X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;ds=sidebyside;f=lib%2Fnetdev-linux.c;h=18d327425a8afd46f6e12552f41c5f3cb40828e4;hb=36775dad3505929f8370166c33e8e0f04ca96c1c;hp=11d83e9716e559701de5e477a9259d1fbe9b7571;hpb=8398cf7efc3979cd6c8152915a584c13873ee322;p=openvswitch

diff --git a/lib/netdev-linux.c b/lib/netdev-linux.c
index 11d83e97..18d32742 100644
--- a/lib/netdev-linux.c
+++ b/lib/netdev-linux.c
@@ -21,6 +21,7 @@
 #include <arpa/inet.h>
 #include <inttypes.h>
 #include <linux/if_tun.h>
+#include <linux/ip.h>
 #include <linux/types.h>
 #include <linux/ethtool.h>
 #include <linux/rtnetlink.h>
@@ -32,6 +33,7 @@
 #include <netpacket/packet.h>
 #include <net/ethernet.h>
 #include <net/if.h>
+#include <linux/if_tunnel.h>
 #include <net/if_arp.h>
 #include <net/if_packet.h>
 #include <net/route.h>
@@ -48,6 +50,7 @@
 #include "netlink.h"
 #include "ofpbuf.h"
 #include "openflow/openflow.h"
+#include "openvswitch/gre.h"
 #include "packets.h"
 #include "poll-loop.h"
 #include "rtnetlink.h"
@@ -55,6 +58,10 @@
 #include "shash.h"
 #include "svec.h"
 
+#ifndef GRE_IOCTL_ONLY
+#include <linux/if_link.h>
+#endif
+
 #define THIS_MODULE VLM_netdev_linux
 #include "vlog.h"
 
@@ -67,6 +74,19 @@
 #define ADVERTISED_Asym_Pause           (1 << 14)
 #endif
 
+struct tap_state {
+    int tap_fd;                 /* File descriptor for TAP device. */
+};
+
+/* Provider-specific netdev object.  Netdev objects are devices that are
+ * created by the netdev library through a netdev_create() call. */
+struct netdev_obj_linux {
+    struct netdev_obj netdev_obj;
+    union {
+        struct tap_state tap;
+    } state;
+};
+
 struct netdev_linux {
     struct netdev netdev;
 
@@ -85,7 +105,8 @@ enum {
     VALID_IN4 = 1 << 2,
     VALID_IN6 = 1 << 3,
     VALID_MTU = 1 << 4,
-    VALID_CARRIER = 1 << 5
+    VALID_CARRIER = 1 << 5,
+    VALID_IS_INTERNAL = 1 << 6
 };
 
 /* Cached network device information. */
@@ -100,6 +121,7 @@ struct netdev_linux_cache {
     struct in6_addr in6;
     int mtu;
     int carrier;
+    bool is_internal;
 };
 
 static struct shash cache_map = SHASH_INITIALIZER(&cache_map);
@@ -108,6 +130,25 @@ static struct rtnetlink_notifier netdev_linux_cache_notifier;
 /* An AF_INET socket (used for ioctl operations). */
 static int af_inet_sock = -1;
 
+struct gre_config {
+    uint32_t local_ip;
+    uint32_t remote_ip;
+    uint32_t in_key;
+    uint32_t out_key;
+    bool have_in_key;
+    bool have_out_key;
+    bool in_csum;
+    bool out_csum;
+};
+
+static struct {
+    union {
+        struct nl_sock *nl_sock;
+        int ioctl_fd;
+    };
+    bool use_ioctl;
+} gre_descriptors;
+
 struct netdev_linux_notifier {
     struct netdev_notifier notifier;
     struct list node;
@@ -140,6 +181,16 @@ static int set_etheraddr(const char *netdev_name, int hwaddr_family,
 static int get_stats_via_netlink(int ifindex, struct netdev_stats *stats);
 static int get_stats_via_proc(const char *netdev_name, struct netdev_stats *stats);
 
+static struct netdev_obj_linux *
+netdev_obj_linux_cast(const struct netdev_obj *netdev_obj)
+{
+    /* xxx Gross hack!  Until we get the class 'type' issue resolved. */
+#if 0
+    netdev_obj_assert_class(netdev_obj, &netdev_linux_class);
+#endif
+    return CONTAINER_OF(netdev_obj, struct netdev_obj_linux, netdev_obj);
+}
+
 static struct netdev_linux *
 netdev_linux_cast(const struct netdev *netdev)
 {
@@ -192,20 +243,454 @@ netdev_linux_cache_cb(const struct rtnetlink_change *change,
     }
 }
 
+/* The arguments are marked as unused to prevent warnings on platforms where
+ * the Netlink interface isn't supported. */
+static int
+setup_gre_netlink(const char *name UNUSED, struct gre_config *config UNUSED,
+                  bool create UNUSED)
+{
+#ifdef GRE_IOCTL_ONLY
+    return EOPNOTSUPP;
+#else
+    int error;
+    struct ofpbuf request, *reply;
+    unsigned int nl_flags;
+    struct ifinfomsg ifinfomsg;
+    struct nlattr *linkinfo_hdr;
+    struct nlattr *info_data_hdr;
+    uint16_t iflags = 0;
+    uint16_t oflags = 0;
+    uint8_t pmtudisc = 0;
+
+    if (!gre_descriptors.nl_sock) {
+        error = nl_sock_create(NETLINK_ROUTE, 0, 0, 0,
+                               &gre_descriptors.nl_sock);
+        if (error) {
+            VLOG_WARN("couldn't create netlink socket: %s\n", strerror(error));
+            gre_descriptors.nl_sock = NULL;
+            goto error;
+        }
+    }
+
+    ofpbuf_init(&request, 0);
+
+    nl_flags = NLM_F_REQUEST;
+    if (create) {
+        nl_flags |= NLM_F_CREATE|NLM_F_EXCL;
+    }
+
+    /* We over-reserve space, because we do some pointer arithmetic
+     * and don't want the buffer address shifting under us. */
+    nl_msg_put_nlmsghdr(&request, gre_descriptors.nl_sock, 2048, RTM_NEWLINK,
+                        nl_flags);
+
+    memset(&ifinfomsg, 0, sizeof ifinfomsg);
+    ifinfomsg.ifi_family = AF_UNSPEC;
+    nl_msg_put(&request, &ifinfomsg, sizeof ifinfomsg);
+
+    linkinfo_hdr = ofpbuf_tail(&request);
+    nl_msg_put_unspec(&request, IFLA_LINKINFO, NULL, 0);
+
+    nl_msg_put_unspec(&request, IFLA_INFO_KIND, "gretap", 6);
+
+    info_data_hdr = ofpbuf_tail(&request);
+    nl_msg_put_unspec(&request, IFLA_INFO_DATA, NULL, 0);
+
+    /* Set flags */
+    if (config->have_in_key) {
+        iflags |= GRE_KEY;
+    }
+    if (config->have_out_key) {
+        oflags |= GRE_KEY;
+    }
+
+    if (config->in_csum) {
+        iflags |= GRE_CSUM;
+    }
+    if (config->out_csum) {
+        oflags |= GRE_CSUM;
+    }
+
+    /* Add options */
+    nl_msg_put_u32(&request, IFLA_GRE_IKEY, config->in_key);
+    nl_msg_put_u32(&request, IFLA_GRE_OKEY, config->out_key);
+    nl_msg_put_u16(&request, IFLA_GRE_IFLAGS, iflags);
+    nl_msg_put_u16(&request, IFLA_GRE_OFLAGS, oflags);
+    nl_msg_put_u32(&request, IFLA_GRE_LOCAL, config->local_ip);
+    nl_msg_put_u32(&request, IFLA_GRE_REMOTE, config->remote_ip);
+    nl_msg_put_u8(&request, IFLA_GRE_PMTUDISC, pmtudisc);
+    nl_msg_put_u8(&request, IFLA_GRE_TTL, 0);
+    nl_msg_put_u8(&request, IFLA_GRE_TOS, 0);
+
+    info_data_hdr->nla_len = (char *)ofpbuf_tail(&request)
+                                - (char *)info_data_hdr;
+    linkinfo_hdr->nla_len = (char *)ofpbuf_tail(&request)
+                                - (char *)linkinfo_hdr;
+
+    nl_msg_put_string(&request, IFLA_IFNAME, name);
+
+    error = nl_sock_transact(gre_descriptors.nl_sock, &request, &reply);
+    ofpbuf_uninit(&request);
+    if (error) {
+        VLOG_WARN("couldn't transact netlink socket: %s\n", strerror(error));
+        goto error;
+    }
+    ofpbuf_delete(reply);
+
+error:
+    return error;
+#endif
+}
+
+static int
+setup_gre_ioctl(const char *name, struct gre_config *config, bool create)
+{
+    struct ip_tunnel_parm p;
+    struct ifreq ifr;
+
+    memset(&p, 0, sizeof p);
+
+    strncpy(p.name, name, IFNAMSIZ);
+
+    p.iph.version = 4;
+    p.iph.ihl = 5;
+    p.iph.protocol = IPPROTO_GRE;
+    p.iph.saddr = config->local_ip;
+    p.iph.daddr = config->remote_ip;
+
+    if (config->have_in_key) {
+        p.i_flags |= GRE_KEY;
+        p.i_key = config->in_key;
+    }
+    if (config->have_out_key) {
+        p.o_flags |= GRE_KEY;
+        p.o_key = config->out_key;
+    }
+
+    if (config->in_csum) {
+        p.i_flags |= GRE_CSUM;
+    }
+    if (config->out_csum) {
+        p.o_flags |= GRE_CSUM;
+    }
+
+    strncpy(ifr.ifr_name, create ? GRE_IOCTL_DEVICE : name, IFNAMSIZ);
+    ifr.ifr_ifru.ifru_data = (void *)&p;
+
+    if (!gre_descriptors.ioctl_fd) {
+        gre_descriptors.ioctl_fd = socket(AF_INET, SOCK_DGRAM, 0);
+        if (gre_descriptors.ioctl_fd < 0) {
+            VLOG_WARN("couldn't create gre ioctl socket: %s\n", strerror(errno));
+            gre_descriptors.ioctl_fd = 0;
+            return errno;
+        }
+    }
+
+    if (ioctl(gre_descriptors.ioctl_fd, create ? SIOCADDGRETAP : SIOCCHGGRETAP,
+              &ifr) < 0) {
+        VLOG_WARN("couldn't do gre ioctl: %s\n", strerror(errno));
+        return errno;
+    }
+
+    return 0;
+}
+
+static int
+setup_gre(const char *name, const struct shash *args, bool create)
+{
+    int error;
+    struct in_addr in_addr;
+    struct shash_node *node;
+    struct gre_config config;
+
+    memset(&config, 0, sizeof config);
+    config.in_csum = true;
+    config.out_csum = true;
+
+    SHASH_FOR_EACH (node, args) {
+        if (!strcmp(node->name, "remote_ip")) {
+            if (lookup_ip(node->data, &in_addr)) {
+                VLOG_WARN("bad 'remote_ip' for gre device %s ", name);
+            } else {
+                config.remote_ip = in_addr.s_addr;
+            }
+        } else if (!strcmp(node->name, "local_ip")) {
+            if (lookup_ip(node->data, &in_addr)) {
+                VLOG_WARN("bad 'local_ip' for gre device %s ", name);
+            } else {
+                config.local_ip = in_addr.s_addr;
+            }
+        } else if (!strcmp(node->name, "key")) {
+            config.have_in_key = true;
+            config.have_out_key = true;
+            config.in_key = htonl(atoi(node->data));
+            config.out_key = htonl(atoi(node->data));
+        } else if (!strcmp(node->name, "in_key")) {
+            config.have_in_key = true;
+            config.in_key = htonl(atoi(node->data));
+        } else if (!strcmp(node->name, "out_key")) {
+            config.have_out_key = true;
+            config.out_key = htonl(atoi(node->data));
+        } else if (!strcmp(node->name, "csum")) {
+            if (!strcmp(node->data, "false")) {
+                config.in_csum = false;
+                config.out_csum = false;
+            }
+        } else {
+            VLOG_WARN("unknown gre argument '%s'", node->name);
+        }
+    }
+
+    if (!config.remote_ip) {
+        VLOG_WARN("gre type requires valid 'remote_ip' argument");
+        error = EINVAL;
+        goto error;
+    }
+
+    if (!gre_descriptors.use_ioctl) {
+        error = setup_gre_netlink(name, &config, create);
+        if (error == EOPNOTSUPP) {
+            gre_descriptors.use_ioctl = true;
+        }
+    }
+    if (gre_descriptors.use_ioctl) {
+        error = setup_gre_ioctl(name, &config, create);
+    }
+
+error:
+    return error;
+}
+
+static int
+if_up(const char *name)
+{
+    struct ifreq ifr;
+
+    strncpy(ifr.ifr_name, name, sizeof ifr.ifr_name);
+    ifr.ifr_flags = IFF_UP;
+
+    if (ioctl(af_inet_sock, SIOCSIFFLAGS, &ifr) == -1) {
+        VLOG_DBG_RL(&rl, "%s: failed to bring device up: %s",
+                    name, strerror(errno));
+        return errno;
+    }
+
+    return 0;
+}
+
+/* Creates the netdev object of 'type' with 'name'. */
+static int
+netdev_linux_create_system(const char *name, const char *type UNUSED,
+                    const struct shash *args, bool created)
+{
+    struct netdev_obj_linux *netdev_obj;
+
+    if (!shash_is_empty(args)) {
+        VLOG_WARN("arguments for system devices should be empty");
+    }
+
+    netdev_obj = xcalloc(1, sizeof *netdev_obj);
+    netdev_obj_init(&netdev_obj->netdev_obj, name, &netdev_linux_class,
+                    created);
+
+    return 0;
+}
+
+static int
+netdev_linux_create_tap(const char *name, const char *type UNUSED,
+                    const struct shash *args, bool created)
+{
+    struct netdev_obj_linux *netdev_obj;
+    struct tap_state *state;
+    static const char tap_dev[] = "/dev/net/tun";
+    struct ifreq ifr;
+    int error;
+
+    if (!shash_is_empty(args)) {
+        VLOG_WARN("arguments for TAP devices should be empty");
+    }
+
+    netdev_obj = xcalloc(1, sizeof *netdev_obj);
+    netdev_obj_init(&netdev_obj->netdev_obj, name, &netdev_tap_class, created);
+
+    state = &netdev_obj->state.tap;
+
+    /* Open tap device. */
+    state->tap_fd = open(tap_dev, O_RDWR);
+    if (state->tap_fd < 0) {
+        error = errno;
+        VLOG_WARN("opening \"%s\" failed: %s", tap_dev, strerror(error));
+        goto error;
+    }
+
+    /* Create tap device. */
+    ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
+    strncpy(ifr.ifr_name, name, sizeof ifr.ifr_name);
+    if (ioctl(state->tap_fd, TUNSETIFF, &ifr) == -1) {
+        VLOG_WARN("%s: creating tap device failed: %s", name,
+                  strerror(errno));
+        error = errno;
+        goto error;
+    }
+
+    /* Make non-blocking. */
+    error = set_nonblocking(state->tap_fd);
+    if (error) {
+        goto error;
+    }
+
+    error = if_up(name);
+    if (error) {
+        goto error;
+    }
+
+    return 0;
+
+error:
+    netdev_destroy(name);
+    return error;
+}
+
+static int
+netdev_linux_create_gre(const char *name, const char *type UNUSED,
+                    const struct shash *args, bool created)
+{
+    struct netdev_obj_linux *netdev_obj;
+    int error;
+
+    netdev_obj = xcalloc(1, sizeof *netdev_obj);
+    netdev_obj_init(&netdev_obj->netdev_obj, name, &netdev_gre_class, created);
+
+    error = setup_gre(name, args, true);
+    if (error) {
+        goto error;
+    }
+
+    error = if_up(name);
+    if (error) {
+        goto error;
+    }
+
+    return 0;
+
+error:
+    netdev_destroy(name);
+    return error;
+}
+
+static int
+netdev_linux_reconfigure_gre(struct netdev_obj *netdev_obj_,
+                             const struct shash *args)
+{
+    struct netdev_obj_linux *netdev_obj = netdev_obj_linux_cast(netdev_obj_);
+    const char *name = netdev_obj_get_name(&netdev_obj->netdev_obj);
+
+    return setup_gre(name, args, false);
+}
+
+/* The arguments are marked as unused to prevent warnings on platforms where
+ * the Netlink interface isn't supported. */
+static int
+destroy_gre_netlink(struct netdev_obj_linux *netdev_obj UNUSED)
+{
+#ifdef GRE_IOCTL_ONLY
+    return EOPNOTSUPP;
+#else
+    const char *name = netdev_obj_get_name(&netdev_obj->netdev_obj);
+    int error;
+    struct ofpbuf request, *reply;
+    struct ifinfomsg ifinfomsg;
+    int ifindex;
+
+    ofpbuf_init(&request, 0);
+    
+    nl_msg_put_nlmsghdr(&request, gre_descriptors.nl_sock, 0, RTM_DELLINK,
+                        NLM_F_REQUEST);
+
+    memset(&ifinfomsg, 0, sizeof ifinfomsg);
+    ifinfomsg.ifi_family = AF_UNSPEC;
+    nl_msg_put(&request, &ifinfomsg, sizeof ifinfomsg);
+
+    ifindex = do_get_ifindex(name);
+    nl_msg_put_u32(&request, IFLA_LINK, ifindex);
+
+    nl_msg_put_string(&request, IFLA_IFNAME, name);
+
+    error = nl_sock_transact(gre_descriptors.nl_sock, &request, &reply);
+    ofpbuf_uninit(&request);
+    if (error) {
+        VLOG_WARN("couldn't transact netlink socket: %s\n", strerror(error));
+        goto error;
+    }
+    ofpbuf_delete(reply);
+
+error:
+    return 0;
+#endif
+}
+
+static int
+destroy_gre_ioctl(struct netdev_obj_linux *netdev_obj)
+{
+    const char *name = netdev_obj_get_name(&netdev_obj->netdev_obj);
+    struct ip_tunnel_parm p;
+    struct ifreq ifr;
+
+    memset(&p, 0, sizeof p);
+    strncpy(p.name, name, IFNAMSIZ);
+
+    strncpy(ifr.ifr_name, name, IFNAMSIZ);
+    ifr.ifr_ifru.ifru_data = (void *)&p;
+
+    if (ioctl(gre_descriptors.ioctl_fd, SIOCDELGRETAP, &ifr) < 0) {
+        VLOG_WARN("couldn't do gre ioctl: %s\n", strerror(errno));
+        return errno;
+    }
+
+    return 0;
+}
+
+static void
+destroy_tap(struct netdev_obj_linux *netdev_obj)
+{
+    struct tap_state *state = &netdev_obj->state.tap;
+    if (state->tap_fd >= 0) {
+        close(state->tap_fd);
+    }
+}
+
+/* Destroys the netdev object 'netdev_obj_'. */
+static void
+netdev_linux_destroy(struct netdev_obj *netdev_obj_)
+{
+    struct netdev_obj_linux *netdev_obj = netdev_obj_linux_cast(netdev_obj_);
+    const char *type = netdev_obj_get_type(netdev_obj_);
+
+    if (!strcmp(type, "tap")) {
+        destroy_tap(netdev_obj);
+    } else if (!strcmp(type, "gre")) {
+        if (gre_descriptors.use_ioctl) {
+            destroy_gre_ioctl(netdev_obj);
+        } else {
+            destroy_gre_netlink(netdev_obj);
+        }
+    }
+    free(netdev_obj);
+}
+
 static int
-netdev_linux_open(const char *name, char *suffix, int ethertype,
-                  struct netdev **netdevp)
+netdev_linux_open(const char *name, int ethertype, struct netdev **netdevp)
 {
     struct netdev_linux *netdev;
     enum netdev_flags flags;
     int error;
 
     /* Allocate network device. */
-    netdev = xcalloc(1, sizeof *netdev);
-    netdev_init(&netdev->netdev, suffix, &netdev_linux_class);
+    netdev = xzalloc(sizeof *netdev);
+    netdev_init(&netdev->netdev, name, &netdev_linux_class);
     netdev->netdev_fd = -1;
     netdev->tap_fd = -1;
-    netdev->cache = shash_find_data(&cache_map, suffix);
+    netdev->cache = shash_find_data(&cache_map, name);
     if (!netdev->cache) {
         if (shash_is_empty(&cache_map)) {
             int error = rtnetlink_notifier_register(
@@ -216,14 +701,14 @@ netdev_linux_open(const char *name, char *suffix, int ethertype,
             }
         }
         netdev->cache = xmalloc(sizeof *netdev->cache);
-        netdev->cache->shash_node = shash_add(&cache_map, suffix,
+        netdev->cache->shash_node = shash_add(&cache_map, name,
                                               netdev->cache);
         netdev->cache->valid = 0;
         netdev->cache->ref_cnt = 0;
     }
     netdev->cache->ref_cnt++;
 
-    if (!strncmp(name, "tap:", 4)) {
+    if (!strcmp(netdev_get_type(&netdev->netdev), "tap")) {
         static const char tap_dev[] = "/dev/net/tun";
         struct ifreq ifr;
 
@@ -237,9 +722,11 @@ netdev_linux_open(const char *name, char *suffix, int ethertype,
 
         /* Create tap device. */
         ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
-        error = netdev_linux_do_ioctl(&netdev->netdev, &ifr,
-                                      TUNSETIFF, "TUNSETIFF");
-        if (error) {
+        strncpy(ifr.ifr_name, name, sizeof ifr.ifr_name);
+        if (ioctl(netdev->tap_fd, TUNSETIFF, &ifr) == -1) {
+            VLOG_WARN("%s: creating tap device failed: %s", name,
+                      strerror(errno));
+            error = errno;
             goto error;
         }
 
@@ -292,7 +779,7 @@ netdev_linux_open(const char *name, char *suffix, int ethertype,
         if (bind(netdev->netdev_fd,
                  (struct sockaddr *) &sll, sizeof sll) < 0) {
             error = errno;
-            VLOG_ERR("bind to %s failed: %s", suffix, strerror(error));
+            VLOG_ERR("bind to %s failed: %s", name, strerror(error));
             goto error;
         }
 
@@ -366,7 +853,7 @@ netdev_linux_recv(struct netdev *netdev_, void *data, size_t size)
 
     if (netdev->tap_fd < 0) {
         /* Device was opened with NETDEV_ETH_TYPE_NONE. */
-        return EAGAIN;
+        return -EAGAIN;
     }
 
     for (;;) {
@@ -378,7 +865,7 @@ netdev_linux_recv(struct netdev *netdev_, void *data, size_t size)
                 VLOG_WARN_RL(&rl, "error receiving Ethernet packet on %s: %s",
                              strerror(errno), netdev_get_name(netdev_));
             }
-            return errno;
+            return -errno;
         }
     }
 }
@@ -488,9 +975,17 @@ netdev_linux_set_etheraddr(struct netdev *netdev_,
                            const uint8_t mac[ETH_ADDR_LEN])
 {
     struct netdev_linux *netdev = netdev_linux_cast(netdev_);
-    int error = set_etheraddr(netdev_get_name(netdev_), ARPHRD_ETHER, mac);
-    if (!error) {
-        memcpy(netdev->cache->etheraddr, mac, ETH_ADDR_LEN);
+    int error;
+
+    if (!(netdev->cache->valid & VALID_ETHERADDR)
+        || !eth_addr_equals(netdev->cache->etheraddr, mac)) {
+        error = set_etheraddr(netdev_get_name(netdev_), ARPHRD_ETHER, mac);
+        if (!error) {
+            netdev->cache->valid |= VALID_ETHERADDR;
+            memcpy(netdev->cache->etheraddr, mac, ETH_ADDR_LEN);
+        }
+    } else {
+        error = 0;
     }
     return error;
 }
@@ -536,6 +1031,17 @@ netdev_linux_get_mtu(const struct netdev *netdev_, int *mtup)
     return 0;
 }
 
+/* Returns the ifindex of 'netdev', if successful, as a positive number.
+ * On failure, returns a negative errno value. */
+static int
+netdev_linux_get_ifindex(const struct netdev *netdev)
+{
+    int ifindex, error;
+
+    error = get_ifindex(netdev, &ifindex);
+    return error ? -error : ifindex;
+}
+
 static int
 netdev_linux_get_carrier(const struct netdev *netdev_, bool *carrier)
 {
@@ -625,33 +1131,90 @@ check_for_working_netlink_stats(void)
  * XXX All of the members of struct netdev_stats are 64 bits wide, but on
  * 32-bit architectures the Linux network stats are only 32 bits. */
 static int
-netdev_linux_get_stats(const struct netdev *netdev, struct netdev_stats *stats)
+netdev_linux_get_stats(const struct netdev *netdev_, struct netdev_stats *stats)
 {
+    struct netdev_linux *netdev = netdev_linux_cast(netdev_);
     static int use_netlink_stats = -1;
     int error;
+    struct netdev_stats raw_stats;
+    struct netdev_stats *collect_stats = stats;
 
     COVERAGE_INC(netdev_get_stats);
+
+    if (!(netdev->cache->valid & VALID_IS_INTERNAL)) {
+        netdev->cache->is_internal = (netdev->tap_fd != -1);
+
+        if (!netdev->cache->is_internal) {
+            struct ethtool_drvinfo drvinfo;
+
+            memset(&drvinfo, 0, sizeof drvinfo);
+            error = netdev_linux_do_ethtool(&netdev->netdev,
+                                            (struct ethtool_cmd *)&drvinfo,
+                                            ETHTOOL_GDRVINFO,
+                                            "ETHTOOL_GDRVINFO");
+
+            if (!error) {
+                netdev->cache->is_internal = !strcmp(drvinfo.driver,
+                                                     "openvswitch");
+            }
+        }
+
+        netdev->cache->valid |= VALID_IS_INTERNAL;
+    }
+
+    if (netdev->cache->is_internal) {
+        collect_stats = &raw_stats;
+    }
+
     if (use_netlink_stats < 0) {
         use_netlink_stats = check_for_working_netlink_stats();
     }
     if (use_netlink_stats) {
         int ifindex;
 
-        error = get_ifindex(netdev, &ifindex);
+        error = get_ifindex(&netdev->netdev, &ifindex);
         if (!error) {
-            error = get_stats_via_netlink(ifindex, stats);
+            error = get_stats_via_netlink(ifindex, collect_stats);
         }
     } else {
-        error = get_stats_via_proc(netdev->name, stats);
+        error = get_stats_via_proc(netdev->netdev.name, collect_stats);
+    }
+
+    /* If this port is an internal port then the transmit and receive stats
+     * will appear to be swapped relative to the other ports since we are the
+     * one sending the data, not a remote computer.  For consistency, we swap
+     * them back here. */
+    if (netdev->cache->is_internal) {
+        stats->rx_packets = raw_stats.tx_packets;
+        stats->tx_packets = raw_stats.rx_packets;
+        stats->rx_bytes = raw_stats.tx_bytes;
+        stats->tx_bytes = raw_stats.rx_bytes;
+        stats->rx_errors = raw_stats.tx_errors;
+        stats->tx_errors = raw_stats.rx_errors;
+        stats->rx_dropped = raw_stats.tx_dropped;
+        stats->tx_dropped = raw_stats.rx_dropped;
+        stats->multicast = raw_stats.multicast;
+        stats->collisions = raw_stats.collisions;
+        stats->rx_length_errors = 0;
+        stats->rx_over_errors = 0;
+        stats->rx_crc_errors = 0;
+        stats->rx_frame_errors = 0;
+        stats->rx_fifo_errors = 0;
+        stats->rx_missed_errors = 0;
+        stats->tx_aborted_errors = 0;
+        stats->tx_carrier_errors = 0;
+        stats->tx_fifo_errors = 0;
+        stats->tx_heartbeat_errors = 0;
+        stats->tx_window_errors = 0;
     }
+
     return error;
 }
 
 /* Stores the features supported by 'netdev' into each of '*current',
  * '*advertised', '*supported', and '*peer' that are non-null.  Each value is a
  * bitmap of "enum ofp_port_features" bits, in host byte order.  Returns 0 if
- * successful, otherwise a positive errno value.  On failure, all of the
- * passed-in values are set to 0. */
+ * successful, otherwise a positive errno value. */
 static int
 netdev_linux_get_features(struct netdev *netdev,
                           uint32_t *current, uint32_t *advertised,
@@ -1147,14 +1710,14 @@ netdev_linux_arp_lookup(const struct netdev *netdev,
                         uint32_t ip, uint8_t mac[ETH_ADDR_LEN])
 {
     struct arpreq r;
-    struct sockaddr_in *pa;
+    struct sockaddr_in sin;
     int retval;
 
     memset(&r, 0, sizeof r);
-    pa = (struct sockaddr_in *) &r.arp_pa;
-    pa->sin_family = AF_INET;
-    pa->sin_addr.s_addr = ip;
-    pa->sin_port = 0;
+    sin.sin_family = AF_INET;
+    sin.sin_addr.s_addr = ip;
+    sin.sin_port = 0;
+    memcpy(&r.arp_pa, &sin, sizeof sin);
     r.arp_ha.sa_family = ARPHRD_ETHER;
     r.arp_flags = 0;
     strncpy(r.arp_dev, netdev->name, sizeof r.arp_dev);
@@ -1297,13 +1860,16 @@ netdev_linux_poll_remove(struct netdev_notifier *notifier_)
 }
 
 const struct netdev_class netdev_linux_class = {
-    "",                         /* prefix */
-    "linux",                    /* name */
+    "system",                   /* type */
 
     netdev_linux_init,
     netdev_linux_run,
     netdev_linux_wait,
 
+    netdev_linux_create_system,
+    netdev_linux_destroy,
+    NULL,                       /* reconfigure */
+
     netdev_linux_open,
     netdev_linux_close,
 
@@ -1319,6 +1885,7 @@ const struct netdev_class netdev_linux_class = {
     netdev_linux_set_etheraddr,
     netdev_linux_get_etheraddr,
     netdev_linux_get_mtu,
+    netdev_linux_get_ifindex,
     netdev_linux_get_carrier,
     netdev_linux_get_stats,
 
@@ -1341,13 +1908,16 @@ const struct netdev_class netdev_linux_class = {
 };
 
 const struct netdev_class netdev_tap_class = {
-    "tap",                      /* prefix */
-    "tap",                      /* name */
+    "tap",                      /* type */
 
     netdev_linux_init,
     NULL,                       /* run */
     NULL,                       /* wait */
 
+    netdev_linux_create_tap,
+    netdev_linux_destroy,
+    NULL,                       /* reconfigure */
+
     netdev_linux_open,
     netdev_linux_close,
 
@@ -1363,6 +1933,55 @@ const struct netdev_class netdev_tap_class = {
     netdev_linux_set_etheraddr,
     netdev_linux_get_etheraddr,
     netdev_linux_get_mtu,
+    netdev_linux_get_ifindex,
+    netdev_linux_get_carrier,
+    netdev_linux_get_stats,
+
+    netdev_linux_get_features,
+    netdev_linux_set_advertisements,
+    netdev_linux_get_vlan_vid,
+    netdev_linux_set_policing,
+
+    netdev_linux_get_in4,
+    netdev_linux_set_in4,
+    netdev_linux_get_in6,
+    netdev_linux_add_router,
+    netdev_linux_get_next_hop,
+    netdev_linux_arp_lookup,
+
+    netdev_linux_update_flags,
+
+    netdev_linux_poll_add,
+    netdev_linux_poll_remove,
+};
+
+const struct netdev_class netdev_gre_class = {
+    "gre",                      /* type */
+
+    netdev_linux_init,
+    NULL,                       /* run */
+    NULL,                       /* wait */
+
+    netdev_linux_create_gre,
+    netdev_linux_destroy,
+    netdev_linux_reconfigure_gre,
+
+    netdev_linux_open,
+    netdev_linux_close,
+
+    netdev_linux_enumerate,
+
+    netdev_linux_recv,
+    netdev_linux_recv_wait,
+    netdev_linux_drain,
+
+    netdev_linux_send,
+    netdev_linux_send_wait,
+
+    netdev_linux_set_etheraddr,
+    netdev_linux_get_etheraddr,
+    netdev_linux_get_mtu,
+    netdev_linux_get_ifindex,
     netdev_linux_get_carrier,
     netdev_linux_get_stats,
 
@@ -1436,6 +2055,7 @@ get_stats_via_netlink(int ifindex, struct netdev_stats *stats)
 
     if (!attrs[IFLA_STATS]) {
         VLOG_WARN_RL(&rl, "RTM_GETLINK reply lacks stats");
+        ofpbuf_delete(reply);
         return EPROTO;
     }
 
@@ -1462,6 +2082,8 @@ get_stats_via_netlink(int ifindex, struct netdev_stats *stats)
     stats->tx_heartbeat_errors = rtnl_stats->tx_heartbeat_errors;
     stats->tx_window_errors = rtnl_stats->tx_window_errors;
 
+    ofpbuf_delete(reply);
+
     return 0;
 }