Modernizing Kernel Cryptography: From Complex APIs To Streamlined Libraries
summary
The kernel adds straightforward library functions (first set landed in 6.17) that replace the traditional crypto API for common one‑shot and incremental ops, e.g., a direct HMAC‑SHA256 function that returns void, works in all contexts, and is two and a half times faster than the old path that cost ~2100 cycles with only 38% spent in core SHA256 (measured with perf). New features include SHAKE support (6.19), ML‑DSA verify (7.0), massive CRC wins — a 12,400% CRC64 throughput boost on AMD — KUnit tests (18 suites), and QEMU CI coverage; AF_ALG has had multiple privilege‑escalation exploits recently.
AI-written summary · about
chapters (14)
- 0:00Kernel crypto modernization
- 1:05Why kernel crypto exists
- 2:09Traditional crypto API problems
- 3:52HMAC-SHA-256 pitfalls
- 6:19Crypto library approach
- 9:13ChaCha20-Poly1305 flaws
- 12:24Current crypto and CRC libraries
- 14:10Recent crypto improvements
- 18:07Testing crypto libraries
- 20:34Library vs traditional API
- 21:37Choosing algorithms
- 23:23AF_ALG risks and deprecation
- 25:30Summary and future
- 26:20Q&A
related talks
51mAn Overview of the Linux Kernel Crypto Subsystem
51mThe Linux Crypto API
36mCryptodev and Security Library Updates in DPDK
30mFacing Extinction: The Fight To Keep Hardware Crypto Engines in Embedded Linux
47mLinux Cryptographic Acceleration on an i.MX6
14mUsing Proposed Vector And Crypto Extensions For Fast And Secure Boot
34m"The Cryptography State of the Union"
13mEnabling Crypto Agility by Immunizing Processors Against the Exploitation of Software Bugs