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>
20 #include <net/inet_frag.h>
22 #include <linux/netfilter_bridge.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>
29 #include <net/netfilter/nf_conntrack_zones.h>
30 #include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
31 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
32 #include <net/netfilter/nf_log.h>
34 static bool ipv6_pkt_to_tuple(const struct sk_buff
*skb
, unsigned int nhoff
,
35 struct nf_conntrack_tuple
*tuple
)
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 bool 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=%pI6 dst=%pI6 ",
64 tuple
->src
.u3
.ip6
, tuple
->dst
.u3
.ip6
);
68 * Based on ipv6_skip_exthdr() in net/ipv6/exthdr.c
70 * This function parses (probably truncated) exthdr set "hdr"
71 * of length "len". "nexthdrp" initially points to some place,
72 * where type of the first header can be found.
74 * It skips all well-known exthdrs, and returns pointer to the start
75 * of unparsable area i.e. the first header with unknown type.
76 * if success, *nexthdr is updated by type/protocol of this header.
78 * NOTES: - it may return pointer pointing beyond end of packet,
79 * if the last recognized header is truncated in the middle.
80 * - if packet is truncated, so that all parsed headers are skipped,
82 * - if packet is fragmented, return pointer of the fragment header.
83 * - ESP is unparsable for now and considered like
84 * normal payload protocol.
85 * - Note also special handling of AUTH header. Thanks to IPsec wizards.
88 static int nf_ct_ipv6_skip_exthdr(const struct sk_buff
*skb
, int start
,
89 u8
*nexthdrp
, int len
)
91 u8 nexthdr
= *nexthdrp
;
93 while (ipv6_ext_hdr(nexthdr
)) {
94 struct ipv6_opt_hdr hdr
;
97 if (len
< (int)sizeof(struct ipv6_opt_hdr
))
99 if (nexthdr
== NEXTHDR_NONE
)
101 if (nexthdr
== NEXTHDR_FRAGMENT
)
103 if (skb_copy_bits(skb
, start
, &hdr
, sizeof(hdr
)))
105 if (nexthdr
== NEXTHDR_AUTH
)
106 hdrlen
= (hdr
.hdrlen
+2)<<2;
108 hdrlen
= ipv6_optlen(&hdr
);
110 nexthdr
= hdr
.nexthdr
;
119 static int ipv6_get_l4proto(const struct sk_buff
*skb
, unsigned int nhoff
,
120 unsigned int *dataoff
, u_int8_t
*protonum
)
122 unsigned int extoff
= nhoff
+ sizeof(struct ipv6hdr
);
126 if (skb_copy_bits(skb
, nhoff
+ offsetof(struct ipv6hdr
, nexthdr
),
127 &pnum
, sizeof(pnum
)) != 0) {
128 pr_debug("ip6_conntrack_core: can't get nexthdr\n");
131 protoff
= nf_ct_ipv6_skip_exthdr(skb
, extoff
, &pnum
, skb
->len
- extoff
);
133 * (protoff == skb->len) mean that the packet doesn't have no data
134 * except of IPv6 & ext headers. but it's tracked anyway. - YK
136 if ((protoff
< 0) || (protoff
> skb
->len
)) {
137 pr_debug("ip6_conntrack_core: can't find proto in pkt\n");
146 static unsigned int ipv6_confirm(unsigned int hooknum
,
148 const struct net_device
*in
,
149 const struct net_device
*out
,
150 int (*okfn
)(struct sk_buff
*))
153 const struct nf_conn_help
*help
;
154 const struct nf_conntrack_helper
*helper
;
155 enum ip_conntrack_info ctinfo
;
156 unsigned int ret
, protoff
;
157 unsigned int extoff
= (u8
*)(ipv6_hdr(skb
) + 1) - skb
->data
;
158 unsigned char pnum
= ipv6_hdr(skb
)->nexthdr
;
161 /* This is where we call the helper: as the packet goes out. */
162 ct
= nf_ct_get(skb
, &ctinfo
);
163 if (!ct
|| ctinfo
== IP_CT_RELATED_REPLY
)
166 help
= nfct_help(ct
);
169 /* rcu_read_lock()ed by nf_hook_slow */
170 helper
= rcu_dereference(help
->helper
);
174 protoff
= nf_ct_ipv6_skip_exthdr(skb
, extoff
, &pnum
,
176 if (protoff
> skb
->len
|| pnum
== NEXTHDR_FRAGMENT
) {
177 pr_debug("proto header not found\n");
181 ret
= helper
->help(skb
, protoff
, ct
, ctinfo
);
182 if (ret
!= NF_ACCEPT
) {
183 nf_log_packet(NFPROTO_IPV6
, hooknum
, skb
, in
, out
, NULL
,
184 "nf_ct_%s: dropping packet", helper
->name
);
188 /* We've seen it coming out the other side: confirm it */
189 return nf_conntrack_confirm(skb
);
192 static unsigned int __ipv6_conntrack_in(struct net
*net
,
193 unsigned int hooknum
,
195 int (*okfn
)(struct sk_buff
*))
197 struct sk_buff
*reasm
= skb
->nfct_reasm
;
199 /* This packet is fragmented and has reassembled packet. */
201 /* Reassembled packet isn't parsed yet ? */
205 ret
= nf_conntrack_in(net
, PF_INET6
, hooknum
, reasm
);
206 if (ret
!= NF_ACCEPT
)
209 nf_conntrack_get(reasm
->nfct
);
210 skb
->nfct
= reasm
->nfct
;
211 skb
->nfctinfo
= reasm
->nfctinfo
;
215 return nf_conntrack_in(net
, PF_INET6
, hooknum
, skb
);
218 static unsigned int ipv6_conntrack_in(unsigned int hooknum
,
220 const struct net_device
*in
,
221 const struct net_device
*out
,
222 int (*okfn
)(struct sk_buff
*))
224 return __ipv6_conntrack_in(dev_net(in
), hooknum
, skb
, okfn
);
227 static unsigned int ipv6_conntrack_local(unsigned int hooknum
,
229 const struct net_device
*in
,
230 const struct net_device
*out
,
231 int (*okfn
)(struct sk_buff
*))
233 /* root is playing with raw sockets. */
234 if (skb
->len
< sizeof(struct ipv6hdr
)) {
236 pr_notice("ipv6_conntrack_local: packet too short\n");
239 return __ipv6_conntrack_in(dev_net(out
), hooknum
, skb
, okfn
);
242 static struct nf_hook_ops ipv6_conntrack_ops
[] __read_mostly
= {
244 .hook
= ipv6_conntrack_in
,
245 .owner
= THIS_MODULE
,
247 .hooknum
= NF_INET_PRE_ROUTING
,
248 .priority
= NF_IP6_PRI_CONNTRACK
,
251 .hook
= ipv6_conntrack_local
,
252 .owner
= THIS_MODULE
,
254 .hooknum
= NF_INET_LOCAL_OUT
,
255 .priority
= NF_IP6_PRI_CONNTRACK
,
258 .hook
= ipv6_confirm
,
259 .owner
= THIS_MODULE
,
261 .hooknum
= NF_INET_POST_ROUTING
,
262 .priority
= NF_IP6_PRI_LAST
,
265 .hook
= ipv6_confirm
,
266 .owner
= THIS_MODULE
,
268 .hooknum
= NF_INET_LOCAL_IN
,
269 .priority
= NF_IP6_PRI_LAST
-1,
273 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
275 #include <linux/netfilter/nfnetlink.h>
276 #include <linux/netfilter/nfnetlink_conntrack.h>
278 static int ipv6_tuple_to_nlattr(struct sk_buff
*skb
,
279 const struct nf_conntrack_tuple
*tuple
)
281 NLA_PUT(skb
, CTA_IP_V6_SRC
, sizeof(u_int32_t
) * 4,
283 NLA_PUT(skb
, CTA_IP_V6_DST
, sizeof(u_int32_t
) * 4,
291 static const struct nla_policy ipv6_nla_policy
[CTA_IP_MAX
+1] = {
292 [CTA_IP_V6_SRC
] = { .len
= sizeof(u_int32_t
)*4 },
293 [CTA_IP_V6_DST
] = { .len
= sizeof(u_int32_t
)*4 },
296 static int ipv6_nlattr_to_tuple(struct nlattr
*tb
[],
297 struct nf_conntrack_tuple
*t
)
299 if (!tb
[CTA_IP_V6_SRC
] || !tb
[CTA_IP_V6_DST
])
302 memcpy(&t
->src
.u3
.ip6
, nla_data(tb
[CTA_IP_V6_SRC
]),
303 sizeof(u_int32_t
) * 4);
304 memcpy(&t
->dst
.u3
.ip6
, nla_data(tb
[CTA_IP_V6_DST
]),
305 sizeof(u_int32_t
) * 4);
310 static int ipv6_nlattr_tuple_size(void)
312 return nla_policy_len(ipv6_nla_policy
, CTA_IP_MAX
+ 1);
316 struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 __read_mostly
= {
319 .pkt_to_tuple
= ipv6_pkt_to_tuple
,
320 .invert_tuple
= ipv6_invert_tuple
,
321 .print_tuple
= ipv6_print_tuple
,
322 .get_l4proto
= ipv6_get_l4proto
,
323 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
324 .tuple_to_nlattr
= ipv6_tuple_to_nlattr
,
325 .nlattr_tuple_size
= ipv6_nlattr_tuple_size
,
326 .nlattr_to_tuple
= ipv6_nlattr_to_tuple
,
327 .nla_policy
= ipv6_nla_policy
,
332 MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6
));
333 MODULE_LICENSE("GPL");
334 MODULE_AUTHOR("Yasuyuki KOZAKAI @USAGI <yasuyuki.kozakai@toshiba.co.jp>");
336 static int __init
nf_conntrack_l3proto_ipv6_init(void)
341 nf_defrag_ipv6_enable();
343 ret
= nf_conntrack_l4proto_register(&nf_conntrack_l4proto_tcp6
);
345 pr_err("nf_conntrack_ipv6: can't register tcp.\n");
349 ret
= nf_conntrack_l4proto_register(&nf_conntrack_l4proto_udp6
);
351 pr_err("nf_conntrack_ipv6: can't register udp.\n");
355 ret
= nf_conntrack_l4proto_register(&nf_conntrack_l4proto_icmpv6
);
357 pr_err("nf_conntrack_ipv6: can't register icmpv6.\n");
361 ret
= nf_conntrack_l3proto_register(&nf_conntrack_l3proto_ipv6
);
363 pr_err("nf_conntrack_ipv6: can't register ipv6\n");
367 ret
= nf_register_hooks(ipv6_conntrack_ops
,
368 ARRAY_SIZE(ipv6_conntrack_ops
));
370 pr_err("nf_conntrack_ipv6: can't register pre-routing defrag "
377 nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6
);
379 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6
);
381 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6
);
383 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6
);
387 static void __exit
nf_conntrack_l3proto_ipv6_fini(void)
390 nf_unregister_hooks(ipv6_conntrack_ops
, ARRAY_SIZE(ipv6_conntrack_ops
));
391 nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6
);
392 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6
);
393 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6
);
394 nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6
);
397 module_init(nf_conntrack_l3proto_ipv6_init
);
398 module_exit(nf_conntrack_l3proto_ipv6_fini
);