patch shim initramfs

bootloader/bootstrap.sh

@@ -0,0 +1,44 @@
+#!/bin/busybox sh
+# Copyright 2015 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+#
+# To bootstrap the factory installer on rootfs. This file must be executed as
+# PID=1 (exec).
+# Note that this script uses the busybox shell (not bash, not dash).
+
+#original: https://chromium.googlesource.com/chromiumos/platform/initramfs/+/refs/heads/main/factory_shim/bootstrap.sh
+
+set +x
+
+invoke_terminal() {
+  local tty="$1"
+  local title="$2"
+  shift
+  shift
+  # Copied from factory_installer/factory_shim_service.sh.
+  echo "${title}" >>${tty}
+  setsid sh -c "exec script -afqc '$*' /dev/null <${tty} >>${tty} 2>&1 &"
+}
+
+enable_debug_console() {
+  local tty="$1"
+  info -e '\033[1;33m[cros_debug] enabled on '${tty}'.\033[m'
+  invoke_terminal "${tty}" "[Bootstrap Debug Console]" "/bin/busybox sh"
+}
+
+
+main() {
+  # Setup environment.
+  #kill_frecon
+  #tty_init
+
+  info "...:::||| Bootstrapping ChromeOS Factory Shim |||:::..."
+  info "TTY: ${TTY}, LOG: ${LOG_TTY}, INFO: ${INFO_TTY}, DEBUG: ${DEBUG_TTY}"
+  echo "idk please work"
+
+  enable_debug_console "/dev/pts/0"
+}
+
+main "$@"
+sleep 1d

bootloader/init.sh

@@ -0,0 +1,30 @@
+#!/bin/busybox sh
+# Copyright 2015 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+#
+# /init script for use in factory install shim.
+# Note that this script uses the busybox shell (not bash, not dash).
+
+#original: https://chromium.googlesource.com/chromiumos/platform/initramfs/+/refs/heads/main/factory_shim/init
+
+set -x
+
+. /lib/init.sh
+
+setup_environment() {
+  initialize
+
+  # Install additional utility programs.
+  /bin/busybox --install /bin || true
+}
+
+main() {
+  setup_environment
+  # In case an error is not handled by bootstrapping, stop here
+  # so that an operator can see installation stop.
+  exec bootstrap.sh || sleep 1d
+}
+
+main "$@"
+exit 1

build.sh

@@ -56,10 +56,13 @@ echo "extracting initramfs cpio archive"
 initramfs_dir=/tmp/shim_initramfs
 rm -rf $initramfs_dir
 cat $cpio_file | cpio -D $initramfs_dir -imd --quiet
-
 echo "shim initramfs extracted to ${initramfs_dir}"
 
+#leave /tmp
 cd $previous_dir
 
+echo "patching initramfs"
+exec ./patch_initramfs.sh $initramfs_dir
+
 echo "cleaning up loop devices"
 losetup -d $shim_loop

patch_initramfs.sh

@@ -0,0 +1,15 @@
+#!/bin/bash
+
+#patch the shim initramfs to add the bootloader
+
+set -e
+if [ "$DEBUG" ]; then
+  set -x
+fi
+
+initramfs_path=$(realpath $1)
+
+rm "${initramfs_path}/init" -f
+cp bootloader/init.sh "${initramfs_path}/sbin/init"
+cp bootloader/bootstrap.sh "${initramfs_path}/sbin/bootstrap.sh"
+chmod +x "${initramfs_path}/sbin/*.sh"