diff options
Diffstat (limited to 'net/ipv4/ip_gre.c')
-rw-r--r-- | net/ipv4/ip_gre.c | 146 |
1 files changed, 1 insertions, 145 deletions
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 2ada033406de..4342cba4ff82 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -313,9 +313,8 @@ static void ipgre_tunnel_uninit(struct net_device *dev) static void ipgre_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. @@ -398,149 +397,6 @@ static void ipgre_err(struct sk_buff *skb, u32 info) out: read_unlock(&ipgre_lock); return; -#else - struct iphdr *iph = (struct iphdr*)dp; - struct iphdr *eiph; - __be16 *p = (__be16*)(dp+(iph->ihl<<2)); - 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; - __be16 flags; - int grehlen = (iph->ihl<<2) + 4; - struct sk_buff *skb2; - struct flowi fl; - struct rtable *rt; - - if (p[1] != htons(ETH_P_IP)) - return; - - flags = p[0]; - if (flags&(GRE_CSUM|GRE_KEY|GRE_SEQ|GRE_ROUTING|GRE_VERSION)) { - if (flags&(GRE_VERSION|GRE_ROUTING)) - return; - if (flags&GRE_CSUM) - grehlen += 4; - if (flags&GRE_KEY) - grehlen += 4; - if (flags&GRE_SEQ) - grehlen += 4; - } - if (len < grehlen + sizeof(struct iphdr)) - return; - eiph = (struct iphdr*)(dp + grehlen); - - switch (type) { - default: - return; - case ICMP_PARAMETERPROB: - n = ntohl(icmp_hdr(skb)->un.gateway) >> 24; - if (n < (iph->ihl<<2)) - return; - - /* So... This guy found something strange INSIDE encapsulated - packet. Well, he is fool, but what can we do ? - */ - rel_type = ICMP_PARAMETERPROB; - n -= grehlen; - rel_info = htonl(n << 24); - break; - - case ICMP_DEST_UNREACH: - switch (code) { - case ICMP_SR_FAILED: - case ICMP_PORT_UNREACH: - /* Impossible event. */ - return; - case ICMP_FRAG_NEEDED: - /* And it is the only really necessary thing :-) */ - n = ntohs(icmp_hdr(skb)->un.frag.mtu); - if (n < grehlen+68) - return; - n -= grehlen; - /* BSD 4.2 MORE DOES NOT EXIST IN NATURE. */ - if (n > ntohs(eiph->tot_len)) - return; - 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; - break; - } - - /* Prepare fake skb to feed it to icmp_send */ - skb2 = skb_clone(skb, GFP_ATOMIC); - if (skb2 == NULL) - return; - 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_dst = eiph->saddr; - fl.fl4_tos = RT_TOS(eiph->tos); - fl.proto = IPPROTO_GRE; - if (ip_route_output_key(dev_net(skb->dev), &rt, &fl)) { - kfree_skb(skb2); - return; - } - skb2->dev = rt->u.dst.dev; - - /* route "incoming" packet */ - if (rt->rt_flags&RTCF_LOCAL) { - ip_rt_put(rt); - rt = NULL; - fl.fl4_dst = 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_IPGRE) { - ip_rt_put(rt); - kfree_skb(skb2); - return; - } - } else { - ip_rt_put(rt); - if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, skb2->dev) || - skb2->dst->dev->type != ARPHRD_IPGRE) { - kfree_skb(skb2); - return; - } - } - - /* change mtu on this route */ - if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) { - if (n > dst_mtu(skb2->dst)) { - kfree_skb(skb2); - return; - } - 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); -#endif } static inline void ipgre_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb) |