Re: [iptables PATCH 06/11] xtables: Do not pass nft_handle to do_parse()

[Pablo Neira Ayuso <pablo@netfilter.org>]

On Mon, Jan 10, 2022 at 10:29:37PM +0100, Pablo Neira Ayuso wrote:
> On Fri, Dec 24, 2021 at 06:17:49PM +0100, Phil Sutter wrote:
> [...]
> > diff --git a/iptables/xshared.h b/iptables/xshared.h
> > index dde94b7335f6a..1954168f64058 100644
> > --- a/iptables/xshared.h
> > +++ b/iptables/xshared.h
> [...]
> >  struct xt_cmd_parse {
> >  	unsigned int			command;
> >  	unsigned int			rulenum;
> > @@ -272,6 +305,11 @@ struct xt_cmd_parse {
> >  	bool				restore;
> >  	int				verbose;
> >  	bool				xlate;
> 
> Probably wrap these two common functions between legacy and nft in a
> structure? Something like: struct nft_parse_ops...

struct xt_parse_ops...

> > +	void		(*proto_parse)(struct iptables_command_state *cs,
> > +				       struct xtables_args *args);
> > +	void		(*post_parse)(int command,
> > +				      struct iptables_command_state *cs,
> > +				      struct xtables_args *args);
> >  };
> >  
> >  #endif /* IPTABLES_XSHARED_H */
> > diff --git a/iptables/xtables-translate.c b/iptables/xtables-translate.c
> > index 9d312b244657e..b0b27695cbb8c 100644
> > --- a/iptables/xtables-translate.c
> > +++ b/iptables/xtables-translate.c
> > @@ -252,6 +252,8 @@ static int do_command_xlate(struct nft_handle *h, int argc, char *argv[],
> >  		.table		= *table,
> >  		.restore	= restore,
> >  		.xlate		= true,
> > +		.proto_parse	= h->ops->proto_parse,
> > +		.post_parse	= h->ops->post_parse,
> 
> so you could just do:
> 
>                 .parse          = h->ops->parse,
> 
> and if you need to extend this structure in the future for whatever
> revolutionary reason, you will need to update this part of the code to
                        ^....
                        you will *not* need

> do:
> 
>                 .another_parse  = h->ops->another_parse,
> 
> Apart from this, anything else LGTM.