#!/usr/local/bin/bash

# geli container mount and umount script
#=======================================

# script usage
script_usage=$(printf "%s\n" \
"mount: sudo $(basename "$0") mount -f container -k gelikey" \
"umount: sudo $(basename "$0") umount -f container")

# check to see if script was run as root
if [[ $UID -ne 0 ]]; then
  printf "%s\n" "$0 must be run as root using sudo" "$script_usage"
  exit 1
fi

# mount function
mount () {
    # group commands
    { 
    # container
    container="$1" && \
    # gelikey
    gelikey="$2" && \

    # mdconfig loopname from container
    loopdevice=$(mdconfig -lf "$container" | sed 's/[ \t]*$//')

    # eli filepath
    loopcrypt="/dev/${loopdevice}.eli"

    # mdconfig create vnode from container
    printf "%s\n" "+ mdconfig creating vnode for '$container'" && \
    loop=$(mdconfig -a -t vnode -f "$container") && \

    # geli attach key to vnode
    printf "%s\n" "+ geli attaching '$gelikey' key to '$container' file" && \
    geli attach -k "$gelikey" "$loop" && \

    # mdconfig loop device for container
    loopdevice=$(mdconfig -lf "$container" | sed 's/[ \t]*$//') && \

    # path to mdconfig eli file
    loopcrypt="/dev/${loopdevice}.eli" && \

    # zpool name from mdconfig eli file
    poolname=$(zdb -l "$loopcrypt" | awk -F\' '/[[:blank:]]name/ {print $2; exit;}') && \

    # zpool import pool
    printf "%s\n" "+ zpool importing '$poolname'" && \
    zpool import "$poolname" && \

    # mount point from zpool
    mountpoint=$(zfs get -H -o value mountpoint "$poolname") && \
    printf "%s\n" "+ '$poolname' mounted to '$mountpoint'";
    } || { mdconfig -du "$loopdevice" && exit; }
}

# umount function
umount () {
    # group commands
    {
    # container
    container="$1" && \

    # mdconfig loopname from container
    loopdevice=$(mdconfig -lf "$container" | sed 's/[ \t]*$//') && \

    # eli filepath
    loopcrypt="/dev/${loopdevice}.eli" && \

    # zpool name from eli file
    poolname=$(zdb -l "$loopcrypt" | awk -F\' '/[[:blank:]]name/ {print $2; exit;}') && \

    # zfs umount poolname
    printf "%s\n" "- zfs unmounting '$poolname'" && \
    zfs umount "$poolname" && \

    # zpool export poolname
    printf "%s\n" "- zpool exporting '$poolname'" && \
    zpool export "$poolname" && \
    sleep 1 && \

    # geli detach
    printf "%s\n" "- geli detaching '$loopcrypt'" && \
    geli detach "$loopcrypt" && \

    # mdconfig remove md file
    printf "%s\n" "- mdconfig clearing '$loopdevice'" && \
    mdconfig -du "$loopdevice" && \
    printf "%s\n" "- unmounted device";
    } || { printf "%s\n" 'container not mounted' && exit; }
}

# check if mount is first argument
# + 2nd argument shuld be -f for the file to mount
# + 3rd argument should be the path to the file to mount
# + 4th argunent should be -k for key
# + 5th argument should be the path to the keyfile

# check if umount is first argument
# + 2nd argument shuld be -f for the file to unmount
# + 3rd argument should be the path to the file to unmount

# check arguments
if [[ "$1" =~ ^mount$ && $# -eq 5 ]]; then
   # group commands
   {
   [[ "$2" =~ '-f' ]] && \
   [[ -f "$3" ]] && \
   [[ "$4" =~ '-k' ]] && \
   [[ -f "$5" ]];
   } || { printf "%s\n" "$script_usage" && exit; }
   # mount function pass conatainer and key to function
   mount "$3" "$5"
elif [[ "$1" =~ ^umount$ && $# -eq 3 ]]; then
   # group commands
   {
   [[ "$2" =~ '-f' ]] && \
   [[ -f "$3" ]];
   } || { printf "%s\n" "$script_usage" && exit; }
   # umount function pass container to function
   umount "$3"
else
   printf "%s\n" "$script_usage" 
fi