@@ -26,136 +26,53 @@
#include <net/netfilter/nf_nat_l3proto.h>
#include <net/ip.h>
-/*
- * NAT chains
- */
-
-static unsigned int nf_nat_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 *))
+static unsigned int nft_nat_do_chain(const struct nf_hook_ops *ops,
+ struct sk_buff *skb,
+ const struct net_device *in,
+ const struct net_device *out,
+ struct nf_conn *ct)
{
- 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);
struct nft_pktinfo pkt;
- unsigned int ret;
-
- if (ct == NULL || nf_ct_is_untracked(ct))
- return NF_ACCEPT;
-
- NF_CT_ASSERT(!(ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)));
-
- nat = nf_ct_nat_ext_add(ct);
- if (nat == NULL)
- return NF_ACCEPT;
-
- switch (ctinfo) {
- case IP_CT_RELATED:
- case IP_CT_RELATED + IP_CT_IS_REPLY:
- if (ip_hdr(skb)->protocol == IPPROTO_ICMP) {
- if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
- ops->hooknum))
- return NF_DROP;
- else
- return NF_ACCEPT;
- }
- /* Fall through */
- case IP_CT_NEW:
- if (nf_nat_initialized(ct, maniptype))
- break;
- nft_set_pktinfo_ipv4(&pkt, ops, skb, in, out);
+ nft_set_pktinfo_ipv4(&pkt, ops, skb, in, out);
- ret = nft_do_chain(&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);
+ return nft_do_chain(&pkt, ops);
}
-static unsigned int nf_nat_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 *))
+static unsigned int nft_nat_ipv4_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 *))
{
- __be32 daddr = ip_hdr(skb)->daddr;
- unsigned int ret;
-
- ret = nf_nat_fn(ops, skb, in, out, okfn);
- if (ret != NF_DROP && ret != NF_STOLEN &&
- ip_hdr(skb)->daddr != daddr) {
- skb_dst_drop(skb);
- }
- return ret;
+ return nf_nat_ipv4_fn(ops, skb, in, out, nft_nat_do_chain);
}
-static unsigned int nf_nat_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 *))
+static unsigned int nft_nat_ipv4_in(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_fn(ops, skb, in, out, okfn);
-#ifdef CONFIG_XFRM
- 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.src.u3.ip !=
- ct->tuplehash[!dir].tuple.dst.u3.ip ||
- ct->tuplehash[dir].tuple.src.u.all !=
- ct->tuplehash[!dir].tuple.dst.u.all)
- return nf_xfrm_me_harder(skb, AF_INET) == 0 ?
- ret : NF_DROP;
- }
-#endif
- return ret;
+ return nf_nat_ipv4_in(ops, skb, in, out, nft_nat_do_chain);
}
-static unsigned int nf_nat_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 *))
+static unsigned int nft_nat_ipv4_out(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_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);
+ return nf_nat_ipv4_out(ops, skb, in, out, nft_nat_do_chain);
+}
- if (ct->tuplehash[dir].tuple.dst.u3.ip !=
- ct->tuplehash[!dir].tuple.src.u3.ip) {
- if (ip_route_me_harder(skb, RTN_UNSPEC))
- ret = NF_DROP;
- }
-#ifdef CONFIG_XFRM
- else if (ct->tuplehash[dir].tuple.dst.u.all !=
- ct->tuplehash[!dir].tuple.src.u.all)
- if (nf_xfrm_me_harder(skb, AF_INET))
- ret = NF_DROP;
-#endif
- }
- return ret;
+static unsigned int nft_nat_ipv4_local_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 *))
+{
+ return nf_nat_ipv4_local_fn(ops, skb, in, out, nft_nat_do_chain);
}
static const struct nf_chain_type nft_chain_nat_ipv4 = {
@@ -168,10 +85,10 @@ static const struct nf_chain_type nft_chain_nat_ipv4 = {
(1 << NF_INET_LOCAL_OUT) |
(1 << NF_INET_LOCAL_IN),
.hooks = {
- [NF_INET_PRE_ROUTING] = nf_nat_prerouting,
- [NF_INET_POST_ROUTING] = nf_nat_postrouting,
- [NF_INET_LOCAL_OUT] = nf_nat_output,
- [NF_INET_LOCAL_IN] = nf_nat_fn,
+ [NF_INET_PRE_ROUTING] = nft_nat_ipv4_in,
+ [NF_INET_POST_ROUTING] = nft_nat_ipv4_out,
+ [NF_INET_LOCAL_OUT] = nft_nat_ipv4_local_fn,
+ [NF_INET_LOCAL_IN] = nft_nat_ipv4_fn,
},
};
Use the exported IPv4 NAT functions that are provided by the core. This removes duplicated code so iptables and nft use the same NAT codebase. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> --- net/ipv4/netfilter/nft_chain_nat_ipv4.c | 157 ++++++++----------------------- 1 file changed, 37 insertions(+), 120 deletions(-)