From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: Re: [PATCH] gre: copy ToS/DiffServ bits to outer IP header Date: Mon, 13 Jul 2009 08:33:03 -0700 Message-ID: <20090713083303.61a59b63@nehalam> References: <20090713133225.GA20946@urbino.open.ch> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, davem@davemloft.net, kuznet@ms2.inr.ac.ru, kaber@trash.net To: Andreas Jaggi Return-path: Received: from mail.vyatta.com ([76.74.103.46]:48318 "EHLO mail.vyatta.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756202AbZGMPdJ (ORCPT ); Mon, 13 Jul 2009 11:33:09 -0400 In-Reply-To: <20090713133225.GA20946@urbino.open.ch> Sender: netdev-owner@vger.kernel.org List-ID: On Mon, 13 Jul 2009 15:32:25 +0200 Andreas Jaggi wrote: > When tunneling IP traffic with GRE this patch makes it possible to export the > ToS/DiffServ information to the outer IP header. This is particularly useful in > a scenario with ESP/AH where the inner IP header is encrypted but the packet > priority/DiffServ information should still be respected by the transporting > routers (for example in an MPLS backbone network). > > The feature is disabled by default and can be enabled on per-interface basis. > The flag is stored in an unused bit of ip_tunnel_parm.o_flags, and can be > modified through the rntl_link interface. Why make it an option? Sounds like it should always be on. > Also does this bring Linux back in the game, as JunOS/IOS provide this for > quite some time: > http://www.cisco.com/en/US/docs/ios/11_3/feature/guide/greqos.html > http://www.juniper.net/techpubs/software/junos/junos94/swconfig-services/configuring-a-gre-tunnel-to-copy-tos-bits-to-the-outer-ip-header.html > > Signed-off-by: Andreas Jaggi > > diff -urN vanilla-linux-2.6.29.4/include/linux/if_tunnel.h dev-gre/include/linux/if_tunnel.h > --- vanilla-linux-2.6.29.4/include/linux/if_tunnel.h 2009-05-19 01:52:34.000000000 +0200 > +++ dev-gre/include/linux/if_tunnel.h 2009-07-13 15:15:26.000000000 +0200 > @@ -24,6 +24,7 @@ > #define GRE_REC __constant_htons(0x0700) > #define GRE_FLAGS __constant_htons(0x00F8) > #define GRE_VERSION __constant_htons(0x0007) > +#define GRE_COPY_TOS __constant_htons(0x0008) > > struct ip_tunnel_parm > { > diff -urN vanilla-linux-2.6.29.4/net/ipv4/ip_gre.c dev-gre/net/ipv4/ip_gre.c > --- vanilla-linux-2.6.29.4/net/ipv4/ip_gre.c 2009-05-19 01:52:34.000000000 +0200 > +++ dev-gre/net/ipv4/ip_gre.c 2009-07-01 15:30:44.000000000 +0200 > @@ -677,7 +677,7 @@ > } > > tos = tiph->tos; > - if (tos&1) { > + if (tunnel->parms.o_flags&GRE_COPY_TOS || tos&1) { This needs whitespace and parenthesis, to be safe and conform to kernel coding style. > if (skb->protocol == htons(ETH_P_IP)) > tos = old_iph->tos; > tos &= ~1; > @@ -804,7 +804,7 @@ > iph->ttl = dst_metric(&rt->u.dst, RTAX_HOPLIMIT); > } > > - ((__be16 *)(iph + 1))[0] = tunnel->parms.o_flags; > + ((__be16 *)(iph + 1))[0] = tunnel->parms.o_flags&~GRE_FLAGS; more white space > ((__be16 *)(iph + 1))[1] = (dev->type == ARPHRD_ETHER) ? > htons(ETH_P_TEB) : skb->protocol; > > @@ -1080,7 +1080,7 @@ > __be16 *p = (__be16*)(iph+1); > > memcpy(iph, &t->parms.iph, sizeof(struct iphdr)); > - p[0] = t->parms.o_flags; > + p[0] = t->parms.o_flags&~GRE_FLAGS; > p[1] = htons(type); > > /* > @@ -1503,6 +1503,7 @@ > t->parms.iph.ttl = p.iph.ttl; > t->parms.iph.tos = p.iph.tos; > t->parms.iph.frag_off = p.iph.frag_off; > + t->parms.o_flags |= p.o_flags&GRE_COPY_TOS; > > if (t->parms.link != p.link) { > t->parms.link = p.link; > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html --