netfilter: xtables: use xt_table for hook instantiation

The respective xt_table structures already have most of the metadata
needed for hook setup. Add a 'priority' field to struct xt_table so
that xt_hook_link() can be called with a reduced number of arguments.

So should we be having more tables in the future, it comes at no
static cost (only runtime, as before) - space saved:
6807373->6806555.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/netfilter/x_tables.h b/include/linux/netfilter/x_tables.h
index 365fabe1b16e..fdd3342c1235 100644
--- a/include/linux/netfilter/x_tables.h
+++ b/include/linux/netfilter/x_tables.h
@@ -361,6 +361,7 @@ struct xt_table {
         struct module *me;
 
         u_int8_t af;            /* address/protocol family */
+        int priority;           /* hook order */
 
         /* A unique name... */
         const char name[XT_TABLE_MAXNAMELEN];
@@ -522,6 +523,9 @@ static inline unsigned long ifname_compare_aligned(const char *_a,
         return ret;
 }
 
+extern struct nf_hook_ops *xt_hook_link(const struct xt_table *, nf_hookfn *);
+extern void xt_hook_unlink(const struct xt_table *, struct nf_hook_ops *);
+
 #ifdef CONFIG_COMPAT
 #include <net/compat.h>