Question

Our application needs to encrypt/decrypt files using (for instance) Blowfish encryption algorithm. We know bcrypt could be a good choice, but it cannot be called directly from our application (as it prompts for key phrase).

Which is the best existing option?

We prefer a Windows tool, though Linux would be good as well.

Answer 1

http://www.openssl.org/docs/crypto/blowfish.html programming interface

http://www.openssl.org/docs/apps/enc.html command line interface

Example:

openssl enc -base64 -e -bf-cbc -in <infile> -out <outfile> -kfile <passphrase file>

(replace -e with -d to decrypt)