1 /* NAT for netfilter; shared with compatibility layer. */
3 /* (C) 1999-2001 Paul `Rusty' Russell
4 * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
11 #include <linux/module.h>
12 #include <linux/types.h>
13 #include <linux/timer.h>
14 #include <linux/skbuff.h>
15 #include <linux/vmalloc.h>
16 #include <net/checksum.h>
19 #include <net/tcp.h> /* For tcp_prot in getorigdst */
20 #include <linux/icmp.h>
21 #include <linux/udp.h>
22 #include <linux/jhash.h>
24 #include <linux/netfilter_ipv4.h>
25 #include <net/netfilter/nf_conntrack.h>
26 #include <net/netfilter/nf_conntrack_core.h>
27 #include <net/netfilter/nf_nat.h>
28 #include <net/netfilter/nf_nat_protocol.h>
29 #include <net/netfilter/nf_nat_core.h>
30 #include <net/netfilter/nf_nat_helper.h>
31 #include <net/netfilter/nf_conntrack_helper.h>
32 #include <net/netfilter/nf_conntrack_l3proto.h>
33 #include <net/netfilter/nf_conntrack_l4proto.h>
38 #define DEBUGP(format, args...)
41 static DEFINE_RWLOCK(nf_nat_lock
);
43 static struct nf_conntrack_l3proto
*l3proto
= NULL
;
45 /* Calculated at init based on memory size */
46 static unsigned int nf_nat_htable_size
;
48 static struct list_head
*bysource
;
50 #define MAX_IP_NAT_PROTO 256
51 static struct nf_nat_protocol
*nf_nat_protos
[MAX_IP_NAT_PROTO
];
53 static inline struct nf_nat_protocol
*
54 __nf_nat_proto_find(u_int8_t protonum
)
56 return rcu_dereference(nf_nat_protos
[protonum
]);
59 struct nf_nat_protocol
*
60 nf_nat_proto_find_get(u_int8_t protonum
)
62 struct nf_nat_protocol
*p
;
65 p
= __nf_nat_proto_find(protonum
);
66 if (!try_module_get(p
->me
))
67 p
= &nf_nat_unknown_protocol
;
72 EXPORT_SYMBOL_GPL(nf_nat_proto_find_get
);
75 nf_nat_proto_put(struct nf_nat_protocol
*p
)
79 EXPORT_SYMBOL_GPL(nf_nat_proto_put
);
81 /* We keep an extra hash for each conntrack, for fast searching. */
82 static inline unsigned int
83 hash_by_src(const struct nf_conntrack_tuple
*tuple
)
85 /* Original src, to ensure we map it consistently if poss. */
86 return jhash_3words((__force u32
)tuple
->src
.u3
.ip
, tuple
->src
.u
.all
,
87 tuple
->dst
.protonum
, 0) % nf_nat_htable_size
;
90 /* Noone using conntrack by the time this called. */
91 static void nf_nat_cleanup_conntrack(struct nf_conn
*conn
)
93 struct nf_conn_nat
*nat
;
94 if (!(conn
->status
& IPS_NAT_DONE_MASK
))
98 write_lock_bh(&nf_nat_lock
);
99 list_del(&nat
->info
.bysource
);
101 write_unlock_bh(&nf_nat_lock
);
104 /* Is this tuple already taken? (not by us) */
106 nf_nat_used_tuple(const struct nf_conntrack_tuple
*tuple
,
107 const struct nf_conn
*ignored_conntrack
)
109 /* Conntrack tracking doesn't keep track of outgoing tuples; only
110 incoming ones. NAT means they don't have a fixed mapping,
111 so we invert the tuple and look for the incoming reply.
113 We could keep a separate hash if this proves too slow. */
114 struct nf_conntrack_tuple reply
;
116 nf_ct_invert_tuplepr(&reply
, tuple
);
117 return nf_conntrack_tuple_taken(&reply
, ignored_conntrack
);
119 EXPORT_SYMBOL(nf_nat_used_tuple
);
121 /* If we source map this tuple so reply looks like reply_tuple, will
122 * that meet the constraints of range. */
124 in_range(const struct nf_conntrack_tuple
*tuple
,
125 const struct nf_nat_range
*range
)
127 struct nf_nat_protocol
*proto
;
130 /* If we are supposed to map IPs, then we must be in the
131 range specified, otherwise let this drag us onto a new src IP. */
132 if (range
->flags
& IP_NAT_RANGE_MAP_IPS
) {
133 if (ntohl(tuple
->src
.u3
.ip
) < ntohl(range
->min_ip
) ||
134 ntohl(tuple
->src
.u3
.ip
) > ntohl(range
->max_ip
))
139 proto
= __nf_nat_proto_find(tuple
->dst
.protonum
);
140 if (!(range
->flags
& IP_NAT_RANGE_PROTO_SPECIFIED
) ||
141 proto
->in_range(tuple
, IP_NAT_MANIP_SRC
,
142 &range
->min
, &range
->max
))
150 same_src(const struct nf_conn
*ct
,
151 const struct nf_conntrack_tuple
*tuple
)
153 const struct nf_conntrack_tuple
*t
;
155 t
= &ct
->tuplehash
[IP_CT_DIR_ORIGINAL
].tuple
;
156 return (t
->dst
.protonum
== tuple
->dst
.protonum
&&
157 t
->src
.u3
.ip
== tuple
->src
.u3
.ip
&&
158 t
->src
.u
.all
== tuple
->src
.u
.all
);
161 /* Only called for SRC manip */
163 find_appropriate_src(const struct nf_conntrack_tuple
*tuple
,
164 struct nf_conntrack_tuple
*result
,
165 const struct nf_nat_range
*range
)
167 unsigned int h
= hash_by_src(tuple
);
168 struct nf_conn_nat
*nat
;
171 read_lock_bh(&nf_nat_lock
);
172 list_for_each_entry(nat
, &bysource
[h
], info
.bysource
) {
174 if (same_src(ct
, tuple
)) {
175 /* Copy source part from reply tuple. */
176 nf_ct_invert_tuplepr(result
,
177 &ct
->tuplehash
[IP_CT_DIR_REPLY
].tuple
);
178 result
->dst
= tuple
->dst
;
180 if (in_range(result
, range
)) {
181 read_unlock_bh(&nf_nat_lock
);
186 read_unlock_bh(&nf_nat_lock
);
190 /* For [FUTURE] fragmentation handling, we want the least-used
191 src-ip/dst-ip/proto triple. Fairness doesn't come into it. Thus
192 if the range specifies 1.2.3.4 ports 10000-10005 and 1.2.3.5 ports
193 1-65535, we don't do pro-rata allocation based on ports; we choose
194 the ip with the lowest src-ip/dst-ip/proto usage.
197 find_best_ips_proto(struct nf_conntrack_tuple
*tuple
,
198 const struct nf_nat_range
*range
,
199 const struct nf_conn
*ct
,
200 enum nf_nat_manip_type maniptype
)
204 u_int32_t minip
, maxip
, j
;
206 /* No IP mapping? Do nothing. */
207 if (!(range
->flags
& IP_NAT_RANGE_MAP_IPS
))
210 if (maniptype
== IP_NAT_MANIP_SRC
)
211 var_ipp
= &tuple
->src
.u3
.ip
;
213 var_ipp
= &tuple
->dst
.u3
.ip
;
215 /* Fast path: only one choice. */
216 if (range
->min_ip
== range
->max_ip
) {
217 *var_ipp
= range
->min_ip
;
221 /* Hashing source and destination IPs gives a fairly even
222 * spread in practice (if there are a small number of IPs
223 * involved, there usually aren't that many connections
224 * anyway). The consistency means that servers see the same
225 * client coming from the same IP (some Internet Banking sites
226 * like this), even across reboots. */
227 minip
= ntohl(range
->min_ip
);
228 maxip
= ntohl(range
->max_ip
);
229 j
= jhash_2words((__force u32
)tuple
->src
.u3
.ip
,
230 (__force u32
)tuple
->dst
.u3
.ip
, 0);
231 *var_ipp
= htonl(minip
+ j
% (maxip
- minip
+ 1));
234 /* Manipulate the tuple into the range given. For NF_IP_POST_ROUTING,
235 * we change the source to map into the range. For NF_IP_PRE_ROUTING
236 * and NF_IP_LOCAL_OUT, we change the destination to map into the
237 * range. It might not be possible to get a unique tuple, but we try.
238 * At worst (or if we race), we will end up with a final duplicate in
239 * __ip_conntrack_confirm and drop the packet. */
241 get_unique_tuple(struct nf_conntrack_tuple
*tuple
,
242 const struct nf_conntrack_tuple
*orig_tuple
,
243 const struct nf_nat_range
*range
,
245 enum nf_nat_manip_type maniptype
)
247 struct nf_nat_protocol
*proto
;
249 /* 1) If this srcip/proto/src-proto-part is currently mapped,
250 and that same mapping gives a unique tuple within the given
253 This is only required for source (ie. NAT/masq) mappings.
254 So far, we don't do local source mappings, so multiple
255 manips not an issue. */
256 if (maniptype
== IP_NAT_MANIP_SRC
) {
257 if (find_appropriate_src(orig_tuple
, tuple
, range
)) {
258 DEBUGP("get_unique_tuple: Found current src map\n");
259 if (!(range
->flags
& IP_NAT_RANGE_PROTO_RANDOM
))
260 if (!nf_nat_used_tuple(tuple
, ct
))
265 /* 2) Select the least-used IP/proto combination in the given
267 *tuple
= *orig_tuple
;
268 find_best_ips_proto(tuple
, range
, ct
, maniptype
);
270 /* 3) The per-protocol part of the manip is made to map into
271 the range to make a unique tuple. */
274 proto
= __nf_nat_proto_find(orig_tuple
->dst
.protonum
);
276 /* Change protocol info to have some randomization */
277 if (range
->flags
& IP_NAT_RANGE_PROTO_RANDOM
) {
278 proto
->unique_tuple(tuple
, range
, maniptype
, ct
);
282 /* Only bother mapping if it's not already in range and unique */
283 if ((!(range
->flags
& IP_NAT_RANGE_PROTO_SPECIFIED
) ||
284 proto
->in_range(tuple
, maniptype
, &range
->min
, &range
->max
)) &&
285 !nf_nat_used_tuple(tuple
, ct
))
288 /* Last change: get protocol to try to obtain unique tuple. */
289 proto
->unique_tuple(tuple
, range
, maniptype
, ct
);
295 nf_nat_setup_info(struct nf_conn
*ct
,
296 const struct nf_nat_range
*range
,
297 unsigned int hooknum
)
299 struct nf_conntrack_tuple curr_tuple
, new_tuple
;
300 struct nf_conn_nat
*nat
;
301 struct nf_nat_info
*info
;
302 int have_to_hash
= !(ct
->status
& IPS_NAT_DONE_MASK
);
303 enum nf_nat_manip_type maniptype
= HOOK2MANIP(hooknum
);
305 /* nat helper or nfctnetlink also setup binding */
308 nat
= nf_ct_ext_add(ct
, NF_CT_EXT_NAT
, GFP_ATOMIC
);
310 DEBUGP("failed to add NAT extension\n");
315 NF_CT_ASSERT(hooknum
== NF_IP_PRE_ROUTING
||
316 hooknum
== NF_IP_POST_ROUTING
||
317 hooknum
== NF_IP_LOCAL_IN
||
318 hooknum
== NF_IP_LOCAL_OUT
);
319 BUG_ON(nf_nat_initialized(ct
, maniptype
));
321 /* What we've got will look like inverse of reply. Normally
322 this is what is in the conntrack, except for prior
323 manipulations (future optimization: if num_manips == 0,
325 conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple) */
326 nf_ct_invert_tuplepr(&curr_tuple
,
327 &ct
->tuplehash
[IP_CT_DIR_REPLY
].tuple
);
329 get_unique_tuple(&new_tuple
, &curr_tuple
, range
, ct
, maniptype
);
331 if (!nf_ct_tuple_equal(&new_tuple
, &curr_tuple
)) {
332 struct nf_conntrack_tuple reply
;
334 /* Alter conntrack table so will recognize replies. */
335 nf_ct_invert_tuplepr(&reply
, &new_tuple
);
336 nf_conntrack_alter_reply(ct
, &reply
);
338 /* Non-atomic: we own this at the moment. */
339 if (maniptype
== IP_NAT_MANIP_SRC
)
340 ct
->status
|= IPS_SRC_NAT
;
342 ct
->status
|= IPS_DST_NAT
;
345 /* Place in source hash if this is the first time. */
347 unsigned int srchash
;
349 srchash
= hash_by_src(&ct
->tuplehash
[IP_CT_DIR_ORIGINAL
].tuple
);
350 write_lock_bh(&nf_nat_lock
);
351 /* nf_conntrack_alter_reply might re-allocate exntension aera */
352 info
= &nfct_nat(ct
)->info
;
354 list_add(&info
->bysource
, &bysource
[srchash
]);
355 write_unlock_bh(&nf_nat_lock
);
359 if (maniptype
== IP_NAT_MANIP_DST
)
360 set_bit(IPS_DST_NAT_DONE_BIT
, &ct
->status
);
362 set_bit(IPS_SRC_NAT_DONE_BIT
, &ct
->status
);
366 EXPORT_SYMBOL(nf_nat_setup_info
);
368 /* Returns true if succeeded. */
370 manip_pkt(u_int16_t proto
,
371 struct sk_buff
**pskb
,
372 unsigned int iphdroff
,
373 const struct nf_conntrack_tuple
*target
,
374 enum nf_nat_manip_type maniptype
)
377 struct nf_nat_protocol
*p
;
379 if (!skb_make_writable(pskb
, iphdroff
+ sizeof(*iph
)))
382 iph
= (void *)(*pskb
)->data
+ iphdroff
;
384 /* Manipulate protcol part. */
386 /* rcu_read_lock()ed by nf_hook_slow */
387 p
= __nf_nat_proto_find(proto
);
388 if (!p
->manip_pkt(pskb
, iphdroff
, target
, maniptype
))
391 iph
= (void *)(*pskb
)->data
+ iphdroff
;
393 if (maniptype
== IP_NAT_MANIP_SRC
) {
394 nf_csum_replace4(&iph
->check
, iph
->saddr
, target
->src
.u3
.ip
);
395 iph
->saddr
= target
->src
.u3
.ip
;
397 nf_csum_replace4(&iph
->check
, iph
->daddr
, target
->dst
.u3
.ip
);
398 iph
->daddr
= target
->dst
.u3
.ip
;
403 /* Do packet manipulations according to nf_nat_setup_info. */
404 unsigned int nf_nat_packet(struct nf_conn
*ct
,
405 enum ip_conntrack_info ctinfo
,
406 unsigned int hooknum
,
407 struct sk_buff
**pskb
)
409 enum ip_conntrack_dir dir
= CTINFO2DIR(ctinfo
);
410 unsigned long statusbit
;
411 enum nf_nat_manip_type mtype
= HOOK2MANIP(hooknum
);
413 if (mtype
== IP_NAT_MANIP_SRC
)
414 statusbit
= IPS_SRC_NAT
;
416 statusbit
= IPS_DST_NAT
;
418 /* Invert if this is reply dir. */
419 if (dir
== IP_CT_DIR_REPLY
)
420 statusbit
^= IPS_NAT_MASK
;
422 /* Non-atomic: these bits don't change. */
423 if (ct
->status
& statusbit
) {
424 struct nf_conntrack_tuple target
;
426 /* We are aiming to look like inverse of other direction. */
427 nf_ct_invert_tuplepr(&target
, &ct
->tuplehash
[!dir
].tuple
);
429 if (!manip_pkt(target
.dst
.protonum
, pskb
, 0, &target
, mtype
))
434 EXPORT_SYMBOL_GPL(nf_nat_packet
);
436 /* Dir is direction ICMP is coming from (opposite to packet it contains) */
437 int nf_nat_icmp_reply_translation(struct nf_conn
*ct
,
438 enum ip_conntrack_info ctinfo
,
439 unsigned int hooknum
,
440 struct sk_buff
**pskb
)
446 struct nf_conntrack_l4proto
*l4proto
;
447 struct nf_conntrack_tuple inner
, target
;
448 int hdrlen
= ip_hdrlen(*pskb
);
449 enum ip_conntrack_dir dir
= CTINFO2DIR(ctinfo
);
450 unsigned long statusbit
;
451 enum nf_nat_manip_type manip
= HOOK2MANIP(hooknum
);
453 if (!skb_make_writable(pskb
, hdrlen
+ sizeof(*inside
)))
456 inside
= (void *)(*pskb
)->data
+ ip_hdrlen(*pskb
);
458 /* We're actually going to mangle it beyond trivial checksum
459 adjustment, so make sure the current checksum is correct. */
460 if (nf_ip_checksum(*pskb
, hooknum
, hdrlen
, 0))
463 /* Must be RELATED */
464 NF_CT_ASSERT((*pskb
)->nfctinfo
== IP_CT_RELATED
||
465 (*pskb
)->nfctinfo
== IP_CT_RELATED
+IP_CT_IS_REPLY
);
467 /* Redirects on non-null nats must be dropped, else they'll
468 start talking to each other without our translation, and be
470 if (inside
->icmp
.type
== ICMP_REDIRECT
) {
471 /* If NAT isn't finished, assume it and drop. */
472 if ((ct
->status
& IPS_NAT_DONE_MASK
) != IPS_NAT_DONE_MASK
)
475 if (ct
->status
& IPS_NAT_MASK
)
479 DEBUGP("icmp_reply_translation: translating error %p manp %u dir %s\n",
480 *pskb
, manip
, dir
== IP_CT_DIR_ORIGINAL
? "ORIG" : "REPLY");
482 /* rcu_read_lock()ed by nf_hook_slow */
483 l4proto
= __nf_ct_l4proto_find(PF_INET
, inside
->ip
.protocol
);
485 if (!nf_ct_get_tuple(*pskb
,
486 ip_hdrlen(*pskb
) + sizeof(struct icmphdr
),
488 sizeof(struct icmphdr
) + inside
->ip
.ihl
* 4),
491 &inner
, l3proto
, l4proto
))
494 /* Change inner back to look like incoming packet. We do the
495 opposite manip on this hook to normal, because it might not
496 pass all hooks (locally-generated ICMP). Consider incoming
497 packet: PREROUTING (DST manip), routing produces ICMP, goes
498 through POSTROUTING (which must correct the DST manip). */
499 if (!manip_pkt(inside
->ip
.protocol
, pskb
,
500 ip_hdrlen(*pskb
) + sizeof(inside
->icmp
),
501 &ct
->tuplehash
[!dir
].tuple
,
505 if ((*pskb
)->ip_summed
!= CHECKSUM_PARTIAL
) {
506 /* Reloading "inside" here since manip_pkt inner. */
507 inside
= (void *)(*pskb
)->data
+ ip_hdrlen(*pskb
);
508 inside
->icmp
.checksum
= 0;
509 inside
->icmp
.checksum
=
510 csum_fold(skb_checksum(*pskb
, hdrlen
,
511 (*pskb
)->len
- hdrlen
, 0));
514 /* Change outer to look the reply to an incoming packet
515 * (proto 0 means don't invert per-proto part). */
516 if (manip
== IP_NAT_MANIP_SRC
)
517 statusbit
= IPS_SRC_NAT
;
519 statusbit
= IPS_DST_NAT
;
521 /* Invert if this is reply dir. */
522 if (dir
== IP_CT_DIR_REPLY
)
523 statusbit
^= IPS_NAT_MASK
;
525 if (ct
->status
& statusbit
) {
526 nf_ct_invert_tuplepr(&target
, &ct
->tuplehash
[!dir
].tuple
);
527 if (!manip_pkt(0, pskb
, 0, &target
, manip
))
533 EXPORT_SYMBOL_GPL(nf_nat_icmp_reply_translation
);
535 /* Protocol registration. */
536 int nf_nat_protocol_register(struct nf_nat_protocol
*proto
)
540 write_lock_bh(&nf_nat_lock
);
541 if (nf_nat_protos
[proto
->protonum
] != &nf_nat_unknown_protocol
) {
545 rcu_assign_pointer(nf_nat_protos
[proto
->protonum
], proto
);
547 write_unlock_bh(&nf_nat_lock
);
550 EXPORT_SYMBOL(nf_nat_protocol_register
);
552 /* Noone stores the protocol anywhere; simply delete it. */
553 void nf_nat_protocol_unregister(struct nf_nat_protocol
*proto
)
555 write_lock_bh(&nf_nat_lock
);
556 rcu_assign_pointer(nf_nat_protos
[proto
->protonum
],
557 &nf_nat_unknown_protocol
);
558 write_unlock_bh(&nf_nat_lock
);
561 EXPORT_SYMBOL(nf_nat_protocol_unregister
);
563 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
565 nf_nat_port_range_to_nfattr(struct sk_buff
*skb
,
566 const struct nf_nat_range
*range
)
568 NFA_PUT(skb
, CTA_PROTONAT_PORT_MIN
, sizeof(__be16
),
569 &range
->min
.tcp
.port
);
570 NFA_PUT(skb
, CTA_PROTONAT_PORT_MAX
, sizeof(__be16
),
571 &range
->max
.tcp
.port
);
578 EXPORT_SYMBOL_GPL(nf_nat_port_nfattr_to_range
);
581 nf_nat_port_nfattr_to_range(struct nfattr
*tb
[], struct nf_nat_range
*range
)
585 /* we have to return whether we actually parsed something or not */
587 if (tb
[CTA_PROTONAT_PORT_MIN
-1]) {
589 range
->min
.tcp
.port
=
590 *(__be16
*)NFA_DATA(tb
[CTA_PROTONAT_PORT_MIN
-1]);
593 if (!tb
[CTA_PROTONAT_PORT_MAX
-1]) {
595 range
->max
.tcp
.port
= range
->min
.tcp
.port
;
598 range
->max
.tcp
.port
=
599 *(__be16
*)NFA_DATA(tb
[CTA_PROTONAT_PORT_MAX
-1]);
604 EXPORT_SYMBOL_GPL(nf_nat_port_range_to_nfattr
);
607 static void nf_nat_move_storage(struct nf_conn
*conntrack
, void *old
)
609 struct nf_conn_nat
*new_nat
= nf_ct_ext_find(conntrack
, NF_CT_EXT_NAT
);
610 struct nf_conn_nat
*old_nat
= (struct nf_conn_nat
*)old
;
611 struct nf_conn
*ct
= old_nat
->info
.ct
;
612 unsigned int srchash
;
614 if (!(ct
->status
& IPS_NAT_DONE_MASK
))
617 srchash
= hash_by_src(&ct
->tuplehash
[IP_CT_DIR_ORIGINAL
].tuple
);
619 write_lock_bh(&nf_nat_lock
);
620 list_replace(&old_nat
->info
.bysource
, &new_nat
->info
.bysource
);
621 new_nat
->info
.ct
= ct
;
622 write_unlock_bh(&nf_nat_lock
);
625 struct nf_ct_ext_type nat_extend
= {
626 .len
= sizeof(struct nf_conn_nat
),
627 .align
= __alignof__(struct nf_conn_nat
),
628 .move
= nf_nat_move_storage
,
630 .flags
= NF_CT_EXT_F_PREALLOC
,
633 static int __init
nf_nat_init(void)
638 ret
= nf_ct_extend_register(&nat_extend
);
640 printk(KERN_ERR
"nf_nat_core: Unable to register extension\n");
644 /* Leave them the same for the moment. */
645 nf_nat_htable_size
= nf_conntrack_htable_size
;
647 /* One vmalloc for both hash tables */
648 bysource
= vmalloc(sizeof(struct list_head
) * nf_nat_htable_size
);
654 /* Sew in builtin protocols. */
655 write_lock_bh(&nf_nat_lock
);
656 for (i
= 0; i
< MAX_IP_NAT_PROTO
; i
++)
657 rcu_assign_pointer(nf_nat_protos
[i
], &nf_nat_unknown_protocol
);
658 rcu_assign_pointer(nf_nat_protos
[IPPROTO_TCP
], &nf_nat_protocol_tcp
);
659 rcu_assign_pointer(nf_nat_protos
[IPPROTO_UDP
], &nf_nat_protocol_udp
);
660 rcu_assign_pointer(nf_nat_protos
[IPPROTO_ICMP
], &nf_nat_protocol_icmp
);
661 write_unlock_bh(&nf_nat_lock
);
663 for (i
= 0; i
< nf_nat_htable_size
; i
++) {
664 INIT_LIST_HEAD(&bysource
[i
]);
667 /* FIXME: Man, this is a hack. <SIGH> */
668 NF_CT_ASSERT(rcu_dereference(nf_conntrack_destroyed
) == NULL
);
669 rcu_assign_pointer(nf_conntrack_destroyed
, nf_nat_cleanup_conntrack
);
671 /* Initialize fake conntrack so that NAT will skip it */
672 nf_conntrack_untracked
.status
|= IPS_NAT_DONE_MASK
;
674 l3proto
= nf_ct_l3proto_find_get((u_int16_t
)AF_INET
);
678 nf_ct_extend_unregister(&nat_extend
);
682 /* Clear NAT section of all conntracks, in case we're loaded again. */
683 static int clean_nat(struct nf_conn
*i
, void *data
)
685 struct nf_conn_nat
*nat
= nfct_nat(i
);
689 memset(nat
, 0, sizeof(nat
));
690 i
->status
&= ~(IPS_NAT_MASK
| IPS_NAT_DONE_MASK
| IPS_SEQ_ADJUST
);
694 static void __exit
nf_nat_cleanup(void)
696 nf_ct_iterate_cleanup(&clean_nat
, NULL
);
697 rcu_assign_pointer(nf_conntrack_destroyed
, NULL
);
700 nf_ct_l3proto_put(l3proto
);
701 nf_ct_extend_unregister(&nat_extend
);
704 MODULE_LICENSE("GPL");
706 module_init(nf_nat_init
);
707 module_exit(nf_nat_cleanup
);