The Marvell 88F6281 SOC (which is in all the plugs at this point) has hardware-based Cryptographic Engines and a Security
Accelerator. The hardware does NOT support every encryption algorithm. Marvell has provided Linux driver(s) to support the hardware and these drivers are in the main Linux tree. The drivers expose the hardware based algorithms.
It is now a question of whether the software you want to run will use the driver(s) that Marvell has provided.
For more about the hardware, take a look at this document:
http://www.marvell.com/products/processors/embedded/kirkwood/FS_88F6180_9x_6281_OpenSource.pdf