[linux-2.6-block.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/config.h>
#include <linux/module.h>
#include <linux/skbuff.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 [%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x > %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x]\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;
}

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 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,
	.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
	25	#include <linux/config.h>
	26	#include <linux/module.h>
	27	#include <linux/skbuff.h>
	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))) {
	123	LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH checksum failed [%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x > %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x]\n",
	124	NIP6(skb->nh.ipv6h->saddr),
125	NIP6(skb->nh.ipv6h->daddr));
126	return -1;
127	}
128	skb->ip_summed = CHECKSUM_UNNECESSARY;
129	}
130
131	if (mh->ip6mh_proto != IPPROTO_NONE) {
132	LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH invalid payload proto = %d\n",
133	mh->ip6mh_proto);
134	mip6_param_prob(skb, 0, (&mh->ip6mh_proto) - skb->nh.raw);
135	return -1;
136	}
137
138	return 0;
139	}
140
3d126890 NT	141	static int mip6_destopt_input(struct xfrm_state x, struct sk_buff skb)
	142	{
	143	struct ipv6hdr *iph = skb->nh.ipv6h;
	144	struct ipv6_destopt_hdr destopt = (struct ipv6_destopt_hdr )skb->data;
	145
	146	if (!ipv6_addr_equal(&iph->saddr, (struct in6_addr *)x->coaddr) &&
	147	!ipv6_addr_any((struct in6_addr *)x->coaddr))
	148	return -ENOENT;
	149
	150	return destopt->nexthdr;
	151	}
	152
	153	/* Destination Option Header is inserted.
	154	* IP Header's src address is replaced with Home Address Option in
	155	* Destination Option Header.
	156	*/
	157	static int mip6_destopt_output(struct xfrm_state x, struct sk_buff skb)
	158	{
	159	struct ipv6hdr *iph;
	160	struct ipv6_destopt_hdr *dstopt;
	161	struct ipv6_destopt_hao *hao;
	162	u8 nexthdr;
	163	int len;
	164
	165	iph = (struct ipv6hdr *)skb->data;
	166	iph->payload_len = htons(skb->len - sizeof(*iph));
	167
	168	nexthdr = *skb->nh.raw;
	169	*skb->nh.raw = IPPROTO_DSTOPTS;
	170
	171	dstopt = (struct ipv6_destopt_hdr *)skb->h.raw;
	172	dstopt->nexthdr = nexthdr;
	173
	174	hao = mip6_padn((char *)(dstopt + 1),
	175	calc_padlen(sizeof(*dstopt), 6));
	176
	177	hao->type = IPV6_TLV_HAO;
	178	hao->length = sizeof(*hao) - 2;
	179	BUG_TRAP(hao->length == 16);
	180
	181	len = ((char )hao - (char )dstopt) + sizeof(*hao);
	182
	183	memcpy(&hao->addr, &iph->saddr, sizeof(hao->addr));
	184	memcpy(&iph->saddr, x->coaddr, sizeof(iph->saddr));
	185
	186	BUG_TRAP(len == x->props.header_len);
	187	dstopt->hdrlen = (x->props.header_len >> 3) - 1;
	188
	189	return 0;
	190	}
	191
	192	static int mip6_destopt_offset(struct xfrm_state x, struct sk_buff skb,
	193	u8 **nexthdr)
	194	{
	195	u16 offset = sizeof(struct ipv6hdr);
	196	struct ipv6_opt_hdr exthdr = (struct ipv6_opt_hdr)(skb->nh.ipv6h + 1);
	197	unsigned int packet_len = skb->tail - skb->nh.raw;
	198	int found_rhdr = 0;
	199
	200	*nexthdr = &skb->nh.ipv6h->nexthdr;
	201
	202	while (offset + 1 <= packet_len) {
	203
	204	switch (**nexthdr) {
205	case NEXTHDR_HOP:
206	break;
207	case NEXTHDR_ROUTING:
208	found_rhdr = 1;
209	break;
210	case NEXTHDR_DEST:
211	/*
212	* HAO MUST NOT appear more than once.
213	* XXX: It is better to try to find by the end of
214	* XXX: packet if HAO exists.
215	*/
216	if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) {
217	LIMIT_NETDEBUG(KERN_WARNING "mip6: hao exists already, override\n");
218	return offset;
219	}
220
221	if (found_rhdr)
222	return offset;
223
224	break;
225	default:
226	return offset;
227	}
228
229	offset += ipv6_optlen(exthdr);
230	*nexthdr = &exthdr->nexthdr;
231	exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
232	}
233
234	return offset;
235	}
236
237	static int mip6_destopt_init_state(struct xfrm_state *x)
238	{
239	if (x->id.spi) {
240	printk(KERN_INFO "%s: spi is not 0: %u\n", __FUNCTION__,
241	x->id.spi);
242	return -EINVAL;
243	}
244	if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
245	printk(KERN_INFO "%s: state's mode is not %u: %u\n",
246	__FUNCTION__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
247	return -EINVAL;
248	}
249
250	x->props.header_len = sizeof(struct ipv6_destopt_hdr) +
251	calc_padlen(sizeof(struct ipv6_destopt_hdr), 6) +
252	sizeof(struct ipv6_destopt_hao);
253	BUG_TRAP(x->props.header_len == 24);
254
255	return 0;
256	}
257
258	/*
259	* Do nothing about destroying since it has no specific operation for
260	* destination options header unlike IPsec protocols.
261	*/
262	static void mip6_destopt_destroy(struct xfrm_state *x)
263	{
264	}
265
266	static struct xfrm_type mip6_destopt_type =
267	{
268	.description = "MIP6DESTOPT",
269	.owner = THIS_MODULE,
270	.proto = IPPROTO_DSTOPTS,
271	.flags = XFRM_TYPE_NON_FRAGMENT,
272	.init_state = mip6_destopt_init_state,
273	.destructor = mip6_destopt_destroy,
274	.input = mip6_destopt_input,
275	.output = mip6_destopt_output,
276	.hdr_offset = mip6_destopt_offset,
277	.local_addr = mip6_xfrm_addr,
278	};
279
2c8d7ca0 NT	280	static int mip6_rthdr_input(struct xfrm_state x, struct sk_buff skb)
	281	{
	282	struct rt2_hdr rt2 = (struct rt2_hdr )skb->data;
	283
	284	if (!ipv6_addr_equal(&rt2->addr, (struct in6_addr *)x->coaddr) &&
	285	!ipv6_addr_any((struct in6_addr *)x->coaddr))
	286	return -ENOENT;
	287
	288	return rt2->rt_hdr.nexthdr;
	289	}
	290
	291	/* Routing Header type 2 is inserted.
	292	* IP Header's dst address is replaced with Routing Header's Home Address.
	293	*/
	294	static int mip6_rthdr_output(struct xfrm_state x, struct sk_buff skb)
	295	{
	296	struct ipv6hdr *iph;
	297	struct rt2_hdr *rt2;
	298	u8 nexthdr;
	299
	300	iph = (struct ipv6hdr *)skb->data;
	301	iph->payload_len = htons(skb->len - sizeof(*iph));
	302
	303	nexthdr = *skb->nh.raw;
	304	*skb->nh.raw = IPPROTO_ROUTING;
	305
	306	rt2 = (struct rt2_hdr *)skb->h.raw;
	307	rt2->rt_hdr.nexthdr = nexthdr;
	308	rt2->rt_hdr.hdrlen = (x->props.header_len >> 3) - 1;
	309	rt2->rt_hdr.type = IPV6_SRCRT_TYPE_2;
	310	rt2->rt_hdr.segments_left = 1;
	311	memset(&rt2->reserved, 0, sizeof(rt2->reserved));
	312
	313	BUG_TRAP(rt2->rt_hdr.hdrlen == 2);
	314
	315	memcpy(&rt2->addr, &iph->daddr, sizeof(rt2->addr));
	316	memcpy(&iph->daddr, x->coaddr, sizeof(iph->daddr));
	317
	318	return 0;
	319	}
	320
	321	static int mip6_rthdr_offset(struct xfrm_state x, struct sk_buff skb,
	322	u8 **nexthdr)
	323	{
	324	u16 offset = sizeof(struct ipv6hdr);
	325	struct ipv6_opt_hdr exthdr = (struct ipv6_opt_hdr)(skb->nh.ipv6h + 1);
	326	unsigned int packet_len = skb->tail - skb->nh.raw;
	327	int found_rhdr = 0;
	328
	329	*nexthdr = &skb->nh.ipv6h->nexthdr;
	330
	331	while (offset + 1 <= packet_len) {
	332
	333	switch (**nexthdr) {
	334	case NEXTHDR_HOP:
	335	break;
	336	case NEXTHDR_ROUTING:
	337	if (offset + 3 <= packet_len) {
	338	struct ipv6_rt_hdr *rt;
	339	rt = (struct ipv6_rt_hdr *)(skb->nh.raw + offset);
	340	if (rt->type != 0)
	341	return offset;
	342	}
	343	found_rhdr = 1;
344	break;
345	case NEXTHDR_DEST:
346	if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
347	return offset;
348
349	if (found_rhdr)
350	return offset;
351
352	break;
353	default:
354	return offset;
355	}
356
357	offset += ipv6_optlen(exthdr);
358	*nexthdr = &exthdr->nexthdr;
359	exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
360	}
361
362	return offset;
363	}
364
365	static int mip6_rthdr_init_state(struct xfrm_state *x)
366	{
367	if (x->id.spi) {
368	printk(KERN_INFO "%s: spi is not 0: %u\n", __FUNCTION__,
369	x->id.spi);
370	return -EINVAL;
371	}
372	if (x->props.mode != XFRM_MODE_ROUTEOPTIMIZATION) {
373	printk(KERN_INFO "%s: state's mode is not %u: %u\n",
374	__FUNCTION__, XFRM_MODE_ROUTEOPTIMIZATION, x->props.mode);
375	return -EINVAL;
376	}
377
378	x->props.header_len = sizeof(struct rt2_hdr);
379
380	return 0;
381	}
382
383	/*
384	* Do nothing about destroying since it has no specific operation for routing
385	* header type 2 unlike IPsec protocols.
386	*/
387	static void mip6_rthdr_destroy(struct xfrm_state *x)
388	{
389	}
390
391	static struct xfrm_type mip6_rthdr_type =
392	{
393	.description = "MIP6RT",
394	.owner = THIS_MODULE,
395	.proto = IPPROTO_ROUTING,
396	.flags = XFRM_TYPE_NON_FRAGMENT,
397	.init_state = mip6_rthdr_init_state,
398	.destructor = mip6_rthdr_destroy,
399	.input = mip6_rthdr_input,
400	.output = mip6_rthdr_output,
401	.hdr_offset = mip6_rthdr_offset,
402	.remote_addr = mip6_xfrm_addr,
403	};
404
405	int __init mip6_init(void)
406	{
407	printk(KERN_INFO "Mobile IPv6\n");
408
3d126890 NT	409	if (xfrm_register_type(&mip6_destopt_type, AF_INET6) < 0) {
	410	printk(KERN_INFO "%s: can't add xfrm type(destopt)\n", __FUNCTION__);
	411	goto mip6_destopt_xfrm_fail;
	412	}
2c8d7ca0 NT	413	if (xfrm_register_type(&mip6_rthdr_type, AF_INET6) < 0) {
	414	printk(KERN_INFO "%s: can't add xfrm type(rthdr)\n", __FUNCTION__);
	415	goto mip6_rthdr_xfrm_fail;
	416	}
	417	return 0;
	418
	419	mip6_rthdr_xfrm_fail:
3d126890 NT	420	xfrm_unregister_type(&mip6_destopt_type, AF_INET6);
3d126890 NT	421	mip6_destopt_xfrm_fail:
2c8d7ca0 NT	422	return -EAGAIN;
	423	}
	424
	425	void __exit mip6_fini(void)
	426	{
	427	if (xfrm_unregister_type(&mip6_rthdr_type, AF_INET6) < 0)
	428	printk(KERN_INFO "%s: can't remove xfrm type(rthdr)\n", __FUNCTION__);
3d126890 NT	429	if (xfrm_unregister_type(&mip6_destopt_type, AF_INET6) < 0)
3d126890 NT	430	printk(KERN_INFO "%s: can't remove xfrm type(destopt)\n", __FUNCTION__);
2c8d7ca0	431	}