OneLogin’s SAML Python Toolkit

Add SAML support to your Python softwares using this library. Forget those complicated libraries and use that open source library provided and supported by OneLogin Inc.

Why add SAML support to my software?

SAML is an XML-based standard for web browser single sign-on and is defined by the OASIS Security Services Technical Committee. The standard has been around since 2002, but lately it is becoming popular due its advantages:

  • Usability - One-click access from portals or intranets, deep linking, password elimination and automatically renewing sessions make life easier for the user.
  • Security - Based on strong digital signatures for authentication and integrity, SAML is a secure single sign-on protocol that the largest and most security conscious enterprises in the world rely on.
  • Speed - SAML is fast. One browser redirect is all it takes to securely sign a user into an application.
  • Phishing Prevention - If you don’t have a password for an app, you can’t be tricked into entering it on a fake login page.
  • IT Friendly - SAML simplifies life for IT because it centralizes authentication, provides greater visibility and makes directory integration easier.
  • Opportunity - B2B cloud vendor should support SAML to facilitate the integration of their product.

General description

OneLogin’s SAML Python toolkit let you build a SP (Service Provider) over your Python application and connect it to any IdP (Identity Provider).

Supports:

  • SSO and SLO (SP-Initiated and IdP-Initiated).
  • Assertion and nameId encryption.
  • Assertion signature.
  • Message signature: AuthNRequest, LogoutRequest, LogoutResponses.
  • Enable an Assertion Consumer Service endpoint.
  • Enable a Single Logout Service endpoint.
  • Publish the SP metadata (which can be signed).

Key features:

  • saml2int - Implements the SAML 2.0 Web Browser SSO Profile.
  • Session-less - Forget those common conflicts between the SP and the final app, the toolkit delegate session in the final app.
  • Easy to use - Programmer will be allowed to code high-level and low-level programming, 2 easy to use APIs are available.
  • Tested - Thoroughly tested.
  • Popular - OneLogin’s customers use it. Add easy support to your django/flask web projects.

Installation

Dependences

  • python 2.7
  • M2Crypto A Python crypto and SSL toolkit (depends on swig)
  • dm.xmlsec.binding Cython/lxml based binding for the XML security library (depends on python-dev libxml2-dev libxmlsec1-dev)
  • isodate An ISO 8601 date/time/duration parser and formater
  • defusedxml XML bomb protection for Python stdlib modules

Review the setup.py file to know the version of the library that python-saml is using

Code

Option 1. Download from github

The toolkit is hosted on github. You can download it from:

Copy the core of the library (src/onelogin/saml2 folder) and merge the setup.py inside the python application. (each application has its structure so take your time to locate the Python SAML toolkit in the best place).

Option 2. Download from pypi

The toolkit is hosted in pypi, you can find the python-saml package at https://pypi.python.org/pypi/python-saml

You can install it executing:

pip install python-saml

If you want to know how a project can handle python packages review this guide and review this sampleproject

Getting started

Knowing the toolkit

The new OneLogin SAML Toolkit contains different folders (certs, lib, demo-django, demo-flask and tests) and some files.

Let’s start describing them:

src

This folder contains the heart of the toolkit, onelogin/saml2 folder contains the new version of the classes and methods that are described in a later section.

demo-django

This folder contains a Django project that will be used as demo to show how to add SAML support to the Django Framework. ‘demo’ is the main folder of the django project (with its settings.py, views.py, urls.py), ‘templates’ is the django templates of the project and ‘saml’ is a folder that contains the ‘certs’ folder that could be used to store the x509 public and private key, and the saml toolkit settings (settings.json and advanced_settings.json).

*Notice about certs*

SAML requires a x.509 cert to sign and encrypt elements like NameID, Message, Assertion, Metadata.

If our environment requires sign or encrypt support, the certs folder may contain the x509 cert and the private key that the SP will use:

  • sp.crt The public cert of the SP
  • sp.key The privake key of the SP

Or also we can provide those data in the setting file at the ‘x509cert’ and the privateKey’ json parameters of the ‘sp’ element.

Sometimes we could need a signature on the metadata published by the SP, in this case we could use the x.509 cert previously mentioned or use a new x.509 cert: metadata.crt and metadata.key.

If you want to create self-signed certs, you can do it at the https://www.samltool.com/self_signed_certs.php service, or using the command:

openssl req -new -x509 -days 3652 -nodes -out sp.crt -keyout saml.key

demo-flask

This folder contains a Flask project that will be used as demo to show how to add SAML support to the Flask Framework. ‘index.py’ is the main flask file that has all the code, this file uses the templates stored at the ‘templates’ folder. In the ‘saml’ folder we found the ‘certs’ folder to store the x509 public and private key, and the saml toolkit settings (settings.json and advanced_settings.json).

setup.py

Setup script is the centre of all activity in building, distributing, and installing modules. Read more at https://pythonhosted.org/an_example_pypi_project/setuptools.html

tests

Contains the unit test of the toolkit.

In order to execute the test you only need to load the virtualenv with the toolkit installed on it and execute:

python setup.py test

The previous line will run the tests for the whole toolkit. You can also run the tests for a specific module. To do so for the auth module you would have to execute this:

python setup.py test --test-suite tests.src.OneLogin.saml2_tests.auth_test.OneLogin_Saml2_Auth_Test

With the –test-suite parameter you can specify the module to test. You’ll find all the module available and their class names at tests/src/OneLogin

This is the settings.json file:

{
    // If strict is True, then the Python Toolkit will reject unsigned
    // or unencrypted messages if it expects them to be signed or encrypted.
    // Also it will reject the messages if the SAML standard is not strictly
    // followed. Destination, NameId, Conditions ... are validated too.
    "strict": true,

    // Enable debug mode (outputs errors).
    "debug": true,

    // Service Provider Data that we are deploying.
    "sp": {
        // Identifier of the SP entity  (must be a URI)
        "entityId": "https://<sp_domain>/metadata/",
        // Specifies info about where and how the <AuthnResponse> message MUST be
        // returned to the requester, in this case our SP.
        "assertionConsumerService": {
            // URL Location where the <Response> from the IdP will be returned
            "url": "https://<sp_domain>/?acs",
            // SAML protocol binding to be used when returning the <Response>
            // message. OneLogin Toolkit supports this endpoint for the
            // HTTP-POST binding only.
            "binding": "urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST"
        },
        // Specifies info about where and how the <Logout Response> message MUST be
        // returned to the requester, in this case our SP.
        "singleLogoutService": {
            // URL Location where the <Response> from the IdP will be returned
            "url": "https://<sp_domain>/?sls",
            // SAML protocol binding to be used when returning the <Response>
            // message. OneLogin Toolkit supports the HTTP-Redirect binding
            // only for this endpoint.
            "binding": "urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Redirect"
        },
        // Specifies the constraints on the name identifier to be used to
        // represent the requested subject.
        // Take a look on src/onelogin/saml2/constants.py to see the NameIdFormat that are supported.
        "NameIDFormat": "urn:oasis:names:tc:SAML:2.0:nameid-format:unspecified",
        // Usually x509cert and privateKey of the SP are provided by files placed at
        // the certs folder. But we can also provide them with the following parameters
        'x509cert' => '',
        'privateKey' > ''
    },

    // Identity Provider Data that we want connected with our SP.
    "idp": {
        // Identifier of the IdP entity  (must be a URI)
        "entityId": "https://app.onelogin.com/saml/metadata/<onelogin_connector_id>",
        // SSO endpoint info of the IdP. (Authentication Request protocol)
        "singleSignOnService": {
            // URL Target of the IdP where the Authentication Request Message
            // will be sent.
            "url": "https://app.onelogin.com/trust/saml2/http-post/sso/<onelogin_connector_id>",
            // SAML protocol binding to be used when returning the <Response>
            // message. OneLogin Toolkit supports the HTTP-Redirect binding
            // only for this endpoint.
            "binding": "urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Redirect"
        },
        // SLO endpoint info of the IdP.
        "singleLogoutService": {
            // URL Location of the IdP where SLO Request will be sent.
            "url": "https://app.onelogin.com/trust/saml2/http-redirect/slo/<onelogin_connector_id>",
            // SAML protocol binding to be used when returning the <Response>
            // message. OneLogin Toolkit supports the HTTP-Redirect binding
            // only for this endpoint.
            "binding": "urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Redirect"
        },
        // Public x509 certificate of the IdP
        "x509cert": "<onelogin_connector_cert>"
        /*
         *  Instead of use the whole x509cert you can use a fingerprint
         *  (openssl x509 -noout -fingerprint -in "idp.crt" to generate it)
         */
        // "certFingerprint": ""

    }
}

In addition to the required settings data (idp, sp), there is extra information that could be defined at advanced_settings.json

{
    // Security settings
    "security": {

        /** signatures and encryptions offered **/

        // Indicates that the nameID of the <samlp:logoutRequest> sent by this SP
        // will be encrypted.
        "nameIdEncrypted": false,

        // Indicates whether the <samlp:AuthnRequest> messages sent by this SP
        // will be signed.  [Metadata of the SP will offer this info]
        "authnRequestsSigned": false,

        // Indicates whether the <samlp:logoutRequest> messages sent by this SP
        // will be signed.
        "logoutRequestSigned": false,

        // Indicates whether the <samlp:logoutResponse> messages sent by this SP
        // will be signed.
        "logoutResponseSigned": false,

        /* Sign the Metadata
         false || true (use sp certs) || {
                                            "keyFileName": "metadata.key",
                                            "certFileName": "metadata.crt"
                                         }
        */
        "signMetadata": false,

        /** signatures and encryptions required **/

        // Indicates a requirement for the <samlp:Response>, <samlp:LogoutRequest>
        // and <samlp:LogoutResponse> elements received by this SP to be signed.
        "wantMessagesSigned": false,

        // Indicates a requirement for the <saml:Assertion> elements received by
        // this SP to be signed. [Metadata of the SP will offer this info]
        "wantAssertionsSigned": false,

        // Indicates a requirement for the NameID received by
        // this SP to be encrypted.
        "wantNameIdEncrypted": false
    },

    // Contact information template, it is recommended to suply a
    // technical and support contacts.
    "contactPerson": {
        "technical": {
            "givenName": "technical_name",
            "emailAddress": "technical@example.com"
        },
        "support": {
            "givenName": "support_name",
            "emailAddress": "support@example.com"
        }
    },

    // Organization information template, the info in en_US lang is
    // recomended, add more if required.
    "organization": {
        "en-US": {
            "name": "sp_test",
            "displayname": "SP test",
            "url": "http://sp.example.com"
        }
    }
}

In the security section, you can set the way that the SP will handle the messages and assertions. Contact the admin of the IdP and ask him what the IdP expects, and decide what validations will handle the SP and what requirements the SP will have and communicate them to the IdP’s admin too.

Once we know what kind of data could be configured, let’s talk about the way settings are handled within the toolkit.

The settings files described (settings.json and advanced_settings.json) are loaded by the toolkit if not other dict with settings info is provided in the constructors of the toolkit. Let’s see some examples.

# Initializes toolkit with settings.json & advanced_settings.json files.
auth = OneLogin_Saml2_Auth(req)
# or
settings = OneLogin_Saml2_Settings()

# Initializes toolkit with settings.json & advanced_settings.json files from a custom base path.
custom_folder = '/var/www/django-project'
auth = OneLogin_Saml2_Auth(req, custom_base_path=custom_folder)
# or
settings = OneLogin_Saml2_Settings(custom_base_path=custom_folder)

# Initializes toolkit with the dict provided.
auth = OneLogin_Saml2_Auth(req, settings_data)
# or
settings = OneLogin_Saml2_Settings(settings_data)

You can declare the settings_data in the file that constains the constructor execution or locate them in any file and load the file in order to get the dict available as we see in the following example:

filename = "/var/www/django-project/custom_settings.json" # The custom_settings.json contains a
json_data_file = open(filename, 'r')                      # settings_data dict.
settings_data = json.load(json_data_file)
json_data_file.close()

auth = OneLogin_Saml2_Auth(req, settings_data)

How load the library

In order to use the toolkit library you need to import the file that contains the class that you will need on the top of your python file.

from onelogin.saml2.auth import OneLogin_Saml2_Auth
from onelogin.saml2.settings import OneLogin_Saml2_Settings
from onelogin.saml2.utils import OneLogin_Saml2_Utils

The Request

Building an OneLogin_Saml2_Auth object requires a ‘request’ parameter.

auth = OneLogin_Saml2_Auth(req)

This parameter has the following scheme:

req = {
    "http_host": "",
    "script_name": "",
    "server_port": "",
    "get_data": "",
    "post_data": ""
}

Each python framework built its own request object, you may map its data to match what the saml toolkit expects. Let`s see some examples:

def prepare_from_django_request(request):
    return {
        'http_host': request.META['HTTP_HOST'],
        'script_name': request.META['PATH_INFO'],
        'server_port': request.META['SERVER_PORT'],
        'get_data': request.GET.copy(),
        'post_data': request.POST.copy()
    }

def prepare_from_flask_request(request):
    url_data = urlparse(request.url)
    return {
        'http_host': request.host,
        'server_port': url_data.port,
        'script_name': request.path,
        'get_data': request.args.copy(),
        'post_data': request.form.copy()
    }

Initiate SSO

In order to send an AuthNRequest to the IdP:

from onelogin.saml2.auth import OneLogin_Saml2_Auth

req = prepare_request_for_toolkit(request)
auth = OneLogin_Saml2_Auth(req)   # Constructor of the SP, loads settings.json
                                  # and advanced_settings.json

auth.login()      # Method that builds and sends the AuthNRequest

The AuthNRequest will be sent signed or unsigned based on the security info of the advanced_settings.json (‘authnRequestsSigned’).

The IdP will return the SAML Response to the Attribute Consumer Service of the SP.

We can set a ‘return_to’ url parameter to the login function and that will be converted as a ‘RelayState’ parameter:

target_url = 'https://example.com'
auth.login(return_to=target_url)

The SP Endpoints

Related to the SP there are 3 important endpoints: The metadata view, the ACS view and the SLS view. The toolkit provides examples of those views in the demos, but lets see an example.

*SP Metadata*

This code will provide the XML metadata file of our SP, based on the info that we provided in the settings files.

req = prepare_request_for_toolkit(request)
auth = OneLogin_Saml2_Auth(req)
saml_settings = auth.get_settings()
metadata = saml_settings.get_sp_metadata()
errors = saml_settings.validate_metadata(metadata)
if len(errors) == 0:
    print metadata
else:
    print "Error found on Metadata: %s" % (', '.join(errors))

The get_sp_metadata will return the metadata signed or not based on the security info of the advanced_settings.json (‘signMetadata’).

Before the XML metadata is exposed, a check takes place to ensure that the info to be provided is valid.

*Attribute Consumer Service(ACS)*

This code handles the SAML response that the IdP returns to the SP.

req = prepare_request_for_toolkit(request)
auth = OneLogin_Saml2_Auth(req)
auth.process_response()
errors = auth.get_errors()
if not errors:
    if not auth.is_authenticated():
        request.session['samlUserdata'] = auth.get_attributes()
        if 'RelayState' in req['post_data'] and
          OneLogin_Saml2_Utils.get_self_url(req) != req['post_data']['RelayState']:
            auth.redirect_to(req['post_data']['RelayState'])
        else:
            for attr_name in request.session['samlUserdata'].keys():
                print '%s ==> %s' % (attr_name, '|| '.join(request.session['samlUserdata'][attr_name]))
    else:
      print 'Not authenticated'
else:
    print "Error when processing SAML Response: %s" % (', '.join(errors))

The SAML response is processed and then checked that there are no errors. It also verifies that the user is authenticated and stored the userdata in session.

At that point there are 2 possible alternatives:

  • If no RelayState is provided, we could show the user data in this view or however we wanted.
  • If RelayState is provided, a rediretion take place.

Notice that we saved the user data in the session before the redirection to have the user data available at the RelayState view.

In order to retrieve attributes we use:

attributes = auth.get_attributes();

With this method we get a dict with all the user data provided by the IdP in the Assertion of the SAML Response.

If we execute print attributes we could get:

{
    "cn": ["Jhon"],
    "sn": ["Doe"],
    "mail": ["Doe"],
    "groups": ["users", "members"]
}

Each attribute name can be used as a key to obtain the value. Every attribute is a list of values. A single-valued attribute is a listy of a single element.

The following code is equivalent:

attributes = auth.get_attributes();
print attributes['cn']

print auth.get_attribute('cn')

Before trying to get an attribute, check that the user is authenticated. If the user isn’t authenticated, an empty dict will be returned. For example, if we call to get_attributes before a auth.process_response, the get_attributes() will return an empty dict.

*Single Logout Service (SLS)*

This code handles the Logout Request and the Logout Responses.

delete_session_callback = lambda: request.session.flush()
url = auth.process_slo(delete_session_cb=delete_session_callback)
errors = auth.get_errors()
if len(errors) == 0:
    if url is not None:
        return redirect(url)
    else:
        print "Sucessfully Logged out"
else:
    print "Error when processing SLO: %s" % (', '.join(errors))

If the SLS endpoints receives a Logout Response, the response is validated and the session could be closed, using the callback.

# Part of the process_slo method
logout_response = OneLogin_Saml2_Logout_Response(self.__settings, self.__request_data['get_data']['SAMLResponse'])
if not logout_response.is_valid(self.__request_data, request_id):
    self.__errors.append('invalid_logout_response')
elif logout_response.get_status() != OneLogin_Saml2_Constants.STATUS_SUCCESS:
    self.__errors.append('logout_not_success')
elif not keep_local_session:
    OneLogin_Saml2_Utils.delete_local_session(delete_session_cb)

If the SLS endpoints receives an Logout Request, the request is validated, the session is closed and a Logout Response is sent to the SLS endpoint of the idP.

# Part of the process_slo method
request = OneLogin_Saml2_Utils.decode_base64_and_inflate(self.__request_data['get_data']['SAMLRequest'])
if not OneLogin_Saml2_Logout_Request.is_valid(self.__settings, request, self.__request_data):
    self.__errors.append('invalid_logout_request')
else:
    if not keep_local_session:
        OneLogin_Saml2_Utils.delete_local_session(delete_session_cb)

    in_response_to = OneLogin_Saml2_Logout_Request.get_id(request)
    response_builder = OneLogin_Saml2_Logout_Response(self.__settings)
    response_builder.build(in_response_to)
    logout_response = response_builder.get_response()

    parameters = {'SAMLResponse': logout_response}
    if 'RelayState' in self.__request_data['get_data']:
        parameters['RelayState'] = self.__request_data['get_data']['RelayState']

    security = self.__settings.get_security_data()
    if 'logoutResponseSigned' in security and security['logoutResponseSigned']:
        parameters['SigAlg'] = OneLogin_Saml2_Constants.RSA_SHA1
        parameters['Signature'] = self.build_response_signature(logout_response, parameters.get('RelayState', None))

    return self.redirect_to(self.get_slo_url(), parameters)

If we don’t want that process_slo to destroy the session, pass a true parameter to the process_slo method

keepLocalSession = true
auth.process_slo(keep_local_session=keepLocalSession);

Initiate SLO

In order to send a Logout Request to the IdP:

The Logout Request will be sent signed or unsigned based on the security info of the advanced_settings.json (‘logoutRequestSigned’).

The IdP will return the Logout Response to the Single Logout Service of the SP.

We can set a ‘return_to’ url parameter to the logout function and that will be converted as a ‘RelayState’ parameter:

target_url = 'https://example.com'
auth.logout(return_to=target_url)

Example of a view that initiates the SSO request and handles the response (is the acs target)

We can code a unique file that initiates the SSO process, handle the response, get the attributes, initiate the slo and processes the logout response.

Note: Review the demos, in a later section we explain the demo use case further in detail.

req = prepare_request_for_toolkit(request)  # Process the request and build the request dict that
                                            # the toolkit expects

auth = OneLogin_Saml2_Auth(req)             # Initialize the SP SAML instance

if 'sso' in request.args:                   # SSO action (SP-SSO initited).  Will send an AuthNRequest to the IdP
    return redirect(auth.login())
elif 'sso2' in request.args:                       # Another SSO init action
    return_to = '%sattrs/' % request.host_url      # but set a custom RelayState URL
    return redirect(auth.login(return_to))
elif 'slo' in request.args:                     # SLO action. Will sent a Logout Request to IdP
    return redirect(auth.logout())
elif 'acs' in request.args:                 # Assertion Consumer Service
    auth.process_response()                     # Process the Response of the IdP
    errors = auth.get_errors()              # This method receives an array with the errors
    if len(errors) == 0:                    # that could took place during the process
        if not auth.is_authenticated():         # This check if the response was ok and the user
            msg = "Not authenticated"           # data retrieved or not (user authenticated)
        else:
            request.session['samlUserdata'] = auth.get_attributes()     # Retrieves user data
            self_url = OneLogin_Saml2_Utils.get_self_url(req)
            if 'RelayState' in request.form and self_url != request.form['RelayState']:
                return redirect(auth.redirect_to(request.form['RelayState']))   # Redirect if there is a relayState
            else:                           # If there is user data we save that to print it later.
                msg = ''
                for attr_name in request.session['samlUserdata'].keys():
                    msg += '%s ==> %s' % (attr_name, '|| '.join(request.session['samlUserdata'][attr_name]))
elif 'sls' in request.args:                                             # Single Logout Service
    delete_session_callback = lambda: session.clear()           # Obtain session clear callback
    url = auth.process_slo(delete_session_cb=delete_session_callback)   # Process the Logout Request & Logout Response
    errors = auth.get_errors()              #  Retrieves possible validation errors
    if len(errors) == 0:
        if url is not None:
            return redirect(url)
        else:
            msg = "Sucessfully logged out"

if len(errors) == 0:
  print msg
else:
  print ', '.join(errors)

Main classes and methods

Described below are the main classes and methods that can be invoked from the SAML2 library.

OneLogin_Saml2_Auth - auth.py

Main class of OneLogin Python Toolkit

  • __init__ Initializes the SP SAML instance.
  • *login* Initiates the SSO process.
  • *logout* Initiates the SLO process.
  • *process_response* Process the SAML Response sent by the IdP.
  • *process_slo* Process the SAML Logout Response / Logout Request sent by the IdP.
  • *redirect_to* Redirects the user to the url past by parameter or to the url that we defined in our SSO Request.
  • *is_authenticated* Checks if the user is authenticated or not.
  • *get_attributes* Returns the set of SAML attributes.
  • *get_attribute* Returns the requested SAML attribute.
  • *get_nameid* Returns the nameID.
  • *get_session_index* Gets the SessionIndex from the AuthnStatement.
  • *get_errors* Returns a list with code errors if something went wrong.
  • *get_sso_url* Gets the SSO url.
  • *get_slo_url* Gets the SLO url.
  • *build_request_signature* Builds the Signature of the SAML Request.
  • *build_response_signature* Builds the Signature of the SAML Response.
  • *get_settings* Returns the settings info.
  • *set_strict* Set the strict mode active/disable.

OneLogin_Saml2_Auth - authn_request.py

SAML 2 Authentication Request class

  • __init__ This class handles an AuthNRequest. It builds an AuthNRequest object.
  • *get_request* Returns unsigned AuthnRequest.
  • *get_id* Returns the AuthNRequest ID.

OneLogin_Saml2_Response - response.py

SAML 2 Authentication Response class

  • __init__ Constructs the SAML Response object.
  • *is_valid* Determines if the SAML Response is valid. Includes checking of the signature by a certificate.
  • *check_status* Check if the status of the response is success or not
  • *get_audiences* Gets the audiences
  • *get_issuers* Gets the issuers (from message and from assertion)
  • *get_nameid_data* Gets the NameID Data provided by the SAML Response from the IdP (returns a dict)
  • *get_nameid* Gets the NameID provided by the SAML Response from the IdP (returns a string)
  • *get_session_not_on_or_after* Gets the SessionNotOnOrAfter from the AuthnStatement
  • *get_session_index* Gets the SessionIndex from the AuthnStatement
  • *get_attributes* Gets the Attributes from the AttributeStatement element.
  • *validate_num_assertions* Verifies that the document only contains a single Assertion (encrypted or not)
  • *validate_timestamps* Verifies that the document is valid according to Conditions Element
  • *get_error* After execute a validation process, if fails this method returns the cause

OneLogin_Saml2_LogoutRequest

SAML 2 Logout Request class

  • __init__ Constructs the Logout Request object.
  • *get_request* Returns the Logout Request defated, base64encoded.
  • *get_id* Returns the ID of the Logout Request.
  • *get_nameid_data* Gets the NameID Data of the the Logout Request (returns a dict).
  • *get_nameid* Gets the NameID of the Logout Request Message (returns a string).
  • *get_issuer* Gets the Issuer of the Logout Request Message.
  • *get_session_indexes* Gets the SessionIndexes from the Logout Request.
  • *is_valid* Checks if the Logout Request recieved is valid.
  • *get_error* After execute a validation process, if fails this method returns the cause.

OneLogin_Saml2_LogoutResponse

SAML 2 Logout Response class

  • __init__ Constructs a Logout Response object.
  • *get_issuer* Gets the Issuer of the Logout Response Message
  • *get_status* Gets the Status of the Logout Response.
  • *is_valid* Determines if the SAML LogoutResponse is valid
  • *build* Creates a Logout Response object.
  • *get_response* Returns a Logout Response object.
  • *get_error* After execute a validation process, if fails this method returns the cause.

OneLogin_Saml2_Settings

Configuration of the OneLogin Python Toolkit

  • __init__ Initializes the settings: Sets the paths of the different folders and Loads settings info from settings file or array/object provided.
  • *check_settings* Checks the settings info.
  • *get_errors* Returns an array with the errors, the array is empty when the settings is ok.
  • *get_sp_metadata* Gets the SP metadata. The XML representation.
  • *validate_metadata* Validates an XML SP Metadata.
  • *get_base_path* Returns base path.
  • *get_cert_path* Returns cert path.
  • *get_lib_path* Returns lib path.
  • *get_ext_lib_path* Returns external lib path.
  • *get_schemas_path* Returns schema path.
  • *check_sp_certs* Checks if the x509 certs of the SP exists and are valid.
  • *get_sp_key* Returns the x509 private key of the SP.
  • *get_sp_cert* Returns the x509 public cert of the SP.
  • *get_idp_cert* Returns the x509 public cert of the IdP.
  • *get_sp_data* Gets the SP data.
  • *get_idp_data* Gets the IdP data.
  • *get_security_data* Gets security data.
  • *get_contacts* Gets contacts data.
  • *get_organization* Gets organization data.
  • *format_idp_cert* Formats the IdP cert.
  • *format_sp_cert* Formats the SP cert.
  • *format_sp_key* Formats the private key.
  • *set_strict* Activates or deactivates the strict mode.
  • *is_strict* Returns if the ‘strict’ mode is active.
  • *is_debug_active* Returns if the debug is active.

OneLogin_Saml2_Metadata

A class that contains functionality related to the metadata of the SP

  • *builder* Generates the metadata of the SP based on the settings.
  • *sign_metadata* Signs the metadata with the key/cert provided.
  • *add_x509_key_descriptors* Adds the x509 descriptors (sign/encriptation) to the metadata

OneLogin_Saml2_Utils

Auxiliary class that contains several methods

  • *decode_base64_and_inflate* Base64 decodes and then inflates according to RFC1951.
  • *deflate_and_base64_encode* Deflates and the base64 encodes a string.
  • *validate_xml* Validates a xml against a schema.
  • *format_cert* Returns a x509 cert (adding header & footer if required).
  • *format_private_key* Returns a private key (adding header & footer if required).
  • *redirect* Executes a redirection to the provided url (or return the target url).
  • *get_self_url_host* Returns the protocol + the current host + the port (if different than common ports).
  • *get_self_host* Returns the current host.
  • *is_https* Checks if https or http.
  • *get_self_url_no_query* Returns the URL of the current host + current view.
  • *get_self_routed_url_no_query* Returns the routed URL of the current host + current view.
  • *get_self_url* Returns the URL of the current host + current view + query.
  • *generate_unique_id* Generates an unique string (used for example as ID for assertions).
  • *parse_time_to_SAML* Converts a UNIX timestamp to SAML2 timestamp on the form yyyy-mm-ddThh:mm:ss(.s+)?Z.
  • *parse_SAML_to_time* Converts a SAML2 timestamp on the form yyyy-mm-ddThh:mm:ss(.s+)?Z to a UNIX timestamp.
  • *now* Returns unix timestamp of actual time.
  • *parse_duration* Interprets a ISO8601 duration value relative to a given timestamp.
  • *get_expire_time* Compares 2 dates and returns the earliest.
  • *query* Extracts nodes that match the query from the Element.
  • *delete_local_session* Deletes the local session.
  • *calculate_x509_fingerprint* Calculates the fingerprint of a x509cert.
  • *format_finger_print* Formates a fingerprint.
  • *generate_name_id* Generates a nameID.
  • *get_status* Gets Status from a Response.
  • *decrypt_element* Decrypts an encrypted element.
  • *write_temp_file* Writes some content into a temporary file and returns it.
  • *add_sign* Adds signature key and senders certificate to an element (Message or Assertion).
  • *validate_sign* Validates a signature (Message or Assertion).
  • *validate_binary_sign* Validates signed bynary data (Used to validate GET Signature).

For more info, look at the source code; each method is documented and details about what does and how to use it are provided. Make sure to also check the doc folder where HTML documentation about the classes and methods is provided.

Demos included in the toolkit

The toolkit includes 2 demos to teach how use the toolkit (A django and a flask project), take a look on it. Demos require that SP and IdP are well configured before test it, so edit the settings files.

Notice that each python framework has it own way to handle routes/urls and process request, so focus on how it deployed. New demos using other python frameworks are welcome as a contribution.

Getting Started

We said that this toolkit includes a django application demo and a flask applicacion demo, lets see how fast is deploy them.

*Virtualenv*

The use of a virtualenv is highly recommended.

Virtualenv helps isolating the python enviroment used to run the toolkit. You can find more details and an installation guide in the official documentation.

Once you have your virtualenv ready and loaded, then you can install the toolkit on it in development mode executing this:

python setup.py develop

Using this method of deployment the toolkit files will be linked instead of copied, so if you make changes on them you won’t need to reinstall the toolkit.

If you want install it in a nomal mode, execute:

python setup.py install

Demo Flask

You’ll need a virtualenv with the toolkit installed on it.

To run the demo you need to install the requirements first. Load your virtualenv and execute:

pip install -r demo-flask/requirements.txt

This will install flask and its dependences. Once it has finished, you have to complete the configuration of the toolkit. You’ll find it at demo-flask/settings.json

Now, with the virtualenv loaded, you can run the demo like this:

cd demo-flask
python index.py

You’ll have the demo running at http://localhost:8000

Content

The flask project contains:

  • *index.py* Is the main flask file, where or the SAML handle take place.
  • *templates*. Is the folder where flask stores the templates of the project. It was implemented a base.html template that is extended by index.html and attrs.html, the templates of our simple demo that shows messages, user attributes when available and login and logout links.
  • *saml* Is a folder that contains the ‘certs’ folder that could be used to store the x509 public and private key, and the saml toolkit settings (settings.json and advanced_settings.json).

SP setup

The Onelogin’s Python Toolkit allows you to provide the settings info in 2 ways: settings files or define a setting dict. In the demo-flask it used the first method.

In the index.py file we define the app.config[‘SAML_PATH’], that will target to the ‘saml’ folder. We require it in order to load the settings files.

First we need to edit the saml/settings.json, configure the SP part and review the metadata of the IdP and complete the IdP info. Later edit the saml/advanced_settings.json files and configure the how the toolkit will work. Check the settings section of this document if you have any doubt.

IdP setup

Once the SP is configured, the metadata of the SP is published at the /metadata url. Based on that info, configure the IdP.

How it works

  1. First time you access to the main view ‘http://localhost:8000’, you can select to login and return to the same view or login and be redirected to /?attrs (attrs view).

  2. When you click:

    2.1 in the first link, we access to /?sso (index view). An AuthNRequest is sent to the IdP, we authenticate at the IdP and then a Response is sent to the SP, specifically the Assertion Consumer Service view: /?acs, notice that a RelayState parameter is set to the url that initiated the process, the index view.

    2.2 in the second link we access to /?attrs (attrs view), we will expetience have the same process described at 2.1 with the diference that as RelayState is set the attrs url.

  3. The SAML Response is processed in the ACS /?acs, if the Response is not valid, the process stops here and a message is shown. Otherwise we are redirected to the RelayState view. a) / or b) /?attrs

  4. We are logged in the app and the user attributes are showed. At this point, we can test the single log out functionality.

The single log out funcionality could be tested by 2 ways.

5.1 SLO Initiated by SP. Click on the "logout" link at the SP, after that a Logout Request is sent to the IdP, the session at the IdP is closed and replies to the SP a Logout Response (sent to the Single Logout Service endpoint). The SLS endpoint /?sls of the SP process the Logout Response and if is valid, close the user session of the local app. Notice that the SLO Workflow starts and ends at the SP.

5.2 SLO Initiated by IdP. In this case, the action takes place on the IdP side, the logout process is initiated at the idP, sends a Logout Request to the SP (SLS endpoint, /?sls). The SLS endpoint of the SP process the Logout Request and if is valid, close the session of the user at the local app and send a Logout Response to the IdP (to the SLS endpoint of the IdP). The IdP receives the Logout Response, process it and close the session at of the IdP. Notice that the SLO Workflow starts and ends at the IdP.

Notice that all the SAML Requests and Responses are handled at a unique view (index) and how GET paramters are used to know the action that must be done.

Demo Django

You’ll need a virtualenv with the toolkit installed on it.

To run the demo you need to install the requirements first. Load your virtualenv and execute:

pip install -r demo-django/requirements.txt

This will install django and its dependences. Once it has finished, you have to complete the configuration of the toolkit.

Later, with the virtualenv loaded, you can run the demo like this:

cd demo-django
python manage.py runserver 0.0.0.0:8000

You’ll have the demo running at http://localhost:8000

Content

The django project contains:

  • *manage.py*. A file that is automatically created in each Django project. Is a thin wrapper around django-admin.py that takes care of putting the project’s package on sys.path and sets the DJANGO_SETTINGS_MODULE environment variable.
  • *saml* Is a folder that contains the ‘certs’ folder that could be used to store the x509 public and private key, and the saml toolkit settings (settings.json and advanced_settings.json).
  • *demo* Is the main folder of the django project, that contains the typical files:
  • *settings.py* Contains the default parameters of a django project except the SAML_FOLDER parameter, that may contain the path where is located the ‘saml’ folder.
  • *urls.py* A file that define url routes. In the demo we defined ‘/’ that is related to the index view, ‘/attrs’ that is related with the attrs view and ‘/metadata’, related to th metadata view.
  • *views.py* This file contains the views of the django project and some aux methods.
  • *wsgi.py* A file that let as deploy django using WSGI, the Python standard for web servers and applications.
  • *templates*. Is the folder where django stores the templates of the project. It was implemented a base.html template that is extended by index.html and attrs.html, the templates of our simple demo that shows messages, user attributes when available and login and logout links.

SP setup

The Onelogin’s Python Toolkit allows you to provide the settings info in 2 ways: settings files or define a setting dict. In the demo-django it used the first method.

After set the SAML_FOLDER in the demo/settings.py, the settings of the python toolkit will be loaded on the django web.

First we need to edit the saml/settings.json, configure the SP part and review the metadata of the IdP and complete the IdP info. Later edit the saml/advanced_settings.json files and configure the how the toolkit will work. Check the settings section of this document if you have any doubt.

IdP setup

Once the SP is configured, the metadata of the SP is published at the /metadata url. Based on that info, configure the IdP.

How it works

This demo works very similar to the flask-demo (We did it intentionally).