remarvin.sh

#!/usr/bin/env bash

#export LD_PRELOAD=/opt/lib/librm2fb_client.so.1.0.1
CIPHER=/home/root/.local/share/remarkable-cipher
GOCRYPTFS=$(which gocryptfs)
LAUNCHER=xochitl
PATH=/home/root/go/bin:/opt/bin/go/bin:/opt/bin:/opt/sbin:/usr/local/bin:/usr/bin:/bin:/usr/local/sbin:/usr/sbin:/sbin
PLAIN=/home/root/.local/share/remarkable
LOCAL="/home/root/.local"
CONFIG="/home/root/.config/remarkable"
PAGECOUNT=0
export LAUNCHER=xochitl
export MESSAGEA=" "
export MESSAGEB=" "
set -o noglob

# Simple Application Script Functions
reset(){
  SCENE=("@fontsize 40")
}
add(){
  SCENE+=("@$*")
}
ui(){
  SCENE+=("$*")
}
display(){
  IFS=$(echo -en "\n\b")
  script=$(for line in ${SCENE[@]}; do echo $line; done)
  IFS=" "
  RESULT=$(echo ${script} | /opt/bin/simple 2> /dev/null)
}

# Auxiliary Functions
function buttonpress(){
  echo button pressed
  button="$(echo "${RESULT}" | sed 's/^selected:\s*//; s/\s* -.*$//' | xargs)"
  set +f
  case $button in
    "Profile-"*)
       echo Profile Button pressed
       mount_profile $button
       ;;
    "$LAUNCHER")
       systemctl start $LAUNCHER;
       exit 0
       ;;
    "Decrypt")
       scene_decrypt
       ;;
    "Encrypt Profile")
       scene_encrypt
       ;;
    "Undo Encryption")
       scene_undo_encrypt
       ;;
    "Add Profile")
       scene_addprofile
       ;;
    "Back")
       return 1
       ;;
    "Quit")
       exit 0
       ;;
    "Unmount")
       clean_environment
       ;;
    "More Profiles")
       export PAGECOUNT=$(( $PAGECOUNT + 1 ))
       ;;
    *)
       echo Any key pressed
       return 0
       ;;
  esac
  set -f
}
function ui_scroller(){
	pagelist=${@:$(( 1 + $PAGECOUNT * 4 )):4}
	if [[ ${#pagelist} == 0 ]]
	then
	  export PAGECOUNT=0
	  pagelist=${@:$(( 1 + $PAGECOUNT * 4 )):4}
	fi
        for i in $pagelist
          do
            ui button 150 next 800 150 $(basename $i)
          done
        if [[ $# > 4 ]]
        then
            ui button 150 next 800 150 "More Profiles"
        fi
}
function confirmation_dialog(){
	# This function will take a message as an argument, print it and require the user to confirm
	return
}
function mount_profile(){
       profile=$1
       check_mountpoint $LOCAL/share && umount /home/root/.local/share && export MESSAGEA="Profile unmounted." || export MESSAGEA="Error unmounting current profile"
       mount --bind /home/root/.local/$profile /home/root/.local/share
       if [[ -e /home/root/.local/share/remarkable-cipher ]] 
		then
			#systemctl start gocryptfs-gui.service
			#/opt/bin/gocryptfs-gui.sh
			echo "Profile appears to be encrypted"
			export MESSAGEA="Profile appears to be encrypted."
			export MESSAGEB="You should decrypt before starting xochitl."
		else
			echo "Profile appears not to be encrypted."
			export MESSAGEA="Profile appears not to be encrypted."
			export MESSAGEB="You may launch xochitl now."
       fi
}

# Scenes
function scene_main(){
while :;do
  reset
  add justify left

  ui label  150 150  800 150 remarvin
  set +f
  ui_scroller $LOCAL/Profile-*
  set -f
  #ui button 150 next 800 150 $LAUNCHER
  ui button 150 next 800 150 "Add Profile"
  ui button 150 next 800 150 $(encryption_button)
  ui button 150 next 800 150 Quit
  ui label 150 next 800 150 $MESSAGEA
  ui label 150 next 800 150 $MESSAGEB

  display
  buttonpress
done
}
function scene_addprofile(){
  reset
  add justify left
  ui label  150 150  800 150 "remarvin - Add Profile"
  ui label  150 next  800 150 "Please enter Name for new Profile"
  ui textinput  150 next  800 150 
  ui label  150 next  800 150 
  ui button  150 next  800 150 "Back"
  display||return
  buttonpress||return
  NEWNAME="$(echo "${RESULT}" | awk -F ": " '{print $3}')"
  [[ $NEWNAME == "" ]]&&return
  mkdir -p /home/root/.local/Profile-$NEWNAME/remarkable
  mount_profile Profile-$NEWNAME
}
function scene_ask_reset(){
        reset
        add justify left

        ui label  150 150  800 150 remarvin
        ui label 150 next 800 150 "A profile is already mounted."
        ui label 150 next 800 150 "Shall we unmount all profiles?"
        ui button 150 next 800 150 "Unmount"
        ui button 150 next 800 150 "Ignore"
        ui button 150 next 800 150 "Quit"

        display
        buttonpress
}
function scene_warning(){
  reset
  add justify left

  ui label 50 150 800 150 remarvin has not been set up properly
  ui label 50 next 800 150 or you have already mounted a profile.  
  ui label 50 next 800 150 Please refer to 
  ui label 50 next 800 150 https://github.com/plan5/remarvin/README.md 
  ui button 150 next 800 150 Quit

  display
  buttonpress
}
function scene_xochitl-running(){
  reset
  add justify left

  ui label 50 150 800 150 xochitl is currently running
  ui label 50 next 800 150 Please quit xochitl 
  ui label 50 next 800 150 then run again or check
  ui label 50 next 800 150 https://github.com/plan5/remarvin
  ui button 150 next 800 150 Quit

  display
  buttonpress
}
function scene_decrypt(){
        reset
        add justify left

        # Add Input field
        ui label 50 160 1300 100 Enter password above, then press \'done\'
  ui button  150 next  800 150 "Back"
        ui label 50 next 1300 100 $MESSAGEA
        ui textinput 50 50 1300 100

        display||return
        password_decrypt
}
function scene_encrypt(){
	if run_gocryptfs_checks 
	then
		reset
		add justify left

		# Add Input field
		ui textinput 50 50 1300 100
		ui label 50 160 1300 100 You need to specify a password.
		ui label 50 next 1300 100 Enter password above, then press \'done\'
		ui button 50 next 1300 100 "Back"

		display||return 
		password_encrypt && MESSAGEA="Successfully encrypted!" && MESSAGEB="You will need the password next time."
		return 0
	else
		reset
		add justify left

		# Add Input field
		ui label 50 160 1300 100 Error: Not all required tools are installed.
		ui button 50 next 1300 100 Go back

		display
		return 0
	fi
}
function scene_undo_encrypt(){
	reset
	add justify left

	# Add Input field
	ui label 50 160 1300 100 You are about to undo encryption
	ui label 50 next 1300 100 on your selected profile.
	ui label 50 next 1300 100 
	ui label 50 next 1300 100 Are you sure you want to proceed?
	ui label 50 next 1300 100 Type \"remove encryption\" below
	ui label 50 next 1300 100 
	ui button 50 next 1300 100 "Back"
	ui textinput 50 50 1300 100


	display||return
        message="$(echo "${RESULT}" | awk -F ": " '{print $3}')"
	[[ $message == "remove encryption" ]] && undo_encrypt
	return 0
}

# Initial Setup functions and scenes
function scene_setup(){
  reset
  add justify left 
  ui label  150 150  800 150 remarvin
  ui label 150 next 800 150 
  ui label 150 next 800 150  "Welcome!"
  ui label 150 next 800 150 
  ui label 150 next 800 150  "remarvin has not been set up yet."
  ui label 150 next 800 150 
  ui label 150 next 800 150  "ATTENTION: This Code is not well tested."
  ui label 150 next 800 150 
  ui label 150 next 800 150  "It should work but make sure to have a backup of"
  ui label 150 next 800 150  "/home/root outside the device, e.g. using scp."
  ui label 150 next 800 150  
  ui label 150 next 800 150  "DO NOT USE THIS IF YOU ARE REGISTERED TO THE CLOUD!"
  ui label 150 next 800 150  "Currently, the user configuration remains the same across"
  ui label 150 next 800 150  "profiles. This will mess with cloud synchronization."
  ui label 150 next 800 150 
  ui label 150 next 800 150  "This will restructure your home directory."
  ui label 150 next 800 150  "Run remarvin_remove.sh to undo."
  ui label 150 next 800 150 
  ui label 150 next 800 150  "Do you want to run the setup"?
  ui label 150 next 800 150 
  ui button 150 next 800 150  "Yes"
  ui label 150 next 800 150 
  ui button 150 next 800 150  "No"

  display
  echo $RESULT
  [[ $RESULT == "selected: Yes" ]] && echo "Asking confirmation" && confirm_prepare || exit 0
}
function confirm_prepare(){
  reset
  add justify left
  ui label  150 150  800 150 remarvin
  ui label 150 next 800 150 "Do you understand that you are about to make changes to your"
  ui label 150 next 800 150 "system that may lead to data loss or other unforeseen behavior and that"
  ui label 150 next 800 150 "you are doing this on your own responsibility?"
  ui label 150 next 800 150 
  ui button 150 next 800 150  "Yes"
  ui label 150 next 800 150 
  ui button 150 next 800 150  "No, abort!"

  display
  echo $RESULT
  [[ $RESULT == "selected: Yes" ]] && setup_profiles || exit 0
}
function prepare_abort(){
	echo "Goodbye."
}
function setup_profiles(){
    systemctl stop xochitl
    kill $(pgrep xochitl)
    
    cd "$LOCAL"

    # In the future, the config file will be per-profile
    # This needs to be thoroughly tested first.
    #mv "$CONFIG/xochitl.conf" "share/"
    #ln "$LOCAL/share/xochitl.conf" "$CONFIG/xochitl.conf"
    
    mkdir Profile-Main && mv share/remarkable Profile-Main||exit 1
    mkdir -p share/remarkable/xochitl

    # This should add a warning file but isn't working right now.
    #touch ./share/xochitl/readonly.metadata
    #echo '{\
    #"deleted": false,\
    #"lastModified": "1657376536026",\
    #"lastOpened": "1657376049165",\
    #"lastOpenedPage": 0,\
    #"metadatamodified": false,\
    #"modified": true,\
    #"parent": "",\
    #"pinned": false,\
    #"synced": false,\
    #"type": "DocumentType",\
    #"version": 0,\
    #"visibleName": "Warning: Read Only"\
    #}' > ./share/xochitl/readonly.metadata

    echo "This directory was set up for multiple profiles using remarvin.\n\
    Run remarvin_remove.sh to undo" > share/remarvin

    # Set immutable attribute to placeholder files in mountpoint
    chattr -R +i share/remarkable share/remarvin
    
}

# Encryption functions
function password_encrypt(){
        newpass="$(echo "${RESULT}" | awk -F ": " '{print $3}')"
	[[ $newpass == "" ]]&&return 1
	cd $LOCAL/share/
	mv remarkable remarkable-tmp
	mkdir remarkable remarkable-cipher
	echo $newpass|gocryptfs -init remarkable-cipher
	echo $newpass|gocryptfs remarkable-cipher remarkable
	mv remarkable-tmp/* remarkable &&\
                rm -r remarkable-tmp
}
function undo_encrypt(){
        echo running undo_encrypt
	# This function assumes that the directory is already mounted and decrypted. The corresponding scene should take care of that.
	kill $(pgrep xochitl)
	cd $LOCAL/share/
	mkdir remarkable-tmp
	mv remarkable/* remarkable-tmp/
	fusermount -u remarkable &&\
            chattr -R -i remarkable &&\
            rm -r remarkable remarkable-cipher &&\
            mv remarkable-tmp remarkable
}
function encryption_button(){
	if check_mountpoint $LOCAL/share/remarkable > /dev/null
	then
		echo -n Undo Encryption
	elif [ -d /home/root/.local/share/remarkable-cipher ] 
        then
		echo -n Decrypt
	elif check_mountpoint $LOCAL/share > /dev/null
	then
		echo -n Encrypt Profile
	else
		echo -n ""
	fi
}

# Mounting and decryption functions
function clean_environment(){
        #Unmount share
        umount /home/root/.local/share/remarkable
        umount /home/root/.local/share
}
function check_xochitl(){
	pgrep xochitl
}
function check_mountpoint(){
        mount | grep $@
}
function run_gocryptfs_checks(){
  # Check if gocryptfs is in PATH
  which $GOCRYPTFS||return 1
  # Check if fusermount in PATH 
  which fusermount||return 1
  # All good? Return 0
  return 0
}
function password_decrypt(){
  #id="$(echo "${RESULT}" | awk -F ": " '{print $2}')"
  message="$(echo "${RESULT}" | awk -F ": " '{print $3}')"
  export password="${message}"
  decrypt && return 0 || return 1
}
function decrypt(){
	echo "$password"|nohup $GOCRYPTFS $CIPHER $PLAIN && export MESSAGEA="Successfully decrypted!" && MESSAGEB="You may start xochitl now." &&return 0
	export MESSAGEA="Error decrypting!"
	return 1
}


# If remarvin is not yet set up, run setup function.
[[ -f /home/root/.local/share/remarvin ]] || check_mountpoint $LOCAL/share || scene_setup

# If profile is already mounted, ask to unmount
check_xochitl && scene_xochitl-running
check_mountpoint $LOCAL/share && scene_ask_reset && clean_environment

# Check if marker file exists to know everything is right, then run main loop. Else print out warning.
if [[ -f /home/root/.local/share/remarvin ]];
	then 
		scene_main
	else
		scene_warning
fi