[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/xfrm.h>
#include <net/mip6.h>

static xfrm_address_t *mip6_xfrm_addr(struct xfrm_state *x, xfrm_address_t *addr)
{
	return x->coaddr;
}

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;
}

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

	if (!pskb_may_pull(skb, (skb->h.raw - skb->data) + 8) ||
	    !pskb_may_pull(skb, (skb->h.raw - skb->data) + ((skb->h.raw[1] + 1) << 3)))
		return -1;

	mh = (struct ip6_mh *)skb->h.raw;

	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->nh.raw);
		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->nh.raw);
		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
};

static int mip6_destopt_input(struct xfrm_state *x, struct sk_buff *skb)
{
	struct ipv6hdr *iph = skb->nh.ipv6h;
	struct ipv6_destopt_hdr *destopt = (struct ipv6_destopt_hdr *)skb->data;

	if (!ipv6_addr_equal(&iph->saddr, (struct in6_addr *)x->coaddr) &&
	    !ipv6_addr_any((struct in6_addr *)x->coaddr))
		return -ENOENT;

	return destopt->nexthdr;
}

/* 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;

	iph = (struct ipv6hdr *)skb->data;
	iph->payload_len = htons(skb->len - sizeof(*iph));

	nexthdr = *skb->nh.raw;
	*skb->nh.raw = IPPROTO_DSTOPTS;

	dstopt = (struct ipv6_destopt_hdr *)skb->h.raw;
	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));
	memcpy(&iph->saddr, x->coaddr, sizeof(iph->saddr));

	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->nh.raw + offset);
	}

	skb_get_timestamp(skb, &stamp);

	if (!mip6_report_rl_allow(&stamp, &skb->nh.ipv6h->daddr,
				  hao ? &hao->addr : &skb->nh.ipv6h->saddr,
				  opt->iif))
		goto out;

	memset(&sel, 0, sizeof(sel));
	memcpy(&sel.daddr, (xfrm_address_t *)&skb->nh.ipv6h->daddr,
	       sizeof(sel.daddr));
	sel.prefixlen_d = 128;
	memcpy(&sel.saddr, (xfrm_address_t *)&skb->nh.ipv6h->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*)(skb->nh.ipv6h + 1);
	unsigned int packet_len = skb->tail - skb->nh.raw;
	int found_rhdr = 0;

	*nexthdr = &skb->nh.ipv6h->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*)(skb->nh.raw + 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", __FUNCTION__,
		       x->id.spi);
		return -EINVAL;
	}
	if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
		printk(KERN_INFO "%s: state's mode is not %u: %u\n",
		       __FUNCTION__, 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 struct xfrm_type mip6_destopt_type =
{
	.description	= "MIP6DESTOPT",
	.owner		= THIS_MODULE,
	.proto	     	= IPPROTO_DSTOPTS,
	.flags		= XFRM_TYPE_NON_FRAGMENT,
	.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,
	.local_addr	= mip6_xfrm_addr,
};

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

	if (!ipv6_addr_equal(&rt2->addr, (struct in6_addr *)x->coaddr) &&
	    !ipv6_addr_any((struct in6_addr *)x->coaddr))
		return -ENOENT;

	return rt2->rt_hdr.nexthdr;
}

/* 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;

	iph = (struct ipv6hdr *)skb->data;
	iph->payload_len = htons(skb->len - sizeof(*iph));

	nexthdr = *skb->nh.raw;
	*skb->nh.raw = IPPROTO_ROUTING;

	rt2 = (struct rt2_hdr *)skb->h.raw;
	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));
	memcpy(&iph->daddr, x->coaddr, sizeof(iph->daddr));

	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*)(skb->nh.ipv6h + 1);
	unsigned int packet_len = skb->tail - skb->nh.raw;
	int found_rhdr = 0;

	*nexthdr = &skb->nh.ipv6h->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 *)(skb->nh.raw + 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*)(skb->nh.raw + 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", __FUNCTION__,
		       x->id.spi);
		return -EINVAL;
	}
	if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
		printk(KERN_INFO "%s: state's mode is not %u: %u\n",
		       __FUNCTION__, 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 struct xfrm_type mip6_rthdr_type =
{
	.description	= "MIP6RT",
	.owner		= THIS_MODULE,
	.proto	     	= IPPROTO_ROUTING,
	.flags		= XFRM_TYPE_NON_FRAGMENT,
	.init_state	= mip6_rthdr_init_state,
	.destructor	= mip6_rthdr_destroy,
	.input		= mip6_rthdr_input,
	.output		= mip6_rthdr_output,
	.hdr_offset	= mip6_rthdr_offset,
	.remote_addr	= mip6_xfrm_addr,
};

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", __FUNCTION__);
		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", __FUNCTION__);
		goto mip6_rthdr_xfrm_fail;
	}
	return 0;

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

void __exit mip6_fini(void)
{
	if (xfrm_unregister_type(&mip6_rthdr_type, AF_INET6) < 0)
		printk(KERN_INFO "%s: can't remove xfrm type(rthdr)\n", __FUNCTION__);
	if (xfrm_unregister_type(&mip6_destopt_type, AF_INET6) < 0)
		printk(KERN_INFO "%s: can't remove xfrm type(destopt)\n", __FUNCTION__);
}
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>
2c8d7ca0 NT	33	#include <net/xfrm.h>
	34	#include <net/mip6.h>
	35
	36	static xfrm_address_t mip6_xfrm_addr(struct xfrm_state x, xfrm_address_t *addr)
	37	{
	38	return x->coaddr;
	39	}
	40
3d126890 NT	41	static inline unsigned int calc_padlen(unsigned int len, unsigned int n)
	42	{
	43	return (n - len + 16) & 0x7;
	44	}
	45
	46	static inline void mip6_padn(__u8 data, __u8 padlen)
	47	{
	48	if (!data)
	49	return NULL;
	50	if (padlen == 1) {
	51	data[0] = MIP6_OPT_PAD_1;
	52	} else if (padlen > 1) {
	53	data[0] = MIP6_OPT_PAD_N;
	54	data[1] = padlen - 2;
	55	if (padlen > 2)
	56	memset(data+2, 0, data[1]);
	57	}
	58	return data + padlen;
	59	}
	60
7be96f76 MN	61	static inline void mip6_param_prob(struct sk_buff *skb, int code, int pos)
	62	{
	63	icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos, skb->dev);
	64	}
	65
	66	static int mip6_mh_len(int type)
	67	{
	68	int len = 0;
	69
	70	switch (type) {
	71	case IP6_MH_TYPE_BRR:
	72	len = 0;
	73	break;
	74	case IP6_MH_TYPE_HOTI:
	75	case IP6_MH_TYPE_COTI:
	76	case IP6_MH_TYPE_BU:
	77	case IP6_MH_TYPE_BACK:
	78	len = 1;
	79	break;
	80	case IP6_MH_TYPE_HOT:
	81	case IP6_MH_TYPE_COT:
	82	case IP6_MH_TYPE_BERROR:
	83	len = 2;
	84	break;
	85	}
	86	return len;
	87	}
	88
	89	int mip6_mh_filter(struct sock sk, struct sk_buff skb)
	90	{
	91	struct ip6_mh *mh;
7be96f76 MN	92
	93	if (!pskb_may_pull(skb, (skb->h.raw - skb->data) + 8) \|\|
	94	!pskb_may_pull(skb, (skb->h.raw - skb->data) + ((skb->h.raw[1] + 1) << 3)))
	95	return -1;
	96
	97	mh = (struct ip6_mh *)skb->h.raw;
	98
	99	if (mh->ip6mh_hdrlen < mip6_mh_len(mh->ip6mh_type)) {
	100	LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH message too short: %d vs >=%d\n",
	101	mh->ip6mh_hdrlen, mip6_mh_len(mh->ip6mh_type));
	102	mip6_param_prob(skb, 0, (&mh->ip6mh_hdrlen) - skb->nh.raw);
	103	return -1;
	104	}
7be96f76 MN	105
	106	if (mh->ip6mh_proto != IPPROTO_NONE) {
	107	LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH invalid payload proto = %d\n",
	108	mh->ip6mh_proto);
	109	mip6_param_prob(skb, 0, (&mh->ip6mh_proto) - skb->nh.raw);
	110	return -1;
	111	}
	112
	113	return 0;
	114	}
	115
70182ed2 MN	116	struct mip6_report_rate_limiter {
	117	spinlock_t lock;
	118	struct timeval stamp;
	119	int iif;
	120	struct in6_addr src;
	121	struct in6_addr dst;
	122	};
	123
	124	static struct mip6_report_rate_limiter mip6_report_rl = {
	125	.lock = SPIN_LOCK_UNLOCKED
	126	};
	127
3d126890 NT	128	static int mip6_destopt_input(struct xfrm_state x, struct sk_buff skb)
	129	{
	130	struct ipv6hdr *iph = skb->nh.ipv6h;
	131	struct ipv6_destopt_hdr destopt = (struct ipv6_destopt_hdr )skb->data;
	132
	133	if (!ipv6_addr_equal(&iph->saddr, (struct in6_addr *)x->coaddr) &&
	134	!ipv6_addr_any((struct in6_addr *)x->coaddr))
	135	return -ENOENT;
	136
	137	return destopt->nexthdr;
	138	}
	139
	140	/* Destination Option Header is inserted.
	141	* IP Header's src address is replaced with Home Address Option in
	142	* Destination Option Header.
	143	*/
	144	static int mip6_destopt_output(struct xfrm_state x, struct sk_buff skb)
	145	{
	146	struct ipv6hdr *iph;
	147	struct ipv6_destopt_hdr *dstopt;
	148	struct ipv6_destopt_hao *hao;
	149	u8 nexthdr;
	150	int len;
	151
	152	iph = (struct ipv6hdr *)skb->data;
	153	iph->payload_len = htons(skb->len - sizeof(*iph));
	154
	155	nexthdr = *skb->nh.raw;
	156	*skb->nh.raw = IPPROTO_DSTOPTS;
	157
	158	dstopt = (struct ipv6_destopt_hdr *)skb->h.raw;
	159	dstopt->nexthdr = nexthdr;
	160
	161	hao = mip6_padn((char *)(dstopt + 1),
	162	calc_padlen(sizeof(*dstopt), 6));
	163
	164	hao->type = IPV6_TLV_HAO;
	165	hao->length = sizeof(*hao) - 2;
	166	BUG_TRAP(hao->length == 16);
	167
	168	len = ((char )hao - (char )dstopt) + sizeof(*hao);
	169
	170	memcpy(&hao->addr, &iph->saddr, sizeof(hao->addr));
	171	memcpy(&iph->saddr, x->coaddr, sizeof(iph->saddr));
	172
	173	BUG_TRAP(len == x->props.header_len);
	174	dstopt->hdrlen = (x->props.header_len >> 3) - 1;
	175
	176	return 0;
	177	}
	178
70182ed2 MN	179	static inline int mip6_report_rl_allow(struct timeval *stamp,
	180	struct in6_addr *dst,
	181	struct in6_addr *src, int iif)
	182	{
	183	int allow = 0;
	184
	185	spin_lock_bh(&mip6_report_rl.lock);
	186	if (mip6_report_rl.stamp.tv_sec != stamp->tv_sec \|\|
	187	mip6_report_rl.stamp.tv_usec != stamp->tv_usec \|\|
	188	mip6_report_rl.iif != iif \|\|
	189	!ipv6_addr_equal(&mip6_report_rl.src, src) \|\|
	190	!ipv6_addr_equal(&mip6_report_rl.dst, dst)) {
	191	mip6_report_rl.stamp.tv_sec = stamp->tv_sec;
	192	mip6_report_rl.stamp.tv_usec = stamp->tv_usec;
	193	mip6_report_rl.iif = iif;
	194	ipv6_addr_copy(&mip6_report_rl.src, src);
	195	ipv6_addr_copy(&mip6_report_rl.dst, dst);
	196	allow = 1;
	197	}
	198	spin_unlock_bh(&mip6_report_rl.lock);
	199	return allow;
	200	}
	201
	202	static int mip6_destopt_reject(struct xfrm_state x, struct sk_buff skb, struct flowi *fl)
	203	{
	204	struct inet6_skb_parm opt = (struct inet6_skb_parm )skb->cb;
	205	struct ipv6_destopt_hao *hao = NULL;
	206	struct xfrm_selector sel;
	207	int offset;
	208	struct timeval stamp;
	209	int err = 0;
	210
e731c248 YH	211	if (unlikely(fl->proto == IPPROTO_MH &&
e731c248 YH	212	fl->fl_mh_type <= IP6_MH_TYPE_MAX))
01be8e5d MN	213	goto out;
01be8e5d MN	214
70182ed2 MN	215	if (likely(opt->dsthao)) {
	216	offset = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
	217	if (likely(offset >= 0))
	218	hao = (struct ipv6_destopt_hao *)(skb->nh.raw + offset);
	219	}
	220
	221	skb_get_timestamp(skb, &stamp);
	222
	223	if (!mip6_report_rl_allow(&stamp, &skb->nh.ipv6h->daddr,
	224	hao ? &hao->addr : &skb->nh.ipv6h->saddr,
	225	opt->iif))
	226	goto out;
	227
	228	memset(&sel, 0, sizeof(sel));
	229	memcpy(&sel.daddr, (xfrm_address_t *)&skb->nh.ipv6h->daddr,
	230	sizeof(sel.daddr));
	231	sel.prefixlen_d = 128;
	232	memcpy(&sel.saddr, (xfrm_address_t *)&skb->nh.ipv6h->saddr,
	233	sizeof(sel.saddr));
	234	sel.prefixlen_s = 128;
	235	sel.family = AF_INET6;
	236	sel.proto = fl->proto;
	237	sel.dport = xfrm_flowi_dport(fl);
	238	if (sel.dport)
e69a4adc	239	sel.dport_mask = htons(~0);
70182ed2 MN	240	sel.sport = xfrm_flowi_sport(fl);
70182ed2 MN	241	if (sel.sport)
e69a4adc	242	sel.sport_mask = htons(~0);
70182ed2 MN	243	sel.ifindex = fl->oif;
	244
	245	err = km_report(IPPROTO_DSTOPTS, &sel,
	246	(hao ? (xfrm_address_t *)&hao->addr : NULL));
	247
	248	out:
	249	return err;
	250	}
	251
3d126890 NT	252	static int mip6_destopt_offset(struct xfrm_state x, struct sk_buff skb,
	253	u8 **nexthdr)
	254	{
	255	u16 offset = sizeof(struct ipv6hdr);
	256	struct ipv6_opt_hdr exthdr = (struct ipv6_opt_hdr)(skb->nh.ipv6h + 1);
	257	unsigned int packet_len = skb->tail - skb->nh.raw;
	258	int found_rhdr = 0;
	259
	260	*nexthdr = &skb->nh.ipv6h->nexthdr;
	261
	262	while (offset + 1 <= packet_len) {
	263
	264	switch (**nexthdr) {
	265	case NEXTHDR_HOP:
	266	break;
	267	case NEXTHDR_ROUTING:
	268	found_rhdr = 1;
	269	break;
	270	case NEXTHDR_DEST:
	271	/*
	272	* HAO MUST NOT appear more than once.
	273	* XXX: It is better to try to find by the end of
	274	* XXX: packet if HAO exists.
	275	*/
	276	if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) {
	277	LIMIT_NETDEBUG(KERN_WARNING "mip6: hao exists already, override\n");
	278	return offset;
	279	}
	280
	281	if (found_rhdr)
	282	return offset;
	283
	284	break;
	285	default:
	286	return offset;
	287	}
	288
	289	offset += ipv6_optlen(exthdr);
	290	*nexthdr = &exthdr->nexthdr;
	291	exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
	292	}
	293
	294	return offset;
	295	}
	296
	297	static int mip6_destopt_init_state(struct xfrm_state *x)
	298	{
	299	if (x->id.spi) {
	300	printk(KERN_INFO "%s: spi is not 0: %u\n", __FUNCTION__,
	301	x->id.spi);
	302	return -EINVAL;
	303	}
	304	if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
	305	printk(KERN_INFO "%s: state's mode is not %u: %u\n",
	306	__FUNCTION__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
	307	return -EINVAL;
	308	}
	309
	310	x->props.header_len = sizeof(struct ipv6_destopt_hdr) +
	311	calc_padlen(sizeof(struct ipv6_destopt_hdr), 6) +
	312	sizeof(struct ipv6_destopt_hao);
	313	BUG_TRAP(x->props.header_len == 24);
	314
	315	return 0;
316	}
317
318	/*
319	* Do nothing about destroying since it has no specific operation for
320	* destination options header unlike IPsec protocols.
321	*/
322	static void mip6_destopt_destroy(struct xfrm_state *x)
323	{
324	}
325
326	static struct xfrm_type mip6_destopt_type =
327	{
328	.description = "MIP6DESTOPT",
329	.owner = THIS_MODULE,
330	.proto = IPPROTO_DSTOPTS,
331	.flags = XFRM_TYPE_NON_FRAGMENT,
332	.init_state = mip6_destopt_init_state,
333	.destructor = mip6_destopt_destroy,
334	.input = mip6_destopt_input,
335	.output = mip6_destopt_output,
1ab1457c	336	.reject = mip6_destopt_reject,
3d126890 NT	337	.hdr_offset = mip6_destopt_offset,
	338	.local_addr = mip6_xfrm_addr,
	339	};
	340
2c8d7ca0 NT	341	static int mip6_rthdr_input(struct xfrm_state x, struct sk_buff skb)
	342	{
	343	struct rt2_hdr rt2 = (struct rt2_hdr )skb->data;
	344
	345	if (!ipv6_addr_equal(&rt2->addr, (struct in6_addr *)x->coaddr) &&
	346	!ipv6_addr_any((struct in6_addr *)x->coaddr))
	347	return -ENOENT;
	348
	349	return rt2->rt_hdr.nexthdr;
	350	}
	351
	352	/* Routing Header type 2 is inserted.
	353	* IP Header's dst address is replaced with Routing Header's Home Address.
	354	*/
	355	static int mip6_rthdr_output(struct xfrm_state x, struct sk_buff skb)
	356	{
	357	struct ipv6hdr *iph;
	358	struct rt2_hdr *rt2;
	359	u8 nexthdr;
	360
	361	iph = (struct ipv6hdr *)skb->data;
	362	iph->payload_len = htons(skb->len - sizeof(*iph));
	363
	364	nexthdr = *skb->nh.raw;
	365	*skb->nh.raw = IPPROTO_ROUTING;
	366
	367	rt2 = (struct rt2_hdr *)skb->h.raw;
	368	rt2->rt_hdr.nexthdr = nexthdr;
	369	rt2->rt_hdr.hdrlen = (x->props.header_len >> 3) - 1;
	370	rt2->rt_hdr.type = IPV6_SRCRT_TYPE_2;
	371	rt2->rt_hdr.segments_left = 1;
	372	memset(&rt2->reserved, 0, sizeof(rt2->reserved));
	373
	374	BUG_TRAP(rt2->rt_hdr.hdrlen == 2);
	375
	376	memcpy(&rt2->addr, &iph->daddr, sizeof(rt2->addr));
	377	memcpy(&iph->daddr, x->coaddr, sizeof(iph->daddr));
	378
	379	return 0;
	380	}
	381
	382	static int mip6_rthdr_offset(struct xfrm_state x, struct sk_buff skb,
	383	u8 **nexthdr)
	384	{
	385	u16 offset = sizeof(struct ipv6hdr);
	386	struct ipv6_opt_hdr exthdr = (struct ipv6_opt_hdr)(skb->nh.ipv6h + 1);
	387	unsigned int packet_len = skb->tail - skb->nh.raw;
	388	int found_rhdr = 0;
	389
	390	*nexthdr = &skb->nh.ipv6h->nexthdr;
	391
	392	while (offset + 1 <= packet_len) {
	393
	394	switch (**nexthdr) {
	395	case NEXTHDR_HOP:
	396	break;
	397	case NEXTHDR_ROUTING:
	398	if (offset + 3 <= packet_len) {
	399	struct ipv6_rt_hdr *rt;
	400	rt = (struct ipv6_rt_hdr *)(skb->nh.raw + offset);
	401	if (rt->type != 0)
	402	return offset;
	403	}
	404	found_rhdr = 1;
405	break;
406	case NEXTHDR_DEST:
407	if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
408	return offset;
409
410	if (found_rhdr)
411	return offset;
412
413	break;
414	default:
415	return offset;
416	}
417
418	offset += ipv6_optlen(exthdr);
419	*nexthdr = &exthdr->nexthdr;
420	exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
421	}
422
423	return offset;
424	}
425
426	static int mip6_rthdr_init_state(struct xfrm_state *x)
427	{
428	if (x->id.spi) {
429	printk(KERN_INFO "%s: spi is not 0: %u\n", __FUNCTION__,
430	x->id.spi);
431	return -EINVAL;
432	}
433	if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
434	printk(KERN_INFO "%s: state's mode is not %u: %u\n",
435	__FUNCTION__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
436	return -EINVAL;
437	}
438
439	x->props.header_len = sizeof(struct rt2_hdr);
440
441	return 0;
442	}
443
444	/*
445	* Do nothing about destroying since it has no specific operation for routing
446	* header type 2 unlike IPsec protocols.
447	*/
448	static void mip6_rthdr_destroy(struct xfrm_state *x)
449	{
450	}
451
452	static struct xfrm_type mip6_rthdr_type =
453	{
454	.description = "MIP6RT",
455	.owner = THIS_MODULE,
456	.proto = IPPROTO_ROUTING,
457	.flags = XFRM_TYPE_NON_FRAGMENT,
458	.init_state = mip6_rthdr_init_state,
459	.destructor = mip6_rthdr_destroy,
460	.input = mip6_rthdr_input,
461	.output = mip6_rthdr_output,
462	.hdr_offset = mip6_rthdr_offset,
463	.remote_addr = mip6_xfrm_addr,
464	};
465
466	int __init mip6_init(void)
467	{
468	printk(KERN_INFO "Mobile IPv6\n");
469
3d126890 NT	470	if (xfrm_register_type(&mip6_destopt_type, AF_INET6) < 0) {
	471	printk(KERN_INFO "%s: can't add xfrm type(destopt)\n", __FUNCTION__);
	472	goto mip6_destopt_xfrm_fail;
	473	}
2c8d7ca0 NT	474	if (xfrm_register_type(&mip6_rthdr_type, AF_INET6) < 0) {
	475	printk(KERN_INFO "%s: can't add xfrm type(rthdr)\n", __FUNCTION__);
	476	goto mip6_rthdr_xfrm_fail;
	477	}
	478	return 0;
	479
	480	mip6_rthdr_xfrm_fail:
3d126890 NT	481	xfrm_unregister_type(&mip6_destopt_type, AF_INET6);
3d126890 NT	482	mip6_destopt_xfrm_fail:
2c8d7ca0 NT	483	return -EAGAIN;
	484	}
	485
	486	void __exit mip6_fini(void)
	487	{
	488	if (xfrm_unregister_type(&mip6_rthdr_type, AF_INET6) < 0)
	489	printk(KERN_INFO "%s: can't remove xfrm type(rthdr)\n", __FUNCTION__);
3d126890 NT	490	if (xfrm_unregister_type(&mip6_destopt_type, AF_INET6) < 0)
3d126890 NT	491	printk(KERN_INFO "%s: can't remove xfrm type(destopt)\n", __FUNCTION__);
2c8d7ca0	492	}