Initial commit.

Author: Rebecka Gulliksson

.bumpversion.cfg

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+[bumpversion]
+current_version = 0.0.1
+commit = True
+tag = True
+
+[bumpversion:file:setup.py]
+

.gitignore

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+*.pyc
+*.egg-info
+build/
+dist/
+.idea/

README.md

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+# Flask-pyoidc
+
+This repository contains an example of how to use the [pyoidc](https://github.com/rohe/pyoidc)
+library to provide simple OpenID Connect authentication (using the ["Code Flow"](http://openid.net/specs/openid-connect-core-1_0.html#CodeFlowAuth).
+
+## Usage
+
+The extension support both static and dynamic provider configuration discovery as well as static
+and dynamic client registration. The different modes of provider configuration can be combined in
+any way with the different client registration modes.
+ 
+* Static provider configuration: `OIDCAuthentication(provider_configuration_info=provider_config)`,
+  where `provider_config` is a dictionary containing the [provider metadata](https://openid.net/specs/openid-connect-discovery-1_0.html#ProviderMetadata).
+* Dynamic provider configuration: `OIDCAuthentication(issuer=issuer_url)`, where `issuer_url`
+  is the issuer URL of the provider.
+* Static client registration: `OIDCAuthentication(client_registration_info=client_info)`, where
+  `client_info` is all the [registered metadata](https://openid.net/specs/openid-connect-registration-1_0.html#RegistrationResponse)
+  about the client. The `redirect_uris` registered with the provider MUST include
+  `<flask_url>/redirect_uri`, where `<flask_url>` is the URL for the Flask application.
+  
+
+
+The application using this extension MUST set the following [builtin configuration values of Flask](http://flask.pocoo.org/docs/0.10/config/#builtin-configuration-values):
+
+* `SERVER_NAME` (MUST be the same as `<flask_url>` if using static client registration
+* `SECRET_KEY` (this extension relies on Flask session, which requires `SECRET_KEY`)
+
+Have a look at the example Flask app in [app.py](example/app.py) for an idea of how to use it.

example/app.py

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+import flask
+from flask import Flask, jsonify
+
+from flask_pyoidc import OIDCAuthentication
+
+PORT = 5000
+app = Flask(__name__)
+
+app.config.update({'SERVER_NAME': 'localhost:{}'.format(PORT),
+                   'SECRET_KEY': 'dev_key'})
+auth = OIDCAuthentication(app, issuer="https://localhost:50009")
+
+
+@app.route('/')
+@auth.oidc_auth
+def index():
+    return jsonify(id_token=flask.g.id_token.to_dict(), access_token=flask.g.access_token,
+                   userinfo=flask.g.userinfo.to_dict())
+
+
+if __name__ == '__main__':
+    app.run(port=PORT)

setup.py

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+from setuptools import setup, find_packages
+
+setup(
+        name='Flask-pyoidc',
+        version='0.0.1',
+        packages=find_packages('src'),
+        package_dir={'': 'src'},
+        url='https://github.com/its-dirg/flask-pyoidc',
+        license='Apache 2.0',
+        author='Rebecka Gulliksson',
+        author_email='rebecka.gulliksson@umu.se',
+        description='Flask extension for OpenID Connect authentication.',
+        install_requires=[
+            'oic',
+            'Flask'
+        ]
+)

src/flask_pyoidc.py

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+import functools
+
+import flask
+from flask.helpers import url_for
+from oic.oauth2 import rndstr
+from oic.oic import Client
+from oic.oic.message import ProviderConfigurationResponse, RegistrationRequest, \
+    AuthorizationResponse
+from oic.utils.authn.client import CLIENT_AUTHN_METHOD
+from werkzeug.utils import redirect
+
+
+class OIDCAuthentication(object):
+    def __init__(self, flask_app, client_registration_info=None, issuer=None,
+                 provider_configuration_info=None):
+        self.app = flask_app
+
+        self.client = Client(client_authn_method=CLIENT_AUTHN_METHOD)
+        if not issuer and not provider_configuration_info:
+            raise ValueError(
+                    'Either \'issuer\' (for dynamic discovery) or \'provider_configuration_info\' (for static configuration must be specified.')
+        if issuer and not provider_configuration_info:
+            self.client.provider_config(issuer)
+        else:
+            self.client.handle_provider_config(
+                    ProviderConfigurationResponse(**provider_configuration_info),
+                    provider_configuration_info['issuer'])
+
+        self.client_registration_info = client_registration_info or {}
+        if client_registration_info and 'client_id' in client_registration_info:
+            # static client info provided
+            self.client.store_registration_info(RegistrationRequest(**client_registration_info))
+        else:
+            # do dynamic registration
+            self.app.add_url_rule('/redirect_uri', 'redirect_uri',
+                                  self._handle_authentication_response)
+            with self.app.app_context():
+                self.client_registration_info['redirect_uris'] = url_for('redirect_uri')
+            self.client.register(self.client.provider_info['registration_endpoint'],
+                                 **self.client_registration_info)
+
+        self.callback = None
+
+    def _authenticate(self):
+        if flask.g.get('userinfo', None):
+            return self.callback()
+
+        flask.session['state'] = rndstr()
+        flask.session['nonce'] = rndstr()
+        args = {
+            'client_id': self.client.client_id,
+            'response_type': 'code',
+            'scope': ['openid'],
+            'redirect_uri': self.client.registration_response['redirect_uris'][0],
+            'state': flask.session['state'],
+            'nonce': flask.session['nonce'],
+        }
+
+        auth_req = self.client.construct_AuthorizationRequest(request_args=args)
+        login_url = auth_req.request(self.client.authorization_endpoint)
+        return redirect(login_url)
+
+    def _handle_authentication_response(self):
+        # parse authentication response
+        query_string = flask.request.query_string.decode('utf-8')
+        authn_resp = self.client.parse_response(AuthorizationResponse, info=query_string,
+                                                sformat='urlencoded')
+
+        if authn_resp['state'] != flask.session['state']:
+            raise ValueError('The \'state\' parameter does not match.')
+
+        # do token request
+        args = {
+            'code': authn_resp['code'],
+            'redirect_uri': self.client.registration_response['redirect_uris'][0],
+            'client_id': self.client.client_id,
+            'client_secret': self.client.client_secret
+        }
+        token_resp = self.client.do_access_token_request(scope='openid', state=authn_resp['state'],
+                                                         request_args=args,
+                                                         authn_method='client_secret_basic')
+        id_token = token_resp['id_token']
+        if id_token['nonce'] != flask.session['nonce']:
+            raise ValueError('The \'nonce\' parameter does not match.')
+        access_token = token_resp['access_token']
+
+        # do userinfo request
+        userinfo = self.client.do_user_info_request(state=authn_resp['state'])
+        if userinfo['sub'] != id_token['sub']:
+            raise ValueError('The \'sub\' of userinfo does not match \'sub\' of ID Token.')
+
+        # store the current user
+        flask.g.id_token = id_token
+        flask.g.access_token = access_token
+        flask.g.userinfo = userinfo
+
+        return self.callback()
+
+    def oidc_auth(self, f):
+        self.callback = f
+
+        @functools.wraps(f)
+        def wrapper():
+            return self._authenticate()
+
+        return wrapper