], proto); |
8f03dea5 | 186 | |
ae5718fb | 187 | out_unlock: |
b19caa0c | 188 | mutex_unlock(&nf_ct_proto_mutex); |
8f03dea5 MJ |
189 | return ret; |
190 | } | |
13b18339 | 191 | EXPORT_SYMBOL_GPL(nf_conntrack_l3proto_register); |
8f03dea5 | 192 | |
fe3eb20c | 193 | void nf_conntrack_l3proto_unregister(struct nf_conntrack_l3proto *proto) |
8f03dea5 | 194 | { |
678d6675 AD |
195 | struct net *net; |
196 | ||
fe3eb20c | 197 | BUG_ON(proto->l3proto >= AF_MAX); |
ae5718fb | 198 | |
b19caa0c | 199 | mutex_lock(&nf_ct_proto_mutex); |
fe3eb20c | 200 | BUG_ON(nf_ct_l3protos[proto->l3proto] != proto); |
923f4902 PM |
201 | rcu_assign_pointer(nf_ct_l3protos[proto->l3proto], |
202 | &nf_conntrack_l3proto_generic); | |
0661cca9 | 203 | nf_ct_l3proto_unregister_sysctl(proto); |
b19caa0c | 204 | mutex_unlock(&nf_ct_proto_mutex); |
8f03dea5 | 205 | |
0661cca9 | 206 | synchronize_rcu(); |
d62f9ed4 | 207 | |
8f03dea5 | 208 | /* Remove all contrack entries for this protocol */ |
efb9a8c2 | 209 | rtnl_lock(); |
678d6675 AD |
210 | for_each_net(net) |
211 | nf_ct_iterate_cleanup(net, kill_l3proto, proto); | |
efb9a8c2 | 212 | rtnl_unlock(); |
8f03dea5 | 213 | } |
13b18339 | 214 | EXPORT_SYMBOL_GPL(nf_conntrack_l3proto_unregister); |
8f03dea5 | 215 | |
d62f9ed4 PM |
216 | static int nf_ct_l4proto_register_sysctl(struct nf_conntrack_l4proto *l4proto) |
217 | { | |
218 | int err = 0; | |
219 | ||
220 | #ifdef CONFIG_SYSCTL | |
d62f9ed4 PM |
221 | if (l4proto->ctl_table != NULL) { |
222 | err = nf_ct_register_sysctl(l4proto->ctl_table_header, | |
223 | nf_net_netfilter_sysctl_path, | |
224 | l4proto->ctl_table, | |
225 | l4proto->ctl_table_users); | |
a999e683 PM |
226 | if (err < 0) |
227 | goto out; | |
d62f9ed4 | 228 | } |
a999e683 PM |
229 | #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT |
230 | if (l4proto->ctl_compat_table != NULL) { | |
231 | err = nf_ct_register_sysctl(&l4proto->ctl_compat_table_header, | |
232 | nf_net_ipv4_netfilter_sysctl_path, | |
233 | l4proto->ctl_compat_table, NULL); | |
234 | if (err == 0) | |
235 | goto out; | |
236 | nf_ct_unregister_sysctl(l4proto->ctl_table_header, | |
237 | l4proto->ctl_table, | |
238 | l4proto->ctl_table_users); | |
239 | } | |
240 | #endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */ | |
241 | out: | |
933a41e7 | 242 | #endif /* CONFIG_SYSCTL */ |
d62f9ed4 PM |
243 | return err; |
244 | } | |
245 | ||
246 | static void nf_ct_l4proto_unregister_sysctl(struct nf_conntrack_l4proto *l4proto) | |
247 | { | |
248 | #ifdef CONFIG_SYSCTL | |
d62f9ed4 PM |
249 | if (l4proto->ctl_table_header != NULL && |
250 | *l4proto->ctl_table_header != NULL) | |
251 | nf_ct_unregister_sysctl(l4proto->ctl_table_header, | |
252 | l4proto->ctl_table, | |
253 | l4proto->ctl_table_users); | |
a999e683 PM |
254 | #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT |
255 | if (l4proto->ctl_compat_table_header != NULL) | |
256 | nf_ct_unregister_sysctl(&l4proto->ctl_compat_table_header, | |
257 | l4proto->ctl_compat_table, NULL); | |
258 | #endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */ | |
933a41e7 | 259 | #endif /* CONFIG_SYSCTL */ |
d62f9ed4 PM |
260 | } |
261 | ||
8f03dea5 MJ |
262 | /* FIXME: Allow NULL functions and sub in pointers to generic for |
263 | them. --RR */ | |
605dcad6 | 264 | int nf_conntrack_l4proto_register(struct nf_conntrack_l4proto *l4proto) |
8f03dea5 MJ |
265 | { |
266 | int ret = 0; | |
267 | ||
0661cca9 PM |
268 | if (l4proto->l3proto >= PF_MAX) |
269 | return -EBUSY; | |
ae5718fb | 270 | |
d0dba725 HE |
271 | if ((l4proto->to_nlattr && !l4proto->nlattr_size) |
272 | || (l4proto->tuple_to_nlattr && !l4proto->nlattr_tuple_size)) | |
273 | return -EINVAL; | |
274 | ||
b19caa0c | 275 | mutex_lock(&nf_ct_proto_mutex); |
c6a1e615 | 276 | if (!nf_ct_protos[l4proto->l3proto]) { |
8f03dea5 | 277 | /* l3proto may be loaded latter. */ |
605dcad6 | 278 | struct nf_conntrack_l4proto **proto_array; |
8f03dea5 MJ |
279 | int i; |
280 | ||
c6a1e615 PM |
281 | proto_array = kmalloc(MAX_NF_CT_PROTO * |
282 | sizeof(struct nf_conntrack_l4proto *), | |
283 | GFP_KERNEL); | |
8f03dea5 MJ |
284 | if (proto_array == NULL) { |
285 | ret = -ENOMEM; | |
b19caa0c | 286 | goto out_unlock; |
8f03dea5 | 287 | } |
c6a1e615 | 288 | |
8f03dea5 | 289 | for (i = 0; i < MAX_NF_CT_PROTO; i++) |
605dcad6 | 290 | proto_array[i] = &nf_conntrack_l4proto_generic; |
c6a1e615 PM |
291 | nf_ct_protos[l4proto->l3proto] = proto_array; |
292 | } else if (nf_ct_protos[l4proto->l3proto][l4proto->l4proto] != | |
293 | &nf_conntrack_l4proto_generic) { | |
294 | ret = -EBUSY; | |
295 | goto out_unlock; | |
8f03dea5 MJ |
296 | } |
297 | ||
d62f9ed4 PM |
298 | ret = nf_ct_l4proto_register_sysctl(l4proto); |
299 | if (ret < 0) | |
0661cca9 PM |
300 | goto out_unlock; |
301 | ||
d0dba725 HE |
302 | l4proto->nla_size = 0; |
303 | if (l4proto->nlattr_size) | |
304 | l4proto->nla_size += l4proto->nlattr_size(); | |
305 | if (l4proto->nlattr_tuple_size) | |
306 | l4proto->nla_size += 3 * l4proto->nlattr_tuple_size(); | |
307 | ||
c6a1e615 PM |
308 | rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto], |
309 | l4proto); | |
8f03dea5 MJ |
310 | |
311 | out_unlock: | |
b19caa0c | 312 | mutex_unlock(&nf_ct_proto_mutex); |
8f03dea5 MJ |
313 | return ret; |
314 | } | |
13b18339 | 315 | EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_register); |
8f03dea5 | 316 | |
fe3eb20c | 317 | void nf_conntrack_l4proto_unregister(struct nf_conntrack_l4proto *l4proto) |
8f03dea5 | 318 | { |
678d6675 AD |
319 | struct net *net; |
320 | ||
fe3eb20c | 321 | BUG_ON(l4proto->l3proto >= PF_MAX); |
ae5718fb | 322 | |
b19caa0c | 323 | mutex_lock(&nf_ct_proto_mutex); |
fe3eb20c | 324 | BUG_ON(nf_ct_protos[l4proto->l3proto][l4proto->l4proto] != l4proto); |
923f4902 PM |
325 | rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto], |
326 | &nf_conntrack_l4proto_generic); | |
0661cca9 | 327 | nf_ct_l4proto_unregister_sysctl(l4proto); |
b19caa0c | 328 | mutex_unlock(&nf_ct_proto_mutex); |
8f03dea5 | 329 | |
0661cca9 | 330 | synchronize_rcu(); |
d62f9ed4 | 331 | |
8f03dea5 | 332 | /* Remove all contrack entries for this protocol */ |
efb9a8c2 | 333 | rtnl_lock(); |
678d6675 AD |
334 | for_each_net(net) |
335 | nf_ct_iterate_cleanup(net, kill_l4proto, l4proto); | |
efb9a8c2 | 336 | rtnl_unlock(); |
8f03dea5 | 337 | } |
13b18339 | 338 | EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_unregister); |
ac5357eb PM |
339 | |
340 | int nf_conntrack_proto_init(void) | |
341 | { | |
342 | unsigned int i; | |
343 | int err; | |
344 | ||
345 | err = nf_ct_l4proto_register_sysctl(&nf_conntrack_l4proto_generic); | |
346 | if (err < 0) | |
347 | return err; | |
348 | ||
349 | for (i = 0; i < AF_MAX; i++) | |
350 | rcu_assign_pointer(nf_ct_l3protos[i], | |
351 | &nf_conntrack_l3proto_generic); | |
352 | return 0; | |
353 | } | |
354 | ||
355 | void nf_conntrack_proto_fini(void) | |
356 | { | |
357 | unsigned int i; | |
358 | ||
359 | nf_ct_l4proto_unregister_sysctl(&nf_conntrack_l4proto_generic); | |
360 | ||
361 | /* free l3proto protocol tables */ | |
362 | for (i = 0; i < PF_MAX; i++) | |
363 | kfree(nf_ct_protos[i]); | |
364 | } |