Re: [PATCH net-next v2 1/2] mpls: allow TTL propagation to IP packets to be configured
From: David Ahern <hidden>
Date: 2017-03-10 02:00:55
On 3/7/17 5:46 PM, Robert Shearman wrote:
quoted hunk ↗ jump to hunk
@@ -244,24 +245,33 @@ static bool mpls_egress(struct mpls_route *rt, struct sk_buff *skb, payload_type = ip_hdr(skb)->version; switch (payload_type) { - case MPT_IPV4: { - struct iphdr *hdr4 = ip_hdr(skb); + case MPT_IPV4: + if (rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED || + (rt->rt_ttl_propagate == MPLS_TTL_PROP_DEFAULT && + net->mpls.ip_ttl_propagate)) { + struct iphdr *hdr4 = ip_hdr(skb); + + csum_replace2(&hdr4->check, + htons(hdr4->ttl << 8), + htons(dec.ttl << 8)); + hdr4->ttl = dec.ttl; + } skb->protocol = htons(ETH_P_IP); - csum_replace2(&hdr4->check, - htons(hdr4->ttl << 8), - htons(dec.ttl << 8)); - hdr4->ttl = dec.ttl; success = true; break; - } - case MPT_IPV6: { - struct ipv6hdr *hdr6 = ipv6_hdr(skb); + case MPT_IPV6: + if (rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED || + (rt->rt_ttl_propagate == MPLS_TTL_PROP_DEFAULT && + net->mpls.ip_ttl_propagate)) { + struct ipv6hdr *hdr6 = ipv6_hdr(skb); + + hdr6->hop_limit = dec.ttl; + } skb->protocol = htons(ETH_P_IPV6); - hdr6->hop_limit = dec.ttl; success = true; break; - }
What decrements the TTL if it is not propagated from MPLS to IP?