#!/system/bin/sh

LOGFILE=/cache/magisk.log
IMG=/data/magisk.img

MOUNTPOINT=/magisk

COREDIR=$MOUNTPOINT/.core

TMPDIR=/dev/magisk
DUMMDIR=$TMPDIR/dummy
MIRRDIR=$TMPDIR/mirror
MOUNTINFO=$TMPDIR/mnt

# Use the included busybox for maximum compatibility and reliable results
# e.g. we rely on the option "-c" for cp (reserve contexts), and -exec for find
TOOLPATH=/data/busybox
BINPATH=/data/magisk

export OLDPATH=$PATH
export PATH=$TOOLPATH:$OLDPATH

# Default permissions
umask 022


log_print() {
  echo "$1"
  echo "$1" >> $LOGFILE
  log -p i -t Magisk "$1"
}

mktouch() {
  mkdir -p ${1%/*} 2>/dev/null
  if [ -z "$2" ]; then
    touch "$1" 2>/dev/null
  else
    echo "$2" > "$1" 2>/dev/null
  fi
}

unblock() {
  touch /dev/.magisk.unblock
  exit
}

run_scripts() {
  BASE=$MOUNTPOINT
  for MOD in $BASE/* ; do
    if [ ! -f $MOD/disable ]; then
      if [ -f $MOD/$1.sh ]; then
        chmod 755 $MOD/$1.sh
        chcon "u:object_r:system_file:s0" "$MOD/$1.sh"
        log_print "$1: $MOD/$1.sh"
        sh $MOD/$1.sh
      fi
    fi
  done
}

loopsetup() {
  LOOPDEVICE=
  for DEV in `ls /dev/block/loop*`; do
    if losetup $DEV $1; then
      LOOPDEVICE=$DEV
      break
    fi
  done
}

target_size_check() {
  e2fsck -p -f $1
  curBlocks=`e2fsck -n $1 2>/dev/null | cut -d, -f3 | cut -d\  -f2`;
  curUsedM=$((`echo "$curBlocks" | cut -d/ -f1` * 4 / 1024));
  curSizeM=$((`echo "$curBlocks" | cut -d/ -f2` * 4 / 1024));
  curFreeM=$((curSizeM - curUsedM));
}

travel() {
  cd $TRAVEL_ROOT/$1
  if [ -f .replace ]; then
    rm -rf $MOUNTINFO/$1
    mktouch $MOUNTINFO/$1 $TRAVEL_ROOT
  else
    for ITEM in * ; do
      if [ ! -e /$1/$ITEM ]; then
        # New item found
        # If we are in a higher level, delete the lower levels
        rm -rf $MOUNTINFO/dummy/$1
        # Mount the dummy parent
        mktouch $MOUNTINFO/dummy/$1

        if [ -d $ITEM ]; then
          # Create new dummy directory and mount it
          mkdir -p $DUMMDIR/$1/$ITEM
          mktouch $MOUNTINFO/$1/$ITEM $TRAVEL_ROOT
        elif [ -L $ITEM ]; then
          # Symlinks are small, copy them
          mkdir -p $DUMMDIR/$1 2>/dev/null
          cp -afc $ITEM $DUMMDIR/$1/$ITEM
        else
          # Create new dummy file and mount it
          mktouch $DUMMDIR/$1/$ITEM
          mktouch $MOUNTINFO/$1/$ITEM $TRAVEL_ROOT
        fi
      else
        if [ -d $ITEM ]; then
          # It's an directory, travel deeper
          (travel $1/$ITEM)
        elif [ ! -L $ITEM ]; then
          # Mount this file
          mktouch $MOUNTINFO/$1/$ITEM $TRAVEL_ROOT
        fi
      fi
    done
  fi
}

clone_dummy() {
  for ITEM in $MIRRDIR$1/* ; do
    REAL=${ITEM#$MIRRDIR}
    if [ -d $MOUNTINFO$REAL ]; then
      # Need to clone deeper
      mkdir -p $DUMMDIR$REAL
      (clone_dummy $REAL)
    else
      if [ -L $ITEM ]; then
        # Copy original symlink
        cp -afc $ITEM $DUMMDIR$REAL
      else
        if [ -d $ITEM ]; then
          mkdir -p $DUMMDIR$REAL
        else
          mktouch $DUMMDIR$REAL
        fi
        # Mount the mirror if not module item
        [ ! -e $MOUNTINFO$REAL ] && mktouch $MOUNTINFO/mirror$REAL
      fi
    fi
  done
}

bind_mount() {
  if [ -e $1 -a -e $2 ]; then
    mount -o bind $1 $2
    if [ $? -eq 0 ]; then 
      log_print "Mount: $1"
    else 
      log_print "Mount Fail: $1"
    fi 
  fi
}

merge_image() {
  if [ -f $1 ]; then
    log_print "$1 found"
    if [ -f $IMG ]; then
      log_print "$IMG found, attempt to merge"

      # Handle large images
      target_size_check $1
      MERGEUSED=$curUsedM
      target_size_check $IMG
      if [ "$MERGEUSED" -gt "$curFreeM" ]; then
        NEWDATASIZE=$((((MERGEUSED + curUsedM) / 32 + 2) * 32))
        log_print "Expanding $IMG to ${NEWDATASIZE}M..."
        resize2fs $IMG ${NEWDATASIZE}M
      fi

      # Start merging
      mkdir /cache/data_img
      mkdir /cache/merge_img

      # setup loop devices
      loopsetup $IMG
      LOOPDATA=$LOOPDEVICE
      log_print "$LOOPDATA $IMG"

      loopsetup $1
      LOOPMERGE=$LOOPDEVICE
      log_print "$LOOPMERGE $1"

      if [ ! -z $LOOPDATA -a ! -z $LOOPMERGE ]; then
        # if loop devices have been setup, mount images
        OK=false
        mount -t ext4 -o rw,noatime $LOOPDATA /cache/data_img && \
        mount -t ext4 -o rw,noatime $LOOPMERGE /cache/merge_img && \
        OK=true

        if $OK; then
          # Merge (will reserve selinux contexts)
          cd /cache/merge_img
          for MOD in *; do
            if [ "$MOD" != "lost+found" ]; then
              log_print "Merging: $MOD"
              rm -rf /cache/data_img/$MOD
            fi
          done
          cp -afc . /cache/data_img
          log_print "Merge complete"
          cd /
        fi

        umount /cache/data_img
        umount /cache/merge_img
      fi

      losetup -d $LOOPDATA
      losetup -d $LOOPMERGE

      rmdir /cache/data_img
      rmdir /cache/merge_img
    else 
      log_print "Moving $1 to $IMG "
      mv $1 $IMG
    fi
    rm -f $1
  fi
}

case $1 in
  post-fs )
    mv $LOGFILE /cache/last_magisk.log
    touch $LOGFILE
    chmod 644 $LOGFILE

    # No more cache mods!
    # Only for multirom!

    log_print "** Magisk post-fs mode running..."

    # Cleanup legacy stuffs...
    rm -rf /cache/magisk /cache/magisk_merge /cache/magiskhide.log

    if [ -d /cache/magisk_mount ]; then
      log_print "* Mounting cache files"
      find /cache/magisk_mount -type f 2>/dev/null | while read ITEM ; do
        chmod 644 $ITEM
        chcon "u:object_r:system_file:s0" $ITEM
        TARGET=${ITEM#/cache/magisk_mount}
        bind_mount $ITEM $TARGET
      done
    fi

    unblock
    ;;

  post-fs-data )
    # /data not mounted yet
    ! mount | grep " /data " && unblock
    mount | grep " /data " | grep "tmpfs" && unblock

    # Don't run twice
    if [ "`getprop magisk.restart_pfsd`" != "1" ]; then

      log_print "** Magisk post-fs-data mode running..."

      # Cache support
      if [ -d "/cache/data_bin" ]; then
        rm -rf $BINPATH $TOOLPATH
        mkdir -p $TOOLPATH
        mv /cache/data_bin $BINPATH
        chmod -R 755 $BINPATH $TOOLPATH
        $BINPATH/busybox --install -s $TOOLPATH
        ln -s $BINPATH/busybox $TOOLPATH/busybox
        # Prevent issues
        rm -f $TOOLPATH/su $TOOLPATH/sh
      fi

      mv /cache/stock_boot.img /data 2>/dev/null

      find $BINPATH -exec chcon -h "u:object_r:system_file:s0" {} \;
      find $TOOLPATH -exec chcon -h "u:object_r:system_file:s0" {} \;
      chmod -R 755 $BINPATH $TOOLPATH

      # Live patch sepolicy
      $BINPATH/sepolicy-inject --live -s su

      # Multirom functions should go here, not available right now
      MULTIROM=false

      # Image merging
      chmod 644 $IMG /cache/magisk.img /data/magisk_merge.img 2>/dev/null
      merge_image /cache/magisk.img
      merge_image /data/magisk_merge.img

      # Mount magisk.img
      [ ! -d $MOUNTPOINT ] && mkdir -p $MOUNTPOINT
      if ! mount | grep $MOUNTPOINT; then
        loopsetup $IMG
        [ ! -z $LOOPDEVICE ] && mount -t ext4 -o rw,noatime $LOOPDEVICE $MOUNTPOINT
        if [ $? -ne 0 ]; then
          log_print "magisk.img mount failed, nothing to do :("
          unblock
        fi
      fi

      # Remove empty directories, legacy paths, symlinks, old temporary images
      find $MOUNTPOINT -type d -depth ! -path "*core*" -exec rmdir {} \; 2>/dev/null
      rm -rf $COREDIR/bin $COREDIR/dummy $COREDIR/mirror /data/magisk/*.img

      # Remove modules that is labeled to be removed
      for MOD in $MOUNTPOINT/* ; do
        if [ -f $MOD/remove ] || [ $MOD = zzsupersu ]; then
          log_print "Remove module: $MOD"
          rm -rf $MOD
        fi
      done

      # Unmount, shrink, remount
      if umount $MOUNTPOINT; then
        losetup -d $LOOPDEVICE
        target_size_check $IMG
        NEWDATASIZE=$(((curUsedM / 32 + 2) * 32))
        if [ "$curSizeM" -gt "$NEWDATASIZE" ]; then
          log_print "Shrinking $IMG to ${NEWDATASIZE}M..."
          resize2fs $IMG ${NEWDATASIZE}M
        fi
        loopsetup $IMG
        [ ! -z $LOOPDEVICE ] && mount -t ext4 -o rw,noatime $LOOPDEVICE $MOUNTPOINT
        if [ $? -ne 0 ]; then
          log_print "magisk.img mount failed, nothing to do :("
          unblock
        fi
      fi

      log_print "* Preparing modules"

      mkdir -p $DUMMDIR
      mkdir -p $MIRRDIR/system

      # Travel through all mods
      for MOD in $MOUNTPOINT/* ; do
        if [ -f $MOD/auto_mount -a -d $MOD/system -a ! -f $MOD/disable ]; then
          TRAVEL_ROOT=$MOD
          (travel system)
        fi
      done

      # Proper permissions for generated items
      find $TMPDIR -exec chcon -h "u:object_r:system_file:s0" {} \;

      # linker(64), t*box required for bin
      if [ -f $MOUNTINFO/dummy/system/bin ]; then
        cp -afc /system/bin/linker* /system/bin/t*box $DUMMDIR/system/bin/
      fi

      DISABLEHIDE=false

      for i in /system /system/lib /system/lib64 /system/vendor /system/vendor/lib /system/vendor/lib64; do
        [ -f $MOUNTINFO/dummy$1 ] && DISABLEHIDE=true && break
      done

      # Crash prevention!!
      $DISABLEHIDE && rm -f $COREDIR/magiskhide/enable 2>/dev/null

      # Remove crap folder
      rm -rf $MOUNTPOINT/lost+found
      
      # Start doing tasks

      # Stage 1
      log_print "* Stage 1: Mount system and vendor mirrors"
      SYSTEMBLOCK=`mount | grep " /system " | awk '{print $1}'`
      mkdir -p $MIRRDIR/system
      mount -o ro $SYSTEMBLOCK $MIRRDIR/system
      if [ `mount | grep -c " /vendor "` -ne 0 ]; then
        VENDORBLOCK=`mount | grep " /vendor " | awk '{print $1}'`
        mkdir -p $MIRRDIR/vendor
        mount -o ro $VENDORBLOCK $MIRRDIR/vendor
      else
        ln -s $MIRRDIR/system/vendor $MIRRDIR/vendor
      fi
      # Since mirrors always exist, we load libraries from mirrors
      LD_LIBRARY_PATH=$MIRRDIR/system/lib:$MIRRDIR/vendor/lib
      [ -d /system/lib64 ] LD_LIBRARY_PATH=$MIRRDIR/system/lib64:$MIRRDIR/vendor/lib64

      # Stage 2
      log_print "* Stage 2: Mount dummy skeletons"
      # Move dummy /system/vendor to /vendor for consistency
      mv -f $MOUNTINFO/dummy/system/vendor $MOUNTINFO/dummy/vendor 2>/dev/null
      mv -f $DUMMDIR/system/vendor $DUMMDIR/vendor 2>/dev/null
      find $MOUNTINFO/dummy -type f 2>/dev/null | while read ITEM ; do
        TARGET=${ITEM#$MOUNTINFO/dummy}
        ORIG=$DUMMDIR$TARGET
        (clone_dummy $TARGET)
        bind_mount $ORIG $TARGET
      done

      # Stage 3
      log_print "* Stage 3: Mount module items"
      find $MOUNTINFO/system -type f 2>/dev/null | while read ITEM ; do
        TARGET=${ITEM#$MOUNTINFO}
        ORIG=`cat $ITEM`$TARGET
        bind_mount $ORIG $TARGET
      done

      # Stage 4
      log_print "* Stage 4: Execute module scripts"
      run_scripts post-fs-data

      # Stage 5
      log_print "* Stage 5: Mount mirrored items back to dummy"
      find $MOUNTINFO/mirror -type f 2>/dev/null | while read ITEM ; do
        TARGET=${ITEM#$MOUNTINFO/mirror}
        ORIG=$MIRRDIR$TARGET
        bind_mount $ORIG $TARGET
      done

      # Bind hosts for Adblock apps
      if [ -f $COREDIR/hosts ]; then
        log_print "* Enabling systemless hosts file support"
        bind_mount $COREDIR/hosts /system/etc/hosts
      fi

      # Expose busybox
      if [ -f $COREDIR/busybox/enable ]; then
        log_print "* Enabling BusyBox"
        cp -afc /data/busybox/. $COREDIR/busybox
        cp -afc /system/xbin/. $COREDIR/busybox
        chmod -R 755 $COREDIR/busybox
        chcon -hR "u:object_r:system_file:s0" $COREDIR/busybox
        bind_mount $COREDIR/busybox /system/xbin
      fi

      # Restart post-fs-data if necessary (multirom)
      $MULTIROM && setprop magisk.restart_pfsd 1

    fi
    unblock
    ;;

  service )
    # Version info
    MAGISK_VERSION_STUB
    log_print "** Magisk late_start service mode running..."
    run_scripts service

    # Magisk Hide
    if [ -f $COREDIR/magiskhide/enable ]; then
      log_print "* Removing tampered read-only system props"

      VERIFYBOOT=`getprop ro.boot.verifiedbootstate`
      FLASHLOCKED=`getprop ro.boot.flash.locked`
      VERITYMODE=`getprop ro.boot.veritymode`

      [ ! -z "$VERIFYBOOT" -a "$VERIFYBOOT" != "green" ] && \
      log_print "`$BINPATH/resetprop -v -n ro.boot.verifiedbootstate green`"
      [ ! -z "$FLASHLOCKED" -a "$FLASHLOCKED" != "1" ] && \
      log_print "`$BINPATH/resetprop -v -n ro.boot.flash.locked 1`"
      [ ! -z "$VERITYMODE" -a "$VERITYMODE" != "enforcing" ] && \
      log_print "`$BINPATH/resetprop -v -n ro.boot.veritymode enforcing`"

      mktouch $COREDIR/magiskhide/hidelist
      chmod -R 755 $COREDIR/magiskhide
      # Add Safety Net preset
      $COREDIR/magiskhide/add com.google.android.gms.unstable
      log_print "* Starting Magisk Hide"
      /data/magisk/magiskhide
    fi
    ;;

esac