Commit e2521f0e authored by Zhang Chen's avatar Zhang Chen Committed by Jason Wang
Browse files

net/filter-mirror.c: Make filter mirror support vnet support. 



We add the vnet_hdr_support option for filter-mirror, default is disabled.
If you use virtio-net-pci or other driver needs vnet_hdr, please enable it.
You can use it for example:
-object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0,vnet_hdr_support

If it has vnet_hdr_support flag, we will change the sending packet format from
struct {int size; const uint8_t buf[];} to {int size; int vnet_hdr_len; const uint8_t buf[];}.
make other module(like colo-compare) know how to parse net packet correctly.

Signed-off-by: default avatarZhang Chen <zhangchen.fnst@cn.fujitsu.com>
Signed-off-by: default avatarJason Wang <jasowang@redhat.com>
parent dc3c5ac6

net/filter-mirror.c

+41 −1
Original line number Diff line number Diff line
@@ -41,12 +41,14 @@ typedef struct MirrorState { 
    CharBackend chr_in;

    CharBackend chr_out;

    SocketReadState rs;

    bool vnet_hdr;

} MirrorState;



static int filter_send(MirrorState *s,

                       const struct iovec *iov,

                       int iovcnt)

{

    NetFilterState *nf = NETFILTER(s);

    int ret = 0;

    ssize_t size = 0;

    uint32_t len = 0;
@@ -63,6 +65,23 @@ static int filter_send(MirrorState *s, 
        goto err;

    }



    if (s->vnet_hdr) {

        /*

         * If vnet_hdr = on, we send vnet header len to make other

         * module(like colo-compare) know how to parse net

         * packet correctly.

         */

        ssize_t vnet_hdr_len;



        vnet_hdr_len = nf->netdev->vnet_hdr_len;



        len = htonl(vnet_hdr_len);

        ret = qemu_chr_fe_write_all(&s->chr_out, (uint8_t *)&len, sizeof(len));

        if (ret != sizeof(len)) {

            goto err;

        }

    }



    buf = g_malloc(size);

    iov_to_buf(iov, iovcnt, 0, buf, size);

    ret = qemu_chr_fe_write_all(&s->chr_out, (uint8_t *)buf, size);
@@ -229,7 +248,7 @@ static void filter_redirector_setup(NetFilterState *nf, Error **errp) 
        }

    }



    net_socket_rs_init(&s->rs, redirector_rs_finalize, false);

    net_socket_rs_init(&s->rs, redirector_rs_finalize, s->vnet_hdr);



    if (s->indev) {

        chr = qemu_chr_find(s->indev);
@@ -318,6 +337,20 @@ static void filter_mirror_set_outdev(Object *obj, 
    }

}



static bool filter_mirror_get_vnet_hdr(Object *obj, Error **errp)

{

    MirrorState *s = FILTER_MIRROR(obj);



    return s->vnet_hdr;

}



static void filter_mirror_set_vnet_hdr(Object *obj, bool value, Error **errp)

{

    MirrorState *s = FILTER_MIRROR(obj);



    s->vnet_hdr = value;

}



static char *filter_redirector_get_outdev(Object *obj, Error **errp)

{

    MirrorState *s = FILTER_REDIRECTOR(obj);
@@ -337,8 +370,15 @@ static void filter_redirector_set_outdev(Object *obj, 


static void filter_mirror_init(Object *obj)

{

    MirrorState *s = FILTER_MIRROR(obj);



    object_property_add_str(obj, "outdev", filter_mirror_get_outdev,

                            filter_mirror_set_outdev, NULL);



    s->vnet_hdr = false;

    object_property_add_bool(obj, "vnet_hdr_support",

                             filter_mirror_get_vnet_hdr,

                             filter_mirror_set_vnet_hdr, NULL);

}



static void filter_redirector_init(Object *obj)

qemu-options.hx

+2 −3
Original line number Diff line number Diff line
@@ -4249,10 +4249,9 @@ queue @var{all|rx|tx} is an option that can be applied to any netfilter. 
@option{tx}: the filter is attached to the transmit queue of the netdev,

             where it will receive packets sent by the netdev.



@item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid}[,queue=@var{all|rx|tx}]

@item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]



filter-mirror on netdev @var{netdevid},mirror net packet to chardev

@var{chardevid}

filter-mirror on netdev @var{netdevid},mirror net packet to chardev@var{chardevid}, if it has the vnet_hdr_support flag, filter-mirror will mirror packet with vnet_hdr_len.



@item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},

outdev=@var{chardevid}[,queue=@var{all|rx|tx}]