Bug 996457

Some background how OpenLMI uses LUKS / Blivet:

We want to be able separately control creation of LUKSFormat and opening it as LUKSDevice.

I.e. remote application scans a system and finds empty partition. The application then creates LUKSFormat there, *without opening it*.

As second step, (potentially different) remote application scans the same system and finds a LUKSFormat there and decides to *open* it - that's why we need working LUKSDevice() constructor and ActionCreateDevice. The same application might close the LUKSDevice later (ActionDestroyDevice with LUKSDevice), while leaving the LUKSFormat there to be opened again later.

(and that's why we need blivet.reset() not to open any LUKS formats it finds, see bug #996118 - reset() should just scan the system, without modifying it).

(In reply to Jan Safranek from comment #1)
> need working LUKSDevice() constructor and ActionCreateDevice. The same
> application might close the LUKSDevice later (ActionDestroyDevice with
> LUKSDevice), while leaving the LUKSFormat there to be opened again later.

If you want to close a device, use device.teardown -- not device.destroy. StorageDevice.destroy permanently _destroys_ the device.

Basically, there will always be a LUKSDevice associated with a device that contains a LUKS format. Whether or not that LUKS format can be opened is a different matter (decided by presence of a valid key/passphrase).

From your reproducer:

luksdevice = blivet.devices.LUKSDevice('luks-test-blivet',
                                       size=d.size,
                                       uuid=d.format.uuid,
                                       sysfsPath=d.sysfsPath,
                                       format=d.format, # <-- here's your problem
                                       parents=[d],
                                       exists=False)

Two devices cannot share the same DeviceFormat instance. Every block device contains its own DeviceFormat instance. The device that is formatted as luks has a LUKS instance as its format. The open/mapped device that represents the decrypted/usable luks device (eg: /dev/mapper/luks-whatever) has a format that represents what is on the decrypted device, such as an ext4 filesystem. Does this clarify things?

Does it mean that I have to know what filesystem there is underneath the luks layer and prepare the format accordingly? That doesn't sound right to me. I'm still confused about what to put into the format parameter.

You don't have to pass a format at all if you don't know what you'll be formatting it as or if you plan to leave it unformatted for the time being.

Ok, the following seems to work:

import blivet

b = blivet.Blivet()
b.reset()
d = b.devicetree.getDeviceByPath('/dev/vda12')
d.format.passphrase = 'fiembi43mygf'
d.format.mapName = 'luks-test-blivet'
luksdevice = blivet.devices.LUKSDevice('luks-test-blivet',
                                       uuid=d.format.uuid,
                                       parents=[d])

action = blivet.ActionCreateDevice(luksdevice)
action.execute()

Is it supposed to work like that? I mean the part where I'm setting passphrase and mapName in the *original* format.

(In reply to Jan Synacek from comment #6)
> Is it supposed to work like that? I mean the part where I'm setting
> passphrase and mapName in the *original* format.

Normally you would create a new luks format if you want to create a new luks device:

# no need to set map name as it will get updated automatically
fmt = blivet.formats.getFormat("luks", passphrase="blahblahblah")
b.formatDevice(d, fmt)

luksdevice = blivet.devices.LUKSDevice('luks-whatever',
                                       parents=[d])
b.createDevice(luksdevice)

b.doIt() # or b.devicetree.processActions()

import blivet

b = blivet.Blivet()
b.reset()
d = b.devicetree.getDeviceByPath('/dev/vda12')

fmt = blivet.formats.getFormat("luks", passphrase='fiembi43mygf')
b.formatDevice(d, fmt)
luksdevice = blivet.devices.LUKSDevice('luks-test-blivet',
                                       parents=[d])

b.createDevice(luksdevice)
b.doIt()

This works, except that the LUKS device is opened as luks-<uuid>, not 'luks-test-blivet'. It seems that the first argument of LUKSDevice() gets somehow ignored. I even tried to set map name whereever it was possible, still ignored.

(In reply to Jan Synacek from comment #8)
> This works, except that the LUKS device is opened as luks-<uuid>, not
> 'luks-test-blivet'. It seems that the first argument of LUKSDevice() gets
> somehow ignored. I even tried to set map name whereever it was possible,
> still ignored.

Right -- this is a relic from anaconda usage. I need to make the automatic transition to luks-$UUID for the map name installer-only behavior.

python-blivet-0.21-1.fc20 has been submitted as an update for Fedora 20.
https://admin.fedoraproject.org/updates/python-blivet-0.21-1.fc20

Package python-blivet-0.21-1.fc20:
* should fix your issue,
* was pushed to the Fedora 20 testing repository,
* should be available at your local mirror within two days.
Update it with:
# su -c 'yum update --enablerepo=updates-testing python-blivet-0.21-1.fc20'
as soon as you are able to.
Please go to the following url:
https://admin.fedoraproject.org/updates/FEDORA-2013-15976/python-blivet-0.21-1.fc20
then log in and leave karma (feedback).

python-blivet-0.22-1.fc20 has been submitted as an update for Fedora 20.
https://admin.fedoraproject.org/updates/python-blivet-0.22-1.fc20

Traceback (most recent call last):
  File "blivet-luks-bug2-bz.py", line 13, in <module>
    b.doIt()
  File "/usr/lib/python2.7/site-packages/blivet/__init__.py", line 310, in doIt
    self.devicetree.processActions()
  File "/usr/lib/python2.7/site-packages/blivet/devicetree.py", line 237, in processActions
    action.execute()
  File "/usr/lib/python2.7/site-packages/blivet/deviceaction.py", line 272, in execute
    self.device.create()
  File "/usr/lib/python2.7/site-packages/blivet/devices.py", line 786, in create
    self._preCreate()
  File "/usr/lib/python2.7/site-packages/blivet/devices.py", line 777, in _preCreate
    self.setupParents()
  File "/usr/lib/python2.7/site-packages/blivet/devices.py", line 841, in setupParents
    _format.setup()
  File "/usr/lib/python2.7/site-packages/blivet/formats/luks.py", line 164, in setup
    raise LUKSError("luks device not configured")
blivet.errors.LUKSError: luks device not configured

I'm getting this with the same code snipped as in comment 8.

# rpm -q python-blivet
python-blivet-0.22-1.fc21.noarch

This bug appears to have been reported against 'rawhide' during the Fedora 20 development cycle.
Changing version to '20'.

More information and reason for this action is here:
https://fedoraproject.org/wiki/BugZappers/HouseKeeping/Fedora20

python-blivet-0.22-1.fc20 has been pushed to the Fedora 20 stable repository.  If problems still persist, please make note of it in this bug report.

I'm still able to reproduce the crash reported in comment #13 using python-blivet-0.23-1.fc21.noarch.

blivet creates the LUKS on the right device, but fails shortly after that, still in devicetree.processActions().

(In reply to Jan Synacek from comment #8)
> fmt = blivet.formats.getFormat("luks", passphrase='fiembi43mygf')
> b.formatDevice(d, fmt)
> luksdevice = blivet.devices.LUKSDevice('luks-test-blivet',
>                                        parents=[d])

You should pass the name to the LUKS constructor as well as the LUKSDevice constructor. Your getFormat call should look like this:

fmt = blivet.formats.getFormat("luks",
                               passphrase='fiembi43mygf',
                               name='luks-test-blivet')