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[net-next,1/3] ipv4: Multipath hashing on inner L3 needs to consider inner IPv6 pkts

Message ID 20190703151934.9567-2-ssuryaextr@gmail.com
State Changes Requested
Delegated to: David Miller
Headers show
Series net: Multipath hashing on inner L3 | expand

Commit Message

Stephen Suryaputra July 3, 2019, 3:19 p.m. UTC 
Commit 363887a2cdfe ("ipv4: Support multipath hashing on inner IP pkts
for GRE tunnel") supports multipath policy value of 2, Layer 3 or inner
Layer 3 if present, but it only considers inner IPv4. There is a use
case of IPv6 over GRE over IPv4, thus add the ability to hash on inner
IPv6 addresses.

Fixes: 363887a2cdfe ("ipv4: Support multipath hashing on inner IP pkts for GRE tunnel")
Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
---
 net/ipv4/route.c | 21 +++++++++++++++++----
 1 file changed, 17 insertions(+), 4 deletions(-)

Comments

David Miller July 5, 2019, 10:19 p.m. UTC | #1 
From: Stephen Suryaputra <ssuryaextr@gmail.com>
Date: Wed,  3 Jul 2019 11:19:32 -0400

> Commit 363887a2cdfe ("ipv4: Support multipath hashing on inner IP pkts
> for GRE tunnel") supports multipath policy value of 2, Layer 3 or inner
> Layer 3 if present, but it only considers inner IPv4. There is a use
> case of IPv6 over GRE over IPv4, thus add the ability to hash on inner
> IPv6 addresses.
> 
> Fixes: 363887a2cdfe ("ipv4: Support multipath hashing on inner IP pkts for GRE tunnel")
> Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>

The wording in this commit message is very confusing.

If you say "IPv6 over GRE over IPv4" then IPv6 is the outer protocol
type, not the inner one.

You need to clarify or reword this commit message so that it is
understandable and matches the logic.

Thanks.
diff mbox series

Patch

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index dc1f510a7c81..abaa7f9371e5 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1964,17 +1964,30 @@  int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
 		break;
 	case 2:
 		memset(&hash_keys, 0, sizeof(hash_keys));
-		hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
 		/* skb is currently provided only when forwarding */
 		if (skb) {
 			struct flow_keys keys;
 
 			skb_flow_dissect_flow_keys(skb, &keys, 0);
-
-			hash_keys.addrs.v4addrs.src = keys.addrs.v4addrs.src;
-			hash_keys.addrs.v4addrs.dst = keys.addrs.v4addrs.dst;
+			/* Inner can be v4 or v6 */
+			if (keys.control.addr_type == FLOW_DISSECTOR_KEY_IPV4_ADDRS) {
+				hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
+				hash_keys.addrs.v4addrs.src = keys.addrs.v4addrs.src;
+				hash_keys.addrs.v4addrs.dst = keys.addrs.v4addrs.dst;
+			} else if (keys.control.addr_type == FLOW_DISSECTOR_KEY_IPV6_ADDRS) {
+				hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
+				hash_keys.addrs.v6addrs.src = keys.addrs.v6addrs.src;
+				hash_keys.addrs.v6addrs.dst = keys.addrs.v6addrs.dst;
+				hash_keys.tags.flow_label = keys.tags.flow_label;
+				hash_keys.basic.ip_proto = keys.basic.ip_proto;
+			} else {
+				/* Same as case 0 */
+				hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
+				ip_multipath_l3_keys(skb, &hash_keys);
+			}
 		} else {
 			/* Same as case 0 */
+			hash_keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
 			hash_keys.addrs.v4addrs.src = fl4->saddr;
 			hash_keys.addrs.v4addrs.dst = fl4->daddr;
 		}