Use auth_username when probing encrypted rbd volumes while extending them

[Lee Yarwood]

Description
===========

I0c3f14100a18107f7e416293f3d4fcc641ce5e55 introduced new logic around resizing encrypted LUKSv1 volumes that probed the volume using qemu-img to determine the LUKSv1 header size and to take this into account during the resize. The use of qemu-img however assumes access to the admin rbd keyring as a username isn't provided. This isn't always available in all environment so the options `id:$username` need to be appended on the rbd URI provided to qemu-img.

Steps to reproduce
==================

Attempt to resize an encrypted LUKSv1 volume on a compute without access to the admin keyring.

Expected result
===============

The URI provided to qemu-img includes the username (and thus local keyring) to use.

Actual result
=============

qemu-img fails as it can't find the default admin keyring.

Environment
===========
1. Exact version of OpenStack you are running. See the following
  list for all releases: http://docs.openstack.org/releases/

  master

2. Which hypervisor did you use?
   (For example: Libvirt + KVM, Libvirt + XEN, Hyper-V, PowerKVM, ...)
   What's the version of that?

   libvirt + KVM

2. Which storage type did you use?
   (For example: Ceph, LVM, GPFS, ...)
   What's the version of that?

   c-vol ceph

3. Which networking type did you use?
   (For example: nova-network, Neutron with OpenVSwitch, ...)

   N/A

Logs & Configs
==============

3e004ad2953a4aa7a2f9022be3ffc7cd - default default] [instance: 8d640d15-30dd-4e72-a9ba-d9f7cf11b1ec] Unknown error when attempting to find the payload_offset for LUKSv1 encrypted disk rbd:volumes/volume-d721825d-038a-42f6-8127-aaec171e5c39.: nova.exception.InvalidDiskInfo: Disk info file is invalid: qemu-img failed to execute on rbd:volumes/volume-d721825d-038a-42f6-8127-aaec171e5c39 : Unexpected error while running command.
Command: /usr/libexec/platform-python -m oslo_concurrency.prlimit --as=1073741824 --cpu=30 -- env LC_ALL=C LANG=C qemu-img info rbd:volumes/volume-d721825d-038a-42f6-8127-aaec171e5c39 --output=json --force-share
Exit code: 1
Stdout: ''
Stdout: ''
Stderr: "qemu-img: Could not open 'rbd:volumes/volume-d721825d-038a-42f6-8127-aaec171e5c39': error connecting: Permission denied\n"

[Lee Yarwood (lyarwood)]

https://review.opendev.org/c/openstack/nova/+/772869

[Lee Yarwood (lyarwood)]

https://bugzilla.redhat.com/show_bug.cgi?id=1921623 downstream bug for this.

[Balazs Gibizer (balazs-gibizer)]

The patch has been merged to master and backports has been proposed to stable/victoria and stable ussuri
https://review.opendev.org/q/Ia6d6dcdd7042f2aef6b3abeb5cd0f7525678a3b7

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/nova 23.0.0.0rc1 release candidate.

[melanie witt (melwitt)]

https://review.opendev.org/c/openstack/nova/+/773443 has merged to stable/victoria

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/nova 21.2.1 release.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/nova 22.2.1 release.