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 initrad
  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
  69 #
  70 # Helper functions
  71 #
  72
  73 log() {
  74         echo "$@" >&2
  75 }
  76
  77 error() {
  78         local rc=$1
  79         shift
  80         log "$@"
  81         exit ${rc}
  82 }
  83
  84 check_dirs() {
  85         for _dir; do
  86                 [ -d "${_dir}" ] ||
  87                     error 1 "Directory '${_dir}' does not exist"
  88         done
  89         return 0
  90 }
  91
  92 # Calculate the total size of the given directory, taking care of the
  93 # hard links.
  94 #
  95 # NOTE: Do not use 'du' since it gives the disk usage of the files,
  96 #       which varies between different filesystems.
  97 #
  98 calc_size() {
  99         find "$1" -ls | \
 100             awk '{ print $7,$1 }' | \
 101             sort -n -k 2 | \
 102             uniq -f 1 | \
 103             awk '{ sum+=$1 } END { print sum }'  # byte
 104 }
 105
 106
 107 #
 108 # Functions
 109 #
 110
 111 calc_initrd_size() {
 112         log "Calculating required initrd size ..."
 113         isize=0
 114         for _dir; do
 115                 csize=$(calc_size ${_dir})
 116                 log "* ${_dir}: ${csize} bytes"
 117                 isize=$((${isize} + ${csize}))
 118         done
 119         # Round initrd size up by MB
 120         isize_mb=$(echo ${isize} | awk '
 121             function ceil(x) {
 122                 y = int(x);
 123                 return (x>y ? y+1 : y);
 124             }
 125             {
 126                 mb = $1/1024/1024;
 127                 print ceil(mb);
 128             }')
 129         # Add additional 1 MB
 130         echo $((${isize_mb} + 1))
 131 }
 132
 133 create_vn() {
 134         kldload -n vn
 135         VN_DEV=$(vnconfig -c -S ${INITRD_SIZE}m -Z -T vn ${INITRD_FILE}) &&
 136             echo "Configured ${VN_DEV}" ||
 137             error 1 "Failed to configure VN device"
 138
 139         newfs -i 131072 -m 0 /dev/${VN_DEV}s0 &&
 140             echo "Formatted initrd image with UFS" ||
 141             error 1 "Failed to format the initrd image"
 142         mount_ufs /dev/${VN_DEV}s0 ${BUILD_DIR} &&
 143             echo "Mounted initrd image on ${BUILD_DIR}" ||
 144             error 1 "Failed to mount initrd image on ${BUILD_DIR}"
 145 }
 146
 147 destroy_vn() {
 148         umount /dev/${VN_DEV}s0 &&
 149             echo "Unmounted initrd image" ||
 150             error 1 "Failed to umount initrd image"
 151         vnconfig -u ${VN_DEV} &&
 152             echo "Unconfigured ${VN_DEV}" ||
 153             error 1 "Failed to unconfigure ${VN_DEV}"
 154 }
 155
 156 make_hier() {
 157         mkdir -p ${BUILD_DIR}/new_root ||
 158             error 1 "Failed to mkdir ${BUILD_DIR}/new_root"
 159         # Symlink 'sbin' to 'bin'
 160         ln -sf bin ${BUILD_DIR}/sbin
 161         # Symlink 'tmp' to 'var/tmp', as '/var' will be mounted with
 162         # tmpfs, saving a second tmpfs been mounted on '/tmp'.
 163         ln -sf var/tmp ${BUILD_DIR}/tmp
 164         for _dir in ${INITRD_DIRS}; do
 165                 [ ! -d "${BUILD_DIR}/${_dir}" ] &&
 166                     mkdir -p ${BUILD_DIR}/${_dir}
 167         done
 168         echo "Created directory structure"
 169 }
 170
 171 copy_rescue() {
 172         cpdup -o -u ${RESCUE_DIR}/ ${BUILD_DIR}/bin/ &&
 173             echo "Copied ${RESCUE_DIR} to ${BUILD_DIR}/bin" ||
 174             error 1 "Failed to copy ${RESCUE_DIR} to ${BUILD_DIR}/bin"
 175 }
 176
 177 copy_content() {
 178         for _dir in ${CONTENT_DIRS}; do
 179                 cpdup -o -u ${_dir}/ ${BUILD_DIR}/ &&
 180                     echo "Copied ${_dir} to ${BUILD_DIR}" ||
 181                     error 1 "Failed to copy ${dir} to ${BUILD_DIR}"
 182         done
 183 }
 184
 185 print_info() {
 186         lt ${BUILD_DIR}
 187         df -h ${BUILD_DIR}
 188 }
 189
 190 # Check the validity of the created initrd image before moving over.
 191 # This prevents creating an empty and broken initrd image by running
 192 # this tool but without ${CONTENT_DIRS} prepared.
 193 #
 194 # NOTE: Need more improvements.
 195 #
 196 check_initrd()
 197 {
 198         [ -x "${BUILD_DIR}/sbin/oinit" ] &&
 199         [ -x "${BUILD_DIR}/bin/sh" ] &&
 200         [ -x "${BUILD_DIR}/etc/rc" ] || {
 201                 destroy_vn
 202                 error 1 "Ivalid initrd image!"
 203         }
 204 }
 205
 206 usage() {
 207         error 2 \
 208             "usage: ${0##*/} [-b boot_dir] [-r rescue_dir]" \
 209             "[-s size] [-S max_size] -c <content_dirs>"
 210 }
 211
 212
 213 #
 214 # Main
 215 #
 216
 217 while getopts :b:c:hr:s:S: opt; do
 218         case ${opt} in
 219         b)
 220                 BOOT_DIR="${OPTARG}"
 221                 ;;
 222         c)
 223                 CONTENT_DIRS="${OPTARG}"
 224                 ;;
 225         h)
 226                 usage
 227                 ;;
 228         r)
 229                 RESCUE_DIR="${OPTARG}"
 230                 ;;
 231         s)
 232                 INITRD_SIZE="${OPTARG}"
 233                 ;;
 234         S)
 235                 INITRD_SIZE_MAX="${OPTARG}"
 236                 ;;
 237         \?)
 238                 log "Invalid option -${OPTARG}"
 239                 usage
 240                 ;;
 241         :)
 242                 log "Option -${OPTARG} requires an argument"
 243                 usage
 244                 ;;
 245         esac
 246 done
 247
 248 shift $((OPTIND - 1))
 249 [ $# -ne 0 ] && usage
 250 [ -z "${BOOT_DIR}" -o -z "${RESCUE_DIR}" -o -z "${CONTENT_DIRS}" ] && usage
 251 check_dirs ${BOOT_DIR} ${RESCUE_DIR} ${CONTENT_DIRS}
 252
 253 VN_DEV=""
 254 INITRD_SIZE=${INITRD_SIZE%[mM]}  # MB
 255 INITRD_SIZE_MAX=${INITRD_SIZE_MAX%[mM]}  # MB
 256
 257 BUILD_DIR=$(mktemp -d -t initrd) || error $? "Cannot create build directory"
 258 echo "Initrd build directory: ${BUILD_DIR}"
 259 INITRD_FILE="${BUILD_DIR}.img"
 260 INITRD_DEST="${BOOT_DIR}/kernel/initrd.img.gz"
 261
 262 CSIZE=$(calc_initrd_size ${RESCUE_DIR} ${CONTENT_DIRS})
 263 echo "Required initrd image size: ${CSIZE} MB"
 264 if [ -n "${INITRD_SIZE}" -a "${INITRD_SIZE}" != "0" ]; then
 265         if [ ${CSIZE} -gt ${INITRD_SIZE} ]; then
 266                 error 1 "Given initrd size (${INITRD_SIZE} MB) too small"
 267         fi
 268 else
 269         INITRD_SIZE=${CSIZE}
 270 fi
 271 echo "Initrd size: ${INITRD_SIZE} MB"
 272
 273 if [ -n "${INITRD_SIZE_MAX}" -a "${INITRD_SIZE_MAX}" != "0" ] && \
 274    [ ${INITRD_SIZE} -gt ${INITRD_SIZE_MAX} ]; then
 275         error 1 "Exceeded the maximum size (${INITRD_SIZE_MAX} MB)"
 276 fi
 277
 278 create_vn
 279 make_hier
 280 copy_rescue
 281 copy_content
 282 print_info
 283 destroy_vn
 284 rm -rf ${BUILD_DIR}
 285
 286 echo -n "Compressing ${INITRD_FILE} ..."
 287 gzip -9 ${INITRD_FILE}
 288 echo " OK"
 289
 290 if [ -f "${INITRD_DEST}" ]; then
 291         echo -n "Backing up ${INITRD_DEST} ..."
 292         mv ${INITRD_DEST} ${INITRD_DEST}.old
 293         echo " OK (${INITRD_DEST}.old)"
 294 fi
 295
 296 echo -n "Copying ${INITRD_FILE}.gz to ${INITRD_DEST} ..."
 297 install -o root -g wheel -m 444 ${INITRD_FILE}.gz ${INITRD_DEST}
 298 echo " OK"
 299 rm -f ${INITRD_FILE}.gz