mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 19:29:37 +00:00
![Pablo Neira Ayuso](/assets/img/avatar_default.png)
This patch allows us to refer to stateful object dictionaries, the source register indicates the key data to be used to look up for the corresponding state object. We can refer to these maps through names or, alternatively, the map transaction id. This allows us to refer to both anonymous and named maps. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
226 lines
5.7 KiB
C
226 lines
5.7 KiB
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, ®s->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 = nf_tables_set_lookup(ctx->table, tb[NFTA_OBJREF_SET_NAME], genmask);
|
|
if (IS_ERR(set)) {
|
|
if (tb[NFTA_OBJREF_SET_ID]) {
|
|
set = nf_tables_set_lookup_byid(ctx->net,
|
|
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 },
|
|
[NFTA_OBJREF_IMM_TYPE] = { .type = NLA_U32 },
|
|
[NFTA_OBJREF_SET_SREG] = { .type = NLA_U32 },
|
|
[NFTA_OBJREF_SET_NAME] = { .type = NLA_STRING },
|
|
[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");
|