netfilter: nf_tables: make chain types override the default AF functions

Currently the AF-specific hook functions override the chain-type specific
hook functions. That doesn't make too much sense since the chain types
are a special case of the AF-specific hooks.

Make the AF-specific hook functions the default and make the optional
chain type hooks override them.

As a side effect, the necessary code restructuring reduces the code size,
f.i. in case of nf_tables_ipv4.o:

  nf_tables_ipv4_init_net   |  -24
  nft_do_chain_ipv4         | -113
 2 functions changed, 137 bytes removed, diff: -137

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 20 insertions, 28 deletions

diff --git a/net/ipv6/netfilter/nf_tables_ipv6.c b/net/ipv6/netfilter/nf_tables_ipv6.c
index d77db8a13505..54a2bcdc8a17 100644
--- a/net/ipv6/netfilter/nf_tables_ipv6.c
+++ b/net/ipv6/netfilter/nf_tables_ipv6.c
@@ -16,24 +16,35 @@
 #include <net/netfilter/nf_tables.h>
 #include <net/netfilter/nf_tables_ipv6.h>
 
+static unsigned int nft_do_chain_ipv6(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 nft_pktinfo pkt;
+
+        /* malformed packet, drop it */
+        if (nft_set_pktinfo_ipv6(&pkt, ops, skb, in, out) < 0)
+                return NF_DROP;
+
+        return nft_do_chain_pktinfo(&pkt, ops);
+}
+
 static unsigned int nft_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 *))
 {
-        struct nft_pktinfo pkt;
-
         if (unlikely(skb->len < sizeof(struct ipv6hdr))) {
                 if (net_ratelimit())
                         pr_info("nf_tables_ipv6: ignoring short SOCK_RAW "
                                 "packet\n");
                 return NF_ACCEPT;
         }
-        if (nft_set_pktinfo_ipv6(&pkt, ops, skb, in, out) < 0)
-                return NF_DROP;
 
-        return nft_do_chain_pktinfo(&pkt, ops);
+        return nft_do_chain_ipv6(ops, skb, in, out, okfn);
 }
 
 static struct nft_af_info nft_af_ipv6 __read_mostly = {
@@ -41,7 +52,11 @@ static struct nft_af_info nft_af_ipv6 __read_mostly = {
         .nhooks         = NF_INET_NUMHOOKS,
         .owner          = THIS_MODULE,
         .hooks          = {
+                [NF_INET_LOCAL_IN]      = nft_do_chain_ipv6,
                 [NF_INET_LOCAL_OUT]     = nft_ipv6_output,
+                [NF_INET_FORWARD]       = nft_do_chain_ipv6,
+                [NF_INET_PRE_ROUTING]   = nft_do_chain_ipv6,
+                [NF_INET_POST_ROUTING]  = nft_do_chain_ipv6,
         },
 };
 
@@ -73,22 +88,6 @@ static struct pernet_operations nf_tables_ipv6_net_ops = {
         .exit   = nf_tables_ipv6_exit_net,
 };
 
-static unsigned int
-nft_do_chain_ipv6(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 nft_pktinfo pkt;
-
-        /* malformed packet, drop it */
-        if (nft_set_pktinfo_ipv6(&pkt, ops, skb, in, out) < 0)
-                return NF_DROP;
-
-        return nft_do_chain_pktinfo(&pkt, ops);
-}
-
 static struct nf_chain_type filter_ipv6 = {
         .family         = NFPROTO_IPV6,
         .name           = "filter",
@@ -98,13 +97,6 @@ static struct nf_chain_type filter_ipv6 = {
                           (1 << NF_INET_FORWARD) |
                           (1 << NF_INET_PRE_ROUTING) |
                           (1 << NF_INET_POST_ROUTING),
-        .fn             = {
-                [NF_INET_LOCAL_IN]      = nft_do_chain_ipv6,
-                [NF_INET_LOCAL_OUT]     = nft_ipv6_output,
-                [NF_INET_FORWARD]       = nft_do_chain_ipv6,
-                [NF_INET_PRE_ROUTING]   = nft_do_chain_ipv6,
-                [NF_INET_POST_ROUTING]  = nft_do_chain_ipv6,
-        },
 };
 
 static int __init nf_tables_ipv6_init(void)