#!/bin/bash
set -eo pipefail

help=$'Generate Tarball with PNOR image and MANIFEST Script

Generates a PNOR SquashFS image from the PNOR image for VPNOR,
Or use a static layout raw PNOR image,
Creates a MANIFEST for image verification and recreation
Packages the image and MANIFEST together in a tarball

usage: generate-tar [OPTION] <PNOR FILE>...

Options:
   -i, --image <squashfs|static>
                          Generate SquashFS image or use static PNOR
   -f, --file <file>      Specify destination file. Defaults to
                          $(pwd)/<PNOR FILE>.pnor.<image_type>.tar[.gz] if
                          unspecified.
                          (For example,
                          * "generate-tar -i squashfs my.pnor" would generate
                          $(pwd)/my.pnor.squashfs.tar
                          * "generate-tar -i static my.pnor" would generate
                          $(pwd)/my.pnor.static.tar.gz)
   -s, --sign <path>      Sign the image. The optional path argument specifies
                          the private key file. Defaults to the bash variable
                          PRIVATE_KEY_PATH if available, or else uses the
                          open-source private key in this script.
   -m, --machine <name>   Optionally specify the target machine name of this
                          image.
   -h, --help             Display this help text and exit.
'

private_key=$'-----BEGIN PRIVATE KEY-----
MIICdwIBADANBgkqhkiG9w0BAQEFAASCAmEwggJdAgEAAoGBAPvSDLu6slkP1gri
PaeQXL9ysD69J/HjbBCIQ0RPfeWBb75US1tRTjPP0Ub8CtH8ExVf8iF1ulsZA78B
zIjBYZVp9pyD6LbpZ/hjV7rIH6dTNhoVpdA+F8LzmQ7cyhHG8l2JMvdunwF2uX5k
D4WDcZt/ITKZNQNavPtmIyD5HprdAgMBAAECgYEAuQkTSi5ZNpAoWz76xtGRFSwU
zUT4wQi3Mz6tDtjKTYXasiQGa0dHC1M9F8fDu6BZ9W7W4Dc9hArRcdzEighuxoI/
nZI/0uL89iUEywnDEIHuS6D5JlZaj86/nx9YvQnO8F/seM+MX0EAWVrd5wC7aAF1
h6Fu7ykZB4ggUjQAWwECQQD+AUiDOEO+8btLJ135dQfSGc5VFcZiequnKWVm6uXt
rX771hEYjYMjLqWGFg9G4gE3GuABM5chMINuQQUivy8tAkEA/cxfy19XkjtqcMgE
x/UDt6Nr+Ky/tk+4Y65WxPRDas0uxFOPk/vEjgVmz1k/TAy9G4giisluTvtmltr5
DCLocQJBAJnRHx9PiD7uVhRJz6/L/iNuOzPtTsi+Loq5F83+O6T15qsM1CeBMsOw
cM5FN5UeMcwz+yjfHAsePMkcmMaU7jUCQHlg9+N8upXuIo7Dqj2zOU7nMmkgvSNE
5yuNImRZabC3ZolwaTdd7nf5r1y1Eyec5Ag5yENV6JKPe1Xkbb1XKJECQDngA0h4
6ATvfP1Vrx4CbP11eKXbCsZ9OGPHSgyvVjn68oY5ZP3uPsIattoN7dE2BRfuJm7m
F0nIdUAhR0yTfKM=
-----END PRIVATE KEY-----
'

# Reference the ffs structures at:
# https://github.com/open-power/hostboot/blob/master/src/usr/pnor/common/ffs_hb.H
# https://github.com/open-power/hostboot/blob/master/src/usr/pnor/ffs.h
ffs_entry_size=128
vercheck_offset=112
do_sign=false
PRIVATE_KEY_PATH=${PRIVATE_KEY_PATH:-}
private_key_path="${PRIVATE_KEY_PATH}"
image_type=""
outfile=""
declare -a partitions=()
tocfile="pnor.toc"
machine_name=""

while [[ $# -gt 0 ]]; do
  key="$1"
  case $key in
    -i|--image)
      image_type="$2"
      shift 2
      ;;
    -f|--file)
      outfile="$2"
      shift 2
      ;;
    -s|--sign)
      do_sign=true
      if [[ -n "${2}"  && "${2}" != -* ]]; then
        private_key_path="$2"
        shift 2
      else
        shift 1
      fi
      ;;
    -m|--machine)
      machine_name="$2"
      shift 2
      ;;
    -h|--help)
      echo "$help"
      exit
      ;;
    *)
      pnorfile="$1"
      shift 1
      ;;
  esac
done

if [ ! -f "${pnorfile}" ]; then
  echo "Please enter a valid PNOR file."
  echo "$help"
  exit 1
fi

if [[ "${image_type}" == "squashfs" ]]; then
  echo "Will generate squashfs image for VPNOR"
elif [[ "${image_type}" == "static" ]]; then
  echo "Will use static image for PNOR"
else
  echo "Please specify the image type, \"squashfs\" or \"static\""
  echo
  echo "$help"
  exit 1
fi

if [[ -z $outfile ]]; then
    if [[ ${pnorfile##*.} == "pnor" ]]; then
        outfile=$(pwd)/${pnorfile##*/}.$image_type.tar
    else
        outfile=$(pwd)/${pnorfile##*/}.pnor.$image_type.tar
    fi
    if [[ "${image_type}" == "static" ]]; then
        # Append .gz so the tarball is compressed
        outfile=$outfile.gz
    fi
else
    if [[ $outfile != /* ]]; then
        outfile=$(pwd)/$outfile
    fi
fi


scratch_dir=$(mktemp -d)
# Remove the temp directory on exit.
# The files in the temp directory may contain read-only files, so add
# --interactive=never to skip the prompt.
trap '{ rm -r --interactive=never ${scratch_dir}; }' EXIT

if [[ "${do_sign}" == true ]]; then
  if [[ -z "${private_key_path}" ]]; then
    private_key_path=${scratch_dir}/OpenBMC.priv
    echo "${private_key}" > "${private_key_path}"
    echo "Image is NOT secure!! Signing with the open private key!"
  else
    if [[ ! -f "${private_key_path}" ]]; then
      echo "Couldn't find private key ${private_key_path}."
      exit 1
    fi

    echo "Signing with ${private_key_path}."
  fi

  public_key_file=publickey
  public_key_path=${scratch_dir}/$public_key_file
  openssl pkey -in "${private_key_path}" -pubout -out "${public_key_path}"
fi

echo "Parsing PNOR TOC..."

pnor_dir="${scratch_dir}/pnor"
mkdir "${pnor_dir}"

pflash --partition=part --read="${pnor_dir}"/part -F "${pnorfile}"
pflash --partition=VERSION --read="${pnor_dir}"/VERSION -F "${pnorfile}"
version_size=$(wc -c "${pnor_dir}"/VERSION | cut -d' ' -f 1)
magic_number=$(xxd -p -l 4 "${pnor_dir}"/VERSION)
# Check if VERSION is signed. A signed version partition will have an extra
# 4K header starting with the magic number 0x17082011, see:
# https://github.com/open-power/skiboot/blob/master/libstb/container.h#L47
if [ "$version_size" == "8192" ] && [ "$magic_number" == "17082011" ]; then
  # Advance past the STB header (4K, indexed from 1)
  cp "${pnor_dir}"/VERSION "${pnor_dir}"/VERSION_FULL
  tail --bytes=+4097 "${pnor_dir}"/VERSION_FULL > "${pnor_dir}"/VERSION
fi
{
  version=$(head -n 1 "${pnor_dir}"/VERSION)
  echo "version=$version"
  # shellcheck disable=SC2005,SC2046 # Need the echo to remove new lines, same
  # reason for not quoting the tail command
  extended_version=$(echo $(tail -n +2 "${pnor_dir}"/VERSION)|tr ' ' ',')
  echo "extended_version=$extended_version"
  while read -r line; do
    if [[ $line == "ID="* ]]; then
        # This line looks like
        # "ID=05 MVPD 000d9000..00169000 (actual=00090000) [ECC]"
        read -r -a fields <<< "$line"

        id=${fields[0]##*=}
        offset=$((ffs_entry_size * 10#${id} + vercheck_offset))
        vercheck=$(xxd -p -l  0x1 -seek ${offset} "${pnor_dir}"/part)
        # shellcheck disable=SC2155 # Need the export in the same line to avoid
        # pflash error
        export flags=$(pflash --detail=$((10#$id)) -F "${pnorfile}" | grep "\[" |
                sed 's/....$//' | tr '\n' ',' | sed 's/.$//')
        if [[ $flags != "" ]]; then
            flags=,$flags
        fi

        if [[ $(echo "$flags" | grep "READONLY") == "" &&
              $(echo "$flags" | grep "PRESERVED") == "" ]]; then
            flags=$flags,READWRITE
        fi

        # Need the partition ID, name, start location, end location, and flags
        echo  "partition${id}=${fields[1]},${fields[2]/../,},${vercheck}${flags}"

        # Save the partition name
        partitions+=("${fields[1]}")
    fi
  # Don't need the BACKUP_PART partition
  done < <(pflash --info -F "${pnorfile}" | grep -v "BACKUP")
} > "${pnor_dir}"/${tocfile}

for partition in "${partitions[@]}"; do
  echo "Reading ${partition}..."
  pflash --partition="${partition}" \
    --read="${pnor_dir}"/"${partition}" \
    -F "${pnorfile}"
done

manifest_location="MANIFEST"
files_to_sign="$manifest_location $public_key_file"

# Go to scratch_dir

if [[ "${image_type}" == "squashfs" ]]; then
  echo "Creating SquashFS image..."
  # Prepare pnor file in ${pnor_dir}
  cd "${pnor_dir}"
  # Set permissions of partition files to read only
  chmod 440 -- *
  # shellcheck disable=SC2048,SC2086 # Do not quote partitions since it lists
  # multiple files and mksquashfs would assume to be a single file name within
  # quotes
  mksquashfs ${tocfile} ${partitions[*]} "${scratch_dir}"/pnor.xz.squashfs -all-root
  cd "${scratch_dir}"
  files_to_sign+=" pnor.xz.squashfs"
else
  cp "${pnorfile}" "${scratch_dir}"
  cd "${scratch_dir}"
  files_to_sign+=" $(basename "${pnorfile}")"
fi

echo "Creating MANIFEST for the image"
echo -e "purpose=xyz.openbmc_project.Software.Version.VersionPurpose.Host\nversion=$version\n\
extended_version=$extended_version" >> $manifest_location

if [[ -n "${machine_name}" ]]; then
    echo -e "MachineName=${machine_name}" >> $manifest_location
fi

if [[ "${do_sign}" == true ]]; then
  private_key_name=$(basename "${private_key_path}")
  key_type="${private_key_name%.*}"
  echo KeyType="${key_type}" >> $manifest_location
  echo HashType="RSA-SHA256" >> $manifest_location

  for file in $files_to_sign; do
    openssl dgst -sha256 -sign "${private_key_path}" -out "${file}.sig" "$file"
  done

  additional_files="*.sig"
fi

if [[ "${image_type}" == "squashfs" ]]; then
  echo "Generating tarball to contain the SquashFS image and its MANIFEST"
  # shellcheck disable=SC2086 # Do not quote the files variables since they list
  # multiple files and tar would assume to be a single file name within quotes
  tar -cvf "$outfile" $files_to_sign $additional_files
  echo "SquashFSTarball at ${outfile}"
else
  # shellcheck disable=SC2086 # Do not quote the files variables since they list
  # multiple files and tar would assume to be a single file name within quotes
  tar -czvf "$outfile" $files_to_sign $additional_files
  echo "Static layout tarball at $outfile"
fi