Re: [PATCH] gre: copy ToS/DiffServ bits to outer IP header
From: Andreas Jaggi <hidden>
Date: 2009-06-30 09:05:42
Also in:
lkml
Now using the rtnl_link interface.
quoted
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 a per-interface basis. 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
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 2009-06-30 08:22:52.000000000 +0200@@ -34,6 +34,7 @@ __be32 i_key; __be32 o_key; struct iphdr iph; + __u8 copy_tos; }; /* SIT-mode i_flags */
@@ -63,6 +64,7 @@ IFLA_GRE_REMOTE, IFLA_GRE_TTL, IFLA_GRE_TOS, + IFLA_GRE_COPY_TOS, IFLA_GRE_PMTUDISC, __IFLA_GRE_MAX, };
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 2009-06-30 10:48:57.000000000 +0200@@ -677,7 +677,7 @@ } tos = tiph->tos; - if (tos&1) { + if (tunnel->parms.copy_tos || tos&1) { if (skb->protocol == htons(ETH_P_IP)) tos = old_iph->tos; tos &= ~1;
@@ -991,6 +991,7 @@ 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.copy_tos = p.copy_tos; if (t->parms.link != p.link) { t->parms.link = p.link; dev->mtu = ipgre_tunnel_bind_dev(dev);
@@ -1383,6 +1384,9 @@ if (data[IFLA_GRE_TOS]) parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]); + if (data[IFLA_GRE_COPY_TOS]) + parms->copy_tos = nla_get_u8(data[IFLA_GRE_COPY_TOS]); + if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC])) parms->iph.frag_off = htons(IP_DF); }
@@ -1536,6 +1540,8 @@ nla_total_size(1) + /* IFLA_GRE_TOS */ nla_total_size(1) + + /* IFLA_GRE_COPY_TOS */ + nla_total_size(1) + /* IFLA_GRE_PMTUDISC */ nla_total_size(1) + 0;
@@ -1555,6 +1561,7 @@ NLA_PUT_BE32(skb, IFLA_GRE_REMOTE, p->iph.daddr); NLA_PUT_U8(skb, IFLA_GRE_TTL, p->iph.ttl); NLA_PUT_U8(skb, IFLA_GRE_TOS, p->iph.tos); + NLA_PUT_U8(skb, IFLA_GRE_COPY_TOS, p->copy_tos); NLA_PUT_U8(skb, IFLA_GRE_PMTUDISC, !!(p->iph.frag_off & htons(IP_DF))); return 0;
@@ -1573,6 +1580,7 @@ [IFLA_GRE_REMOTE] = { .len = FIELD_SIZEOF(struct iphdr, daddr) }, [IFLA_GRE_TTL] = { .type = NLA_U8 }, [IFLA_GRE_TOS] = { .type = NLA_U8 }, + [IFLA_GRE_COPY_TOS] = { .type = NLA_U8 }, [IFLA_GRE_PMTUDISC] = { .type = NLA_U8 }, };