https://github.com/rnag/cert-hero
Python Stand-alone Library to Download the SSL Certificate for Any Host™
https://github.com/rnag/cert-hero
asn asn1crypto cert certificate python python-ssl python3 ssl ssl-cert ssl-certificates
Last synced: about 2 months ago
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Python Stand-alone Library to Download the SSL Certificate for Any Host™
- Host: GitHub
- URL: https://github.com/rnag/cert-hero
- Owner: rnag
- License: mit
- Created: 2023-10-16T19:02:05.000Z (over 1 year ago)
- Default Branch: main
- Last Pushed: 2023-11-06T20:11:37.000Z (over 1 year ago)
- Last Synced: 2025-04-13T16:05:29.084Z (about 2 months ago)
- Topics: asn, asn1crypto, cert, certificate, python, python-ssl, python3, ssl, ssl-cert, ssl-certificates
- Language: Python
- Homepage: https://cert-hero.readthedocs.io
- Size: 208 KB
- Stars: 7
- Watchers: 5
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.rst
- Changelog: HISTORY.rst
- Contributing: CONTRIBUTING.rst
- License: LICENSE
Awesome Lists containing this project
README
=========
Cert Hero
=========
.. image:: https://img.shields.io/pypi/v/cert-hero.svg
:target: https://pypi.org/project/cert-hero
.. image:: https://img.shields.io/pypi/pyversions/cert-hero.svg
:target: https://pypi.org/project/cert-hero
.. image:: https://github.com/rnag/cert-hero/actions/workflows/dev.yml/badge.svg
:target: https://github.com/rnag/cert-hero/actions/workflows/dev.yml
.. image:: https://readthedocs.org/projects/cert-hero/badge/?version=latest
:target: https://cert-hero.readthedocs.io/en/latest/?version=latest
:alt: Documentation Status
.. image:: https://pyup.io/repos/github/rnag/cert-hero/shield.svg
:target: https://pyup.io/repos/github/rnag/cert-hero/
:alt: Updates
Python Stand-alone Library to Download the SSL Certificate for *Any Host™*
* Documentation: https://cert-hero.readthedocs.io.
-------------------
**Why Use?**
* This library *always* returns the SSL certificate, if a server has one. This works for expired
and `self-signed certificate`_, whereas the builtin ``ssl`` library returns an empty ``dict`` if verification fails
for any reason (source_).
* The *only* dependency is `asn1crypto`_ (with over 300 stars on GitHub), which is ~94% more lightweight and robust
than a solution with `pyOpenSSL`_ (chart_).
* If a host *redirects* to another URL, this info is captured in ``Location`` and ``Status``.
* Convenience methods such as ``__repr__()`` to make output more human-readable.
**Core Exports**
* `cert_please`_ - Retrieve the SSL certificate for a given hostname.
* `certs_please`_ - Retrieve (concurrently) the SSL certificate(s) for a list of hostnames.
* `set_expired`_ - Helper function to check (at runtime) if a cert is expired or not.
.. _chart: https://raw.githubusercontent.com/rnag/cert-hero/main/images/SizeComparison.png
.. _ssl: https://docs.python.org/3/library/ssl.html
.. _asn1crypto: https://pypi.org/project/asn1crypto
.. _pyOpenSSL: https://pypi.org/project/pyOpenSSL/
.. _source: https://stackoverflow.com/a/74349032/10237506
.. _self-signed certificate: https://stackoverflow.com/a/68889470/10237506
.. _`cert_please`: https://cert-hero.readthedocs.io/en/latest/cert_hero.html#cert_hero.cert_please
.. _`certs_please`: https://cert-hero.readthedocs.io/en/latest/cert_hero.html#cert_hero.certs_please
.. _`set_expired`: https://cert-hero.readthedocs.io/en/latest/cert_hero.html#cert_hero.set_expired
Install
-------
.. code-block:: console
$ pip install cert-hero
Usage
-----
Fetch the SSL certificate for a **host** with ``cert_please()``:
.. code:: python3
import cert_hero
cert = cert_hero.cert_please('google.com')
print('Cert is Valid Till:', cert.not_after_date.isoformat())
# To get the output as a JSON string, use `str(cert)` or remove `!r` from below
print(f'Cert -> \n{cert!r}')
cert_hero.set_expired(cert)
print(f'Validity ->\n{cert["Validity"]}')
*Output (Sample)*
.. code::
Cert is Valid Till: 2023-10-28
Cert ->
CertHero(
{
"Cert Status": "SUCCESS",
"Serial": "753DD6FF20CB1B4510CB4C1EA27DA2EB",
"Subject Name": {
"Common Name": "*.google.com"
},
"Issuer Name": {
"Country": "US",
"State/Province": "California",
"Organization": "Zscaler Inc.",
"Organization Unit": "Zscaler Inc.",
"Common Name": "Zscaler Intermediate Root CA (zscalerthree.net) (t) "
},
"Validity": {
"Not After": "2023-10-28",
"Not Before": "2023-10-14"
},
"Wildcard": true,
"Signature Algorithm": "SHA256WITHRSA",
"Key Algorithm": "RSA-2048",
"Subject Alt Names": [
"*.google.com",
"*.appengine.google.com",
"youtu.be",
"*.youtube.com",
...
],
"Location": "https://www.google.com/",
"Status": 301
}
)
Validity ->
{'Not After': '2023-10-28', 'Not Before': '2023-10-14', 'Expired': False}
Fetch (concurrently) the SSL certificates for **multiple hosts** with ``certs_please()``:
.. code:: python3
import cert_hero
host_to_cert = cert_hero.certs_please(['google.com', 'cnn.com', 'www.yahoo.co.in', 'youtu.be'])
cert_hero.set_expired(host_to_cert)
for host, cert in host_to_cert.items():
print(f'=== {host.center(17)} ===')
# To get the output as a JSON string, use `str(cert)` or remove `!r` from below
print(f'{cert!r}')
print()
*Output (Sample)*
.. code::
=== google.com ===
CertHero(
{
"Cert Status": "SUCCESS",
"Serial": "753DD6FF20CB1B4510CB4C1EA27DA2EB",
"Subject Name": {
"Common Name": "*.google.com"
},
...
}
)
=== cnn.com ===
CertHero(
{
"Cert Status": "SUCCESS",
"Serial": "7F2F3E5C350554D71A6784CCFE6E8315",
"Subject Name": {
"Common Name": "cnn.com"
},
...
}
)
=== www.yahoo.co.in ===
CertHero(
{
"Cert Status": "SUCCESS",
"Serial": "7D7FD7B7C2EE7146B4D4E43E36908B72",
"Subject Name": {
"Common Name": "src1.yahoo.com"
},
...
}
)
=== youtu.be ===
CertHero(
{
"Cert Status": "SUCCESS",
"Serial": "753DD6FF20CB1B4510CB4C1EA27DA2EB",
"Subject Name": {
"Common Name": "*.google.com"
},
...
}
)
Usage as a CLI
--------------
After the installation step you can use cert-hero just typing ``ch`` in your terminal window.
The ``ch`` command allows you to retrieve the SSL certificate(s) for one or more given host.
For example::
ch google.com cnn.com
You can get help about the main command using::
ch --help
Rationale
---------
The builtin Python module ``ssl`` can be used to retrieve a certificate from a server via ``getpeercert``,
but it'll work only if the certificate of interest can be successfully verified (source_).
If, for any reason, verification fails, like, for example, with expired or a `self-signed certificate`_,
we'll get ``ssl.SSLCertVerificationError`` instead of the requested info.
We can work around this by asking for the certificate in the binary form:
.. code-block:: python3
getpeercert(binary_form=True)
But now we have to convert it, and thus we can use a third party ``asn1crypto`` module, instead of
the (bulkier) ``cryptography`` module.
Credits
-------
This package was created with Cookiecutter_ and the `rnag/cookiecutter-pypackage`_ project template.
.. _Cookiecutter: https://github.com/cookiecutter/cookiecutter
.. _`rnag/cookiecutter-pypackage`: https://github.com/rnag/cookiecutter-pypackage