autocreate tap device for ethernet network type

If a user specify network type ethernet, then create it via libvirt and run
script if it provided. After this commit user does not need to
run external script to create tap device or add root permissions to qemu
process.

Signed-off-by: Vasiliy Tolstov <v.tolstov@selfip.ru>

diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index eb025530f20766217943d1e0508fc28d185a8c68..0331789b6b598e470594a6e5d616ba3080677980 100644 (file)
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3220,6 +3220,7 @@ qemuBuildHostNetStr(virDomainNetDefPtr net,
     case VIR_DOMAIN_NET_TYPE_BRIDGE:
     case VIR_DOMAIN_NET_TYPE_NETWORK:
     case VIR_DOMAIN_NET_TYPE_DIRECT:
+    case VIR_DOMAIN_NET_TYPE_ETHERNET:
         virBufferAsprintf(&buf, "tap%c", type_sep);
         /* for one tapfd 'fd=' shall be used,
          * for more than one 'fds=' is the right choice */
@@ -3237,20 +3238,6 @@ qemuBuildHostNetStr(virDomainNetDefPtr net,
         is_tap = true;
         break;
 
-    case VIR_DOMAIN_NET_TYPE_ETHERNET:
-        virBufferAddLit(&buf, "tap");
-        if (net->ifname) {
-            virBufferAsprintf(&buf, "%cifname=%s", type_sep, net->ifname);
-            type_sep = ',';
-        }
-        if (net->script) {
-            virBufferAsprintf(&buf, "%cscript=%s", type_sep,
-                              net->script);
-            type_sep = ',';
-        }
-        is_tap = true;
-        break;
-
     case VIR_DOMAIN_NET_TYPE_CLIENT:
        virBufferAsprintf(&buf, "socket%cconnect=%s:%d",
                          type_sep,
@@ -7792,7 +7779,8 @@ qemuBuildInterfaceCommandLine(virCommandPtr cmd,
     if (net->driver.virtio.queues > 0 &&
         !(actualType == VIR_DOMAIN_NET_TYPE_NETWORK ||
           actualType == VIR_DOMAIN_NET_TYPE_BRIDGE ||
-          actualType == VIR_DOMAIN_NET_TYPE_DIRECT)) {
+          actualType == VIR_DOMAIN_NET_TYPE_DIRECT ||
+          actualType == VIR_DOMAIN_NET_TYPE_ETHERNET)) {
         virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
                        _("Multiqueue network is not supported for: %s"),
                        virDomainNetTypeToString(actualType));
@@ -7802,7 +7790,8 @@ qemuBuildInterfaceCommandLine(virCommandPtr cmd,
     /* and only TAP devices support nwfilter rules */
     if (net->filter &&
         !(actualType == VIR_DOMAIN_NET_TYPE_NETWORK ||
-          actualType == VIR_DOMAIN_NET_TYPE_BRIDGE)) {
+          actualType == VIR_DOMAIN_NET_TYPE_BRIDGE ||
+          actualType == VIR_DOMAIN_NET_TYPE_ETHERNET)) {
         virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
                        _("filterref is not supported for "
                          "network interfaces of type %s"),
@@ -7812,7 +7801,8 @@ qemuBuildInterfaceCommandLine(virCommandPtr cmd,
 
     if (net->backend.tap &&
         !(actualType == VIR_DOMAIN_NET_TYPE_NETWORK ||
-          actualType == VIR_DOMAIN_NET_TYPE_BRIDGE)) {
+          actualType == VIR_DOMAIN_NET_TYPE_BRIDGE ||
+          actualType == VIR_DOMAIN_NET_TYPE_ETHERNET)) {
         virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
                        _("Custom tap device path is not supported for: %s"),
                        virDomainNetTypeToString(actualType));
@@ -7850,6 +7840,20 @@ qemuBuildInterfaceCommandLine(virCommandPtr cmd,
         if (qemuInterfaceDirectConnect(def, driver, net,
                                        tapfd, tapfdSize, vmop) < 0)
             goto cleanup;
+    } else if (actualType == VIR_DOMAIN_NET_TYPE_ETHERNET) {
+        tapfdSize = net->driver.virtio.queues;
+        if (!tapfdSize)
+            tapfdSize = 1;
+
+        if (VIR_ALLOC_N(tapfd, tapfdSize) < 0 ||
+            VIR_ALLOC_N(tapfdName, tapfdSize) < 0)
+            goto cleanup;
+
+        memset(tapfd, -1, tapfdSize * sizeof(tapfd[0]));
+
+        if (qemuInterfaceEthernetConnect(def, driver, net,
+                                       tapfd, tapfdSize) < 0)
+            goto cleanup;
     }
 
     /* For types whose implementations use a netdev on the host, add

diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
index a78bc60d587332dd296eb0bdf09c01128eb8b1fe..f5809064f2c9c5873be4e4037b62a721b507c232 100644 (file)
--- a/src/qemu/qemu_hotplug.c
+++ b/src/qemu/qemu_hotplug.c
@@ -895,7 +895,8 @@ int qemuDomainAttachNetDevice(virConnectPtr conn,
     if (net->driver.virtio.queues > 0 &&
         !(actualType == VIR_DOMAIN_NET_TYPE_NETWORK ||
           actualType == VIR_DOMAIN_NET_TYPE_BRIDGE ||
-          actualType == VIR_DOMAIN_NET_TYPE_DIRECT)) {
+          actualType == VIR_DOMAIN_NET_TYPE_DIRECT ||
+          actualType == VIR_DOMAIN_NET_TYPE_ETHERNET)) {
         virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
                        _("Multiqueue network is not supported for: %s"),
                        virDomainNetTypeToString(actualType));
@@ -905,7 +906,8 @@ int qemuDomainAttachNetDevice(virConnectPtr conn,
     /* and only TAP devices support nwfilter rules */
     if (net->filter &&
         !(actualType == VIR_DOMAIN_NET_TYPE_NETWORK ||
-          actualType == VIR_DOMAIN_NET_TYPE_BRIDGE)) {
+          actualType == VIR_DOMAIN_NET_TYPE_BRIDGE ||
+          actualType == VIR_DOMAIN_NET_TYPE_ETHERNET)) {
         virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
                        _("filterref is not supported for "
                          "network interfaces of type %s"),
@@ -950,10 +952,19 @@ int qemuDomainAttachNetDevice(virConnectPtr conn,
                                       vhostfd, &vhostfdSize) < 0)
             goto cleanup;
     } else if (actualType == VIR_DOMAIN_NET_TYPE_ETHERNET) {
-        vhostfdSize = 1;
-        if (VIR_ALLOC(vhostfd) < 0)
+        tapfdSize = vhostfdSize = net->driver.virtio.queues;
+        if (!tapfdSize)
+            tapfdSize = vhostfdSize = 1;
+        if (VIR_ALLOC_N(tapfd, tapfdSize) < 0)
             goto cleanup;
-        *vhostfd = -1;
+        memset(tapfd, -1, sizeof(*tapfd) * tapfdSize);
+        if (VIR_ALLOC_N(vhostfd, vhostfdSize) < 0)
+            goto cleanup;
+        memset(vhostfd, -1, sizeof(*vhostfd) * vhostfdSize);
+        if (qemuInterfaceEthernetConnect(vm->def, driver, net,
+                                       tapfd, tapfdSize) < 0)
+            goto cleanup;
+        iface_connected = true;
         if (qemuInterfaceOpenVhostNet(vm->def, net, priv->qemuCaps,
                                       vhostfd, &vhostfdSize) < 0)
             goto cleanup;
@@ -2204,6 +2215,21 @@ int qemuDomainChangeNetLinkState(virQEMUDriverPtr driver,
     if (ret < 0)
         goto cleanup;
 
+    if (virDomainNetGetActualType(dev) == VIR_DOMAIN_NET_TYPE_ETHERNET) {
+        switch (linkstate) {
+            case VIR_DOMAIN_NET_INTERFACE_LINK_STATE_UP:
+            case VIR_DOMAIN_NET_INTERFACE_LINK_STATE_DEFAULT:
+                if ((ret = virNetDevSetOnline(dev->ifname, true)) < 0)
+                    goto cleanup;
+                break;
+
+            case VIR_DOMAIN_NET_INTERFACE_LINK_STATE_DOWN:
+                if ((ret = virNetDevSetOnline(dev->ifname, false)) < 0)
+                    goto cleanup;
+                break;
+            }
+    }
+
     /* modify the device configuration */
     dev->linkstate = linkstate;
 

diff --git a/src/qemu/qemu_interface.c b/src/qemu/qemu_interface.c
index 08af13358113b5e778c0e9b6c9ce9bbf8b72c90c..13a513152876d381f77460733a91df4706f6bc41 100644 (file)
--- a/src/qemu/qemu_interface.c
+++ b/src/qemu/qemu_interface.c
@@ -387,6 +387,124 @@ qemuCreateInBridgePortWithHelper(virQEMUDriverConfigPtr cfg,
     return *tapfd < 0 ? -1 : 0;
 }
 
+/**
+ * qemuExecuteEthernetScript:
+ * @ifname: the interface name
+ * @script: the script name
+ *
+ * This function executes script for new tap device created by libvirt.
+ * Returns 0 in case of success or -1 on failure
+ */
+static int
+qemuExecuteEthernetScript(const char *ifname, const char *script)
+{
+        virCommandPtr cmd;
+        int ret;
+
+        cmd = virCommandNew(script);
+        virCommandAddArgFormat(cmd, "%s", ifname);
+        virCommandClearCaps(cmd);
+#ifdef CAP_NET_ADMIN
+        virCommandAllowCap(cmd, CAP_NET_ADMIN);
+#endif
+        virCommandAddEnvPassCommon(cmd);
+
+        ret = virCommandRun(cmd, NULL);
+
+        virCommandFree(cmd);
+        return ret;
+}
+
+/* qemuInterfaceEthernetConnect:
+ * @def: the definition of the VM
+ * @driver: qemu driver data
+ * @net: pointer to the VM's interface description
+ * @tapfd: array of file descriptor return value for the new device
+ * @tapfdsize: number of file descriptors in @tapfd
+ *
+ * Called *only* called if actualType is VIR_DOMAIN_NET_TYPE_ETHERNET
+ * (i.e. if the connection is made with a tap device)
+ */
+int
+qemuInterfaceEthernetConnect(virDomainDefPtr def,
+                           virQEMUDriverPtr driver,
+                           virDomainNetDefPtr net,
+                           int *tapfd,
+                           size_t tapfdSize)
+{
+    virMacAddr tapmac;
+    int ret = -1;
+    unsigned int tap_create_flags = VIR_NETDEV_TAP_CREATE_IFUP;
+    bool template_ifname = false;
+    virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver);
+    const char *tunpath = "/dev/net/tun";
+
+    if (net->backend.tap) {
+        tunpath = net->backend.tap;
+        if (!virQEMUDriverIsPrivileged(driver)) {
+            virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                           _("cannot use custom tap device in session mode"));
+            goto cleanup;
+        }
+    }
+
+    if (!net->ifname ||
+        STRPREFIX(net->ifname, VIR_NET_GENERATED_PREFIX) ||
+        strchr(net->ifname, '%')) {
+        VIR_FREE(net->ifname);
+        if (VIR_STRDUP(net->ifname, VIR_NET_GENERATED_PREFIX "%d") < 0)
+            goto cleanup;
+        /* avoid exposing vnet%d in getXMLDesc or error outputs */
+        template_ifname = true;
+    }
+
+    if (net->model && STREQ(net->model, "virtio"))
+        tap_create_flags |= VIR_NETDEV_TAP_CREATE_VNET_HDR;
+
+    if (virNetDevTapCreate(&net->ifname, tunpath, tapfd, tapfdSize,
+                           tap_create_flags) < 0) {
+        virDomainAuditNetDevice(def, net, tunpath, false);
+        goto cleanup;
+    }
+
+    virDomainAuditNetDevice(def, net, tunpath, true);
+    virMacAddrSet(&tapmac, &net->mac);
+    tapmac.addr[0] = 0xFE;
+
+    if (virNetDevSetMAC(net->ifname, &tapmac) < 0)
+        goto cleanup;
+
+    if (net->script &&
+        qemuExecuteEthernetScript(net->ifname, net->script) < 0)
+        goto cleanup;
+
+    if (cfg->macFilter &&
+        ebtablesAddForwardAllowIn(driver->ebtables,
+                                  net->ifname,
+                                  &net->mac) < 0)
+        goto cleanup;
+
+    if (net->filter &&
+        virDomainConfNWFilterInstantiate(def->uuid, net) < 0) {
+        goto cleanup;
+    }
+
+    ret = 0;
+
+ cleanup:
+    if (ret < 0) {
+        size_t i;
+        for (i = 0; i < tapfdSize && tapfd[i] >= 0; i++)
+            VIR_FORCE_CLOSE(tapfd[i]);
+        if (template_ifname)
+            VIR_FREE(net->ifname);
+    }
+    virObjectUnref(cfg);
+
+    return ret;
+}
+
+
 /* qemuInterfaceBridgeConnect:
  * @def: the definition of the VM
  * @driver: qemu driver data

diff --git a/src/qemu/qemu_interface.h b/src/qemu/qemu_interface.h
index bf4dedf84ac9dd600a6073d587d111c582ed63ec..66ead2aef81ca4859aa40787f9d0c42a26f6f4a7 100644 (file)
--- a/src/qemu/qemu_interface.h
+++ b/src/qemu/qemu_interface.h
@@ -40,6 +40,11 @@ int qemuInterfaceDirectConnect(virDomainDefPtr def,
                                 int *tapfd,
                                 size_t tapfdSize,
                                 virNetDevVPortProfileOp vmop);
+int qemuInterfaceEthernetConnect(virDomainDefPtr def,
+                               virQEMUDriverPtr driver,
+                               virDomainNetDefPtr net,
+                               int *tapfd,
+                               size_t tapfdSize);
 
 int qemuInterfaceBridgeConnect(virDomainDefPtr def,
                                virQEMUDriverPtr driver,

diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index fa05b2c831b32093789a0e0490c3d2062eb62d2e..6ec7b76694db4a06926a8155164be9cbe0ebafa5 100644 (file)
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -5847,6 +5847,12 @@ void qemuProcessStop(virQEMUDriverPtr driver,
                              virDomainNetGetActualVirtPortProfile(net),
                              cfg->stateDir));
             break;
+        case VIR_DOMAIN_NET_TYPE_ETHERNET:
+            if (net->ifname) {
+                ignore_value(virNetDevTapDelete(net->ifname, net->backend.tap));
+                VIR_FREE(net->ifname);
+            }
+            break;
         case VIR_DOMAIN_NET_TYPE_BRIDGE:
         case VIR_DOMAIN_NET_TYPE_NETWORK:
 #ifdef VIR_NETDEV_TAP_REQUIRE_MANUAL_CLEANUP