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netfilter: nf_tables: Add support for IPv6 NAT

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This patch generalizes the NAT expression to support both IPv4 and IPv6
using the existing IPv4/IPv6 NAT infrastructure. This also adds the
NAT chain type for IPv6.

This patch collapses the following patches that were posted to the
netfilter-devel mailing list, from Tomasz:

* nf_tables: Change NFTA_NAT_ attributes to better semantic significance
* nf_tables: Split IPv4 NAT into NAT expression and IPv4 NAT chain
* nf_tables: Add support for IPv6 NAT expression
* nf_tables: Add support for IPv6 NAT chain
* nf_tables: Fix up build issue on IPv6 NAT support

And, from Pablo Neira Ayuso:

* fix missing dependencies in nft_chain_nat

Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Tomasz Bursztyka 2013-10-10 13:39:19 +02:00 committed by Pablo Neira Ayuso
parent 9ddf632357
commit eb31628e37
9 changed files with 457 additions and 162 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
include/uapi/linux/netfilter/nf_tables.h
View File

@ -695,18 +695,20 @@ enum nft_nat_types {
* enum nft_nat_attributes - nf_tables nat expression netlink attributes * enum nft_nat_attributes - nf_tables nat expression netlink attributes
* *
* @NFTA_NAT_TYPE: NAT type (NLA_U32: nft_nat_types) * @NFTA_NAT_TYPE: NAT type (NLA_U32: nft_nat_types)
* @NFTA_NAT_ADDR_MIN: source register of address range start (NLA_U32: nft_registers) * @NFTA_NAT_FAMILY: NAT family (NLA_U32)
* @NFTA_NAT_ADDR_MAX: source register of address range end (NLA_U32: nft_registers) * @NFTA_NAT_REG_ADDR_MIN: source register of address range start (NLA_U32: nft_registers)
* @NFTA_NAT_PROTO_MIN: source register of proto range start (NLA_U32: nft_registers) * @NFTA_NAT_REG_ADDR_MAX: source register of address range end (NLA_U32: nft_registers)
* @NFTA_NAT_PROTO_MAX: source register of proto range end (NLA_U32: nft_registers) * @NFTA_NAT_REG_PROTO_MIN: source register of proto range start (NLA_U32: nft_registers)
* @NFTA_NAT_REG_PROTO_MAX: source register of proto range end (NLA_U32: nft_registers)
*/ */
enum nft_nat_attributes { enum nft_nat_attributes {
NFTA_NAT_UNSPEC, NFTA_NAT_UNSPEC,
NFTA_NAT_TYPE, NFTA_NAT_TYPE,
NFTA_NAT_ADDR_MIN, NFTA_NAT_FAMILY,
NFTA_NAT_ADDR_MAX, NFTA_NAT_REG_ADDR_MIN,
NFTA_NAT_PROTO_MIN, NFTA_NAT_REG_ADDR_MAX,
NFTA_NAT_PROTO_MAX, NFTA_NAT_REG_PROTO_MIN,
NFTA_NAT_REG_PROTO_MAX,
__NFTA_NAT_MAX __NFTA_NAT_MAX
}; };
#define NFTA_NAT_MAX (__NFTA_NAT_MAX - 1) #define NFTA_NAT_MAX (__NFTA_NAT_MAX - 1)

1
net/ipv4/netfilter/Kconfig
View File

@ -50,6 +50,7 @@ config NFT_CHAIN_ROUTE_IPV4
config NFT_CHAIN_NAT_IPV4 config NFT_CHAIN_NAT_IPV4
depends on NF_TABLES_IPV4 depends on NF_TABLES_IPV4
depends on NF_NAT_IPV4 && NFT_NAT
tristate "IPv4 nf_tables nat chain support" tristate "IPv4 nf_tables nat chain support"
config IP_NF_IPTABLES config IP_NF_IPTABLES

156
net/ipv4/netfilter/nft_chain_nat_ipv4.c
View File

@ -1,6 +1,7 @@
/* /*
* Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net> * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
* Copyright (c) 2012 Pablo Neira Ayuso <pablo@netfilter.org> * Copyright (c) 2012 Pablo Neira Ayuso <pablo@netfilter.org>
* Copyright (c) 2012 Intel Corporation
* *
* This program is free software; you can redistribute it and/or modify * 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 * it under the terms of the GNU General Public License version 2 as
@ -14,10 +15,8 @@
#include <linux/list.h> #include <linux/list.h>
#include <linux/skbuff.h> #include <linux/skbuff.h>
#include <linux/ip.h> #include <linux/ip.h>
#include <linux/netlink.h>
#include <linux/netfilter.h> #include <linux/netfilter.h>
#include <linux/netfilter_ipv4.h> #include <linux/netfilter_ipv4.h>
#include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/nf_tables.h> #include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_conntrack.h> #include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_nat.h> #include <net/netfilter/nf_nat.h>
@ -27,147 +26,6 @@
#include <net/netfilter/nf_nat_l3proto.h> #include <net/netfilter/nf_nat_l3proto.h>
#include <net/ip.h> #include <net/ip.h>
struct nft_nat {
enum nft_registers sreg_addr_min:8;
enum nft_registers sreg_addr_max:8;
enum nft_registers sreg_proto_min:8;
enum nft_registers sreg_proto_max:8;
enum nf_nat_manip_type type;
};
static void nft_nat_eval(const struct nft_expr *expr,
struct nft_data data[NFT_REG_MAX + 1],
const struct nft_pktinfo *pkt)
{
const struct nft_nat *priv = nft_expr_priv(expr);
enum ip_conntrack_info ctinfo;
struct nf_conn *ct = nf_ct_get(pkt->skb, &ctinfo);
struct nf_nat_range range;
memset(&range, 0, sizeof(range));
if (priv->sreg_addr_min) {
range.min_addr.ip = data[priv->sreg_addr_min].data[0];
range.max_addr.ip = data[priv->sreg_addr_max].data[0];
range.flags |= NF_NAT_RANGE_MAP_IPS;
}
if (priv->sreg_proto_min) {
range.min_proto.all = data[priv->sreg_proto_min].data[0];
range.max_proto.all = data[priv->sreg_proto_max].data[0];
range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
}
data[NFT_REG_VERDICT].verdict =
nf_nat_setup_info(ct, &range, priv->type);
}
static const struct nla_policy nft_nat_policy[NFTA_NAT_MAX + 1] = {
[NFTA_NAT_ADDR_MIN] = { .type = NLA_U32 },
[NFTA_NAT_ADDR_MAX] = { .type = NLA_U32 },
[NFTA_NAT_PROTO_MIN] = { .type = NLA_U32 },
[NFTA_NAT_PROTO_MAX] = { .type = NLA_U32 },
[NFTA_NAT_TYPE] = { .type = NLA_U32 },
};
static int nft_nat_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
const struct nlattr * const tb[])
{
struct nft_nat *priv = nft_expr_priv(expr);
int err;
if (tb[NFTA_NAT_TYPE] == NULL)
return -EINVAL;
switch (ntohl(nla_get_be32(tb[NFTA_NAT_TYPE]))) {
case NFT_NAT_SNAT:
priv->type = NF_NAT_MANIP_SRC;
break;
case NFT_NAT_DNAT:
priv->type = NF_NAT_MANIP_DST;
break;
default:
return -EINVAL;
}
if (tb[NFTA_NAT_ADDR_MIN]) {
priv->sreg_addr_min = ntohl(nla_get_be32(tb[NFTA_NAT_ADDR_MIN]));
err = nft_validate_input_register(priv->sreg_addr_min);
if (err < 0)
return err;
}
if (tb[NFTA_NAT_ADDR_MAX]) {
priv->sreg_addr_max = ntohl(nla_get_be32(tb[NFTA_NAT_ADDR_MAX]));
err = nft_validate_input_register(priv->sreg_addr_max);
if (err < 0)
return err;
} else
priv->sreg_addr_max = priv->sreg_addr_min;
if (tb[NFTA_NAT_PROTO_MIN]) {
priv->sreg_proto_min = ntohl(nla_get_be32(tb[NFTA_NAT_PROTO_MIN]));
err = nft_validate_input_register(priv->sreg_proto_min);
if (err < 0)
return err;
}
if (tb[NFTA_NAT_PROTO_MAX]) {
priv->sreg_proto_max = ntohl(nla_get_be32(tb[NFTA_NAT_PROTO_MAX]));
err = nft_validate_input_register(priv->sreg_proto_max);
if (err < 0)
return err;
} else
priv->sreg_proto_max = priv->sreg_proto_min;
return 0;
}
static int nft_nat_dump(struct sk_buff *skb, const struct nft_expr *expr)
{
const struct nft_nat *priv = nft_expr_priv(expr);
switch (priv->type) {
case NF_NAT_MANIP_SRC:
if (nla_put_be32(skb, NFTA_NAT_TYPE, htonl(NFT_NAT_SNAT)))
goto nla_put_failure;
break;
case NF_NAT_MANIP_DST:
if (nla_put_be32(skb, NFTA_NAT_TYPE, htonl(NFT_NAT_DNAT)))
goto nla_put_failure;
break;
}
if (nla_put_be32(skb, NFTA_NAT_ADDR_MIN, htonl(priv->sreg_addr_min)))
goto nla_put_failure;
if (nla_put_be32(skb, NFTA_NAT_ADDR_MAX, htonl(priv->sreg_addr_max)))
goto nla_put_failure;
if (nla_put_be32(skb, NFTA_NAT_PROTO_MIN, htonl(priv->sreg_proto_min)))
goto nla_put_failure;
if (nla_put_be32(skb, NFTA_NAT_PROTO_MAX, htonl(priv->sreg_proto_max)))
goto nla_put_failure;
return 0;
nla_put_failure:
return -1;
}
static struct nft_expr_type nft_nat_type;
static const struct nft_expr_ops nft_nat_ops = {
.type = &nft_nat_type,
.size = NFT_EXPR_SIZE(sizeof(struct nft_nat)),
.eval = nft_nat_eval,
.init = nft_nat_init,
.dump = nft_nat_dump,
};
static struct nft_expr_type nft_nat_type __read_mostly = {
.name = "nat",
.ops = &nft_nat_ops,
.policy = nft_nat_policy,
.maxattr = NFTA_NAT_MAX,
.owner = THIS_MODULE,
};
/* /*
* NAT chains * NAT chains
*/ */
@ -306,7 +164,7 @@ static unsigned int nf_nat_output(const struct nf_hook_ops *ops,
return ret; return ret;
} }
struct nf_chain_type nft_chain_nat_ipv4 = { static struct nf_chain_type nft_chain_nat_ipv4 = {
.family = NFPROTO_IPV4, .family = NFPROTO_IPV4,
.name = "nat", .name = "nat",
.type = NFT_CHAIN_T_NAT, .type = NFT_CHAIN_T_NAT,
@ -331,20 +189,11 @@ static int __init nft_chain_nat_init(void)
if (err < 0) if (err < 0)
return err; return err;
err = nft_register_expr(&nft_nat_type);
if (err < 0)
goto err;
return 0; return 0;
err:
nft_unregister_chain_type(&nft_chain_nat_ipv4);
return err;
} }
static void __exit nft_chain_nat_exit(void) static void __exit nft_chain_nat_exit(void)
{ {
nft_unregister_expr(&nft_nat_type);
nft_unregister_chain_type(&nft_chain_nat_ipv4); nft_unregister_chain_type(&nft_chain_nat_ipv4);
} }
@ -354,4 +203,3 @@ module_exit(nft_chain_nat_exit);
MODULE_LICENSE("GPL"); MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_ALIAS_NFT_CHAIN(AF_INET, "nat"); MODULE_ALIAS_NFT_CHAIN(AF_INET, "nat");
MODULE_ALIAS_NFT_EXPR("nat");

5
net/ipv6/netfilter/Kconfig
View File

@ -33,6 +33,11 @@ config NFT_CHAIN_ROUTE_IPV6
depends on NF_TABLES_IPV6 depends on NF_TABLES_IPV6
tristate "IPv6 nf_tables route chain support" tristate "IPv6 nf_tables route chain support"
config NFT_CHAIN_NAT_IPV6
depends on NF_TABLES_IPV6
depends on NF_NAT_IPV6 && NFT_NAT
tristate "IPv6 nf_tables nat chain support"
config IP6_NF_IPTABLES config IP6_NF_IPTABLES
tristate "IP6 tables support (required for filtering)" tristate "IP6 tables support (required for filtering)"
depends on INET && IPV6 depends on INET && IPV6

1
net/ipv6/netfilter/Makefile
View File

@ -26,6 +26,7 @@ obj-$(CONFIG_NF_DEFRAG_IPV6) += nf_defrag_ipv6.o
# nf_tables # nf_tables
obj-$(CONFIG_NF_TABLES_IPV6) += nf_tables_ipv6.o obj-$(CONFIG_NF_TABLES_IPV6) += nf_tables_ipv6.o
obj-$(CONFIG_NFT_CHAIN_ROUTE_IPV6) += nft_chain_route_ipv6.o obj-$(CONFIG_NFT_CHAIN_ROUTE_IPV6) += nft_chain_route_ipv6.o
obj-$(CONFIG_NFT_CHAIN_NAT_IPV6) += nft_chain_nat_ipv6.o
# matches # matches
obj-$(CONFIG_IP6_NF_MATCH_AH) += ip6t_ah.o obj-$(CONFIG_IP6_NF_MATCH_AH) += ip6t_ah.o

211
net/ipv6/netfilter/nft_chain_nat_ipv6.c Normal file
View File

@ -0,0 +1,211 @@
/*
* Copyright (c) 2011 Patrick McHardy <kaber@trash.net>
* Copyright (c) 2012 Intel Corporation
*
* 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/module.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/skbuff.h>
#include <linux/ip.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv6.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_nat.h>
#include <net/netfilter/nf_nat_core.h>
#include <net/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables_ipv6.h>
#include <net/netfilter/nf_nat_l3proto.h>
#include <net/ipv6.h>
/*
* IPv6 NAT chains
*/
static unsigned int nf_nat_ipv6_fn(const struct nf_hook_ops *ops,
struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
enum ip_conntrack_info ctinfo;
struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
struct nf_conn_nat *nat;
enum nf_nat_manip_type maniptype = HOOK2MANIP(ops->hooknum);
__be16 frag_off;
int hdrlen;
u8 nexthdr;
struct nft_pktinfo pkt;
unsigned int ret;
if (ct == NULL || nf_ct_is_untracked(ct))
return NF_ACCEPT;
nat = nfct_nat(ct);
if (nat == NULL) {
/* Conntrack module was loaded late, can't add extension. */
if (nf_ct_is_confirmed(ct))
return NF_ACCEPT;
nat = nf_ct_ext_add(ct, NF_CT_EXT_NAT, GFP_ATOMIC);
if (nat == NULL)
return NF_ACCEPT;
}
switch (ctinfo) {
case IP_CT_RELATED:
case IP_CT_RELATED + IP_CT_IS_REPLY:
nexthdr = ipv6_hdr(skb)->nexthdr;
hdrlen = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr),
&nexthdr, &frag_off);
if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) {
if (!nf_nat_icmpv6_reply_translation(skb, ct, ctinfo,
ops->hooknum,
hdrlen))
return NF_DROP;
else
return NF_ACCEPT;
}
/* Fall through */
case IP_CT_NEW:
if (nf_nat_initialized(ct, maniptype))
break;
nft_set_pktinfo_ipv6(&pkt, ops, skb, in, out);
ret = nft_do_chain_pktinfo(&pkt, ops);
if (ret != NF_ACCEPT)
return ret;
if (!nf_nat_initialized(ct, maniptype)) {
ret = nf_nat_alloc_null_binding(ct, ops->hooknum);
if (ret != NF_ACCEPT)
return ret;
}
default:
break;
}
return nf_nat_packet(ct, ctinfo, ops->hooknum, skb);
}
static unsigned int nf_nat_ipv6_prerouting(const struct nf_hook_ops *ops,
struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
struct in6_addr daddr = ipv6_hdr(skb)->daddr;
unsigned int ret;
ret = nf_nat_ipv6_fn(ops, skb, in, out, okfn);
if (ret != NF_DROP && ret != NF_STOLEN &&
ipv6_addr_cmp(&daddr, &ipv6_hdr(skb)->daddr))
skb_dst_drop(skb);
return ret;
}
static unsigned int nf_nat_ipv6_postrouting(const struct nf_hook_ops *ops,
struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
enum ip_conntrack_info ctinfo __maybe_unused;
const struct nf_conn *ct __maybe_unused;
unsigned int ret;
ret = nf_nat_ipv6_fn(ops, skb, in, out, okfn);
#ifdef CONFIG_XFRM
if (ret != NF_DROP && ret != NF_STOLEN &&
!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) &&
(ct = nf_ct_get(skb, &ctinfo)) != NULL) {
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
if (!nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.src.u3,
&ct->tuplehash[!dir].tuple.dst.u3) ||
(ct->tuplehash[dir].tuple.src.u.all !=
ct->tuplehash[!dir].tuple.dst.u.all))
if (nf_xfrm_me_harder(skb, AF_INET6) < 0)
ret = NF_DROP;
}
#endif
return ret;
}
static unsigned int nf_nat_ipv6_output(const struct nf_hook_ops *ops,
struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
enum ip_conntrack_info ctinfo;
const struct nf_conn *ct;
unsigned int ret;
ret = nf_nat_ipv6_fn(ops, skb, in, out, okfn);
if (ret != NF_DROP && ret != NF_STOLEN &&
(ct = nf_ct_get(skb, &ctinfo)) != NULL) {
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
if (!nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.dst.u3,
&ct->tuplehash[!dir].tuple.src.u3)) {
if (ip6_route_me_harder(skb))
ret = NF_DROP;
}
#ifdef CONFIG_XFRM
else if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) &&
ct->tuplehash[dir].tuple.dst.u.all !=
ct->tuplehash[!dir].tuple.src.u.all)
if (nf_xfrm_me_harder(skb, AF_INET6))
ret = NF_DROP;
#endif
}
return ret;
}
static struct nf_chain_type nft_chain_nat_ipv6 = {
.family = NFPROTO_IPV6,
.name = "nat",
.type = NFT_CHAIN_T_NAT,
.hook_mask = (1 << NF_INET_PRE_ROUTING) |
(1 << NF_INET_POST_ROUTING) |
(1 << NF_INET_LOCAL_OUT) |
(1 << NF_INET_LOCAL_IN),
.fn = {
[NF_INET_PRE_ROUTING] = nf_nat_ipv6_prerouting,
[NF_INET_POST_ROUTING] = nf_nat_ipv6_postrouting,
[NF_INET_LOCAL_OUT] = nf_nat_ipv6_output,
[NF_INET_LOCAL_IN] = nf_nat_ipv6_fn,
},
.me = THIS_MODULE,
};
static int __init nft_chain_nat_ipv6_init(void)
{
int err;
err = nft_register_chain_type(&nft_chain_nat_ipv6);
if (err < 0)
return err;
return 0;
}
static void __exit nft_chain_nat_ipv6_exit(void)
{
nft_unregister_chain_type(&nft_chain_nat_ipv6);
}
module_init(nft_chain_nat_ipv6_init);
module_exit(nft_chain_nat_ipv6_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>");
MODULE_ALIAS_NFT_CHAIN(AF_INET6, "nat");

6
net/netfilter/Kconfig
View File

@ -450,6 +450,12 @@ config NFT_LIMIT
depends on NF_TABLES depends on NF_TABLES
tristate "Netfilter nf_tables limit module" tristate "Netfilter nf_tables limit module"
config NFT_NAT
depends on NF_TABLES
depends on NF_CONNTRACK
depends on NF_NAT
tristate "Netfilter nf_tables nat module"
config NFT_COMPAT config NFT_COMPAT
depends on NF_TABLES depends on NF_TABLES
depends on NETFILTER_XTABLES depends on NETFILTER_XTABLES

1
net/netfilter/Makefile
View File

@ -75,6 +75,7 @@ obj-$(CONFIG_NFT_EXTHDR) += nft_exthdr.o
obj-$(CONFIG_NFT_META) += nft_meta.o obj-$(CONFIG_NFT_META) += nft_meta.o
obj-$(CONFIG_NFT_CT) += nft_ct.o obj-$(CONFIG_NFT_CT) += nft_ct.o
obj-$(CONFIG_NFT_LIMIT) += nft_limit.o obj-$(CONFIG_NFT_LIMIT) += nft_limit.o
obj-$(CONFIG_NFT_NAT) += nft_nat.o
#nf_tables-objs += nft_meta_target.o #nf_tables-objs += nft_meta_target.o
obj-$(CONFIG_NFT_RBTREE) += nft_rbtree.o obj-$(CONFIG_NFT_RBTREE) += nft_rbtree.o
obj-$(CONFIG_NFT_HASH) += nft_hash.o obj-$(CONFIG_NFT_HASH) += nft_hash.o

220
net/netfilter/nft_nat.c Normal file
View File

@ -0,0 +1,220 @@
/*
* Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
* Copyright (c) 2012 Pablo Neira Ayuso <pablo@netfilter.org>
* Copyright (c) 2012 Intel Corporation
*
* 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/module.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/ip.h>
#include <linux/string.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_nat.h>
#include <net/netfilter/nf_nat_core.h>
#include <net/netfilter/nf_tables.h>
#include <net/netfilter/nf_nat_l3proto.h>
#include <net/ip.h>
struct nft_nat {
enum nft_registers sreg_addr_min:8;
enum nft_registers sreg_addr_max:8;
enum nft_registers sreg_proto_min:8;
enum nft_registers sreg_proto_max:8;
int family;
enum nf_nat_manip_type type;
};
static void nft_nat_eval(const struct nft_expr *expr,
struct nft_data data[NFT_REG_MAX + 1],
const struct nft_pktinfo *pkt)
{
const struct nft_nat *priv = nft_expr_priv(expr);
enum ip_conntrack_info ctinfo;
struct nf_conn *ct = nf_ct_get(pkt->skb, &ctinfo);
struct nf_nat_range range;
memset(&range, 0, sizeof(range));
if (priv->sreg_addr_min) {
if (priv->family == AF_INET) {
range.min_addr.ip = data[priv->sreg_addr_min].data[0];
range.max_addr.ip = data[priv->sreg_addr_max].data[0];
} else {
memcpy(range.min_addr.ip6,
data[priv->sreg_addr_min].data,
sizeof(struct nft_data));
memcpy(range.max_addr.ip6,
data[priv->sreg_addr_max].data,
sizeof(struct nft_data));
}
range.flags |= NF_NAT_RANGE_MAP_IPS;
}
if (priv->sreg_proto_min) {
range.min_proto.all = data[priv->sreg_proto_min].data[0];
range.max_proto.all = data[priv->sreg_proto_max].data[0];
range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
}
data[NFT_REG_VERDICT].verdict =
nf_nat_setup_info(ct, &range, priv->type);
}
static const struct nla_policy nft_nat_policy[NFTA_NAT_MAX + 1] = {
[NFTA_NAT_TYPE] = { .type = NLA_U32 },
[NFTA_NAT_FAMILY] = { .type = NLA_U32 },
[NFTA_NAT_REG_ADDR_MIN] = { .type = NLA_U32 },
[NFTA_NAT_REG_ADDR_MAX] = { .type = NLA_U32 },
[NFTA_NAT_REG_PROTO_MIN] = { .type = NLA_U32 },
[NFTA_NAT_REG_PROTO_MAX] = { .type = NLA_U32 },
};
static int nft_nat_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
const struct nlattr * const tb[])
{
struct nft_nat *priv = nft_expr_priv(expr);
int err;
if (tb[NFTA_NAT_TYPE] == NULL)
return -EINVAL;
switch (ntohl(nla_get_be32(tb[NFTA_NAT_TYPE]))) {
case NFT_NAT_SNAT:
priv->type = NF_NAT_MANIP_SRC;
break;
case NFT_NAT_DNAT:
priv->type = NF_NAT_MANIP_DST;
break;
default:
return -EINVAL;
}
if (tb[NFTA_NAT_FAMILY] == NULL)
return -EINVAL;
priv->family = ntohl(nla_get_be32(tb[NFTA_NAT_FAMILY]));
if (priv->family != AF_INET && priv->family != AF_INET6)
return -EINVAL;
if (tb[NFTA_NAT_REG_ADDR_MIN]) {
priv->sreg_addr_min = ntohl(nla_get_be32(
tb[NFTA_NAT_REG_ADDR_MIN]));
err = nft_validate_input_register(priv->sreg_addr_min);
if (err < 0)
return err;
}
if (tb[NFTA_NAT_REG_ADDR_MAX]) {
priv->sreg_addr_max = ntohl(nla_get_be32(
tb[NFTA_NAT_REG_ADDR_MAX]));
err = nft_validate_input_register(priv->sreg_addr_max);
if (err < 0)
return err;
} else
priv->sreg_addr_max = priv->sreg_addr_min;
if (tb[NFTA_NAT_REG_PROTO_MIN]) {
priv->sreg_proto_min = ntohl(nla_get_be32(
tb[NFTA_NAT_REG_PROTO_MIN]));
err = nft_validate_input_register(priv->sreg_proto_min);
if (err < 0)
return err;
}
if (tb[NFTA_NAT_REG_PROTO_MAX]) {
priv->sreg_proto_max = ntohl(nla_get_be32(
tb[NFTA_NAT_REG_PROTO_MAX]));
err = nft_validate_input_register(priv->sreg_proto_max);
if (err < 0)
return err;
} else
priv->sreg_proto_max = priv->sreg_proto_min;
return 0;
}
static int nft_nat_dump(struct sk_buff *skb, const struct nft_expr *expr)
{
const struct nft_nat *priv = nft_expr_priv(expr);
switch (priv->type) {
case NF_NAT_MANIP_SRC:
if (nla_put_be32(skb, NFTA_NAT_TYPE, htonl(NFT_NAT_SNAT)))
goto nla_put_failure;
break;
case NF_NAT_MANIP_DST:
if (nla_put_be32(skb, NFTA_NAT_TYPE, htonl(NFT_NAT_DNAT)))
goto nla_put_failure;
break;
}
if (nla_put_be32(skb, NFTA_NAT_FAMILY, htonl(priv->family)))
goto nla_put_failure;
if (nla_put_be32(skb,
NFTA_NAT_REG_ADDR_MIN, htonl(priv->sreg_addr_min)))
goto nla_put_failure;
if (nla_put_be32(skb,
NFTA_NAT_REG_ADDR_MAX, htonl(priv->sreg_addr_max)))
goto nla_put_failure;
if (nla_put_be32(skb,
NFTA_NAT_REG_PROTO_MIN, htonl(priv->sreg_proto_min)))
goto nla_put_failure;
if (nla_put_be32(skb,
NFTA_NAT_REG_PROTO_MAX, htonl(priv->sreg_proto_max)))
goto nla_put_failure;
return 0;
nla_put_failure:
return -1;
}
static struct nft_expr_type nft_nat_type;
static const struct nft_expr_ops nft_nat_ops = {
.type = &nft_nat_type,
.size = NFT_EXPR_SIZE(sizeof(struct nft_nat)),
.eval = nft_nat_eval,
.init = nft_nat_init,
.dump = nft_nat_dump,
};
static struct nft_expr_type nft_nat_type __read_mostly = {
.name = "nat",
.ops = &nft_nat_ops,
.policy = nft_nat_policy,
.maxattr = NFTA_NAT_MAX,
.owner = THIS_MODULE,
};
static int __init nft_nat_module_init(void)
{
int err;
err = nft_register_expr(&nft_nat_type);
if (err < 0)
return err;
return 0;
}
static void __exit nft_nat_module_exit(void)
{
nft_unregister_expr(&nft_nat_type);
}
module_init(nft_nat_module_init);
module_exit(nft_nat_module_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>");
MODULE_ALIAS_NFT_EXPR("nat");