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>
29 static int ipv6_pkt_to_tuple(const struct sk_buff
*skb
, unsigned int nhoff
,
30 struct nf_conntrack_tuple
*tuple
)
32 u_int32_t _addrs
[8], *ap
;
34 ap
= skb_header_pointer(skb
, nhoff
+ offsetof(struct ipv6hdr
, saddr
),
35 sizeof(_addrs
), _addrs
);
39 memcpy(tuple
->src
.u3
.ip6
, ap
, sizeof(tuple
->src
.u3
.ip6
));
40 memcpy(tuple
->dst
.u3
.ip6
, ap
+ 4, sizeof(tuple
->dst
.u3
.ip6
));
45 static int ipv6_invert_tuple(struct nf_conntrack_tuple
*tuple
,
46 const struct nf_conntrack_tuple
*orig
)
48 memcpy(tuple
->src
.u3
.ip6
, orig
->dst
.u3
.ip6
, sizeof(tuple
->src
.u3
.ip6
));
49 memcpy(tuple
->dst
.u3
.ip6
, orig
->src
.u3
.ip6
, sizeof(tuple
->dst
.u3
.ip6
));
54 static int ipv6_print_tuple(struct seq_file
*s
,
55 const struct nf_conntrack_tuple
*tuple
)
57 return seq_printf(s
, "src=" NIP6_FMT
" dst=" NIP6_FMT
" ",
58 NIP6(*((struct in6_addr
*)tuple
->src
.u3
.ip6
)),
59 NIP6(*((struct in6_addr
*)tuple
->dst
.u3
.ip6
)));
62 static int ipv6_print_conntrack(struct seq_file
*s
,
63 const struct nf_conn
*conntrack
)
69 * Based on ipv6_skip_exthdr() in net/ipv6/exthdr.c
71 * This function parses (probably truncated) exthdr set "hdr"
72 * of length "len". "nexthdrp" initially points to some place,
73 * where type of the first header can be found.
75 * It skips all well-known exthdrs, and returns pointer to the start
76 * of unparsable area i.e. the first header with unknown type.
77 * if success, *nexthdr is updated by type/protocol of this header.
79 * NOTES: - it may return pointer pointing beyond end of packet,
80 * if the last recognized header is truncated in the middle.
81 * - if packet is truncated, so that all parsed headers are skipped,
83 * - if packet is fragmented, return pointer of the fragment header.
84 * - ESP is unparsable for now and considered like
85 * normal payload protocol.
86 * - Note also special handling of AUTH header. Thanks to IPsec wizards.
89 static int nf_ct_ipv6_skip_exthdr(const struct sk_buff
*skb
, int start
,
90 u8
*nexthdrp
, int len
)
92 u8 nexthdr
= *nexthdrp
;
94 while (ipv6_ext_hdr(nexthdr
)) {
95 struct ipv6_opt_hdr hdr
;
98 if (len
< (int)sizeof(struct ipv6_opt_hdr
))
100 if (nexthdr
== NEXTHDR_NONE
)
102 if (nexthdr
== NEXTHDR_FRAGMENT
)
104 if (skb_copy_bits(skb
, start
, &hdr
, sizeof(hdr
)))
106 if (nexthdr
== NEXTHDR_AUTH
)
107 hdrlen
= (hdr
.hdrlen
+2)<<2;
109 hdrlen
= ipv6_optlen(&hdr
);
111 nexthdr
= hdr
.nexthdr
;
120 static int ipv6_get_l4proto(const struct sk_buff
*skb
, unsigned int nhoff
,
121 unsigned int *dataoff
, u_int8_t
*protonum
)
123 unsigned int extoff
= nhoff
+ sizeof(struct ipv6hdr
);
127 if (skb_copy_bits(skb
, nhoff
+ offsetof(struct ipv6hdr
, nexthdr
),
128 &pnum
, sizeof(pnum
)) != 0) {
129 pr_debug("ip6_conntrack_core: can't get nexthdr\n");
132 protoff
= nf_ct_ipv6_skip_exthdr(skb
, extoff
, &pnum
, skb
->len
- extoff
);
134 * (protoff == skb->len) mean that the packet doesn't have no data
135 * except of IPv6 & ext headers. but it's tracked anyway. - YK
137 if ((protoff
< 0) || (protoff
> skb
->len
)) {
138 pr_debug("ip6_conntrack_core: can't find proto in pkt\n");
147 static unsigned int ipv6_confirm(unsigned int hooknum
,
148 struct sk_buff
**pskb
,
149 const struct net_device
*in
,
150 const struct net_device
*out
,
151 int (*okfn
)(struct sk_buff
*))
154 struct nf_conn_help
*help
;
155 struct nf_conntrack_helper
*helper
;
156 enum ip_conntrack_info ctinfo
;
157 unsigned int ret
, protoff
;
158 unsigned int extoff
= (u8
*)(ipv6_hdr(*pskb
) + 1) - (*pskb
)->data
;
159 unsigned char pnum
= ipv6_hdr(*pskb
)->nexthdr
;
162 /* This is where we call the helper: as the packet goes out. */
163 ct
= nf_ct_get(*pskb
, &ctinfo
);
164 if (!ct
|| ctinfo
== IP_CT_RELATED
+ IP_CT_IS_REPLY
)
167 help
= nfct_help(ct
);
170 /* rcu_read_lock()ed by nf_hook_slow */
171 helper
= rcu_dereference(help
->helper
);
175 protoff
= nf_ct_ipv6_skip_exthdr(*pskb
, extoff
, &pnum
,
176 (*pskb
)->len
- extoff
);
177 if (protoff
> (*pskb
)->len
|| pnum
== NEXTHDR_FRAGMENT
) {
178 pr_debug("proto header not found\n");
182 ret
= helper
->help(pskb
, protoff
, ct
, ctinfo
);
183 if (ret
!= NF_ACCEPT
)
186 /* We've seen it coming out the other side: confirm it */
187 return nf_conntrack_confirm(pskb
);
190 static unsigned int ipv6_defrag(unsigned int hooknum
,
191 struct sk_buff
**pskb
,
192 const struct net_device
*in
,
193 const struct net_device
*out
,
194 int (*okfn
)(struct sk_buff
*))
196 struct sk_buff
*reasm
;
198 /* Previously seen (loopback)? */
202 reasm
= nf_ct_frag6_gather(*pskb
);
208 /* error occured or not fragmented */
212 nf_ct_frag6_output(hooknum
, reasm
, (struct net_device
*)in
,
213 (struct net_device
*)out
, okfn
);
218 static unsigned int ipv6_conntrack_in(unsigned int hooknum
,
219 struct sk_buff
**pskb
,
220 const struct net_device
*in
,
221 const struct net_device
*out
,
222 int (*okfn
)(struct sk_buff
*))
224 struct sk_buff
*reasm
= (*pskb
)->nfct_reasm
;
226 /* This packet is fragmented and has reassembled packet. */
228 /* Reassembled packet isn't parsed yet ? */
232 ret
= nf_conntrack_in(PF_INET6
, hooknum
, &reasm
);
233 if (ret
!= NF_ACCEPT
)
236 nf_conntrack_get(reasm
->nfct
);
237 (*pskb
)->nfct
= reasm
->nfct
;
238 (*pskb
)->nfctinfo
= reasm
->nfctinfo
;
242 return nf_conntrack_in(PF_INET6
, hooknum
, pskb
);
245 static unsigned int ipv6_conntrack_local(unsigned int hooknum
,
246 struct sk_buff
**pskb
,
247 const struct net_device
*in
,
248 const struct net_device
*out
,
249 int (*okfn
)(struct sk_buff
*))
251 /* root is playing with raw sockets. */
252 if ((*pskb
)->len
< sizeof(struct ipv6hdr
)) {
254 printk("ipv6_conntrack_local: packet too short\n");
257 return ipv6_conntrack_in(hooknum
, pskb
, in
, out
, okfn
);
260 static struct nf_hook_ops ipv6_conntrack_ops
[] = {
263 .owner
= THIS_MODULE
,
265 .hooknum
= NF_IP6_PRE_ROUTING
,
266 .priority
= NF_IP6_PRI_CONNTRACK_DEFRAG
,
269 .hook
= ipv6_conntrack_in
,
270 .owner
= THIS_MODULE
,
272 .hooknum
= NF_IP6_PRE_ROUTING
,
273 .priority
= NF_IP6_PRI_CONNTRACK
,
276 .hook
= ipv6_conntrack_local
,
277 .owner
= THIS_MODULE
,
279 .hooknum
= NF_IP6_LOCAL_OUT
,
280 .priority
= NF_IP6_PRI_CONNTRACK
,
284 .owner
= THIS_MODULE
,
286 .hooknum
= NF_IP6_LOCAL_OUT
,
287 .priority
= NF_IP6_PRI_CONNTRACK_DEFRAG
,
290 .hook
= ipv6_confirm
,
291 .owner
= THIS_MODULE
,
293 .hooknum
= NF_IP6_POST_ROUTING
,
294 .priority
= NF_IP6_PRI_LAST
,
297 .hook
= ipv6_confirm
,
298 .owner
= THIS_MODULE
,
300 .hooknum
= NF_IP6_LOCAL_IN
,
301 .priority
= NF_IP6_PRI_LAST
-1,
306 static ctl_table nf_ct_ipv6_sysctl_table
[] = {
308 .ctl_name
= NET_NF_CONNTRACK_FRAG6_TIMEOUT
,
309 .procname
= "nf_conntrack_frag6_timeout",
310 .data
= &nf_ct_frag6_timeout
,
311 .maxlen
= sizeof(unsigned int),
313 .proc_handler
= &proc_dointvec_jiffies
,
316 .ctl_name
= NET_NF_CONNTRACK_FRAG6_LOW_THRESH
,
317 .procname
= "nf_conntrack_frag6_low_thresh",
318 .data
= &nf_ct_frag6_low_thresh
,
319 .maxlen
= sizeof(unsigned int),
321 .proc_handler
= &proc_dointvec
,
324 .ctl_name
= NET_NF_CONNTRACK_FRAG6_HIGH_THRESH
,
325 .procname
= "nf_conntrack_frag6_high_thresh",
326 .data
= &nf_ct_frag6_high_thresh
,
327 .maxlen
= sizeof(unsigned int),
329 .proc_handler
= &proc_dointvec
,
335 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
337 #include <linux/netfilter/nfnetlink.h>
338 #include <linux/netfilter/nfnetlink_conntrack.h>
340 static int ipv6_tuple_to_nfattr(struct sk_buff
*skb
,
341 const struct nf_conntrack_tuple
*tuple
)
343 NFA_PUT(skb
, CTA_IP_V6_SRC
, sizeof(u_int32_t
) * 4,
345 NFA_PUT(skb
, CTA_IP_V6_DST
, sizeof(u_int32_t
) * 4,
353 static const size_t cta_min_ip
[CTA_IP_MAX
] = {
354 [CTA_IP_V6_SRC
-1] = sizeof(u_int32_t
)*4,
355 [CTA_IP_V6_DST
-1] = sizeof(u_int32_t
)*4,
358 static int ipv6_nfattr_to_tuple(struct nfattr
*tb
[],
359 struct nf_conntrack_tuple
*t
)
361 if (!tb
[CTA_IP_V6_SRC
-1] || !tb
[CTA_IP_V6_DST
-1])
364 if (nfattr_bad_size(tb
, CTA_IP_MAX
, cta_min_ip
))
367 memcpy(&t
->src
.u3
.ip6
, NFA_DATA(tb
[CTA_IP_V6_SRC
-1]),
368 sizeof(u_int32_t
) * 4);
369 memcpy(&t
->dst
.u3
.ip6
, NFA_DATA(tb
[CTA_IP_V6_DST
-1]),
370 sizeof(u_int32_t
) * 4);
376 struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 __read_mostly
= {
379 .pkt_to_tuple
= ipv6_pkt_to_tuple
,
380 .invert_tuple
= ipv6_invert_tuple
,
381 .print_tuple
= ipv6_print_tuple
,
382 .print_conntrack
= ipv6_print_conntrack
,
383 .get_l4proto
= ipv6_get_l4proto
,
384 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
385 .tuple_to_nfattr
= ipv6_tuple_to_nfattr
,
386 .nfattr_to_tuple
= ipv6_nfattr_to_tuple
,
389 .ctl_table_path
= nf_net_netfilter_sysctl_path
,
390 .ctl_table
= nf_ct_ipv6_sysctl_table
,
395 MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6
));
396 MODULE_LICENSE("GPL");
397 MODULE_AUTHOR("Yasuyuki KOZAKAI @USAGI <yasuyuki.kozakai@toshiba.co.jp>");
399 static int __init
nf_conntrack_l3proto_ipv6_init(void)
405 ret
= nf_ct_frag6_init();
407 printk("nf_conntrack_ipv6: can't initialize frag6.\n");
410 ret
= nf_conntrack_l4proto_register(&nf_conntrack_l4proto_tcp6
);
412 printk("nf_conntrack_ipv6: can't register tcp.\n");
416 ret
= nf_conntrack_l4proto_register(&nf_conntrack_l4proto_udp6
);
418 printk("nf_conntrack_ipv6: can't register udp.\n");
422 ret
= nf_conntrack_l4proto_register(&nf_conntrack_l4proto_icmpv6
);
424 printk("nf_conntrack_ipv6: can't register icmpv6.\n");
428 ret
= nf_conntrack_l3proto_register(&nf_conntrack_l3proto_ipv6
);
430 printk("nf_conntrack_ipv6: can't register ipv6\n");
434 ret
= nf_register_hooks(ipv6_conntrack_ops
,
435 ARRAY_SIZE(ipv6_conntrack_ops
));
437 printk("nf_conntrack_ipv6: can't register pre-routing defrag "
444 nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6
);
446 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6
);
448 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6
);
450 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6
);
452 nf_ct_frag6_cleanup();
456 static void __exit
nf_conntrack_l3proto_ipv6_fini(void)
459 nf_unregister_hooks(ipv6_conntrack_ops
, ARRAY_SIZE(ipv6_conntrack_ops
));
460 nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6
);
461 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6
);
462 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6
);
463 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6
);
464 nf_ct_frag6_cleanup();
467 module_init(nf_conntrack_l3proto_ipv6_init
);
468 module_exit(nf_conntrack_l3proto_ipv6_fini
);