Java implementation of DES for university cryptography course, only ECB mode is implemented (weak I know..)
Mostly used BigInteger class and String Manipulation to do bit operations
DES is the Data Encryption Standard, predecessor of the AES block cipher widely used today
It is 64-bit and as specified in FIPS Pub 46
Download the DES.java file
Open Terminal and cd into directory you downloaded to
eg. cd ~/Downloads/DES
Compile the java file
javac -c DES.java
Now you can run with
javaw DES.jar -k1 <key> -m <message_to_encrypt>
and the program will print the encrypted message to standard output
To Decrypt simply add the -d option
eg. javaw DES.jar -d -k1 <key> -m <message_to_decrypt>
To use TripleDES encryption provide three keys like so:
javaw DES.jar -k1 <key1> -k2 <key2> -k3 <key3> -m <message_to_encrypt>
And for decryption again use -d:
javaw DES.jar -d -k1 <key1> -k2 <key2> -k3 <key3> -m <message_to_decrypt>