[net-next-2.6.git] / net / ipv6 / mip6.c

/*
 * Copyright (C)2003-2006 Helsinki University of Technology
 * Copyright (C)2003-2006 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 as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
/*
 * Authors:
 *	Noriaki TAKAMIYA @USAGI
 *	Masahide NAKAMURA @USAGI
 */

#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/time.h>
#include <linux/ipv6.h>
#include <linux/icmpv6.h>
#include <net/sock.h>
#include <net/ipv6.h>
#include <net/ip6_checksum.h>
#include <net/rawv6.h>
#include <net/xfrm.h>
#include <net/mip6.h>

static inline unsigned int calc_padlen(unsigned int len, unsigned int n)
{
	return (n - len + 16) & 0x7;
}

static inline void *mip6_padn(__u8 *data, __u8 padlen)
{
	if (!data)
		return NULL;
	if (padlen == 1) {
		data[0] = MIP6_OPT_PAD_1;
	} else if (padlen > 1) {
		data[0] = MIP6_OPT_PAD_N;
		data[1] = padlen - 2;
		if (padlen > 2)
			memset(data+2, 0, data[1]);
	}
	return data + padlen;
}

static inline void mip6_param_prob(struct sk_buff *skb, int code, int pos)
{
	icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos, skb->dev);
}

static int mip6_mh_len(int type)
{
	int len = 0;

	switch (type) {
	case IP6_MH_TYPE_BRR:
		len = 0;
		break;
	case IP6_MH_TYPE_HOTI:
	case IP6_MH_TYPE_COTI:
	case IP6_MH_TYPE_BU:
	case IP6_MH_TYPE_BACK:
		len = 1;
		break;
	case IP6_MH_TYPE_HOT:
	case IP6_MH_TYPE_COT:
	case IP6_MH_TYPE_BERROR:
		len = 2;
		break;
	}
	return len;
}

static int mip6_mh_filter(struct sock *sk, struct sk_buff *skb)
{
	struct ip6_mh *mh;

	if (!pskb_may_pull(skb, (skb_transport_offset(skb)) + 8) ||
	    !pskb_may_pull(skb, (skb_transport_offset(skb) +
				 ((skb_transport_header(skb)[1] + 1) << 3))))
		return -1;

	mh = (struct ip6_mh *)skb_transport_header(skb);

	if (mh->ip6mh_hdrlen < mip6_mh_len(mh->ip6mh_type)) {
		LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH message too short: %d vs >=%d\n",
			       mh->ip6mh_hdrlen, mip6_mh_len(mh->ip6mh_type));
		mip6_param_prob(skb, 0, ((&mh->ip6mh_hdrlen) -
					 skb_network_header(skb)));
		return -1;
	}

	if (mh->ip6mh_proto != IPPROTO_NONE) {
		LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH invalid payload proto = %d\n",
			       mh->ip6mh_proto);
		mip6_param_prob(skb, 0, ((&mh->ip6mh_proto) -
					 skb_network_header(skb)));
		return -1;
	}

	return 0;
}

struct mip6_report_rate_limiter {
	spinlock_t lock;
	struct timeval stamp;
	int iif;
	struct in6_addr src;
	struct in6_addr dst;
};

static struct mip6_report_rate_limiter mip6_report_rl = {
	.lock = __SPIN_LOCK_UNLOCKED(mip6_report_rl.lock)
};

static int mip6_destopt_input(struct xfrm_state *x, struct sk_buff *skb)
{
	struct ipv6hdr *iph = ipv6_hdr(skb);
	struct ipv6_destopt_hdr *destopt = (struct ipv6_destopt_hdr *)skb->data;
	int err = destopt->nexthdr;

	spin_lock(&x->lock);
	if (!ipv6_addr_equal(&iph->saddr, (struct in6_addr *)x->coaddr) &&
	    !ipv6_addr_any((struct in6_addr *)x->coaddr))
		err = -ENOENT;
	spin_unlock(&x->lock);

	return err;
}

/* Destination Option Header is inserted.
 * IP Header's src address is replaced with Home Address Option in
 * Destination Option Header.
 */
static int mip6_destopt_output(struct xfrm_state *x, struct sk_buff *skb)
{
	struct ipv6hdr *iph;
	struct ipv6_destopt_hdr *dstopt;
	struct ipv6_destopt_hao *hao;
	u8 nexthdr;
	int len;

	skb_push(skb, -skb_network_offset(skb));
	iph = ipv6_hdr(skb);

	nexthdr = *skb_mac_header(skb);
	*skb_mac_header(skb) = IPPROTO_DSTOPTS;

	dstopt = (struct ipv6_destopt_hdr *)skb_transport_header(skb);
	dstopt->nexthdr = nexthdr;

	hao = mip6_padn((char *)(dstopt + 1),
			calc_padlen(sizeof(*dstopt), 6));

	hao->type = IPV6_TLV_HAO;
	hao->length = sizeof(*hao) - 2;
	BUG_TRAP(hao->length == 16);

	len = ((char *)hao - (char *)dstopt) + sizeof(*hao);

	memcpy(&hao->addr, &iph->saddr, sizeof(hao->addr));
	spin_lock_bh(&x->lock);
	memcpy(&iph->saddr, x->coaddr, sizeof(iph->saddr));
	spin_unlock_bh(&x->lock);

	BUG_TRAP(len == x->props.header_len);
	dstopt->hdrlen = (x->props.header_len >> 3) - 1;

	return 0;
}

static inline int mip6_report_rl_allow(struct timeval *stamp,
				       struct in6_addr *dst,
				       struct in6_addr *src, int iif)
{
	int allow = 0;

	spin_lock_bh(&mip6_report_rl.lock);
	if (mip6_report_rl.stamp.tv_sec != stamp->tv_sec ||
	    mip6_report_rl.stamp.tv_usec != stamp->tv_usec ||
	    mip6_report_rl.iif != iif ||
	    !ipv6_addr_equal(&mip6_report_rl.src, src) ||
	    !ipv6_addr_equal(&mip6_report_rl.dst, dst)) {
		mip6_report_rl.stamp.tv_sec = stamp->tv_sec;
		mip6_report_rl.stamp.tv_usec = stamp->tv_usec;
		mip6_report_rl.iif = iif;
		ipv6_addr_copy(&mip6_report_rl.src, src);
		ipv6_addr_copy(&mip6_report_rl.dst, dst);
		allow = 1;
	}
	spin_unlock_bh(&mip6_report_rl.lock);
	return allow;
}

static int mip6_destopt_reject(struct xfrm_state *x, struct sk_buff *skb, struct flowi *fl)
{
	struct inet6_skb_parm *opt = (struct inet6_skb_parm *)skb->cb;
	struct ipv6_destopt_hao *hao = NULL;
	struct xfrm_selector sel;
	int offset;
	struct timeval stamp;
	int err = 0;

	if (unlikely(fl->proto == IPPROTO_MH &&
		     fl->fl_mh_type <= IP6_MH_TYPE_MAX))
		goto out;

	if (likely(opt->dsthao)) {
		offset = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
		if (likely(offset >= 0))
			hao = (struct ipv6_destopt_hao *)
					(skb_network_header(skb) + offset);
	}

	skb_get_timestamp(skb, &stamp);

	if (!mip6_report_rl_allow(&stamp, &ipv6_hdr(skb)->daddr,
				  hao ? &hao->addr : &ipv6_hdr(skb)->saddr,
				  opt->iif))
		goto out;

	memset(&sel, 0, sizeof(sel));
	memcpy(&sel.daddr, (xfrm_address_t *)&ipv6_hdr(skb)->daddr,
	       sizeof(sel.daddr));
	sel.prefixlen_d = 128;
	memcpy(&sel.saddr, (xfrm_address_t *)&ipv6_hdr(skb)->saddr,
	       sizeof(sel.saddr));
	sel.prefixlen_s = 128;
	sel.family = AF_INET6;
	sel.proto = fl->proto;
	sel.dport = xfrm_flowi_dport(fl);
	if (sel.dport)
		sel.dport_mask = htons(~0);
	sel.sport = xfrm_flowi_sport(fl);
	if (sel.sport)
		sel.sport_mask = htons(~0);
	sel.ifindex = fl->oif;

	err = km_report(IPPROTO_DSTOPTS, &sel,
			(hao ? (xfrm_address_t *)&hao->addr : NULL));

 out:
	return err;
}

static int mip6_destopt_offset(struct xfrm_state *x, struct sk_buff *skb,
			       u8 **nexthdr)
{
	u16 offset = sizeof(struct ipv6hdr);
	struct ipv6_opt_hdr *exthdr =
				   (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
	const unsigned char *nh = skb_network_header(skb);
	unsigned int packet_len = skb->tail - skb->network_header;
	int found_rhdr = 0;

	*nexthdr = &ipv6_hdr(skb)->nexthdr;

	while (offset + 1 <= packet_len) {

		switch (**nexthdr) {
		case NEXTHDR_HOP:
			break;
		case NEXTHDR_ROUTING:
			found_rhdr = 1;
			break;
		case NEXTHDR_DEST:
			/*
			 * HAO MUST NOT appear more than once.
			 * XXX: It is better to try to find by the end of
			 * XXX: packet if HAO exists.
			 */
			if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) {
				LIMIT_NETDEBUG(KERN_WARNING "mip6: hao exists already, override\n");
				return offset;
			}

			if (found_rhdr)
				return offset;

			break;
		default:
			return offset;
		}

		offset += ipv6_optlen(exthdr);
		*nexthdr = &exthdr->nexthdr;
		exthdr = (struct ipv6_opt_hdr *)(nh + offset);
	}

	return offset;
}

static int mip6_destopt_init_state(struct xfrm_state *x)
{
	if (x->id.spi) {
		printk(KERN_INFO "%s: spi is not 0: %u\n", __func__,
		       x->id.spi);
		return -EINVAL;
	}
	if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
		printk(KERN_INFO "%s: state's mode is not %u: %u\n",
		       __func__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
		return -EINVAL;
	}

	x->props.header_len = sizeof(struct ipv6_destopt_hdr) +
		calc_padlen(sizeof(struct ipv6_destopt_hdr), 6) +
		sizeof(struct ipv6_destopt_hao);
	BUG_TRAP(x->props.header_len == 24);

	return 0;
}

/*
 * Do nothing about destroying since it has no specific operation for
 * destination options header unlike IPsec protocols.
 */
static void mip6_destopt_destroy(struct xfrm_state *x)
{
}

static const struct xfrm_type mip6_destopt_type =
{
	.description	= "MIP6DESTOPT",
	.owner		= THIS_MODULE,
	.proto	     	= IPPROTO_DSTOPTS,
	.flags		= XFRM_TYPE_NON_FRAGMENT | XFRM_TYPE_LOCAL_COADDR,
	.init_state	= mip6_destopt_init_state,
	.destructor	= mip6_destopt_destroy,
	.input		= mip6_destopt_input,
	.output		= mip6_destopt_output,
	.reject		= mip6_destopt_reject,
	.hdr_offset	= mip6_destopt_offset,
};

static int mip6_rthdr_input(struct xfrm_state *x, struct sk_buff *skb)
{
	struct rt2_hdr *rt2 = (struct rt2_hdr *)skb->data;
	int err = rt2->rt_hdr.nexthdr;

	spin_lock(&x->lock);
	if (!ipv6_addr_equal(&rt2->addr, (struct in6_addr *)x->coaddr) &&
	    !ipv6_addr_any((struct in6_addr *)x->coaddr))
		err = -ENOENT;
	spin_unlock(&x->lock);

	return err;
}

/* Routing Header type 2 is inserted.
 * IP Header's dst address is replaced with Routing Header's Home Address.
 */
static int mip6_rthdr_output(struct xfrm_state *x, struct sk_buff *skb)
{
	struct ipv6hdr *iph;
	struct rt2_hdr *rt2;
	u8 nexthdr;

	skb_push(skb, -skb_network_offset(skb));
	iph = ipv6_hdr(skb);

	nexthdr = *skb_mac_header(skb);
	*skb_mac_header(skb) = IPPROTO_ROUTING;

	rt2 = (struct rt2_hdr *)skb_transport_header(skb);
	rt2->rt_hdr.nexthdr = nexthdr;
	rt2->rt_hdr.hdrlen = (x->props.header_len >> 3) - 1;
	rt2->rt_hdr.type = IPV6_SRCRT_TYPE_2;
	rt2->rt_hdr.segments_left = 1;
	memset(&rt2->reserved, 0, sizeof(rt2->reserved));

	BUG_TRAP(rt2->rt_hdr.hdrlen == 2);

	memcpy(&rt2->addr, &iph->daddr, sizeof(rt2->addr));
	spin_lock_bh(&x->lock);
	memcpy(&iph->daddr, x->coaddr, sizeof(iph->daddr));
	spin_unlock_bh(&x->lock);

	return 0;
}

static int mip6_rthdr_offset(struct xfrm_state *x, struct sk_buff *skb,
			     u8 **nexthdr)
{
	u16 offset = sizeof(struct ipv6hdr);
	struct ipv6_opt_hdr *exthdr =
				   (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
	const unsigned char *nh = skb_network_header(skb);
	unsigned int packet_len = skb->tail - skb->network_header;
	int found_rhdr = 0;

	*nexthdr = &ipv6_hdr(skb)->nexthdr;

	while (offset + 1 <= packet_len) {

		switch (**nexthdr) {
		case NEXTHDR_HOP:
			break;
		case NEXTHDR_ROUTING:
			if (offset + 3 <= packet_len) {
				struct ipv6_rt_hdr *rt;
				rt = (struct ipv6_rt_hdr *)(nh + offset);
				if (rt->type != 0)
					return offset;
			}
			found_rhdr = 1;
			break;
		case NEXTHDR_DEST:
			if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
				return offset;

			if (found_rhdr)
				return offset;

			break;
		default:
			return offset;
		}

		offset += ipv6_optlen(exthdr);
		*nexthdr = &exthdr->nexthdr;
		exthdr = (struct ipv6_opt_hdr *)(nh + offset);
	}

	return offset;
}

static int mip6_rthdr_init_state(struct xfrm_state *x)
{
	if (x->id.spi) {
		printk(KERN_INFO "%s: spi is not 0: %u\n", __func__,
		       x->id.spi);
		return -EINVAL;
	}
	if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
		printk(KERN_INFO "%s: state's mode is not %u: %u\n",
		       __func__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
		return -EINVAL;
	}

	x->props.header_len = sizeof(struct rt2_hdr);

	return 0;
}

/*
 * Do nothing about destroying since it has no specific operation for routing
 * header type 2 unlike IPsec protocols.
 */
static void mip6_rthdr_destroy(struct xfrm_state *x)
{
}

static const struct xfrm_type mip6_rthdr_type =
{
	.description	= "MIP6RT",
	.owner		= THIS_MODULE,
	.proto	     	= IPPROTO_ROUTING,
	.flags		= XFRM_TYPE_NON_FRAGMENT | XFRM_TYPE_REMOTE_COADDR,
	.init_state	= mip6_rthdr_init_state,
	.destructor	= mip6_rthdr_destroy,
	.input		= mip6_rthdr_input,
	.output		= mip6_rthdr_output,
	.hdr_offset	= mip6_rthdr_offset,
};

static int __init mip6_init(void)
{
	printk(KERN_INFO "Mobile IPv6\n");

	if (xfrm_register_type(&mip6_destopt_type, AF_INET6) < 0) {
		printk(KERN_INFO "%s: can't add xfrm type(destopt)\n", __func__);
		goto mip6_destopt_xfrm_fail;
	}
	if (xfrm_register_type(&mip6_rthdr_type, AF_INET6) < 0) {
		printk(KERN_INFO "%s: can't add xfrm type(rthdr)\n", __func__);
		goto mip6_rthdr_xfrm_fail;
	}
	if (rawv6_mh_filter_register(mip6_mh_filter) < 0) {
		printk(KERN_INFO "%s: can't add rawv6 mh filter\n", __func__);
		goto mip6_rawv6_mh_fail;
	}


	return 0;

 mip6_rawv6_mh_fail:
	xfrm_unregister_type(&mip6_rthdr_type, AF_INET6);
 mip6_rthdr_xfrm_fail:
	xfrm_unregister_type(&mip6_destopt_type, AF_INET6);
 mip6_destopt_xfrm_fail:
	return -EAGAIN;
}

static void __exit mip6_fini(void)
{
	if (rawv6_mh_filter_unregister(mip6_mh_filter) < 0)
		printk(KERN_INFO "%s: can't remove rawv6 mh filter\n", __func__);
	if (xfrm_unregister_type(&mip6_rthdr_type, AF_INET6) < 0)
		printk(KERN_INFO "%s: can't remove xfrm type(rthdr)\n", __func__);
	if (xfrm_unregister_type(&mip6_destopt_type, AF_INET6) < 0)
		printk(KERN_INFO "%s: can't remove xfrm type(destopt)\n", __func__);
}

module_init(mip6_init);
module_exit(mip6_fini);

MODULE_LICENSE("GPL");
MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_DSTOPTS);
MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ROUTING);
Commit	Line	Data
2c8d7ca0 NT	1	/*
	2	* Copyright (C)2003-2006 Helsinki University of Technology
	3	* Copyright (C)2003-2006 USAGI/WIDE Project
	4	*
	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License as published by
	7	* the Free Software Foundation; either version 2 of the License, or
	8	* (at your option) any later version.
	9	*
	10	* This program is distributed in the hope that it will be useful,
	11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	* GNU General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public License
	16	* along with this program; if not, write to the Free Software
	17	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	18	*/
	19	/*
	20	* Authors:
	21	* Noriaki TAKAMIYA @USAGI
	22	* Masahide NAKAMURA @USAGI
	23	*/
	24
2c8d7ca0 NT	25	#include <linux/module.h>
2c8d7ca0 NT	26	#include <linux/skbuff.h>
70182ed2	27	#include <linux/time.h>
2c8d7ca0	28	#include <linux/ipv6.h>
7be96f76 MN	29	#include <linux/icmpv6.h>
7be96f76 MN	30	#include <net/sock.h>
2c8d7ca0	31	#include <net/ipv6.h>
7be96f76	32	#include <net/ip6_checksum.h>
59fbb3a6	33	#include <net/rawv6.h>
2c8d7ca0 NT	34	#include <net/xfrm.h>
	35	#include <net/mip6.h>
	36
3d126890 NT	37	static inline unsigned int calc_padlen(unsigned int len, unsigned int n)
	38	{
	39	return (n - len + 16) & 0x7;
	40	}
	41
	42	static inline void mip6_padn(__u8 data, __u8 padlen)
	43	{
	44	if (!data)
	45	return NULL;
	46	if (padlen == 1) {
	47	data[0] = MIP6_OPT_PAD_1;
	48	} else if (padlen > 1) {
	49	data[0] = MIP6_OPT_PAD_N;
	50	data[1] = padlen - 2;
	51	if (padlen > 2)
	52	memset(data+2, 0, data[1]);
	53	}
	54	return data + padlen;
	55	}
	56
7be96f76 MN	57	static inline void mip6_param_prob(struct sk_buff *skb, int code, int pos)
	58	{
	59	icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos, skb->dev);
	60	}
	61
	62	static int mip6_mh_len(int type)
	63	{
	64	int len = 0;
	65
	66	switch (type) {
	67	case IP6_MH_TYPE_BRR:
	68	len = 0;
	69	break;
	70	case IP6_MH_TYPE_HOTI:
	71	case IP6_MH_TYPE_COTI:
	72	case IP6_MH_TYPE_BU:
	73	case IP6_MH_TYPE_BACK:
	74	len = 1;
	75	break;
	76	case IP6_MH_TYPE_HOT:
	77	case IP6_MH_TYPE_COT:
	78	case IP6_MH_TYPE_BERROR:
	79	len = 2;
	80	break;
	81	}
	82	return len;
	83	}
	84
59fbb3a6	85	static int mip6_mh_filter(struct sock sk, struct sk_buff skb)
7be96f76 MN	86	{
7be96f76 MN	87	struct ip6_mh *mh;
7be96f76	88
ea2ae17d ACM	89	if (!pskb_may_pull(skb, (skb_transport_offset(skb)) + 8) \|\|
ea2ae17d ACM	90	!pskb_may_pull(skb, (skb_transport_offset(skb) +
9c70220b	91	((skb_transport_header(skb)[1] + 1) << 3))))
7be96f76 MN	92	return -1;
7be96f76 MN	93
9c70220b	94	mh = (struct ip6_mh *)skb_transport_header(skb);
7be96f76 MN	95
	96	if (mh->ip6mh_hdrlen < mip6_mh_len(mh->ip6mh_type)) {
	97	LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH message too short: %d vs >=%d\n",
	98	mh->ip6mh_hdrlen, mip6_mh_len(mh->ip6mh_type));
d56f90a7 ACM	99	mip6_param_prob(skb, 0, ((&mh->ip6mh_hdrlen) -
d56f90a7 ACM	100	skb_network_header(skb)));
7be96f76 MN	101	return -1;
7be96f76 MN	102	}
7be96f76 MN	103
	104	if (mh->ip6mh_proto != IPPROTO_NONE) {
	105	LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH invalid payload proto = %d\n",
	106	mh->ip6mh_proto);
d56f90a7 ACM	107	mip6_param_prob(skb, 0, ((&mh->ip6mh_proto) -
d56f90a7 ACM	108	skb_network_header(skb)));
7be96f76 MN	109	return -1;
	110	}
	111
	112	return 0;
	113	}
	114
70182ed2 MN	115	struct mip6_report_rate_limiter {
	116	spinlock_t lock;
	117	struct timeval stamp;
	118	int iif;
	119	struct in6_addr src;
	120	struct in6_addr dst;
	121	};
	122
	123	static struct mip6_report_rate_limiter mip6_report_rl = {
4ef8d0ae	124	.lock = __SPIN_LOCK_UNLOCKED(mip6_report_rl.lock)
70182ed2 MN	125	};
70182ed2 MN	126
3d126890 NT	127	static int mip6_destopt_input(struct xfrm_state x, struct sk_buff skb)
3d126890 NT	128	{
0660e03f	129	struct ipv6hdr *iph = ipv6_hdr(skb);
3d126890	130	struct ipv6_destopt_hdr destopt = (struct ipv6_destopt_hdr )skb->data;
0ebea8ef	131	int err = destopt->nexthdr;
3d126890	132
0ebea8ef	133	spin_lock(&x->lock);
3d126890 NT	134	if (!ipv6_addr_equal(&iph->saddr, (struct in6_addr *)x->coaddr) &&
3d126890 NT	135	!ipv6_addr_any((struct in6_addr *)x->coaddr))
0ebea8ef HX	136	err = -ENOENT;
0ebea8ef HX	137	spin_unlock(&x->lock);
3d126890	138
0ebea8ef	139	return err;
3d126890 NT	140	}
	141
	142	/* Destination Option Header is inserted.
	143	* IP Header's src address is replaced with Home Address Option in
	144	* Destination Option Header.
	145	*/
	146	static int mip6_destopt_output(struct xfrm_state x, struct sk_buff skb)
	147	{
	148	struct ipv6hdr *iph;
	149	struct ipv6_destopt_hdr *dstopt;
	150	struct ipv6_destopt_hao *hao;
	151	u8 nexthdr;
	152	int len;
	153
7b277b1a	154	skb_push(skb, -skb_network_offset(skb));
007f0211	155	iph = ipv6_hdr(skb);
3d126890	156
007f0211 HX	157	nexthdr = *skb_mac_header(skb);
007f0211 HX	158	*skb_mac_header(skb) = IPPROTO_DSTOPTS;
3d126890	159
9c70220b	160	dstopt = (struct ipv6_destopt_hdr *)skb_transport_header(skb);
3d126890 NT	161	dstopt->nexthdr = nexthdr;
	162
	163	hao = mip6_padn((char *)(dstopt + 1),
	164	calc_padlen(sizeof(*dstopt), 6));
	165
	166	hao->type = IPV6_TLV_HAO;
	167	hao->length = sizeof(*hao) - 2;
	168	BUG_TRAP(hao->length == 16);
	169
	170	len = ((char )hao - (char )dstopt) + sizeof(*hao);
	171
	172	memcpy(&hao->addr, &iph->saddr, sizeof(hao->addr));
b7c6538c	173	spin_lock_bh(&x->lock);
3d126890	174	memcpy(&iph->saddr, x->coaddr, sizeof(iph->saddr));
b7c6538c	175	spin_unlock_bh(&x->lock);
3d126890 NT	176
	177	BUG_TRAP(len == x->props.header_len);
	178	dstopt->hdrlen = (x->props.header_len >> 3) - 1;
	179
	180	return 0;
	181	}
	182
70182ed2 MN	183	static inline int mip6_report_rl_allow(struct timeval *stamp,
	184	struct in6_addr *dst,
	185	struct in6_addr *src, int iif)
	186	{
	187	int allow = 0;
	188
	189	spin_lock_bh(&mip6_report_rl.lock);
	190	if (mip6_report_rl.stamp.tv_sec != stamp->tv_sec \|\|
	191	mip6_report_rl.stamp.tv_usec != stamp->tv_usec \|\|
	192	mip6_report_rl.iif != iif \|\|
	193	!ipv6_addr_equal(&mip6_report_rl.src, src) \|\|
	194	!ipv6_addr_equal(&mip6_report_rl.dst, dst)) {
	195	mip6_report_rl.stamp.tv_sec = stamp->tv_sec;
	196	mip6_report_rl.stamp.tv_usec = stamp->tv_usec;
	197	mip6_report_rl.iif = iif;
	198	ipv6_addr_copy(&mip6_report_rl.src, src);
	199	ipv6_addr_copy(&mip6_report_rl.dst, dst);
	200	allow = 1;
	201	}
	202	spin_unlock_bh(&mip6_report_rl.lock);
	203	return allow;
	204	}
	205
	206	static int mip6_destopt_reject(struct xfrm_state x, struct sk_buff skb, struct flowi *fl)
	207	{
	208	struct inet6_skb_parm opt = (struct inet6_skb_parm )skb->cb;
	209	struct ipv6_destopt_hao *hao = NULL;
	210	struct xfrm_selector sel;
	211	int offset;
	212	struct timeval stamp;
	213	int err = 0;
	214
e731c248 YH	215	if (unlikely(fl->proto == IPPROTO_MH &&
e731c248 YH	216	fl->fl_mh_type <= IP6_MH_TYPE_MAX))
01be8e5d MN	217	goto out;
01be8e5d MN	218
70182ed2 MN	219	if (likely(opt->dsthao)) {
	220	offset = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
	221	if (likely(offset >= 0))
d56f90a7 ACM	222	hao = (struct ipv6_destopt_hao *)
d56f90a7 ACM	223	(skb_network_header(skb) + offset);
70182ed2 MN	224	}
	225
	226	skb_get_timestamp(skb, &stamp);
	227
0660e03f ACM	228	if (!mip6_report_rl_allow(&stamp, &ipv6_hdr(skb)->daddr,
0660e03f ACM	229	hao ? &hao->addr : &ipv6_hdr(skb)->saddr,
70182ed2 MN	230	opt->iif))
	231	goto out;
	232
	233	memset(&sel, 0, sizeof(sel));
0660e03f	234	memcpy(&sel.daddr, (xfrm_address_t *)&ipv6_hdr(skb)->daddr,
70182ed2 MN	235	sizeof(sel.daddr));
70182ed2 MN	236	sel.prefixlen_d = 128;
0660e03f	237	memcpy(&sel.saddr, (xfrm_address_t *)&ipv6_hdr(skb)->saddr,
70182ed2 MN	238	sizeof(sel.saddr));
	239	sel.prefixlen_s = 128;
	240	sel.family = AF_INET6;
	241	sel.proto = fl->proto;
	242	sel.dport = xfrm_flowi_dport(fl);
	243	if (sel.dport)
e69a4adc	244	sel.dport_mask = htons(~0);
70182ed2 MN	245	sel.sport = xfrm_flowi_sport(fl);
70182ed2 MN	246	if (sel.sport)
e69a4adc	247	sel.sport_mask = htons(~0);
70182ed2 MN	248	sel.ifindex = fl->oif;
	249
	250	err = km_report(IPPROTO_DSTOPTS, &sel,
	251	(hao ? (xfrm_address_t *)&hao->addr : NULL));
	252
	253	out:
	254	return err;
	255	}
	256
3d126890 NT	257	static int mip6_destopt_offset(struct xfrm_state x, struct sk_buff skb,
	258	u8 **nexthdr)
	259	{
	260	u16 offset = sizeof(struct ipv6hdr);
0660e03f ACM	261	struct ipv6_opt_hdr *exthdr =
0660e03f ACM	262	(struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
d56f90a7	263	const unsigned char *nh = skb_network_header(skb);
27a884dc	264	unsigned int packet_len = skb->tail - skb->network_header;
3d126890 NT	265	int found_rhdr = 0;
3d126890 NT	266
0660e03f	267	*nexthdr = &ipv6_hdr(skb)->nexthdr;
3d126890 NT	268
	269	while (offset + 1 <= packet_len) {
	270
	271	switch (**nexthdr) {
	272	case NEXTHDR_HOP:
	273	break;
	274	case NEXTHDR_ROUTING:
	275	found_rhdr = 1;
	276	break;
	277	case NEXTHDR_DEST:
	278	/*
	279	* HAO MUST NOT appear more than once.
	280	* XXX: It is better to try to find by the end of
	281	* XXX: packet if HAO exists.
	282	*/
	283	if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) {
	284	LIMIT_NETDEBUG(KERN_WARNING "mip6: hao exists already, override\n");
	285	return offset;
	286	}
	287
	288	if (found_rhdr)
	289	return offset;
	290
	291	break;
	292	default:
	293	return offset;
	294	}
	295
	296	offset += ipv6_optlen(exthdr);
	297	*nexthdr = &exthdr->nexthdr;
d56f90a7	298	exthdr = (struct ipv6_opt_hdr *)(nh + offset);
3d126890 NT	299	}
	300
	301	return offset;
	302	}
	303
	304	static int mip6_destopt_init_state(struct xfrm_state *x)
	305	{
	306	if (x->id.spi) {
0dc47877	307	printk(KERN_INFO "%s: spi is not 0: %u\n", __func__,
3d126890 NT	308	x->id.spi);
	309	return -EINVAL;
	310	}
	311	if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
	312	printk(KERN_INFO "%s: state's mode is not %u: %u\n",
0dc47877	313	__func__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
3d126890 NT	314	return -EINVAL;
	315	}
	316
	317	x->props.header_len = sizeof(struct ipv6_destopt_hdr) +
	318	calc_padlen(sizeof(struct ipv6_destopt_hdr), 6) +
	319	sizeof(struct ipv6_destopt_hao);
	320	BUG_TRAP(x->props.header_len == 24);
	321
	322	return 0;
	323	}
	324
	325	/*
	326	* Do nothing about destroying since it has no specific operation for
	327	* destination options header unlike IPsec protocols.
	328	*/
	329	static void mip6_destopt_destroy(struct xfrm_state *x)
	330	{
	331	}
	332
533cb5b0	333	static const struct xfrm_type mip6_destopt_type =
3d126890 NT	334	{
	335	.description = "MIP6DESTOPT",
	336	.owner = THIS_MODULE,
	337	.proto = IPPROTO_DSTOPTS,
f04e7e8d	338	.flags = XFRM_TYPE_NON_FRAGMENT \| XFRM_TYPE_LOCAL_COADDR,
3d126890 NT	339	.init_state = mip6_destopt_init_state,
	340	.destructor = mip6_destopt_destroy,
	341	.input = mip6_destopt_input,
	342	.output = mip6_destopt_output,
1ab1457c	343	.reject = mip6_destopt_reject,
3d126890	344	.hdr_offset = mip6_destopt_offset,
3d126890 NT	345	};
3d126890 NT	346
2c8d7ca0 NT	347	static int mip6_rthdr_input(struct xfrm_state x, struct sk_buff skb)
	348	{
	349	struct rt2_hdr rt2 = (struct rt2_hdr )skb->data;
0ebea8ef	350	int err = rt2->rt_hdr.nexthdr;
2c8d7ca0	351
0ebea8ef	352	spin_lock(&x->lock);
2c8d7ca0 NT	353	if (!ipv6_addr_equal(&rt2->addr, (struct in6_addr *)x->coaddr) &&
2c8d7ca0 NT	354	!ipv6_addr_any((struct in6_addr *)x->coaddr))
0ebea8ef HX	355	err = -ENOENT;
0ebea8ef HX	356	spin_unlock(&x->lock);
2c8d7ca0	357
0ebea8ef	358	return err;
2c8d7ca0 NT	359	}
	360
	361	/* Routing Header type 2 is inserted.
	362	* IP Header's dst address is replaced with Routing Header's Home Address.
	363	*/
	364	static int mip6_rthdr_output(struct xfrm_state x, struct sk_buff skb)
	365	{
	366	struct ipv6hdr *iph;
	367	struct rt2_hdr *rt2;
	368	u8 nexthdr;
	369
7b277b1a	370	skb_push(skb, -skb_network_offset(skb));
007f0211	371	iph = ipv6_hdr(skb);
2c8d7ca0	372
007f0211 HX	373	nexthdr = *skb_mac_header(skb);
007f0211 HX	374	*skb_mac_header(skb) = IPPROTO_ROUTING;
2c8d7ca0	375
9c70220b	376	rt2 = (struct rt2_hdr *)skb_transport_header(skb);
2c8d7ca0 NT	377	rt2->rt_hdr.nexthdr = nexthdr;
	378	rt2->rt_hdr.hdrlen = (x->props.header_len >> 3) - 1;
	379	rt2->rt_hdr.type = IPV6_SRCRT_TYPE_2;
	380	rt2->rt_hdr.segments_left = 1;
	381	memset(&rt2->reserved, 0, sizeof(rt2->reserved));
	382
	383	BUG_TRAP(rt2->rt_hdr.hdrlen == 2);
	384
	385	memcpy(&rt2->addr, &iph->daddr, sizeof(rt2->addr));
b7c6538c	386	spin_lock_bh(&x->lock);
2c8d7ca0	387	memcpy(&iph->daddr, x->coaddr, sizeof(iph->daddr));
b7c6538c	388	spin_unlock_bh(&x->lock);
2c8d7ca0 NT	389
	390	return 0;
	391	}
	392
	393	static int mip6_rthdr_offset(struct xfrm_state x, struct sk_buff skb,
	394	u8 **nexthdr)
	395	{
	396	u16 offset = sizeof(struct ipv6hdr);
0660e03f ACM	397	struct ipv6_opt_hdr *exthdr =
0660e03f ACM	398	(struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
d56f90a7	399	const unsigned char *nh = skb_network_header(skb);
27a884dc	400	unsigned int packet_len = skb->tail - skb->network_header;
2c8d7ca0 NT	401	int found_rhdr = 0;
2c8d7ca0 NT	402
0660e03f	403	*nexthdr = &ipv6_hdr(skb)->nexthdr;
2c8d7ca0 NT	404
	405	while (offset + 1 <= packet_len) {
	406
	407	switch (**nexthdr) {
	408	case NEXTHDR_HOP:
	409	break;
	410	case NEXTHDR_ROUTING:
	411	if (offset + 3 <= packet_len) {
	412	struct ipv6_rt_hdr *rt;
d56f90a7	413	rt = (struct ipv6_rt_hdr *)(nh + offset);
2c8d7ca0 NT	414	if (rt->type != 0)
	415	return offset;
	416	}
	417	found_rhdr = 1;
	418	break;
	419	case NEXTHDR_DEST:
	420	if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
	421	return offset;
	422
	423	if (found_rhdr)
	424	return offset;
	425
	426	break;
	427	default:
	428	return offset;
	429	}
	430
	431	offset += ipv6_optlen(exthdr);
	432	*nexthdr = &exthdr->nexthdr;
d56f90a7	433	exthdr = (struct ipv6_opt_hdr *)(nh + offset);
2c8d7ca0 NT	434	}
	435
	436	return offset;
	437	}
	438
	439	static int mip6_rthdr_init_state(struct xfrm_state *x)
	440	{
	441	if (x->id.spi) {
0dc47877	442	printk(KERN_INFO "%s: spi is not 0: %u\n", __func__,
2c8d7ca0 NT	443	x->id.spi);
	444	return -EINVAL;
	445	}
	446	if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
	447	printk(KERN_INFO "%s: state's mode is not %u: %u\n",
0dc47877	448	__func__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
2c8d7ca0 NT	449	return -EINVAL;
	450	}
	451
	452	x->props.header_len = sizeof(struct rt2_hdr);
	453
	454	return 0;
	455	}
	456
	457	/*
	458	* Do nothing about destroying since it has no specific operation for routing
	459	* header type 2 unlike IPsec protocols.
	460	*/
	461	static void mip6_rthdr_destroy(struct xfrm_state *x)
	462	{
	463	}
	464
533cb5b0	465	static const struct xfrm_type mip6_rthdr_type =
2c8d7ca0 NT	466	{
	467	.description = "MIP6RT",
	468	.owner = THIS_MODULE,
	469	.proto = IPPROTO_ROUTING,
f04e7e8d	470	.flags = XFRM_TYPE_NON_FRAGMENT \| XFRM_TYPE_REMOTE_COADDR,
2c8d7ca0 NT	471	.init_state = mip6_rthdr_init_state,
	472	.destructor = mip6_rthdr_destroy,
	473	.input = mip6_rthdr_input,
	474	.output = mip6_rthdr_output,
	475	.hdr_offset = mip6_rthdr_offset,
2c8d7ca0 NT	476	};
2c8d7ca0 NT	477
59fbb3a6	478	static int __init mip6_init(void)
2c8d7ca0 NT	479	{
	480	printk(KERN_INFO "Mobile IPv6\n");
	481
3d126890	482	if (xfrm_register_type(&mip6_destopt_type, AF_INET6) < 0) {
0dc47877	483	printk(KERN_INFO "%s: can't add xfrm type(destopt)\n", __func__);
3d126890 NT	484	goto mip6_destopt_xfrm_fail;
3d126890 NT	485	}
2c8d7ca0	486	if (xfrm_register_type(&mip6_rthdr_type, AF_INET6) < 0) {
0dc47877	487	printk(KERN_INFO "%s: can't add xfrm type(rthdr)\n", __func__);
2c8d7ca0 NT	488	goto mip6_rthdr_xfrm_fail;
2c8d7ca0 NT	489	}
59fbb3a6	490	if (rawv6_mh_filter_register(mip6_mh_filter) < 0) {
0dc47877	491	printk(KERN_INFO "%s: can't add rawv6 mh filter\n", __func__);
59fbb3a6 MN	492	goto mip6_rawv6_mh_fail;
	493	}
	494
	495
2c8d7ca0 NT	496	return 0;
2c8d7ca0 NT	497
59fbb3a6 MN	498	mip6_rawv6_mh_fail:
59fbb3a6 MN	499	xfrm_unregister_type(&mip6_rthdr_type, AF_INET6);
2c8d7ca0	500	mip6_rthdr_xfrm_fail:
3d126890 NT	501	xfrm_unregister_type(&mip6_destopt_type, AF_INET6);
3d126890 NT	502	mip6_destopt_xfrm_fail:
2c8d7ca0 NT	503	return -EAGAIN;
	504	}
	505
59fbb3a6	506	static void __exit mip6_fini(void)
2c8d7ca0	507	{
59fbb3a6	508	if (rawv6_mh_filter_unregister(mip6_mh_filter) < 0)
0dc47877	509	printk(KERN_INFO "%s: can't remove rawv6 mh filter\n", __func__);
2c8d7ca0	510	if (xfrm_unregister_type(&mip6_rthdr_type, AF_INET6) < 0)
0dc47877	511	printk(KERN_INFO "%s: can't remove xfrm type(rthdr)\n", __func__);
3d126890	512	if (xfrm_unregister_type(&mip6_destopt_type, AF_INET6) < 0)
0dc47877	513	printk(KERN_INFO "%s: can't remove xfrm type(destopt)\n", __func__);
2c8d7ca0	514	}
59fbb3a6 MN	515
	516	module_init(mip6_init);
	517	module_exit(mip6_fini);
	518
	519	MODULE_LICENSE("GPL");
d3d6dd3a MN	520	MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_DSTOPTS);
d3d6dd3a MN	521	MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ROUTING);