CHROMIUM: scripts: change dm_verity alg to sha256
Change dm_verity hash algorithm fom sha1 to sha256.
Due to collision attacks against SHA1 and increasing severity of
collisions there is a need to change the hash algorithm to SHA256.
BUG=chromium:719966
TEST=Bootperf tool is used to make the boot performance measurements.
Boot time measurements taken from kernel start to login screen from high
performance/ low power ARM and x86 platforms show that changing
dm_verity hash algorithm from SHA1 to SHA256 has boot time changes less
than 277 ms on chrome_main when the crypto accelerators(for ARM) and
SSSE3(for x86) kernel configurations are enabled. The difference is less
for higher kernel versions and newer CPUs. For new kernel versions and
CPUs the changes even increase boot time performance upto 717 ms..
Results are on go/cros-boot-sha256.
Cq-Depend: chromium:1648858, chromium:1649075, chromium:1650153, chromium:1647547
Change-Id: I427415c5faf429c499471357ff3e8ffd314650a8
Reviewed-on: https://chromium-review.googlesource.com/1648943
Tested-by: Betul Soysal <betuls@google.com>
Commit-Ready: Betul Soysal <betuls@google.com>
Legacy-Commit-Queue: Commit Bot <commit-bot@chromium.org>
Reviewed-by: Alex Klein <saklein@chromium.org>
Reviewed-by: Mattias Nissler <mnissler@chromium.org>
2 files changed
