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 <linux/netfilter_ipv6/ip6_tables.h>
25 #include <net/netfilter/nf_conntrack.h>
26 #include <net/netfilter/nf_conntrack_helper.h>
27 #include <net/netfilter/nf_conntrack_l4proto.h>
28 #include <net/netfilter/nf_conntrack_l3proto.h>
29 #include <net/netfilter/nf_conntrack_core.h>
30 #include <net/netfilter/nf_conntrack_zones.h>
31 #include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
32 #include <net/netfilter/nf_nat_helper.h>
33 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
34 #include <net/netfilter/nf_log.h>
36 static bool ipv6_pkt_to_tuple(const struct sk_buff
*skb
, unsigned int nhoff
,
37 struct nf_conntrack_tuple
*tuple
)
42 ap
= skb_header_pointer(skb
, nhoff
+ offsetof(struct ipv6hdr
, saddr
),
43 sizeof(_addrs
), _addrs
);
47 memcpy(tuple
->src
.u3
.ip6
, ap
, sizeof(tuple
->src
.u3
.ip6
));
48 memcpy(tuple
->dst
.u3
.ip6
, ap
+ 4, sizeof(tuple
->dst
.u3
.ip6
));
53 static bool ipv6_invert_tuple(struct nf_conntrack_tuple
*tuple
,
54 const struct nf_conntrack_tuple
*orig
)
56 memcpy(tuple
->src
.u3
.ip6
, orig
->dst
.u3
.ip6
, sizeof(tuple
->src
.u3
.ip6
));
57 memcpy(tuple
->dst
.u3
.ip6
, orig
->src
.u3
.ip6
, sizeof(tuple
->dst
.u3
.ip6
));
62 static int ipv6_print_tuple(struct seq_file
*s
,
63 const struct nf_conntrack_tuple
*tuple
)
65 return seq_printf(s
, "src=%pI6 dst=%pI6 ",
66 tuple
->src
.u3
.ip6
, tuple
->dst
.u3
.ip6
);
69 static int ipv6_get_l4proto(const struct sk_buff
*skb
, unsigned int nhoff
,
70 unsigned int *dataoff
, u_int8_t
*protonum
)
72 unsigned int extoff
= nhoff
+ sizeof(struct ipv6hdr
);
77 if (skb_copy_bits(skb
, nhoff
+ offsetof(struct ipv6hdr
, nexthdr
),
78 &nexthdr
, sizeof(nexthdr
)) != 0) {
79 pr_debug("ip6_conntrack_core: can't get nexthdr\n");
82 protoff
= ipv6_skip_exthdr(skb
, extoff
, &nexthdr
, &frag_off
);
84 * (protoff == skb->len) means the packet has not data, just
85 * IPv6 and possibly extensions headers, but it is tracked anyway
87 if (protoff
< 0 || (frag_off
& htons(~0x7)) != 0) {
88 pr_debug("ip6_conntrack_core: can't find proto in pkt\n");
97 static unsigned int ipv6_helper(unsigned int hooknum
,
99 const struct net_device
*in
,
100 const struct net_device
*out
,
101 int (*okfn
)(struct sk_buff
*))
104 const struct nf_conn_help
*help
;
105 const struct nf_conntrack_helper
*helper
;
106 enum ip_conntrack_info ctinfo
;
112 /* This is where we call the helper: as the packet goes out. */
113 ct
= nf_ct_get(skb
, &ctinfo
);
114 if (!ct
|| ctinfo
== IP_CT_RELATED_REPLY
)
117 help
= nfct_help(ct
);
120 /* rcu_read_lock()ed by nf_hook_slow */
121 helper
= rcu_dereference(help
->helper
);
125 nexthdr
= ipv6_hdr(skb
)->nexthdr
;
126 protoff
= ipv6_skip_exthdr(skb
, sizeof(struct ipv6hdr
), &nexthdr
,
128 if (protoff
< 0 || (frag_off
& htons(~0x7)) != 0) {
129 pr_debug("proto header not found\n");
133 ret
= helper
->help(skb
, protoff
, ct
, ctinfo
);
134 if (ret
!= NF_ACCEPT
&& (ret
& NF_VERDICT_MASK
) != NF_QUEUE
) {
135 nf_log_packet(NFPROTO_IPV6
, hooknum
, skb
, in
, out
, NULL
,
136 "nf_ct_%s: dropping packet", helper
->name
);
141 static unsigned int ipv6_confirm(unsigned int hooknum
,
143 const struct net_device
*in
,
144 const struct net_device
*out
,
145 int (*okfn
)(struct sk_buff
*))
148 enum ip_conntrack_info ctinfo
;
149 unsigned char pnum
= ipv6_hdr(skb
)->nexthdr
;
153 ct
= nf_ct_get(skb
, &ctinfo
);
154 if (!ct
|| ctinfo
== IP_CT_RELATED_REPLY
)
157 protoff
= ipv6_skip_exthdr(skb
, sizeof(struct ipv6hdr
), &pnum
,
159 if (protoff
< 0 || (frag_off
& htons(~0x7)) != 0) {
160 pr_debug("proto header not found\n");
164 /* adjust seqs for loopback traffic only in outgoing direction */
165 if (test_bit(IPS_SEQ_ADJUST_BIT
, &ct
->status
) &&
166 !nf_is_loopback_packet(skb
)) {
167 typeof(nf_nat_seq_adjust_hook
) seq_adjust
;
169 seq_adjust
= rcu_dereference(nf_nat_seq_adjust_hook
);
171 !seq_adjust(skb
, ct
, ctinfo
, protoff
)) {
172 NF_CT_STAT_INC_ATOMIC(nf_ct_net(ct
), drop
);
177 /* We've seen it coming out the other side: confirm it */
178 return nf_conntrack_confirm(skb
);
181 static unsigned int __ipv6_conntrack_in(struct net
*net
,
182 unsigned int hooknum
,
184 const struct net_device
*in
,
185 const struct net_device
*out
,
186 int (*okfn
)(struct sk_buff
*))
188 struct sk_buff
*reasm
= skb
->nfct_reasm
;
189 const struct nf_conn_help
*help
;
191 enum ip_conntrack_info ctinfo
;
193 /* This packet is fragmented and has reassembled packet. */
195 /* Reassembled packet isn't parsed yet ? */
199 ret
= nf_conntrack_in(net
, PF_INET6
, hooknum
, reasm
);
200 if (ret
!= NF_ACCEPT
)
204 /* Conntrack helpers need the entire reassembled packet in the
205 * POST_ROUTING hook. In case of unconfirmed connections NAT
206 * might reassign a helper, so the entire packet is also
209 ct
= nf_ct_get(reasm
, &ctinfo
);
210 if (ct
!= NULL
&& !nf_ct_is_untracked(ct
)) {
211 help
= nfct_help(ct
);
212 if ((help
&& help
->helper
) || !nf_ct_is_confirmed(ct
)) {
213 nf_conntrack_get_reasm(skb
);
214 NF_HOOK_THRESH(NFPROTO_IPV6
, hooknum
, reasm
,
215 (struct net_device
*)in
,
216 (struct net_device
*)out
,
217 okfn
, NF_IP6_PRI_CONNTRACK
+ 1);
218 return NF_DROP_ERR(-ECANCELED
);
222 nf_conntrack_get(reasm
->nfct
);
223 skb
->nfct
= reasm
->nfct
;
224 skb
->nfctinfo
= reasm
->nfctinfo
;
228 return nf_conntrack_in(net
, PF_INET6
, hooknum
, skb
);
231 static unsigned int ipv6_conntrack_in(unsigned int hooknum
,
233 const struct net_device
*in
,
234 const struct net_device
*out
,
235 int (*okfn
)(struct sk_buff
*))
237 return __ipv6_conntrack_in(dev_net(in
), hooknum
, skb
, in
, out
, okfn
);
240 static unsigned int ipv6_conntrack_local(unsigned int hooknum
,
242 const struct net_device
*in
,
243 const struct net_device
*out
,
244 int (*okfn
)(struct sk_buff
*))
246 /* root is playing with raw sockets. */
247 if (skb
->len
< sizeof(struct ipv6hdr
)) {
248 net_notice_ratelimited("ipv6_conntrack_local: packet too short\n");
251 return __ipv6_conntrack_in(dev_net(out
), hooknum
, skb
, in
, out
, okfn
);
254 static struct nf_hook_ops ipv6_conntrack_ops
[] __read_mostly
= {
256 .hook
= ipv6_conntrack_in
,
257 .owner
= THIS_MODULE
,
259 .hooknum
= NF_INET_PRE_ROUTING
,
260 .priority
= NF_IP6_PRI_CONNTRACK
,
263 .hook
= ipv6_conntrack_local
,
264 .owner
= THIS_MODULE
,
266 .hooknum
= NF_INET_LOCAL_OUT
,
267 .priority
= NF_IP6_PRI_CONNTRACK
,
271 .owner
= THIS_MODULE
,
273 .hooknum
= NF_INET_POST_ROUTING
,
274 .priority
= NF_IP6_PRI_CONNTRACK_HELPER
,
277 .hook
= ipv6_confirm
,
278 .owner
= THIS_MODULE
,
280 .hooknum
= NF_INET_POST_ROUTING
,
281 .priority
= NF_IP6_PRI_LAST
,
285 .owner
= THIS_MODULE
,
287 .hooknum
= NF_INET_LOCAL_IN
,
288 .priority
= NF_IP6_PRI_CONNTRACK_HELPER
,
291 .hook
= ipv6_confirm
,
292 .owner
= THIS_MODULE
,
294 .hooknum
= NF_INET_LOCAL_IN
,
295 .priority
= NF_IP6_PRI_LAST
-1,
300 ipv6_getorigdst(struct sock
*sk
, int optval
, void __user
*user
, int *len
)
302 const struct inet_sock
*inet
= inet_sk(sk
);
303 const struct ipv6_pinfo
*inet6
= inet6_sk(sk
);
304 const struct nf_conntrack_tuple_hash
*h
;
305 struct sockaddr_in6 sin6
;
306 struct nf_conntrack_tuple tuple
= { .src
.l3num
= NFPROTO_IPV6
};
309 tuple
.src
.u3
.in6
= inet6
->rcv_saddr
;
310 tuple
.src
.u
.tcp
.port
= inet
->inet_sport
;
311 tuple
.dst
.u3
.in6
= inet6
->daddr
;
312 tuple
.dst
.u
.tcp
.port
= inet
->inet_dport
;
313 tuple
.dst
.protonum
= sk
->sk_protocol
;
315 if (sk
->sk_protocol
!= IPPROTO_TCP
&& sk
->sk_protocol
!= IPPROTO_SCTP
)
318 if (*len
< 0 || (unsigned int) *len
< sizeof(sin6
))
321 h
= nf_conntrack_find_get(sock_net(sk
), NF_CT_DEFAULT_ZONE
, &tuple
);
323 pr_debug("IP6T_SO_ORIGINAL_DST: Can't find %pI6c/%u-%pI6c/%u.\n",
324 &tuple
.src
.u3
.ip6
, ntohs(tuple
.src
.u
.tcp
.port
),
325 &tuple
.dst
.u3
.ip6
, ntohs(tuple
.dst
.u
.tcp
.port
));
329 ct
= nf_ct_tuplehash_to_ctrack(h
);
331 sin6
.sin6_family
= AF_INET6
;
332 sin6
.sin6_port
= ct
->tuplehash
[IP_CT_DIR_ORIGINAL
].tuple
.dst
.u
.tcp
.port
;
333 sin6
.sin6_flowinfo
= inet6
->flow_label
& IPV6_FLOWINFO_MASK
;
334 memcpy(&sin6
.sin6_addr
,
335 &ct
->tuplehash
[IP_CT_DIR_ORIGINAL
].tuple
.dst
.u3
.in6
,
336 sizeof(sin6
.sin6_addr
));
340 if (ipv6_addr_type(&sin6
.sin6_addr
) & IPV6_ADDR_LINKLOCAL
)
341 sin6
.sin6_scope_id
= sk
->sk_bound_dev_if
;
343 sin6
.sin6_scope_id
= 0;
345 return copy_to_user(user
, &sin6
, sizeof(sin6
)) ? -EFAULT
: 0;
348 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
350 #include <linux/netfilter/nfnetlink.h>
351 #include <linux/netfilter/nfnetlink_conntrack.h>
353 static int ipv6_tuple_to_nlattr(struct sk_buff
*skb
,
354 const struct nf_conntrack_tuple
*tuple
)
356 if (nla_put(skb
, CTA_IP_V6_SRC
, sizeof(u_int32_t
) * 4,
357 &tuple
->src
.u3
.ip6
) ||
358 nla_put(skb
, CTA_IP_V6_DST
, sizeof(u_int32_t
) * 4,
360 goto nla_put_failure
;
367 static const struct nla_policy ipv6_nla_policy
[CTA_IP_MAX
+1] = {
368 [CTA_IP_V6_SRC
] = { .len
= sizeof(u_int32_t
)*4 },
369 [CTA_IP_V6_DST
] = { .len
= sizeof(u_int32_t
)*4 },
372 static int ipv6_nlattr_to_tuple(struct nlattr
*tb
[],
373 struct nf_conntrack_tuple
*t
)
375 if (!tb
[CTA_IP_V6_SRC
] || !tb
[CTA_IP_V6_DST
])
378 memcpy(&t
->src
.u3
.ip6
, nla_data(tb
[CTA_IP_V6_SRC
]),
379 sizeof(u_int32_t
) * 4);
380 memcpy(&t
->dst
.u3
.ip6
, nla_data(tb
[CTA_IP_V6_DST
]),
381 sizeof(u_int32_t
) * 4);
386 static int ipv6_nlattr_tuple_size(void)
388 return nla_policy_len(ipv6_nla_policy
, CTA_IP_MAX
+ 1);
392 struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 __read_mostly
= {
395 .pkt_to_tuple
= ipv6_pkt_to_tuple
,
396 .invert_tuple
= ipv6_invert_tuple
,
397 .print_tuple
= ipv6_print_tuple
,
398 .get_l4proto
= ipv6_get_l4proto
,
399 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
400 .tuple_to_nlattr
= ipv6_tuple_to_nlattr
,
401 .nlattr_tuple_size
= ipv6_nlattr_tuple_size
,
402 .nlattr_to_tuple
= ipv6_nlattr_to_tuple
,
403 .nla_policy
= ipv6_nla_policy
,
408 MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6
));
409 MODULE_LICENSE("GPL");
410 MODULE_AUTHOR("Yasuyuki KOZAKAI @USAGI <yasuyuki.kozakai@toshiba.co.jp>");
412 static struct nf_sockopt_ops so_getorigdst6
= {
414 .get_optmin
= IP6T_SO_ORIGINAL_DST
,
415 .get_optmax
= IP6T_SO_ORIGINAL_DST
+ 1,
416 .get
= ipv6_getorigdst
,
417 .owner
= THIS_MODULE
,
420 static int ipv6_net_init(struct net
*net
)
424 ret
= nf_conntrack_l4proto_register(net
,
425 &nf_conntrack_l4proto_tcp6
);
427 printk(KERN_ERR
"nf_conntrack_l4proto_tcp6: protocol register failed\n");
430 ret
= nf_conntrack_l4proto_register(net
,
431 &nf_conntrack_l4proto_udp6
);
433 printk(KERN_ERR
"nf_conntrack_l4proto_udp6: protocol register failed\n");
436 ret
= nf_conntrack_l4proto_register(net
,
437 &nf_conntrack_l4proto_icmpv6
);
439 printk(KERN_ERR
"nf_conntrack_l4proto_icmp6: protocol register failed\n");
442 ret
= nf_conntrack_l3proto_register(net
,
443 &nf_conntrack_l3proto_ipv6
);
445 printk(KERN_ERR
"nf_conntrack_l3proto_ipv6: protocol register failed\n");
450 nf_conntrack_l4proto_unregister(net
,
451 &nf_conntrack_l4proto_icmpv6
);
453 nf_conntrack_l4proto_unregister(net
,
454 &nf_conntrack_l4proto_udp6
);
456 nf_conntrack_l4proto_unregister(net
,
457 &nf_conntrack_l4proto_tcp6
);
462 static void ipv6_net_exit(struct net
*net
)
464 nf_conntrack_l3proto_unregister(net
,
465 &nf_conntrack_l3proto_ipv6
);
466 nf_conntrack_l4proto_unregister(net
,
467 &nf_conntrack_l4proto_icmpv6
);
468 nf_conntrack_l4proto_unregister(net
,
469 &nf_conntrack_l4proto_udp6
);
470 nf_conntrack_l4proto_unregister(net
,
471 &nf_conntrack_l4proto_tcp6
);
474 static struct pernet_operations ipv6_net_ops
= {
475 .init
= ipv6_net_init
,
476 .exit
= ipv6_net_exit
,
479 static int __init
nf_conntrack_l3proto_ipv6_init(void)
484 nf_defrag_ipv6_enable();
486 ret
= nf_register_sockopt(&so_getorigdst6
);
488 pr_err("Unable to register netfilter socket option\n");
492 ret
= register_pernet_subsys(&ipv6_net_ops
);
495 ret
= nf_register_hooks(ipv6_conntrack_ops
,
496 ARRAY_SIZE(ipv6_conntrack_ops
));
498 pr_err("nf_conntrack_ipv6: can't register pre-routing defrag "
505 unregister_pernet_subsys(&ipv6_net_ops
);
507 nf_unregister_sockopt(&so_getorigdst6
);
511 static void __exit
nf_conntrack_l3proto_ipv6_fini(void)
514 nf_unregister_hooks(ipv6_conntrack_ops
, ARRAY_SIZE(ipv6_conntrack_ops
));
515 unregister_pernet_subsys(&ipv6_net_ops
);
516 nf_unregister_sockopt(&so_getorigdst6
);
519 module_init(nf_conntrack_l3proto_ipv6_init
);
520 module_exit(nf_conntrack_l3proto_ipv6_fini
);