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| 1 | +#!/bin/sh |
| 2 | +set -u |
| 3 | +busybox mount -n -t proc proc /proc |
| 4 | +busybox mount -n -t devtmpfs devtmpfs /dev |
| 5 | +busybox mount -n -t sysfs sysfs /sys |
| 6 | +busybox --install -s |
| 7 | +if [ ! -x "/dev/pts" ]; then mkdir /dev/pts; fi |
| 8 | +if [ ! -x "/dev/shm" ]; then mkdir /dev/shm; fi |
| 9 | +busybox mount -n -t devpts devpts /dev/pts -o gid=5,mode=620,ptmxmode=000 |
| 10 | + |
| 11 | +cmdline_arg() { |
| 12 | + local name="$1" |
| 13 | + local value="${2-}" |
| 14 | + for arg in $(cat /proc/cmdline); do |
| 15 | + if [[ "${arg%%=*}" == "${name}" ]]; then |
| 16 | + value="${arg#*=}" |
| 17 | + fi |
| 18 | + done |
| 19 | + echo "${value}" |
| 20 | +} |
| 21 | + |
| 22 | +emergency() { |
| 23 | + echo "ERROR: The early initrd has failed. To activate debug shell breakpoints, boot with rd.earlyshell in the kernel cmdline, and to activate tracing, boot with rd.earlytrace" >&2 |
| 24 | + if read -s -p "Press Enter for emergency shell or wait 60 seconds for reboot." -t 60; then |
| 25 | + echo >&2; echo "Entering emergency mode. Exit the shell to retry /init (you might need to clean up mounts first) or reboot with 'reboot -f'." >&2 |
| 26 | + busybox sh || true |
| 27 | + exec /init |
| 28 | + else |
| 29 | + echo >&2; echo "INFO: Rebooting" >&2 |
| 30 | + exec reboot -f |
| 31 | + fi |
| 32 | +} |
| 33 | +trap 'emergency' ERR |
| 34 | + |
| 35 | +# Custom debug breakpoint |
| 36 | +debug_sh() { |
| 37 | + if [ "$(cmdline_arg rd.earlyshell)" != "" ]; then |
| 38 | + echo "INFO: Entering debug shell breakpoint ($*), exit to continue booting (reboot with 'reboot -f')">&2 |
| 39 | + busybox sh || true |
| 40 | + fi |
| 41 | +} |
| 42 | +debug_sh 1/4: before mdev |
| 43 | +if [ "$(cmdline_arg rd.earlytrace)" != "" ]; then |
| 44 | + set -x |
| 45 | +fi |
| 46 | + |
| 47 | +mdev -d |
| 48 | +mdev -s |
| 49 | +# Coldplugging but with using /sbin/modprobe (which is kmod) instead of busybox's modprobe |
| 50 | +# because busybox doesn't properly support the globs in modules.alias |
| 51 | +find /sys/ -name modalias -print0 | xargs -0 sort -u | tr '\n' '\0' | xargs -0 /sbin/modprobe -abq || true |
| 52 | +# Required to access disks, but not autoloaded: |
| 53 | +modprobe sd_mod |
| 54 | + |
| 55 | +debug_sh 2/4: before verity |
| 56 | + |
| 57 | +find_drive() { |
| 58 | + local search="$1" |
| 59 | + local ueventline= |
| 60 | + local blkidmatch= |
| 61 | + local drive= |
| 62 | + local waitingmsg= |
| 63 | + local starttime= |
| 64 | + local timeoutsecs= |
| 65 | + local now= |
| 66 | + case "${search}" in |
| 67 | + LABEL=*) |
| 68 | + blkidmatch="${search#LABEL=}" |
| 69 | + # Needs " around the value |
| 70 | + blkidmatch="LABEL=\"${blkidmatch}\"" |
| 71 | + ;; |
| 72 | + UUID=*) |
| 73 | + blkidmatch="${search#UUID=}" |
| 74 | + # Needs " around the value |
| 75 | + blkidmatch="UUID=\"$(echo "${blkidmatch}" | tr "[:upper:]" "[:lower:]")\"" |
| 76 | + ;; |
| 77 | + PARTUUID=*) |
| 78 | + ueventline="${search#PARTUUID=}" |
| 79 | + ueventline="PARTUUID=$(echo "${ueventline}" | tr "[:upper:]" "[:lower:]")" |
| 80 | + ;; |
| 81 | + PARTLABEL=*) |
| 82 | + ueventline="PARTNAME=${search#PARTLABEL=}" |
| 83 | + ;; |
| 84 | + *) |
| 85 | + echo "${search}" |
| 86 | + return |
| 87 | + ;; |
| 88 | + esac |
| 89 | + starttime=$(date +%s) |
| 90 | + # Default to 5 minutes |
| 91 | + timeoutsecs=$(cmdline_arg rd.earlytimeout 300) |
| 92 | + while [ "${drive}" = "" ]; do |
| 93 | + now=$(date +%s) |
| 94 | + # Timeout of 5 minutes for finding the device |
| 95 | + # NOTE: Only mdev -d runs as this point and the kernel also can spawn modprobe to load modules. |
| 96 | + # If problems arise, first make sure that required modules and their deps are actually in the initrd, |
| 97 | + # but if that's not enough we might even have to trigger the find /sys ... xargs coldplugging |
| 98 | + # here again every now and then? (Last resort would be to run proper udev, possibly without systemd.) |
| 99 | + if [ $((now - starttime)) -gt "${timeoutsecs}" ]; then |
| 100 | + echo "ERROR: Timeout waiting for drive: ${ueventline}${blkidmatch}" >&2 |
| 101 | + return 1 # Throw error |
| 102 | + fi |
| 103 | + # No "sleep 0.1", so this is rather busy polling |
| 104 | + if [ "${ueventline}" != "" ]; then |
| 105 | + drive="$({ grep -s -l -m 1 -r "${ueventline}" /sys/class/block/*/uevent || true; } | cut -d / -f 5)" |
| 106 | + else |
| 107 | + drive="$(blkid | { grep -m 1 "${blkidmatch}" || true ; } | cut -d : -f 1 | cut -d / -f 3-)" |
| 108 | + fi |
| 109 | + if [ "${drive}" = "" ] && [ "${waitingmsg}" = "" ]; then |
| 110 | + echo "Waiting for drive..." >&2 |
| 111 | + waitingmsg=1 |
| 112 | + fi |
| 113 | + done |
| 114 | + drive="/dev/${drive}" |
| 115 | + echo "${drive}" |
| 116 | +} |
| 117 | + |
| 118 | +# Ported code from the generators |
| 119 | +verityusr=$(cmdline_arg verity.usr) |
| 120 | +usrhash=$(cmdline_arg verity.usrhash) |
| 121 | + |
| 122 | +verityusr=$(find_drive "${verityusr}") |
| 123 | + |
| 124 | +# Only proceed if the source is a path and we have sufficient parameters. |
| 125 | +if echo "${verityusr}" | grep -q "^/" && [ "${usrhash}" != "" ]; then |
| 126 | + # Hardcoded expected value from the image GPT layout |
| 127 | + veritysetup --panic-on-corruption --hash-offset=1065345024 open "${verityusr}" usr "${verityusr}" "${usrhash}" |
| 128 | + # If there's a hash mismatch during table initialization, |
| 129 | + # veritysetup reports it on stderr but still exits 0. |
| 130 | + # Manually check the target status and fail if invalid. |
| 131 | + status=$(dmsetup status usr | cut -d " " -f 4) |
| 132 | + if [ "${status}" != V ]; then |
| 133 | + echo "Verity setup failed" >&2 |
| 134 | + false # Throw error |
| 135 | + fi |
| 136 | +fi |
| 137 | + |
| 138 | +usr=$(cmdline_arg mount.usr $(cmdline_arg usr)) |
| 139 | +usrfstype=$(cmdline_arg mount.usrfstype $(cmdline_arg usrfstype auto)) |
| 140 | +usrflags=$(cmdline_arg mount.usrflags $(cmdline_arg usrflags ro)) |
| 141 | + |
| 142 | +usr=$(find_drive "${usr}") |
| 143 | + |
| 144 | +if [ "${usr}" = "" ] && [ -f /usr.squashfs ]; then |
| 145 | + usr=/usr.squashfs |
| 146 | + usrfstype=squashfs |
| 147 | +elif [ "${usrfstype}" = btrfs ] || [ "${usrfstype}" = auto ]; then |
| 148 | + if [ "$(echo ",${usrflags}," | grep -v -F ',ro,')" != "" ]; then |
| 149 | + true # Don't set "norecovery" when mounting rw |
| 150 | + else |
| 151 | + usrflags="${usrflags},rescue=nologreplay" |
| 152 | + fi |
| 153 | +fi |
| 154 | +# Only proceed if the source is a path. |
| 155 | +case "${usr}" in |
| 156 | + /*) : ;; |
| 157 | + *) echo "No mountable /usr partition given (usr='${usr}')" >&2 |
| 158 | + false # Throw error |
| 159 | + ;; |
| 160 | +esac |
| 161 | + |
| 162 | +debug_sh 3/4: before /sysusr mount |
| 163 | + |
| 164 | +echo "Mounting /usr from ${usr}" >&2 |
| 165 | +# mount -t auto only works if btrfs is already loaded |
| 166 | +modprobe btrfs |
| 167 | +mkdir -p /sysusr/usr |
| 168 | +mount -t "${usrfstype}" -o "${usrflags}" "${usr}" /sysusr/usr |
| 169 | + |
| 170 | +# Busybox doesn't load this for us |
| 171 | +modprobe loop |
| 172 | +LOOP=$(losetup -f) |
| 173 | +losetup -r "${LOOP}" /sysusr/usr/lib/flatcar/bootengine.img |
| 174 | +mkdir /underlay /work |
| 175 | +mount -t tmpfs tmpfs /work |
| 176 | +mkdir /work/realinit /work/work |
| 177 | +mount -t squashfs "${LOOP}" /underlay |
| 178 | +mkdir -p /realinit |
| 179 | +mount -t overlay -o rw,lowerdir=/underlay,upperdir=/work/realinit,workdir=/work/work overlay /realinit |
| 180 | +mkdir -p /realinit/sysusr/usr |
| 181 | +mount -o move /sysusr/usr /realinit/sysusr/usr |
| 182 | +if [ "${usr}" = /usr.squashfs ]; then |
| 183 | + mkdir -p /oem |
| 184 | + mkdir -p /realinit/oem |
| 185 | + mount -o bind /oem /realinit/oem |
| 186 | + touch /realinit/usr.squashfs |
| 187 | + mount -o bind /usr.squashfs /realinit/usr.squashfs |
| 188 | +fi |
| 189 | +debug_sh 4/4: before switch_root to /realinit |
| 190 | +killall mdev || true |
| 191 | +umount /proc |
| 192 | +umount /sys |
| 193 | +umount /dev/pts |
| 194 | +# Lazy unmount because /dev/console is held by the current process |
| 195 | +umount -l /dev |
| 196 | +exec switch_root /realinit /init |
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