diff options
Diffstat (limited to 'cloudinit/config')
| -rw-r--r-- | cloudinit/config/cc_grub_dpkg.py | 95 | ||||
| -rw-r--r-- | cloudinit/config/tests/test_grub_dpkg.py | 176 |
2 files changed, 246 insertions, 25 deletions
diff --git a/cloudinit/config/cc_grub_dpkg.py b/cloudinit/config/cc_grub_dpkg.py index a323edfa..7888464e 100644 --- a/cloudinit/config/cc_grub_dpkg.py +++ b/cloudinit/config/cc_grub_dpkg.py @@ -1,8 +1,9 @@ -# Copyright (C) 2009-2010 Canonical Ltd. +# Copyright (C) 2009-2010, 2020 Canonical Ltd. # Copyright (C) 2012 Hewlett-Packard Development Company, L.P. # # Author: Scott Moser <scott.moser@canonical.com> # Author: Juerg Haefliger <juerg.haefliger@hp.com> +# Author: Matthew Ruffell <matthew.ruffell@canonical.com> # # This file is part of cloud-init. See LICENSE file for license information. @@ -15,15 +16,15 @@ Configure which device is used as the target for grub installation. This module should work correctly by default without any user configuration. It can be enabled/disabled using the ``enabled`` config key in the ``grub_dpkg`` config dict. The global config key ``grub-dpkg`` is an alias for ``grub_dpkg``. If no -installation device is specified this module will look for the first existing -device in: +installation device is specified this module will execute grub-probe to +determine which disk the /boot directory is associated with. - - ``/dev/sda`` - - ``/dev/vda`` - - ``/dev/xvda`` - - ``/dev/sda1`` - - ``/dev/vda1`` - - ``/dev/xvda1`` +The value which is placed into the debconf database is in the format which the +grub postinstall script expects. Normally, this is a /dev/disk/by-id/ value, +but we do fallback to the plain disk name if a by-id name is not present. + +If this module is executed inside a container, then the debconf database is +seeded with empty values, and install_devices_empty is set to true. **Internal name:** ``cc_grub_dpkg`` @@ -43,10 +44,66 @@ device in: import os from cloudinit import util +from cloudinit.util import ProcessExecutionError distros = ['ubuntu', 'debian'] +def fetch_idevs(log): + """ + Fetches the /dev/disk/by-id device grub is installed to. + Falls back to plain disk name if no by-id entry is present. + """ + disk = "" + devices = [] + + try: + # get the root disk where the /boot directory resides. + disk = util.subp(['grub-probe', '-t', 'disk', '/boot'], + capture=True)[0].strip() + except ProcessExecutionError as e: + # grub-common may not be installed, especially on containers + # FileNotFoundError is a nested exception of ProcessExecutionError + if isinstance(e.reason, FileNotFoundError): + log.debug("'grub-probe' not found in $PATH") + # disks from the container host are present in /proc and /sys + # which is where grub-probe determines where /boot is. + # it then checks for existence in /dev, which fails as host disks + # are not exposed to the container. + elif "failed to get canonical path" in e.stderr: + log.debug("grub-probe 'failed to get canonical path'") + else: + # something bad has happened, continue to log the error + raise + except Exception: + util.logexc(log, "grub-probe failed to execute for grub-dpkg") + + if not disk or not os.path.exists(disk): + # If we failed to detect a disk, we can return early + return '' + + try: + # check if disk exists and use udevadm to fetch symlinks + devices = util.subp( + ['udevadm', 'info', '--root', '--query=symlink', disk], + capture=True + )[0].strip().split() + except Exception: + util.logexc( + log, "udevadm DEVLINKS symlink query failed for disk='%s'", disk + ) + + log.debug('considering these device symlinks: %s', ','.join(devices)) + # filter symlinks for /dev/disk/by-id entries + devices = [dev for dev in devices if 'disk/by-id' in dev] + log.debug('filtered to these disk/by-id symlinks: %s', ','.join(devices)) + # select first device if there is one, else fall back to plain name + idevs = sorted(devices)[0] if devices else disk + log.debug('selected %s', idevs) + + return idevs + + def handle(name, cfg, _cloud, log, _args): mycfg = cfg.get("grub_dpkg", cfg.get("grub-dpkg", {})) @@ -62,22 +119,10 @@ def handle(name, cfg, _cloud, log, _args): idevs_empty = util.get_cfg_option_str( mycfg, "grub-pc/install_devices_empty", None) - if ((os.path.exists("/dev/sda1") and not os.path.exists("/dev/sda")) or - (os.path.exists("/dev/xvda1") and not os.path.exists("/dev/xvda"))): - if idevs is None: - idevs = "" - if idevs_empty is None: - idevs_empty = "true" - else: - if idevs_empty is None: - idevs_empty = "false" - if idevs is None: - idevs = "/dev/sda" - for dev in ("/dev/sda", "/dev/vda", "/dev/xvda", - "/dev/sda1", "/dev/vda1", "/dev/xvda1"): - if os.path.exists(dev): - idevs = dev - break + if idevs is None: + idevs = fetch_idevs(log) + if idevs_empty is None: + idevs_empty = "false" if idevs else "true" # now idevs and idevs_empty are set to determined values # or, those set by user diff --git a/cloudinit/config/tests/test_grub_dpkg.py b/cloudinit/config/tests/test_grub_dpkg.py new file mode 100644 index 00000000..01efa330 --- /dev/null +++ b/cloudinit/config/tests/test_grub_dpkg.py @@ -0,0 +1,176 @@ +# This file is part of cloud-init. See LICENSE file for license information. + +import pytest + +from unittest import mock +from logging import Logger +from cloudinit.util import ProcessExecutionError +from cloudinit.config.cc_grub_dpkg import fetch_idevs, handle + + +class TestFetchIdevs: + """Tests cc_grub_dpkg.fetch_idevs()""" + + # Note: udevadm info returns devices in a large single line string + @pytest.mark.parametrize( + "grub_output,path_exists,expected_log_call,udevadm_output" + ",expected_idevs", + [ + # Inside a container, grub not installed + ( + ProcessExecutionError(reason=FileNotFoundError()), + False, + mock.call("'grub-probe' not found in $PATH"), + '', + '', + ), + # Inside a container, grub installed + ( + ProcessExecutionError(stderr="failed to get canonical path"), + False, + mock.call("grub-probe 'failed to get canonical path'"), + '', + '', + ), + # KVM Instance + ( + ['/dev/vda'], + True, + None, + ( + '/dev/disk/by-path/pci-0000:00:00.0 ', + '/dev/disk/by-path/virtio-pci-0000:00:00.0 ' + ), + '/dev/vda', + ), + # Xen Instance + ( + ['/dev/xvda'], + True, + None, + '', + '/dev/xvda', + ), + # NVMe Hardware Instance + ( + ['/dev/nvme1n1'], + True, + None, + ( + '/dev/disk/by-id/nvme-Company_hash000 ', + '/dev/disk/by-id/nvme-nvme.000-000-000-000-000 ', + '/dev/disk/by-path/pci-0000:00:00.0-nvme-0 ' + ), + '/dev/disk/by-id/nvme-Company_hash000', + ), + # SCSI Hardware Instance + ( + ['/dev/sda'], + True, + None, + ( + '/dev/disk/by-id/company-user-1 ', + '/dev/disk/by-id/scsi-0Company_user-1 ', + '/dev/disk/by-path/pci-0000:00:00.0-scsi-0:0:0:0 ' + ), + '/dev/disk/by-id/company-user-1', + ), + ], + ) + @mock.patch("cloudinit.config.cc_grub_dpkg.util.logexc") + @mock.patch("cloudinit.config.cc_grub_dpkg.os.path.exists") + @mock.patch("cloudinit.config.cc_grub_dpkg.util.subp") + def test_fetch_idevs(self, m_subp, m_exists, m_logexc, grub_output, + path_exists, expected_log_call, udevadm_output, + expected_idevs): + """Tests outputs from grub-probe and udevadm info against grub-dpkg""" + m_subp.side_effect = [ + grub_output, + ["".join(udevadm_output)] + ] + m_exists.return_value = path_exists + log = mock.Mock(spec=Logger) + idevs = fetch_idevs(log) + assert expected_idevs == idevs + if expected_log_call is not None: + assert expected_log_call in log.debug.call_args_list + + +class TestHandle: + """Tests cc_grub_dpkg.handle()""" + + @pytest.mark.parametrize( + "cfg_idevs,cfg_idevs_empty,fetch_idevs_output,expected_log_output", + [ + ( + # No configuration + None, + None, + '/dev/disk/by-id/nvme-Company_hash000', + ( + "Setting grub debconf-set-selections with ", + "'/dev/disk/by-id/nvme-Company_hash000','false'" + ), + ), + ( + # idevs set, idevs_empty unset + '/dev/sda', + None, + '/dev/sda', + ( + "Setting grub debconf-set-selections with ", + "'/dev/sda','false'" + ), + ), + ( + # idevs unset, idevs_empty set + None, + 'true', + '/dev/xvda', + ( + "Setting grub debconf-set-selections with ", + "'/dev/xvda','true'" + ), + ), + ( + # idevs set, idevs_empty set + '/dev/vda', + 'false', + '/dev/disk/by-id/company-user-1', + ( + "Setting grub debconf-set-selections with ", + "'/dev/vda','false'" + ), + ), + ( + # idevs set, idevs_empty set + # Respect what the user defines, even if its logically wrong + '/dev/nvme0n1', + 'true', + '', + ( + "Setting grub debconf-set-selections with ", + "'/dev/nvme0n1','true'" + ), + ) + ], + ) + @mock.patch("cloudinit.config.cc_grub_dpkg.fetch_idevs") + @mock.patch("cloudinit.config.cc_grub_dpkg.util.get_cfg_option_str") + @mock.patch("cloudinit.config.cc_grub_dpkg.util.logexc") + @mock.patch("cloudinit.config.cc_grub_dpkg.util.subp") + def test_handle(self, m_subp, m_logexc, m_get_cfg_str, m_fetch_idevs, + cfg_idevs, cfg_idevs_empty, fetch_idevs_output, + expected_log_output): + """Test setting of correct debconf database entries""" + m_get_cfg_str.side_effect = [ + cfg_idevs, + cfg_idevs_empty + ] + m_fetch_idevs.return_value = fetch_idevs_output + log = mock.Mock(spec=Logger) + handle(mock.Mock(), mock.Mock(), mock.Mock(), log, mock.Mock()) + log.debug.assert_called_with("".join(expected_log_output)) + + +# vi: ts=4 expandtab |