django-mellon/mellon/adapters.py

155 lines
6.5 KiB
Python

import logging
import uuid
from django.core.exceptions import PermissionDenied
from django.contrib import auth
from django.contrib.auth.models import Group
from . import utils, app_settings, models
class DefaultAdapter(object):
def __init__(self, *args, **kwargs):
self.logger = logging.getLogger(__name__)
def get_idp(self, entity_id):
'''Find the first IdP definition matching entity_id'''
for idp in app_settings.IDENTITY_PROVIDERS:
if entity_id == idp['ENTITY_ID']:
return idp
def get_idps(self):
return [idp for idp in app_settings.IDENTITY_PROVIDERS]
def authorize(self, idp, saml_attributes):
if not idp:
return False
required_classref = utils.get_setting(idp, 'AUTHN_CLASSREF')
if required_classref:
given_classref = saml_attributes['authn_context_class_ref']
if given_classref is None or \
given_classref not in required_classref:
raise PermissionDenied
return True
def format_username(self, idp, saml_attributes):
realm = utils.get_setting(idp, 'REALM')
username_template = utils.get_setting(idp, 'USERNAME_TEMPLATE')
try:
username = unicode(username_template).format(
realm=realm, attributes=saml_attributes, idp=idp)[:30]
except ValueError:
self.logger.error(u'invalid username template %r', username_template)
except (AttributeError, KeyError, IndexError), e:
self.logger.error(
u'invalid reference in username template %r: %s', username_template, e)
except Exception, e:
self.logger.exception(u'unknown error when formatting username')
else:
return username
def lookup_user(self, idp, saml_attributes):
User = auth.get_user_model()
name_id = saml_attributes['name_id_content']
issuer = saml_attributes['issuer']
try:
return User.objects.get(saml_identifiers__name_id=name_id,
saml_identifiers__issuer=issuer)
except User.DoesNotExist:
if not utils.get_setting(idp, 'PROVISION'):
self.logger.warning('provisionning disabled, login refused')
return None
username = self.format_username(idp, saml_attributes)
if not username:
self.logger.warning('could not build a username, login refused')
return None
user = User.objects.create(username=uuid.uuid4().hex[:30])
saml_id, created = models.UserSAMLIdentifier.objects.get_or_create(
name_id=name_id, issuer=issuer, defaults={'user': user})
if created:
user.username = username
user.save()
else:
user.delete()
user = saml_id.user
return user
def provision(self, user, idp, saml_attributes):
self.provision_attribute(user, idp, saml_attributes)
self.provision_superuser(user, idp, saml_attributes)
self.provision_groups(user, idp, saml_attributes)
def provision_attribute(self, user, idp, saml_attributes):
realm = utils.get_setting(idp, 'REALM')
attribute_mapping = utils.get_setting(idp, 'ATTRIBUTE_MAPPING')
attribute_set = False
for field, tpl in attribute_mapping.iteritems():
try:
value = unicode(tpl).format(realm=realm, attributes=saml_attributes, idp=idp)
except ValueError:
self.logger.warning(u'invalid attribute mapping template %r', tpl)
except (AttributeError, KeyError, IndexError, ValueError), e:
self.logger.warning(
u'invalid reference in attribute mapping template %r: %s', tpl, e)
else:
attribute_set = True
model_field = user._meta.get_field(field)
if hasattr(model_field, 'max_length'):
value = value[:model_field.max_length]
setattr(user, field, value)
if attribute_set:
user.save()
def provision_superuser(self, user, idp, saml_attributes):
superuser_mapping = utils.get_setting(idp, 'SUPERUSER_MAPPING')
if not superuser_mapping:
return
for key, values in superuser_mapping.iteritems():
if key in saml_attributes:
if not isinstance(values, (tuple, list)):
values = [values]
values = set(values)
attribute_values = saml_attributes[key]
if not isinstance(attribute_values, (tuple, list)):
attribute_values = [attribute_values]
attribute_values = set(attribute_values)
if attribute_values & values:
user.is_staff = True
user.is_superuser = True
user.save()
break
else:
if user.is_superuser or user.is_staff:
user.is_staff = False
user.is_superuser = False
user.save()
def provision_groups(self, user, idp, saml_attributes):
User = user.__class__
group_attribute = utils.get_setting(idp, 'GROUP_ATTRIBUTE')
create_group = utils.get_setting(idp, 'CREATE_GROUP')
if group_attribute in saml_attributes:
values = saml_attributes[group_attribute]
if not isinstance(values, (list, tuple)):
values = [values]
groups = []
for value in set(values):
if create_group:
group, created = Group.objects.get_or_create(name=value)
else:
try:
group = Group.objects.get(name=value)
except Group.DoesNotExist:
continue
groups.append(group)
for group in Group.objects.filter(pk__in=[g.pk for g in groups]).exclude(user=user):
self.logger.info(
u'adding group %s (%s) to user %s (%s)', group, group.pk, user, user.pk)
User.groups.through.objects.get_or_create(group=group, user=user)
qs = User.groups.through.objects.exclude(
group__pk__in=[g.pk for g in groups]).filter(user=user)
for rel in qs:
self.logger.info(u'removing group %s (%s) from user %s (%s)', rel.group,
rel.group.pk, rel.user, rel.user.pk)
qs.delete()