ipv4: Save nexthop address of LSRR/SSRR option to IPCB.
We can not update iph->daddr in ip_options_rcv_srr(), It is too early.
When some exception ocurred later (eg. in ip_forward() when goto
sr_failed) we need the ip header be identical to the original one as
ICMP need it.
Add a field 'nexthop' in struct ip_options to save nexthop of LSRR
or SSRR option.
Signed-off-by: Li Wei <lw@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ip_forward.c b/net/ipv4/ip_forward.c
index 3b34d1c..29a07b6 100644
--- a/net/ipv4/ip_forward.c
+++ b/net/ipv4/ip_forward.c
@@ -84,7 +84,7 @@
rt = skb_rtable(skb);
- if (opt->is_strictroute && ip_hdr(skb)->daddr != rt->rt_gateway)
+ if (opt->is_strictroute && opt->nexthop != rt->rt_gateway)
goto sr_failed;
if (unlikely(skb->len > dst_mtu(&rt->dst) && !skb_is_gso(skb) &&
diff --git a/net/ipv4/ip_options.c b/net/ipv4/ip_options.c
index 05d20cc..1e60f76 100644
--- a/net/ipv4/ip_options.c
+++ b/net/ipv4/ip_options.c
@@ -568,12 +568,13 @@
) {
if (srrptr + 3 > srrspace)
break;
- if (memcmp(&ip_hdr(skb)->daddr, &optptr[srrptr-1], 4) == 0)
+ if (memcmp(&opt->nexthop, &optptr[srrptr-1], 4) == 0)
break;
}
if (srrptr + 3 <= srrspace) {
opt->is_changed = 1;
ip_rt_get_source(&optptr[srrptr-1], skb, rt);
+ ip_hdr(skb)->daddr = opt->nexthop;
optptr[2] = srrptr+4;
} else if (net_ratelimit())
printk(KERN_CRIT "ip_forward(): Argh! Destination lost!\n");
@@ -640,7 +641,7 @@
}
if (srrptr <= srrspace) {
opt->srr_is_hit = 1;
- iph->daddr = nexthop;
+ opt->nexthop = nexthop;
opt->is_changed = 1;
}
return 0;