?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Replace <asm/uaccess.h> with <linux/uaccess.h> globally
[linux-2.6/btrfs-unstable.git] / net / ipv6 / netfilter / nf_conntrack_l3proto_ipv6.c
blob4e34024868334427194992d8033d0d58a0361d3b
1 /*
2 * Copyright (C)2004 USAGI/WIDE Project
3 *
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.
7 *
8 * Author:
9 * Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
10 */
11
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 <net/ipv6.h>
20 #include <net/inet_frag.h>
21
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>
36
37 static int conntrack6_net_id;
38 static DEFINE_MUTEX(register_ipv6_hooks);
39
40 struct conntrack6_net {
41 unsigned int users;
42 };
43
44 static bool ipv6_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff,
45 struct nf_conntrack_tuple *tuple)
46 {
47 const u_int32_t *ap;
48 u_int32_t _addrs[8];
49
50 ap = skb_header_pointer(skb, nhoff + offsetof(struct ipv6hdr, saddr),
51 sizeof(_addrs), _addrs);
52 if (ap == NULL)
53 return false;
54
55 memcpy(tuple->src.u3.ip6, ap, sizeof(tuple->src.u3.ip6));
56 memcpy(tuple->dst.u3.ip6, ap + 4, sizeof(tuple->dst.u3.ip6));
57
58 return true;
59 }
60
61 static bool ipv6_invert_tuple(struct nf_conntrack_tuple *tuple,
62 const struct nf_conntrack_tuple *orig)
63 {
64 memcpy(tuple->src.u3.ip6, orig->dst.u3.ip6, sizeof(tuple->src.u3.ip6));
65 memcpy(tuple->dst.u3.ip6, orig->src.u3.ip6, sizeof(tuple->dst.u3.ip6));
66
67 return true;
68 }
69
70 static void ipv6_print_tuple(struct seq_file *s,
71 const struct nf_conntrack_tuple *tuple)
72 {
73 seq_printf(s, "src=%pI6 dst=%pI6 ",
74 tuple->src.u3.ip6, tuple->dst.u3.ip6);
75 }
76
77 static int ipv6_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
78 unsigned int *dataoff, u_int8_t *protonum)
79 {
80 unsigned int extoff = nhoff + sizeof(struct ipv6hdr);
81 __be16 frag_off;
82 int protoff;
83 u8 nexthdr;
84
85 if (skb_copy_bits(skb, nhoff + offsetof(struct ipv6hdr, nexthdr),
86 &nexthdr, sizeof(nexthdr)) != 0) {
87 pr_debug("ip6_conntrack_core: can't get nexthdr\n");
88 return -NF_ACCEPT;
89 }
90 protoff = ipv6_skip_exthdr(skb, extoff, &nexthdr, &frag_off);
91 /*
92 * (protoff == skb->len) means the packet has not data, just
93 * IPv6 and possibly extensions headers, but it is tracked anyway
94 */
95 if (protoff < 0 || (frag_off & htons(~0x7)) != 0) {
96 pr_debug("ip6_conntrack_core: can't find proto in pkt\n");
97 return -NF_ACCEPT;
98 }
99
100 *dataoff = protoff;
101 *protonum = nexthdr;
102 return NF_ACCEPT;
103 }
104
105 static unsigned int ipv6_helper(void *priv,
106 struct sk_buff *skb,
107 const struct nf_hook_state *state)
108 {
109 struct nf_conn *ct;
110 const struct nf_conn_help *help;
111 const struct nf_conntrack_helper *helper;
112 enum ip_conntrack_info ctinfo;
113 __be16 frag_off;
114 int protoff;
115 u8 nexthdr;
116
117 /* This is where we call the helper: as the packet goes out. */
118 ct = nf_ct_get(skb, &ctinfo);
119 if (!ct || ctinfo == IP_CT_RELATED_REPLY)
120 return NF_ACCEPT;
121
122 help = nfct_help(ct);
123 if (!help)
124 return NF_ACCEPT;
125 /* rcu_read_lock()ed by nf_hook_thresh */
126 helper = rcu_dereference(help->helper);
127 if (!helper)
128 return NF_ACCEPT;
129
130 nexthdr = ipv6_hdr(skb)->nexthdr;
131 protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr,
132 &frag_off);
133 if (protoff < 0 || (frag_off & htons(~0x7)) != 0) {
134 pr_debug("proto header not found\n");
135 return NF_ACCEPT;
136 }
137
138 return helper->help(skb, protoff, ct, ctinfo);
139 }
140
141 static unsigned int ipv6_confirm(void *priv,
142 struct sk_buff *skb,
143 const struct nf_hook_state *state)
144 {
145 struct nf_conn *ct;
146 enum ip_conntrack_info ctinfo;
147 unsigned char pnum = ipv6_hdr(skb)->nexthdr;
148 int protoff;
149 __be16 frag_off;
150
151 ct = nf_ct_get(skb, &ctinfo);
152 if (!ct || ctinfo == IP_CT_RELATED_REPLY)
153 goto out;
154
155 protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &pnum,
156 &frag_off);
157 if (protoff < 0 || (frag_off & htons(~0x7)) != 0) {
158 pr_debug("proto header not found\n");
159 goto out;
160 }
161
162 /* adjust seqs for loopback traffic only in outgoing direction */
163 if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
164 !nf_is_loopback_packet(skb)) {
165 if (!nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) {
166 NF_CT_STAT_INC_ATOMIC(nf_ct_net(ct), drop);
167 return NF_DROP;
168 }
169 }
170 out:
171 /* We've seen it coming out the other side: confirm it */
172 return nf_conntrack_confirm(skb);
173 }
174
175 static unsigned int ipv6_conntrack_in(void *priv,
176 struct sk_buff *skb,
177 const struct nf_hook_state *state)
178 {
179 return nf_conntrack_in(state->net, PF_INET6, state->hook, skb);
180 }
181
182 static unsigned int ipv6_conntrack_local(void *priv,
183 struct sk_buff *skb,
184 const struct nf_hook_state *state)
185 {
186 /* root is playing with raw sockets. */
187 if (skb->len < sizeof(struct ipv6hdr)) {
188 net_notice_ratelimited("ipv6_conntrack_local: packet too short\n");
189 return NF_ACCEPT;
190 }
191 return nf_conntrack_in(state->net, PF_INET6, state->hook, skb);
192 }
193
194 static struct nf_hook_ops ipv6_conntrack_ops[] __read_mostly = {
195 {
196 .hook = ipv6_conntrack_in,
197 .pf = NFPROTO_IPV6,
198 .hooknum = NF_INET_PRE_ROUTING,
199 .priority = NF_IP6_PRI_CONNTRACK,
200 },
201 {
202 .hook = ipv6_conntrack_local,
203 .pf = NFPROTO_IPV6,
204 .hooknum = NF_INET_LOCAL_OUT,
205 .priority = NF_IP6_PRI_CONNTRACK,
206 },
207 {
208 .hook = ipv6_helper,
209 .pf = NFPROTO_IPV6,
210 .hooknum = NF_INET_POST_ROUTING,
211 .priority = NF_IP6_PRI_CONNTRACK_HELPER,
212 },
213 {
214 .hook = ipv6_confirm,
215 .pf = NFPROTO_IPV6,
216 .hooknum = NF_INET_POST_ROUTING,
217 .priority = NF_IP6_PRI_LAST,
218 },
219 {
220 .hook = ipv6_helper,
221 .pf = NFPROTO_IPV6,
222 .hooknum = NF_INET_LOCAL_IN,
223 .priority = NF_IP6_PRI_CONNTRACK_HELPER,
224 },
225 {
226 .hook = ipv6_confirm,
227 .pf = NFPROTO_IPV6,
228 .hooknum = NF_INET_LOCAL_IN,
229 .priority = NF_IP6_PRI_LAST-1,
230 },
231 };
232
233 static int
234 ipv6_getorigdst(struct sock *sk, int optval, void __user *user, int *len)
235 {
236 const struct inet_sock *inet = inet_sk(sk);
237 const struct ipv6_pinfo *inet6 = inet6_sk(sk);
238 const struct nf_conntrack_tuple_hash *h;
239 struct sockaddr_in6 sin6;
240 struct nf_conntrack_tuple tuple = { .src.l3num = NFPROTO_IPV6 };
241 struct nf_conn *ct;
242
243 tuple.src.u3.in6 = sk->sk_v6_rcv_saddr;
244 tuple.src.u.tcp.port = inet->inet_sport;
245 tuple.dst.u3.in6 = sk->sk_v6_daddr;
246 tuple.dst.u.tcp.port = inet->inet_dport;
247 tuple.dst.protonum = sk->sk_protocol;
248
249 if (sk->sk_protocol != IPPROTO_TCP && sk->sk_protocol != IPPROTO_SCTP)
250 return -ENOPROTOOPT;
251
252 if (*len < 0 || (unsigned int) *len < sizeof(sin6))
253 return -EINVAL;
254
255 h = nf_conntrack_find_get(sock_net(sk), &nf_ct_zone_dflt, &tuple);
256 if (!h) {
257 pr_debug("IP6T_SO_ORIGINAL_DST: Can't find %pI6c/%u-%pI6c/%u.\n",
258 &tuple.src.u3.ip6, ntohs(tuple.src.u.tcp.port),
259 &tuple.dst.u3.ip6, ntohs(tuple.dst.u.tcp.port));
260 return -ENOENT;
261 }
262
263 ct = nf_ct_tuplehash_to_ctrack(h);
264
265 sin6.sin6_family = AF_INET6;
266 sin6.sin6_port = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u.tcp.port;
267 sin6.sin6_flowinfo = inet6->flow_label & IPV6_FLOWINFO_MASK;
268 memcpy(&sin6.sin6_addr,
269 &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u3.in6,
270 sizeof(sin6.sin6_addr));
271
272 nf_ct_put(ct);
273 sin6.sin6_scope_id = ipv6_iface_scope_id(&sin6.sin6_addr,
274 sk->sk_bound_dev_if);
275 return copy_to_user(user, &sin6, sizeof(sin6)) ? -EFAULT : 0;
276 }
277
278 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
279
280 #include <linux/netfilter/nfnetlink.h>
281 #include <linux/netfilter/nfnetlink_conntrack.h>
282
283 static int ipv6_tuple_to_nlattr(struct sk_buff *skb,
284 const struct nf_conntrack_tuple *tuple)
285 {
286 if (nla_put_in6_addr(skb, CTA_IP_V6_SRC, &tuple->src.u3.in6) ||
287 nla_put_in6_addr(skb, CTA_IP_V6_DST, &tuple->dst.u3.in6))
288 goto nla_put_failure;
289 return 0;
290
291 nla_put_failure:
292 return -1;
293 }
294
295 static const struct nla_policy ipv6_nla_policy[CTA_IP_MAX+1] = {
296 [CTA_IP_V6_SRC] = { .len = sizeof(u_int32_t)*4 },
297 [CTA_IP_V6_DST] = { .len = sizeof(u_int32_t)*4 },
298 };
299
300 static int ipv6_nlattr_to_tuple(struct nlattr *tb[],
301 struct nf_conntrack_tuple *t)
302 {
303 if (!tb[CTA_IP_V6_SRC] || !tb[CTA_IP_V6_DST])
304 return -EINVAL;
305
306 t->src.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_SRC]);
307 t->dst.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_DST]);
308
309 return 0;
310 }
311
312 static int ipv6_nlattr_tuple_size(void)
313 {
314 return nla_policy_len(ipv6_nla_policy, CTA_IP_MAX + 1);
315 }
316 #endif
317
318 static int ipv6_hooks_register(struct net *net)
319 {
320 struct conntrack6_net *cnet = net_generic(net, conntrack6_net_id);
321 int err = 0;
322
323 mutex_lock(&register_ipv6_hooks);
324 cnet->users++;
325 if (cnet->users > 1)
326 goto out_unlock;
327
328 err = nf_defrag_ipv6_enable(net);
329 if (err < 0) {
330 cnet->users = 0;
331 goto out_unlock;
332 }
333
334 err = nf_register_net_hooks(net, ipv6_conntrack_ops,
335 ARRAY_SIZE(ipv6_conntrack_ops));
336 if (err)
337 cnet->users = 0;
338 out_unlock:
339 mutex_unlock(&register_ipv6_hooks);
340 return err;
341 }
342
343 static void ipv6_hooks_unregister(struct net *net)
344 {
345 struct conntrack6_net *cnet = net_generic(net, conntrack6_net_id);
346
347 mutex_lock(&register_ipv6_hooks);
348 if (cnet->users && (--cnet->users == 0))
349 nf_unregister_net_hooks(net, ipv6_conntrack_ops,
350 ARRAY_SIZE(ipv6_conntrack_ops));
351 mutex_unlock(&register_ipv6_hooks);
352 }
353
354 struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 __read_mostly = {
355 .l3proto = PF_INET6,
356 .name = "ipv6",
357 .pkt_to_tuple = ipv6_pkt_to_tuple,
358 .invert_tuple = ipv6_invert_tuple,
359 .print_tuple = ipv6_print_tuple,
360 .get_l4proto = ipv6_get_l4proto,
361 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
362 .tuple_to_nlattr = ipv6_tuple_to_nlattr,
363 .nlattr_tuple_size = ipv6_nlattr_tuple_size,
364 .nlattr_to_tuple = ipv6_nlattr_to_tuple,
365 .nla_policy = ipv6_nla_policy,
366 #endif
367 .net_ns_get = ipv6_hooks_register,
368 .net_ns_put = ipv6_hooks_unregister,
369 .me = THIS_MODULE,
370 };
371
372 MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6));
373 MODULE_LICENSE("GPL");
374 MODULE_AUTHOR("Yasuyuki KOZAKAI @USAGI <yasuyuki.kozakai@toshiba.co.jp>");
375
376 static struct nf_sockopt_ops so_getorigdst6 = {
377 .pf = NFPROTO_IPV6,
378 .get_optmin = IP6T_SO_ORIGINAL_DST,
379 .get_optmax = IP6T_SO_ORIGINAL_DST + 1,
380 .get = ipv6_getorigdst,
381 .owner = THIS_MODULE,
382 };
383
384 static struct nf_conntrack_l4proto *builtin_l4proto6[] = {
385 &nf_conntrack_l4proto_tcp6,
386 &nf_conntrack_l4proto_udp6,
387 &nf_conntrack_l4proto_icmpv6,
388 #ifdef CONFIG_NF_CT_PROTO_DCCP
389 &nf_conntrack_l4proto_dccp6,
390 #endif
391 #ifdef CONFIG_NF_CT_PROTO_SCTP
392 &nf_conntrack_l4proto_sctp6,
393 #endif
394 #ifdef CONFIG_NF_CT_PROTO_UDPLITE
395 &nf_conntrack_l4proto_udplite6,
396 #endif
397 };
398
399 static int ipv6_net_init(struct net *net)
400 {
401 int ret = 0;
402
403 ret = nf_ct_l4proto_pernet_register(net, builtin_l4proto6,
404 ARRAY_SIZE(builtin_l4proto6));
405 if (ret < 0)
406 return ret;
407
408 ret = nf_ct_l3proto_pernet_register(net, &nf_conntrack_l3proto_ipv6);
409 if (ret < 0) {
410 pr_err("nf_conntrack_ipv6: pernet registration failed.\n");
411 nf_ct_l4proto_pernet_unregister(net, builtin_l4proto6,
412 ARRAY_SIZE(builtin_l4proto6));
413 }
414 return ret;
415 }
416
417 static void ipv6_net_exit(struct net *net)
418 {
419 nf_ct_l3proto_pernet_unregister(net, &nf_conntrack_l3proto_ipv6);
420 nf_ct_l4proto_pernet_unregister(net, builtin_l4proto6,
421 ARRAY_SIZE(builtin_l4proto6));
422 }
423
424 static struct pernet_operations ipv6_net_ops = {
425 .init = ipv6_net_init,
426 .exit = ipv6_net_exit,
427 .id = &conntrack6_net_id,
428 .size = sizeof(struct conntrack6_net),
429 };
430
431 static int __init nf_conntrack_l3proto_ipv6_init(void)
432 {
433 int ret = 0;
434
435 need_conntrack();
436
437 ret = nf_register_sockopt(&so_getorigdst6);
438 if (ret < 0) {
439 pr_err("Unable to register netfilter socket option\n");
440 return ret;
441 }
442
443 ret = register_pernet_subsys(&ipv6_net_ops);
444 if (ret < 0)
445 goto cleanup_sockopt;
446
447 ret = nf_ct_l4proto_register(builtin_l4proto6,
448 ARRAY_SIZE(builtin_l4proto6));
449 if (ret < 0)
450 goto cleanup_pernet;
451
452 ret = nf_ct_l3proto_register(&nf_conntrack_l3proto_ipv6);
453 if (ret < 0) {
454 pr_err("nf_conntrack_ipv6: can't register ipv6 proto.\n");
455 goto cleanup_l4proto;
456 }
457 return ret;
458 cleanup_l4proto:
459 nf_ct_l4proto_unregister(builtin_l4proto6,
460 ARRAY_SIZE(builtin_l4proto6));
461 cleanup_pernet:
462 unregister_pernet_subsys(&ipv6_net_ops);
463 cleanup_sockopt:
464 nf_unregister_sockopt(&so_getorigdst6);
465 return ret;
466 }
467
468 static void __exit nf_conntrack_l3proto_ipv6_fini(void)
469 {
470 synchronize_net();
471 nf_ct_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
472 nf_ct_l4proto_unregister(builtin_l4proto6,
473 ARRAY_SIZE(builtin_l4proto6));
474 unregister_pernet_subsys(&ipv6_net_ops);
475 nf_unregister_sockopt(&so_getorigdst6);
476 }
477
478 module_init(nf_conntrack_l3proto_ipv6_init);
479 module_exit(nf_conntrack_l3proto_ipv6_fini);
(deprecated) Btrfs devel tree