You can use encfs to encrypt a folder in real time. This is useful if you want to sync sensitive information to cloud backup providers like dropbox.
To install encfs, run
apt install encfs
To created an encrypted folder,run
encfs /path/to/encrypted-files ~/my-private-files
Here /path/to/encrypted-files will have all encrypted files. This folder you can specify inside your dropbox folder, for example
encfs ~/Dropbox/encrypted-files ~/my-private-files
root@hon-vpn:~# encfs ~/my-files-secure ~/my-files The directory "/root/my-files-secure/" does not exist. Should it be created? (y,n) y The directory "/root/my-files" does not exist. Should it be created? (y,n) y Creating new encrypted volume. Please choose from one of the following options: enter "x" for expert configuration mode, enter "p" for pre-configured paranoia mode, anything else, or an empty line will select standard mode. ?> p Paranoia configuration selected. Configuration finished. The filesystem to be created has the following properties: Filesystem cipher: "ssl/aes", version 3:0:2 Filename encoding: "nameio/block", version 3:0:1 Key Size: 256 bits Block Size: 1024 bytes, including 8 byte MAC header Each file contains 8 byte header with unique IV data. Filenames encoded using IV chaining mode. File data IV is chained to filename IV. File holes passed through to ciphertext. -------------------------- WARNING -------------------------- The external initialization-vector chaining option has been enabled. This option disables the use of hard links on the filesystem. Without hard links, some programs may not work. The programs 'mutt' and 'procmail' are known to fail. For more information, please see the encfs mailing list. If you would like to choose another configuration setting, please press CTRL-C now to abort and start over. Now you will need to enter a password for your filesystem. You will need to remember this password, as there is absolutely no recovery mechanism. However, the password can be changed later using encfsctl. New Encfs Password: Verify Encfs Password: root@hon-vpn:~#
You will need to mount the volume every time you reboot your PC. You can use gnome-encfs to do this auto, that store password in gnome keyring.