netfilter: nft_meta: move all interface related keys to helper

Reduces repetiveness and reduces size of meta eval function.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nft_meta.c b/net/netfilter/nft_meta.c
index 2f7cc64..022f147 100644 (file)
--- a/net/netfilter/nft_meta.c
+++ b/net/netfilter/nft_meta.c
@@ -199,13 +199,79 @@ static noinline bool nft_meta_get_eval_kind(enum nft_meta_keys key,
        return true;
 }
 
+static void nft_meta_store_ifindex(u32 *dest, const struct net_device *dev)
+{
+       *dest = dev ? dev->ifindex : 0;
+}
+
+static void nft_meta_store_ifname(u32 *dest, const struct net_device *dev)
+{
+       strncpy((char *)dest, dev ? dev->name : "", IFNAMSIZ);
+}
+
+static bool nft_meta_store_iftype(u32 *dest, const struct net_device *dev)
+{
+       if (!dev)
+               return false;
+
+       nft_reg_store16(dest, dev->type);
+       return true;
+}
+
+static bool nft_meta_store_ifgroup(u32 *dest, const struct net_device *dev)
+{
+       if (!dev)
+               return false;
+
+       *dest = dev->group;
+       return true;
+}
+
+static bool nft_meta_get_eval_ifname(enum nft_meta_keys key, u32 *dest,
+                                    const struct nft_pktinfo *pkt)
+{
+       switch (key) {
+       case NFT_META_IIFNAME:
+               nft_meta_store_ifname(dest, nft_in(pkt));
+               break;
+       case NFT_META_OIFNAME:
+               nft_meta_store_ifname(dest, nft_out(pkt));
+               break;
+       case NFT_META_IIF:
+               nft_meta_store_ifindex(dest, nft_in(pkt));
+               break;
+       case NFT_META_OIF:
+               nft_meta_store_ifindex(dest, nft_out(pkt));
+               break;
+       case NFT_META_IIFTYPE:
+               if (!nft_meta_store_iftype(dest, nft_in(pkt)))
+                       return false;
+               break;
+       case NFT_META_OIFTYPE:
+               if (!nft_meta_store_iftype(dest, nft_out(pkt)))
+                       return false;
+               break;
+       case NFT_META_IIFGROUP:
+               if (!nft_meta_store_ifgroup(dest, nft_out(pkt)))
+                       return false;
+               break;
+       case NFT_META_OIFGROUP:
+               if (!nft_meta_store_ifgroup(dest, nft_out(pkt)))
+                       return false;
+               break;
+       default:
+               return false;
+       }
+
+       return true;
+}
+
 void nft_meta_get_eval(const struct nft_expr *expr,
                       struct nft_regs *regs,
                       const struct nft_pktinfo *pkt)
 {
        const struct nft_meta *priv = nft_expr_priv(expr);
        const struct sk_buff *skb = pkt->skb;
-       const struct net_device *in = nft_in(pkt), *out = nft_out(pkt);
        u32 *dest = &regs->data[priv->dreg];
 
        switch (priv->key) {
@@ -230,26 +296,15 @@ void nft_meta_get_eval(const struct nft_expr *expr,
                *dest = skb->mark;
                break;
        case NFT_META_IIF:
-               *dest = in ? in->ifindex : 0;
-               break;
        case NFT_META_OIF:
-               *dest = out ? out->ifindex : 0;
-               break;
        case NFT_META_IIFNAME:
-               strncpy((char *)dest, in ? in->name : "", IFNAMSIZ);
-               break;
        case NFT_META_OIFNAME:
-               strncpy((char *)dest, out ? out->name : "", IFNAMSIZ);
-               break;
        case NFT_META_IIFTYPE:
-               if (in == NULL)
-                       goto err;
-               nft_reg_store16(dest, in->type);
-               break;
        case NFT_META_OIFTYPE:
-               if (out == NULL)
+       case NFT_META_IIFGROUP:
+       case NFT_META_OIFGROUP:
+               if (!nft_meta_get_eval_ifname(priv->key, dest, pkt))
                        goto err;
-               nft_reg_store16(dest, out->type);
                break;
        case NFT_META_SKUID:
        case NFT_META_SKGID:
@@ -283,16 +338,6 @@ void nft_meta_get_eval(const struct nft_expr *expr,
        case NFT_META_CPU:
                *dest = raw_smp_processor_id();
                break;
-       case NFT_META_IIFGROUP:
-               if (in == NULL)
-                       goto err;
-               *dest = in->group;
-               break;
-       case NFT_META_OIFGROUP:
-               if (out == NULL)
-                       goto err;
-               *dest = out->group;
-               break;
 #ifdef CONFIG_CGROUP_NET_CLASSID
        case NFT_META_CGROUP:
                if (!nft_meta_get_eval_cgroup(dest, pkt))