Unsigning a signed jar

Question

I am using bouncy castle provider for AES encryption. I need to create a fat jar from bc and my jar but as soon as i do it i get Algorithm not found exception. Is it possible to get rid of the sign and create regular jar out of it?

My build process is..

• i unzip all jars in to my build directory.
• then remove META-INF directory
• compile my application
• jar it using ant

iget the error when i try to use the

SecretKeyFactory.getInstance(algorithm);

algorithm is PBEWITHSHA256AND128BITAES-CBC-BC from bouncy castle.

Answer 1

To remove the signature from a jar file, remove the META-INF directory from it. A jar file is a zip file so on Linux you can do this:

zip -d file.jar 'META-INF/*.SF' 'META-INF/*.RSA'

Answer 2

When you sign a jar file, new files get added to the META-INF directory, e.g. "MKSIGN.SF" and "MKSIGN.DSA". Just remove them from the jar file (with any zip utility), and you have it unsigned.