Switch to os-brick encryptor provider implementations

[Lee Yarwood]

Description
===========
Nova and os-brick both currently provide encryptor implementations after these were copied into os-brick by the following change :

Copy encryptors from Nova to os-brick
https://review.openstack.org/#/c/247372/

As these are now at risk of becoming out of sync with Nova due to bug#1639221, bug#1633518 & bug#1639293 we should really re-sync everything with os-brick and remove the implementations from Nova.

Steps to reproduce
==================
Attach an encrypted volume to an instance.

Expected result
===============
encryptor implementations supplied by os-brick.

Actual result
=============
encryptor implementations supplied by Nova.

Environment
===========
1. Exact version of OpenStack you are running. See the following
   Ocata master

2. Which hypervisor did you use?
   libvirt appears to be the only virt-driver using these implementations at present.

2. Which storage type did you use?
   N/A

3. Which networking type did you use?
   N/A

Logs & Configs
==============
N/A

[Lee Yarwood (lyarwood)]

Documenting the additional fixes that have landed in os-brick since the original copy. Note that the original copy itself refactored a few things so re-syncing is going to be FUN!

# cd os-brick
# git rev-parse HEAD
fb0b7e3e3ef32d46a5c4dbc2604d008b80864d8a
# git log os_brick/encryptors/
commit 9daa20e78e0a3bb0c285911a8e098f7e47c718c8
Author: lisali <email address hidden>
Date: Tue Aug 16 15:37:35 2016 +0800

    Add missing %s in print message

    This is to add some missing %s in print message.

    Change-Id: I7ac9b9ee8874d946f2e70cc9d5ad4cdc214e2e18

commit 14df0c7721d0a8a8433a3a7aa6a53372a60efdfe
Author: yuyafei <email address hidden>
Date: Sat Jul 9 10:17:48 2016 +0800

    Remove unused LOG to keep code clean

    TrivialFix

    Change-Id: I2dde2430011a777bffc1f0d25886784c9ed04b68

commit 9d2bb5e15de92c72cc50bac2ee5d0b3b2704ed1e
Author: lisali <email address hidden>
Date: Wed Jul 6 13:48:20 2016 +0800

    Fix multipath iSCSI encrypted volume attach failure

    This is to copy fix of bug 1439869 from Nova to os-brick.

    Currently iSCSI volume attachment fails if iscsi_use_multipath is
    set to True. This is because the encryptor requests cryptsetup
    to create the symlink to the LUKS device with the same name of
    the device-mapper multipath device. To avoid the name collision,
    this patch adds the 'crypt-' prefix to the symlink.

    Change-Id: Ia001204df9b14f635ab998590e8add119c1aec23
    Closes-Bug: #1439869

commit 05827810ca931dafafd19fa4e95143fbede1a3dc
Author: LisaLi <email address hidden>
Date: Thu Nov 19 08:55:36 2015 +0000

    Copy encryptors from Nova to os-brick

    Currently, when creating an encrypted volume from an image, Cinder
    writes raw data to the encrypted volume. When Cinder uploads an
    encrypted volume to an image, it writes encrypted data to the image.
    As a result, Nova cannot use these images or volumes.
    To fix above problem, cinder needs to add encryptor attach/detach
    layers.
    As both Nova and Cinder needs to use the module, the fix is to
    move it to os-brick.
    It copies encryptors from Nova to os-brick, and keep all interfaces
    unchanged except initialization.

    Change-Id: I8044183ad02110c8b2468e20327d822c0437c772
    Implements: blueprint improve-encrypted-volume
    Related-bug: #1482464
    Related-bug: #1465656

[Sean McGinnis (sean-mcginnis)]

Does this actually impact os-brick? My understanding is everything is there and nova just needs to be updated to use it.

[Sean Dague (sdague)]

There are no currently open reviews on this bug, changing
the status back to the previous state and unassigning. If
there are active reviews related to this bug, please include
links in comments.

[Sean Dague (sdague)]

Automatically discovered version ocata in description. If this is incorrect, please update the description to include 'nova version: ...'

[Matt Riedemann (mriedem)]

Yes this was all done here: https://review.openstack.org/#/c/391597/