Re: [PATCH nft RFC] payload: use ethertype in hexadecimal for meta protocol

[Patrick McHardy <kaber@trash.net>]

On Wed, Jan 15, 2014 at 06:11:42PM +0100, Pablo Neira Ayuso wrote:
> This is a temporary workaround to avoid parsing problems since
> ip and arp are misinterpreted by the parser. It also uses ipv6
> which is different from ip6 and it seems inconsistent to me.

Why not fix it the way we did for TCP/UDP/...?

I agree about the inconsistencies wrt. ipv6 vs. ip6, we should change
all occurences to one of both. Don't really care which one, but I guess
ipv6 is "more correct".

> 
> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
> ---
> A possible alternative to this patch could be to use something
> like: ether-arp ether-ip ether-ipv6 ether-vlan, as these represent
> ethernet protocol types.



> 
>  src/payload.c |   17 +++--------------
>  1 file changed, 3 insertions(+), 14 deletions(-)
> 
> diff --git a/src/payload.c b/src/payload.c
> index 86d75fa..c4ea6da 100644
> --- a/src/payload.c
> +++ b/src/payload.c
> @@ -978,16 +978,6 @@ const struct datatype etheraddr_type = {
>  	.basetype	= &lladdr_type,
>  };
>  
> -static const struct symbol_table ethertype_tbl = {
> -	.symbols	= {
> -		SYMBOL("ip",		ETH_P_IP),
> -		SYMBOL("arp",		ETH_P_ARP),
> -		SYMBOL("ipv6",		ETH_P_IPV6),
> -		SYMBOL("vlan",		ETH_P_8021Q),
> -		SYMBOL_LIST_END
> -	},
> -};
> -
>  static struct error_record *ethertype_parse(const struct expr *sym,
>  					    struct expr **res)
>  {
> @@ -996,14 +986,13 @@ static struct error_record *ethertype_parse(const struct expr *sym,
>  	erec = sym->dtype->basetype->parse(sym, res);
>  	if (erec != NULL)
>  		return erec;
> -	if (*res)
> -		return NULL;
> -	return symbolic_constant_parse(sym, &ethertype_tbl, res);
> +
> +	return NULL;
>  }
>  
>  static void ethertype_print(const struct expr *expr)
>  {
> -	return symbolic_constant_print(&ethertype_tbl, expr);
> +	expr_basetype(expr)->print(expr);
>  }
>  
>  const struct datatype ethertype_type = {
> -- 
> 1.7.10.4