Storage proposal: always do a clean install

[ancorgs]

Problem

D-Installer uses the Y2Storage::GuidedProposal under the hood. But some aspects of the default settings that make sense in the case of YaST and SLE/Leap are wrong or confusing for D-Installer and ALP.

• First of all, we still don't have a mechanism in D-Installer to configure what should be deleted/resized/kept in the affected disk(s). So it's more consistent and understandable to simply wipe the whole content of the disk. That's what the initial UI (being implemented at Storage proposal UI #321) will reflect with a sentence like "install using device /dev/xxx and deleting all its content".
• When using LVM, YaST tries to reuse existing volume groups. We don't want to do the same in D-Installer (for now, at least) because that has proven to be confusing and, somehow, in conflict with the previous point about deleting everything.

Additionally, when encrypting a volume in ALP that should be done with LUKS2 using PBKDF2 as key derivation function. All other "products" known by D-Installer use the traditional LUKS1.

See more at: https://trello.com/c/DWTHEhgU/3230-2-d-installer-adjust-storage-proposal-settings

Solution

• Consistent delete-all behavior enforced in the Y2Storage::ProposalSettings with a method marked as temporary.
• The settings encryption_method and encryption_pbkdf are now configurable per-product at d-installer.yaml.
• ALP configured to use LUKS2 with PBKDF2

Bonus: fixed a hardcoded "1234" at #hack_olaf_password.

Bonus2: added #338 to the changelog.

Testing

• Added unit tests
• Tested manually. It indeed deletes all existing partitions and uses LUKS2 for ALP.

Relations

Depends on yast/yast-storage-ng#1316

[coveralls]

Coverage increased (+0.2%) to 74.878% when pulling e586908 on adjust_proposal_settings into 27cfff5 on master.

[yast-bot]

❌ Public Jenkins job #2 failed