Sign & Encrypt your Emails with Thunderbird/Enigmail

Posted on April 8th, 2008 in Applications, Security by admin

Thunderbird is a great and well know open source email client brought to you by the same group that puts out Firefox. But like Firefox, there’s extensions we can add to it to make an already secure application more secure. Welcome to the world of signing and encrypting your emails. This tutorial will already assume you have thunderbird installed, be it your distro’s package or the Mozilla Builds. We will also assume you have installed the Enigmail extension, luckily for me openSuse provides this with their default Thunderbird install from their repo’s. Other’s may have to download and install it from here. And for the last of our assumptions, we will assume you have GnuPG installed as well. Most Linux distributions today include GnuPG by default. To find out if this is the case, get to a command prompt and type gpg –version. If it tells you that you’ve got GnuPG 1.4.9 (or some later version), then you don’t need to do anything: it’s already there. To familiarize yourself with the basics of GPG, look at the man page for it, and also check out a previous entry Tuxtraining has written on the subject.

Use OTR to Encrypt Pidgin Conversations

Posted on April 8th, 2008 in Applications, Security by admin

OTR allows you to have private conversations over instant messaging by providing encryption, authentication, and deniability.  Most distro’s have OTR in the repo’s.    It comes standard with your pidigin installation in Suse.  A search of Synaptic or pruit/yumex in Fedora should easily find OTR as well.  If it is not in your repo’s you can build it from source here: http://www.cypherpunks.ca/otr/#downloads

Binaries are also provided for Windows users as well.

Once installed it’s pretty simple to use, but here’s a walk through:

Get the Flash Player to see this player.

Encrypt files with OpenSSL

Posted on March 10th, 2008 in Security by admin

Need to protect sensitive information?  Then you need an encryption program.  Luckily most linux distrubtions come with openSSL already installed.  I’ve tested this on openSuse and Ubuntu and both seem to have the package right out of the box.

To encrypt a file:  openssl des3 -salt -in existing_file.txt -out file.des3

The above will prompt for a password, or you can put it in with a -k option (as shown below), assuming you’re on a trusted server.

To Decrypt: openssl des3 -d -salt -in file.des3 -out file.txt -k mypassword

Need to encrypt what you type? Enter the following, then start typing and ^D to end.

$ openssl des3 -salt -out new_file_name.txt

Also See:

  1. Encrypt-Decrypt file using GPG
  2. Use Yast to Encrypt Partitions

Use Yast to Encrypt Partitions

Posted on March 5th, 2008 in OpenSuse, Security by admin

Use YaST to encrypt partitions or parts of your file system during installation or in an already installed system. However, encrypting a partition in an already installed system is more difficult, because you have to resize and change existing partitions. In such cases, it may be more convenient to create an encrypted file of a defined size in which to store other files or parts of your file system. To encrypt an entire partition, dedicate a partition for encryption in the partition layout. The standard partitioning proposal as suggested by YaST does not, by default, include an encrypted partition. Add it manually in the partitioning dialog.

How to Encrypt Bit Torrent Traffic With Ktorrent and Azurues

Posted on March 5th, 2008 in Applications by admin

More and more ISP’s are limiting throttling BitTorrent traffic on their networks. By throttling BitTorrent traffic the speed of BitTorrent downloads decrease, and high speed downloads are out of the question.

The list of ISP’s that limit BitTorrent traffic, or plan to do so is growing every day, and according to the BBC, the ‘bandwidth war’ has begun.

Are you not sure if your traffic is being throttled Check the list of bad ISP’s.

But there is a solution. Encrypting your torrents will prevent throttling ISP’s from shaping your traffic. I will explain how to enable encryption in Azureus, ktorrent, Deluge the three most popular torrent clients in Linux.