net: The world is not perfect patch.
Unless there will be any objection here, I suggest consider the
following patch which simply removes the code for the
-DI_WISH_WORLD_WERE_PERFECT in the three methods which use it.
The compilation errors we get when using -DI_WISH_WORLD_WERE_PERFECT
show that this code was not built and not used for really a long time.
Signed-off-by: Rami Rosen <ramirose@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c
index 149111f..af5cb53 100644
--- a/net/ipv4/ipip.c
+++ b/net/ipv4/ipip.c
@@ -278,9 +278,8 @@
static int ipip_err(struct sk_buff *skb, u32 info)
{
-#ifndef I_WISH_WORLD_WERE_PERFECT
-/* It is not :-( All the routers (except for Linux) return only
+/* 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.
*/
@@ -337,133 +336,6 @@
out:
read_unlock(&ipip_lock);
return err;
-#else
- struct iphdr *iph = (struct iphdr*)dp;
- int hlen = iph->ihl<<2;
- struct iphdr *eiph;
- const int type = icmp_hdr(skb)->type;
- const int code = icmp_hdr(skb)->code;
- int rel_type = 0;
- int rel_code = 0;
- __be32 rel_info = 0;
- __u32 n = 0;
- struct sk_buff *skb2;
- struct flowi fl;
- struct rtable *rt;
-
- if (len < hlen + sizeof(struct iphdr))
- return 0;
- eiph = (struct iphdr*)(dp + hlen);
-
- switch (type) {
- default:
- return 0;
- case ICMP_PARAMETERPROB:
- n = ntohl(icmp_hdr(skb)->un.gateway) >> 24;
- if (n < hlen)
- return 0;
-
- /* So... This guy found something strange INSIDE encapsulated
- packet. Well, he is fool, but what can we do ?
- */
- rel_type = ICMP_PARAMETERPROB;
- rel_info = htonl((n - hlen) << 24);
- break;
-
- case ICMP_DEST_UNREACH:
- switch (code) {
- case ICMP_SR_FAILED:
- case ICMP_PORT_UNREACH:
- /* Impossible event. */
- return 0;
- case ICMP_FRAG_NEEDED:
- /* And it is the only really necessary thing :-) */
- n = ntohs(icmp_hdr(skb)->un.frag.mtu);
- if (n < hlen+68)
- return 0;
- n -= hlen;
- /* BSD 4.2 MORE DOES NOT EXIST IN NATURE. */
- if (n > ntohs(eiph->tot_len))
- return 0;
- rel_info = htonl(n);
- break;
- default:
- /* All others are translated to HOST_UNREACH.
- rfc2003 contains "deep thoughts" about NET_UNREACH,
- I believe, it is just ether pollution. --ANK
- */
- rel_type = ICMP_DEST_UNREACH;
- rel_code = ICMP_HOST_UNREACH;
- break;
- }
- break;
- case ICMP_TIME_EXCEEDED:
- if (code != ICMP_EXC_TTL)
- return 0;
- break;
- }
-
- /* Prepare fake skb to feed it to icmp_send */
- skb2 = skb_clone(skb, GFP_ATOMIC);
- if (skb2 == NULL)
- return 0;
- dst_release(skb2->dst);
- skb2->dst = NULL;
- skb_pull(skb2, skb->data - (u8*)eiph);
- skb_reset_network_header(skb2);
-
- /* Try to guess incoming interface */
- memset(&fl, 0, sizeof(fl));
- fl.fl4_daddr = eiph->saddr;
- fl.fl4_tos = RT_TOS(eiph->tos);
- fl.proto = IPPROTO_IPIP;
- if (ip_route_output_key(dev_net(skb->dev), &rt, &key)) {
- kfree_skb(skb2);
- return 0;
- }
- skb2->dev = rt->u.dst.dev;
-
- /* route "incoming" packet */
- if (rt->rt_flags&RTCF_LOCAL) {
- ip_rt_put(rt);
- rt = NULL;
- fl.fl4_daddr = eiph->daddr;
- fl.fl4_src = eiph->saddr;
- fl.fl4_tos = eiph->tos;
- if (ip_route_output_key(dev_net(skb->dev), &rt, &fl) ||
- rt->u.dst.dev->type != ARPHRD_TUNNEL) {
- ip_rt_put(rt);
- kfree_skb(skb2);
- return 0;
- }
- } else {
- ip_rt_put(rt);
- if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, skb2->dev) ||
- skb2->dst->dev->type != ARPHRD_TUNNEL) {
- kfree_skb(skb2);
- return 0;
- }
- }
-
- /* change mtu on this route */
- if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
- if (n > dst_mtu(skb2->dst)) {
- kfree_skb(skb2);
- return 0;
- }
- skb2->dst->ops->update_pmtu(skb2->dst, n);
- } else if (type == ICMP_TIME_EXCEEDED) {
- struct ip_tunnel *t = netdev_priv(skb2->dev);
- if (t->parms.iph.ttl) {
- rel_type = ICMP_DEST_UNREACH;
- rel_code = ICMP_HOST_UNREACH;
- }
- }
-
- icmp_send(skb2, rel_type, rel_code, rel_info);
- kfree_skb(skb2);
- return 0;
-#endif
}
static inline void ipip_ecn_decapsulate(const struct iphdr *outer_iph,