netfilter: nf_tables: add new nft_masq expression

The nft_masq expression is intended to perform NAT in the masquerade flavour.

We decided to have the masquerade functionality in a separated expression other
than nft_nat.

Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Arturo Borrero 2014-09-08 13:45:00 +02:00 committed by Pablo Neira Ayuso
parent be6b635cd6
commit 9ba1f726be
11 changed files with 288 additions and 0 deletions

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@ -0,0 +1,16 @@
#ifndef _NFT_MASQ_H_
#define _NFT_MASQ_H_
struct nft_masq {
u32 flags;
};
extern const struct nla_policy nft_masq_policy[];
int nft_masq_init(const struct nft_ctx *ctx,
const struct nft_expr *expr,
const struct nlattr * const tb[]);
int nft_masq_dump(struct sk_buff *skb, const struct nft_expr *expr);
#endif /* _NFT_MASQ_H_ */

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@ -800,4 +800,15 @@ enum nft_nat_attributes {
};
#define NFTA_NAT_MAX (__NFTA_NAT_MAX - 1)
/**
* enum nft_masq_attributes - nf_tables masquerade expression attributes
*
* @NFTA_MASQ_FLAGS: NAT flags (see NF_NAT_RANGE_* in linux/netfilter/nf_nat.h) (NLA_U32)
*/
enum nft_masq_attributes {
NFTA_MASQ_FLAGS,
__NFTA_MASQ_MAX
};
#define NFTA_MASQ_MAX (__NFTA_MASQ_MAX - 1)
#endif /* _LINUX_NF_TABLES_H */

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@ -190,6 +190,12 @@ config NF_NAT_MASQUERADE_IPV4
This is the kernel functionality to provide NAT in the masquerade
flavour (automatic source address selection).
config NFT_MASQ_IPV4
tristate "IPv4 masquerading support for nf_tables"
depends on NF_TABLES_IPV4
depends on NFT_MASQ
select NF_NAT_MASQUERADE_IPV4
config IP_NF_TARGET_MASQUERADE
tristate "MASQUERADE target support"
select NF_NAT_MASQUERADE_IPV4

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@ -36,6 +36,7 @@ obj-$(CONFIG_NF_TABLES_IPV4) += nf_tables_ipv4.o
obj-$(CONFIG_NFT_CHAIN_ROUTE_IPV4) += nft_chain_route_ipv4.o
obj-$(CONFIG_NFT_CHAIN_NAT_IPV4) += nft_chain_nat_ipv4.o
obj-$(CONFIG_NFT_REJECT_IPV4) += nft_reject_ipv4.o
obj-$(CONFIG_NFT_MASQ_IPV4) += nft_masq_ipv4.o
obj-$(CONFIG_NF_TABLES_ARP) += nf_tables_arp.o
# generic IP tables

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@ -0,0 +1,89 @@
/*
* Copyright (c) 2014 Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables.h>
#include <net/netfilter/nft_masq.h>
#include <net/netfilter/ipv4/nf_nat_masquerade.h>
static void nft_masq_ipv4_eval(const struct nft_expr *expr,
struct nft_data data[NFT_REG_MAX + 1],
const struct nft_pktinfo *pkt)
{
struct nft_masq *priv = nft_expr_priv(expr);
struct nf_nat_range range;
unsigned int verdict;
range.flags = priv->flags;
verdict = nf_nat_masquerade_ipv4(pkt->skb, pkt->ops->hooknum,
&range, pkt->out);
data[NFT_REG_VERDICT].verdict = verdict;
}
static int nft_masq_ipv4_init(const struct nft_ctx *ctx,
const struct nft_expr *expr,
const struct nlattr * const tb[])
{
int err;
err = nft_masq_init(ctx, expr, tb);
if (err < 0)
return err;
nf_nat_masquerade_ipv4_register_notifier();
return 0;
}
static void nft_masq_ipv4_destroy(const struct nft_ctx *ctx,
const struct nft_expr *expr)
{
nf_nat_masquerade_ipv4_unregister_notifier();
}
static struct nft_expr_type nft_masq_ipv4_type;
static const struct nft_expr_ops nft_masq_ipv4_ops = {
.type = &nft_masq_ipv4_type,
.size = NFT_EXPR_SIZE(sizeof(struct nft_masq)),
.eval = nft_masq_ipv4_eval,
.init = nft_masq_ipv4_init,
.destroy = nft_masq_ipv4_destroy,
.dump = nft_masq_dump,
};
static struct nft_expr_type nft_masq_ipv4_type __read_mostly = {
.family = NFPROTO_IPV4,
.name = "masq",
.ops = &nft_masq_ipv4_ops,
.policy = nft_masq_policy,
.maxattr = NFTA_MASQ_MAX,
.owner = THIS_MODULE,
};
static int __init nft_masq_ipv4_module_init(void)
{
return nft_register_expr(&nft_masq_ipv4_type);
}
static void __exit nft_masq_ipv4_module_exit(void)
{
nft_unregister_expr(&nft_masq_ipv4_type);
}
module_init(nft_masq_ipv4_module_init);
module_exit(nft_masq_ipv4_module_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>");
MODULE_ALIAS_NFT_AF_EXPR(AF_INET, "masq");

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@ -252,6 +252,12 @@ config NF_NAT_MASQUERADE_IPV6
This is the kernel functionality to provide NAT in the masquerade
flavour (automatic source address selection) for IPv6.
config NFT_MASQ_IPV6
tristate "IPv6 masquerade support for nf_tables"
depends on NF_TABLES_IPV6
depends on NFT_MASQ
select NF_NAT_MASQUERADE_IPV6
config IP6_NF_TARGET_MASQUERADE
tristate "MASQUERADE target support"
select NF_NAT_MASQUERADE_IPV6

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@ -32,6 +32,7 @@ obj-$(CONFIG_NF_TABLES_IPV6) += nf_tables_ipv6.o
obj-$(CONFIG_NFT_CHAIN_ROUTE_IPV6) += nft_chain_route_ipv6.o
obj-$(CONFIG_NFT_CHAIN_NAT_IPV6) += nft_chain_nat_ipv6.o
obj-$(CONFIG_NFT_REJECT_IPV6) += nft_reject_ipv6.o
obj-$(CONFIG_NFT_MASQ_IPV6) += nft_masq_ipv6.o
# matches
obj-$(CONFIG_IP6_NF_MATCH_AH) += ip6t_ah.o

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@ -0,0 +1,89 @@
/*
* Copyright (c) 2014 Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables.h>
#include <net/netfilter/nf_nat.h>
#include <net/netfilter/nft_masq.h>
#include <net/netfilter/ipv6/nf_nat_masquerade.h>
static void nft_masq_ipv6_eval(const struct nft_expr *expr,
struct nft_data data[NFT_REG_MAX + 1],
const struct nft_pktinfo *pkt)
{
struct nft_masq *priv = nft_expr_priv(expr);
struct nf_nat_range range;
unsigned int verdict;
range.flags = priv->flags;
verdict = nf_nat_masquerade_ipv6(pkt->skb, &range, pkt->out);
data[NFT_REG_VERDICT].verdict = verdict;
}
static int nft_masq_ipv6_init(const struct nft_ctx *ctx,
const struct nft_expr *expr,
const struct nlattr * const tb[])
{
int err;
err = nft_masq_init(ctx, expr, tb);
if (err < 0)
return err;
nf_nat_masquerade_ipv6_register_notifier();
return 0;
}
static void nft_masq_ipv6_destroy(const struct nft_ctx *ctx,
const struct nft_expr *expr)
{
nf_nat_masquerade_ipv6_unregister_notifier();
}
static struct nft_expr_type nft_masq_ipv6_type;
static const struct nft_expr_ops nft_masq_ipv6_ops = {
.type = &nft_masq_ipv6_type,
.size = NFT_EXPR_SIZE(sizeof(struct nft_masq)),
.eval = nft_masq_ipv6_eval,
.init = nft_masq_ipv6_init,
.destroy = nft_masq_ipv6_destroy,
.dump = nft_masq_dump,
};
static struct nft_expr_type nft_masq_ipv6_type __read_mostly = {
.family = NFPROTO_IPV6,
.name = "masq",
.ops = &nft_masq_ipv6_ops,
.policy = nft_masq_policy,
.maxattr = NFTA_MASQ_MAX,
.owner = THIS_MODULE,
};
static int __init nft_masq_ipv6_module_init(void)
{
return nft_register_expr(&nft_masq_ipv6_type);
}
static void __exit nft_masq_ipv6_module_exit(void)
{
nft_unregister_expr(&nft_masq_ipv6_type);
}
module_init(nft_masq_ipv6_module_init);
module_exit(nft_masq_ipv6_module_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>");
MODULE_ALIAS_NFT_AF_EXPR(AF_INET6, "masq");

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@ -496,6 +496,15 @@ config NFT_LIMIT
This option adds the "limit" expression that you can use to
ratelimit rule matchings.
config NFT_MASQ
depends on NF_TABLES
depends on NF_CONNTRACK
depends on NF_NAT
tristate "Netfilter nf_tables masquerade support"
help
This option adds the "masquerade" expression that you can use
to perform NAT in the masquerade flavour.
config NFT_NAT
depends on NF_TABLES
depends on NF_CONNTRACK

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@ -87,6 +87,7 @@ obj-$(CONFIG_NFT_RBTREE) += nft_rbtree.o
obj-$(CONFIG_NFT_HASH) += nft_hash.o
obj-$(CONFIG_NFT_COUNTER) += nft_counter.o
obj-$(CONFIG_NFT_LOG) += nft_log.o
obj-$(CONFIG_NFT_MASQ) += nft_masq.o
# generic X tables
obj-$(CONFIG_NETFILTER_XTABLES) += x_tables.o xt_tcpudp.o

59
net/netfilter/nft_masq.c Normal file
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@ -0,0 +1,59 @@
/*
* Copyright (c) 2014 Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables.h>
#include <net/netfilter/nf_nat.h>
#include <net/netfilter/nft_masq.h>
const struct nla_policy nft_masq_policy[NFTA_MASQ_MAX + 1] = {
[NFTA_MASQ_FLAGS] = { .type = NLA_U32 },
};
EXPORT_SYMBOL_GPL(nft_masq_policy);
int nft_masq_init(const struct nft_ctx *ctx,
const struct nft_expr *expr,
const struct nlattr * const tb[])
{
struct nft_masq *priv = nft_expr_priv(expr);
if (tb[NFTA_MASQ_FLAGS] == NULL)
return 0;
priv->flags = ntohl(nla_get_be32(tb[NFTA_MASQ_FLAGS]));
if (priv->flags & ~NF_NAT_RANGE_MASK)
return -EINVAL;
return 0;
}
EXPORT_SYMBOL_GPL(nft_masq_init);
int nft_masq_dump(struct sk_buff *skb, const struct nft_expr *expr)
{
const struct nft_masq *priv = nft_expr_priv(expr);
if (priv->flags == 0)
return 0;
if (nla_put_be32(skb, NFTA_MASQ_FLAGS, htonl(priv->flags)))
goto nla_put_failure;
return 0;
nla_put_failure:
return -1;
}
EXPORT_SYMBOL_GPL(nft_masq_dump);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>");