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Commit 3bf195ae authored by Florian Westphal's avatar Florian Westphal Committed by Pablo Neira Ayuso
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netfilter: nat: merge nf_nat_ipv4,6 into nat core 

before:
   text    data     bss     dec     hex filename
  16566    1576    4136   22278    5706 nf_nat.ko
   3598	    844	      0	   4442	   115a	nf_nat_ipv6.ko
   3187	    844	      0	   4031	    fbf	nf_nat_ipv4.ko

after:
   text    data     bss     dec     hex filename
  22948    1612    4136   28696    7018 nf_nat.ko

... with ipv4/v6 nat now provided directly via nf_nat.ko.

Also changes:
       ret = nf_nat_ipv4_fn(priv, skb, state);
       if (ret != NF_DROP && ret != NF_STOLEN &&
into
	if (ret != NF_ACCEPT)
		return ret;

everywhere.

The nat hooks never should return anything other than
ACCEPT or DROP (and the latter only in rare error cases).

The original code uses multi-line ANDing including assignment-in-if:
        if (ret != NF_DROP && ret != NF_STOLEN &&
           !(IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) &&
            (ct = nf_ct_get(skb, &ctinfo)) != NULL) {

I removed this while moving, breaking those in separate conditionals
and moving the assignments into extra lines.

checkpatch still generates some warnings:
 1. Overly long lines (of moved code).
    Breaking them is even more ugly. so I kept this as-is.
 2. use of extern function declarations in a .c file.
    This is necessary evil, we must call
    nf_nat_l3proto_register() from the nat core now.
    All l3proto related functions are removed later in this series,
    those prototypes are then removed as well.

v2: keep empty nf_nat_ipv6_csum_update stub for CONFIG_IPV6=n case.
v3: remove IS_ENABLED(NF_NAT_IPV4/6) tests, NF_NAT_IPVx toggles
    are removed here.
v4: also get rid of the assignments in conditionals.
Signed-off-by: default avatarFlorian Westphal <fw@strlen.de>
Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
parent 096d0906
Show whitespace changes
Inline Side-by-side
Showing with 711 additions and 738 deletions
net/ipv4/netfilter/Kconfig
View file @ 3bf195ae
...@@ -94,17 +94,7 @@ config NF_REJECT_IPV4 ...@@ -94,17 +94,7 @@ config NF_REJECT_IPV4
tristate "IPv4 packet rejection" tristate "IPv4 packet rejection"
default m if NETFILTER_ADVANCED=n default m if NETFILTER_ADVANCED=n
config NF_NAT_IPV4 if NF_NAT
tristate "IPv4 NAT"
depends on NF_CONNTRACK
default m if NETFILTER_ADVANCED=n
select NF_NAT
help
The IPv4 NAT option allows masquerading, port forwarding and other
forms of full Network Address Port Translation. This can be
controlled by iptables or nft.
if NF_NAT_IPV4
if NF_TABLES if NF_TABLES
config NFT_CHAIN_NAT_IPV4 config NFT_CHAIN_NAT_IPV4
...@@ -163,7 +153,7 @@ config NF_NAT_H323 ...@@ -163,7 +153,7 @@ config NF_NAT_H323
depends on NF_CONNTRACK depends on NF_CONNTRACK
default NF_CONNTRACK_H323 default NF_CONNTRACK_H323
endif # NF_NAT_IPV4 endif # NF_NAT
config IP_NF_IPTABLES config IP_NF_IPTABLES
tristate "IP tables support (required for filtering/masq/NAT)" tristate "IP tables support (required for filtering/masq/NAT)"
...@@ -260,7 +250,6 @@ config IP_NF_NAT ...@@ -260,7 +250,6 @@ config IP_NF_NAT
depends on NF_CONNTRACK depends on NF_CONNTRACK
default m if NETFILTER_ADVANCED=n default m if NETFILTER_ADVANCED=n
select NF_NAT select NF_NAT
select NF_NAT_IPV4
select NETFILTER_XT_NAT select NETFILTER_XT_NAT
help help
This enables the `nat' table in iptables. This allows masquerading, This enables the `nat' table in iptables. This allows masquerading,
......
net/ipv4/netfilter/Makefile
View file @ 3bf195ae
...@@ -3,9 +3,6 @@ ...@@ -3,9 +3,6 @@
# Makefile for the netfilter modules on top of IPv4. # Makefile for the netfilter modules on top of IPv4.
# #
nf_nat_ipv4-y := nf_nat_l3proto_ipv4.o
obj-$(CONFIG_NF_NAT_IPV4) += nf_nat_ipv4.o
# defrag # defrag
obj-$(CONFIG_NF_DEFRAG_IPV4) += nf_defrag_ipv4.o obj-$(CONFIG_NF_DEFRAG_IPV4) += nf_defrag_ipv4.o
......
net/ipv4/netfilter/nf_nat_l3proto_ipv4.c deleted 100644 → 0
View file @ 096d0906
/*
* (C) 1999-2001 Paul `Rusty' Russell
* (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
* (C) 2011 Patrick McHardy <kaber@trash.net>
*
* 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/types.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/ip.h>
#include <linux/icmp.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv4.h>
#include <net/secure_seq.h>
#include <net/checksum.h>
#include <net/route.h>
#include <net/ip.h>
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_nat_core.h>
#include <net/netfilter/nf_nat_l3proto.h>
#include <net/netfilter/nf_nat_l4proto.h>
static const struct nf_nat_l3proto nf_nat_l3proto_ipv4;
static bool nf_nat_ipv4_manip_pkt(struct sk_buff *skb,
unsigned int iphdroff,
const struct nf_conntrack_tuple *target,
enum nf_nat_manip_type maniptype)
{
struct iphdr *iph;
unsigned int hdroff;
if (!skb_make_writable(skb, iphdroff + sizeof(*iph)))
return false;
iph = (void *)skb->data + iphdroff;
hdroff = iphdroff + iph->ihl * 4;
if (!nf_nat_l4proto_manip_pkt(skb, &nf_nat_l3proto_ipv4, iphdroff,
hdroff, target, maniptype))
return false;
iph = (void *)skb->data + iphdroff;
if (maniptype == NF_NAT_MANIP_SRC) {
csum_replace4(&iph->check, iph->saddr, target->src.u3.ip);
iph->saddr = target->src.u3.ip;
} else {
csum_replace4(&iph->check, iph->daddr, target->dst.u3.ip);
iph->daddr = target->dst.u3.ip;
}
return true;
}
static void nf_nat_ipv4_csum_update(struct sk_buff *skb,
unsigned int iphdroff, __sum16 *check,
const struct nf_conntrack_tuple *t,
enum nf_nat_manip_type maniptype)
{
struct iphdr *iph = (struct iphdr *)(skb->data + iphdroff);
__be32 oldip, newip;
if (maniptype == NF_NAT_MANIP_SRC) {
oldip = iph->saddr;
newip = t->src.u3.ip;
} else {
oldip = iph->daddr;
newip = t->dst.u3.ip;
}
inet_proto_csum_replace4(check, skb, oldip, newip, true);
}
static void nf_nat_ipv4_csum_recalc(struct sk_buff *skb,
u8 proto, void *data, __sum16 *check,
int datalen, int oldlen)
{
if (skb->ip_summed != CHECKSUM_PARTIAL) {
const struct iphdr *iph = ip_hdr(skb);
skb->ip_summed = CHECKSUM_PARTIAL;
skb->csum_start = skb_headroom(skb) + skb_network_offset(skb) +
ip_hdrlen(skb);
skb->csum_offset = (void *)check - data;
*check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, datalen,
proto, 0);
} else
inet_proto_csum_replace2(check, skb,
htons(oldlen), htons(datalen), true);
}
static const struct nf_nat_l3proto nf_nat_l3proto_ipv4 = {
.l3proto = NFPROTO_IPV4,
.manip_pkt = nf_nat_ipv4_manip_pkt,
.csum_update = nf_nat_ipv4_csum_update,
.csum_recalc = nf_nat_ipv4_csum_recalc,
};
int nf_nat_icmp_reply_translation(struct sk_buff *skb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned int hooknum)
{
struct {
struct icmphdr icmp;
struct iphdr ip;
} *inside;
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
enum nf_nat_manip_type manip = HOOK2MANIP(hooknum);
unsigned int hdrlen = ip_hdrlen(skb);
struct nf_conntrack_tuple target;
unsigned long statusbit;
WARN_ON(ctinfo != IP_CT_RELATED && ctinfo != IP_CT_RELATED_REPLY);
if (!skb_make_writable(skb, hdrlen + sizeof(*inside)))
return 0;
if (nf_ip_checksum(skb, hooknum, hdrlen, 0))
return 0;
inside = (void *)skb->data + hdrlen;
if (inside->icmp.type == ICMP_REDIRECT) {
if ((ct->status & IPS_NAT_DONE_MASK) != IPS_NAT_DONE_MASK)
return 0;
if (ct->status & IPS_NAT_MASK)
return 0;
}
if (manip == NF_NAT_MANIP_SRC)
statusbit = IPS_SRC_NAT;
else
statusbit = IPS_DST_NAT;
/* Invert if this is reply direction */
if (dir == IP_CT_DIR_REPLY)
statusbit ^= IPS_NAT_MASK;
if (!(ct->status & statusbit))
return 1;
if (!nf_nat_ipv4_manip_pkt(skb, hdrlen + sizeof(inside->icmp),
&ct->tuplehash[!dir].tuple, !manip))
return 0;
if (skb->ip_summed != CHECKSUM_PARTIAL) {
/* Reloading "inside" here since manip_pkt may reallocate */
inside = (void *)skb->data + hdrlen;
inside->icmp.checksum = 0;
inside->icmp.checksum =
csum_fold(skb_checksum(skb, hdrlen,
skb->len - hdrlen, 0));
}
/* Change outer to look like the reply to an incoming packet */
nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple);
target.dst.protonum = IPPROTO_ICMP;
if (!nf_nat_ipv4_manip_pkt(skb, 0, &target, manip))
return 0;
return 1;
}
EXPORT_SYMBOL_GPL(nf_nat_icmp_reply_translation);
static unsigned int
nf_nat_ipv4_fn(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
struct nf_conn *ct;
enum ip_conntrack_info ctinfo;
ct = nf_ct_get(skb, &ctinfo);
if (!ct)
return NF_ACCEPT;
if (ctinfo == IP_CT_RELATED || ctinfo == IP_CT_RELATED_REPLY) {
if (ip_hdr(skb)->protocol == IPPROTO_ICMP) {
if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
state->hook))
return NF_DROP;
else
return NF_ACCEPT;
}
}
return nf_nat_inet_fn(priv, skb, state);
}
static unsigned int
nf_nat_ipv4_in(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
unsigned int ret;
__be32 daddr = ip_hdr(skb)->daddr;
ret = nf_nat_ipv4_fn(priv, skb, state);
if (ret != NF_DROP && ret != NF_STOLEN &&
daddr != ip_hdr(skb)->daddr)
skb_dst_drop(skb);
return ret;
}
static unsigned int
nf_nat_ipv4_out(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
#ifdef CONFIG_XFRM
const struct nf_conn *ct;
enum ip_conntrack_info ctinfo;
int err;
#endif
unsigned int ret;
ret = nf_nat_ipv4_fn(priv, skb, state);
#ifdef CONFIG_XFRM
if (ret != NF_DROP && ret != NF_STOLEN &&
!(IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) &&
(ct = nf_ct_get(skb, &ctinfo)) != NULL) {
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
if ((ct->tuplehash[dir].tuple.src.u3.ip !=
ct->tuplehash[!dir].tuple.dst.u3.ip) ||
(ct->tuplehash[dir].tuple.dst.protonum != IPPROTO_ICMP &&
ct->tuplehash[dir].tuple.src.u.all !=
ct->tuplehash[!dir].tuple.dst.u.all)) {
err = nf_xfrm_me_harder(state->net, skb, AF_INET);
if (err < 0)
ret = NF_DROP_ERR(err);
}
}
#endif
return ret;
}
static unsigned int
nf_nat_ipv4_local_fn(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
const struct nf_conn *ct;
enum ip_conntrack_info ctinfo;
unsigned int ret;
int err;
ret = nf_nat_ipv4_fn(priv, skb, state);
if (ret != NF_DROP && ret != NF_STOLEN &&
(ct = nf_ct_get(skb, &ctinfo)) != NULL) {
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
if (ct->tuplehash[dir].tuple.dst.u3.ip !=
ct->tuplehash[!dir].tuple.src.u3.ip) {
err = ip_route_me_harder(state->net, skb, RTN_UNSPEC);
if (err < 0)
ret = NF_DROP_ERR(err);
}
#ifdef CONFIG_XFRM
else if (!(IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) &&
ct->tuplehash[dir].tuple.dst.protonum != IPPROTO_ICMP &&
ct->tuplehash[dir].tuple.dst.u.all !=
ct->tuplehash[!dir].tuple.src.u.all) {
err = nf_xfrm_me_harder(state->net, skb, AF_INET);
if (err < 0)
ret = NF_DROP_ERR(err);
}
#endif
}
return ret;
}
static const struct nf_hook_ops nf_nat_ipv4_ops[] = {
/* Before packet filtering, change destination */
{
.hook = nf_nat_ipv4_in,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_PRE_ROUTING,
.priority = NF_IP_PRI_NAT_DST,
},
/* After packet filtering, change source */
{
.hook = nf_nat_ipv4_out,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_POST_ROUTING,
.priority = NF_IP_PRI_NAT_SRC,
},
/* Before packet filtering, change destination */
{
.hook = nf_nat_ipv4_local_fn,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_LOCAL_OUT,
.priority = NF_IP_PRI_NAT_DST,
},
/* After packet filtering, change source */
{
.hook = nf_nat_ipv4_fn,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_LOCAL_IN,
.priority = NF_IP_PRI_NAT_SRC,
},
};
int nf_nat_l3proto_ipv4_register_fn(struct net *net, const struct nf_hook_ops *ops)
{
return nf_nat_register_fn(net, ops, nf_nat_ipv4_ops, ARRAY_SIZE(nf_nat_ipv4_ops));
}
EXPORT_SYMBOL_GPL(nf_nat_l3proto_ipv4_register_fn);
void nf_nat_l3proto_ipv4_unregister_fn(struct net *net, const struct nf_hook_ops *ops)
{
nf_nat_unregister_fn(net, ops, ARRAY_SIZE(nf_nat_ipv4_ops));
}
EXPORT_SYMBOL_GPL(nf_nat_l3proto_ipv4_unregister_fn);
static int __init nf_nat_l3proto_ipv4_init(void)
{
return nf_nat_l3proto_register(&nf_nat_l3proto_ipv4);
}
static void __exit nf_nat_l3proto_ipv4_exit(void)
{
nf_nat_l3proto_unregister(&nf_nat_l3proto_ipv4);
}
MODULE_LICENSE("GPL");
MODULE_ALIAS("nf-nat-" __stringify(AF_INET));
module_init(nf_nat_l3proto_ipv4_init);
module_exit(nf_nat_l3proto_ipv4_exit);
net/ipv6/netfilter/Kconfig
View file @ 3bf195ae
...@@ -31,7 +31,7 @@ config NFT_CHAIN_ROUTE_IPV6 ...@@ -31,7 +31,7 @@ config NFT_CHAIN_ROUTE_IPV6
fields such as the source, destination, flowlabel, hop-limit and fields such as the source, destination, flowlabel, hop-limit and
the packet mark. the packet mark.
if NF_NAT_IPV6 if NF_NAT
config NFT_CHAIN_NAT_IPV6 config NFT_CHAIN_NAT_IPV6
tristate "IPv6 nf_tables nat chain support" tristate "IPv6 nf_tables nat chain support"
...@@ -57,7 +57,7 @@ config NFT_REDIR_IPV6 ...@@ -57,7 +57,7 @@ config NFT_REDIR_IPV6
This is the expression that provides IPv4 redirect support for This is the expression that provides IPv4 redirect support for
nf_tables. nf_tables.
endif # NF_NAT_IPV6 endif # NF_NAT
config NFT_REJECT_IPV6 config NFT_REJECT_IPV6
select NF_REJECT_IPV6 select NF_REJECT_IPV6
...@@ -106,16 +106,6 @@ config NF_LOG_IPV6 ...@@ -106,16 +106,6 @@ config NF_LOG_IPV6
default m if NETFILTER_ADVANCED=n default m if NETFILTER_ADVANCED=n
select NF_LOG_COMMON select NF_LOG_COMMON
config NF_NAT_IPV6
tristate "IPv6 NAT"
depends on NF_CONNTRACK
depends on NETFILTER_ADVANCED
select NF_NAT
help
The IPv6 NAT option allows masquerading, port forwarding and other
forms of full Network Address Port Translation. This can be
controlled by iptables or nft.
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
...@@ -304,7 +294,6 @@ config IP6_NF_NAT ...@@ -304,7 +294,6 @@ config IP6_NF_NAT
depends on NF_CONNTRACK depends on NF_CONNTRACK
depends on NETFILTER_ADVANCED depends on NETFILTER_ADVANCED
select NF_NAT select NF_NAT
select NF_NAT_IPV6
select NETFILTER_XT_NAT select NETFILTER_XT_NAT
help help
This enables the `nat' table in ip6tables. This allows masquerading, This enables the `nat' table in ip6tables. This allows masquerading,
......
net/ipv6/netfilter/Makefile
View file @ 3bf195ae
...@@ -11,9 +11,6 @@ obj-$(CONFIG_IP6_NF_RAW) += ip6table_raw.o ...@@ -11,9 +11,6 @@ obj-$(CONFIG_IP6_NF_RAW) += ip6table_raw.o
obj-$(CONFIG_IP6_NF_SECURITY) += ip6table_security.o obj-$(CONFIG_IP6_NF_SECURITY) += ip6table_security.o
obj-$(CONFIG_IP6_NF_NAT) += ip6table_nat.o obj-$(CONFIG_IP6_NF_NAT) += ip6table_nat.o
nf_nat_ipv6-y := nf_nat_l3proto_ipv6.o
obj-$(CONFIG_NF_NAT_IPV6) += nf_nat_ipv6.o
# defrag # defrag
nf_defrag_ipv6-y := nf_defrag_ipv6_hooks.o nf_conntrack_reasm.o nf_defrag_ipv6-y := nf_defrag_ipv6_hooks.o nf_conntrack_reasm.o
obj-$(CONFIG_NF_DEFRAG_IPV6) += nf_defrag_ipv6.o obj-$(CONFIG_NF_DEFRAG_IPV6) += nf_defrag_ipv6.o
......
net/ipv6/netfilter/nf_nat_l3proto_ipv6.c deleted 100644 → 0
View file @ 096d0906
/*
* Copyright (c) 2011 Patrick McHardy <kaber@trash.net>
*
* 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.
*
* Development of IPv6 NAT funded by Astaro.
*/
#include <linux/types.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/ipv6.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv6.h>
#include <net/secure_seq.h>
#include <net/checksum.h>
#include <net/ip6_checksum.h>
#include <net/ip6_route.h>
#include <net/xfrm.h>
#include <net/ipv6.h>
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_nat_core.h>
#include <net/netfilter/nf_nat_l3proto.h>
#include <net/netfilter/nf_nat_l4proto.h>
static const struct nf_nat_l3proto nf_nat_l3proto_ipv6;
static bool nf_nat_ipv6_manip_pkt(struct sk_buff *skb,
unsigned int iphdroff,
const struct nf_conntrack_tuple *target,
enum nf_nat_manip_type maniptype)
{
struct ipv6hdr *ipv6h;
__be16 frag_off;
int hdroff;
u8 nexthdr;
if (!skb_make_writable(skb, iphdroff + sizeof(*ipv6h)))
return false;
ipv6h = (void *)skb->data + iphdroff;
nexthdr = ipv6h->nexthdr;
hdroff = ipv6_skip_exthdr(skb, iphdroff + sizeof(*ipv6h),
&nexthdr, &frag_off);
if (hdroff < 0)
goto manip_addr;
if ((frag_off & htons(~0x7)) == 0 &&
!nf_nat_l4proto_manip_pkt(skb, &nf_nat_l3proto_ipv6, iphdroff, hdroff,
target, maniptype))
return false;
/* must reload, offset might have changed */
ipv6h = (void *)skb->data + iphdroff;
manip_addr:
if (maniptype == NF_NAT_MANIP_SRC)
ipv6h->saddr = target->src.u3.in6;
else
ipv6h->daddr = target->dst.u3.in6;
return true;
}
static void nf_nat_ipv6_csum_update(struct sk_buff *skb,
unsigned int iphdroff, __sum16 *check,
const struct nf_conntrack_tuple *t,
enum nf_nat_manip_type maniptype)
{
const struct ipv6hdr *ipv6h = (struct ipv6hdr *)(skb->data + iphdroff);
const struct in6_addr *oldip, *newip;
if (maniptype == NF_NAT_MANIP_SRC) {
oldip = &ipv6h->saddr;
newip = &t->src.u3.in6;
} else {
oldip = &ipv6h->daddr;
newip = &t->dst.u3.in6;
}
inet_proto_csum_replace16(check, skb, oldip->s6_addr32,
newip->s6_addr32, true);
}
static void nf_nat_ipv6_csum_recalc(struct sk_buff *skb,
u8 proto, void *data, __sum16 *check,
int datalen, int oldlen)
{
if (skb->ip_summed != CHECKSUM_PARTIAL) {
const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
skb->ip_summed = CHECKSUM_PARTIAL;
skb->csum_start = skb_headroom(skb) + skb_network_offset(skb) +
(data - (void *)skb->data);
skb->csum_offset = (void *)check - data;
*check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr,
datalen, proto, 0);
} else
inet_proto_csum_replace2(check, skb,
htons(oldlen), htons(datalen), true);
}
static const struct nf_nat_l3proto nf_nat_l3proto_ipv6 = {
.l3proto = NFPROTO_IPV6,
.manip_pkt = nf_nat_ipv6_manip_pkt,
.csum_update = nf_nat_ipv6_csum_update,
.csum_recalc = nf_nat_ipv6_csum_recalc,
};
int nf_nat_icmpv6_reply_translation(struct sk_buff *skb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned int hooknum,
unsigned int hdrlen)
{
struct {
struct icmp6hdr icmp6;
struct ipv6hdr ip6;
} *inside;
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
enum nf_nat_manip_type manip = HOOK2MANIP(hooknum);
struct nf_conntrack_tuple target;
unsigned long statusbit;
WARN_ON(ctinfo != IP_CT_RELATED && ctinfo != IP_CT_RELATED_REPLY);
if (!skb_make_writable(skb, hdrlen + sizeof(*inside)))
return 0;
if (nf_ip6_checksum(skb, hooknum, hdrlen, IPPROTO_ICMPV6))
return 0;
inside = (void *)skb->data + hdrlen;
if (inside->icmp6.icmp6_type == NDISC_REDIRECT) {
if ((ct->status & IPS_NAT_DONE_MASK) != IPS_NAT_DONE_MASK)
return 0;
if (ct->status & IPS_NAT_MASK)
return 0;
}
if (manip == NF_NAT_MANIP_SRC)
statusbit = IPS_SRC_NAT;
else
statusbit = IPS_DST_NAT;
/* Invert if this is reply direction */
if (dir == IP_CT_DIR_REPLY)
statusbit ^= IPS_NAT_MASK;
if (!(ct->status & statusbit))
return 1;
if (!nf_nat_ipv6_manip_pkt(skb, hdrlen + sizeof(inside->icmp6),
&ct->tuplehash[!dir].tuple, !manip))
return 0;
if (skb->ip_summed != CHECKSUM_PARTIAL) {
struct ipv6hdr *ipv6h = ipv6_hdr(skb);
inside = (void *)skb->data + hdrlen;
inside->icmp6.icmp6_cksum = 0;
inside->icmp6.icmp6_cksum =
csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr,
skb->len - hdrlen, IPPROTO_ICMPV6,
skb_checksum(skb, hdrlen,
skb->len - hdrlen, 0));
}
nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple);
target.dst.protonum = IPPROTO_ICMPV6;
if (!nf_nat_ipv6_manip_pkt(skb, 0, &target, manip))
return 0;
return 1;
}
EXPORT_SYMBOL_GPL(nf_nat_icmpv6_reply_translation);
static unsigned int
nf_nat_ipv6_fn(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
struct nf_conn *ct;
enum ip_conntrack_info ctinfo;
__be16 frag_off;
int hdrlen;
u8 nexthdr;
ct = nf_ct_get(skb, &ctinfo);
/* Can't track? It's not due to stress, or conntrack would
* have dropped it. Hence it's the user's responsibilty to
* packet filter it out, or implement conntrack/NAT for that
* protocol. 8) --RR
*/
if (!ct)
return NF_ACCEPT;
if (ctinfo == IP_CT_RELATED || ctinfo == IP_CT_RELATED_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,
state->hook,
hdrlen))
return NF_DROP;
else
return NF_ACCEPT;
}
}
return nf_nat_inet_fn(priv, skb, state);
}
static unsigned int
nf_nat_ipv6_in(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
unsigned int ret;
struct in6_addr daddr = ipv6_hdr(skb)->daddr;
ret = nf_nat_ipv6_fn(priv, skb, state);
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_out(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
#ifdef CONFIG_XFRM
const struct nf_conn *ct;
enum ip_conntrack_info ctinfo;
int err;
#endif
unsigned int ret;
ret = nf_nat_ipv6_fn(priv, skb, state);
#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.dst.protonum != IPPROTO_ICMPV6 &&
ct->tuplehash[dir].tuple.src.u.all !=
ct->tuplehash[!dir].tuple.dst.u.all)) {
err = nf_xfrm_me_harder(state->net, skb, AF_INET6);
if (err < 0)
ret = NF_DROP_ERR(err);
}
}
#endif
return ret;
}
static int nat_route_me_harder(struct net *net, struct sk_buff *skb)
{
#ifdef CONFIG_IPV6_MODULE
const struct nf_ipv6_ops *v6_ops = nf_get_ipv6_ops();
if (!v6_ops)
return -EHOSTUNREACH;
return v6_ops->route_me_harder(net, skb);
#else
return ip6_route_me_harder(net, skb);
#endif
}
static unsigned int
nf_nat_ipv6_local_fn(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
const struct nf_conn *ct;
enum ip_conntrack_info ctinfo;
unsigned int ret;
int err;
ret = nf_nat_ipv6_fn(priv, skb, state);
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)) {
err = nat_route_me_harder(state->net, skb);
if (err < 0)
ret = NF_DROP_ERR(err);
}
#ifdef CONFIG_XFRM
else if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) &&
ct->tuplehash[dir].tuple.dst.protonum != IPPROTO_ICMPV6 &&
ct->tuplehash[dir].tuple.dst.u.all !=
ct->tuplehash[!dir].tuple.src.u.all) {
err = nf_xfrm_me_harder(state->net, skb, AF_INET6);
if (err < 0)
ret = NF_DROP_ERR(err);
}
#endif
}
return ret;
}
static const struct nf_hook_ops nf_nat_ipv6_ops[] = {
/* Before packet filtering, change destination */
{
.hook = nf_nat_ipv6_in,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_PRE_ROUTING,
.priority = NF_IP6_PRI_NAT_DST,
},
/* After packet filtering, change source */
{
.hook = nf_nat_ipv6_out,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_POST_ROUTING,
.priority = NF_IP6_PRI_NAT_SRC,
},
/* Before packet filtering, change destination */
{
.hook = nf_nat_ipv6_local_fn,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_LOCAL_OUT,
.priority = NF_IP6_PRI_NAT_DST,
},
/* After packet filtering, change source */
{
.hook = nf_nat_ipv6_fn,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_LOCAL_IN,
.priority = NF_IP6_PRI_NAT_SRC,
},
};
int nf_nat_l3proto_ipv6_register_fn(struct net *net, const struct nf_hook_ops *ops)
{
return nf_nat_register_fn(net, ops, nf_nat_ipv6_ops, ARRAY_SIZE(nf_nat_ipv6_ops));
}
EXPORT_SYMBOL_GPL(nf_nat_l3proto_ipv6_register_fn);
void nf_nat_l3proto_ipv6_unregister_fn(struct net *net, const struct nf_hook_ops *ops)
{
nf_nat_unregister_fn(net, ops, ARRAY_SIZE(nf_nat_ipv6_ops));
}
EXPORT_SYMBOL_GPL(nf_nat_l3proto_ipv6_unregister_fn);
static int __init nf_nat_l3proto_ipv6_init(void)
{
return nf_nat_l3proto_register(&nf_nat_l3proto_ipv6);
}
static void __exit nf_nat_l3proto_ipv6_exit(void)
{
nf_nat_l3proto_unregister(&nf_nat_l3proto_ipv6);
}
MODULE_LICENSE("GPL");
MODULE_ALIAS("nf-nat-" __stringify(AF_INET6));
module_init(nf_nat_l3proto_ipv6_init);
module_exit(nf_nat_l3proto_ipv6_exit);
net/netfilter/Kconfig
View file @ 3bf195ae
...@@ -396,7 +396,13 @@ config NETFILTER_NETLINK_GLUE_CT ...@@ -396,7 +396,13 @@ config NETFILTER_NETLINK_GLUE_CT
the enqueued via NFNETLINK. the enqueued via NFNETLINK.
config NF_NAT config NF_NAT
tristate tristate "Network Address Translation support"
depends on NF_CONNTRACK
default m if NETFILTER_ADVANCED=n
help
The NAT option allows masquerading, port forwarding and other
forms of full Network Address Port Translation. This can be
controlled by iptables, ip6tables or nft.
config NF_NAT_NEEDED config NF_NAT_NEEDED
bool bool
......
net/netfilter/nf_nat_core.c
View file @ 3bf195ae
...@@ -1203,6 +1203,8 @@ static struct nf_nat_hook nat_hook = { ...@@ -1203,6 +1203,8 @@ static struct nf_nat_hook nat_hook = {
.manip_pkt = nf_nat_manip_pkt, .manip_pkt = nf_nat_manip_pkt,
}; };
int nf_nat_l3proto_init(void);
void nf_nat_l3proto_exit(void);
static int __init nf_nat_init(void) static int __init nf_nat_init(void)
{ {
int ret, i; int ret, i;
...@@ -1237,6 +1239,19 @@ static int __init nf_nat_init(void) ...@@ -1237,6 +1239,19 @@ static int __init nf_nat_init(void)
WARN_ON(nf_nat_hook != NULL); WARN_ON(nf_nat_hook != NULL);
RCU_INIT_POINTER(nf_nat_hook, &nat_hook); RCU_INIT_POINTER(nf_nat_hook, &nat_hook);
ret = nf_nat_l3proto_init();
if (ret) {
nf_ct_extend_unregister(&nat_extend);
nf_ct_helper_expectfn_unregister(&follow_master_nat);
RCU_INIT_POINTER(nf_nat_hook, NULL);
synchronize_net();
kvfree(nf_nat_bysource);
unregister_pernet_subsys(&nat_net_ops);
return ret;
}
return 0; return 0;
} }
...@@ -1246,6 +1261,8 @@ static void __exit nf_nat_cleanup(void) ...@@ -1246,6 +1261,8 @@ static void __exit nf_nat_cleanup(void)
nf_ct_iterate_destroy(nf_nat_proto_clean, &clean); nf_ct_iterate_destroy(nf_nat_proto_clean, &clean);
nf_nat_l3proto_exit();
nf_ct_extend_unregister(&nat_extend); nf_ct_extend_unregister(&nat_extend);
nf_ct_helper_expectfn_unregister(&follow_master_nat); nf_ct_helper_expectfn_unregister(&follow_master_nat);
RCU_INIT_POINTER(nf_nat_hook, NULL); RCU_INIT_POINTER(nf_nat_hook, NULL);
......
net/netfilter/nf_nat_proto.c
View file @ 3bf195ae
...@@ -24,6 +24,22 @@ ...@@ -24,6 +24,22 @@
#include <net/netfilter/nf_nat_l3proto.h> #include <net/netfilter/nf_nat_l3proto.h>
#include <net/netfilter/nf_nat_l4proto.h> #include <net/netfilter/nf_nat_l4proto.h>
#include <linux/ipv6.h>
#include <linux/netfilter_ipv6.h>
#include <net/checksum.h>
#include <net/ip6_checksum.h>
#include <net/ip6_route.h>
#include <net/xfrm.h>
#include <net/ipv6.h>
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/nf_conntrack.h>
static const struct nf_nat_l3proto nf_nat_l3proto_ipv4;
#if IS_ENABLED(CONFIG_IPV6)
static const struct nf_nat_l3proto nf_nat_l3proto_ipv6;
#endif
static void static void
__udp_manip_pkt(struct sk_buff *skb, __udp_manip_pkt(struct sk_buff *skb,
const struct nf_nat_l3proto *l3proto, const struct nf_nat_l3proto *l3proto,
...@@ -341,3 +357,665 @@ bool nf_nat_l4proto_manip_pkt(struct sk_buff *skb, ...@@ -341,3 +357,665 @@ bool nf_nat_l4proto_manip_pkt(struct sk_buff *skb,
return true; return true;
} }
EXPORT_SYMBOL_GPL(nf_nat_l4proto_manip_pkt); EXPORT_SYMBOL_GPL(nf_nat_l4proto_manip_pkt);
static bool nf_nat_ipv4_manip_pkt(struct sk_buff *skb,
unsigned int iphdroff,
const struct nf_conntrack_tuple *target,
enum nf_nat_manip_type maniptype)
{
struct iphdr *iph;
unsigned int hdroff;
if (!skb_make_writable(skb, iphdroff + sizeof(*iph)))
return false;
iph = (void *)skb->data + iphdroff;
hdroff = iphdroff + iph->ihl * 4;
if (!nf_nat_l4proto_manip_pkt(skb, &nf_nat_l3proto_ipv4, iphdroff,
hdroff, target, maniptype))
return false;
iph = (void *)skb->data + iphdroff;
if (maniptype == NF_NAT_MANIP_SRC) {
csum_replace4(&iph->check, iph->saddr, target->src.u3.ip);
iph->saddr = target->src.u3.ip;
} else {
csum_replace4(&iph->check, iph->daddr, target->dst.u3.ip);
iph->daddr = target->dst.u3.ip;
}
return true;
}
static bool nf_nat_ipv6_manip_pkt(struct sk_buff *skb,
unsigned int iphdroff,
const struct nf_conntrack_tuple *target,
enum nf_nat_manip_type maniptype)
{
#if IS_ENABLED(CONFIG_IPV6)
struct ipv6hdr *ipv6h;
__be16 frag_off;
int hdroff;
u8 nexthdr;
if (!skb_make_writable(skb, iphdroff + sizeof(*ipv6h)))
return false;
ipv6h = (void *)skb->data + iphdroff;
nexthdr = ipv6h->nexthdr;
hdroff = ipv6_skip_exthdr(skb, iphdroff + sizeof(*ipv6h),
&nexthdr, &frag_off);
if (hdroff < 0)
goto manip_addr;
if ((frag_off & htons(~0x7)) == 0 &&
!nf_nat_l4proto_manip_pkt(skb, &nf_nat_l3proto_ipv6, iphdroff, hdroff,
target, maniptype))
return false;
/* must reload, offset might have changed */
ipv6h = (void *)skb->data + iphdroff;
manip_addr:
if (maniptype == NF_NAT_MANIP_SRC)
ipv6h->saddr = target->src.u3.in6;
else
ipv6h->daddr = target->dst.u3.in6;
#endif
return true;
}
static void nf_nat_ipv4_csum_update(struct sk_buff *skb,
unsigned int iphdroff, __sum16 *check,
const struct nf_conntrack_tuple *t,
enum nf_nat_manip_type maniptype)
{
struct iphdr *iph = (struct iphdr *)(skb->data + iphdroff);
__be32 oldip, newip;
if (maniptype == NF_NAT_MANIP_SRC) {
oldip = iph->saddr;
newip = t->src.u3.ip;
} else {
oldip = iph->daddr;
newip = t->dst.u3.ip;
}
inet_proto_csum_replace4(check, skb, oldip, newip, true);
}
static void nf_nat_ipv6_csum_update(struct sk_buff *skb,
unsigned int iphdroff, __sum16 *check,
const struct nf_conntrack_tuple *t,
enum nf_nat_manip_type maniptype)
{
#if IS_ENABLED(CONFIG_IPV6)
const struct ipv6hdr *ipv6h = (struct ipv6hdr *)(skb->data + iphdroff);
const struct in6_addr *oldip, *newip;
if (maniptype == NF_NAT_MANIP_SRC) {
oldip = &ipv6h->saddr;
newip = &t->src.u3.in6;
} else {
oldip = &ipv6h->daddr;
newip = &t->dst.u3.in6;
}
inet_proto_csum_replace16(check, skb, oldip->s6_addr32,
newip->s6_addr32, true);
#endif
}
static void nf_nat_ipv4_csum_recalc(struct sk_buff *skb,
u8 proto, void *data, __sum16 *check,
int datalen, int oldlen)
{
if (skb->ip_summed != CHECKSUM_PARTIAL) {
const struct iphdr *iph = ip_hdr(skb);
skb->ip_summed = CHECKSUM_PARTIAL;
skb->csum_start = skb_headroom(skb) + skb_network_offset(skb) +
ip_hdrlen(skb);
skb->csum_offset = (void *)check - data;
*check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, datalen,
proto, 0);
} else {
inet_proto_csum_replace2(check, skb,
htons(oldlen), htons(datalen), true);
}
}
#if IS_ENABLED(CONFIG_IPV6)
static void nf_nat_ipv6_csum_recalc(struct sk_buff *skb,
u8 proto, void *data, __sum16 *check,
int datalen, int oldlen)
{
if (skb->ip_summed != CHECKSUM_PARTIAL) {
const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
skb->ip_summed = CHECKSUM_PARTIAL;
skb->csum_start = skb_headroom(skb) + skb_network_offset(skb) +
(data - (void *)skb->data);
skb->csum_offset = (void *)check - data;
*check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr,
datalen, proto, 0);
} else {
inet_proto_csum_replace2(check, skb,
htons(oldlen), htons(datalen), true);
}
}
#endif
static const struct nf_nat_l3proto nf_nat_l3proto_ipv4 = {
.l3proto = NFPROTO_IPV4,
.manip_pkt = nf_nat_ipv4_manip_pkt,
.csum_update = nf_nat_ipv4_csum_update,
.csum_recalc = nf_nat_ipv4_csum_recalc,
};
int nf_nat_icmp_reply_translation(struct sk_buff *skb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned int hooknum)
{
struct {
struct icmphdr icmp;
struct iphdr ip;
} *inside;
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
enum nf_nat_manip_type manip = HOOK2MANIP(hooknum);
unsigned int hdrlen = ip_hdrlen(skb);
struct nf_conntrack_tuple target;
unsigned long statusbit;
WARN_ON(ctinfo != IP_CT_RELATED && ctinfo != IP_CT_RELATED_REPLY);
if (!skb_make_writable(skb, hdrlen + sizeof(*inside)))
return 0;
if (nf_ip_checksum(skb, hooknum, hdrlen, 0))
return 0;
inside = (void *)skb->data + hdrlen;
if (inside->icmp.type == ICMP_REDIRECT) {
if ((ct->status & IPS_NAT_DONE_MASK) != IPS_NAT_DONE_MASK)
return 0;
if (ct->status & IPS_NAT_MASK)
return 0;
}
if (manip == NF_NAT_MANIP_SRC)
statusbit = IPS_SRC_NAT;
else
statusbit = IPS_DST_NAT;
/* Invert if this is reply direction */
if (dir == IP_CT_DIR_REPLY)
statusbit ^= IPS_NAT_MASK;
if (!(ct->status & statusbit))
return 1;
if (!nf_nat_ipv4_manip_pkt(skb, hdrlen + sizeof(inside->icmp),
&ct->tuplehash[!dir].tuple, !manip))
return 0;
if (skb->ip_summed != CHECKSUM_PARTIAL) {
/* Reloading "inside" here since manip_pkt may reallocate */
inside = (void *)skb->data + hdrlen;
inside->icmp.checksum = 0;
inside->icmp.checksum =
csum_fold(skb_checksum(skb, hdrlen,
skb->len - hdrlen, 0));
}
/* Change outer to look like the reply to an incoming packet */
nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple);
target.dst.protonum = IPPROTO_ICMP;
if (!nf_nat_ipv4_manip_pkt(skb, 0, &target, manip))
return 0;
return 1;
}
EXPORT_SYMBOL_GPL(nf_nat_icmp_reply_translation);
static unsigned int
nf_nat_ipv4_fn(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
struct nf_conn *ct;
enum ip_conntrack_info ctinfo;
ct = nf_ct_get(skb, &ctinfo);
if (!ct)
return NF_ACCEPT;
if (ctinfo == IP_CT_RELATED || ctinfo == IP_CT_RELATED_REPLY) {
if (ip_hdr(skb)->protocol == IPPROTO_ICMP) {
if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
state->hook))
return NF_DROP;
else
return NF_ACCEPT;
}
}
return nf_nat_inet_fn(priv, skb, state);
}
static unsigned int
nf_nat_ipv4_in(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
unsigned int ret;
__be32 daddr = ip_hdr(skb)->daddr;
ret = nf_nat_ipv4_fn(priv, skb, state);
if (ret == NF_ACCEPT && daddr != ip_hdr(skb)->daddr)
skb_dst_drop(skb);
return ret;
}
static unsigned int
nf_nat_ipv4_out(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
#ifdef CONFIG_XFRM
const struct nf_conn *ct;
enum ip_conntrack_info ctinfo;
int err;
#endif
unsigned int ret;
ret = nf_nat_ipv4_fn(priv, skb, state);
#ifdef CONFIG_XFRM
if (ret != NF_ACCEPT)
return ret;
if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
return ret;
ct = nf_ct_get(skb, &ctinfo);
if (ct) {
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
if (ct->tuplehash[dir].tuple.src.u3.ip !=
ct->tuplehash[!dir].tuple.dst.u3.ip ||
(ct->tuplehash[dir].tuple.dst.protonum != IPPROTO_ICMP &&
ct->tuplehash[dir].tuple.src.u.all !=
ct->tuplehash[!dir].tuple.dst.u.all)) {
err = nf_xfrm_me_harder(state->net, skb, AF_INET);
if (err < 0)
ret = NF_DROP_ERR(err);
}
}
#endif
return ret;
}
static unsigned int
nf_nat_ipv4_local_fn(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
const struct nf_conn *ct;
enum ip_conntrack_info ctinfo;
unsigned int ret;
int err;
ret = nf_nat_ipv4_fn(priv, skb, state);
if (ret != NF_ACCEPT)
return ret;
ct = nf_ct_get(skb, &ctinfo);
if (ct) {
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
if (ct->tuplehash[dir].tuple.dst.u3.ip !=
ct->tuplehash[!dir].tuple.src.u3.ip) {
err = ip_route_me_harder(state->net, skb, RTN_UNSPEC);
if (err < 0)
ret = NF_DROP_ERR(err);
}
#ifdef CONFIG_XFRM
else if (!(IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED) &&
ct->tuplehash[dir].tuple.dst.protonum != IPPROTO_ICMP &&
ct->tuplehash[dir].tuple.dst.u.all !=
ct->tuplehash[!dir].tuple.src.u.all) {
err = nf_xfrm_me_harder(state->net, skb, AF_INET);
if (err < 0)
ret = NF_DROP_ERR(err);
}
#endif
}
return ret;
}
static const struct nf_hook_ops nf_nat_ipv4_ops[] = {
/* Before packet filtering, change destination */
{
.hook = nf_nat_ipv4_in,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_PRE_ROUTING,
.priority = NF_IP_PRI_NAT_DST,
},
/* After packet filtering, change source */
{
.hook = nf_nat_ipv4_out,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_POST_ROUTING,
.priority = NF_IP_PRI_NAT_SRC,
},
/* Before packet filtering, change destination */
{
.hook = nf_nat_ipv4_local_fn,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_LOCAL_OUT,
.priority = NF_IP_PRI_NAT_DST,
},
/* After packet filtering, change source */
{
.hook = nf_nat_ipv4_fn,
.pf = NFPROTO_IPV4,
.hooknum = NF_INET_LOCAL_IN,
.priority = NF_IP_PRI_NAT_SRC,
},
};
int nf_nat_l3proto_ipv4_register_fn(struct net *net, const struct nf_hook_ops *ops)
{
return nf_nat_register_fn(net, ops, nf_nat_ipv4_ops, ARRAY_SIZE(nf_nat_ipv4_ops));
}
EXPORT_SYMBOL_GPL(nf_nat_l3proto_ipv4_register_fn);
void nf_nat_l3proto_ipv4_unregister_fn(struct net *net, const struct nf_hook_ops *ops)
{
nf_nat_unregister_fn(net, ops, ARRAY_SIZE(nf_nat_ipv4_ops));
}
EXPORT_SYMBOL_GPL(nf_nat_l3proto_ipv4_unregister_fn);
int nf_nat_l3proto_init(void)
{
int ret = nf_nat_l3proto_register(&nf_nat_l3proto_ipv4);
#if IS_ENABLED(CONFIG_IPV6)
if (ret)
return ret;
ret = nf_nat_l3proto_register(&nf_nat_l3proto_ipv6);
if (ret == 0)
return ret;
nf_nat_l3proto_unregister(&nf_nat_l3proto_ipv4);
#endif
return ret;
}
void nf_nat_l3proto_exit(void)
{
#if IS_ENABLED(CONFIG_IPV6)
nf_nat_l3proto_unregister(&nf_nat_l3proto_ipv6);
#endif
nf_nat_l3proto_unregister(&nf_nat_l3proto_ipv4);
}
#if IS_ENABLED(CONFIG_IPV6)
static const struct nf_nat_l3proto nf_nat_l3proto_ipv6;
static const struct nf_nat_l3proto nf_nat_l3proto_ipv6 = {
.l3proto = NFPROTO_IPV6,
.manip_pkt = nf_nat_ipv6_manip_pkt,
.csum_update = nf_nat_ipv6_csum_update,
.csum_recalc = nf_nat_ipv6_csum_recalc,
};
int nf_nat_icmpv6_reply_translation(struct sk_buff *skb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned int hooknum,
unsigned int hdrlen)
{
struct {
struct icmp6hdr icmp6;
struct ipv6hdr ip6;
} *inside;
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
enum nf_nat_manip_type manip = HOOK2MANIP(hooknum);
struct nf_conntrack_tuple target;
unsigned long statusbit;
WARN_ON(ctinfo != IP_CT_RELATED && ctinfo != IP_CT_RELATED_REPLY);
if (!skb_make_writable(skb, hdrlen + sizeof(*inside)))
return 0;
if (nf_ip6_checksum(skb, hooknum, hdrlen, IPPROTO_ICMPV6))
return 0;
inside = (void *)skb->data + hdrlen;
if (inside->icmp6.icmp6_type == NDISC_REDIRECT) {
if ((ct->status & IPS_NAT_DONE_MASK) != IPS_NAT_DONE_MASK)
return 0;
if (ct->status & IPS_NAT_MASK)
return 0;
}
if (manip == NF_NAT_MANIP_SRC)
statusbit = IPS_SRC_NAT;
else
statusbit = IPS_DST_NAT;
/* Invert if this is reply direction */
if (dir == IP_CT_DIR_REPLY)
statusbit ^= IPS_NAT_MASK;
if (!(ct->status & statusbit))
return 1;
if (!nf_nat_ipv6_manip_pkt(skb, hdrlen + sizeof(inside->icmp6),
&ct->tuplehash[!dir].tuple, !manip))
return 0;
if (skb->ip_summed != CHECKSUM_PARTIAL) {
struct ipv6hdr *ipv6h = ipv6_hdr(skb);
inside = (void *)skb->data + hdrlen;
inside->icmp6.icmp6_cksum = 0;
inside->icmp6.icmp6_cksum =
csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr,
skb->len - hdrlen, IPPROTO_ICMPV6,
skb_checksum(skb, hdrlen,
skb->len - hdrlen, 0));
}
nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple);
target.dst.protonum = IPPROTO_ICMPV6;
if (!nf_nat_ipv6_manip_pkt(skb, 0, &target, manip))
return 0;
return 1;
}
EXPORT_SYMBOL_GPL(nf_nat_icmpv6_reply_translation);
static unsigned int
nf_nat_ipv6_fn(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
struct nf_conn *ct;
enum ip_conntrack_info ctinfo;
__be16 frag_off;
int hdrlen;
u8 nexthdr;
ct = nf_ct_get(skb, &ctinfo);
/* Can't track? It's not due to stress, or conntrack would
* have dropped it. Hence it's the user's responsibilty to
* packet filter it out, or implement conntrack/NAT for that
* protocol. 8) --RR
*/
if (!ct)
return NF_ACCEPT;
if (ctinfo == IP_CT_RELATED || ctinfo == IP_CT_RELATED_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,
state->hook,
hdrlen))
return NF_DROP;
else
return NF_ACCEPT;
}
}
return nf_nat_inet_fn(priv, skb, state);
}
static unsigned int
nf_nat_ipv6_in(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
unsigned int ret;
struct in6_addr daddr = ipv6_hdr(skb)->daddr;
ret = nf_nat_ipv6_fn(priv, skb, state);
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_out(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
#ifdef CONFIG_XFRM
const struct nf_conn *ct;
enum ip_conntrack_info ctinfo;
int err;
#endif
unsigned int ret;
ret = nf_nat_ipv6_fn(priv, skb, state);
#ifdef CONFIG_XFRM
if (ret != NF_ACCEPT)
return ret;
if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
return ret;
ct = nf_ct_get(skb, &ctinfo);
if (ct) {
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.dst.protonum != IPPROTO_ICMPV6 &&
ct->tuplehash[dir].tuple.src.u.all !=
ct->tuplehash[!dir].tuple.dst.u.all)) {
err = nf_xfrm_me_harder(state->net, skb, AF_INET6);
if (err < 0)
ret = NF_DROP_ERR(err);
}
}
#endif
return ret;
}
static int nat_route_me_harder(struct net *net, struct sk_buff *skb)
{
#ifdef CONFIG_IPV6_MODULE
const struct nf_ipv6_ops *v6_ops = nf_get_ipv6_ops();
if (!v6_ops)
return -EHOSTUNREACH;
return v6_ops->route_me_harder(net, skb);
#else
return ip6_route_me_harder(net, skb);
#endif
}
static unsigned int
nf_nat_ipv6_local_fn(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
{
const struct nf_conn *ct;
enum ip_conntrack_info ctinfo;
unsigned int ret;
int err;
ret = nf_nat_ipv6_fn(priv, skb, state);
if (ret != NF_ACCEPT)
return ret;
ct = nf_ct_get(skb, &ctinfo);
if (ct) {
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
if (!nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.dst.u3,
&ct->tuplehash[!dir].tuple.src.u3)) {
err = nat_route_me_harder(state->net, skb);
if (err < 0)
ret = NF_DROP_ERR(err);
}
#ifdef CONFIG_XFRM
else if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) &&
ct->tuplehash[dir].tuple.dst.protonum != IPPROTO_ICMPV6 &&
ct->tuplehash[dir].tuple.dst.u.all !=
ct->tuplehash[!dir].tuple.src.u.all) {
err = nf_xfrm_me_harder(state->net, skb, AF_INET6);
if (err < 0)
ret = NF_DROP_ERR(err);
}
#endif
}
return ret;
}
static const struct nf_hook_ops nf_nat_ipv6_ops[] = {
/* Before packet filtering, change destination */
{
.hook = nf_nat_ipv6_in,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_PRE_ROUTING,
.priority = NF_IP6_PRI_NAT_DST,
},
/* After packet filtering, change source */
{
.hook = nf_nat_ipv6_out,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_POST_ROUTING,
.priority = NF_IP6_PRI_NAT_SRC,
},
/* Before packet filtering, change destination */
{
.hook = nf_nat_ipv6_local_fn,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_LOCAL_OUT,
.priority = NF_IP6_PRI_NAT_DST,
},
/* After packet filtering, change source */
{
.hook = nf_nat_ipv6_fn,
.pf = NFPROTO_IPV6,
.hooknum = NF_INET_LOCAL_IN,
.priority = NF_IP6_PRI_NAT_SRC,
},
};
int nf_nat_l3proto_ipv6_register_fn(struct net *net, const struct nf_hook_ops *ops)
{
return nf_nat_register_fn(net, ops, nf_nat_ipv6_ops,
ARRAY_SIZE(nf_nat_ipv6_ops));
}
EXPORT_SYMBOL_GPL(nf_nat_l3proto_ipv6_register_fn);
void nf_nat_l3proto_ipv6_unregister_fn(struct net *net, const struct nf_hook_ops *ops)
{
nf_nat_unregister_fn(net, ops, ARRAY_SIZE(nf_nat_ipv6_ops));
}
EXPORT_SYMBOL_GPL(nf_nat_l3proto_ipv6_unregister_fn);
#endif /* CONFIG_IPV6 */
net/openvswitch/Kconfig
View file @ 3bf195ae
...@@ -8,8 +8,6 @@ config OPENVSWITCH ...@@ -8,8 +8,6 @@ config OPENVSWITCH
depends on !NF_CONNTRACK || \ depends on !NF_CONNTRACK || \
(NF_CONNTRACK && ((!NF_DEFRAG_IPV6 || NF_DEFRAG_IPV6) && \ (NF_CONNTRACK && ((!NF_DEFRAG_IPV6 || NF_DEFRAG_IPV6) && \
(!NF_NAT || NF_NAT) && \ (!NF_NAT || NF_NAT) && \
(!NF_NAT_IPV4 || NF_NAT_IPV4) && \
(!NF_NAT_IPV6 || NF_NAT_IPV6) && \
(!NETFILTER_CONNCOUNT || NETFILTER_CONNCOUNT))) (!NETFILTER_CONNCOUNT || NETFILTER_CONNCOUNT)))
select LIBCRC32C select LIBCRC32C
select MPLS select MPLS
......
net/openvswitch/conntrack.c
View file @ 3bf195ae
...@@ -745,14 +745,14 @@ static int ovs_ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct, ...@@ -745,14 +745,14 @@ static int ovs_ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct,
switch (ctinfo) { switch (ctinfo) {
case IP_CT_RELATED: case IP_CT_RELATED:
case IP_CT_RELATED_REPLY: case IP_CT_RELATED_REPLY:
if (IS_ENABLED(CONFIG_NF_NAT_IPV4) && if (IS_ENABLED(CONFIG_NF_NAT) &&
skb->protocol == htons(ETH_P_IP) && skb->protocol == htons(ETH_P_IP) &&
ip_hdr(skb)->protocol == IPPROTO_ICMP) { ip_hdr(skb)->protocol == IPPROTO_ICMP) {
if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo, if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
hooknum)) hooknum))
err = NF_DROP; err = NF_DROP;
goto push; goto push;
} else if (IS_ENABLED(CONFIG_NF_NAT_IPV6) && } else if (IS_ENABLED(CONFIG_IPV6) &&
skb->protocol == htons(ETH_P_IPV6)) { skb->protocol == htons(ETH_P_IPV6)) {
__be16 frag_off; __be16 frag_off;
u8 nexthdr = ipv6_hdr(skb)->nexthdr; u8 nexthdr = ipv6_hdr(skb)->nexthdr;
...@@ -1673,7 +1673,7 @@ static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info, ...@@ -1673,7 +1673,7 @@ static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info,
} }
if (info->range.flags & NF_NAT_RANGE_MAP_IPS) { if (info->range.flags & NF_NAT_RANGE_MAP_IPS) {
if (IS_ENABLED(CONFIG_NF_NAT_IPV4) && if (IS_ENABLED(CONFIG_NF_NAT) &&
info->family == NFPROTO_IPV4) { info->family == NFPROTO_IPV4) {
if (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MIN, if (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MIN,
info->range.min_addr.ip) || info->range.min_addr.ip) ||
...@@ -1682,7 +1682,7 @@ static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info, ...@@ -1682,7 +1682,7 @@ static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info,
(nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MAX, (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MAX,
info->range.max_addr.ip)))) info->range.max_addr.ip))))
return false; return false;
} else if (IS_ENABLED(CONFIG_NF_NAT_IPV6) && } else if (IS_ENABLED(CONFIG_IPV6) &&
info->family == NFPROTO_IPV6) { info->family == NFPROTO_IPV6) {
if (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MIN, if (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MIN,
&info->range.min_addr.in6) || &info->range.min_addr.in6) ||
......
tools/testing/selftests/net/config
View file @ 3bf195ae
...@@ -17,8 +17,7 @@ CONFIG_VLAN_8021Q=y ...@@ -17,8 +17,7 @@ CONFIG_VLAN_8021Q=y
CONFIG_NETFILTER=y CONFIG_NETFILTER=y
CONFIG_NETFILTER_ADVANCED=y CONFIG_NETFILTER_ADVANCED=y
CONFIG_NF_CONNTRACK=m CONFIG_NF_CONNTRACK=m
CONFIG_NF_NAT_IPV6=m CONFIG_NF_NAT=m
CONFIG_NF_NAT_IPV4=m
CONFIG_IP6_NF_IPTABLES=m CONFIG_IP6_NF_IPTABLES=m
CONFIG_IP_NF_IPTABLES=m CONFIG_IP_NF_IPTABLES=m
CONFIG_IP6_NF_NAT=m CONFIG_IP6_NF_NAT=m
......
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