bashcrawl

#!/usr/bin/env bash
# If you are reading this, you have wandered out of bounds
# and are reading the code that drives the game.
#
#                    Congratulations!
#
# Learning Linux is all about curiosity, so read this code and see
# if you can figure out what it does. If you're feeling a little
# overwhelmed by the scope try reading some of the smaller scripts
# inside the game.

# Force this to be run as sudo
if [[ $(/usr/bin/id -u) -ne 0 ]]; then
    echo "This game must be run with sudo"
    exit
fi

if [ -z "${ID}" ]; then
    export ID=99
fi

usage() {
  cat << EOF
Usage: bashcrawl COMMAND

    start GAME-TYPE  
      Begins or resumes a new game session of the specified type.
      Valid type are Basic, Advanced, or Net

    remove GAME-TYPE
      Removes all the game data files for the specified type.
    
    help
      Prints this help message

EOF
}
TYPE=0
JAIL=".jail"
# Determine the number of arguments passed to the script
# If a number was passed update the user id for a (possibly)
# new game
if [ $# -ne 0 ]; then
  case $1 in
    start)
      if [ $# -eq 2 ]; then 
        case $2 in
          Basic)
            TYPE=0
            JAIL=".jail"
            ;;
          Advanced)
            TYPE=1
            JAIL=".adv_jail"
            ;;
          Net)
            TYPE=2
            JAIL=".net_jail"
            ;;
          *)
            echo "Unknown game type: $2"
            usage
            exit 1
            ;;
        esac
        printf ""
      else
        printf "You need to specify the game type (Basic, Advanced, Net)\n\n"
        usage
	      exit 0
      fi
      ;;
    remove)
       if [ $# -eq 2 ]; then 
        case $2 in
          Basic)
            printf "This will delete all of your current progress\nWould you like to continue?  y / n  "
            read RESP
            if [ "$RESP" = "y" -o "$RESP" = "Y" ]; then
              rm -rf .jail
              printf "Your previous progress has been removed\n"
              exit 0
            else
              printf "We are not deleting anything\n"
              exit 0
            fi
            ;;
          Advanced)
            printf "This will delete all of your current progress\nWould you like to continue?  y / n  "
            read RESP
            if [ "$RESP" = "y" -o "$RESP" = "Y" ]; then
              rm -rf .adv_jail
              printf "Your previous progress has been removed\n"
              exit 0
            else
              printf "We are not deleting anything\n"
              exit 0
            fi
            ;;
          Net)
            printf "This will delete all of your current progress\nWould you like to continue?  y / n  "
            read RESP
            if [ "$RESP" = "y" -o "$RESP" = "Y" ]; then
              rm -rf .net_jail
              printf "Your previous progress has been removed\n"
              exit 0
            else
              printf "We are not deleting anything\n"
              exit 0
            fi
            ;;
          *)
            echo "Unknown game type: $2"
            usage
            exit 1
            ;;
        esac
              else
        printf "\nYou need to specify the game type (Basic, Advanced, Net)\n\n"
        usage
        exit 0
      fi
      ;;
    help)
      usage
      exit 0
      ;;
    *)
      echo "Unknown option: $1"
      usage
      exit 1
      ;;
    esac
else
  usage
  exit 0
fi

# This will catch any errors that are thrown by the script
# as well as catch an exit condition to restore the terminal
# to normal
trap cleanup SIGINT SIGTERM ERR EXIT

cleanup() {
    trap - SIGINT SIGTERM ERR EXIT
    # script cleanup
    # restore the old HOME variable
    export HOME=$OLD_HOME
    if test $TYPE = 0; then
      # destroy all the folders for the game
      sudo rm -rf ./.jail/{bin,lib64,lib,dev,etc,usr,proc,sys,dev,var}
    elif test $TYPE = 1; then
      #cp .adv_jail/ 2>/dev/null
      # destroy all the folders for the game
      # umount .jail/{dev,proc,sys}/
      umount $JAIL/dev/random
      umount $JAIL/dev/urandom
      sudo rm -rf ./.adv_jail/{bin,lib64,lib,dev,etc,usr,proc,sys,dev,var}
    elif test $TYPE = 2; then
      #cp .net
      # destroy all the folders for the game
      # umount .jail/{dev,proc,sys}/
      for i in $(ls /run/netns); do
        umount $JAIL/run/netns/$i
      done
      umount $JAIL/run
      umount $JAIL/proc
      umount $JAIL
      umount $JAIL/dev/null
      sudo rm -rf ./.net_jail/{bin,lib64,lib,dev,etc,usr,proc,sys,dev,var,run}
      sudo ./.utilities/stop.sh
    fi
    echo Thanks for playing, come back soon
}
  
# Save off the original value of the HOME variable so we can 
# restore it once we're done.
export OLD_HOME=$HOME

# create the directories necessary for a chroot jail
# apropos(1), groff(1), less(1), manpath(1), nroff(1), troff(1), whatis(1)
mkdir -p $JAIL/{bin,lib64,lib,dev,etc,usr,proc,sys,dev,run,var,mnt}

# cp $(which bash) .jail/bin
cp ./.utilities/busybox $JAIL/bin/busybox
for i in $($JAIL/bin/busybox --list)
do
    ln -s /bin/busybox $JAIL/bin/$i
done
#cp /bin/{awk,wc,realpath,basename,cut,col,manpath,whatis,less,grotty,nroff,tbl,sh,perl,groff,troff,grops,man,mandb,apropos,bash,pwd,ls,cat,mv,cp,chmod,file,mkdir,sed,grep,rm,echo,touch,clear,env} .jail/bin/
# for i in $(ldd /bin/{awk,wc,realpath,basename,cut,col,manpath,whatis,less,grotty,nroff,tbl,sh,perl,groff,troff,grops,man,mandb,apropos,bash,pwd,ls,cat,mv,cp,chmod,file,mkdir,sed,grep,rm,echo,touch,clear,env} | sed "s/(.*)//; s/^ *//; s/ *$//; s/\/bin\/.*://; s/ => /=>/" | sort | uniq) 
cp $(which file) $JAIL/bin/
cp $(which bash) $JAIL/bin/
cp $(which ip) $JAIL/bin/    # need ip since busybox version doesn't have netns
cp $(which ping) $JAIL/bin/
cp $(which nc) $JAIL/bin/
cp $(which ss) $JAIL/bin/
# added strace for debug purposes, removed in production
# cp $(which strace) $JAIL/bin/
for i in $(ldd $JAIL/bin/{file,bash,ip,ping,nc,ss} | sed "s/(.*)//; s/^ *//; s/ *$//; s/\/bin\/.*://; s/ => /=>/" | sort | uniq) 
do
    i=$(echo $i | sed "s/.*=>//")
    if test -f "$i"; then
        cp --parents $i $JAIL
    fi
done


case $TYPE in
  0)

    # Set a new HOME environment variable.  When we open the new 
    # shell for the game it will pull from the bashrc in the new
    # HOME directory.
    export HOME=/room/tower/mainhall  
    if test -d $JAIL/room; then
      # room already exists so do nothing
      echo "Resuming your previous game, good luck!"
    else
      echo "Starting a new game"
      cp -r .room $JAIL/room
      cp ./.utilities/welcome_message .jail
      cp ./.utilities/.secrets.txt ${JAIL}${HOME}
    fi

    ;;
  1)
    export HOME=/gate
    touch $JAIL/dev/random
    touch $JAIL/dev/urandom
    mount --rbind /dev/random $JAIL/dev/random
    mount --rbind /dev/urandom $JAIL/dev/urandom
    if test -d $JAIL/gate; then
      # gate already exists so do nothing
      echo "Resuming your previous game, good luck!"
    else
      echo "Starting a new game"
      cp -r .gate $JAIL/gate
      cp ./.utilities/advanced_welcome_message $JAIL
      cp ./.utilities/.secrets.txt ${JAIL}${HOME}
    fi
    ;;
  2)
    export HOME="/crossroad/City/The_Royal_Byte/"
    if test -d $JAIL/crossroad; then
      echo "Resuming your previous game, good luck!"
    else
      echo "Starting a new game"
      cp -r .netroom $JAIL/crossroad
      cp ./.utilities/net_welcome_message $JAIL
      cp ./.utilities/start.sh $JAIL/.start.sh
      cp ./.utilities/.secrets.txt ${JAIL}${HOME}
    fi
    
    chmod +x $JAIL/.start.sh
    sudo $JAIL/.start.sh
    touch $JAIL/dev/null
    mount --rbind /dev/null $JAIL/dev/null
    mount --bind --make-private $JAIL $JAIL
    mount --bind /proc $JAIL/proc/
    mount --bind /run $JAIL/run/
    for i in $(ls /run/netns); do
      mount --rbind /run/netns/$i $JAIL/run/netns/$i
    done
    ;;
esac

# copy over stuff so man works
mkdir -p $JAIL/usr/share/man
tar -C $JAIL/usr/share/man -xvzf ./.utilities/catpages.tar.gz &>/dev/null

# copy over stuff so file works
cp -r --parents /etc/magic $JAIL
cp -r --parents /usr/share/misc/magic $JAIL
cp -r --parents /lib/terminfo $JAIL
cp  --parents /usr/share/misc/magic.mgc $JAIL

# copy over stuff so ip works
cp -r --parents /etc/iproute2 $JAIL

#mount --bind /var $JAIL/var/
#mount --bind /mnt $JAIL/mnt/
#mount --bind /dev $JAIL/dev/
#mount --bind /proc $JAIL/proc/
#mount --bind /run $JAIL/run/
#mount --make-shared $JAIL/run/
#mount --bind /sys $JAIL/sys
#cp -r /usr/libexec/man-db .jail/usr/libexec

sudo chroot $JAIL /bin/env -i ID="$ID" HOME="$HOME" TERM="$TERM" PS1='\$ ' ENV="$HOME/.bashrc" PATH=/bin /bin/bash