2 * x_tables core - Backend for {ip,ip6,arp}_tables
4 * Copyright (C) 2006-2006 Harald Welte <laforge@netfilter.org>
5 * Copyright (C) 2006-2012 Patrick McHardy <kaber@trash.net>
7 * Based on existing ip_tables code which is
8 * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
9 * Copyright (C) 2000-2005 Netfilter Core Team <coreteam@netfilter.org>
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
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>
27 #include <linux/slab.h>
28 #include <linux/audit.h>
29 #include <net/net_namespace.h>
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>
37 MODULE_LICENSE("GPL");
38 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
39 MODULE_DESCRIPTION("{ip,ip6,arp,eb}_tables backend module");
41 #define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1))
44 unsigned int offset; /* offset in kernel */
45 int delta; /* delta in 32bit user land */
50 struct list_head match;
51 struct list_head target;
53 struct mutex compat_mutex;
54 struct compat_delta *compat_tab;
55 unsigned int number; /* number of slots in compat_tab[] */
56 unsigned int cur; /* number of used slots in compat_tab[] */
60 static struct xt_af *xt;
62 static 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",
70 /* Allow this many total (re)entries. */
71 static const unsigned int xt_jumpstack_multiplier = 2;
73 /* Registration hooks for targets. */
75 xt_register_target(struct xt_target *target)
77 u_int8_t af = target->family;
80 ret = mutex_lock_interruptible(&xt[af].mutex);
83 list_add(&target->list, &xt[af].target);
84 mutex_unlock(&xt[af].mutex);
87 EXPORT_SYMBOL(xt_register_target);
90 xt_unregister_target(struct xt_target *target)
92 u_int8_t af = target->family;
94 mutex_lock(&xt[af].mutex);
95 list_del(&target->list);
96 mutex_unlock(&xt[af].mutex);
98 EXPORT_SYMBOL(xt_unregister_target);
101 xt_register_targets(struct xt_target *target, unsigned int n)
106 for (i = 0; i < n; i++) {
107 err = xt_register_target(&target[i]);
115 xt_unregister_targets(target, i);
118 EXPORT_SYMBOL(xt_register_targets);
121 xt_unregister_targets(struct xt_target *target, unsigned int n)
124 xt_unregister_target(&target[n]);
126 EXPORT_SYMBOL(xt_unregister_targets);
129 xt_register_match(struct xt_match *match)
131 u_int8_t af = match->family;
134 ret = mutex_lock_interruptible(&xt[af].mutex);
138 list_add(&match->list, &xt[af].match);
139 mutex_unlock(&xt[af].mutex);
143 EXPORT_SYMBOL(xt_register_match);
146 xt_unregister_match(struct xt_match *match)
148 u_int8_t af = match->family;
150 mutex_lock(&xt[af].mutex);
151 list_del(&match->list);
152 mutex_unlock(&xt[af].mutex);
154 EXPORT_SYMBOL(xt_unregister_match);
157 xt_register_matches(struct xt_match *match, unsigned int n)
162 for (i = 0; i < n; i++) {
163 err = xt_register_match(&match[i]);
171 xt_unregister_matches(match, i);
174 EXPORT_SYMBOL(xt_register_matches);
177 xt_unregister_matches(struct xt_match *match, unsigned int n)
180 xt_unregister_match(&match[n]);
182 EXPORT_SYMBOL(xt_unregister_matches);
186 * These are weird, but module loading must not be done with mutex
187 * held (since they will register), and we have to have a single
191 /* Find match, grabs ref. Returns ERR_PTR() on error. */
192 struct xt_match *xt_find_match(u8 af, const char *name, u8 revision)
197 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
198 return ERR_PTR(-EINTR);
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);
208 err = -EPROTOTYPE; /* Found something. */
211 mutex_unlock(&xt[af].mutex);
213 if (af != NFPROTO_UNSPEC)
214 /* Try searching again in the family-independent list */
215 return xt_find_match(NFPROTO_UNSPEC, name, revision);
219 EXPORT_SYMBOL(xt_find_match);
222 xt_request_find_match(uint8_t nfproto, const char *name, uint8_t revision)
224 struct xt_match *match;
226 match = xt_find_match(nfproto, name, revision);
228 request_module("%st_%s", xt_prefix[nfproto], name);
229 match = xt_find_match(nfproto, name, revision);
234 EXPORT_SYMBOL_GPL(xt_request_find_match);
236 /* Find target, grabs ref. Returns ERR_PTR() on error. */
237 struct xt_target *xt_find_target(u8 af, const char *name, u8 revision)
242 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
243 return ERR_PTR(-EINTR);
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);
253 err = -EPROTOTYPE; /* Found something. */
256 mutex_unlock(&xt[af].mutex);
258 if (af != NFPROTO_UNSPEC)
259 /* Try searching again in the family-independent list */
260 return xt_find_target(NFPROTO_UNSPEC, name, revision);
264 EXPORT_SYMBOL(xt_find_target);
266 struct xt_target *xt_request_find_target(u8 af, const char *name, u8 revision)
268 struct xt_target *target;
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);
278 EXPORT_SYMBOL_GPL(xt_request_find_target);
280 static int match_revfn(u8 af, const char *name, u8 revision, int *bestp)
282 const struct xt_match *m;
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)
294 if (af != NFPROTO_UNSPEC && !have_rev)
295 return match_revfn(NFPROTO_UNSPEC, name, revision, bestp);
300 static int target_revfn(u8 af, const char *name, u8 revision, int *bestp)
302 const struct xt_target *t;
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)
314 if (af != NFPROTO_UNSPEC && !have_rev)
315 return target_revfn(NFPROTO_UNSPEC, name, revision, bestp);
320 /* Returns true or false (if no such extension at all) */
321 int xt_find_revision(u8 af, const char *name, u8 revision, int target,
324 int have_rev, best = -1;
326 if (mutex_lock_interruptible(&xt[af].mutex) != 0) {
331 have_rev = target_revfn(af, name, revision, &best);
333 have_rev = match_revfn(af, name, revision, &best);
334 mutex_unlock(&xt[af].mutex);
336 /* Nothing at all? Return 0 to try loading module. */
344 *err = -EPROTONOSUPPORT;
347 EXPORT_SYMBOL_GPL(xt_find_revision);
350 textify_hooks(char *buf, size_t size, unsigned int mask, uint8_t nfproto)
352 static const char *const inetbr_names[] = {
353 "PREROUTING", "INPUT", "FORWARD",
354 "OUTPUT", "POSTROUTING", "BROUTING",
356 static const char *const arp_names[] = {
357 "INPUT", "FORWARD", "OUTPUT",
359 const char *const *names;
365 names = (nfproto == NFPROTO_ARP) ? arp_names : inetbr_names;
366 max = (nfproto == NFPROTO_ARP) ? ARRAY_SIZE(arp_names) :
367 ARRAY_SIZE(inetbr_names);
369 for (i = 0; i < max; ++i) {
370 if (!(mask & (1 << i)))
372 res = snprintf(p, size, "%s%s", np ? "/" : "", names[i]);
383 int xt_check_match(struct xt_mtchk_param *par,
384 unsigned int size, u_int8_t proto, bool inv_proto)
388 if (XT_ALIGN(par->match->matchsize) != size &&
389 par->match->matchsize != -1) {
391 * ebt_among is exempt from centralized matchsize checking
392 * because it uses a dynamic-size data set.
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);
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);
408 if (par->match->hooks && (par->hook_mask & ~par->match->hooks) != 0) {
409 char used[64], allow[64];
411 pr_err("%s_tables: %s match: used from hooks %s, but only "
413 xt_prefix[par->family], par->match->name,
414 textify_hooks(used, sizeof(used), par->hook_mask,
416 textify_hooks(allow, sizeof(allow), par->match->hooks,
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,
426 if (par->match->checkentry != NULL) {
427 ret = par->match->checkentry(par);
431 /* Flag up potential errors. */
436 EXPORT_SYMBOL_GPL(xt_check_match);
439 int xt_compat_add_offset(u_int8_t af, unsigned int offset, int delta)
441 struct xt_af *xp = &xt[af];
443 if (!xp->compat_tab) {
446 xp->compat_tab = vmalloc(sizeof(struct compat_delta) * xp->number);
452 if (xp->cur >= xp->number)
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;
462 EXPORT_SYMBOL_GPL(xt_compat_add_offset);
464 void xt_compat_flush_offsets(u_int8_t af)
466 if (xt[af].compat_tab) {
467 vfree(xt[af].compat_tab);
468 xt[af].compat_tab = NULL;
473 EXPORT_SYMBOL_GPL(xt_compat_flush_offsets);
475 int xt_compat_calc_jump(u_int8_t af, unsigned int offset)
477 struct compat_delta *tmp = xt[af].compat_tab;
478 int mid, left = 0, right = xt[af].cur - 1;
480 while (left <= right) {
481 mid = (left + right) >> 1;
482 if (offset > tmp[mid].offset)
484 else if (offset < tmp[mid].offset)
487 return mid ? tmp[mid - 1].delta : 0;
489 return left ? tmp[left - 1].delta : 0;
491 EXPORT_SYMBOL_GPL(xt_compat_calc_jump);
493 void xt_compat_init_offsets(u_int8_t af, unsigned int number)
495 xt[af].number = number;
498 EXPORT_SYMBOL(xt_compat_init_offsets);
500 int xt_compat_match_offset(const struct xt_match *match)
502 u_int16_t csize = match->compatsize ? : match->matchsize;
503 return XT_ALIGN(match->matchsize) - COMPAT_XT_ALIGN(csize);
505 EXPORT_SYMBOL_GPL(xt_compat_match_offset);
507 int xt_compat_match_from_user(struct xt_entry_match *m, void **dstptr,
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;
516 memcpy(m, cm, sizeof(*cm));
517 if (match->compat_from_user)
518 match->compat_from_user(m->data, cm->data);
520 memcpy(m->data, cm->data, msize - sizeof(*cm));
521 pad = XT_ALIGN(match->matchsize) - match->matchsize;
523 memset(m->data + match->matchsize, 0, pad);
526 m->u.user.match_size = msize;
532 EXPORT_SYMBOL_GPL(xt_compat_match_from_user);
534 int xt_compat_match_to_user(const struct xt_entry_match *m,
535 void __user **dstptr, unsigned int *size)
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;
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))
548 if (match->compat_to_user) {
549 if (match->compat_to_user((void __user *)cm->data, m->data))
552 if (copy_to_user(cm->data, m->data, msize - sizeof(*cm)))
560 EXPORT_SYMBOL_GPL(xt_compat_match_to_user);
561 #endif /* CONFIG_COMPAT */
563 int xt_check_target(struct xt_tgchk_param *par,
564 unsigned int size, u_int8_t proto, bool inv_proto)
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);
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);
583 if (par->target->hooks && (par->hook_mask & ~par->target->hooks) != 0) {
584 char used[64], allow[64];
586 pr_err("%s_tables: %s target: used from hooks %s, but only "
588 xt_prefix[par->family], par->target->name,
589 textify_hooks(used, sizeof(used), par->hook_mask,
591 textify_hooks(allow, sizeof(allow), par->target->hooks,
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,
601 if (par->target->checkentry != NULL) {
602 ret = par->target->checkentry(par);
606 /* Flag up potential errors. */
611 EXPORT_SYMBOL_GPL(xt_check_target);
614 int xt_compat_target_offset(const struct xt_target *target)
616 u_int16_t csize = target->compatsize ? : target->targetsize;
617 return XT_ALIGN(target->targetsize) - COMPAT_XT_ALIGN(csize);
619 EXPORT_SYMBOL_GPL(xt_compat_target_offset);
621 void xt_compat_target_from_user(struct xt_entry_target *t, void **dstptr,
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;
630 memcpy(t, ct, sizeof(*ct));
631 if (target->compat_from_user)
632 target->compat_from_user(t->data, ct->data);
634 memcpy(t->data, ct->data, tsize - sizeof(*ct));
635 pad = XT_ALIGN(target->targetsize) - target->targetsize;
637 memset(t->data + target->targetsize, 0, pad);
640 t->u.user.target_size = tsize;
645 EXPORT_SYMBOL_GPL(xt_compat_target_from_user);
647 int xt_compat_target_to_user(const struct xt_entry_target *t,
648 void __user **dstptr, unsigned int *size)
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;
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))
661 if (target->compat_to_user) {
662 if (target->compat_to_user((void __user *)ct->data, t->data))
665 if (copy_to_user(ct->data, t->data, tsize - sizeof(*ct)))
673 EXPORT_SYMBOL_GPL(xt_compat_target_to_user);
676 struct xt_table_info *xt_alloc_table_info(unsigned int size)
678 struct xt_table_info *newinfo;
681 /* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */
682 if ((SMP_ALIGN(size) >> PAGE_SHIFT) + 2 > totalram_pages)
685 newinfo = kzalloc(XT_TABLE_INFO_SZ, GFP_KERNEL);
689 newinfo->size = size;
691 for_each_possible_cpu(cpu) {
692 if (size <= PAGE_SIZE)
693 newinfo->entries[cpu] = kmalloc_node(size,
697 newinfo->entries[cpu] = vmalloc_node(size,
700 if (newinfo->entries[cpu] == NULL) {
701 xt_free_table_info(newinfo);
708 EXPORT_SYMBOL(xt_alloc_table_info);
710 void xt_free_table_info(struct xt_table_info *info)
714 for_each_possible_cpu(cpu)
715 kvfree(info->entries[cpu]);
717 if (info->jumpstack != NULL) {
718 for_each_possible_cpu(cpu)
719 kvfree(info->jumpstack[cpu]);
720 kvfree(info->jumpstack);
723 free_percpu(info->stackptr);
727 EXPORT_SYMBOL(xt_free_table_info);
729 /* Find table by name, grabs mutex & ref. Returns ERR_PTR() on error. */
730 struct xt_table *xt_find_table_lock(struct net *net, u_int8_t af,
735 if (mutex_lock_interruptible(&xt[af].mutex) != 0)
736 return ERR_PTR(-EINTR);
738 list_for_each_entry(t, &net->xt.tables[af], list)
739 if (strcmp(t->name, name) == 0 && try_module_get(t->me))
741 mutex_unlock(&xt[af].mutex);
744 EXPORT_SYMBOL_GPL(xt_find_table_lock);
746 void xt_table_unlock(struct xt_table *table)
748 mutex_unlock(&xt[table->af].mutex);
750 EXPORT_SYMBOL_GPL(xt_table_unlock);
753 void xt_compat_lock(u_int8_t af)
755 mutex_lock(&xt[af].compat_mutex);
757 EXPORT_SYMBOL_GPL(xt_compat_lock);
759 void xt_compat_unlock(u_int8_t af)
761 mutex_unlock(&xt[af].compat_mutex);
763 EXPORT_SYMBOL_GPL(xt_compat_unlock);
766 DEFINE_PER_CPU(seqcount_t, xt_recseq);
767 EXPORT_PER_CPU_SYMBOL_GPL(xt_recseq);
769 static int xt_jumpstack_alloc(struct xt_table_info *i)
774 i->stackptr = alloc_percpu(unsigned int);
775 if (i->stackptr == NULL)
778 size = sizeof(void **) * nr_cpu_ids;
779 if (size > PAGE_SIZE)
780 i->jumpstack = vzalloc(size);
782 i->jumpstack = kzalloc(size, GFP_KERNEL);
783 if (i->jumpstack == NULL)
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 newinfo->initial_entries = private->initial_entries;
837 * Ensure contents of newinfo are visible before assigning to
841 table->private = newinfo;
844 * Even though table entries have now been swapped, other CPU's
845 * may still be using the old entries. This is okay, because
846 * resynchronization happens because of the locking done
847 * during the get_counters() routine.
853 struct audit_buffer *ab;
855 ab = audit_log_start(current->audit_context, GFP_KERNEL,
856 AUDIT_NETFILTER_CFG);
858 audit_log_format(ab, "table=%s family=%u entries=%u",
859 table->name, table->af,
868 EXPORT_SYMBOL_GPL(xt_replace_table);
870 struct xt_table *xt_register_table(struct net *net,
871 const struct xt_table *input_table,
872 struct xt_table_info *bootstrap,
873 struct xt_table_info *newinfo)
876 struct xt_table_info *private;
877 struct xt_table *t, *table;
879 /* Don't add one object to multiple lists. */
880 table = kmemdup(input_table, sizeof(struct xt_table), GFP_KERNEL);
886 ret = mutex_lock_interruptible(&xt[table->af].mutex);
890 /* Don't autoload: we'd eat our tail... */
891 list_for_each_entry(t, &net->xt.tables[table->af], list) {
892 if (strcmp(t->name, table->name) == 0) {
898 /* Simplifies replace_table code. */
899 table->private = bootstrap;
901 if (!xt_replace_table(table, 0, newinfo, &ret))
904 private = table->private;
905 pr_debug("table->private->number = %u\n", private->number);
907 /* save number of initial entries */
908 private->initial_entries = private->number;
910 list_add(&table->list, &net->xt.tables[table->af]);
911 mutex_unlock(&xt[table->af].mutex);
915 mutex_unlock(&xt[table->af].mutex);
921 EXPORT_SYMBOL_GPL(xt_register_table);
923 void *xt_unregister_table(struct xt_table *table)
925 struct xt_table_info *private;
927 mutex_lock(&xt[table->af].mutex);
928 private = table->private;
929 list_del(&table->list);
930 mutex_unlock(&xt[table->af].mutex);
935 EXPORT_SYMBOL_GPL(xt_unregister_table);
937 #ifdef CONFIG_PROC_FS
938 struct xt_names_priv {
939 struct seq_net_private p;
942 static void *xt_table_seq_start(struct seq_file *seq, loff_t *pos)
944 struct xt_names_priv *priv = seq->private;
945 struct net *net = seq_file_net(seq);
946 u_int8_t af = priv->af;
948 mutex_lock(&xt[af].mutex);
949 return seq_list_start(&net->xt.tables[af], *pos);
952 static void *xt_table_seq_next(struct seq_file *seq, void *v, loff_t *pos)
954 struct xt_names_priv *priv = seq->private;
955 struct net *net = seq_file_net(seq);
956 u_int8_t af = priv->af;
958 return seq_list_next(v, &net->xt.tables[af], pos);
961 static void xt_table_seq_stop(struct seq_file *seq, void *v)
963 struct xt_names_priv *priv = seq->private;
964 u_int8_t af = priv->af;
966 mutex_unlock(&xt[af].mutex);
969 static int xt_table_seq_show(struct seq_file *seq, void *v)
971 struct xt_table *table = list_entry(v, struct xt_table, list);
973 if (strlen(table->name))
974 return seq_printf(seq, "%s\n", table->name);
979 static const struct seq_operations xt_table_seq_ops = {
980 .start = xt_table_seq_start,
981 .next = xt_table_seq_next,
982 .stop = xt_table_seq_stop,
983 .show = xt_table_seq_show,
986 static int xt_table_open(struct inode *inode, struct file *file)
989 struct xt_names_priv *priv;
991 ret = seq_open_net(inode, file, &xt_table_seq_ops,
992 sizeof(struct xt_names_priv));
994 priv = ((struct seq_file *)file->private_data)->private;
995 priv->af = (unsigned long)PDE_DATA(inode);
1000 static const struct file_operations xt_table_ops = {
1001 .owner = THIS_MODULE,
1002 .open = xt_table_open,
1004 .llseek = seq_lseek,
1005 .release = seq_release_net,
1009 * Traverse state for ip{,6}_{tables,matches} for helping crossing
1010 * the multi-AF mutexes.
1012 struct nf_mttg_trav {
1013 struct list_head *head, *curr;
1014 uint8_t class, nfproto;
1019 MTTG_TRAV_NFP_UNSPEC,
1024 static void *xt_mttg_seq_next(struct seq_file *seq, void *v, loff_t *ppos,
1027 static const uint8_t next_class[] = {
1028 [MTTG_TRAV_NFP_UNSPEC] = MTTG_TRAV_NFP_SPEC,
1029 [MTTG_TRAV_NFP_SPEC] = MTTG_TRAV_DONE,
1031 struct nf_mttg_trav *trav = seq->private;
1033 switch (trav->class) {
1034 case MTTG_TRAV_INIT:
1035 trav->class = MTTG_TRAV_NFP_UNSPEC;
1036 mutex_lock(&xt[NFPROTO_UNSPEC].mutex);
1037 trav->head = trav->curr = is_target ?
1038 &xt[NFPROTO_UNSPEC].target : &xt[NFPROTO_UNSPEC].match;
1040 case MTTG_TRAV_NFP_UNSPEC:
1041 trav->curr = trav->curr->next;
1042 if (trav->curr != trav->head)
1044 mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
1045 mutex_lock(&xt[trav->nfproto].mutex);
1046 trav->head = trav->curr = is_target ?
1047 &xt[trav->nfproto].target : &xt[trav->nfproto].match;
1048 trav->class = next_class[trav->class];
1050 case MTTG_TRAV_NFP_SPEC:
1051 trav->curr = trav->curr->next;
1052 if (trav->curr != trav->head)
1054 /* fallthru, _stop will unlock */
1064 static void *xt_mttg_seq_start(struct seq_file *seq, loff_t *pos,
1067 struct nf_mttg_trav *trav = seq->private;
1070 trav->class = MTTG_TRAV_INIT;
1071 for (j = 0; j < *pos; ++j)
1072 if (xt_mttg_seq_next(seq, NULL, NULL, is_target) == NULL)
1077 static void xt_mttg_seq_stop(struct seq_file *seq, void *v)
1079 struct nf_mttg_trav *trav = seq->private;
1081 switch (trav->class) {
1082 case MTTG_TRAV_NFP_UNSPEC:
1083 mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
1085 case MTTG_TRAV_NFP_SPEC:
1086 mutex_unlock(&xt[trav->nfproto].mutex);
1091 static void *xt_match_seq_start(struct seq_file *seq, loff_t *pos)
1093 return xt_mttg_seq_start(seq, pos, false);
1096 static void *xt_match_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
1098 return xt_mttg_seq_next(seq, v, ppos, false);
1101 static int xt_match_seq_show(struct seq_file *seq, void *v)
1103 const struct nf_mttg_trav *trav = seq->private;
1104 const struct xt_match *match;
1106 switch (trav->class) {
1107 case MTTG_TRAV_NFP_UNSPEC:
1108 case MTTG_TRAV_NFP_SPEC:
1109 if (trav->curr == trav->head)
1111 match = list_entry(trav->curr, struct xt_match, list);
1112 return (*match->name == '\0') ? 0 :
1113 seq_printf(seq, "%s\n", match->name);
1118 static const struct seq_operations xt_match_seq_ops = {
1119 .start = xt_match_seq_start,
1120 .next = xt_match_seq_next,
1121 .stop = xt_mttg_seq_stop,
1122 .show = xt_match_seq_show,
1125 static int xt_match_open(struct inode *inode, struct file *file)
1127 struct seq_file *seq;
1128 struct nf_mttg_trav *trav;
1131 trav = kmalloc(sizeof(*trav), GFP_KERNEL);
1135 ret = seq_open(file, &xt_match_seq_ops);
1141 seq = file->private_data;
1142 seq->private = trav;
1143 trav->nfproto = (unsigned long)PDE_DATA(inode);
1147 static const struct file_operations xt_match_ops = {
1148 .owner = THIS_MODULE,
1149 .open = xt_match_open,
1151 .llseek = seq_lseek,
1152 .release = seq_release_private,
1155 static void *xt_target_seq_start(struct seq_file *seq, loff_t *pos)
1157 return xt_mttg_seq_start(seq, pos, true);
1160 static void *xt_target_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
1162 return xt_mttg_seq_next(seq, v, ppos, true);
1165 static int xt_target_seq_show(struct seq_file *seq, void *v)
1167 const struct nf_mttg_trav *trav = seq->private;
1168 const struct xt_target *target;
1170 switch (trav->class) {
1171 case MTTG_TRAV_NFP_UNSPEC:
1172 case MTTG_TRAV_NFP_SPEC:
1173 if (trav->curr == trav->head)
1175 target = list_entry(trav->curr, struct xt_target, list);
1176 return (*target->name == '\0') ? 0 :
1177 seq_printf(seq, "%s\n", target->name);
1182 static const struct seq_operations xt_target_seq_ops = {
1183 .start = xt_target_seq_start,
1184 .next = xt_target_seq_next,
1185 .stop = xt_mttg_seq_stop,
1186 .show = xt_target_seq_show,
1189 static int xt_target_open(struct inode *inode, struct file *file)
1191 struct seq_file *seq;
1192 struct nf_mttg_trav *trav;
1195 trav = kmalloc(sizeof(*trav), GFP_KERNEL);
1199 ret = seq_open(file, &xt_target_seq_ops);
1205 seq = file->private_data;
1206 seq->private = trav;
1207 trav->nfproto = (unsigned long)PDE_DATA(inode);
1211 static const struct file_operations xt_target_ops = {
1212 .owner = THIS_MODULE,
1213 .open = xt_target_open,
1215 .llseek = seq_lseek,
1216 .release = seq_release_private,
1219 #define FORMAT_TABLES "_tables_names"
1220 #define FORMAT_MATCHES "_tables_matches"
1221 #define FORMAT_TARGETS "_tables_targets"
1223 #endif /* CONFIG_PROC_FS */
1226 * xt_hook_link - set up hooks for a new table
1227 * @table: table with metadata needed to set up hooks
1228 * @fn: Hook function
1230 * This function will take care of creating and registering the necessary
1231 * Netfilter hooks for XT tables.
1233 struct nf_hook_ops *xt_hook_link(const struct xt_table *table, nf_hookfn *fn)
1235 unsigned int hook_mask = table->valid_hooks;
1236 uint8_t i, num_hooks = hweight32(hook_mask);
1238 struct nf_hook_ops *ops;
1241 ops = kmalloc(sizeof(*ops) * num_hooks, GFP_KERNEL);
1243 return ERR_PTR(-ENOMEM);
1245 for (i = 0, hooknum = 0; i < num_hooks && hook_mask != 0;
1246 hook_mask >>= 1, ++hooknum) {
1247 if (!(hook_mask & 1))
1250 ops[i].owner = table->me;
1251 ops[i].pf = table->af;
1252 ops[i].hooknum = hooknum;
1253 ops[i].priority = table->priority;
1257 ret = nf_register_hooks(ops, num_hooks);
1260 return ERR_PTR(ret);
1265 EXPORT_SYMBOL_GPL(xt_hook_link);
1268 * xt_hook_unlink - remove hooks for a table
1269 * @ops: nf_hook_ops array as returned by nf_hook_link
1270 * @hook_mask: the very same mask that was passed to nf_hook_link
1272 void xt_hook_unlink(const struct xt_table *table, struct nf_hook_ops *ops)
1274 nf_unregister_hooks(ops, hweight32(table->valid_hooks));
1277 EXPORT_SYMBOL_GPL(xt_hook_unlink);
1279 int xt_proto_init(struct net *net, u_int8_t af)
1281 #ifdef CONFIG_PROC_FS
1282 char buf[XT_FUNCTION_MAXNAMELEN];
1283 struct proc_dir_entry *proc;
1286 if (af >= ARRAY_SIZE(xt_prefix))
1290 #ifdef CONFIG_PROC_FS
1291 strlcpy(buf, xt_prefix[af], sizeof(buf));
1292 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1293 proc = proc_create_data(buf, 0440, net->proc_net, &xt_table_ops,
1294 (void *)(unsigned long)af);
1298 strlcpy(buf, xt_prefix[af], sizeof(buf));
1299 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1300 proc = proc_create_data(buf, 0440, net->proc_net, &xt_match_ops,
1301 (void *)(unsigned long)af);
1303 goto out_remove_tables;
1305 strlcpy(buf, xt_prefix[af], sizeof(buf));
1306 strlcat(buf, FORMAT_TARGETS, sizeof(buf));
1307 proc = proc_create_data(buf, 0440, net->proc_net, &xt_target_ops,
1308 (void *)(unsigned long)af);
1310 goto out_remove_matches;
1315 #ifdef CONFIG_PROC_FS
1317 strlcpy(buf, xt_prefix[af], sizeof(buf));
1318 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1319 remove_proc_entry(buf, net->proc_net);
1322 strlcpy(buf, xt_prefix[af], sizeof(buf));
1323 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1324 remove_proc_entry(buf, net->proc_net);
1329 EXPORT_SYMBOL_GPL(xt_proto_init);
1331 void xt_proto_fini(struct net *net, u_int8_t af)
1333 #ifdef CONFIG_PROC_FS
1334 char buf[XT_FUNCTION_MAXNAMELEN];
1336 strlcpy(buf, xt_prefix[af], sizeof(buf));
1337 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1338 remove_proc_entry(buf, net->proc_net);
1340 strlcpy(buf, xt_prefix[af], sizeof(buf));
1341 strlcat(buf, FORMAT_TARGETS, sizeof(buf));
1342 remove_proc_entry(buf, net->proc_net);
1344 strlcpy(buf, xt_prefix[af], sizeof(buf));
1345 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1346 remove_proc_entry(buf, net->proc_net);
1347 #endif /*CONFIG_PROC_FS*/
1349 EXPORT_SYMBOL_GPL(xt_proto_fini);
1351 static int __net_init xt_net_init(struct net *net)
1355 for (i = 0; i < NFPROTO_NUMPROTO; i++)
1356 INIT_LIST_HEAD(&net->xt.tables[i]);
1360 static struct pernet_operations xt_net_ops = {
1361 .init = xt_net_init,
1364 static int __init xt_init(void)
1369 for_each_possible_cpu(i) {
1370 seqcount_init(&per_cpu(xt_recseq, i));
1373 xt = kmalloc(sizeof(struct xt_af) * NFPROTO_NUMPROTO, GFP_KERNEL);
1377 for (i = 0; i < NFPROTO_NUMPROTO; i++) {
1378 mutex_init(&xt[i].mutex);
1379 #ifdef CONFIG_COMPAT
1380 mutex_init(&xt[i].compat_mutex);
1381 xt[i].compat_tab = NULL;
1383 INIT_LIST_HEAD(&xt[i].target);
1384 INIT_LIST_HEAD(&xt[i].match);
1386 rv = register_pernet_subsys(&xt_net_ops);
1392 static void __exit xt_fini(void)
1394 unregister_pernet_subsys(&xt_net_ops);
1398 module_init(xt_init);
1399 module_exit(xt_fini);