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Mac4lin - Give that Mac OS X look to Linux

Mac4Lin is best Mac like User Interface for Gnome and Xfce desktops like Ubuntu/Xubuntu, Fedora, Debian and others, that will take care of absolutely everything (from icons, themes to usplash – loading window at start) to look just like Mac. With this package comes: dock, the GTK theme, Emerald theme (3d window borders), new icons, new wallpapers, taskbar image, GDM themes, cursors, themes for Pidgin, Firefox, music players and system sounds and you will be amazed of flexibility and customization of Linux system.

Features:

    * Fully supports GNOME 2.26 and backwards compatible
    * Improved support for GlobalMenu, support integrated in the default GTK theme
    * Better native Xfce support
    * Icon additions
    * Statusbar is now fixed
    * New progress bars
    * New tabs
    * Improved installation and uninstallation scripts
    * Integrates well with Globus
    * Finer UI refinements
    * Metacity theme now supports different button sizes
    * Firefox 3 themes are now updated
    * Songbird plugins included
    * Pidgin AWN 64bit plugin now included
    * Fonts are now consolidated
    * Transparent top panel
    * GDM theme is now in-line with Mac OS X login window
    * Cairo dock is the default recommended dock

Issues:

* Usplash is still buggy
* Thunderbird theme is still buggy
* GDM theme is not automatically set by the script

Installation:

Download Mac4Lin file and extract the archive. Run the Mac4Lin installation script (./Mac4Lin_Install_v1.0.sh) as a normal user to install Mac4Lin.

If you'd like to manually install or apply some tweaks, check out the Mac4Lin documentation for advanced installation instructions.

Also, download entire sets of Mac Leopard Wallpapers

Complete and Reliable Password Manager for OpenSuSe - KeepassX

KeePassX is a password manager or safe which helps you to manage your passwords in a secure way. You can put all your passwords in one database, which is locked with one master key or a key-disk.

This means that you only have to remember one single master password or insert the key-disk to unlock the whole database. The complete database is always encrypted either with AES (alias Rijndael) or Twofish encryption algorithm using a 256 bit key. Therefore the saved information can be considered as quite safe.

KeePassX offers a little utility for secure password generation. The password generator is very customizable, fast and easy to use. Especially someone who generates passwords frequently will appreciate this feature.

Installation of KeePassX: use "1-click" installer to install KeePassX
OpenSuSe 11.1 - install KeePassX
OpenSuSe 11.0 - install KeePassX

After successful installation go to command prompt and type command: keepassx to start the application, now go to File menu and create a new database to store the information, here you also have to provide your master key to open/lock this database so DO NOT FORGET THIS PASSWORD.

After creating the secure database click on "Add new entry" to enter and save your password and you should see something like shown below ... here you can also tell KeePassX to generate the secure password.

Save the changes to return back to the main screen and whenever you need to provide the username and password you can use the feature of "copy password to clipboard" or "copy username to clipboard" of KeePassX.

I hope this tutorial has been useful for you too! If you've enjoyed this post, please consider subscribing to Linuxpoison for future updates and more.

Hiding secret data into image and audio files (OpenSuSe)

Steghide is a steganography program that is able to hide data in various kinds of image and audio files. The color-frequencies (for image files) or sample-frequencies (for audio files) are not changed, thus making the embedding resistant against first-order statistical tests.

Features include:
    * Compression of embedded data
    * Encryption of embedded data
    * Embedding of a checksum to verify the integrity of the extraced data
    * Support for JPEG, BMP, WAV and AU files

Installation:
You should have the following packages (libraries) installed to use steghide. (you can get all these lib from software.opensuse.org) Mhash, MCrypt, libjpeg, zlib

Download the rpm file for Steghide
Install this rpm file using command: # rpm -ivh steghide-0.5.1-1.i386.rpm

The basic usage is as follows: Go to command prompt and use following commands

$ steghide embed -cf image.jpeg -ef file.txt
Enter passphrase:
Re-Enter passphrase:
embedding "file.txt" in "image.jpeg"... done

This command will embed the file file.txt in the cover file image.jpeg.

After you have embedded your secret data as shown above you can send the file image.jpeg to the person who should receive the secret message. The receiver has to use steghide in the following way:

$ teghide extract -sf image.jpeg
Enter passphrase:
the file "file.txt" does already exist. overwrite ? (y/n) y
wrote extracted data to "file.txt".

If the supplied passphrase is correct, the contents of the original file file.txt will be extracted from the stego file image.jpeg and saved in the current directory.

If you have received a file that contains embedded data and you want to get some information about it before extracting it, use the info command:

$ steghide info image.jpeg
"image.jpeg":
format: jpeg
capacity: 9.9 KB
Try to get information about embedded data ? (y/n) y
Enter passphrase:
embedded file "file.txt":
    size: 129.0 Byte
    encrypted: rijndael-128, cbc
    compressed: yes

Archiving, Encryption and File split tool - PeaZip

PeaZip is a cross-platform portable file archiver, released under LGPL.

PeaZip supports many different archive and compression formats including: 7z, 7z-sfx, ARC/WRC, BZ2, GZ, LPAQ, PAQ, PEA, QUAD, split, TAR, UPX, ZIP; Read: 7Z, ARC/WRC, ACE, ARJ, BZ2/TBZ2, CAB, CHM, CPIO, DEB, GZ/TGZ, ISO, JAR/EAR/WAR, LZH, NSIS, OOo, PAK/PK3/PK4, PAQ, PEA, PET/PUP, QUAD, RAR, RPM, SLP, split, TAR, U3P, WIM, XPI, Z/TZ, and ZIP/SMZIP.

PeaZip is developed in FreePascal using the Lazarus development environment.
PeaZip can be easily integrated with GNOME and KDE.

Features include:
    * Volume spanning
    * Compression
    * Authenticiated encrpytion
          o 7Z, with AES256 encryption
          o ARC, with AES256, Blowfish, Twofish256 and Serpent256 encryption
          o PEA, with AES256 authenticated encryption (EAX mode)
          o ZIP with WinZip's AE encryption based on AES256
          o ARC format protects archives against corruption employing recovery records
    * Edit, save and restore archive layouts
    * Apply multiple filters to archive contents
    * Handle multiple archives simultaneously
    * Split/join files
    * Wipe files (secure deletion
    * Compare, checksum and has files
    * System benchmark
    * Generate random passwords and key files

Installation of PeaZip:
PeaZip for openSUSE (PackMan)
PeaZip for Mandriva (MIB Mandriva Italia Backports)
Ubuntu/Debian (DEB)
Fedora (rpm)

After successful installation of PeaZip go to console and type command: peazip to open up the application

DenyHosts Installation and Configuration on OpenSuSe

DenyHosts is a script intended to be run by Linux system administrators to help thwart SSH server attacks (also known as dictionary based attacks and brute force attacks).

If you've ever looked at your ssh log (/var/log/secure on Redhat, /var/log/messages on OpenSuSe, etc...) you may be alarmed to see how many hackers attempted to gain access to your server. Hopefully, none of them were successful (but then again, how would you know?). Wouldn't it be better to automatically prevent that attacker from continuing to gain entry into your system?

DenyHosts attempts to address the above... and more by by monitoring invalid login attempts in the authentication log and blocking the originating IP addresses, adding entries to /etc/hosts.deny. DenyHosts will also inform Linux administrators about offending hosts, attacked users and suspicious logins.

Features include:
    * Parses authentication log to find all login attempts and filters failed and successful attempts
    * Synchronization mode allows DenyHosts daemons the ability to share data via a centralized server to proactively thwart attacks
    * DenyHosts Can be run from the command line, cron or as a daemon
    * Records all failed login attempts for the user and offending host
    * For each host that exceeds a threshold count, records the evil host
    * Keeps track of each non-existent user when a login attempt failed
    * Keeps track of each existing user (eg. root) when a login attempt failed
    * Keeps track of each offending host
    * Keeps track of suspicious logins (that is, logins that were successful for a host that had many login failures)
    * Keeps track of the file offset, so that you can reparse the same file (/var/log/secure) continuously (until it is rotated).
    * When the log file is rotated, the script will detect it and parse from the beginning
    * Appends /etc/hosts.deny and adds the newly banned hosts
    * Optionally sends an email of newly banned hosts and suspicious logins
    * Keeps a history of all user, host, user/host combo and suspicious logins encountered which includes the data and number of corresponding failed login attempts
    * Maintains failed valid and invalid user login attempts in separate files, such that it is easy to see which valid user is under attack (which would give you the opportunity to remove the account, change the password or change it's default shell to something like /sbin/nologin
    * Upon each run, the script will load the previously saved data and re-use it to append new failures
    * Resolves IP addresses to hostnames, if available
    * /etc/hosts.deny entries can be expired (purge) at a user specified time

Installation: Use "1-click" installer to install DenyHosts
OpenSuSe 11.1 - Install DenyHosts
OpenSuSe 11.0 - Install DenyHosts

Configuration of Denyhosts:
You can find the main configuration: /etc/denyhosts.conf where most of the settings are good for any normal operation of DenyHosts but you can also tweak it more to suite your needs. look into the comments in this file to know more about the configuration details

Few other important setting:

# vi /var/lib/denyhosts/allowed-hosts
# vi /etc/hosts.allow

you'll want to add in these 2 files the IP(s) you will use to connect to your system that's running Denyhosts so that you aren't inadvertently denied access to your own system(s).

Starting the service and marking it to run on each system reboot:
# service denyhosts start; chkconfig --level 2345 denyhosts on