Service to decrypt all selected PDFs. This script is intended for use in an automator workflow. Files and folders selected should be passed in as arguments.

decrypt_pdfs_service.sh

#! /bin/sh

password=$(security 2> /dev/null find-generic-password -a login -s decrypt_pdfs -D "application password" -w)

set -e

decrypt_file () {
  source_file="$1"
  filename="$(basename "$source_file")"
  directory="$(dirname "$source_file")/decrypted"
  destination="$directory/$filename"
  mkdir -p "$directory"

  qpdf --decrypt --password="$password" "$source_file" "$destination"
}

for arg in "$@"; do

  if [[ -d $arg ]]; then
    for file in "$arg"/*.pdf; do
      decrypt_file "$file"
    done

  elif [[ -f $arg ]]; then
    decrypt_file "$arg"
  fi

done

See related: https://gist.github.com/faun/11390337