Download: blkcrypt package for Linux
blkcrypt contains the source code for 3 block encryption
algorithms: des, blowfish, idea
Check first if you are allowed to download and use
cryptographic software in your country. If not don't
download.
Idea is patented in the US and can be used freely only or
non-commercial purposes. Therefore do not use this software for
commercial purposes.
Download blkcrypt-1.6.tar.gz
Download
blkcrypt-1.5.tar.gz
Download
blkcrypt-1.4.tar.gz
Download
blkcrypt-1.3.tar.gz
Download
blkcrypt-1.2.tar.gz
Download
blkcrypt-1.1.tar.gz
I created this set of utilities to easily encrypt files in 1998 and I am maintaining it to this date however many things have changed since then. Openssl is now available on any Linux distribution and you can achieve similar results with the "openssl enc" command.
Here is an example on how to encrypt a file using openssl/blowfish:
openssl enc -bf-cbc -pass pass:mysecret -in plaintext.txt -out notreadable.enc
To decrypt the file "notreadable.enc" use the command:
openssl enc -d -bf-cbc -pass pass:mysecret -in notreadable.enc -out plaintext-2.txt
Other links on cryptography: