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-rw-r--r--src/ceph-volume/ceph_volume/util/encryption.py278
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diff --git a/src/ceph-volume/ceph_volume/util/encryption.py b/src/ceph-volume/ceph_volume/util/encryption.py
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+++ b/src/ceph-volume/ceph_volume/util/encryption.py
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+import base64
+import os
+import logging
+from ceph_volume import process, conf, terminal
+from ceph_volume.util import constants, system
+from ceph_volume.util.device import Device
+from .prepare import write_keyring
+from .disk import lsblk, device_family, get_part_entry_type
+
+logger = logging.getLogger(__name__)
+mlogger = terminal.MultiLogger(__name__)
+
+def get_key_size_from_conf():
+ """
+ Return the osd dmcrypt key size from config file.
+ Default is 512.
+ """
+ default_key_size = '512'
+ key_size = conf.ceph.get_safe(
+ 'osd',
+ 'osd_dmcrypt_key_size',
+ default='512', check_valid=False)
+
+ if key_size not in ['256', '512']:
+ logger.warning(("Invalid value set for osd_dmcrypt_key_size ({}). "
+ "Falling back to {}bits".format(key_size, default_key_size)))
+ return default_key_size
+
+ return key_size
+
+def create_dmcrypt_key():
+ """
+ Create the secret dm-crypt key (KEK) used to encrypt/decrypt the Volume Key.
+ """
+ random_string = os.urandom(128)
+ key = base64.b64encode(random_string).decode('utf-8')
+ return key
+
+
+def luks_format(key, device):
+ """
+ Decrypt (open) an encrypted device, previously prepared with cryptsetup
+
+ :param key: dmcrypt secret key, will be used for decrypting
+ :param device: Absolute path to device
+ """
+ command = [
+ 'cryptsetup',
+ '--batch-mode', # do not prompt
+ '--key-size',
+ get_key_size_from_conf(),
+ '--key-file', # misnomer, should be key
+ '-', # because we indicate stdin for the key here
+ 'luksFormat',
+ device,
+ ]
+ process.call(command, stdin=key, terminal_verbose=True, show_command=True)
+
+
+def plain_open(key, device, mapping):
+ """
+ Decrypt (open) an encrypted device, previously prepared with cryptsetup in plain mode
+
+ .. note: ceph-disk will require an additional b64decode call for this to work
+
+ :param key: dmcrypt secret key
+ :param device: absolute path to device
+ :param mapping: mapping name used to correlate device. Usually a UUID
+ """
+ command = [
+ 'cryptsetup',
+ '--key-file',
+ '-',
+ '--allow-discards', # allow discards (aka TRIM) requests for device
+ 'open',
+ device,
+ mapping,
+ '--type', 'plain',
+ '--key-size', '256',
+ ]
+
+ process.call(command, stdin=key, terminal_verbose=True, show_command=True)
+
+
+def luks_open(key, device, mapping):
+ """
+ Decrypt (open) an encrypted device, previously prepared with cryptsetup
+
+ .. note: ceph-disk will require an additional b64decode call for this to work
+
+ :param key: dmcrypt secret key
+ :param device: absolute path to device
+ :param mapping: mapping name used to correlate device. Usually a UUID
+ """
+ command = [
+ 'cryptsetup',
+ '--key-size',
+ get_key_size_from_conf(),
+ '--key-file',
+ '-',
+ '--allow-discards', # allow discards (aka TRIM) requests for device
+ 'luksOpen',
+ device,
+ mapping,
+ ]
+ process.call(command, stdin=key, terminal_verbose=True, show_command=True)
+
+
+def dmcrypt_close(mapping):
+ """
+ Encrypt (close) a device, previously decrypted with cryptsetup
+
+ :param mapping:
+ """
+ if not os.path.exists(mapping):
+ logger.debug('device mapper path does not exist %s' % mapping)
+ logger.debug('will skip cryptsetup removal')
+ return
+ # don't be strict about the remove call, but still warn on the terminal if it fails
+ process.run(['cryptsetup', 'remove', mapping], stop_on_error=False)
+
+
+def get_dmcrypt_key(osd_id, osd_fsid, lockbox_keyring=None):
+ """
+ Retrieve the dmcrypt (secret) key stored initially on the monitor. The key
+ is sent initially with JSON, and the Monitor then mangles the name to
+ ``dm-crypt/osd/<fsid>/luks``
+
+ The ``lockbox.keyring`` file is required for this operation, and it is
+ assumed it will exist on the path for the same OSD that is being activated.
+ To support scanning, it is optionally configurable to a custom location
+ (e.g. inside a lockbox partition mounted in a temporary location)
+ """
+ if lockbox_keyring is None:
+ lockbox_keyring = '/var/lib/ceph/osd/%s-%s/lockbox.keyring' % (conf.cluster, osd_id)
+ name = 'client.osd-lockbox.%s' % osd_fsid
+ config_key = 'dm-crypt/osd/%s/luks' % osd_fsid
+
+ mlogger.info(f'Running ceph config-key get {config_key}')
+ stdout, stderr, returncode = process.call(
+ [
+ 'ceph',
+ '--cluster', conf.cluster,
+ '--name', name,
+ '--keyring', lockbox_keyring,
+ 'config-key',
+ 'get',
+ config_key
+ ],
+ show_command=True,
+ logfile_verbose=False
+ )
+ if returncode != 0:
+ raise RuntimeError('Unable to retrieve dmcrypt secret')
+ return ' '.join(stdout).strip()
+
+
+def write_lockbox_keyring(osd_id, osd_fsid, secret):
+ """
+ Helper to write the lockbox keyring. This is needed because the bluestore OSD will
+ not persist the keyring, and it can't be stored in the data device for filestore because
+ at the time this is needed, the device is encrypted.
+
+ For bluestore: A tmpfs filesystem is mounted, so the path can get written
+ to, but the files are ephemeral, which requires this file to be created
+ every time it is activated.
+ For filestore: The path for the OSD would exist at this point even if no
+ OSD data device is mounted, so the keyring is written to fetch the key, and
+ then the data device is mounted on that directory, making the keyring
+ "disappear".
+ """
+ if os.path.exists('/var/lib/ceph/osd/%s-%s/lockbox.keyring' % (conf.cluster, osd_id)):
+ return
+
+ name = 'client.osd-lockbox.%s' % osd_fsid
+ write_keyring(
+ osd_id,
+ secret,
+ keyring_name='lockbox.keyring',
+ name=name
+ )
+
+
+def status(device):
+ """
+ Capture the metadata information of a possibly encrypted device, returning
+ a dictionary with all the values found (if any).
+
+ An encrypted device will contain information about a device. Example
+ successful output looks like::
+
+ $ cryptsetup status /dev/mapper/ed6b5a26-eafe-4cd4-87e3-422ff61e26c4
+ /dev/mapper/ed6b5a26-eafe-4cd4-87e3-422ff61e26c4 is active and is in use.
+ type: LUKS1
+ cipher: aes-xts-plain64
+ keysize: 256 bits
+ device: /dev/sdc2
+ offset: 4096 sectors
+ size: 20740063 sectors
+ mode: read/write
+
+ As long as the mapper device is in 'open' state, the ``status`` call will work.
+
+ :param device: Absolute path or UUID of the device mapper
+ """
+ command = [
+ 'cryptsetup',
+ 'status',
+ device,
+ ]
+ out, err, code = process.call(command, show_command=True, verbose_on_failure=False)
+
+ metadata = {}
+ if code != 0:
+ logger.warning('failed to detect device mapper information')
+ return metadata
+ for line in out:
+ # get rid of lines that might not be useful to construct the report:
+ if not line.startswith(' '):
+ continue
+ try:
+ column, value = line.split(': ')
+ except ValueError:
+ continue
+ metadata[column.strip()] = value.strip().strip('"')
+ return metadata
+
+
+def legacy_encrypted(device):
+ """
+ Detect if a device was encrypted with ceph-disk or not. In the case of
+ encrypted devices, include the type of encryption (LUKS, or PLAIN), and
+ infer what the lockbox partition is.
+
+ This function assumes that ``device`` will be a partition.
+ """
+ if os.path.isdir(device):
+ mounts = system.Mounts(paths=True).get_mounts()
+ # yes, rebind the device variable here because a directory isn't going
+ # to help with parsing
+ device = mounts.get(device, [None])[0]
+ if not device:
+ raise RuntimeError('unable to determine the device mounted at %s' % device)
+ metadata = {'encrypted': False, 'type': None, 'lockbox': '', 'device': device}
+ # check if the device is online/decrypted first
+ active_mapper = status(device)
+ if active_mapper:
+ # normalize a bit to ensure same values regardless of source
+ metadata['type'] = active_mapper['type'].lower().strip('12') # turn LUKS1 or LUKS2 into luks
+ metadata['encrypted'] = True if metadata['type'] in ['plain', 'luks'] else False
+ # The true device is now available to this function, so it gets
+ # re-assigned here for the lockbox checks to succeed (it is not
+ # possible to guess partitions from a device mapper device otherwise
+ device = active_mapper.get('device', device)
+ metadata['device'] = device
+ else:
+ uuid = get_part_entry_type(device)
+ guid_match = constants.ceph_disk_guids.get(uuid, {})
+ encrypted_guid = guid_match.get('encrypted', False)
+ if encrypted_guid:
+ metadata['encrypted'] = True
+ metadata['type'] = guid_match['encryption_type']
+
+ # Lets find the lockbox location now, to do this, we need to find out the
+ # parent device name for the device so that we can query all of its
+ # associated devices and *then* look for one that has the 'lockbox' label
+ # on it. Thanks for being awesome ceph-disk
+ disk_meta = lsblk(device, abspath=True)
+ if not disk_meta:
+ return metadata
+ parent_device = disk_meta['PKNAME']
+ # With the parent device set, we can now look for the lockbox listing associated devices
+ devices = [Device(i['NAME']) for i in device_family(parent_device)]
+ for d in devices:
+ if d.ceph_disk.type == 'lockbox':
+ metadata['lockbox'] = d.path
+ break
+ return metadata