Import static grub configuration

Pull this from coreos-assembler; prep for moving ownership
of it into bootupd.  The big change though is the addition of
sourcing a `platform.cfg` which is where we'll put the stuff
that currently lives in `platforms.yaml` in FCOS as well as
the Ignition glue.

This glue can be used as is by Sagano, where the base images don't
need the Ignition glue or platforms.yaml.

Makefile

@@ -44,3 +44,6 @@ install: install-units
 	ln -f ${DESTDIR}$(LIBEXECDIR)/bootupd ${DESTDIR}$(PREFIX)/bin/bootupctl
 	install -d "${DESTDIR}$(PREFIX)/lib/systemd/system/multi-user.target.wants"
 	ln -s ../bootupd.socket "${DESTDIR}$(PREFIX)/lib/systemd/system/multi-user.target.wants"
+
+install-grub-static:
+	install -D -t ${DESTDIR}$(PREFIX)/lib/bootupd/grub2-static src/grub2/*.cfg

contrib/packaging/bootupd.spec

@@ -44,11 +44,21 @@ replace-with = "vendored-sources"
 directory = "vendor"
 EOF
 
+%package grub2-static
+Summary: Static grub2 configuration files for CoreOS-alike systems
+
+%description grub2-static
+Theis package includes static grub2 configuration files.
+
+%files grub2-static
+%{_prefix}/lib/bootupd
+
 %build
 cargo build --release
 
 %install
 %make_install INSTALL="install -p -c"
+make install-grub-static DESTDIR=%{?buildroot} INSTALL="%{__install} -p"
 
 %post        -n %{crate}
 %systemd_post bootupd.service bootupd.socket

src/grub2/README.md

@@ -0,0 +1,3 @@
+# Static GRUB configuration files
+
+These static files were taken from https://github.com/coreos/coreos-assembler/blob/5824720ec3a9ec291532b23b349b6d8d8b2e9edd/src/grub.cfg

src/grub2/grub-static-efi.cfg

@@ -0,0 +1,19 @@
+if [ -e (md/md-boot) ]; then
+  # The search command might pick a RAID component rather than the RAID,
+  # since the /boot RAID currently uses superblock 1.0.  See the comment in
+  # the main grub.cfg.
+  set prefix=md/md-boot
+else
+  if [ -f ${config_directory}/bootuuid.cfg ]; then
+    source ${config_directory}/bootuuid.cfg
+  fi
+  if [ -n "${BOOT_UUID}" ]; then
+    search --fs-uuid "${BOOT_UUID}" --set prefix --no-floppy
+  else
+    search --label boot --set prefix --no-floppy
+  fi
+fi
+set prefix=($prefix)/grub2
+configfile $prefix/grub.cfg
+boot
+

src/grub2/grub-static.cfg

@@ -0,0 +1,83 @@
+# This file is copied from https://github.com/coreos/coreos-assembler/blob/main/src/grub.cfg
+# Changes:
+#   - Dropped Ignition glue, that can be injected into platform.cfg
+# set pager=1
+# petitboot doesn't support -e and doesn't support an empty path part
+if [ -d (md/md-boot)/grub2 ]; then
+  # fcct currently creates /boot RAID with superblock 1.0, which allows
+  # component partitions to be read directly as filesystems.  This is
+  # necessary because transposefs doesn't yet rerun grub2-install on BIOS,
+  # so GRUB still expects /boot to be a partition on the first disk.
+  #
+  # There are two consequences:
+  # 1. On BIOS and UEFI, the search command might pick an individual RAID
+  #    component, but we want it to use the full RAID in case there are bad
+  #    sectors etc.  The undocumented --hint option is supposed to support
+  #    this sort of override, but it doesn't seem to work, so we set $boot
+  #    directly.
+  # 2. On BIOS, the "normal" module has already been loaded from an
+  #    individual RAID component, and $prefix still points there.  We want
+  #    future module loads to come from the RAID, so we reset $prefix.
+  #    (On UEFI, the stub grub.cfg has already set $prefix properly.)
+  set boot=md/md-boot
+  set prefix=($boot)/grub2
+else
+  if [ -f ${config_directory}/bootuuid.cfg ]; then
+    source ${config_directory}/bootuuid.cfg
+  fi
+  if [ -n "${BOOT_UUID}" ]; then
+    search --fs-uuid "${BOOT_UUID}" --set boot --no-floppy
+  else
+    search --label boot --set boot --no-floppy
+  fi
+fi
+set root=$boot
+
+if [ -f ${config_directory}/grubenv ]; then
+  load_env -f ${config_directory}/grubenv
+elif [ -s $prefix/grubenv ]; then
+  load_env
+fi
+
+if [ x"${feature_menuentry_id}" = xy ]; then
+  menuentry_id_option="--id"
+else
+  menuentry_id_option=""
+fi
+
+function load_video {
+  if [ x$feature_all_video_module = xy ]; then
+    insmod all_video
+  else
+    insmod efi_gop
+    insmod efi_uga
+    insmod ieee1275_fb
+    insmod vbe
+    insmod vga
+    insmod video_bochs
+    insmod video_cirrus
+  fi
+}
+
+# tracker: https://github.com/coreos/fedora-coreos-tracker/issues/805
+if [ -f $prefix/platform.cfg ]; then
+  source $prefix/platform.cfg
+fi
+
+if [ x$feature_timeout_style = xy ] ; then
+  set timeout_style=menu
+  set timeout=1
+# Fallback normal timeout code in case the timeout_style feature is
+# unavailable.
+else
+  set timeout=1
+fi
+
+# Import user defined configuration
+# tracker: https://github.com/coreos/fedora-coreos-tracker/issues/805
+if [ -f $prefix/user.cfg ]; then
+  source $prefix/user.cfg
+fi
+
+blscfg
+