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__init__.py
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__init__.py
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# Copyright (c) 2014-2015, Erica Ehrhardt
# Copyright (c) 2016, Patrick Uiterwijk <patrick@puiterwijk.org>
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# * Redistributions of source code must retain the above copyright notice, this
# list of conditions and the following disclaimer.
#
# * Redistributions in binary form must reproduce the above copyright notice,
# this list of conditions and the following disclaimer in the documentation
# and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
from functools import wraps
import os
import json
from base64 import b64encode, b64decode, urlsafe_b64encode, urlsafe_b64decode
import time
from copy import copy
import logging
from warnings import warn
import calendar
from six.moves.urllib.parse import urlencode
from flask import request, session, redirect, url_for, g, current_app, abort
from oauth2client.client import flow_from_clientsecrets, OAuth2WebServerFlow,\
AccessTokenRefreshError, OAuth2Credentials
import httplib2
from itsdangerous import JSONWebSignatureSerializer, BadSignature
__all__ = ['OpenIDConnect', 'MemoryCredentials']
logger = logging.getLogger(__name__)
def _json_loads(content):
if not isinstance(content, str):
content = content.decode('utf-8')
return json.loads(content)
class MemoryCredentials(dict):
"""
Non-persistent local credentials store.
Use this if you only have one app server, and don't mind making everyone
log in again after a restart.
"""
pass
class DummySecretsCache(object):
"""
oauth2client secrets cache
"""
def __init__(self, client_secrets):
self.client_secrets = client_secrets
def get(self, filename, namespace):
return self.client_secrets
class ErrStr(str):
"""
This is a class to work around the time I made a terrible API decision.
Basically, the validate_token() function returns a boolean True if all went
right, but a string with an error message if something went wrong.
The problem here is that this means that "if validate_token(...)" will
always be True, even with an invalid token, and users had to do
"if validate_token(...) is True:".
This is counter-intuitive, so let's "fix" this by returning instances of
this ErrStr class, which are basic strings except for their bool() results:
they return False.
"""
def __nonzero__(self):
"""The py2 method for bool()."""
return False
def __bool__(self):
"""The py3 method for bool()."""
return False
GOOGLE_ISSUERS = ['accounts.google.com', 'https://accounts.google.com']
class OpenIDConnect(object):
"""
The core OpenID Connect client object.
"""
def __init__(self, app=None, credentials_store=None, http=None, time=None,
urandom=None):
self.credentials_store = credentials_store\
if credentials_store is not None\
else MemoryCredentials()
if http is not None:
warn('HTTP argument is deprecated and unused', DeprecationWarning)
if time is not None:
warn('time argument is deprecated and unused', DeprecationWarning)
if urandom is not None:
warn('urandom argument is deprecated and unused',
DeprecationWarning)
# By default, we do not have a custom callback
self._custom_callback = None
# get stuff from the app's config, which may override stuff set above
if app is not None:
self.init_app(app)
def init_app(self, app):
"""
Do setup that requires a Flask app.
:param app: The application to initialize.
:type app: Flask
"""
secrets = self.load_secrets(app)
self.client_secrets = list(secrets.values())[0]
secrets_cache = DummySecretsCache(secrets)
# Set some default configuration options
app.config.setdefault('OIDC_SCOPES', ['openid', 'email'])
app.config.setdefault('OIDC_GOOGLE_APPS_DOMAIN', None)
app.config.setdefault('OIDC_ID_TOKEN_COOKIE_NAME', 'oidc_id_token')
app.config.setdefault('OIDC_ID_TOKEN_COOKIE_PATH', '/')
app.config.setdefault('OIDC_ID_TOKEN_COOKIE_TTL', 7 * 86400) # 7 days
# should ONLY be turned off for local debugging
app.config.setdefault('OIDC_COOKIE_SECURE', True)
app.config.setdefault('OIDC_VALID_ISSUERS',
(self.client_secrets.get('issuer') or
GOOGLE_ISSUERS))
app.config.setdefault('OIDC_CLOCK_SKEW', 60) # 1 minute
app.config.setdefault('OIDC_REQUIRE_VERIFIED_EMAIL', False)
app.config.setdefault('OIDC_OPENID_REALM', None)
app.config.setdefault('OIDC_USER_INFO_ENABLED', True)
app.config.setdefault('OIDC_CALLBACK_ROUTE', '/oidc_callback')
app.config.setdefault('OVERWRITE_REDIRECT_URI', False)
app.config.setdefault("OIDC_EXTRA_REQUEST_AUTH_PARAMS", {})
# Configuration for resource servers
app.config.setdefault('OIDC_RESOURCE_SERVER_ONLY', False)
app.config.setdefault('OIDC_RESOURCE_CHECK_AUD', False)
# We use client_secret_post, because that's what the Google
# oauth2client library defaults to
app.config.setdefault('OIDC_INTROSPECTION_AUTH_METHOD', 'client_secret_post')
app.config.setdefault('OIDC_TOKEN_TYPE_HINT', 'access_token')
if not 'openid' in app.config['OIDC_SCOPES']:
raise ValueError('The value "openid" must be in the OIDC_SCOPES')
# register callback route and cookie-setting decorator
if not app.config['OIDC_RESOURCE_SERVER_ONLY']:
app.route(app.config['OIDC_CALLBACK_ROUTE'])(self._oidc_callback)
app.before_request(self._before_request)
app.after_request(self._after_request)
# Initialize oauth2client
self.flow = flow_from_clientsecrets(
app.config['OIDC_CLIENT_SECRETS'],
scope=app.config['OIDC_SCOPES'],
cache=secrets_cache)
assert isinstance(self.flow, OAuth2WebServerFlow)
# create signers using the Flask secret key
self.extra_data_serializer = JSONWebSignatureSerializer(
app.config['SECRET_KEY'], salt='flask-oidc-extra-data')
self.cookie_serializer = JSONWebSignatureSerializer(
app.config['SECRET_KEY'], salt='flask-oidc-cookie')
try:
self.credentials_store = app.config['OIDC_CREDENTIALS_STORE']
except KeyError:
pass
def load_secrets(self, app):
# Load client_secrets.json to pre-initialize some configuration
content = app.config['OIDC_CLIENT_SECRETS']
if isinstance(content, dict):
return content
else:
return _json_loads(open(content, 'r').read())
@property
def user_loggedin(self):
"""
Represents whether the user is currently logged in.
Returns:
bool: Whether the user is logged in with Flask-OIDC.
.. versionadded:: 1.0
"""
return g.oidc_id_token is not None
def user_getfield(self, field, access_token=None):
"""
Request a single field of information about the user.
:param field: The name of the field requested.
:type field: str
:returns: The value of the field. Depending on the type, this may be
a string, list, dict, or something else.
:rtype: object
.. versionadded:: 1.0
"""
info = self.user_getinfo([field], access_token)
return info.get(field)
def user_getinfo(self, fields, access_token=None):
"""
Request multiple fields of information about the user.
:param fields: The names of the fields requested.
:type fields: list
:returns: The values of the current user for the fields requested.
The keys are the field names, values are the values of the
fields as indicated by the OpenID Provider. Note that fields
that were not provided by the Provider are absent.
:rtype: dict
:raises Exception: If the user was not authenticated. Check this with
user_loggedin.
.. versionadded:: 1.0
"""
if g.oidc_id_token is None and access_token is None:
raise Exception('User was not authenticated')
info = {}
all_info = None
for field in fields:
if access_token is None and field in g.oidc_id_token:
info[field] = g.oidc_id_token[field]
elif current_app.config['OIDC_USER_INFO_ENABLED']:
# This was not in the id_token. Let's get user information
if all_info is None:
all_info = self._retrieve_userinfo(access_token)
if all_info is None:
# To make sure we don't retry for every field
all_info = {}
if field in all_info:
info[field] = all_info[field]
else:
# We didn't get this information
pass
return info
def get_access_token(self):
"""Method to return the current requests' access_token.
:returns: Access token or None
:rtype: str
.. versionadded:: 1.2
"""
try:
credentials = OAuth2Credentials.from_json(
self.credentials_store[g.oidc_id_token['sub']])
return credentials.access_token
except KeyError:
logger.debug("Expired ID token, credentials missing",
exc_info=True)
return None
def get_refresh_token(self):
"""Method to return the current requests' refresh_token.
:returns: Access token or None
:rtype: str
.. versionadded:: 1.2
"""
try:
credentials = OAuth2Credentials.from_json(
self.credentials_store[g.oidc_id_token['sub']])
return credentials.refresh_token
except KeyError:
logger.debug("Expired ID token, credentials missing",
exc_info=True)
return None
def _retrieve_userinfo(self, access_token=None):
"""
Requests extra user information from the Provider's UserInfo and
returns the result.
:returns: The contents of the UserInfo endpoint.
:rtype: dict
"""
if 'userinfo_uri' not in self.client_secrets:
logger.debug('Userinfo uri not specified')
raise AssertionError('UserInfo URI not specified')
# Cache the info from this request
if '_oidc_userinfo' in g:
return g._oidc_userinfo
http = httplib2.Http()
if access_token is None:
try:
credentials = OAuth2Credentials.from_json(
self.credentials_store[g.oidc_id_token['sub']])
except KeyError:
logger.debug("Expired ID token, credentials missing",
exc_info=True)
return None
credentials.authorize(http)
resp, content = http.request(self.client_secrets['userinfo_uri'])
else:
# We have been manually overriden with an access token
resp, content = http.request(
self.client_secrets['userinfo_uri'],
"POST",
body=urlencode({"access_token": access_token}),
headers={'Content-Type': 'application/x-www-form-urlencoded'})
logger.debug('Retrieved user info: %s' % content)
info = _json_loads(content)
g._oidc_userinfo = info
return info
def get_cookie_id_token(self):
"""
.. deprecated:: 1.0
Use :func:`user_getinfo` instead.
"""
warn('You are using a deprecated function (get_cookie_id_token). '
'Please reconsider using this', DeprecationWarning)
return self._get_cookie_id_token()
def _get_cookie_id_token(self):
try:
id_token_cookie = request.cookies.get(current_app.config[
'OIDC_ID_TOKEN_COOKIE_NAME'])
if not id_token_cookie:
# Do not error if we were unable to get the cookie.
# The user can debug this themselves.
return None
return self.cookie_serializer.loads(id_token_cookie)
except SignatureExpired:
logger.debug("Invalid ID token cookie", exc_info=True)
return None
except BadSignature:
logger.info("Signature invalid for ID token cookie", exc_info=True)
return None
def set_cookie_id_token(self, id_token):
"""
.. deprecated:: 1.0
"""
warn('You are using a deprecated function (set_cookie_id_token). '
'Please reconsider using this', DeprecationWarning)
return self._set_cookie_id_token(id_token)
def _set_cookie_id_token(self, id_token):
"""
Cooperates with @after_request to set a new ID token cookie.
"""
g.oidc_id_token = id_token
g.oidc_id_token_dirty = True
def _after_request(self, response):
"""
Set a new ID token cookie if the ID token has changed.
"""
# This means that if either the new or the old are False, we set
# insecure cookies.
# We don't define OIDC_ID_TOKEN_COOKIE_SECURE in init_app, because we
# don't want people to find it easily.
cookie_secure = (current_app.config['OIDC_COOKIE_SECURE'] and
current_app.config.get('OIDC_ID_TOKEN_COOKIE_SECURE',
True))
if getattr(g, 'oidc_id_token_dirty', False):
if g.oidc_id_token:
signed_id_token = self.cookie_serializer.dumps(g.oidc_id_token)
response.set_cookie(
current_app.config['OIDC_ID_TOKEN_COOKIE_NAME'],
signed_id_token,
secure=cookie_secure,
httponly=True,
max_age=current_app.config['OIDC_ID_TOKEN_COOKIE_TTL'])
else:
# This was a log out
response.set_cookie(
current_app.config['OIDC_ID_TOKEN_COOKIE_NAME'],
'',
path=current_app.config['OIDC_ID_TOKEN_COOKIE_PATH'],
secure=cookie_secure,
httponly=True,
expires=0)
return response
def _before_request(self):
g.oidc_id_token = None
self.authenticate_or_redirect()
def authenticate_or_redirect(self):
"""
Helper function suitable for @app.before_request and @check.
Sets g.oidc_id_token to the ID token if the user has successfully
authenticated, else returns a redirect object so they can go try
to authenticate.
:returns: A redirect object, or None if the user is logged in.
:rtype: Redirect
.. deprecated:: 1.0
Use :func:`require_login` instead.
"""
# the auth callback and error pages don't need user to be authenticated
if request.endpoint in frozenset(['_oidc_callback', '_oidc_error']):
return None
# retrieve signed ID token cookie
id_token = self._get_cookie_id_token()
if id_token is None:
return self.redirect_to_auth_server(request.url)
# ID token expired
# when Google is the IdP, this happens after one hour
if time.time() >= id_token['exp']:
# get credentials from store
try:
credentials = OAuth2Credentials.from_json(
self.credentials_store[id_token['sub']])
except KeyError:
logger.debug("Expired ID token, credentials missing",
exc_info=True)
return self.redirect_to_auth_server(request.url)
# refresh and store credentials
try:
credentials.refresh(httplib2.Http())
if credentials.id_token:
id_token = credentials.id_token
else:
# It is not guaranteed that we will get a new ID Token on
# refresh, so if we do not, let's just update the id token
# expiry field and reuse the existing ID Token.
if credentials.token_expiry is None:
logger.debug('Expired ID token, no new expiry. Falling'
' back to assuming 1 hour')
id_token['exp'] = time.time() + 3600
else:
id_token['exp'] = calendar.timegm(
credentials.token_expiry.timetuple())
self.credentials_store[id_token['sub']] = credentials.to_json()
self._set_cookie_id_token(id_token)
except AccessTokenRefreshError:
# Can't refresh. Wipe credentials and redirect user to IdP
# for re-authentication.
logger.debug("Expired ID token, can't refresh credentials",
exc_info=True)
del self.credentials_store[id_token['sub']]
return self.redirect_to_auth_server(request.url)
# make ID token available to views
g.oidc_id_token = id_token
return None
def require_login(self, view_func):
"""
Use this to decorate view functions that require a user to be logged
in. If the user is not already logged in, they will be sent to the
Provider to log in, after which they will be returned.
.. versionadded:: 1.0
This was :func:`check` before.
"""
@wraps(view_func)
def decorated(*args, **kwargs):
if g.oidc_id_token is None:
return self.redirect_to_auth_server(request.url)
return view_func(*args, **kwargs)
return decorated
# Backwards compatibility
check = require_login
"""
.. deprecated:: 1.0
Use :func:`require_login` instead.
"""
def require_keycloak_role(self, client, role):
"""
Function to check for a KeyCloak client role in JWT access token.
This is intended to be replaced with a more generic 'require this value
in token or claims' system, at which point backwards compatibility will
be added.
.. versionadded:: 1.5.0
"""
def wrapper(view_func):
@wraps(view_func)
def decorated(*args, **kwargs):
pre, tkn, post = self.get_access_token().split('.')
access_token = json.loads(b64decode(tkn))
if role in access_token['resource_access'][client]['roles']:
return view_func(*args, **kwargs)
else:
return abort(403)
return decorated
return wrapper
def flow_for_request(self):
"""
.. deprecated:: 1.0
Use :func:`require_login` instead.
"""
warn('You are using a deprecated function (flow_for_request). '
'Please reconsider using this', DeprecationWarning)
return self._flow_for_request()
def _flow_for_request(self):
"""
Build a flow with the correct absolute callback URL for this request.
:return:
"""
flow = copy(self.flow)
redirect_uri = current_app.config['OVERWRITE_REDIRECT_URI']
if not redirect_uri:
flow.redirect_uri = url_for('_oidc_callback', _external=True)
else:
flow.redirect_uri = redirect_uri
return flow
def redirect_to_auth_server(self, destination=None, customstate=None):
"""
Set a CSRF token in the session, and redirect to the IdP.
:param destination: The page that the user was going to,
before we noticed they weren't logged in.
:type destination: Url to return the client to if a custom handler is
not used. Not available with custom callback.
:param customstate: The custom data passed via the ODIC state.
Note that this only works with a custom_callback, and this will
ignore destination.
:type customstate: Anything that can be serialized
:returns: A redirect response to start the login process.
:rtype: Flask Response
.. deprecated:: 1.0
Use :func:`require_login` instead.
"""
if not self._custom_callback and customstate:
raise ValueError('Custom State is only avilable with a custom '
'handler')
if 'oidc_csrf_token' not in session:
csrf_token = urlsafe_b64encode(os.urandom(24)).decode('utf-8')
session['oidc_csrf_token'] = csrf_token
state = {
'csrf_token': session['oidc_csrf_token'],
}
statefield = 'destination'
statevalue = destination
if customstate is not None:
statefield = 'custom'
statevalue = customstate
state[statefield] = self.extra_data_serializer.dumps(
statevalue).decode('utf-8')
extra_params = {
'state': urlsafe_b64encode(json.dumps(state).encode('utf-8')),
}
extra_params.update(current_app.config['OIDC_EXTRA_REQUEST_AUTH_PARAMS'])
if current_app.config['OIDC_GOOGLE_APPS_DOMAIN']:
extra_params['hd'] = current_app.config['OIDC_GOOGLE_APPS_DOMAIN']
if current_app.config['OIDC_OPENID_REALM']:
extra_params['openid.realm'] = current_app.config[
'OIDC_OPENID_REALM']
flow = self._flow_for_request()
auth_url = '{url}&{extra_params}'.format(
url=flow.step1_get_authorize_url(),
extra_params=urlencode(extra_params))
# if the user has an ID token, it's invalid, or we wouldn't be here
self._set_cookie_id_token(None)
return redirect(auth_url)
def _is_id_token_valid(self, id_token):
"""
Check if `id_token` is a current ID token for this application,
was issued by the Apps domain we expected,
and that the email address has been verified.
@see: http://openid.net/specs/openid-connect-core-1_0.html#IDTokenValidation
"""
if not id_token:
return False
# step 2: check issuer
if id_token['iss'] not in current_app.config['OIDC_VALID_ISSUERS']:
logger.error('id_token issued by non-trusted issuer: %s'
% id_token['iss'])
return False
if isinstance(id_token['aud'], list):
# step 3 for audience list
if self.flow.client_id not in id_token['aud']:
logger.error('We are not a valid audience')
return False
# step 4
if 'azp' not in id_token and len(id_token['aud']) > 1:
logger.error('Multiple audiences and not authorized party')
return False
else:
# step 3 for single audience
if id_token['aud'] != self.flow.client_id:
logger.error('We are not the audience')
return False
# step 5
if 'azp' in id_token and id_token['azp'] != self.flow.client_id:
logger.error('Authorized Party is not us')
return False
# step 6-8: TLS checked
# step 9: check exp
if int(time.time()) >= int(id_token['exp']):
logger.error('Token has expired')
return False
# step 10: check iat
if id_token['iat'] < (time.time() -
current_app.config['OIDC_CLOCK_SKEW']):
logger.error('Token issued in the past')
return False
# (not required if using HTTPS?) step 11: check nonce
# step 12-13: not requested acr or auth_time, so not needed to test
# additional steps specific to our usage
if current_app.config['OIDC_GOOGLE_APPS_DOMAIN'] and \
id_token.get('hd') != current_app.config[
'OIDC_GOOGLE_APPS_DOMAIN']:
logger.error('Invalid google apps domain')
return False
if not id_token.get('email_verified', False) and \
current_app.config['OIDC_REQUIRE_VERIFIED_EMAIL']:
logger.error('Email not verified')
return False
return True
WRONG_GOOGLE_APPS_DOMAIN = 'WRONG_GOOGLE_APPS_DOMAIN'
def custom_callback(self, view_func):
"""
Wrapper function to use a custom callback.
The custom OIDC callback will get the custom state field passed in with
redirect_to_auth_server.
"""
@wraps(view_func)
def decorated(*args, **kwargs):
plainreturn, data = self._process_callback('custom')
if plainreturn:
return data
else:
return view_func(data, *args, **kwargs)
self._custom_callback = decorated
return decorated
def _oidc_callback(self):
plainreturn, data = self._process_callback('destination')
if plainreturn:
return data
else:
return redirect(data)
def _process_callback(self, statefield):
"""
Exchange the auth code for actual credentials,
then redirect to the originally requested page.
"""
# retrieve session and callback variables
try:
session_csrf_token = session.get('oidc_csrf_token')
state = _json_loads(urlsafe_b64decode(request.args['state'].encode('utf-8')))
csrf_token = state['csrf_token']
code = request.args['code']
except (KeyError, ValueError):
logger.debug("Can't retrieve CSRF token, state, or code",
exc_info=True)
return True, self._oidc_error()
# check callback CSRF token passed to IdP
# against session CSRF token held by user
if csrf_token != session_csrf_token:
logger.debug("CSRF token mismatch")
return True, self._oidc_error()
# make a request to IdP to exchange the auth code for OAuth credentials
flow = self._flow_for_request()
credentials = flow.step2_exchange(code)
id_token = credentials.id_token
if not self._is_id_token_valid(id_token):
logger.debug("Invalid ID token")
if id_token.get('hd') != current_app.config[
'OIDC_GOOGLE_APPS_DOMAIN']:
return True, self._oidc_error(
"You must log in with an account from the {0} domain."
.format(current_app.config['OIDC_GOOGLE_APPS_DOMAIN']),
self.WRONG_GOOGLE_APPS_DOMAIN)
return True, self._oidc_error()
# store credentials by subject
# when Google is the IdP, the subject is their G+ account number
self.credentials_store[id_token['sub']] = credentials.to_json()
# Retrieve the extra statefield data
try:
response = self.extra_data_serializer.loads(state[statefield])
except BadSignature:
logger.error('State field was invalid')
return True, self._oidc_error()
# set a persistent signed cookie containing the ID token
# and redirect to the final destination
self._set_cookie_id_token(id_token)
return False, response
def _oidc_error(self, message='Not Authorized', code=None):
return (message, 401, {
'Content-Type': 'text/plain',
})
def logout(self):
"""
Request the browser to please forget the cookie we set, to clear the
current session.
Note that as described in [1], this will not log out in the case of a
browser that doesn't clear cookies when requested to, and the user
could be automatically logged in when they hit any authenticated
endpoint.
[1]: https://github.com/puiterwijk/flask-oidc/issues/5#issuecomment-86187023
.. versionadded:: 1.0
"""
# TODO: Add single logout
self._set_cookie_id_token(None)
# Below here is for resource servers to validate tokens
def validate_token(self, token, scopes_required=None):
"""
This function can be used to validate tokens.
Note that this only works if a token introspection url is configured,
as that URL will be queried for the validity and scopes of a token.
:param scopes_required: List of scopes that are required to be
granted by the token before returning True.
:type scopes_required: list
:returns: True if the token was valid and contained the required
scopes. An ErrStr (subclass of string for which bool() is False) if
an error occured.
:rtype: Boolean or String
.. versionadded:: 1.1
"""
valid = self._validate_token(token, scopes_required)
if valid is True:
return True
else:
return ErrStr(valid)
def _validate_token(self, token, scopes_required=None):
"""The actual implementation of validate_token."""
if scopes_required is None:
scopes_required = []
scopes_required = set(scopes_required)
token_info = None
valid_token = False
has_required_scopes = False
if token:
try:
token_info = self._get_token_info(token)
except Exception as ex:
token_info = {'active': False}
logger.error('ERROR: Unable to get token info')
logger.error(str(ex))
valid_token = token_info.get('active', False)
if 'aud' in token_info and \
current_app.config['OIDC_RESOURCE_CHECK_AUD']:
valid_audience = False
aud = token_info['aud']
clid = self.client_secrets['client_id']
if isinstance(aud, list):
valid_audience = clid in aud
else:
valid_audience = clid == aud
if not valid_audience:
logger.error('Refused token because of invalid '
'audience')
valid_token = False
if valid_token:
token_scopes = token_info.get('scope', '').split(' ')
else:
token_scopes = []
has_required_scopes = scopes_required.issubset(
set(token_scopes))
if not has_required_scopes:
logger.debug('Token missed required scopes')
if (valid_token and has_required_scopes):
g.oidc_token_info = token_info
return True
if not valid_token:
return 'Token required but invalid'
elif not has_required_scopes:
return 'Token does not have required scopes'
else:
return 'Something went wrong checking your token'
def accept_token(self, require_token=False, scopes_required=None,
render_errors=True):
"""
Use this to decorate view functions that should accept OAuth2 tokens,
this will most likely apply to API functions.
Tokens are accepted as part of the query URL (access_token value) or
a POST form value (access_token).
Note that this only works if a token introspection url is configured,
as that URL will be queried for the validity and scopes of a token.
:param require_token: Whether a token is required for the current
function. If this is True, we will abort the request if there
was no token provided.
:type require_token: bool
:param scopes_required: List of scopes that are required to be
granted by the token before being allowed to call the protected
function.
:type scopes_required: list
:param render_errors: Whether or not to eagerly render error objects
as JSON API responses. Set to False to pass the error object back
unmodified for later rendering.
:type render_errors: callback(obj) or None
.. versionadded:: 1.0
"""
def wrapper(view_func):
@wraps(view_func)
def decorated(*args, **kwargs):
token = None
if 'Authorization' in request.headers and request.headers['Authorization'].startswith('Bearer '):
token = request.headers['Authorization'].split(None,1)[1].strip()
if 'access_token' in request.form:
token = request.form['access_token']
elif 'access_token' in request.args:
token = request.args['access_token']
validity = self.validate_token(token, scopes_required)
if (validity is True) or (not require_token):
return view_func(*args, **kwargs)
else:
response_body = {'error': 'invalid_token',
'error_description': validity}
if render_errors:
response_body = json.dumps(response_body)
return response_body, 401, {'WWW-Authenticate': 'Bearer'}
return decorated
return wrapper
def _get_token_info(self, token):
# We hardcode to use client_secret_post, because that's what the Google
# oauth2client library defaults to
request = {'token': token}
headers = {'Content-type': 'application/x-www-form-urlencoded'}
hint = current_app.config['OIDC_TOKEN_TYPE_HINT']
if hint != 'none':
request['token_type_hint'] = hint
auth_method = current_app.config['OIDC_INTROSPECTION_AUTH_METHOD']
if (auth_method == 'client_secret_basic'):
basic_auth_string = '%s:%s' % (self.client_secrets['client_id'], self.client_secrets['client_secret'])
basic_auth_bytes = bytearray(basic_auth_string, 'utf-8')
headers['Authorization'] = 'Basic %s' % b64encode(basic_auth_bytes).decode('utf-8')
elif (auth_method == 'bearer'):
headers['Authorization'] = 'Bearer %s' % token
elif (auth_method == 'client_secret_post'):
request['client_id'] = self.client_secrets['client_id']
if self.client_secrets['client_secret'] is not None:
request['client_secret'] = self.client_secrets['client_secret']
resp, content = httplib2.Http().request(
self.client_secrets['token_introspection_uri'], 'POST',
urlencode(request), headers=headers)
# TODO: Cache this reply
return _json_loads(content)