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 VN 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' will be symlinked to 'bin'
  53 # * 'tmp' will be symlinked to 'var/tmp'
  54 #
  55 INITRD_DIRS="bin dev etc mnt 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 # Calculate the total size of the given directory, taking care of the
  98 # hard links.
  99 #
 100 # NOTE: Do not use 'du' since it gives the disk usage of the files,
 101 #       which varies between different filesystems.
 102 #
 103 calc_size() {
 104         find "$1" -ls | \
 105             awk '{ print $7,$1 }' | \
 106             sort -n -k 2 | \
 107             uniq -f 1 | \
 108             awk '{ sum+=$1 } END { print sum }'  # byte
 109 }
 110
 111
 112 #
 113 # Functions
 114 #
 115
 116 calc_initrd_size() {
 117         log "Calculating required initrd size ..."
 118         isize=0
 119         for _dir; do
 120                 csize=$(calc_size ${_dir})
 121                 log "* ${_dir}: ${csize} bytes"
 122                 isize=$((${isize} + ${csize}))
 123         done
 124         # Round initrd size up by MB
 125         isize_mb=$(echo ${isize} | awk '
 126             function ceil(x) {
 127                 y = int(x);
 128                 return (x>y ? y+1 : y);
 129             }
 130             {
 131                 mb = $1/1024/1024;
 132                 print ceil(mb);
 133             }')
 134         # Reserve another 1 MB for advanced user to add custom files to the
 135         # initrd without creating it from scratch.
 136         echo $((${isize_mb} + 1))
 137 }
 138
 139 create_vn() {
 140         kldstat -qm vn || kldload -n vn ||
 141             error 1 "Failed to load vn kernel module"
 142
 143         VN_DEV=$(vnconfig -c -S ${INITRD_SIZE}m -Z -T vn ${INITRD_FILE}) &&
 144             echo "Configured ${VN_DEV}" ||
 145             error 1 "Failed to configure VN device"
 146
 147         newfs -i 131072 -m 0 /dev/${VN_DEV}s0 &&
 148             echo "Formatted initrd image with UFS" ||
 149             error 1 "Failed to format the initrd image"
 150         mount_ufs /dev/${VN_DEV}s0 ${BUILD_DIR} &&
 151             echo "Mounted initrd image on ${BUILD_DIR}" ||
 152             error 1 "Failed to mount initrd image on ${BUILD_DIR}"
 153 }
 154
 155 destroy_vn() {
 156         umount /dev/${VN_DEV}s0 &&
 157             echo "Unmounted initrd image" ||
 158             error 1 "Failed to umount initrd image"
 159         vnconfig -u ${VN_DEV} &&
 160             echo "Unconfigured ${VN_DEV}" ||
 161             error 1 "Failed to unconfigure ${VN_DEV}"
 162 }
 163
 164 make_hier() {
 165         mkdir -p ${BUILD_DIR}/new_root ||
 166             error 1 "Failed to mkdir ${BUILD_DIR}/new_root"
 167         # Symlink 'sbin' to 'bin'
 168         ln -sf bin ${BUILD_DIR}/sbin
 169         # Symlink 'tmp' to 'var/tmp', as '/var' will be mounted with
 170         # tmpfs, saving a second tmpfs been mounted on '/tmp'.
 171         ln -sf var/tmp ${BUILD_DIR}/tmp
 172         for _dir in ${INITRD_DIRS}; do
 173                 [ ! -d "${BUILD_DIR}/${_dir}" ] &&
 174                     mkdir -p ${BUILD_DIR}/${_dir}
 175         done
 176         echo "Created directory structure"
 177 }
 178
 179 copy_rescue() {
 180         cpdup -o -u ${RESCUE_DIR}/ ${BUILD_DIR}/bin/ &&
 181             echo "Copied ${RESCUE_DIR} to ${BUILD_DIR}/bin" ||
 182             error 1 "Failed to copy ${RESCUE_DIR} to ${BUILD_DIR}/bin"
 183 }
 184
 185 copy_content() {
 186         for _dir in ${CONTENT_DIRS}; do
 187                 cpdup -o -u ${_dir}/ ${BUILD_DIR}/ &&
 188                     echo "Copied ${_dir} to ${BUILD_DIR}" ||
 189                     error 1 "Failed to copy ${dir} to ${BUILD_DIR}"
 190         done
 191 }
 192
 193 print_info() {
 194         lt ${BUILD_DIR}
 195         df -h ${BUILD_DIR}
 196 }
 197
 198 # Check the validity of the created initrd image before moving over.
 199 # This prevents creating an empty and broken initrd image by running
 200 # this tool but without ${CONTENT_DIRS} prepared.
 201 #
 202 # NOTE: Need more improvements.
 203 #
 204 check_initrd()
 205 {
 206         [ -x "${BUILD_DIR}/sbin/oinit" ] &&
 207         [ -x "${BUILD_DIR}/bin/sh" ] &&
 208         [ -x "${BUILD_DIR}/etc/rc" ] || {
 209                 destroy_vn
 210                 error 1 "Ivalid initrd image!"
 211         }
 212 }
 213
 214 usage() {
 215         error 2 \
 216             "usage: ${0##*/} [-b boot_dir] [-r rescue_dir]" \
 217             "[-s size] [-S max_size] -c <content_dirs>"
 218 }
 219
 220
 221 #
 222 # Main
 223 #
 224
 225 while getopts :b:c:hr:s:S: opt; do
 226         case ${opt} in
 227         b)
 228                 BOOT_DIR="${OPTARG}"
 229                 ;;
 230         c)
 231                 CONTENT_DIRS="${OPTARG}"
 232                 ;;
 233         h)
 234                 usage
 235                 ;;
 236         r)
 237                 RESCUE_DIR="${OPTARG}"
 238                 ;;
 239         s)
 240                 INITRD_SIZE="${OPTARG}"
 241                 ;;
 242         S)
 243                 INITRD_SIZE_MAX="${OPTARG}"
 244                 ;;
 245         \?)
 246                 log "Invalid option -${OPTARG}"
 247                 usage
 248                 ;;
 249         :)
 250                 log "Option -${OPTARG} requires an argument"
 251                 usage
 252                 ;;
 253         esac
 254 done
 255
 256 shift $((OPTIND - 1))
 257 [ $# -ne 0 ] && usage
 258 [ -z "${BOOT_DIR}" -o -z "${RESCUE_DIR}" -o -z "${CONTENT_DIRS}" ] && usage
 259 check_dirs ${BOOT_DIR} ${RESCUE_DIR} ${CONTENT_DIRS}
 260
 261 VN_DEV=""
 262 INITRD_SIZE=${INITRD_SIZE%[mM]}  # MB
 263 INITRD_SIZE_MAX=${INITRD_SIZE_MAX%[mM]}  # MB
 264
 265 BUILD_DIR=$(mktemp -d -t initrd) || error $? "Cannot create build directory"
 266 echo "Initrd build directory: ${BUILD_DIR}"
 267 INITRD_FILE="${BUILD_DIR}.img"
 268 INITRD_DEST="${BOOT_DIR}/kernel/initrd.img.gz"
 269
 270 CSIZE=$(calc_initrd_size ${RESCUE_DIR} ${CONTENT_DIRS})
 271 echo "Required initrd image size: ${CSIZE} MB"
 272 if [ -n "${INITRD_SIZE}" -a "${INITRD_SIZE}" != "0" ]; then
 273         if [ ${CSIZE} -gt ${INITRD_SIZE} ]; then
 274                 error 1 "Given initrd size (${INITRD_SIZE} MB) too small"
 275         fi
 276 else
 277         INITRD_SIZE=${CSIZE}
 278 fi
 279 echo "Initrd size: ${INITRD_SIZE} MB"
 280
 281 if [ -n "${INITRD_SIZE_MAX}" -a "${INITRD_SIZE_MAX}" != "0" ] && \
 282    [ ${INITRD_SIZE} -gt ${INITRD_SIZE_MAX} ]; then
 283         error 1 "Exceeded the maximum size (${INITRD_SIZE_MAX} MB)"
 284 fi
 285
 286 create_vn
 287 make_hier
 288 copy_rescue
 289 copy_content
 290 print_info
 291 destroy_vn
 292 rm -rf ${BUILD_DIR}
 293
 294 echo -n "Compressing ${INITRD_FILE} ..."
 295 gzip -9 ${INITRD_FILE}
 296 echo " OK"
 297
 298 if [ -f "${INITRD_DEST}" ]; then
 299         echo -n "Backing up ${INITRD_DEST} ..."
 300         mv ${INITRD_DEST} ${INITRD_DEST}.old
 301         echo " OK (${INITRD_DEST}.old)"
 302 fi
 303
 304 echo -n "Installing ${INITRD_FILE}.gz to ${INITRD_DEST} ..."
 305 install -o root -g wheel -m 444 ${INITRD_FILE}.gz ${INITRD_DEST}
 306 echo " OK"
 307 rm -f ${INITRD_FILE}.gz