alistair23-linux/net/ipv6/tcpv6_offload.c
Jerry Chu c3caf1192f net-gre-gro: Fix a bug that breaks the forwarding path
Fixed a bug that was introduced by my GRE-GRO patch
(bf5a755f5e net-gre-gro: Add GRE
support to the GRO stack) that breaks the forwarding path
because various GSO related fields were not set. The bug will
cause on the egress path either the GSO code to fail, or a
GRE-TSO capable (NETIF_F_GSO_GRE) NICs to choke. The following
fix has been tested for both cases.

Signed-off-by: H.K. Jerry Chu <hkchu@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-16 14:45:26 -07:00

94 lines
2.1 KiB
C

/*
* IPV6 GSO/GRO offload support
* Linux INET6 implementation
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* TCPv6 GSO/GRO support
*/
#include <linux/skbuff.h>
#include <net/protocol.h>
#include <net/tcp.h>
#include <net/ip6_checksum.h>
#include "ip6_offload.h"
static int tcp_v6_gso_send_check(struct sk_buff *skb)
{
const struct ipv6hdr *ipv6h;
struct tcphdr *th;
if (!pskb_may_pull(skb, sizeof(*th)))
return -EINVAL;
ipv6h = ipv6_hdr(skb);
th = tcp_hdr(skb);
th->check = 0;
skb->ip_summed = CHECKSUM_PARTIAL;
__tcp_v6_send_check(skb, &ipv6h->saddr, &ipv6h->daddr);
return 0;
}
static struct sk_buff **tcp6_gro_receive(struct sk_buff **head,
struct sk_buff *skb)
{
const struct ipv6hdr *iph = skb_gro_network_header(skb);
__wsum wsum;
/* Don't bother verifying checksum if we're going to flush anyway. */
if (NAPI_GRO_CB(skb)->flush)
goto skip_csum;
wsum = NAPI_GRO_CB(skb)->csum;
switch (skb->ip_summed) {
case CHECKSUM_NONE:
wsum = skb_checksum(skb, skb_gro_offset(skb), skb_gro_len(skb),
wsum);
/* fall through */
case CHECKSUM_COMPLETE:
if (!tcp_v6_check(skb_gro_len(skb), &iph->saddr, &iph->daddr,
wsum)) {
skb->ip_summed = CHECKSUM_UNNECESSARY;
break;
}
NAPI_GRO_CB(skb)->flush = 1;
return NULL;
}
skip_csum:
return tcp_gro_receive(head, skb);
}
static int tcp6_gro_complete(struct sk_buff *skb, int thoff)
{
const struct ipv6hdr *iph = ipv6_hdr(skb);
struct tcphdr *th = tcp_hdr(skb);
th->check = ~tcp_v6_check(skb->len - thoff, &iph->saddr,
&iph->daddr, 0);
skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV6;
return tcp_gro_complete(skb);
}
static const struct net_offload tcpv6_offload = {
.callbacks = {
.gso_send_check = tcp_v6_gso_send_check,
.gso_segment = tcp_gso_segment,
.gro_receive = tcp6_gro_receive,
.gro_complete = tcp6_gro_complete,
},
};
int __init tcpv6_offload_init(void)
{
return inet6_add_offload(&tcpv6_offload, IPPROTO_TCP);
}