[linux.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;
	int mhlen;

	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;
	}
	mhlen = (mh->ip6mh_hdrlen + 1) << 3;

	if (skb->ip_summed == CHECKSUM_COMPLETE) {
		skb->ip_summed = CHECKSUM_UNNECESSARY;
		if (csum_ipv6_magic(&skb->nh.ipv6h->saddr,
				    &skb->nh.ipv6h->daddr,
				    mhlen, IPPROTO_MH,
				    skb->csum)) {
			LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH hw checksum failed\n");
			skb->ip_summed = CHECKSUM_NONE;
		}
	}
	if (skb->ip_summed == CHECKSUM_NONE) {
		if (csum_ipv6_magic(&skb->nh.ipv6h->saddr,
				    &skb->nh.ipv6h->daddr,
				    mhlen, IPPROTO_MH,
				    skb_checksum(skb, 0, mhlen, 0))) {
			LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH checksum failed "
				       "[" NIP6_FMT " > " NIP6_FMT "]\n",
				       NIP6(skb->nh.ipv6h->saddr),
				       NIP6(skb->nh.ipv6h->daddr));
			return -1;
		}
		skb->ip_summed = CHECKSUM_UNNECESSARY;
	}

	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 = ~((__u16)0);
	sel.sport = xfrm_flowi_sport(fl);
	if (sel.sport)
		sel.sport_mask = ~((__u16)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;
	92	int mhlen;
	93
	94	if (!pskb_may_pull(skb, (skb->h.raw - skb->data) + 8) \|\|
	95	!pskb_may_pull(skb, (skb->h.raw - skb->data) + ((skb->h.raw[1] + 1) << 3)))
	96	return -1;
	97
	98	mh = (struct ip6_mh *)skb->h.raw;
	99
	100	if (mh->ip6mh_hdrlen < mip6_mh_len(mh->ip6mh_type)) {
	101	LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH message too short: %d vs >=%d\n",
	102	mh->ip6mh_hdrlen, mip6_mh_len(mh->ip6mh_type));
	103	mip6_param_prob(skb, 0, (&mh->ip6mh_hdrlen) - skb->nh.raw);
	104	return -1;
	105	}
	106	mhlen = (mh->ip6mh_hdrlen + 1) << 3;
	107
	108	if (skb->ip_summed == CHECKSUM_COMPLETE) {
	109	skb->ip_summed = CHECKSUM_UNNECESSARY;
	110	if (csum_ipv6_magic(&skb->nh.ipv6h->saddr,
	111	&skb->nh.ipv6h->daddr,
	112	mhlen, IPPROTO_MH,
	113	skb->csum)) {
	114	LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH hw checksum failed\n");
	115	skb->ip_summed = CHECKSUM_NONE;
	116	}
	117	}
	118	if (skb->ip_summed == CHECKSUM_NONE) {
	119	if (csum_ipv6_magic(&skb->nh.ipv6h->saddr,
	120	&skb->nh.ipv6h->daddr,
	121	mhlen, IPPROTO_MH,
	122	skb_checksum(skb, 0, mhlen, 0))) {
e731c248 YH	123	LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH checksum failed "
e731c248 YH	124	"[" NIP6_FMT " > " NIP6_FMT "]\n",
7be96f76 MN	125	NIP6(skb->nh.ipv6h->saddr),
	126	NIP6(skb->nh.ipv6h->daddr));
	127	return -1;
	128	}
	129	skb->ip_summed = CHECKSUM_UNNECESSARY;
	130	}
	131
	132	if (mh->ip6mh_proto != IPPROTO_NONE) {
	133	LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH invalid payload proto = %d\n",
	134	mh->ip6mh_proto);
	135	mip6_param_prob(skb, 0, (&mh->ip6mh_proto) - skb->nh.raw);
	136	return -1;
	137	}
	138
	139	return 0;
	140	}
	141
70182ed2 MN	142	struct mip6_report_rate_limiter {
	143	spinlock_t lock;
	144	struct timeval stamp;
	145	int iif;
	146	struct in6_addr src;
	147	struct in6_addr dst;
	148	};
	149
	150	static struct mip6_report_rate_limiter mip6_report_rl = {
	151	.lock = SPIN_LOCK_UNLOCKED
	152	};
	153
3d126890 NT	154	static int mip6_destopt_input(struct xfrm_state x, struct sk_buff skb)
	155	{
	156	struct ipv6hdr *iph = skb->nh.ipv6h;
	157	struct ipv6_destopt_hdr destopt = (struct ipv6_destopt_hdr )skb->data;
	158
	159	if (!ipv6_addr_equal(&iph->saddr, (struct in6_addr *)x->coaddr) &&
	160	!ipv6_addr_any((struct in6_addr *)x->coaddr))
	161	return -ENOENT;
	162
	163	return destopt->nexthdr;
	164	}
	165
	166	/* Destination Option Header is inserted.
	167	* IP Header's src address is replaced with Home Address Option in
	168	* Destination Option Header.
	169	*/
	170	static int mip6_destopt_output(struct xfrm_state x, struct sk_buff skb)
	171	{
	172	struct ipv6hdr *iph;
	173	struct ipv6_destopt_hdr *dstopt;
	174	struct ipv6_destopt_hao *hao;
	175	u8 nexthdr;
	176	int len;
	177
	178	iph = (struct ipv6hdr *)skb->data;
	179	iph->payload_len = htons(skb->len - sizeof(*iph));
	180
	181	nexthdr = *skb->nh.raw;
	182	*skb->nh.raw = IPPROTO_DSTOPTS;
	183
	184	dstopt = (struct ipv6_destopt_hdr *)skb->h.raw;
	185	dstopt->nexthdr = nexthdr;
	186
	187	hao = mip6_padn((char *)(dstopt + 1),
	188	calc_padlen(sizeof(*dstopt), 6));
	189
	190	hao->type = IPV6_TLV_HAO;
	191	hao->length = sizeof(*hao) - 2;
	192	BUG_TRAP(hao->length == 16);
	193
	194	len = ((char )hao - (char )dstopt) + sizeof(*hao);
	195
	196	memcpy(&hao->addr, &iph->saddr, sizeof(hao->addr));
	197	memcpy(&iph->saddr, x->coaddr, sizeof(iph->saddr));
	198
	199	BUG_TRAP(len == x->props.header_len);
	200	dstopt->hdrlen = (x->props.header_len >> 3) - 1;
	201
	202	return 0;
	203	}
	204
70182ed2 MN	205	static inline int mip6_report_rl_allow(struct timeval *stamp,
	206	struct in6_addr *dst,
	207	struct in6_addr *src, int iif)
	208	{
	209	int allow = 0;
	210
	211	spin_lock_bh(&mip6_report_rl.lock);
	212	if (mip6_report_rl.stamp.tv_sec != stamp->tv_sec \|\|
	213	mip6_report_rl.stamp.tv_usec != stamp->tv_usec \|\|
	214	mip6_report_rl.iif != iif \|\|
	215	!ipv6_addr_equal(&mip6_report_rl.src, src) \|\|
	216	!ipv6_addr_equal(&mip6_report_rl.dst, dst)) {
	217	mip6_report_rl.stamp.tv_sec = stamp->tv_sec;
	218	mip6_report_rl.stamp.tv_usec = stamp->tv_usec;
	219	mip6_report_rl.iif = iif;
	220	ipv6_addr_copy(&mip6_report_rl.src, src);
	221	ipv6_addr_copy(&mip6_report_rl.dst, dst);
	222	allow = 1;
	223	}
	224	spin_unlock_bh(&mip6_report_rl.lock);
	225	return allow;
	226	}
	227
	228	static int mip6_destopt_reject(struct xfrm_state x, struct sk_buff skb, struct flowi *fl)
	229	{
	230	struct inet6_skb_parm opt = (struct inet6_skb_parm )skb->cb;
	231	struct ipv6_destopt_hao *hao = NULL;
	232	struct xfrm_selector sel;
	233	int offset;
	234	struct timeval stamp;
	235	int err = 0;
	236
e731c248 YH	237	if (unlikely(fl->proto == IPPROTO_MH &&
e731c248 YH	238	fl->fl_mh_type <= IP6_MH_TYPE_MAX))
01be8e5d MN	239	goto out;
01be8e5d MN	240
70182ed2 MN	241	if (likely(opt->dsthao)) {
	242	offset = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
	243	if (likely(offset >= 0))
	244	hao = (struct ipv6_destopt_hao *)(skb->nh.raw + offset);
	245	}
	246
	247	skb_get_timestamp(skb, &stamp);
	248
	249	if (!mip6_report_rl_allow(&stamp, &skb->nh.ipv6h->daddr,
	250	hao ? &hao->addr : &skb->nh.ipv6h->saddr,
	251	opt->iif))
	252	goto out;
	253
	254	memset(&sel, 0, sizeof(sel));
	255	memcpy(&sel.daddr, (xfrm_address_t *)&skb->nh.ipv6h->daddr,
	256	sizeof(sel.daddr));
	257	sel.prefixlen_d = 128;
	258	memcpy(&sel.saddr, (xfrm_address_t *)&skb->nh.ipv6h->saddr,
	259	sizeof(sel.saddr));
	260	sel.prefixlen_s = 128;
	261	sel.family = AF_INET6;
	262	sel.proto = fl->proto;
	263	sel.dport = xfrm_flowi_dport(fl);
	264	if (sel.dport)
	265	sel.dport_mask = ~((__u16)0);
	266	sel.sport = xfrm_flowi_sport(fl);
	267	if (sel.sport)
	268	sel.sport_mask = ~((__u16)0);
	269	sel.ifindex = fl->oif;
	270
	271	err = km_report(IPPROTO_DSTOPTS, &sel,
	272	(hao ? (xfrm_address_t *)&hao->addr : NULL));
	273
	274	out:
	275	return err;
	276	}
	277
3d126890 NT	278	static int mip6_destopt_offset(struct xfrm_state x, struct sk_buff skb,
	279	u8 **nexthdr)
	280	{
	281	u16 offset = sizeof(struct ipv6hdr);
	282	struct ipv6_opt_hdr exthdr = (struct ipv6_opt_hdr)(skb->nh.ipv6h + 1);
	283	unsigned int packet_len = skb->tail - skb->nh.raw;
	284	int found_rhdr = 0;
	285
	286	*nexthdr = &skb->nh.ipv6h->nexthdr;
	287
	288	while (offset + 1 <= packet_len) {
	289
	290	switch (**nexthdr) {
	291	case NEXTHDR_HOP:
	292	break;
	293	case NEXTHDR_ROUTING:
	294	found_rhdr = 1;
	295	break;
	296	case NEXTHDR_DEST:
	297	/*
	298	* HAO MUST NOT appear more than once.
	299	* XXX: It is better to try to find by the end of
	300	* XXX: packet if HAO exists.
	301	*/
	302	if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) {
	303	LIMIT_NETDEBUG(KERN_WARNING "mip6: hao exists already, override\n");
	304	return offset;
	305	}
	306
	307	if (found_rhdr)
	308	return offset;
	309
	310	break;
	311	default:
	312	return offset;
	313	}
	314
	315	offset += ipv6_optlen(exthdr);
	316	*nexthdr = &exthdr->nexthdr;
	317	exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
	318	}
	319
	320	return offset;
	321	}
	322
	323	static int mip6_destopt_init_state(struct xfrm_state *x)
	324	{
	325	if (x->id.spi) {
	326	printk(KERN_INFO "%s: spi is not 0: %u\n", __FUNCTION__,
	327	x->id.spi);
	328	return -EINVAL;
	329	}
	330	if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
	331	printk(KERN_INFO "%s: state's mode is not %u: %u\n",
	332	__FUNCTION__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
	333	return -EINVAL;
	334	}
	335
	336	x->props.header_len = sizeof(struct ipv6_destopt_hdr) +
	337	calc_padlen(sizeof(struct ipv6_destopt_hdr), 6) +
	338	sizeof(struct ipv6_destopt_hao);
	339	BUG_TRAP(x->props.header_len == 24);
	340
	341	return 0;
342	}
343
344	/*
345	* Do nothing about destroying since it has no specific operation for
346	* destination options header unlike IPsec protocols.
347	*/
348	static void mip6_destopt_destroy(struct xfrm_state *x)
349	{
350	}
351
352	static struct xfrm_type mip6_destopt_type =
353	{
354	.description = "MIP6DESTOPT",
355	.owner = THIS_MODULE,
356	.proto = IPPROTO_DSTOPTS,
357	.flags = XFRM_TYPE_NON_FRAGMENT,
358	.init_state = mip6_destopt_init_state,
359	.destructor = mip6_destopt_destroy,
360	.input = mip6_destopt_input,
361	.output = mip6_destopt_output,
70182ed2	362	.reject = mip6_destopt_reject,
3d126890 NT	363	.hdr_offset = mip6_destopt_offset,
	364	.local_addr = mip6_xfrm_addr,
	365	};
	366
2c8d7ca0 NT	367	static int mip6_rthdr_input(struct xfrm_state x, struct sk_buff skb)
	368	{
	369	struct rt2_hdr rt2 = (struct rt2_hdr )skb->data;
	370
	371	if (!ipv6_addr_equal(&rt2->addr, (struct in6_addr *)x->coaddr) &&
	372	!ipv6_addr_any((struct in6_addr *)x->coaddr))
	373	return -ENOENT;
	374
	375	return rt2->rt_hdr.nexthdr;
	376	}
	377
	378	/* Routing Header type 2 is inserted.
	379	* IP Header's dst address is replaced with Routing Header's Home Address.
	380	*/
	381	static int mip6_rthdr_output(struct xfrm_state x, struct sk_buff skb)
	382	{
	383	struct ipv6hdr *iph;
	384	struct rt2_hdr *rt2;
	385	u8 nexthdr;
	386
	387	iph = (struct ipv6hdr *)skb->data;
	388	iph->payload_len = htons(skb->len - sizeof(*iph));
	389
	390	nexthdr = *skb->nh.raw;
	391	*skb->nh.raw = IPPROTO_ROUTING;
	392
	393	rt2 = (struct rt2_hdr *)skb->h.raw;
	394	rt2->rt_hdr.nexthdr = nexthdr;
	395	rt2->rt_hdr.hdrlen = (x->props.header_len >> 3) - 1;
	396	rt2->rt_hdr.type = IPV6_SRCRT_TYPE_2;
	397	rt2->rt_hdr.segments_left = 1;
	398	memset(&rt2->reserved, 0, sizeof(rt2->reserved));
	399
	400	BUG_TRAP(rt2->rt_hdr.hdrlen == 2);
	401
	402	memcpy(&rt2->addr, &iph->daddr, sizeof(rt2->addr));
	403	memcpy(&iph->daddr, x->coaddr, sizeof(iph->daddr));
	404
	405	return 0;
	406	}
	407
	408	static int mip6_rthdr_offset(struct xfrm_state x, struct sk_buff skb,
	409	u8 **nexthdr)
	410	{
	411	u16 offset = sizeof(struct ipv6hdr);
	412	struct ipv6_opt_hdr exthdr = (struct ipv6_opt_hdr)(skb->nh.ipv6h + 1);
	413	unsigned int packet_len = skb->tail - skb->nh.raw;
	414	int found_rhdr = 0;
	415
	416	*nexthdr = &skb->nh.ipv6h->nexthdr;
	417
	418	while (offset + 1 <= packet_len) {
	419
	420	switch (**nexthdr) {
	421	case NEXTHDR_HOP:
	422	break;
	423	case NEXTHDR_ROUTING:
	424	if (offset + 3 <= packet_len) {
	425	struct ipv6_rt_hdr *rt;
	426	rt = (struct ipv6_rt_hdr *)(skb->nh.raw + offset);
	427	if (rt->type != 0)
	428	return offset;
	429	}
	430	found_rhdr = 1;
431	break;
432	case NEXTHDR_DEST:
433	if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
434	return offset;
435
436	if (found_rhdr)
437	return offset;
438
439	break;
440	default:
441	return offset;
442	}
443
444	offset += ipv6_optlen(exthdr);
445	*nexthdr = &exthdr->nexthdr;
446	exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
447	}
448
449	return offset;
450	}
451
452	static int mip6_rthdr_init_state(struct xfrm_state *x)
453	{
454	if (x->id.spi) {
455	printk(KERN_INFO "%s: spi is not 0: %u\n", __FUNCTION__,
456	x->id.spi);
457	return -EINVAL;
458	}
459	if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
460	printk(KERN_INFO "%s: state's mode is not %u: %u\n",
461	__FUNCTION__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
462	return -EINVAL;
463	}
464
465	x->props.header_len = sizeof(struct rt2_hdr);
466
467	return 0;
468	}
469
470	/*
471	* Do nothing about destroying since it has no specific operation for routing
472	* header type 2 unlike IPsec protocols.
473	*/
474	static void mip6_rthdr_destroy(struct xfrm_state *x)
475	{
476	}
477
478	static struct xfrm_type mip6_rthdr_type =
479	{
480	.description = "MIP6RT",
481	.owner = THIS_MODULE,
482	.proto = IPPROTO_ROUTING,
483	.flags = XFRM_TYPE_NON_FRAGMENT,
484	.init_state = mip6_rthdr_init_state,
485	.destructor = mip6_rthdr_destroy,
486	.input = mip6_rthdr_input,
487	.output = mip6_rthdr_output,
488	.hdr_offset = mip6_rthdr_offset,
489	.remote_addr = mip6_xfrm_addr,
490	};
491
492	int __init mip6_init(void)
493	{
494	printk(KERN_INFO "Mobile IPv6\n");
495
3d126890 NT	496	if (xfrm_register_type(&mip6_destopt_type, AF_INET6) < 0) {
	497	printk(KERN_INFO "%s: can't add xfrm type(destopt)\n", __FUNCTION__);
	498	goto mip6_destopt_xfrm_fail;
	499	}
2c8d7ca0 NT	500	if (xfrm_register_type(&mip6_rthdr_type, AF_INET6) < 0) {
	501	printk(KERN_INFO "%s: can't add xfrm type(rthdr)\n", __FUNCTION__);
	502	goto mip6_rthdr_xfrm_fail;
	503	}
	504	return 0;
	505
	506	mip6_rthdr_xfrm_fail:
3d126890 NT	507	xfrm_unregister_type(&mip6_destopt_type, AF_INET6);
3d126890 NT	508	mip6_destopt_xfrm_fail:
2c8d7ca0 NT	509	return -EAGAIN;
	510	}
	511
	512	void __exit mip6_fini(void)
	513	{
	514	if (xfrm_unregister_type(&mip6_rthdr_type, AF_INET6) < 0)
	515	printk(KERN_INFO "%s: can't remove xfrm type(rthdr)\n", __FUNCTION__);
3d126890 NT	516	if (xfrm_unregister_type(&mip6_destopt_type, AF_INET6) < 0)
3d126890 NT	517	printk(KERN_INFO "%s: can't remove xfrm type(destopt)\n", __FUNCTION__);
2c8d7ca0	518	}