On Wed, Apr 12, 2017 at 05:08:24PM +0100, Stefan Hajnoczi wrote:
> From: Gerard Garcia <ggar...@deic.uab.cat>
>
> Add vsockmon virtual network device that receives packets from the vsock
> transports and exposes them to user space.
>
> Based on the nlmon device.
>
> Signed-off-by: Gerard Garcia <ggar...@deic.uab.cat>
> Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
> ---
> v3:
> * Fix DEFAULT_MTU macro definition [Zhu Yanjun]
> * Rename af_vsockmon_hdr->t field ->transport for clarity
> * Update .ndo_get_stats64() return type since it has changed
> ---
> drivers/net/Makefile | 1 +
> include/uapi/linux/vsockmon.h | 57 ++++++++++++++
> drivers/net/vsockmon.c | 167
> ++++++++++++++++++++++++++++++++++++++++++
> drivers/net/Kconfig | 8 ++
> include/uapi/linux/Kbuild | 1 +
> 5 files changed, 234 insertions(+)
> create mode 100644 include/uapi/linux/vsockmon.h
> create mode 100644 drivers/net/vsockmon.c
>
> diff --git a/drivers/net/Makefile b/drivers/net/Makefile
> index 98ed4d9..2d54930 100644
> --- a/drivers/net/Makefile
> +++ b/drivers/net/Makefile
> @@ -30,6 +30,7 @@ obj-$(CONFIG_GENEVE) += geneve.o
> obj-$(CONFIG_GTP) += gtp.o
> obj-$(CONFIG_NLMON) += nlmon.o
> obj-$(CONFIG_NET_VRF) += vrf.o
> +obj-$(CONFIG_VSOCKMON) += vsockmon.o
>
> #
> # Networking Drivers
> diff --git a/include/uapi/linux/vsockmon.h b/include/uapi/linux/vsockmon.h
> new file mode 100644
> index 0000000..484e59e
> --- /dev/null
> +++ b/include/uapi/linux/vsockmon.h
> @@ -0,0 +1,57 @@
> +#ifndef _UAPI_VSOCKMON_H
> +#define _UAPI_VSOCKMON_H
> +
> +#include <linux/virtio_vsock.h>
> +
> +/*
> + * vsockmon is the AF_VSOCK packet capture device. Packets captured have the
> + * following layout:
> + *
> + * +-----------------------------------+
> + * | vsockmon header |
> + * | (struct af_vsockmon_hdr) |
> + * +-----------------------------------+
> + * | transport header |
> + * | (af_vsockmon_hdr->len bytes long) |
> + * +-----------------------------------+
> + * | payload |
> + * | (until end of packet) |
> + * +-----------------------------------+
> + *
> + * The vsockmon header is a transport-independent description of the packet.
> + * It duplicates some of the information from the transport header so that
> + * no transport-specific knowledge is necessary to process packets.
> + *
> + * The transport header is useful for low-level transport-specific packet
> + * analysis. Transport type is given in af_vsockmon_hdr->transport and
> + * transport header length is given in af_vsockmon_hdr->len.
> + *
> + * If af_vsockmon_hdr->op is AF_VSOCK_OP_PAYLOAD then the payload follows the
> + * transport header. Other ops do not have a payload.
> + */
> +
> +struct af_vsockmon_hdr {
> + __le64 src_cid;
> + __le64 dst_cid;
> + __le32 src_port;
> + __le32 dst_port;
> + __le16 op; /* enum af_vsockmon_op */
> + __le16 transport; /* enum af_vsockmon_transport */
> + __le16 len; /* Transport header length */
> +} __attribute__((packed));
I'd add a 2 byte padding here and then you do not need to pack it.
