Encrypt given data using bf cipher algo. Blowfish is a symmetric key block cipher with a variable key length from 32 bits to 448 bits. Designed by Bruce Schneier in 1993 as a fast, compact alternative to existing encryption algorithms. Considered somewhat insecure for modern use due to small block size (64-bit), but still widely used in legacy systems. Our encryption process prepends the IV string used during the encryption process in the encrypted data so that it can be used during decryption.