Merge branch 'pm-sleep'
[deliverable/linux.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>
f229f6ce 5 * Copyright (C) 2006-2012 Patrick McHardy <kaber@trash.net>
2e4e6a17
HW
6 *
7 * Based on existing ip_tables code which is
8 * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
9 * Copyright (C) 2000-2005 Netfilter Core Team <coreteam@netfilter.org>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
14 *
15 */
be91fd5e 16#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
2e4e6a17 17#include <linux/kernel.h>
3a9a231d 18#include <linux/module.h>
2e4e6a17
HW
19#include <linux/socket.h>
20#include <linux/net.h>
21#include <linux/proc_fs.h>
22#include <linux/seq_file.h>
23#include <linux/string.h>
24#include <linux/vmalloc.h>
9e19bb6d 25#include <linux/mutex.h>
d7fe0f24 26#include <linux/mm.h>
5a0e3ad6 27#include <linux/slab.h>
fbabf31e 28#include <linux/audit.h>
457c4cbc 29#include <net/net_namespace.h>
2e4e6a17
HW
30
31#include <linux/netfilter/x_tables.h>
32#include <linux/netfilter_arp.h>
e3eaa991
JE
33#include <linux/netfilter_ipv4/ip_tables.h>
34#include <linux/netfilter_ipv6/ip6_tables.h>
35#include <linux/netfilter_arp/arp_tables.h>
9e19bb6d 36
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37MODULE_LICENSE("GPL");
38MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
043ef46c 39MODULE_DESCRIPTION("{ip,ip6,arp,eb}_tables backend module");
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HW
40
41#define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1))
42
b386d9f5 43struct compat_delta {
255d0dc3
ED
44 unsigned int offset; /* offset in kernel */
45 int delta; /* delta in 32bit user land */
b386d9f5
PM
46};
47
2e4e6a17 48struct xt_af {
9e19bb6d 49 struct mutex mutex;
2e4e6a17
HW
50 struct list_head match;
51 struct list_head target;
b386d9f5 52#ifdef CONFIG_COMPAT
2722971c 53 struct mutex compat_mutex;
255d0dc3
ED
54 struct compat_delta *compat_tab;
55 unsigned int number; /* number of slots in compat_tab[] */
56 unsigned int cur; /* number of used slots in compat_tab[] */
b386d9f5 57#endif
2e4e6a17
HW
58};
59
60static struct xt_af *xt;
61
7e9c6eeb
JE
62static const char *const xt_prefix[NFPROTO_NUMPROTO] = {
63 [NFPROTO_UNSPEC] = "x",
64 [NFPROTO_IPV4] = "ip",
65 [NFPROTO_ARP] = "arp",
66 [NFPROTO_BRIDGE] = "eb",
67 [NFPROTO_IPV6] = "ip6",
37f9f733
PM
68};
69
f3c5c1bf
JE
70/* Allow this many total (re)entries. */
71static const unsigned int xt_jumpstack_multiplier = 2;
72
2e4e6a17
HW
73/* Registration hooks for targets. */
74int
a45049c5 75xt_register_target(struct xt_target *target)
2e4e6a17 76{
76108cea
JE
77 u_int8_t af = target->family;
78 int ret;
2e4e6a17 79
9e19bb6d 80 ret = mutex_lock_interruptible(&xt[af].mutex);
2e4e6a17
HW
81 if (ret != 0)
82 return ret;
83 list_add(&target->list, &xt[af].target);
9e19bb6d 84 mutex_unlock(&xt[af].mutex);
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HW
85 return ret;
86}
87EXPORT_SYMBOL(xt_register_target);
88
89void
a45049c5 90xt_unregister_target(struct xt_target *target)
2e4e6a17 91{
76108cea 92 u_int8_t af = target->family;
a45049c5 93
9e19bb6d 94 mutex_lock(&xt[af].mutex);
df0933dc 95 list_del(&target->list);
9e19bb6d 96 mutex_unlock(&xt[af].mutex);
2e4e6a17
HW
97}
98EXPORT_SYMBOL(xt_unregister_target);
99
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100int
101xt_register_targets(struct xt_target *target, unsigned int n)
102{
103 unsigned int i;
104 int err = 0;
105
106 for (i = 0; i < n; i++) {
107 err = xt_register_target(&target[i]);
108 if (err)
109 goto err;
110 }
111 return err;
112
113err:
114 if (i > 0)
115 xt_unregister_targets(target, i);
116 return err;
117}
118EXPORT_SYMBOL(xt_register_targets);
119
120void
121xt_unregister_targets(struct xt_target *target, unsigned int n)
122{
f68c5301
CG
123 while (n-- > 0)
124 xt_unregister_target(&target[n]);
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125}
126EXPORT_SYMBOL(xt_unregister_targets);
127
2e4e6a17 128int
a45049c5 129xt_register_match(struct xt_match *match)
2e4e6a17 130{
76108cea
JE
131 u_int8_t af = match->family;
132 int ret;
2e4e6a17 133
9e19bb6d 134 ret = mutex_lock_interruptible(&xt[af].mutex);
2e4e6a17
HW
135 if (ret != 0)
136 return ret;
137
138 list_add(&match->list, &xt[af].match);
9e19bb6d 139 mutex_unlock(&xt[af].mutex);
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HW
140
141 return ret;
142}
143EXPORT_SYMBOL(xt_register_match);
144
145void
a45049c5 146xt_unregister_match(struct xt_match *match)
2e4e6a17 147{
76108cea 148 u_int8_t af = match->family;
a45049c5 149
9e19bb6d 150 mutex_lock(&xt[af].mutex);
df0933dc 151 list_del(&match->list);
9e19bb6d 152 mutex_unlock(&xt[af].mutex);
2e4e6a17
HW
153}
154EXPORT_SYMBOL(xt_unregister_match);
155
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156int
157xt_register_matches(struct xt_match *match, unsigned int n)
158{
159 unsigned int i;
160 int err = 0;
161
162 for (i = 0; i < n; i++) {
163 err = xt_register_match(&match[i]);
164 if (err)
165 goto err;
166 }
167 return err;
168
169err:
170 if (i > 0)
171 xt_unregister_matches(match, i);
172 return err;
173}
174EXPORT_SYMBOL(xt_register_matches);
175
176void
177xt_unregister_matches(struct xt_match *match, unsigned int n)
178{
f68c5301
CG
179 while (n-- > 0)
180 xt_unregister_match(&match[n]);
52d9c42e
PM
181}
182EXPORT_SYMBOL(xt_unregister_matches);
183
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HW
184
185/*
186 * These are weird, but module loading must not be done with mutex
187 * held (since they will register), and we have to have a single
adb00ae2 188 * function to use.
2e4e6a17
HW
189 */
190
191/* Find match, grabs ref. Returns ERR_PTR() on error. */
76108cea 192struct xt_match *xt_find_match(u8 af, const char *name, u8 revision)
2e4e6a17
HW
193{
194 struct xt_match *m;
42046e2e 195 int err = -ENOENT;
2e4e6a17 196
9e19bb6d 197 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
2e4e6a17
HW
198 return ERR_PTR(-EINTR);
199
200 list_for_each_entry(m, &xt[af].match, list) {
201 if (strcmp(m->name, name) == 0) {
202 if (m->revision == revision) {
203 if (try_module_get(m->me)) {
9e19bb6d 204 mutex_unlock(&xt[af].mutex);
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HW
205 return m;
206 }
207 } else
208 err = -EPROTOTYPE; /* Found something. */
209 }
210 }
9e19bb6d 211 mutex_unlock(&xt[af].mutex);
55b69e91
JE
212
213 if (af != NFPROTO_UNSPEC)
214 /* Try searching again in the family-independent list */
215 return xt_find_match(NFPROTO_UNSPEC, name, revision);
216
2e4e6a17
HW
217 return ERR_PTR(err);
218}
219EXPORT_SYMBOL(xt_find_match);
220
fd0ec0e6
JE
221struct xt_match *
222xt_request_find_match(uint8_t nfproto, const char *name, uint8_t revision)
223{
224 struct xt_match *match;
225
adb00ae2
SH
226 match = xt_find_match(nfproto, name, revision);
227 if (IS_ERR(match)) {
228 request_module("%st_%s", xt_prefix[nfproto], name);
229 match = xt_find_match(nfproto, name, revision);
230 }
231
232 return match;
fd0ec0e6
JE
233}
234EXPORT_SYMBOL_GPL(xt_request_find_match);
235
2e4e6a17 236/* Find target, grabs ref. Returns ERR_PTR() on error. */
76108cea 237struct xt_target *xt_find_target(u8 af, const char *name, u8 revision)
2e4e6a17
HW
238{
239 struct xt_target *t;
42046e2e 240 int err = -ENOENT;
2e4e6a17 241
9e19bb6d 242 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
2e4e6a17
HW
243 return ERR_PTR(-EINTR);
244
245 list_for_each_entry(t, &xt[af].target, list) {
246 if (strcmp(t->name, name) == 0) {
247 if (t->revision == revision) {
248 if (try_module_get(t->me)) {
9e19bb6d 249 mutex_unlock(&xt[af].mutex);
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HW
250 return t;
251 }
252 } else
253 err = -EPROTOTYPE; /* Found something. */
254 }
255 }
9e19bb6d 256 mutex_unlock(&xt[af].mutex);
55b69e91
JE
257
258 if (af != NFPROTO_UNSPEC)
259 /* Try searching again in the family-independent list */
260 return xt_find_target(NFPROTO_UNSPEC, name, revision);
261
2e4e6a17
HW
262 return ERR_PTR(err);
263}
264EXPORT_SYMBOL(xt_find_target);
265
76108cea 266struct xt_target *xt_request_find_target(u8 af, const char *name, u8 revision)
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HW
267{
268 struct xt_target *target;
269
adb00ae2
SH
270 target = xt_find_target(af, name, revision);
271 if (IS_ERR(target)) {
272 request_module("%st_%s", xt_prefix[af], name);
273 target = xt_find_target(af, name, revision);
274 }
275
276 return target;
2e4e6a17
HW
277}
278EXPORT_SYMBOL_GPL(xt_request_find_target);
279
76108cea 280static int match_revfn(u8 af, const char *name, u8 revision, int *bestp)
2e4e6a17 281{
5452e425 282 const struct xt_match *m;
2e4e6a17
HW
283 int have_rev = 0;
284
285 list_for_each_entry(m, &xt[af].match, list) {
286 if (strcmp(m->name, name) == 0) {
287 if (m->revision > *bestp)
288 *bestp = m->revision;
289 if (m->revision == revision)
290 have_rev = 1;
291 }
292 }
656caff2
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293
294 if (af != NFPROTO_UNSPEC && !have_rev)
295 return match_revfn(NFPROTO_UNSPEC, name, revision, bestp);
296
2e4e6a17
HW
297 return have_rev;
298}
299
76108cea 300static int target_revfn(u8 af, const char *name, u8 revision, int *bestp)
2e4e6a17 301{
5452e425 302 const struct xt_target *t;
2e4e6a17
HW
303 int have_rev = 0;
304
305 list_for_each_entry(t, &xt[af].target, list) {
306 if (strcmp(t->name, name) == 0) {
307 if (t->revision > *bestp)
308 *bestp = t->revision;
309 if (t->revision == revision)
310 have_rev = 1;
311 }
312 }
656caff2
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313
314 if (af != NFPROTO_UNSPEC && !have_rev)
315 return target_revfn(NFPROTO_UNSPEC, name, revision, bestp);
316
2e4e6a17
HW
317 return have_rev;
318}
319
320/* Returns true or false (if no such extension at all) */
76108cea 321int xt_find_revision(u8 af, const char *name, u8 revision, int target,
2e4e6a17
HW
322 int *err)
323{
324 int have_rev, best = -1;
325
9e19bb6d 326 if (mutex_lock_interruptible(&xt[af].mutex) != 0) {
2e4e6a17
HW
327 *err = -EINTR;
328 return 1;
329 }
330 if (target == 1)
331 have_rev = target_revfn(af, name, revision, &best);
332 else
333 have_rev = match_revfn(af, name, revision, &best);
9e19bb6d 334 mutex_unlock(&xt[af].mutex);
2e4e6a17
HW
335
336 /* Nothing at all? Return 0 to try loading module. */
337 if (best == -1) {
338 *err = -ENOENT;
339 return 0;
340 }
341
342 *err = best;
343 if (!have_rev)
344 *err = -EPROTONOSUPPORT;
345 return 1;
346}
347EXPORT_SYMBOL_GPL(xt_find_revision);
348
5b76c494
JE
349static char *
350textify_hooks(char *buf, size_t size, unsigned int mask, uint8_t nfproto)
45185364 351{
5b76c494 352 static const char *const inetbr_names[] = {
45185364
JE
353 "PREROUTING", "INPUT", "FORWARD",
354 "OUTPUT", "POSTROUTING", "BROUTING",
355 };
5b76c494
JE
356 static const char *const arp_names[] = {
357 "INPUT", "FORWARD", "OUTPUT",
358 };
359 const char *const *names;
360 unsigned int i, max;
45185364
JE
361 char *p = buf;
362 bool np = false;
363 int res;
364
5b76c494
JE
365 names = (nfproto == NFPROTO_ARP) ? arp_names : inetbr_names;
366 max = (nfproto == NFPROTO_ARP) ? ARRAY_SIZE(arp_names) :
367 ARRAY_SIZE(inetbr_names);
45185364 368 *p = '\0';
5b76c494 369 for (i = 0; i < max; ++i) {
45185364
JE
370 if (!(mask & (1 << i)))
371 continue;
372 res = snprintf(p, size, "%s%s", np ? "/" : "", names[i]);
373 if (res > 0) {
374 size -= res;
375 p += res;
376 }
377 np = true;
378 }
379
380 return buf;
381}
382
916a917d 383int xt_check_match(struct xt_mtchk_param *par,
9b4fce7a 384 unsigned int size, u_int8_t proto, bool inv_proto)
37f9f733 385{
bd414ee6
JE
386 int ret;
387
9b4fce7a
JE
388 if (XT_ALIGN(par->match->matchsize) != size &&
389 par->match->matchsize != -1) {
043ef46c
JE
390 /*
391 * ebt_among is exempt from centralized matchsize checking
392 * because it uses a dynamic-size data set.
393 */
b402405d
JE
394 pr_err("%s_tables: %s.%u match: invalid size "
395 "%u (kernel) != (user) %u\n",
916a917d 396 xt_prefix[par->family], par->match->name,
b402405d 397 par->match->revision,
9b4fce7a 398 XT_ALIGN(par->match->matchsize), size);
37f9f733
PM
399 return -EINVAL;
400 }
9b4fce7a
JE
401 if (par->match->table != NULL &&
402 strcmp(par->match->table, par->table) != 0) {
3dd5d7e3 403 pr_err("%s_tables: %s match: only valid in %s table, not %s\n",
916a917d 404 xt_prefix[par->family], par->match->name,
9b4fce7a 405 par->match->table, par->table);
37f9f733
PM
406 return -EINVAL;
407 }
9b4fce7a 408 if (par->match->hooks && (par->hook_mask & ~par->match->hooks) != 0) {
45185364
JE
409 char used[64], allow[64];
410
3dd5d7e3 411 pr_err("%s_tables: %s match: used from hooks %s, but only "
45185364 412 "valid from %s\n",
916a917d 413 xt_prefix[par->family], par->match->name,
5b76c494
JE
414 textify_hooks(used, sizeof(used), par->hook_mask,
415 par->family),
416 textify_hooks(allow, sizeof(allow), par->match->hooks,
417 par->family));
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418 return -EINVAL;
419 }
9b4fce7a 420 if (par->match->proto && (par->match->proto != proto || inv_proto)) {
3dd5d7e3 421 pr_err("%s_tables: %s match: only valid for protocol %u\n",
916a917d
JE
422 xt_prefix[par->family], par->match->name,
423 par->match->proto);
37f9f733
PM
424 return -EINVAL;
425 }
bd414ee6
JE
426 if (par->match->checkentry != NULL) {
427 ret = par->match->checkentry(par);
428 if (ret < 0)
429 return ret;
430 else if (ret > 0)
431 /* Flag up potential errors. */
432 return -EIO;
433 }
37f9f733
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434 return 0;
435}
436EXPORT_SYMBOL_GPL(xt_check_match);
437
2722971c 438#ifdef CONFIG_COMPAT
255d0dc3 439int xt_compat_add_offset(u_int8_t af, unsigned int offset, int delta)
b386d9f5 440{
255d0dc3 441 struct xt_af *xp = &xt[af];
b386d9f5 442
255d0dc3
ED
443 if (!xp->compat_tab) {
444 if (!xp->number)
445 return -EINVAL;
446 xp->compat_tab = vmalloc(sizeof(struct compat_delta) * xp->number);
447 if (!xp->compat_tab)
448 return -ENOMEM;
449 xp->cur = 0;
450 }
b386d9f5 451
255d0dc3
ED
452 if (xp->cur >= xp->number)
453 return -EINVAL;
b386d9f5 454
255d0dc3
ED
455 if (xp->cur)
456 delta += xp->compat_tab[xp->cur - 1].delta;
457 xp->compat_tab[xp->cur].offset = offset;
458 xp->compat_tab[xp->cur].delta = delta;
459 xp->cur++;
b386d9f5
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460 return 0;
461}
462EXPORT_SYMBOL_GPL(xt_compat_add_offset);
463
76108cea 464void xt_compat_flush_offsets(u_int8_t af)
b386d9f5 465{
255d0dc3
ED
466 if (xt[af].compat_tab) {
467 vfree(xt[af].compat_tab);
468 xt[af].compat_tab = NULL;
469 xt[af].number = 0;
5a6351ee 470 xt[af].cur = 0;
b386d9f5
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471 }
472}
473EXPORT_SYMBOL_GPL(xt_compat_flush_offsets);
474
3e5e524f 475int xt_compat_calc_jump(u_int8_t af, unsigned int offset)
b386d9f5 476{
255d0dc3
ED
477 struct compat_delta *tmp = xt[af].compat_tab;
478 int mid, left = 0, right = xt[af].cur - 1;
479
480 while (left <= right) {
481 mid = (left + right) >> 1;
482 if (offset > tmp[mid].offset)
483 left = mid + 1;
484 else if (offset < tmp[mid].offset)
485 right = mid - 1;
486 else
487 return mid ? tmp[mid - 1].delta : 0;
488 }
5a6351ee 489 return left ? tmp[left - 1].delta : 0;
b386d9f5
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490}
491EXPORT_SYMBOL_GPL(xt_compat_calc_jump);
492
255d0dc3
ED
493void xt_compat_init_offsets(u_int8_t af, unsigned int number)
494{
495 xt[af].number = number;
496 xt[af].cur = 0;
497}
498EXPORT_SYMBOL(xt_compat_init_offsets);
499
5452e425 500int xt_compat_match_offset(const struct xt_match *match)
2722971c 501{
9fa492cd
PM
502 u_int16_t csize = match->compatsize ? : match->matchsize;
503 return XT_ALIGN(match->matchsize) - COMPAT_XT_ALIGN(csize);
504}
505EXPORT_SYMBOL_GPL(xt_compat_match_offset);
506
89566951 507int xt_compat_match_from_user(struct xt_entry_match *m, void **dstptr,
b0a6363c 508 unsigned int *size)
9fa492cd 509{
5452e425 510 const struct xt_match *match = m->u.kernel.match;
9fa492cd
PM
511 struct compat_xt_entry_match *cm = (struct compat_xt_entry_match *)m;
512 int pad, off = xt_compat_match_offset(match);
513 u_int16_t msize = cm->u.user.match_size;
514
515 m = *dstptr;
516 memcpy(m, cm, sizeof(*cm));
517 if (match->compat_from_user)
518 match->compat_from_user(m->data, cm->data);
519 else
520 memcpy(m->data, cm->data, msize - sizeof(*cm));
521 pad = XT_ALIGN(match->matchsize) - match->matchsize;
522 if (pad > 0)
523 memset(m->data + match->matchsize, 0, pad);
524
525 msize += off;
526 m->u.user.match_size = msize;
527
528 *size += off;
529 *dstptr += msize;
89566951 530 return 0;
9fa492cd
PM
531}
532EXPORT_SYMBOL_GPL(xt_compat_match_from_user);
533
739674fb
JE
534int xt_compat_match_to_user(const struct xt_entry_match *m,
535 void __user **dstptr, unsigned int *size)
9fa492cd 536{
5452e425 537 const struct xt_match *match = m->u.kernel.match;
9fa492cd
PM
538 struct compat_xt_entry_match __user *cm = *dstptr;
539 int off = xt_compat_match_offset(match);
540 u_int16_t msize = m->u.user.match_size - off;
541
542 if (copy_to_user(cm, m, sizeof(*cm)) ||
a18aa31b
PM
543 put_user(msize, &cm->u.user.match_size) ||
544 copy_to_user(cm->u.user.name, m->u.kernel.match->name,
545 strlen(m->u.kernel.match->name) + 1))
601e68e1 546 return -EFAULT;
9fa492cd
PM
547
548 if (match->compat_to_user) {
549 if (match->compat_to_user((void __user *)cm->data, m->data))
550 return -EFAULT;
551 } else {
552 if (copy_to_user(cm->data, m->data, msize - sizeof(*cm)))
553 return -EFAULT;
2722971c 554 }
9fa492cd
PM
555
556 *size -= off;
557 *dstptr += msize;
558 return 0;
2722971c 559}
9fa492cd
PM
560EXPORT_SYMBOL_GPL(xt_compat_match_to_user);
561#endif /* CONFIG_COMPAT */
2722971c 562
916a917d 563int xt_check_target(struct xt_tgchk_param *par,
af5d6dc2 564 unsigned int size, u_int8_t proto, bool inv_proto)
37f9f733 565{
d6b00a53
JE
566 int ret;
567
af5d6dc2 568 if (XT_ALIGN(par->target->targetsize) != size) {
b402405d
JE
569 pr_err("%s_tables: %s.%u target: invalid size "
570 "%u (kernel) != (user) %u\n",
916a917d 571 xt_prefix[par->family], par->target->name,
b402405d 572 par->target->revision,
af5d6dc2 573 XT_ALIGN(par->target->targetsize), size);
37f9f733
PM
574 return -EINVAL;
575 }
af5d6dc2
JE
576 if (par->target->table != NULL &&
577 strcmp(par->target->table, par->table) != 0) {
3dd5d7e3 578 pr_err("%s_tables: %s target: only valid in %s table, not %s\n",
916a917d 579 xt_prefix[par->family], par->target->name,
af5d6dc2 580 par->target->table, par->table);
37f9f733
PM
581 return -EINVAL;
582 }
af5d6dc2 583 if (par->target->hooks && (par->hook_mask & ~par->target->hooks) != 0) {
45185364
JE
584 char used[64], allow[64];
585
3dd5d7e3 586 pr_err("%s_tables: %s target: used from hooks %s, but only "
45185364 587 "usable from %s\n",
916a917d 588 xt_prefix[par->family], par->target->name,
5b76c494
JE
589 textify_hooks(used, sizeof(used), par->hook_mask,
590 par->family),
591 textify_hooks(allow, sizeof(allow), par->target->hooks,
592 par->family));
37f9f733
PM
593 return -EINVAL;
594 }
af5d6dc2 595 if (par->target->proto && (par->target->proto != proto || inv_proto)) {
3dd5d7e3 596 pr_err("%s_tables: %s target: only valid for protocol %u\n",
916a917d 597 xt_prefix[par->family], par->target->name,
af5d6dc2 598 par->target->proto);
37f9f733
PM
599 return -EINVAL;
600 }
d6b00a53
JE
601 if (par->target->checkentry != NULL) {
602 ret = par->target->checkentry(par);
603 if (ret < 0)
604 return ret;
605 else if (ret > 0)
606 /* Flag up potential errors. */
607 return -EIO;
608 }
37f9f733
PM
609 return 0;
610}
611EXPORT_SYMBOL_GPL(xt_check_target);
612
2722971c 613#ifdef CONFIG_COMPAT
5452e425 614int xt_compat_target_offset(const struct xt_target *target)
2722971c 615{
9fa492cd
PM
616 u_int16_t csize = target->compatsize ? : target->targetsize;
617 return XT_ALIGN(target->targetsize) - COMPAT_XT_ALIGN(csize);
618}
619EXPORT_SYMBOL_GPL(xt_compat_target_offset);
620
621void xt_compat_target_from_user(struct xt_entry_target *t, void **dstptr,
b0a6363c 622 unsigned int *size)
9fa492cd 623{
5452e425 624 const struct xt_target *target = t->u.kernel.target;
9fa492cd
PM
625 struct compat_xt_entry_target *ct = (struct compat_xt_entry_target *)t;
626 int pad, off = xt_compat_target_offset(target);
627 u_int16_t tsize = ct->u.user.target_size;
628
629 t = *dstptr;
630 memcpy(t, ct, sizeof(*ct));
631 if (target->compat_from_user)
632 target->compat_from_user(t->data, ct->data);
633 else
634 memcpy(t->data, ct->data, tsize - sizeof(*ct));
635 pad = XT_ALIGN(target->targetsize) - target->targetsize;
636 if (pad > 0)
637 memset(t->data + target->targetsize, 0, pad);
638
639 tsize += off;
640 t->u.user.target_size = tsize;
641
642 *size += off;
643 *dstptr += tsize;
644}
645EXPORT_SYMBOL_GPL(xt_compat_target_from_user);
646
739674fb
JE
647int xt_compat_target_to_user(const struct xt_entry_target *t,
648 void __user **dstptr, unsigned int *size)
9fa492cd 649{
5452e425 650 const struct xt_target *target = t->u.kernel.target;
9fa492cd
PM
651 struct compat_xt_entry_target __user *ct = *dstptr;
652 int off = xt_compat_target_offset(target);
653 u_int16_t tsize = t->u.user.target_size - off;
654
655 if (copy_to_user(ct, t, sizeof(*ct)) ||
a18aa31b
PM
656 put_user(tsize, &ct->u.user.target_size) ||
657 copy_to_user(ct->u.user.name, t->u.kernel.target->name,
658 strlen(t->u.kernel.target->name) + 1))
601e68e1 659 return -EFAULT;
9fa492cd
PM
660
661 if (target->compat_to_user) {
662 if (target->compat_to_user((void __user *)ct->data, t->data))
663 return -EFAULT;
664 } else {
665 if (copy_to_user(ct->data, t->data, tsize - sizeof(*ct)))
666 return -EFAULT;
2722971c 667 }
9fa492cd
PM
668
669 *size -= off;
670 *dstptr += tsize;
671 return 0;
2722971c 672}
9fa492cd 673EXPORT_SYMBOL_GPL(xt_compat_target_to_user);
2722971c
DM
674#endif
675
2e4e6a17
HW
676struct xt_table_info *xt_alloc_table_info(unsigned int size)
677{
678 struct xt_table_info *newinfo;
679 int cpu;
680
681 /* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */
4481374c 682 if ((SMP_ALIGN(size) >> PAGE_SHIFT) + 2 > totalram_pages)
2e4e6a17
HW
683 return NULL;
684
259d4e41 685 newinfo = kzalloc(XT_TABLE_INFO_SZ, GFP_KERNEL);
2e4e6a17
HW
686 if (!newinfo)
687 return NULL;
688
689 newinfo->size = size;
690
6f912042 691 for_each_possible_cpu(cpu) {
2e4e6a17
HW
692 if (size <= PAGE_SIZE)
693 newinfo->entries[cpu] = kmalloc_node(size,
694 GFP_KERNEL,
695 cpu_to_node(cpu));
696 else
697 newinfo->entries[cpu] = vmalloc_node(size,
698 cpu_to_node(cpu));
699
700 if (newinfo->entries[cpu] == NULL) {
701 xt_free_table_info(newinfo);
702 return NULL;
703 }
704 }
705
706 return newinfo;
707}
708EXPORT_SYMBOL(xt_alloc_table_info);
709
710void xt_free_table_info(struct xt_table_info *info)
711{
712 int cpu;
713
6f912042 714 for_each_possible_cpu(cpu) {
2e4e6a17
HW
715 if (info->size <= PAGE_SIZE)
716 kfree(info->entries[cpu]);
717 else
718 vfree(info->entries[cpu]);
719 }
f3c5c1bf
JE
720
721 if (info->jumpstack != NULL) {
722 if (sizeof(void *) * info->stacksize > PAGE_SIZE) {
723 for_each_possible_cpu(cpu)
724 vfree(info->jumpstack[cpu]);
725 } else {
726 for_each_possible_cpu(cpu)
727 kfree(info->jumpstack[cpu]);
728 }
729 }
730
731 if (sizeof(void **) * nr_cpu_ids > PAGE_SIZE)
732 vfree(info->jumpstack);
733 else
734 kfree(info->jumpstack);
7489aec8
ED
735
736 free_percpu(info->stackptr);
f3c5c1bf 737
2e4e6a17
HW
738 kfree(info);
739}
740EXPORT_SYMBOL(xt_free_table_info);
741
742/* Find table by name, grabs mutex & ref. Returns ERR_PTR() on error. */
76108cea
JE
743struct xt_table *xt_find_table_lock(struct net *net, u_int8_t af,
744 const char *name)
2e4e6a17
HW
745{
746 struct xt_table *t;
747
9e19bb6d 748 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
2e4e6a17
HW
749 return ERR_PTR(-EINTR);
750
8d870052 751 list_for_each_entry(t, &net->xt.tables[af], list)
2e4e6a17
HW
752 if (strcmp(t->name, name) == 0 && try_module_get(t->me))
753 return t;
9e19bb6d 754 mutex_unlock(&xt[af].mutex);
2e4e6a17
HW
755 return NULL;
756}
757EXPORT_SYMBOL_GPL(xt_find_table_lock);
758
759void xt_table_unlock(struct xt_table *table)
760{
9e19bb6d 761 mutex_unlock(&xt[table->af].mutex);
2e4e6a17
HW
762}
763EXPORT_SYMBOL_GPL(xt_table_unlock);
764
2722971c 765#ifdef CONFIG_COMPAT
76108cea 766void xt_compat_lock(u_int8_t af)
2722971c
DM
767{
768 mutex_lock(&xt[af].compat_mutex);
769}
770EXPORT_SYMBOL_GPL(xt_compat_lock);
771
76108cea 772void xt_compat_unlock(u_int8_t af)
2722971c
DM
773{
774 mutex_unlock(&xt[af].compat_mutex);
775}
776EXPORT_SYMBOL_GPL(xt_compat_unlock);
777#endif
2e4e6a17 778
7f5c6d4f
ED
779DEFINE_PER_CPU(seqcount_t, xt_recseq);
780EXPORT_PER_CPU_SYMBOL_GPL(xt_recseq);
942e4a2b 781
f3c5c1bf
JE
782static int xt_jumpstack_alloc(struct xt_table_info *i)
783{
784 unsigned int size;
785 int cpu;
786
7489aec8 787 i->stackptr = alloc_percpu(unsigned int);
f3c5c1bf
JE
788 if (i->stackptr == NULL)
789 return -ENOMEM;
f3c5c1bf
JE
790
791 size = sizeof(void **) * nr_cpu_ids;
792 if (size > PAGE_SIZE)
3dbd4439 793 i->jumpstack = vzalloc(size);
f3c5c1bf 794 else
3dbd4439 795 i->jumpstack = kzalloc(size, GFP_KERNEL);
f3c5c1bf
JE
796 if (i->jumpstack == NULL)
797 return -ENOMEM;
f3c5c1bf
JE
798
799 i->stacksize *= xt_jumpstack_multiplier;
800 size = sizeof(void *) * i->stacksize;
801 for_each_possible_cpu(cpu) {
802 if (size > PAGE_SIZE)
803 i->jumpstack[cpu] = vmalloc_node(size,
804 cpu_to_node(cpu));
805 else
806 i->jumpstack[cpu] = kmalloc_node(size,
807 GFP_KERNEL, cpu_to_node(cpu));
808 if (i->jumpstack[cpu] == NULL)
809 /*
810 * Freeing will be done later on by the callers. The
811 * chain is: xt_replace_table -> __do_replace ->
812 * do_replace -> xt_free_table_info.
813 */
814 return -ENOMEM;
815 }
816
817 return 0;
818}
942e4a2b 819
2e4e6a17
HW
820struct xt_table_info *
821xt_replace_table(struct xt_table *table,
822 unsigned int num_counters,
823 struct xt_table_info *newinfo,
824 int *error)
825{
942e4a2b 826 struct xt_table_info *private;
f3c5c1bf 827 int ret;
2e4e6a17 828
d97a9e47
JE
829 ret = xt_jumpstack_alloc(newinfo);
830 if (ret < 0) {
831 *error = ret;
832 return NULL;
833 }
834
2e4e6a17 835 /* Do the substitution. */
942e4a2b 836 local_bh_disable();
2e4e6a17 837 private = table->private;
942e4a2b 838
2e4e6a17
HW
839 /* Check inside lock: is the old number correct? */
840 if (num_counters != private->number) {
be91fd5e 841 pr_debug("num_counters != table->private->number (%u/%u)\n",
2e4e6a17 842 num_counters, private->number);
942e4a2b 843 local_bh_enable();
2e4e6a17
HW
844 *error = -EAGAIN;
845 return NULL;
846 }
2e4e6a17 847
942e4a2b 848 newinfo->initial_entries = private->initial_entries;
b416c144
WD
849 /*
850 * Ensure contents of newinfo are visible before assigning to
851 * private.
852 */
853 smp_wmb();
854 table->private = newinfo;
942e4a2b
SH
855
856 /*
857 * Even though table entries have now been swapped, other CPU's
858 * may still be using the old entries. This is okay, because
859 * resynchronization happens because of the locking done
860 * during the get_counters() routine.
861 */
862 local_bh_enable();
863
fbabf31e
TG
864#ifdef CONFIG_AUDIT
865 if (audit_enabled) {
866 struct audit_buffer *ab;
867
868 ab = audit_log_start(current->audit_context, GFP_KERNEL,
869 AUDIT_NETFILTER_CFG);
870 if (ab) {
871 audit_log_format(ab, "table=%s family=%u entries=%u",
872 table->name, table->af,
873 private->number);
874 audit_log_end(ab);
875 }
876 }
877#endif
878
942e4a2b 879 return private;
2e4e6a17
HW
880}
881EXPORT_SYMBOL_GPL(xt_replace_table);
882
35aad0ff
JE
883struct xt_table *xt_register_table(struct net *net,
884 const struct xt_table *input_table,
a98da11d
AD
885 struct xt_table_info *bootstrap,
886 struct xt_table_info *newinfo)
2e4e6a17
HW
887{
888 int ret;
889 struct xt_table_info *private;
35aad0ff 890 struct xt_table *t, *table;
2e4e6a17 891
44d34e72 892 /* Don't add one object to multiple lists. */
35aad0ff 893 table = kmemdup(input_table, sizeof(struct xt_table), GFP_KERNEL);
44d34e72
AD
894 if (!table) {
895 ret = -ENOMEM;
896 goto out;
897 }
898
9e19bb6d 899 ret = mutex_lock_interruptible(&xt[table->af].mutex);
2e4e6a17 900 if (ret != 0)
44d34e72 901 goto out_free;
2e4e6a17
HW
902
903 /* Don't autoload: we'd eat our tail... */
8d870052 904 list_for_each_entry(t, &net->xt.tables[table->af], list) {
df0933dc
PM
905 if (strcmp(t->name, table->name) == 0) {
906 ret = -EEXIST;
907 goto unlock;
908 }
2e4e6a17
HW
909 }
910
911 /* Simplifies replace_table code. */
912 table->private = bootstrap;
78454473 913
2e4e6a17
HW
914 if (!xt_replace_table(table, 0, newinfo, &ret))
915 goto unlock;
916
917 private = table->private;
be91fd5e 918 pr_debug("table->private->number = %u\n", private->number);
2e4e6a17
HW
919
920 /* save number of initial entries */
921 private->initial_entries = private->number;
922
8d870052 923 list_add(&table->list, &net->xt.tables[table->af]);
a98da11d
AD
924 mutex_unlock(&xt[table->af].mutex);
925 return table;
2e4e6a17 926
2e4e6a17 927 unlock:
9e19bb6d 928 mutex_unlock(&xt[table->af].mutex);
44d34e72
AD
929out_free:
930 kfree(table);
a98da11d
AD
931out:
932 return ERR_PTR(ret);
2e4e6a17
HW
933}
934EXPORT_SYMBOL_GPL(xt_register_table);
935
936void *xt_unregister_table(struct xt_table *table)
937{
938 struct xt_table_info *private;
939
9e19bb6d 940 mutex_lock(&xt[table->af].mutex);
2e4e6a17 941 private = table->private;
df0933dc 942 list_del(&table->list);
9e19bb6d 943 mutex_unlock(&xt[table->af].mutex);
44d34e72 944 kfree(table);
2e4e6a17
HW
945
946 return private;
947}
948EXPORT_SYMBOL_GPL(xt_unregister_table);
949
950#ifdef CONFIG_PROC_FS
715cf35a
AD
951struct xt_names_priv {
952 struct seq_net_private p;
76108cea 953 u_int8_t af;
715cf35a 954};
025d93d1 955static void *xt_table_seq_start(struct seq_file *seq, loff_t *pos)
2e4e6a17 956{
715cf35a 957 struct xt_names_priv *priv = seq->private;
1218854a 958 struct net *net = seq_file_net(seq);
76108cea 959 u_int8_t af = priv->af;
2e4e6a17 960
025d93d1 961 mutex_lock(&xt[af].mutex);
715cf35a 962 return seq_list_start(&net->xt.tables[af], *pos);
025d93d1 963}
2e4e6a17 964
025d93d1
AD
965static void *xt_table_seq_next(struct seq_file *seq, void *v, loff_t *pos)
966{
715cf35a 967 struct xt_names_priv *priv = seq->private;
1218854a 968 struct net *net = seq_file_net(seq);
76108cea 969 u_int8_t af = priv->af;
2e4e6a17 970
715cf35a 971 return seq_list_next(v, &net->xt.tables[af], pos);
2e4e6a17
HW
972}
973
025d93d1 974static void xt_table_seq_stop(struct seq_file *seq, void *v)
2e4e6a17 975{
715cf35a 976 struct xt_names_priv *priv = seq->private;
76108cea 977 u_int8_t af = priv->af;
2e4e6a17 978
025d93d1
AD
979 mutex_unlock(&xt[af].mutex);
980}
2e4e6a17 981
025d93d1
AD
982static int xt_table_seq_show(struct seq_file *seq, void *v)
983{
984 struct xt_table *table = list_entry(v, struct xt_table, list);
2e4e6a17 985
025d93d1
AD
986 if (strlen(table->name))
987 return seq_printf(seq, "%s\n", table->name);
988 else
989 return 0;
990}
601e68e1 991
025d93d1
AD
992static const struct seq_operations xt_table_seq_ops = {
993 .start = xt_table_seq_start,
994 .next = xt_table_seq_next,
995 .stop = xt_table_seq_stop,
996 .show = xt_table_seq_show,
997};
998
999static int xt_table_open(struct inode *inode, struct file *file)
1000{
1001 int ret;
715cf35a 1002 struct xt_names_priv *priv;
025d93d1 1003
715cf35a
AD
1004 ret = seq_open_net(inode, file, &xt_table_seq_ops,
1005 sizeof(struct xt_names_priv));
025d93d1 1006 if (!ret) {
715cf35a 1007 priv = ((struct seq_file *)file->private_data)->private;
d9dda78b 1008 priv->af = (unsigned long)PDE_DATA(inode);
025d93d1
AD
1009 }
1010 return ret;
2e4e6a17
HW
1011}
1012
025d93d1
AD
1013static const struct file_operations xt_table_ops = {
1014 .owner = THIS_MODULE,
1015 .open = xt_table_open,
1016 .read = seq_read,
1017 .llseek = seq_lseek,
0e93bb94 1018 .release = seq_release_net,
025d93d1
AD
1019};
1020
eb132205
JE
1021/*
1022 * Traverse state for ip{,6}_{tables,matches} for helping crossing
1023 * the multi-AF mutexes.
1024 */
1025struct nf_mttg_trav {
1026 struct list_head *head, *curr;
1027 uint8_t class, nfproto;
1028};
1029
1030enum {
1031 MTTG_TRAV_INIT,
1032 MTTG_TRAV_NFP_UNSPEC,
1033 MTTG_TRAV_NFP_SPEC,
1034 MTTG_TRAV_DONE,
1035};
1036
1037static void *xt_mttg_seq_next(struct seq_file *seq, void *v, loff_t *ppos,
1038 bool is_target)
2e4e6a17 1039{
eb132205
JE
1040 static const uint8_t next_class[] = {
1041 [MTTG_TRAV_NFP_UNSPEC] = MTTG_TRAV_NFP_SPEC,
1042 [MTTG_TRAV_NFP_SPEC] = MTTG_TRAV_DONE,
1043 };
1044 struct nf_mttg_trav *trav = seq->private;
1045
1046 switch (trav->class) {
1047 case MTTG_TRAV_INIT:
1048 trav->class = MTTG_TRAV_NFP_UNSPEC;
1049 mutex_lock(&xt[NFPROTO_UNSPEC].mutex);
1050 trav->head = trav->curr = is_target ?
1051 &xt[NFPROTO_UNSPEC].target : &xt[NFPROTO_UNSPEC].match;
1052 break;
1053 case MTTG_TRAV_NFP_UNSPEC:
1054 trav->curr = trav->curr->next;
1055 if (trav->curr != trav->head)
1056 break;
1057 mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
1058 mutex_lock(&xt[trav->nfproto].mutex);
1059 trav->head = trav->curr = is_target ?
1060 &xt[trav->nfproto].target : &xt[trav->nfproto].match;
1061 trav->class = next_class[trav->class];
1062 break;
1063 case MTTG_TRAV_NFP_SPEC:
1064 trav->curr = trav->curr->next;
1065 if (trav->curr != trav->head)
1066 break;
1067 /* fallthru, _stop will unlock */
1068 default:
1069 return NULL;
1070 }
2e4e6a17 1071
eb132205
JE
1072 if (ppos != NULL)
1073 ++*ppos;
1074 return trav;
025d93d1 1075}
601e68e1 1076
eb132205
JE
1077static void *xt_mttg_seq_start(struct seq_file *seq, loff_t *pos,
1078 bool is_target)
025d93d1 1079{
eb132205
JE
1080 struct nf_mttg_trav *trav = seq->private;
1081 unsigned int j;
2e4e6a17 1082
eb132205
JE
1083 trav->class = MTTG_TRAV_INIT;
1084 for (j = 0; j < *pos; ++j)
1085 if (xt_mttg_seq_next(seq, NULL, NULL, is_target) == NULL)
1086 return NULL;
1087 return trav;
2e4e6a17
HW
1088}
1089
eb132205 1090static void xt_mttg_seq_stop(struct seq_file *seq, void *v)
2e4e6a17 1091{
eb132205
JE
1092 struct nf_mttg_trav *trav = seq->private;
1093
1094 switch (trav->class) {
1095 case MTTG_TRAV_NFP_UNSPEC:
1096 mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
1097 break;
1098 case MTTG_TRAV_NFP_SPEC:
1099 mutex_unlock(&xt[trav->nfproto].mutex);
1100 break;
1101 }
1102}
2e4e6a17 1103
eb132205
JE
1104static void *xt_match_seq_start(struct seq_file *seq, loff_t *pos)
1105{
1106 return xt_mttg_seq_start(seq, pos, false);
2e4e6a17
HW
1107}
1108
eb132205 1109static void *xt_match_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
2e4e6a17 1110{
eb132205
JE
1111 return xt_mttg_seq_next(seq, v, ppos, false);
1112}
2e4e6a17 1113
eb132205
JE
1114static int xt_match_seq_show(struct seq_file *seq, void *v)
1115{
1116 const struct nf_mttg_trav *trav = seq->private;
1117 const struct xt_match *match;
1118
1119 switch (trav->class) {
1120 case MTTG_TRAV_NFP_UNSPEC:
1121 case MTTG_TRAV_NFP_SPEC:
1122 if (trav->curr == trav->head)
1123 return 0;
1124 match = list_entry(trav->curr, struct xt_match, list);
1125 return (*match->name == '\0') ? 0 :
1126 seq_printf(seq, "%s\n", match->name);
1127 }
1128 return 0;
2e4e6a17
HW
1129}
1130
025d93d1
AD
1131static const struct seq_operations xt_match_seq_ops = {
1132 .start = xt_match_seq_start,
1133 .next = xt_match_seq_next,
eb132205 1134 .stop = xt_mttg_seq_stop,
025d93d1 1135 .show = xt_match_seq_show,
2e4e6a17
HW
1136};
1137
025d93d1 1138static int xt_match_open(struct inode *inode, struct file *file)
2e4e6a17 1139{
eb132205
JE
1140 struct seq_file *seq;
1141 struct nf_mttg_trav *trav;
2e4e6a17
HW
1142 int ret;
1143
eb132205
JE
1144 trav = kmalloc(sizeof(*trav), GFP_KERNEL);
1145 if (trav == NULL)
1146 return -ENOMEM;
2e4e6a17 1147
eb132205
JE
1148 ret = seq_open(file, &xt_match_seq_ops);
1149 if (ret < 0) {
1150 kfree(trav);
1151 return ret;
2e4e6a17 1152 }
eb132205
JE
1153
1154 seq = file->private_data;
1155 seq->private = trav;
d9dda78b 1156 trav->nfproto = (unsigned long)PDE_DATA(inode);
eb132205 1157 return 0;
025d93d1
AD
1158}
1159
1160static const struct file_operations xt_match_ops = {
1161 .owner = THIS_MODULE,
1162 .open = xt_match_open,
1163 .read = seq_read,
1164 .llseek = seq_lseek,
eb132205 1165 .release = seq_release_private,
025d93d1 1166};
2e4e6a17 1167
025d93d1
AD
1168static void *xt_target_seq_start(struct seq_file *seq, loff_t *pos)
1169{
eb132205 1170 return xt_mttg_seq_start(seq, pos, true);
025d93d1
AD
1171}
1172
eb132205 1173static void *xt_target_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
025d93d1 1174{
eb132205 1175 return xt_mttg_seq_next(seq, v, ppos, true);
025d93d1
AD
1176}
1177
1178static int xt_target_seq_show(struct seq_file *seq, void *v)
1179{
eb132205
JE
1180 const struct nf_mttg_trav *trav = seq->private;
1181 const struct xt_target *target;
1182
1183 switch (trav->class) {
1184 case MTTG_TRAV_NFP_UNSPEC:
1185 case MTTG_TRAV_NFP_SPEC:
1186 if (trav->curr == trav->head)
1187 return 0;
1188 target = list_entry(trav->curr, struct xt_target, list);
1189 return (*target->name == '\0') ? 0 :
1190 seq_printf(seq, "%s\n", target->name);
1191 }
1192 return 0;
025d93d1
AD
1193}
1194
1195static const struct seq_operations xt_target_seq_ops = {
1196 .start = xt_target_seq_start,
1197 .next = xt_target_seq_next,
eb132205 1198 .stop = xt_mttg_seq_stop,
025d93d1
AD
1199 .show = xt_target_seq_show,
1200};
1201
1202static int xt_target_open(struct inode *inode, struct file *file)
1203{
eb132205
JE
1204 struct seq_file *seq;
1205 struct nf_mttg_trav *trav;
025d93d1
AD
1206 int ret;
1207
eb132205
JE
1208 trav = kmalloc(sizeof(*trav), GFP_KERNEL);
1209 if (trav == NULL)
1210 return -ENOMEM;
025d93d1 1211
eb132205
JE
1212 ret = seq_open(file, &xt_target_seq_ops);
1213 if (ret < 0) {
1214 kfree(trav);
1215 return ret;
025d93d1 1216 }
eb132205
JE
1217
1218 seq = file->private_data;
1219 seq->private = trav;
d9dda78b 1220 trav->nfproto = (unsigned long)PDE_DATA(inode);
eb132205 1221 return 0;
2e4e6a17
HW
1222}
1223
025d93d1 1224static const struct file_operations xt_target_ops = {
2e4e6a17 1225 .owner = THIS_MODULE,
025d93d1 1226 .open = xt_target_open,
2e4e6a17
HW
1227 .read = seq_read,
1228 .llseek = seq_lseek,
eb132205 1229 .release = seq_release_private,
2e4e6a17
HW
1230};
1231
1232#define FORMAT_TABLES "_tables_names"
1233#define FORMAT_MATCHES "_tables_matches"
1234#define FORMAT_TARGETS "_tables_targets"
1235
1236#endif /* CONFIG_PROC_FS */
1237
2b95efe7
JE
1238/**
1239 * xt_hook_link - set up hooks for a new table
1240 * @table: table with metadata needed to set up hooks
1241 * @fn: Hook function
1242 *
1243 * This function will take care of creating and registering the necessary
1244 * Netfilter hooks for XT tables.
1245 */
1246struct nf_hook_ops *xt_hook_link(const struct xt_table *table, nf_hookfn *fn)
1247{
1248 unsigned int hook_mask = table->valid_hooks;
1249 uint8_t i, num_hooks = hweight32(hook_mask);
1250 uint8_t hooknum;
1251 struct nf_hook_ops *ops;
1252 int ret;
1253
1254 ops = kmalloc(sizeof(*ops) * num_hooks, GFP_KERNEL);
1255 if (ops == NULL)
1256 return ERR_PTR(-ENOMEM);
1257
1258 for (i = 0, hooknum = 0; i < num_hooks && hook_mask != 0;
1259 hook_mask >>= 1, ++hooknum) {
1260 if (!(hook_mask & 1))
1261 continue;
1262 ops[i].hook = fn;
1263 ops[i].owner = table->me;
1264 ops[i].pf = table->af;
1265 ops[i].hooknum = hooknum;
1266 ops[i].priority = table->priority;
1267 ++i;
1268 }
1269
1270 ret = nf_register_hooks(ops, num_hooks);
1271 if (ret < 0) {
1272 kfree(ops);
1273 return ERR_PTR(ret);
1274 }
1275
1276 return ops;
1277}
1278EXPORT_SYMBOL_GPL(xt_hook_link);
1279
1280/**
1281 * xt_hook_unlink - remove hooks for a table
1282 * @ops: nf_hook_ops array as returned by nf_hook_link
1283 * @hook_mask: the very same mask that was passed to nf_hook_link
1284 */
1285void xt_hook_unlink(const struct xt_table *table, struct nf_hook_ops *ops)
1286{
1287 nf_unregister_hooks(ops, hweight32(table->valid_hooks));
1288 kfree(ops);
1289}
1290EXPORT_SYMBOL_GPL(xt_hook_unlink);
1291
76108cea 1292int xt_proto_init(struct net *net, u_int8_t af)
2e4e6a17
HW
1293{
1294#ifdef CONFIG_PROC_FS
1295 char buf[XT_FUNCTION_MAXNAMELEN];
1296 struct proc_dir_entry *proc;
1297#endif
1298
7e9c6eeb 1299 if (af >= ARRAY_SIZE(xt_prefix))
2e4e6a17
HW
1300 return -EINVAL;
1301
1302
1303#ifdef CONFIG_PROC_FS
ce18afe5 1304 strlcpy(buf, xt_prefix[af], sizeof(buf));
2e4e6a17 1305 strlcat(buf, FORMAT_TABLES, sizeof(buf));
8b169240
DL
1306 proc = proc_create_data(buf, 0440, net->proc_net, &xt_table_ops,
1307 (void *)(unsigned long)af);
2e4e6a17
HW
1308 if (!proc)
1309 goto out;
2e4e6a17 1310
ce18afe5 1311 strlcpy(buf, xt_prefix[af], sizeof(buf));
2e4e6a17 1312 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
8b169240
DL
1313 proc = proc_create_data(buf, 0440, net->proc_net, &xt_match_ops,
1314 (void *)(unsigned long)af);
2e4e6a17
HW
1315 if (!proc)
1316 goto out_remove_tables;
2e4e6a17 1317
ce18afe5 1318 strlcpy(buf, xt_prefix[af], sizeof(buf));
2e4e6a17 1319 strlcat(buf, FORMAT_TARGETS, sizeof(buf));
8b169240
DL
1320 proc = proc_create_data(buf, 0440, net->proc_net, &xt_target_ops,
1321 (void *)(unsigned long)af);
2e4e6a17
HW
1322 if (!proc)
1323 goto out_remove_matches;
2e4e6a17
HW
1324#endif
1325
1326 return 0;
1327
1328#ifdef CONFIG_PROC_FS
1329out_remove_matches:
ce18afe5 1330 strlcpy(buf, xt_prefix[af], sizeof(buf));
2e4e6a17 1331 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
ece31ffd 1332 remove_proc_entry(buf, net->proc_net);
2e4e6a17
HW
1333
1334out_remove_tables:
ce18afe5 1335 strlcpy(buf, xt_prefix[af], sizeof(buf));
2e4e6a17 1336 strlcat(buf, FORMAT_TABLES, sizeof(buf));
ece31ffd 1337 remove_proc_entry(buf, net->proc_net);
2e4e6a17
HW
1338out:
1339 return -1;
1340#endif
1341}
1342EXPORT_SYMBOL_GPL(xt_proto_init);
1343
76108cea 1344void xt_proto_fini(struct net *net, u_int8_t af)
2e4e6a17
HW
1345{
1346#ifdef CONFIG_PROC_FS
1347 char buf[XT_FUNCTION_MAXNAMELEN];
1348
ce18afe5 1349 strlcpy(buf, xt_prefix[af], sizeof(buf));
2e4e6a17 1350 strlcat(buf, FORMAT_TABLES, sizeof(buf));
ece31ffd 1351 remove_proc_entry(buf, net->proc_net);
2e4e6a17 1352
ce18afe5 1353 strlcpy(buf, xt_prefix[af], sizeof(buf));
2e4e6a17 1354 strlcat(buf, FORMAT_TARGETS, sizeof(buf));
ece31ffd 1355 remove_proc_entry(buf, net->proc_net);
2e4e6a17 1356
ce18afe5 1357 strlcpy(buf, xt_prefix[af], sizeof(buf));
2e4e6a17 1358 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
ece31ffd 1359 remove_proc_entry(buf, net->proc_net);
2e4e6a17
HW
1360#endif /*CONFIG_PROC_FS*/
1361}
1362EXPORT_SYMBOL_GPL(xt_proto_fini);
1363
8d870052
AD
1364static int __net_init xt_net_init(struct net *net)
1365{
1366 int i;
1367
7e9c6eeb 1368 for (i = 0; i < NFPROTO_NUMPROTO; i++)
8d870052
AD
1369 INIT_LIST_HEAD(&net->xt.tables[i]);
1370 return 0;
1371}
1372
1373static struct pernet_operations xt_net_ops = {
1374 .init = xt_net_init,
1375};
2e4e6a17
HW
1376
1377static int __init xt_init(void)
1378{
942e4a2b
SH
1379 unsigned int i;
1380 int rv;
1381
1382 for_each_possible_cpu(i) {
7f5c6d4f 1383 seqcount_init(&per_cpu(xt_recseq, i));
942e4a2b 1384 }
2e4e6a17 1385
7e9c6eeb 1386 xt = kmalloc(sizeof(struct xt_af) * NFPROTO_NUMPROTO, GFP_KERNEL);
2e4e6a17
HW
1387 if (!xt)
1388 return -ENOMEM;
1389
7e9c6eeb 1390 for (i = 0; i < NFPROTO_NUMPROTO; i++) {
9e19bb6d 1391 mutex_init(&xt[i].mutex);
2722971c
DM
1392#ifdef CONFIG_COMPAT
1393 mutex_init(&xt[i].compat_mutex);
255d0dc3 1394 xt[i].compat_tab = NULL;
2722971c 1395#endif
2e4e6a17
HW
1396 INIT_LIST_HEAD(&xt[i].target);
1397 INIT_LIST_HEAD(&xt[i].match);
2e4e6a17 1398 }
8d870052
AD
1399 rv = register_pernet_subsys(&xt_net_ops);
1400 if (rv < 0)
1401 kfree(xt);
1402 return rv;
2e4e6a17
HW
1403}
1404
1405static void __exit xt_fini(void)
1406{
8d870052 1407 unregister_pernet_subsys(&xt_net_ops);
2e4e6a17
HW
1408 kfree(xt);
1409}
1410
1411module_init(xt_init);
1412module_exit(xt_fini);
1413
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