This adds three new settings to the cipher dialog: KDF iterations, HMAC
algorithm, and KDF algorithm. To simplify things we also add two presets
for all the encryption settings: SQLCipher3 defaults and SQLCipher4
defaults. The preselected default is chosen depending on the SQLCipher
version which we use.
This should work with any combination of SQLCipher3 and SQLCipher4 and
any database created by either. It should also work with DotEnv files as
expected. Again, the defaults which are used for missing values in the
DotEnv files are chosen depending on the SQLCipher version we use.
* Make sure only powers of two are entered for the page size
* Replace QSpinBox with QComboBox
Having a QSpinBox didn't make too much sense when we only have 8 valid
values. Forcing the user to type a valid value would have required a
warning message too, along with translations.
Having a QComboBox makes it clear (obviously) what values we are
expecting, without any risk of invalid values or confusion.
* Add thousands separator for page size values
Change the tab order in the encryption dialog so that the password
editor is the widget that is selected by default. That makes it possible
to type in the passphrase right away without navigating to the widget
first.
Add a new menu option to the main window (only visible when built with
the sqlcipher option enabled) which opens a dialog asking for new
encryption settings. These are then applied to a new database to which
all contents of the current one are exported. The old database is then
replaced by the new one.
This adds support for encrypting plaintext databases, decrypting
encrypted databases and changing the password or other settings of
encrypted databases.
If this turns out to work well enough we have functional SQLCipher
encryption support with only details missing.
Fix the sqlcipher build option in the qmake project to actually enable
the SQLCipher support.
Add a new dialog called CipherDialog which is used to ask the user for
the password and other encryption details instead of using standard Qt
input dialogs.
