4 files changed, 496 insertions, 0 deletions

diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index c5519250efd9..e0a979184c0a 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -135,6 +135,12 @@ config TUN
 
           If you don't know what to use this for, you don't need it.
 
+config VETH
+        tristate "Virtual ethernet device"
+        ---help---
+          The device is an ethernet tunnel. Devices are created in pairs. When
+          one end receives the packet it appears on its pair and vice versa.
+
 config NET_SB1000
         tristate "General Instruments Surfboard 1000"
         depends on PNP
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 9c928a845841..d6f7302ab72d 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -193,6 +193,7 @@ obj-$(CONFIG_MACSONIC) += macsonic.o
 obj-$(CONFIG_MACMACE) += macmace.o
 obj-$(CONFIG_MAC89x0) += mac89x0.o
 obj-$(CONFIG_TUN) += tun.o
+obj-$(CONFIG_VETH) += veth.o
 obj-$(CONFIG_NET_NETX) += netx-eth.o
 obj-$(CONFIG_DL2K) += dl2k.o
 obj-$(CONFIG_R8169) += r8169.o
diff --git a/drivers/net/veth.c b/drivers/net/veth.c
new file mode 100644
index 000000000000..ca1c6893b809
--- /dev/null
+++ b/drivers/net/veth.c
@@ -0,0 +1,477 @@
+/*
+ *  drivers/net/veth.c
+ *
+ *  Copyright (C) 2007 OpenVZ http://openvz.org, SWsoft Inc
+ *
+ * Author: Pavel Emelianov <xemul@openvz.org>
+ * Ethtool interface from: Eric W. Biederman <ebiederm@xmission.com>
+ *
+ */
+
+#include <linux/list.h>
+#include <linux/netdevice.h>
+#include <linux/ethtool.h>
+#include <linux/etherdevice.h>
+
+#include <net/dst.h>
+#include <net/xfrm.h>
+#include <net/veth.h>
+
+#define DRV_NAME        "veth"
+#define DRV_VERSION     "1.0"
+
+struct veth_net_stats {
+        unsigned long   rx_packets;
+        unsigned long   tx_packets;
+        unsigned long   rx_bytes;
+        unsigned long   tx_bytes;
+        unsigned long   tx_dropped;
+};
+
+struct veth_priv {
+        struct net_device *peer;
+        struct net_device *dev;
+        struct list_head list;
+        struct veth_net_stats *stats;
+        unsigned ip_summed;
+};
+
+static LIST_HEAD(veth_list);
+
+/*
+ * ethtool interface
+ */
+
+static struct {
+        const char string[ETH_GSTRING_LEN];
+} ethtool_stats_keys[] = {
+        { "peer_ifindex" },
+};
+
+static int veth_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
+{
+        cmd->supported          = 0;
+        cmd->advertising        = 0;
+        cmd->speed              = SPEED_10000;
+        cmd->duplex             = DUPLEX_FULL;
+        cmd->port               = PORT_TP;
+        cmd->phy_address        = 0;
+        cmd->transceiver        = XCVR_INTERNAL;
+        cmd->autoneg            = AUTONEG_DISABLE;
+        cmd->maxtxpkt           = 0;
+        cmd->maxrxpkt           = 0;
+        return 0;
+}
+
+static void veth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
+{
+        strcpy(info->driver, DRV_NAME);
+        strcpy(info->version, DRV_VERSION);
+        strcpy(info->fw_version, "N/A");
+}
+
+static void veth_get_strings(struct net_device *dev, u32 stringset, u8 *buf)
+{
+        switch(stringset) {
+        case ETH_SS_STATS:
+                memcpy(buf, &ethtool_stats_keys, sizeof(ethtool_stats_keys));
+                break;
+        }
+}
+
+static int veth_get_stats_count(struct net_device *dev)
+{
+        return ARRAY_SIZE(ethtool_stats_keys);
+}
+
+static void veth_get_ethtool_stats(struct net_device *dev,
+                struct ethtool_stats *stats, u64 *data)
+{
+        struct veth_priv *priv;
+
+        priv = netdev_priv(dev);
+        data[0] = priv->peer->ifindex;
+}
+
+static u32 veth_get_rx_csum(struct net_device *dev)
+{
+        struct veth_priv *priv;
+
+        priv = netdev_priv(dev);
+        return priv->ip_summed == CHECKSUM_UNNECESSARY;
+}
+
+static int veth_set_rx_csum(struct net_device *dev, u32 data)
+{
+        struct veth_priv *priv;
+
+        priv = netdev_priv(dev);
+        priv->ip_summed = data ? CHECKSUM_UNNECESSARY : CHECKSUM_NONE;
+        return 0;
+}
+
+static u32 veth_get_tx_csum(struct net_device *dev)
+{
+        return (dev->features & NETIF_F_NO_CSUM) != 0;
+}
+
+static int veth_set_tx_csum(struct net_device *dev, u32 data)
+{
+        if (data)
+                dev->features |= NETIF_F_NO_CSUM;
+        else
+                dev->features &= ~NETIF_F_NO_CSUM;
+        return 0;
+}
+
+static struct ethtool_ops veth_ethtool_ops = {
+        .get_settings           = veth_get_settings,
+        .get_drvinfo            = veth_get_drvinfo,
+        .get_link               = ethtool_op_get_link,
+        .get_rx_csum            = veth_get_rx_csum,
+        .set_rx_csum            = veth_set_rx_csum,
+        .get_tx_csum            = veth_get_tx_csum,
+        .set_tx_csum            = veth_set_tx_csum,
+        .get_sg                 = ethtool_op_get_sg,
+        .set_sg                 = ethtool_op_set_sg,
+        .get_strings            = veth_get_strings,
+        .get_stats_count        = veth_get_stats_count,
+        .get_ethtool_stats      = veth_get_ethtool_stats,
+};
+
+/*
+ * xmit
+ */
+
+static int veth_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+        struct net_device *rcv = NULL;
+        struct veth_priv *priv, *rcv_priv;
+        struct veth_net_stats *stats;
+        int length, cpu;
+
+        skb_orphan(skb);
+
+        priv = netdev_priv(dev);
+        rcv = priv->peer;
+        rcv_priv = netdev_priv(rcv);
+
+        cpu = smp_processor_id();
+        stats = per_cpu_ptr(priv->stats, cpu);
+
+        if (!(rcv->flags & IFF_UP))
+                goto outf;
+
+        skb->pkt_type = PACKET_HOST;
+        skb->protocol = eth_type_trans(skb, rcv);
+        if (dev->features & NETIF_F_NO_CSUM)
+                skb->ip_summed = rcv_priv->ip_summed;
+
+        dst_release(skb->dst);
+        skb->dst = NULL;
+        skb->mark = 0;
+        secpath_reset(skb);
+        nf_reset(skb);
+
+        length = skb->len;
+
+        stats->tx_bytes += length;
+        stats->tx_packets++;
+
+        stats = per_cpu_ptr(rcv_priv->stats, cpu);
+        stats->rx_bytes += length;
+        stats->rx_packets++;
+
+        netif_rx(skb);
+        return 0;
+
+outf:
+        kfree_skb(skb);
+        stats->tx_dropped++;
+        return 0;
+}
+
+/*
+ * general routines
+ */
+
+static struct net_device_stats *veth_get_stats(struct net_device *dev)
+{
+        struct veth_priv *priv;
+        struct net_device_stats *dev_stats;
+        int cpu;
+        struct veth_net_stats *stats;
+
+        priv = netdev_priv(dev);
+        dev_stats = &dev->stats;
+
+        dev_stats->rx_packets = 0;
+        dev_stats->tx_packets = 0;
+        dev_stats->rx_bytes = 0;
+        dev_stats->tx_bytes = 0;
+        dev_stats->tx_dropped = 0;
+
+        for_each_online_cpu(cpu) {
+                stats = per_cpu_ptr(priv->stats, cpu);
+
+                dev_stats->rx_packets += stats->rx_packets;
+                dev_stats->tx_packets += stats->tx_packets;
+                dev_stats->rx_bytes += stats->rx_bytes;
+                dev_stats->tx_bytes += stats->tx_bytes;
+                dev_stats->tx_dropped += stats->tx_dropped;
+        }
+
+        return dev_stats;
+}
+
+static int veth_open(struct net_device *dev)
+{
+        struct veth_priv *priv;
+
+        priv = netdev_priv(dev);
+        if (priv->peer == NULL)
+                return -ENOTCONN;
+
+        if (priv->peer->flags & IFF_UP) {
+                netif_carrier_on(dev);
+                netif_carrier_on(priv->peer);
+        }
+        return 0;
+}
+
+static int veth_close(struct net_device *dev)
+{
+        struct veth_priv *priv;
+
+        if (netif_carrier_ok(dev)) {
+                priv = netdev_priv(dev);
+                netif_carrier_off(dev);
+                netif_carrier_off(priv->peer);
+        }
+        return 0;
+}
+
+static int veth_dev_init(struct net_device *dev)
+{
+        struct veth_net_stats *stats;
+        struct veth_priv *priv;
+
+        stats = alloc_percpu(struct veth_net_stats);
+        if (stats == NULL)
+                return -ENOMEM;
+
+        priv = netdev_priv(dev);
+        priv->stats = stats;
+        return 0;
+}
+
+static void veth_dev_free(struct net_device *dev)
+{
+        struct veth_priv *priv;
+
+        priv = netdev_priv(dev);
+        free_percpu(priv->stats);
+        free_netdev(dev);
+}
+
+static void veth_setup(struct net_device *dev)
+{
+        ether_setup(dev);
+
+        dev->hard_start_xmit = veth_xmit;
+        dev->get_stats = veth_get_stats;
+        dev->open = veth_open;
+        dev->stop = veth_close;
+        dev->ethtool_ops = &veth_ethtool_ops;
+        dev->features |= NETIF_F_LLTX;
+        dev->init = veth_dev_init;
+        dev->destructor = veth_dev_free;
+}
+
+/*
+ * netlink interface
+ */
+
+static int veth_validate(struct nlattr *tb[], struct nlattr *data[])
+{
+        if (tb[IFLA_ADDRESS]) {
+                if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
+                        return -EINVAL;
+                if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
+                        return -EADDRNOTAVAIL;
+        }
+        return 0;
+}
+
+static struct rtnl_link_ops veth_link_ops;
+
+static int veth_newlink(struct net_device *dev,
+                         struct nlattr *tb[], struct nlattr *data[])
+{
+        int err;
+        struct net_device *peer;
+        struct veth_priv *priv;
+        char ifname[IFNAMSIZ];
+        struct nlattr *peer_tb[IFLA_MAX + 1], **tbp;
+
+        /*
+         * create and register peer first
+         *
+         * struct ifinfomsg is at the head of VETH_INFO_PEER, but we
+         * skip it since no info from it is useful yet
+         */
+
+        if (data != NULL && data[VETH_INFO_PEER] != NULL) {
+                struct nlattr *nla_peer;
+
+                nla_peer = data[VETH_INFO_PEER];
+                err = nla_parse(peer_tb, IFLA_MAX,
+                                nla_data(nla_peer) + sizeof(struct ifinfomsg),
+                                nla_len(nla_peer) - sizeof(struct ifinfomsg),
+                                ifla_policy);
+                if (err < 0)
+                        return err;
+
+                err = veth_validate(peer_tb, NULL);
+                if (err < 0)
+                        return err;
+
+                tbp = peer_tb;
+        } else
+                tbp = tb;
+
+        if (tbp[IFLA_IFNAME])
+                nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ);
+        else
+                snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");
+
+        peer = rtnl_create_link(ifname, &veth_link_ops, tbp);
+        if (IS_ERR(peer))
+                return PTR_ERR(peer);
+
+        if (tbp[IFLA_ADDRESS] == NULL)
+                random_ether_addr(peer->dev_addr);
+
+        err = register_netdevice(peer);
+        if (err < 0)
+                goto err_register_peer;
+
+        netif_carrier_off(peer);
+
+        /*
+         * register dev last
+         *
+         * note, that since we've registered new device the dev's name
+         * should be re-allocated
+         */
+
+        if (tb[IFLA_ADDRESS] == NULL)
+                random_ether_addr(dev->dev_addr);
+
+        if (tb[IFLA_IFNAME])
+                nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
+        else
+                snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");
+
+        if (strchr(dev->name, '%')) {
+                err = dev_alloc_name(dev, dev->name);
+                if (err < 0)
+                        goto err_alloc_name;
+        }
+
+        err = register_netdevice(dev);
+        if (err < 0)
+                goto err_register_dev;
+
+        netif_carrier_off(dev);
+
+        /*
+         * tie the deviced together
+         */
+
+        priv = netdev_priv(dev);
+        priv->dev = dev;
+        priv->peer = peer;
+        list_add(&priv->list, &veth_list);
+
+        priv = netdev_priv(peer);
+        priv->dev = peer;
+        priv->peer = dev;
+        INIT_LIST_HEAD(&priv->list);
+        return 0;
+
+err_register_dev:
+        /* nothing to do */
+err_alloc_name:
+        unregister_netdevice(peer);
+        return err;
+
+err_register_peer:
+        free_netdev(peer);
+        return err;
+}
+
+static void veth_dellink(struct net_device *dev)
+{
+        struct veth_priv *priv;
+        struct net_device *peer;
+
+        priv = netdev_priv(dev);
+        peer = priv->peer;
+
+        if (!list_empty(&priv->list))
+                list_del(&priv->list);
+
+        priv = netdev_priv(peer);
+        if (!list_empty(&priv->list))
+                list_del(&priv->list);
+
+        unregister_netdevice(dev);
+        unregister_netdevice(peer);
+}
+
+static const struct nla_policy veth_policy[VETH_INFO_MAX + 1];
+
+static struct rtnl_link_ops veth_link_ops = {
+        .kind           = DRV_NAME,
+        .priv_size      = sizeof(struct veth_priv),
+        .setup          = veth_setup,
+        .validate       = veth_validate,
+        .newlink        = veth_newlink,
+        .dellink        = veth_dellink,
+        .policy         = veth_policy,
+        .maxtype        = VETH_INFO_MAX,
+};
+
+/*
+ * init/fini
+ */
+
+static __init int veth_init(void)
+{
+        return rtnl_link_register(&veth_link_ops);
+}
+
+static __exit void veth_exit(void)
+{
+        struct veth_priv *priv, *next;
+
+        rtnl_lock();
+        /*
+         * cannot trust __rtnl_link_unregister() to unregister all
+         * devices, as each ->dellink call will remove two devices
+         * from the list at once.
+         */
+        list_for_each_entry_safe(priv, next, &veth_list, list)
+                veth_dellink(priv->dev);
+
+        __rtnl_link_unregister(&veth_link_ops);
+        rtnl_unlock();
+}
+
+module_init(veth_init);
+module_exit(veth_exit);
+
+MODULE_DESCRIPTION("Virtual Ethernet Tunnel");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS_RTNL_LINK(DRV_NAME);
diff --git a/include/net/veth.h b/include/net/veth.h
new file mode 100644
index 000000000000..3354c1eb424e
--- /dev/null
+++ b/include/net/veth.h
@@ -0,0 +1,12 @@
+#ifndef __NET_VETH_H_
+#define __NET_VETH_H_
+
+enum {
+        VETH_INFO_UNSPEC,
+        VETH_INFO_PEER,
+
+        __VETH_INFO_MAX
+#define VETH_INFO_MAX   (__VETH_INFO_MAX - 1)
+};
+
+#endif