+
+ /* It looks as overkill, because not all
+ IP options require packet mangling.
+ But it is the easiest for now, especially taking
+ into account that combination of IP options
+ and running sniffer is extremely rare condition.
+ --ANK (980813)
+ */
+ if (skb_cow(skb, skb_headroom(skb))) {
+ IP_INC_STATS_BH(IPSTATS_MIB_INDISCARDS);
+ goto drop;
+ }
+
+ iph = skb->nh.iph;
+
+ if (ip_options_compile(NULL, skb)) {
+ IP_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS);
+ goto drop;
+ }
+
+ opt = &(IPCB(skb)->opt);
+ if (unlikely(opt->srr)) {
+ struct in_device *in_dev = in_dev_get(dev);
+ if (in_dev) {
+ if (!IN_DEV_SOURCE_ROUTE(in_dev)) {
+ if (IN_DEV_LOG_MARTIANS(in_dev) &&
+ net_ratelimit())
+ printk(KERN_INFO "source route option "
+ "%u.%u.%u.%u -> %u.%u.%u.%u\n",
+ NIPQUAD(iph->saddr),
+ NIPQUAD(iph->daddr));
+ in_dev_put(in_dev);
+ goto drop;
+ }
+
+ in_dev_put(in_dev);
+ }
+
+ if (ip_options_rcv_srr(skb))
+ goto drop;
+ }
+
+ return 0;
+drop:
+ return -1;
+}
+
+static inline int ip_rcv_finish(struct sk_buff *skb)
+{