[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/nf_conntrack_zones.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)
{
	u16 zone = NF_CT_DEFAULT_ZONE;

	if (skb->nfct)
		zone = nf_ct_zone((struct nf_conn *)skb->nfct);

#ifdef CONFIG_BRIDGE_NETFILTER
	if (skb->nf_bridge &&
	    skb->nf_bridge->mask & BRNF_NF_BRIDGE_PREROUTING)
		return IP6_DEFRAG_CONNTRACK_BRIDGE_IN + zone;
#endif
	if (hooknum == NF_INET_PRE_ROUTING)
		return IP6_DEFRAG_CONNTRACK_IN + zone;
	else
		return IP6_DEFRAG_CONNTRACK_OUT + zone;

}

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>
5d0aa2cc	30	#include <net/netfilter/nf_conntrack_zones.h>
9d2493f8	31	#include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
74f7a655	32	#include <net/netfilter/nf_log.h>
9fb9cbb1	33
8ce8439a JE	34	static bool ipv6_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff,
8ce8439a JE	35	struct nf_conntrack_tuple *tuple)
9fb9cbb1	36	{
32948588 JE	37	const u_int32_t *ap;
32948588 JE	38	u_int32_t _addrs[8];
9fb9cbb1 YK	39
	40	ap = skb_header_pointer(skb, nhoff + offsetof(struct ipv6hdr, saddr),
	41	sizeof(_addrs), _addrs);
	42	if (ap == NULL)
8ce8439a	43	return false;
9fb9cbb1 YK	44
	45	memcpy(tuple->src.u3.ip6, ap, sizeof(tuple->src.u3.ip6));
	46	memcpy(tuple->dst.u3.ip6, ap + 4, sizeof(tuple->dst.u3.ip6));
	47
8ce8439a	48	return true;
9fb9cbb1 YK	49	}
9fb9cbb1 YK	50
8ce8439a JE	51	static bool ipv6_invert_tuple(struct nf_conntrack_tuple *tuple,
8ce8439a JE	52	const struct nf_conntrack_tuple *orig)
9fb9cbb1 YK	53	{
	54	memcpy(tuple->src.u3.ip6, orig->dst.u3.ip6, sizeof(tuple->src.u3.ip6));
	55	memcpy(tuple->dst.u3.ip6, orig->src.u3.ip6, sizeof(tuple->dst.u3.ip6));
	56
8ce8439a	57	return true;
9fb9cbb1 YK	58	}
	59
	60	static int ipv6_print_tuple(struct seq_file *s,
	61	const struct nf_conntrack_tuple *tuple)
	62	{
5b095d98	63	return seq_printf(s, "src=%pI6 dst=%pI6 ",
0c6ce78a	64	tuple->src.u3.ip6, tuple->dst.u3.ip6);
9fb9cbb1 YK	65	}
9fb9cbb1 YK	66
9fb9cbb1 YK	67	/*
	68	* Based on ipv6_skip_exthdr() in net/ipv6/exthdr.c
	69	*
	70	* This function parses (probably truncated) exthdr set "hdr"
	71	* of length "len". "nexthdrp" initially points to some place,
	72	* where type of the first header can be found.
	73	*
	74	* It skips all well-known exthdrs, and returns pointer to the start
	75	* of unparsable area i.e. the first header with unknown type.
	76	* if success, *nexthdr is updated by type/protocol of this header.
	77	*
	78	* NOTES: - it may return pointer pointing beyond end of packet,
	79	* if the last recognized header is truncated in the middle.
	80	* - if packet is truncated, so that all parsed headers are skipped,
	81	* it returns -1.
	82	* - if packet is fragmented, return pointer of the fragment header.
	83	* - ESP is unparsable for now and considered like
	84	* normal payload protocol.
	85	* - Note also special handling of AUTH header. Thanks to IPsec wizards.
	86	*/
	87
1a3a206f AB	88	static int nf_ct_ipv6_skip_exthdr(const struct sk_buff *skb, int start,
1a3a206f AB	89	u8 *nexthdrp, int len)
9fb9cbb1 YK	90	{
	91	u8 nexthdr = *nexthdrp;
	92
	93	while (ipv6_ext_hdr(nexthdr)) {
	94	struct ipv6_opt_hdr hdr;
	95	int hdrlen;
	96
	97	if (len < (int)sizeof(struct ipv6_opt_hdr))
	98	return -1;
	99	if (nexthdr == NEXTHDR_NONE)
	100	break;
	101	if (nexthdr == NEXTHDR_FRAGMENT)
	102	break;
	103	if (skb_copy_bits(skb, start, &hdr, sizeof(hdr)))
	104	BUG();
	105	if (nexthdr == NEXTHDR_AUTH)
	106	hdrlen = (hdr.hdrlen+2)<<2;
	107	else
	108	hdrlen = ipv6_optlen(&hdr);
	109
	110	nexthdr = hdr.nexthdr;
	111	len -= hdrlen;
	112	start += hdrlen;
	113	}
	114
	115	*nexthdrp = nexthdr;
	116	return start;
	117	}
	118
ffc30690 YK	119	static int ipv6_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
ffc30690 YK	120	unsigned int dataoff, u_int8_t protonum)
9fb9cbb1	121	{
ffc30690 YK	122	unsigned int extoff = nhoff + sizeof(struct ipv6hdr);
	123	unsigned char pnum;
	124	int protoff;
	125
	126	if (skb_copy_bits(skb, nhoff + offsetof(struct ipv6hdr, nexthdr),
	127	&pnum, sizeof(pnum)) != 0) {
	128	pr_debug("ip6_conntrack_core: can't get nexthdr\n");
	129	return -NF_ACCEPT;
	130	}
	131	protoff = nf_ct_ipv6_skip_exthdr(skb, extoff, &pnum, skb->len - extoff);
9fb9cbb1	132	/*
ffc30690	133	* (protoff == skb->len) mean that the packet doesn't have no data
9fb9cbb1 YK	134	* except of IPv6 & ext headers. but it's tracked anyway. - YK
9fb9cbb1 YK	135	*/
ffc30690	136	if ((protoff < 0) \|\| (protoff > skb->len)) {
0d53778e	137	pr_debug("ip6_conntrack_core: can't find proto in pkt\n");
9fb9cbb1 YK	138	return -NF_ACCEPT;
	139	}
	140
	141	*dataoff = protoff;
	142	*protonum = pnum;
	143	return NF_ACCEPT;
	144	}
	145
9fb9cbb1	146	static unsigned int ipv6_confirm(unsigned int hooknum,
3db05fea	147	struct sk_buff *skb,
9fb9cbb1 YK	148	const struct net_device *in,
	149	const struct net_device *out,
	150	int (okfn)(struct sk_buff ))
	151	{
	152	struct nf_conn *ct;
32948588 JE	153	const struct nf_conn_help *help;
32948588 JE	154	const struct nf_conntrack_helper *helper;
9fb9cbb1	155	enum ip_conntrack_info ctinfo;
dc808fe2	156	unsigned int ret, protoff;
3db05fea HX	157	unsigned int extoff = (u8 *)(ipv6_hdr(skb) + 1) - skb->data;
3db05fea HX	158	unsigned char pnum = ipv6_hdr(skb)->nexthdr;
dc808fe2	159
9fb9cbb1 YK	160
9fb9cbb1 YK	161	/* This is where we call the helper: as the packet goes out. */
3db05fea	162	ct = nf_ct_get(skb, &ctinfo);
6442f1cf	163	if (!ct \|\| ctinfo == IP_CT_RELATED + IP_CT_IS_REPLY)
dc808fe2 HW	164	goto out;
	165
	166	help = nfct_help(ct);
3c158f7f PM	167	if (!help)
	168	goto out;
	169	/* rcu_read_lock()ed by nf_hook_slow */
	170	helper = rcu_dereference(help->helper);
	171	if (!helper)
dc808fe2 HW	172	goto out;
dc808fe2 HW	173
3db05fea HX	174	protoff = nf_ct_ipv6_skip_exthdr(skb, extoff, &pnum,
	175	skb->len - extoff);
	176	if (protoff > skb->len \|\| pnum == NEXTHDR_FRAGMENT) {
0d53778e	177	pr_debug("proto header not found\n");
dc808fe2	178	return NF_ACCEPT;
9fb9cbb1 YK	179	}
9fb9cbb1 YK	180
3db05fea	181	ret = helper->help(skb, protoff, ct, ctinfo);
74f7a655 PM	182	if (ret != NF_ACCEPT) {
	183	nf_log_packet(NFPROTO_IPV6, hooknum, skb, in, out, NULL,
	184	"nf_ct_%s: dropping packet", helper->name);
dc808fe2	185	return ret;
74f7a655	186	}
dc808fe2	187	out:
9fb9cbb1	188	/* We've seen it coming out the other side: confirm it */
3db05fea	189	return nf_conntrack_confirm(skb);
9fb9cbb1 YK	190	}
9fb9cbb1 YK	191
0b5ccb2e PM	192	static enum ip6_defrag_users nf_ct6_defrag_user(unsigned int hooknum,
	193	struct sk_buff *skb)
	194	{
5d0aa2cc PM	195	u16 zone = NF_CT_DEFAULT_ZONE;
	196
	197	if (skb->nfct)
	198	zone = nf_ct_zone((struct nf_conn *)skb->nfct);
	199
8fa9ff68 PM	200	#ifdef CONFIG_BRIDGE_NETFILTER
	201	if (skb->nf_bridge &&
	202	skb->nf_bridge->mask & BRNF_NF_BRIDGE_PREROUTING)
5d0aa2cc	203	return IP6_DEFRAG_CONNTRACK_BRIDGE_IN + zone;
8fa9ff68	204	#endif
0b5ccb2e	205	if (hooknum == NF_INET_PRE_ROUTING)
5d0aa2cc	206	return IP6_DEFRAG_CONNTRACK_IN + zone;
0b5ccb2e	207	else
5d0aa2cc	208	return IP6_DEFRAG_CONNTRACK_OUT + zone;
0b5ccb2e PM	209
	210	}
	211
9fb9cbb1	212	static unsigned int ipv6_defrag(unsigned int hooknum,
3db05fea	213	struct sk_buff *skb,
9fb9cbb1 YK	214	const struct net_device *in,
	215	const struct net_device *out,
	216	int (okfn)(struct sk_buff ))
	217	{
	218	struct sk_buff *reasm;
	219
	220	/* Previously seen (loopback)? */
b2a15a60	221	if (skb->nfct && !nf_ct_is_template((struct nf_conn *)skb->nfct))
9fb9cbb1 YK	222	return NF_ACCEPT;
9fb9cbb1 YK	223
0b5ccb2e	224	reasm = nf_ct_frag6_gather(skb, nf_ct6_defrag_user(hooknum, skb));
9fb9cbb1 YK	225	/* queued */
	226	if (reasm == NULL)
	227	return NF_STOLEN;
	228
	229	/* error occured or not fragmented */
3db05fea	230	if (reasm == skb)
9fb9cbb1 YK	231	return NF_ACCEPT;
	232
	233	nf_ct_frag6_output(hooknum, reasm, (struct net_device *)in,
	234	(struct net_device *)out, okfn);
	235
	236	return NF_STOLEN;
	237	}
	238
a702a65f AD	239	static unsigned int __ipv6_conntrack_in(struct net *net,
	240	unsigned int hooknum,
	241	struct sk_buff *skb,
	242	int (okfn)(struct sk_buff ))
9fb9cbb1	243	{
3db05fea	244	struct sk_buff *reasm = skb->nfct_reasm;
9fb9cbb1 YK	245
	246	/* This packet is fragmented and has reassembled packet. */
	247	if (reasm) {
	248	/* Reassembled packet isn't parsed yet ? */
	249	if (!reasm->nfct) {
	250	unsigned int ret;
	251
a702a65f	252	ret = nf_conntrack_in(net, PF_INET6, hooknum, reasm);
9fb9cbb1 YK	253	if (ret != NF_ACCEPT)
	254	return ret;
	255	}
	256	nf_conntrack_get(reasm->nfct);
3db05fea HX	257	skb->nfct = reasm->nfct;
3db05fea HX	258	skb->nfctinfo = reasm->nfctinfo;
9fb9cbb1 YK	259	return NF_ACCEPT;
	260	}
	261
a702a65f AD	262	return nf_conntrack_in(net, PF_INET6, hooknum, skb);
	263	}
	264
	265	static unsigned int ipv6_conntrack_in(unsigned int hooknum,
	266	struct sk_buff *skb,
	267	const struct net_device *in,
	268	const struct net_device *out,
	269	int (okfn)(struct sk_buff ))
	270	{
	271	return __ipv6_conntrack_in(dev_net(in), hooknum, skb, okfn);
9fb9cbb1 YK	272	}
	273
	274	static unsigned int ipv6_conntrack_local(unsigned int hooknum,
3db05fea	275	struct sk_buff *skb,
9fb9cbb1 YK	276	const struct net_device *in,
	277	const struct net_device *out,
	278	int (okfn)(struct sk_buff ))
	279	{
	280	/* root is playing with raw sockets. */
3db05fea	281	if (skb->len < sizeof(struct ipv6hdr)) {
9fb9cbb1 YK	282	if (net_ratelimit())
	283	printk("ipv6_conntrack_local: packet too short\n");
	284	return NF_ACCEPT;
	285	}
a702a65f	286	return __ipv6_conntrack_in(dev_net(out), hooknum, skb, okfn);
9fb9cbb1 YK	287	}
9fb9cbb1 YK	288
1999414a	289	static struct nf_hook_ops ipv6_conntrack_ops[] __read_mostly = {
964ddaa1 PM	290	{
	291	.hook = ipv6_defrag,
	292	.owner = THIS_MODULE,
57750a22	293	.pf = NFPROTO_IPV6,
6e23ae2a	294	.hooknum = NF_INET_PRE_ROUTING,
964ddaa1 PM	295	.priority = NF_IP6_PRI_CONNTRACK_DEFRAG,
	296	},
	297	{
	298	.hook = ipv6_conntrack_in,
	299	.owner = THIS_MODULE,
57750a22	300	.pf = NFPROTO_IPV6,
6e23ae2a	301	.hooknum = NF_INET_PRE_ROUTING,
964ddaa1 PM	302	.priority = NF_IP6_PRI_CONNTRACK,
	303	},
	304	{
	305	.hook = ipv6_conntrack_local,
	306	.owner = THIS_MODULE,
57750a22	307	.pf = NFPROTO_IPV6,
6e23ae2a	308	.hooknum = NF_INET_LOCAL_OUT,
964ddaa1 PM	309	.priority = NF_IP6_PRI_CONNTRACK,
	310	},
	311	{
	312	.hook = ipv6_defrag,
	313	.owner = THIS_MODULE,
57750a22	314	.pf = NFPROTO_IPV6,
6e23ae2a	315	.hooknum = NF_INET_LOCAL_OUT,
964ddaa1 PM	316	.priority = NF_IP6_PRI_CONNTRACK_DEFRAG,
	317	},
	318	{
	319	.hook = ipv6_confirm,
	320	.owner = THIS_MODULE,
57750a22	321	.pf = NFPROTO_IPV6,
6e23ae2a	322	.hooknum = NF_INET_POST_ROUTING,
964ddaa1 PM	323	.priority = NF_IP6_PRI_LAST,
	324	},
	325	{
	326	.hook = ipv6_confirm,
	327	.owner = THIS_MODULE,
57750a22	328	.pf = NFPROTO_IPV6,
6e23ae2a	329	.hooknum = NF_INET_LOCAL_IN,
964ddaa1 PM	330	.priority = NF_IP6_PRI_LAST-1,
964ddaa1 PM	331	},
9fb9cbb1 YK	332	};
9fb9cbb1 YK	333
e281db5c	334	#if defined(CONFIG_NF_CT_NETLINK) \|\| defined(CONFIG_NF_CT_NETLINK_MODULE)
c1d10adb PNA	335
	336	#include <linux/netfilter/nfnetlink.h>
	337	#include <linux/netfilter/nfnetlink_conntrack.h>
	338
fdf70832	339	static int ipv6_tuple_to_nlattr(struct sk_buff *skb,
c1d10adb PNA	340	const struct nf_conntrack_tuple *tuple)
c1d10adb PNA	341	{
df6fb868	342	NLA_PUT(skb, CTA_IP_V6_SRC, sizeof(u_int32_t) * 4,
c1d10adb	343	&tuple->src.u3.ip6);
df6fb868	344	NLA_PUT(skb, CTA_IP_V6_DST, sizeof(u_int32_t) * 4,
c1d10adb PNA	345	&tuple->dst.u3.ip6);
	346	return 0;
	347
df6fb868	348	nla_put_failure:
c1d10adb PNA	349	return -1;
	350	}
	351
f73e924c PM	352	static const struct nla_policy ipv6_nla_policy[CTA_IP_MAX+1] = {
	353	[CTA_IP_V6_SRC] = { .len = sizeof(u_int32_t)*4 },
	354	[CTA_IP_V6_DST] = { .len = sizeof(u_int32_t)*4 },
c1d10adb PNA	355	};
c1d10adb PNA	356
fdf70832	357	static int ipv6_nlattr_to_tuple(struct nlattr *tb[],
c1d10adb PNA	358	struct nf_conntrack_tuple *t)
c1d10adb PNA	359	{
df6fb868	360	if (!tb[CTA_IP_V6_SRC] \|\| !tb[CTA_IP_V6_DST])
c1d10adb PNA	361	return -EINVAL;
c1d10adb PNA	362
df6fb868	363	memcpy(&t->src.u3.ip6, nla_data(tb[CTA_IP_V6_SRC]),
c1d10adb	364	sizeof(u_int32_t) * 4);
df6fb868	365	memcpy(&t->dst.u3.ip6, nla_data(tb[CTA_IP_V6_DST]),
c1d10adb PNA	366	sizeof(u_int32_t) * 4);
	367
	368	return 0;
	369	}
a400c30e HE	370
	371	static int ipv6_nlattr_tuple_size(void)
	372	{
	373	return nla_policy_len(ipv6_nla_policy, CTA_IP_MAX + 1);
	374	}
c1d10adb PNA	375	#endif
c1d10adb PNA	376
61075af5	377	struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 __read_mostly = {
9fb9cbb1 YK	378	.l3proto = PF_INET6,
	379	.name = "ipv6",
	380	.pkt_to_tuple = ipv6_pkt_to_tuple,
	381	.invert_tuple = ipv6_invert_tuple,
	382	.print_tuple = ipv6_print_tuple,
ffc30690	383	.get_l4proto = ipv6_get_l4proto,
e281db5c	384	#if defined(CONFIG_NF_CT_NETLINK) \|\| defined(CONFIG_NF_CT_NETLINK_MODULE)
fdf70832	385	.tuple_to_nlattr = ipv6_tuple_to_nlattr,
a400c30e	386	.nlattr_tuple_size = ipv6_nlattr_tuple_size,
fdf70832	387	.nlattr_to_tuple = ipv6_nlattr_to_tuple,
f73e924c	388	.nla_policy = ipv6_nla_policy,
933a41e7 PM	389	#endif
	390	#ifdef CONFIG_SYSCTL
	391	.ctl_table_path = nf_net_netfilter_sysctl_path,
	392	.ctl_table = nf_ct_ipv6_sysctl_table,
c1d10adb	393	#endif
9fb9cbb1 YK	394	.me = THIS_MODULE,
	395	};
	396
32292a7f PM	397	MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6));
	398	MODULE_LICENSE("GPL");
	399	MODULE_AUTHOR("Yasuyuki KOZAKAI @USAGI <yasuyuki.kozakai@toshiba.co.jp>");
	400
	401	static int __init nf_conntrack_l3proto_ipv6_init(void)
9fb9cbb1 YK	402	{
	403	int ret = 0;
	404
32292a7f	405	need_conntrack();
9fb9cbb1 YK	406
	407	ret = nf_ct_frag6_init();
	408	if (ret < 0) {
	409	printk("nf_conntrack_ipv6: can't initialize frag6.\n");
32292a7f	410	return ret;
9fb9cbb1	411	}
605dcad6	412	ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_tcp6);
9fb9cbb1 YK	413	if (ret < 0) {
	414	printk("nf_conntrack_ipv6: can't register tcp.\n");
	415	goto cleanup_frag6;
	416	}
	417
605dcad6	418	ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_udp6);
9fb9cbb1 YK	419	if (ret < 0) {
	420	printk("nf_conntrack_ipv6: can't register udp.\n");
	421	goto cleanup_tcp;
	422	}
	423
605dcad6	424	ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_icmpv6);
9fb9cbb1 YK	425	if (ret < 0) {
	426	printk("nf_conntrack_ipv6: can't register icmpv6.\n");
	427	goto cleanup_udp;
	428	}
	429
	430	ret = nf_conntrack_l3proto_register(&nf_conntrack_l3proto_ipv6);
	431	if (ret < 0) {
	432	printk("nf_conntrack_ipv6: can't register ipv6\n");
	433	goto cleanup_icmpv6;
	434	}
	435
964ddaa1 PM	436	ret = nf_register_hooks(ipv6_conntrack_ops,
964ddaa1 PM	437	ARRAY_SIZE(ipv6_conntrack_ops));
9fb9cbb1 YK	438	if (ret < 0) {
	439	printk("nf_conntrack_ipv6: can't register pre-routing defrag "
	440	"hook.\n");
	441	goto cleanup_ipv6;
	442	}
9fb9cbb1 YK	443	return ret;
9fb9cbb1 YK	444
9fb9cbb1 YK	445	cleanup_ipv6:
	446	nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
	447	cleanup_icmpv6:
605dcad6	448	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6);
9fb9cbb1	449	cleanup_udp:
605dcad6	450	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6);
9fb9cbb1	451	cleanup_tcp:
605dcad6	452	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6);
9fb9cbb1 YK	453	cleanup_frag6:
9fb9cbb1 YK	454	nf_ct_frag6_cleanup();
9fb9cbb1 YK	455	return ret;
	456	}
	457
65b4b4e8	458	static void __exit nf_conntrack_l3proto_ipv6_fini(void)
9fb9cbb1	459	{
32292a7f	460	synchronize_net();
32292a7f PM	461	nf_unregister_hooks(ipv6_conntrack_ops, ARRAY_SIZE(ipv6_conntrack_ops));
32292a7f PM	462	nf_conntrack_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
605dcad6 MJ	463	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_icmpv6);
	464	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_udp6);
	465	nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_tcp6);
32292a7f	466	nf_ct_frag6_cleanup();
9fb9cbb1 YK	467	}
9fb9cbb1 YK	468
65b4b4e8 AM	469	module_init(nf_conntrack_l3proto_ipv6_init);
65b4b4e8 AM	470	module_exit(nf_conntrack_l3proto_ipv6_fini);