Thursday, January 24, 2019

Fedora 29 : Selinux and python.

Today I tested the selinux python module with Fedora 29.
The wikipedia page comes with this intro about SELinux: Security-Enhanced Linux (SELinux) is a Linux kernel security module that provides a mechanism for supporting access control security policies, including mandatory access controls (MAC). ... A Linux kernel integrating SELinux enforces mandatory access control policies that confine user programs and system services, as well as access to files and network resources.

This kernel module can help you with security the network and running application on your Linux.
This very complex kernel module can be used with your policy configuration files designed to fix your security issues.
First, the install is easy to do with the dnf tool:
[root@desk mythcat]# dnf install python2-libselinux.x86_64 
Last metadata expiration check: 1:31:46 ago on Thu 24 Jan 2019 07:04:16 AM EET.
Dependencies resolved.
...
Installed:
  python2-libselinux-2.8-6.fc29.x86_64                                          

Complete!
I tested this python module with a few simple examples:
[mythcat@desk ~]$ python 
Python 2.7.15 (default, Oct 15 2018, 15:26:09) 
[GCC 8.2.1 20180801 (Red Hat 8.2.1-2)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import selinux
>>> selinux.is_selinux_enabled()
1
>>> selinux.lgetfilecon_raw(".bashrc")
[37, 'unconfined_u:object_r:user_home_t:s0']
>>> selinux.lgetfilecon_raw(".bashrc")
[37, 'unconfined_u:object_r:user_home_t:s0']
>>> selinux.selinux_getpolicytype()[1]
'targeted'
>>> selinux.selinux_getpolicytype()
[0, 'targeted']

Sunday, January 13, 2019

Fedora 29 : The AppImage tool and Krita Next.

The AppImage is a universal software package format.
The process of packaging the software in AppImage is a storage file provide by the developer.
This file is a compressed image with all the dependencies and libraries needed to run the desired software. The AppImage doesn’t really install the software just execute it without no extraction and no installation.
The most common features:
  • Can run on various different Linux distributions;
  • No need of installing and compiling software;
  • No need of root permission and the system files are not touched;
  • Can be run anywhere including live disks;
  • Applications are in read only mode;
  • Software are removed just by just deleting the AppImage file;
  • Applications packaged in AppImage are not sandboxed by default.
More about this can be read at official webpage.
I tested the Krita Next with this tool.
The appimage file of Krita Next can be found here.
About the Krita Next this is a daily builds that contain new features, but could be unstable.
After I download the file I change it to executable with:
[mythcat@desk Downloads]$ chmod +x krita-4.2.0-pre-alpha-95773b5-x86_64.appimage 
[mythcat@desk Downloads]$ ./krita-4.2.0-pre-alpha-95773b5-x86_64.appimage

Monday, January 7, 2019

Fedora 29 : The figlet linux tool.

About this Linux tool you can read at figlet manual :
FIGlet prints its input using large characters (called ``FIGcharac- ters'')made up of ordinary screen characters (called ``sub-charac- ters''). FIGlet output is generally reminiscent of the sort of ``sig- natures'' many people like to put at the end of e-mail and UseNet mes- sages. It is also reminiscent of the output of some banner programs, although it is oriented normally, not sideways. 
...
Let's see some examples:
[root@desk mythcat]# dnf install figlet
Last metadata expiration check: 1:05:53 ago on Mon 07 Jan 2019 06:52:19 PM EET.
Dependencies resolved.

[mythcat@desk ~]$ figlet --h
figlet: invalid option -- '-'
Usage: figlet [ -cklnoprstvxDELNRSWX ] [ -d fontdirectory ]
              [ -f fontfile ] [ -m smushmode ] [ -w outputwidth ]
              [ -C controlfile ] [ -I infocode ] [ message ]

                  

[mythcat@desk ~]$ figlet -v 
FIGlet Copyright (C) 1991-2012 Glenn Chappell, Ian Chai, John Cowan,
Christiaan Keet and Claudio Matsuoka
Internet:  Version: 2.2.5, date: 31 May 2012

FIGlet, along with the various FIGlet fonts and documentation, may be
freely copied and distributed.

If you use FIGlet, please send an e-mail message to .

The latest version of FIGlet is available from the web site,
    http://www.figlet.org/

Usage: figlet [ -cklnoprstvxDELNRSWX ] [ -d fontdirectory ]
              [ -f fontfile ] [ -m smushmode ] [ -w outputwidth ]
              [ -C controlfile ] [ -I infocode ] [ message ]
The messages can be set and show on output like a print similar to an ASCII banner.
The arguments of this tool set to the left, center and right or change size and font:
The simple one can be this:
[mythcat@desk ~]$ figlet 2019