docums-encryptcontent-plugin 2.0.1

A Docums plugin that encrypt/decrypt markdown content with AES

docums-encryptcontent-plugin

This plugin allows you to have password protected articles and pages in Docums.

The content is encrypted with AES-256 in Python using PyCryptodome, and decrypted in the browser with Crypto-JS.

It has been tested in Python Python 3.5+

Usecase

I want to be able to protect the content of the page with a password.

Define a password to protect each page independently or a global password to protect them all.

If a global password exists, all articles and pages are protected with this password.

If a password is defined in an article or a page, it is always used even if there is a global password.

If a password is defined as an empty character string, the content is not protected.

Table of Contents

• Installation
• Usage
  • Global password protection
  • Customization
• Features
  • HighlightJS support (default)
  • Arithmatex support (default)
  • Tag encrypted page (default)
  • Rebember password
  • Encrypt something
  • Search index encryption
  • Add button
  • Reload scripts
• Contributing

Installation

Install the package with pip:

pip install docums-encryptcontent-plugin

Install the package from source with pip:

cd docums-encryptcontent-plugin/
python3 setup.py sdist bdist_wheel
pip3 install dist/docums_encryptcontent_plugin-2.0.1-py3-none-any.whl

Enable the plugin in your docums.yml:

plugins:
    - search: {}
    - encryptcontent: {}

NOTE: If you have no plugins entry in your configuration file yet, you'll likely also want to add the search plugin. Docums enables it by default if there is no plugins entry set, but now you have to enable it explicitly.

Usage

Add an meta tag password: secret_password in your markdown files to protect them.

Global password protection

Add global_password: your_password in plugin configuration variable, to protect by default your articles with this password

plugins:
    - encryptcontent:
        global_password: 'your_password'

If a password is defined in an article, it will ALWAYS overwrite the global password.

NOTE Keep in mind that if the password: tag exists without value in an article, it will not be protected !

Extra vars customization

Optionally you can use some extra variables in plugin configuration to customize default messages.

plugins:
    - encryptcontent:
        title_prefix: '[LOCK]'
        summary: 'another informational message to encrypted content'
        placeholder: 'another password placeholder'
        decryption_failure_message: 'another informational message when decryption fail'
        encryption_info_message: 'another information message when you dont have acess !'

Default prefix title is [Protected].

Default summary message is This content is protected with AES encryption..

Default password palceholder is Provide password and press ENTER.

Default decryption failure message is Invalid password..

Defaut encryption information message is Contact your administrator for access to this page..

NOTE Adding a prefix to the title does not change the default navigation path !

Features

HighlightJS support

Enable by default

If HighlightJS module is detected in your theme to improve code color rendering, reload renderer after decryption process. If HighlightJS module is not correctly detected, you can force the detection by adding hljs: True on the plugin configuration or set hljs: False to disable this feature.

When enable the following part of the template is add to force reloading decrypted content.

{% if hljs %}
document.getElementById("docums-decrypted-content").querySelectorAll('pre code').forEach((block) => {
    hljs.highlightBlock(block);
});
{% endif %}

Arithmatex support

Enable by default

If Arithmatex markdown extension is detected in your markdown extensions to improve math equations rendering, reload renderer after decryption process. If the Arithmatex markdown extension is not correctly detected, you can force the detection by adding arithmatex: True on the plugin configuration or set arithmatex: False to disable this feature.

When enable, the following part of the template is add to force math equations rendering on decrypted content.

{% if arithmatex %}
MathJax.typesetPromise()
{% endif %}

NOTE It has been tested in Arithmatex generic mode only.

Tag encrypted page

Enable by default

This feature add an additional attribute encrypted with value True to the docums type docums.nav.page object.

You can add tag_encrypted_page: False in plugin configuration, to disable tagging of encrypted pages. BUT This feature is neccessary for others feature working correctly. If you disable this feature, do no use Encrypt Somethings,

When enable, it becomes possible to use encrypted attribute in the jinja template of your theme, as a condition to perform custom modification.

{%- for nav_item in nav %}
    {% if nav_item.encrypted %}
        <!-- Do something --> 
    {% endif %}
{%- endfor %}

For example, in your theme template, you can use conditional check to add custom class :

<a {% if nav_item.encrypted %}class="docums-encrypted-class"{% endif %}href="{{ nav_item.url|url }}">{{ nav_item.title }}</a>

Add button

Add password_button: True in plugin config variable, to add button to the right of the password field decrypt the content.

Optionnally, you can add password_button_text: 'custome_text_button' to customize the button text.

plugins:
    - encryptcontent:
        password_button: True
        password_button_text: 'custome_text_button'

Rebember password

:warning: This feature is not really secure ! Password are store in clear text inside local storage.

Instead of using this feature, I recommend to use a password manager with its web plugins. For example KeepassXC allows you, with a simple keyboard shortcut, to detect the password field docums-content-password and to fill it automatically in a much more secure way.

If you do not have password manager, you can set remember_password: True in your docums.yml to enable password remember feature.

When enabled, each time you fill password form and press Enter a key on local storage is create with your password as value. When you reload the page, if you already have an 'encryptcontent' key in the local storage of your browser, the page will be automatically decrypted using the value previously created.

By default, the key is created with a name relative to the page on which it was generated. This 'relative' key will always be used as first attempt to decrypt the current page when loading.

If your password is a global password, you can fill in the form field docums-content-password, then use the keyboard shortcut CTRL + ENTER instead of the classic ENTER. The key that will be created with a generic name to making it accessible, by default, on all the pages of your site.

The form of decryption remains visible as long as the content has not been successfully decrypted, which allows in case of error to retry. All keys created with this feature on localstorage have an default expire time daly set to 24 hours, just cause ...

However (optionally), its possible to change the default expire time by setting options default_expire_dalay: <number> in your docums.yml. Your configuration should look like this when you enabled this feature :

plugins:
    - encryptcontent:
        remember_password: True
        default_expire_dalay: 24   # <-- Default expire delay in hours (optional)

NOTE The expired elements of the localStorage are only deleted by the execution of the decrypt-content.js scripts and therefore by the navigation on the site. Secret items can therefore remain visible in local storage after their expiration dates.

Encrypt something

The tag encrypted page feature MUST be enabled (it's default) for this feature to work properly.

Add encrypted_something: {} in the plugin configuration variable, to encrypt something else.

The syntax of this new variable MUST follow the yaml format of a dictionary. Child elements of encrypted_something are build with a key <unique name> in string format and a list as value. The list have to be contructed with the name of an HTML element <html tag> as first item and id or class as the second item.

plugins:
    - encryptcontent:
        encrypted_something:
            <uniq name>: [<html tag>, <'class' or 'id'>]

The <unique name> key identifies the name of a specific element of the page that will be searched by beautifulSoup. The first value of the <html tag> list identifies the type of HTML tag in which the name is present. The second value of the list, as string 'id' or 'class', specifies the type of the attribute which contains the unique name in the html tag.

Prefer to use an 'id', however depending on the template of your theme, it is not always possible to use the id. So we can use the class attribute to define your unique name inside html tag. BeautifulSoup will encrypt all HTML elements discovered with the class.

When the feature is enabled, you can use any methods (password, button, remember) to decrypt every elements encrypted on the page.

By default every child items are encrypted and the encrypted elements have style=display:none to hide their content.

How to use it :exploding_head: ?! Examples

Use the page.encrypted conditions to add attributes of type id or class in the HTML templates of your theme. Each attribute is identified with a unique name and is contained in an html element. Then add these elements in the format of a yaml dictionary under the variable encrypted_something.

1. For example, encrypt ToC in a theme where ToC is under 'div' element like this :

<div class=".." {% if page.encrypted %}id="docums-encrypted-toc"{% endif %}>
    <ul class="..">
        <li class=".."><a href="{{ toc_item.url }}">{{ toc_item.title }}</a></li>
         <li><a href="{{ toc_item.url }}">{{ toc_item.title }}</a></li>
    </ul>
</div>

Set your configuration like this :

plugins:
    - encryptcontent:
        encrypted_something:
            docums-encrypted-toc: [div, id]

2. Other example, with multiples target. In you Material Theme, you want to encrypt ToC content and Footer.

Materiel generate 2 <nav> structure with the same template toc.html, so you need to use a class instead of an id for this part. The footer part, is generated by the footer.html template in a classic div so an id is sufficient

After modification, your template looks like this :

<nav class="md-nav md-nav--secondary {% if page.encrypted %}docums-encrypted-toc{% endif %}" aria-label="{{ lang.t('toc.title') }}">
    <label class="md-nav__title" for="__toc"> ... </label>
    <ul class="md-nav__list" data-md-scrollfix> ... </ul>
</nav>

<footer class="md-footer">
    <div class="md-footer-nav" {% if page.encrypted %}id="docums-encrypted-footer"{% endif %}> ... </div>
    <div class="md-footer-meta md-typeset" {% if page.encrypted %}id="docums-encrypted-footer-meta"{% endif %}>
</footer>

Your configuration like this :

plugins:
    - encryptcontent:
        encrypted_something:
            docums-encrypted-toc: [nav, class]
            docums-encrypted-footer: [div, id]
            docums-encrypted-footer-meta: [div, id]

Search index encryption

Default value is "encrypted"

:warning: The configuration mode "clear" of this functionality can cause DATA LEAK

The unencrypted content of each page is accessible through the search index. Not encrypting the search index means completely removing the protection provided by this plugin. You have been warned

This feature allows you to control the behavior of the encryption plugin with the search index. Three configuration modes are possible:

• clear : Search index is not encrypted. Search is possible even on protected pages.
• dynamically : Search index is encrypted on build. Search is possible once the pages have been decrypted ones.
• encrypted : Search index is encrypted on build. Search is not possible on all encrypted pages.

You can set search_index: '<mode_name>' in your docums.yml to change the search index encryption mode. Possible values are clear, dynamically, encrypted. The default mode is "encrypted".

plugins:
    - encryptcontent:
        search_index: 'dynamically'

This functionality overwrite the index creation function of the “search” plug-in provided by docums. The modifications carried out make it possible to encrypt the content of the search index after the default plugin has carried out these treatments (search configuration). It is therefore dependent on the default search plugin.

When the configuration mode is set to "dynamically", the javascripts contribution files are used to override the default search plugin files provided by Docums. They include a process of decrypting and keeping the search index in a SessionStorage.

NOTE The mode 'dynamically' is currently not compatible with Material Theme !

Add button

Add password_button: True in plugin configuration variable, to add button to the right of the password field.

When enable, it allows to decrypt the content just like the classic keypress ENTER. If remember password feature is activated, use button to decrypt generate a 'relative' key on your local storage. You cannot use password button to create global password value.

Optionnally, you can add password_button_text: 'custom_text_button' to customize the button text.

plugins:
    - encryptcontent:
        password_button: True
        password_button_text: 'custom_text_button'

Reload scripts

You can set reload_scripts: in your docums.yml with list of script source, to reload and execute some js lib after decryption process.

plugins:
    reload_scripts:
        - "./js/example.js"

This feature use the following JQuery function to remove, add and reload javascripts.

var reload_js = function(src) {
    $('script[src="' + src + '"]').remove();
    $('<script>').attr('src', src).appendTo('head');
};