At KDE Plasma, you can easily lock folders and files with password. This is a newly introduced feature named Plasma Vault. It is available since Plasma 5.11 beta by Ivan Čukić. This means soon Kubuntu will have this feature as well. If want to know how to use it, here’s the simple guide. My thanks for Ivan, this Plasma Vault is awesome and my long-awaited feature of all GNU/Linux desktop!
Is Vault Installed?
If you use Kubuntu or Neon, perhaps, Vault is not installed. To check it, run dpkg. To install it, run apt-get.
This should show one result of plasma-vault:
dpkg -l | grep -i plasma-vault
If it didn’t show any, than do this:
sudo apt-get install plasma-vault
Where’s Vault?
Once installed, Vault appears as “black lock icon” on bottom panel on your KDE Plasma along with Net, Battery, and Volume indicators. If it doesn’t appear there, add it yourself by adding new Plasma Widget.
Create a Vault First
Click the Vault icon > create new vault > type a name for it >
see the warning of CryFS encryption technology >
create a password to lock your new vault (this password will be used to unlock your folder) >
see the folders locations >
see the cipher choice (choosing the default is OK) > press Create > finish.
The result is a folder named “My Secret Folder!” inside a folder named Vaults in my $HOME folder. And, Vault indicator shows one vault named “My Secret Folder”. You can create unlimited number of vaults with Plasma Vault.
See your Dolphin:
See your Vault indicator:
 |
| My Secret Folder!: unlocked, accessible |
 |
| My Secret Folder!: locked, enter password to unlock it |
Lock A Folder
After creating a vault, now you can add your folders and files into it (use Dolphin), then lock the vault by clicking the black triangle button (on indicator). The result is nobody can open that vault except you the owner of the password above.
The Locked and The Unlocked
See Dolphin at your $HOME folder where the Vaults folder is. If the Vault is locked, then you see no file and no folder inside Vaults. Even if you delete Vaults, you cannot destroy the saved files inside. This is the security system so nobody can access your encrypted data.
If the Vault is unlocked, e.g. you entered the correct password, then Dolphin shows the files and folders stored inside Vaults folder. Only in this state you can modify the files inside or delete them.
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