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/nf_conntrack_seqadj.h>
32 #include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
33 #include <net/netfilter/nf_nat_helper.h>
34 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
35 #include <net/netfilter/nf_log.h>
37 static bool ipv6_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff,
38 struct nf_conntrack_tuple *tuple)
43 ap = skb_header_pointer(skb, nhoff + offsetof(struct ipv6hdr, saddr),
44 sizeof(_addrs), _addrs);
48 memcpy(tuple->src.u3.ip6, ap, sizeof(tuple->src.u3.ip6));
49 memcpy(tuple->dst.u3.ip6, ap + 4, sizeof(tuple->dst.u3.ip6));
54 static bool ipv6_invert_tuple(struct nf_conntrack_tuple *tuple,
55 const struct nf_conntrack_tuple *orig)
57 memcpy(tuple->src.u3.ip6, orig->dst.u3.ip6, sizeof(tuple->src.u3.ip6));
58 memcpy(tuple->dst.u3.ip6, orig->src.u3.ip6, sizeof(tuple->dst.u3.ip6));
63 static int ipv6_print_tuple(struct seq_file *s,
64 const struct nf_conntrack_tuple *tuple)
66 return seq_printf(s, "src=%pI6 dst=%pI6 ",
67 tuple->src.u3.ip6, tuple->dst.u3.ip6);
70 static int ipv6_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
71 unsigned int *dataoff, u_int8_t *protonum)
73 unsigned int extoff = nhoff + sizeof(struct ipv6hdr);
78 if (skb_copy_bits(skb, nhoff + offsetof(struct ipv6hdr, nexthdr),
79 &nexthdr, sizeof(nexthdr)) != 0) {
80 pr_debug("ip6_conntrack_core: can't get nexthdr\n");
83 protoff = ipv6_skip_exthdr(skb, extoff, &nexthdr, &frag_off);
85 * (protoff == skb->len) means the packet has not data, just
86 * IPv6 and possibly extensions headers, but it is tracked anyway
88 if (protoff < 0 || (frag_off & htons(~0x7)) != 0) {
89 pr_debug("ip6_conntrack_core: can't find proto in pkt\n");
98 static unsigned int ipv6_helper(const struct nf_hook_ops *ops,
100 const struct net_device *in,
101 const struct net_device *out,
102 int (*okfn)(struct sk_buff *))
105 const struct nf_conn_help *help;
106 const struct nf_conntrack_helper *helper;
107 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 return helper->help(skb, protoff, ct, ctinfo);
136 static unsigned int ipv6_confirm(const struct nf_hook_ops *ops,
138 const struct net_device *in,
139 const struct net_device *out,
140 int (*okfn)(struct sk_buff *))
143 enum ip_conntrack_info ctinfo;
144 unsigned char pnum = ipv6_hdr(skb)->nexthdr;
148 ct = nf_ct_get(skb, &ctinfo);
149 if (!ct || ctinfo == IP_CT_RELATED_REPLY)
152 protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &pnum,
154 if (protoff < 0 || (frag_off & htons(~0x7)) != 0) {
155 pr_debug("proto header not found\n");
159 /* adjust seqs for loopback traffic only in outgoing direction */
160 if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
161 !nf_is_loopback_packet(skb)) {
162 if (!nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) {
163 NF_CT_STAT_INC_ATOMIC(nf_ct_net(ct), drop);
168 /* We've seen it coming out the other side: confirm it */
169 return nf_conntrack_confirm(skb);
172 static unsigned int ipv6_conntrack_in(const struct nf_hook_ops *ops,
174 const struct net_device *in,
175 const struct net_device *out,
176 int (*okfn)(struct sk_buff *))
178 return nf_conntrack_in(dev_net(in), PF_INET6, ops->hooknum, skb);
181 static unsigned int ipv6_conntrack_local(const struct nf_hook_ops *ops,
183 const struct net_device *in,
184 const struct net_device *out,
185 int (*okfn)(struct sk_buff *))
187 /* root is playing with raw sockets. */
188 if (skb->len < sizeof(struct ipv6hdr)) {
189 net_notice_ratelimited("ipv6_conntrack_local: packet too short\n");
192 return nf_conntrack_in(dev_net(out), PF_INET6, ops->hooknum, skb);
195 static struct nf_hook_ops ipv6_conntrack_ops[] __read_mostly = {
197 .hook = ipv6_conntrack_in,
198 .owner = THIS_MODULE,
200 .hooknum = NF_INET_PRE_ROUTING,
201 .priority = NF_IP6_PRI_CONNTRACK,
204 .hook = ipv6_conntrack_local,
205 .owner = THIS_MODULE,
207 .hooknum = NF_INET_LOCAL_OUT,
208 .priority = NF_IP6_PRI_CONNTRACK,
212 .owner = THIS_MODULE,
214 .hooknum = NF_INET_POST_ROUTING,
215 .priority = NF_IP6_PRI_CONNTRACK_HELPER,
218 .hook = ipv6_confirm,
219 .owner = THIS_MODULE,
221 .hooknum = NF_INET_POST_ROUTING,
222 .priority = NF_IP6_PRI_LAST,
226 .owner = THIS_MODULE,
228 .hooknum = NF_INET_LOCAL_IN,
229 .priority = NF_IP6_PRI_CONNTRACK_HELPER,
232 .hook = ipv6_confirm,
233 .owner = THIS_MODULE,
235 .hooknum = NF_INET_LOCAL_IN,
236 .priority = NF_IP6_PRI_LAST-1,
241 ipv6_getorigdst(struct sock *sk, int optval, void __user *user, int *len)
243 const struct inet_sock *inet = inet_sk(sk);
244 const struct ipv6_pinfo *inet6 = inet6_sk(sk);
245 const struct nf_conntrack_tuple_hash *h;
246 struct sockaddr_in6 sin6;
247 struct nf_conntrack_tuple tuple = { .src.l3num = NFPROTO_IPV6 };
250 tuple.src.u3.in6 = sk->sk_v6_rcv_saddr;
251 tuple.src.u.tcp.port = inet->inet_sport;
252 tuple.dst.u3.in6 = sk->sk_v6_daddr;
253 tuple.dst.u.tcp.port = inet->inet_dport;
254 tuple.dst.protonum = sk->sk_protocol;
256 if (sk->sk_protocol != IPPROTO_TCP && sk->sk_protocol != IPPROTO_SCTP)
259 if (*len < 0 || (unsigned int) *len < sizeof(sin6))
262 h = nf_conntrack_find_get(sock_net(sk), NF_CT_DEFAULT_ZONE, &tuple);
264 pr_debug("IP6T_SO_ORIGINAL_DST: Can't find %pI6c/%u-%pI6c/%u.\n",
265 &tuple.src.u3.ip6, ntohs(tuple.src.u.tcp.port),
266 &tuple.dst.u3.ip6, ntohs(tuple.dst.u.tcp.port));
270 ct = nf_ct_tuplehash_to_ctrack(h);
272 sin6.sin6_family = AF_INET6;
273 sin6.sin6_port = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u.tcp.port;
274 sin6.sin6_flowinfo = inet6->flow_label & IPV6_FLOWINFO_MASK;
275 memcpy(&sin6.sin6_addr,
276 &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u3.in6,
277 sizeof(sin6.sin6_addr));
280 sin6.sin6_scope_id = ipv6_iface_scope_id(&sin6.sin6_addr,
281 sk->sk_bound_dev_if);
282 return copy_to_user(user, &sin6, sizeof(sin6)) ? -EFAULT : 0;
285 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
287 #include <linux/netfilter/nfnetlink.h>
288 #include <linux/netfilter/nfnetlink_conntrack.h>
290 static int ipv6_tuple_to_nlattr(struct sk_buff *skb,
291 const struct nf_conntrack_tuple *tuple)
293 if (nla_put(skb, CTA_IP_V6_SRC, sizeof(u_int32_t) * 4,
294 &tuple->src.u3.ip6) ||
295 nla_put(skb, CTA_IP_V6_DST, sizeof(u_int32_t) * 4,
297 goto nla_put_failure;
304 static const struct nla_policy ipv6_nla_policy[CTA_IP_MAX+1] = {
305 [CTA_IP_V6_SRC] = { .len = sizeof(u_int32_t)*4 },
306 [CTA_IP_V6_DST] = { .len = sizeof(u_int32_t)*4 },
309 static int ipv6_nlattr_to_tuple(struct nlattr *tb[],
310 struct nf_conntrack_tuple *t)
312 if (!tb[CTA_IP_V6_SRC] || !tb[CTA_IP_V6_DST])
315 memcpy(&t->src.u3.ip6, nla_data(tb[CTA_IP_V6_SRC]),
316 sizeof(u_int32_t) * 4);
317 memcpy(&t->dst.u3.ip6, nla_data(tb[CTA_IP_V6_DST]),
318 sizeof(u_int32_t) * 4);
323 static int ipv6_nlattr_tuple_size(void)
325 return nla_policy_len(ipv6_nla_policy, CTA_IP_MAX + 1);
329 struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 __read_mostly = {
332 .pkt_to_tuple = ipv6_pkt_to_tuple,
333 .invert_tuple = ipv6_invert_tuple,
334 .print_tuple = ipv6_print_tuple,
335 .get_l4proto = ipv6_get_l4proto,
336 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
337 .tuple_to_nlattr = ipv6_tuple_to_nlattr,
338 .nlattr_tuple_size = ipv6_nlattr_tuple_size,
339 .nlattr_to_tuple = ipv6_nlattr_to_tuple,
340 .nla_policy = ipv6_nla_policy,
345 MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6));
346 MODULE_LICENSE("GPL");
347 MODULE_AUTHOR("Yasuyuki KOZAKAI @USAGI <yasuyuki.kozakai@toshiba.co.jp>");
349 static struct nf_sockopt_ops so_getorigdst6 = {
351 .get_optmin = IP6T_SO_ORIGINAL_DST,
352 .get_optmax = IP6T_SO_ORIGINAL_DST + 1,
353 .get = ipv6_getorigdst,
354 .owner = THIS_MODULE,
357 static int ipv6_net_init(struct net *net)
361 ret = nf_ct_l4proto_pernet_register(net, &nf_conntrack_l4proto_tcp6);
363 pr_err("nf_conntrack_tcp6: pernet registration failed\n");
366 ret = nf_ct_l4proto_pernet_register(net, &nf_conntrack_l4proto_udp6);
368 pr_err("nf_conntrack_udp6: pernet registration failed\n");
371 ret = nf_ct_l4proto_pernet_register(net, &nf_conntrack_l4proto_icmpv6);
373 pr_err("nf_conntrack_icmp6: pernet registration failed\n");
376 ret = nf_ct_l3proto_pernet_register(net, &nf_conntrack_l3proto_ipv6);
378 pr_err("nf_conntrack_ipv6: pernet registration failed.\n");
383 nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_icmpv6);
385 nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_udp6);
387 nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_tcp6);
392 static void ipv6_net_exit(struct net *net)
394 nf_ct_l3proto_pernet_unregister(net, &nf_conntrack_l3proto_ipv6);
395 nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_icmpv6);
396 nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_udp6);
397 nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_tcp6);
400 static struct pernet_operations ipv6_net_ops = {
401 .init = ipv6_net_init,
402 .exit = ipv6_net_exit,
405 static int __init nf_conntrack_l3proto_ipv6_init(void)
410 nf_defrag_ipv6_enable();
412 ret = nf_register_sockopt(&so_getorigdst6);
414 pr_err("Unable to register netfilter socket option\n");
418 ret = register_pernet_subsys(&ipv6_net_ops);
420 goto cleanup_sockopt;
422 ret = nf_register_hooks(ipv6_conntrack_ops,
423 ARRAY_SIZE(ipv6_conntrack_ops));
425 pr_err("nf_conntrack_ipv6: can't register pre-routing defrag "
430 ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_tcp6);
432 pr_err("nf_conntrack_ipv6: can't register tcp6 proto.\n");
436 ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_udp6);
438 pr_err("nf_conntrack_ipv6: can't register udp6 proto.\n");
442 ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_icmpv6);
444 pr_err("nf_conntrack_ipv6: can't register icmpv6 proto.\n");
448 ret = nf_ct_l3proto_register(&nf_conntrack_l3proto_ipv6);
450 pr_err("nf_conntrack_ipv6: can't register ipv6 proto.\n");
456 nf_ct_l4proto_unregister(&nf_conntrack_l4proto_icmpv6);
458 nf_ct_l4proto_unregister(&nf_conntrack_l4proto_udp6);
460 nf_ct_l4proto_unregister(&nf_conntrack_l4proto_tcp6);
462 nf_unregister_hooks(ipv6_conntrack_ops, ARRAY_SIZE(ipv6_conntrack_ops));
464 unregister_pernet_subsys(&ipv6_net_ops);
466 nf_unregister_sockopt(&so_getorigdst6);
470 static void __exit nf_conntrack_l3proto_ipv6_fini(void)
473 nf_ct_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
474 nf_ct_l4proto_unregister(&nf_conntrack_l4proto_tcp6);
475 nf_ct_l4proto_unregister(&nf_conntrack_l4proto_udp6);
476 nf_ct_l4proto_unregister(&nf_conntrack_l4proto_icmpv6);
477 nf_unregister_hooks(ipv6_conntrack_ops, ARRAY_SIZE(ipv6_conntrack_ops));
478 unregister_pernet_subsys(&ipv6_net_ops);
479 nf_unregister_sockopt(&so_getorigdst6);
482 module_init(nf_conntrack_l3proto_ipv6_init);
483 module_exit(nf_conntrack_l3proto_ipv6_fini);