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Commit | Line | Data |
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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 MJ |
26 | #include <net/netfilter/nf_conntrack.h> |
27 | #include <net/netfilter/nf_conntrack_l3proto.h> | |
605dcad6 | 28 | #include <net/netfilter/nf_conntrack_l4proto.h> |
7e5d03bb MJ |
29 | #include <net/netfilter/nf_conntrack_helper.h> |
30 | #include <net/netfilter/nf_conntrack_core.h> | |
ceceae1b | 31 | #include <net/netfilter/nf_conntrack_extend.h> |
b20ab9cc | 32 | #include <net/netfilter/nf_log.h> |
7e5d03bb | 33 | |
58a3c9bb | 34 | static DEFINE_MUTEX(nf_ct_helper_mutex); |
12f7a505 PNA |
35 | struct hlist_head *nf_ct_helper_hash __read_mostly; |
36 | EXPORT_SYMBOL_GPL(nf_ct_helper_hash); | |
37 | unsigned int nf_ct_helper_hsize __read_mostly; | |
38 | EXPORT_SYMBOL_GPL(nf_ct_helper_hsize); | |
b8a7fe6c | 39 | static unsigned int nf_ct_helper_count __read_mostly; |
b8a7fe6c | 40 | |
3bb398d9 | 41 | static bool nf_ct_auto_assign_helper __read_mostly = false; |
a9006892 EL |
42 | module_param_named(nf_conntrack_helper, nf_ct_auto_assign_helper, bool, 0644); |
43 | MODULE_PARM_DESC(nf_conntrack_helper, | |
3bb398d9 | 44 | "Enable automatic conntrack helper assignment (default 0)"); |
a9006892 EL |
45 | |
46 | #ifdef CONFIG_SYSCTL | |
47 | static struct ctl_table helper_sysctl_table[] = { | |
48 | { | |
49 | .procname = "nf_conntrack_helper", | |
50 | .data = &init_net.ct.sysctl_auto_assign_helper, | |
51 | .maxlen = sizeof(unsigned int), | |
52 | .mode = 0644, | |
53 | .proc_handler = proc_dointvec, | |
54 | }, | |
55 | {} | |
56 | }; | |
57 | ||
58 | static int nf_conntrack_helper_init_sysctl(struct net *net) | |
59 | { | |
60 | struct ctl_table *table; | |
61 | ||
62 | table = kmemdup(helper_sysctl_table, sizeof(helper_sysctl_table), | |
63 | GFP_KERNEL); | |
64 | if (!table) | |
65 | goto out; | |
66 | ||
67 | table[0].data = &net->ct.sysctl_auto_assign_helper; | |
68 | ||
464dc801 EB |
69 | /* Don't export sysctls to unprivileged users */ |
70 | if (net->user_ns != &init_user_ns) | |
71 | table[0].procname = NULL; | |
72 | ||
a9006892 EL |
73 | net->ct.helper_sysctl_header = |
74 | register_net_sysctl(net, "net/netfilter", table); | |
75 | ||
76 | if (!net->ct.helper_sysctl_header) { | |
77 | pr_err("nf_conntrack_helper: can't register to sysctl.\n"); | |
78 | goto out_register; | |
79 | } | |
80 | return 0; | |
81 | ||
82 | out_register: | |
83 | kfree(table); | |
84 | out: | |
85 | return -ENOMEM; | |
86 | } | |
87 | ||
88 | static void nf_conntrack_helper_fini_sysctl(struct net *net) | |
89 | { | |
90 | struct ctl_table *table; | |
91 | ||
92 | table = net->ct.helper_sysctl_header->ctl_table_arg; | |
93 | unregister_net_sysctl_table(net->ct.helper_sysctl_header); | |
94 | kfree(table); | |
95 | } | |
96 | #else | |
97 | static int nf_conntrack_helper_init_sysctl(struct net *net) | |
98 | { | |
99 | return 0; | |
100 | } | |
101 | ||
102 | static void nf_conntrack_helper_fini_sysctl(struct net *net) | |
103 | { | |
104 | } | |
105 | #endif /* CONFIG_SYSCTL */ | |
b8a7fe6c PM |
106 | |
107 | /* Stupid hash, but collision free for the default registrations of the | |
108 | * helpers currently in the kernel. */ | |
109 | static unsigned int helper_hash(const struct nf_conntrack_tuple *tuple) | |
110 | { | |
111 | return (((tuple->src.l3num << 8) | tuple->dst.protonum) ^ | |
a34c4589 | 112 | (__force __u16)tuple->src.u.all) % nf_ct_helper_hsize; |
b8a7fe6c | 113 | } |
7e5d03bb | 114 | |
226c0c0e | 115 | static struct nf_conntrack_helper * |
7e5d03bb MJ |
116 | __nf_ct_helper_find(const struct nf_conntrack_tuple *tuple) |
117 | { | |
b8a7fe6c | 118 | struct nf_conntrack_helper *helper; |
d4156e8c | 119 | struct nf_conntrack_tuple_mask mask = { .src.u.all = htons(0xFFFF) }; |
b8a7fe6c | 120 | unsigned int h; |
7e5d03bb | 121 | |
b8a7fe6c PM |
122 | if (!nf_ct_helper_count) |
123 | return NULL; | |
124 | ||
125 | h = helper_hash(tuple); | |
b67bfe0d | 126 | hlist_for_each_entry_rcu(helper, &nf_ct_helper_hash[h], hnode) { |
b8a7fe6c PM |
127 | if (nf_ct_tuple_src_mask_cmp(tuple, &helper->tuple, &mask)) |
128 | return helper; | |
7e5d03bb MJ |
129 | } |
130 | return NULL; | |
131 | } | |
7e5d03bb MJ |
132 | |
133 | struct nf_conntrack_helper * | |
794e6871 | 134 | __nf_conntrack_helper_find(const char *name, u16 l3num, u8 protonum) |
7e5d03bb MJ |
135 | { |
136 | struct nf_conntrack_helper *h; | |
b8a7fe6c | 137 | unsigned int i; |
7e5d03bb | 138 | |
b8a7fe6c | 139 | for (i = 0; i < nf_ct_helper_hsize; i++) { |
b67bfe0d | 140 | hlist_for_each_entry_rcu(h, &nf_ct_helper_hash[i], hnode) { |
6114cc51 FW |
141 | if (strcmp(h->name, name)) |
142 | continue; | |
143 | ||
144 | if (h->tuple.src.l3num != NFPROTO_UNSPEC && | |
145 | h->tuple.src.l3num != l3num) | |
146 | continue; | |
147 | ||
148 | if (h->tuple.dst.protonum == protonum) | |
b8a7fe6c PM |
149 | return h; |
150 | } | |
7e5d03bb | 151 | } |
7e5d03bb MJ |
152 | return NULL; |
153 | } | |
794e6871 | 154 | EXPORT_SYMBOL_GPL(__nf_conntrack_helper_find); |
7e5d03bb | 155 | |
84f3bb9a PM |
156 | struct nf_conntrack_helper * |
157 | nf_conntrack_helper_try_module_get(const char *name, u16 l3num, u8 protonum) | |
158 | { | |
159 | struct nf_conntrack_helper *h; | |
160 | ||
8b5995d0 GF |
161 | rcu_read_lock(); |
162 | ||
84f3bb9a PM |
163 | h = __nf_conntrack_helper_find(name, l3num, protonum); |
164 | #ifdef CONFIG_MODULES | |
165 | if (h == NULL) { | |
8b5995d0 GF |
166 | rcu_read_unlock(); |
167 | if (request_module("nfct-helper-%s", name) == 0) { | |
168 | rcu_read_lock(); | |
84f3bb9a | 169 | h = __nf_conntrack_helper_find(name, l3num, protonum); |
8b5995d0 GF |
170 | } else { |
171 | return h; | |
172 | } | |
84f3bb9a PM |
173 | } |
174 | #endif | |
175 | if (h != NULL && !try_module_get(h->me)) | |
176 | h = NULL; | |
177 | ||
8b5995d0 GF |
178 | rcu_read_unlock(); |
179 | ||
84f3bb9a PM |
180 | return h; |
181 | } | |
182 | EXPORT_SYMBOL_GPL(nf_conntrack_helper_try_module_get); | |
183 | ||
1afc5679 PNA |
184 | struct nf_conn_help * |
185 | nf_ct_helper_ext_add(struct nf_conn *ct, | |
186 | struct nf_conntrack_helper *helper, gfp_t gfp) | |
b560580a PM |
187 | { |
188 | struct nf_conn_help *help; | |
189 | ||
1afc5679 PNA |
190 | help = nf_ct_ext_add_length(ct, NF_CT_EXT_HELPER, |
191 | helper->data_len, gfp); | |
b560580a PM |
192 | if (help) |
193 | INIT_HLIST_HEAD(&help->expectations); | |
194 | else | |
195 | pr_debug("failed to add helper extension area"); | |
196 | return help; | |
197 | } | |
198 | EXPORT_SYMBOL_GPL(nf_ct_helper_ext_add); | |
199 | ||
dfe75ff8 JK |
200 | static struct nf_conntrack_helper * |
201 | nf_ct_lookup_helper(struct nf_conn *ct, struct net *net) | |
202 | { | |
203 | if (!net->ct.sysctl_auto_assign_helper) { | |
204 | if (net->ct.auto_assign_helper_warned) | |
205 | return NULL; | |
206 | if (!__nf_ct_helper_find(&ct->tuplehash[IP_CT_DIR_REPLY].tuple)) | |
207 | return NULL; | |
208 | pr_info("nf_conntrack: default automatic helper assignment " | |
209 | "has been turned off for security reasons and CT-based " | |
210 | " firewall rule not found. Use the iptables CT target " | |
211 | "to attach helpers instead.\n"); | |
212 | net->ct.auto_assign_helper_warned = 1; | |
213 | return NULL; | |
214 | } | |
215 | ||
216 | return __nf_ct_helper_find(&ct->tuplehash[IP_CT_DIR_REPLY].tuple); | |
217 | } | |
218 | ||
219 | ||
b2a15a60 PM |
220 | int __nf_ct_try_assign_helper(struct nf_conn *ct, struct nf_conn *tmpl, |
221 | gfp_t flags) | |
226c0c0e | 222 | { |
b2a15a60 PM |
223 | struct nf_conntrack_helper *helper = NULL; |
224 | struct nf_conn_help *help; | |
a9006892 | 225 | struct net *net = nf_ct_net(ct); |
226c0c0e | 226 | |
6714cf54 PNA |
227 | /* We already got a helper explicitly attached. The function |
228 | * nf_conntrack_alter_reply - in case NAT is in use - asks for looking | |
229 | * the helper up again. Since now the user is in full control of | |
230 | * making consistent helper configurations, skip this automatic | |
231 | * re-lookup, otherwise we'll lose the helper. | |
232 | */ | |
233 | if (test_bit(IPS_HELPER_BIT, &ct->status)) | |
234 | return 0; | |
235 | ||
b2a15a60 PM |
236 | if (tmpl != NULL) { |
237 | help = nfct_help(tmpl); | |
6714cf54 | 238 | if (help != NULL) { |
b2a15a60 | 239 | helper = help->helper; |
6714cf54 PNA |
240 | set_bit(IPS_HELPER_BIT, &ct->status); |
241 | } | |
b2a15a60 PM |
242 | } |
243 | ||
244 | help = nfct_help(ct); | |
a9006892 | 245 | |
226c0c0e | 246 | if (helper == NULL) { |
dfe75ff8 JK |
247 | helper = nf_ct_lookup_helper(ct, net); |
248 | if (helper == NULL) { | |
249 | if (help) | |
250 | RCU_INIT_POINTER(help->helper, NULL); | |
251 | return 0; | |
252 | } | |
226c0c0e PNA |
253 | } |
254 | ||
255 | if (help == NULL) { | |
1afc5679 | 256 | help = nf_ct_helper_ext_add(ct, helper, flags); |
cf71c03e PN |
257 | if (help == NULL) |
258 | return -ENOMEM; | |
226c0c0e | 259 | } else { |
32f53760 PNA |
260 | /* We only allow helper re-assignment of the same sort since |
261 | * we cannot reallocate the helper extension area. | |
262 | */ | |
6e2f0aa8 FW |
263 | struct nf_conntrack_helper *tmp = rcu_dereference(help->helper); |
264 | ||
265 | if (tmp && tmp->help != helper->help) { | |
32f53760 | 266 | RCU_INIT_POINTER(help->helper, NULL); |
cf71c03e | 267 | return 0; |
32f53760 | 268 | } |
226c0c0e PNA |
269 | } |
270 | ||
cf778b00 | 271 | rcu_assign_pointer(help->helper, helper); |
cf71c03e PN |
272 | |
273 | return 0; | |
226c0c0e PNA |
274 | } |
275 | EXPORT_SYMBOL_GPL(__nf_ct_try_assign_helper); | |
276 | ||
01cfa0a4 | 277 | /* appropriate ct lock protecting must be taken by caller */ |
7e5d03bb MJ |
278 | static inline int unhelp(struct nf_conntrack_tuple_hash *i, |
279 | const struct nf_conntrack_helper *me) | |
280 | { | |
281 | struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(i); | |
282 | struct nf_conn_help *help = nfct_help(ct); | |
283 | ||
ca7433df | 284 | if (help && rcu_dereference_raw(help->helper) == me) { |
7e5d03bb | 285 | nf_conntrack_event(IPCT_HELPER, ct); |
a9b3cd7f | 286 | RCU_INIT_POINTER(help->helper, NULL); |
7e5d03bb MJ |
287 | } |
288 | return 0; | |
289 | } | |
290 | ||
9858a3ae PNA |
291 | void nf_ct_helper_destroy(struct nf_conn *ct) |
292 | { | |
293 | struct nf_conn_help *help = nfct_help(ct); | |
294 | struct nf_conntrack_helper *helper; | |
295 | ||
296 | if (help) { | |
297 | rcu_read_lock(); | |
298 | helper = rcu_dereference(help->helper); | |
299 | if (helper && helper->destroy) | |
300 | helper->destroy(ct); | |
301 | rcu_read_unlock(); | |
302 | } | |
303 | } | |
304 | ||
544d5c7d PNA |
305 | static LIST_HEAD(nf_ct_helper_expectfn_list); |
306 | ||
307 | void nf_ct_helper_expectfn_register(struct nf_ct_helper_expectfn *n) | |
308 | { | |
ca7433df | 309 | spin_lock_bh(&nf_conntrack_expect_lock); |
544d5c7d | 310 | list_add_rcu(&n->head, &nf_ct_helper_expectfn_list); |
ca7433df | 311 | spin_unlock_bh(&nf_conntrack_expect_lock); |
544d5c7d PNA |
312 | } |
313 | EXPORT_SYMBOL_GPL(nf_ct_helper_expectfn_register); | |
314 | ||
315 | void nf_ct_helper_expectfn_unregister(struct nf_ct_helper_expectfn *n) | |
316 | { | |
ca7433df | 317 | spin_lock_bh(&nf_conntrack_expect_lock); |
544d5c7d | 318 | list_del_rcu(&n->head); |
ca7433df | 319 | spin_unlock_bh(&nf_conntrack_expect_lock); |
544d5c7d PNA |
320 | } |
321 | EXPORT_SYMBOL_GPL(nf_ct_helper_expectfn_unregister); | |
322 | ||
8b5995d0 | 323 | /* Caller should hold the rcu lock */ |
544d5c7d PNA |
324 | struct nf_ct_helper_expectfn * |
325 | nf_ct_helper_expectfn_find_by_name(const char *name) | |
326 | { | |
327 | struct nf_ct_helper_expectfn *cur; | |
328 | bool found = false; | |
329 | ||
544d5c7d PNA |
330 | list_for_each_entry_rcu(cur, &nf_ct_helper_expectfn_list, head) { |
331 | if (!strcmp(cur->name, name)) { | |
332 | found = true; | |
333 | break; | |
334 | } | |
335 | } | |
544d5c7d PNA |
336 | return found ? cur : NULL; |
337 | } | |
338 | EXPORT_SYMBOL_GPL(nf_ct_helper_expectfn_find_by_name); | |
339 | ||
8b5995d0 | 340 | /* Caller should hold the rcu lock */ |
544d5c7d PNA |
341 | struct nf_ct_helper_expectfn * |
342 | nf_ct_helper_expectfn_find_by_symbol(const void *symbol) | |
343 | { | |
344 | struct nf_ct_helper_expectfn *cur; | |
345 | bool found = false; | |
346 | ||
544d5c7d PNA |
347 | list_for_each_entry_rcu(cur, &nf_ct_helper_expectfn_list, head) { |
348 | if (cur->expectfn == symbol) { | |
349 | found = true; | |
350 | break; | |
351 | } | |
352 | } | |
544d5c7d PNA |
353 | return found ? cur : NULL; |
354 | } | |
355 | EXPORT_SYMBOL_GPL(nf_ct_helper_expectfn_find_by_symbol); | |
356 | ||
b20ab9cc PNA |
357 | __printf(3, 4) |
358 | void nf_ct_helper_log(struct sk_buff *skb, const struct nf_conn *ct, | |
359 | const char *fmt, ...) | |
360 | { | |
361 | const struct nf_conn_help *help; | |
362 | const struct nf_conntrack_helper *helper; | |
f9caed59 JP |
363 | struct va_format vaf; |
364 | va_list args; | |
365 | ||
366 | va_start(args, fmt); | |
367 | ||
368 | vaf.fmt = fmt; | |
369 | vaf.va = &args; | |
b20ab9cc PNA |
370 | |
371 | /* Called from the helper function, this call never fails */ | |
372 | help = nfct_help(ct); | |
373 | ||
e2361cb9 | 374 | /* rcu_read_lock()ed by nf_hook_thresh */ |
b20ab9cc PNA |
375 | helper = rcu_dereference(help->helper); |
376 | ||
30e0c6a6 | 377 | nf_log_packet(nf_ct_net(ct), nf_ct_l3num(ct), 0, skb, NULL, NULL, NULL, |
f9caed59 JP |
378 | "nf_ct_%s: dropping packet: %pV ", helper->name, &vaf); |
379 | ||
380 | va_end(args); | |
b20ab9cc PNA |
381 | } |
382 | EXPORT_SYMBOL_GPL(nf_ct_helper_log); | |
383 | ||
7e5d03bb MJ |
384 | int nf_conntrack_helper_register(struct nf_conntrack_helper *me) |
385 | { | |
893e093c | 386 | struct nf_conntrack_tuple_mask mask = { .src.u.all = htons(0xFFFF) }; |
b8a7fe6c | 387 | unsigned int h = helper_hash(&me->tuple); |
893e093c PNA |
388 | struct nf_conntrack_helper *cur; |
389 | int ret = 0; | |
b8a7fe6c | 390 | |
6002f266 PM |
391 | BUG_ON(me->expect_policy == NULL); |
392 | BUG_ON(me->expect_class_max >= NF_CT_MAX_EXPECT_CLASSES); | |
af9d32ad | 393 | BUG_ON(strlen(me->name) > NF_CT_HELPER_NAME_LEN - 1); |
7e5d03bb | 394 | |
58a3c9bb | 395 | mutex_lock(&nf_ct_helper_mutex); |
b67bfe0d | 396 | hlist_for_each_entry(cur, &nf_ct_helper_hash[h], hnode) { |
893e093c | 397 | if (nf_ct_tuple_src_mask_cmp(&cur->tuple, &me->tuple, &mask)) { |
12f7a505 PNA |
398 | ret = -EEXIST; |
399 | goto out; | |
400 | } | |
401 | } | |
58a3c9bb | 402 | hlist_add_head_rcu(&me->hnode, &nf_ct_helper_hash[h]); |
b8a7fe6c | 403 | nf_ct_helper_count++; |
12f7a505 | 404 | out: |
58a3c9bb | 405 | mutex_unlock(&nf_ct_helper_mutex); |
12f7a505 | 406 | return ret; |
7e5d03bb | 407 | } |
13b18339 | 408 | EXPORT_SYMBOL_GPL(nf_conntrack_helper_register); |
7e5d03bb | 409 | |
68047937 AD |
410 | static void __nf_conntrack_helper_unregister(struct nf_conntrack_helper *me, |
411 | struct net *net) | |
436a850d FW |
412 | { |
413 | struct nf_conntrack_tuple_hash *h; | |
414 | const struct hlist_nulls_node *nn; | |
415 | int cpu; | |
416 | ||
417 | /* Get rid of expecteds, set helpers to NULL. */ | |
418 | for_each_possible_cpu(cpu) { | |
419 | struct ct_pcpu *pcpu = per_cpu_ptr(net->ct.pcpu_lists, cpu); | |
420 | ||
421 | spin_lock_bh(&pcpu->lock); | |
422 | hlist_nulls_for_each_entry(h, nn, &pcpu->unconfirmed, hnnode) | |
423 | unhelp(h, me); | |
424 | spin_unlock_bh(&pcpu->lock); | |
425 | } | |
426 | } | |
427 | ||
428 | void nf_conntrack_helper_unregister(struct nf_conntrack_helper *me) | |
7e5d03bb | 429 | { |
7e5d03bb | 430 | struct nf_conntrack_tuple_hash *h; |
31f15875 | 431 | struct nf_conntrack_expect *exp; |
b67bfe0d | 432 | const struct hlist_node *next; |
ea781f19 | 433 | const struct hlist_nulls_node *nn; |
8786a971 LZ |
434 | unsigned int last_hsize; |
435 | spinlock_t *lock; | |
436a850d | 436 | struct net *net; |
31f15875 | 437 | unsigned int i; |
436a850d FW |
438 | |
439 | mutex_lock(&nf_ct_helper_mutex); | |
440 | hlist_del_rcu(&me->hnode); | |
441 | nf_ct_helper_count--; | |
442 | mutex_unlock(&nf_ct_helper_mutex); | |
443 | ||
444 | /* Make sure every nothing is still using the helper unless its a | |
445 | * connection in the hash. | |
446 | */ | |
447 | synchronize_rcu(); | |
7e5d03bb | 448 | |
7e5d03bb | 449 | /* Get rid of expectations */ |
ca7433df | 450 | spin_lock_bh(&nf_conntrack_expect_lock); |
31f15875 | 451 | for (i = 0; i < nf_ct_expect_hsize; i++) { |
b67bfe0d | 452 | hlist_for_each_entry_safe(exp, next, |
0a93aaed | 453 | &nf_ct_expect_hash[i], hnode) { |
31f15875 | 454 | struct nf_conn_help *help = nfct_help(exp->master); |
c5d277d2 ED |
455 | if ((rcu_dereference_protected( |
456 | help->helper, | |
ca7433df | 457 | lockdep_is_held(&nf_conntrack_expect_lock) |
c5d277d2 | 458 | ) == me || exp->helper == me) && |
31f15875 PM |
459 | del_timer(&exp->timeout)) { |
460 | nf_ct_unlink_expect(exp); | |
461 | nf_ct_expect_put(exp); | |
462 | } | |
7e5d03bb MJ |
463 | } |
464 | } | |
ca7433df | 465 | spin_unlock_bh(&nf_conntrack_expect_lock); |
7e5d03bb | 466 | |
436a850d FW |
467 | rtnl_lock(); |
468 | for_each_net(net) | |
469 | __nf_conntrack_helper_unregister(me, net); | |
470 | rtnl_unlock(); | |
b7779d06 | 471 | |
93bb0ceb | 472 | local_bh_disable(); |
8786a971 LZ |
473 | restart: |
474 | last_hsize = nf_conntrack_htable_size; | |
475 | for (i = 0; i < last_hsize; i++) { | |
476 | lock = &nf_conntrack_locks[i % CONNTRACK_LOCKS]; | |
477 | nf_conntrack_lock(lock); | |
478 | if (last_hsize != nf_conntrack_htable_size) { | |
479 | spin_unlock(lock); | |
480 | goto restart; | |
93bb0ceb | 481 | } |
8786a971 LZ |
482 | hlist_nulls_for_each_entry(h, nn, &nf_conntrack_hash[i], hnnode) |
483 | unhelp(h, me); | |
484 | spin_unlock(lock); | |
7e5d03bb | 485 | } |
93bb0ceb | 486 | local_bh_enable(); |
68047937 | 487 | } |
13b18339 | 488 | EXPORT_SYMBOL_GPL(nf_conntrack_helper_unregister); |
ceceae1b | 489 | |
82de0be6 GF |
490 | void nf_ct_helper_init(struct nf_conntrack_helper *helper, |
491 | u16 l3num, u16 protonum, const char *name, | |
492 | u16 default_port, u16 spec_port, u32 id, | |
493 | const struct nf_conntrack_expect_policy *exp_pol, | |
494 | u32 expect_class_max, u32 data_len, | |
495 | int (*help)(struct sk_buff *skb, unsigned int protoff, | |
496 | struct nf_conn *ct, | |
497 | enum ip_conntrack_info ctinfo), | |
498 | int (*from_nlattr)(struct nlattr *attr, | |
499 | struct nf_conn *ct), | |
500 | struct module *module) | |
501 | { | |
502 | helper->tuple.src.l3num = l3num; | |
503 | helper->tuple.dst.protonum = protonum; | |
504 | helper->tuple.src.u.all = htons(spec_port); | |
505 | helper->expect_policy = exp_pol; | |
506 | helper->expect_class_max = expect_class_max; | |
507 | helper->data_len = data_len; | |
508 | helper->help = help; | |
509 | helper->from_nlattr = from_nlattr; | |
510 | helper->me = module; | |
511 | ||
512 | if (spec_port == default_port) | |
513 | snprintf(helper->name, sizeof(helper->name), "%s", name); | |
514 | else | |
515 | snprintf(helper->name, sizeof(helper->name), "%s-%u", name, id); | |
516 | } | |
517 | EXPORT_SYMBOL_GPL(nf_ct_helper_init); | |
518 | ||
519 | int nf_conntrack_helpers_register(struct nf_conntrack_helper *helper, | |
520 | unsigned int n) | |
521 | { | |
522 | unsigned int i; | |
523 | int err = 0; | |
524 | ||
525 | for (i = 0; i < n; i++) { | |
526 | err = nf_conntrack_helper_register(&helper[i]); | |
527 | if (err < 0) | |
528 | goto err; | |
529 | } | |
530 | ||
531 | return err; | |
532 | err: | |
533 | if (i > 0) | |
534 | nf_conntrack_helpers_unregister(helper, i); | |
535 | return err; | |
536 | } | |
537 | EXPORT_SYMBOL_GPL(nf_conntrack_helpers_register); | |
538 | ||
539 | void nf_conntrack_helpers_unregister(struct nf_conntrack_helper *helper, | |
540 | unsigned int n) | |
541 | { | |
542 | while (n-- > 0) | |
543 | nf_conntrack_helper_unregister(&helper[n]); | |
544 | } | |
545 | EXPORT_SYMBOL_GPL(nf_conntrack_helpers_unregister); | |
546 | ||
61eb3107 | 547 | static struct nf_ct_ext_type helper_extend __read_mostly = { |
ceceae1b YK |
548 | .len = sizeof(struct nf_conn_help), |
549 | .align = __alignof__(struct nf_conn_help), | |
550 | .id = NF_CT_EXT_HELPER, | |
551 | }; | |
552 | ||
5e615b22 | 553 | int nf_conntrack_helper_pernet_init(struct net *net) |
ceceae1b | 554 | { |
a9006892 EL |
555 | net->ct.auto_assign_helper_warned = false; |
556 | net->ct.sysctl_auto_assign_helper = nf_ct_auto_assign_helper; | |
5e615b22 G |
557 | return nf_conntrack_helper_init_sysctl(net); |
558 | } | |
b8a7fe6c | 559 | |
5e615b22 G |
560 | void nf_conntrack_helper_pernet_fini(struct net *net) |
561 | { | |
562 | nf_conntrack_helper_fini_sysctl(net); | |
563 | } | |
a9006892 | 564 | |
5e615b22 G |
565 | int nf_conntrack_helper_init(void) |
566 | { | |
567 | int ret; | |
568 | nf_ct_helper_hsize = 1; /* gets rounded up to use one page */ | |
569 | nf_ct_helper_hash = | |
570 | nf_ct_alloc_hashtable(&nf_ct_helper_hsize, 0); | |
571 | if (!nf_ct_helper_hash) | |
572 | return -ENOMEM; | |
573 | ||
574 | ret = nf_ct_extend_register(&helper_extend); | |
575 | if (ret < 0) { | |
576 | pr_err("nf_ct_helper: Unable to register helper extension.\n"); | |
577 | goto out_extend; | |
a9006892 EL |
578 | } |
579 | ||
b8a7fe6c | 580 | return 0; |
5e615b22 | 581 | out_extend: |
d862a662 | 582 | nf_ct_free_hashtable(nf_ct_helper_hash, nf_ct_helper_hsize); |
5e615b22 | 583 | return ret; |
ceceae1b YK |
584 | } |
585 | ||
5e615b22 | 586 | void nf_conntrack_helper_fini(void) |
ceceae1b | 587 | { |
5e615b22 G |
588 | nf_ct_extend_unregister(&helper_extend); |
589 | nf_ct_free_hashtable(nf_ct_helper_hash, nf_ct_helper_hsize); | |
ceceae1b | 590 | } |