john software package provides active password cracking tool, you can install in your Ubuntu 16.04 LTS (Xenial Xerus) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install john
john is installed in your system.
Make ensure the john package were installed using the commands given below,
$ sudo dpkg-query -l | grep john *
You will get with john package name, version, architecture and description in a table
| Distro | Ubuntu 16 04 lts xenial xerus |
| Section | Administration Utilities |
| Package | john |
| Version | 1.8.0-2 |
| Description | active password cracking tool |
| Sub Section | admin |