mirror/gmsm
1
0
Fork 0
mirror of https://github.com/emmansun/gmsm.git synced 2025-05-11 03:26:17 +08:00
Code Issues Packages Projects Releases Wiki Activity

Updated 无进位乘法和GHASH (markdown)

Sun Yimin 2023-08-21 15:11:27 +08:00
parent 77a16990ec
commit ba71f11556
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
无进位乘法和GHASH.md

@ -56,8 +56,8 @@ vpxor T1, T1, T4 ; result in T1
* 4-way expanded Horner form (aggregate results to defer the reduction)
* $MM[X_i , Hx] \oplus MM[X_{i-1} , {(Hx)}^2] \oplus MM[X_{i-2} , {(Hx)}^3] \oplus MM[(X_{i-3} \oplus Y_{i-4}, {(Hx)}^4] $
* Can be expanded to N > 4 blocks, we use 8 blocks now.
* Overhead: pre-calculate the powers of Hx (amortized for reasonably long buffer)
* The gain: reduction deffered to once per "N" blocks
* Overhead: pre-calculate the powers of $H \cdot x$ (amortized for reasonably long buffer)
* The gain: reduction deferred to once per "N" blocks
# 参考
* [Cryptographic Hardware and Software and useful architectures](https://www.esat.kuleuven.be/cosic/events/ecrypt-net-school-2018/wp-content/uploads/sites/23/2018/10/kos-school-gueron-2.pdf)