netfilter: ipvs: full-functionality option for ECN encapsulation in tunnel

IPVS tunnel mode works as simple tunnel (see RFC 3168) copying ECN field
to outer header. That's result in packet drops on egress tunnels in case
the egress tunnel operates as ECN-capable with Full-functionality option
(like ip_tunnel and ip6_tunnel kernel modules), according to RFC 3168
section 9.1.1 recommendation.

This patch implements ECN full-functionality option into ipvs xmit code.

Cc: netdev@vger.kernel.org
Cc: lvs-devel@vger.kernel.org
Signed-off-by: Vadim Fedorenko <vfedorenko@yandex-team.ru>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Vadim Fedorenko 2017-02-15 16:33:56 +03:00 committed by Pablo Neira Ayuso
parent b4391db423
commit b621129f4f
1 changed files with 6 additions and 2 deletions

View File

@ -921,6 +921,7 @@ ip_vs_prepare_tunneled_skb(struct sk_buff *skb, int skb_af,
{
struct sk_buff *new_skb = NULL;
struct iphdr *old_iph = NULL;
__u8 old_dsfield;
#ifdef CONFIG_IP_VS_IPV6
struct ipv6hdr *old_ipv6h = NULL;
#endif
@ -945,7 +946,7 @@ ip_vs_prepare_tunneled_skb(struct sk_buff *skb, int skb_af,
*payload_len =
ntohs(old_ipv6h->payload_len) +
sizeof(*old_ipv6h);
*dsfield = ipv6_get_dsfield(old_ipv6h);
old_dsfield = ipv6_get_dsfield(old_ipv6h);
*ttl = old_ipv6h->hop_limit;
if (df)
*df = 0;
@ -960,12 +961,15 @@ ip_vs_prepare_tunneled_skb(struct sk_buff *skb, int skb_af,
/* fix old IP header checksum */
ip_send_check(old_iph);
*dsfield = ipv4_get_dsfield(old_iph);
old_dsfield = ipv4_get_dsfield(old_iph);
*ttl = old_iph->ttl;
if (payload_len)
*payload_len = ntohs(old_iph->tot_len);
}
/* Implement full-functionality option for ECN encapsulation */
*dsfield = INET_ECN_encapsulate(old_dsfield, old_dsfield);
return skb;
error:
kfree_skb(skb);