vxlan: add ttl inherit support
Like tos inherit, ttl inherit should also means inherit the inner protocol's
ttl values, which actually not implemented in vxlan yet.
But we could not treat ttl == 0 as "use the inner TTL", because that would be
used also when the "ttl" option is not specified and that would be a behavior
change, and breaking real use cases.
So add a different attribute IFLA_VXLAN_TTL_INHERIT when "ttl inherit" is
specified with ip cmd.
Reported-by: Jianlin Shi <jishi@redhat.com>
Suggested-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/ip_tunnels.h b/include/net/ip_tunnels.h
index 540a4b4..751646a 100644
--- a/include/net/ip_tunnels.h
+++ b/include/net/ip_tunnels.h
@@ -379,6 +379,17 @@ static inline u8 ip_tunnel_get_dsfield(const struct iphdr *iph,
return 0;
}
+static inline u8 ip_tunnel_get_ttl(const struct iphdr *iph,
+ const struct sk_buff *skb)
+{
+ if (skb->protocol == htons(ETH_P_IP))
+ return iph->ttl;
+ else if (skb->protocol == htons(ETH_P_IPV6))
+ return ((const struct ipv6hdr *)iph)->hop_limit;
+ else
+ return 0;
+}
+
/* Propogate ECN bits out */
static inline u8 ip_tunnel_ecn_encap(u8 tos, const struct iphdr *iph,
const struct sk_buff *skb)
diff --git a/include/net/vxlan.h b/include/net/vxlan.h
index ad73d8b..b99a02ae 100644
--- a/include/net/vxlan.h
+++ b/include/net/vxlan.h
@@ -262,6 +262,7 @@ struct vxlan_dev {
#define VXLAN_F_COLLECT_METADATA 0x2000
#define VXLAN_F_GPE 0x4000
#define VXLAN_F_IPV6_LINKLOCAL 0x8000
+#define VXLAN_F_TTL_INHERIT 0x10000
/* Flags that are used in the receive path. These flags must match in
* order for a socket to be shareable
