[linux-2.6-block.git] / net / ipv6 / netfilter / nf_conntrack_l3proto_ipv6.c

/*
 * Copyright (C)2004 USAGI/WIDE Project
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Author:
 *	Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
 */

#include <linux/types.h>
#include <linux/ipv6.h>
#include <linux/in6.h>
#include <linux/netfilter.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/icmp.h>
#include <linux/sysctl.h>
#include <net/ipv6.h>
#include <net/inet_frag.h>

#include <linux/netfilter_ipv6.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_helper.h>
#include <net/netfilter/nf_conntrack_l4proto.h>
#include <net/netfilter/nf_conntrack_l3proto.h>
#include <net/netfilter/nf_conntrack_core.h>

static bool ipv6_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff,
			      struct nf_conntrack_tuple *tuple)
{
	const u_int32_t *ap;
	u_int32_t _addrs[8];

	ap = skb_header_pointer(skb, nhoff + offsetof(struct ipv6hdr, saddr),
				sizeof(_addrs), _addrs);
	if (ap == NULL)
		return false;

	memcpy(tuple->src.u3.ip6, ap, sizeof(tuple->src.u3.ip6));
	memcpy(tuple->dst.u3.ip6, ap + 4, sizeof(tuple->dst.u3.ip6));

	return true;
}

static bool ipv6_invert_tuple(struct nf_conntrack_tuple *tuple,
			      const struct nf_conntrack_tuple *orig)
{
	memcpy(tuple->src.u3.ip6, orig->dst.u3.ip6, sizeof(tuple->src.u3.ip6));
	memcpy(tuple->dst.u3.ip6, orig->src.u3.ip6, sizeof(tuple->dst.u3.ip6));

	return true;
}

static int ipv6_print_tuple(struct seq_file *s,
			    const struct nf_conntrack_tuple *tuple)
{
	return seq_printf(s, "src=" NIP6_FMT " dst=" NIP6_FMT " ",
			  NIP6(*((struct in6_addr *)tuple->src.u3.ip6)),
			  NIP6(*((struct in6_addr *)tuple->dst.u3.ip6)));
}

/*
 * Based on ipv6_skip_exthdr() in net/ipv6/exthdr.c
 *
 * This function parses (probably truncated) exthdr set "hdr"
 * of length "len". "nexthdrp" initially points to some place,
 * where type of the first header can be found.
 *
 * It skips all well-known exthdrs, and returns pointer to the start
 * of unparsable area i.e. the first header with unknown type.
 * if success, *nexthdr is updated by type/protocol of this header.
 *
 * NOTES: - it may return pointer pointing beyond end of packet,
 *          if the last recognized header is truncated in the middle.
 *        - if packet is truncated, so that all parsed headers are skipped,
 *          it returns -1.
 *        - if packet is fragmented, return pointer of the fragment header.
 *        - ESP is unparsable for now and considered like
 *          normal payload protocol.
 *        - Note also special handling of AUTH header. Thanks to IPsec wizards.
 */

static int nf_ct_ipv6_skip_exthdr(const struct sk_buff *skb, int start,
				  u8 *nexthdrp, int len)
{
	u8 nexthdr = *nexthdrp;

	while (ipv6_ext_hdr(nexthdr)) {
		struct ipv6_opt_hdr hdr;
		int hdrlen;

		if (len < (int)sizeof(struct ipv6_opt_hdr))
			return -1;
		if (nexthdr == NEXTHDR_NONE)
			break;
		if (nexthdr == NEXTHDR_FRAGMENT)
			break;
		if (skb_copy_bits(skb, start, &hdr, sizeof(hdr)))
			BUG();
		if (nexthdr == NEXTHDR_AUTH)
			hdrlen = (hdr.hdrlen+2)<<2;
		else
			hdrlen = ipv6_optlen(&hdr);

		nexthdr = hdr.nexthdr;
		len -= hdrlen;
		start += hdrlen;
	}

	*nexthdrp = nexthdr;
	return start;
}

static int ipv6_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
			    unsigned int *dataoff, u_int8_t *protonum)
{
	unsigned int extoff = nhoff + sizeof(struct ipv6hdr);
	unsigned char pnum;
	int protoff;

	if (skb_copy_bits(skb, nhoff + offsetof(struct ipv6hdr, nexthdr),
			  &pnum, sizeof(pnum)) != 0) {
		pr_debug("ip6_conntrack_core: can't get nexthdr\n");
		return -NF_ACCEPT;
	}
	protoff = nf_ct_ipv6_skip_exthdr(skb, extoff, &pnum, skb->len - extoff);
	/*
	 * (protoff == skb->len) mean that the packet doesn't have no data
	 * except of IPv6 & ext headers. but it's tracked anyway. - YK
	 */
	if ((protoff < 0) || (protoff > skb->len)) {
		pr_debug("ip6_conntrack_core: can't find proto in pkt\n");
		return -NF_ACCEPT;
	}

	*dataoff = protoff;
	*protonum = pnum;
	return NF_ACCEPT;
}

static unsigned int ipv6_confirm(unsigned int hooknum,
				 struct sk_buff *skb,
				 const struct net_device *in,
				 const struct net_device *out,
				 int (*okfn)(struct sk_buff *))
{
	struct nf_conn *ct;
	const struct nf_conn_help *help;
	const struct nf_conntrack_helper *helper;
	enum ip_conntrack_info ctinfo;
	unsigned int ret, protoff;
	unsigned int extoff = (u8 *)(ipv6_hdr(skb) + 1) - skb->data;
	unsigned char pnum = ipv6_hdr(skb)->nexthdr;


	/* This is where we call the helper: as the packet goes out. */
	ct = nf_ct_get(skb, &ctinfo);
	if (!ct || ctinfo == IP_CT_RELATED + IP_CT_IS_REPLY)
		goto out;

	help = nfct_help(ct);
	if (!help)
		goto out;
	/* rcu_read_lock()ed by nf_hook_slow */
	helper = rcu_dereference(help->helper);
	if (!helper)
		goto out;

	protoff = nf_ct_ipv6_skip_exthdr(skb, extoff, &pnum,
					 skb->len - extoff);
	if (protoff > skb->len || pnum == NEXTHDR_FRAGMENT) {
		pr_debug("proto header not found\n");
		return NF_ACCEPT;
	}

	ret = helper->help(skb, protoff, ct, ctinfo);
	if (ret != NF_ACCEPT)
		return ret;
out:
	/* We've seen it coming out the other side: confirm it */
	return nf_conntrack_confirm(skb);
}

static unsigned int ipv6_defrag(unsigned int hooknum,
				struct sk_buff *skb,
				const struct net_device *in,
				const struct net_device *out,
				int (*okfn)(struct sk_buff *))
{
	struct sk_buff *reasm;

	/* Previously seen (loopback)?  */
	if (skb->nfct)
		return NF_ACCEPT;

	reasm = nf_ct_frag6_gather(skb);

	/* queued */
	if (reasm == NULL)
		return NF_STOLEN;

	/* error occured or not fragmented */
	if (reasm == skb)
		return NF_ACCEPT;

	nf_ct_frag6_output(hooknum, reasm, (struct net_device *)in,
			   (struct net_device *)out, okfn);

	return NF_STOLEN;
}

static unsigned int __ipv6_conntrack_in(struct net *net,
					unsigned int hooknum,
					struct sk_buff *skb,
					int (*okfn)(struct sk_buff *))
{
	struct sk_buff *reasm = skb->nfct_reasm;

	/* This packet is fragmented and has reassembled packet. */
	if (reasm) {
		/* Reassembled packet isn't parsed yet ? */
		if (!reasm->nfct) {
			unsigned int ret;

			ret = nf_conntrack_in(net, PF_INET6, hooknum, reasm);
			if (ret != NF_ACCEPT)
				return ret;
		}
		nf_conntrack_get(reasm->nfct);
		skb->nfct = reasm->nfct;
		skb->nfctinfo = reasm->nfctinfo;
		return NF_ACCEPT;
	}

	return nf_conntrack_in(net, PF_INET6, hooknum, skb);
}

static unsigned int ipv6_conntrack_in(unsigned int hooknum,
				      struct sk_buff *skb,
				      const struct net_device *in,
				      const struct net_device *out,
				      int (*okfn)(struct sk_buff *))
{
	return __ipv6_conntrack_in(dev_net(in), hooknum, skb, okfn);
}

static unsigned int ipv6_conntrack_local(unsigned int hooknum,
					 struct sk_buff *skb,
					 const struct net_device *in,
					 const struct net_device *out,
					 int (*okfn)(struct sk_buff *))
{
	/* root is playing with raw sockets. */
	if (skb->len < sizeof(struct ipv6hdr)) {
		if (net_ratelimit())
			printk("ipv6_conntrack_local: packet too short\n");
		return NF_ACCEPT;
	}
	return __ipv6_conntrack_in(dev_net(out), hooknum, skb, okfn);
}

static struct nf_hook_ops ipv6_conntrack_ops[] __read_mostly = {
	{
		.hook		= ipv6_defrag,
		.owner		= THIS_MODULE,
		.pf		= PF_INET6,
		.hooknum	= NF_INET_PRE_ROUTING,
		.priority	= NF_IP6_PRI_CONNTRACK_DEFRAG,
	},
	{
		.hook		= ipv6_conntrack_in,
		.owner		= THIS_MODULE,
		.pf		= PF_INET6,
		.hooknum	= NF_INET_PRE_ROUTING,
		.priority	= NF_IP6_PRI_CONNTRACK,
	},
	{
		.hook		= ipv6_conntrack_local,
		.owner		= THIS_MODULE,
		.pf		= PF_INET6,
		.hooknum	= NF_INET_LOCAL_OUT,
		.priority	= NF_IP6_PRI_CONNTRACK,
	},
	{
		.hook		= ipv6_defrag,
		.owner		= THIS_MODULE,
		.pf		= PF_INET6,
		.hooknum	= NF_INET_LOCAL_OUT,
		.priority	= NF_IP6_PRI_CONNTRACK_DEFRAG,
	},
	{
		.hook		= ipv6_confirm,
		.owner		= THIS_MODULE,
		.pf		= PF_INET6,
		.hooknum	= NF_INET_POST_ROUTING,
		.priority	= NF_IP6_PRI_LAST,
	},
	{
		.hook		= ipv6_confirm,
		.owner		= THIS_MODULE,
		.pf		= PF_INET6,
		.hooknum	= NF_INET_LOCAL_IN,
		.priority	= NF_IP6_PRI_LAST-1,
	},
};

#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)

#include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/nfnetlink_conntrack.h>

static int ipv6_tuple_to_nlattr(struct sk_buff *skb,
				const struct nf_conntrack_tuple *tuple)
{
	NLA_PUT(skb, CTA_IP_V6_SRC, sizeof(u_int32_t) * 4,
		&tuple->src.u3.ip6);
	NLA_PUT(skb, CTA_IP_V6_DST, sizeof(u_int32_t) * 4,
		&tuple->dst.u3.ip6);
	return 0;

nla_put_failure:
	return -1;
}

static const struct nla_policy ipv6_nla_policy[CTA_IP_MAX+1] = {
	[CTA_IP_V6_SRC]	= { .len = sizeof(u_int32_t)*4 },
	[CTA_IP_V6_DST]	= { .len = sizeof(u_int32_t)*4 },
};

static int ipv6_nlattr_to_tuple(struct nlattr *tb[],
				struct nf_conntrack_tuple *t)
{
	if (!tb[CTA_IP_V6_SRC] || !tb[CTA_IP_V6_DST])
		return -EINVAL;

	memcpy(&t->src.u3.ip6, nla_data(tb[CTA_IP_V6_SRC]),
	       sizeof(u_int32_t) * 4);
	memcpy(&t->dst.u3.ip6, nla_data(tb[CTA_IP_V6_DST]),
	       sizeof(u_int32_t) * 4);

	return 0;
}
#endif

struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 __read_mostly = {
	.l3proto		= PF_INET6,
	.name			= "ipv6",
	.pkt_to_tuple		= ipv6_pkt_to_tuple,
	.invert_tuple		= ipv6_invert_tuple,
	.print_tuple		= ipv6_print_tuple,
	.get_l4proto		= ipv6_get_l4proto,
#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
	.tuple_to_nlattr	= ipv6_tuple_to_nlattr,
	.nlattr_to_tuple	= ipv6_nlattr_to_tuple,
	.nla_policy		= ipv6_nla_policy,
#endif
#ifdef CONFIG_SYSCTL
	.ctl_table_path		= nf_net_netfilter_sysctl_path,
	.ctl_table		= nf_ct_ipv6_sysctl_table,
#endif
	.me			= THIS_MODULE,
};

MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6));
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Yasuyuki KOZAKAI @USAGI <yasuyuki.kozakai@toshiba.co.jp>");

static int __init nf_conntrack_l3proto_ipv6_init(void)
{
	int ret = 0;

	need_conntrack();

	ret = nf_ct_frag6_init();
	if (ret < 0) {
		printk("nf_conntrack_ipv6: can't initialize frag6.\n");
		return ret;
	}
	ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_tcp6);
	if (ret < 0) {
		printk("nf_conntrack_ipv6: can't register tcp.\n");
		goto cleanup_frag6;
	}

	ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_udp6);
	if (ret < 0) {
		printk("nf_conntrack_ipv6: can't register udp.\n");
		goto cleanup_tcp;
	}

	ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_icmpv6);
	if (ret < 0) {
		printk("nf_conntrack_ipv6: can't register icmpv6.\n");
		goto cleanup_udp;
	}

	ret = nf_conntrack_l3proto_register(&nf_conntrack_l3proto_ipv6);
	if (ret < 0) {
		printk("nf_conntrack_ipv6: can't register ipv6\n");
		goto cleanup_icmpv6;
	}

	ret = nf_register_hooks(ipv6_conntrack_ops,
				ARRAY_SIZE(ipv6_conntrack_ops));
	if (ret < 0) {
		printk("nf_conntrack_ipv6: can't register pre-routing defrag "
		       "hook.\n");
		goto cleanup_ipv6;
	}
	return ret;

 cleanup_ipv6:
	nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
 cleanup_icmpv6:
	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6);
 cleanup_udp:
	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6);
 cleanup_tcp:
	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6);
 cleanup_frag6:
	nf_ct_frag6_cleanup();
	return ret;
}

static void __exit nf_conntrack_l3proto_ipv6_fini(void)
{
	synchronize_net();
	nf_unregister_hooks(ipv6_conntrack_ops, ARRAY_SIZE(ipv6_conntrack_ops));
	nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6);
	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6);
	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6);
	nf_ct_frag6_cleanup();
}

module_init(nf_conntrack_l3proto_ipv6_init);
module_exit(nf_conntrack_l3proto_ipv6_fini);
Commit	Line	Data
9fb9cbb1 YK	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>
9fb9cbb1 YK	10	*/
9fb9cbb1 YK	11
9fb9cbb1 YK	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 <linux/sysctl.h>
	20	#include <net/ipv6.h>
04128f23	21	#include <net/inet_frag.h>
9fb9cbb1 YK	22
	23	#include <linux/netfilter_ipv6.h>
	24	#include <net/netfilter/nf_conntrack.h>
	25	#include <net/netfilter/nf_conntrack_helper.h>
605dcad6	26	#include <net/netfilter/nf_conntrack_l4proto.h>
9fb9cbb1 YK	27	#include <net/netfilter/nf_conntrack_l3proto.h>
	28	#include <net/netfilter/nf_conntrack_core.h>
	29
8ce8439a JE	30	static bool ipv6_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff,
8ce8439a JE	31	struct nf_conntrack_tuple *tuple)
9fb9cbb1	32	{
32948588 JE	33	const u_int32_t *ap;
32948588 JE	34	u_int32_t _addrs[8];
9fb9cbb1 YK	35
	36	ap = skb_header_pointer(skb, nhoff + offsetof(struct ipv6hdr, saddr),
	37	sizeof(_addrs), _addrs);
	38	if (ap == NULL)
8ce8439a	39	return false;
9fb9cbb1 YK	40
	41	memcpy(tuple->src.u3.ip6, ap, sizeof(tuple->src.u3.ip6));
	42	memcpy(tuple->dst.u3.ip6, ap + 4, sizeof(tuple->dst.u3.ip6));
	43
8ce8439a	44	return true;
9fb9cbb1 YK	45	}
9fb9cbb1 YK	46
8ce8439a JE	47	static bool ipv6_invert_tuple(struct nf_conntrack_tuple *tuple,
8ce8439a JE	48	const struct nf_conntrack_tuple *orig)
9fb9cbb1 YK	49	{
	50	memcpy(tuple->src.u3.ip6, orig->dst.u3.ip6, sizeof(tuple->src.u3.ip6));
	51	memcpy(tuple->dst.u3.ip6, orig->src.u3.ip6, sizeof(tuple->dst.u3.ip6));
	52
8ce8439a	53	return true;
9fb9cbb1 YK	54	}
	55
	56	static int ipv6_print_tuple(struct seq_file *s,
	57	const struct nf_conntrack_tuple *tuple)
	58	{
46b86a2d	59	return seq_printf(s, "src=" NIP6_FMT " dst=" NIP6_FMT " ",
9fb9cbb1 YK	60	NIP6(((struct in6_addr )tuple->src.u3.ip6)),
	61	NIP6(((struct in6_addr )tuple->dst.u3.ip6)));
	62	}
	63
9fb9cbb1 YK	64	/*
	65	* Based on ipv6_skip_exthdr() in net/ipv6/exthdr.c
	66	*
	67	* This function parses (probably truncated) exthdr set "hdr"
	68	* of length "len". "nexthdrp" initially points to some place,
	69	* where type of the first header can be found.
	70	*
	71	* It skips all well-known exthdrs, and returns pointer to the start
	72	* of unparsable area i.e. the first header with unknown type.
	73	* if success, *nexthdr is updated by type/protocol of this header.
	74	*
	75	* NOTES: - it may return pointer pointing beyond end of packet,
	76	* if the last recognized header is truncated in the middle.
	77	* - if packet is truncated, so that all parsed headers are skipped,
	78	* it returns -1.
	79	* - if packet is fragmented, return pointer of the fragment header.
	80	* - ESP is unparsable for now and considered like
	81	* normal payload protocol.
	82	* - Note also special handling of AUTH header. Thanks to IPsec wizards.
	83	*/
	84
1a3a206f AB	85	static int nf_ct_ipv6_skip_exthdr(const struct sk_buff *skb, int start,
1a3a206f AB	86	u8 *nexthdrp, int len)
9fb9cbb1 YK	87	{
	88	u8 nexthdr = *nexthdrp;
	89
	90	while (ipv6_ext_hdr(nexthdr)) {
	91	struct ipv6_opt_hdr hdr;
	92	int hdrlen;
	93
	94	if (len < (int)sizeof(struct ipv6_opt_hdr))
	95	return -1;
	96	if (nexthdr == NEXTHDR_NONE)
	97	break;
	98	if (nexthdr == NEXTHDR_FRAGMENT)
	99	break;
	100	if (skb_copy_bits(skb, start, &hdr, sizeof(hdr)))
	101	BUG();
	102	if (nexthdr == NEXTHDR_AUTH)
	103	hdrlen = (hdr.hdrlen+2)<<2;
	104	else
	105	hdrlen = ipv6_optlen(&hdr);
	106
	107	nexthdr = hdr.nexthdr;
	108	len -= hdrlen;
	109	start += hdrlen;
	110	}
	111
	112	*nexthdrp = nexthdr;
	113	return start;
	114	}
	115
ffc30690 YK	116	static int ipv6_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
ffc30690 YK	117	unsigned int dataoff, u_int8_t protonum)
9fb9cbb1	118	{
ffc30690 YK	119	unsigned int extoff = nhoff + sizeof(struct ipv6hdr);
	120	unsigned char pnum;
	121	int protoff;
	122
	123	if (skb_copy_bits(skb, nhoff + offsetof(struct ipv6hdr, nexthdr),
	124	&pnum, sizeof(pnum)) != 0) {
	125	pr_debug("ip6_conntrack_core: can't get nexthdr\n");
	126	return -NF_ACCEPT;
	127	}
	128	protoff = nf_ct_ipv6_skip_exthdr(skb, extoff, &pnum, skb->len - extoff);
9fb9cbb1	129	/*
ffc30690	130	* (protoff == skb->len) mean that the packet doesn't have no data
9fb9cbb1 YK	131	* except of IPv6 & ext headers. but it's tracked anyway. - YK
9fb9cbb1 YK	132	*/
ffc30690	133	if ((protoff < 0) \|\| (protoff > skb->len)) {
0d53778e	134	pr_debug("ip6_conntrack_core: can't find proto in pkt\n");
9fb9cbb1 YK	135	return -NF_ACCEPT;
	136	}
	137
	138	*dataoff = protoff;
	139	*protonum = pnum;
	140	return NF_ACCEPT;
	141	}
	142
9fb9cbb1	143	static unsigned int ipv6_confirm(unsigned int hooknum,
3db05fea	144	struct sk_buff *skb,
9fb9cbb1 YK	145	const struct net_device *in,
	146	const struct net_device *out,
	147	int (okfn)(struct sk_buff ))
	148	{
	149	struct nf_conn *ct;
32948588 JE	150	const struct nf_conn_help *help;
32948588 JE	151	const struct nf_conntrack_helper *helper;
9fb9cbb1	152	enum ip_conntrack_info ctinfo;
dc808fe2	153	unsigned int ret, protoff;
3db05fea HX	154	unsigned int extoff = (u8 *)(ipv6_hdr(skb) + 1) - skb->data;
3db05fea HX	155	unsigned char pnum = ipv6_hdr(skb)->nexthdr;
dc808fe2	156
9fb9cbb1 YK	157
9fb9cbb1 YK	158	/* This is where we call the helper: as the packet goes out. */
3db05fea	159	ct = nf_ct_get(skb, &ctinfo);
6442f1cf	160	if (!ct \|\| ctinfo == IP_CT_RELATED + IP_CT_IS_REPLY)
dc808fe2 HW	161	goto out;
	162
	163	help = nfct_help(ct);
3c158f7f PM	164	if (!help)
	165	goto out;
	166	/* rcu_read_lock()ed by nf_hook_slow */
	167	helper = rcu_dereference(help->helper);
	168	if (!helper)
dc808fe2 HW	169	goto out;
dc808fe2 HW	170
3db05fea HX	171	protoff = nf_ct_ipv6_skip_exthdr(skb, extoff, &pnum,
	172	skb->len - extoff);
	173	if (protoff > skb->len \|\| pnum == NEXTHDR_FRAGMENT) {
0d53778e	174	pr_debug("proto header not found\n");
dc808fe2	175	return NF_ACCEPT;
9fb9cbb1 YK	176	}
9fb9cbb1 YK	177
3db05fea	178	ret = helper->help(skb, protoff, ct, ctinfo);
dc808fe2 HW	179	if (ret != NF_ACCEPT)
	180	return ret;
	181	out:
9fb9cbb1	182	/* We've seen it coming out the other side: confirm it */
3db05fea	183	return nf_conntrack_confirm(skb);
9fb9cbb1 YK	184	}
9fb9cbb1 YK	185
9fb9cbb1	186	static unsigned int ipv6_defrag(unsigned int hooknum,
3db05fea	187	struct sk_buff *skb,
9fb9cbb1 YK	188	const struct net_device *in,
	189	const struct net_device *out,
	190	int (okfn)(struct sk_buff ))
	191	{
	192	struct sk_buff *reasm;
	193
	194	/* Previously seen (loopback)? */
3db05fea	195	if (skb->nfct)
9fb9cbb1 YK	196	return NF_ACCEPT;
9fb9cbb1 YK	197
3db05fea	198	reasm = nf_ct_frag6_gather(skb);
9fb9cbb1 YK	199
	200	/* queued */
	201	if (reasm == NULL)
	202	return NF_STOLEN;
	203
	204	/* error occured or not fragmented */
3db05fea	205	if (reasm == skb)
9fb9cbb1 YK	206	return NF_ACCEPT;
	207
	208	nf_ct_frag6_output(hooknum, reasm, (struct net_device *)in,
	209	(struct net_device *)out, okfn);
	210
	211	return NF_STOLEN;
	212	}
	213
a702a65f AD	214	static unsigned int __ipv6_conntrack_in(struct net *net,
	215	unsigned int hooknum,
	216	struct sk_buff *skb,
	217	int (okfn)(struct sk_buff ))
9fb9cbb1	218	{
3db05fea	219	struct sk_buff *reasm = skb->nfct_reasm;
9fb9cbb1 YK	220
	221	/* This packet is fragmented and has reassembled packet. */
	222	if (reasm) {
	223	/* Reassembled packet isn't parsed yet ? */
	224	if (!reasm->nfct) {
	225	unsigned int ret;
	226
a702a65f	227	ret = nf_conntrack_in(net, PF_INET6, hooknum, reasm);
9fb9cbb1 YK	228	if (ret != NF_ACCEPT)
	229	return ret;
	230	}
	231	nf_conntrack_get(reasm->nfct);
3db05fea HX	232	skb->nfct = reasm->nfct;
3db05fea HX	233	skb->nfctinfo = reasm->nfctinfo;
9fb9cbb1 YK	234	return NF_ACCEPT;
	235	}
	236
a702a65f AD	237	return nf_conntrack_in(net, PF_INET6, hooknum, skb);
	238	}
	239
	240	static unsigned int ipv6_conntrack_in(unsigned int hooknum,
	241	struct sk_buff *skb,
	242	const struct net_device *in,
	243	const struct net_device *out,
	244	int (okfn)(struct sk_buff ))
	245	{
	246	return __ipv6_conntrack_in(dev_net(in), hooknum, skb, okfn);
9fb9cbb1 YK	247	}
	248
	249	static unsigned int ipv6_conntrack_local(unsigned int hooknum,
3db05fea	250	struct sk_buff *skb,
9fb9cbb1 YK	251	const struct net_device *in,
	252	const struct net_device *out,
	253	int (okfn)(struct sk_buff ))
	254	{
	255	/* root is playing with raw sockets. */
3db05fea	256	if (skb->len < sizeof(struct ipv6hdr)) {
9fb9cbb1 YK	257	if (net_ratelimit())
	258	printk("ipv6_conntrack_local: packet too short\n");
	259	return NF_ACCEPT;
	260	}
a702a65f	261	return __ipv6_conntrack_in(dev_net(out), hooknum, skb, okfn);
9fb9cbb1 YK	262	}
9fb9cbb1 YK	263
1999414a	264	static struct nf_hook_ops ipv6_conntrack_ops[] __read_mostly = {
964ddaa1 PM	265	{
	266	.hook = ipv6_defrag,
	267	.owner = THIS_MODULE,
	268	.pf = PF_INET6,
6e23ae2a	269	.hooknum = NF_INET_PRE_ROUTING,
964ddaa1 PM	270	.priority = NF_IP6_PRI_CONNTRACK_DEFRAG,
	271	},
	272	{
	273	.hook = ipv6_conntrack_in,
	274	.owner = THIS_MODULE,
	275	.pf = PF_INET6,
6e23ae2a	276	.hooknum = NF_INET_PRE_ROUTING,
964ddaa1 PM	277	.priority = NF_IP6_PRI_CONNTRACK,
	278	},
	279	{
	280	.hook = ipv6_conntrack_local,
	281	.owner = THIS_MODULE,
	282	.pf = PF_INET6,
6e23ae2a	283	.hooknum = NF_INET_LOCAL_OUT,
964ddaa1 PM	284	.priority = NF_IP6_PRI_CONNTRACK,
	285	},
	286	{
	287	.hook = ipv6_defrag,
	288	.owner = THIS_MODULE,
	289	.pf = PF_INET6,
6e23ae2a	290	.hooknum = NF_INET_LOCAL_OUT,
964ddaa1 PM	291	.priority = NF_IP6_PRI_CONNTRACK_DEFRAG,
	292	},
	293	{
	294	.hook = ipv6_confirm,
	295	.owner = THIS_MODULE,
	296	.pf = PF_INET6,
6e23ae2a	297	.hooknum = NF_INET_POST_ROUTING,
964ddaa1 PM	298	.priority = NF_IP6_PRI_LAST,
	299	},
	300	{
	301	.hook = ipv6_confirm,
	302	.owner = THIS_MODULE,
	303	.pf = PF_INET6,
6e23ae2a	304	.hooknum = NF_INET_LOCAL_IN,
964ddaa1 PM	305	.priority = NF_IP6_PRI_LAST-1,
964ddaa1 PM	306	},
9fb9cbb1 YK	307	};
9fb9cbb1 YK	308
e281db5c	309	#if defined(CONFIG_NF_CT_NETLINK) \|\| defined(CONFIG_NF_CT_NETLINK_MODULE)
c1d10adb PNA	310
	311	#include <linux/netfilter/nfnetlink.h>
	312	#include <linux/netfilter/nfnetlink_conntrack.h>
	313
fdf70832	314	static int ipv6_tuple_to_nlattr(struct sk_buff *skb,
c1d10adb PNA	315	const struct nf_conntrack_tuple *tuple)
c1d10adb PNA	316	{
df6fb868	317	NLA_PUT(skb, CTA_IP_V6_SRC, sizeof(u_int32_t) * 4,
c1d10adb	318	&tuple->src.u3.ip6);
df6fb868	319	NLA_PUT(skb, CTA_IP_V6_DST, sizeof(u_int32_t) * 4,
c1d10adb PNA	320	&tuple->dst.u3.ip6);
	321	return 0;
	322
df6fb868	323	nla_put_failure:
c1d10adb PNA	324	return -1;
	325	}
	326
f73e924c PM	327	static const struct nla_policy ipv6_nla_policy[CTA_IP_MAX+1] = {
	328	[CTA_IP_V6_SRC] = { .len = sizeof(u_int32_t)*4 },
	329	[CTA_IP_V6_DST] = { .len = sizeof(u_int32_t)*4 },
c1d10adb PNA	330	};
c1d10adb PNA	331
fdf70832	332	static int ipv6_nlattr_to_tuple(struct nlattr *tb[],
c1d10adb PNA	333	struct nf_conntrack_tuple *t)
c1d10adb PNA	334	{
df6fb868	335	if (!tb[CTA_IP_V6_SRC] \|\| !tb[CTA_IP_V6_DST])
c1d10adb PNA	336	return -EINVAL;
c1d10adb PNA	337
df6fb868	338	memcpy(&t->src.u3.ip6, nla_data(tb[CTA_IP_V6_SRC]),
c1d10adb	339	sizeof(u_int32_t) * 4);
df6fb868	340	memcpy(&t->dst.u3.ip6, nla_data(tb[CTA_IP_V6_DST]),
c1d10adb PNA	341	sizeof(u_int32_t) * 4);
	342
	343	return 0;
	344	}
	345	#endif
	346
61075af5	347	struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 __read_mostly = {
9fb9cbb1 YK	348	.l3proto = PF_INET6,
	349	.name = "ipv6",
	350	.pkt_to_tuple = ipv6_pkt_to_tuple,
	351	.invert_tuple = ipv6_invert_tuple,
	352	.print_tuple = ipv6_print_tuple,
ffc30690	353	.get_l4proto = ipv6_get_l4proto,
e281db5c	354	#if defined(CONFIG_NF_CT_NETLINK) \|\| defined(CONFIG_NF_CT_NETLINK_MODULE)
fdf70832 PM	355	.tuple_to_nlattr = ipv6_tuple_to_nlattr,
fdf70832 PM	356	.nlattr_to_tuple = ipv6_nlattr_to_tuple,
f73e924c	357	.nla_policy = ipv6_nla_policy,
933a41e7 PM	358	#endif
	359	#ifdef CONFIG_SYSCTL
	360	.ctl_table_path = nf_net_netfilter_sysctl_path,
	361	.ctl_table = nf_ct_ipv6_sysctl_table,
c1d10adb	362	#endif
9fb9cbb1 YK	363	.me = THIS_MODULE,
	364	};
	365
32292a7f PM	366	MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6));
	367	MODULE_LICENSE("GPL");
	368	MODULE_AUTHOR("Yasuyuki KOZAKAI @USAGI <yasuyuki.kozakai@toshiba.co.jp>");
	369
	370	static int __init nf_conntrack_l3proto_ipv6_init(void)
9fb9cbb1 YK	371	{
	372	int ret = 0;
	373
32292a7f	374	need_conntrack();
9fb9cbb1 YK	375
	376	ret = nf_ct_frag6_init();
	377	if (ret < 0) {
	378	printk("nf_conntrack_ipv6: can't initialize frag6.\n");
32292a7f	379	return ret;
9fb9cbb1	380	}
605dcad6	381	ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_tcp6);
9fb9cbb1 YK	382	if (ret < 0) {
	383	printk("nf_conntrack_ipv6: can't register tcp.\n");
	384	goto cleanup_frag6;
	385	}
	386
605dcad6	387	ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_udp6);
9fb9cbb1 YK	388	if (ret < 0) {
	389	printk("nf_conntrack_ipv6: can't register udp.\n");
	390	goto cleanup_tcp;
	391	}
	392
605dcad6	393	ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_icmpv6);
9fb9cbb1 YK	394	if (ret < 0) {
	395	printk("nf_conntrack_ipv6: can't register icmpv6.\n");
	396	goto cleanup_udp;
	397	}
	398
	399	ret = nf_conntrack_l3proto_register(&nf_conntrack_l3proto_ipv6);
	400	if (ret < 0) {
	401	printk("nf_conntrack_ipv6: can't register ipv6\n");
	402	goto cleanup_icmpv6;
	403	}
	404
964ddaa1 PM	405	ret = nf_register_hooks(ipv6_conntrack_ops,
964ddaa1 PM	406	ARRAY_SIZE(ipv6_conntrack_ops));
9fb9cbb1 YK	407	if (ret < 0) {
	408	printk("nf_conntrack_ipv6: can't register pre-routing defrag "
	409	"hook.\n");
	410	goto cleanup_ipv6;
	411	}
9fb9cbb1 YK	412	return ret;
9fb9cbb1 YK	413
9fb9cbb1 YK	414	cleanup_ipv6:
	415	nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
	416	cleanup_icmpv6:
605dcad6	417	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6);
9fb9cbb1	418	cleanup_udp:
605dcad6	419	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6);
9fb9cbb1	420	cleanup_tcp:
605dcad6	421	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6);
9fb9cbb1 YK	422	cleanup_frag6:
9fb9cbb1 YK	423	nf_ct_frag6_cleanup();
9fb9cbb1 YK	424	return ret;
	425	}
	426
65b4b4e8	427	static void __exit nf_conntrack_l3proto_ipv6_fini(void)
9fb9cbb1	428	{
32292a7f	429	synchronize_net();
32292a7f PM	430	nf_unregister_hooks(ipv6_conntrack_ops, ARRAY_SIZE(ipv6_conntrack_ops));
32292a7f PM	431	nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
605dcad6 MJ	432	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6);
	433	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6);
	434	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6);
32292a7f	435	nf_ct_frag6_cleanup();
9fb9cbb1 YK	436	}
9fb9cbb1 YK	437
65b4b4e8 AM	438	module_init(nf_conntrack_l3proto_ipv6_init);
65b4b4e8 AM	439	module_exit(nf_conntrack_l3proto_ipv6_fini);