hpe-iso-build.sh

#!/bin/bash
# (C) Copyright 2021-2022,2024 Hewlett Packard Enterprise Development LP
#
# This script will repack Debian .ISO file for a GLM
# Debian install service that uses Virtual Media
# to get the install started.

# The following changes are being made to the Debian .ISO:
#   (1) configure to use a preseed file on the iLO vmedia-cd
#   (2) setup for a text based install (versus a GUI install)
#   (3) set up the console to the iLO serial port (/dev/ttyS1)

# The Debian .ISO is configured to use a preseed file on the iLO
# vmedia-cd by adding the 'inst.ks=hd:sr0:/hpe-preseed.cfg.template' option in
# GRUB (used in UEFI) and isolinux (used in BIOS) configuration
# files. This option configures Debian installer to pull the
# preseed file from the root of the cdrom at /hpe-preseed.cfg.template.  This
# preseed option is setup by modifying the following files
# on the .ISO:
#   isolinux/isolinux.cfg for BIOS
#   EFI/BOOT/grub.cfg for UEFI

# Usage:
#  hpe-iso-build.sh -i <debian.iso> -o <hpe-customizied-debian.iso>

# command line options            | Description
# ------------------------------- | -----------
# -i <debian.iso>                 | Input Debian .ISO filename
# -o <hpe-customizied-debian.iso> | Output GLM Debian .ISO file

set -exuo pipefail

# make sure we have enough permissions to mount .iso, etc
if [ "$EUID" -ne 0 ]
  then echo "Please run as root"
  exit -1
fi

# check to make sure we have the required tools called within this script
for i in xorriso implantisomd5
do
  which $i > /dev/null 2>&1
  if [ $? -ne 0 ]
  then
    echo "$i not found. Please install."
    exit -1
  fi
done

if [ ! -f "/usr/lib/ISOLINUX/isohdpfx.bin" ]
then
  echo "/usr/lib/ISOLINUX/isohdpfx.bin not found. Please install 'isolinux' package."
  exit -1
fi

UEFI_ORIG_CFG_FILE=""
INPUT_ISO_FILENAME=""
CUSTOM_ISO_FILENAME=""
# parse command line parameters
while getopts "i:o:" opt
do
    case $opt in
        i) INPUT_ISO_FILENAME=$OPTARG
            if [[ ! -f $INPUT_ISO_FILENAME ]]
            then
                echo "ERROR missing image file $INPUT_ISO_FILENAME"
                exit -1
            fi
            ;;
        o) CUSTOM_ISO_FILENAME=$OPTARG ;;
    esac
done

if [ -z "$INPUT_ISO_FILENAME" -o -z "$CUSTOM_ISO_FILENAME" ]; then
   echo "Usage: $0 -i <debian.iso> -o <hpe-customizied-debian.iso>"
   exit 1
fi

# Generate unique ID for use as the uploaded file name.
ID=$RANDOM
YYYYMMDD=$(date '+%Y%m%d')

# Unpack the OS .ISO, inject the files, and pack it again
#   Inject following files:
#     1. hpe-preseed_setup.cfg
mkdir -p /media/debian/
mkdir -p /tmp/custom_iso
ls -lrt $INPUT_ISO_FILENAME
md5sum $INPUT_ISO_FILENAME
sudo mount -t iso9660 -o loop $INPUT_ISO_FILENAME /media/debian/
cd /media/debian/
tar cf - . | (cd /tmp/custom_iso; tar xfp -)
ls -lrt /tmp/custom_iso/
cd -
sudo cp hpe-preseed_setup.cfg /tmp/custom_iso/
sudo umount /media/debian/
xorriso -as mkisofs -isohybrid-mbr /usr/lib/ISOLINUX/isohdpfx.bin \
  -c isolinux/boot.cat -b isolinux/isolinux.bin -no-emul-boot -boot-load-size 4 \
  -boot-info-table -eltorito-alt-boot -e boot/grub/efi.img -no-emul-boot \
  -isohybrid-gpt-basdat -o $INPUT_ISO_FILENAME /tmp/custom_iso/
ls -lrt $INPUT_ISO_FILENAME
md5sum $INPUT_ISO_FILENAME
sudo rm -rf /tmp/custom_iso/

# Locate the GRUB Configuration File
UEFI_CFG_FILE=boot/grub/grub.cfg  # For Debian

xorriso -osirrox on -indev $INPUT_ISO_FILENAME -extract ${UEFI_CFG_FILE} ${UEFI_CFG_FILE}

if [ ! -f "${UEFI_CFG_FILE}" ]; then
  echo "did not find ${UEFI_CFG_FILE} on <sles-iso-filename>"
  exit -1
fi

# Make the extracted file writable (xorriso makes it read-only when extracted)
chmod -R u+w boot # for Debian based OS

# The clean function cleans up any lingering files
# that might be present when the script exits.
clean() {
  # remove entire $UEFI_CFG_FILE directory & files
  if [ -d "boot" ]; then
     rm -rf boot
  fi
}

trap clean EXIT

if [ ! -f "${UEFI_CFG_FILE}" ]; then
  echo "did not find ${UEFI_CFG_FILE} on <debian-iso-filename>"
  exit -1
fi

# save the original grub.cfg files
UEFI_ORIG_CFG_FILE=$(mktemp /tmp/grub.cfg.XXXXXXXXX)
cp ${UEFI_CFG_FILE} $UEFI_ORIG_CFG_FILE

echo "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"
echo $UEFI_ORIG_CFG_FILE
cat $UEFI_ORIG_CFG_FILE
echo "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"

###################################################
# start the UEFI_CFG_FILE file modifications

# set the the default timeout to 0 seconds
sed -i '1itimeout=0' ${UEFI_CFG_FILE}

# change the menu selection to the 1st entry
sed -i '2iprompt=1' ${UEFI_CFG_FILE}

# tell the .ISO to run the hpe-preseed_setup.cfg as the
# thing that kickstarts the automated install
# also setup the serial console to ttyS1 (iLO serial port) with 115200 baud
sed -i -E "s/(.*)(\/vmlinuz)(.*)/\1\2 auto=true preseed\/file=\/cdrom\/hpe-preseed_setup.cfg console=ttyS1,115200 priority=critical BOOT_DEBUG=2 \3/" ${UEFI_CFG_FILE}

# remove the 'quiet' option so the user can watch kernel loading
# and use to triage any problems
sed -i "s/quiet//" ${UEFI_CFG_FILE}

# report on the changes to isolinux.org
echo "===================================================="
echo diff -u $UEFI_ORIG_CFG_FILE ${UEFI_CFG_FILE}
set +e
diff -u $UEFI_ORIG_CFG_FILE ${UEFI_CFG_FILE}
set -e
echo "===================================================="

echo "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"
echo $UEFI_CFG_FILE
cat $UEFI_CFG_FILE
echo "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"

# end the UEFI_CFG_FILE file modifications
###################################################

# Create the Debian .ISO file

echo
echo Creating ${CUSTOM_ISO_FILENAME}

# Create new ISO file with modified CFG
xorriso -indev $INPUT_ISO_FILENAME -outdev ${CUSTOM_ISO_FILENAME} -boot_image isohybrid keep -update ${UEFI_CFG_FILE} ${UEFI_CFG_FILE}

# Implant an MD5 checksum into the image. Without performing this step,
# image verification check (the rd.live.check option in the boot
# loader configuration) will fail and you will not be able to continue
# with the installation.
MD5_ISO="implantisomd5 ${CUSTOM_ISO_FILENAME}"
echo $MD5_ISO
$MD5_ISO