libvirt/tools/virsh-interface.c

/*
 * virsh-interface.c: Commands to manage host interface
 *
 * Copyright (C) 2005, 2007-2016 Red Hat, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library.  If not, see
 * <http://www.gnu.org/licenses/>.
 */

#define VIRSH_COMMON_OPT_INTERFACE(cflags) \
    {.name = "interface", \
     .type = VSH_OT_DATA, \
     .positional = true, \
     .required = true, \
     .flags = VSH_OFLAG_REQ, \
     .help = N_("interface name or MAC address"), \
     .completer = virshInterfaceNameCompleter, \
     .completer_flags = cflags, \
    }

#include <config.h>
#include "virsh-interface.h"
#include "virsh-util.h"

#include <libxml/parser.h>
#include <libxml/xpath.h>

#include "internal.h"
#include "viralloc.h"
#include "virfile.h"
#include "virmacaddr.h"
#include "virxml.h"
#include "vsh-table.h"

virInterfacePtr
virshCommandOptInterfaceBy(vshControl *ctl, const vshCmd *cmd,
                           const char *optname,
                           const char **name, unsigned int flags)
{
    virInterfacePtr iface = NULL;
    const char *n = NULL;
    bool is_mac = false;
    virMacAddr dummy;
    virshControl *priv = ctl->privData;

    virCheckFlags(VIRSH_BYNAME | VIRSH_BYMAC, NULL);

    if (!optname)
       optname = "interface";

    if (vshCommandOptStringReq(ctl, cmd, optname, &n) < 0)
        return NULL;

    vshDebug(ctl, VSH_ERR_INFO, "%s: found option <%s>: %s\n",
             cmd->def->name, optname, n);

    if (name)
        *name = n;

    if (virMacAddrParse(n, &dummy) == 0)
        is_mac = true;

    /* try it by NAME */
    if (!is_mac && (flags & VIRSH_BYNAME)) {
        vshDebug(ctl, VSH_ERR_DEBUG, "%s: <%s> trying as interface NAME\n",
                 cmd->def->name, optname);
        iface = virInterfaceLookupByName(priv->conn, n);

    /* try it by MAC */
    } else if (is_mac && (flags & VIRSH_BYMAC)) {
        vshDebug(ctl, VSH_ERR_DEBUG, "%s: <%s> trying as interface MAC\n",
                 cmd->def->name, optname);
        iface = virInterfaceLookupByMACString(priv->conn, n);
    }

    if (!iface)
        vshError(ctl, _("failed to get interface '%1$s'"), n);

    return iface;
}

/*
 * "iface-edit" command
 */
static const vshCmdInfo info_interface_edit = {
    .help = N_("edit XML configuration for a physical host interface"),
    .desc = N_("Edit the XML configuration for a physical host interface."),
};

static const vshCmdOptDef opts_interface_edit[] = {
    VIRSH_COMMON_OPT_INTERFACE(0),
    {.name = NULL}
};

static bool
cmdInterfaceEdit(vshControl *ctl, const vshCmd *cmd)
{
    bool ret = false;
    g_autoptr(virshInterface) iface = NULL;
    g_autoptr(virshInterface) iface_edited = NULL;
    unsigned int flags = VIR_INTERFACE_XML_INACTIVE;
    virshControl *priv = ctl->privData;

    iface = virshCommandOptInterface(ctl, cmd, NULL);
    if (iface == NULL)
        goto cleanup;

#define EDIT_GET_XML virInterfaceGetXMLDesc(iface, flags)
#define EDIT_NOT_CHANGED \
    do { \
        vshPrintExtra(ctl, _("Interface %1$s XML configuration not changed.\n"), \
                 virInterfaceGetName(iface)); \
        ret = true; \
        goto edit_cleanup; \
    } while (0)
#define EDIT_DEFINE \
    (iface_edited = virInterfaceDefineXML(priv->conn, doc_edited, 0))
#include "virsh-edit.c"

    vshPrintExtra(ctl, _("Interface %1$s XML configuration edited.\n"),
                  virInterfaceGetName(iface_edited));

    ret = true;

 cleanup:
    return ret;
}

static int
virshInterfaceSorter(const void *a,
                     const void *b,
                     void *opaque G_GNUC_UNUSED)
{
    virInterfacePtr *ia = (virInterfacePtr *) a;
    virInterfacePtr *ib = (virInterfacePtr *) b;

    if (*ia && !*ib)
        return -1;

    if (!*ia)
        return *ib != NULL;

    return vshStrcasecmp(virInterfaceGetName(*ia),
                      virInterfaceGetName(*ib));
}

struct virshInterfaceList {
    virInterfacePtr *ifaces;
    size_t nifaces;
};

static void
virshInterfaceListFree(struct virshInterfaceList *list)
{
    size_t i;

    if (list && list->ifaces) {
        for (i = 0; i < list->nifaces; i++) {
            virshInterfaceFree(list->ifaces[i]);
        }
        g_free(list->ifaces);
    }
    g_free(list);
}

static struct virshInterfaceList *
virshInterfaceListCollect(vshControl *ctl,
                          unsigned int flags)
{
    struct virshInterfaceList *list = g_new0(struct virshInterfaceList, 1);
    size_t i;
    int ret;
    char **activeNames = NULL;
    char **inactiveNames = NULL;
    virInterfacePtr iface;
    bool success = false;
    size_t deleted = 0;
    int nActiveIfaces = 0;
    int nInactiveIfaces = 0;
    int nAllIfaces = 0;
    virshControl *priv = ctl->privData;

    /* try the list with flags support (0.10.2 and later) */
    if ((ret = virConnectListAllInterfaces(priv->conn,
                                           &list->ifaces,
                                           flags)) >= 0) {
        list->nifaces = ret;
        goto finished;
    }

    /* check if the command is actually supported */
    if (last_error && last_error->code == VIR_ERR_NO_SUPPORT)
        goto fallback;

    /* there was an error during the first or second call */
    vshError(ctl, "%s", _("Failed to list interfaces"));
    goto cleanup;


 fallback:
    /* fall back to old method (0.10.1 and older) */
    vshResetLibvirtError();

    if (flags & VIR_CONNECT_LIST_INTERFACES_ACTIVE) {
        nActiveIfaces = virConnectNumOfInterfaces(priv->conn);
        if (nActiveIfaces < 0) {
            vshError(ctl, "%s", _("Failed to list active interfaces"));
            goto cleanup;
        }
        if (nActiveIfaces) {
            activeNames = g_new0(char *, nActiveIfaces);

            if ((nActiveIfaces = virConnectListInterfaces(priv->conn, activeNames,
                                                          nActiveIfaces)) < 0) {
                vshError(ctl, "%s", _("Failed to list active interfaces"));
                goto cleanup;
            }
        }
    }

    if (flags & VIR_CONNECT_LIST_INTERFACES_INACTIVE) {
        nInactiveIfaces = virConnectNumOfDefinedInterfaces(priv->conn);
        if (nInactiveIfaces < 0) {
            vshError(ctl, "%s", _("Failed to list inactive interfaces"));
            goto cleanup;
        }
        if (nInactiveIfaces) {
            inactiveNames = g_new0(char *, nInactiveIfaces);

            if ((nInactiveIfaces =
                     virConnectListDefinedInterfaces(priv->conn, inactiveNames,
                                                     nInactiveIfaces)) < 0) {
                vshError(ctl, "%s", _("Failed to list inactive interfaces"));
                goto cleanup;
            }
        }
    }

    nAllIfaces = nActiveIfaces + nInactiveIfaces;
    if (nAllIfaces == 0) {
        VIR_FREE(activeNames);
        VIR_FREE(inactiveNames);
        return list;
    }

    list->ifaces = g_new0(virInterfacePtr, nAllIfaces);
    list->nifaces = 0;

    /* get active interfaces */
    for (i = 0; i < nActiveIfaces; i++) {
        if (!(iface = virInterfaceLookupByName(priv->conn, activeNames[i]))) {
            vshResetLibvirtError();
            continue;
        }
        list->ifaces[list->nifaces++] = iface;
    }

    /* get inactive interfaces */
    for (i = 0; i < nInactiveIfaces; i++) {
        if (!(iface = virInterfaceLookupByName(priv->conn, inactiveNames[i]))) {
            vshResetLibvirtError();
            continue;
        }
        list->ifaces[list->nifaces++] = iface;
    }

    /* truncate interfaces that weren't found */
    deleted = nAllIfaces - list->nifaces;

 finished:
    /* sort the list */
    if (list->ifaces && list->nifaces) {
        g_qsort_with_data(list->ifaces, list->nifaces,
                          sizeof(*list->ifaces), virshInterfaceSorter, NULL);
    }

    /* truncate the list if filter simulation deleted entries */
    if (deleted)
        VIR_SHRINK_N(list->ifaces, list->nifaces, deleted);

    success = true;

 cleanup:
    for (i = 0; nActiveIfaces != -1 && i < nActiveIfaces; i++)
        VIR_FREE(activeNames[i]);

    for (i = 0; nInactiveIfaces != -1 && i < nInactiveIfaces; i++)
        VIR_FREE(inactiveNames[i]);

    VIR_FREE(activeNames);
    VIR_FREE(inactiveNames);

    if (!success) {
        g_clear_pointer(&list, virshInterfaceListFree);
    }

    return list;
}

/*
 * "iface-list" command
 */
static const vshCmdInfo info_interface_list = {
    .help = N_("list physical host interfaces"),
    .desc = N_("Returns list of physical host interfaces."),
};

static const vshCmdOptDef opts_interface_list[] = {
    {.name = "inactive",
     .type = VSH_OT_BOOL,
     .help = N_("list inactive interfaces")
    },
    {.name = "all",
     .type = VSH_OT_BOOL,
     .help = N_("list inactive & active interfaces")
    },
    {.name = NULL}
};

static bool
cmdInterfaceList(vshControl *ctl, const vshCmd *cmd G_GNUC_UNUSED)
{
    bool inactive = vshCommandOptBool(cmd, "inactive");
    bool all = vshCommandOptBool(cmd, "all");
    unsigned int flags = VIR_CONNECT_LIST_INTERFACES_ACTIVE;
    struct virshInterfaceList *list = NULL;
    size_t i;
    bool ret = false;
    g_autoptr(vshTable) table = NULL;

    VSH_EXCLUSIVE_OPTIONS_VAR(all, inactive);

    if (inactive)
        flags = VIR_CONNECT_LIST_INTERFACES_INACTIVE;
    if (all)
        flags = VIR_CONNECT_LIST_INTERFACES_INACTIVE |
                VIR_CONNECT_LIST_INTERFACES_ACTIVE;

    if (!(list = virshInterfaceListCollect(ctl, flags)))
        return false;

    table = vshTableNew(_("Name"), _("State"), _("MAC Address"), NULL);
    if (!table)
        goto cleanup;

    for (i = 0; i < list->nifaces; i++) {
        virInterfacePtr iface = list->ifaces[i];

        if (vshTableRowAppend(table,
                              virInterfaceGetName(iface),
                              virInterfaceIsActive(iface) ? _("active")
                              : _("inactive"),
                              virInterfaceGetMACString(iface),
                              NULL) < 0)
            goto cleanup;
    }

    vshTablePrintToStdout(table, ctl);

    ret = true;
 cleanup:
    virshInterfaceListFree(list);
    return ret;
}

/*
 * "iface-name" command
 */
static const vshCmdInfo info_interface_name = {
    .help = N_("convert an interface MAC address to interface name"),
    .desc = "",
};

static const vshCmdOptDef opts_interface_name[] = {
    {.name = "interface",
     .type = VSH_OT_DATA,
     .positional = true,
     .required = true,
     .flags = VSH_OFLAG_REQ,
     .completer = virshInterfaceMacCompleter,
     .help = N_("interface mac")
    },
    {.name = NULL}
};

static bool
cmdInterfaceName(vshControl *ctl, const vshCmd *cmd)
{
    g_autoptr(virshInterface) iface = NULL;

    if (!(iface = virshCommandOptInterfaceBy(ctl, cmd, NULL, NULL,
                                             VIRSH_BYMAC)))
        return false;

    vshPrint(ctl, "%s\n", virInterfaceGetName(iface));
    return true;
}

/*
 * "iface-mac" command
 */
static const vshCmdInfo info_interface_mac = {
    .help = N_("convert an interface name to interface MAC address"),
    .desc = "",
};

static const vshCmdOptDef opts_interface_mac[] = {
    {.name = "interface",
     .type = VSH_OT_DATA,
     .positional = true,
     .required = true,
     .flags = VSH_OFLAG_REQ,
     .completer = virshInterfaceNameCompleter,
     .help = N_("interface name")
    },
    {.name = NULL}
};

static bool
cmdInterfaceMAC(vshControl *ctl, const vshCmd *cmd)
{
    g_autoptr(virshInterface) iface = NULL;

    if (!(iface = virshCommandOptInterfaceBy(ctl, cmd, NULL, NULL,
                                             VIRSH_BYNAME)))
        return false;

    vshPrint(ctl, "%s\n", virInterfaceGetMACString(iface));
    return true;
}

/*
 * "iface-dumpxml" command
 */
static const vshCmdInfo info_interface_dumpxml = {
    .help = N_("interface information in XML"),
    .desc = N_("Output the physical host interface information as an XML dump to stdout."),
};

static const vshCmdOptDef opts_interface_dumpxml[] = {
    VIRSH_COMMON_OPT_INTERFACE(0),
    {.name = "inactive",
     .type = VSH_OT_BOOL,
     .help = N_("show inactive defined XML")
    },
    {.name = "xpath",
     .type = VSH_OT_STRING,
     .flags = VSH_OFLAG_REQ_OPT,
     .completer = virshCompleteEmpty,
     .help = N_("xpath expression to filter the XML document")
    },
    {.name = "wrap",
     .type = VSH_OT_BOOL,
     .help = N_("wrap xpath results in an common root element"),
    },

    {.name = NULL}
};

static bool
cmdInterfaceDumpXML(vshControl *ctl, const vshCmd *cmd)
{
    g_autoptr(virshInterface) iface = NULL;
    g_autofree char *xml = NULL;
    bool wrap = vshCommandOptBool(cmd, "wrap");
    const char *xpath = NULL;
    unsigned int flags = 0;

    if (vshCommandOptBool(cmd, "inactive"))
        flags |= VIR_INTERFACE_XML_INACTIVE;

    if (!(iface = virshCommandOptInterface(ctl, cmd, NULL)))
        return false;

    if (vshCommandOptStringQuiet(ctl, cmd, "xpath", &xpath) < 0)
        return false;

    if (!(xml = virInterfaceGetXMLDesc(iface, flags)))
        return false;

    return virshDumpXML(ctl, xml, "interface", xpath, wrap);
}

/*
 * "iface-define" command
 */
static const vshCmdInfo info_interface_define = {
     .help = N_("define an inactive persistent physical host interface or "
                "modify an existing persistent one from an XML file"),
     .desc = N_("Define or modify a persistent physical host interface."),
};

static const vshCmdOptDef opts_interface_define[] = {
    VIRSH_COMMON_OPT_FILE(N_("file containing an XML interface description")),
    {.name = "validate",
     .type = VSH_OT_BOOL,
     .help = N_("validate the XML against the schema")
    },
    {.name = NULL}
};

static bool
cmdInterfaceDefine(vshControl *ctl, const vshCmd *cmd)
{
    g_autoptr(virshInterface) iface = NULL;
    const char *from = NULL;
    g_autofree char *buffer = NULL;
    unsigned int flags = 0;
    virshControl *priv = ctl->privData;

    if (vshCommandOptStringReq(ctl, cmd, "file", &from) < 0)
        return false;

    if (vshCommandOptBool(cmd, "validate"))
        flags |= VIR_INTERFACE_DEFINE_VALIDATE;

    if (virFileReadAll(from, VSH_MAX_XML_FILE, &buffer) < 0)
        return false;

    if (!(iface = virInterfaceDefineXML(priv->conn, buffer, flags))) {
        vshError(ctl, _("Failed to define interface from %1$s"), from);
        return false;
    }

    vshPrintExtra(ctl, _("Interface %1$s defined from %2$s\n"),
                  virInterfaceGetName(iface), from);
    return true;
}

/*
 * "iface-undefine" command
 */
static const vshCmdInfo info_interface_undefine = {
    .help = N_("undefine a physical host interface (remove it from configuration)"),
    .desc = N_("undefine an interface."),
};

static const vshCmdOptDef opts_interface_undefine[] = {
    VIRSH_COMMON_OPT_INTERFACE(0),
    {.name = NULL}
};

static bool
cmdInterfaceUndefine(vshControl *ctl, const vshCmd *cmd)
{
    g_autoptr(virshInterface) iface = NULL;
    const char *name;

    if (!(iface = virshCommandOptInterface(ctl, cmd, &name)))
        return false;

    if (virInterfaceUndefine(iface) < 0) {
        vshError(ctl, _("Failed to undefine interface %1$s"), name);
        return false;
    }

    vshPrintExtra(ctl, _("Interface %1$s undefined\n"), name);
    return true;
}

/*
 * "iface-start" command
 */
static const vshCmdInfo info_interface_start = {
    .help = N_("start a physical host interface (enable it / \"if-up\")"),
    .desc = N_("start a physical host interface."),
};

static const vshCmdOptDef opts_interface_start[] = {
    VIRSH_COMMON_OPT_INTERFACE(VIR_CONNECT_LIST_INTERFACES_INACTIVE),
    {.name = NULL}
};

static bool
cmdInterfaceStart(vshControl *ctl, const vshCmd *cmd)
{
    g_autoptr(virshInterface) iface = NULL;
    const char *name;

    if (!(iface = virshCommandOptInterface(ctl, cmd, &name)))
        return false;

    if (virInterfaceCreate(iface, 0) < 0) {
        vshError(ctl, _("Failed to start interface %1$s"), name);
        return false;
    }

    vshPrintExtra(ctl, _("Interface %1$s started\n"), name);
    return true;
}

/*
 * "iface-destroy" command
 */
static const vshCmdInfo info_interface_destroy = {
    .help = N_("destroy a physical host interface (disable it / \"if-down\")"),
    .desc = N_("forcefully stop a physical host interface."),
};

static const vshCmdOptDef opts_interface_destroy[] = {
    VIRSH_COMMON_OPT_INTERFACE(VIR_CONNECT_LIST_INTERFACES_ACTIVE),
    {.name = NULL}
};

static bool
cmdInterfaceDestroy(vshControl *ctl, const vshCmd *cmd)
{
    g_autoptr(virshInterface) iface = NULL;
    const char *name;

    if (!(iface = virshCommandOptInterface(ctl, cmd, &name)))
        return false;

    if (virInterfaceDestroy(iface, 0) < 0) {
        vshError(ctl, _("Failed to destroy interface %1$s"), name);
        return false;
    }

    vshPrintExtra(ctl, _("Interface %1$s destroyed\n"), name);
    return false;
}

/*
 * "iface-begin" command
 */
static const vshCmdInfo info_interface_begin = {
     .help = N_("create a snapshot of current interfaces settings, "
                "which can be later committed (iface-commit) or "
                "restored (iface-rollback)"),
     .desc = N_("Create a restore point for interfaces settings"),
};

static const vshCmdOptDef opts_interface_begin[] = {
    {.name = NULL}
};

static bool
cmdInterfaceBegin(vshControl *ctl, const vshCmd *cmd G_GNUC_UNUSED)
{
    virshControl *priv = ctl->privData;

    if (virInterfaceChangeBegin(priv->conn, 0) < 0) {
        vshError(ctl, "%s", _("Failed to begin network config change transaction"));
        return false;
    }

    vshPrintExtra(ctl, "%s", _("Network config change transaction started\n"));
    return true;
}

/*
 * "iface-commit" command
 */
static const vshCmdInfo info_interface_commit = {
    .help = N_("commit changes made since iface-begin and free restore point"),
    .desc = N_("commit changes and free restore point"),
};

static const vshCmdOptDef opts_interface_commit[] = {
    {.name = NULL}
};

static bool
cmdInterfaceCommit(vshControl *ctl, const vshCmd *cmd G_GNUC_UNUSED)
{
    virshControl *priv = ctl->privData;

    if (virInterfaceChangeCommit(priv->conn, 0) < 0) {
        vshError(ctl, "%s", _("Failed to commit network config change transaction"));
        return false;
    }

    vshPrintExtra(ctl, "%s", _("Network config change transaction committed\n"));
    return true;
}

/*
 * "iface-rollback" command
 */
static const vshCmdInfo info_interface_rollback = {
    .help = N_("rollback to previous saved configuration created via iface-begin"),
    .desc = N_("rollback to previous restore point"),
};

static const vshCmdOptDef opts_interface_rollback[] = {
    {.name = NULL}
};

static bool
cmdInterfaceRollback(vshControl *ctl, const vshCmd *cmd G_GNUC_UNUSED)
{
    virshControl *priv = ctl->privData;

    if (virInterfaceChangeRollback(priv->conn, 0) < 0) {
        vshError(ctl, "%s", _("Failed to rollback network config change transaction"));
        return false;
    }

    vshPrintExtra(ctl, "%s", _("Network config change transaction rolled back\n"));
    return true;
}

/*
 * "iface-bridge" command
 */
static const vshCmdInfo info_interface_bridge = {
    .help = N_("create a bridge device and attach an existing network device to it"),
    .desc = N_("bridge an existing network device"),
};

static const vshCmdOptDef opts_interface_bridge[] = {
    {.name = "interface",
     .type = VSH_OT_DATA,
     .positional = true,
     .required = true,
     .flags = VSH_OFLAG_REQ,
     .completer = virshInterfaceNameCompleter,
     .help = N_("existing interface name")
    },
    {.name = "bridge",
     .type = VSH_OT_DATA,
     .positional = true,
     .required = true,
     .flags = VSH_OFLAG_REQ,
     .help = N_("new bridge device name")
    },
    {.name = "no-stp",
     .type = VSH_OT_BOOL,
     .help = N_("do not enable STP for this bridge")
    },
    {.name = "delay",
     .type = VSH_OT_INT,
     .help = N_("number of seconds to squelch traffic on newly connected ports")
    },
    {.name = "no-start",
     .type = VSH_OT_BOOL,
     .help = N_("don't start the bridge immediately")
    },
    {.name = NULL}
};

static bool
cmdInterfaceBridge(vshControl *ctl, const vshCmd *cmd)
{
    bool ret = false;
    g_autoptr(virshInterface) if_handle = NULL;
    g_autoptr(virshInterface) br_handle = NULL;
    const char *if_name, *br_name;
    char *if_type = NULL, *if2_name = NULL, *delay_str = NULL;
    bool stp = false, nostart = false;
    unsigned int delay = 0;
    char *if_xml = NULL;
    xmlChar *br_xml = NULL;
    int br_xml_size;
    g_autoptr(xmlDoc) xml_doc = NULL;
    g_autoptr(xmlXPathContext) ctxt = NULL;
    xmlNodePtr top_node, br_node, if_node, cur;
    virshControl *priv = ctl->privData;

    /* Get a handle to the original device */
    if (!(if_handle = virshCommandOptInterfaceBy(ctl, cmd, "interface",
                                                 &if_name, VIRSH_BYNAME))) {
        goto cleanup;
    }

    /* Name for new bridge device */
    if (vshCommandOptStringReq(ctl, cmd, "bridge", &br_name) < 0)
        goto cleanup;

    /* make sure "new" device doesn't already exist */
    if ((br_handle = virInterfaceLookupByName(priv->conn, br_name))) {
        vshError(ctl, _("Network device %1$s already exists"), br_name);
        goto cleanup;
    }

    /* use "no-stp" because we want "stp" to default true */
    stp = !vshCommandOptBool(cmd, "no-stp");

    if (vshCommandOptUInt(ctl, cmd, "delay", &delay) < 0)
        goto cleanup;

    nostart = vshCommandOptBool(cmd, "no-start");

    /* Get the original interface into an xmlDoc */
    if (!(if_xml = virInterfaceGetXMLDesc(if_handle, VIR_INTERFACE_XML_INACTIVE)))
        goto cleanup;
    if (!(xml_doc = virXMLParseStringCtxt(if_xml,
                                          _("(interface definition)"), &ctxt))) {
        vshError(ctl, _("Failed to parse configuration of %1$s"), if_name);
        goto cleanup;
    }
    top_node = ctxt->node;

    /* Verify that the original device isn't already a bridge. */
    if (!(if_type = virXMLPropString(top_node, "type"))) {
        vshError(ctl, _("Existing device %1$s has no type"), if_name);
        goto cleanup;
    }

    if (STREQ(if_type, "bridge")) {
        vshError(ctl, _("Existing device %1$s is already a bridge"), if_name);
        goto cleanup;
    }

    /* verify the name in the XML matches the device name */
    if (!(if2_name = virXMLPropString(top_node, "name")) ||
        STRNEQ(if2_name, if_name)) {
        vshError(ctl, _("Interface name from config %1$s doesn't match given supplied name %2$s"),
                 if2_name, if_name);
        goto cleanup;
    }

    /* Create a <bridge> node under <interface>. */
    if (!(br_node = xmlNewChild(top_node, NULL, BAD_CAST "bridge", NULL))) {
        vshError(ctl, "%s", _("Failed to create bridge node in xml document"));
        goto cleanup;
    }

    /* Set stp and delay attributes in <bridge> according to the
     * commandline options.
     */
    if (!xmlSetProp(br_node, BAD_CAST "stp", BAD_CAST(stp ? "on" : "off"))) {
        vshError(ctl, "%s", _("Failed to set stp attribute in xml document"));
        goto cleanup;
    }

    if (stp) {
        delay_str = g_strdup_printf("%d", delay);
        if (!xmlSetProp(br_node, BAD_CAST "delay", BAD_CAST delay_str)) {
            vshError(ctl, _("Failed to set bridge delay %1$d in xml document"), delay);
            goto cleanup;
        }
    }

    /* Change the type of the outer/master interface to "bridge" and the
     * name to the provided bridge name.
     */
    if (!xmlSetProp(top_node, BAD_CAST "type", BAD_CAST "bridge")) {
        vshError(ctl, "%s", _("Failed to set bridge interface type to 'bridge' in xml document"));
        goto cleanup;
    }

    if (!xmlSetProp(top_node, BAD_CAST "name", BAD_CAST br_name)) {
        vshError(ctl, _("Failed to set master bridge interface name to '%1$s' in xml document"),
            br_name);
        goto cleanup;
    }

    /* Create an <interface> node under <bridge> that uses the
     * original interface's type and name.
     */
    if (!(if_node = xmlNewChild(br_node, NULL, BAD_CAST "interface", NULL))) {
        vshError(ctl, "%s", _("Failed to create interface node under bridge node in xml document"));
        goto cleanup;
    }

    /* set the type of the attached interface to the original
     * if_type, and the name to the original if_name.
     */
    if (!xmlSetProp(if_node, BAD_CAST "type", BAD_CAST if_type)) {
        vshError(ctl, _("Failed to set new attached interface type to '%1$s' in xml document"),
                 if_type);
        goto cleanup;
    }

    if (!xmlSetProp(if_node, BAD_CAST "name", BAD_CAST if_name)) {
        vshError(ctl, _("Failed to set new attached interface name to '%1$s' in xml document"),
                 if_name);
        goto cleanup;
    }

    /* Cycle through all the nodes under the original <interface>,
     * moving all <mac>, <bond> and <vlan> nodes down into the new
     * lower level <interface>.
     */
    cur = top_node->children;
    while (cur) {
        xmlNodePtr old = cur;

        cur = cur->next;
        if ((old->type == XML_ELEMENT_NODE) &&
            (virXMLNodeNameEqual(old, "mac") ||  /* ethernet stuff to move down */
             virXMLNodeNameEqual(old, "bond") || /* bond stuff to move down */
             virXMLNodeNameEqual(old, "vlan"))) { /* vlan stuff to move down */
            xmlUnlinkNode(old);
            if (!xmlAddChild(if_node, old)) {
                vshError(ctl, _("Failed to move '%1$s' element in xml document"), old->name);
                xmlFreeNode(old);
                goto cleanup;
            }
        }
    }

    /* The document should now be fully converted; write it out to a string. */
    xmlDocDumpMemory(xml_doc, &br_xml, &br_xml_size);

    if (!br_xml || br_xml_size <= 0) {
        vshError(ctl, _("Failed to format new xml document for bridge %1$s"), br_name);
        goto cleanup;
    }


    /* br_xml is the new interface to define. It will automatically undefine the
     * independent original interface.
     */
    if (!(br_handle = virInterfaceDefineXML(priv->conn, (char *) br_xml, 0))) {
        vshError(ctl, _("Failed to define new bridge interface %1$s"),
                 br_name);
        goto cleanup;
    }

    vshPrintExtra(ctl, _("Created bridge %1$s with attached device %2$s\n"),
                  br_name, if_name);

    /* start it up unless requested not to */
    if (!nostart) {
        if (virInterfaceCreate(br_handle, 0) < 0) {
            vshError(ctl, _("Failed to start bridge interface %1$s"), br_name);
            goto cleanup;
        }
        vshPrintExtra(ctl, _("Bridge interface %1$s started\n"), br_name);
    }

    ret = true;
 cleanup:
    VIR_FREE(if_xml);
    VIR_FREE(br_xml);
    VIR_FREE(if_type);
    VIR_FREE(if2_name);
    VIR_FREE(delay_str);
    return ret;
}

/*
 * "iface-unbridge" command
 */
static const vshCmdInfo info_interface_unbridge = {
    .help = N_("undefine a bridge device after detaching its device(s)"),
    .desc = N_("unbridge a network device"),
};

static const vshCmdOptDef opts_interface_unbridge[] = {
    {.name = "bridge",
     .type = VSH_OT_DATA,
     .positional = true,
     .required = true,
     .flags = VSH_OFLAG_REQ,
     .help = N_("current bridge device name")
    },
    {.name = "no-start",
     .type = VSH_OT_BOOL,
     .help = N_("don't start the detached interface immediately (not recommended)")
    },
    {.name = NULL}
};

static bool
cmdInterfaceUnbridge(vshControl *ctl, const vshCmd *cmd)
{
    bool ret = false;
    g_autoptr(virshInterface) if_handle = NULL;
    g_autoptr(virshInterface) br_handle = NULL;
    const char *br_name;
    char *if_type = NULL, *if_name = NULL;
    bool nostart = false;
    char *br_xml = NULL;
    xmlChar *if_xml = NULL;
    int if_xml_size;
    g_autoptr(xmlDoc) xml_doc = NULL;
    g_autoptr(xmlXPathContext) ctxt = NULL;
    xmlNodePtr top_node, if_node, cur;
    virshControl *priv = ctl->privData;

    /* Get a handle to the original device */
    if (!(br_handle = virshCommandOptInterfaceBy(ctl, cmd, "bridge",
                                                 &br_name, VIRSH_BYNAME))) {
        goto cleanup;
    }

    nostart = vshCommandOptBool(cmd, "no-start");

    /* Get the bridge xml into an xmlDoc */
    if (!(br_xml = virInterfaceGetXMLDesc(br_handle, VIR_INTERFACE_XML_INACTIVE)))
        goto cleanup;
    if (!(xml_doc = virXMLParseStringCtxt(br_xml,
                                          _("(bridge interface definition)"),
                                          &ctxt))) {
        vshError(ctl, _("Failed to parse configuration of %1$s"), br_name);
        goto cleanup;
    }
    top_node = ctxt->node;

    /* Verify that the device really is a bridge. */
    if (!(if_type = virXMLPropString(top_node, "type"))) {
        vshError(ctl, _("Existing device %1$s has no type"), br_name);
        goto cleanup;
    }

    if (STRNEQ(if_type, "bridge")) {
        vshError(ctl, _("Device %1$s is not a bridge"), br_name);
        goto cleanup;
    }
    VIR_FREE(if_type);

    /* verify the name in the XML matches the device name */
    if (!(if_name = virXMLPropString(top_node, "name")) ||
        STRNEQ(if_name, br_name)) {
        vshError(ctl, _("Interface name from config %1$s doesn't match given supplied name %2$s"),
                 if_name, br_name);
        goto cleanup;
    }
    VIR_FREE(if_name);

    /* Find the <bridge> node under <interface>. */
    if (virXPathNode("./bridge", ctxt) == NULL) {
        vshError(ctl, "%s", _("No bridge node in xml document"));
        goto cleanup;
    }

    if (virXPathNode("./bridge/interface[2]", ctxt) != NULL) {
        vshError(ctl, "%s", _("Multiple interfaces attached to bridge"));
        goto cleanup;
    }

    if (!(if_node = virXPathNode("./bridge/interface", ctxt))) {
        vshError(ctl, "%s", _("No interface attached to bridge"));
        goto cleanup;
    }

    /* Change the type and name of the bridge interface to
     * the type/name of the attached interface.
     */
    if (!(if_name = virXMLPropString(if_node, "name"))) {
        vshError(ctl, _("Device attached to bridge %1$s has no name"), br_name);
        goto cleanup;
    }

    if (!(if_type = virXMLPropString(if_node, "type"))) {
        vshError(ctl, _("Attached device %1$s has no type"), if_name);
        goto cleanup;
    }

    if (!xmlSetProp(top_node, BAD_CAST "type", BAD_CAST if_type)) {
        vshError(ctl, _("Failed to set interface type to '%1$s' in xml document"),
                 if_type);
        goto cleanup;
    }

    if (!xmlSetProp(top_node, BAD_CAST "name", BAD_CAST if_name)) {
        vshError(ctl, _("Failed to set interface name to '%1$s' in xml document"),
                 if_name);
        goto cleanup;
    }

    /* Cycle through all the nodes under the attached <interface>,
     * moving all <mac>, <bond> and <vlan> nodes up into the toplevel
     * <interface>.
     */
    cur = if_node->children;
    while (cur) {
        xmlNodePtr old = cur;

        cur = cur->next;
        if ((old->type == XML_ELEMENT_NODE) &&
            (virXMLNodeNameEqual(old, "mac") ||  /* ethernet stuff to move down */
             virXMLNodeNameEqual(old, "bond") || /* bond stuff to move down */
             virXMLNodeNameEqual(old, "vlan"))) { /* vlan stuff to move down */
            xmlUnlinkNode(old);
            if (!xmlAddChild(top_node, old)) {
                vshError(ctl, _("Failed to move '%1$s' element in xml document"), old->name);
                xmlFreeNode(old);
                goto cleanup;
            }
        }
    }

    /* The document should now be fully converted; write it out to a string. */
    xmlDocDumpMemory(xml_doc, &if_xml, &if_xml_size);

    if (!if_xml || if_xml_size <= 0) {
        vshError(ctl, _("Failed to format new xml document for detached interface %1$s"),
                 if_name);
        goto cleanup;
    }

    /* Destroy and Undefine the bridge device, since we otherwise
     * can't safely define the unattached device.
     */
    if (virInterfaceDestroy(br_handle, 0) < 0) {
        vshError(ctl, _("Failed to destroy bridge interface %1$s"), br_name);
        goto cleanup;
    }
    if (virInterfaceUndefine(br_handle) < 0) {
        vshError(ctl, _("Failed to undefine bridge interface %1$s"), br_name);
        goto cleanup;
    }

    /* if_xml is the new interface to define.
     */
    if (!(if_handle = virInterfaceDefineXML(priv->conn, (char *) if_xml, 0))) {
        vshError(ctl, _("Failed to define new interface %1$s"), if_name);
        goto cleanup;
    }

    vshPrintExtra(ctl, _("Device %1$s un-attached from bridge %2$s\n"),
                  if_name, br_name);

    /* unless requested otherwise, undefine the bridge device */
    if (!nostart) {
        if (virInterfaceCreate(if_handle, 0) < 0) {
            vshError(ctl, _("Failed to start interface %1$s"), if_name);
            goto cleanup;
        }
        vshPrintExtra(ctl, _("Interface %1$s started\n"), if_name);
    }

    ret = true;
 cleanup:
    VIR_FREE(if_xml);
    VIR_FREE(br_xml);
    VIR_FREE(if_type);
    VIR_FREE(if_name);
    return ret;
}

const vshCmdDef ifaceCmds[] = {
    {.name = "iface-begin",
     .handler = cmdInterfaceBegin,
     .opts = opts_interface_begin,
     .info = &info_interface_begin,
     .flags = 0
    },
    {.name = "iface-bridge",
     .handler = cmdInterfaceBridge,
     .opts = opts_interface_bridge,
     .info = &info_interface_bridge,
     .flags = 0
    },
    {.name = "iface-commit",
     .handler = cmdInterfaceCommit,
     .opts = opts_interface_commit,
     .info = &info_interface_commit,
     .flags = 0
    },
    {.name = "iface-define",
     .handler = cmdInterfaceDefine,
     .opts = opts_interface_define,
     .info = &info_interface_define,
     .flags = 0
    },
    {.name = "iface-destroy",
     .handler = cmdInterfaceDestroy,
     .opts = opts_interface_destroy,
     .info = &info_interface_destroy,
     .flags = 0
    },
    {.name = "iface-dumpxml",
     .handler = cmdInterfaceDumpXML,
     .opts = opts_interface_dumpxml,
     .info = &info_interface_dumpxml,
     .flags = 0
    },
    {.name = "iface-edit",
     .handler = cmdInterfaceEdit,
     .opts = opts_interface_edit,
     .info = &info_interface_edit,
     .flags = 0
    },
    {.name = "iface-list",
     .handler = cmdInterfaceList,
     .opts = opts_interface_list,
     .info = &info_interface_list,
     .flags = 0
    },
    {.name = "iface-mac",
     .handler = cmdInterfaceMAC,
     .opts = opts_interface_mac,
     .info = &info_interface_mac,
     .flags = 0
    },
    {.name = "iface-name",
     .handler = cmdInterfaceName,
     .opts = opts_interface_name,
     .info = &info_interface_name,
     .flags = 0
    },
    {.name = "iface-rollback",
     .handler = cmdInterfaceRollback,
     .opts = opts_interface_rollback,
     .info = &info_interface_rollback,
     .flags = 0
    },
    {.name = "iface-start",
     .handler = cmdInterfaceStart,
     .opts = opts_interface_start,
     .info = &info_interface_start,
     .flags = 0
    },
    {.name = "iface-unbridge",
     .handler = cmdInterfaceUnbridge,
     .opts = opts_interface_unbridge,
     .info = &info_interface_unbridge,
     .flags = 0
    },
    {.name = "iface-undefine",
     .handler = cmdInterfaceUndefine,
     .opts = opts_interface_undefine,
     .info = &info_interface_undefine,
     .flags = 0
    },
    {.name = NULL}
};