* interface as the means of communication with the user level.
*
* The IP forwarding functionality.
- *
+ *
* Version: $Id: ip_forward.c,v 1.48 2000/12/13 18:31:48 davem Exp $
*
* Authors: see ip.c
*
* Fixes:
- * Many : Split from ip.c , see ip_input.c for
+ * Many : Split from ip.c , see ip_input.c for
* history.
- * Dave Gregorich : NULL ip_rt_put fix for multicast
+ * Dave Gregorich : NULL ip_rt_put fix for multicast
* routing.
* Jos Vos : Add call_out_firewall before sending,
* use output device for accounting.
#include <linux/types.h>
#include <linux/mm.h>
-#include <linux/sched.h>
#include <linux/skbuff.h>
#include <linux/ip.h>
#include <linux/icmp.h>
if (skb->pkt_type != PACKET_HOST)
goto drop;
- skb->ip_summed = CHECKSUM_NONE;
-
+ skb_forward_csum(skb);
+
/*
* According to the RFC, we must first decrease the TTL field. If
* that reaches zero, we must reply an ICMP control message telling
* that the packet's lifetime expired.
*/
- if (skb->nh.iph->ttl <= 1)
- goto too_many_hops;
+ if (ip_hdr(skb)->ttl <= 1)
+ goto too_many_hops;
if (!xfrm4_route_forward(skb))
goto drop;
if (opt->is_strictroute && rt->rt_dst != rt->rt_gateway)
goto sr_failed;
+ if (unlikely(skb->len > dst_mtu(&rt->u.dst) &&
+ (ip_hdr(skb)->frag_off & htons(IP_DF))) && !skb->local_df) {
+ IP_INC_STATS(IPSTATS_MIB_FRAGFAILS);
+ icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
+ htonl(dst_mtu(&rt->u.dst)));
+ goto drop;
+ }
+
/* We are about to mangle packet. Copy it! */
if (skb_cow(skb, LL_RESERVED_SPACE(rt->u.dst.dev)+rt->u.dst.header_len))
goto drop;
- iph = skb->nh.iph;
+ iph = ip_hdr(skb);
/* Decrease ttl after skb cow done */
ip_decrease_ttl(iph);
ip_forward_finish);
sr_failed:
- /*
+ /*
* Strict routing permits no gatewaying
*/
- icmp_send(skb, ICMP_DEST_UNREACH, ICMP_SR_FAILED, 0);
- goto drop;
+ icmp_send(skb, ICMP_DEST_UNREACH, ICMP_SR_FAILED, 0);
+ goto drop;
too_many_hops:
- /* Tell the sender its packet died... */
- IP_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS);
- icmp_send(skb, ICMP_TIME_EXCEEDED, ICMP_EXC_TTL, 0);
+ /* Tell the sender its packet died... */
+ IP_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS);
+ icmp_send(skb, ICMP_TIME_EXCEEDED, ICMP_EXC_TTL, 0);
drop:
kfree_skb(skb);
return NET_RX_DROP;