[net-next-2.6.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_bridge.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>
#include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
#include <net/netfilter/nf_log.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=%pI6 dst=%pI6 ",
			  tuple->src.u3.ip6, 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) {
		nf_log_packet(NFPROTO_IPV6, hooknum, skb, in, out, NULL,
			      "nf_ct_%s: dropping packet", helper->name);
		return ret;
	}
out:
	/* We've seen it coming out the other side: confirm it */
	return nf_conntrack_confirm(skb);
}

static enum ip6_defrag_users nf_ct6_defrag_user(unsigned int hooknum,
						struct sk_buff *skb)
{
#ifdef CONFIG_BRIDGE_NETFILTER
	if (skb->nf_bridge &&
	    skb->nf_bridge->mask & BRNF_NF_BRIDGE_PREROUTING)
		return IP6_DEFRAG_CONNTRACK_BRIDGE_IN;
#endif
	if (hooknum == NF_INET_PRE_ROUTING)
		return IP6_DEFRAG_CONNTRACK_IN;
	else
		return IP6_DEFRAG_CONNTRACK_OUT;

}

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 && !nf_ct_is_template((struct nf_conn *)skb->nfct))
		return NF_ACCEPT;

	reasm = nf_ct_frag6_gather(skb, nf_ct6_defrag_user(hooknum, 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		= NFPROTO_IPV6,
		.hooknum	= NF_INET_PRE_ROUTING,
		.priority	= NF_IP6_PRI_CONNTRACK_DEFRAG,
	},
	{
		.hook		= ipv6_conntrack_in,
		.owner		= THIS_MODULE,
		.pf		= NFPROTO_IPV6,
		.hooknum	= NF_INET_PRE_ROUTING,
		.priority	= NF_IP6_PRI_CONNTRACK,
	},
	{
		.hook		= ipv6_conntrack_local,
		.owner		= THIS_MODULE,
		.pf		= NFPROTO_IPV6,
		.hooknum	= NF_INET_LOCAL_OUT,
		.priority	= NF_IP6_PRI_CONNTRACK,
	},
	{
		.hook		= ipv6_defrag,
		.owner		= THIS_MODULE,
		.pf		= NFPROTO_IPV6,
		.hooknum	= NF_INET_LOCAL_OUT,
		.priority	= NF_IP6_PRI_CONNTRACK_DEFRAG,
	},
	{
		.hook		= ipv6_confirm,
		.owner		= THIS_MODULE,
		.pf		= NFPROTO_IPV6,
		.hooknum	= NF_INET_POST_ROUTING,
		.priority	= NF_IP6_PRI_LAST,
	},
	{
		.hook		= ipv6_confirm,
		.owner		= THIS_MODULE,
		.pf		= NFPROTO_IPV6,
		.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;
}

static int ipv6_nlattr_tuple_size(void)
{
	return nla_policy_len(ipv6_nla_policy, CTA_IP_MAX + 1);
}
#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_tuple_size	= ipv6_nlattr_tuple_size,
	.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	22
8fa9ff68	23	#include <linux/netfilter_bridge.h>
9fb9cbb1 YK	24	#include <linux/netfilter_ipv6.h>
	25	#include <net/netfilter/nf_conntrack.h>
	26	#include <net/netfilter/nf_conntrack_helper.h>
605dcad6	27	#include <net/netfilter/nf_conntrack_l4proto.h>
9fb9cbb1 YK	28	#include <net/netfilter/nf_conntrack_l3proto.h>
9fb9cbb1 YK	29	#include <net/netfilter/nf_conntrack_core.h>
9d2493f8	30	#include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
74f7a655	31	#include <net/netfilter/nf_log.h>
9fb9cbb1	32
8ce8439a JE	33	static bool ipv6_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff,
8ce8439a JE	34	struct nf_conntrack_tuple *tuple)
9fb9cbb1	35	{
32948588 JE	36	const u_int32_t *ap;
32948588 JE	37	u_int32_t _addrs[8];
9fb9cbb1 YK	38
	39	ap = skb_header_pointer(skb, nhoff + offsetof(struct ipv6hdr, saddr),
	40	sizeof(_addrs), _addrs);
	41	if (ap == NULL)
8ce8439a	42	return false;
9fb9cbb1 YK	43
	44	memcpy(tuple->src.u3.ip6, ap, sizeof(tuple->src.u3.ip6));
	45	memcpy(tuple->dst.u3.ip6, ap + 4, sizeof(tuple->dst.u3.ip6));
	46
8ce8439a	47	return true;
9fb9cbb1 YK	48	}
9fb9cbb1 YK	49
8ce8439a JE	50	static bool ipv6_invert_tuple(struct nf_conntrack_tuple *tuple,
8ce8439a JE	51	const struct nf_conntrack_tuple *orig)
9fb9cbb1 YK	52	{
	53	memcpy(tuple->src.u3.ip6, orig->dst.u3.ip6, sizeof(tuple->src.u3.ip6));
	54	memcpy(tuple->dst.u3.ip6, orig->src.u3.ip6, sizeof(tuple->dst.u3.ip6));
	55
8ce8439a	56	return true;
9fb9cbb1 YK	57	}
	58
	59	static int ipv6_print_tuple(struct seq_file *s,
	60	const struct nf_conntrack_tuple *tuple)
	61	{
5b095d98	62	return seq_printf(s, "src=%pI6 dst=%pI6 ",
0c6ce78a	63	tuple->src.u3.ip6, tuple->dst.u3.ip6);
9fb9cbb1 YK	64	}
9fb9cbb1 YK	65
9fb9cbb1 YK	66	/*
	67	* Based on ipv6_skip_exthdr() in net/ipv6/exthdr.c
	68	*
	69	* This function parses (probably truncated) exthdr set "hdr"
	70	* of length "len". "nexthdrp" initially points to some place,
	71	* where type of the first header can be found.
	72	*
	73	* It skips all well-known exthdrs, and returns pointer to the start
	74	* of unparsable area i.e. the first header with unknown type.
	75	* if success, *nexthdr is updated by type/protocol of this header.
	76	*
	77	* NOTES: - it may return pointer pointing beyond end of packet,
	78	* if the last recognized header is truncated in the middle.
	79	* - if packet is truncated, so that all parsed headers are skipped,
	80	* it returns -1.
	81	* - if packet is fragmented, return pointer of the fragment header.
	82	* - ESP is unparsable for now and considered like
	83	* normal payload protocol.
	84	* - Note also special handling of AUTH header. Thanks to IPsec wizards.
	85	*/
	86
1a3a206f AB	87	static int nf_ct_ipv6_skip_exthdr(const struct sk_buff *skb, int start,
1a3a206f AB	88	u8 *nexthdrp, int len)
9fb9cbb1 YK	89	{
	90	u8 nexthdr = *nexthdrp;
	91
	92	while (ipv6_ext_hdr(nexthdr)) {
	93	struct ipv6_opt_hdr hdr;
	94	int hdrlen;
	95
	96	if (len < (int)sizeof(struct ipv6_opt_hdr))
	97	return -1;
	98	if (nexthdr == NEXTHDR_NONE)
	99	break;
	100	if (nexthdr == NEXTHDR_FRAGMENT)
	101	break;
	102	if (skb_copy_bits(skb, start, &hdr, sizeof(hdr)))
	103	BUG();
	104	if (nexthdr == NEXTHDR_AUTH)
	105	hdrlen = (hdr.hdrlen+2)<<2;
	106	else
	107	hdrlen = ipv6_optlen(&hdr);
	108
	109	nexthdr = hdr.nexthdr;
	110	len -= hdrlen;
	111	start += hdrlen;
	112	}
	113
	114	*nexthdrp = nexthdr;
	115	return start;
	116	}
	117
ffc30690 YK	118	static int ipv6_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
ffc30690 YK	119	unsigned int dataoff, u_int8_t protonum)
9fb9cbb1	120	{
ffc30690 YK	121	unsigned int extoff = nhoff + sizeof(struct ipv6hdr);
	122	unsigned char pnum;
	123	int protoff;
	124
	125	if (skb_copy_bits(skb, nhoff + offsetof(struct ipv6hdr, nexthdr),
	126	&pnum, sizeof(pnum)) != 0) {
	127	pr_debug("ip6_conntrack_core: can't get nexthdr\n");
	128	return -NF_ACCEPT;
	129	}
	130	protoff = nf_ct_ipv6_skip_exthdr(skb, extoff, &pnum, skb->len - extoff);
9fb9cbb1	131	/*
ffc30690	132	* (protoff == skb->len) mean that the packet doesn't have no data
9fb9cbb1 YK	133	* except of IPv6 & ext headers. but it's tracked anyway. - YK
9fb9cbb1 YK	134	*/
ffc30690	135	if ((protoff < 0) \|\| (protoff > skb->len)) {
0d53778e	136	pr_debug("ip6_conntrack_core: can't find proto in pkt\n");
9fb9cbb1 YK	137	return -NF_ACCEPT;
	138	}
	139
	140	*dataoff = protoff;
	141	*protonum = pnum;
	142	return NF_ACCEPT;
	143	}
	144
9fb9cbb1	145	static unsigned int ipv6_confirm(unsigned int hooknum,
3db05fea	146	struct sk_buff *skb,
9fb9cbb1 YK	147	const struct net_device *in,
	148	const struct net_device *out,
	149	int (okfn)(struct sk_buff ))
	150	{
	151	struct nf_conn *ct;
32948588 JE	152	const struct nf_conn_help *help;
32948588 JE	153	const struct nf_conntrack_helper *helper;
9fb9cbb1	154	enum ip_conntrack_info ctinfo;
dc808fe2	155	unsigned int ret, protoff;
3db05fea HX	156	unsigned int extoff = (u8 *)(ipv6_hdr(skb) + 1) - skb->data;
3db05fea HX	157	unsigned char pnum = ipv6_hdr(skb)->nexthdr;
dc808fe2	158
9fb9cbb1 YK	159
9fb9cbb1 YK	160	/* This is where we call the helper: as the packet goes out. */
3db05fea	161	ct = nf_ct_get(skb, &ctinfo);
6442f1cf	162	if (!ct \|\| ctinfo == IP_CT_RELATED + IP_CT_IS_REPLY)
dc808fe2 HW	163	goto out;
	164
	165	help = nfct_help(ct);
3c158f7f PM	166	if (!help)
	167	goto out;
	168	/* rcu_read_lock()ed by nf_hook_slow */
	169	helper = rcu_dereference(help->helper);
	170	if (!helper)
dc808fe2 HW	171	goto out;
dc808fe2 HW	172
3db05fea HX	173	protoff = nf_ct_ipv6_skip_exthdr(skb, extoff, &pnum,
	174	skb->len - extoff);
	175	if (protoff > skb->len \|\| pnum == NEXTHDR_FRAGMENT) {
0d53778e	176	pr_debug("proto header not found\n");
dc808fe2	177	return NF_ACCEPT;
9fb9cbb1 YK	178	}
9fb9cbb1 YK	179
3db05fea	180	ret = helper->help(skb, protoff, ct, ctinfo);
74f7a655 PM	181	if (ret != NF_ACCEPT) {
	182	nf_log_packet(NFPROTO_IPV6, hooknum, skb, in, out, NULL,
	183	"nf_ct_%s: dropping packet", helper->name);
dc808fe2	184	return ret;
74f7a655	185	}
dc808fe2	186	out:
9fb9cbb1	187	/* We've seen it coming out the other side: confirm it */
3db05fea	188	return nf_conntrack_confirm(skb);
9fb9cbb1 YK	189	}
9fb9cbb1 YK	190
0b5ccb2e PM	191	static enum ip6_defrag_users nf_ct6_defrag_user(unsigned int hooknum,
	192	struct sk_buff *skb)
	193	{
8fa9ff68 PM	194	#ifdef CONFIG_BRIDGE_NETFILTER
	195	if (skb->nf_bridge &&
	196	skb->nf_bridge->mask & BRNF_NF_BRIDGE_PREROUTING)
	197	return IP6_DEFRAG_CONNTRACK_BRIDGE_IN;
	198	#endif
0b5ccb2e PM	199	if (hooknum == NF_INET_PRE_ROUTING)
	200	return IP6_DEFRAG_CONNTRACK_IN;
	201	else
	202	return IP6_DEFRAG_CONNTRACK_OUT;
	203
	204	}
	205
9fb9cbb1	206	static unsigned int ipv6_defrag(unsigned int hooknum,
3db05fea	207	struct sk_buff *skb,
9fb9cbb1 YK	208	const struct net_device *in,
	209	const struct net_device *out,
	210	int (okfn)(struct sk_buff ))
	211	{
	212	struct sk_buff *reasm;
	213
	214	/* Previously seen (loopback)? */
b2a15a60	215	if (skb->nfct && !nf_ct_is_template((struct nf_conn *)skb->nfct))
9fb9cbb1 YK	216	return NF_ACCEPT;
9fb9cbb1 YK	217
0b5ccb2e	218	reasm = nf_ct_frag6_gather(skb, nf_ct6_defrag_user(hooknum, skb));
9fb9cbb1 YK	219	/* queued */
	220	if (reasm == NULL)
	221	return NF_STOLEN;
	222
	223	/* error occured or not fragmented */
3db05fea	224	if (reasm == skb)
9fb9cbb1 YK	225	return NF_ACCEPT;
	226
	227	nf_ct_frag6_output(hooknum, reasm, (struct net_device *)in,
	228	(struct net_device *)out, okfn);
	229
	230	return NF_STOLEN;
	231	}
	232
a702a65f AD	233	static unsigned int __ipv6_conntrack_in(struct net *net,
	234	unsigned int hooknum,
	235	struct sk_buff *skb,
	236	int (okfn)(struct sk_buff ))
9fb9cbb1	237	{
3db05fea	238	struct sk_buff *reasm = skb->nfct_reasm;
9fb9cbb1 YK	239
	240	/* This packet is fragmented and has reassembled packet. */
	241	if (reasm) {
	242	/* Reassembled packet isn't parsed yet ? */
	243	if (!reasm->nfct) {
	244	unsigned int ret;
	245
a702a65f	246	ret = nf_conntrack_in(net, PF_INET6, hooknum, reasm);
9fb9cbb1 YK	247	if (ret != NF_ACCEPT)
	248	return ret;
	249	}
	250	nf_conntrack_get(reasm->nfct);
3db05fea HX	251	skb->nfct = reasm->nfct;
3db05fea HX	252	skb->nfctinfo = reasm->nfctinfo;
9fb9cbb1 YK	253	return NF_ACCEPT;
	254	}
	255
a702a65f AD	256	return nf_conntrack_in(net, PF_INET6, hooknum, skb);
	257	}
	258
	259	static unsigned int ipv6_conntrack_in(unsigned int hooknum,
	260	struct sk_buff *skb,
	261	const struct net_device *in,
	262	const struct net_device *out,
	263	int (okfn)(struct sk_buff ))
	264	{
	265	return __ipv6_conntrack_in(dev_net(in), hooknum, skb, okfn);
9fb9cbb1 YK	266	}
	267
	268	static unsigned int ipv6_conntrack_local(unsigned int hooknum,
3db05fea	269	struct sk_buff *skb,
9fb9cbb1 YK	270	const struct net_device *in,
	271	const struct net_device *out,
	272	int (okfn)(struct sk_buff ))
	273	{
	274	/* root is playing with raw sockets. */
3db05fea	275	if (skb->len < sizeof(struct ipv6hdr)) {
9fb9cbb1 YK	276	if (net_ratelimit())
	277	printk("ipv6_conntrack_local: packet too short\n");
	278	return NF_ACCEPT;
	279	}
a702a65f	280	return __ipv6_conntrack_in(dev_net(out), hooknum, skb, okfn);
9fb9cbb1 YK	281	}
9fb9cbb1 YK	282
1999414a	283	static struct nf_hook_ops ipv6_conntrack_ops[] __read_mostly = {
964ddaa1 PM	284	{
	285	.hook = ipv6_defrag,
	286	.owner = THIS_MODULE,
57750a22	287	.pf = NFPROTO_IPV6,
6e23ae2a	288	.hooknum = NF_INET_PRE_ROUTING,
964ddaa1 PM	289	.priority = NF_IP6_PRI_CONNTRACK_DEFRAG,
	290	},
	291	{
	292	.hook = ipv6_conntrack_in,
	293	.owner = THIS_MODULE,
57750a22	294	.pf = NFPROTO_IPV6,
6e23ae2a	295	.hooknum = NF_INET_PRE_ROUTING,
964ddaa1 PM	296	.priority = NF_IP6_PRI_CONNTRACK,
	297	},
	298	{
	299	.hook = ipv6_conntrack_local,
	300	.owner = THIS_MODULE,
57750a22	301	.pf = NFPROTO_IPV6,
6e23ae2a	302	.hooknum = NF_INET_LOCAL_OUT,
964ddaa1 PM	303	.priority = NF_IP6_PRI_CONNTRACK,
	304	},
	305	{
	306	.hook = ipv6_defrag,
	307	.owner = THIS_MODULE,
57750a22	308	.pf = NFPROTO_IPV6,
6e23ae2a	309	.hooknum = NF_INET_LOCAL_OUT,
964ddaa1 PM	310	.priority = NF_IP6_PRI_CONNTRACK_DEFRAG,
	311	},
	312	{
	313	.hook = ipv6_confirm,
	314	.owner = THIS_MODULE,
57750a22	315	.pf = NFPROTO_IPV6,
6e23ae2a	316	.hooknum = NF_INET_POST_ROUTING,
964ddaa1 PM	317	.priority = NF_IP6_PRI_LAST,
	318	},
	319	{
	320	.hook = ipv6_confirm,
	321	.owner = THIS_MODULE,
57750a22	322	.pf = NFPROTO_IPV6,
6e23ae2a	323	.hooknum = NF_INET_LOCAL_IN,
964ddaa1 PM	324	.priority = NF_IP6_PRI_LAST-1,
964ddaa1 PM	325	},
9fb9cbb1 YK	326	};
9fb9cbb1 YK	327
e281db5c	328	#if defined(CONFIG_NF_CT_NETLINK) \|\| defined(CONFIG_NF_CT_NETLINK_MODULE)
c1d10adb PNA	329
	330	#include <linux/netfilter/nfnetlink.h>
	331	#include <linux/netfilter/nfnetlink_conntrack.h>
	332
fdf70832	333	static int ipv6_tuple_to_nlattr(struct sk_buff *skb,
c1d10adb PNA	334	const struct nf_conntrack_tuple *tuple)
c1d10adb PNA	335	{
df6fb868	336	NLA_PUT(skb, CTA_IP_V6_SRC, sizeof(u_int32_t) * 4,
c1d10adb	337	&tuple->src.u3.ip6);
df6fb868	338	NLA_PUT(skb, CTA_IP_V6_DST, sizeof(u_int32_t) * 4,
c1d10adb PNA	339	&tuple->dst.u3.ip6);
	340	return 0;
	341
df6fb868	342	nla_put_failure:
c1d10adb PNA	343	return -1;
	344	}
	345
f73e924c PM	346	static const struct nla_policy ipv6_nla_policy[CTA_IP_MAX+1] = {
	347	[CTA_IP_V6_SRC] = { .len = sizeof(u_int32_t)*4 },
	348	[CTA_IP_V6_DST] = { .len = sizeof(u_int32_t)*4 },
c1d10adb PNA	349	};
c1d10adb PNA	350
fdf70832	351	static int ipv6_nlattr_to_tuple(struct nlattr *tb[],
c1d10adb PNA	352	struct nf_conntrack_tuple *t)
c1d10adb PNA	353	{
df6fb868	354	if (!tb[CTA_IP_V6_SRC] \|\| !tb[CTA_IP_V6_DST])
c1d10adb PNA	355	return -EINVAL;
c1d10adb PNA	356
df6fb868	357	memcpy(&t->src.u3.ip6, nla_data(tb[CTA_IP_V6_SRC]),
c1d10adb	358	sizeof(u_int32_t) * 4);
df6fb868	359	memcpy(&t->dst.u3.ip6, nla_data(tb[CTA_IP_V6_DST]),
c1d10adb PNA	360	sizeof(u_int32_t) * 4);
	361
	362	return 0;
	363	}
a400c30e HE	364
	365	static int ipv6_nlattr_tuple_size(void)
	366	{
	367	return nla_policy_len(ipv6_nla_policy, CTA_IP_MAX + 1);
	368	}
c1d10adb PNA	369	#endif
c1d10adb PNA	370
61075af5	371	struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 __read_mostly = {
9fb9cbb1 YK	372	.l3proto = PF_INET6,
	373	.name = "ipv6",
	374	.pkt_to_tuple = ipv6_pkt_to_tuple,
	375	.invert_tuple = ipv6_invert_tuple,
	376	.print_tuple = ipv6_print_tuple,
ffc30690	377	.get_l4proto = ipv6_get_l4proto,
e281db5c	378	#if defined(CONFIG_NF_CT_NETLINK) \|\| defined(CONFIG_NF_CT_NETLINK_MODULE)
fdf70832	379	.tuple_to_nlattr = ipv6_tuple_to_nlattr,
a400c30e	380	.nlattr_tuple_size = ipv6_nlattr_tuple_size,
fdf70832	381	.nlattr_to_tuple = ipv6_nlattr_to_tuple,
f73e924c	382	.nla_policy = ipv6_nla_policy,
933a41e7 PM	383	#endif
	384	#ifdef CONFIG_SYSCTL
	385	.ctl_table_path = nf_net_netfilter_sysctl_path,
	386	.ctl_table = nf_ct_ipv6_sysctl_table,
c1d10adb	387	#endif
9fb9cbb1 YK	388	.me = THIS_MODULE,
	389	};
	390
32292a7f PM	391	MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6));
	392	MODULE_LICENSE("GPL");
	393	MODULE_AUTHOR("Yasuyuki KOZAKAI @USAGI <yasuyuki.kozakai@toshiba.co.jp>");
	394
	395	static int __init nf_conntrack_l3proto_ipv6_init(void)
9fb9cbb1 YK	396	{
	397	int ret = 0;
	398
32292a7f	399	need_conntrack();
9fb9cbb1 YK	400
	401	ret = nf_ct_frag6_init();
	402	if (ret < 0) {
	403	printk("nf_conntrack_ipv6: can't initialize frag6.\n");
32292a7f	404	return ret;
9fb9cbb1	405	}
605dcad6	406	ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_tcp6);
9fb9cbb1 YK	407	if (ret < 0) {
	408	printk("nf_conntrack_ipv6: can't register tcp.\n");
	409	goto cleanup_frag6;
	410	}
	411
605dcad6	412	ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_udp6);
9fb9cbb1 YK	413	if (ret < 0) {
	414	printk("nf_conntrack_ipv6: can't register udp.\n");
	415	goto cleanup_tcp;
	416	}
	417
605dcad6	418	ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_icmpv6);
9fb9cbb1 YK	419	if (ret < 0) {
	420	printk("nf_conntrack_ipv6: can't register icmpv6.\n");
	421	goto cleanup_udp;
	422	}
	423
	424	ret = nf_conntrack_l3proto_register(&nf_conntrack_l3proto_ipv6);
	425	if (ret < 0) {
	426	printk("nf_conntrack_ipv6: can't register ipv6\n");
	427	goto cleanup_icmpv6;
	428	}
	429
964ddaa1 PM	430	ret = nf_register_hooks(ipv6_conntrack_ops,
964ddaa1 PM	431	ARRAY_SIZE(ipv6_conntrack_ops));
9fb9cbb1 YK	432	if (ret < 0) {
	433	printk("nf_conntrack_ipv6: can't register pre-routing defrag "
	434	"hook.\n");
	435	goto cleanup_ipv6;
	436	}
9fb9cbb1 YK	437	return ret;
9fb9cbb1 YK	438
9fb9cbb1 YK	439	cleanup_ipv6:
	440	nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
	441	cleanup_icmpv6:
605dcad6	442	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6);
9fb9cbb1	443	cleanup_udp:
605dcad6	444	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6);
9fb9cbb1	445	cleanup_tcp:
605dcad6	446	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6);
9fb9cbb1 YK	447	cleanup_frag6:
9fb9cbb1 YK	448	nf_ct_frag6_cleanup();
9fb9cbb1 YK	449	return ret;
	450	}
	451
65b4b4e8	452	static void __exit nf_conntrack_l3proto_ipv6_fini(void)
9fb9cbb1	453	{
32292a7f	454	synchronize_net();
32292a7f PM	455	nf_unregister_hooks(ipv6_conntrack_ops, ARRAY_SIZE(ipv6_conntrack_ops));
32292a7f PM	456	nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
605dcad6 MJ	457	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6);
	458	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6);
	459	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6);
32292a7f	460	nf_ct_frag6_cleanup();
9fb9cbb1 YK	461	}
9fb9cbb1 YK	462
65b4b4e8 AM	463	module_init(nf_conntrack_l3proto_ipv6_init);
65b4b4e8 AM	464	module_exit(nf_conntrack_l3proto_ipv6_fini);