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16#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17#include <linux/kernel.h>
18#include <linux/module.h>
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>
25#include <linux/mutex.h>
26#include <linux/mm.h>
27#include <linux/slab.h>
28#include <linux/audit.h>
29#include <net/net_namespace.h>
30
31#include <linux/netfilter/x_tables.h>
32#include <linux/netfilter_arp.h>
33#include <linux/netfilter_ipv4/ip_tables.h>
34#include <linux/netfilter_ipv6/ip6_tables.h>
35#include <linux/netfilter_arp/arp_tables.h>
36
37MODULE_LICENSE("GPL");
38MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
39MODULE_DESCRIPTION("{ip,ip6,arp,eb}_tables backend module");
40
41#define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1))
42
43struct compat_delta {
44 unsigned int offset;
45 int delta;
46};
47
48struct xt_af {
49 struct mutex mutex;
50 struct list_head match;
51 struct list_head target;
52#ifdef CONFIG_COMPAT
53 struct mutex compat_mutex;
54 struct compat_delta *compat_tab;
55 unsigned int number;
56 unsigned int cur;
57#endif
58};
59
60static struct xt_af *xt;
61
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",
68};
69
70
71static const unsigned int xt_jumpstack_multiplier = 2;
72
73
74int
75xt_register_target(struct xt_target *target)
76{
77 u_int8_t af = target->family;
78 int ret;
79
80 ret = mutex_lock_interruptible(&xt[af].mutex);
81 if (ret != 0)
82 return ret;
83 list_add(&target->list, &xt[af].target);
84 mutex_unlock(&xt[af].mutex);
85 return ret;
86}
87EXPORT_SYMBOL(xt_register_target);
88
89void
90xt_unregister_target(struct xt_target *target)
91{
92 u_int8_t af = target->family;
93
94 mutex_lock(&xt[af].mutex);
95 list_del(&target->list);
96 mutex_unlock(&xt[af].mutex);
97}
98EXPORT_SYMBOL(xt_unregister_target);
99
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{
123 while (n-- > 0)
124 xt_unregister_target(&target[n]);
125}
126EXPORT_SYMBOL(xt_unregister_targets);
127
128int
129xt_register_match(struct xt_match *match)
130{
131 u_int8_t af = match->family;
132 int ret;
133
134 ret = mutex_lock_interruptible(&xt[af].mutex);
135 if (ret != 0)
136 return ret;
137
138 list_add(&match->list, &xt[af].match);
139 mutex_unlock(&xt[af].mutex);
140
141 return ret;
142}
143EXPORT_SYMBOL(xt_register_match);
144
145void
146xt_unregister_match(struct xt_match *match)
147{
148 u_int8_t af = match->family;
149
150 mutex_lock(&xt[af].mutex);
151 list_del(&match->list);
152 mutex_unlock(&xt[af].mutex);
153}
154EXPORT_SYMBOL(xt_unregister_match);
155
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{
179 while (n-- > 0)
180 xt_unregister_match(&match[n]);
181}
182EXPORT_SYMBOL(xt_unregister_matches);
183
184
185
186
187
188
189
190
191
192struct xt_match *xt_find_match(u8 af, const char *name, u8 revision)
193{
194 struct xt_match *m;
195 int err = -ENOENT;
196
197 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
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)) {
204 mutex_unlock(&xt[af].mutex);
205 return m;
206 }
207 } else
208 err = -EPROTOTYPE;
209 }
210 }
211 mutex_unlock(&xt[af].mutex);
212
213 if (af != NFPROTO_UNSPEC)
214
215 return xt_find_match(NFPROTO_UNSPEC, name, revision);
216
217 return ERR_PTR(err);
218}
219EXPORT_SYMBOL(xt_find_match);
220
221struct xt_match *
222xt_request_find_match(uint8_t nfproto, const char *name, uint8_t revision)
223{
224 struct xt_match *match;
225
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;
233}
234EXPORT_SYMBOL_GPL(xt_request_find_match);
235
236
237struct xt_target *xt_find_target(u8 af, const char *name, u8 revision)
238{
239 struct xt_target *t;
240 int err = -ENOENT;
241
242 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
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)) {
249 mutex_unlock(&xt[af].mutex);
250 return t;
251 }
252 } else
253 err = -EPROTOTYPE;
254 }
255 }
256 mutex_unlock(&xt[af].mutex);
257
258 if (af != NFPROTO_UNSPEC)
259
260 return xt_find_target(NFPROTO_UNSPEC, name, revision);
261
262 return ERR_PTR(err);
263}
264EXPORT_SYMBOL(xt_find_target);
265
266struct xt_target *xt_request_find_target(u8 af, const char *name, u8 revision)
267{
268 struct xt_target *target;
269
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;
277}
278EXPORT_SYMBOL_GPL(xt_request_find_target);
279
280static int match_revfn(u8 af, const char *name, u8 revision, int *bestp)
281{
282 const struct xt_match *m;
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 }
293
294 if (af != NFPROTO_UNSPEC && !have_rev)
295 return match_revfn(NFPROTO_UNSPEC, name, revision, bestp);
296
297 return have_rev;
298}
299
300static int target_revfn(u8 af, const char *name, u8 revision, int *bestp)
301{
302 const struct xt_target *t;
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 }
313
314 if (af != NFPROTO_UNSPEC && !have_rev)
315 return target_revfn(NFPROTO_UNSPEC, name, revision, bestp);
316
317 return have_rev;
318}
319
320
321int xt_find_revision(u8 af, const char *name, u8 revision, int target,
322 int *err)
323{
324 int have_rev, best = -1;
325
326 if (mutex_lock_interruptible(&xt[af].mutex) != 0) {
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);
334 mutex_unlock(&xt[af].mutex);
335
336
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
349static char *
350textify_hooks(char *buf, size_t size, unsigned int mask, uint8_t nfproto)
351{
352 static const char *const inetbr_names[] = {
353 "PREROUTING", "INPUT", "FORWARD",
354 "OUTPUT", "POSTROUTING", "BROUTING",
355 };
356 static const char *const arp_names[] = {
357 "INPUT", "FORWARD", "OUTPUT",
358 };
359 const char *const *names;
360 unsigned int i, max;
361 char *p = buf;
362 bool np = false;
363 int res;
364
365 names = (nfproto == NFPROTO_ARP) ? arp_names : inetbr_names;
366 max = (nfproto == NFPROTO_ARP) ? ARRAY_SIZE(arp_names) :
367 ARRAY_SIZE(inetbr_names);
368 *p = '\0';
369 for (i = 0; i < max; ++i) {
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
383int xt_check_match(struct xt_mtchk_param *par,
384 unsigned int size, u_int8_t proto, bool inv_proto)
385{
386 int ret;
387
388 if (XT_ALIGN(par->match->matchsize) != size &&
389 par->match->matchsize != -1) {
390
391
392
393
394 pr_err("%s_tables: %s.%u match: invalid size "
395 "%u (kernel) != (user) %u\n",
396 xt_prefix[par->family], par->match->name,
397 par->match->revision,
398 XT_ALIGN(par->match->matchsize), size);
399 return -EINVAL;
400 }
401 if (par->match->table != NULL &&
402 strcmp(par->match->table, par->table) != 0) {
403 pr_err("%s_tables: %s match: only valid in %s table, not %s\n",
404 xt_prefix[par->family], par->match->name,
405 par->match->table, par->table);
406 return -EINVAL;
407 }
408 if (par->match->hooks && (par->hook_mask & ~par->match->hooks) != 0) {
409 char used[64], allow[64];
410
411 pr_err("%s_tables: %s match: used from hooks %s, but only "
412 "valid from %s\n",
413 xt_prefix[par->family], par->match->name,
414 textify_hooks(used, sizeof(used), par->hook_mask,
415 par->family),
416 textify_hooks(allow, sizeof(allow), par->match->hooks,
417 par->family));
418 return -EINVAL;
419 }
420 if (par->match->proto && (par->match->proto != proto || inv_proto)) {
421 pr_err("%s_tables: %s match: only valid for protocol %u\n",
422 xt_prefix[par->family], par->match->name,
423 par->match->proto);
424 return -EINVAL;
425 }
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
432 return -EIO;
433 }
434 return 0;
435}
436EXPORT_SYMBOL_GPL(xt_check_match);
437
438#ifdef CONFIG_COMPAT
439int xt_compat_add_offset(u_int8_t af, unsigned int offset, int delta)
440{
441 struct xt_af *xp = &xt[af];
442
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 }
451
452 if (xp->cur >= xp->number)
453 return -EINVAL;
454
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++;
460 return 0;
461}
462EXPORT_SYMBOL_GPL(xt_compat_add_offset);
463
464void xt_compat_flush_offsets(u_int8_t af)
465{
466 if (xt[af].compat_tab) {
467 vfree(xt[af].compat_tab);
468 xt[af].compat_tab = NULL;
469 xt[af].number = 0;
470 xt[af].cur = 0;
471 }
472}
473EXPORT_SYMBOL_GPL(xt_compat_flush_offsets);
474
475int xt_compat_calc_jump(u_int8_t af, unsigned int offset)
476{
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 }
489 return left ? tmp[left - 1].delta : 0;
490}
491EXPORT_SYMBOL_GPL(xt_compat_calc_jump);
492
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
500int xt_compat_match_offset(const struct xt_match *match)
501{
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
507int xt_compat_match_from_user(struct xt_entry_match *m, void **dstptr,
508 unsigned int *size)
509{
510 const struct xt_match *match = m->u.kernel.match;
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;
530 return 0;
531}
532EXPORT_SYMBOL_GPL(xt_compat_match_from_user);
533
534int xt_compat_match_to_user(const struct xt_entry_match *m,
535 void __user **dstptr, unsigned int *size)
536{
537 const struct xt_match *match = m->u.kernel.match;
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)) ||
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))
546 return -EFAULT;
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;
554 }
555
556 *size -= off;
557 *dstptr += msize;
558 return 0;
559}
560EXPORT_SYMBOL_GPL(xt_compat_match_to_user);
561#endif
562
563int xt_check_target(struct xt_tgchk_param *par,
564 unsigned int size, u_int8_t proto, bool inv_proto)
565{
566 int ret;
567
568 if (XT_ALIGN(par->target->targetsize) != size) {
569 pr_err("%s_tables: %s.%u target: invalid size "
570 "%u (kernel) != (user) %u\n",
571 xt_prefix[par->family], par->target->name,
572 par->target->revision,
573 XT_ALIGN(par->target->targetsize), size);
574 return -EINVAL;
575 }
576 if (par->target->table != NULL &&
577 strcmp(par->target->table, par->table) != 0) {
578 pr_err("%s_tables: %s target: only valid in %s table, not %s\n",
579 xt_prefix[par->family], par->target->name,
580 par->target->table, par->table);
581 return -EINVAL;
582 }
583 if (par->target->hooks && (par->hook_mask & ~par->target->hooks) != 0) {
584 char used[64], allow[64];
585
586 pr_err("%s_tables: %s target: used from hooks %s, but only "
587 "usable from %s\n",
588 xt_prefix[par->family], par->target->name,
589 textify_hooks(used, sizeof(used), par->hook_mask,
590 par->family),
591 textify_hooks(allow, sizeof(allow), par->target->hooks,
592 par->family));
593 return -EINVAL;
594 }
595 if (par->target->proto && (par->target->proto != proto || inv_proto)) {
596 pr_err("%s_tables: %s target: only valid for protocol %u\n",
597 xt_prefix[par->family], par->target->name,
598 par->target->proto);
599 return -EINVAL;
600 }
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
607 return -EIO;
608 }
609 return 0;
610}
611EXPORT_SYMBOL_GPL(xt_check_target);
612
613#ifdef CONFIG_COMPAT
614int xt_compat_target_offset(const struct xt_target *target)
615{
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,
622 unsigned int *size)
623{
624 const struct xt_target *target = t->u.kernel.target;
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
647int xt_compat_target_to_user(const struct xt_entry_target *t,
648 void __user **dstptr, unsigned int *size)
649{
650 const struct xt_target *target = t->u.kernel.target;
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)) ||
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))
659 return -EFAULT;
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;
667 }
668
669 *size -= off;
670 *dstptr += tsize;
671 return 0;
672}
673EXPORT_SYMBOL_GPL(xt_compat_target_to_user);
674#endif
675
676struct xt_table_info *xt_alloc_table_info(unsigned int size)
677{
678 struct xt_table_info *newinfo;
679 int cpu;
680
681
682 if ((SMP_ALIGN(size) >> PAGE_SHIFT) + 2 > totalram_pages)
683 return NULL;
684
685 newinfo = kzalloc(XT_TABLE_INFO_SZ, GFP_KERNEL);
686 if (!newinfo)
687 return NULL;
688
689 newinfo->size = size;
690
691 for_each_possible_cpu(cpu) {
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
714 for_each_possible_cpu(cpu) {
715 if (info->size <= PAGE_SIZE)
716 kfree(info->entries[cpu]);
717 else
718 vfree(info->entries[cpu]);
719 }
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);
735
736 free_percpu(info->stackptr);
737
738 kfree(info);
739}
740EXPORT_SYMBOL(xt_free_table_info);
741
742
743struct xt_table *xt_find_table_lock(struct net *net, u_int8_t af,
744 const char *name)
745{
746 struct xt_table *t;
747
748 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
749 return ERR_PTR(-EINTR);
750
751 list_for_each_entry(t, &net->xt.tables[af], list)
752 if (strcmp(t->name, name) == 0 && try_module_get(t->me))
753 return t;
754 mutex_unlock(&xt[af].mutex);
755 return NULL;
756}
757EXPORT_SYMBOL_GPL(xt_find_table_lock);
758
759void xt_table_unlock(struct xt_table *table)
760{
761 mutex_unlock(&xt[table->af].mutex);
762}
763EXPORT_SYMBOL_GPL(xt_table_unlock);
764
765#ifdef CONFIG_COMPAT
766void xt_compat_lock(u_int8_t af)
767{
768 mutex_lock(&xt[af].compat_mutex);
769}
770EXPORT_SYMBOL_GPL(xt_compat_lock);
771
772void xt_compat_unlock(u_int8_t af)
773{
774 mutex_unlock(&xt[af].compat_mutex);
775}
776EXPORT_SYMBOL_GPL(xt_compat_unlock);
777#endif
778
779DEFINE_PER_CPU(seqcount_t, xt_recseq);
780EXPORT_PER_CPU_SYMBOL_GPL(xt_recseq);
781
782static int xt_jumpstack_alloc(struct xt_table_info *i)
783{
784 unsigned int size;
785 int cpu;
786
787 i->stackptr = alloc_percpu(unsigned int);
788 if (i->stackptr == NULL)
789 return -ENOMEM;
790
791 size = sizeof(void **) * nr_cpu_ids;
792 if (size > PAGE_SIZE)
793 i->jumpstack = vzalloc(size);
794 else
795 i->jumpstack = kzalloc(size, GFP_KERNEL);
796 if (i->jumpstack == NULL)
797 return -ENOMEM;
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
811
812
813
814 return -ENOMEM;
815 }
816
817 return 0;
818}
819
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{
826 struct xt_table_info *private;
827 int ret;
828
829 ret = xt_jumpstack_alloc(newinfo);
830 if (ret < 0) {
831 *error = ret;
832 return NULL;
833 }
834
835
836 local_bh_disable();
837 private = table->private;
838
839
840 if (num_counters != private->number) {
841 pr_debug("num_counters != table->private->number (%u/%u)\n",
842 num_counters, private->number);
843 local_bh_enable();
844 *error = -EAGAIN;
845 return NULL;
846 }
847
848 table->private = newinfo;
849 newinfo->initial_entries = private->initial_entries;
850
851
852
853
854
855
856
857 local_bh_enable();
858
859#ifdef CONFIG_AUDIT
860 if (audit_enabled) {
861 struct audit_buffer *ab;
862
863 ab = audit_log_start(current->audit_context, GFP_KERNEL,
864 AUDIT_NETFILTER_CFG);
865 if (ab) {
866 audit_log_format(ab, "table=%s family=%u entries=%u",
867 table->name, table->af,
868 private->number);
869 audit_log_end(ab);
870 }
871 }
872#endif
873
874 return private;
875}
876EXPORT_SYMBOL_GPL(xt_replace_table);
877
878struct xt_table *xt_register_table(struct net *net,
879 const struct xt_table *input_table,
880 struct xt_table_info *bootstrap,
881 struct xt_table_info *newinfo)
882{
883 int ret;
884 struct xt_table_info *private;
885 struct xt_table *t, *table;
886
887
888 table = kmemdup(input_table, sizeof(struct xt_table), GFP_KERNEL);
889 if (!table) {
890 ret = -ENOMEM;
891 goto out;
892 }
893
894 ret = mutex_lock_interruptible(&xt[table->af].mutex);
895 if (ret != 0)
896 goto out_free;
897
898
899 list_for_each_entry(t, &net->xt.tables[table->af], list) {
900 if (strcmp(t->name, table->name) == 0) {
901 ret = -EEXIST;
902 goto unlock;
903 }
904 }
905
906
907 table->private = bootstrap;
908
909 if (!xt_replace_table(table, 0, newinfo, &ret))
910 goto unlock;
911
912 private = table->private;
913 pr_debug("table->private->number = %u\n", private->number);
914
915
916 private->initial_entries = private->number;
917
918 list_add(&table->list, &net->xt.tables[table->af]);
919 mutex_unlock(&xt[table->af].mutex);
920 return table;
921
922 unlock:
923 mutex_unlock(&xt[table->af].mutex);
924out_free:
925 kfree(table);
926out:
927 return ERR_PTR(ret);
928}
929EXPORT_SYMBOL_GPL(xt_register_table);
930
931void *xt_unregister_table(struct xt_table *table)
932{
933 struct xt_table_info *private;
934
935 mutex_lock(&xt[table->af].mutex);
936 private = table->private;
937 list_del(&table->list);
938 mutex_unlock(&xt[table->af].mutex);
939 kfree(table);
940
941 return private;
942}
943EXPORT_SYMBOL_GPL(xt_unregister_table);
944
945#ifdef CONFIG_PROC_FS
946struct xt_names_priv {
947 struct seq_net_private p;
948 u_int8_t af;
949};
950static void *xt_table_seq_start(struct seq_file *seq, loff_t *pos)
951{
952 struct xt_names_priv *priv = seq->private;
953 struct net *net = seq_file_net(seq);
954 u_int8_t af = priv->af;
955
956 mutex_lock(&xt[af].mutex);
957 return seq_list_start(&net->xt.tables[af], *pos);
958}
959
960static void *xt_table_seq_next(struct seq_file *seq, void *v, loff_t *pos)
961{
962 struct xt_names_priv *priv = seq->private;
963 struct net *net = seq_file_net(seq);
964 u_int8_t af = priv->af;
965
966 return seq_list_next(v, &net->xt.tables[af], pos);
967}
968
969static void xt_table_seq_stop(struct seq_file *seq, void *v)
970{
971 struct xt_names_priv *priv = seq->private;
972 u_int8_t af = priv->af;
973
974 mutex_unlock(&xt[af].mutex);
975}
976
977static int xt_table_seq_show(struct seq_file *seq, void *v)
978{
979 struct xt_table *table = list_entry(v, struct xt_table, list);
980
981 if (strlen(table->name))
982 return seq_printf(seq, "%s\n", table->name);
983 else
984 return 0;
985}
986
987static const struct seq_operations xt_table_seq_ops = {
988 .start = xt_table_seq_start,
989 .next = xt_table_seq_next,
990 .stop = xt_table_seq_stop,
991 .show = xt_table_seq_show,
992};
993
994static int xt_table_open(struct inode *inode, struct file *file)
995{
996 int ret;
997 struct xt_names_priv *priv;
998
999 ret = seq_open_net(inode, file, &xt_table_seq_ops,
1000 sizeof(struct xt_names_priv));
1001 if (!ret) {
1002 priv = ((struct seq_file *)file->private_data)->private;
1003 priv->af = (unsigned long)PDE_DATA(inode);
1004 }
1005 return ret;
1006}
1007
1008static const struct file_operations xt_table_ops = {
1009 .owner = THIS_MODULE,
1010 .open = xt_table_open,
1011 .read = seq_read,
1012 .llseek = seq_lseek,
1013 .release = seq_release_net,
1014};
1015
1016
1017
1018
1019
1020struct nf_mttg_trav {
1021 struct list_head *head, *curr;
1022 uint8_t class, nfproto;
1023};
1024
1025enum {
1026 MTTG_TRAV_INIT,
1027 MTTG_TRAV_NFP_UNSPEC,
1028 MTTG_TRAV_NFP_SPEC,
1029 MTTG_TRAV_DONE,
1030};
1031
1032static void *xt_mttg_seq_next(struct seq_file *seq, void *v, loff_t *ppos,
1033 bool is_target)
1034{
1035 static const uint8_t next_class[] = {
1036 [MTTG_TRAV_NFP_UNSPEC] = MTTG_TRAV_NFP_SPEC,
1037 [MTTG_TRAV_NFP_SPEC] = MTTG_TRAV_DONE,
1038 };
1039 struct nf_mttg_trav *trav = seq->private;
1040
1041 switch (trav->class) {
1042 case MTTG_TRAV_INIT:
1043 trav->class = MTTG_TRAV_NFP_UNSPEC;
1044 mutex_lock(&xt[NFPROTO_UNSPEC].mutex);
1045 trav->head = trav->curr = is_target ?
1046 &xt[NFPROTO_UNSPEC].target : &xt[NFPROTO_UNSPEC].match;
1047 break;
1048 case MTTG_TRAV_NFP_UNSPEC:
1049 trav->curr = trav->curr->next;
1050 if (trav->curr != trav->head)
1051 break;
1052 mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
1053 mutex_lock(&xt[trav->nfproto].mutex);
1054 trav->head = trav->curr = is_target ?
1055 &xt[trav->nfproto].target : &xt[trav->nfproto].match;
1056 trav->class = next_class[trav->class];
1057 break;
1058 case MTTG_TRAV_NFP_SPEC:
1059 trav->curr = trav->curr->next;
1060 if (trav->curr != trav->head)
1061 break;
1062
1063 default:
1064 return NULL;
1065 }
1066
1067 if (ppos != NULL)
1068 ++*ppos;
1069 return trav;
1070}
1071
1072static void *xt_mttg_seq_start(struct seq_file *seq, loff_t *pos,
1073 bool is_target)
1074{
1075 struct nf_mttg_trav *trav = seq->private;
1076 unsigned int j;
1077
1078 trav->class = MTTG_TRAV_INIT;
1079 for (j = 0; j < *pos; ++j)
1080 if (xt_mttg_seq_next(seq, NULL, NULL, is_target) == NULL)
1081 return NULL;
1082 return trav;
1083}
1084
1085static void xt_mttg_seq_stop(struct seq_file *seq, void *v)
1086{
1087 struct nf_mttg_trav *trav = seq->private;
1088
1089 switch (trav->class) {
1090 case MTTG_TRAV_NFP_UNSPEC:
1091 mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
1092 break;
1093 case MTTG_TRAV_NFP_SPEC:
1094 mutex_unlock(&xt[trav->nfproto].mutex);
1095 break;
1096 }
1097}
1098
1099static void *xt_match_seq_start(struct seq_file *seq, loff_t *pos)
1100{
1101 return xt_mttg_seq_start(seq, pos, false);
1102}
1103
1104static void *xt_match_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
1105{
1106 return xt_mttg_seq_next(seq, v, ppos, false);
1107}
1108
1109static int xt_match_seq_show(struct seq_file *seq, void *v)
1110{
1111 const struct nf_mttg_trav *trav = seq->private;
1112 const struct xt_match *match;
1113
1114 switch (trav->class) {
1115 case MTTG_TRAV_NFP_UNSPEC:
1116 case MTTG_TRAV_NFP_SPEC:
1117 if (trav->curr == trav->head)
1118 return 0;
1119 match = list_entry(trav->curr, struct xt_match, list);
1120 return (*match->name == '\0') ? 0 :
1121 seq_printf(seq, "%s\n", match->name);
1122 }
1123 return 0;
1124}
1125
1126static const struct seq_operations xt_match_seq_ops = {
1127 .start = xt_match_seq_start,
1128 .next = xt_match_seq_next,
1129 .stop = xt_mttg_seq_stop,
1130 .show = xt_match_seq_show,
1131};
1132
1133static int xt_match_open(struct inode *inode, struct file *file)
1134{
1135 struct seq_file *seq;
1136 struct nf_mttg_trav *trav;
1137 int ret;
1138
1139 trav = kmalloc(sizeof(*trav), GFP_KERNEL);
1140 if (trav == NULL)
1141 return -ENOMEM;
1142
1143 ret = seq_open(file, &xt_match_seq_ops);
1144 if (ret < 0) {
1145 kfree(trav);
1146 return ret;
1147 }
1148
1149 seq = file->private_data;
1150 seq->private = trav;
1151 trav->nfproto = (unsigned long)PDE_DATA(inode);
1152 return 0;
1153}
1154
1155static const struct file_operations xt_match_ops = {
1156 .owner = THIS_MODULE,
1157 .open = xt_match_open,
1158 .read = seq_read,
1159 .llseek = seq_lseek,
1160 .release = seq_release_private,
1161};
1162
1163static void *xt_target_seq_start(struct seq_file *seq, loff_t *pos)
1164{
1165 return xt_mttg_seq_start(seq, pos, true);
1166}
1167
1168static void *xt_target_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
1169{
1170 return xt_mttg_seq_next(seq, v, ppos, true);
1171}
1172
1173static int xt_target_seq_show(struct seq_file *seq, void *v)
1174{
1175 const struct nf_mttg_trav *trav = seq->private;
1176 const struct xt_target *target;
1177
1178 switch (trav->class) {
1179 case MTTG_TRAV_NFP_UNSPEC:
1180 case MTTG_TRAV_NFP_SPEC:
1181 if (trav->curr == trav->head)
1182 return 0;
1183 target = list_entry(trav->curr, struct xt_target, list);
1184 return (*target->name == '\0') ? 0 :
1185 seq_printf(seq, "%s\n", target->name);
1186 }
1187 return 0;
1188}
1189
1190static const struct seq_operations xt_target_seq_ops = {
1191 .start = xt_target_seq_start,
1192 .next = xt_target_seq_next,
1193 .stop = xt_mttg_seq_stop,
1194 .show = xt_target_seq_show,
1195};
1196
1197static int xt_target_open(struct inode *inode, struct file *file)
1198{
1199 struct seq_file *seq;
1200 struct nf_mttg_trav *trav;
1201 int ret;
1202
1203 trav = kmalloc(sizeof(*trav), GFP_KERNEL);
1204 if (trav == NULL)
1205 return -ENOMEM;
1206
1207 ret = seq_open(file, &xt_target_seq_ops);
1208 if (ret < 0) {
1209 kfree(trav);
1210 return ret;
1211 }
1212
1213 seq = file->private_data;
1214 seq->private = trav;
1215 trav->nfproto = (unsigned long)PDE_DATA(inode);
1216 return 0;
1217}
1218
1219static const struct file_operations xt_target_ops = {
1220 .owner = THIS_MODULE,
1221 .open = xt_target_open,
1222 .read = seq_read,
1223 .llseek = seq_lseek,
1224 .release = seq_release_private,
1225};
1226
1227#define FORMAT_TABLES "_tables_names"
1228#define FORMAT_MATCHES "_tables_matches"
1229#define FORMAT_TARGETS "_tables_targets"
1230
1231#endif
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241struct nf_hook_ops *xt_hook_link(const struct xt_table *table, nf_hookfn *fn)
1242{
1243 unsigned int hook_mask = table->valid_hooks;
1244 uint8_t i, num_hooks = hweight32(hook_mask);
1245 uint8_t hooknum;
1246 struct nf_hook_ops *ops;
1247 int ret;
1248
1249 ops = kmalloc(sizeof(*ops) * num_hooks, GFP_KERNEL);
1250 if (ops == NULL)
1251 return ERR_PTR(-ENOMEM);
1252
1253 for (i = 0, hooknum = 0; i < num_hooks && hook_mask != 0;
1254 hook_mask >>= 1, ++hooknum) {
1255 if (!(hook_mask & 1))
1256 continue;
1257 ops[i].hook = fn;
1258 ops[i].owner = table->me;
1259 ops[i].pf = table->af;
1260 ops[i].hooknum = hooknum;
1261 ops[i].priority = table->priority;
1262 ++i;
1263 }
1264
1265 ret = nf_register_hooks(ops, num_hooks);
1266 if (ret < 0) {
1267 kfree(ops);
1268 return ERR_PTR(ret);
1269 }
1270
1271 return ops;
1272}
1273EXPORT_SYMBOL_GPL(xt_hook_link);
1274
1275
1276
1277
1278
1279
1280void xt_hook_unlink(const struct xt_table *table, struct nf_hook_ops *ops)
1281{
1282 nf_unregister_hooks(ops, hweight32(table->valid_hooks));
1283 kfree(ops);
1284}
1285EXPORT_SYMBOL_GPL(xt_hook_unlink);
1286
1287int xt_proto_init(struct net *net, u_int8_t af)
1288{
1289#ifdef CONFIG_PROC_FS
1290 char buf[XT_FUNCTION_MAXNAMELEN];
1291 struct proc_dir_entry *proc;
1292#endif
1293
1294 if (af >= ARRAY_SIZE(xt_prefix))
1295 return -EINVAL;
1296
1297
1298#ifdef CONFIG_PROC_FS
1299 strlcpy(buf, xt_prefix[af], sizeof(buf));
1300 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1301 proc = proc_create_data(buf, 0440, net->proc_net, &xt_table_ops,
1302 (void *)(unsigned long)af);
1303 if (!proc)
1304 goto out;
1305
1306 strlcpy(buf, xt_prefix[af], sizeof(buf));
1307 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1308 proc = proc_create_data(buf, 0440, net->proc_net, &xt_match_ops,
1309 (void *)(unsigned long)af);
1310 if (!proc)
1311 goto out_remove_tables;
1312
1313 strlcpy(buf, xt_prefix[af], sizeof(buf));
1314 strlcat(buf, FORMAT_TARGETS, sizeof(buf));
1315 proc = proc_create_data(buf, 0440, net->proc_net, &xt_target_ops,
1316 (void *)(unsigned long)af);
1317 if (!proc)
1318 goto out_remove_matches;
1319#endif
1320
1321 return 0;
1322
1323#ifdef CONFIG_PROC_FS
1324out_remove_matches:
1325 strlcpy(buf, xt_prefix[af], sizeof(buf));
1326 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1327 remove_proc_entry(buf, net->proc_net);
1328
1329out_remove_tables:
1330 strlcpy(buf, xt_prefix[af], sizeof(buf));
1331 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1332 remove_proc_entry(buf, net->proc_net);
1333out:
1334 return -1;
1335#endif
1336}
1337EXPORT_SYMBOL_GPL(xt_proto_init);
1338
1339void xt_proto_fini(struct net *net, u_int8_t af)
1340{
1341#ifdef CONFIG_PROC_FS
1342 char buf[XT_FUNCTION_MAXNAMELEN];
1343
1344 strlcpy(buf, xt_prefix[af], sizeof(buf));
1345 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1346 remove_proc_entry(buf, net->proc_net);
1347
1348 strlcpy(buf, xt_prefix[af], sizeof(buf));
1349 strlcat(buf, FORMAT_TARGETS, sizeof(buf));
1350 remove_proc_entry(buf, net->proc_net);
1351
1352 strlcpy(buf, xt_prefix[af], sizeof(buf));
1353 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1354 remove_proc_entry(buf, net->proc_net);
1355#endif
1356}
1357EXPORT_SYMBOL_GPL(xt_proto_fini);
1358
1359static int __net_init xt_net_init(struct net *net)
1360{
1361 int i;
1362
1363 for (i = 0; i < NFPROTO_NUMPROTO; i++)
1364 INIT_LIST_HEAD(&net->xt.tables[i]);
1365 return 0;
1366}
1367
1368static struct pernet_operations xt_net_ops = {
1369 .init = xt_net_init,
1370};
1371
1372static int __init xt_init(void)
1373{
1374 unsigned int i;
1375 int rv;
1376
1377 for_each_possible_cpu(i) {
1378 seqcount_init(&per_cpu(xt_recseq, i));
1379 }
1380
1381 xt = kmalloc(sizeof(struct xt_af) * NFPROTO_NUMPROTO, GFP_KERNEL);
1382 if (!xt)
1383 return -ENOMEM;
1384
1385 for (i = 0; i < NFPROTO_NUMPROTO; i++) {
1386 mutex_init(&xt[i].mutex);
1387#ifdef CONFIG_COMPAT
1388 mutex_init(&xt[i].compat_mutex);
1389 xt[i].compat_tab = NULL;
1390#endif
1391 INIT_LIST_HEAD(&xt[i].target);
1392 INIT_LIST_HEAD(&xt[i].match);
1393 }
1394 rv = register_pernet_subsys(&xt_net_ops);
1395 if (rv < 0)
1396 kfree(xt);
1397 return rv;
1398}
1399
1400static void __exit xt_fini(void)
1401{
1402 unregister_pernet_subsys(&xt_net_ops);
1403 kfree(xt);
1404}
1405
1406module_init(xt_init);
1407module_exit(xt_fini);
1408
1409