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 <net/net_namespace.h>
27 #include <linux/netfilter/x_tables.h>
28 #include <linux/netfilter_arp.h>
29 #include <linux/netfilter_ipv4/ip_tables.h>
30 #include <linux/netfilter_ipv6/ip6_tables.h>
31 #include <linux/netfilter_arp/arp_tables.h>
33 MODULE_LICENSE("GPL");
34 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
35 MODULE_DESCRIPTION("{ip,ip6,arp,eb}_tables backend module");
37 #define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1))
40 struct compat_delta *next;
47 struct list_head match;
48 struct list_head target;
50 struct mutex compat_mutex;
51 struct compat_delta *compat_offsets;
55 static struct xt_af *xt;
57 static const char *const xt_prefix[NFPROTO_NUMPROTO] = {
58 [NFPROTO_UNSPEC] = "x",
59 [NFPROTO_IPV4] = "ip",
60 [NFPROTO_ARP] = "arp",
61 [NFPROTO_BRIDGE] = "eb",
62 [NFPROTO_IPV6] = "ip6",
65 /* Registration hooks for targets. */
67 xt_register_target(struct xt_target *target)
69 u_int8_t af = target->family;
72 ret = mutex_lock_interruptible(&xt[af].mutex);
75 list_add(&target->list, &xt[af].target);
76 mutex_unlock(&xt[af].mutex);
79 EXPORT_SYMBOL(xt_register_target);
82 xt_unregister_target(struct xt_target *target)
84 u_int8_t af = target->family;
86 mutex_lock(&xt[af].mutex);
87 list_del(&target->list);
88 mutex_unlock(&xt[af].mutex);
90 EXPORT_SYMBOL(xt_unregister_target);
93 xt_register_targets(struct xt_target *target, unsigned int n)
98 for (i = 0; i < n; i++) {
99 err = xt_register_target(&target[i]);
107 xt_unregister_targets(target, i);
110 EXPORT_SYMBOL(xt_register_targets);
113 xt_unregister_targets(struct xt_target *target, unsigned int n)
117 for (i = 0; i < n; i++)
118 xt_unregister_target(&target[i]);
120 EXPORT_SYMBOL(xt_unregister_targets);
123 xt_register_match(struct xt_match *match)
125 u_int8_t af = match->family;
128 ret = mutex_lock_interruptible(&xt[af].mutex);
132 list_add(&match->list, &xt[af].match);
133 mutex_unlock(&xt[af].mutex);
137 EXPORT_SYMBOL(xt_register_match);
140 xt_unregister_match(struct xt_match *match)
142 u_int8_t af = match->family;
144 mutex_lock(&xt[af].mutex);
145 list_del(&match->list);
146 mutex_unlock(&xt[af].mutex);
148 EXPORT_SYMBOL(xt_unregister_match);
151 xt_register_matches(struct xt_match *match, unsigned int n)
156 for (i = 0; i < n; i++) {
157 err = xt_register_match(&match[i]);
165 xt_unregister_matches(match, i);
168 EXPORT_SYMBOL(xt_register_matches);
171 xt_unregister_matches(struct xt_match *match, unsigned int n)
175 for (i = 0; i < n; i++)
176 xt_unregister_match(&match[i]);
178 EXPORT_SYMBOL(xt_unregister_matches);
182 * These are weird, but module loading must not be done with mutex
183 * held (since they will register), and we have to have a single
184 * function to use try_then_request_module().
187 /* Find match, grabs ref. Returns ERR_PTR() on error. */
188 struct xt_match *xt_find_match(u8 af, const char *name, u8 revision)
193 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
194 return ERR_PTR(-EINTR);
196 list_for_each_entry(m, &xt[af].match, list) {
197 if (strcmp(m->name, name) == 0) {
198 if (m->revision == revision) {
199 if (try_module_get(m->me)) {
200 mutex_unlock(&xt[af].mutex);
204 err = -EPROTOTYPE; /* Found something. */
207 mutex_unlock(&xt[af].mutex);
209 if (af != NFPROTO_UNSPEC)
210 /* Try searching again in the family-independent list */
211 return xt_find_match(NFPROTO_UNSPEC, name, revision);
215 EXPORT_SYMBOL(xt_find_match);
218 xt_request_find_match(uint8_t nfproto, const char *name, uint8_t revision)
220 struct xt_match *match;
222 match = try_then_request_module(xt_find_match(nfproto, name, revision),
223 "%st_%s", xt_prefix[nfproto], name);
224 return (match != NULL) ? match : ERR_PTR(-ENOENT);
226 EXPORT_SYMBOL_GPL(xt_request_find_match);
228 /* Find target, grabs ref. Returns ERR_PTR() on error. */
229 struct xt_target *xt_find_target(u8 af, const char *name, u8 revision)
234 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
235 return ERR_PTR(-EINTR);
237 list_for_each_entry(t, &xt[af].target, list) {
238 if (strcmp(t->name, name) == 0) {
239 if (t->revision == revision) {
240 if (try_module_get(t->me)) {
241 mutex_unlock(&xt[af].mutex);
245 err = -EPROTOTYPE; /* Found something. */
248 mutex_unlock(&xt[af].mutex);
250 if (af != NFPROTO_UNSPEC)
251 /* Try searching again in the family-independent list */
252 return xt_find_target(NFPROTO_UNSPEC, name, revision);
256 EXPORT_SYMBOL(xt_find_target);
258 struct xt_target *xt_request_find_target(u8 af, const char *name, u8 revision)
260 struct xt_target *target;
262 target = try_then_request_module(xt_find_target(af, name, revision),
263 "%st_%s", xt_prefix[af], name);
264 return (target != NULL) ? target : ERR_PTR(-ENOENT);
266 EXPORT_SYMBOL_GPL(xt_request_find_target);
268 static int match_revfn(u8 af, const char *name, u8 revision, int *bestp)
270 const struct xt_match *m;
273 list_for_each_entry(m, &xt[af].match, list) {
274 if (strcmp(m->name, name) == 0) {
275 if (m->revision > *bestp)
276 *bestp = m->revision;
277 if (m->revision == revision)
282 if (af != NFPROTO_UNSPEC && !have_rev)
283 return match_revfn(NFPROTO_UNSPEC, name, revision, bestp);
288 static int target_revfn(u8 af, const char *name, u8 revision, int *bestp)
290 const struct xt_target *t;
293 list_for_each_entry(t, &xt[af].target, list) {
294 if (strcmp(t->name, name) == 0) {
295 if (t->revision > *bestp)
296 *bestp = t->revision;
297 if (t->revision == revision)
302 if (af != NFPROTO_UNSPEC && !have_rev)
303 return target_revfn(NFPROTO_UNSPEC, name, revision, bestp);
308 /* Returns true or false (if no such extension at all) */
309 int xt_find_revision(u8 af, const char *name, u8 revision, int target,
312 int have_rev, best = -1;
314 if (mutex_lock_interruptible(&xt[af].mutex) != 0) {
319 have_rev = target_revfn(af, name, revision, &best);
321 have_rev = match_revfn(af, name, revision, &best);
322 mutex_unlock(&xt[af].mutex);
324 /* Nothing at all? Return 0 to try loading module. */
332 *err = -EPROTONOSUPPORT;
335 EXPORT_SYMBOL_GPL(xt_find_revision);
337 static char *textify_hooks(char *buf, size_t size, unsigned int mask)
339 static const char *const names[] = {
340 "PREROUTING", "INPUT", "FORWARD",
341 "OUTPUT", "POSTROUTING", "BROUTING",
349 for (i = 0; i < ARRAY_SIZE(names); ++i) {
350 if (!(mask & (1 << i)))
352 res = snprintf(p, size, "%s%s", np ? "/" : "", names[i]);
363 int xt_check_match(struct xt_mtchk_param *par,
364 unsigned int size, u_int8_t proto, bool inv_proto)
368 if (XT_ALIGN(par->match->matchsize) != size &&
369 par->match->matchsize != -1) {
371 * ebt_among is exempt from centralized matchsize checking
372 * because it uses a dynamic-size data set.
374 pr_err("%s_tables: %s.%u match: invalid size "
375 "%u (kernel) != (user) %u\n",
376 xt_prefix[par->family], par->match->name,
377 par->match->revision,
378 XT_ALIGN(par->match->matchsize), size);
381 if (par->match->table != NULL &&
382 strcmp(par->match->table, par->table) != 0) {
383 pr_err("%s_tables: %s match: only valid in %s table, not %s\n",
384 xt_prefix[par->family], par->match->name,
385 par->match->table, par->table);
388 if (par->match->hooks && (par->hook_mask & ~par->match->hooks) != 0) {
389 char used[64], allow[64];
391 pr_err("%s_tables: %s match: used from hooks %s, but only "
393 xt_prefix[par->family], par->match->name,
394 textify_hooks(used, sizeof(used), par->hook_mask),
395 textify_hooks(allow, sizeof(allow), par->match->hooks));
398 if (par->match->proto && (par->match->proto != proto || inv_proto)) {
399 pr_err("%s_tables: %s match: only valid for protocol %u\n",
400 xt_prefix[par->family], par->match->name,
404 if (par->match->checkentry != NULL) {
405 ret = par->match->checkentry(par);
409 /* Flag up potential errors. */
414 EXPORT_SYMBOL_GPL(xt_check_match);
417 int xt_compat_add_offset(u_int8_t af, unsigned int offset, short delta)
419 struct compat_delta *tmp;
421 tmp = kmalloc(sizeof(struct compat_delta), GFP_KERNEL);
425 tmp->offset = offset;
428 if (xt[af].compat_offsets) {
429 tmp->next = xt[af].compat_offsets->next;
430 xt[af].compat_offsets->next = tmp;
432 xt[af].compat_offsets = tmp;
437 EXPORT_SYMBOL_GPL(xt_compat_add_offset);
439 void xt_compat_flush_offsets(u_int8_t af)
441 struct compat_delta *tmp, *next;
443 if (xt[af].compat_offsets) {
444 for (tmp = xt[af].compat_offsets; tmp; tmp = next) {
448 xt[af].compat_offsets = NULL;
451 EXPORT_SYMBOL_GPL(xt_compat_flush_offsets);
453 int xt_compat_calc_jump(u_int8_t af, unsigned int offset)
455 struct compat_delta *tmp;
458 for (tmp = xt[af].compat_offsets, delta = 0; tmp; tmp = tmp->next)
459 if (tmp->offset < offset)
463 EXPORT_SYMBOL_GPL(xt_compat_calc_jump);
465 int xt_compat_match_offset(const struct xt_match *match)
467 u_int16_t csize = match->compatsize ? : match->matchsize;
468 return XT_ALIGN(match->matchsize) - COMPAT_XT_ALIGN(csize);
470 EXPORT_SYMBOL_GPL(xt_compat_match_offset);
472 int xt_compat_match_from_user(struct xt_entry_match *m, void **dstptr,
475 const struct xt_match *match = m->u.kernel.match;
476 struct compat_xt_entry_match *cm = (struct compat_xt_entry_match *)m;
477 int pad, off = xt_compat_match_offset(match);
478 u_int16_t msize = cm->u.user.match_size;
481 memcpy(m, cm, sizeof(*cm));
482 if (match->compat_from_user)
483 match->compat_from_user(m->data, cm->data);
485 memcpy(m->data, cm->data, msize - sizeof(*cm));
486 pad = XT_ALIGN(match->matchsize) - match->matchsize;
488 memset(m->data + match->matchsize, 0, pad);
491 m->u.user.match_size = msize;
497 EXPORT_SYMBOL_GPL(xt_compat_match_from_user);
499 int xt_compat_match_to_user(const struct xt_entry_match *m,
500 void __user **dstptr, unsigned int *size)
502 const struct xt_match *match = m->u.kernel.match;
503 struct compat_xt_entry_match __user *cm = *dstptr;
504 int off = xt_compat_match_offset(match);
505 u_int16_t msize = m->u.user.match_size - off;
507 if (copy_to_user(cm, m, sizeof(*cm)) ||
508 put_user(msize, &cm->u.user.match_size) ||
509 copy_to_user(cm->u.user.name, m->u.kernel.match->name,
510 strlen(m->u.kernel.match->name) + 1))
513 if (match->compat_to_user) {
514 if (match->compat_to_user((void __user *)cm->data, m->data))
517 if (copy_to_user(cm->data, m->data, msize - sizeof(*cm)))
525 EXPORT_SYMBOL_GPL(xt_compat_match_to_user);
526 #endif /* CONFIG_COMPAT */
528 int xt_check_target(struct xt_tgchk_param *par,
529 unsigned int size, u_int8_t proto, bool inv_proto)
533 if (XT_ALIGN(par->target->targetsize) != size) {
534 pr_err("%s_tables: %s.%u target: invalid size "
535 "%u (kernel) != (user) %u\n",
536 xt_prefix[par->family], par->target->name,
537 par->target->revision,
538 XT_ALIGN(par->target->targetsize), size);
541 if (par->target->table != NULL &&
542 strcmp(par->target->table, par->table) != 0) {
543 pr_err("%s_tables: %s target: only valid in %s table, not %s\n",
544 xt_prefix[par->family], par->target->name,
545 par->target->table, par->table);
548 if (par->target->hooks && (par->hook_mask & ~par->target->hooks) != 0) {
549 char used[64], allow[64];
551 pr_err("%s_tables: %s target: used from hooks %s, but only "
553 xt_prefix[par->family], par->target->name,
554 textify_hooks(used, sizeof(used), par->hook_mask),
555 textify_hooks(allow, sizeof(allow), par->target->hooks));
558 if (par->target->proto && (par->target->proto != proto || inv_proto)) {
559 pr_err("%s_tables: %s target: only valid for protocol %u\n",
560 xt_prefix[par->family], par->target->name,
564 if (par->target->checkentry != NULL) {
565 ret = par->target->checkentry(par);
569 /* Flag up potential errors. */
574 EXPORT_SYMBOL_GPL(xt_check_target);
577 int xt_compat_target_offset(const struct xt_target *target)
579 u_int16_t csize = target->compatsize ? : target->targetsize;
580 return XT_ALIGN(target->targetsize) - COMPAT_XT_ALIGN(csize);
582 EXPORT_SYMBOL_GPL(xt_compat_target_offset);
584 void xt_compat_target_from_user(struct xt_entry_target *t, void **dstptr,
587 const struct xt_target *target = t->u.kernel.target;
588 struct compat_xt_entry_target *ct = (struct compat_xt_entry_target *)t;
589 int pad, off = xt_compat_target_offset(target);
590 u_int16_t tsize = ct->u.user.target_size;
593 memcpy(t, ct, sizeof(*ct));
594 if (target->compat_from_user)
595 target->compat_from_user(t->data, ct->data);
597 memcpy(t->data, ct->data, tsize - sizeof(*ct));
598 pad = XT_ALIGN(target->targetsize) - target->targetsize;
600 memset(t->data + target->targetsize, 0, pad);
603 t->u.user.target_size = tsize;
608 EXPORT_SYMBOL_GPL(xt_compat_target_from_user);
610 int xt_compat_target_to_user(const struct xt_entry_target *t,
611 void __user **dstptr, unsigned int *size)
613 const struct xt_target *target = t->u.kernel.target;
614 struct compat_xt_entry_target __user *ct = *dstptr;
615 int off = xt_compat_target_offset(target);
616 u_int16_t tsize = t->u.user.target_size - off;
618 if (copy_to_user(ct, t, sizeof(*ct)) ||
619 put_user(tsize, &ct->u.user.target_size) ||
620 copy_to_user(ct->u.user.name, t->u.kernel.target->name,
621 strlen(t->u.kernel.target->name) + 1))
624 if (target->compat_to_user) {
625 if (target->compat_to_user((void __user *)ct->data, t->data))
628 if (copy_to_user(ct->data, t->data, tsize - sizeof(*ct)))
636 EXPORT_SYMBOL_GPL(xt_compat_target_to_user);
639 struct xt_table_info *xt_alloc_table_info(unsigned int size)
641 struct xt_table_info *newinfo;
644 /* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */
645 if ((SMP_ALIGN(size) >> PAGE_SHIFT) + 2 > totalram_pages)
648 newinfo = kzalloc(XT_TABLE_INFO_SZ, GFP_KERNEL);
652 newinfo->size = size;
654 for_each_possible_cpu(cpu) {
655 if (size <= PAGE_SIZE)
656 newinfo->entries[cpu] = kmalloc_node(size,
660 newinfo->entries[cpu] = vmalloc_node(size,
663 if (newinfo->entries[cpu] == NULL) {
664 xt_free_table_info(newinfo);
671 EXPORT_SYMBOL(xt_alloc_table_info);
673 void xt_free_table_info(struct xt_table_info *info)
677 for_each_possible_cpu(cpu) {
678 if (info->size <= PAGE_SIZE)
679 kfree(info->entries[cpu]);
681 vfree(info->entries[cpu]);
685 EXPORT_SYMBOL(xt_free_table_info);
687 /* Find table by name, grabs mutex & ref. Returns ERR_PTR() on error. */
688 struct xt_table *xt_find_table_lock(struct net *net, u_int8_t af,
693 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
694 return ERR_PTR(-EINTR);
696 list_for_each_entry(t, &net->xt.tables[af], list)
697 if (strcmp(t->name, name) == 0 && try_module_get(t->me))
699 mutex_unlock(&xt[af].mutex);
702 EXPORT_SYMBOL_GPL(xt_find_table_lock);
704 void xt_table_unlock(struct xt_table *table)
706 mutex_unlock(&xt[table->af].mutex);
708 EXPORT_SYMBOL_GPL(xt_table_unlock);
711 void xt_compat_lock(u_int8_t af)
713 mutex_lock(&xt[af].compat_mutex);
715 EXPORT_SYMBOL_GPL(xt_compat_lock);
717 void xt_compat_unlock(u_int8_t af)
719 mutex_unlock(&xt[af].compat_mutex);
721 EXPORT_SYMBOL_GPL(xt_compat_unlock);
724 DEFINE_PER_CPU(struct xt_info_lock, xt_info_locks);
725 EXPORT_PER_CPU_SYMBOL_GPL(xt_info_locks);
728 struct xt_table_info *
729 xt_replace_table(struct xt_table *table,
730 unsigned int num_counters,
731 struct xt_table_info *newinfo,
734 struct xt_table_info *private;
736 /* Do the substitution. */
738 private = table->private;
740 /* Check inside lock: is the old number correct? */
741 if (num_counters != private->number) {
742 pr_debug("num_counters != table->private->number (%u/%u)\n",
743 num_counters, private->number);
749 table->private = newinfo;
750 newinfo->initial_entries = private->initial_entries;
753 * Even though table entries have now been swapped, other CPU's
754 * may still be using the old entries. This is okay, because
755 * resynchronization happens because of the locking done
756 * during the get_counters() routine.
762 EXPORT_SYMBOL_GPL(xt_replace_table);
764 struct xt_table *xt_register_table(struct net *net,
765 const struct xt_table *input_table,
766 struct xt_table_info *bootstrap,
767 struct xt_table_info *newinfo)
770 struct xt_table_info *private;
771 struct xt_table *t, *table;
773 /* Don't add one object to multiple lists. */
774 table = kmemdup(input_table, sizeof(struct xt_table), GFP_KERNEL);
780 ret = mutex_lock_interruptible(&xt[table->af].mutex);
784 /* Don't autoload: we'd eat our tail... */
785 list_for_each_entry(t, &net->xt.tables[table->af], list) {
786 if (strcmp(t->name, table->name) == 0) {
792 /* Simplifies replace_table code. */
793 table->private = bootstrap;
795 if (!xt_replace_table(table, 0, newinfo, &ret))
798 private = table->private;
799 pr_debug("table->private->number = %u\n", private->number);
801 /* save number of initial entries */
802 private->initial_entries = private->number;
804 list_add(&table->list, &net->xt.tables[table->af]);
805 mutex_unlock(&xt[table->af].mutex);
809 mutex_unlock(&xt[table->af].mutex);
815 EXPORT_SYMBOL_GPL(xt_register_table);
817 void *xt_unregister_table(struct xt_table *table)
819 struct xt_table_info *private;
821 mutex_lock(&xt[table->af].mutex);
822 private = table->private;
823 list_del(&table->list);
824 mutex_unlock(&xt[table->af].mutex);
829 EXPORT_SYMBOL_GPL(xt_unregister_table);
831 #ifdef CONFIG_PROC_FS
832 struct xt_names_priv {
833 struct seq_net_private p;
836 static void *xt_table_seq_start(struct seq_file *seq, loff_t *pos)
838 struct xt_names_priv *priv = seq->private;
839 struct net *net = seq_file_net(seq);
840 u_int8_t af = priv->af;
842 mutex_lock(&xt[af].mutex);
843 return seq_list_start(&net->xt.tables[af], *pos);
846 static void *xt_table_seq_next(struct seq_file *seq, void *v, loff_t *pos)
848 struct xt_names_priv *priv = seq->private;
849 struct net *net = seq_file_net(seq);
850 u_int8_t af = priv->af;
852 return seq_list_next(v, &net->xt.tables[af], pos);
855 static void xt_table_seq_stop(struct seq_file *seq, void *v)
857 struct xt_names_priv *priv = seq->private;
858 u_int8_t af = priv->af;
860 mutex_unlock(&xt[af].mutex);
863 static int xt_table_seq_show(struct seq_file *seq, void *v)
865 struct xt_table *table = list_entry(v, struct xt_table, list);
867 if (strlen(table->name))
868 return seq_printf(seq, "%s\n", table->name);
873 static const struct seq_operations xt_table_seq_ops = {
874 .start = xt_table_seq_start,
875 .next = xt_table_seq_next,
876 .stop = xt_table_seq_stop,
877 .show = xt_table_seq_show,
880 static int xt_table_open(struct inode *inode, struct file *file)
883 struct xt_names_priv *priv;
885 ret = seq_open_net(inode, file, &xt_table_seq_ops,
886 sizeof(struct xt_names_priv));
888 priv = ((struct seq_file *)file->private_data)->private;
889 priv->af = (unsigned long)PDE(inode)->data;
894 static const struct file_operations xt_table_ops = {
895 .owner = THIS_MODULE,
896 .open = xt_table_open,
899 .release = seq_release_net,
903 * Traverse state for ip{,6}_{tables,matches} for helping crossing
904 * the multi-AF mutexes.
906 struct nf_mttg_trav {
907 struct list_head *head, *curr;
908 uint8_t class, nfproto;
913 MTTG_TRAV_NFP_UNSPEC,
918 static void *xt_mttg_seq_next(struct seq_file *seq, void *v, loff_t *ppos,
921 static const uint8_t next_class[] = {
922 [MTTG_TRAV_NFP_UNSPEC] = MTTG_TRAV_NFP_SPEC,
923 [MTTG_TRAV_NFP_SPEC] = MTTG_TRAV_DONE,
925 struct nf_mttg_trav *trav = seq->private;
927 switch (trav->class) {
929 trav->class = MTTG_TRAV_NFP_UNSPEC;
930 mutex_lock(&xt[NFPROTO_UNSPEC].mutex);
931 trav->head = trav->curr = is_target ?
932 &xt[NFPROTO_UNSPEC].target : &xt[NFPROTO_UNSPEC].match;
934 case MTTG_TRAV_NFP_UNSPEC:
935 trav->curr = trav->curr->next;
936 if (trav->curr != trav->head)
938 mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
939 mutex_lock(&xt[trav->nfproto].mutex);
940 trav->head = trav->curr = is_target ?
941 &xt[trav->nfproto].target : &xt[trav->nfproto].match;
942 trav->class = next_class[trav->class];
944 case MTTG_TRAV_NFP_SPEC:
945 trav->curr = trav->curr->next;
946 if (trav->curr != trav->head)
948 /* fallthru, _stop will unlock */
958 static void *xt_mttg_seq_start(struct seq_file *seq, loff_t *pos,
961 struct nf_mttg_trav *trav = seq->private;
964 trav->class = MTTG_TRAV_INIT;
965 for (j = 0; j < *pos; ++j)
966 if (xt_mttg_seq_next(seq, NULL, NULL, is_target) == NULL)
971 static void xt_mttg_seq_stop(struct seq_file *seq, void *v)
973 struct nf_mttg_trav *trav = seq->private;
975 switch (trav->class) {
976 case MTTG_TRAV_NFP_UNSPEC:
977 mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
979 case MTTG_TRAV_NFP_SPEC:
980 mutex_unlock(&xt[trav->nfproto].mutex);
985 static void *xt_match_seq_start(struct seq_file *seq, loff_t *pos)
987 return xt_mttg_seq_start(seq, pos, false);
990 static void *xt_match_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
992 return xt_mttg_seq_next(seq, v, ppos, false);
995 static int xt_match_seq_show(struct seq_file *seq, void *v)
997 const struct nf_mttg_trav *trav = seq->private;
998 const struct xt_match *match;
1000 switch (trav->class) {
1001 case MTTG_TRAV_NFP_UNSPEC:
1002 case MTTG_TRAV_NFP_SPEC:
1003 if (trav->curr == trav->head)
1005 match = list_entry(trav->curr, struct xt_match, list);
1006 return (*match->name == '\0') ? 0 :
1007 seq_printf(seq, "%s\n", match->name);
1012 static const struct seq_operations xt_match_seq_ops = {
1013 .start = xt_match_seq_start,
1014 .next = xt_match_seq_next,
1015 .stop = xt_mttg_seq_stop,
1016 .show = xt_match_seq_show,
1019 static int xt_match_open(struct inode *inode, struct file *file)
1021 struct seq_file *seq;
1022 struct nf_mttg_trav *trav;
1025 trav = kmalloc(sizeof(*trav), GFP_KERNEL);
1029 ret = seq_open(file, &xt_match_seq_ops);
1035 seq = file->private_data;
1036 seq->private = trav;
1037 trav->nfproto = (unsigned long)PDE(inode)->data;
1041 static const struct file_operations xt_match_ops = {
1042 .owner = THIS_MODULE,
1043 .open = xt_match_open,
1045 .llseek = seq_lseek,
1046 .release = seq_release_private,
1049 static void *xt_target_seq_start(struct seq_file *seq, loff_t *pos)
1051 return xt_mttg_seq_start(seq, pos, true);
1054 static void *xt_target_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
1056 return xt_mttg_seq_next(seq, v, ppos, true);
1059 static int xt_target_seq_show(struct seq_file *seq, void *v)
1061 const struct nf_mttg_trav *trav = seq->private;
1062 const struct xt_target *target;
1064 switch (trav->class) {
1065 case MTTG_TRAV_NFP_UNSPEC:
1066 case MTTG_TRAV_NFP_SPEC:
1067 if (trav->curr == trav->head)
1069 target = list_entry(trav->curr, struct xt_target, list);
1070 return (*target->name == '\0') ? 0 :
1071 seq_printf(seq, "%s\n", target->name);
1076 static const struct seq_operations xt_target_seq_ops = {
1077 .start = xt_target_seq_start,
1078 .next = xt_target_seq_next,
1079 .stop = xt_mttg_seq_stop,
1080 .show = xt_target_seq_show,
1083 static int xt_target_open(struct inode *inode, struct file *file)
1085 struct seq_file *seq;
1086 struct nf_mttg_trav *trav;
1089 trav = kmalloc(sizeof(*trav), GFP_KERNEL);
1093 ret = seq_open(file, &xt_target_seq_ops);
1099 seq = file->private_data;
1100 seq->private = trav;
1101 trav->nfproto = (unsigned long)PDE(inode)->data;
1105 static const struct file_operations xt_target_ops = {
1106 .owner = THIS_MODULE,
1107 .open = xt_target_open,
1109 .llseek = seq_lseek,
1110 .release = seq_release_private,
1113 #define FORMAT_TABLES "_tables_names"
1114 #define FORMAT_MATCHES "_tables_matches"
1115 #define FORMAT_TARGETS "_tables_targets"
1117 #endif /* CONFIG_PROC_FS */
1120 * xt_hook_link - set up hooks for a new table
1121 * @table: table with metadata needed to set up hooks
1122 * @fn: Hook function
1124 * This function will take care of creating and registering the necessary
1125 * Netfilter hooks for XT tables.
1127 struct nf_hook_ops *xt_hook_link(const struct xt_table *table, nf_hookfn *fn)
1129 unsigned int hook_mask = table->valid_hooks;
1130 uint8_t i, num_hooks = hweight32(hook_mask);
1132 struct nf_hook_ops *ops;
1135 ops = kmalloc(sizeof(*ops) * num_hooks, GFP_KERNEL);
1137 return ERR_PTR(-ENOMEM);
1139 for (i = 0, hooknum = 0; i < num_hooks && hook_mask != 0;
1140 hook_mask >>= 1, ++hooknum) {
1141 if (!(hook_mask & 1))
1144 ops[i].owner = table->me;
1145 ops[i].pf = table->af;
1146 ops[i].hooknum = hooknum;
1147 ops[i].priority = table->priority;
1151 ret = nf_register_hooks(ops, num_hooks);
1154 return ERR_PTR(ret);
1159 EXPORT_SYMBOL_GPL(xt_hook_link);
1162 * xt_hook_unlink - remove hooks for a table
1163 * @ops: nf_hook_ops array as returned by nf_hook_link
1164 * @hook_mask: the very same mask that was passed to nf_hook_link
1166 void xt_hook_unlink(const struct xt_table *table, struct nf_hook_ops *ops)
1168 nf_unregister_hooks(ops, hweight32(table->valid_hooks));
1171 EXPORT_SYMBOL_GPL(xt_hook_unlink);
1173 int xt_proto_init(struct net *net, u_int8_t af)
1175 #ifdef CONFIG_PROC_FS
1176 char buf[XT_FUNCTION_MAXNAMELEN];
1177 struct proc_dir_entry *proc;
1180 if (af >= ARRAY_SIZE(xt_prefix))
1184 #ifdef CONFIG_PROC_FS
1185 strlcpy(buf, xt_prefix[af], sizeof(buf));
1186 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1187 proc = proc_create_data(buf, 0440, net->proc_net, &xt_table_ops,
1188 (void *)(unsigned long)af);
1192 strlcpy(buf, xt_prefix[af], sizeof(buf));
1193 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1194 proc = proc_create_data(buf, 0440, net->proc_net, &xt_match_ops,
1195 (void *)(unsigned long)af);
1197 goto out_remove_tables;
1199 strlcpy(buf, xt_prefix[af], sizeof(buf));
1200 strlcat(buf, FORMAT_TARGETS, sizeof(buf));
1201 proc = proc_create_data(buf, 0440, net->proc_net, &xt_target_ops,
1202 (void *)(unsigned long)af);
1204 goto out_remove_matches;
1209 #ifdef CONFIG_PROC_FS
1211 strlcpy(buf, xt_prefix[af], sizeof(buf));
1212 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1213 proc_net_remove(net, buf);
1216 strlcpy(buf, xt_prefix[af], sizeof(buf));
1217 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1218 proc_net_remove(net, buf);
1223 EXPORT_SYMBOL_GPL(xt_proto_init);
1225 void xt_proto_fini(struct net *net, u_int8_t af)
1227 #ifdef CONFIG_PROC_FS
1228 char buf[XT_FUNCTION_MAXNAMELEN];
1230 strlcpy(buf, xt_prefix[af], sizeof(buf));
1231 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1232 proc_net_remove(net, buf);
1234 strlcpy(buf, xt_prefix[af], sizeof(buf));
1235 strlcat(buf, FORMAT_TARGETS, sizeof(buf));
1236 proc_net_remove(net, buf);
1238 strlcpy(buf, xt_prefix[af], sizeof(buf));
1239 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1240 proc_net_remove(net, buf);
1241 #endif /*CONFIG_PROC_FS*/
1243 EXPORT_SYMBOL_GPL(xt_proto_fini);
1245 static int __net_init xt_net_init(struct net *net)
1249 for (i = 0; i < NFPROTO_NUMPROTO; i++)
1250 INIT_LIST_HEAD(&net->xt.tables[i]);
1254 static struct pernet_operations xt_net_ops = {
1255 .init = xt_net_init,
1258 static int __init xt_init(void)
1263 for_each_possible_cpu(i) {
1264 struct xt_info_lock *lock = &per_cpu(xt_info_locks, i);
1265 spin_lock_init(&lock->lock);
1269 xt = kmalloc(sizeof(struct xt_af) * NFPROTO_NUMPROTO, GFP_KERNEL);
1273 for (i = 0; i < NFPROTO_NUMPROTO; i++) {
1274 mutex_init(&xt[i].mutex);
1275 #ifdef CONFIG_COMPAT
1276 mutex_init(&xt[i].compat_mutex);
1277 xt[i].compat_offsets = NULL;
1279 INIT_LIST_HEAD(&xt[i].target);
1280 INIT_LIST_HEAD(&xt[i].match);
1282 rv = register_pernet_subsys(&xt_net_ops);
1288 static void __exit xt_fini(void)
1290 unregister_pernet_subsys(&xt_net_ops);
1294 module_init(xt_init);
1295 module_exit(xt_fini);