IP_GRE: Fix IP-Identification.

GRE-GSO generates ip fragments with id 0,2,3,4... for every
GSO packet, which is not correct. Following patch fixes it
by setting ip-header id unique id of fragments are allowed.
As Eric Dumazet suggested it is optimized by using inner ip-header
whenever inner packet is ipv4.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Pravin B Shelar 2013-02-22 07:30:30 +00:00 committed by David S. Miller
parent 2bedc2e65b
commit 490ab08127
3 changed files with 23 additions and 3 deletions

View File

@ -71,4 +71,21 @@ static inline void iptunnel_xmit(struct sk_buff *skb, struct net_device *dev)
}
}
static inline void tunnel_ip_select_ident(struct sk_buff *skb,
const struct iphdr *old_iph,
struct dst_entry *dst)
{
struct iphdr *iph = ip_hdr(skb);
if (iph->frag_off & htons(IP_DF))
iph->id = 0;
else {
/* Use inner packet iph-id if possible. */
if (skb->protocol == htons(ETH_P_IP) && old_iph->id)
iph->id = old_iph->id;
else
__ip_select_ident(iph, dst,
(skb_shinfo(skb)->gso_segs ?: 1) - 1);
}
}
#endif

View File

@ -1332,8 +1332,10 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb,
if (skb->next != NULL)
iph->frag_off |= htons(IP_MF);
offset += (skb->len - skb->mac_len - iph->ihl * 4);
} else
} else {
if (!(iph->frag_off & htons(IP_DF)))
iph->id = htons(id++);
}
iph->tot_len = htons(skb->len - skb->mac_len);
iph->check = 0;
iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);

View File

@ -970,7 +970,8 @@ static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev
iph->daddr = fl4.daddr;
iph->saddr = fl4.saddr;
iph->ttl = ttl;
iph->id = 0;
tunnel_ip_select_ident(skb, old_iph, &rt->dst);
if (ttl == 0) {
if (skb->protocol == htons(ETH_P_IP))