decrypt

#!/bin/bash
# Decrypt an gpg encrypt file.
# Name:
#   decrypt
#
# Usage:
#   decrypt gpgFile
#       gpgFile - encrypted file (encrypted using encrypt or gpg command)
#
# See also:
#   encrypt
#
# yaswant.pradhan
# -----------------------------------------------------------------------------

[ -z "$1" ] && echo -e "usage:\t${0##*/} <gpgfile>\n" && exit 1

Extn0=${1##*.}
Base0=${1%.*}

# validate gpg file extension
[[ "$Extn0" != 'gpg' ]] && { printf "%s\n" "$1 is not a gpg file"; exit 0; }

# does tar extraction required?
Extn1=${Base0##*.}
Base1=${Base0%.*}

# Validate existing file/directory
if [ -e "$Base1" ]; then
  printf "%s\n" "Warning: A file/dir with name '$Base1' already exists in path"
  read -rp "Would you like to continue/overwrite? y|N: " x
  [[ $x != y ]] && printf "Aborted." && exit 0
fi

# decrypt [and extract]
case $Extn1 in
  tar)
    printf "\n%s" "Extract dir '$Base1'..."
    gpg --decrypt "$1" 2>/dev/null | tar -x
    printf "done.\n"
    ;;
  tgz)
    printf "\n%s" "Extract dir '$Base1'..."
    gpg --decrypt "$1" 2>/dev/null | tar -xz
    printf "done.\n"
    ;;
  tbz|tbz2)
    printf "\n%s" "Extract dir '$Base1'..."
    gpg --decrypt "$1" 2>/dev/null | tar -xj
    printf "done.\n"
    ;;
  *)
    printf "\n%s" "Restore file '$Base0'..."
    gpg "$1" 2>/dev/null
    printf "done.\n"
    ;;
esac