Django Content Security Policy Reports

A Django app for handling reports from web browsers of violations of your website's content security policy.

This app does not handle the setting of the Content-Security-Policy HTTP headers, but deals with handling the reports that web browsers may submit to your site (via the report-uri) when the stated content security policy is violated.

It is recommended that you use an app such as django-csp (Github) to set the Content-Security-Policy headers.

So What Does This Thing Do?

It receives the reports from the browser and does any/all of the following with them:

Logs them using the python logging module.
Sends them to you via email.
Saves them to the database via a Django model.
Runs any of your own custom functions on them.
Can generate a summary of a reports.

Supported Django Versions

Supports Python 2.7, 3.5 to 3.8 and Django 1.11 to 3.0.

How Do I Use This Thing?

Install this app into your Django project, e.g. pip install django-csp-reports.
Add 'cspreports' to your INSTALLED_APPS.
Include cspreports.urls in your URL config somewhere, e.g. urlpatterns = [path('csp/', include('cspreports.urls'))].
In your Content-Security-Policy HTTP headers, set reverse('report_csp') as the report-uri. (Note, with django-csp, you will want to set CSP_REPORT_URI = reverse_lazy('report_csp') in settings.py).
Set all/any of the following in settings.py as you so desire, hopefully they are self-explanatory:
- CSP_REPORTS_EMAIL_ADMINS (bool defaults to True).
- CSP_REPORTS_LOG (bool, whether or not to log the reporting using the python logging module, defaults to True).
- CSP_REPORTS_LOG_LEVEL (str, one of the Python logging module's available log functions, defaults to 'warning').
- CSP_REPORTS_SAVE (bool defaults to True). Determines whether the reports are saved to the database.
- CSP_REPORTS_ADDITIONAL_HANDLERS (iterable defaults to []). Each value should be a dot-separated string path to a function which you want be called when a report is received. Each function is passed the HttpRequest of the CSP report.
- CSP_REPORTS_FILTER_FUNCTION (str of dotted path to a callable, defaults to None). If set, the specificed function is passed each HttpRequest object of the CSP report before it's processed. Only requests for which the function returns True are processed. See Filtering Requests below.
- CSP_REPORTS_LOGGER_NAME (str defaults to CSP Reports). Specifies the logger name that will be used for logging CSP reports, if enabled.
Set a cron to generate summaries.
Enjoy.

Commands

`clean_cspreports`

Deletes old reports from the database.

Options:

--limit - timestamp that all reports created since will not be deleted. Defaults to 1 week. Accepts any string that can be parsed as a datetime.

`make_csp_summary`

Generates a summary of CSP reports.

By default includes reports from yesterday (00:00:00 to midnight). The summary shows the top 10 violation sources (i.e. pages from which violations were reported), the top 10 blocked URIs (banned resources which the pages tried to load), and the top 10 invalid reports (which the browser provided an invalid CSP report).

Options:

--since - timestamp of the oldest reports to include. Accepts any string that can be parsed as a datetime.
--to - timestamp of the newest reports to include. Accepts any string that can be parsed as a datetime.
--top - limit of how many examples to show. Default is 10.

Filtering Requests

If you want to filter out some CSP reports (e.g. reports caused by browser extensions trying to inject scripts into the page), you can do so using the CSP_REPORTS_FILTER_FUNCTION.

Example

# settings.py
CSP_REPORTS_FILTER_FUNCTION = 'myapp.utils.filter_csp_report'

# myapp/utils.py
import json

def filter_csp_report(request):
    report = json_str = request.body
    if isinstance(json_str, bytes):
        json_str = json_str.decode(request.encoding or 'utf-8')
    report = json.loads(request.body)
    src_file = report.get('csp-report', {}).get('source-file', '')
    if src_file.startswith('moz-extension://'):
        return False
    return True