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 <linux/user_namespace.h>
30 #include <net/net_namespace.h>
32 #include <linux/netfilter/x_tables.h>
33 #include <linux/netfilter_arp.h>
34 #include <linux/netfilter_ipv4/ip_tables.h>
35 #include <linux/netfilter_ipv6/ip6_tables.h>
36 #include <linux/netfilter_arp/arp_tables.h>
38 MODULE_LICENSE("GPL");
39 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
40 MODULE_DESCRIPTION("{ip,ip6,arp,eb}_tables backend module");
42 #define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1))
45 unsigned int offset
; /* offset in kernel */
46 int delta
; /* delta in 32bit user land */
51 struct list_head match
;
52 struct list_head target
;
54 struct mutex compat_mutex
;
55 struct compat_delta
*compat_tab
;
56 unsigned int number
; /* number of slots in compat_tab[] */
57 unsigned int cur
; /* number of used slots in compat_tab[] */
61 static struct xt_af
*xt
;
63 static const char *const xt_prefix
[NFPROTO_NUMPROTO
] = {
64 [NFPROTO_UNSPEC
] = "x",
65 [NFPROTO_IPV4
] = "ip",
66 [NFPROTO_ARP
] = "arp",
67 [NFPROTO_BRIDGE
] = "eb",
68 [NFPROTO_IPV6
] = "ip6",
71 /* Registration hooks for targets. */
72 int xt_register_target(struct xt_target
*target
)
74 u_int8_t af
= target
->family
;
76 mutex_lock(&xt
[af
].mutex
);
77 list_add(&target
->list
, &xt
[af
].target
);
78 mutex_unlock(&xt
[af
].mutex
);
81 EXPORT_SYMBOL(xt_register_target
);
84 xt_unregister_target(struct xt_target
*target
)
86 u_int8_t af
= target
->family
;
88 mutex_lock(&xt
[af
].mutex
);
89 list_del(&target
->list
);
90 mutex_unlock(&xt
[af
].mutex
);
92 EXPORT_SYMBOL(xt_unregister_target
);
95 xt_register_targets(struct xt_target
*target
, unsigned int n
)
100 for (i
= 0; i
< n
; i
++) {
101 err
= xt_register_target(&target
[i
]);
109 xt_unregister_targets(target
, i
);
112 EXPORT_SYMBOL(xt_register_targets
);
115 xt_unregister_targets(struct xt_target
*target
, unsigned int n
)
118 xt_unregister_target(&target
[n
]);
120 EXPORT_SYMBOL(xt_unregister_targets
);
122 int xt_register_match(struct xt_match
*match
)
124 u_int8_t af
= match
->family
;
126 mutex_lock(&xt
[af
].mutex
);
127 list_add(&match
->list
, &xt
[af
].match
);
128 mutex_unlock(&xt
[af
].mutex
);
131 EXPORT_SYMBOL(xt_register_match
);
134 xt_unregister_match(struct xt_match
*match
)
136 u_int8_t af
= match
->family
;
138 mutex_lock(&xt
[af
].mutex
);
139 list_del(&match
->list
);
140 mutex_unlock(&xt
[af
].mutex
);
142 EXPORT_SYMBOL(xt_unregister_match
);
145 xt_register_matches(struct xt_match
*match
, unsigned int n
)
150 for (i
= 0; i
< n
; i
++) {
151 err
= xt_register_match(&match
[i
]);
159 xt_unregister_matches(match
, i
);
162 EXPORT_SYMBOL(xt_register_matches
);
165 xt_unregister_matches(struct xt_match
*match
, unsigned int n
)
168 xt_unregister_match(&match
[n
]);
170 EXPORT_SYMBOL(xt_unregister_matches
);
174 * These are weird, but module loading must not be done with mutex
175 * held (since they will register), and we have to have a single
179 /* Find match, grabs ref. Returns ERR_PTR() on error. */
180 struct xt_match
*xt_find_match(u8 af
, const char *name
, u8 revision
)
185 mutex_lock(&xt
[af
].mutex
);
186 list_for_each_entry(m
, &xt
[af
].match
, list
) {
187 if (strcmp(m
->name
, name
) == 0) {
188 if (m
->revision
== revision
) {
189 if (try_module_get(m
->me
)) {
190 mutex_unlock(&xt
[af
].mutex
);
194 err
= -EPROTOTYPE
; /* Found something. */
197 mutex_unlock(&xt
[af
].mutex
);
199 if (af
!= NFPROTO_UNSPEC
)
200 /* Try searching again in the family-independent list */
201 return xt_find_match(NFPROTO_UNSPEC
, name
, revision
);
205 EXPORT_SYMBOL(xt_find_match
);
208 xt_request_find_match(uint8_t nfproto
, const char *name
, uint8_t revision
)
210 struct xt_match
*match
;
212 match
= xt_find_match(nfproto
, name
, revision
);
214 request_module("%st_%s", xt_prefix
[nfproto
], name
);
215 match
= xt_find_match(nfproto
, name
, revision
);
220 EXPORT_SYMBOL_GPL(xt_request_find_match
);
222 /* Find target, grabs ref. Returns ERR_PTR() on error. */
223 struct xt_target
*xt_find_target(u8 af
, const char *name
, u8 revision
)
228 mutex_lock(&xt
[af
].mutex
);
229 list_for_each_entry(t
, &xt
[af
].target
, list
) {
230 if (strcmp(t
->name
, name
) == 0) {
231 if (t
->revision
== revision
) {
232 if (try_module_get(t
->me
)) {
233 mutex_unlock(&xt
[af
].mutex
);
237 err
= -EPROTOTYPE
; /* Found something. */
240 mutex_unlock(&xt
[af
].mutex
);
242 if (af
!= NFPROTO_UNSPEC
)
243 /* Try searching again in the family-independent list */
244 return xt_find_target(NFPROTO_UNSPEC
, name
, revision
);
248 EXPORT_SYMBOL(xt_find_target
);
250 struct xt_target
*xt_request_find_target(u8 af
, const char *name
, u8 revision
)
252 struct xt_target
*target
;
254 target
= xt_find_target(af
, name
, revision
);
255 if (IS_ERR(target
)) {
256 request_module("%st_%s", xt_prefix
[af
], name
);
257 target
= xt_find_target(af
, name
, revision
);
262 EXPORT_SYMBOL_GPL(xt_request_find_target
);
264 static int match_revfn(u8 af
, const char *name
, u8 revision
, int *bestp
)
266 const struct xt_match
*m
;
269 list_for_each_entry(m
, &xt
[af
].match
, list
) {
270 if (strcmp(m
->name
, name
) == 0) {
271 if (m
->revision
> *bestp
)
272 *bestp
= m
->revision
;
273 if (m
->revision
== revision
)
278 if (af
!= NFPROTO_UNSPEC
&& !have_rev
)
279 return match_revfn(NFPROTO_UNSPEC
, name
, revision
, bestp
);
284 static int target_revfn(u8 af
, const char *name
, u8 revision
, int *bestp
)
286 const struct xt_target
*t
;
289 list_for_each_entry(t
, &xt
[af
].target
, list
) {
290 if (strcmp(t
->name
, name
) == 0) {
291 if (t
->revision
> *bestp
)
292 *bestp
= t
->revision
;
293 if (t
->revision
== revision
)
298 if (af
!= NFPROTO_UNSPEC
&& !have_rev
)
299 return target_revfn(NFPROTO_UNSPEC
, name
, revision
, bestp
);
304 /* Returns true or false (if no such extension at all) */
305 int xt_find_revision(u8 af
, const char *name
, u8 revision
, int target
,
308 int have_rev
, best
= -1;
310 mutex_lock(&xt
[af
].mutex
);
312 have_rev
= target_revfn(af
, name
, revision
, &best
);
314 have_rev
= match_revfn(af
, name
, revision
, &best
);
315 mutex_unlock(&xt
[af
].mutex
);
317 /* Nothing at all? Return 0 to try loading module. */
325 *err
= -EPROTONOSUPPORT
;
328 EXPORT_SYMBOL_GPL(xt_find_revision
);
331 textify_hooks(char *buf
, size_t size
, unsigned int mask
, uint8_t nfproto
)
333 static const char *const inetbr_names
[] = {
334 "PREROUTING", "INPUT", "FORWARD",
335 "OUTPUT", "POSTROUTING", "BROUTING",
337 static const char *const arp_names
[] = {
338 "INPUT", "FORWARD", "OUTPUT",
340 const char *const *names
;
346 names
= (nfproto
== NFPROTO_ARP
) ? arp_names
: inetbr_names
;
347 max
= (nfproto
== NFPROTO_ARP
) ? ARRAY_SIZE(arp_names
) :
348 ARRAY_SIZE(inetbr_names
);
350 for (i
= 0; i
< max
; ++i
) {
351 if (!(mask
& (1 << i
)))
353 res
= snprintf(p
, size
, "%s%s", np
? "/" : "", names
[i
]);
364 int xt_check_match(struct xt_mtchk_param
*par
,
365 unsigned int size
, u_int8_t proto
, bool inv_proto
)
369 if (XT_ALIGN(par
->match
->matchsize
) != size
&&
370 par
->match
->matchsize
!= -1) {
372 * ebt_among is exempt from centralized matchsize checking
373 * because it uses a dynamic-size data set.
375 pr_err("%s_tables: %s.%u match: invalid size "
376 "%u (kernel) != (user) %u\n",
377 xt_prefix
[par
->family
], par
->match
->name
,
378 par
->match
->revision
,
379 XT_ALIGN(par
->match
->matchsize
), size
);
382 if (par
->match
->table
!= NULL
&&
383 strcmp(par
->match
->table
, par
->table
) != 0) {
384 pr_err("%s_tables: %s match: only valid in %s table, not %s\n",
385 xt_prefix
[par
->family
], par
->match
->name
,
386 par
->match
->table
, par
->table
);
389 if (par
->match
->hooks
&& (par
->hook_mask
& ~par
->match
->hooks
) != 0) {
390 char used
[64], allow
[64];
392 pr_err("%s_tables: %s match: used from hooks %s, but only "
394 xt_prefix
[par
->family
], par
->match
->name
,
395 textify_hooks(used
, sizeof(used
), par
->hook_mask
,
397 textify_hooks(allow
, sizeof(allow
), par
->match
->hooks
,
401 if (par
->match
->proto
&& (par
->match
->proto
!= proto
|| inv_proto
)) {
402 pr_err("%s_tables: %s match: only valid for protocol %u\n",
403 xt_prefix
[par
->family
], par
->match
->name
,
407 if (par
->match
->checkentry
!= NULL
) {
408 ret
= par
->match
->checkentry(par
);
412 /* Flag up potential errors. */
417 EXPORT_SYMBOL_GPL(xt_check_match
);
420 int xt_compat_add_offset(u_int8_t af
, unsigned int offset
, int delta
)
422 struct xt_af
*xp
= &xt
[af
];
424 if (!xp
->compat_tab
) {
427 xp
->compat_tab
= vmalloc(sizeof(struct compat_delta
) * xp
->number
);
433 if (xp
->cur
>= xp
->number
)
437 delta
+= xp
->compat_tab
[xp
->cur
- 1].delta
;
438 xp
->compat_tab
[xp
->cur
].offset
= offset
;
439 xp
->compat_tab
[xp
->cur
].delta
= delta
;
443 EXPORT_SYMBOL_GPL(xt_compat_add_offset
);
445 void xt_compat_flush_offsets(u_int8_t af
)
447 if (xt
[af
].compat_tab
) {
448 vfree(xt
[af
].compat_tab
);
449 xt
[af
].compat_tab
= NULL
;
454 EXPORT_SYMBOL_GPL(xt_compat_flush_offsets
);
456 int xt_compat_calc_jump(u_int8_t af
, unsigned int offset
)
458 struct compat_delta
*tmp
= xt
[af
].compat_tab
;
459 int mid
, left
= 0, right
= xt
[af
].cur
- 1;
461 while (left
<= right
) {
462 mid
= (left
+ right
) >> 1;
463 if (offset
> tmp
[mid
].offset
)
465 else if (offset
< tmp
[mid
].offset
)
468 return mid
? tmp
[mid
- 1].delta
: 0;
470 return left
? tmp
[left
- 1].delta
: 0;
472 EXPORT_SYMBOL_GPL(xt_compat_calc_jump
);
474 void xt_compat_init_offsets(u_int8_t af
, unsigned int number
)
476 xt
[af
].number
= number
;
479 EXPORT_SYMBOL(xt_compat_init_offsets
);
481 int xt_compat_match_offset(const struct xt_match
*match
)
483 u_int16_t csize
= match
->compatsize
? : match
->matchsize
;
484 return XT_ALIGN(match
->matchsize
) - COMPAT_XT_ALIGN(csize
);
486 EXPORT_SYMBOL_GPL(xt_compat_match_offset
);
488 int xt_compat_match_from_user(struct xt_entry_match
*m
, void **dstptr
,
491 const struct xt_match
*match
= m
->u
.kernel
.match
;
492 struct compat_xt_entry_match
*cm
= (struct compat_xt_entry_match
*)m
;
493 int pad
, off
= xt_compat_match_offset(match
);
494 u_int16_t msize
= cm
->u
.user
.match_size
;
497 memcpy(m
, cm
, sizeof(*cm
));
498 if (match
->compat_from_user
)
499 match
->compat_from_user(m
->data
, cm
->data
);
501 memcpy(m
->data
, cm
->data
, msize
- sizeof(*cm
));
502 pad
= XT_ALIGN(match
->matchsize
) - match
->matchsize
;
504 memset(m
->data
+ match
->matchsize
, 0, pad
);
507 m
->u
.user
.match_size
= msize
;
513 EXPORT_SYMBOL_GPL(xt_compat_match_from_user
);
515 int xt_compat_match_to_user(const struct xt_entry_match
*m
,
516 void __user
**dstptr
, unsigned int *size
)
518 const struct xt_match
*match
= m
->u
.kernel
.match
;
519 struct compat_xt_entry_match __user
*cm
= *dstptr
;
520 int off
= xt_compat_match_offset(match
);
521 u_int16_t msize
= m
->u
.user
.match_size
- off
;
523 if (copy_to_user(cm
, m
, sizeof(*cm
)) ||
524 put_user(msize
, &cm
->u
.user
.match_size
) ||
525 copy_to_user(cm
->u
.user
.name
, m
->u
.kernel
.match
->name
,
526 strlen(m
->u
.kernel
.match
->name
) + 1))
529 if (match
->compat_to_user
) {
530 if (match
->compat_to_user((void __user
*)cm
->data
, m
->data
))
533 if (copy_to_user(cm
->data
, m
->data
, msize
- sizeof(*cm
)))
541 EXPORT_SYMBOL_GPL(xt_compat_match_to_user
);
542 #endif /* CONFIG_COMPAT */
544 int xt_check_target(struct xt_tgchk_param
*par
,
545 unsigned int size
, u_int8_t proto
, bool inv_proto
)
549 if (XT_ALIGN(par
->target
->targetsize
) != size
) {
550 pr_err("%s_tables: %s.%u target: invalid size "
551 "%u (kernel) != (user) %u\n",
552 xt_prefix
[par
->family
], par
->target
->name
,
553 par
->target
->revision
,
554 XT_ALIGN(par
->target
->targetsize
), size
);
557 if (par
->target
->table
!= NULL
&&
558 strcmp(par
->target
->table
, par
->table
) != 0) {
559 pr_err("%s_tables: %s target: only valid in %s table, not %s\n",
560 xt_prefix
[par
->family
], par
->target
->name
,
561 par
->target
->table
, par
->table
);
564 if (par
->target
->hooks
&& (par
->hook_mask
& ~par
->target
->hooks
) != 0) {
565 char used
[64], allow
[64];
567 pr_err("%s_tables: %s target: used from hooks %s, but only "
569 xt_prefix
[par
->family
], par
->target
->name
,
570 textify_hooks(used
, sizeof(used
), par
->hook_mask
,
572 textify_hooks(allow
, sizeof(allow
), par
->target
->hooks
,
576 if (par
->target
->proto
&& (par
->target
->proto
!= proto
|| inv_proto
)) {
577 pr_err("%s_tables: %s target: only valid for protocol %u\n",
578 xt_prefix
[par
->family
], par
->target
->name
,
582 if (par
->target
->checkentry
!= NULL
) {
583 ret
= par
->target
->checkentry(par
);
587 /* Flag up potential errors. */
592 EXPORT_SYMBOL_GPL(xt_check_target
);
595 int xt_compat_target_offset(const struct xt_target
*target
)
597 u_int16_t csize
= target
->compatsize
? : target
->targetsize
;
598 return XT_ALIGN(target
->targetsize
) - COMPAT_XT_ALIGN(csize
);
600 EXPORT_SYMBOL_GPL(xt_compat_target_offset
);
602 void xt_compat_target_from_user(struct xt_entry_target
*t
, void **dstptr
,
605 const struct xt_target
*target
= t
->u
.kernel
.target
;
606 struct compat_xt_entry_target
*ct
= (struct compat_xt_entry_target
*)t
;
607 int pad
, off
= xt_compat_target_offset(target
);
608 u_int16_t tsize
= ct
->u
.user
.target_size
;
611 memcpy(t
, ct
, sizeof(*ct
));
612 if (target
->compat_from_user
)
613 target
->compat_from_user(t
->data
, ct
->data
);
615 memcpy(t
->data
, ct
->data
, tsize
- sizeof(*ct
));
616 pad
= XT_ALIGN(target
->targetsize
) - target
->targetsize
;
618 memset(t
->data
+ target
->targetsize
, 0, pad
);
621 t
->u
.user
.target_size
= tsize
;
626 EXPORT_SYMBOL_GPL(xt_compat_target_from_user
);
628 int xt_compat_target_to_user(const struct xt_entry_target
*t
,
629 void __user
**dstptr
, unsigned int *size
)
631 const struct xt_target
*target
= t
->u
.kernel
.target
;
632 struct compat_xt_entry_target __user
*ct
= *dstptr
;
633 int off
= xt_compat_target_offset(target
);
634 u_int16_t tsize
= t
->u
.user
.target_size
- off
;
636 if (copy_to_user(ct
, t
, sizeof(*ct
)) ||
637 put_user(tsize
, &ct
->u
.user
.target_size
) ||
638 copy_to_user(ct
->u
.user
.name
, t
->u
.kernel
.target
->name
,
639 strlen(t
->u
.kernel
.target
->name
) + 1))
642 if (target
->compat_to_user
) {
643 if (target
->compat_to_user((void __user
*)ct
->data
, t
->data
))
646 if (copy_to_user(ct
->data
, t
->data
, tsize
- sizeof(*ct
)))
654 EXPORT_SYMBOL_GPL(xt_compat_target_to_user
);
657 struct xt_table_info
*xt_alloc_table_info(unsigned int size
)
659 struct xt_table_info
*info
= NULL
;
660 size_t sz
= sizeof(*info
) + size
;
662 /* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */
663 if ((SMP_ALIGN(size
) >> PAGE_SHIFT
) + 2 > totalram_pages
)
666 if (sz
<= (PAGE_SIZE
<< PAGE_ALLOC_COSTLY_ORDER
))
667 info
= kmalloc(sz
, GFP_KERNEL
| __GFP_NOWARN
| __GFP_NORETRY
);
673 memset(info
, 0, sizeof(*info
));
677 EXPORT_SYMBOL(xt_alloc_table_info
);
679 void xt_free_table_info(struct xt_table_info
*info
)
683 if (info
->jumpstack
!= NULL
) {
684 for_each_possible_cpu(cpu
)
685 kvfree(info
->jumpstack
[cpu
]);
686 kvfree(info
->jumpstack
);
691 EXPORT_SYMBOL(xt_free_table_info
);
693 /* Find table by name, grabs mutex & ref. Returns ERR_PTR() on error. */
694 struct xt_table
*xt_find_table_lock(struct net
*net
, u_int8_t af
,
699 mutex_lock(&xt
[af
].mutex
);
700 list_for_each_entry(t
, &net
->xt
.tables
[af
], list
)
701 if (strcmp(t
->name
, name
) == 0 && try_module_get(t
->me
))
703 mutex_unlock(&xt
[af
].mutex
);
706 EXPORT_SYMBOL_GPL(xt_find_table_lock
);
708 void xt_table_unlock(struct xt_table
*table
)
710 mutex_unlock(&xt
[table
->af
].mutex
);
712 EXPORT_SYMBOL_GPL(xt_table_unlock
);
715 void xt_compat_lock(u_int8_t af
)
717 mutex_lock(&xt
[af
].compat_mutex
);
719 EXPORT_SYMBOL_GPL(xt_compat_lock
);
721 void xt_compat_unlock(u_int8_t af
)
723 mutex_unlock(&xt
[af
].compat_mutex
);
725 EXPORT_SYMBOL_GPL(xt_compat_unlock
);
728 DEFINE_PER_CPU(seqcount_t
, xt_recseq
);
729 EXPORT_PER_CPU_SYMBOL_GPL(xt_recseq
);
731 struct static_key xt_tee_enabled __read_mostly
;
732 EXPORT_SYMBOL_GPL(xt_tee_enabled
);
734 static int xt_jumpstack_alloc(struct xt_table_info
*i
)
739 size
= sizeof(void **) * nr_cpu_ids
;
740 if (size
> PAGE_SIZE
)
741 i
->jumpstack
= vzalloc(size
);
743 i
->jumpstack
= kzalloc(size
, GFP_KERNEL
);
744 if (i
->jumpstack
== NULL
)
747 /* ruleset without jumps -- no stack needed */
748 if (i
->stacksize
== 0)
751 /* Jumpstack needs to be able to record two full callchains, one
752 * from the first rule set traversal, plus one table reentrancy
753 * via -j TEE without clobbering the callchain that brought us to
756 * This is done by allocating two jumpstacks per cpu, on reentry
757 * the upper half of the stack is used.
759 * see the jumpstack setup in ipt_do_table() for more details.
761 size
= sizeof(void *) * i
->stacksize
* 2u;
762 for_each_possible_cpu(cpu
) {
763 if (size
> PAGE_SIZE
)
764 i
->jumpstack
[cpu
] = vmalloc_node(size
,
767 i
->jumpstack
[cpu
] = kmalloc_node(size
,
768 GFP_KERNEL
, cpu_to_node(cpu
));
769 if (i
->jumpstack
[cpu
] == NULL
)
771 * Freeing will be done later on by the callers. The
772 * chain is: xt_replace_table -> __do_replace ->
773 * do_replace -> xt_free_table_info.
781 struct xt_table_info
*
782 xt_replace_table(struct xt_table
*table
,
783 unsigned int num_counters
,
784 struct xt_table_info
*newinfo
,
787 struct xt_table_info
*private;
790 ret
= xt_jumpstack_alloc(newinfo
);
796 /* Do the substitution. */
798 private = table
->private;
800 /* Check inside lock: is the old number correct? */
801 if (num_counters
!= private->number
) {
802 pr_debug("num_counters != table->private->number (%u/%u)\n",
803 num_counters
, private->number
);
809 newinfo
->initial_entries
= private->initial_entries
;
811 * Ensure contents of newinfo are visible before assigning to
815 table
->private = newinfo
;
818 * Even though table entries have now been swapped, other CPU's
819 * may still be using the old entries. This is okay, because
820 * resynchronization happens because of the locking done
821 * during the get_counters() routine.
827 struct audit_buffer
*ab
;
829 ab
= audit_log_start(current
->audit_context
, GFP_KERNEL
,
830 AUDIT_NETFILTER_CFG
);
832 audit_log_format(ab
, "table=%s family=%u entries=%u",
833 table
->name
, table
->af
,
842 EXPORT_SYMBOL_GPL(xt_replace_table
);
844 struct xt_table
*xt_register_table(struct net
*net
,
845 const struct xt_table
*input_table
,
846 struct xt_table_info
*bootstrap
,
847 struct xt_table_info
*newinfo
)
850 struct xt_table_info
*private;
851 struct xt_table
*t
, *table
;
853 /* Don't add one object to multiple lists. */
854 table
= kmemdup(input_table
, sizeof(struct xt_table
), GFP_KERNEL
);
860 mutex_lock(&xt
[table
->af
].mutex
);
861 /* Don't autoload: we'd eat our tail... */
862 list_for_each_entry(t
, &net
->xt
.tables
[table
->af
], list
) {
863 if (strcmp(t
->name
, table
->name
) == 0) {
869 /* Simplifies replace_table code. */
870 table
->private = bootstrap
;
872 if (!xt_replace_table(table
, 0, newinfo
, &ret
))
875 private = table
->private;
876 pr_debug("table->private->number = %u\n", private->number
);
878 /* save number of initial entries */
879 private->initial_entries
= private->number
;
881 list_add(&table
->list
, &net
->xt
.tables
[table
->af
]);
882 mutex_unlock(&xt
[table
->af
].mutex
);
886 mutex_unlock(&xt
[table
->af
].mutex
);
891 EXPORT_SYMBOL_GPL(xt_register_table
);
893 void *xt_unregister_table(struct xt_table
*table
)
895 struct xt_table_info
*private;
897 mutex_lock(&xt
[table
->af
].mutex
);
898 private = table
->private;
899 list_del(&table
->list
);
900 mutex_unlock(&xt
[table
->af
].mutex
);
905 EXPORT_SYMBOL_GPL(xt_unregister_table
);
907 #ifdef CONFIG_PROC_FS
908 struct xt_names_priv
{
909 struct seq_net_private p
;
912 static void *xt_table_seq_start(struct seq_file
*seq
, loff_t
*pos
)
914 struct xt_names_priv
*priv
= seq
->private;
915 struct net
*net
= seq_file_net(seq
);
916 u_int8_t af
= priv
->af
;
918 mutex_lock(&xt
[af
].mutex
);
919 return seq_list_start(&net
->xt
.tables
[af
], *pos
);
922 static void *xt_table_seq_next(struct seq_file
*seq
, void *v
, loff_t
*pos
)
924 struct xt_names_priv
*priv
= seq
->private;
925 struct net
*net
= seq_file_net(seq
);
926 u_int8_t af
= priv
->af
;
928 return seq_list_next(v
, &net
->xt
.tables
[af
], pos
);
931 static void xt_table_seq_stop(struct seq_file
*seq
, void *v
)
933 struct xt_names_priv
*priv
= seq
->private;
934 u_int8_t af
= priv
->af
;
936 mutex_unlock(&xt
[af
].mutex
);
939 static int xt_table_seq_show(struct seq_file
*seq
, void *v
)
941 struct xt_table
*table
= list_entry(v
, struct xt_table
, list
);
944 seq_printf(seq
, "%s\n", table
->name
);
948 static const struct seq_operations xt_table_seq_ops
= {
949 .start
= xt_table_seq_start
,
950 .next
= xt_table_seq_next
,
951 .stop
= xt_table_seq_stop
,
952 .show
= xt_table_seq_show
,
955 static int xt_table_open(struct inode
*inode
, struct file
*file
)
958 struct xt_names_priv
*priv
;
960 ret
= seq_open_net(inode
, file
, &xt_table_seq_ops
,
961 sizeof(struct xt_names_priv
));
963 priv
= ((struct seq_file
*)file
->private_data
)->private;
964 priv
->af
= (unsigned long)PDE_DATA(inode
);
969 static const struct file_operations xt_table_ops
= {
970 .owner
= THIS_MODULE
,
971 .open
= xt_table_open
,
974 .release
= seq_release_net
,
978 * Traverse state for ip{,6}_{tables,matches} for helping crossing
979 * the multi-AF mutexes.
981 struct nf_mttg_trav
{
982 struct list_head
*head
, *curr
;
983 uint8_t class, nfproto
;
988 MTTG_TRAV_NFP_UNSPEC
,
993 static void *xt_mttg_seq_next(struct seq_file
*seq
, void *v
, loff_t
*ppos
,
996 static const uint8_t next_class
[] = {
997 [MTTG_TRAV_NFP_UNSPEC
] = MTTG_TRAV_NFP_SPEC
,
998 [MTTG_TRAV_NFP_SPEC
] = MTTG_TRAV_DONE
,
1000 struct nf_mttg_trav
*trav
= seq
->private;
1002 switch (trav
->class) {
1003 case MTTG_TRAV_INIT
:
1004 trav
->class = MTTG_TRAV_NFP_UNSPEC
;
1005 mutex_lock(&xt
[NFPROTO_UNSPEC
].mutex
);
1006 trav
->head
= trav
->curr
= is_target
?
1007 &xt
[NFPROTO_UNSPEC
].target
: &xt
[NFPROTO_UNSPEC
].match
;
1009 case MTTG_TRAV_NFP_UNSPEC
:
1010 trav
->curr
= trav
->curr
->next
;
1011 if (trav
->curr
!= trav
->head
)
1013 mutex_unlock(&xt
[NFPROTO_UNSPEC
].mutex
);
1014 mutex_lock(&xt
[trav
->nfproto
].mutex
);
1015 trav
->head
= trav
->curr
= is_target
?
1016 &xt
[trav
->nfproto
].target
: &xt
[trav
->nfproto
].match
;
1017 trav
->class = next_class
[trav
->class];
1019 case MTTG_TRAV_NFP_SPEC
:
1020 trav
->curr
= trav
->curr
->next
;
1021 if (trav
->curr
!= trav
->head
)
1023 /* fallthru, _stop will unlock */
1033 static void *xt_mttg_seq_start(struct seq_file
*seq
, loff_t
*pos
,
1036 struct nf_mttg_trav
*trav
= seq
->private;
1039 trav
->class = MTTG_TRAV_INIT
;
1040 for (j
= 0; j
< *pos
; ++j
)
1041 if (xt_mttg_seq_next(seq
, NULL
, NULL
, is_target
) == NULL
)
1046 static void xt_mttg_seq_stop(struct seq_file
*seq
, void *v
)
1048 struct nf_mttg_trav
*trav
= seq
->private;
1050 switch (trav
->class) {
1051 case MTTG_TRAV_NFP_UNSPEC
:
1052 mutex_unlock(&xt
[NFPROTO_UNSPEC
].mutex
);
1054 case MTTG_TRAV_NFP_SPEC
:
1055 mutex_unlock(&xt
[trav
->nfproto
].mutex
);
1060 static void *xt_match_seq_start(struct seq_file
*seq
, loff_t
*pos
)
1062 return xt_mttg_seq_start(seq
, pos
, false);
1065 static void *xt_match_seq_next(struct seq_file
*seq
, void *v
, loff_t
*ppos
)
1067 return xt_mttg_seq_next(seq
, v
, ppos
, false);
1070 static int xt_match_seq_show(struct seq_file
*seq
, void *v
)
1072 const struct nf_mttg_trav
*trav
= seq
->private;
1073 const struct xt_match
*match
;
1075 switch (trav
->class) {
1076 case MTTG_TRAV_NFP_UNSPEC
:
1077 case MTTG_TRAV_NFP_SPEC
:
1078 if (trav
->curr
== trav
->head
)
1080 match
= list_entry(trav
->curr
, struct xt_match
, list
);
1082 seq_printf(seq
, "%s\n", match
->name
);
1087 static const struct seq_operations xt_match_seq_ops
= {
1088 .start
= xt_match_seq_start
,
1089 .next
= xt_match_seq_next
,
1090 .stop
= xt_mttg_seq_stop
,
1091 .show
= xt_match_seq_show
,
1094 static int xt_match_open(struct inode
*inode
, struct file
*file
)
1096 struct nf_mttg_trav
*trav
;
1097 trav
= __seq_open_private(file
, &xt_match_seq_ops
, sizeof(*trav
));
1101 trav
->nfproto
= (unsigned long)PDE_DATA(inode
);
1105 static const struct file_operations xt_match_ops
= {
1106 .owner
= THIS_MODULE
,
1107 .open
= xt_match_open
,
1109 .llseek
= seq_lseek
,
1110 .release
= seq_release_private
,
1113 static void *xt_target_seq_start(struct seq_file
*seq
, loff_t
*pos
)
1115 return xt_mttg_seq_start(seq
, pos
, true);
1118 static void *xt_target_seq_next(struct seq_file
*seq
, void *v
, loff_t
*ppos
)
1120 return xt_mttg_seq_next(seq
, v
, ppos
, true);
1123 static int xt_target_seq_show(struct seq_file
*seq
, void *v
)
1125 const struct nf_mttg_trav
*trav
= seq
->private;
1126 const struct xt_target
*target
;
1128 switch (trav
->class) {
1129 case MTTG_TRAV_NFP_UNSPEC
:
1130 case MTTG_TRAV_NFP_SPEC
:
1131 if (trav
->curr
== trav
->head
)
1133 target
= list_entry(trav
->curr
, struct xt_target
, list
);
1135 seq_printf(seq
, "%s\n", target
->name
);
1140 static const struct seq_operations xt_target_seq_ops
= {
1141 .start
= xt_target_seq_start
,
1142 .next
= xt_target_seq_next
,
1143 .stop
= xt_mttg_seq_stop
,
1144 .show
= xt_target_seq_show
,
1147 static int xt_target_open(struct inode
*inode
, struct file
*file
)
1149 struct nf_mttg_trav
*trav
;
1150 trav
= __seq_open_private(file
, &xt_target_seq_ops
, sizeof(*trav
));
1154 trav
->nfproto
= (unsigned long)PDE_DATA(inode
);
1158 static const struct file_operations xt_target_ops
= {
1159 .owner
= THIS_MODULE
,
1160 .open
= xt_target_open
,
1162 .llseek
= seq_lseek
,
1163 .release
= seq_release_private
,
1166 #define FORMAT_TABLES "_tables_names"
1167 #define FORMAT_MATCHES "_tables_matches"
1168 #define FORMAT_TARGETS "_tables_targets"
1170 #endif /* CONFIG_PROC_FS */
1173 * xt_hook_link - set up hooks for a new table
1174 * @table: table with metadata needed to set up hooks
1175 * @fn: Hook function
1177 * This function will take care of creating and registering the necessary
1178 * Netfilter hooks for XT tables.
1180 struct nf_hook_ops
*xt_hook_link(const struct xt_table
*table
, nf_hookfn
*fn
)
1182 unsigned int hook_mask
= table
->valid_hooks
;
1183 uint8_t i
, num_hooks
= hweight32(hook_mask
);
1185 struct nf_hook_ops
*ops
;
1188 ops
= kmalloc(sizeof(*ops
) * num_hooks
, GFP_KERNEL
);
1190 return ERR_PTR(-ENOMEM
);
1192 for (i
= 0, hooknum
= 0; i
< num_hooks
&& hook_mask
!= 0;
1193 hook_mask
>>= 1, ++hooknum
) {
1194 if (!(hook_mask
& 1))
1197 ops
[i
].pf
= table
->af
;
1198 ops
[i
].hooknum
= hooknum
;
1199 ops
[i
].priority
= table
->priority
;
1203 ret
= nf_register_hooks(ops
, num_hooks
);
1206 return ERR_PTR(ret
);
1211 EXPORT_SYMBOL_GPL(xt_hook_link
);
1214 * xt_hook_unlink - remove hooks for a table
1215 * @ops: nf_hook_ops array as returned by nf_hook_link
1216 * @hook_mask: the very same mask that was passed to nf_hook_link
1218 void xt_hook_unlink(const struct xt_table
*table
, struct nf_hook_ops
*ops
)
1220 nf_unregister_hooks(ops
, hweight32(table
->valid_hooks
));
1223 EXPORT_SYMBOL_GPL(xt_hook_unlink
);
1225 int xt_proto_init(struct net
*net
, u_int8_t af
)
1227 #ifdef CONFIG_PROC_FS
1228 char buf
[XT_FUNCTION_MAXNAMELEN
];
1229 struct proc_dir_entry
*proc
;
1234 if (af
>= ARRAY_SIZE(xt_prefix
))
1238 #ifdef CONFIG_PROC_FS
1239 root_uid
= make_kuid(net
->user_ns
, 0);
1240 root_gid
= make_kgid(net
->user_ns
, 0);
1242 strlcpy(buf
, xt_prefix
[af
], sizeof(buf
));
1243 strlcat(buf
, FORMAT_TABLES
, sizeof(buf
));
1244 proc
= proc_create_data(buf
, 0440, net
->proc_net
, &xt_table_ops
,
1245 (void *)(unsigned long)af
);
1248 if (uid_valid(root_uid
) && gid_valid(root_gid
))
1249 proc_set_user(proc
, root_uid
, root_gid
);
1251 strlcpy(buf
, xt_prefix
[af
], sizeof(buf
));
1252 strlcat(buf
, FORMAT_MATCHES
, sizeof(buf
));
1253 proc
= proc_create_data(buf
, 0440, net
->proc_net
, &xt_match_ops
,
1254 (void *)(unsigned long)af
);
1256 goto out_remove_tables
;
1257 if (uid_valid(root_uid
) && gid_valid(root_gid
))
1258 proc_set_user(proc
, root_uid
, root_gid
);
1260 strlcpy(buf
, xt_prefix
[af
], sizeof(buf
));
1261 strlcat(buf
, FORMAT_TARGETS
, sizeof(buf
));
1262 proc
= proc_create_data(buf
, 0440, net
->proc_net
, &xt_target_ops
,
1263 (void *)(unsigned long)af
);
1265 goto out_remove_matches
;
1266 if (uid_valid(root_uid
) && gid_valid(root_gid
))
1267 proc_set_user(proc
, root_uid
, root_gid
);
1272 #ifdef CONFIG_PROC_FS
1274 strlcpy(buf
, xt_prefix
[af
], sizeof(buf
));
1275 strlcat(buf
, FORMAT_MATCHES
, sizeof(buf
));
1276 remove_proc_entry(buf
, net
->proc_net
);
1279 strlcpy(buf
, xt_prefix
[af
], sizeof(buf
));
1280 strlcat(buf
, FORMAT_TABLES
, sizeof(buf
));
1281 remove_proc_entry(buf
, net
->proc_net
);
1286 EXPORT_SYMBOL_GPL(xt_proto_init
);
1288 void xt_proto_fini(struct net
*net
, u_int8_t af
)
1290 #ifdef CONFIG_PROC_FS
1291 char buf
[XT_FUNCTION_MAXNAMELEN
];
1293 strlcpy(buf
, xt_prefix
[af
], sizeof(buf
));
1294 strlcat(buf
, FORMAT_TABLES
, sizeof(buf
));
1295 remove_proc_entry(buf
, net
->proc_net
);
1297 strlcpy(buf
, xt_prefix
[af
], sizeof(buf
));
1298 strlcat(buf
, FORMAT_TARGETS
, sizeof(buf
));
1299 remove_proc_entry(buf
, net
->proc_net
);
1301 strlcpy(buf
, xt_prefix
[af
], sizeof(buf
));
1302 strlcat(buf
, FORMAT_MATCHES
, sizeof(buf
));
1303 remove_proc_entry(buf
, net
->proc_net
);
1304 #endif /*CONFIG_PROC_FS*/
1306 EXPORT_SYMBOL_GPL(xt_proto_fini
);
1308 static int __net_init
xt_net_init(struct net
*net
)
1312 for (i
= 0; i
< NFPROTO_NUMPROTO
; i
++)
1313 INIT_LIST_HEAD(&net
->xt
.tables
[i
]);
1317 static struct pernet_operations xt_net_ops
= {
1318 .init
= xt_net_init
,
1321 static int __init
xt_init(void)
1326 for_each_possible_cpu(i
) {
1327 seqcount_init(&per_cpu(xt_recseq
, i
));
1330 xt
= kmalloc(sizeof(struct xt_af
) * NFPROTO_NUMPROTO
, GFP_KERNEL
);
1334 for (i
= 0; i
< NFPROTO_NUMPROTO
; i
++) {
1335 mutex_init(&xt
[i
].mutex
);
1336 #ifdef CONFIG_COMPAT
1337 mutex_init(&xt
[i
].compat_mutex
);
1338 xt
[i
].compat_tab
= NULL
;
1340 INIT_LIST_HEAD(&xt
[i
].target
);
1341 INIT_LIST_HEAD(&xt
[i
].match
);
1343 rv
= register_pernet_subsys(&xt_net_ops
);
1349 static void __exit
xt_fini(void)
1351 unregister_pernet_subsys(&xt_net_ops
);
1355 module_init(xt_init
);
1356 module_exit(xt_fini
);