Re: [PATCH] iproute: fix tc generating ipv6 priority filter

[Stephen Hemminger <shemminger@vyatta.com>]

On Mon, 14 Jun 2010 15:36:28 +0200
Petr Lautrbach <plautrba@redhat.com> wrote:

> This patch adds ipv6 filter priority/traffic class function 
> static int parse_ip6_class(int *argc_p, char ***argv_p, struct tc_u32_sel *sel) 
> shifting filter value to 5th bit and ignoring "at" as header position 
> is exactly given.
> 
> Signed-off-by: Petr Lautrbach <plautrba@redhat.com>
> ---
> Hello,
> 
> According to [1], tc doesn't generate right filters for IPv6 
> "priority".
> 
> Priority or Traffic Classes is 8 bits starting at 5th bit 
> based on RFC 2460 [2]. There is parse_u8(&argc, &argv, sel, 4, 0)
> function used in current version, which shifts filter by 4 bytes 
> instead of 4 bits.
> 
> [1] https://bugzilla.redhat.com/show_bug.cgi?id=584913
> [2] http://www.faqs.org/rfcs/rfc2460.html
> 
>  tc/f_u32.c |   39 ++++++++++++++++++++++++++++++++++++++-
>  1 files changed, 38 insertions(+), 1 deletions(-)
> 
> diff --git a/tc/f_u32.c b/tc/f_u32.c
> index 4f5f74e..31e13b5 100644
> --- a/tc/f_u32.c
> +++ b/tc/f_u32.c
> @@ -403,6 +403,43 @@ static int parse_ip6_addr(int *argc_p, char ***argv_p,
>  	return res;
>  }
>  
> +static int parse_ip6_class(int *argc_p, char ***argv_p, struct tc_u32_sel *sel)
> +{
> +	int res = -1;
> +	int argc = *argc_p;
> +	char **argv = *argv_p;
> +	__u32 key;
> +	__u32 mask;
> +	int off = 0;
> +	int offmask = 0;
> +
> +	if (argc < 2)
> +		return -1;
> +
> +	if (get_u32(&key, *argv, 0))
> +		return -1;
> +	argc--; argv++;
> +
> +	if (get_u32(&mask, *argv, 16))
> +		return -1;
> +	argc--; argv++;
> +
> +	if (key > 0xFF || mask > 0xFF)
> +		return -1;
> +
> +	key <<= 20;
> +	mask <<= 20;
> +	key = htonl(key);
> +	mask = htonl(mask);
> +
> +	if (res = pack_key(sel, key, mask, off, offmask) < 0)
> +		return -1;
> +
> +	*argc_p = argc;
> +	*argv_p = argv;
> +	return 0;
> +}
> +
>  static int parse_ether_addr(int *argc_p, char ***argv_p,
>  			    struct tc_u32_sel *sel, int off)
>  {
> @@ -522,7 +559,7 @@ static int parse_ip6(int *argc_p, char ***argv_p, struct tc_u32_sel *sel)
>  		res = parse_ip6_addr(&argc, &argv, sel, 24);
>  	} else if (strcmp(*argv, "priority") == 0) {
>  		NEXT_ARG();
> -		res = parse_u8(&argc, &argv, sel, 4, 0);
> +		res = parse_ip6_class(&argc, &argv, sel);
>  	} else if (strcmp(*argv, "protocol") == 0) {
>  		NEXT_ARG();
>  		res = parse_u8(&argc, &argv, sel, 6, 0);

Applied

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