Re: [PATCH] extensions: libxt_helper: Add translation to nft

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

On Wed, Dec 23, 2015 at 03:23:47PM +0530, Shivani Bhardwaj wrote:
> Add translation for helper module to nftables.
> 
> Examples:
> 
> $ sudo iptables-translate -A FORWARD -m helper --helper sip
> nft add rule ip filter FORWARD ct helper \"sip\" counter
> 
> $ sudo iptables-translate -A FORWARD -m helper ! --helper ftp
> nft add rule ip filter FORWARD ct helper != \"ftp\" counter
> 
> Signed-off-by: Shivani Bhardwaj <shivanib134@gmail.com>
> ---
>  extensions/libxt_helper.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/extensions/libxt_helper.c b/extensions/libxt_helper.c
> index c9f9435..5f1d8b1 100644
> --- a/extensions/libxt_helper.c
> +++ b/extensions/libxt_helper.c
> @@ -45,6 +45,19 @@ static void helper_save(const void *ip, const struct xt_entry_match *match)
>  	xtables_save_string(info->name);
>  }
>  
> +static int helper_xlate(const struct xt_entry_match *match,
> +			struct xt_buf *buf, int numeric)
> +{
> +	const struct xt_helper_info *info = (const void *)match->data;
> +
> +	xt_buf_add(buf, "ct helper");
> +
> +	xt_buf_add(buf, "%s \\\"%s\\\" ",
> +		   info->invert ? " !=" : "", info->name);

You can place this in one single call of xt_buf_add(), right?