2 * Copyright (C)2004 USAGI/WIDE Project
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
9 * Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
12 #include <linux/types.h>
13 #include <linux/ipv6.h>
14 #include <linux/in6.h>
15 #include <linux/netfilter.h>
16 #include <linux/module.h>
17 #include <linux/skbuff.h>
18 #include <linux/icmp.h>
19 #include <linux/sysctl.h>
22 #include <linux/netfilter_ipv6.h>
23 #include <net/netfilter/nf_conntrack.h>
24 #include <net/netfilter/nf_conntrack_helper.h>
25 #include <net/netfilter/nf_conntrack_l4proto.h>
26 #include <net/netfilter/nf_conntrack_l3proto.h>
27 #include <net/netfilter/nf_conntrack_core.h>
32 #define DEBUGP(format, args...)
35 static int ipv6_pkt_to_tuple(const struct sk_buff
*skb
, unsigned int nhoff
,
36 struct nf_conntrack_tuple
*tuple
)
38 u_int32_t _addrs
[8], *ap
;
40 ap
= skb_header_pointer(skb
, nhoff
+ offsetof(struct ipv6hdr
, saddr
),
41 sizeof(_addrs
), _addrs
);
45 memcpy(tuple
->src
.u3
.ip6
, ap
, sizeof(tuple
->src
.u3
.ip6
));
46 memcpy(tuple
->dst
.u3
.ip6
, ap
+ 4, sizeof(tuple
->dst
.u3
.ip6
));
51 static int ipv6_invert_tuple(struct nf_conntrack_tuple
*tuple
,
52 const struct nf_conntrack_tuple
*orig
)
54 memcpy(tuple
->src
.u3
.ip6
, orig
->dst
.u3
.ip6
, sizeof(tuple
->src
.u3
.ip6
));
55 memcpy(tuple
->dst
.u3
.ip6
, orig
->src
.u3
.ip6
, sizeof(tuple
->dst
.u3
.ip6
));
60 static int ipv6_print_tuple(struct seq_file
*s
,
61 const struct nf_conntrack_tuple
*tuple
)
63 return seq_printf(s
, "src=" NIP6_FMT
" dst=" NIP6_FMT
" ",
64 NIP6(*((struct in6_addr
*)tuple
->src
.u3
.ip6
)),
65 NIP6(*((struct in6_addr
*)tuple
->dst
.u3
.ip6
)));
68 static int ipv6_print_conntrack(struct seq_file
*s
,
69 const struct nf_conn
*conntrack
)
75 * Based on ipv6_skip_exthdr() in net/ipv6/exthdr.c
77 * This function parses (probably truncated) exthdr set "hdr"
78 * of length "len". "nexthdrp" initially points to some place,
79 * where type of the first header can be found.
81 * It skips all well-known exthdrs, and returns pointer to the start
82 * of unparsable area i.e. the first header with unknown type.
83 * if success, *nexthdr is updated by type/protocol of this header.
85 * NOTES: - it may return pointer pointing beyond end of packet,
86 * if the last recognized header is truncated in the middle.
87 * - if packet is truncated, so that all parsed headers are skipped,
89 * - if packet is fragmented, return pointer of the fragment header.
90 * - ESP is unparsable for now and considered like
91 * normal payload protocol.
92 * - Note also special handling of AUTH header. Thanks to IPsec wizards.
95 int nf_ct_ipv6_skip_exthdr(struct sk_buff
*skb
, int start
, u8
*nexthdrp
,
98 u8 nexthdr
= *nexthdrp
;
100 while (ipv6_ext_hdr(nexthdr
)) {
101 struct ipv6_opt_hdr hdr
;
104 if (len
< (int)sizeof(struct ipv6_opt_hdr
))
106 if (nexthdr
== NEXTHDR_NONE
)
108 if (nexthdr
== NEXTHDR_FRAGMENT
)
110 if (skb_copy_bits(skb
, start
, &hdr
, sizeof(hdr
)))
112 if (nexthdr
== NEXTHDR_AUTH
)
113 hdrlen
= (hdr
.hdrlen
+2)<<2;
115 hdrlen
= ipv6_optlen(&hdr
);
117 nexthdr
= hdr
.nexthdr
;
127 ipv6_prepare(struct sk_buff
**pskb
, unsigned int hooknum
, unsigned int *dataoff
,
130 unsigned int extoff
= (u8
*)(ipv6_hdr(*pskb
) + 1) - (*pskb
)->data
;
131 unsigned char pnum
= ipv6_hdr(*pskb
)->nexthdr
;
132 int protoff
= nf_ct_ipv6_skip_exthdr(*pskb
, extoff
, &pnum
,
133 (*pskb
)->len
- extoff
);
135 * (protoff == (*pskb)->len) mean that the packet doesn't have no data
136 * except of IPv6 & ext headers. but it's tracked anyway. - YK
138 if ((protoff
< 0) || (protoff
> (*pskb
)->len
)) {
139 DEBUGP("ip6_conntrack_core: can't find proto in pkt\n");
140 NF_CT_STAT_INC_ATOMIC(error
);
141 NF_CT_STAT_INC_ATOMIC(invalid
);
150 static unsigned int ipv6_confirm(unsigned int hooknum
,
151 struct sk_buff
**pskb
,
152 const struct net_device
*in
,
153 const struct net_device
*out
,
154 int (*okfn
)(struct sk_buff
*))
157 struct nf_conn_help
*help
;
158 struct nf_conntrack_helper
*helper
;
159 enum ip_conntrack_info ctinfo
;
160 unsigned int ret
, protoff
;
161 unsigned int extoff
= (u8
*)(ipv6_hdr(*pskb
) + 1) - (*pskb
)->data
;
162 unsigned char pnum
= ipv6_hdr(*pskb
)->nexthdr
;
165 /* This is where we call the helper: as the packet goes out. */
166 ct
= nf_ct_get(*pskb
, &ctinfo
);
167 if (!ct
|| ctinfo
== IP_CT_RELATED
+ IP_CT_IS_REPLY
)
170 help
= nfct_help(ct
);
173 /* rcu_read_lock()ed by nf_hook_slow */
174 helper
= rcu_dereference(help
->helper
);
178 protoff
= nf_ct_ipv6_skip_exthdr(*pskb
, extoff
, &pnum
,
179 (*pskb
)->len
- extoff
);
180 if (protoff
> (*pskb
)->len
|| pnum
== NEXTHDR_FRAGMENT
) {
181 DEBUGP("proto header not found\n");
185 ret
= helper
->help(pskb
, protoff
, ct
, ctinfo
);
186 if (ret
!= NF_ACCEPT
)
189 /* We've seen it coming out the other side: confirm it */
190 return nf_conntrack_confirm(pskb
);
193 static unsigned int ipv6_defrag(unsigned int hooknum
,
194 struct sk_buff
**pskb
,
195 const struct net_device
*in
,
196 const struct net_device
*out
,
197 int (*okfn
)(struct sk_buff
*))
199 struct sk_buff
*reasm
;
201 /* Previously seen (loopback)? */
205 reasm
= nf_ct_frag6_gather(*pskb
);
211 /* error occured or not fragmented */
215 nf_ct_frag6_output(hooknum
, reasm
, (struct net_device
*)in
,
216 (struct net_device
*)out
, okfn
);
221 static unsigned int ipv6_conntrack_in(unsigned int hooknum
,
222 struct sk_buff
**pskb
,
223 const struct net_device
*in
,
224 const struct net_device
*out
,
225 int (*okfn
)(struct sk_buff
*))
227 struct sk_buff
*reasm
= (*pskb
)->nfct_reasm
;
229 /* This packet is fragmented and has reassembled packet. */
231 /* Reassembled packet isn't parsed yet ? */
235 ret
= nf_conntrack_in(PF_INET6
, hooknum
, &reasm
);
236 if (ret
!= NF_ACCEPT
)
239 nf_conntrack_get(reasm
->nfct
);
240 (*pskb
)->nfct
= reasm
->nfct
;
241 (*pskb
)->nfctinfo
= reasm
->nfctinfo
;
245 return nf_conntrack_in(PF_INET6
, hooknum
, pskb
);
248 static unsigned int ipv6_conntrack_local(unsigned int hooknum
,
249 struct sk_buff
**pskb
,
250 const struct net_device
*in
,
251 const struct net_device
*out
,
252 int (*okfn
)(struct sk_buff
*))
254 /* root is playing with raw sockets. */
255 if ((*pskb
)->len
< sizeof(struct ipv6hdr
)) {
257 printk("ipv6_conntrack_local: packet too short\n");
260 return ipv6_conntrack_in(hooknum
, pskb
, in
, out
, okfn
);
263 static struct nf_hook_ops ipv6_conntrack_ops
[] = {
266 .owner
= THIS_MODULE
,
268 .hooknum
= NF_IP6_PRE_ROUTING
,
269 .priority
= NF_IP6_PRI_CONNTRACK_DEFRAG
,
272 .hook
= ipv6_conntrack_in
,
273 .owner
= THIS_MODULE
,
275 .hooknum
= NF_IP6_PRE_ROUTING
,
276 .priority
= NF_IP6_PRI_CONNTRACK
,
279 .hook
= ipv6_conntrack_local
,
280 .owner
= THIS_MODULE
,
282 .hooknum
= NF_IP6_LOCAL_OUT
,
283 .priority
= NF_IP6_PRI_CONNTRACK
,
287 .owner
= THIS_MODULE
,
289 .hooknum
= NF_IP6_LOCAL_OUT
,
290 .priority
= NF_IP6_PRI_CONNTRACK_DEFRAG
,
293 .hook
= ipv6_confirm
,
294 .owner
= THIS_MODULE
,
296 .hooknum
= NF_IP6_POST_ROUTING
,
297 .priority
= NF_IP6_PRI_LAST
,
300 .hook
= ipv6_confirm
,
301 .owner
= THIS_MODULE
,
303 .hooknum
= NF_IP6_LOCAL_IN
,
304 .priority
= NF_IP6_PRI_LAST
-1,
309 static ctl_table nf_ct_ipv6_sysctl_table
[] = {
311 .ctl_name
= NET_NF_CONNTRACK_FRAG6_TIMEOUT
,
312 .procname
= "nf_conntrack_frag6_timeout",
313 .data
= &nf_ct_frag6_timeout
,
314 .maxlen
= sizeof(unsigned int),
316 .proc_handler
= &proc_dointvec_jiffies
,
319 .ctl_name
= NET_NF_CONNTRACK_FRAG6_LOW_THRESH
,
320 .procname
= "nf_conntrack_frag6_low_thresh",
321 .data
= &nf_ct_frag6_low_thresh
,
322 .maxlen
= sizeof(unsigned int),
324 .proc_handler
= &proc_dointvec
,
327 .ctl_name
= NET_NF_CONNTRACK_FRAG6_HIGH_THRESH
,
328 .procname
= "nf_conntrack_frag6_high_thresh",
329 .data
= &nf_ct_frag6_high_thresh
,
330 .maxlen
= sizeof(unsigned int),
332 .proc_handler
= &proc_dointvec
,
338 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
340 #include <linux/netfilter/nfnetlink.h>
341 #include <linux/netfilter/nfnetlink_conntrack.h>
343 static int ipv6_tuple_to_nfattr(struct sk_buff
*skb
,
344 const struct nf_conntrack_tuple
*tuple
)
346 NFA_PUT(skb
, CTA_IP_V6_SRC
, sizeof(u_int32_t
) * 4,
348 NFA_PUT(skb
, CTA_IP_V6_DST
, sizeof(u_int32_t
) * 4,
356 static const size_t cta_min_ip
[CTA_IP_MAX
] = {
357 [CTA_IP_V6_SRC
-1] = sizeof(u_int32_t
)*4,
358 [CTA_IP_V6_DST
-1] = sizeof(u_int32_t
)*4,
361 static int ipv6_nfattr_to_tuple(struct nfattr
*tb
[],
362 struct nf_conntrack_tuple
*t
)
364 if (!tb
[CTA_IP_V6_SRC
-1] || !tb
[CTA_IP_V6_DST
-1])
367 if (nfattr_bad_size(tb
, CTA_IP_MAX
, cta_min_ip
))
370 memcpy(&t
->src
.u3
.ip6
, NFA_DATA(tb
[CTA_IP_V6_SRC
-1]),
371 sizeof(u_int32_t
) * 4);
372 memcpy(&t
->dst
.u3
.ip6
, NFA_DATA(tb
[CTA_IP_V6_DST
-1]),
373 sizeof(u_int32_t
) * 4);
379 struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6
= {
382 .pkt_to_tuple
= ipv6_pkt_to_tuple
,
383 .invert_tuple
= ipv6_invert_tuple
,
384 .print_tuple
= ipv6_print_tuple
,
385 .print_conntrack
= ipv6_print_conntrack
,
386 .prepare
= ipv6_prepare
,
387 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
388 .tuple_to_nfattr
= ipv6_tuple_to_nfattr
,
389 .nfattr_to_tuple
= ipv6_nfattr_to_tuple
,
392 .ctl_table_path
= nf_net_netfilter_sysctl_path
,
393 .ctl_table
= nf_ct_ipv6_sysctl_table
,
398 MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6
));
399 MODULE_LICENSE("GPL");
400 MODULE_AUTHOR("Yasuyuki KOZAKAI @USAGI <yasuyuki.kozakai@toshiba.co.jp>");
402 static int __init
nf_conntrack_l3proto_ipv6_init(void)
408 ret
= nf_ct_frag6_init();
410 printk("nf_conntrack_ipv6: can't initialize frag6.\n");
413 ret
= nf_conntrack_l4proto_register(&nf_conntrack_l4proto_tcp6
);
415 printk("nf_conntrack_ipv6: can't register tcp.\n");
419 ret
= nf_conntrack_l4proto_register(&nf_conntrack_l4proto_udp6
);
421 printk("nf_conntrack_ipv6: can't register udp.\n");
425 ret
= nf_conntrack_l4proto_register(&nf_conntrack_l4proto_icmpv6
);
427 printk("nf_conntrack_ipv6: can't register icmpv6.\n");
431 ret
= nf_conntrack_l3proto_register(&nf_conntrack_l3proto_ipv6
);
433 printk("nf_conntrack_ipv6: can't register ipv6\n");
437 ret
= nf_register_hooks(ipv6_conntrack_ops
,
438 ARRAY_SIZE(ipv6_conntrack_ops
));
440 printk("nf_conntrack_ipv6: can't register pre-routing defrag "
447 nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6
);
449 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6
);
451 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6
);
453 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6
);
455 nf_ct_frag6_cleanup();
459 static void __exit
nf_conntrack_l3proto_ipv6_fini(void)
462 nf_unregister_hooks(ipv6_conntrack_ops
, ARRAY_SIZE(ipv6_conntrack_ops
));
463 nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6
);
464 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6
);
465 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6
);
466 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6
);
467 nf_ct_frag6_cleanup();
470 module_init(nf_conntrack_l3proto_ipv6_init
);
471 module_exit(nf_conntrack_l3proto_ipv6_fini
);