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(parent: d3f33b9) | patch
symm/des-base.h: Improve the IP permutation network.
authorMark Wooding <mdw@distorted.org.uk>
Thu, 1 Feb 2024 14:29:06 +0000 (14:29 +0000)
committerMark Wooding <mdw@distorted.org.uk>
Thu, 1 Feb 2024 14:29:06 +0000 (14:29 +0000)
commit48af823d9b5218ce32d7590b786d3b1cd089b68c
treef2e64d28dcf241c85b0fa93fa59b2743df569ed4tree | snapshot (tar.gz zip)
parentd3f33b9a37f45bc5809af314b1b436b712d59a80commit | diff
symm/des-base.h: Improve the IP permutation network.

The new network is the same number of steps as the old one, but by
exchanging bits between the two halves, we reduce the number of CPU
operations needed to perform the permutation.

This is the same network used by PuTTY, but I derived it independently.
symm/des-base.h diff | blob | blame | history
utils/permute.lisp diff | blob | blame | history
Catacomb cryptographic library