heads/initrd/bin/kexec-save-default

#!/bin/sh
# Save these options to be the persistent default
set -e -o pipefail
. /etc/functions

while getopts "b:d:p:e:i:" arg; do
	case $arg in
		b) bootdir="$OPTARG" ;;
		d) paramsdev="$OPTARG" ;;
		p) paramsdir="$OPTARG" ;;
		i) index="$OPTARG" ;;
	esac
done

if [ -z "$bootdir" -o -z "$index" ]; then
	die "Usage: $0 -b /boot -i menu_option "
fi

if [ -z "$paramsdev" ]; then
	paramsdev="$bootdir"
fi

if [ -z "$paramsdir" ]; then
	paramsdir="$bootdir"
fi

bootdir="${bootdir%%/}"
paramsdev="${paramsdev%%/}"
paramsdir="${paramsdir%%/}"

TMP_MENU_FILE="/tmp/kexec/kexec_menu.txt"
ENTRY_FILE="$paramsdir/kexec_default.$index.txt"
HASH_FILE="$paramsdir/kexec_default_hashes.txt"

if [ ! -r "$TMP_MENU_FILE" ]; then
	die "No menu options available, please run kexec-select-boot"
fi

entry=`head -n $index $TMP_MENU_FILE | tail -1`
if [ -z "$entry" ]; then
	die "Invalid menu index $index"
fi

# try to switch to rw mode
mount -o rw,remount $paramsdev

if [ ! -d $paramsdir ]; then
	mkdir -p $paramsdir \
	|| die "Failed to create params directory"
fi
rm "$paramsdir/kexec_default.*.txt" 2>/dev/null || true
echo "$entry" > $ENTRY_FILE
cd $bootdir && kexec-boot -b "$bootdir" -e "$entry" -f | \
	xargs sha256sum > $HASH_FILE \
|| die "Failed to create hashes of boot files"
if [ ! -r $ENTRY_FILE -o ! -r $HASH_FILE ]; then
	die "Failed to write default config"
fi

# sign and auto-roll config counter
kexec-sign-config -p $paramsdir -u \
|| die "Failed to sign default config"

# switch back to ro mode
mount -o ro,remount $paramsdev