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>
11 * 16 Dec 2003: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
12 * - support Layer 3 protocol independent connection tracking.
13 * Based on the original ip_conntrack code which had the following
14 * copyright information:
15 * (C) 1999-2001 Paul `Rusty' Russell
16 * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
18 * 23 Mar 2004: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
19 * - add get_features() to support various size of conntrack
23 #include <linux/config.h>
24 #include <linux/types.h>
25 #include <linux/ipv6.h>
26 #include <linux/in6.h>
27 #include <linux/netfilter.h>
28 #include <linux/module.h>
29 #include <linux/skbuff.h>
30 #include <linux/icmp.h>
31 #include <linux/sysctl.h>
34 #include <linux/netfilter_ipv6.h>
35 #include <net/netfilter/nf_conntrack.h>
36 #include <net/netfilter/nf_conntrack_helper.h>
37 #include <net/netfilter/nf_conntrack_protocol.h>
38 #include <net/netfilter/nf_conntrack_l3proto.h>
39 #include <net/netfilter/nf_conntrack_core.h>
44 #define DEBUGP(format, args...)
47 DECLARE_PER_CPU(struct ip_conntrack_stat, nf_conntrack_stat);
49 static int ipv6_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff,
50 struct nf_conntrack_tuple *tuple)
52 u_int32_t _addrs[8], *ap;
54 ap = skb_header_pointer(skb, nhoff + offsetof(struct ipv6hdr, saddr),
55 sizeof(_addrs), _addrs);
59 memcpy(tuple->src.u3.ip6, ap, sizeof(tuple->src.u3.ip6));
60 memcpy(tuple->dst.u3.ip6, ap + 4, sizeof(tuple->dst.u3.ip6));
65 static int ipv6_invert_tuple(struct nf_conntrack_tuple *tuple,
66 const struct nf_conntrack_tuple *orig)
68 memcpy(tuple->src.u3.ip6, orig->dst.u3.ip6, sizeof(tuple->src.u3.ip6));
69 memcpy(tuple->dst.u3.ip6, orig->src.u3.ip6, sizeof(tuple->dst.u3.ip6));
74 static int ipv6_print_tuple(struct seq_file *s,
75 const struct nf_conntrack_tuple *tuple)
77 return seq_printf(s, "src=" NIP6_FMT " dst=" NIP6_FMT " ",
78 NIP6(*((struct in6_addr *)tuple->src.u3.ip6)),
79 NIP6(*((struct in6_addr *)tuple->dst.u3.ip6)));
82 static int ipv6_print_conntrack(struct seq_file *s,
83 const struct nf_conn *conntrack)
89 * Based on ipv6_skip_exthdr() in net/ipv6/exthdr.c
91 * This function parses (probably truncated) exthdr set "hdr"
92 * of length "len". "nexthdrp" initially points to some place,
93 * where type of the first header can be found.
95 * It skips all well-known exthdrs, and returns pointer to the start
96 * of unparsable area i.e. the first header with unknown type.
97 * if success, *nexthdr is updated by type/protocol of this header.
99 * NOTES: - it may return pointer pointing beyond end of packet,
100 * if the last recognized header is truncated in the middle.
101 * - if packet is truncated, so that all parsed headers are skipped,
103 * - if packet is fragmented, return pointer of the fragment header.
104 * - ESP is unparsable for now and considered like
105 * normal payload protocol.
106 * - Note also special handling of AUTH header. Thanks to IPsec wizards.
109 int nf_ct_ipv6_skip_exthdr(struct sk_buff *skb, int start, u8 *nexthdrp,
112 u8 nexthdr = *nexthdrp;
114 while (ipv6_ext_hdr(nexthdr)) {
115 struct ipv6_opt_hdr hdr;
118 if (len < (int)sizeof(struct ipv6_opt_hdr))
120 if (nexthdr == NEXTHDR_NONE)
122 if (nexthdr == NEXTHDR_FRAGMENT)
124 if (skb_copy_bits(skb, start, &hdr, sizeof(hdr)))
126 if (nexthdr == NEXTHDR_AUTH)
127 hdrlen = (hdr.hdrlen+2)<<2;
129 hdrlen = ipv6_optlen(&hdr);
131 nexthdr = hdr.nexthdr;
141 ipv6_prepare(struct sk_buff **pskb, unsigned int hooknum, unsigned int *dataoff,
148 extoff = (u8*)((*pskb)->nh.ipv6h + 1) - (*pskb)->data;
149 pnum = (*pskb)->nh.ipv6h->nexthdr;
151 protoff = nf_ct_ipv6_skip_exthdr(*pskb, extoff, &pnum,
152 (*pskb)->len - extoff);
155 * (protoff == (*pskb)->len) mean that the packet doesn't have no data
156 * except of IPv6 & ext headers. but it's tracked anyway. - YK
158 if ((protoff < 0) || (protoff > (*pskb)->len)) {
159 DEBUGP("ip6_conntrack_core: can't find proto in pkt\n");
160 NF_CT_STAT_INC(error);
161 NF_CT_STAT_INC(invalid);
170 static u_int32_t ipv6_get_features(const struct nf_conntrack_tuple *tuple)
172 return NF_CT_F_BASIC;
175 static unsigned int ipv6_confirm(unsigned int hooknum,
176 struct sk_buff **pskb,
177 const struct net_device *in,
178 const struct net_device *out,
179 int (*okfn)(struct sk_buff *))
182 struct nf_conn_help *help;
183 enum ip_conntrack_info ctinfo;
184 unsigned int ret, protoff;
185 unsigned int extoff = (u8*)((*pskb)->nh.ipv6h + 1)
187 unsigned char pnum = (*pskb)->nh.ipv6h->nexthdr;
190 /* This is where we call the helper: as the packet goes out. */
191 ct = nf_ct_get(*pskb, &ctinfo);
195 help = nfct_help(ct);
196 if (!help || !help->helper)
199 protoff = nf_ct_ipv6_skip_exthdr(*pskb, extoff, &pnum,
200 (*pskb)->len - extoff);
201 if (protoff < 0 || protoff > (*pskb)->len ||
202 pnum == NEXTHDR_FRAGMENT) {
203 DEBUGP("proto header not found\n");
207 ret = help->helper->help(pskb, protoff, ct, ctinfo);
208 if (ret != NF_ACCEPT)
211 /* We've seen it coming out the other side: confirm it */
212 return nf_conntrack_confirm(pskb);
215 extern struct sk_buff *nf_ct_frag6_gather(struct sk_buff *skb);
216 extern void nf_ct_frag6_output(unsigned int hooknum, struct sk_buff *skb,
217 struct net_device *in,
218 struct net_device *out,
219 int (*okfn)(struct sk_buff *));
220 static unsigned int ipv6_defrag(unsigned int hooknum,
221 struct sk_buff **pskb,
222 const struct net_device *in,
223 const struct net_device *out,
224 int (*okfn)(struct sk_buff *))
226 struct sk_buff *reasm;
228 /* Previously seen (loopback)? */
232 reasm = nf_ct_frag6_gather(*pskb);
238 /* error occured or not fragmented */
242 nf_ct_frag6_output(hooknum, reasm, (struct net_device *)in,
243 (struct net_device *)out, okfn);
248 static unsigned int ipv6_conntrack_in(unsigned int hooknum,
249 struct sk_buff **pskb,
250 const struct net_device *in,
251 const struct net_device *out,
252 int (*okfn)(struct sk_buff *))
254 struct sk_buff *reasm = (*pskb)->nfct_reasm;
256 /* This packet is fragmented and has reassembled packet. */
258 /* Reassembled packet isn't parsed yet ? */
262 ret = nf_conntrack_in(PF_INET6, hooknum, &reasm);
263 if (ret != NF_ACCEPT)
266 nf_conntrack_get(reasm->nfct);
267 (*pskb)->nfct = reasm->nfct;
271 return nf_conntrack_in(PF_INET6, hooknum, pskb);
274 static unsigned int ipv6_conntrack_local(unsigned int hooknum,
275 struct sk_buff **pskb,
276 const struct net_device *in,
277 const struct net_device *out,
278 int (*okfn)(struct sk_buff *))
280 /* root is playing with raw sockets. */
281 if ((*pskb)->len < sizeof(struct ipv6hdr)) {
283 printk("ipv6_conntrack_local: packet too short\n");
286 return ipv6_conntrack_in(hooknum, pskb, in, out, okfn);
289 /* Connection tracking may drop packets, but never alters them, so
290 make it the first hook. */
291 static struct nf_hook_ops ipv6_conntrack_defrag_ops = {
293 .owner = THIS_MODULE,
295 .hooknum = NF_IP6_PRE_ROUTING,
296 .priority = NF_IP6_PRI_CONNTRACK_DEFRAG,
299 static struct nf_hook_ops ipv6_conntrack_in_ops = {
300 .hook = ipv6_conntrack_in,
301 .owner = THIS_MODULE,
303 .hooknum = NF_IP6_PRE_ROUTING,
304 .priority = NF_IP6_PRI_CONNTRACK,
307 static struct nf_hook_ops ipv6_conntrack_local_out_ops = {
308 .hook = ipv6_conntrack_local,
309 .owner = THIS_MODULE,
311 .hooknum = NF_IP6_LOCAL_OUT,
312 .priority = NF_IP6_PRI_CONNTRACK,
315 static struct nf_hook_ops ipv6_conntrack_defrag_local_out_ops = {
317 .owner = THIS_MODULE,
319 .hooknum = NF_IP6_LOCAL_OUT,
320 .priority = NF_IP6_PRI_CONNTRACK_DEFRAG,
323 /* Refragmenter; last chance. */
324 static struct nf_hook_ops ipv6_conntrack_out_ops = {
325 .hook = ipv6_confirm,
326 .owner = THIS_MODULE,
328 .hooknum = NF_IP6_POST_ROUTING,
329 .priority = NF_IP6_PRI_LAST,
332 static struct nf_hook_ops ipv6_conntrack_local_in_ops = {
333 .hook = ipv6_confirm,
334 .owner = THIS_MODULE,
336 .hooknum = NF_IP6_LOCAL_IN,
337 .priority = NF_IP6_PRI_LAST-1,
342 /* From nf_conntrack_proto_icmpv6.c */
343 extern unsigned int nf_ct_icmpv6_timeout;
345 /* From nf_conntrack_frag6.c */
346 extern unsigned int nf_ct_frag6_timeout;
347 extern unsigned int nf_ct_frag6_low_thresh;
348 extern unsigned int nf_ct_frag6_high_thresh;
350 static struct ctl_table_header *nf_ct_ipv6_sysctl_header;
352 static ctl_table nf_ct_sysctl_table[] = {
354 .ctl_name = NET_NF_CONNTRACK_ICMPV6_TIMEOUT,
355 .procname = "nf_conntrack_icmpv6_timeout",
356 .data = &nf_ct_icmpv6_timeout,
357 .maxlen = sizeof(unsigned int),
359 .proc_handler = &proc_dointvec_jiffies,
362 .ctl_name = NET_NF_CONNTRACK_FRAG6_TIMEOUT,
363 .procname = "nf_conntrack_frag6_timeout",
364 .data = &nf_ct_frag6_timeout,
365 .maxlen = sizeof(unsigned int),
367 .proc_handler = &proc_dointvec_jiffies,
370 .ctl_name = NET_NF_CONNTRACK_FRAG6_LOW_THRESH,
371 .procname = "nf_conntrack_frag6_low_thresh",
372 .data = &nf_ct_frag6_low_thresh,
373 .maxlen = sizeof(unsigned int),
375 .proc_handler = &proc_dointvec,
378 .ctl_name = NET_NF_CONNTRACK_FRAG6_HIGH_THRESH,
379 .procname = "nf_conntrack_frag6_high_thresh",
380 .data = &nf_ct_frag6_high_thresh,
381 .maxlen = sizeof(unsigned int),
383 .proc_handler = &proc_dointvec,
388 static ctl_table nf_ct_netfilter_table[] = {
390 .ctl_name = NET_NETFILTER,
391 .procname = "netfilter",
393 .child = nf_ct_sysctl_table,
398 static ctl_table nf_ct_net_table[] = {
403 .child = nf_ct_netfilter_table,
409 #if defined(CONFIG_NF_CT_NETLINK) || \
410 defined(CONFIG_NF_CT_NETLINK_MODULE)
412 #include <linux/netfilter/nfnetlink.h>
413 #include <linux/netfilter/nfnetlink_conntrack.h>
415 static int ipv6_tuple_to_nfattr(struct sk_buff *skb,
416 const struct nf_conntrack_tuple *tuple)
418 NFA_PUT(skb, CTA_IP_V6_SRC, sizeof(u_int32_t) * 4,
420 NFA_PUT(skb, CTA_IP_V6_DST, sizeof(u_int32_t) * 4,
428 static const size_t cta_min_ip[CTA_IP_MAX] = {
429 [CTA_IP_V6_SRC-1] = sizeof(u_int32_t)*4,
430 [CTA_IP_V6_DST-1] = sizeof(u_int32_t)*4,
433 static int ipv6_nfattr_to_tuple(struct nfattr *tb[],
434 struct nf_conntrack_tuple *t)
436 if (!tb[CTA_IP_V6_SRC-1] || !tb[CTA_IP_V6_DST-1])
439 if (nfattr_bad_size(tb, CTA_IP_MAX, cta_min_ip))
442 memcpy(&t->src.u3.ip6, NFA_DATA(tb[CTA_IP_V6_SRC-1]),
443 sizeof(u_int32_t) * 4);
444 memcpy(&t->dst.u3.ip6, NFA_DATA(tb[CTA_IP_V6_DST-1]),
445 sizeof(u_int32_t) * 4);
451 struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 = {
454 .pkt_to_tuple = ipv6_pkt_to_tuple,
455 .invert_tuple = ipv6_invert_tuple,
456 .print_tuple = ipv6_print_tuple,
457 .print_conntrack = ipv6_print_conntrack,
458 .prepare = ipv6_prepare,
459 #if defined(CONFIG_NF_CT_NETLINK) || \
460 defined(CONFIG_NF_CT_NETLINK_MODULE)
461 .tuple_to_nfattr = ipv6_tuple_to_nfattr,
462 .nfattr_to_tuple = ipv6_nfattr_to_tuple,
464 .get_features = ipv6_get_features,
468 extern struct nf_conntrack_protocol nf_conntrack_protocol_tcp6;
469 extern struct nf_conntrack_protocol nf_conntrack_protocol_udp6;
470 extern struct nf_conntrack_protocol nf_conntrack_protocol_icmpv6;
471 extern int nf_ct_frag6_init(void);
472 extern void nf_ct_frag6_cleanup(void);
473 static int init_or_cleanup(int init)
477 if (!init) goto cleanup;
479 ret = nf_ct_frag6_init();
481 printk("nf_conntrack_ipv6: can't initialize frag6.\n");
482 goto cleanup_nothing;
484 ret = nf_conntrack_protocol_register(&nf_conntrack_protocol_tcp6);
486 printk("nf_conntrack_ipv6: can't register tcp.\n");
490 ret = nf_conntrack_protocol_register(&nf_conntrack_protocol_udp6);
492 printk("nf_conntrack_ipv6: can't register udp.\n");
496 ret = nf_conntrack_protocol_register(&nf_conntrack_protocol_icmpv6);
498 printk("nf_conntrack_ipv6: can't register icmpv6.\n");
502 ret = nf_conntrack_l3proto_register(&nf_conntrack_l3proto_ipv6);
504 printk("nf_conntrack_ipv6: can't register ipv6\n");
508 ret = nf_register_hook(&ipv6_conntrack_defrag_ops);
510 printk("nf_conntrack_ipv6: can't register pre-routing defrag "
515 ret = nf_register_hook(&ipv6_conntrack_defrag_local_out_ops);
517 printk("nf_conntrack_ipv6: can't register local_out defrag "
519 goto cleanup_defragops;
522 ret = nf_register_hook(&ipv6_conntrack_in_ops);
524 printk("nf_conntrack_ipv6: can't register pre-routing hook.\n");
525 goto cleanup_defraglocalops;
528 ret = nf_register_hook(&ipv6_conntrack_local_out_ops);
530 printk("nf_conntrack_ipv6: can't register local out hook.\n");
534 ret = nf_register_hook(&ipv6_conntrack_out_ops);
536 printk("nf_conntrack_ipv6: can't register post-routing hook.\n");
537 goto cleanup_inandlocalops;
540 ret = nf_register_hook(&ipv6_conntrack_local_in_ops);
542 printk("nf_conntrack_ipv6: can't register local in hook.\n");
543 goto cleanup_inoutandlocalops;
547 nf_ct_ipv6_sysctl_header = register_sysctl_table(nf_ct_net_table, 0);
548 if (nf_ct_ipv6_sysctl_header == NULL) {
549 printk("nf_conntrack: can't register to sysctl.\n");
551 goto cleanup_localinops;
559 unregister_sysctl_table(nf_ct_ipv6_sysctl_header);
562 nf_unregister_hook(&ipv6_conntrack_local_in_ops);
563 cleanup_inoutandlocalops:
564 nf_unregister_hook(&ipv6_conntrack_out_ops);
565 cleanup_inandlocalops:
566 nf_unregister_hook(&ipv6_conntrack_local_out_ops);
568 nf_unregister_hook(&ipv6_conntrack_in_ops);
569 cleanup_defraglocalops:
570 nf_unregister_hook(&ipv6_conntrack_defrag_local_out_ops);
572 nf_unregister_hook(&ipv6_conntrack_defrag_ops);
574 nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
576 nf_conntrack_protocol_unregister(&nf_conntrack_protocol_icmpv6);
578 nf_conntrack_protocol_unregister(&nf_conntrack_protocol_udp6);
580 nf_conntrack_protocol_unregister(&nf_conntrack_protocol_tcp6);
582 nf_ct_frag6_cleanup();
587 MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6));
588 MODULE_LICENSE("GPL");
589 MODULE_AUTHOR("Yasuyuki KOZAKAI @USAGI <yasuyuki.kozakai@toshiba.co.jp>");
591 static int __init nf_conntrack_l3proto_ipv6_init(void)
594 return init_or_cleanup(1);
597 static void __exit nf_conntrack_l3proto_ipv6_fini(void)
602 module_init(nf_conntrack_l3proto_ipv6_init);
603 module_exit(nf_conntrack_l3proto_ipv6_fini);