Merge pull request #25319 from zx2c4-forks/krngseed

boot: implement kernel EFI RNG seed protocol with proper hashing

man/systemd-boot.xml

@@ -435,28 +435,6 @@
         to view this data. </para></listitem>
       </varlistentry>
 
-      <varlistentry>
-        <term><varname>LoaderRandomSeed</varname></term>
-
-        <listitem><para>A binary random seed <command>systemd-boot</command> may optionally pass to the
-        OS. This is a volatile EFI variable that is hashed at boot from the combination of a random seed
-        stored in the ESP (in <filename>/loader/random-seed</filename>) and a "system token" persistently
-        stored in the EFI variable <varname>LoaderSystemToken</varname> (see below). During early OS boot the
-        system manager reads this variable and passes it to the OS kernel's random pool, crediting the full
-        entropy it contains. This is an efficient way to ensure the system starts up with a fully initialized
-        kernel random pool — as early as the initrd phase. <command>systemd-boot</command> reads
-        the random seed from the ESP, combines it with the "system token", and both derives a new random seed
-        to update in-place the seed stored in the ESP, and the random seed to pass to the OS from it via
-        SHA256 hashing in counter mode. This ensures that different physical systems that boot the same
-        "golden" OS image — i.e. containing the same random seed file in the ESP — will still pass a
-        different random seed to the OS. It is made sure the random seed stored in the ESP is fully
-        overwritten before the OS is booted, to ensure different random seed data is used between subsequent
-        boots.</para>
-
-        <para>See <ulink url="https://systemd.io/RANDOM_SEEDS">Random Seeds</ulink> for
-        further information.</para></listitem>
-      </varlistentry>
-
       <varlistentry>
         <term><varname>LoaderSystemToken</varname></term>