Exemplo n.º 1
0
def block_detach_all(vm, vm_xid = None):
    """ Detach all non-system devices"""
    # Get XID if not provided already
    if vm_xid is None:
        if not vm.is_running():
            raise QubesException("VM %s not running" % vm.name)
        # FIXME: potential race
        vm_xid = vm.xid

    xs_trans = xs.transaction_start()
    devices = xs.ls(xs_trans, '/local/domain/%d/device/vbd' % vm_xid)
    if devices is None:
        return
    devices_to_detach = []
    for devid in devices:
        # check if this is system disk
        be_path = xs.read(xs_trans, '/local/domain/%d/device/vbd/%s/backend' % (vm_xid, devid))
        assert be_path is not None
        be_params = xs.read(xs_trans, be_path + '/params')
        if be_path.startswith('/local/domain/0/') and be_params is not None and be_params.startswith(qubes_base_dir):
            # system disk
            continue
        devices_to_detach.append(devid)
    xs.transaction_end(xs_trans)
    for devid in devices_to_detach:
        xl_cmd = [ '/usr/sbin/xl', 'block-detach', str(vm_xid), devid]
        subprocess.check_call(xl_cmd)
Exemplo n.º 2
0
def block_list(vm = None, system_disks = False):
    device_re = re.compile(r"^[a-z0-9]{1,12}$")
    # FIXME: any better idea of desc_re?
    desc_re = re.compile(r"^.{1,255}$")
    mode_re = re.compile(r"^[rw]$")

    vm_list = []
    if vm is not None:
        if not vm.is_running():
            return []
        else:
            vm_list = [ str(vm.xid) ]
    else:
         vm_list = xs.ls('', '/local/domain')

    xs_trans = xs.transaction_start()
    devices_list = {}
    for xid in vm_list:
        vm_name = xs.read(xs_trans, '/local/domain/%s/name' % xid)
        vm_devices = xs.ls(xs_trans, '/local/domain/%s/qubes-block-devices' % xid)
        if vm_devices is None:
            continue
        for device in vm_devices:
            # Sanitize device name
            if not device_re.match(device):
                print >> sys.stderr, "Invalid device name in VM '%s'" % vm_name
                continue

            device_size = xs.read(xs_trans, '/local/domain/%s/qubes-block-devices/%s/size' % (xid, device))
            device_desc = xs.read(xs_trans, '/local/domain/%s/qubes-block-devices/%s/desc' % (xid, device))
            device_mode = xs.read(xs_trans, '/local/domain/%s/qubes-block-devices/%s/mode' % (xid, device))

            if device_size is None or device_desc is None or device_mode is None:
                print >> sys.stderr, "Missing field in %s device parameters" % device
                continue
            if not device_size.isdigit():
                print >> sys.stderr, "Invalid %s device size in VM '%s'" % (device, vm_name)
                continue
            if not desc_re.match(device_desc):
                print >> sys.stderr, "Invalid %s device desc in VM '%s'" % (device, vm_name)
                continue
            if not mode_re.match(device_mode):
                print >> sys.stderr, "Invalid %s device mode in VM '%s'" % (device, vm_name)
                continue
            # Check if we know major number for this device; attach will work without this, but detach and check_attached don't
            if block_name_to_majorminor(device) == (0, 0):
                print >> sys.stderr, "Unsupported device %s:%s" % (vm_name, device)
                continue

            if not system_disks:
                if xid == '0' and device_desc.startswith(qubes_base_dir):
                    continue

            visible_name = "%s:%s" % (vm_name, device)
            devices_list[visible_name] = {"name": visible_name, "xid":int(xid),
                "vm": vm_name, "device":device, "size":int(device_size),
                "desc":device_desc, "mode":device_mode}

    xs.transaction_end(xs_trans)
    return devices_list
Exemplo n.º 3
0
def block_check_attached(backend_vm, device, backend_xid = None):
    if backend_xid is None:
        backend_xid = backend_vm.xid
    xs_trans = xs.transaction_start()
    vm_list = xs.ls(xs_trans, '/local/domain/%d/backend/vbd' % backend_xid)
    if vm_list is None:
        xs.transaction_end(xs_trans)
        return None
    device_majorminor = None
    try:
        device_majorminor = block_name_to_majorminor(device)
    except:
        # Unknown devices will be compared directly - perhaps it is a filename?
        pass
    for vm_xid in vm_list:
        for devid in xs.ls(xs_trans, '/local/domain/%d/backend/vbd/%s' % (backend_xid, vm_xid)):
            (tmp_major, tmp_minor) = (0, 0)
            phys_device = xs.read(xs_trans, '/local/domain/%d/backend/vbd/%s/%s/physical-device' % (backend_xid, vm_xid, devid))
            dev_params = xs.read(xs_trans, '/local/domain/%d/backend/vbd/%s/%s/params' % (backend_xid, vm_xid, devid))
            if phys_device and phys_device.find(':'):
                (tmp_major, tmp_minor) = phys_device.split(":")
                tmp_major = int(tmp_major, 16)
                tmp_minor = int(tmp_minor, 16)
            else:
                # perhaps not ready yet - check params
                if not dev_params:
                    # Skip not-phy devices
                    continue
                elif not dev_params.startswith('/dev/'):
                    # will compare params directly
                    pass
                else:
                    (tmp_major, tmp_minor) = block_name_to_majorminor(dev_params.lstrip('/dev/'))

            if (device_majorminor and (tmp_major, tmp_minor) == device_majorminor) or \
               (device_majorminor is None and dev_params == device):
                vm_name = xl_ctx.domid_to_name(int(vm_xid))
                frontend = block_devid_to_name(int(devid))
                xs.transaction_end(xs_trans)
                return {"xid":int(vm_xid), "frontend": frontend, "devid": int(devid), "vm": vm_name}
    xs.transaction_end(xs_trans)
    return None
Exemplo n.º 4
0
def block_detach(vm, frontend = "xvdi", vm_xid = None):
    # Get XID if not provided already
    if vm_xid is None:
        if not vm.is_running():
            raise QubesException("VM %s not running" % vm.name)
        # FIXME: potential race
        vm_xid = vm.xid

    # Check if this device is really connected
    if not xs.read('', '/local/domain/%d/device/vbd/%d/state' % (vm_xid, block_name_to_devid(frontend))) == '4':
        # Do nothing - device already detached
        return

    xl_cmd = [ '/usr/sbin/xl', 'block-detach', str(vm_xid), str(frontend)]
    subprocess.check_call(xl_cmd)
Exemplo n.º 5
0
def block_attach(vm, backend_vm, device, frontend=None, mode="w", auto_detach=False, wait=True):
    if not vm.is_running():
        raise QubesException("VM %s not running" % vm.name)

    if not backend_vm.is_running():
        raise QubesException("VM %s not running" % backend_vm.name)

    if frontend is None:
        frontend = block_find_unused_frontend(vm)
        if frontend is None:
            raise QubesException("No unused frontend found")
    else:
        # Check if any device attached at this frontend
        if xs.read('', '/local/domain/%d/device/vbd/%d/state' % (vm.xid, block_name_to_devid(frontend))) == '4':
            raise QubesException("Frontend %s busy in VM %s, detach it first" % (frontend, vm.name))

    # Check if this device is attached to some domain
    attached_vm = block_check_attached(backend_vm, device)
    if attached_vm:
        if auto_detach:
            block_detach(None, attached_vm['devid'], vm_xid=attached_vm['xid'])
        else:
            raise QubesException("Device %s from %s already connected to VM %s as %s" % (device, backend_vm.name, attached_vm['vm'], attached_vm['frontend']))

    if device.startswith('/'):
        backend_dev = 'script:file:' + device
    else:
        backend_dev = 'phy:/dev/' + device

    xl_cmd = [ '/usr/sbin/xl', 'block-attach', vm.name, backend_dev, frontend, mode, str(backend_vm.xid) ]
    subprocess.check_call(xl_cmd)
    if wait:
        be_path = '/local/domain/%d/backend/vbd/%d/%d' % (backend_vm.xid, vm.xid, block_name_to_devid(frontend))
        # There is no way to use xenstore watch with a timeout, so must check in a loop
        interval = 0.100
        # 5sec timeout
        timeout = 5/interval
        while timeout > 0:
            be_state = xs.read('', be_path + '/state')
            hotplug_state = xs.read('', be_path + '/hotplug-status')
            if be_state is None:
                raise QubesException("Backend device disappeared, something weird happend")
            elif int(be_state) == 4:
                # Ok
                return
            elif int(be_state) > 4:
                # Error
                error = xs.read('', '/local/domain/%d/error/backend/vbd/%d/%d/error' % (backend_vm.xid, vm.xid, block_name_to_devid(frontend)))
                if error is not None:
                    raise QubesException("Error while connecting block device: " + error)
                else:
                    raise QubesException("Unknown error while connecting block device")
            elif hotplug_state == 'error':
                hotplug_error = xs.read('', be_path + '/hotplug-error')
                if hotplug_error:
                    raise QubesException("Error while connecting block device: " + hotplug_error)
                else:
                    raise QubesException("Unknown hotplug error while connecting block device")
            time.sleep(interval)
            timeout -= interval
        raise QubesException("Timeout while waiting for block defice connection")