The best library for encryption and decryption in delphi and lazarus is working in 64 bits now (Only in lazarus/fpc, while embarcadero don't release a 64 bits compiler).
Thanks to the amazing work of David Barton, library creator, we can get enc/dec at faster speeds using 64 bits.
You can download it here
Edited: The project is now hosted in lazarus-ccr project. a unique code builds on both,32 and 64 bits. I dont tested the lazarus-ccr code.