[PATCH 6/8] flow_dissector: Use IPv6 flow label in flow_dissector
From: Tom Herbert <hidden>
Date: 2014-07-02 04:33:02
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
This patch implements the receive side to support RFC 6438 which is to use the flow label as an ECMP hash. If an IPv6 flow label is set in a packet we can use this as input for computing an L4-hash. There should be no need to parse any transport headers in this case. Signed-off-by: Tom Herbert <redacted> --- net/core/flow_dissector.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+)
diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index 62d1cb6..c5f3912 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c@@ -80,6 +80,8 @@ ip: case htons(ETH_P_IPV6): { const struct ipv6hdr *iph; struct ipv6hdr _iph; + __be32 flow_label; + ipv6: iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph); if (!iph)
@@ -89,6 +91,21 @@ ipv6: flow->src = (__force __be32)ipv6_addr_hash(&iph->saddr); flow->dst = (__force __be32)ipv6_addr_hash(&iph->daddr); nhoff += sizeof(struct ipv6hdr); + + flow_label = ip6_flowlabel(iph); + if (flow_label) { + /* Awesome, IPv6 packet has a flow label so we can + * use that to represent the ports without any + * further dissection. + */ + flow->n_proto = proto; + flow->ip_proto = ip_proto; + flow->ports = flow_label; + flow->thoff = (u16)nhoff; + + return true; + } + break; } case htons(ETH_P_8021AD):
--
2.0.0.526.g5318336