[deliverable/linux.git] / net / core / lwtunnel.c

/*
 * lwtunnel	Infrastructure for light weight tunnels like mpls
 *
 * Authors:	Roopa Prabhu, <roopa@cumulusnetworks.com>
 *
 *		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.
 *
 */

#include <linux/capability.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/lwtunnel.h>
#include <linux/in.h>
#include <linux/init.h>
#include <linux/err.h>

#include <net/lwtunnel.h>
#include <net/rtnetlink.h>
#include <net/ip6_fib.h>

struct lwtunnel_state *lwtunnel_state_alloc(int encap_len)
{
	struct lwtunnel_state *lws;

	lws = kzalloc(sizeof(*lws) + encap_len, GFP_ATOMIC);

	return lws;
}
EXPORT_SYMBOL(lwtunnel_state_alloc);

static const struct lwtunnel_encap_ops __rcu *
		lwtun_encaps[LWTUNNEL_ENCAP_MAX + 1] __read_mostly;

int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *ops,
			   unsigned int num)
{
	if (num > LWTUNNEL_ENCAP_MAX)
		return -ERANGE;

	return !cmpxchg((const struct lwtunnel_encap_ops **)
			&lwtun_encaps[num],
			NULL, ops) ? 0 : -1;
}
EXPORT_SYMBOL(lwtunnel_encap_add_ops);

int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *ops,
			   unsigned int encap_type)
{
	int ret;

	if (encap_type == LWTUNNEL_ENCAP_NONE ||
	    encap_type > LWTUNNEL_ENCAP_MAX)
		return -ERANGE;

	ret = (cmpxchg((const struct lwtunnel_encap_ops **)
		       &lwtun_encaps[encap_type],
		       ops, NULL) == ops) ? 0 : -1;

	synchronize_net();

	return ret;
}
EXPORT_SYMBOL(lwtunnel_encap_del_ops);

int lwtunnel_build_state(struct net_device *dev, u16 encap_type,
			 struct nlattr *encap, unsigned int family,
			 const void *cfg, struct lwtunnel_state **lws)
{
	const struct lwtunnel_encap_ops *ops;
	int ret = -EINVAL;

	if (encap_type == LWTUNNEL_ENCAP_NONE ||
	    encap_type > LWTUNNEL_ENCAP_MAX)
		return ret;

	ret = -EOPNOTSUPP;
	rcu_read_lock();
	ops = rcu_dereference(lwtun_encaps[encap_type]);
	if (likely(ops && ops->build_state))
		ret = ops->build_state(dev, encap, family, cfg, lws);
	rcu_read_unlock();

	return ret;
}
EXPORT_SYMBOL(lwtunnel_build_state);

int lwtunnel_fill_encap(struct sk_buff *skb, struct lwtunnel_state *lwtstate)
{
	const struct lwtunnel_encap_ops *ops;
	struct nlattr *nest;
	int ret = -EINVAL;

	if (!lwtstate)
		return 0;

	if (lwtstate->type == LWTUNNEL_ENCAP_NONE ||
	    lwtstate->type > LWTUNNEL_ENCAP_MAX)
		return 0;

	ret = -EOPNOTSUPP;
	nest = nla_nest_start(skb, RTA_ENCAP);
	rcu_read_lock();
	ops = rcu_dereference(lwtun_encaps[lwtstate->type]);
	if (likely(ops && ops->fill_encap))
		ret = ops->fill_encap(skb, lwtstate);
	rcu_read_unlock();

	if (ret)
		goto nla_put_failure;
	nla_nest_end(skb, nest);
	ret = nla_put_u16(skb, RTA_ENCAP_TYPE, lwtstate->type);
	if (ret)
		goto nla_put_failure;

	return 0;

nla_put_failure:
	nla_nest_cancel(skb, nest);

	return (ret == -EOPNOTSUPP ? 0 : ret);
}
EXPORT_SYMBOL(lwtunnel_fill_encap);

int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate)
{
	const struct lwtunnel_encap_ops *ops;
	int ret = 0;

	if (!lwtstate)
		return 0;

	if (lwtstate->type == LWTUNNEL_ENCAP_NONE ||
	    lwtstate->type > LWTUNNEL_ENCAP_MAX)
		return 0;

	rcu_read_lock();
	ops = rcu_dereference(lwtun_encaps[lwtstate->type]);
	if (likely(ops && ops->get_encap_size))
		ret = nla_total_size(ops->get_encap_size(lwtstate));
	rcu_read_unlock();

	return ret;
}
EXPORT_SYMBOL(lwtunnel_get_encap_size);

int lwtunnel_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b)
{
	const struct lwtunnel_encap_ops *ops;
	int ret = 0;

	if (!a && !b)
		return 0;

	if (!a || !b)
		return 1;

	if (a->type != b->type)
		return 1;

	if (a->type == LWTUNNEL_ENCAP_NONE ||
	    a->type > LWTUNNEL_ENCAP_MAX)
		return 0;

	rcu_read_lock();
	ops = rcu_dereference(lwtun_encaps[a->type]);
	if (likely(ops && ops->cmp_encap))
		ret = ops->cmp_encap(a, b);
	rcu_read_unlock();

	return ret;
}
EXPORT_SYMBOL(lwtunnel_cmp_encap);

int lwtunnel_output(struct sock *sk, struct sk_buff *skb)
{
	struct dst_entry *dst = skb_dst(skb);
	const struct lwtunnel_encap_ops *ops;
	struct lwtunnel_state *lwtstate;
	int ret = -EINVAL;

	if (!dst)
		goto drop;
	lwtstate = dst->lwtstate;

	if (lwtstate->type == LWTUNNEL_ENCAP_NONE ||
	    lwtstate->type > LWTUNNEL_ENCAP_MAX)
		return 0;

	ret = -EOPNOTSUPP;
	rcu_read_lock();
	ops = rcu_dereference(lwtun_encaps[lwtstate->type]);
	if (likely(ops && ops->output))
		ret = ops->output(sk, skb);
	rcu_read_unlock();

	if (ret == -EOPNOTSUPP)
		goto drop;

	return ret;

drop:
	kfree_skb(skb);

	return ret;
}
EXPORT_SYMBOL(lwtunnel_output);

int lwtunnel_input(struct sk_buff *skb)
{
	struct dst_entry *dst = skb_dst(skb);
	const struct lwtunnel_encap_ops *ops;
	struct lwtunnel_state *lwtstate;
	int ret = -EINVAL;

	if (!dst)
		goto drop;
	lwtstate = dst->lwtstate;

	if (lwtstate->type == LWTUNNEL_ENCAP_NONE ||
	    lwtstate->type > LWTUNNEL_ENCAP_MAX)
		return 0;

	ret = -EOPNOTSUPP;
	rcu_read_lock();
	ops = rcu_dereference(lwtun_encaps[lwtstate->type]);
	if (likely(ops && ops->input))
		ret = ops->input(skb);
	rcu_read_unlock();

	if (ret == -EOPNOTSUPP)
		goto drop;

	return ret;

drop:
	kfree_skb(skb);

	return ret;
}
EXPORT_SYMBOL(lwtunnel_input);
Commit	Line	Data
499a2425 RP	1	/*
	2	* lwtunnel Infrastructure for light weight tunnels like mpls
	3	*
	4	* Authors: Roopa Prabhu, <roopa@cumulusnetworks.com>
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License
	8	* as published by the Free Software Foundation; either version
	9	* 2 of the License, or (at your option) any later version.
	10	*
	11	*/
	12
	13	#include <linux/capability.h>
	14	#include <linux/module.h>
	15	#include <linux/types.h>
	16	#include <linux/kernel.h>
	17	#include <linux/slab.h>
	18	#include <linux/uaccess.h>
	19	#include <linux/skbuff.h>
	20	#include <linux/netdevice.h>
	21	#include <linux/lwtunnel.h>
	22	#include <linux/in.h>
	23	#include <linux/init.h>
	24	#include <linux/err.h>
	25
	26	#include <net/lwtunnel.h>
	27	#include <net/rtnetlink.h>
ffce4196	28	#include <net/ip6_fib.h>
499a2425 RP	29
	30	struct lwtunnel_state *lwtunnel_state_alloc(int encap_len)
	31	{
	32	struct lwtunnel_state *lws;
	33
	34	lws = kzalloc(sizeof(*lws) + encap_len, GFP_ATOMIC);
	35
	36	return lws;
	37	}
	38	EXPORT_SYMBOL(lwtunnel_state_alloc);
	39
92a99bf3	40	static const struct lwtunnel_encap_ops __rcu *
499a2425 RP	41	lwtun_encaps[LWTUNNEL_ENCAP_MAX + 1] __read_mostly;
	42
	43	int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *ops,
	44	unsigned int num)
	45	{
	46	if (num > LWTUNNEL_ENCAP_MAX)
	47	return -ERANGE;
	48
	49	return !cmpxchg((const struct lwtunnel_encap_ops **)
	50	&lwtun_encaps[num],
	51	NULL, ops) ? 0 : -1;
	52	}
	53	EXPORT_SYMBOL(lwtunnel_encap_add_ops);
	54
	55	int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *ops,
	56	unsigned int encap_type)
	57	{
	58	int ret;
	59
	60	if (encap_type == LWTUNNEL_ENCAP_NONE \|\|
	61	encap_type > LWTUNNEL_ENCAP_MAX)
	62	return -ERANGE;
	63
	64	ret = (cmpxchg((const struct lwtunnel_encap_ops **)
	65	&lwtun_encaps[encap_type],
	66	ops, NULL) == ops) ? 0 : -1;
	67
	68	synchronize_net();
	69
	70	return ret;
	71	}
	72	EXPORT_SYMBOL(lwtunnel_encap_del_ops);
	73
	74	int lwtunnel_build_state(struct net_device *dev, u16 encap_type,
127eb7cd TH	75	struct nlattr *encap, unsigned int family,
127eb7cd TH	76	const void cfg, struct lwtunnel_state *lws)
499a2425 RP	77	{
	78	const struct lwtunnel_encap_ops *ops;
	79	int ret = -EINVAL;
	80
	81	if (encap_type == LWTUNNEL_ENCAP_NONE \|\|
	82	encap_type > LWTUNNEL_ENCAP_MAX)
	83	return ret;
	84
	85	ret = -EOPNOTSUPP;
	86	rcu_read_lock();
	87	ops = rcu_dereference(lwtun_encaps[encap_type]);
	88	if (likely(ops && ops->build_state))
127eb7cd	89	ret = ops->build_state(dev, encap, family, cfg, lws);
499a2425 RP	90	rcu_read_unlock();
	91
	92	return ret;
	93	}
	94	EXPORT_SYMBOL(lwtunnel_build_state);
	95
	96	int lwtunnel_fill_encap(struct sk_buff skb, struct lwtunnel_state lwtstate)
	97	{
	98	const struct lwtunnel_encap_ops *ops;
	99	struct nlattr *nest;
	100	int ret = -EINVAL;
	101
	102	if (!lwtstate)
	103	return 0;
	104
	105	if (lwtstate->type == LWTUNNEL_ENCAP_NONE \|\|
	106	lwtstate->type > LWTUNNEL_ENCAP_MAX)
	107	return 0;
	108
	109	ret = -EOPNOTSUPP;
	110	nest = nla_nest_start(skb, RTA_ENCAP);
	111	rcu_read_lock();
	112	ops = rcu_dereference(lwtun_encaps[lwtstate->type]);
	113	if (likely(ops && ops->fill_encap))
	114	ret = ops->fill_encap(skb, lwtstate);
	115	rcu_read_unlock();
	116
	117	if (ret)
	118	goto nla_put_failure;
	119	nla_nest_end(skb, nest);
	120	ret = nla_put_u16(skb, RTA_ENCAP_TYPE, lwtstate->type);
	121	if (ret)
	122	goto nla_put_failure;
	123
	124	return 0;
	125
	126	nla_put_failure:
	127	nla_nest_cancel(skb, nest);
	128
	129	return (ret == -EOPNOTSUPP ? 0 : ret);
	130	}
	131	EXPORT_SYMBOL(lwtunnel_fill_encap);
	132
	133	int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate)
	134	{
	135	const struct lwtunnel_encap_ops *ops;
	136	int ret = 0;
	137
	138	if (!lwtstate)
	139	return 0;
	140
	141	if (lwtstate->type == LWTUNNEL_ENCAP_NONE \|\|
	142	lwtstate->type > LWTUNNEL_ENCAP_MAX)
	143	return 0;
	144
	145	rcu_read_lock();
	146	ops = rcu_dereference(lwtun_encaps[lwtstate->type]);
	147	if (likely(ops && ops->get_encap_size))
	148	ret = nla_total_size(ops->get_encap_size(lwtstate));
	149	rcu_read_unlock();
	150
	151	return ret;
	152	}
	153	EXPORT_SYMBOL(lwtunnel_get_encap_size);
154
155	int lwtunnel_cmp_encap(struct lwtunnel_state a, struct lwtunnel_state b)
156	{
157	const struct lwtunnel_encap_ops *ops;
158	int ret = 0;
159
160	if (!a && !b)
161	return 0;
162
163	if (!a \|\| !b)
164	return 1;
165
166	if (a->type != b->type)
167	return 1;
168
169	if (a->type == LWTUNNEL_ENCAP_NONE \|\|
170	a->type > LWTUNNEL_ENCAP_MAX)
171	return 0;
172
173	rcu_read_lock();
174	ops = rcu_dereference(lwtun_encaps[a->type]);
175	if (likely(ops && ops->cmp_encap))
176	ret = ops->cmp_encap(a, b);
177	rcu_read_unlock();
178
179	return ret;
180	}
181	EXPORT_SYMBOL(lwtunnel_cmp_encap);
ffce4196	182
61adedf3	183	int lwtunnel_output(struct sock sk, struct sk_buff skb)
ffce4196	184	{
61adedf3	185	struct dst_entry *dst = skb_dst(skb);
ffce4196	186	const struct lwtunnel_encap_ops *ops;
61adedf3	187	struct lwtunnel_state *lwtstate;
ffce4196 RP	188	int ret = -EINVAL;
ffce4196 RP	189
61adedf3	190	if (!dst)
ffce4196	191	goto drop;
61adedf3	192	lwtstate = dst->lwtstate;
ffce4196 RP	193
	194	if (lwtstate->type == LWTUNNEL_ENCAP_NONE \|\|
	195	lwtstate->type > LWTUNNEL_ENCAP_MAX)
	196	return 0;
	197
	198	ret = -EOPNOTSUPP;
	199	rcu_read_lock();
	200	ops = rcu_dereference(lwtun_encaps[lwtstate->type]);
	201	if (likely(ops && ops->output))
	202	ret = ops->output(sk, skb);
	203	rcu_read_unlock();
	204
	205	if (ret == -EOPNOTSUPP)
	206	goto drop;
	207
	208	return ret;
	209
	210	drop:
e11f40b9	211	kfree_skb(skb);
ffce4196 RP	212
	213	return ret;
	214	}
ffce4196	215	EXPORT_SYMBOL(lwtunnel_output);
25368623	216
61adedf3	217	int lwtunnel_input(struct sk_buff *skb)
25368623	218	{
61adedf3	219	struct dst_entry *dst = skb_dst(skb);
25368623	220	const struct lwtunnel_encap_ops *ops;
61adedf3	221	struct lwtunnel_state *lwtstate;
25368623 TH	222	int ret = -EINVAL;
25368623 TH	223
61adedf3	224	if (!dst)
25368623	225	goto drop;
61adedf3	226	lwtstate = dst->lwtstate;
25368623 TH	227
	228	if (lwtstate->type == LWTUNNEL_ENCAP_NONE \|\|
	229	lwtstate->type > LWTUNNEL_ENCAP_MAX)
	230	return 0;
	231
	232	ret = -EOPNOTSUPP;
	233	rcu_read_lock();
	234	ops = rcu_dereference(lwtun_encaps[lwtstate->type]);
	235	if (likely(ops && ops->input))
	236	ret = ops->input(skb);
	237	rcu_read_unlock();
	238
	239	if (ret == -EOPNOTSUPP)
	240	goto drop;
	241
	242	return ret;
	243
	244	drop:
	245	kfree_skb(skb);
	246
	247	return ret;
	248	}
25368623	249	EXPORT_SYMBOL(lwtunnel_input);