net/ipv4: Introduce IPSKB_FRAG_SEGS bit to inet_skb_parm.flags

This flag indicates whether fragmentation of segments is allowed.

Formerly this policy was hardcoded according to IPSKB_FORWARDED (set by
either ip_forward or ipmr_forward).

Cc: Hannes Frederic Sowa <[email protected]>
Cc: Florian Westphal <[email protected]>
Signed-off-by: Shmulik Ladkani <[email protected]>
Acked-by: Hannes Frederic Sowa <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
This commit is contained in:
Shmulik Ladkani 2016-07-18 14:49:33 +03:00 • committed by David S. Miller
commit 359ebda25a
4 changed files with 7 additions and 4 deletions

View file

@ -117,7 +117,7 @@ int ip_forward(struct sk_buff *skb)
if (opt->is_strictroute && rt->rt_uses_gateway)
goto sr_failed;
IPCB(skb)->flags |= IPSKB_FORWARDED;
IPCB(skb)->flags |= IPSKB_FORWARDED | IPSKB_FRAG_SEGS;
mtu = ip_dst_mtu_maybe_forward(&rt->dst, true);
if (ip_exceeds_mtu(skb, mtu)) {
IP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS);

View file

@ -223,8 +223,10 @@ static int ip_finish_output_gso(struct net *net, struct sock *sk,
struct sk_buff *segs;
int ret = 0;
/* common case: locally created skb or seglen is <= mtu */
if (((IPCB(skb)->flags & IPSKB_FORWARDED) == 0) ||
/* common case: fragmentation of segments is not allowed,
* or seglen is <= mtu
*/
if (((IPCB(skb)->flags & IPSKB_FRAG_SEGS) == 0) ||
skb_gso_validate_mtu(skb, mtu))
return ip_finish_output2(net, sk, skb);

View file

@ -1749,7 +1749,7 @@ static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt,
vif->dev->stats.tx_bytes += skb->len;
}
IPCB(skb)->flags |= IPSKB_FORWARDED;
IPCB(skb)->flags |= IPSKB_FORWARDED | IPSKB_FRAG_SEGS;
/* RFC1584 teaches, that DVMRP/PIM router must deliver packets locally
* not only before forwarding, but after forwarding on all output