pq/libfreemkv
1
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

libfreemkv 0.31.9: ~3x fewer AES ops in the subset-difference PK walk

Browse Source 
calc_pk_from_dk derived all three children (left/pk/right) at every tree
level but used only the one it descended into; the Processing Key only
matters at the final node. Derive just the descended child per level + the
PK once at the end. Bit-for-bit identical; speeds every DK->MK derivation
(disc decryption + unpositioned-DK recovery). 60.8s -> 22.9s on a UHD
worst-case recovery scan.
This commit is contained in:
Matthew Jackson
2026-06-17 15:43:39 -07:00
parent dc87962e50
commit 9c80ef8245
3 changed files with 23 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files
CHANGELOG.md
+10
View File
@@ -1,5 +1,15 @@
# Changelog
## 0.31.9 (2026-06-17)
### Performance
- Subset-difference PK walk (`calc_pk_from_dk`): at each tree level derive only
the child actually descended into (not both siblings) and compute the
Processing Key once at the final node — ~3x fewer AES block ops per walk.
Bit-for-bit identical output; speeds every Device-Key → Media-Key derivation
(disc decryption AND unpositioned-DK recovery).
## 0.31.8 (2026-06-17)
### Added