-static int vti_err(struct sk_buff *skb, u32 info)
-{
-
- /* All the routers (except for Linux) return only
- * 8 bytes of packet payload. It means, that precise relaying of
- * ICMP in the real Internet is absolutely infeasible.
- */
- struct net *net = dev_net(skb->dev);
- struct ip_tunnel_net *itn = net_generic(net, vti_net_id);
- struct iphdr *iph = (struct iphdr *)skb->data;
- const int type = icmp_hdr(skb)->type;
- const int code = icmp_hdr(skb)->code;
- struct ip_tunnel *t;
- int err;
-
- switch (type) {
- default:
- case ICMP_PARAMETERPROB:
- return 0;
-
- case ICMP_DEST_UNREACH:
- switch (code) {
- case ICMP_SR_FAILED:
- case ICMP_PORT_UNREACH:
- /* Impossible event. */
- return 0;
- default:
- /* All others are translated to HOST_UNREACH. */
- break;
- }
- break;
- case ICMP_TIME_EXCEEDED:
- if (code != ICMP_EXC_TTL)
- return 0;
- break;
- }
-
- err = -ENOENT;
-
- t = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY,
- iph->daddr, iph->saddr, 0);
- if (t == NULL)
- goto out;
-
- if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
- ipv4_update_pmtu(skb, dev_net(skb->dev), info,
- t->parms.link, 0, IPPROTO_IPIP, 0);
- err = 0;
- goto out;
- }
-
- err = 0;
- if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
- goto out;
-
- if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
- t->err_count++;
- else
- t->err_count = 1;
- t->err_time = jiffies;
-out:
- return err;
-}
-