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>
21 #include <net/inet_frag.h>
23 #include <linux/netfilter_ipv6.h>
24 #include <net/netfilter/nf_conntrack.h>
25 #include <net/netfilter/nf_conntrack_helper.h>
26 #include <net/netfilter/nf_conntrack_l4proto.h>
27 #include <net/netfilter/nf_conntrack_l3proto.h>
28 #include <net/netfilter/nf_conntrack_core.h>
30 static int ipv6_pkt_to_tuple(const struct sk_buff
*skb
, unsigned int nhoff
,
31 struct nf_conntrack_tuple
*tuple
)
33 u_int32_t _addrs
[8], *ap
;
35 ap
= skb_header_pointer(skb
, nhoff
+ offsetof(struct ipv6hdr
, saddr
),
36 sizeof(_addrs
), _addrs
);
40 memcpy(tuple
->src
.u3
.ip6
, ap
, sizeof(tuple
->src
.u3
.ip6
));
41 memcpy(tuple
->dst
.u3
.ip6
, ap
+ 4, sizeof(tuple
->dst
.u3
.ip6
));
46 static int ipv6_invert_tuple(struct nf_conntrack_tuple
*tuple
,
47 const struct nf_conntrack_tuple
*orig
)
49 memcpy(tuple
->src
.u3
.ip6
, orig
->dst
.u3
.ip6
, sizeof(tuple
->src
.u3
.ip6
));
50 memcpy(tuple
->dst
.u3
.ip6
, orig
->src
.u3
.ip6
, sizeof(tuple
->dst
.u3
.ip6
));
55 static int ipv6_print_tuple(struct seq_file
*s
,
56 const struct nf_conntrack_tuple
*tuple
)
58 return seq_printf(s
, "src=" NIP6_FMT
" dst=" NIP6_FMT
" ",
59 NIP6(*((struct in6_addr
*)tuple
->src
.u3
.ip6
)),
60 NIP6(*((struct in6_addr
*)tuple
->dst
.u3
.ip6
)));
63 static int ipv6_print_conntrack(struct seq_file
*s
,
64 const struct nf_conn
*conntrack
)
70 * Based on ipv6_skip_exthdr() in net/ipv6/exthdr.c
72 * This function parses (probably truncated) exthdr set "hdr"
73 * of length "len". "nexthdrp" initially points to some place,
74 * where type of the first header can be found.
76 * It skips all well-known exthdrs, and returns pointer to the start
77 * of unparsable area i.e. the first header with unknown type.
78 * if success, *nexthdr is updated by type/protocol of this header.
80 * NOTES: - it may return pointer pointing beyond end of packet,
81 * if the last recognized header is truncated in the middle.
82 * - if packet is truncated, so that all parsed headers are skipped,
84 * - if packet is fragmented, return pointer of the fragment header.
85 * - ESP is unparsable for now and considered like
86 * normal payload protocol.
87 * - Note also special handling of AUTH header. Thanks to IPsec wizards.
90 static int nf_ct_ipv6_skip_exthdr(const struct sk_buff
*skb
, int start
,
91 u8
*nexthdrp
, int len
)
93 u8 nexthdr
= *nexthdrp
;
95 while (ipv6_ext_hdr(nexthdr
)) {
96 struct ipv6_opt_hdr hdr
;
99 if (len
< (int)sizeof(struct ipv6_opt_hdr
))
101 if (nexthdr
== NEXTHDR_NONE
)
103 if (nexthdr
== NEXTHDR_FRAGMENT
)
105 if (skb_copy_bits(skb
, start
, &hdr
, sizeof(hdr
)))
107 if (nexthdr
== NEXTHDR_AUTH
)
108 hdrlen
= (hdr
.hdrlen
+2)<<2;
110 hdrlen
= ipv6_optlen(&hdr
);
112 nexthdr
= hdr
.nexthdr
;
121 static int ipv6_get_l4proto(const struct sk_buff
*skb
, unsigned int nhoff
,
122 unsigned int *dataoff
, u_int8_t
*protonum
)
124 unsigned int extoff
= nhoff
+ sizeof(struct ipv6hdr
);
128 if (skb_copy_bits(skb
, nhoff
+ offsetof(struct ipv6hdr
, nexthdr
),
129 &pnum
, sizeof(pnum
)) != 0) {
130 pr_debug("ip6_conntrack_core: can't get nexthdr\n");
133 protoff
= nf_ct_ipv6_skip_exthdr(skb
, extoff
, &pnum
, skb
->len
- extoff
);
135 * (protoff == skb->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
> skb
->len
)) {
139 pr_debug("ip6_conntrack_core: can't find proto in pkt\n");
148 static unsigned int ipv6_confirm(unsigned int hooknum
,
150 const struct net_device
*in
,
151 const struct net_device
*out
,
152 int (*okfn
)(struct sk_buff
*))
155 struct nf_conn_help
*help
;
156 struct nf_conntrack_helper
*helper
;
157 enum ip_conntrack_info ctinfo
;
158 unsigned int ret
, protoff
;
159 unsigned int extoff
= (u8
*)(ipv6_hdr(skb
) + 1) - skb
->data
;
160 unsigned char pnum
= ipv6_hdr(skb
)->nexthdr
;
163 /* This is where we call the helper: as the packet goes out. */
164 ct
= nf_ct_get(skb
, &ctinfo
);
165 if (!ct
|| ctinfo
== IP_CT_RELATED
+ IP_CT_IS_REPLY
)
168 help
= nfct_help(ct
);
171 /* rcu_read_lock()ed by nf_hook_slow */
172 helper
= rcu_dereference(help
->helper
);
176 protoff
= nf_ct_ipv6_skip_exthdr(skb
, extoff
, &pnum
,
178 if (protoff
> skb
->len
|| pnum
== NEXTHDR_FRAGMENT
) {
179 pr_debug("proto header not found\n");
183 ret
= helper
->help(skb
, protoff
, ct
, ctinfo
);
184 if (ret
!= NF_ACCEPT
)
187 /* We've seen it coming out the other side: confirm it */
188 return nf_conntrack_confirm(skb
);
191 static unsigned int ipv6_defrag(unsigned int hooknum
,
193 const struct net_device
*in
,
194 const struct net_device
*out
,
195 int (*okfn
)(struct sk_buff
*))
197 struct sk_buff
*reasm
;
199 /* Previously seen (loopback)? */
203 reasm
= nf_ct_frag6_gather(skb
);
209 /* error occured or not fragmented */
213 nf_ct_frag6_output(hooknum
, reasm
, (struct net_device
*)in
,
214 (struct net_device
*)out
, okfn
);
219 static unsigned int ipv6_conntrack_in(unsigned int hooknum
,
221 const struct net_device
*in
,
222 const struct net_device
*out
,
223 int (*okfn
)(struct sk_buff
*))
225 struct sk_buff
*reasm
= skb
->nfct_reasm
;
227 /* This packet is fragmented and has reassembled packet. */
229 /* Reassembled packet isn't parsed yet ? */
233 ret
= nf_conntrack_in(PF_INET6
, hooknum
, reasm
);
234 if (ret
!= NF_ACCEPT
)
237 nf_conntrack_get(reasm
->nfct
);
238 skb
->nfct
= reasm
->nfct
;
239 skb
->nfctinfo
= reasm
->nfctinfo
;
243 return nf_conntrack_in(PF_INET6
, hooknum
, skb
);
246 static unsigned int ipv6_conntrack_local(unsigned int hooknum
,
248 const struct net_device
*in
,
249 const struct net_device
*out
,
250 int (*okfn
)(struct sk_buff
*))
252 /* root is playing with raw sockets. */
253 if (skb
->len
< sizeof(struct ipv6hdr
)) {
255 printk("ipv6_conntrack_local: packet too short\n");
258 return ipv6_conntrack_in(hooknum
, skb
, in
, out
, okfn
);
261 static struct nf_hook_ops ipv6_conntrack_ops
[] = {
264 .owner
= THIS_MODULE
,
266 .hooknum
= NF_IP6_PRE_ROUTING
,
267 .priority
= NF_IP6_PRI_CONNTRACK_DEFRAG
,
270 .hook
= ipv6_conntrack_in
,
271 .owner
= THIS_MODULE
,
273 .hooknum
= NF_IP6_PRE_ROUTING
,
274 .priority
= NF_IP6_PRI_CONNTRACK
,
277 .hook
= ipv6_conntrack_local
,
278 .owner
= THIS_MODULE
,
280 .hooknum
= NF_IP6_LOCAL_OUT
,
281 .priority
= NF_IP6_PRI_CONNTRACK
,
285 .owner
= THIS_MODULE
,
287 .hooknum
= NF_IP6_LOCAL_OUT
,
288 .priority
= NF_IP6_PRI_CONNTRACK_DEFRAG
,
291 .hook
= ipv6_confirm
,
292 .owner
= THIS_MODULE
,
294 .hooknum
= NF_IP6_POST_ROUTING
,
295 .priority
= NF_IP6_PRI_LAST
,
298 .hook
= ipv6_confirm
,
299 .owner
= THIS_MODULE
,
301 .hooknum
= NF_IP6_LOCAL_IN
,
302 .priority
= NF_IP6_PRI_LAST
-1,
307 static ctl_table nf_ct_ipv6_sysctl_table
[] = {
309 .procname
= "nf_conntrack_frag6_timeout",
310 .data
= &nf_frags_ctl
.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_frags_ctl
.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_frags_ctl
.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_nlattr(struct sk_buff
*skb
,
341 const struct nf_conntrack_tuple
*tuple
)
343 NLA_PUT(skb
, CTA_IP_V6_SRC
, sizeof(u_int32_t
) * 4,
345 NLA_PUT(skb
, CTA_IP_V6_DST
, sizeof(u_int32_t
) * 4,
353 static const struct nla_policy ipv6_nla_policy
[CTA_IP_MAX
+1] = {
354 [CTA_IP_V6_SRC
] = { .len
= sizeof(u_int32_t
)*4 },
355 [CTA_IP_V6_DST
] = { .len
= sizeof(u_int32_t
)*4 },
358 static int ipv6_nlattr_to_tuple(struct nlattr
*tb
[],
359 struct nf_conntrack_tuple
*t
)
361 if (!tb
[CTA_IP_V6_SRC
] || !tb
[CTA_IP_V6_DST
])
364 memcpy(&t
->src
.u3
.ip6
, nla_data(tb
[CTA_IP_V6_SRC
]),
365 sizeof(u_int32_t
) * 4);
366 memcpy(&t
->dst
.u3
.ip6
, nla_data(tb
[CTA_IP_V6_DST
]),
367 sizeof(u_int32_t
) * 4);
373 struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 __read_mostly
= {
376 .pkt_to_tuple
= ipv6_pkt_to_tuple
,
377 .invert_tuple
= ipv6_invert_tuple
,
378 .print_tuple
= ipv6_print_tuple
,
379 .print_conntrack
= ipv6_print_conntrack
,
380 .get_l4proto
= ipv6_get_l4proto
,
381 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
382 .tuple_to_nlattr
= ipv6_tuple_to_nlattr
,
383 .nlattr_to_tuple
= ipv6_nlattr_to_tuple
,
384 .nla_policy
= ipv6_nla_policy
,
387 .ctl_table_path
= nf_net_netfilter_sysctl_path
,
388 .ctl_table
= nf_ct_ipv6_sysctl_table
,
393 MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6
));
394 MODULE_LICENSE("GPL");
395 MODULE_AUTHOR("Yasuyuki KOZAKAI @USAGI <yasuyuki.kozakai@toshiba.co.jp>");
397 static int __init
nf_conntrack_l3proto_ipv6_init(void)
403 ret
= nf_ct_frag6_init();
405 printk("nf_conntrack_ipv6: can't initialize frag6.\n");
408 ret
= nf_conntrack_l4proto_register(&nf_conntrack_l4proto_tcp6
);
410 printk("nf_conntrack_ipv6: can't register tcp.\n");
414 ret
= nf_conntrack_l4proto_register(&nf_conntrack_l4proto_udp6
);
416 printk("nf_conntrack_ipv6: can't register udp.\n");
420 ret
= nf_conntrack_l4proto_register(&nf_conntrack_l4proto_icmpv6
);
422 printk("nf_conntrack_ipv6: can't register icmpv6.\n");
426 ret
= nf_conntrack_l3proto_register(&nf_conntrack_l3proto_ipv6
);
428 printk("nf_conntrack_ipv6: can't register ipv6\n");
432 ret
= nf_register_hooks(ipv6_conntrack_ops
,
433 ARRAY_SIZE(ipv6_conntrack_ops
));
435 printk("nf_conntrack_ipv6: can't register pre-routing defrag "
442 nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6
);
444 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6
);
446 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6
);
448 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6
);
450 nf_ct_frag6_cleanup();
454 static void __exit
nf_conntrack_l3proto_ipv6_fini(void)
457 nf_unregister_hooks(ipv6_conntrack_ops
, ARRAY_SIZE(ipv6_conntrack_ops
));
458 nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6
);
459 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6
);
460 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6
);
461 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6
);
462 nf_ct_frag6_cleanup();
465 module_init(nf_conntrack_l3proto_ipv6_init
);
466 module_exit(nf_conntrack_l3proto_ipv6_fini
);