Preserve random seed across reboots
At first I tried to just use systemd's systemd-random-seed, but that one
does not actually use an appropriate ioctl for persuading kernel that
entropy is there. There's a patch [1] for this, but its fate is far from
certain, and even with it, I am not completely sure that I got
everything working correctly (some boots were quick, others waited for
systemd-resolved in the same manner as before this patch).
In the end, just seeding stuff from the initrd [2] is much easier. A
downside is that the systemd unit systemd-random-seed.service will add
the contents of that file once again -- but that doesn't matter much
because we do not patch it, and therefore it does not increase kernel's
idea about available entropy.
Changes from that upstream rndaddentropy:
- larger buffer
- more conservative entropy contribution
[1] https://github.com/systemd/systemd/pull/10621 .
[2] https://github.com/rfinnie/twuewand/blob/master/rndaddentropy/rndaddentropy.c
Change-Id: Ibe3c926c241d75fb7d7c40f3df2a96813931971b
diff --git a/package/czechlight-rauc/rauc-hook.sh b/package/czechlight-rauc/rauc-hook.sh
index 9850c38..5b14883 100755
--- a/package/czechlight-rauc/rauc-hook.sh
+++ b/package/czechlight-rauc/rauc-hook.sh
@@ -4,7 +4,7 @@
slot-post-install)
case "$RAUC_SLOT_CLASS" in
cfg)
- for DIR in etc ssh-user-auth; do
+ for DIR in etc random-seed ssh-user-auth; do
if [[ -d /cfg/$DIR ]]; then
cp -a /cfg/$DIR ${RAUC_SLOT_MOUNT_POINT}/
fi