.. /*  
    * This file is part of the SavaPage project <https://www.savapage.org>.
    * Copyright (c) 2026 Datraverse B.V.
    * Author: Rijk Ravestein.
    *
    * SPDX-FileCopyrightText: (c) 2020 Datraverse B.V. <info@datraverse.com>
    * SPDX-License-Identifier: CC-BY-SA-4.0
    *
    * For more information, please contact Datraverse B.V. at this
    * address: info@datraverse.com
    */

.. _ch-pdfpgp-signature:

PDF/PGP Signature
-----------------

PDF/PGP verification can be configured with the following properties:

.. list-table:: PDF/PGP Signing Configuration Properties
   :width: 100%
   :header-rows: 1
   
   * - Configuration property
     - Description
   * - pdfpgp.verification.enable
     - | Set to ``Y`` or ``N`` (default), to enable/disable PDF/PGP verification. 
       | 
       | If enabled *and* the :ref:`OpenPGP Key Pair <ch-install-on-linux-openpgp-keys>` is present on the server,
       | users who have the :ref:`Privilege to Sign <ch-webapp-admin-user-group-edit-user-privileges>` can apply an
       | :ref:`OpenPGP Signature <ch-webapp-user-main-pdf-security>` when creating a PDF for :ref:`Download <ch-webapp-user-main-pdf-download>` or :ref:`Send <ch-webapp-user-main-pdf-send>`.
   * - pdfpgp.verification.host
     - | DNS host name of the Verification Service.
       | If blank, the IPv4 address of the SavaPage server is used.
   * - pdfpgp.verification.port
     - | Optional TCP/IP port of the Verification Service. 
       | Host and port are used to compose the URL:
       |
       | ``https://host[:port]/verify/pdf``
       |
       | See :ref:`Appendix <app-url-cheat-sheet>`.

See :ref:`Config Editor <ch-webapp-admin-options-advanced-config-editor>`
on how to enter these properties.

A signed PDF file has the |RST_BUTTON_VERIFY_3_DOTS| button and the |PRODUCT_NAME|
server's OpenPGP Fingerprint displayed at top of the first page. 
When the button is pressed, the :ref:`Verification Web App <ch-pdfpgp-verification-webapp>` opens.


.. figure:: ../images/manual/screenshots/user/sp-pdfpgp-verify-link.png
   :width: 400
   
   PDF/PGP Verify Link


Also, the signed PDF contains one or two Public Key file Attachments:

1. The OpenPGP Public Key file ``creator.asc`` of the |PRODUCT_NAME|
   server.

  .. RST_HTML_NEWLINE

2. If the User who created the PDF has a
   :ref:`registered <ch-webapp-admin-user-edit-openpgp>` OpenPGP Public
   Key ID, the public key file ``author.asc`` as retrieved from the
   configured :ref:`Public Key Server <ch-install-on-linux-config-user-home-clean>`
   (and persisted in the user's SafePages home).