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

	ap = skb_header_pointer(skb, nhoff + offsetof(struct ipv6hdr, saddr),
				sizeof(_addrs), _addrs);
	if (ap == NULL)
		return 0;

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

	return 1;
}

static int 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 1;
}

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)));
}

static int ipv6_print_conntrack(struct seq_file *s,
				const struct nf_conn *conntrack)
{
	return 0;
}

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


	/* This is where we call the helper: as the packet goes out. */
	ct = nf_ct_get(*pskb, &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(*pskb, extoff, &pnum,
					 (*pskb)->len - extoff);
	if (protoff > (*pskb)->len || pnum == NEXTHDR_FRAGMENT) {
		pr_debug("proto header not found\n");
		return NF_ACCEPT;
	}

	ret = helper->help(pskb, 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(pskb);
}

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

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

	reasm = nf_ct_frag6_gather(*pskb);

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

	/* error occured or not fragmented */
	if (reasm == *pskb)
		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(unsigned int hooknum,
				      struct sk_buff **pskb,
				      const struct net_device *in,
				      const struct net_device *out,
				      int (*okfn)(struct sk_buff *))
{
	struct sk_buff *reasm = (*pskb)->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(PF_INET6, hooknum, &reasm);
			if (ret != NF_ACCEPT)
				return ret;
		}
		nf_conntrack_get(reasm->nfct);
		(*pskb)->nfct = reasm->nfct;
		(*pskb)->nfctinfo = reasm->nfctinfo;
		return NF_ACCEPT;
	}

	return nf_conntrack_in(PF_INET6, hooknum, pskb);
}

static unsigned int ipv6_conntrack_local(unsigned int hooknum,
					 struct sk_buff **pskb,
					 const struct net_device *in,
					 const struct net_device *out,
					 int (*okfn)(struct sk_buff *))
{
	/* root is playing with raw sockets. */
	if ((*pskb)->len < sizeof(struct ipv6hdr)) {
		if (net_ratelimit())
			printk("ipv6_conntrack_local: packet too short\n");
		return NF_ACCEPT;
	}
	return ipv6_conntrack_in(hooknum, pskb, in, out, okfn);
}

static struct nf_hook_ops ipv6_conntrack_ops[] = {
	{
		.hook		= ipv6_defrag,
		.owner		= THIS_MODULE,
		.pf		= PF_INET6,
		.hooknum	= NF_IP6_PRE_ROUTING,
		.priority	= NF_IP6_PRI_CONNTRACK_DEFRAG,
	},
	{
		.hook		= ipv6_conntrack_in,
		.owner		= THIS_MODULE,
		.pf		= PF_INET6,
		.hooknum	= NF_IP6_PRE_ROUTING,
		.priority	= NF_IP6_PRI_CONNTRACK,
	},
	{
		.hook		= ipv6_conntrack_local,
		.owner		= THIS_MODULE,
		.pf		= PF_INET6,
		.hooknum	= NF_IP6_LOCAL_OUT,
		.priority	= NF_IP6_PRI_CONNTRACK,
	},
	{
		.hook		= ipv6_defrag,
		.owner		= THIS_MODULE,
		.pf		= PF_INET6,
		.hooknum	= NF_IP6_LOCAL_OUT,
		.priority	= NF_IP6_PRI_CONNTRACK_DEFRAG,
	},
	{
		.hook		= ipv6_confirm,
		.owner		= THIS_MODULE,
		.pf		= PF_INET6,
		.hooknum	= NF_IP6_POST_ROUTING,
		.priority	= NF_IP6_PRI_LAST,
	},
	{
		.hook		= ipv6_confirm,
		.owner		= THIS_MODULE,
		.pf		= PF_INET6,
		.hooknum	= NF_IP6_LOCAL_IN,
		.priority	= NF_IP6_PRI_LAST-1,
	},
};

#ifdef CONFIG_SYSCTL
static ctl_table nf_ct_ipv6_sysctl_table[] = {
	{
		.ctl_name	= NET_NF_CONNTRACK_FRAG6_TIMEOUT,
		.procname	= "nf_conntrack_frag6_timeout",
		.data		= &nf_ct_frag6_timeout,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec_jiffies,
	},
	{
		.ctl_name	= NET_NF_CONNTRACK_FRAG6_LOW_THRESH,
		.procname	= "nf_conntrack_frag6_low_thresh",
		.data		= &nf_ct_frag6_low_thresh,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
	{
		.ctl_name	= NET_NF_CONNTRACK_FRAG6_HIGH_THRESH,
		.procname	= "nf_conntrack_frag6_high_thresh",
		.data		= &nf_ct_frag6_high_thresh,
		.maxlen		= sizeof(unsigned int),
		.mode		= 0644,
		.proc_handler	= &proc_dointvec,
	},
	{ .ctl_name = 0 }
};
#endif

#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_nfattr(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 size_t cta_min_ip[CTA_IP_MAX+1] = {
	[CTA_IP_V6_SRC]	= sizeof(u_int32_t)*4,
	[CTA_IP_V6_DST]	= sizeof(u_int32_t)*4,
};

static int ipv6_nfattr_to_tuple(struct nlattr *tb[],
				struct nf_conntrack_tuple *t)
{
	if (!tb[CTA_IP_V6_SRC] || !tb[CTA_IP_V6_DST])
		return -EINVAL;

	if (nfattr_bad_size(tb, CTA_IP_MAX, cta_min_ip))
		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,
	.print_conntrack	= ipv6_print_conntrack,
	.get_l4proto		= ipv6_get_l4proto,
#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
	.tuple_to_nfattr	= ipv6_tuple_to_nfattr,
	.nfattr_to_tuple	= ipv6_nfattr_to_tuple,
#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>
	21
	22	#include <linux/netfilter_ipv6.h>
	23	#include <net/netfilter/nf_conntrack.h>
	24	#include <net/netfilter/nf_conntrack_helper.h>
605dcad6	25	#include <net/netfilter/nf_conntrack_l4proto.h>
9fb9cbb1 YK	26	#include <net/netfilter/nf_conntrack_l3proto.h>
	27	#include <net/netfilter/nf_conntrack_core.h>
	28
9fb9cbb1 YK	29	static int ipv6_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff,
	30	struct nf_conntrack_tuple *tuple)
	31	{
	32	u_int32_t _addrs[8], *ap;
	33
	34	ap = skb_header_pointer(skb, nhoff + offsetof(struct ipv6hdr, saddr),
	35	sizeof(_addrs), _addrs);
	36	if (ap == NULL)
	37	return 0;
	38
	39	memcpy(tuple->src.u3.ip6, ap, sizeof(tuple->src.u3.ip6));
	40	memcpy(tuple->dst.u3.ip6, ap + 4, sizeof(tuple->dst.u3.ip6));
	41
	42	return 1;
	43	}
	44
	45	static int ipv6_invert_tuple(struct nf_conntrack_tuple *tuple,
	46	const struct nf_conntrack_tuple *orig)
	47	{
	48	memcpy(tuple->src.u3.ip6, orig->dst.u3.ip6, sizeof(tuple->src.u3.ip6));
	49	memcpy(tuple->dst.u3.ip6, orig->src.u3.ip6, sizeof(tuple->dst.u3.ip6));
	50
	51	return 1;
	52	}
	53
	54	static int ipv6_print_tuple(struct seq_file *s,
	55	const struct nf_conntrack_tuple *tuple)
	56	{
46b86a2d	57	return seq_printf(s, "src=" NIP6_FMT " dst=" NIP6_FMT " ",
9fb9cbb1 YK	58	NIP6(((struct in6_addr )tuple->src.u3.ip6)),
	59	NIP6(((struct in6_addr )tuple->dst.u3.ip6)));
	60	}
	61
	62	static int ipv6_print_conntrack(struct seq_file *s,
	63	const struct nf_conn *conntrack)
	64	{
	65	return 0;
	66	}
	67
	68	/*
	69	* Based on ipv6_skip_exthdr() in net/ipv6/exthdr.c
	70	*
	71	* This function parses (probably truncated) exthdr set "hdr"
	72	* of length "len". "nexthdrp" initially points to some place,
	73	* where type of the first header can be found.
	74	*
	75	* It skips all well-known exthdrs, and returns pointer to the start
	76	* of unparsable area i.e. the first header with unknown type.
	77	* if success, *nexthdr is updated by type/protocol of this header.
	78	*
	79	* NOTES: - it may return pointer pointing beyond end of packet,
	80	* if the last recognized header is truncated in the middle.
	81	* - if packet is truncated, so that all parsed headers are skipped,
	82	* it returns -1.
	83	* - if packet is fragmented, return pointer of the fragment header.
	84	* - ESP is unparsable for now and considered like
	85	* normal payload protocol.
	86	* - Note also special handling of AUTH header. Thanks to IPsec wizards.
	87	*/
	88
1a3a206f AB	89	static int nf_ct_ipv6_skip_exthdr(const struct sk_buff *skb, int start,
1a3a206f AB	90	u8 *nexthdrp, int len)
9fb9cbb1 YK	91	{
	92	u8 nexthdr = *nexthdrp;
	93
	94	while (ipv6_ext_hdr(nexthdr)) {
	95	struct ipv6_opt_hdr hdr;
	96	int hdrlen;
	97
	98	if (len < (int)sizeof(struct ipv6_opt_hdr))
	99	return -1;
	100	if (nexthdr == NEXTHDR_NONE)
	101	break;
	102	if (nexthdr == NEXTHDR_FRAGMENT)
	103	break;
	104	if (skb_copy_bits(skb, start, &hdr, sizeof(hdr)))
	105	BUG();
	106	if (nexthdr == NEXTHDR_AUTH)
	107	hdrlen = (hdr.hdrlen+2)<<2;
	108	else
	109	hdrlen = ipv6_optlen(&hdr);
	110
	111	nexthdr = hdr.nexthdr;
	112	len -= hdrlen;
	113	start += hdrlen;
	114	}
	115
	116	*nexthdrp = nexthdr;
	117	return start;
	118	}
	119
ffc30690 YK	120	static int ipv6_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
ffc30690 YK	121	unsigned int dataoff, u_int8_t protonum)
9fb9cbb1	122	{
ffc30690 YK	123	unsigned int extoff = nhoff + sizeof(struct ipv6hdr);
	124	unsigned char pnum;
	125	int protoff;
	126
	127	if (skb_copy_bits(skb, nhoff + offsetof(struct ipv6hdr, nexthdr),
	128	&pnum, sizeof(pnum)) != 0) {
	129	pr_debug("ip6_conntrack_core: can't get nexthdr\n");
	130	return -NF_ACCEPT;
	131	}
	132	protoff = nf_ct_ipv6_skip_exthdr(skb, extoff, &pnum, skb->len - extoff);
9fb9cbb1	133	/*
ffc30690	134	* (protoff == skb->len) mean that the packet doesn't have no data
9fb9cbb1 YK	135	* except of IPv6 & ext headers. but it's tracked anyway. - YK
9fb9cbb1 YK	136	*/
ffc30690	137	if ((protoff < 0) \|\| (protoff > skb->len)) {
0d53778e	138	pr_debug("ip6_conntrack_core: can't find proto in pkt\n");
9fb9cbb1 YK	139	return -NF_ACCEPT;
	140	}
	141
	142	*dataoff = protoff;
	143	*protonum = pnum;
	144	return NF_ACCEPT;
	145	}
	146
9fb9cbb1 YK	147	static unsigned int ipv6_confirm(unsigned int hooknum,
	148	struct sk_buff **pskb,
	149	const struct net_device *in,
	150	const struct net_device *out,
	151	int (okfn)(struct sk_buff ))
	152	{
	153	struct nf_conn *ct;
dc808fe2	154	struct nf_conn_help *help;
3c158f7f	155	struct nf_conntrack_helper *helper;
9fb9cbb1	156	enum ip_conntrack_info ctinfo;
dc808fe2	157	unsigned int ret, protoff;
0660e03f ACM	158	unsigned int extoff = (u8 )(ipv6_hdr(pskb) + 1) - (*pskb)->data;
0660e03f ACM	159	unsigned char pnum = ipv6_hdr(*pskb)->nexthdr;
dc808fe2	160
9fb9cbb1 YK	161
	162	/* This is where we call the helper: as the packet goes out. */
	163	ct = nf_ct_get(*pskb, &ctinfo);
6442f1cf	164	if (!ct \|\| ctinfo == IP_CT_RELATED + IP_CT_IS_REPLY)
dc808fe2 HW	165	goto out;
	166
	167	help = nfct_help(ct);
3c158f7f PM	168	if (!help)
	169	goto out;
	170	/* rcu_read_lock()ed by nf_hook_slow */
	171	helper = rcu_dereference(help->helper);
	172	if (!helper)
dc808fe2 HW	173	goto out;
	174
	175	protoff = nf_ct_ipv6_skip_exthdr(*pskb, extoff, &pnum,
	176	(*pskb)->len - extoff);
75202e76	177	if (protoff > (*pskb)->len \|\| pnum == NEXTHDR_FRAGMENT) {
0d53778e	178	pr_debug("proto header not found\n");
dc808fe2	179	return NF_ACCEPT;
9fb9cbb1 YK	180	}
9fb9cbb1 YK	181
3c158f7f	182	ret = helper->help(pskb, protoff, ct, ctinfo);
dc808fe2 HW	183	if (ret != NF_ACCEPT)
	184	return ret;
	185	out:
9fb9cbb1	186	/* We've seen it coming out the other side: confirm it */
9fb9cbb1 YK	187	return nf_conntrack_confirm(pskb);
	188	}
	189
9fb9cbb1 YK	190	static unsigned int ipv6_defrag(unsigned int hooknum,
	191	struct sk_buff **pskb,
	192	const struct net_device *in,
	193	const struct net_device *out,
	194	int (okfn)(struct sk_buff ))
	195	{
	196	struct sk_buff *reasm;
	197
	198	/* Previously seen (loopback)? */
	199	if ((*pskb)->nfct)
	200	return NF_ACCEPT;
	201
	202	reasm = nf_ct_frag6_gather(*pskb);
	203
	204	/* queued */
	205	if (reasm == NULL)
	206	return NF_STOLEN;
	207
	208	/* error occured or not fragmented */
	209	if (reasm == *pskb)
	210	return NF_ACCEPT;
	211
	212	nf_ct_frag6_output(hooknum, reasm, (struct net_device *)in,
	213	(struct net_device *)out, okfn);
	214
	215	return NF_STOLEN;
	216	}
	217
	218	static unsigned int ipv6_conntrack_in(unsigned int hooknum,
	219	struct sk_buff **pskb,
	220	const struct net_device *in,
	221	const struct net_device *out,
	222	int (okfn)(struct sk_buff ))
	223	{
	224	struct sk_buff reasm = (pskb)->nfct_reasm;
	225
	226	/* This packet is fragmented and has reassembled packet. */
	227	if (reasm) {
	228	/* Reassembled packet isn't parsed yet ? */
	229	if (!reasm->nfct) {
	230	unsigned int ret;
	231
	232	ret = nf_conntrack_in(PF_INET6, hooknum, &reasm);
	233	if (ret != NF_ACCEPT)
	234	return ret;
	235	}
	236	nf_conntrack_get(reasm->nfct);
	237	(*pskb)->nfct = reasm->nfct;
dd63006b	238	(*pskb)->nfctinfo = reasm->nfctinfo;
9fb9cbb1 YK	239	return NF_ACCEPT;
	240	}
	241
	242	return nf_conntrack_in(PF_INET6, hooknum, pskb);
	243	}
	244
	245	static unsigned int ipv6_conntrack_local(unsigned int hooknum,
	246	struct sk_buff **pskb,
	247	const struct net_device *in,
	248	const struct net_device *out,
	249	int (okfn)(struct sk_buff ))
	250	{
	251	/* root is playing with raw sockets. */
	252	if ((*pskb)->len < sizeof(struct ipv6hdr)) {
	253	if (net_ratelimit())
	254	printk("ipv6_conntrack_local: packet too short\n");
	255	return NF_ACCEPT;
	256	}
	257	return ipv6_conntrack_in(hooknum, pskb, in, out, okfn);
	258	}
	259
964ddaa1 PM	260	static struct nf_hook_ops ipv6_conntrack_ops[] = {
	261	{
	262	.hook = ipv6_defrag,
	263	.owner = THIS_MODULE,
	264	.pf = PF_INET6,
	265	.hooknum = NF_IP6_PRE_ROUTING,
	266	.priority = NF_IP6_PRI_CONNTRACK_DEFRAG,
	267	},
	268	{
	269	.hook = ipv6_conntrack_in,
	270	.owner = THIS_MODULE,
	271	.pf = PF_INET6,
	272	.hooknum = NF_IP6_PRE_ROUTING,
	273	.priority = NF_IP6_PRI_CONNTRACK,
	274	},
	275	{
	276	.hook = ipv6_conntrack_local,
	277	.owner = THIS_MODULE,
	278	.pf = PF_INET6,
	279	.hooknum = NF_IP6_LOCAL_OUT,
	280	.priority = NF_IP6_PRI_CONNTRACK,
	281	},
	282	{
	283	.hook = ipv6_defrag,
	284	.owner = THIS_MODULE,
	285	.pf = PF_INET6,
	286	.hooknum = NF_IP6_LOCAL_OUT,
	287	.priority = NF_IP6_PRI_CONNTRACK_DEFRAG,
	288	},
	289	{
	290	.hook = ipv6_confirm,
	291	.owner = THIS_MODULE,
	292	.pf = PF_INET6,
	293	.hooknum = NF_IP6_POST_ROUTING,
	294	.priority = NF_IP6_PRI_LAST,
	295	},
	296	{
	297	.hook = ipv6_confirm,
	298	.owner = THIS_MODULE,
	299	.pf = PF_INET6,
	300	.hooknum = NF_IP6_LOCAL_IN,
	301	.priority = NF_IP6_PRI_LAST-1,
	302	},
9fb9cbb1 YK	303	};
	304
	305	#ifdef CONFIG_SYSCTL
933a41e7	306	static ctl_table nf_ct_ipv6_sysctl_table[] = {
9fb9cbb1 YK	307	{
	308	.ctl_name = NET_NF_CONNTRACK_FRAG6_TIMEOUT,
	309	.procname = "nf_conntrack_frag6_timeout",
	310	.data = &nf_ct_frag6_timeout,
	311	.maxlen = sizeof(unsigned int),
	312	.mode = 0644,
	313	.proc_handler = &proc_dointvec_jiffies,
	314	},
	315	{
	316	.ctl_name = NET_NF_CONNTRACK_FRAG6_LOW_THRESH,
	317	.procname = "nf_conntrack_frag6_low_thresh",
	318	.data = &nf_ct_frag6_low_thresh,
	319	.maxlen = sizeof(unsigned int),
	320	.mode = 0644,
7686a02c	321	.proc_handler = &proc_dointvec,
9fb9cbb1 YK	322	},
	323	{
	324	.ctl_name = NET_NF_CONNTRACK_FRAG6_HIGH_THRESH,
	325	.procname = "nf_conntrack_frag6_high_thresh",
	326	.data = &nf_ct_frag6_high_thresh,
	327	.maxlen = sizeof(unsigned int),
	328	.mode = 0644,
7686a02c	329	.proc_handler = &proc_dointvec,
9fb9cbb1	330	},
1ab1457c	331	{ .ctl_name = 0 }
9fb9cbb1	332	};
9fb9cbb1 YK	333	#endif
9fb9cbb1 YK	334
e281db5c	335	#if defined(CONFIG_NF_CT_NETLINK) \|\| defined(CONFIG_NF_CT_NETLINK_MODULE)
c1d10adb PNA	336
	337	#include <linux/netfilter/nfnetlink.h>
	338	#include <linux/netfilter/nfnetlink_conntrack.h>
	339
	340	static int ipv6_tuple_to_nfattr(struct sk_buff *skb,
	341	const struct nf_conntrack_tuple *tuple)
	342	{
df6fb868	343	NLA_PUT(skb, CTA_IP_V6_SRC, sizeof(u_int32_t) * 4,
c1d10adb	344	&tuple->src.u3.ip6);
df6fb868	345	NLA_PUT(skb, CTA_IP_V6_DST, sizeof(u_int32_t) * 4,
c1d10adb PNA	346	&tuple->dst.u3.ip6);
	347	return 0;
	348
df6fb868	349	nla_put_failure:
c1d10adb PNA	350	return -1;
	351	}
	352
df6fb868 PM	353	static const size_t cta_min_ip[CTA_IP_MAX+1] = {
	354	[CTA_IP_V6_SRC] = sizeof(u_int32_t)*4,
	355	[CTA_IP_V6_DST] = sizeof(u_int32_t)*4,
c1d10adb PNA	356	};
c1d10adb PNA	357
df6fb868	358	static int ipv6_nfattr_to_tuple(struct nlattr *tb[],
c1d10adb PNA	359	struct nf_conntrack_tuple *t)
c1d10adb PNA	360	{
df6fb868	361	if (!tb[CTA_IP_V6_SRC] \|\| !tb[CTA_IP_V6_DST])
c1d10adb PNA	362	return -EINVAL;
	363
	364	if (nfattr_bad_size(tb, CTA_IP_MAX, cta_min_ip))
	365	return -EINVAL;
	366
df6fb868	367	memcpy(&t->src.u3.ip6, nla_data(tb[CTA_IP_V6_SRC]),
c1d10adb	368	sizeof(u_int32_t) * 4);
df6fb868	369	memcpy(&t->dst.u3.ip6, nla_data(tb[CTA_IP_V6_DST]),
c1d10adb PNA	370	sizeof(u_int32_t) * 4);
	371
	372	return 0;
	373	}
	374	#endif
	375
61075af5	376	struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 __read_mostly = {
9fb9cbb1 YK	377	.l3proto = PF_INET6,
	378	.name = "ipv6",
	379	.pkt_to_tuple = ipv6_pkt_to_tuple,
	380	.invert_tuple = ipv6_invert_tuple,
	381	.print_tuple = ipv6_print_tuple,
	382	.print_conntrack = ipv6_print_conntrack,
ffc30690	383	.get_l4proto = ipv6_get_l4proto,
e281db5c	384	#if defined(CONFIG_NF_CT_NETLINK) \|\| defined(CONFIG_NF_CT_NETLINK_MODULE)
c1d10adb PNA	385	.tuple_to_nfattr = ipv6_tuple_to_nfattr,
c1d10adb PNA	386	.nfattr_to_tuple = ipv6_nfattr_to_tuple,
933a41e7 PM	387	#endif
	388	#ifdef CONFIG_SYSCTL
	389	.ctl_table_path = nf_net_netfilter_sysctl_path,
	390	.ctl_table = nf_ct_ipv6_sysctl_table,
c1d10adb	391	#endif
9fb9cbb1 YK	392	.me = THIS_MODULE,
	393	};
	394
32292a7f PM	395	MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6));
	396	MODULE_LICENSE("GPL");
	397	MODULE_AUTHOR("Yasuyuki KOZAKAI @USAGI <yasuyuki.kozakai@toshiba.co.jp>");
	398
	399	static int __init nf_conntrack_l3proto_ipv6_init(void)
9fb9cbb1 YK	400	{
	401	int ret = 0;
	402
32292a7f	403	need_conntrack();
9fb9cbb1 YK	404
	405	ret = nf_ct_frag6_init();
	406	if (ret < 0) {
	407	printk("nf_conntrack_ipv6: can't initialize frag6.\n");
32292a7f	408	return ret;
9fb9cbb1	409	}
605dcad6	410	ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_tcp6);
9fb9cbb1 YK	411	if (ret < 0) {
	412	printk("nf_conntrack_ipv6: can't register tcp.\n");
	413	goto cleanup_frag6;
	414	}
	415
605dcad6	416	ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_udp6);
9fb9cbb1 YK	417	if (ret < 0) {
	418	printk("nf_conntrack_ipv6: can't register udp.\n");
	419	goto cleanup_tcp;
	420	}
	421
605dcad6	422	ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_icmpv6);
9fb9cbb1 YK	423	if (ret < 0) {
	424	printk("nf_conntrack_ipv6: can't register icmpv6.\n");
	425	goto cleanup_udp;
	426	}
	427
	428	ret = nf_conntrack_l3proto_register(&nf_conntrack_l3proto_ipv6);
	429	if (ret < 0) {
	430	printk("nf_conntrack_ipv6: can't register ipv6\n");
	431	goto cleanup_icmpv6;
	432	}
	433
964ddaa1 PM	434	ret = nf_register_hooks(ipv6_conntrack_ops,
964ddaa1 PM	435	ARRAY_SIZE(ipv6_conntrack_ops));
9fb9cbb1 YK	436	if (ret < 0) {
	437	printk("nf_conntrack_ipv6: can't register pre-routing defrag "
	438	"hook.\n");
	439	goto cleanup_ipv6;
	440	}
9fb9cbb1 YK	441	return ret;
9fb9cbb1 YK	442
9fb9cbb1 YK	443	cleanup_ipv6:
	444	nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
	445	cleanup_icmpv6:
605dcad6	446	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6);
9fb9cbb1	447	cleanup_udp:
605dcad6	448	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6);
9fb9cbb1	449	cleanup_tcp:
605dcad6	450	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6);
9fb9cbb1 YK	451	cleanup_frag6:
9fb9cbb1 YK	452	nf_ct_frag6_cleanup();
9fb9cbb1 YK	453	return ret;
	454	}
	455
65b4b4e8	456	static void __exit nf_conntrack_l3proto_ipv6_fini(void)
9fb9cbb1	457	{
32292a7f	458	synchronize_net();
32292a7f PM	459	nf_unregister_hooks(ipv6_conntrack_ops, ARRAY_SIZE(ipv6_conntrack_ops));
32292a7f PM	460	nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
605dcad6 MJ	461	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6);
	462	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6);
	463	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6);
32292a7f	464	nf_ct_frag6_cleanup();
9fb9cbb1 YK	465	}
9fb9cbb1 YK	466
65b4b4e8 AM	467	module_init(nf_conntrack_l3proto_ipv6_init);
65b4b4e8 AM	468	module_exit(nf_conntrack_l3proto_ipv6_fini);