ipv6: gso: make ipv6_gso_segment() stackable

In order to support GSO on SIT tunnels, we need to make
inet_gso_segment() stackable.

It should not assume network header starts right after mac
header.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2013-10-20 20:47:29 -07:00 committed by David S. Miller
parent 212124dd8a
commit d3e5e0062d

View File

@ -90,6 +90,7 @@ static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb,
u8 *prevhdr;
int offset = 0;
bool tunnel;
int nhoff;
if (unlikely(skb_shinfo(skb)->gso_type &
~(SKB_GSO_UDP |
@ -103,10 +104,16 @@ static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb,
0)))
goto out;
skb_reset_network_header(skb);
nhoff = skb_network_header(skb) - skb_mac_header(skb);
if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
goto out;
tunnel = skb->encapsulation;
tunnel = SKB_GSO_CB(skb)->encap_level > 0;
if (tunnel)
features = skb->dev->hw_enc_features & netif_skb_features(skb);
SKB_GSO_CB(skb)->encap_level += sizeof(*ipv6h);
ipv6h = ipv6_hdr(skb);
__skb_pull(skb, sizeof(*ipv6h));
segs = ERR_PTR(-EPROTONOSUPPORT);
@ -123,13 +130,17 @@ static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb,
goto out;
for (skb = segs; skb; skb = skb->next) {
ipv6h = ipv6_hdr(skb);
ipv6h->payload_len = htons(skb->len - skb->mac_len -
sizeof(*ipv6h));
ipv6h = (struct ipv6hdr *)(skb_mac_header(skb) + nhoff);
ipv6h->payload_len = htons(skb->len - nhoff - sizeof(*ipv6h));
if (tunnel) {
skb_reset_inner_headers(skb);
skb->encapsulation = 1;
}
skb->network_header = (u8 *)ipv6h - skb->head;
if (!tunnel && proto == IPPROTO_UDP) {
unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
fptr = (struct frag_hdr *)(skb_network_header(skb) +
unfrag_ip6hlen);
fptr = (struct frag_hdr *)((u8 *)ipv6h + unfrag_ip6hlen);
fptr->frag_off = htons(offset);
if (skb->next != NULL)
fptr->frag_off |= htons(IP6_MF);