tomb binary package in Ubuntu Bionic ppc64el

 Tomb is a free and easy to operate desktop application for fairly strong
 encryption of personal files. A tomb is like a locked folder that can be
 transported and hidden in filesystems; its keys are password protected and can
 be kept separate, for instance keeping the tomb file in your computer's
 harddisk and the key file on a USB stick.
 .
 Tomb relies on dm-crypt (and cryptsetup) as an encryption backend using the
 aes-cbc-essiv:sha256 cypher.

Source package