xt: Delay libxtables access until translation

There is no point in spending efforts setting up the xt match/target
when it is not printed afterwards. So just store the statement data from
libnftnl in struct xt_stmt and perform the extension lookup from
xt_stmt_xlate() instead.

This means some data structures are only temporarily allocated for the
sake of passing to libxtables callbacks, no need to drag them around.
Also no need to clone the looked up extension, it is needed only to call
the functions it provides.

While being at it, select numeric output in xt_xlate_*_params -
otherwise there will be reverse DNS lookups which should not happen by
default.

Signed-off-by: Phil Sutter <phil@nwl.cc>

1 files changed, 4 insertions, 5 deletions

diff --git a/include/statement.h b/include/statement.h
index 2a2d3001..8651fc78 100644
--- a/include/statement.h
+++ b/include/statement.h
@@ -264,12 +264,11 @@ struct xtables_target;
 struct xt_stmt {
 	const char			*name;
 	enum nft_xt_type		type;
+	uint32_t			rev;
+	uint32_t			family;
+	size_t				infolen;
+	void				*info;
 	uint32_t			proto;
-	union {
-		struct xtables_match	*match;
-		struct xtables_target	*target;
-	};
-	void				*entry;
 };
 
 extern struct stmt *xt_stmt_alloc(const struct location *loc);