2 * x_tables core - Backend for {ip,ip6,arp}_tables
4 * Copyright (C) 2006-2006 Harald Welte <laforge@netfilter.org>
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>
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.
15 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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>
23 #include <linux/mutex.h>
25 #include <linux/slab.h>
26 #include <linux/audit.h>
27 #include <net/net_namespace.h>
29 #include <linux/netfilter/x_tables.h>
30 #include <linux/netfilter_arp.h>
31 #include <linux/netfilter_ipv4/ip_tables.h>
32 #include <linux/netfilter_ipv6/ip6_tables.h>
33 #include <linux/netfilter_arp/arp_tables.h>
35 MODULE_LICENSE("GPL");
36 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
37 MODULE_DESCRIPTION("{ip,ip6,arp,eb}_tables backend module");
39 #define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1))
42 unsigned int offset; /* offset in kernel */
43 int delta; /* delta in 32bit user land */
48 struct list_head match;
49 struct list_head target;
51 struct mutex compat_mutex;
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[] */
58 static struct xt_af *xt;
60 static 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",
68 /* Allow this many total (re)entries. */
69 static const unsigned int xt_jumpstack_multiplier = 2;
71 /* Registration hooks for targets. */
73 xt_register_target(struct xt_target *target)
75 u_int8_t af = target->family;
78 ret = mutex_lock_interruptible(&xt[af].mutex);
81 list_add(&target->list, &xt[af].target);
82 mutex_unlock(&xt[af].mutex);
85 EXPORT_SYMBOL(xt_register_target);
88 xt_unregister_target(struct xt_target *target)
90 u_int8_t af = target->family;
92 mutex_lock(&xt[af].mutex);
93 list_del(&target->list);
94 mutex_unlock(&xt[af].mutex);
96 EXPORT_SYMBOL(xt_unregister_target);
99 xt_register_targets(struct xt_target *target, unsigned int n)
104 for (i = 0; i < n; i++) {
105 err = xt_register_target(&target[i]);
113 xt_unregister_targets(target, i);
116 EXPORT_SYMBOL(xt_register_targets);
119 xt_unregister_targets(struct xt_target *target, unsigned int n)
122 xt_unregister_target(&target[n]);
124 EXPORT_SYMBOL(xt_unregister_targets);
127 xt_register_match(struct xt_match *match)
129 u_int8_t af = match->family;
132 ret = mutex_lock_interruptible(&xt[af].mutex);
136 list_add(&match->list, &xt[af].match);
137 mutex_unlock(&xt[af].mutex);
141 EXPORT_SYMBOL(xt_register_match);
144 xt_unregister_match(struct xt_match *match)
146 u_int8_t af = match->family;
148 mutex_lock(&xt[af].mutex);
149 list_del(&match->list);
150 mutex_unlock(&xt[af].mutex);
152 EXPORT_SYMBOL(xt_unregister_match);
155 xt_register_matches(struct xt_match *match, unsigned int n)
160 for (i = 0; i < n; i++) {
161 err = xt_register_match(&match[i]);
169 xt_unregister_matches(match, i);
172 EXPORT_SYMBOL(xt_register_matches);
175 xt_unregister_matches(struct xt_match *match, unsigned int n)
178 xt_unregister_match(&match[n]);
180 EXPORT_SYMBOL(xt_unregister_matches);
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
189 /* Find match, grabs ref. Returns ERR_PTR() on error. */
190 struct xt_match *xt_find_match(u8 af, const char *name, u8 revision)
195 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
196 return ERR_PTR(-EINTR);
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)) {
202 mutex_unlock(&xt[af].mutex);
206 err = -EPROTOTYPE; /* Found something. */
209 mutex_unlock(&xt[af].mutex);
211 if (af != NFPROTO_UNSPEC)
212 /* Try searching again in the family-independent list */
213 return xt_find_match(NFPROTO_UNSPEC, name, revision);
217 EXPORT_SYMBOL(xt_find_match);
220 xt_request_find_match(uint8_t nfproto, const char *name, uint8_t revision)
222 struct xt_match *match;
224 match = xt_find_match(nfproto, name, revision);
226 request_module("%st_%s", xt_prefix[nfproto], name);
227 match = xt_find_match(nfproto, name, revision);
232 EXPORT_SYMBOL_GPL(xt_request_find_match);
234 /* Find target, grabs ref. Returns ERR_PTR() on error. */
235 struct xt_target *xt_find_target(u8 af, const char *name, u8 revision)
240 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
241 return ERR_PTR(-EINTR);
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)) {
247 mutex_unlock(&xt[af].mutex);
251 err = -EPROTOTYPE; /* Found something. */
254 mutex_unlock(&xt[af].mutex);
256 if (af != NFPROTO_UNSPEC)
257 /* Try searching again in the family-independent list */
258 return xt_find_target(NFPROTO_UNSPEC, name, revision);
262 EXPORT_SYMBOL(xt_find_target);
264 struct xt_target *xt_request_find_target(u8 af, const char *name, u8 revision)
266 struct xt_target *target;
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);
276 EXPORT_SYMBOL_GPL(xt_request_find_target);
278 static int match_revfn(u8 af, const char *name, u8 revision, int *bestp)
280 const struct xt_match *m;
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)
292 if (af != NFPROTO_UNSPEC && !have_rev)
293 return match_revfn(NFPROTO_UNSPEC, name, revision, bestp);
298 static int target_revfn(u8 af, const char *name, u8 revision, int *bestp)
300 const struct xt_target *t;
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)
312 if (af != NFPROTO_UNSPEC && !have_rev)
313 return target_revfn(NFPROTO_UNSPEC, name, revision, bestp);
318 /* Returns true or false (if no such extension at all) */
319 int xt_find_revision(u8 af, const char *name, u8 revision, int target,
322 int have_rev, best = -1;
324 if (mutex_lock_interruptible(&xt[af].mutex) != 0) {
329 have_rev = target_revfn(af, name, revision, &best);
331 have_rev = match_revfn(af, name, revision, &best);
332 mutex_unlock(&xt[af].mutex);
334 /* Nothing at all? Return 0 to try loading module. */
342 *err = -EPROTONOSUPPORT;
345 EXPORT_SYMBOL_GPL(xt_find_revision);
347 static char *textify_hooks(char *buf, size_t size, unsigned int mask)
349 static const char *const names[] = {
350 "PREROUTING", "INPUT", "FORWARD",
351 "OUTPUT", "POSTROUTING", "BROUTING",
359 for (i = 0; i < ARRAY_SIZE(names); ++i) {
360 if (!(mask & (1 << i)))
362 res = snprintf(p, size, "%s%s", np ? "/" : "", names[i]);
373 int xt_check_match(struct xt_mtchk_param *par,
374 unsigned int size, u_int8_t proto, bool inv_proto)
378 if (XT_ALIGN(par->match->matchsize) != size &&
379 par->match->matchsize != -1) {
381 * ebt_among is exempt from centralized matchsize checking
382 * because it uses a dynamic-size data set.
384 pr_err("%s_tables: %s.%u match: invalid size "
385 "%u (kernel) != (user) %u\n",
386 xt_prefix[par->family], par->match->name,
387 par->match->revision,
388 XT_ALIGN(par->match->matchsize), size);
391 if (par->match->table != NULL &&
392 strcmp(par->match->table, par->table) != 0) {
393 pr_err("%s_tables: %s match: only valid in %s table, not %s\n",
394 xt_prefix[par->family], par->match->name,
395 par->match->table, par->table);
398 if (par->match->hooks && (par->hook_mask & ~par->match->hooks) != 0) {
399 char used[64], allow[64];
401 pr_err("%s_tables: %s match: used from hooks %s, but only "
403 xt_prefix[par->family], par->match->name,
404 textify_hooks(used, sizeof(used), par->hook_mask),
405 textify_hooks(allow, sizeof(allow), par->match->hooks));
408 if (par->match->proto && (par->match->proto != proto || inv_proto)) {
409 pr_err("%s_tables: %s match: only valid for protocol %u\n",
410 xt_prefix[par->family], par->match->name,
414 if (par->match->checkentry != NULL) {
415 ret = par->match->checkentry(par);
419 /* Flag up potential errors. */
424 EXPORT_SYMBOL_GPL(xt_check_match);
427 int xt_compat_add_offset(u_int8_t af, unsigned int offset, int delta)
429 struct xt_af *xp = &xt[af];
431 if (!xp->compat_tab) {
434 xp->compat_tab = vmalloc(sizeof(struct compat_delta) * xp->number);
440 if (xp->cur >= xp->number)
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;
450 EXPORT_SYMBOL_GPL(xt_compat_add_offset);
452 void xt_compat_flush_offsets(u_int8_t af)
454 if (xt[af].compat_tab) {
455 vfree(xt[af].compat_tab);
456 xt[af].compat_tab = NULL;
461 EXPORT_SYMBOL_GPL(xt_compat_flush_offsets);
463 int xt_compat_calc_jump(u_int8_t af, unsigned int offset)
465 struct compat_delta *tmp = xt[af].compat_tab;
466 int mid, left = 0, right = xt[af].cur - 1;
468 while (left <= right) {
469 mid = (left + right) >> 1;
470 if (offset > tmp[mid].offset)
472 else if (offset < tmp[mid].offset)
475 return mid ? tmp[mid - 1].delta : 0;
477 return left ? tmp[left - 1].delta : 0;
479 EXPORT_SYMBOL_GPL(xt_compat_calc_jump);
481 void xt_compat_init_offsets(u_int8_t af, unsigned int number)
483 xt[af].number = number;
486 EXPORT_SYMBOL(xt_compat_init_offsets);
488 int xt_compat_match_offset(const struct xt_match *match)
490 u_int16_t csize = match->compatsize ? : match->matchsize;
491 return XT_ALIGN(match->matchsize) - COMPAT_XT_ALIGN(csize);
493 EXPORT_SYMBOL_GPL(xt_compat_match_offset);
495 int xt_compat_match_from_user(struct xt_entry_match *m, void **dstptr,
498 const struct xt_match *match = m->u.kernel.match;
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;
504 memcpy(m, cm, sizeof(*cm));
505 if (match->compat_from_user)
506 match->compat_from_user(m->data, cm->data);
508 memcpy(m->data, cm->data, msize - sizeof(*cm));
509 pad = XT_ALIGN(match->matchsize) - match->matchsize;
511 memset(m->data + match->matchsize, 0, pad);
514 m->u.user.match_size = msize;
520 EXPORT_SYMBOL_GPL(xt_compat_match_from_user);
522 int xt_compat_match_to_user(const struct xt_entry_match *m,
523 void __user **dstptr, unsigned int *size)
525 const struct xt_match *match = m->u.kernel.match;
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;
530 if (copy_to_user(cm, m, sizeof(*cm)) ||
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))
536 if (match->compat_to_user) {
537 if (match->compat_to_user((void __user *)cm->data, m->data))
540 if (copy_to_user(cm->data, m->data, msize - sizeof(*cm)))
548 EXPORT_SYMBOL_GPL(xt_compat_match_to_user);
549 #endif /* CONFIG_COMPAT */
551 int xt_check_target(struct xt_tgchk_param *par,
552 unsigned int size, u_int8_t proto, bool inv_proto)
556 if (XT_ALIGN(par->target->targetsize) != size) {
557 pr_err("%s_tables: %s.%u target: invalid size "
558 "%u (kernel) != (user) %u\n",
559 xt_prefix[par->family], par->target->name,
560 par->target->revision,
561 XT_ALIGN(par->target->targetsize), size);
564 if (par->target->table != NULL &&
565 strcmp(par->target->table, par->table) != 0) {
566 pr_err("%s_tables: %s target: only valid in %s table, not %s\n",
567 xt_prefix[par->family], par->target->name,
568 par->target->table, par->table);
571 if (par->target->hooks && (par->hook_mask & ~par->target->hooks) != 0) {
572 char used[64], allow[64];
574 pr_err("%s_tables: %s target: used from hooks %s, but only "
576 xt_prefix[par->family], par->target->name,
577 textify_hooks(used, sizeof(used), par->hook_mask),
578 textify_hooks(allow, sizeof(allow), par->target->hooks));
581 if (par->target->proto && (par->target->proto != proto || inv_proto)) {
582 pr_err("%s_tables: %s target: only valid for protocol %u\n",
583 xt_prefix[par->family], par->target->name,
587 if (par->target->checkentry != NULL) {
588 ret = par->target->checkentry(par);
592 /* Flag up potential errors. */
597 EXPORT_SYMBOL_GPL(xt_check_target);
600 int xt_compat_target_offset(const struct xt_target *target)
602 u_int16_t csize = target->compatsize ? : target->targetsize;
603 return XT_ALIGN(target->targetsize) - COMPAT_XT_ALIGN(csize);
605 EXPORT_SYMBOL_GPL(xt_compat_target_offset);
607 void xt_compat_target_from_user(struct xt_entry_target *t, void **dstptr,
610 const struct xt_target *target = t->u.kernel.target;
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;
616 memcpy(t, ct, sizeof(*ct));
617 if (target->compat_from_user)
618 target->compat_from_user(t->data, ct->data);
620 memcpy(t->data, ct->data, tsize - sizeof(*ct));
621 pad = XT_ALIGN(target->targetsize) - target->targetsize;
623 memset(t->data + target->targetsize, 0, pad);
626 t->u.user.target_size = tsize;
631 EXPORT_SYMBOL_GPL(xt_compat_target_from_user);
633 int xt_compat_target_to_user(const struct xt_entry_target *t,
634 void __user **dstptr, unsigned int *size)
636 const struct xt_target *target = t->u.kernel.target;
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;
641 if (copy_to_user(ct, t, sizeof(*ct)) ||
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))
647 if (target->compat_to_user) {
648 if (target->compat_to_user((void __user *)ct->data, t->data))
651 if (copy_to_user(ct->data, t->data, tsize - sizeof(*ct)))
659 EXPORT_SYMBOL_GPL(xt_compat_target_to_user);
662 struct xt_table_info *xt_alloc_table_info(unsigned int size)
664 struct xt_table_info *newinfo;
667 /* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */
668 if ((SMP_ALIGN(size) >> PAGE_SHIFT) + 2 > totalram_pages)
671 newinfo = kzalloc(XT_TABLE_INFO_SZ, GFP_KERNEL);
675 newinfo->size = size;
677 for_each_possible_cpu(cpu) {
678 if (size <= PAGE_SIZE)
679 newinfo->entries[cpu] = kmalloc_node(size,
683 newinfo->entries[cpu] = vmalloc_node(size,
686 if (newinfo->entries[cpu] == NULL) {
687 xt_free_table_info(newinfo);
694 EXPORT_SYMBOL(xt_alloc_table_info);
696 void xt_free_table_info(struct xt_table_info *info)
700 for_each_possible_cpu(cpu) {
701 if (info->size <= PAGE_SIZE)
702 kfree(info->entries[cpu]);
704 vfree(info->entries[cpu]);
707 if (info->jumpstack != NULL) {
708 if (sizeof(void *) * info->stacksize > PAGE_SIZE) {
709 for_each_possible_cpu(cpu)
710 vfree(info->jumpstack[cpu]);
712 for_each_possible_cpu(cpu)
713 kfree(info->jumpstack[cpu]);
717 if (sizeof(void **) * nr_cpu_ids > PAGE_SIZE)
718 vfree(info->jumpstack);
720 kfree(info->jumpstack);
722 free_percpu(info->stackptr);
726 EXPORT_SYMBOL(xt_free_table_info);
728 /* Find table by name, grabs mutex & ref. Returns ERR_PTR() on error. */
729 struct xt_table *xt_find_table_lock(struct net *net, u_int8_t af,
734 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
735 return ERR_PTR(-EINTR);
737 list_for_each_entry(t, &net->xt.tables[af], list)
738 if (strcmp(t->name, name) == 0 && try_module_get(t->me))
740 mutex_unlock(&xt[af].mutex);
743 EXPORT_SYMBOL_GPL(xt_find_table_lock);
745 void xt_table_unlock(struct xt_table *table)
747 mutex_unlock(&xt[table->af].mutex);
749 EXPORT_SYMBOL_GPL(xt_table_unlock);
752 void xt_compat_lock(u_int8_t af)
754 mutex_lock(&xt[af].compat_mutex);
756 EXPORT_SYMBOL_GPL(xt_compat_lock);
758 void xt_compat_unlock(u_int8_t af)
760 mutex_unlock(&xt[af].compat_mutex);
762 EXPORT_SYMBOL_GPL(xt_compat_unlock);
765 DEFINE_PER_CPU(struct xt_info_lock, xt_info_locks);
766 EXPORT_PER_CPU_SYMBOL_GPL(xt_info_locks);
768 static int xt_jumpstack_alloc(struct xt_table_info *i)
773 i->stackptr = alloc_percpu(unsigned int);
774 if (i->stackptr == NULL)
777 size = sizeof(void **) * nr_cpu_ids;
778 if (size > PAGE_SIZE)
779 i->jumpstack = vmalloc(size);
781 i->jumpstack = kmalloc(size, GFP_KERNEL);
782 if (i->jumpstack == NULL)
784 memset(i->jumpstack, 0, size);
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,
793 i->jumpstack[cpu] = kmalloc_node(size,
794 GFP_KERNEL, cpu_to_node(cpu));
795 if (i->jumpstack[cpu] == NULL)
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.
807 struct xt_table_info *
808 xt_replace_table(struct xt_table *table,
809 unsigned int num_counters,
810 struct xt_table_info *newinfo,
813 struct xt_table_info *private;
816 ret = xt_jumpstack_alloc(newinfo);
822 /* Do the substitution. */
824 private = table->private;
826 /* Check inside lock: is the old number correct? */
827 if (num_counters != private->number) {
828 pr_debug("num_counters != table->private->number (%u/%u)\n",
829 num_counters, private->number);
835 table->private = newinfo;
836 newinfo->initial_entries = private->initial_entries;
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.
848 struct audit_buffer *ab;
850 ab = audit_log_start(current->audit_context, GFP_KERNEL,
851 AUDIT_NETFILTER_CFG);
853 audit_log_format(ab, "table=%s family=%u entries=%u",
854 table->name, table->af,
863 EXPORT_SYMBOL_GPL(xt_replace_table);
865 struct xt_table *xt_register_table(struct net *net,
866 const struct xt_table *input_table,
867 struct xt_table_info *bootstrap,
868 struct xt_table_info *newinfo)
871 struct xt_table_info *private;
872 struct xt_table *t, *table;
874 /* Don't add one object to multiple lists. */
875 table = kmemdup(input_table, sizeof(struct xt_table), GFP_KERNEL);
881 ret = mutex_lock_interruptible(&xt[table->af].mutex);
885 /* Don't autoload: we'd eat our tail... */
886 list_for_each_entry(t, &net->xt.tables[table->af], list) {
887 if (strcmp(t->name, table->name) == 0) {
893 /* Simplifies replace_table code. */
894 table->private = bootstrap;
896 if (!xt_replace_table(table, 0, newinfo, &ret))
899 private = table->private;
900 pr_debug("table->private->number = %u\n", private->number);
902 /* save number of initial entries */
903 private->initial_entries = private->number;
905 list_add(&table->list, &net->xt.tables[table->af]);
906 mutex_unlock(&xt[table->af].mutex);
910 mutex_unlock(&xt[table->af].mutex);
916 EXPORT_SYMBOL_GPL(xt_register_table);
918 void *xt_unregister_table(struct xt_table *table)
920 struct xt_table_info *private;
922 mutex_lock(&xt[table->af].mutex);
923 private = table->private;
924 list_del(&table->list);
925 mutex_unlock(&xt[table->af].mutex);
930 EXPORT_SYMBOL_GPL(xt_unregister_table);
932 #ifdef CONFIG_PROC_FS
933 struct xt_names_priv {
934 struct seq_net_private p;
937 static void *xt_table_seq_start(struct seq_file *seq, loff_t *pos)
939 struct xt_names_priv *priv = seq->private;
940 struct net *net = seq_file_net(seq);
941 u_int8_t af = priv->af;
943 mutex_lock(&xt[af].mutex);
944 return seq_list_start(&net->xt.tables[af], *pos);
947 static void *xt_table_seq_next(struct seq_file *seq, void *v, loff_t *pos)
949 struct xt_names_priv *priv = seq->private;
950 struct net *net = seq_file_net(seq);
951 u_int8_t af = priv->af;
953 return seq_list_next(v, &net->xt.tables[af], pos);
956 static void xt_table_seq_stop(struct seq_file *seq, void *v)
958 struct xt_names_priv *priv = seq->private;
959 u_int8_t af = priv->af;
961 mutex_unlock(&xt[af].mutex);
964 static int xt_table_seq_show(struct seq_file *seq, void *v)
966 struct xt_table *table = list_entry(v, struct xt_table, list);
968 if (strlen(table->name))
969 return seq_printf(seq, "%s\n", table->name);
974 static 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,
981 static int xt_table_open(struct inode *inode, struct file *file)
984 struct xt_names_priv *priv;
986 ret = seq_open_net(inode, file, &xt_table_seq_ops,
987 sizeof(struct xt_names_priv));
989 priv = ((struct seq_file *)file->private_data)->private;
990 priv->af = (unsigned long)PDE(inode)->data;
995 static const struct file_operations xt_table_ops = {
996 .owner = THIS_MODULE,
997 .open = xt_table_open,
1000 .release = seq_release_net,
1004 * Traverse state for ip{,6}_{tables,matches} for helping crossing
1005 * the multi-AF mutexes.
1007 struct nf_mttg_trav {
1008 struct list_head *head, *curr;
1009 uint8_t class, nfproto;
1014 MTTG_TRAV_NFP_UNSPEC,
1019 static void *xt_mttg_seq_next(struct seq_file *seq, void *v, loff_t *ppos,
1022 static const uint8_t next_class[] = {
1023 [MTTG_TRAV_NFP_UNSPEC] = MTTG_TRAV_NFP_SPEC,
1024 [MTTG_TRAV_NFP_SPEC] = MTTG_TRAV_DONE,
1026 struct nf_mttg_trav *trav = seq->private;
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;
1035 case MTTG_TRAV_NFP_UNSPEC:
1036 trav->curr = trav->curr->next;
1037 if (trav->curr != trav->head)
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];
1045 case MTTG_TRAV_NFP_SPEC:
1046 trav->curr = trav->curr->next;
1047 if (trav->curr != trav->head)
1049 /* fallthru, _stop will unlock */
1059 static void *xt_mttg_seq_start(struct seq_file *seq, loff_t *pos,
1062 struct nf_mttg_trav *trav = seq->private;
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)
1072 static void xt_mttg_seq_stop(struct seq_file *seq, void *v)
1074 struct nf_mttg_trav *trav = seq->private;
1076 switch (trav->class) {
1077 case MTTG_TRAV_NFP_UNSPEC:
1078 mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
1080 case MTTG_TRAV_NFP_SPEC:
1081 mutex_unlock(&xt[trav->nfproto].mutex);
1086 static void *xt_match_seq_start(struct seq_file *seq, loff_t *pos)
1088 return xt_mttg_seq_start(seq, pos, false);
1091 static void *xt_match_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
1093 return xt_mttg_seq_next(seq, v, ppos, false);
1096 static int xt_match_seq_show(struct seq_file *seq, void *v)
1098 const struct nf_mttg_trav *trav = seq->private;
1099 const struct xt_match *match;
1101 switch (trav->class) {
1102 case MTTG_TRAV_NFP_UNSPEC:
1103 case MTTG_TRAV_NFP_SPEC:
1104 if (trav->curr == trav->head)
1106 match = list_entry(trav->curr, struct xt_match, list);
1107 return (*match->name == '\0') ? 0 :
1108 seq_printf(seq, "%s\n", match->name);
1113 static const struct seq_operations xt_match_seq_ops = {
1114 .start = xt_match_seq_start,
1115 .next = xt_match_seq_next,
1116 .stop = xt_mttg_seq_stop,
1117 .show = xt_match_seq_show,
1120 static int xt_match_open(struct inode *inode, struct file *file)
1122 struct seq_file *seq;
1123 struct nf_mttg_trav *trav;
1126 trav = kmalloc(sizeof(*trav), GFP_KERNEL);
1130 ret = seq_open(file, &xt_match_seq_ops);
1136 seq = file->private_data;
1137 seq->private = trav;
1138 trav->nfproto = (unsigned long)PDE(inode)->data;
1142 static const struct file_operations xt_match_ops = {
1143 .owner = THIS_MODULE,
1144 .open = xt_match_open,
1146 .llseek = seq_lseek,
1147 .release = seq_release_private,
1150 static void *xt_target_seq_start(struct seq_file *seq, loff_t *pos)
1152 return xt_mttg_seq_start(seq, pos, true);
1155 static void *xt_target_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
1157 return xt_mttg_seq_next(seq, v, ppos, true);
1160 static int xt_target_seq_show(struct seq_file *seq, void *v)
1162 const struct nf_mttg_trav *trav = seq->private;
1163 const struct xt_target *target;
1165 switch (trav->class) {
1166 case MTTG_TRAV_NFP_UNSPEC:
1167 case MTTG_TRAV_NFP_SPEC:
1168 if (trav->curr == trav->head)
1170 target = list_entry(trav->curr, struct xt_target, list);
1171 return (*target->name == '\0') ? 0 :
1172 seq_printf(seq, "%s\n", target->name);
1177 static const struct seq_operations xt_target_seq_ops = {
1178 .start = xt_target_seq_start,
1179 .next = xt_target_seq_next,
1180 .stop = xt_mttg_seq_stop,
1181 .show = xt_target_seq_show,
1184 static int xt_target_open(struct inode *inode, struct file *file)
1186 struct seq_file *seq;
1187 struct nf_mttg_trav *trav;
1190 trav = kmalloc(sizeof(*trav), GFP_KERNEL);
1194 ret = seq_open(file, &xt_target_seq_ops);
1200 seq = file->private_data;
1201 seq->private = trav;
1202 trav->nfproto = (unsigned long)PDE(inode)->data;
1206 static const struct file_operations xt_target_ops = {
1207 .owner = THIS_MODULE,
1208 .open = xt_target_open,
1210 .llseek = seq_lseek,
1211 .release = seq_release_private,
1214 #define FORMAT_TABLES "_tables_names"
1215 #define FORMAT_MATCHES "_tables_matches"
1216 #define FORMAT_TARGETS "_tables_targets"
1218 #endif /* CONFIG_PROC_FS */
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
1225 * This function will take care of creating and registering the necessary
1226 * Netfilter hooks for XT tables.
1228 struct nf_hook_ops *xt_hook_link(const struct xt_table *table, nf_hookfn *fn)
1230 unsigned int hook_mask = table->valid_hooks;
1231 uint8_t i, num_hooks = hweight32(hook_mask);
1233 struct nf_hook_ops *ops;
1236 ops = kmalloc(sizeof(*ops) * num_hooks, GFP_KERNEL);
1238 return ERR_PTR(-ENOMEM);
1240 for (i = 0, hooknum = 0; i < num_hooks && hook_mask != 0;
1241 hook_mask >>= 1, ++hooknum) {
1242 if (!(hook_mask & 1))
1245 ops[i].owner = table->me;
1246 ops[i].pf = table->af;
1247 ops[i].hooknum = hooknum;
1248 ops[i].priority = table->priority;
1252 ret = nf_register_hooks(ops, num_hooks);
1255 return ERR_PTR(ret);
1260 EXPORT_SYMBOL_GPL(xt_hook_link);
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
1267 void xt_hook_unlink(const struct xt_table *table, struct nf_hook_ops *ops)
1269 nf_unregister_hooks(ops, hweight32(table->valid_hooks));
1272 EXPORT_SYMBOL_GPL(xt_hook_unlink);
1274 int xt_proto_init(struct net *net, u_int8_t af)
1276 #ifdef CONFIG_PROC_FS
1277 char buf[XT_FUNCTION_MAXNAMELEN];
1278 struct proc_dir_entry *proc;
1281 if (af >= ARRAY_SIZE(xt_prefix))
1285 #ifdef CONFIG_PROC_FS
1286 strlcpy(buf, xt_prefix[af], sizeof(buf));
1287 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1288 proc = proc_create_data(buf, 0440, net->proc_net, &xt_table_ops,
1289 (void *)(unsigned long)af);
1293 strlcpy(buf, xt_prefix[af], sizeof(buf));
1294 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1295 proc = proc_create_data(buf, 0440, net->proc_net, &xt_match_ops,
1296 (void *)(unsigned long)af);
1298 goto out_remove_tables;
1300 strlcpy(buf, xt_prefix[af], sizeof(buf));
1301 strlcat(buf, FORMAT_TARGETS, sizeof(buf));
1302 proc = proc_create_data(buf, 0440, net->proc_net, &xt_target_ops,
1303 (void *)(unsigned long)af);
1305 goto out_remove_matches;
1310 #ifdef CONFIG_PROC_FS
1312 strlcpy(buf, xt_prefix[af], sizeof(buf));
1313 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1314 proc_net_remove(net, buf);
1317 strlcpy(buf, xt_prefix[af], sizeof(buf));
1318 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1319 proc_net_remove(net, buf);
1324 EXPORT_SYMBOL_GPL(xt_proto_init);
1326 void xt_proto_fini(struct net *net, u_int8_t af)
1328 #ifdef CONFIG_PROC_FS
1329 char buf[XT_FUNCTION_MAXNAMELEN];
1331 strlcpy(buf, xt_prefix[af], sizeof(buf));
1332 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1333 proc_net_remove(net, buf);
1335 strlcpy(buf, xt_prefix[af], sizeof(buf));
1336 strlcat(buf, FORMAT_TARGETS, sizeof(buf));
1337 proc_net_remove(net, buf);
1339 strlcpy(buf, xt_prefix[af], sizeof(buf));
1340 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1341 proc_net_remove(net, buf);
1342 #endif /*CONFIG_PROC_FS*/
1344 EXPORT_SYMBOL_GPL(xt_proto_fini);
1346 static int __net_init xt_net_init(struct net *net)
1350 for (i = 0; i < NFPROTO_NUMPROTO; i++)
1351 INIT_LIST_HEAD(&net->xt.tables[i]);
1355 static struct pernet_operations xt_net_ops = {
1356 .init = xt_net_init,
1359 static int __init xt_init(void)
1364 for_each_possible_cpu(i) {
1365 struct xt_info_lock *lock = &per_cpu(xt_info_locks, i);
1367 seqlock_init(&lock->lock);
1371 xt = kmalloc(sizeof(struct xt_af) * NFPROTO_NUMPROTO, GFP_KERNEL);
1375 for (i = 0; i < NFPROTO_NUMPROTO; i++) {
1376 mutex_init(&xt[i].mutex);
1377 #ifdef CONFIG_COMPAT
1378 mutex_init(&xt[i].compat_mutex);
1379 xt[i].compat_tab = NULL;
1381 INIT_LIST_HEAD(&xt[i].target);
1382 INIT_LIST_HEAD(&xt[i].match);
1384 rv = register_pernet_subsys(&xt_net_ops);
1390 static void __exit xt_fini(void)
1392 unregister_pernet_subsys(&xt_net_ops);
1396 module_init(xt_init);
1397 module_exit(xt_fini);