initrd/mkinitrd.sh

   1 #!/bin/sh
   2 #
   3 # Copyright (c) 2010, 2018
   4 #       The DragonFly Project.  All rights reserved.
   5 #
   6 # Redistribution and use in source and binary forms, with or without
   7 # modification, are permitted provided that the following conditions
   8 # are met:
   9 #
  10 # 1. Redistributions of source code must retain the above copyright
  11 #    notice, this list of conditions and the following disclaimer.
  12 # 2. Redistributions in binary form must reproduce the above copyright
  13 #    notice, this list of conditions and the following disclaimer in
  14 #    the documentation and/or other materials provided with the
  15 #    distribution.
  16 # 3. Neither the name of The DragonFly Project nor the names of its
  17 #    contributors may be used to endorse or promote products derived
  18 #    from this software without specific, prior written permission.
  19 #
  20 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21 # ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22 # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  23 # FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  24 # COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  25 # INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  26 # BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  27 # LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  28 # AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  29 # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  30 # OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31 # SUCH DAMAGE.
  32 #
  33
  34 #
  35 # Description
  36 #
  37 # This tool packs the (statically linked) rescue tools (at /rescue by
  38 # default) and contents specified by "-c <content_dirs>", such as the
  39 # necessary etc files, into an UFS-formatted image.  This image is
  40 # installed at /boot/kernel/initrd.img.gz and used as the initial ramdisk
  41 # to help mount the real root filesystem when it is encrypted or on LVM.
  42 #
  43
  44
  45 #
  46 # Default configurations
  47 #
  48
  49 # Directory hierarchy on the initrd
  50 #
  51 # * 'new_root' will always be created
  52 # * 'sbin', 'usr.bin', and 'usr.sbin' will be symlinked to 'bin'
  53 # * 'tmp' will be symlinked to 'var/tmp'
  54 #
  55 INITRD_DIRS="bin dev etc mnt usr var"
  56
  57 # Directory of the statically linked rescue tools which will be copied
  58 # onto the initrd.
  59 RESCUE_DIR="/rescue"
  60
  61 # Specify the location that the initrd will be installed to, i.e.,
  62 # <BOOT_DIR>/kernel/initrd.img.gz
  63 BOOT_DIR="/boot"
  64
  65 # Maximum size (number of MB) allowed for the initrd image
  66 INITRD_SIZE_MAX="15"  # MB
  67
  68 # When run from the buildworld/installworld environment do not require that
  69 # things like uniq, kldload, mount, newfs, etc be in the cross-tools.
  70 # These must run natively for the current system version.
  71 #
  72 PATH=${PATH}:/sbin:/usr/sbin:/bin:/usr/bin
  73
  74 #
  75 # Helper functions
  76 #
  77
  78 log() {
  79         echo "$@" >&2
  80 }
  81
  82 error() {
  83         local rc=$1
  84         shift
  85         log "$@"
  86         exit ${rc}
  87 }
  88
  89 check_dirs() {
  90         for _dir; do
  91                 [ -d "${_dir}" ] ||
  92                     error 1 "Directory '${_dir}' does not exist"
  93         done
  94         return 0
  95 }
  96
  97
  98 #
  99 # Functions
 100 #
 101
 102 calc_initrd_size() {
 103         log "Calculating required initrd size ..."
 104         isize=0
 105         for _dir; do
 106                 csize=$(du -kst ${_dir} | awk '{ print $1 }')  # KB
 107                 log "* ${_dir}: ${csize} KB"
 108                 isize=$((${isize} + ${csize}))
 109         done
 110         # Round initrd size up by MB
 111         isize_mb=$(echo ${isize} | awk '
 112             function ceil(x) {
 113                 y = int(x);
 114                 return (x>y ? y+1 : y);
 115             }
 116             {
 117                 print ceil($1 / 1024);
 118             }')
 119         # Reserve another 1 MB for advanced user to add custom files to the
 120         # initrd without creating it from scratch.
 121         echo $((${isize_mb} + 1))
 122 }
 123
 124 make_img() {
 125         makefs -m ${INITRD_SIZE}m -M ${INITRD_SIZE}m -t ffs -o density=131072 \
 126             -o minfree=0 ${INITRD_FILE} ${BUILD_DIR}
 127 }
 128
 129 make_hier() {
 130         mkdir -p ${BUILD_DIR}/new_root ||
 131             error 1 "Failed to mkdir ${BUILD_DIR}/new_root"
 132         # Symlink 'sbin' to 'bin'
 133         ln -sf bin ${BUILD_DIR}/sbin
 134         # Symlink 'tmp' to 'var/tmp', as '/var' will be mounted with
 135         # tmpfs, saving a second tmpfs been mounted on '/tmp'.
 136         ln -sf var/tmp ${BUILD_DIR}/tmp
 137         for _dir in ${INITRD_DIRS}; do
 138                 [ ! -d "${BUILD_DIR}/${_dir}" ] &&
 139                     mkdir -p ${BUILD_DIR}/${_dir}
 140         done
 141         # Symlink 'usr/bin' and 'usr/sbin' to 'bin'
 142         ln -sf ../bin ${BUILD_DIR}/usr/bin
 143         ln -sf ../bin ${BUILD_DIR}/usr/sbin
 144         echo "Created directory structure"
 145 }
 146
 147 copy_rescue() {
 148         cpdup -o -u ${RESCUE_DIR}/ ${BUILD_DIR}/bin/ &&
 149             echo "Copied ${RESCUE_DIR} to ${BUILD_DIR}/bin" ||
 150             error 1 "Failed to copy ${RESCUE_DIR} to ${BUILD_DIR}/bin"
 151 }
 152
 153 copy_content() {
 154         for _dir in ${CONTENT_DIRS}; do
 155                 cpdup -o -u ${_dir}/ ${BUILD_DIR}/ &&
 156                     echo "Copied ${_dir} to ${BUILD_DIR}" ||
 157                     error 1 "Failed to copy ${dir} to ${BUILD_DIR}"
 158         done
 159 }
 160
 161 print_info() {
 162         lt ${BUILD_DIR}
 163 }
 164
 165 # Check the validity of the created initrd image before moving over.
 166 # This prevents creating an empty and broken initrd image by running
 167 # this tool but without ${CONTENT_DIRS} prepared.
 168 #
 169 # NOTE: Need more improvements.
 170 #
 171 check_initrd()
 172 {
 173         [ -x "${BUILD_DIR}/sbin/oinit" ] &&
 174         [ -x "${BUILD_DIR}/bin/sh" ] &&
 175         [ -x "${BUILD_DIR}/etc/rc" ] || {
 176                 error 1 "Invalid initrd image!"
 177         }
 178 }
 179
 180 usage() {
 181         error 2 \
 182             "usage: ${0##*/} [-b boot_dir] [-r rescue_dir]" \
 183             "[-s size] [-S max_size] -c <content_dirs>"
 184 }
 185
 186
 187 #
 188 # Main
 189 #
 190
 191 while getopts :b:c:hr:s:S: opt; do
 192         case ${opt} in
 193         b)
 194                 BOOT_DIR="${OPTARG}"
 195                 ;;
 196         c)
 197                 CONTENT_DIRS="${OPTARG}"
 198                 ;;
 199         h)
 200                 usage
 201                 ;;
 202         r)
 203                 RESCUE_DIR="${OPTARG}"
 204                 ;;
 205         s)
 206                 INITRD_SIZE="${OPTARG}"
 207                 ;;
 208         S)
 209                 INITRD_SIZE_MAX="${OPTARG}"
 210                 ;;
 211         \?)
 212                 log "Invalid option -${OPTARG}"
 213                 usage
 214                 ;;
 215         :)
 216                 log "Option -${OPTARG} requires an argument"
 217                 usage
 218                 ;;
 219         esac
 220 done
 221
 222 shift $((OPTIND - 1))
 223 [ $# -ne 0 ] && usage
 224 [ -z "${BOOT_DIR}" -o -z "${RESCUE_DIR}" -o -z "${CONTENT_DIRS}" ] && usage
 225 check_dirs ${BOOT_DIR} ${RESCUE_DIR} ${CONTENT_DIRS}
 226
 227 INITRD_SIZE=${INITRD_SIZE%[mM]}  # MB
 228 INITRD_SIZE_MAX=${INITRD_SIZE_MAX%[mM]}  # MB
 229
 230 BUILD_DIR=$(mktemp -d -t initrd) || error $? "Cannot create build directory"
 231 echo "Initrd build directory: ${BUILD_DIR}"
 232 INITRD_FILE="${BUILD_DIR}.img"
 233 INITRD_DEST="${BOOT_DIR}/kernel/initrd.img.gz"
 234
 235 CSIZE=$(calc_initrd_size ${RESCUE_DIR} ${CONTENT_DIRS})
 236 echo "Required initrd image size: ${CSIZE} MB"
 237 if [ -n "${INITRD_SIZE}" -a "${INITRD_SIZE}" != "0" ]; then
 238         if [ ${CSIZE} -gt ${INITRD_SIZE} ]; then
 239                 error 1 "Given initrd size (${INITRD_SIZE} MB) too small"
 240         fi
 241 else
 242         INITRD_SIZE=${CSIZE}
 243 fi
 244 echo "Initrd size: ${INITRD_SIZE} MB"
 245
 246 if [ -n "${INITRD_SIZE_MAX}" -a "${INITRD_SIZE_MAX}" != "0" ] && \
 247    [ ${INITRD_SIZE} -gt ${INITRD_SIZE_MAX} ]; then
 248         error 1 "Exceeded the maximum size (${INITRD_SIZE_MAX} MB)"
 249 fi
 250
 251 make_hier
 252 copy_rescue
 253 copy_content
 254 print_info
 255 make_img
 256 rm -rf ${BUILD_DIR}
 257
 258 echo -n "Compressing ${INITRD_FILE} ..."
 259 gzip -9 ${INITRD_FILE}
 260 echo " OK"
 261
 262 if [ -f "${INITRD_DEST}" ]; then
 263         echo -n "Backing up ${INITRD_DEST} ..."
 264         mv ${INITRD_DEST} ${INITRD_DEST}.old
 265         echo " OK (${INITRD_DEST}.old)"
 266 fi
 267
 268 echo -n "Installing ${INITRD_FILE}.gz to ${INITRD_DEST} ..."
 269 install -o root -g wheel -m 444 ${INITRD_FILE}.gz ${INITRD_DEST}
 270 echo " OK"
 271 rm -f ${INITRD_FILE}.gz