netfilter: get rid of atomic ops in fast path
[linux-2.6-block.git] / net / netfilter / x_tables.c
CommitLineData
2e4e6a17
HW
1/*
2 * x_tables core - Backend for {ip,ip6,arp}_tables
3 *
4 * Copyright (C) 2006-2006 Harald Welte <laforge@netfilter.org>
5 *
6 * Based on existing ip_tables code which is
7 * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
8 * Copyright (C) 2000-2005 Netfilter Core Team <coreteam@netfilter.org>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13 *
14 */
be91fd5e 15#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
2e4e6a17
HW
16#include <linux/kernel.h>
17#include <linux/socket.h>
18#include <linux/net.h>
19#include <linux/proc_fs.h>
20#include <linux/seq_file.h>
21#include <linux/string.h>
22#include <linux/vmalloc.h>
9e19bb6d 23#include <linux/mutex.h>
d7fe0f24 24#include <linux/mm.h>
5a0e3ad6 25#include <linux/slab.h>
fbabf31e 26#include <linux/audit.h>
457c4cbc 27#include <net/net_namespace.h>
2e4e6a17
HW
28
29#include <linux/netfilter/x_tables.h>
30#include <linux/netfilter_arp.h>
e3eaa991
JE
31#include <linux/netfilter_ipv4/ip_tables.h>
32#include <linux/netfilter_ipv6/ip6_tables.h>
33#include <linux/netfilter_arp/arp_tables.h>
9e19bb6d 34
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HW
35MODULE_LICENSE("GPL");
36MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
043ef46c 37MODULE_DESCRIPTION("{ip,ip6,arp,eb}_tables backend module");
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HW
38
39#define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1))
40
b386d9f5 41struct compat_delta {
255d0dc3
ED
42 unsigned int offset; /* offset in kernel */
43 int delta; /* delta in 32bit user land */
b386d9f5
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44};
45
2e4e6a17 46struct xt_af {
9e19bb6d 47 struct mutex mutex;
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HW
48 struct list_head match;
49 struct list_head target;
b386d9f5 50#ifdef CONFIG_COMPAT
2722971c 51 struct mutex compat_mutex;
255d0dc3
ED
52 struct compat_delta *compat_tab;
53 unsigned int number; /* number of slots in compat_tab[] */
54 unsigned int cur; /* number of used slots in compat_tab[] */
b386d9f5 55#endif
2e4e6a17
HW
56};
57
58static struct xt_af *xt;
59
7e9c6eeb
JE
60static const char *const xt_prefix[NFPROTO_NUMPROTO] = {
61 [NFPROTO_UNSPEC] = "x",
62 [NFPROTO_IPV4] = "ip",
63 [NFPROTO_ARP] = "arp",
64 [NFPROTO_BRIDGE] = "eb",
65 [NFPROTO_IPV6] = "ip6",
37f9f733
PM
66};
67
f3c5c1bf
JE
68/* Allow this many total (re)entries. */
69static const unsigned int xt_jumpstack_multiplier = 2;
70
2e4e6a17
HW
71/* Registration hooks for targets. */
72int
a45049c5 73xt_register_target(struct xt_target *target)
2e4e6a17 74{
76108cea
JE
75 u_int8_t af = target->family;
76 int ret;
2e4e6a17 77
9e19bb6d 78 ret = mutex_lock_interruptible(&xt[af].mutex);
2e4e6a17
HW
79 if (ret != 0)
80 return ret;
81 list_add(&target->list, &xt[af].target);
9e19bb6d 82 mutex_unlock(&xt[af].mutex);
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HW
83 return ret;
84}
85EXPORT_SYMBOL(xt_register_target);
86
87void
a45049c5 88xt_unregister_target(struct xt_target *target)
2e4e6a17 89{
76108cea 90 u_int8_t af = target->family;
a45049c5 91
9e19bb6d 92 mutex_lock(&xt[af].mutex);
df0933dc 93 list_del(&target->list);
9e19bb6d 94 mutex_unlock(&xt[af].mutex);
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HW
95}
96EXPORT_SYMBOL(xt_unregister_target);
97
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98int
99xt_register_targets(struct xt_target *target, unsigned int n)
100{
101 unsigned int i;
102 int err = 0;
103
104 for (i = 0; i < n; i++) {
105 err = xt_register_target(&target[i]);
106 if (err)
107 goto err;
108 }
109 return err;
110
111err:
112 if (i > 0)
113 xt_unregister_targets(target, i);
114 return err;
115}
116EXPORT_SYMBOL(xt_register_targets);
117
118void
119xt_unregister_targets(struct xt_target *target, unsigned int n)
120{
f68c5301
CG
121 while (n-- > 0)
122 xt_unregister_target(&target[n]);
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123}
124EXPORT_SYMBOL(xt_unregister_targets);
125
2e4e6a17 126int
a45049c5 127xt_register_match(struct xt_match *match)
2e4e6a17 128{
76108cea
JE
129 u_int8_t af = match->family;
130 int ret;
2e4e6a17 131
9e19bb6d 132 ret = mutex_lock_interruptible(&xt[af].mutex);
2e4e6a17
HW
133 if (ret != 0)
134 return ret;
135
136 list_add(&match->list, &xt[af].match);
9e19bb6d 137 mutex_unlock(&xt[af].mutex);
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HW
138
139 return ret;
140}
141EXPORT_SYMBOL(xt_register_match);
142
143void
a45049c5 144xt_unregister_match(struct xt_match *match)
2e4e6a17 145{
76108cea 146 u_int8_t af = match->family;
a45049c5 147
9e19bb6d 148 mutex_lock(&xt[af].mutex);
df0933dc 149 list_del(&match->list);
9e19bb6d 150 mutex_unlock(&xt[af].mutex);
2e4e6a17
HW
151}
152EXPORT_SYMBOL(xt_unregister_match);
153
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154int
155xt_register_matches(struct xt_match *match, unsigned int n)
156{
157 unsigned int i;
158 int err = 0;
159
160 for (i = 0; i < n; i++) {
161 err = xt_register_match(&match[i]);
162 if (err)
163 goto err;
164 }
165 return err;
166
167err:
168 if (i > 0)
169 xt_unregister_matches(match, i);
170 return err;
171}
172EXPORT_SYMBOL(xt_register_matches);
173
174void
175xt_unregister_matches(struct xt_match *match, unsigned int n)
176{
f68c5301
CG
177 while (n-- > 0)
178 xt_unregister_match(&match[n]);
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PM
179}
180EXPORT_SYMBOL(xt_unregister_matches);
181
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HW
182
183/*
184 * These are weird, but module loading must not be done with mutex
185 * held (since they will register), and we have to have a single
adb00ae2 186 * function to use.
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HW
187 */
188
189/* Find match, grabs ref. Returns ERR_PTR() on error. */
76108cea 190struct xt_match *xt_find_match(u8 af, const char *name, u8 revision)
2e4e6a17
HW
191{
192 struct xt_match *m;
42046e2e 193 int err = -ENOENT;
2e4e6a17 194
9e19bb6d 195 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
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HW
196 return ERR_PTR(-EINTR);
197
198 list_for_each_entry(m, &xt[af].match, list) {
199 if (strcmp(m->name, name) == 0) {
200 if (m->revision == revision) {
201 if (try_module_get(m->me)) {
9e19bb6d 202 mutex_unlock(&xt[af].mutex);
2e4e6a17
HW
203 return m;
204 }
205 } else
206 err = -EPROTOTYPE; /* Found something. */
207 }
208 }
9e19bb6d 209 mutex_unlock(&xt[af].mutex);
55b69e91
JE
210
211 if (af != NFPROTO_UNSPEC)
212 /* Try searching again in the family-independent list */
213 return xt_find_match(NFPROTO_UNSPEC, name, revision);
214
2e4e6a17
HW
215 return ERR_PTR(err);
216}
217EXPORT_SYMBOL(xt_find_match);
218
fd0ec0e6
JE
219struct xt_match *
220xt_request_find_match(uint8_t nfproto, const char *name, uint8_t revision)
221{
222 struct xt_match *match;
223
adb00ae2
SH
224 match = xt_find_match(nfproto, name, revision);
225 if (IS_ERR(match)) {
226 request_module("%st_%s", xt_prefix[nfproto], name);
227 match = xt_find_match(nfproto, name, revision);
228 }
229
230 return match;
fd0ec0e6
JE
231}
232EXPORT_SYMBOL_GPL(xt_request_find_match);
233
2e4e6a17 234/* Find target, grabs ref. Returns ERR_PTR() on error. */
76108cea 235struct xt_target *xt_find_target(u8 af, const char *name, u8 revision)
2e4e6a17
HW
236{
237 struct xt_target *t;
42046e2e 238 int err = -ENOENT;
2e4e6a17 239
9e19bb6d 240 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
2e4e6a17
HW
241 return ERR_PTR(-EINTR);
242
243 list_for_each_entry(t, &xt[af].target, list) {
244 if (strcmp(t->name, name) == 0) {
245 if (t->revision == revision) {
246 if (try_module_get(t->me)) {
9e19bb6d 247 mutex_unlock(&xt[af].mutex);
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HW
248 return t;
249 }
250 } else
251 err = -EPROTOTYPE; /* Found something. */
252 }
253 }
9e19bb6d 254 mutex_unlock(&xt[af].mutex);
55b69e91
JE
255
256 if (af != NFPROTO_UNSPEC)
257 /* Try searching again in the family-independent list */
258 return xt_find_target(NFPROTO_UNSPEC, name, revision);
259
2e4e6a17
HW
260 return ERR_PTR(err);
261}
262EXPORT_SYMBOL(xt_find_target);
263
76108cea 264struct xt_target *xt_request_find_target(u8 af, const char *name, u8 revision)
2e4e6a17
HW
265{
266 struct xt_target *target;
267
adb00ae2
SH
268 target = xt_find_target(af, name, revision);
269 if (IS_ERR(target)) {
270 request_module("%st_%s", xt_prefix[af], name);
271 target = xt_find_target(af, name, revision);
272 }
273
274 return target;
2e4e6a17
HW
275}
276EXPORT_SYMBOL_GPL(xt_request_find_target);
277
76108cea 278static int match_revfn(u8 af, const char *name, u8 revision, int *bestp)
2e4e6a17 279{
5452e425 280 const struct xt_match *m;
2e4e6a17
HW
281 int have_rev = 0;
282
283 list_for_each_entry(m, &xt[af].match, list) {
284 if (strcmp(m->name, name) == 0) {
285 if (m->revision > *bestp)
286 *bestp = m->revision;
287 if (m->revision == revision)
288 have_rev = 1;
289 }
290 }
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291
292 if (af != NFPROTO_UNSPEC && !have_rev)
293 return match_revfn(NFPROTO_UNSPEC, name, revision, bestp);
294
2e4e6a17
HW
295 return have_rev;
296}
297
76108cea 298static int target_revfn(u8 af, const char *name, u8 revision, int *bestp)
2e4e6a17 299{
5452e425 300 const struct xt_target *t;
2e4e6a17
HW
301 int have_rev = 0;
302
303 list_for_each_entry(t, &xt[af].target, list) {
304 if (strcmp(t->name, name) == 0) {
305 if (t->revision > *bestp)
306 *bestp = t->revision;
307 if (t->revision == revision)
308 have_rev = 1;
309 }
310 }
656caff2
PM
311
312 if (af != NFPROTO_UNSPEC && !have_rev)
313 return target_revfn(NFPROTO_UNSPEC, name, revision, bestp);
314
2e4e6a17
HW
315 return have_rev;
316}
317
318/* Returns true or false (if no such extension at all) */
76108cea 319int xt_find_revision(u8 af, const char *name, u8 revision, int target,
2e4e6a17
HW
320 int *err)
321{
322 int have_rev, best = -1;
323
9e19bb6d 324 if (mutex_lock_interruptible(&xt[af].mutex) != 0) {
2e4e6a17
HW
325 *err = -EINTR;
326 return 1;
327 }
328 if (target == 1)
329 have_rev = target_revfn(af, name, revision, &best);
330 else
331 have_rev = match_revfn(af, name, revision, &best);
9e19bb6d 332 mutex_unlock(&xt[af].mutex);
2e4e6a17
HW
333
334 /* Nothing at all? Return 0 to try loading module. */
335 if (best == -1) {
336 *err = -ENOENT;
337 return 0;
338 }
339
340 *err = best;
341 if (!have_rev)
342 *err = -EPROTONOSUPPORT;
343 return 1;
344}
345EXPORT_SYMBOL_GPL(xt_find_revision);
346
45185364
JE
347static char *textify_hooks(char *buf, size_t size, unsigned int mask)
348{
349 static const char *const names[] = {
350 "PREROUTING", "INPUT", "FORWARD",
351 "OUTPUT", "POSTROUTING", "BROUTING",
352 };
353 unsigned int i;
354 char *p = buf;
355 bool np = false;
356 int res;
357
358 *p = '\0';
359 for (i = 0; i < ARRAY_SIZE(names); ++i) {
360 if (!(mask & (1 << i)))
361 continue;
362 res = snprintf(p, size, "%s%s", np ? "/" : "", names[i]);
363 if (res > 0) {
364 size -= res;
365 p += res;
366 }
367 np = true;
368 }
369
370 return buf;
371}
372
916a917d 373int xt_check_match(struct xt_mtchk_param *par,
9b4fce7a 374 unsigned int size, u_int8_t proto, bool inv_proto)
37f9f733 375{
bd414ee6
JE
376 int ret;
377
9b4fce7a
JE
378 if (XT_ALIGN(par->match->matchsize) != size &&
379 par->match->matchsize != -1) {
043ef46c
JE
380 /*
381 * ebt_among is exempt from centralized matchsize checking
382 * because it uses a dynamic-size data set.
383 */
b402405d
JE
384 pr_err("%s_tables: %s.%u match: invalid size "
385 "%u (kernel) != (user) %u\n",
916a917d 386 xt_prefix[par->family], par->match->name,
b402405d 387 par->match->revision,
9b4fce7a 388 XT_ALIGN(par->match->matchsize), size);
37f9f733
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389 return -EINVAL;
390 }
9b4fce7a
JE
391 if (par->match->table != NULL &&
392 strcmp(par->match->table, par->table) != 0) {
3dd5d7e3 393 pr_err("%s_tables: %s match: only valid in %s table, not %s\n",
916a917d 394 xt_prefix[par->family], par->match->name,
9b4fce7a 395 par->match->table, par->table);
37f9f733
PM
396 return -EINVAL;
397 }
9b4fce7a 398 if (par->match->hooks && (par->hook_mask & ~par->match->hooks) != 0) {
45185364
JE
399 char used[64], allow[64];
400
3dd5d7e3 401 pr_err("%s_tables: %s match: used from hooks %s, but only "
45185364 402 "valid from %s\n",
916a917d 403 xt_prefix[par->family], par->match->name,
45185364
JE
404 textify_hooks(used, sizeof(used), par->hook_mask),
405 textify_hooks(allow, sizeof(allow), par->match->hooks));
37f9f733
PM
406 return -EINVAL;
407 }
9b4fce7a 408 if (par->match->proto && (par->match->proto != proto || inv_proto)) {
3dd5d7e3 409 pr_err("%s_tables: %s match: only valid for protocol %u\n",
916a917d
JE
410 xt_prefix[par->family], par->match->name,
411 par->match->proto);
37f9f733
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412 return -EINVAL;
413 }
bd414ee6
JE
414 if (par->match->checkentry != NULL) {
415 ret = par->match->checkentry(par);
416 if (ret < 0)
417 return ret;
418 else if (ret > 0)
419 /* Flag up potential errors. */
420 return -EIO;
421 }
37f9f733
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422 return 0;
423}
424EXPORT_SYMBOL_GPL(xt_check_match);
425
2722971c 426#ifdef CONFIG_COMPAT
255d0dc3 427int xt_compat_add_offset(u_int8_t af, unsigned int offset, int delta)
b386d9f5 428{
255d0dc3 429 struct xt_af *xp = &xt[af];
b386d9f5 430
255d0dc3
ED
431 if (!xp->compat_tab) {
432 if (!xp->number)
433 return -EINVAL;
434 xp->compat_tab = vmalloc(sizeof(struct compat_delta) * xp->number);
435 if (!xp->compat_tab)
436 return -ENOMEM;
437 xp->cur = 0;
438 }
b386d9f5 439
255d0dc3
ED
440 if (xp->cur >= xp->number)
441 return -EINVAL;
b386d9f5 442
255d0dc3
ED
443 if (xp->cur)
444 delta += xp->compat_tab[xp->cur - 1].delta;
445 xp->compat_tab[xp->cur].offset = offset;
446 xp->compat_tab[xp->cur].delta = delta;
447 xp->cur++;
b386d9f5
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448 return 0;
449}
450EXPORT_SYMBOL_GPL(xt_compat_add_offset);
451
76108cea 452void xt_compat_flush_offsets(u_int8_t af)
b386d9f5 453{
255d0dc3
ED
454 if (xt[af].compat_tab) {
455 vfree(xt[af].compat_tab);
456 xt[af].compat_tab = NULL;
457 xt[af].number = 0;
b386d9f5
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458 }
459}
460EXPORT_SYMBOL_GPL(xt_compat_flush_offsets);
461
3e5e524f 462int xt_compat_calc_jump(u_int8_t af, unsigned int offset)
b386d9f5 463{
255d0dc3
ED
464 struct compat_delta *tmp = xt[af].compat_tab;
465 int mid, left = 0, right = xt[af].cur - 1;
466
467 while (left <= right) {
468 mid = (left + right) >> 1;
469 if (offset > tmp[mid].offset)
470 left = mid + 1;
471 else if (offset < tmp[mid].offset)
472 right = mid - 1;
473 else
474 return mid ? tmp[mid - 1].delta : 0;
475 }
476 WARN_ON_ONCE(1);
477 return 0;
b386d9f5
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478}
479EXPORT_SYMBOL_GPL(xt_compat_calc_jump);
480
255d0dc3
ED
481void xt_compat_init_offsets(u_int8_t af, unsigned int number)
482{
483 xt[af].number = number;
484 xt[af].cur = 0;
485}
486EXPORT_SYMBOL(xt_compat_init_offsets);
487
5452e425 488int xt_compat_match_offset(const struct xt_match *match)
2722971c 489{
9fa492cd
PM
490 u_int16_t csize = match->compatsize ? : match->matchsize;
491 return XT_ALIGN(match->matchsize) - COMPAT_XT_ALIGN(csize);
492}
493EXPORT_SYMBOL_GPL(xt_compat_match_offset);
494
89566951 495int xt_compat_match_from_user(struct xt_entry_match *m, void **dstptr,
b0a6363c 496 unsigned int *size)
9fa492cd 497{
5452e425 498 const struct xt_match *match = m->u.kernel.match;
9fa492cd
PM
499 struct compat_xt_entry_match *cm = (struct compat_xt_entry_match *)m;
500 int pad, off = xt_compat_match_offset(match);
501 u_int16_t msize = cm->u.user.match_size;
502
503 m = *dstptr;
504 memcpy(m, cm, sizeof(*cm));
505 if (match->compat_from_user)
506 match->compat_from_user(m->data, cm->data);
507 else
508 memcpy(m->data, cm->data, msize - sizeof(*cm));
509 pad = XT_ALIGN(match->matchsize) - match->matchsize;
510 if (pad > 0)
511 memset(m->data + match->matchsize, 0, pad);
512
513 msize += off;
514 m->u.user.match_size = msize;
515
516 *size += off;
517 *dstptr += msize;
89566951 518 return 0;
9fa492cd
PM
519}
520EXPORT_SYMBOL_GPL(xt_compat_match_from_user);
521
739674fb
JE
522int xt_compat_match_to_user(const struct xt_entry_match *m,
523 void __user **dstptr, unsigned int *size)
9fa492cd 524{
5452e425 525 const struct xt_match *match = m->u.kernel.match;
9fa492cd
PM
526 struct compat_xt_entry_match __user *cm = *dstptr;
527 int off = xt_compat_match_offset(match);
528 u_int16_t msize = m->u.user.match_size - off;
529
530 if (copy_to_user(cm, m, sizeof(*cm)) ||
a18aa31b
PM
531 put_user(msize, &cm->u.user.match_size) ||
532 copy_to_user(cm->u.user.name, m->u.kernel.match->name,
533 strlen(m->u.kernel.match->name) + 1))
601e68e1 534 return -EFAULT;
9fa492cd
PM
535
536 if (match->compat_to_user) {
537 if (match->compat_to_user((void __user *)cm->data, m->data))
538 return -EFAULT;
539 } else {
540 if (copy_to_user(cm->data, m->data, msize - sizeof(*cm)))
541 return -EFAULT;
2722971c 542 }
9fa492cd
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543
544 *size -= off;
545 *dstptr += msize;
546 return 0;
2722971c 547}
9fa492cd
PM
548EXPORT_SYMBOL_GPL(xt_compat_match_to_user);
549#endif /* CONFIG_COMPAT */
2722971c 550
916a917d 551int xt_check_target(struct xt_tgchk_param *par,
af5d6dc2 552 unsigned int size, u_int8_t proto, bool inv_proto)
37f9f733 553{
d6b00a53
JE
554 int ret;
555
af5d6dc2 556 if (XT_ALIGN(par->target->targetsize) != size) {
b402405d
JE
557 pr_err("%s_tables: %s.%u target: invalid size "
558 "%u (kernel) != (user) %u\n",
916a917d 559 xt_prefix[par->family], par->target->name,
b402405d 560 par->target->revision,
af5d6dc2 561 XT_ALIGN(par->target->targetsize), size);
37f9f733
PM
562 return -EINVAL;
563 }
af5d6dc2
JE
564 if (par->target->table != NULL &&
565 strcmp(par->target->table, par->table) != 0) {
3dd5d7e3 566 pr_err("%s_tables: %s target: only valid in %s table, not %s\n",
916a917d 567 xt_prefix[par->family], par->target->name,
af5d6dc2 568 par->target->table, par->table);
37f9f733
PM
569 return -EINVAL;
570 }
af5d6dc2 571 if (par->target->hooks && (par->hook_mask & ~par->target->hooks) != 0) {
45185364
JE
572 char used[64], allow[64];
573
3dd5d7e3 574 pr_err("%s_tables: %s target: used from hooks %s, but only "
45185364 575 "usable from %s\n",
916a917d 576 xt_prefix[par->family], par->target->name,
45185364
JE
577 textify_hooks(used, sizeof(used), par->hook_mask),
578 textify_hooks(allow, sizeof(allow), par->target->hooks));
37f9f733
PM
579 return -EINVAL;
580 }
af5d6dc2 581 if (par->target->proto && (par->target->proto != proto || inv_proto)) {
3dd5d7e3 582 pr_err("%s_tables: %s target: only valid for protocol %u\n",
916a917d 583 xt_prefix[par->family], par->target->name,
af5d6dc2 584 par->target->proto);
37f9f733
PM
585 return -EINVAL;
586 }
d6b00a53
JE
587 if (par->target->checkentry != NULL) {
588 ret = par->target->checkentry(par);
589 if (ret < 0)
590 return ret;
591 else if (ret > 0)
592 /* Flag up potential errors. */
593 return -EIO;
594 }
37f9f733
PM
595 return 0;
596}
597EXPORT_SYMBOL_GPL(xt_check_target);
598
2722971c 599#ifdef CONFIG_COMPAT
5452e425 600int xt_compat_target_offset(const struct xt_target *target)
2722971c 601{
9fa492cd
PM
602 u_int16_t csize = target->compatsize ? : target->targetsize;
603 return XT_ALIGN(target->targetsize) - COMPAT_XT_ALIGN(csize);
604}
605EXPORT_SYMBOL_GPL(xt_compat_target_offset);
606
607void xt_compat_target_from_user(struct xt_entry_target *t, void **dstptr,
b0a6363c 608 unsigned int *size)
9fa492cd 609{
5452e425 610 const struct xt_target *target = t->u.kernel.target;
9fa492cd
PM
611 struct compat_xt_entry_target *ct = (struct compat_xt_entry_target *)t;
612 int pad, off = xt_compat_target_offset(target);
613 u_int16_t tsize = ct->u.user.target_size;
614
615 t = *dstptr;
616 memcpy(t, ct, sizeof(*ct));
617 if (target->compat_from_user)
618 target->compat_from_user(t->data, ct->data);
619 else
620 memcpy(t->data, ct->data, tsize - sizeof(*ct));
621 pad = XT_ALIGN(target->targetsize) - target->targetsize;
622 if (pad > 0)
623 memset(t->data + target->targetsize, 0, pad);
624
625 tsize += off;
626 t->u.user.target_size = tsize;
627
628 *size += off;
629 *dstptr += tsize;
630}
631EXPORT_SYMBOL_GPL(xt_compat_target_from_user);
632
739674fb
JE
633int xt_compat_target_to_user(const struct xt_entry_target *t,
634 void __user **dstptr, unsigned int *size)
9fa492cd 635{
5452e425 636 const struct xt_target *target = t->u.kernel.target;
9fa492cd
PM
637 struct compat_xt_entry_target __user *ct = *dstptr;
638 int off = xt_compat_target_offset(target);
639 u_int16_t tsize = t->u.user.target_size - off;
640
641 if (copy_to_user(ct, t, sizeof(*ct)) ||
a18aa31b
PM
642 put_user(tsize, &ct->u.user.target_size) ||
643 copy_to_user(ct->u.user.name, t->u.kernel.target->name,
644 strlen(t->u.kernel.target->name) + 1))
601e68e1 645 return -EFAULT;
9fa492cd
PM
646
647 if (target->compat_to_user) {
648 if (target->compat_to_user((void __user *)ct->data, t->data))
649 return -EFAULT;
650 } else {
651 if (copy_to_user(ct->data, t->data, tsize - sizeof(*ct)))
652 return -EFAULT;
2722971c 653 }
9fa492cd
PM
654
655 *size -= off;
656 *dstptr += tsize;
657 return 0;
2722971c 658}
9fa492cd 659EXPORT_SYMBOL_GPL(xt_compat_target_to_user);
2722971c
DM
660#endif
661
2e4e6a17
HW
662struct xt_table_info *xt_alloc_table_info(unsigned int size)
663{
664 struct xt_table_info *newinfo;
665 int cpu;
666
667 /* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */
4481374c 668 if ((SMP_ALIGN(size) >> PAGE_SHIFT) + 2 > totalram_pages)
2e4e6a17
HW
669 return NULL;
670
259d4e41 671 newinfo = kzalloc(XT_TABLE_INFO_SZ, GFP_KERNEL);
2e4e6a17
HW
672 if (!newinfo)
673 return NULL;
674
675 newinfo->size = size;
676
6f912042 677 for_each_possible_cpu(cpu) {
2e4e6a17
HW
678 if (size <= PAGE_SIZE)
679 newinfo->entries[cpu] = kmalloc_node(size,
680 GFP_KERNEL,
681 cpu_to_node(cpu));
682 else
683 newinfo->entries[cpu] = vmalloc_node(size,
684 cpu_to_node(cpu));
685
686 if (newinfo->entries[cpu] == NULL) {
687 xt_free_table_info(newinfo);
688 return NULL;
689 }
690 }
691
692 return newinfo;
693}
694EXPORT_SYMBOL(xt_alloc_table_info);
695
696void xt_free_table_info(struct xt_table_info *info)
697{
698 int cpu;
699
6f912042 700 for_each_possible_cpu(cpu) {
2e4e6a17
HW
701 if (info->size <= PAGE_SIZE)
702 kfree(info->entries[cpu]);
703 else
704 vfree(info->entries[cpu]);
705 }
f3c5c1bf
JE
706
707 if (info->jumpstack != NULL) {
708 if (sizeof(void *) * info->stacksize > PAGE_SIZE) {
709 for_each_possible_cpu(cpu)
710 vfree(info->jumpstack[cpu]);
711 } else {
712 for_each_possible_cpu(cpu)
713 kfree(info->jumpstack[cpu]);
714 }
715 }
716
717 if (sizeof(void **) * nr_cpu_ids > PAGE_SIZE)
718 vfree(info->jumpstack);
719 else
720 kfree(info->jumpstack);
7489aec8
ED
721
722 free_percpu(info->stackptr);
f3c5c1bf 723
2e4e6a17
HW
724 kfree(info);
725}
726EXPORT_SYMBOL(xt_free_table_info);
727
728/* Find table by name, grabs mutex & ref. Returns ERR_PTR() on error. */
76108cea
JE
729struct xt_table *xt_find_table_lock(struct net *net, u_int8_t af,
730 const char *name)
2e4e6a17
HW
731{
732 struct xt_table *t;
733
9e19bb6d 734 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
2e4e6a17
HW
735 return ERR_PTR(-EINTR);
736
8d870052 737 list_for_each_entry(t, &net->xt.tables[af], list)
2e4e6a17
HW
738 if (strcmp(t->name, name) == 0 && try_module_get(t->me))
739 return t;
9e19bb6d 740 mutex_unlock(&xt[af].mutex);
2e4e6a17
HW
741 return NULL;
742}
743EXPORT_SYMBOL_GPL(xt_find_table_lock);
744
745void xt_table_unlock(struct xt_table *table)
746{
9e19bb6d 747 mutex_unlock(&xt[table->af].mutex);
2e4e6a17
HW
748}
749EXPORT_SYMBOL_GPL(xt_table_unlock);
750
2722971c 751#ifdef CONFIG_COMPAT
76108cea 752void xt_compat_lock(u_int8_t af)
2722971c
DM
753{
754 mutex_lock(&xt[af].compat_mutex);
755}
756EXPORT_SYMBOL_GPL(xt_compat_lock);
757
76108cea 758void xt_compat_unlock(u_int8_t af)
2722971c
DM
759{
760 mutex_unlock(&xt[af].compat_mutex);
761}
762EXPORT_SYMBOL_GPL(xt_compat_unlock);
763#endif
2e4e6a17 764
7f5c6d4f
ED
765DEFINE_PER_CPU(seqcount_t, xt_recseq);
766EXPORT_PER_CPU_SYMBOL_GPL(xt_recseq);
942e4a2b 767
f3c5c1bf
JE
768static int xt_jumpstack_alloc(struct xt_table_info *i)
769{
770 unsigned int size;
771 int cpu;
772
7489aec8 773 i->stackptr = alloc_percpu(unsigned int);
f3c5c1bf
JE
774 if (i->stackptr == NULL)
775 return -ENOMEM;
f3c5c1bf
JE
776
777 size = sizeof(void **) * nr_cpu_ids;
778 if (size > PAGE_SIZE)
779 i->jumpstack = vmalloc(size);
780 else
781 i->jumpstack = kmalloc(size, GFP_KERNEL);
782 if (i->jumpstack == NULL)
783 return -ENOMEM;
784 memset(i->jumpstack, 0, size);
785
786 i->stacksize *= xt_jumpstack_multiplier;
787 size = sizeof(void *) * i->stacksize;
788 for_each_possible_cpu(cpu) {
789 if (size > PAGE_SIZE)
790 i->jumpstack[cpu] = vmalloc_node(size,
791 cpu_to_node(cpu));
792 else
793 i->jumpstack[cpu] = kmalloc_node(size,
794 GFP_KERNEL, cpu_to_node(cpu));
795 if (i->jumpstack[cpu] == NULL)
796 /*
797 * Freeing will be done later on by the callers. The
798 * chain is: xt_replace_table -> __do_replace ->
799 * do_replace -> xt_free_table_info.
800 */
801 return -ENOMEM;
802 }
803
804 return 0;
805}
942e4a2b 806
2e4e6a17
HW
807struct xt_table_info *
808xt_replace_table(struct xt_table *table,
809 unsigned int num_counters,
810 struct xt_table_info *newinfo,
811 int *error)
812{
942e4a2b 813 struct xt_table_info *private;
f3c5c1bf 814 int ret;
2e4e6a17 815
d97a9e47
JE
816 ret = xt_jumpstack_alloc(newinfo);
817 if (ret < 0) {
818 *error = ret;
819 return NULL;
820 }
821
2e4e6a17 822 /* Do the substitution. */
942e4a2b 823 local_bh_disable();
2e4e6a17 824 private = table->private;
942e4a2b 825
2e4e6a17
HW
826 /* Check inside lock: is the old number correct? */
827 if (num_counters != private->number) {
be91fd5e 828 pr_debug("num_counters != table->private->number (%u/%u)\n",
2e4e6a17 829 num_counters, private->number);
942e4a2b 830 local_bh_enable();
2e4e6a17
HW
831 *error = -EAGAIN;
832 return NULL;
833 }
2e4e6a17 834
942e4a2b
SH
835 table->private = newinfo;
836 newinfo->initial_entries = private->initial_entries;
837
838 /*
839 * Even though table entries have now been swapped, other CPU's
840 * may still be using the old entries. This is okay, because
841 * resynchronization happens because of the locking done
842 * during the get_counters() routine.
843 */
844 local_bh_enable();
845
fbabf31e
TG
846#ifdef CONFIG_AUDIT
847 if (audit_enabled) {
848 struct audit_buffer *ab;
849
850 ab = audit_log_start(current->audit_context, GFP_KERNEL,
851 AUDIT_NETFILTER_CFG);
852 if (ab) {
853 audit_log_format(ab, "table=%s family=%u entries=%u",
854 table->name, table->af,
855 private->number);
856 audit_log_end(ab);
857 }
858 }
859#endif
860
942e4a2b 861 return private;
2e4e6a17
HW
862}
863EXPORT_SYMBOL_GPL(xt_replace_table);
864
35aad0ff
JE
865struct xt_table *xt_register_table(struct net *net,
866 const struct xt_table *input_table,
a98da11d
AD
867 struct xt_table_info *bootstrap,
868 struct xt_table_info *newinfo)
2e4e6a17
HW
869{
870 int ret;
871 struct xt_table_info *private;
35aad0ff 872 struct xt_table *t, *table;
2e4e6a17 873
44d34e72 874 /* Don't add one object to multiple lists. */
35aad0ff 875 table = kmemdup(input_table, sizeof(struct xt_table), GFP_KERNEL);
44d34e72
AD
876 if (!table) {
877 ret = -ENOMEM;
878 goto out;
879 }
880
9e19bb6d 881 ret = mutex_lock_interruptible(&xt[table->af].mutex);
2e4e6a17 882 if (ret != 0)
44d34e72 883 goto out_free;
2e4e6a17
HW
884
885 /* Don't autoload: we'd eat our tail... */
8d870052 886 list_for_each_entry(t, &net->xt.tables[table->af], list) {
df0933dc
PM
887 if (strcmp(t->name, table->name) == 0) {
888 ret = -EEXIST;
889 goto unlock;
890 }
2e4e6a17
HW
891 }
892
893 /* Simplifies replace_table code. */
894 table->private = bootstrap;
78454473 895
2e4e6a17
HW
896 if (!xt_replace_table(table, 0, newinfo, &ret))
897 goto unlock;
898
899 private = table->private;
be91fd5e 900 pr_debug("table->private->number = %u\n", private->number);
2e4e6a17
HW
901
902 /* save number of initial entries */
903 private->initial_entries = private->number;
904
8d870052 905 list_add(&table->list, &net->xt.tables[table->af]);
a98da11d
AD
906 mutex_unlock(&xt[table->af].mutex);
907 return table;
2e4e6a17 908
2e4e6a17 909 unlock:
9e19bb6d 910 mutex_unlock(&xt[table->af].mutex);
44d34e72
AD
911out_free:
912 kfree(table);
a98da11d
AD
913out:
914 return ERR_PTR(ret);
2e4e6a17
HW
915}
916EXPORT_SYMBOL_GPL(xt_register_table);
917
918void *xt_unregister_table(struct xt_table *table)
919{
920 struct xt_table_info *private;
921
9e19bb6d 922 mutex_lock(&xt[table->af].mutex);
2e4e6a17 923 private = table->private;
df0933dc 924 list_del(&table->list);
9e19bb6d 925 mutex_unlock(&xt[table->af].mutex);
44d34e72 926 kfree(table);
2e4e6a17
HW
927
928 return private;
929}
930EXPORT_SYMBOL_GPL(xt_unregister_table);
931
932#ifdef CONFIG_PROC_FS
715cf35a
AD
933struct xt_names_priv {
934 struct seq_net_private p;
76108cea 935 u_int8_t af;
715cf35a 936};
025d93d1 937static void *xt_table_seq_start(struct seq_file *seq, loff_t *pos)
2e4e6a17 938{
715cf35a 939 struct xt_names_priv *priv = seq->private;
1218854a 940 struct net *net = seq_file_net(seq);
76108cea 941 u_int8_t af = priv->af;
2e4e6a17 942
025d93d1 943 mutex_lock(&xt[af].mutex);
715cf35a 944 return seq_list_start(&net->xt.tables[af], *pos);
025d93d1 945}
2e4e6a17 946
025d93d1
AD
947static void *xt_table_seq_next(struct seq_file *seq, void *v, loff_t *pos)
948{
715cf35a 949 struct xt_names_priv *priv = seq->private;
1218854a 950 struct net *net = seq_file_net(seq);
76108cea 951 u_int8_t af = priv->af;
2e4e6a17 952
715cf35a 953 return seq_list_next(v, &net->xt.tables[af], pos);
2e4e6a17
HW
954}
955
025d93d1 956static void xt_table_seq_stop(struct seq_file *seq, void *v)
2e4e6a17 957{
715cf35a 958 struct xt_names_priv *priv = seq->private;
76108cea 959 u_int8_t af = priv->af;
2e4e6a17 960
025d93d1
AD
961 mutex_unlock(&xt[af].mutex);
962}
2e4e6a17 963
025d93d1
AD
964static int xt_table_seq_show(struct seq_file *seq, void *v)
965{
966 struct xt_table *table = list_entry(v, struct xt_table, list);
2e4e6a17 967
025d93d1
AD
968 if (strlen(table->name))
969 return seq_printf(seq, "%s\n", table->name);
970 else
971 return 0;
972}
601e68e1 973
025d93d1
AD
974static const struct seq_operations xt_table_seq_ops = {
975 .start = xt_table_seq_start,
976 .next = xt_table_seq_next,
977 .stop = xt_table_seq_stop,
978 .show = xt_table_seq_show,
979};
980
981static int xt_table_open(struct inode *inode, struct file *file)
982{
983 int ret;
715cf35a 984 struct xt_names_priv *priv;
025d93d1 985
715cf35a
AD
986 ret = seq_open_net(inode, file, &xt_table_seq_ops,
987 sizeof(struct xt_names_priv));
025d93d1 988 if (!ret) {
715cf35a
AD
989 priv = ((struct seq_file *)file->private_data)->private;
990 priv->af = (unsigned long)PDE(inode)->data;
025d93d1
AD
991 }
992 return ret;
2e4e6a17
HW
993}
994
025d93d1
AD
995static const struct file_operations xt_table_ops = {
996 .owner = THIS_MODULE,
997 .open = xt_table_open,
998 .read = seq_read,
999 .llseek = seq_lseek,
0e93bb94 1000 .release = seq_release_net,
025d93d1
AD
1001};
1002
eb132205
JE
1003/*
1004 * Traverse state for ip{,6}_{tables,matches} for helping crossing
1005 * the multi-AF mutexes.
1006 */
1007struct nf_mttg_trav {
1008 struct list_head *head, *curr;
1009 uint8_t class, nfproto;
1010};
1011
1012enum {
1013 MTTG_TRAV_INIT,
1014 MTTG_TRAV_NFP_UNSPEC,
1015 MTTG_TRAV_NFP_SPEC,
1016 MTTG_TRAV_DONE,
1017};
1018
1019static void *xt_mttg_seq_next(struct seq_file *seq, void *v, loff_t *ppos,
1020 bool is_target)
2e4e6a17 1021{
eb132205
JE
1022 static const uint8_t next_class[] = {
1023 [MTTG_TRAV_NFP_UNSPEC] = MTTG_TRAV_NFP_SPEC,
1024 [MTTG_TRAV_NFP_SPEC] = MTTG_TRAV_DONE,
1025 };
1026 struct nf_mttg_trav *trav = seq->private;
1027
1028 switch (trav->class) {
1029 case MTTG_TRAV_INIT:
1030 trav->class = MTTG_TRAV_NFP_UNSPEC;
1031 mutex_lock(&xt[NFPROTO_UNSPEC].mutex);
1032 trav->head = trav->curr = is_target ?
1033 &xt[NFPROTO_UNSPEC].target : &xt[NFPROTO_UNSPEC].match;
1034 break;
1035 case MTTG_TRAV_NFP_UNSPEC:
1036 trav->curr = trav->curr->next;
1037 if (trav->curr != trav->head)
1038 break;
1039 mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
1040 mutex_lock(&xt[trav->nfproto].mutex);
1041 trav->head = trav->curr = is_target ?
1042 &xt[trav->nfproto].target : &xt[trav->nfproto].match;
1043 trav->class = next_class[trav->class];
1044 break;
1045 case MTTG_TRAV_NFP_SPEC:
1046 trav->curr = trav->curr->next;
1047 if (trav->curr != trav->head)
1048 break;
1049 /* fallthru, _stop will unlock */
1050 default:
1051 return NULL;
1052 }
2e4e6a17 1053
eb132205
JE
1054 if (ppos != NULL)
1055 ++*ppos;
1056 return trav;
025d93d1 1057}
601e68e1 1058
eb132205
JE
1059static void *xt_mttg_seq_start(struct seq_file *seq, loff_t *pos,
1060 bool is_target)
025d93d1 1061{
eb132205
JE
1062 struct nf_mttg_trav *trav = seq->private;
1063 unsigned int j;
2e4e6a17 1064
eb132205
JE
1065 trav->class = MTTG_TRAV_INIT;
1066 for (j = 0; j < *pos; ++j)
1067 if (xt_mttg_seq_next(seq, NULL, NULL, is_target) == NULL)
1068 return NULL;
1069 return trav;
2e4e6a17
HW
1070}
1071
eb132205 1072static void xt_mttg_seq_stop(struct seq_file *seq, void *v)
2e4e6a17 1073{
eb132205
JE
1074 struct nf_mttg_trav *trav = seq->private;
1075
1076 switch (trav->class) {
1077 case MTTG_TRAV_NFP_UNSPEC:
1078 mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
1079 break;
1080 case MTTG_TRAV_NFP_SPEC:
1081 mutex_unlock(&xt[trav->nfproto].mutex);
1082 break;
1083 }
1084}
2e4e6a17 1085
eb132205
JE
1086static void *xt_match_seq_start(struct seq_file *seq, loff_t *pos)
1087{
1088 return xt_mttg_seq_start(seq, pos, false);
2e4e6a17
HW
1089}
1090
eb132205 1091static void *xt_match_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
2e4e6a17 1092{
eb132205
JE
1093 return xt_mttg_seq_next(seq, v, ppos, false);
1094}
2e4e6a17 1095
eb132205
JE
1096static int xt_match_seq_show(struct seq_file *seq, void *v)
1097{
1098 const struct nf_mttg_trav *trav = seq->private;
1099 const struct xt_match *match;
1100
1101 switch (trav->class) {
1102 case MTTG_TRAV_NFP_UNSPEC:
1103 case MTTG_TRAV_NFP_SPEC:
1104 if (trav->curr == trav->head)
1105 return 0;
1106 match = list_entry(trav->curr, struct xt_match, list);
1107 return (*match->name == '\0') ? 0 :
1108 seq_printf(seq, "%s\n", match->name);
1109 }
1110 return 0;
2e4e6a17
HW
1111}
1112
025d93d1
AD
1113static const struct seq_operations xt_match_seq_ops = {
1114 .start = xt_match_seq_start,
1115 .next = xt_match_seq_next,
eb132205 1116 .stop = xt_mttg_seq_stop,
025d93d1 1117 .show = xt_match_seq_show,
2e4e6a17
HW
1118};
1119
025d93d1 1120static int xt_match_open(struct inode *inode, struct file *file)
2e4e6a17 1121{
eb132205
JE
1122 struct seq_file *seq;
1123 struct nf_mttg_trav *trav;
2e4e6a17
HW
1124 int ret;
1125
eb132205
JE
1126 trav = kmalloc(sizeof(*trav), GFP_KERNEL);
1127 if (trav == NULL)
1128 return -ENOMEM;
2e4e6a17 1129
eb132205
JE
1130 ret = seq_open(file, &xt_match_seq_ops);
1131 if (ret < 0) {
1132 kfree(trav);
1133 return ret;
2e4e6a17 1134 }
eb132205
JE
1135
1136 seq = file->private_data;
1137 seq->private = trav;
1138 trav->nfproto = (unsigned long)PDE(inode)->data;
1139 return 0;
025d93d1
AD
1140}
1141
1142static const struct file_operations xt_match_ops = {
1143 .owner = THIS_MODULE,
1144 .open = xt_match_open,
1145 .read = seq_read,
1146 .llseek = seq_lseek,
eb132205 1147 .release = seq_release_private,
025d93d1 1148};
2e4e6a17 1149
025d93d1
AD
1150static void *xt_target_seq_start(struct seq_file *seq, loff_t *pos)
1151{
eb132205 1152 return xt_mttg_seq_start(seq, pos, true);
025d93d1
AD
1153}
1154
eb132205 1155static void *xt_target_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
025d93d1 1156{
eb132205 1157 return xt_mttg_seq_next(seq, v, ppos, true);
025d93d1
AD
1158}
1159
1160static int xt_target_seq_show(struct seq_file *seq, void *v)
1161{
eb132205
JE
1162 const struct nf_mttg_trav *trav = seq->private;
1163 const struct xt_target *target;
1164
1165 switch (trav->class) {
1166 case MTTG_TRAV_NFP_UNSPEC:
1167 case MTTG_TRAV_NFP_SPEC:
1168 if (trav->curr == trav->head)
1169 return 0;
1170 target = list_entry(trav->curr, struct xt_target, list);
1171 return (*target->name == '\0') ? 0 :
1172 seq_printf(seq, "%s\n", target->name);
1173 }
1174 return 0;
025d93d1
AD
1175}
1176
1177static const struct seq_operations xt_target_seq_ops = {
1178 .start = xt_target_seq_start,
1179 .next = xt_target_seq_next,
eb132205 1180 .stop = xt_mttg_seq_stop,
025d93d1
AD
1181 .show = xt_target_seq_show,
1182};
1183
1184static int xt_target_open(struct inode *inode, struct file *file)
1185{
eb132205
JE
1186 struct seq_file *seq;
1187 struct nf_mttg_trav *trav;
025d93d1
AD
1188 int ret;
1189
eb132205
JE
1190 trav = kmalloc(sizeof(*trav), GFP_KERNEL);
1191 if (trav == NULL)
1192 return -ENOMEM;
025d93d1 1193
eb132205
JE
1194 ret = seq_open(file, &xt_target_seq_ops);
1195 if (ret < 0) {
1196 kfree(trav);
1197 return ret;
025d93d1 1198 }
eb132205
JE
1199
1200 seq = file->private_data;
1201 seq->private = trav;
1202 trav->nfproto = (unsigned long)PDE(inode)->data;
1203 return 0;
2e4e6a17
HW
1204}
1205
025d93d1 1206static const struct file_operations xt_target_ops = {
2e4e6a17 1207 .owner = THIS_MODULE,
025d93d1 1208 .open = xt_target_open,
2e4e6a17
HW
1209 .read = seq_read,
1210 .llseek = seq_lseek,
eb132205 1211 .release = seq_release_private,
2e4e6a17
HW
1212};
1213
1214#define FORMAT_TABLES "_tables_names"
1215#define FORMAT_MATCHES "_tables_matches"
1216#define FORMAT_TARGETS "_tables_targets"
1217
1218#endif /* CONFIG_PROC_FS */
1219
2b95efe7
JE
1220/**
1221 * xt_hook_link - set up hooks for a new table
1222 * @table: table with metadata needed to set up hooks
1223 * @fn: Hook function
1224 *
1225 * This function will take care of creating and registering the necessary
1226 * Netfilter hooks for XT tables.
1227 */
1228struct nf_hook_ops *xt_hook_link(const struct xt_table *table, nf_hookfn *fn)
1229{
1230 unsigned int hook_mask = table->valid_hooks;
1231 uint8_t i, num_hooks = hweight32(hook_mask);
1232 uint8_t hooknum;
1233 struct nf_hook_ops *ops;
1234 int ret;
1235
1236 ops = kmalloc(sizeof(*ops) * num_hooks, GFP_KERNEL);
1237 if (ops == NULL)
1238 return ERR_PTR(-ENOMEM);
1239
1240 for (i = 0, hooknum = 0; i < num_hooks && hook_mask != 0;
1241 hook_mask >>= 1, ++hooknum) {
1242 if (!(hook_mask & 1))
1243 continue;
1244 ops[i].hook = fn;
1245 ops[i].owner = table->me;
1246 ops[i].pf = table->af;
1247 ops[i].hooknum = hooknum;
1248 ops[i].priority = table->priority;
1249 ++i;
1250 }
1251
1252 ret = nf_register_hooks(ops, num_hooks);
1253 if (ret < 0) {
1254 kfree(ops);
1255 return ERR_PTR(ret);
1256 }
1257
1258 return ops;
1259}
1260EXPORT_SYMBOL_GPL(xt_hook_link);
1261
1262/**
1263 * xt_hook_unlink - remove hooks for a table
1264 * @ops: nf_hook_ops array as returned by nf_hook_link
1265 * @hook_mask: the very same mask that was passed to nf_hook_link
1266 */
1267void xt_hook_unlink(const struct xt_table *table, struct nf_hook_ops *ops)
1268{
1269 nf_unregister_hooks(ops, hweight32(table->valid_hooks));
1270 kfree(ops);
1271}
1272EXPORT_SYMBOL_GPL(xt_hook_unlink);
1273
76108cea 1274int xt_proto_init(struct net *net, u_int8_t af)
2e4e6a17
HW
1275{
1276#ifdef CONFIG_PROC_FS
1277 char buf[XT_FUNCTION_MAXNAMELEN];
1278 struct proc_dir_entry *proc;
1279#endif
1280
7e9c6eeb 1281 if (af >= ARRAY_SIZE(xt_prefix))
2e4e6a17
HW
1282 return -EINVAL;
1283
1284
1285#ifdef CONFIG_PROC_FS
ce18afe5 1286 strlcpy(buf, xt_prefix[af], sizeof(buf));
2e4e6a17 1287 strlcat(buf, FORMAT_TABLES, sizeof(buf));
8b169240
DL
1288 proc = proc_create_data(buf, 0440, net->proc_net, &xt_table_ops,
1289 (void *)(unsigned long)af);
2e4e6a17
HW
1290 if (!proc)
1291 goto out;
2e4e6a17 1292
ce18afe5 1293 strlcpy(buf, xt_prefix[af], sizeof(buf));
2e4e6a17 1294 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
8b169240
DL
1295 proc = proc_create_data(buf, 0440, net->proc_net, &xt_match_ops,
1296 (void *)(unsigned long)af);
2e4e6a17
HW
1297 if (!proc)
1298 goto out_remove_tables;
2e4e6a17 1299
ce18afe5 1300 strlcpy(buf, xt_prefix[af], sizeof(buf));
2e4e6a17 1301 strlcat(buf, FORMAT_TARGETS, sizeof(buf));
8b169240
DL
1302 proc = proc_create_data(buf, 0440, net->proc_net, &xt_target_ops,
1303 (void *)(unsigned long)af);
2e4e6a17
HW
1304 if (!proc)
1305 goto out_remove_matches;
2e4e6a17
HW
1306#endif
1307
1308 return 0;
1309
1310#ifdef CONFIG_PROC_FS
1311out_remove_matches:
ce18afe5 1312 strlcpy(buf, xt_prefix[af], sizeof(buf));
2e4e6a17 1313 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
3cb609d5 1314 proc_net_remove(net, buf);
2e4e6a17
HW
1315
1316out_remove_tables:
ce18afe5 1317 strlcpy(buf, xt_prefix[af], sizeof(buf));
2e4e6a17 1318 strlcat(buf, FORMAT_TABLES, sizeof(buf));
3cb609d5 1319 proc_net_remove(net, buf);
2e4e6a17
HW
1320out:
1321 return -1;
1322#endif
1323}
1324EXPORT_SYMBOL_GPL(xt_proto_init);
1325
76108cea 1326void xt_proto_fini(struct net *net, u_int8_t af)
2e4e6a17
HW
1327{
1328#ifdef CONFIG_PROC_FS
1329 char buf[XT_FUNCTION_MAXNAMELEN];
1330
ce18afe5 1331 strlcpy(buf, xt_prefix[af], sizeof(buf));
2e4e6a17 1332 strlcat(buf, FORMAT_TABLES, sizeof(buf));
3cb609d5 1333 proc_net_remove(net, buf);
2e4e6a17 1334
ce18afe5 1335 strlcpy(buf, xt_prefix[af], sizeof(buf));
2e4e6a17 1336 strlcat(buf, FORMAT_TARGETS, sizeof(buf));
3cb609d5 1337 proc_net_remove(net, buf);
2e4e6a17 1338
ce18afe5 1339 strlcpy(buf, xt_prefix[af], sizeof(buf));
2e4e6a17 1340 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
3cb609d5 1341 proc_net_remove(net, buf);
2e4e6a17
HW
1342#endif /*CONFIG_PROC_FS*/
1343}
1344EXPORT_SYMBOL_GPL(xt_proto_fini);
1345
8d870052
AD
1346static int __net_init xt_net_init(struct net *net)
1347{
1348 int i;
1349
7e9c6eeb 1350 for (i = 0; i < NFPROTO_NUMPROTO; i++)
8d870052
AD
1351 INIT_LIST_HEAD(&net->xt.tables[i]);
1352 return 0;
1353}
1354
1355static struct pernet_operations xt_net_ops = {
1356 .init = xt_net_init,
1357};
2e4e6a17
HW
1358
1359static int __init xt_init(void)
1360{
942e4a2b
SH
1361 unsigned int i;
1362 int rv;
1363
1364 for_each_possible_cpu(i) {
7f5c6d4f 1365 seqcount_init(&per_cpu(xt_recseq, i));
942e4a2b 1366 }
2e4e6a17 1367
7e9c6eeb 1368 xt = kmalloc(sizeof(struct xt_af) * NFPROTO_NUMPROTO, GFP_KERNEL);
2e4e6a17
HW
1369 if (!xt)
1370 return -ENOMEM;
1371
7e9c6eeb 1372 for (i = 0; i < NFPROTO_NUMPROTO; i++) {
9e19bb6d 1373 mutex_init(&xt[i].mutex);
2722971c
DM
1374#ifdef CONFIG_COMPAT
1375 mutex_init(&xt[i].compat_mutex);
255d0dc3 1376 xt[i].compat_tab = NULL;
2722971c 1377#endif
2e4e6a17
HW
1378 INIT_LIST_HEAD(&xt[i].target);
1379 INIT_LIST_HEAD(&xt[i].match);
2e4e6a17 1380 }
8d870052
AD
1381 rv = register_pernet_subsys(&xt_net_ops);
1382 if (rv < 0)
1383 kfree(xt);
1384 return rv;
2e4e6a17
HW
1385}
1386
1387static void __exit xt_fini(void)
1388{
8d870052 1389 unregister_pernet_subsys(&xt_net_ops);
2e4e6a17
HW
1390 kfree(xt);
1391}
1392
1393module_init(xt_init);
1394module_exit(xt_fini);
1395