Luks Cryptmount - Resize encrypted LVM volume

luks_cryptmount_resize.sh

#!/bin/bash

set -eE -o pipefail

# to create such a volume - use: https://gist.github.com/NiceRath/c794caa26a28fc90fc628a047648722b

if [ $# -lt 3 ]
then
  cat << EOF
You must provide:
1. -> the vg-name as argument 1
2. -> the lv-name as argument 2 and
3. -> the resize amout as arugment 3 (p.e. '100GB')

Available volumes:"
EOF
  lvscan
  exit 1
fi

set -u

VG_NAME=$1
LV_NAME=$2
RESIZE_AMOUNT=$3

MAPPER_DIR='/dev/mapper'
LV_DEV="$MAPPER_DIR/$VG_NAME-$LV_NAME"
ENC_LV_NAME="crypt-$VG_NAME-$LV_NAME"
LV_DEV_ENC="$MAPPER_DIR/$ENC_LV_NAME"
KEY_DIR='<PATH-TO-KEY-DIR>'
GPG_FILE="${KEY_DIR}/<GPG-PASSPHRASE-FILE>"
KEY_HOST='<KEY-HOST>'
KEY_HOST_KEY_DIR='<KEY-HOST-DIR>'
KEY_SSH_USER='<KEY-HOST-USER>'
KEY_SSH_PORT='<KEY-HOST-SSH-PORT>'
KEY_SSH_KEY='<KEY-HOST-USER-SSH-KEY>'

# resize lvm lv
lvresize /dev/$VG_NAME/$LV_NAME --size +$RESIZE_AMOUNT

# resize crypto container
UUID=`cryptsetup luksUUID $LV_DEV`

KEY_FILE="$KEY_HOST_KEY_DIR/$UUID.key.asc"
KEY=`ssh -p $KEY_SSH_PORT -i $KEY_SSH_KEY $KEY_SSH_USER@$KEY_HOST "cat $KEY_FILE" | gpg --batch --yes --ignore-mdc-error --no-mdc-warning --no-tty --passphrase-file $GPG_FILE --quiet --decrypt`
echo $KEY | tr -d "\n" | cryptsetup resize $LV_DEV_ENC --key-file=-

# resize file system
resize2fs $LV_DEV_ENC

# output current lv's
echo "Resizing of volume $LV_DEV_ENC finished; Current size:"
lvscan