From 0b2e66448ba20eb30ea62345d6beb9ee2a1ce06b Mon Sep 17 00:00:00 2001 From: Gerard Garcia Date: Fri, 21 Apr 2017 10:10:45 +0100 Subject: [PATCH] VSOCK: Add vsockmon device 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 Signed-off-by: Stefan Hajnoczi Signed-off-by: David S. Miller --- MAINTAINERS | 2 + drivers/net/Kconfig | 8 ++ drivers/net/Makefile | 1 + drivers/net/vsockmon.c | 170 ++++++++++++++++++++++++++++++++++ include/uapi/linux/Kbuild | 1 + include/uapi/linux/vsockmon.h | 60 ++++++++++++ 6 files changed, 242 insertions(+) create mode 100644 drivers/net/vsockmon.c create mode 100644 include/uapi/linux/vsockmon.h diff --git a/MAINTAINERS b/MAINTAINERS index fdab4f9e8ac9..28ea78b12d0c 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -13317,9 +13317,11 @@ L: netdev@vger.kernel.org S: Maintained F: include/linux/virtio_vsock.h F: include/uapi/linux/virtio_vsock.h +F: include/uapi/linux/vsockmon.h F: net/vmw_vsock/af_vsock_tap.c F: net/vmw_vsock/virtio_transport_common.c F: net/vmw_vsock/virtio_transport.c +F: drivers/net/vsockmon.c F: drivers/vhost/vsock.c F: drivers/vhost/vsock.h diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig index 100fbdc9b95c..83a1616903f8 100644 --- a/drivers/net/Kconfig +++ b/drivers/net/Kconfig @@ -355,6 +355,14 @@ config NET_VRF This option enables the support for mapping interfaces into VRF's. The support enables VRF devices. +config VSOCKMON + tristate "Virtual vsock monitoring device" + depends on VHOST_VSOCK + ---help--- + This option enables a monitoring net device for vsock sockets. It is + mostly intended for developers or support to debug vsock issues. If + unsure, say N. + endif # NET_CORE config SUNGEM_PHY diff --git a/drivers/net/Makefile b/drivers/net/Makefile index 57fc47ad5ab3..b2f6556d8848 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/drivers/net/vsockmon.c b/drivers/net/vsockmon.c new file mode 100644 index 000000000000..7f0136f2dd9d --- /dev/null +++ b/drivers/net/vsockmon.c @@ -0,0 +1,170 @@ +#include +#include +#include +#include +#include +#include +#include +#include + +/* Virtio transport max packet size plus header */ +#define DEFAULT_MTU (VIRTIO_VSOCK_MAX_PKT_BUF_SIZE + \ + sizeof(struct af_vsockmon_hdr)) + +struct pcpu_lstats { + u64 rx_packets; + u64 rx_bytes; + struct u64_stats_sync syncp; +}; + +static int vsockmon_dev_init(struct net_device *dev) +{ + dev->lstats = netdev_alloc_pcpu_stats(struct pcpu_lstats); + if (!dev->lstats) + return -ENOMEM; + return 0; +} + +static void vsockmon_dev_uninit(struct net_device *dev) +{ + free_percpu(dev->lstats); +} + +struct vsockmon { + struct vsock_tap vt; +}; + +static int vsockmon_open(struct net_device *dev) +{ + struct vsockmon *vsockmon = netdev_priv(dev); + + vsockmon->vt.dev = dev; + vsockmon->vt.module = THIS_MODULE; + return vsock_add_tap(&vsockmon->vt); +} + +static int vsockmon_close(struct net_device *dev) +{ + struct vsockmon *vsockmon = netdev_priv(dev); + + return vsock_remove_tap(&vsockmon->vt); +} + +static netdev_tx_t vsockmon_xmit(struct sk_buff *skb, struct net_device *dev) +{ + int len = skb->len; + struct pcpu_lstats *stats = this_cpu_ptr(dev->lstats); + + u64_stats_update_begin(&stats->syncp); + stats->rx_bytes += len; + stats->rx_packets++; + u64_stats_update_end(&stats->syncp); + + dev_kfree_skb(skb); + + return NETDEV_TX_OK; +} + +static void +vsockmon_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats) +{ + int i; + u64 bytes = 0, packets = 0; + + for_each_possible_cpu(i) { + const struct pcpu_lstats *vstats; + u64 tbytes, tpackets; + unsigned int start; + + vstats = per_cpu_ptr(dev->lstats, i); + + do { + start = u64_stats_fetch_begin_irq(&vstats->syncp); + tbytes = vstats->rx_bytes; + tpackets = vstats->rx_packets; + } while (u64_stats_fetch_retry_irq(&vstats->syncp, start)); + + packets += tpackets; + bytes += tbytes; + } + + stats->rx_packets = packets; + stats->tx_packets = 0; + + stats->rx_bytes = bytes; + stats->tx_bytes = 0; +} + +static int vsockmon_is_valid_mtu(int new_mtu) +{ + return new_mtu >= (int)sizeof(struct af_vsockmon_hdr); +} + +static int vsockmon_change_mtu(struct net_device *dev, int new_mtu) +{ + if (!vsockmon_is_valid_mtu(new_mtu)) + return -EINVAL; + + dev->mtu = new_mtu; + return 0; +} + +static const struct net_device_ops vsockmon_ops = { + .ndo_init = vsockmon_dev_init, + .ndo_uninit = vsockmon_dev_uninit, + .ndo_open = vsockmon_open, + .ndo_stop = vsockmon_close, + .ndo_start_xmit = vsockmon_xmit, + .ndo_get_stats64 = vsockmon_get_stats64, + .ndo_change_mtu = vsockmon_change_mtu, +}; + +static u32 always_on(struct net_device *dev) +{ + return 1; +} + +static const struct ethtool_ops vsockmon_ethtool_ops = { + .get_link = always_on, +}; + +static void vsockmon_setup(struct net_device *dev) +{ + dev->type = ARPHRD_VSOCKMON; + dev->priv_flags |= IFF_NO_QUEUE; + + dev->netdev_ops = &vsockmon_ops; + dev->ethtool_ops = &vsockmon_ethtool_ops; + dev->destructor = free_netdev; + + dev->features = NETIF_F_SG | NETIF_F_FRAGLIST | + NETIF_F_HIGHDMA | NETIF_F_LLTX; + + dev->flags = IFF_NOARP; + + dev->mtu = DEFAULT_MTU; +} + +static struct rtnl_link_ops vsockmon_link_ops __read_mostly = { + .kind = "vsockmon", + .priv_size = sizeof(struct vsockmon), + .setup = vsockmon_setup, +}; + +static __init int vsockmon_register(void) +{ + return rtnl_link_register(&vsockmon_link_ops); +} + +static __exit void vsockmon_unregister(void) +{ + rtnl_link_unregister(&vsockmon_link_ops); +} + +module_init(vsockmon_register); +module_exit(vsockmon_unregister); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Gerard Garcia "); +MODULE_DESCRIPTION("Vsock monitoring device. Based on nlmon device."); +MODULE_ALIAS_RTNL_LINK("vsockmon"); diff --git a/include/uapi/linux/Kbuild b/include/uapi/linux/Kbuild index f8d9fed17ba9..6b0e2758585f 100644 --- a/include/uapi/linux/Kbuild +++ b/include/uapi/linux/Kbuild @@ -477,6 +477,7 @@ header-y += virtio_types.h header-y += virtio_vsock.h header-y += virtio_crypto.h header-y += vm_sockets.h +header-y += vsockmon.h header-y += vt.h header-y += vtpm_proxy.h header-y += wait.h diff --git a/include/uapi/linux/vsockmon.h b/include/uapi/linux/vsockmon.h new file mode 100644 index 000000000000..a08b522ef597 --- /dev/null +++ b/include/uapi/linux/vsockmon.h @@ -0,0 +1,60 @@ +#ifndef _UAPI_VSOCKMON_H +#define _UAPI_VSOCKMON_H + +#include + +/* + * 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 */ + __u8 reserved[2]; +}; + +enum af_vsockmon_op { + AF_VSOCK_OP_UNKNOWN = 0, + AF_VSOCK_OP_CONNECT = 1, + AF_VSOCK_OP_DISCONNECT = 2, + AF_VSOCK_OP_CONTROL = 3, + AF_VSOCK_OP_PAYLOAD = 4, +}; + +enum af_vsockmon_transport { + AF_VSOCK_TRANSPORT_UNKNOWN = 0, + AF_VSOCK_TRANSPORT_NO_INFO = 1, /* No transport information */ + + /* Transport header type: struct virtio_vsock_hdr */ + AF_VSOCK_TRANSPORT_VIRTIO = 2, +}; + +#endif