Explore the intricacies of the Linux kernel's cryptographic subsystem in this comprehensive conference talk. Delve into the inner workings of the subsystem, learning how kernel users can leverage its capabilities. Examine the official userspace interface that exposes these features and discover non-upstream alternatives. Gain insights into when to use hardware engines versus software-based implementations. Investigate the components of a crypto engine driver and understand the necessary precautions for development. Begin with a brief introduction to cryptographic algorithms before addressing these key topics. Benefit from the expertise of Boris Brezillon, a seasoned embedded systems developer and Linux kernel contributor, as he shares his knowledge on the Marvell CESA cryptographic engine, MTD NAND subsystem, and support for Atmel and Allwinner ARM SoCs in the Linux kernel.