[mirror_ubuntu-artful-kernel.git] / net / netfilter / nft_objref.c

/*
 * Copyright (c) 2012-2016 Pablo Neira Ayuso <pablo@netfilter.org>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables.h>

#define nft_objref_priv(expr)	*((struct nft_object **)nft_expr_priv(expr))

static void nft_objref_eval(const struct nft_expr *expr,
			    struct nft_regs *regs,
			    const struct nft_pktinfo *pkt)
{
	struct nft_object *obj = nft_objref_priv(expr);

	obj->type->eval(obj, regs, pkt);
}

static int nft_objref_init(const struct nft_ctx *ctx,
			   const struct nft_expr *expr,
			   const struct nlattr * const tb[])
{
	struct nft_object *obj = nft_objref_priv(expr);
	u8 genmask = nft_genmask_next(ctx->net);
	u32 objtype;

	if (!tb[NFTA_OBJREF_IMM_NAME] ||
	    !tb[NFTA_OBJREF_IMM_TYPE])
		return -EINVAL;

	objtype = ntohl(nla_get_be32(tb[NFTA_OBJREF_IMM_TYPE]));
	obj = nf_tables_obj_lookup(ctx->table, tb[NFTA_OBJREF_IMM_NAME], objtype,
				   genmask);
	if (IS_ERR(obj))
		return -ENOENT;

	nft_objref_priv(expr) = obj;
	obj->use++;

	return 0;
}

static int nft_objref_dump(struct sk_buff *skb, const struct nft_expr *expr)
{
	const struct nft_object *obj = nft_objref_priv(expr);

	if (nla_put_string(skb, NFTA_OBJREF_IMM_NAME, obj->name) ||
	    nla_put_be32(skb, NFTA_OBJREF_IMM_TYPE, htonl(obj->type->type)))
		goto nla_put_failure;

	return 0;

nla_put_failure:
	return -1;
}

static void nft_objref_destroy(const struct nft_ctx *ctx,
			       const struct nft_expr *expr)
{
	struct nft_object *obj = nft_objref_priv(expr);

	obj->use--;
}

static struct nft_expr_type nft_objref_type;
static const struct nft_expr_ops nft_objref_ops = {
	.type		= &nft_objref_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_object *)),
	.eval		= nft_objref_eval,
	.init		= nft_objref_init,
	.destroy	= nft_objref_destroy,
	.dump		= nft_objref_dump,
};

struct nft_objref_map {
	struct nft_set		*set;
	enum nft_registers	sreg:8;
	struct nft_set_binding	binding;
};

static void nft_objref_map_eval(const struct nft_expr *expr,
				struct nft_regs *regs,
				const struct nft_pktinfo *pkt)
{
	struct nft_objref_map *priv = nft_expr_priv(expr);
	const struct nft_set *set = priv->set;
	const struct nft_set_ext *ext;
	struct nft_object *obj;
	bool found;

	found = set->ops->lookup(nft_net(pkt), set, &regs->data[priv->sreg],
				 &ext);
	if (!found) {
		regs->verdict.code = NFT_BREAK;
		return;
	}
	obj = *nft_set_ext_obj(ext);
	obj->type->eval(obj, regs, pkt);
}

static int nft_objref_map_init(const struct nft_ctx *ctx,
			       const struct nft_expr *expr,
			       const struct nlattr * const tb[])
{
	struct nft_objref_map *priv = nft_expr_priv(expr);
	u8 genmask = nft_genmask_next(ctx->net);
	struct nft_set *set;
	int err;

	set = nft_set_lookup(ctx->net, ctx->table, tb[NFTA_OBJREF_SET_NAME],
			     tb[NFTA_OBJREF_SET_ID], genmask);
	if (IS_ERR(set))
		return PTR_ERR(set);

	if (!(set->flags & NFT_SET_OBJECT))
		return -EINVAL;

	priv->sreg = nft_parse_register(tb[NFTA_OBJREF_SET_SREG]);
	err = nft_validate_register_load(priv->sreg, set->klen);
	if (err < 0)
		return err;

	priv->binding.flags = set->flags & NFT_SET_OBJECT;

	err = nf_tables_bind_set(ctx, set, &priv->binding);
	if (err < 0)
		return err;

	priv->set = set;
	return 0;
}

static int nft_objref_map_dump(struct sk_buff *skb, const struct nft_expr *expr)
{
	const struct nft_objref_map *priv = nft_expr_priv(expr);

	if (nft_dump_register(skb, NFTA_OBJREF_SET_SREG, priv->sreg) ||
	    nla_put_string(skb, NFTA_OBJREF_SET_NAME, priv->set->name))
		goto nla_put_failure;

	return 0;

nla_put_failure:
	return -1;
}

static void nft_objref_map_destroy(const struct nft_ctx *ctx,
				   const struct nft_expr *expr)
{
	struct nft_objref_map *priv = nft_expr_priv(expr);

	nf_tables_unbind_set(ctx, priv->set, &priv->binding);
}

static struct nft_expr_type nft_objref_type;
static const struct nft_expr_ops nft_objref_map_ops = {
	.type		= &nft_objref_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_objref_map)),
	.eval		= nft_objref_map_eval,
	.init		= nft_objref_map_init,
	.destroy	= nft_objref_map_destroy,
	.dump		= nft_objref_map_dump,
};

static const struct nft_expr_ops *
nft_objref_select_ops(const struct nft_ctx *ctx,
                      const struct nlattr * const tb[])
{
	if (tb[NFTA_OBJREF_SET_SREG] &&
	    (tb[NFTA_OBJREF_SET_NAME] ||
	     tb[NFTA_OBJREF_SET_ID]))
		return &nft_objref_map_ops;
	else if (tb[NFTA_OBJREF_IMM_NAME] &&
		 tb[NFTA_OBJREF_IMM_TYPE])
		return &nft_objref_ops;

	return ERR_PTR(-EOPNOTSUPP);
}

static const struct nla_policy nft_objref_policy[NFTA_OBJREF_MAX + 1] = {
	[NFTA_OBJREF_IMM_NAME]	= { .type = NLA_STRING,
				    .len = NFT_OBJ_MAXNAMELEN - 1 },
	[NFTA_OBJREF_IMM_TYPE]	= { .type = NLA_U32 },
	[NFTA_OBJREF_SET_SREG]	= { .type = NLA_U32 },
	[NFTA_OBJREF_SET_NAME]	= { .type = NLA_STRING,
				    .len = NFT_SET_MAXNAMELEN - 1 },
	[NFTA_OBJREF_SET_ID]	= { .type = NLA_U32 },
};

static struct nft_expr_type nft_objref_type __read_mostly = {
	.name		= "objref",
	.select_ops	= nft_objref_select_ops,
	.policy		= nft_objref_policy,
	.maxattr	= NFTA_OBJREF_MAX,
	.owner		= THIS_MODULE,
};

static int __init nft_objref_module_init(void)
{
	return nft_register_expr(&nft_objref_type);
}

static void __exit nft_objref_module_exit(void)
{
	nft_unregister_expr(&nft_objref_type);
}

module_init(nft_objref_module_init);
module_exit(nft_objref_module_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
MODULE_ALIAS_NFT_EXPR("objref");
Commit	Line	Data
c97d22e6 PNA	1	/*
	2	* Copyright (c) 2012-2016 Pablo Neira Ayuso <pablo@netfilter.org>
	3	*
	4	* This program is free software; you can redistribute it and/or modify it
	5	* under the terms and conditions of the GNU General Public License,
	6	* version 2, as published by the Free Software Foundation.
	7	*/
	8
	9	#include <linux/init.h>
	10	#include <linux/module.h>
	11	#include <linux/skbuff.h>
	12	#include <linux/netlink.h>
	13	#include <linux/netfilter.h>
	14	#include <linux/netfilter/nf_tables.h>
	15	#include <net/netfilter/nf_tables.h>
	16
	17	#define nft_objref_priv(expr) ((struct nft_object *)nft_expr_priv(expr))
	18
	19	static void nft_objref_eval(const struct nft_expr *expr,
	20	struct nft_regs *regs,
	21	const struct nft_pktinfo *pkt)
	22	{
	23	struct nft_object *obj = nft_objref_priv(expr);
	24
	25	obj->type->eval(obj, regs, pkt);
	26	}
	27
	28	static int nft_objref_init(const struct nft_ctx *ctx,
	29	const struct nft_expr *expr,
	30	const struct nlattr * const tb[])
	31	{
	32	struct nft_object *obj = nft_objref_priv(expr);
	33	u8 genmask = nft_genmask_next(ctx->net);
	34	u32 objtype;
	35
	36	if (!tb[NFTA_OBJREF_IMM_NAME] \|\|
	37	!tb[NFTA_OBJREF_IMM_TYPE])
	38	return -EINVAL;
	39
	40	objtype = ntohl(nla_get_be32(tb[NFTA_OBJREF_IMM_TYPE]));
	41	obj = nf_tables_obj_lookup(ctx->table, tb[NFTA_OBJREF_IMM_NAME], objtype,
	42	genmask);
	43	if (IS_ERR(obj))
	44	return -ENOENT;
	45
	46	nft_objref_priv(expr) = obj;
	47	obj->use++;
	48
	49	return 0;
	50	}
	51
	52	static int nft_objref_dump(struct sk_buff skb, const struct nft_expr expr)
	53	{
	54	const struct nft_object *obj = nft_objref_priv(expr);
	55
	56	if (nla_put_string(skb, NFTA_OBJREF_IMM_NAME, obj->name) \|\|
	57	nla_put_be32(skb, NFTA_OBJREF_IMM_TYPE, htonl(obj->type->type)))
	58	goto nla_put_failure;
	59
	60	return 0;
	61
	62	nla_put_failure:
	63	return -1;
	64	}
65
66	static void nft_objref_destroy(const struct nft_ctx *ctx,
67	const struct nft_expr *expr)
68	{
69	struct nft_object *obj = nft_objref_priv(expr);
70
71	obj->use--;
72	}
73
74	static struct nft_expr_type nft_objref_type;
75	static const struct nft_expr_ops nft_objref_ops = {
76	.type = &nft_objref_type,
77	.size = NFT_EXPR_SIZE(sizeof(struct nft_object *)),
78	.eval = nft_objref_eval,
79	.init = nft_objref_init,
80	.destroy = nft_objref_destroy,
81	.dump = nft_objref_dump,
82	};
83
63aea290 PNA	84	struct nft_objref_map {
	85	struct nft_set *set;
	86	enum nft_registers sreg:8;
	87	struct nft_set_binding binding;
	88	};
	89
	90	static void nft_objref_map_eval(const struct nft_expr *expr,
	91	struct nft_regs *regs,
	92	const struct nft_pktinfo *pkt)
	93	{
	94	struct nft_objref_map *priv = nft_expr_priv(expr);
	95	const struct nft_set *set = priv->set;
	96	const struct nft_set_ext *ext;
	97	struct nft_object *obj;
	98	bool found;
	99
	100	found = set->ops->lookup(nft_net(pkt), set, &regs->data[priv->sreg],
	101	&ext);
	102	if (!found) {
	103	regs->verdict.code = NFT_BREAK;
	104	return;
	105	}
	106	obj = *nft_set_ext_obj(ext);
	107	obj->type->eval(obj, regs, pkt);
	108	}
	109
	110	static int nft_objref_map_init(const struct nft_ctx *ctx,
	111	const struct nft_expr *expr,
	112	const struct nlattr * const tb[])
	113	{
	114	struct nft_objref_map *priv = nft_expr_priv(expr);
	115	u8 genmask = nft_genmask_next(ctx->net);
	116	struct nft_set *set;
	117	int err;
	118
c7a72e3f PNA	119	set = nft_set_lookup(ctx->net, ctx->table, tb[NFTA_OBJREF_SET_NAME],
	120	tb[NFTA_OBJREF_SET_ID], genmask);
	121	if (IS_ERR(set))
	122	return PTR_ERR(set);
63aea290 PNA	123
	124	if (!(set->flags & NFT_SET_OBJECT))
	125	return -EINVAL;
	126
	127	priv->sreg = nft_parse_register(tb[NFTA_OBJREF_SET_SREG]);
	128	err = nft_validate_register_load(priv->sreg, set->klen);
	129	if (err < 0)
	130	return err;
	131
	132	priv->binding.flags = set->flags & NFT_SET_OBJECT;
	133
	134	err = nf_tables_bind_set(ctx, set, &priv->binding);
	135	if (err < 0)
	136	return err;
	137
	138	priv->set = set;
	139	return 0;
	140	}
	141
	142	static int nft_objref_map_dump(struct sk_buff skb, const struct nft_expr expr)
	143	{
	144	const struct nft_objref_map *priv = nft_expr_priv(expr);
	145
	146	if (nft_dump_register(skb, NFTA_OBJREF_SET_SREG, priv->sreg) \|\|
	147	nla_put_string(skb, NFTA_OBJREF_SET_NAME, priv->set->name))
	148	goto nla_put_failure;
	149
	150	return 0;
	151
	152	nla_put_failure:
	153	return -1;
	154	}
	155
	156	static void nft_objref_map_destroy(const struct nft_ctx *ctx,
	157	const struct nft_expr *expr)
	158	{
	159	struct nft_objref_map *priv = nft_expr_priv(expr);
	160
	161	nf_tables_unbind_set(ctx, priv->set, &priv->binding);
	162	}
	163
	164	static struct nft_expr_type nft_objref_type;
	165	static const struct nft_expr_ops nft_objref_map_ops = {
	166	.type = &nft_objref_type,
	167	.size = NFT_EXPR_SIZE(sizeof(struct nft_objref_map)),
	168	.eval = nft_objref_map_eval,
	169	.init = nft_objref_map_init,
	170	.destroy = nft_objref_map_destroy,
	171	.dump = nft_objref_map_dump,
	172	};
	173
	174	static const struct nft_expr_ops *
	175	nft_objref_select_ops(const struct nft_ctx *ctx,
	176	const struct nlattr * const tb[])
	177	{
	178	if (tb[NFTA_OBJREF_SET_SREG] &&
	179	(tb[NFTA_OBJREF_SET_NAME] \|\|
	180	tb[NFTA_OBJREF_SET_ID]))
	181	return &nft_objref_map_ops;
	182	else if (tb[NFTA_OBJREF_IMM_NAME] &&
	183	tb[NFTA_OBJREF_IMM_TYPE])
	184	return &nft_objref_ops;
	185
	186	return ERR_PTR(-EOPNOTSUPP);
187	}
188
c97d22e6	189	static const struct nla_policy nft_objref_policy[NFTA_OBJREF_MAX + 1] = {
b2fbd044 LZ	190	[NFTA_OBJREF_IMM_NAME] = { .type = NLA_STRING,
b2fbd044 LZ	191	.len = NFT_OBJ_MAXNAMELEN - 1 },
c97d22e6	192	[NFTA_OBJREF_IMM_TYPE] = { .type = NLA_U32 },
63aea290	193	[NFTA_OBJREF_SET_SREG] = { .type = NLA_U32 },
b2fbd044 LZ	194	[NFTA_OBJREF_SET_NAME] = { .type = NLA_STRING,
b2fbd044 LZ	195	.len = NFT_SET_MAXNAMELEN - 1 },
63aea290	196	[NFTA_OBJREF_SET_ID] = { .type = NLA_U32 },
c97d22e6 PNA	197	};
	198
	199	static struct nft_expr_type nft_objref_type __read_mostly = {
	200	.name = "objref",
63aea290	201	.select_ops = nft_objref_select_ops,
c97d22e6 PNA	202	.policy = nft_objref_policy,
	203	.maxattr = NFTA_OBJREF_MAX,
	204	.owner = THIS_MODULE,
	205	};
	206
	207	static int __init nft_objref_module_init(void)
	208	{
	209	return nft_register_expr(&nft_objref_type);
	210	}
	211
	212	static void __exit nft_objref_module_exit(void)
	213	{
	214	nft_unregister_expr(&nft_objref_type);
	215	}
	216
	217	module_init(nft_objref_module_init);
	218	module_exit(nft_objref_module_exit);
	219
	220	MODULE_LICENSE("GPL");
	221	MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
	222	MODULE_ALIAS_NFT_EXPR("objref");