[mirror_ubuntu-artful-kernel.git] / net / ipv6 / xfrm6_policy.c

/*
 * xfrm6_policy.c: based on xfrm4_policy.c
 *
 * Authors:
 *	Mitsuru KANDA @USAGI
 * 	Kazunori MIYAZAWA @USAGI
 * 	Kunihiro Ishiguro <kunihiro@ipinfusion.com>
 * 		IPv6 support
 * 	YOSHIFUJI Hideaki
 * 		Split up af-specific portion
 *
 */

#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <net/addrconf.h>
#include <net/dst.h>
#include <net/xfrm.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <net/ip6_route.h>
#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
#include <net/mip6.h>
#endif

static struct dst_ops xfrm6_dst_ops;
static struct xfrm_policy_afinfo xfrm6_policy_afinfo;

static struct dst_entry *xfrm6_dst_lookup(int tos, xfrm_address_t *saddr,
					  xfrm_address_t *daddr)
{
	struct flowi fl = {};
	struct dst_entry *dst;
	int err;

	memcpy(&fl.fl6_dst, daddr, sizeof(fl.fl6_dst));
	if (saddr)
		memcpy(&fl.fl6_src, saddr, sizeof(fl.fl6_src));

	dst = ip6_route_output(NULL, &fl);

	err = dst->error;
	if (dst->error) {
		dst_release(dst);
		dst = ERR_PTR(err);
	}

	return dst;
}

static int xfrm6_get_saddr(xfrm_address_t *saddr, xfrm_address_t *daddr)
{
	struct dst_entry *dst;

	dst = xfrm6_dst_lookup(0, NULL, daddr);
	if (IS_ERR(dst))
		return -EHOSTUNREACH;

	ipv6_get_saddr(dst, (struct in6_addr *)&daddr->a6,
		       (struct in6_addr *)&saddr->a6);
	dst_release(dst);
	return 0;
}

static struct dst_entry *
__xfrm6_find_bundle(struct flowi *fl, struct xfrm_policy *policy)
{
	struct dst_entry *dst;

	/* Still not clear if we should set fl->fl6_{src,dst}... */
	read_lock_bh(&policy->lock);
	for (dst = policy->bundles; dst; dst = dst->next) {
		struct xfrm_dst *xdst = (struct xfrm_dst*)dst;
		struct in6_addr fl_dst_prefix, fl_src_prefix;

		ipv6_addr_prefix(&fl_dst_prefix,
				 &fl->fl6_dst,
				 xdst->u.rt6.rt6i_dst.plen);
		ipv6_addr_prefix(&fl_src_prefix,
				 &fl->fl6_src,
				 xdst->u.rt6.rt6i_src.plen);
		if (ipv6_addr_equal(&xdst->u.rt6.rt6i_dst.addr, &fl_dst_prefix) &&
		    ipv6_addr_equal(&xdst->u.rt6.rt6i_src.addr, &fl_src_prefix) &&
		    xfrm_bundle_ok(policy, xdst, fl, AF_INET6,
				   (xdst->u.rt6.rt6i_dst.plen != 128 ||
				    xdst->u.rt6.rt6i_src.plen != 128))) {
			dst_clone(dst);
			break;
		}
	}
	read_unlock_bh(&policy->lock);
	return dst;
}

static int xfrm6_get_tos(struct flowi *fl)
{
	return 0;
}

static int xfrm6_fill_dst(struct xfrm_dst *xdst, struct net_device *dev)
{
	struct rt6_info *rt = (struct rt6_info*)xdst->route;

	xdst->u.dst.dev = dev;
	dev_hold(dev);

	xdst->u.rt6.rt6i_idev = in6_dev_get(rt->u.dst.dev);
	if (!xdst->u.rt6.rt6i_idev)
		return -ENODEV;

	/* Sheit... I remember I did this right. Apparently,
	 * it was magically lost, so this code needs audit */
	xdst->u.rt6.rt6i_flags = rt->rt6i_flags & (RTF_ANYCAST |
						   RTF_LOCAL);
	xdst->u.rt6.rt6i_metric = rt->rt6i_metric;
	xdst->u.rt6.rt6i_node = rt->rt6i_node;
	xdst->u.rt6.rt6i_gateway = rt->rt6i_gateway;
	xdst->u.rt6.rt6i_dst = rt->rt6i_dst;
	xdst->u.rt6.rt6i_src = rt->rt6i_src;

	return 0;
}

static inline void
_decode_session6(struct sk_buff *skb, struct flowi *fl)
{
	u16 offset = skb_network_header_len(skb);
	struct ipv6hdr *hdr = ipv6_hdr(skb);
	struct ipv6_opt_hdr *exthdr;
	const unsigned char *nh = skb_network_header(skb);
	u8 nexthdr = nh[IP6CB(skb)->nhoff];

	memset(fl, 0, sizeof(struct flowi));
	ipv6_addr_copy(&fl->fl6_dst, &hdr->daddr);
	ipv6_addr_copy(&fl->fl6_src, &hdr->saddr);

	while (pskb_may_pull(skb, nh + offset + 1 - skb->data)) {
		nh = skb_network_header(skb);
		exthdr = (struct ipv6_opt_hdr *)(nh + offset);

		switch (nexthdr) {
		case NEXTHDR_ROUTING:
		case NEXTHDR_HOP:
		case NEXTHDR_DEST:
			offset += ipv6_optlen(exthdr);
			nexthdr = exthdr->nexthdr;
			exthdr = (struct ipv6_opt_hdr *)(nh + offset);
			break;

		case IPPROTO_UDP:
		case IPPROTO_UDPLITE:
		case IPPROTO_TCP:
		case IPPROTO_SCTP:
		case IPPROTO_DCCP:
			if (pskb_may_pull(skb, nh + offset + 4 - skb->data)) {
				__be16 *ports = (__be16 *)exthdr;

				fl->fl_ip_sport = ports[0];
				fl->fl_ip_dport = ports[1];
			}
			fl->proto = nexthdr;
			return;

		case IPPROTO_ICMPV6:
			if (pskb_may_pull(skb, nh + offset + 2 - skb->data)) {
				u8 *icmp = (u8 *)exthdr;

				fl->fl_icmp_type = icmp[0];
				fl->fl_icmp_code = icmp[1];
			}
			fl->proto = nexthdr;
			return;

#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
		case IPPROTO_MH:
			if (pskb_may_pull(skb, nh + offset + 3 - skb->data)) {
				struct ip6_mh *mh;
				mh = (struct ip6_mh *)exthdr;

				fl->fl_mh_type = mh->ip6mh_type;
			}
			fl->proto = nexthdr;
			return;
#endif

		/* XXX Why are there these headers? */
		case IPPROTO_AH:
		case IPPROTO_ESP:
		case IPPROTO_COMP:
		default:
			fl->fl_ipsec_spi = 0;
			fl->proto = nexthdr;
			return;
		}
	}
}

static inline int xfrm6_garbage_collect(void)
{
	xfrm6_policy_afinfo.garbage_collect();
	return (atomic_read(&xfrm6_dst_ops.entries) > xfrm6_dst_ops.gc_thresh*2);
}

static void xfrm6_update_pmtu(struct dst_entry *dst, u32 mtu)
{
	struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
	struct dst_entry *path = xdst->route;

	path->ops->update_pmtu(path, mtu);
}

static void xfrm6_dst_destroy(struct dst_entry *dst)
{
	struct xfrm_dst *xdst = (struct xfrm_dst *)dst;

	if (likely(xdst->u.rt6.rt6i_idev))
		in6_dev_put(xdst->u.rt6.rt6i_idev);
	xfrm_dst_destroy(xdst);
}

static void xfrm6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
			     int unregister)
{
	struct xfrm_dst *xdst;

	if (!unregister)
		return;

	xdst = (struct xfrm_dst *)dst;
	if (xdst->u.rt6.rt6i_idev->dev == dev) {
		struct inet6_dev *loopback_idev =
			in6_dev_get(dev->nd_net->loopback_dev);
		BUG_ON(!loopback_idev);

		do {
			in6_dev_put(xdst->u.rt6.rt6i_idev);
			xdst->u.rt6.rt6i_idev = loopback_idev;
			in6_dev_hold(loopback_idev);
			xdst = (struct xfrm_dst *)xdst->u.dst.child;
		} while (xdst->u.dst.xfrm);

		__in6_dev_put(loopback_idev);
	}

	xfrm_dst_ifdown(dst, dev);
}

static struct dst_ops xfrm6_dst_ops = {
	.family =		AF_INET6,
	.protocol =		__constant_htons(ETH_P_IPV6),
	.gc =			xfrm6_garbage_collect,
	.update_pmtu =		xfrm6_update_pmtu,
	.destroy =		xfrm6_dst_destroy,
	.ifdown =		xfrm6_dst_ifdown,
	.local_out =		__ip6_local_out,
	.gc_thresh =		1024,
	.entry_size =		sizeof(struct xfrm_dst),
};

static struct xfrm_policy_afinfo xfrm6_policy_afinfo = {
	.family =		AF_INET6,
	.dst_ops =		&xfrm6_dst_ops,
	.dst_lookup =		xfrm6_dst_lookup,
	.get_saddr = 		xfrm6_get_saddr,
	.find_bundle =		__xfrm6_find_bundle,
	.decode_session =	_decode_session6,
	.get_tos =		xfrm6_get_tos,
	.fill_dst =		xfrm6_fill_dst,
};

static void __init xfrm6_policy_init(void)
{
	xfrm_policy_register_afinfo(&xfrm6_policy_afinfo);
}

static void xfrm6_policy_fini(void)
{
	xfrm_policy_unregister_afinfo(&xfrm6_policy_afinfo);
}

void __init xfrm6_init(void)
{
	xfrm6_policy_init();
	xfrm6_state_init();
}

void xfrm6_fini(void)
{
	//xfrm6_input_fini();
	xfrm6_policy_fini();
	xfrm6_state_fini();
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* xfrm6_policy.c: based on xfrm4_policy.c
	3	*
	4	* Authors:
	5	* Mitsuru KANDA @USAGI
	6	* Kazunori MIYAZAWA @USAGI
	7	* Kunihiro Ishiguro <kunihiro@ipinfusion.com>
	8	* IPv6 support
	9	* YOSHIFUJI Hideaki
	10	* Split up af-specific portion
1ab1457c	11	*
1da177e4 LT	12	*/
1da177e4 LT	13
66cdb3ca HX	14	#include <linux/err.h>
66cdb3ca HX	15	#include <linux/kernel.h>
aabc9761 HX	16	#include <linux/netdevice.h>
aabc9761 HX	17	#include <net/addrconf.h>
45ff5a3f	18	#include <net/dst.h>
1da177e4 LT	19	#include <net/xfrm.h>
	20	#include <net/ip.h>
	21	#include <net/ipv6.h>
	22	#include <net/ip6_route.h>
59fbb3a6	23	#if defined(CONFIG_IPV6_MIP6) \|\| defined(CONFIG_IPV6_MIP6_MODULE)
2ce4272a MN	24	#include <net/mip6.h>
2ce4272a MN	25	#endif
1da177e4 LT	26
	27	static struct dst_ops xfrm6_dst_ops;
	28	static struct xfrm_policy_afinfo xfrm6_policy_afinfo;
	29
66cdb3ca HX	30	static struct dst_entry xfrm6_dst_lookup(int tos, xfrm_address_t saddr,
66cdb3ca HX	31	xfrm_address_t *daddr)
1da177e4	32	{
66cdb3ca HX	33	struct flowi fl = {};
	34	struct dst_entry *dst;
	35	int err;
	36
	37	memcpy(&fl.fl6_dst, daddr, sizeof(fl.fl6_dst));
	38	if (saddr)
	39	memcpy(&fl.fl6_src, saddr, sizeof(fl.fl6_src));
	40
	41	dst = ip6_route_output(NULL, &fl);
	42
	43	err = dst->error;
	44	if (dst->error) {
4251320f	45	dst_release(dst);
66cdb3ca HX	46	dst = ERR_PTR(err);
	47	}
	48
	49	return dst;
1da177e4 LT	50	}
1da177e4 LT	51
a1e59abf PM	52	static int xfrm6_get_saddr(xfrm_address_t saddr, xfrm_address_t daddr)
a1e59abf PM	53	{
66cdb3ca HX	54	struct dst_entry *dst;
	55
	56	dst = xfrm6_dst_lookup(0, NULL, daddr);
	57	if (IS_ERR(dst))
	58	return -EHOSTUNREACH;
	59
	60	ipv6_get_saddr(dst, (struct in6_addr *)&daddr->a6,
	61	(struct in6_addr *)&saddr->a6);
	62	dst_release(dst);
	63	return 0;
a1e59abf PM	64	}
a1e59abf PM	65
1da177e4 LT	66	static struct dst_entry *
	67	__xfrm6_find_bundle(struct flowi fl, struct xfrm_policy policy)
	68	{
	69	struct dst_entry *dst;
	70
	71	/* Still not clear if we should set fl->fl6_{src,dst}... */
	72	read_lock_bh(&policy->lock);
	73	for (dst = policy->bundles; dst; dst = dst->next) {
	74	struct xfrm_dst xdst = (struct xfrm_dst)dst;
	75	struct in6_addr fl_dst_prefix, fl_src_prefix;
	76
	77	ipv6_addr_prefix(&fl_dst_prefix,
	78	&fl->fl6_dst,
	79	xdst->u.rt6.rt6i_dst.plen);
	80	ipv6_addr_prefix(&fl_src_prefix,
	81	&fl->fl6_src,
	82	xdst->u.rt6.rt6i_src.plen);
	83	if (ipv6_addr_equal(&xdst->u.rt6.rt6i_dst.addr, &fl_dst_prefix) &&
	84	ipv6_addr_equal(&xdst->u.rt6.rt6i_src.addr, &fl_src_prefix) &&
5b368e61	85	xfrm_bundle_ok(policy, xdst, fl, AF_INET6,
e53820de MN	86	(xdst->u.rt6.rt6i_dst.plen != 128 \|\|
e53820de MN	87	xdst->u.rt6.rt6i_src.plen != 128))) {
1da177e4 LT	88	dst_clone(dst);
	89	break;
	90	}
	91	}
	92	read_unlock_bh(&policy->lock);
	93	return dst;
	94	}
	95
25ee3286	96	static int xfrm6_get_tos(struct flowi *fl)
1da177e4	97	{
25ee3286 HX	98	return 0;
25ee3286 HX	99	}
1da177e4	100
25ee3286 HX	101	static int xfrm6_fill_dst(struct xfrm_dst xdst, struct net_device dev)
	102	{
	103	struct rt6_info rt = (struct rt6_info)xdst->route;
1da177e4	104
25ee3286 HX	105	xdst->u.dst.dev = dev;
25ee3286 HX	106	dev_hold(dev);
1da177e4	107
25ee3286 HX	108	xdst->u.rt6.rt6i_idev = in6_dev_get(rt->u.dst.dev);
	109	if (!xdst->u.rt6.rt6i_idev)
	110	return -ENODEV;
1da177e4	111
25ee3286 HX	112	/* Sheit... I remember I did this right. Apparently,
	113	* it was magically lost, so this code needs audit */
	114	xdst->u.rt6.rt6i_flags = rt->rt6i_flags & (RTF_ANYCAST \|
	115	RTF_LOCAL);
	116	xdst->u.rt6.rt6i_metric = rt->rt6i_metric;
	117	xdst->u.rt6.rt6i_node = rt->rt6i_node;
	118	xdst->u.rt6.rt6i_gateway = rt->rt6i_gateway;
	119	xdst->u.rt6.rt6i_dst = rt->rt6i_dst;
	120	xdst->u.rt6.rt6i_src = rt->rt6i_src;
1da177e4	121
1da177e4	122	return 0;
1da177e4 LT	123	}
	124
	125	static inline void
	126	_decode_session6(struct sk_buff skb, struct flowi fl)
	127	{
cfe1fc77	128	u16 offset = skb_network_header_len(skb);
0660e03f	129	struct ipv6hdr *hdr = ipv6_hdr(skb);
e3cae904	130	struct ipv6_opt_hdr *exthdr;
d56f90a7 ACM	131	const unsigned char *nh = skb_network_header(skb);
d56f90a7 ACM	132	u8 nexthdr = nh[IP6CB(skb)->nhoff];
1da177e4 LT	133
	134	memset(fl, 0, sizeof(struct flowi));
	135	ipv6_addr_copy(&fl->fl6_dst, &hdr->daddr);
	136	ipv6_addr_copy(&fl->fl6_src, &hdr->saddr);
	137
d56f90a7 ACM	138	while (pskb_may_pull(skb, nh + offset + 1 - skb->data)) {
	139	nh = skb_network_header(skb);
	140	exthdr = (struct ipv6_opt_hdr *)(nh + offset);
e3cae904	141
1da177e4 LT	142	switch (nexthdr) {
	143	case NEXTHDR_ROUTING:
	144	case NEXTHDR_HOP:
	145	case NEXTHDR_DEST:
	146	offset += ipv6_optlen(exthdr);
	147	nexthdr = exthdr->nexthdr;
d56f90a7	148	exthdr = (struct ipv6_opt_hdr *)(nh + offset);
1da177e4 LT	149	break;
	150
	151	case IPPROTO_UDP:
ba4e58ec	152	case IPPROTO_UDPLITE:
1da177e4 LT	153	case IPPROTO_TCP:
1da177e4 LT	154	case IPPROTO_SCTP:
9e999993	155	case IPPROTO_DCCP:
d56f90a7	156	if (pskb_may_pull(skb, nh + offset + 4 - skb->data)) {
8c689a6e	157	__be16 ports = (__be16 )exthdr;
1da177e4 LT	158
	159	fl->fl_ip_sport = ports[0];
	160	fl->fl_ip_dport = ports[1];
	161	}
	162	fl->proto = nexthdr;
	163	return;
	164
	165	case IPPROTO_ICMPV6:
d56f90a7	166	if (pskb_may_pull(skb, nh + offset + 2 - skb->data)) {
1da177e4 LT	167	u8 icmp = (u8 )exthdr;
	168
	169	fl->fl_icmp_type = icmp[0];
	170	fl->fl_icmp_code = icmp[1];
	171	}
	172	fl->proto = nexthdr;
	173	return;
	174
59fbb3a6	175	#if defined(CONFIG_IPV6_MIP6) \|\| defined(CONFIG_IPV6_MIP6_MODULE)
2ce4272a	176	case IPPROTO_MH:
d56f90a7	177	if (pskb_may_pull(skb, nh + offset + 3 - skb->data)) {
2ce4272a MN	178	struct ip6_mh *mh;
	179	mh = (struct ip6_mh *)exthdr;
	180
	181	fl->fl_mh_type = mh->ip6mh_type;
	182	}
	183	fl->proto = nexthdr;
	184	return;
	185	#endif
	186
1da177e4 LT	187	/* XXX Why are there these headers? */
	188	case IPPROTO_AH:
	189	case IPPROTO_ESP:
	190	case IPPROTO_COMP:
	191	default:
	192	fl->fl_ipsec_spi = 0;
	193	fl->proto = nexthdr;
	194	return;
3ff50b79	195	}
1da177e4 LT	196	}
	197	}
	198
	199	static inline int xfrm6_garbage_collect(void)
	200	{
1da177e4	201	xfrm6_policy_afinfo.garbage_collect();
1da177e4 LT	202	return (atomic_read(&xfrm6_dst_ops.entries) > xfrm6_dst_ops.gc_thresh*2);
	203	}
	204
	205	static void xfrm6_update_pmtu(struct dst_entry *dst, u32 mtu)
	206	{
	207	struct xfrm_dst xdst = (struct xfrm_dst )dst;
	208	struct dst_entry *path = xdst->route;
	209
	210	path->ops->update_pmtu(path, mtu);
	211	}
	212
aabc9761 HX	213	static void xfrm6_dst_destroy(struct dst_entry *dst)
	214	{
	215	struct xfrm_dst xdst = (struct xfrm_dst )dst;
	216
	217	if (likely(xdst->u.rt6.rt6i_idev))
	218	in6_dev_put(xdst->u.rt6.rt6i_idev);
	219	xfrm_dst_destroy(xdst);
	220	}
	221
	222	static void xfrm6_dst_ifdown(struct dst_entry dst, struct net_device dev,
	223	int unregister)
	224	{
	225	struct xfrm_dst *xdst;
	226
	227	if (!unregister)
	228	return;
	229
	230	xdst = (struct xfrm_dst *)dst;
	231	if (xdst->u.rt6.rt6i_idev->dev == dev) {
5a3e55d6 DL	232	struct inet6_dev *loopback_idev =
5a3e55d6 DL	233	in6_dev_get(dev->nd_net->loopback_dev);
aabc9761 HX	234	BUG_ON(!loopback_idev);
	235
	236	do {
	237	in6_dev_put(xdst->u.rt6.rt6i_idev);
	238	xdst->u.rt6.rt6i_idev = loopback_idev;
	239	in6_dev_hold(loopback_idev);
	240	xdst = (struct xfrm_dst *)xdst->u.dst.child;
	241	} while (xdst->u.dst.xfrm);
	242
	243	__in6_dev_put(loopback_idev);
	244	}
	245
	246	xfrm_dst_ifdown(dst, dev);
	247	}
	248
1da177e4 LT	249	static struct dst_ops xfrm6_dst_ops = {
	250	.family = AF_INET6,
	251	.protocol = __constant_htons(ETH_P_IPV6),
	252	.gc = xfrm6_garbage_collect,
	253	.update_pmtu = xfrm6_update_pmtu,
aabc9761 HX	254	.destroy = xfrm6_dst_destroy,
aabc9761 HX	255	.ifdown = xfrm6_dst_ifdown,
862b82c6	256	.local_out = __ip6_local_out,
1da177e4 LT	257	.gc_thresh = 1024,
	258	.entry_size = sizeof(struct xfrm_dst),
	259	};
	260
	261	static struct xfrm_policy_afinfo xfrm6_policy_afinfo = {
	262	.family = AF_INET6,
1da177e4 LT	263	.dst_ops = &xfrm6_dst_ops,
1da177e4 LT	264	.dst_lookup = xfrm6_dst_lookup,
a1e59abf	265	.get_saddr = xfrm6_get_saddr,
1da177e4	266	.find_bundle = __xfrm6_find_bundle,
1da177e4	267	.decode_session = _decode_session6,
25ee3286 HX	268	.get_tos = xfrm6_get_tos,
25ee3286 HX	269	.fill_dst = xfrm6_fill_dst,
1da177e4 LT	270	};
	271
	272	static void __init xfrm6_policy_init(void)
	273	{
	274	xfrm_policy_register_afinfo(&xfrm6_policy_afinfo);
	275	}
	276
	277	static void xfrm6_policy_fini(void)
	278	{
	279	xfrm_policy_unregister_afinfo(&xfrm6_policy_afinfo);
	280	}
	281
	282	void __init xfrm6_init(void)
	283	{
	284	xfrm6_policy_init();
	285	xfrm6_state_init();
	286	}
	287
	288	void xfrm6_fini(void)
	289	{
	290	//xfrm6_input_fini();
	291	xfrm6_policy_fini();
	292	xfrm6_state_fini();
	293	}