#!/bin/bash

#

# grubby wrapper to manage BootLoaderSpec files

#

#

# Copyright 2018 Red Hat, Inc.  All rights reserved.

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program.  If not, see <http://www.gnu.org/licenses/>.

readonly SCRIPTNAME="${0##*/}"

CMDLINE_LINUX_DEBUG=" systemd.log_level=debug systemd.log_target=kmsg"

LINUX_DEBUG_VERSION_POSTFIX="_with_debugging"

LINUX_DEBUG_TITLE_POSTFIX=" with debugging"

declare -a bls_file

declare -a bls_title

declare -a bls_version

declare -a bls_linux

declare -a bls_initrd

declare -a bls_options

declare -a bls_id

[[ -f /etc/sysconfig/kernel ]] && . /etc/sysconfig/kernel

[[ -f /etc/os-release ]] && . /etc/os-release

read MACHINE_ID < /etc/machine-id

arch=$(uname -m)

if [[ $arch = 's390' || $arch = 's390x' ]]; then

    bootloader="zipl"

else

    bootloader="grub2"

fi

print_error() {

    echo "$1" >&2

    exit 1

}

print_info() {

    echo "$1" >&2

}

if [[ ${#} = 0 ]]; then

    print_error "no action specified"

fi

get_bls_value() {

    local bls="$1" && shift

    local key="$1" && shift

    echo "$(grep "^${key}[ \t]" "${bls}" | sed -e "s!^${key}[ \t]*!!")"

}

set_bls_value() {

    local bls="$1" && shift

    local key="$1" && shift

    local value="$1" && shift

    value=$(echo $value | sed -e 's/\//\\\//g')

    sed -i -e "s/^${key}.*/${key} ${value}/" "${bls}"

}

append_bls_value() {

    local bls="$1" && shift

    local key="$1" && shift

    local value="$1" && shift

    old_value="$(get_bls_value "${bls}" ${key})"

    set_bls_value "${bls}" "${key}" "${old_value}${value}"

}

get_bls_values() {

    count=0

    local -a files

    local IFS=$'\n'

    files=($(for bls in ${blsdir}/*.conf ; do

        if ! [[ -e "${bls}" ]] ; then

            continue

        fi

        bls="${bls%.conf}"

        bls="${bls##*/}"

        echo "${bls}"

    done | /usr/libexec/grubby/rpm-sort -c rpmnvrcmp | tac)) || :

    for bls in "${files[@]}" ; do

        blspath="${blsdir}/${bls}.conf"

        bls_file[$count]="${blspath}"

        bls_title[$count]="$(get_bls_value ${blspath} title)"

        bls_version[$count]="$(get_bls_value ${blspath} version)"

        bls_linux[$count]="$(get_bls_value ${blspath} linux)"

        bls_initrd[$count]="$(get_bls_value ${blspath} initrd)"

        bls_options[$count]="$(get_bls_value ${blspath} options)"

        bls_id[$count]="${bls}"

        count=$((count+1))

    done

}

get_default_index() {

    local default=""

    local index="-1"

    local title=""

    local version=""

    if [[ $bootloader = "grub2" ]]; then

	default="$(grep '^saved_entry=' ${env} | sed -e 's/^saved_entry=//')"

    else

	default="$(grep '^default=' ${zipl_config} | sed -e 's/^default=//')"

    fi

    if [[ -z $default ]]; then

	index=0

    elif [[ $default =~ ^[0-9]+$ ]]; then

	index="$default"

    fi

    for i in ${!bls_file[@]}; do

        if [[ $i -eq $index ]]; then

            echo $i

            return

        fi

        if [[ $default = ${bls_id[$i]} || $default = ${bls_title[$i]} ]]; then

            echo $i

            return

        fi

    done

}

display_default_value() {

    local prefix=$(get_prefix)

    case "$display_default" in

        kernel)

            echo "${prefix}${bls_linux[$default_index]}"

            exit 0

            ;;

        index)

            echo "$default_index"

            exit 0

            ;;

        title)

            echo "${bls_title[$default_index]}"

            exit 0

            ;;

    esac

}

param_to_indexes() {

    local param="$1"

    local indexes=""

    if [[ $param = "ALL" ]]; then

        for i in ${!bls_file[@]}; do

            indexes="$indexes $i"

        done

        echo -n $indexes

        return

    fi

    if [[ $param = "DEFAULT" ]]; then

        echo -n $default_index

        return

    fi

    for i in ${!bls_file[@]}; do

        if [[ $param = "${bls_linux[$i]}" || "/${param##*/}" = "${bls_linux[$i]}" ]]; then

            indexes="$indexes $i"

        fi

        if [[ $param = "TITLE=${bls_title[$i]}" ]]; then

            indexes="$indexes $i"

        fi

	if [[ $param = $i ]]; then

	    indexes="$indexes $i"

	fi

    done

    if [[ -n $indexes ]]; then

        echo -n $indexes

        return

    fi

    echo -n "-1"

}

get_prefix() {

    if [[ $bootloader = grub2 ]] && grep -q /boot /proc/mounts; then

	echo "/boot"

    else

	echo ""

    fi

}

expand_var() {

    local var=$1

    if [[ $bootloader == "grub2" ]]; then

        local value="$(grub2-editenv "${env}" list | grep ${var##$} | sed -e "s/${var##$}=//")"

        value="$(echo ${value} | sed -e 's/\//\\\//g')"

        if [[ -n $value ]]; then

            var="$value"

        fi

    fi

    echo $var

}

get_bls_args() {

    local args=${bls_options[$i]}

    local opts=(${args})

    for opt in ${opts[*]}; do

        if [[ $opt =~ ^\$ ]]; then

            value="$(expand_var $opt)"

            args="$(echo ${args} | sed -e "s/${opt}/${value}/")"

        fi

    done

    echo ${args}

}

display_info_values() {

    local indexes=($(param_to_indexes "$1"))

    local prefix=$(get_prefix)

    if [[ $indexes = "-1" ]]; then

        print_error "The param $1 is incorrect"

    fi

    for i in ${indexes[*]}; do

        local root=""

        local value=""

        local args="$(get_bls_args "$i")"

        local opts=(${args})

        for opt in ${opts[*]}; do

            if echo $opt | grep -q "^root="; then

                root="$(echo $opt | sed -e 's/root=//')"

                value="$(echo ${opt} | sed -e 's/\//\\\//g')"

                args="$(echo ${args} | sed -e "s/${value}[ \t]*//")"

                break

            fi

        done

        echo "index=$i"

        echo "kernel=\"${prefix}${bls_linux[$i]}\""

        echo "args=\"${args}\""

        if [[ -n $root ]]; then

            echo "root=\"${root}\""

        fi

        echo "initrd=\"${prefix}${bls_initrd[$i]}\""

        echo "title=\"${bls_title[$i]}\""

        echo "id=\"${bls_id[$i]}\""

    done

    exit 0

}

mkbls() {

    local kernel=$1 && shift

    local kernelver=$1 && shift

    local datetime=$1 && shift

    local debugname=""

    local flavor=""

    local prefix=""

    if [[ $(get_prefix) = "" ]]; then

	prefix="/boot"

    fi

    if [[ $kernelver == *\+* ]] ; then

        local flavor=-"${kernelver##*+}"

        if [[ $flavor == "-debug" ]]; then

            local debugname="with debugging"

	    local debugid="-debug"

        fi

    fi

    cat <

title ${NAME} (${kernelver}) ${VERSION}${debugname}

version ${kernelver}${debugid}

linux ${kernel}

initrd ${prefix}/initramfs-${kernelver}.img

options \$kernelopts

id ${ID}-${datetime}-${kernelver}${debugid}

grub_users \$grub_users

grub_arg --unrestricted

grub_class kernel${flavor}

EOF

}

remove_bls_fragment() {

    local indexes=($(param_to_indexes "$1"))

    if [[ $indexes = "-1" ]]; then

	print_error "The param $1 is incorrect"

    fi

    for i in "${indexes[@]}"; do

        rm -f "${bls_file[$i]}"

    done

    get_bls_values

    update_grubcfg

}

get_custom_bls_filename() {

    local kernelver=$1

    local bls_target="${blsdir}/${MACHINE_ID}-${kernelver}.conf"

    count=0

    local -a files

    local IFS=$'\n'

    prefix="${bls_target%%.conf}"

    prefix="${bls_target%%${arch}}"

    prefix="${prefix%.*}"

    last=($(for bls in ${prefix}.*~custom*.conf ; do

        if ! [[ -e "${bls}" ]] ; then

            continue

        fi

        bls="${bls##${prefix}.}"

        bls="${bls%%~custom*}"

        echo "${bls}"

    done | tail -n1)) || :

    if [[ -z $last ]]; then

        last="0"

    else

        last=$((last+1))

    fi

    echo "${bls_target}" | sed -e "s!${prefix}!${prefix}.${last}~custom!"

}

add_bls_fragment() {

    local kernel="$1" && shift

    local title="$1" && shift

    local options="$1" && shift

    local initrd="$1" && shift

    local extra_initrd="$1" && shift

    if [[ $kernel = *"vmlinuz-"* ]]; then

	kernelver="${kernel##*/vmlinuz-}"

	prefix="vmlinuz-"

    else

	kernelver="${kernel##*/}"

    fi

    if [[ ! -f "/boot/${prefix}${kernelver}" ]] &&

       [[ $bad_image != "true" ]]; then

        print_error "The ${kernelver} kernel isn't installed in the machine"

    fi

    if [[ -z $title ]]; then

	print_error "The kernel title must be specified"

    fi

    if [[ ! -d $blsdir ]]; then

        install -m 700 -d "${blsdir}"

    fi

    bls_target="${blsdir}/${MACHINE_ID}-${kernelver}.conf"

    if [[ -e ${bls_target} ]]; then

        bls_target="$(get_custom_bls_filename "${kernelver}")"

        print_info "An entry for kernel ${kernelver} already exists, adding ${bls_target}"

    fi

    kernel_dir="/lib/modules/${kernelver}"

    if [[ -d $kernel_dir ]]; then

        datetime="$(date -u +%Y%m%d%H%M%S -d "$(stat -c '%y' "${kernel_dir}")")"

    else

        datetime=0

    fi

    mkbls "${kernel}" "${kernelver}" "${datetime}" > "${bls_target}"

    if [[ -n $title ]]; then

        set_bls_value "${bls_target}" "title" "${title}"

    fi

    if [[ -n $options ]]; then

        set_bls_value "${bls_target}" "options" "${options}"

    fi

    if [[ -n $initrd ]]; then

        set_bls_value "${bls_target}" "initrd" "${initrd}"

    fi

    if [[ -n $extra_initrd ]]; then

        append_bls_value "${bls_target}" "initrd" "${extra_initrd}"

    fi

    if [[ $MAKEDEBUG = "yes" ]]; then

        bls_debug="$(echo ${bls_target} | sed -e "s/${kernelver}/${kernelver}~debug/")"

        cp -aT  "${bls_target}" "${bls_debug}"

        append_bls_value "${bls_debug}" "title" "${LINUX_DEBUG_TITLE_POSTFIX}"

        append_bls_value "${bls_debug}" "version" "${LINUX_DEBUG_VERSION_POSTFIX}"

        append_bls_value "${bls_debug}" "options" "${CMDLINE_LINUX_DEBUG}"

        blsid="$(get_bls_value ${bls_debug} "id" | sed -e "s/${kernelver}/${kernelver}~debug/")"

        set_bls_value "${bls_debug}" "id" "${blsid}"

    fi

    get_bls_values

    if [[ $make_default = "true" ]]; then

        set_default_bls "TITLE=${title}"

    fi

    update_grubcfg

    exit 0

}

update_args() {

    local args=$1 && shift

    local remove_args=($1) && shift

    local add_args=($1) && shift

    for arg in ${remove_args[*]}; do

        if [[ $arg = *"="* ]]; then

            arg=$(echo $arg | sed -e 's/\//\\\//g')

            args="$(echo $args | sed -E "s/(^|[[:space:]])$arg([[:space:]]|$)/ /")"

        else

            args="$(echo $args | sed -E "s/(^|[[:space:]])$arg(([[:space:]]|$)|([=][^ ]*([$]*)))/ /g")"

        fi

    done

    for arg in ${add_args[*]}; do

        arg=${arg%=*}

        args="$(echo $args | sed -E "s/(^|[[:space:]])$arg(([[:space:]]|$)|([=][^ ]*([$]*)))/ /g")"

    done

    for arg in ${add_args[*]}; do

        args="$args $arg"

    done

    echo ${args}

}

update_bls_fragment() {

    local indexes=($(param_to_indexes "$1")) && shift

    local remove_args=$1 && shift

    local add_args=$1 && shift

    local initrd=$1 && shift

    if [[ $indexes = "-1" ]]; then

        print_error "The param $1 is incorrect"

    fi

    for i in ${indexes[*]}; do

	if [[ -n $remove_args || -n $add_args ]]; then

            local old_args="$(get_bls_args "$i")"

            local new_args="$(update_args "${old_args}" "${remove_args}" "${add_args}")"

            set_bls_value "${bls_file[$i]}" "options" "${new_args}"

	fi

	if [[ -n $initrd ]]; then

	    set_bls_value "${bls_file[$i]}" "initrd" "${initrd}"

	fi

    done

    update_grubcfg

}

set_default_bls() {

    local index=($(param_to_indexes "$1"))

    if [[ $index = "-1" ]]; then

        print_error "The param $1 is incorrect"

    fi

    if [[ $bootloader = grub2 ]]; then

        grub2-editenv "${env}" set saved_entry="${bls_id[$index]}"

    else

        local default="${bls_title[$index]}"

        local current="$(grep '^default=' ${zipl_config} | sed -e 's/^default=//')"

        if [[ -n $current ]]; then

            sed -i -e "s,^default=.*,default=${default}," "${zipl_config}"

        else

            echo "default=${default}" >> "${zipl_config}"

        fi

    fi

    print_info "The default is ${bls_file[$index]} with index $index and kernel $(get_prefix)${bls_linux[$index]}"

}

remove_var_prefix() {

    if [[ -n $remove_kernel && $remove_kernel =~ ^/ ]]; then

       remove_kernel="/${remove_kernel##*/}"

    fi

    if [[ -n $initrd ]]; then

	initrd="/${initrd##*/}"

    fi

    if [[ -n $extra_initrd ]]; then

	extra_initrd=" /${extra_initrd##*/}"

    fi

    if [[ -n $kernel ]]; then

	kernel="/${kernel##*/}"

    fi

    if [[ -n $update_kernel && $update_kernel =~ ^/ ]]; then

	update_kernel="/${update_kernel##*/}"

    fi

}

update_grubcfg()

{

    if [[ $arch = 'ppc64' || $arch = 'ppc64le' ]]; then

	grub2-mkconfig -o /boot/grub2/grub.cfg >& /dev/null

    fi

}

print_usage()

{

    cat <

Usage: grubby [OPTION...]

      --add-kernel=kernel-path            add an entry for the specified kernel

      --args=args                         default arguments for the new kernel or new arguments for kernel being updated)

      --bad-image-okay                    don't sanity check images in boot entries (for testing only)

  -c, --config-file=path                  path to grub config file to update ("-" for stdin)

      --copy-default                      use the default boot entry as a template for the new entry being added; if the default is not a linux image, or if the kernel referenced by the default image does not exist, the

                                          first linux entry whose kernel does exist is used as the template

      --default-kernel                    display the path of the default kernel

      --default-index                     display the index of the default kernel

      --default-title                     display the title of the default kernel

      --env=path                          path for environment data

      --grub2                             configure grub2 bootloader

      --info=kernel-path                  display boot information for specified kernel

      --initrd=initrd-path                initrd image for the new kernel

  -i, --extra-initrd=initrd-path          auxiliary initrd image for things other than the new kernel

      --make-default                      make the newly added entry the default boot entry

  -o, --output-file=path                  path to output updated config file ("-" for stdout)

      --remove-args=STRING                remove kernel arguments

      --remove-kernel=kernel-path         remove all entries for the specified kernel

      --set-default=kernel-path           make the first entry referencing the specified kernel the default

      --set-default-index=entry-index     make the given entry index the default entry

      --title=entry-title                 title to use for the new kernel entry

      --update-kernel=kernel-path         updated information for the specified kernel

      --zipl                              configure zipl bootloader

  -b, --bls-directory                     path to directory containing the BootLoaderSpec fragment files

Help options:

  -?, --help                              Show this help message

EOF

}

OPTS="$(getopt -o c:i:o:b:? --long help,add-kernel:,args:,bad-image-okay,\

config-file:,copy-default,default-kernel,default-index,default-title,env:,\

grub2,info:,initrd:,extra-initrd:,make-default,output-file:,remove-args:,\

remove-kernel:,set-default:,set-default-index:,title:,update-kernel:,zipl,\

bls-directory:,add-kernel:,add-multiboot:,mbargs:,mounts:,boot-filesystem:,\

bootloader-probe,debug,devtree,devtreedir:,elilo,efi,extlinux,grub,lilo,\

output-file:,remove-mbargs:,remove-multiboot:,silo,yaboot -n ${SCRIPTNAME} -- "$@")"

[[ $? = 0 ]] || exit 1

eval set -- "$OPTS"

while [ ${#} -gt 0 ]; do

    case "$1" in

        --help|-h)

            print_usage

            exit 0

            ;;

        --add-kernel)

            kernel="${2}"

            shift

            ;;

        --args)

            args="${2}"

            shift

            ;;

        --bad-image-okay)

            bad_image=true

            ;;

        --config-file|-c)

            zipl_config="${2}"

            shift

            ;;

        --copy-default)

            copy_default=true

            ;;

        --default-kernel)

            display_default="kernel"

            ;;

        --default-index)

            display_default="index"

            ;;

        --default-title)

            display_default="title"

            ;;

        --env)

            env="${2}"

            shift

            ;;

        --grub2)

            bootloader="grub2"

            ;;

        --info)

            display_info="${2}"

            shift

            ;;

        --initrd)

            initrd="${2}"

            shift

            ;;

        --extra-initrd|-i)

            extra_initrd=" /${2}"

            shift

            ;;

        --make-default)

            make_default=true

            ;;

        --output-file|-o)

            output_file="${2}"

            shift

            ;;

        --remove-args)

            remove_args="${2}"

            shift

            ;;

        --remove-kernel)

            remove_kernel="${2}"

            shift

            ;;

        --set-default)

            set_default="${2}"

            shift

            ;;

        --set-default-index)

            set_default="${2}"

            shift

            ;;

        --title)

            title="${2}"

            shift

            ;;

        --update-kernel)

            update_kernel="${2}"

            shift

            ;;

        --zipl)

            bootloader="zipl"

            ;;

        --bls-directory|-b)

            blsdir="${2}"

	    shift

	    ;;

        --add-kernel|--add-multiboot|--mbargs|--mounts|--boot-filesystem|\

        --bootloader-probe|--debug|--devtree|--devtreedir|--elilo|--efi|\

        --extlinux|--grub|--lilo|--output-file|--remove-mbargs|--silo|\

        --remove-multiboot|--slilo|--yaboot)

            echo

            echo "${SCRIPTNAME}: the option \"${1}\" was deprecated" >&2

            echo "Try '${SCRIPTNAME} --help' to list supported options" >&2

            echo

	    exit 1

	    ;;

        --)

            shift

            break

            ;;

        *)

            echo

            echo "${SCRIPTNAME}: invalid option \"${1}\"" >&2

            echo "Try '${SCRIPTNAME} --help' for more information" >&2

            echo

            exit 1

            ;;

    esac

    shift

done

if [[ -z $blsdir ]]; then

    blsdir="/boot/loader/entries"

fi

if [[ -z $env ]]; then

    env="/boot/grub2/grubenv"

fi

if [[ -z $zipl_config ]]; then

    zipl_config="/etc/zipl.conf"

fi

get_bls_values

default_index="$(get_default_index)"

if [[ -n $display_default ]]; then

    display_default_value

fi

if [[ -n $display_info ]]; then

    display_info_values "${display_info}"

fi