heads/initrd/bin/kexec-iso-init

#!/bin/sh
# Boot from signed ISO
set -e -o pipefail
. /etc/functions
. /etc/config

MOUNTED_ISO_PATH="$1"
ISO_PATH="$2"
DEV="$3"

echo '+++ Verifying ISO'
# Verify the signature on the hashes
ISOSIG="$MOUNTED_ISO_PATH.sig"
if ! [ -r "$ISOSIG" ]; then
	ISOSIG="$MOUNTED_ISO_PATH.asc"
fi

ISO_PATH="${ISO_PATH##/}"

gpgv --homedir=/etc/distro/ "$ISOSIG" "$MOUNTED_ISO_PATH" \
	|| die 'ISO signature failed'

echo '+++ Mounting ISO and booting'
mount -t iso9660 -o loop $MOUNTED_ISO_PATH /boot \
	|| die '$MOUNTED_ISO_PATH: Unable to mount /boot'

DEV_UUID=`blkid $DEV | tail -1 | tr " " "\n" | grep UUID | cut -d\" -f2`
ADD="fromiso=/dev/disk/by-uuid/$DEV_UUID/$ISO_PATH iso-scan/filename=/${ISO_PATH}"
REMOVE=""

paramsdir="/media/kexec_iso/$ISO_PATH"
check_config $paramsdir

ADD_FILE=/tmp/kexec/kexec_iso_add.txt
if [ -r $ADD_FILE ]; then
	NEW_ADD=`cat $ADD_FILE`
	ADD=$(eval "echo \"$NEW_ADD\"")
	echo "+++ Overriding standard ISO kernel add arguments: $ADD"
fi
REMOVE_FILE=/tmp/kexec/kexec_iso_remove.txt
if [ -r $REMOVE_FILE ]; then
	NEW_REMOVE=`cat $REMOVE_FILE`
	REMOVE=$(eval "echo \"$NEW_REMOVE\"")
	echo "+++ Overriding standard ISO kernel remove arguments: $REMOVE"
fi

# Call kexec and indicate that hashes have been verified
kexec-select-boot -b /boot -d /media -p "$paramsdir" \
	-a "$ADD" -r "$REMOVE" -c "*.cfg" -u -i

die "Something failed in selecting boot"