[PATCH net-next 1/1] ipv6: remove the destination condition on flow label sharing

[PATCH net-next 1/1] ipv6: remove the destination condition on flow label sharing

[Florent Fourcot]

In case of label sharing, it should be possible to use
one label to more than one destination. This
old restriction is not mandatory, so we can remove it.

Signed-off-by: Florent Fourcot <florent.fourcot@enst-bretagne.fr>
---
 net/ipv6/ip6_flowlabel.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/net/ipv6/ip6_flowlabel.c b/net/ipv6/ip6_flowlabel.c
index 46e8843..f8102d0 100644
--- a/net/ipv6/ip6_flowlabel.c
+++ b/net/ipv6/ip6_flowlabel.c
@@ -604,8 +604,7 @@ recheck:
 					goto release;

 				err = -EINVAL;
-				if (!ipv6_addr_equal(&fl1->dst, &fl->dst) ||
-				    ipv6_opt_cmp(fl1->opt, fl->opt))
+				if (ipv6_opt_cmp(fl1->opt, fl->opt))
 					goto release;

 				err = -ENOMEM;
--
1.8.4.rc3

Re: [PATCH net-next 1/1] ipv6: remove the destination condition on flow label sharing

[Hannes Frederic Sowa]

On Fri, Nov 01, 2013 at 05:11:26PM +0100, Florent Fourcot wrote:
> In case of label sharing, it should be possible to use
> one label to more than one destination. This
> old restriction is not mandatory, so we can remove it.

Why?

Maybe I am not the only one up to date with recent advances in flow label
management but I guess others want to know why, too?

Please reflect this in your changelog.

Greetings,

  Hannes

Re: [PATCH net-next 1/1] ipv6: remove the destination condition on flow label sharing

[Florent Fourcot]

> Why?
> 
> Maybe I am not the only one up to date with recent advances in flow label
> management but I guess others want to know why, too?
> 

Actually, the good question is "why this restriction before". It
probably comes from the RFC 1809, an informational one:

RFC 1809 says:
> 
>    The specification further requires that all datagrams with the same
>    (non-zero) Flow Label must have the same Destination Address, Hop-
>    by-Hop Options header, Routing Header and Source Address contents.

In standard track RFCs (3697 / 6437), there are no restriction to set a
flow label to only one destination. In the same way, the condition on
IPv6 option is obsolete.


> Please reflect this in your changelog.
> 

I will send a V2.