net: Add full IPv6 addresses to flow_keys

This patch adds full IPv6 addresses into flow_keys and uses them as
input to the flow hash function. The implementation supports either
IPv4 or IPv6 addresses in a union, and selector is used to determine
how may words to input to jhash2.

We also add flow_get_u32_dst and flow_get_u32_src functions which are
used to get a u32 representation of the source and destination
addresses. For IPv6, ipv6_addr_hash is called. These functions retain
getting the legacy values of src and dst in flow_keys.

With this patch, Ethertype and IP protocol are now included in the
flow hash input.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 4 deletions

diff --git a/net/sched/cls_flow.c b/net/sched/cls_flow.c
index b435992..76bc3a2 100644
--- a/net/sched/cls_flow.c
+++ b/net/sched/cls_flow.c
@@ -68,15 +68,21 @@ static inline u32 addr_fold(void *addr)
 
 static u32 flow_get_src(const struct sk_buff *skb, const struct flow_keys *flow)
 {
-	if (flow->addrs.src)
-		return ntohl(flow->addrs.src);
+	__be32 src = flow_get_u32_src(flow);
+
+	if (src)
+		return ntohl(src);
+
 	return addr_fold(skb->sk);
 }
 
 static u32 flow_get_dst(const struct sk_buff *skb, const struct flow_keys *flow)
 {
-	if (flow->addrs.dst)
-		return ntohl(flow->addrs.dst);
+	__be32 dst = flow_get_u32_dst(flow);
+
+	if (dst)
+		return ntohl(dst);
+
 	return addr_fold(skb_dst(skb)) ^ (__force u16) tc_skb_protocol(skb);
 }