The gnome-disks utility allows users to select LUKS+EXT4 without having cryptsetup installed

[Ben Mathews]

Using a clean install of Ubuntu 16.04, the gnome-disks utility offers users the option of selecting UKS+EXT4 when formatting disks. This fails with:

Error creating LUKS device: Error spawning command-line `cryptsetup luksOpen "/dev/sdb" "': Failed to execute child process "cryptsetup" (No such file or directory) (g-exec-error-quark, 8) (udisks-error-quark, 0)

Installing the cryptsetup package resolves this error.

Suggested resolution:
1) Don't offer LUKS+EXT4 as an option if cryptsetup is not installed
 - or -
2) Rather than failing in the current manner, suggest to the user to install cryptsetup
 - or -
3) Include cryptsetup in the base install by default

Additional information:
1) Release of Ubuntu I am using:
 Description: Ubuntu 16.04 LTS
 Release: 16.04

2) The version of the package I are using:
gnome-disk-utility:
  Installed: 3.18.3.1-1ubuntu1
  Candidate: 3.18.3.1-1ubuntu1
  Version table:
 *** 3.18.3.1-1ubuntu1 500
        500 http://us.archive.ubuntu.com/ubuntu xenial/main amd64 Packages
        100 /var/lib/dpkg/status

3) What I expected to happen: See above

4) What happened instead: See above

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: gnome-disk-utility 3.18.3.1-1ubuntu1
ProcVersionSignature: Ubuntu 4.4.0-22.39-generic 4.4.8
Uname: Linux 4.4.0-22-generic x86_64
ApportVersion: 2.20.1-0ubuntu2
Architecture: amd64
CurrentDesktop: X-Cinnamon
Date: Sun May 15 10:22:40 2016
InstallationDate: Installed on 2016-04-22 (23 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
SourcePackage: gnome-disk-utility
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.