Source code for openstack_auth.utils

# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
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# implied.
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# limitations under the License.

import datetime
import logging
import re

from django.conf import settings
from django.contrib import auth
from django.contrib.auth import middleware
from django.contrib.auth import models
from django.utils import timezone
from keystoneauth1.identity import v2 as v2_auth
from keystoneauth1.identity import v3 as v3_auth
from keystoneauth1 import session
from keystoneauth1 import token_endpoint
from keystoneclient.v2_0 import client as client_v2
from keystoneclient.v3 import client as client_v3
from six.moves.urllib import parse as urlparse


LOG = logging.getLogger(__name__)

_TOKEN_TIMEOUT_MARGIN = getattr(settings, 'TOKEN_TIMEOUT_MARGIN', 0)

"""
We need the request object to get the user, so we'll slightly modify the
existing django.contrib.auth.get_user method. To do so we update the
auth middleware to point to our overridden method.

Calling the "patch_middleware_get_user" method somewhere like our urls.py
file takes care of hooking it in appropriately.
"""


def middleware_get_user(request):
    if not hasattr(request, '_cached_user'):
        request._cached_user = get_user(request)
    return request._cached_user


def get_user(request):
    try:
        user_id = request.session[auth.SESSION_KEY]
        backend_path = request.session[auth.BACKEND_SESSION_KEY]
        backend = auth.load_backend(backend_path)
        backend.request = request
        user = backend.get_user(user_id) or models.AnonymousUser()
    except KeyError:
        user = models.AnonymousUser()
    return user


def patch_middleware_get_user():
    middleware.get_user = middleware_get_user
    auth.get_user = get_user


""" End Monkey-Patching. """


[docs]def is_token_valid(token, margin=None): """Timezone-aware checking of the auth token's expiration timestamp. Returns ``True`` if the token has not yet expired, otherwise ``False``. :param token: The openstack_auth.user.Token instance to check :param margin: A time margin in seconds to subtract from the real token's validity. An example usage is that the token can be valid once the middleware passed, and invalid (timed-out) during a view rendering and this generates authorization errors during the view rendering. A default margin can be set by the TOKEN_TIMEOUT_MARGIN in the django settings. """ expiration = token.expires # In case we get an unparseable expiration timestamp, return False # so you can't have a "forever" token just by breaking the expires param. if expiration is None: return False if margin is None: margin = getattr(settings, 'TOKEN_TIMEOUT_MARGIN', 0) expiration = expiration - datetime.timedelta(seconds=margin) if settings.USE_TZ and timezone.is_naive(expiration): # Presumes that the Keystone is using UTC. expiration = timezone.make_aware(expiration, timezone.utc) return expiration > timezone.now()
# From django.contrib.auth.views # Added in Django 1.4.3, 1.5b2 # Vendored here for compatibility with old Django versions.
[docs]def is_safe_url(url, host=None): """Return ``True`` if the url is a safe redirection. The safe redirection means that it doesn't point to a different host. Always returns ``False`` on an empty url. """ if not url: return False netloc = urlparse.urlparse(url)[1] return not netloc or netloc == host
# DEPRECATED -- Mitaka # This method definition is included to prevent breaking backward compatibility # The original functionality was problematic and has been removed. def remove_project_cache(token): pass # Helper for figuring out keystone version # Implementation will change when API version discovery is available def get_keystone_version(): return getattr(settings, 'OPENSTACK_API_VERSIONS', {}).get('identity', 2.0) def get_session(): insecure = getattr(settings, 'OPENSTACK_SSL_NO_VERIFY', False) verify = getattr(settings, 'OPENSTACK_SSL_CACERT', True) if insecure: verify = False return session.Session(verify=verify) def get_keystone_client(): if get_keystone_version() < 3: return client_v2 else: return client_v3 def is_token_deletion_disabled(): LOG.warning("Deprecated TOKEN_DELETION_DISABLED setting is no longer used") return getattr(settings, 'TOKEN_DELETION_DISABLED', False)
[docs]def is_websso_enabled(): """Websso is supported in Keystone version 3.""" websso_enabled = getattr(settings, 'WEBSSO_ENABLED', False) keystonev3_plus = (get_keystone_version() >= 3) return websso_enabled and keystonev3_plus
[docs]def build_absolute_uri(request, relative_url): """Ensure absolute_uri are relative to WEBROOT.""" webroot = getattr(settings, 'WEBROOT', '') if webroot.endswith("/") and relative_url.startswith("/"): webroot = webroot[:-1] return request.build_absolute_uri(webroot + relative_url)
[docs]def get_websso_url(request, auth_url, websso_auth): """Return the keystone endpoint for initiating WebSSO. Generate the keystone WebSSO endpoint that will redirect the user to the login page of the federated identity provider. Based on the authentication type selected by the user in the login form, it will construct the keystone WebSSO endpoint. :param request: Django http request object. :type request: django.http.HttpRequest :param auth_url: Keystone endpoint configured in the horizon setting. The value is derived from: - OPENSTACK_KEYSTONE_URL - AVAILABLE_REGIONS :type auth_url: string :param websso_auth: Authentication type selected by the user from the login form. The value is derived from the horizon setting WEBSSO_CHOICES. :type websso_auth: string Example of horizon WebSSO setting:: WEBSSO_CHOICES = ( ("credentials", "Keystone Credentials"), ("oidc", "OpenID Connect"), ("saml2", "Security Assertion Markup Language"), ("acme_oidc", "ACME - OpenID Connect"), ("acme_saml2", "ACME - SAML2") ) WEBSSO_IDP_MAPPING = { "acme_oidc": ("acme", "oidc"), "acme_saml2": ("acme", "saml2") } } The value of websso_auth will be looked up in the WEBSSO_IDP_MAPPING dictionary, if a match is found it will return a IdP specific WebSSO endpoint using the values found in the mapping. The value in WEBSSO_IDP_MAPPING is expected to be a tuple formatted as (<idp_id>, <protocol_id>). Using the values found, a IdP/protocol specific URL will be constructed: /auth/OS-FEDERATION/identity_providers/<idp_id> /protocols/<protocol_id>/websso If no value is found from the WEBSSO_IDP_MAPPING dictionary, it will treat the value as the global WebSSO protocol <protocol_id> and construct the WebSSO URL by: /auth/OS-FEDERATION/websso/<protocol_id> :returns: Keystone WebSSO endpoint. :rtype: string """ origin = build_absolute_uri(request, '/auth/websso/') idp_mapping = getattr(settings, 'WEBSSO_IDP_MAPPING', {}) idp_id, protocol_id = idp_mapping.get(websso_auth, (None, websso_auth)) if idp_id: # Use the IDP specific WebSSO endpoint url = ('%s/auth/OS-FEDERATION/identity_providers/%s' '/protocols/%s/websso?origin=%s' % (auth_url, idp_id, protocol_id, origin)) else: # If no IDP mapping found for the identifier, # perform WebSSO by protocol. url = ('%s/auth/OS-FEDERATION/websso/%s?origin=%s' % (auth_url, protocol_id, origin)) return url
[docs]def has_in_url_path(url, subs): """Test if any of `subs` strings is present in the `url` path.""" scheme, netloc, path, query, fragment = urlparse.urlsplit(url) return any([sub in path for sub in subs])
[docs]def url_path_replace(url, old, new, count=None): """Return a copy of url with replaced path. Return a copy of url with all occurrences of old replaced by new in the url path. If the optional argument count is given, only the first count occurrences are replaced. """ args = [] scheme, netloc, path, query, fragment = urlparse.urlsplit(url) if count is not None: args.append(count) return urlparse.urlunsplit(( scheme, netloc, path.replace(old, new, *args), query, fragment))
def url_path_append(url, suffix): scheme, netloc, path, query, fragment = urlparse.urlsplit(url) path = (path + suffix).replace('//', '/') return urlparse.urlunsplit((scheme, netloc, path, query, fragment)) def _augment_url_with_version(auth_url): """Optionally augment auth_url path with version suffix. Check if path component already contains version suffix and if it does not, append version suffix to the end of path, not erasing the previous path contents, since keystone web endpoint (like /identity) could be there. Keystone version needs to be added to endpoint because as of Kilo, the identity URLs returned by Keystone might no longer contain API versions, leaving the version choice up to the user. """ if has_in_url_path(auth_url, ["/v2.0", "/v3"]): return auth_url if get_keystone_version() >= 3: return url_path_append(auth_url, "/v3") else: return url_path_append(auth_url, "/v2.0") # TODO(tsufiev): remove this legacy version as soon as Horizon switches to # the new fix_auth_url_version_prefix() call
[docs]def fix_auth_url_version(auth_url): """Fix up the auth url if an invalid or no version prefix was given. People still give a v2 auth_url even when they specify that they want v3 authentication. Fix the URL to say v3 in this case and add version if it is missing entirely. This should be smarter and use discovery. """ auth_url = _augment_url_with_version(auth_url) if get_keystone_version() >= 3 and has_in_url_path(auth_url, ["/v2.0"]): LOG.warning("The Keystone URL (either in Horizon settings or in " "service catalog) points to a v2.0 Keystone endpoint, " "but v3 is specified as the API version to use by " "Horizon. Using v3 endpoint for authentication.") auth_url = url_path_replace(auth_url, "/v2.0", "/v3", 1) return auth_url
[docs]def fix_auth_url_version_prefix(auth_url): """Fix up the auth url if an invalid or no version prefix was given. People still give a v2 auth_url even when they specify that they want v3 authentication. Fix the URL to say v3 in this case and add version if it is missing entirely. This should be smarter and use discovery. """ auth_url = _augment_url_with_version(auth_url) url_fixed = False if get_keystone_version() >= 3 and has_in_url_path(auth_url, ["/v2.0"]): url_fixed = True auth_url = url_path_replace(auth_url, "/v2.0", "/v3", 1) return auth_url, url_fixed
[docs]def clean_up_auth_url(auth_url): """Clean up the auth url to extract the exact Keystone URL""" # NOTE(mnaser): This drops the query and fragment because we're only # trying to extract the Keystone URL. scheme, netloc, path, query, fragment = urlparse.urlsplit(auth_url) return urlparse.urlunsplit(( scheme, netloc, re.sub(r'/auth.*', '', path), '', ''))
def get_token_auth_plugin(auth_url, token, project_id=None, domain_name=None): if get_keystone_version() >= 3: if domain_name: return v3_auth.Token(auth_url=auth_url, token=token, domain_name=domain_name, reauthenticate=False) else: return v3_auth.Token(auth_url=auth_url, token=token, project_id=project_id, reauthenticate=False) else: return v2_auth.Token(auth_url=auth_url, token=token, tenant_id=project_id, reauthenticate=False) def get_project_list(*args, **kwargs): is_federated = kwargs.get('is_federated', False) sess = kwargs.get('session') or get_session() auth_url, _ = fix_auth_url_version_prefix(kwargs['auth_url']) auth = token_endpoint.Token(auth_url, kwargs['token']) client = get_keystone_client().Client(session=sess, auth=auth) if get_keystone_version() < 3: projects = client.tenants.list() elif is_federated: projects = client.federation.projects.list() else: projects = client.projects.list(user=kwargs.get('user_id')) projects.sort(key=lambda project: project.name.lower()) return projects
[docs]def default_services_region(service_catalog, request=None): """Returns the first endpoint region for first non-identity service. Extracted from the service catalog. """ if service_catalog: available_regions = [get_endpoint_region(endpoint) for service in service_catalog for endpoint in service.get('endpoints', []) if (service.get('type') is not None and service.get('type') != 'identity')] if not available_regions: # this is very likely an incomplete keystone setup LOG.warning('No regions could be found excluding identity.') available_regions = [get_endpoint_region(endpoint) for service in service_catalog for endpoint in service.get('endpoints', [])] if not available_regions: # if there are no region setup for any service endpoint, # this is a critical problem and it's not clear how this occurs LOG.error('No regions can be found in the service catalog.') return None selected_region = None if request: selected_region = request.COOKIES.get('services_region', available_regions[0]) if selected_region not in available_regions: selected_region = available_regions[0] return selected_region return None
[docs]def get_endpoint_region(endpoint): """Common function for getting the region from endpoint. In Keystone V3, region has been deprecated in favor of region_id. This method provides a way to get region that works for both Keystone V2 and V3. """ return endpoint.get('region_id') or endpoint.get('region')
def using_cookie_backed_sessions(): engine = getattr(settings, 'SESSION_ENGINE', '') return "signed_cookies" in engine
[docs]def get_admin_roles(): """Common function for getting the admin roles from settings Returns: Set object including all admin roles. If there is no role, this will return empty. { "foo", "bar", "admin" } """ admin_roles = {role.lower() for role in getattr(settings, 'OPENSTACK_KEYSTONE_ADMIN_ROLES', ['admin'])} return admin_roles
[docs]def get_role_permission(role): """Common function for getting the permission froms arg This format is 'openstack.roles.xxx' and 'xxx' is a real role name. Returns: String like "openstack.roles.admin" If role is None, this will return None. """ return "openstack.roles.%s" % role.lower()
[docs]def get_admin_permissions(): """Common function for getting the admin permissions from settings This format is 'openstack.roles.xxx' and 'xxx' is a real role name. Returns: Set object including all admin permission. If there is no permission, this will return empty. { "openstack.roles.foo", "openstack.roles.bar", "openstack.roles.admin" } """ return {get_role_permission(role) for role in get_admin_roles()}
[docs]def get_client_ip(request): """Return client ip address using SECURE_PROXY_ADDR_HEADER variable. If not present or not defined on settings then REMOTE_ADDR is used. :param request: Django http request object. :type request: django.http.HttpRequest :returns: Possible client ip address :rtype: string """ _SECURE_PROXY_ADDR_HEADER = getattr( settings, 'SECURE_PROXY_ADDR_HEADER', False ) if _SECURE_PROXY_ADDR_HEADER: return request.META.get( _SECURE_PROXY_ADDR_HEADER, request.META.get('REMOTE_ADDR') ) return request.META.get('REMOTE_ADDR')
[docs]def store_initial_k2k_session(auth_url, request, scoped_auth_ref, unscoped_auth_ref): """Stores session variables if there are k2k service providers This stores variables related to Keystone2Keystone federation. This function gets skipped if there are no Keystone service providers. An unscoped token to the identity provider keystone gets stored so that it can be used to do federated login into the service providers when switching keystone providers. The settings file can be configured to set the display name of the local (identity provider) keystone by setting KEYSTONE_PROVIDER_IDP_NAME. The KEYSTONE_PROVIDER_IDP_ID settings variable is used for comparison against the service providers. It should not conflict with any of the service provider ids. :param auth_url: base token auth url :param request: Django http request object :param scoped_auth_ref: Scoped Keystone access info object :param unscoped_auth_ref: Unscoped Keystone access info object """ keystone_provider_id = request.session.get('keystone_provider_id', None) if keystone_provider_id: return None providers = getattr(scoped_auth_ref, 'service_providers', None) if providers: providers = getattr(providers, '_service_providers', None) if providers: keystone_idp_name = getattr(settings, 'KEYSTONE_PROVIDER_IDP_NAME', 'Local Keystone') keystone_idp_id = getattr( settings, 'KEYSTONE_PROVIDER_IDP_ID', 'localkeystone') keystone_identity_provider = {'name': keystone_idp_name, 'id': keystone_idp_id} # (edtubill) We will use the IDs as the display names # We may want to be able to set display names in the future. keystone_providers = [ {'name': provider_id, 'id': provider_id} for provider_id in providers] keystone_providers.append(keystone_identity_provider) # We treat the Keystone idp ID as None request.session['keystone_provider_id'] = keystone_idp_id request.session['keystone_providers'] = keystone_providers request.session['k2k_base_unscoped_token'] =\ unscoped_auth_ref.auth_token request.session['k2k_auth_url'] = auth_url