Re: [Qemu-devel] [PATCH V4 10/12] net/colo-compare.c: Add vnet packet's tcp/udp/icmp compare

[Jason Wang <jasowang@redhat.com>]

On 2017年05月12日 09:41, Zhang Chen wrote:
> COLO-Proxy just focus on packet payload, So we skip vnet header.
>
> Signed-off-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
> ---
>   net/colo-compare.c | 12 +++++++++---
>   1 file changed, 9 insertions(+), 3 deletions(-)
>
> diff --git a/net/colo-compare.c b/net/colo-compare.c
> index cb0b04e..bf565f3 100644
> --- a/net/colo-compare.c
> +++ b/net/colo-compare.c
> @@ -188,6 +188,8 @@ static int packet_enqueue(CompareState *s, int mode)
>    */
>   static int colo_packet_compare_common(Packet *ppkt, Packet *spkt, int offset)
>   {
> +    int offset_all;
> +
>       if (trace_event_get_state(TRACE_COLO_COMPARE_MISCOMPARE)) {
>           char pri_ip_src[20], pri_ip_dst[20], sec_ip_src[20], sec_ip_dst[20];
>   
> @@ -201,9 +203,12 @@ static int colo_packet_compare_common(Packet *ppkt, Packet *spkt, int offset)
>                                      sec_ip_src, sec_ip_dst);
>       }
>   
> +    offset_all = ppkt->vnet_hdr_len + offset;

How about just keep using offset by increasing it with vnet_hdr_len?

Thanks

> +
>       if (ppkt->size == spkt->size) {
> -        return memcmp(ppkt->data + offset, spkt->data + offset,
> -                      spkt->size - offset);
> +        return memcmp(ppkt->data + offset_all,
> +                      spkt->data + offset_all,
> +                      spkt->size - offset_all);
>       } else {
>           trace_colo_compare_main("Net packet size are not the same");
>           return -1;
> @@ -261,8 +266,9 @@ static int colo_packet_compare_tcp(Packet *spkt, Packet *ppkt)
>        */
>       if (ptcp->th_off > 5) {
>           ptrdiff_t tcp_offset;
> +
>           tcp_offset = ppkt->transport_header - (uint8_t *)ppkt->data
> -                     + (ptcp->th_off * 4);
> +                     + (ptcp->th_off * 4) - ppkt->vnet_hdr_len;
>           res = colo_packet_compare_common(ppkt, spkt, tcp_offset);
>       } else if (ptcp->th_sum == stcp->th_sum) {
>           res = colo_packet_compare_common(ppkt, spkt, ETH_HLEN);