From b621129f4f08c8d42ac4de2e77a07c5cf0c4b740 Mon Sep 17 00:00:00 2001 From: Vadim Fedorenko Date: Wed, 15 Feb 2017 16:33:56 +0300 Subject: [PATCH] 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 Reviewed-by: Konstantin Khlebnikov Acked-by: Julian Anastasov Signed-off-by: Pablo Neira Ayuso --- net/netfilter/ipvs/ip_vs_xmit.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/net/netfilter/ipvs/ip_vs_xmit.c b/net/netfilter/ipvs/ip_vs_xmit.c index 90d396814798..4527921b1c3a 100644 --- a/net/netfilter/ipvs/ip_vs_xmit.c +++ b/net/netfilter/ipvs/ip_vs_xmit.c @@ -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);