From 86269dfa0559a3c14af009ffe4fcf81cb0b2025c Mon Sep 17 00:00:00 2001
From: ading2210 <ading2019@gmail.com>
Date: Wed, 20 Dec 2023 22:05:17 -0800
Subject: [PATCH 1/7] move initramfs extraction to separate script

---
 .gitignore        |  2 +-
 build.sh          | 28 ++--------------------------
 build_squashfs.sh | 10 ++++++++++
 shim_utils.sh     | 25 +++++++++++++++++++++++++
 4 files changed, 38 insertions(+), 27 deletions(-)
 create mode 100755 build_squashfs.sh
 create mode 100755 shim_utils.sh

diff --git a/.gitignore b/.gitignore
index f5e92d4..61fa5b9 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,2 @@
 /data
-/test.bin
\ No newline at end of file
+/*.bin
\ No newline at end of file
diff --git a/build.sh b/build.sh
index d62440c..920e1ae 100755
--- a/build.sh
+++ b/build.sh
@@ -9,6 +9,7 @@ fi
 
 . ./patch_initramfs.sh
 . ./build_image.sh
+. ./shim_utils.sh
 
 print_help() {
   echo "Usage: ./build.sh output_path shim_path rootfs_dir"
@@ -55,34 +56,9 @@ mkdir $kernel_dir -p
 dd if=$kernel_loop of=$kernel_dir/kernel.bin bs=1M status=none
 
 echo "extracting data from kernel"
-previous_dir=$(pwd)
-cd $kernel_dir
-if [ -e "${kernel_dir}/binwalk.out" ]; then
-  #don't run binwalk again if we don't need to
-  binwalk_out=$(cat $kernel_dir/binwalk.out)
-else
-  binwalk_out=$(binwalk --extract kernel.bin --run-as=root)
-  echo $binwalk_out > $kernel_dir/binwalk.out
-fi
-#i can't be bothered to learn how to use sed
-extracted_file=$(echo $binwalk_out | pcregrep -o1 "\d+\s+0x([0-9A-F]+)\s+gzip compressed data")
-
-echo "extracting initramfs archive from kernel (this may take a while)"
-cd _kernel.bin.extracted/
-if [ ! -e "_${extracted_file}.extracted/" ]; then
-  binwalk --extract $extracted_file --run-as=root > /dev/null
-fi
-cd "_${extracted_file}.extracted/"
-cpio_file=$(file ./* | pcregrep -o1 "([0-9A-F]+):\s+ASCII cpio archive")
-
-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
+extract_initramfs $kernel_dir/kernel.bin $kernel_dir $initramfs_dir
 
 echo "patching initramfs"
 patch_initramfs $initramfs_dir
diff --git a/build_squashfs.sh b/build_squashfs.sh
new file mode 100755
index 0000000..6e1f508
--- /dev/null
+++ b/build_squashfs.sh
@@ -0,0 +1,10 @@
+#!/bin/bash
+
+#build a rootfs that uses a squashfs + unionfs
+#consists of a minimal busybox system containing:
+# - FUSE kernel modules from the shim
+# - unionfs-fuse statically compiled 
+# - the main squashfs, compressed with gzip
+
+
+#todo - gotta refactor the other build scripts first
\ No newline at end of file
diff --git a/shim_utils.sh b/shim_utils.sh
new file mode 100755
index 0000000..e2e5582
--- /dev/null
+++ b/shim_utils.sh
@@ -0,0 +1,25 @@
+#!/bin/bash
+
+#utilties for reading shim disk images
+
+extract_initramfs() {
+  local kernel_bin="$1"
+  local working_dir="$2"
+  local output_dir="$3"
+
+  #first stage
+  local kernel_file="$(basename $kernel_bin)"
+  local binwalk_out=$(binwalk --extract $kernel_bin --directory=$working_dir --run-as=root)
+  local stage1_file=$(echo $binwalk_out | pcregrep -o1 "\d+\s+0x([0-9A-F]+)\s+gzip compressed data")
+  local stage1_dir="$working_dir/_$kernel_file.extracted"
+  local stage1_path="$stage1_dir/$stage1_file"
+  
+  #second stage
+  binwalk --extract $stage1_path --directory=$stage1_dir --run-as=root
+  local stage2_dir="$stage1_dir/_$stage1_file.extracted/"
+  local cpio_file=$(file $stage2_dir/* | pcregrep -o1 "([0-9A-F]+):\s+ASCII cpio archive")
+  local cpio_path="$stage2_dir/$cpio_file"
+
+  rm -rf $output_dir
+  cat $cpio_path | cpio -D $output_dir -imd --quiet
+}
\ No newline at end of file

From 2995760db483205ffb74561cef2b2b182dc2a819 Mon Sep 17 00:00:00 2001
From: ading2210 <ading2019@gmail.com>
Date: Wed, 20 Dec 2023 22:09:41 -0800
Subject: [PATCH 2/7] better naming for build utils

---
 build.sh                         |  3 +--
 build_image.sh => image_utils.sh | 14 +++++++++-----
 patch_initramfs.sh               | 17 -----------------
 3 files changed, 10 insertions(+), 24 deletions(-)
 rename build_image.sh => image_utils.sh (94%)
 delete mode 100755 patch_initramfs.sh

diff --git a/build.sh b/build.sh
index 920e1ae..22aad82 100755
--- a/build.sh
+++ b/build.sh
@@ -7,8 +7,7 @@ if [ "$DEBUG" ]; then
   set -x
 fi
 
-. ./patch_initramfs.sh
-. ./build_image.sh
+. ./image_utils.sh
 . ./shim_utils.sh
 
 print_help() {
diff --git a/build_image.sh b/image_utils.sh
similarity index 94%
rename from build_image.sh
rename to image_utils.sh
index 5dcf7ef..76b0122 100755
--- a/build_image.sh
+++ b/image_utils.sh
@@ -1,10 +1,5 @@
 #!/bin/bash
 
-set -e
-if [ "$DEBUG" ]; then
-  set -x
-fi
-
 create_loop() {
   local loop_device=$(losetup -f)
   losetup -P $loop_device "${1}"
@@ -128,4 +123,13 @@ create_image() {
   fallocate -l "${total_size}M" "${image_path}"
 
   partition_disk $image_path $bootloader_size
+}
+
+patch_initramfs() {
+  local initramfs_path=$(realpath $1)
+
+  rm "${initramfs_path}/init" -f
+  cp -r bootloader/* "${initramfs_path}/"
+
+  find ${initramfs_path}/bin -name "*" -exec chmod +x {} \;
 }
\ No newline at end of file
diff --git a/patch_initramfs.sh b/patch_initramfs.sh
deleted file mode 100755
index 7d0cf01..0000000
--- a/patch_initramfs.sh
+++ /dev/null
@@ -1,17 +0,0 @@
-#!/bin/bash
-
-#patch the shim initramfs to add the bootloader
-
-set -e
-if [ "$DEBUG" ]; then
-  set -x
-fi
-
-patch_initramfs() {
-  local initramfs_path=$(realpath $1)
-
-  rm "${initramfs_path}/init" -f
-  cp -r bootloader/* "${initramfs_path}/"
-
-  find ${initramfs_path}/bin -name "*" -exec chmod +x {} \;
-}

From e399ef002e9372cc7f2946b59d4f30e0ee8e9ef2 Mon Sep 17 00:00:00 2001
From: ading2210 <ading2019@gmail.com>
Date: Wed, 20 Dec 2023 22:48:32 -0800
Subject: [PATCH 3/7] extract modules to squashfs

---
 build_squashfs.sh | 72 ++++++++++++++++++++++++++++++++++++++++++++++-
 shim_utils.sh     |  7 +++++
 2 files changed, 78 insertions(+), 1 deletion(-)

diff --git a/build_squashfs.sh b/build_squashfs.sh
index 6e1f508..c7fc630 100755
--- a/build_squashfs.sh
+++ b/build_squashfs.sh
@@ -5,6 +5,76 @@
 # - FUSE kernel modules from the shim
 # - unionfs-fuse statically compiled 
 # - the main squashfs, compressed with gzip
+#this script is currently incomplete
 
+set -e
+if [ "$DEBUG" ]; then
+  set -x
+fi
 
-#todo - gotta refactor the other build scripts first
\ No newline at end of file
+. ./image_utils.sh
+. ./shim_utils.sh
+
+print_help() {
+  echo "Usage: ./build_squashfs.sh rootfs_dir uncompressed_rootfs_dir path_to_shim"
+}
+
+if [ "$EUID" -ne 0 ]; then
+  echo "this needs to be run as root."
+  exit 1
+fi
+
+if [ -z "$3" ]; then
+  print_help
+  exit 1
+fi
+
+compile_unionfs() {
+  local out_path="$1"
+  local working_path="$2"
+
+  local repo_url="https://github.com/rpodgorny/unionfs-fuse"
+  local original_dir="$(pwd)"
+  
+  rm -rf $working_path
+  git clone $repo_url -b master --depth=1 $working_path
+  cd $working_path
+
+  env LDFLAGS="-static" make
+  local binary_path="$working_path/src/unionfs"
+  cp $binary_path $out_path
+}
+
+rootfs_dir=$(realpath $1)
+target_dir=$(realpath $2)
+shim_path=$(realpath $3)
+
+shim_rootfs="/tmp/shim_rootfs"
+modules_squashfs="/tmp/modules.squashfs"
+kernel_dir=/tmp/shim_kernel
+initramfs_dir=/tmp/shim_initramfs
+
+echo "compiling unionfs-fuse"
+compile_unionfs /tmp/unionfs /tmp/unionfs-fuse 
+
+echo "mounting shim"
+shim_loop=$(create_loop "${shim_path}")
+make_mountable "${shim_loop}p3"
+safe_mount "${shim_loop}p3" $shim_rootfs
+
+echo "extracting modules from shim"
+extract_modules $modules_squashfs $shim_rootfs
+
+echo "copying shim kernel"
+mkdir $kernel_dir -p
+kernel_loop="${shim_loop}p2"
+dd if=$kernel_loop of=$kernel_dir/kernel.bin bs=1M status=none
+
+echo "extracting initramfs from kernel"
+extract_initramfs $kernel_dir/kernel.bin $kernel_dir $rootfs_dir
+
+#todo...
+
+echo "cleaning up"
+umount $shim_rootfs
+losetup -d $shim_loop
\ No newline at end of file
diff --git a/shim_utils.sh b/shim_utils.sh
index e2e5582..704e27b 100755
--- a/shim_utils.sh
+++ b/shim_utils.sh
@@ -22,4 +22,11 @@ extract_initramfs() {
 
   rm -rf $output_dir
   cat $cpio_path | cpio -D $output_dir -imd --quiet
+}
+
+extract_modules() {
+  local output_path="$1"
+  local shim_rootfs="$2"
+  local modules_dir="$shim_rootfs/lib/modules"
+  mksquashfs $modules_dir $output_path -noappend -comp gzip
 }
\ No newline at end of file

From 11621e15b5dc2a9b4496db89e7adc3e8d0c37ca8 Mon Sep 17 00:00:00 2001
From: ading2210 <ading2019@gmail.com>
Date: Thu, 21 Dec 2023 16:58:08 -0800
Subject: [PATCH 4/7] more build script improvements

---
 build_rootfs.sh   |  5 +++--
 build_squashfs.sh | 36 +++++++++++++++++++++++-------------
 shim_utils.sh     |  2 +-
 3 files changed, 27 insertions(+), 16 deletions(-)

diff --git a/build_rootfs.sh b/build_rootfs.sh
index 915bf05..96886a8 100755
--- a/build_rootfs.sh
+++ b/build_rootfs.sh
@@ -8,7 +8,7 @@ if [ "$DEBUG" ]; then
 fi
 
 print_help() {
-  echo "Usage: ./build_rootfs.sh rootfs_path release_name"
+  echo "Usage: ./build_rootfs.sh rootfs_path release_name [custom_packages]"
 }
 
 check_deps() {
@@ -40,6 +40,7 @@ fi
 
 rootfs_dir=$(realpath "${1}")
 release_name="${2}"
+packages="${3-'task-xfce-desktop'}"
 
 debootstrap --arch amd64 $release_name $rootfs_dir http://deb.debian.org/debian/
 cp -ar rootfs/* $rootfs_dir
@@ -49,7 +50,7 @@ for mountpoint in $chroot_mounts; do
   mount --make-rslave --rbind "/${mountpoint}" "${rootfs_dir}/$mountpoint"
 done
 
-chroot_command="DEBUG=${DEBUG} release_name=${release_name} /opt/setup_rootfs.sh"
+chroot_command="DEBUG=${DEBUG} release_name=${release_name} packages=${packages} /opt/setup_rootfs.sh"
 chroot $rootfs_dir /bin/bash -c "${chroot_command}"
 
 for mountpoint in $chroot_mounts; do
diff --git a/build_squashfs.sh b/build_squashfs.sh
index c7fc630..dc0863c 100755
--- a/build_squashfs.sh
+++ b/build_squashfs.sh
@@ -46,34 +46,44 @@ compile_unionfs() {
 }
 
 rootfs_dir=$(realpath $1)
-target_dir=$(realpath $2)
+old_dir=$(realpath $2)
 shim_path=$(realpath $3)
 
 shim_rootfs="/tmp/shim_rootfs"
-modules_squashfs="/tmp/modules.squashfs"
+root_squashfs="$rootfs_dir/root.squashfs"
+modules_squashfs="$rootfs_dir/modules.squashfs"
 kernel_dir=/tmp/shim_kernel
-initramfs_dir=/tmp/shim_initramfs
+unionfs_dir="/tmp/unionfs-fuse"
 
 echo "compiling unionfs-fuse"
-compile_unionfs /tmp/unionfs /tmp/unionfs-fuse 
+compile_unionfs $unionfs_dir/unionfs $unionfs_dir
 
-echo "mounting shim"
+echo "creating loop device for shim"
 shim_loop=$(create_loop "${shim_path}")
-make_mountable "${shim_loop}p3"
-safe_mount "${shim_loop}p3" $shim_rootfs
-
-echo "extracting modules from shim"
-extract_modules $modules_squashfs $shim_rootfs
+kernel_loop="${shim_loop}p2" #KERN-A should always be p2
 
 echo "copying shim kernel"
+rm -rf $kernel_dir
 mkdir $kernel_dir -p
-kernel_loop="${shim_loop}p2"
-dd if=$kernel_loop of=$kernel_dir/kernel.bin bs=1M status=none
+dd if=$kernel_loop of=$kernel_dir/kernel.bin bs=1M status=progress
 
 echo "extracting initramfs from kernel"
 extract_initramfs $kernel_dir/kernel.bin $kernel_dir $rootfs_dir
+rm -rf $rootfs_dir/init
 
-#todo...
+echo "mounting shim"
+make_mountable "${shim_loop}p3"
+safe_mount "${shim_loop}p3" $shim_rootfs
+
+echo "extracting and compressing modules from shim"
+extract_modules $modules_squashfs $shim_rootfs
+
+echo "compressing old rootfs"
+mksquashfs $old_dir $root_squashfs -noappend -comp gzip
+
+echo "patching new rootfs"
+mv $unionfs_dir/unionfs $rootfs_dir/bin/unionfs
+#cp -ar ./squashfs/* $rootfs_dir/
 
 echo "cleaning up"
 umount $shim_rootfs
diff --git a/shim_utils.sh b/shim_utils.sh
index 704e27b..fe83aad 100755
--- a/shim_utils.sh
+++ b/shim_utils.sh
@@ -15,7 +15,7 @@ extract_initramfs() {
   local stage1_path="$stage1_dir/$stage1_file"
   
   #second stage
-  binwalk --extract $stage1_path --directory=$stage1_dir --run-as=root
+  binwalk --extract $stage1_path --directory=$stage1_dir --run-as=root > /dev/null
   local stage2_dir="$stage1_dir/_$stage1_file.extracted/"
   local cpio_file=$(file $stage2_dir/* | pcregrep -o1 "([0-9A-F]+):\s+ASCII cpio archive")
   local cpio_path="$stage2_dir/$cpio_file"

From e8b2f15d7b9aec738ad544e618424e9e99d1799f Mon Sep 17 00:00:00 2001
From: ading2210 <ading2019@gmail.com>
Date: Thu, 21 Dec 2023 22:51:47 -0800
Subject: [PATCH 5/7] working init for squashfs boot

---
 build.sh                   |  1 +
 build_rootfs.sh            |  2 +-
 build_squashfs.sh          | 16 ++++-----
 rootfs/opt/setup_rootfs.sh |  9 +++--
 shim_utils.sh              |  7 ----
 squashfs/bin/bootstrap.sh  | 68 ++++++++++++++++++++++++++++++++++++++
 squashfs/bin/init          | 29 ++++++++++++++++
 7 files changed, 113 insertions(+), 19 deletions(-)
 create mode 100755 squashfs/bin/bootstrap.sh
 create mode 100755 squashfs/bin/init

diff --git a/build.sh b/build.sh
index 22aad82..842ffe4 100755
--- a/build.sh
+++ b/build.sh
@@ -84,6 +84,7 @@ echo "copying data into the image"
 populate_partitions $image_loop $initramfs_dir $rootfs_dir
 
 echo "cleaning up loop devices"
+umount $rootfs_dir
 losetup -d $shim_loop
 losetup -d $image_loop
 echo "done"
\ No newline at end of file
diff --git a/build_rootfs.sh b/build_rootfs.sh
index 96886a8..4669ab7 100755
--- a/build_rootfs.sh
+++ b/build_rootfs.sh
@@ -50,7 +50,7 @@ for mountpoint in $chroot_mounts; do
   mount --make-rslave --rbind "/${mountpoint}" "${rootfs_dir}/$mountpoint"
 done
 
-chroot_command="DEBUG=${DEBUG} release_name=${release_name} packages=${packages} /opt/setup_rootfs.sh"
+chroot_command="/opt/setup_rootfs.sh '$DEBUG' '$release_name' '$packages'"
 chroot $rootfs_dir /bin/bash -c "${chroot_command}"
 
 for mountpoint in $chroot_mounts; do
diff --git a/build_squashfs.sh b/build_squashfs.sh
index dc0863c..edd3d36 100755
--- a/build_squashfs.sh
+++ b/build_squashfs.sh
@@ -35,14 +35,16 @@ compile_unionfs() {
 
   local repo_url="https://github.com/rpodgorny/unionfs-fuse"
   local original_dir="$(pwd)"
+  local core_count="$(nproc --all)"
   
   rm -rf $working_path
   git clone $repo_url -b master --depth=1 $working_path
   cd $working_path
 
-  env LDFLAGS="-static" make
+  env LDFLAGS="-static" make -j$core_count
   local binary_path="$working_path/src/unionfs"
   cp $binary_path $out_path
+  cd $original_dir
 }
 
 rootfs_dir=$(realpath $1)
@@ -67,7 +69,7 @@ rm -rf $kernel_dir
 mkdir $kernel_dir -p
 dd if=$kernel_loop of=$kernel_dir/kernel.bin bs=1M status=progress
 
-echo "extracting initramfs from kernel"
+echo "extracting initramfs from kernel (this may take a while)"
 extract_initramfs $kernel_dir/kernel.bin $kernel_dir $rootfs_dir
 rm -rf $rootfs_dir/init
 
@@ -75,16 +77,12 @@ echo "mounting shim"
 make_mountable "${shim_loop}p3"
 safe_mount "${shim_loop}p3" $shim_rootfs
 
-echo "extracting and compressing modules from shim"
-extract_modules $modules_squashfs $shim_rootfs
-
 echo "compressing old rootfs"
 mksquashfs $old_dir $root_squashfs -noappend -comp gzip
 
 echo "patching new rootfs"
 mv $unionfs_dir/unionfs $rootfs_dir/bin/unionfs
-#cp -ar ./squashfs/* $rootfs_dir/
+cp -ar squashfs/* $rootfs_dir/
+chmod +x $rootfs_dir/bin/*
 
-echo "cleaning up"
-umount $shim_rootfs
-losetup -d $shim_loop
\ No newline at end of file
+echo "done"
\ No newline at end of file
diff --git a/rootfs/opt/setup_rootfs.sh b/rootfs/opt/setup_rootfs.sh
index fee86d0..6fda0a7 100755
--- a/rootfs/opt/setup_rootfs.sh
+++ b/rootfs/opt/setup_rootfs.sh
@@ -3,6 +3,10 @@
 #setup the debian rootfs
 #this is meant to be run within the chroot created by debootstrap
 
+DEBUG="$1"
+release_name="$2"
+packages="$3"
+
 set -e
 if [ "$DEBUG" ]; then
   set -x
@@ -23,13 +27,14 @@ END
 #install the patched systemd
 apt-get install -y ca-certificates
 apt-get update
-apt-get upgrade -y 
+installed_systemd="$(dpkg-query -W -f='${binary:Package}\n' | grep "systemd")"
+apt-get install --reinstall $installed_systemd
 
 #enable shimboot services
 systemctl enable kill-frecon.service
 
 #install desktop
-apt-get install -y task-xfce-desktop cloud-utils zram-tools
+apt-get install -y $packages cloud-utils zram-tools
 
 #set up zram
 tee -a /etc/default/zramswap << END
diff --git a/shim_utils.sh b/shim_utils.sh
index fe83aad..113b2bb 100755
--- a/shim_utils.sh
+++ b/shim_utils.sh
@@ -23,10 +23,3 @@ extract_initramfs() {
   rm -rf $output_dir
   cat $cpio_path | cpio -D $output_dir -imd --quiet
 }
-
-extract_modules() {
-  local output_path="$1"
-  local shim_rootfs="$2"
-  local modules_dir="$shim_rootfs/lib/modules"
-  mksquashfs $modules_dir $output_path -noappend -comp gzip
-}
\ No newline at end of file
diff --git a/squashfs/bin/bootstrap.sh b/squashfs/bin/bootstrap.sh
new file mode 100755
index 0000000..efb96c3
--- /dev/null
+++ b/squashfs/bin/bootstrap.sh
@@ -0,0 +1,68 @@
+#!/bin/busybox sh
+
+#mount the squashfs + unionfs and boot into it
+
+move_mounts() {
+  local base_mounts="/sys /proc /dev"
+  local newroot_mnt="$1"
+  for mnt in $base_mounts; do
+    mkdir -p "$newroot_mnt$mnt"
+    mount -n -o move "$mnt" "$newroot_mnt$mnt"
+  done
+}
+
+boot_dir() {
+  local target="$1"
+
+  echo "moving mounts to newroot"
+  move_mounts $target
+
+  echo "switching root"
+  mkdir -p $target/oldroot
+  pivot_root $target $target/oldroot
+
+  /bin/bash -c "mount -o bind /oldroot/lib/modules /lib/modules"
+  exec /sbin/init < "$TTY1" >> "$TTY1" 2>&1
+}
+
+mount_squashfs() {
+  mkdir -p /lib/modules /mnt/root_squashfs
+  mount /root.squashfs /mnt/root_squashfs
+  mount -o bind /mnt/root_squashfs/lib/modules /lib/modules
+}
+
+#based on https://github.com/rpodgorny/unionfs-fuse/blob/master/examples/S01a-unionfs-live-cd.sh
+mount_unionfs() {
+  local chroot_path="/tmp/unionfs"
+  local data_path="/data"
+  local mountpoint="/newroot"
+  local squashfs_path="/mnt/root_squashfs"
+
+  local fuse_options="-o allow_other,suid,dev"
+  local unionfs_options="-o cow,chroot=$chroot_path,max_files=32768"
+
+  mkdir -p $data_path 
+  mkdir -p $mountpoint
+  mkdir -p $chroot_path/root
+  mkdir -p $chroot_path/rw
+  
+  mount -o bind $squashfs_path $chroot_path/root
+  mount -o bind $data_path $chroot_path/rw
+
+  modprobe fuse
+  unionfs $fuse_options $unionfs_options /root=RO:/rw=RW /newroot
+}
+
+main() {
+  echo "mounting squashfs"
+  mount_squashfs
+
+  echo "mounting unionfs"
+  mount_unionfs
+
+  echo "booting unionfs"
+  boot_dir /newroot
+}
+
+main "$@"
+sleep 1d
diff --git a/squashfs/bin/init b/squashfs/bin/init
new file mode 100755
index 0000000..2e16afc
--- /dev/null
+++ b/squashfs/bin/init
@@ -0,0 +1,29 @@
+#!/bin/busybox sh
+
+#original: https://chromium.googlesource.com/chromiumos/platform/initramfs/+/refs/heads/main/factory_shim/init
+
+detect_tty() {
+  if [ -f "/bin/frecon-lite" ]; then
+    export TTY1="/dev/pts/0"
+    export TTY2="/dev/pts/1"
+  else
+    export TTY1="/dev/tty1"
+    export TTY2="/dev/tty2"
+  fi
+}
+
+setup_environment() {
+  # Install additional utility programs.
+  /bin/busybox --install /bin || true
+}
+
+main() {
+  setup_environment
+  detect_tty
+  # In case an error is not handled by bootstrapping, stop here
+  # so that an operator can see installation stop.
+  exec bootstrap.sh < "$TTY1" >> "$TTY1" 2>&1 || sleep 1d
+}
+
+main "$@"
+exit 1
\ No newline at end of file

From c0daaf71fa7b7b8018856083892bae863a3886ef Mon Sep 17 00:00:00 2001
From: ading2210 <ading2019@gmail.com>
Date: Fri, 22 Dec 2023 19:15:24 -0800
Subject: [PATCH 6/7] more build script bugfixes

---
 build.sh                   | 9 ++-------
 build_squashfs.sh          | 5 ++---
 patch_rootfs.sh            | 2 +-
 rootfs/opt/setup_rootfs.sh | 3 +++
 4 files changed, 8 insertions(+), 11 deletions(-)

diff --git a/build.sh b/build.sh
index 842ffe4..10ec5ca 100755
--- a/build.sh
+++ b/build.sh
@@ -58,6 +58,8 @@ echo "extracting data from kernel"
 initramfs_dir=/tmp/shim_initramfs
 rm -rf $initramfs_dir
 extract_initramfs $kernel_dir/kernel.bin $kernel_dir $initramfs_dir
+umount $shim_rootfs
+losetup -d $shim_loop
 
 echo "patching initramfs"
 patch_initramfs $initramfs_dir
@@ -75,16 +77,9 @@ image_loop=$(create_loop ${output_path})
 echo "creating partitions on the disk image"
 create_partitions $image_loop "${kernel_dir}/kernel.bin"
 
-echo "mounting the original shim rootfs"
-shim_rootfs="/tmp/shim_rootfs"
-make_mountable "${shim_loop}p3"
-safe_mount "${shim_loop}p3" $shim_rootfs
-
 echo "copying data into the image"
 populate_partitions $image_loop $initramfs_dir $rootfs_dir
 
 echo "cleaning up loop devices"
-umount $rootfs_dir
-losetup -d $shim_loop
 losetup -d $image_loop
 echo "done"
\ No newline at end of file
diff --git a/build_squashfs.sh b/build_squashfs.sh
index edd3d36..e3a7d6b 100755
--- a/build_squashfs.sh
+++ b/build_squashfs.sh
@@ -73,9 +73,8 @@ echo "extracting initramfs from kernel (this may take a while)"
 extract_initramfs $kernel_dir/kernel.bin $kernel_dir $rootfs_dir
 rm -rf $rootfs_dir/init
 
-echo "mounting shim"
-make_mountable "${shim_loop}p3"
-safe_mount "${shim_loop}p3" $shim_rootfs
+echo "removeing shim loop device"
+losetup -d $shim_loop
 
 echo "compressing old rootfs"
 mksquashfs $old_dir $root_squashfs -noappend -comp gzip
diff --git a/patch_rootfs.sh b/patch_rootfs.sh
index 8e85ca9..1aca979 100755
--- a/patch_rootfs.sh
+++ b/patch_rootfs.sh
@@ -7,7 +7,7 @@ if [ "$DEBUG" ]; then
   set -x
 fi
 
-. ./build_image.sh
+. ./image_utils.sh
 
 print_help() {
   echo "Usage: ./patch_rootfs.sh shim_path reco_path rootfs_dir"
diff --git a/rootfs/opt/setup_rootfs.sh b/rootfs/opt/setup_rootfs.sh
index 6fda0a7..6e69f41 100755
--- a/rootfs/opt/setup_rootfs.sh
+++ b/rootfs/opt/setup_rootfs.sh
@@ -24,6 +24,9 @@ Pin: origin ${custom_repo_domain}
 Pin-Priority: 1001
 END
 
+#fix name servers
+echo "nameserver 1.1.1.1" > /etc/resolv.conf
+
 #install the patched systemd
 apt-get install -y ca-certificates
 apt-get update

From 3de0b9aa55d3f09719ab9fca05e547b07114218e Mon Sep 17 00:00:00 2001
From: ading2210 <ading2019@gmail.com>
Date: Tue, 26 Dec 2023 03:33:28 +0000
Subject: [PATCH 7/7] improve documentation

---
 README.md                  | 8 ++++++--
 build.sh                   | 3 +--
 build_rootfs.sh            | 1 +
 rootfs/opt/setup_rootfs.sh | 3 ---
 4 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/README.md b/README.md
index e607503..622e5f5 100644
--- a/README.md
+++ b/README.md
@@ -33,9 +33,10 @@ Driver support depends on the device you are using shimboot on. This list is for
 - Bluetooth
 - Zram
 - Wifi
+- Booting a squashfs
 
 ### What Doesn't Work:
-- Audio
+- Audio (due to a firmware bug)
 - Suspend (disabled by the kernel)
 - Swap (disabled by the kernel)
 
@@ -91,11 +92,14 @@ Driver support depends on the device you are using shimboot on. This list is for
 Using any Linux distro is possible, provided that you apply the [proper patches](https://github.com/ading2210/chromeos-systemd) to systemd and recompile it. Most distros have some sort of bootstrapping tool that allows you to install it to a directory on your host PC. Then, you can just pass that rootfs dir into `build.sh`.
 
 #### How can I install a desktop environment other than XFCE?
-Simply edit `rootfs/opt/setup_rootfs.sh`, and change the line after the `#install desktop` comment. By default, this is set to install XFCE using the `task-xfce-desktop` package, but you can change this to install whatever you want.
+You can pass another argument to the `build_rootfs.sh` script, like this: `sudo ./build_rootfs.sh data/rootfs bookworm "task-lxde-desktop"`. The third argument is a list of packages that will be installed in the place of XFCE. 
 
 #### Will this prevent me from using Chrome OS normally?
 Shimboot does not touch the internal storage at all, so you will be able to use Chrome OS as if nothing happened. However, if you are on an enterprise enrolled device, booting Chrome OS again will force a powerwash due to the attempted switch into developer mode.
 
+#### Can I unplug the USB drive while using Debian?
+By default, this is not possible. However, you can simply copy your Debian rootfs onto your internal storage by first using `fdisk` to repartition it, using `dd` to copy the partition, and `resize2fs` to have it take up the entire drive. In the future, loading the OS to RAM may be supported, but this isn't a priority at the moment.
+
 ## Copyright:
 Shimboot is licensed under the [GNU GPL v3](https://www.gnu.org/licenses/gpl-3.0.txt). Unless otherwise indicated, all code has been written by me, [ading2210](https://github.com/ading2210).
 
diff --git a/build.sh b/build.sh
index 10ec5ca..40f9385 100755
--- a/build.sh
+++ b/build.sh
@@ -58,7 +58,6 @@ echo "extracting data from kernel"
 initramfs_dir=/tmp/shim_initramfs
 rm -rf $initramfs_dir
 extract_initramfs $kernel_dir/kernel.bin $kernel_dir $initramfs_dir
-umount $shim_rootfs
 losetup -d $shim_loop
 
 echo "patching initramfs"
@@ -66,7 +65,7 @@ patch_initramfs $initramfs_dir
 
 echo "creating disk image"
 rootfs_size=$(du -sm $rootfs_dir | cut -f 1)
-rootfs_part_size=$(($rootfs_size * 11 / 10))
+rootfs_part_size=$(($rootfs_size * 12 / 10))
 #create a 20mb bootloader partition
 #rootfs partition is 20% larger than its contents
 create_image $output_path 20 $rootfs_part_size
diff --git a/build_rootfs.sh b/build_rootfs.sh
index 4669ab7..d1dc2b6 100755
--- a/build_rootfs.sh
+++ b/build_rootfs.sh
@@ -44,6 +44,7 @@ packages="${3-'task-xfce-desktop'}"
 
 debootstrap --arch amd64 $release_name $rootfs_dir http://deb.debian.org/debian/
 cp -ar rootfs/* $rootfs_dir
+cp /etc/resolv.conf $rootfs_dir/etc/resolv.conf
 
 chroot_mounts="proc sys dev run"
 for mountpoint in $chroot_mounts; do
diff --git a/rootfs/opt/setup_rootfs.sh b/rootfs/opt/setup_rootfs.sh
index 6e69f41..6fda0a7 100755
--- a/rootfs/opt/setup_rootfs.sh
+++ b/rootfs/opt/setup_rootfs.sh
@@ -24,9 +24,6 @@ Pin: origin ${custom_repo_domain}
 Pin-Priority: 1001
 END
 
-#fix name servers
-echo "nameserver 1.1.1.1" > /etc/resolv.conf
-
 #install the patched systemd
 apt-get install -y ca-certificates
 apt-get update