Commit | Line | Data |
---|---|---|
7e5d03bb MJ |
1 | /* Helper handling for netfilter. */ |
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> | |
f229f6ce | 6 | * (C) 2006-2012 Patrick McHardy <kaber@trash.net> |
7e5d03bb MJ |
7 | * |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License version 2 as | |
10 | * published by the Free Software Foundation. | |
11 | */ | |
12 | ||
13 | #include <linux/types.h> | |
14 | #include <linux/netfilter.h> | |
15 | #include <linux/module.h> | |
16 | #include <linux/skbuff.h> | |
17 | #include <linux/vmalloc.h> | |
18 | #include <linux/stddef.h> | |
7e5d03bb MJ |
19 | #include <linux/random.h> |
20 | #include <linux/err.h> | |
21 | #include <linux/kernel.h> | |
22 | #include <linux/netdevice.h> | |
2ba4cc31 | 23 | #include <linux/rculist.h> |
efb9a8c2 | 24 | #include <linux/rtnetlink.h> |
7e5d03bb | 25 | |
7e5d03bb | 26 | #include <net/netfilter/nf_conntrack.h> |
605dcad6 | 27 | #include <net/netfilter/nf_conntrack_l4proto.h> |
7e5d03bb MJ |
28 | #include <net/netfilter/nf_conntrack_helper.h> |
29 | #include <net/netfilter/nf_conntrack_core.h> | |
ceceae1b | 30 | #include <net/netfilter/nf_conntrack_extend.h> |
b20ab9cc | 31 | #include <net/netfilter/nf_log.h> |
7e5d03bb | 32 | |
58a3c9bb | 33 | static DEFINE_MUTEX(nf_ct_helper_mutex); |
12f7a505 PNA |
34 | struct hlist_head *nf_ct_helper_hash __read_mostly; |
35 | EXPORT_SYMBOL_GPL(nf_ct_helper_hash); | |
36 | unsigned int nf_ct_helper_hsize __read_mostly; | |
37 | EXPORT_SYMBOL_GPL(nf_ct_helper_hsize); | |
b8a7fe6c | 38 | static unsigned int nf_ct_helper_count __read_mostly; |
b8a7fe6c | 39 | |
3bb398d9 | 40 | static bool nf_ct_auto_assign_helper __read_mostly = false; |
a9006892 EL |
41 | module_param_named(nf_conntrack_helper, nf_ct_auto_assign_helper, bool, 0644); |
42 | MODULE_PARM_DESC(nf_conntrack_helper, | |
3bb398d9 | 43 | "Enable automatic conntrack helper assignment (default 0)"); |
a9006892 | 44 | |
b8a7fe6c PM |
45 | /* Stupid hash, but collision free for the default registrations of the |
46 | * helpers currently in the kernel. */ | |
47 | static unsigned int helper_hash(const struct nf_conntrack_tuple *tuple) | |
48 | { | |
49 | return (((tuple->src.l3num << 8) | tuple->dst.protonum) ^ | |
a34c4589 | 50 | (__force __u16)tuple->src.u.all) % nf_ct_helper_hsize; |
b8a7fe6c | 51 | } |
7e5d03bb | 52 | |
226c0c0e | 53 | static struct nf_conntrack_helper * |
7e5d03bb MJ |
54 | __nf_ct_helper_find(const struct nf_conntrack_tuple *tuple) |
55 | { | |
b8a7fe6c | 56 | struct nf_conntrack_helper *helper; |
d4156e8c | 57 | struct nf_conntrack_tuple_mask mask = { .src.u.all = htons(0xFFFF) }; |
b8a7fe6c | 58 | unsigned int h; |
7e5d03bb | 59 | |
b8a7fe6c PM |
60 | if (!nf_ct_helper_count) |
61 | return NULL; | |
62 | ||
63 | h = helper_hash(tuple); | |
b67bfe0d | 64 | hlist_for_each_entry_rcu(helper, &nf_ct_helper_hash[h], hnode) { |
b8a7fe6c PM |
65 | if (nf_ct_tuple_src_mask_cmp(tuple, &helper->tuple, &mask)) |
66 | return helper; | |
7e5d03bb MJ |
67 | } |
68 | return NULL; | |
69 | } | |
7e5d03bb MJ |
70 | |
71 | struct nf_conntrack_helper * | |
794e6871 | 72 | __nf_conntrack_helper_find(const char *name, u16 l3num, u8 protonum) |
7e5d03bb MJ |
73 | { |
74 | struct nf_conntrack_helper *h; | |
b8a7fe6c | 75 | unsigned int i; |
7e5d03bb | 76 | |
b8a7fe6c | 77 | for (i = 0; i < nf_ct_helper_hsize; i++) { |
b67bfe0d | 78 | hlist_for_each_entry_rcu(h, &nf_ct_helper_hash[i], hnode) { |
6114cc51 FW |
79 | if (strcmp(h->name, name)) |
80 | continue; | |
81 | ||
82 | if (h->tuple.src.l3num != NFPROTO_UNSPEC && | |
83 | h->tuple.src.l3num != l3num) | |
84 | continue; | |
85 | ||
86 | if (h->tuple.dst.protonum == protonum) | |
b8a7fe6c PM |
87 | return h; |
88 | } | |
7e5d03bb | 89 | } |
7e5d03bb MJ |
90 | return NULL; |
91 | } | |
794e6871 | 92 | EXPORT_SYMBOL_GPL(__nf_conntrack_helper_find); |
7e5d03bb | 93 | |
84f3bb9a PM |
94 | struct nf_conntrack_helper * |
95 | nf_conntrack_helper_try_module_get(const char *name, u16 l3num, u8 protonum) | |
96 | { | |
97 | struct nf_conntrack_helper *h; | |
98 | ||
8b5995d0 GF |
99 | rcu_read_lock(); |
100 | ||
84f3bb9a PM |
101 | h = __nf_conntrack_helper_find(name, l3num, protonum); |
102 | #ifdef CONFIG_MODULES | |
103 | if (h == NULL) { | |
8b5995d0 GF |
104 | rcu_read_unlock(); |
105 | if (request_module("nfct-helper-%s", name) == 0) { | |
106 | rcu_read_lock(); | |
84f3bb9a | 107 | h = __nf_conntrack_helper_find(name, l3num, protonum); |
8b5995d0 GF |
108 | } else { |
109 | return h; | |
110 | } | |
84f3bb9a PM |
111 | } |
112 | #endif | |
113 | if (h != NULL && !try_module_get(h->me)) | |
114 | h = NULL; | |
9338d7b4 LZ |
115 | if (h != NULL && !refcount_inc_not_zero(&h->refcnt)) { |
116 | module_put(h->me); | |
117 | h = NULL; | |
118 | } | |
84f3bb9a | 119 | |
8b5995d0 GF |
120 | rcu_read_unlock(); |
121 | ||
84f3bb9a PM |
122 | return h; |
123 | } | |
124 | EXPORT_SYMBOL_GPL(nf_conntrack_helper_try_module_get); | |
125 | ||
d91fc59c LZ |
126 | void nf_conntrack_helper_put(struct nf_conntrack_helper *helper) |
127 | { | |
9338d7b4 | 128 | refcount_dec(&helper->refcnt); |
d91fc59c LZ |
129 | module_put(helper->me); |
130 | } | |
131 | EXPORT_SYMBOL_GPL(nf_conntrack_helper_put); | |
132 | ||
1afc5679 | 133 | struct nf_conn_help * |
440534d3 | 134 | nf_ct_helper_ext_add(struct nf_conn *ct, gfp_t gfp) |
b560580a PM |
135 | { |
136 | struct nf_conn_help *help; | |
137 | ||
9f0f3ebe | 138 | help = nf_ct_ext_add(ct, NF_CT_EXT_HELPER, gfp); |
b560580a PM |
139 | if (help) |
140 | INIT_HLIST_HEAD(&help->expectations); | |
141 | else | |
142 | pr_debug("failed to add helper extension area"); | |
143 | return help; | |
144 | } | |
145 | EXPORT_SYMBOL_GPL(nf_ct_helper_ext_add); | |
146 | ||
dfe75ff8 JK |
147 | static struct nf_conntrack_helper * |
148 | nf_ct_lookup_helper(struct nf_conn *ct, struct net *net) | |
149 | { | |
150 | if (!net->ct.sysctl_auto_assign_helper) { | |
151 | if (net->ct.auto_assign_helper_warned) | |
152 | return NULL; | |
153 | if (!__nf_ct_helper_find(&ct->tuplehash[IP_CT_DIR_REPLY].tuple)) | |
154 | return NULL; | |
155 | pr_info("nf_conntrack: default automatic helper assignment " | |
156 | "has been turned off for security reasons and CT-based " | |
157 | " firewall rule not found. Use the iptables CT target " | |
158 | "to attach helpers instead.\n"); | |
159 | net->ct.auto_assign_helper_warned = 1; | |
160 | return NULL; | |
161 | } | |
162 | ||
163 | return __nf_ct_helper_find(&ct->tuplehash[IP_CT_DIR_REPLY].tuple); | |
164 | } | |
165 | ||
166 | ||
b2a15a60 PM |
167 | int __nf_ct_try_assign_helper(struct nf_conn *ct, struct nf_conn *tmpl, |
168 | gfp_t flags) | |
226c0c0e | 169 | { |
b2a15a60 PM |
170 | struct nf_conntrack_helper *helper = NULL; |
171 | struct nf_conn_help *help; | |
a9006892 | 172 | struct net *net = nf_ct_net(ct); |
226c0c0e | 173 | |
6714cf54 PNA |
174 | /* We already got a helper explicitly attached. The function |
175 | * nf_conntrack_alter_reply - in case NAT is in use - asks for looking | |
176 | * the helper up again. Since now the user is in full control of | |
177 | * making consistent helper configurations, skip this automatic | |
178 | * re-lookup, otherwise we'll lose the helper. | |
179 | */ | |
180 | if (test_bit(IPS_HELPER_BIT, &ct->status)) | |
181 | return 0; | |
182 | ||
b2a15a60 PM |
183 | if (tmpl != NULL) { |
184 | help = nfct_help(tmpl); | |
6714cf54 | 185 | if (help != NULL) { |
b2a15a60 | 186 | helper = help->helper; |
6714cf54 PNA |
187 | set_bit(IPS_HELPER_BIT, &ct->status); |
188 | } | |
b2a15a60 PM |
189 | } |
190 | ||
191 | help = nfct_help(ct); | |
a9006892 | 192 | |
226c0c0e | 193 | if (helper == NULL) { |
dfe75ff8 JK |
194 | helper = nf_ct_lookup_helper(ct, net); |
195 | if (helper == NULL) { | |
196 | if (help) | |
197 | RCU_INIT_POINTER(help->helper, NULL); | |
198 | return 0; | |
199 | } | |
226c0c0e PNA |
200 | } |
201 | ||
202 | if (help == NULL) { | |
440534d3 | 203 | help = nf_ct_helper_ext_add(ct, flags); |
cf71c03e PN |
204 | if (help == NULL) |
205 | return -ENOMEM; | |
226c0c0e | 206 | } else { |
32f53760 PNA |
207 | /* We only allow helper re-assignment of the same sort since |
208 | * we cannot reallocate the helper extension area. | |
209 | */ | |
6e2f0aa8 FW |
210 | struct nf_conntrack_helper *tmp = rcu_dereference(help->helper); |
211 | ||
212 | if (tmp && tmp->help != helper->help) { | |
32f53760 | 213 | RCU_INIT_POINTER(help->helper, NULL); |
cf71c03e | 214 | return 0; |
32f53760 | 215 | } |
226c0c0e PNA |
216 | } |
217 | ||
cf778b00 | 218 | rcu_assign_pointer(help->helper, helper); |
cf71c03e PN |
219 | |
220 | return 0; | |
226c0c0e PNA |
221 | } |
222 | EXPORT_SYMBOL_GPL(__nf_ct_try_assign_helper); | |
223 | ||
01cfa0a4 | 224 | /* appropriate ct lock protecting must be taken by caller */ |
ff1acc49 | 225 | static int unhelp(struct nf_conn *ct, void *me) |
7e5d03bb | 226 | { |
7e5d03bb MJ |
227 | struct nf_conn_help *help = nfct_help(ct); |
228 | ||
ca7433df | 229 | if (help && rcu_dereference_raw(help->helper) == me) { |
7e5d03bb | 230 | nf_conntrack_event(IPCT_HELPER, ct); |
a9b3cd7f | 231 | RCU_INIT_POINTER(help->helper, NULL); |
7e5d03bb | 232 | } |
ff1acc49 LZ |
233 | |
234 | /* We are not intended to delete this conntrack. */ | |
7e5d03bb MJ |
235 | return 0; |
236 | } | |
237 | ||
9858a3ae PNA |
238 | void nf_ct_helper_destroy(struct nf_conn *ct) |
239 | { | |
240 | struct nf_conn_help *help = nfct_help(ct); | |
241 | struct nf_conntrack_helper *helper; | |
242 | ||
243 | if (help) { | |
244 | rcu_read_lock(); | |
245 | helper = rcu_dereference(help->helper); | |
246 | if (helper && helper->destroy) | |
247 | helper->destroy(ct); | |
248 | rcu_read_unlock(); | |
249 | } | |
250 | } | |
251 | ||
544d5c7d PNA |
252 | static LIST_HEAD(nf_ct_helper_expectfn_list); |
253 | ||
254 | void nf_ct_helper_expectfn_register(struct nf_ct_helper_expectfn *n) | |
255 | { | |
ca7433df | 256 | spin_lock_bh(&nf_conntrack_expect_lock); |
544d5c7d | 257 | list_add_rcu(&n->head, &nf_ct_helper_expectfn_list); |
ca7433df | 258 | spin_unlock_bh(&nf_conntrack_expect_lock); |
544d5c7d PNA |
259 | } |
260 | EXPORT_SYMBOL_GPL(nf_ct_helper_expectfn_register); | |
261 | ||
262 | void nf_ct_helper_expectfn_unregister(struct nf_ct_helper_expectfn *n) | |
263 | { | |
ca7433df | 264 | spin_lock_bh(&nf_conntrack_expect_lock); |
544d5c7d | 265 | list_del_rcu(&n->head); |
ca7433df | 266 | spin_unlock_bh(&nf_conntrack_expect_lock); |
544d5c7d PNA |
267 | } |
268 | EXPORT_SYMBOL_GPL(nf_ct_helper_expectfn_unregister); | |
269 | ||
8b5995d0 | 270 | /* Caller should hold the rcu lock */ |
544d5c7d PNA |
271 | struct nf_ct_helper_expectfn * |
272 | nf_ct_helper_expectfn_find_by_name(const char *name) | |
273 | { | |
274 | struct nf_ct_helper_expectfn *cur; | |
275 | bool found = false; | |
276 | ||
544d5c7d PNA |
277 | list_for_each_entry_rcu(cur, &nf_ct_helper_expectfn_list, head) { |
278 | if (!strcmp(cur->name, name)) { | |
279 | found = true; | |
280 | break; | |
281 | } | |
282 | } | |
544d5c7d PNA |
283 | return found ? cur : NULL; |
284 | } | |
285 | EXPORT_SYMBOL_GPL(nf_ct_helper_expectfn_find_by_name); | |
286 | ||
8b5995d0 | 287 | /* Caller should hold the rcu lock */ |
544d5c7d PNA |
288 | struct nf_ct_helper_expectfn * |
289 | nf_ct_helper_expectfn_find_by_symbol(const void *symbol) | |
290 | { | |
291 | struct nf_ct_helper_expectfn *cur; | |
292 | bool found = false; | |
293 | ||
544d5c7d PNA |
294 | list_for_each_entry_rcu(cur, &nf_ct_helper_expectfn_list, head) { |
295 | if (cur->expectfn == symbol) { | |
296 | found = true; | |
297 | break; | |
298 | } | |
299 | } | |
544d5c7d PNA |
300 | return found ? cur : NULL; |
301 | } | |
302 | EXPORT_SYMBOL_GPL(nf_ct_helper_expectfn_find_by_symbol); | |
303 | ||
b20ab9cc PNA |
304 | __printf(3, 4) |
305 | void nf_ct_helper_log(struct sk_buff *skb, const struct nf_conn *ct, | |
306 | const char *fmt, ...) | |
307 | { | |
308 | const struct nf_conn_help *help; | |
309 | const struct nf_conntrack_helper *helper; | |
f9caed59 JP |
310 | struct va_format vaf; |
311 | va_list args; | |
312 | ||
313 | va_start(args, fmt); | |
314 | ||
315 | vaf.fmt = fmt; | |
316 | vaf.va = &args; | |
b20ab9cc PNA |
317 | |
318 | /* Called from the helper function, this call never fails */ | |
319 | help = nfct_help(ct); | |
320 | ||
e2361cb9 | 321 | /* rcu_read_lock()ed by nf_hook_thresh */ |
b20ab9cc PNA |
322 | helper = rcu_dereference(help->helper); |
323 | ||
30e0c6a6 | 324 | nf_log_packet(nf_ct_net(ct), nf_ct_l3num(ct), 0, skb, NULL, NULL, NULL, |
f9caed59 JP |
325 | "nf_ct_%s: dropping packet: %pV ", helper->name, &vaf); |
326 | ||
327 | va_end(args); | |
b20ab9cc PNA |
328 | } |
329 | EXPORT_SYMBOL_GPL(nf_ct_helper_log); | |
330 | ||
7e5d03bb MJ |
331 | int nf_conntrack_helper_register(struct nf_conntrack_helper *me) |
332 | { | |
893e093c | 333 | struct nf_conntrack_tuple_mask mask = { .src.u.all = htons(0xFFFF) }; |
b8a7fe6c | 334 | unsigned int h = helper_hash(&me->tuple); |
893e093c | 335 | struct nf_conntrack_helper *cur; |
66e5a6b1 | 336 | int ret = 0, i; |
b8a7fe6c | 337 | |
6002f266 PM |
338 | BUG_ON(me->expect_policy == NULL); |
339 | BUG_ON(me->expect_class_max >= NF_CT_MAX_EXPECT_CLASSES); | |
af9d32ad | 340 | BUG_ON(strlen(me->name) > NF_CT_HELPER_NAME_LEN - 1); |
7e5d03bb | 341 | |
92f73221 GF |
342 | if (me->expect_policy->max_expected > NF_CT_EXPECT_MAX_CNT) |
343 | return -EINVAL; | |
344 | ||
58a3c9bb | 345 | mutex_lock(&nf_ct_helper_mutex); |
66e5a6b1 LZ |
346 | for (i = 0; i < nf_ct_helper_hsize; i++) { |
347 | hlist_for_each_entry(cur, &nf_ct_helper_hash[i], hnode) { | |
348 | if (!strcmp(cur->name, me->name) && | |
349 | (cur->tuple.src.l3num == NFPROTO_UNSPEC || | |
350 | cur->tuple.src.l3num == me->tuple.src.l3num) && | |
351 | cur->tuple.dst.protonum == me->tuple.dst.protonum) { | |
352 | ret = -EEXIST; | |
353 | goto out; | |
354 | } | |
355 | } | |
356 | } | |
357 | ||
358 | /* avoid unpredictable behaviour for auto_assign_helper */ | |
359 | if (!(me->flags & NF_CT_HELPER_F_USERSPACE)) { | |
360 | hlist_for_each_entry(cur, &nf_ct_helper_hash[h], hnode) { | |
361 | if (nf_ct_tuple_src_mask_cmp(&cur->tuple, &me->tuple, | |
362 | &mask)) { | |
363 | ret = -EEXIST; | |
364 | goto out; | |
365 | } | |
12f7a505 PNA |
366 | } |
367 | } | |
9338d7b4 | 368 | refcount_set(&me->refcnt, 1); |
58a3c9bb | 369 | hlist_add_head_rcu(&me->hnode, &nf_ct_helper_hash[h]); |
b8a7fe6c | 370 | nf_ct_helper_count++; |
12f7a505 | 371 | out: |
58a3c9bb | 372 | mutex_unlock(&nf_ct_helper_mutex); |
12f7a505 | 373 | return ret; |
7e5d03bb | 374 | } |
13b18339 | 375 | EXPORT_SYMBOL_GPL(nf_conntrack_helper_register); |
7e5d03bb | 376 | |
ac7b8483 | 377 | static bool expect_iter_me(struct nf_conntrack_expect *exp, void *data) |
7e5d03bb | 378 | { |
ac7b8483 FW |
379 | struct nf_conn_help *help = nfct_help(exp->master); |
380 | const struct nf_conntrack_helper *me = data; | |
381 | const struct nf_conntrack_helper *this; | |
382 | ||
383 | if (exp->helper == me) | |
384 | return true; | |
436a850d | 385 | |
ac7b8483 FW |
386 | this = rcu_dereference_protected(help->helper, |
387 | lockdep_is_held(&nf_conntrack_expect_lock)); | |
388 | return this == me; | |
389 | } | |
390 | ||
391 | void nf_conntrack_helper_unregister(struct nf_conntrack_helper *me) | |
392 | { | |
436a850d FW |
393 | mutex_lock(&nf_ct_helper_mutex); |
394 | hlist_del_rcu(&me->hnode); | |
395 | nf_ct_helper_count--; | |
396 | mutex_unlock(&nf_ct_helper_mutex); | |
397 | ||
398 | /* Make sure every nothing is still using the helper unless its a | |
399 | * connection in the hash. | |
400 | */ | |
401 | synchronize_rcu(); | |
7e5d03bb | 402 | |
ac7b8483 | 403 | nf_ct_expect_iterate_destroy(expect_iter_me, NULL); |
ff1acc49 | 404 | nf_ct_iterate_destroy(unhelp, me); |
ad9852af GF |
405 | |
406 | /* Maybe someone has gotten the helper already when unhelp above. | |
407 | * So need to wait it. | |
408 | */ | |
409 | synchronize_rcu(); | |
68047937 | 410 | } |
13b18339 | 411 | EXPORT_SYMBOL_GPL(nf_conntrack_helper_unregister); |
ceceae1b | 412 | |
82de0be6 GF |
413 | void nf_ct_helper_init(struct nf_conntrack_helper *helper, |
414 | u16 l3num, u16 protonum, const char *name, | |
415 | u16 default_port, u16 spec_port, u32 id, | |
416 | const struct nf_conntrack_expect_policy *exp_pol, | |
9f0f3ebe | 417 | u32 expect_class_max, |
82de0be6 GF |
418 | int (*help)(struct sk_buff *skb, unsigned int protoff, |
419 | struct nf_conn *ct, | |
420 | enum ip_conntrack_info ctinfo), | |
421 | int (*from_nlattr)(struct nlattr *attr, | |
422 | struct nf_conn *ct), | |
423 | struct module *module) | |
424 | { | |
425 | helper->tuple.src.l3num = l3num; | |
426 | helper->tuple.dst.protonum = protonum; | |
427 | helper->tuple.src.u.all = htons(spec_port); | |
428 | helper->expect_policy = exp_pol; | |
429 | helper->expect_class_max = expect_class_max; | |
82de0be6 GF |
430 | helper->help = help; |
431 | helper->from_nlattr = from_nlattr; | |
432 | helper->me = module; | |
433 | ||
434 | if (spec_port == default_port) | |
435 | snprintf(helper->name, sizeof(helper->name), "%s", name); | |
436 | else | |
437 | snprintf(helper->name, sizeof(helper->name), "%s-%u", name, id); | |
438 | } | |
439 | EXPORT_SYMBOL_GPL(nf_ct_helper_init); | |
440 | ||
441 | int nf_conntrack_helpers_register(struct nf_conntrack_helper *helper, | |
442 | unsigned int n) | |
443 | { | |
444 | unsigned int i; | |
445 | int err = 0; | |
446 | ||
447 | for (i = 0; i < n; i++) { | |
448 | err = nf_conntrack_helper_register(&helper[i]); | |
449 | if (err < 0) | |
450 | goto err; | |
451 | } | |
452 | ||
453 | return err; | |
454 | err: | |
455 | if (i > 0) | |
456 | nf_conntrack_helpers_unregister(helper, i); | |
457 | return err; | |
458 | } | |
459 | EXPORT_SYMBOL_GPL(nf_conntrack_helpers_register); | |
460 | ||
461 | void nf_conntrack_helpers_unregister(struct nf_conntrack_helper *helper, | |
462 | unsigned int n) | |
463 | { | |
464 | while (n-- > 0) | |
465 | nf_conntrack_helper_unregister(&helper[n]); | |
466 | } | |
467 | EXPORT_SYMBOL_GPL(nf_conntrack_helpers_unregister); | |
468 | ||
23f671a1 | 469 | static const struct nf_ct_ext_type helper_extend = { |
ceceae1b YK |
470 | .len = sizeof(struct nf_conn_help), |
471 | .align = __alignof__(struct nf_conn_help), | |
472 | .id = NF_CT_EXT_HELPER, | |
473 | }; | |
474 | ||
fc3893fd | 475 | void nf_conntrack_helper_pernet_init(struct net *net) |
ceceae1b | 476 | { |
a9006892 EL |
477 | net->ct.auto_assign_helper_warned = false; |
478 | net->ct.sysctl_auto_assign_helper = nf_ct_auto_assign_helper; | |
5e615b22 | 479 | } |
a9006892 | 480 | |
5e615b22 G |
481 | int nf_conntrack_helper_init(void) |
482 | { | |
483 | int ret; | |
484 | nf_ct_helper_hsize = 1; /* gets rounded up to use one page */ | |
485 | nf_ct_helper_hash = | |
486 | nf_ct_alloc_hashtable(&nf_ct_helper_hsize, 0); | |
487 | if (!nf_ct_helper_hash) | |
488 | return -ENOMEM; | |
489 | ||
490 | ret = nf_ct_extend_register(&helper_extend); | |
491 | if (ret < 0) { | |
492 | pr_err("nf_ct_helper: Unable to register helper extension.\n"); | |
493 | goto out_extend; | |
a9006892 EL |
494 | } |
495 | ||
b8a7fe6c | 496 | return 0; |
5e615b22 | 497 | out_extend: |
285189c7 | 498 | kvfree(nf_ct_helper_hash); |
5e615b22 | 499 | return ret; |
ceceae1b YK |
500 | } |
501 | ||
5e615b22 | 502 | void nf_conntrack_helper_fini(void) |
ceceae1b | 503 | { |
5e615b22 | 504 | nf_ct_extend_unregister(&helper_extend); |
285189c7 | 505 | kvfree(nf_ct_helper_hash); |
ceceae1b | 506 | } |