django-cas-server/cas_server/views.py

1153 lines
46 KiB
Python

# -*- coding: utf-8 -*-
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU General Public License version 3 for
# more details.
#
# You should have received a copy of the GNU General Public License version 3
# along with this program; if not, write to the Free Software Foundation, Inc., 51
# Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#
# (c) 2015-2016 Valentin Samir
"""views for the app"""
from .default_settings import settings
from django.shortcuts import render, redirect
from django.core.urlresolvers import reverse
from django.http import HttpResponse, HttpResponseRedirect
from django.contrib import messages
from django.utils.decorators import method_decorator
from django.utils.translation import ugettext as _
from django.utils import timezone
from django.views.decorators.csrf import csrf_exempt
from django.middleware.csrf import CsrfViewMiddleware
from django.views.generic import View
from django.utils.encoding import python_2_unicode_compatible
import re
import logging
import pprint
import requests
from lxml import etree
from datetime import timedelta
from importlib import import_module
import cas_server.utils as utils
import cas_server.forms as forms
import cas_server.models as models
from .utils import json_response
from .models import ServiceTicket, ProxyTicket, ProxyGrantingTicket
from .models import ServicePattern, FederatedIendityProvider, FederatedUser
from .federate import CASFederateValidateUser
SessionStore = import_module(settings.SESSION_ENGINE).SessionStore
logger = logging.getLogger(__name__)
class AttributesMixin(object):
"""mixin for the attributs methode"""
# pylint: disable=too-few-public-methods
def attributes(self):
"""regerate attributes list for template rendering"""
attributes = []
for key, value in self.ticket.attributs.items():
if isinstance(value, list):
for elt in value:
attributes.append((key, elt))
else:
attributes.append((key, value))
return attributes
class LogoutMixin(object):
"""destroy CAS session utils"""
def logout(self, all_session=False):
"""effectively destroy CAS session"""
session_nb = 0
username = self.request.session.get("username")
if username:
if all_session:
logger.info("Logging out user %s from all of they sessions." % username)
else:
logger.info("Logging out user %s." % username)
# logout the user from the current session
try:
user = models.User.objects.get(
username=username,
session_key=self.request.session.session_key
)
if settings.CAS_FEDERATE:
models.FederateSLO.objects.filter(
username=username,
session_key=self.request.session.session_key
).delete()
self.request.session.flush()
user.logout(self.request)
user.delete()
session_nb += 1
except models.User.DoesNotExist:
# if user not found in database, flush the session anyway
self.request.session.flush()
# If all_session is set logout user from alternative sessions
if all_session:
for user in models.User.objects.filter(username=username):
session = SessionStore(session_key=user.session_key)
session.flush()
user.logout(self.request)
user.delete()
session_nb += 1
logger.info("User %s logged out" % username)
return session_nb
class LogoutView(View, LogoutMixin):
"""destroy CAS session (logout) view"""
request = None
service = None
def init_get(self, request):
"""Initialize GET received parameters"""
self.request = request
self.service = request.GET.get('service')
self.url = request.GET.get('url')
self.ajax = settings.CAS_ENABLE_AJAX_AUTH and 'HTTP_X_AJAX' in request.META
def get(self, request, *args, **kwargs):
"""methode called on GET request on this view"""
logger.info("logout requested")
self.init_get(request)
# if CAS federation mode is enable, bakup the provider before flushing the sessions
if settings.CAS_FEDERATE:
try:
user = FederatedUser.get_from_federated_username(
self.request.session.get("username")
)
auth = CASFederateValidateUser(user.provider, service_url="")
except FederatedUser.DoesNotExist:
auth = None
session_nb = self.logout(self.request.GET.get("all"))
# if CAS federation mode is enable, redirect to user CAS logout page
if settings.CAS_FEDERATE:
if auth is not None:
params = utils.copy_params(request.GET)
url = auth.get_logout_url()
return HttpResponseRedirect(utils.update_url(url, params))
# if service is set, redirect to service after logout
if self.service:
list(messages.get_messages(request)) # clean messages before leaving the django app
return HttpResponseRedirect(self.service)
elif self.url:
list(messages.get_messages(request)) # clean messages before leaving the django app
return HttpResponseRedirect(self.url)
# else redirect to login page
else:
if session_nb == 1:
logout_msg = _(
"<h3>Logout successful</h3>"
"You have successfully logged out from the Central Authentication Service. "
"For security reasons, exit your web browser."
)
elif session_nb > 1:
logout_msg = _(
"<h3>Logout successful</h3>"
"You have successfully logged out from %s sessions of the Central "
"Authentication Service. "
"For security reasons, exit your web browser."
) % session_nb
else:
logout_msg = _(
"<h3>Logout successful</h3>"
"You were already logged out from the Central Authentication Service. "
"For security reasons, exit your web browser."
)
if settings.CAS_REDIRECT_TO_LOGIN_AFTER_LOGOUT:
messages.add_message(request, messages.SUCCESS, logout_msg)
if self.ajax:
url = reverse("cas_server:login")
data = {
'status': 'success',
'detail': 'logout',
'url': url,
'session_nb': session_nb
}
return json_response(request, data)
else:
return redirect("cas_server:login")
else:
if self.ajax:
data = {'status': 'success', 'detail': 'logout', 'session_nb': session_nb}
return json_response(request, data)
else:
return render(
request,
settings.CAS_LOGOUT_TEMPLATE,
utils.context({'logout_msg': logout_msg})
)
class FederateAuth(View):
"""view to authenticated user agains a backend CAS then CAS_FEDERATE is True"""
@method_decorator(csrf_exempt)
def dispatch(self, request, *args, **kwargs):
"""dispatch different http request to the methods of the same name"""
return super(FederateAuth, self).dispatch(request, *args, **kwargs)
@staticmethod
def get_cas_client(request, provider):
"""return a CAS client object matching provider"""
service_url = utils.get_current_url(request, {"ticket", "provider"})
return CASFederateValidateUser(provider, service_url)
def post(self, request, provider=None):
"""method called on POST request"""
if not settings.CAS_FEDERATE:
return redirect("cas_server:login")
# POST with a provider, this is probably an SLO request
try:
provider = FederatedIendityProvider.objects.get(suffix=provider)
auth = self.get_cas_client(request, provider)
try:
auth.clean_sessions(request.POST['logoutRequest'])
except (KeyError, AttributeError):
pass
return HttpResponse("ok")
# else, a User is trying to log in using an identity provider
except FederatedIendityProvider.DoesNotExist:
# Manually checking for csrf to protect the code below
reason = CsrfViewMiddleware().process_view(request, None, (), {})
if reason is not None: # pragma: no cover (csrf checks are disabled during tests)
return reason # Failed the test, stop here.
form = forms.FederateSelect(request.POST)
if form.is_valid():
params = utils.copy_params(
request.POST,
ignore={"provider", "csrfmiddlewaretoken", "ticket"}
)
url = utils.reverse_params(
"cas_server:federateAuth",
kwargs=dict(provider=form.cleaned_data["provider"].suffix),
params=params
)
response = HttpResponseRedirect(url)
if form.cleaned_data["remember"]:
max_age = settings.CAS_FEDERATE_REMEMBER_TIMEOUT
utils.set_cookie(
response,
"_remember_provider",
form.cleaned_data["provider"].suffix,
max_age
)
return response
else:
return redirect("cas_server:login")
def get(self, request, provider=None):
"""method called on GET request"""
if not settings.CAS_FEDERATE:
return redirect("cas_server:login")
try:
provider = FederatedIendityProvider.objects.get(suffix=provider)
auth = self.get_cas_client(request, provider)
if 'ticket' not in request.GET:
return HttpResponseRedirect(auth.get_login_url())
else:
ticket = request.GET['ticket']
if auth.verify_ticket(ticket):
params = utils.copy_params(request.GET, ignore={"ticket"})
request.session["federate_username"] = auth.federated_username
request.session["federate_ticket"] = ticket
auth.register_slo(auth.federated_username, request.session.session_key, ticket)
url = utils.reverse_params("cas_server:login", params)
return HttpResponseRedirect(url)
else:
return HttpResponseRedirect(auth.get_login_url())
except FederatedIendityProvider.DoesNotExist:
return redirect("cas_server:login")
class LoginView(View, LogoutMixin):
"""credential requestor / acceptor"""
# pylint: disable=too-many-instance-attributes
# Nine is reasonable in this case.
user = None
form = None
request = None
service = None
renew = None
gateway = None
method = None
ajax = None
renewed = False
warned = False
# used if CAS_FEDERATE is True
username = None
ticket = None
INVALID_LOGIN_TICKET = 1
USER_LOGIN_OK = 2
USER_LOGIN_FAILURE = 3
USER_ALREADY_LOGGED = 4
USER_AUTHENTICATED = 5
USER_NOT_AUTHENTICATED = 6
def init_post(self, request):
"""Initialize POST received parameters"""
self.request = request
self.service = request.POST.get('service')
self.renew = bool(request.POST.get('renew') and request.POST['renew'] != "False")
self.gateway = request.POST.get('gateway')
self.method = request.POST.get('method')
self.ajax = settings.CAS_ENABLE_AJAX_AUTH and 'HTTP_X_AJAX' in request.META
if request.POST.get('warned') and request.POST['warned'] != "False":
self.warned = True
self.warn = request.POST.get('warn')
if settings.CAS_FEDERATE:
self.username = request.POST.get('username')
self.ticket = request.POST.get('ticket')
def gen_lt(self):
"""Generate a new LoginTicket and add it to the list of valid LT for the user"""
self.request.session['lt'] = self.request.session.get('lt', []) + [utils.gen_lt()]
if len(self.request.session['lt']) > 100:
self.request.session['lt'] = self.request.session['lt'][-100:]
def check_lt(self):
"""Check is the POSTed LoginTicket is valid, if yes invalide it"""
# save LT for later check
lt_valid = self.request.session.get('lt', [])
lt_send = self.request.POST.get('lt')
# generate a new LT (by posting the LT has been consumed)
self.gen_lt()
# check if send LT is valid
if lt_valid is None or lt_send not in lt_valid:
return False
else:
self.request.session['lt'].remove(lt_send)
self.request.session['lt'] = self.request.session['lt']
return True
def post(self, request, *args, **kwargs):
"""methode called on POST request on this view"""
self.init_post(request)
ret = self.process_post()
if ret == self.INVALID_LOGIN_TICKET:
messages.add_message(
self.request,
messages.ERROR,
_(u"Invalid login ticket")
)
elif ret == self.USER_LOGIN_OK:
self.user = models.User.objects.get_or_create(
username=self.request.session['username'],
session_key=self.request.session.session_key
)[0]
self.user.save()
elif ret == self.USER_LOGIN_FAILURE: # bad user login
if settings.CAS_FEDERATE:
self.ticket = None
self.username = None
self.init_form()
self.logout()
elif ret == self.USER_ALREADY_LOGGED:
pass
else:
raise EnvironmentError("invalid output for LoginView.process_post") # pragma: no cover
return self.common()
def process_post(self):
"""
Analyse the POST request:
* check that the LoginTicket is valid
* check that the user sumited credentials are valid
"""
if not self.check_lt():
values = self.request.POST.copy()
# if not set a new LT and fail
values['lt'] = self.request.session['lt'][-1]
self.init_form(values)
logger.warning("Receive an invalid login ticket")
return self.INVALID_LOGIN_TICKET
elif not self.request.session.get("authenticated") or self.renew:
self.init_form(self.request.POST)
if self.form.is_valid():
self.request.session.set_expiry(0)
self.request.session["username"] = self.form.cleaned_data['username']
self.request.session["warn"] = True if self.form.cleaned_data.get("warn") else False
self.request.session["authenticated"] = True
self.renewed = True
self.warned = True
logger.info("User %s successfully authenticated" % self.request.session["username"])
return self.USER_LOGIN_OK
else:
logger.warning("A logging attemps failed")
return self.USER_LOGIN_FAILURE
else:
logger.warning("Receuve a logging attempt whereas the user is already logged")
return self.USER_ALREADY_LOGGED
def init_get(self, request):
"""Initialize GET received parameters"""
self.request = request
self.service = request.GET.get('service')
self.renew = bool(request.GET.get('renew') and request.GET['renew'] != "False")
self.gateway = request.GET.get('gateway')
self.method = request.GET.get('method')
self.ajax = settings.CAS_ENABLE_AJAX_AUTH and 'HTTP_X_AJAX' in request.META
self.warn = request.GET.get('warn')
if settings.CAS_FEDERATE:
self.username = request.session.get("federate_username")
self.ticket = request.session.get("federate_ticket")
if self.username:
del request.session["federate_username"]
if self.ticket:
del request.session["federate_ticket"]
def get(self, request, *args, **kwargs):
"""methode called on GET request on this view"""
self.init_get(request)
self.process_get()
return self.common()
def process_get(self):
"""Analyse the GET request"""
# generate a new LT
self.gen_lt()
if not self.request.session.get("authenticated") or self.renew:
self.init_form()
return self.USER_NOT_AUTHENTICATED
return self.USER_AUTHENTICATED
def init_form(self, values=None):
"""Initialization of the good form depending of POST and GET parameters"""
form_initial = {
'service': self.service,
'method': self.method,
'warn': self.warn or self.request.session.get("warn"),
'lt': self.request.session['lt'][-1],
'renew': self.renew
}
if settings.CAS_FEDERATE:
if self.username and self.ticket:
form_initial['username'] = self.username
form_initial['password'] = self.ticket
form_initial['ticket'] = self.ticket
self.form = forms.FederateUserCredential(
values,
initial=form_initial
)
else:
self.form = forms.FederateSelect(values, initial=form_initial)
else:
self.form = forms.UserCredential(
values,
initial=form_initial
)
def service_login(self):
"""Perform login agains a service"""
try:
# is the service allowed
service_pattern = ServicePattern.validate(self.service)
# is the current user allowed on this service
service_pattern.check_user(self.user)
# if the user has asked to be warned before any login to a service
if self.request.session.get("warn", True) and not self.warned:
messages.add_message(
self.request,
messages.WARNING,
_(u"Authentication has been required by service %(name)s (%(url)s)") %
{'name': service_pattern.name, 'url': self.service}
)
if self.ajax:
data = {"status": "error", "detail": "confirmation needed"}
return json_response(self.request, data)
else:
warn_form = forms.WarnForm(initial={
'service': self.service,
'renew': self.renew,
'gateway': self.gateway,
'method': self.method,
'warned': True,
'lt': self.request.session['lt'][-1]
})
return render(
self.request,
settings.CAS_WARN_TEMPLATE,
utils.context({'form': warn_form})
)
else:
# redirect, using method ?
list(messages.get_messages(self.request)) # clean messages before leaving django
redirect_url = self.user.get_service_url(
self.service,
service_pattern,
renew=self.renewed
)
if not self.ajax:
return HttpResponseRedirect(redirect_url)
else:
data = {"status": "success", "detail": "auth", "url": redirect_url}
return json_response(self.request, data)
except ServicePattern.DoesNotExist:
error = 1
messages.add_message(
self.request,
messages.ERROR,
_(u'Service %(url)s non allowed.') % {'url': self.service}
)
except models.BadUsername:
error = 2
messages.add_message(
self.request,
messages.ERROR,
_(u"Username non allowed")
)
except models.BadFilter:
error = 3
messages.add_message(
self.request,
messages.ERROR,
_(u"User charateristics non allowed")
)
except models.UserFieldNotDefined:
error = 4
messages.add_message(
self.request,
messages.ERROR,
_(u"The attribut %(field)s is needed to use"
u" that service") % {'field': service_pattern.user_field}
)
# if gateway is set and auth failed redirect to the service without authentication
if self.gateway and not self.ajax:
list(messages.get_messages(self.request)) # clean messages before leaving django
return HttpResponseRedirect(self.service)
if not self.ajax:
return render(
self.request,
settings.CAS_LOGGED_TEMPLATE,
utils.context({'session': self.request.session})
)
else:
data = {"status": "error", "detail": "auth", "code": error}
return json_response(self.request, data)
def authenticated(self):
"""Processing authenticated users"""
try:
self.user = models.User.objects.get(
username=self.request.session.get("username"),
session_key=self.request.session.session_key
)
except models.User.DoesNotExist:
logger.warning(
"User %s seems authenticated but is not found in the database." % (
self.request.session.get("username"),
)
)
self.logout()
if self.ajax:
data = {
"status": "error",
"detail": "login required",
"url": utils.reverse_params("cas_server:login", params=self.request.GET)
}
return json_response(self.request, data)
else:
return utils.redirect_params("cas_server:login", params=self.request.GET)
# if login agains a service is self.requestest
if self.service:
return self.service_login()
else:
if self.ajax:
data = {"status": "success", "detail": "logged"}
return json_response(self.request, data)
else:
return render(
self.request,
settings.CAS_LOGGED_TEMPLATE,
utils.context({'session': self.request.session})
)
def not_authenticated(self):
"""Processing non authenticated users"""
if self.service:
try:
service_pattern = ServicePattern.validate(self.service)
if self.gateway and not self.ajax:
# clean messages before leaving django
list(messages.get_messages(self.request))
return HttpResponseRedirect(self.service)
if self.request.session.get("authenticated") and self.renew:
messages.add_message(
self.request,
messages.WARNING,
_(u"Authentication renewal required by service %(name)s (%(url)s).") %
{'name': service_pattern.name, 'url': self.service}
)
else:
messages.add_message(
self.request,
messages.WARNING,
_(u"Authentication required by service %(name)s (%(url)s).") %
{'name': service_pattern.name, 'url': self.service}
)
except ServicePattern.DoesNotExist:
messages.add_message(
self.request,
messages.ERROR,
_(u'Service %s non allowed') % self.service
)
if self.ajax:
data = {
"status": "error",
"detail": "login required",
"url": utils.reverse_params("cas_server:login", params=self.request.GET)
}
return json_response(self.request, data)
else:
if settings.CAS_FEDERATE:
if self.username and self.ticket:
return render(
self.request,
settings.CAS_LOGIN_TEMPLATE,
utils.context({
'form': self.form,
'auto_submit': True,
'post_url': reverse("cas_server:login")
})
)
else:
if (
self.request.COOKIES.get('_remember_provider') and
FederatedIendityProvider.objects.filter(
suffix=self.request.COOKIES['_remember_provider']
)
):
params = utils.copy_params(self.request.GET)
url = utils.reverse_params(
"cas_server:federateAuth",
params=params,
kwargs=dict(provider=self.request.COOKIES['_remember_provider'])
)
return HttpResponseRedirect(url)
else:
return render(
self.request,
settings.CAS_LOGIN_TEMPLATE,
utils.context({
'form': self.form,
'post_url': reverse("cas_server:federateAuth")
})
)
else:
return render(
self.request,
settings.CAS_LOGIN_TEMPLATE,
utils.context({'form': self.form})
)
def common(self):
"""Part execute uppon GET and POST request"""
# if authenticated and successfully renewed authentication if needed
if self.request.session.get("authenticated") and (not self.renew or self.renewed):
return self.authenticated()
else:
return self.not_authenticated()
class Auth(View):
"""A simple view to validate username/password/service tuple"""
@method_decorator(csrf_exempt)
def dispatch(self, request, *args, **kwargs):
"""dispatch requests based on method GET, POST, ..."""
return super(Auth, self).dispatch(request, *args, **kwargs)
@staticmethod
def post(request):
"""methode called on GET request on this view"""
username = request.POST.get('username')
password = request.POST.get('password')
service = request.POST.get('service')
secret = request.POST.get('secret')
if not settings.CAS_AUTH_SHARED_SECRET:
return HttpResponse(
"no\nplease set CAS_AUTH_SHARED_SECRET",
content_type="text/plain; charset=utf-8"
)
if secret != settings.CAS_AUTH_SHARED_SECRET:
return HttpResponse(u"no\n", content_type="text/plain; charset=utf-8")
if not username or not password or not service:
return HttpResponse(u"no\n", content_type="text/plain; charset=utf-8")
form = forms.UserCredential(
request.POST,
initial={
'service': service,
'method': 'POST',
'warn': False
}
)
if form.is_valid():
try:
user = models.User.objects.get_or_create(
username=form.cleaned_data['username'],
session_key=request.session.session_key
)[0]
user.save()
# is the service allowed
service_pattern = ServicePattern.validate(service)
# is the current user allowed on this service
service_pattern.check_user(user)
if not request.session.get("authenticated"):
user.delete()
return HttpResponse(u"yes\n", content_type="text/plain; charset=utf-8")
except (ServicePattern.DoesNotExist, models.ServicePatternException):
return HttpResponse(u"no\n", content_type="text/plain; charset=utf-8")
else:
return HttpResponse(u"no\n", content_type="text/plain; charset=utf-8")
class Validate(View):
"""service ticket validation"""
@staticmethod
def get(request):
"""methode called on GET request on this view"""
service = request.GET.get('service')
ticket = request.GET.get('ticket')
renew = True if request.GET.get('renew') else False
if service and ticket:
try:
ticket = ServiceTicket.objects.get(
value=ticket,
service=service,
validate=False,
renew=renew,
creation__gt=(timezone.now() - timedelta(seconds=ServiceTicket.VALIDITY))
)
ticket.validate = True
ticket.save()
logger.info(
"Validate: Service ticket %s validated, user %s authenticated on service %s" % (
ticket.value,
ticket.user.username,
ticket.service
)
)
if (ticket.service_pattern.user_field and
ticket.user.attributs.get(ticket.service_pattern.user_field)):
username = ticket.user.attributs.get(
ticket.service_pattern.user_field
)
if isinstance(username, list):
# the list is not empty because we wont generate a ticket with a user_field
# that evaluate to False
username = username[0]
else:
username = ticket.user.username
return HttpResponse(
u"yes\n%s\n" % username,
content_type="text/plain; charset=utf-8"
)
except ServiceTicket.DoesNotExist:
logger.warning(
(
"Validate: Service ticket %s not found or "
"already validated, auth to %s failed"
) % (
ticket,
service
)
)
return HttpResponse(u"no\n", content_type="text/plain; charset=utf-8")
else:
logger.warning("Validate: service or ticket missing")
return HttpResponse(u"no\n", content_type="text/plain; charset=utf-8")
@python_2_unicode_compatible
class ValidateError(Exception):
"""handle service validation error"""
def __init__(self, code, msg=""):
self.code = code
self.msg = msg
super(ValidateError, self).__init__(code)
def __str__(self):
return u"%s" % self.msg
def render(self, request):
"""render the error template for the exception"""
return render(
request,
"cas_server/serviceValidateError.xml",
{'code': self.code, 'msg': self.msg},
content_type="text/xml; charset=utf-8"
)
class ValidateService(View, AttributesMixin):
"""service ticket validation [CAS 2.0] and [CAS 3.0]"""
request = None
service = None
ticket = None
pgt_url = None
renew = None
allow_proxy_ticket = False
def get(self, request):
"""methode called on GET request on this view"""
self.request = request
self.service = request.GET.get('service')
self.ticket = request.GET.get('ticket')
self.pgt_url = request.GET.get('pgtUrl')
self.renew = True if request.GET.get('renew') else False
if not self.service or not self.ticket:
logger.warning("ValidateService: missing ticket or service")
return ValidateError(
u'INVALID_REQUEST',
u"you must specify a service and a ticket"
).render(request)
else:
try:
self.ticket, proxies = self.process_ticket()
params = {
'username': self.ticket.user.username,
'attributes': self.attributes(),
'proxies': proxies
}
if (self.ticket.service_pattern.user_field and
self.ticket.user.attributs.get(self.ticket.service_pattern.user_field)):
params['username'] = self.ticket.user.attributs.get(
self.ticket.service_pattern.user_field
)
if isinstance(params['username'], list):
# the list is not empty because we wont generate a ticket with a user_field
# that evaluate to False
params['username'] = params['username'][0]
if self.pgt_url and (
self.pgt_url.startswith("https://") or
re.match("^http://(127\.0\.0\.1|localhost)(:[0-9]+)?(/.*)?$", self.pgt_url)
):
return self.process_pgturl(params)
else:
logger.info(
"ValidateService: ticket %s validated for user %s on service %s." % (
self.ticket.value,
self.ticket.user.username,
self.ticket.service
)
)
logger.debug(
"ValidateService: User attributs are:\n%s" % (
pprint.pformat(self.ticket.attributs),
)
)
return render(
request,
"cas_server/serviceValidate.xml",
params,
content_type="text/xml; charset=utf-8"
)
except ValidateError as error:
logger.warning(
"ValidateService: validation error: %s %s" % (error.code, error.msg)
)
return error.render(request)
def process_ticket(self):
"""fetch the ticket angains the database and check its validity"""
try:
proxies = []
if self.ticket.startswith(ServiceTicket.PREFIX):
ticket = ServiceTicket.objects.get(
value=self.ticket,
validate=False,
renew=self.renew,
creation__gt=(timezone.now() - timedelta(seconds=ServiceTicket.VALIDITY))
)
elif self.allow_proxy_ticket and self.ticket.startswith(ProxyTicket.PREFIX):
ticket = ProxyTicket.objects.get(
value=self.ticket,
validate=False,
renew=self.renew,
creation__gt=(timezone.now() - timedelta(seconds=ProxyTicket.VALIDITY))
)
for prox in ticket.proxies.all():
proxies.append(prox.url)
else:
raise ValidateError(u'INVALID_TICKET', self.ticket)
ticket.validate = True
ticket.save()
if ticket.service != self.service:
raise ValidateError(u'INVALID_SERVICE', self.service)
return ticket, proxies
except (ServiceTicket.DoesNotExist, ProxyTicket.DoesNotExist):
raise ValidateError(u'INVALID_TICKET', 'ticket not found')
def process_pgturl(self, params):
"""Handle PGT request"""
try:
pattern = ServicePattern.validate(self.pgt_url)
if pattern.proxy_callback:
proxyid = utils.gen_pgtiou()
pticket = ProxyGrantingTicket.objects.create(
user=self.ticket.user,
service=self.pgt_url,
service_pattern=pattern,
single_log_out=pattern.single_log_out
)
url = utils.update_url(self.pgt_url, {'pgtIou': proxyid, 'pgtId': pticket.value})
try:
ret = requests.get(url, verify=settings.CAS_PROXY_CA_CERTIFICATE_PATH)
if ret.status_code == 200:
params['proxyGrantingTicket'] = proxyid
else:
pticket.delete()
logger.info(
(
"ValidateService: ticket %s validated for user %s on service %s. "
"Proxy Granting Ticket transmited to %s."
) % (
self.ticket.value,
self.ticket.user.username,
self.ticket.service,
self.pgt_url
)
)
logger.debug(
"ValidateService: User attributs are:\n%s" % (
pprint.pformat(self.ticket.attributs),
)
)
return render(
self.request,
"cas_server/serviceValidate.xml",
params,
content_type="text/xml; charset=utf-8"
)
except requests.exceptions.RequestException as error:
error = utils.unpack_nested_exception(error)
raise ValidateError(
u'INVALID_PROXY_CALLBACK',
u"%s: %s" % (type(error), str(error))
)
else:
raise ValidateError(
u'INVALID_PROXY_CALLBACK',
u"callback url not allowed by configuration"
)
except ServicePattern.DoesNotExist:
raise ValidateError(
u'INVALID_PROXY_CALLBACK',
u'callback url not allowed by configuration'
)
class Proxy(View):
"""proxy ticket service"""
request = None
pgt = None
target_service = None
def get(self, request):
"""methode called on GET request on this view"""
self.request = request
self.pgt = request.GET.get('pgt')
self.target_service = request.GET.get('targetService')
try:
if self.pgt and self.target_service:
return self.process_proxy()
else:
raise ValidateError(
u'INVALID_REQUEST',
u"you must specify and pgt and targetService"
)
except ValidateError as error:
logger.warning("Proxy: validation error: %s %s" % (error.code, error.msg))
return error.render(request)
def process_proxy(self):
"""handle PT request"""
try:
# is the target service allowed
pattern = ServicePattern.validate(self.target_service)
if not pattern.proxy:
raise ValidateError(
u'UNAUTHORIZED_SERVICE',
u'the service %s do not allow proxy ticket' % self.target_service
)
# is the proxy granting ticket valid
ticket = ProxyGrantingTicket.objects.get(
value=self.pgt,
creation__gt=(timezone.now() - timedelta(seconds=ProxyGrantingTicket.VALIDITY)),
validate=False
)
# is the pgt user allowed on the target service
pattern.check_user(ticket.user)
pticket = ticket.user.get_ticket(
ProxyTicket,
self.target_service,
pattern,
renew=False)
models.Proxy.objects.create(proxy_ticket=pticket, url=ticket.service)
logger.info(
"Proxy ticket created for user %s on service %s." % (
ticket.user.username,
self.target_service
)
)
return render(
self.request,
"cas_server/proxy.xml",
{'ticket': pticket.value},
content_type="text/xml; charset=utf-8"
)
except ProxyGrantingTicket.DoesNotExist:
raise ValidateError(u'INVALID_TICKET', u'PGT %s not found' % self.pgt)
except ServicePattern.DoesNotExist:
raise ValidateError(u'UNAUTHORIZED_SERVICE', self.target_service)
except (models.BadUsername, models.BadFilter, models.UserFieldNotDefined):
raise ValidateError(
u'UNAUTHORIZED_USER',
u'User %s not allowed on %s' % (ticket.user.username, self.target_service)
)
@python_2_unicode_compatible
class SamlValidateError(Exception):
"""handle saml validation error"""
def __init__(self, code, msg=""):
self.code = code
self.msg = msg
super(SamlValidateError, self).__init__(code)
def __str__(self):
return u"%s" % self.msg
def render(self, request):
"""render the error template for the exception"""
return render(
request,
"cas_server/samlValidateError.xml",
{
'code': self.code,
'msg': self.msg,
'IssueInstant': timezone.now().isoformat(),
'ResponseID': utils.gen_saml_id()
},
content_type="text/xml; charset=utf-8"
)
class SamlValidate(View, AttributesMixin):
"""SAML ticket validation"""
request = None
target = None
ticket = None
root = None
@method_decorator(csrf_exempt)
def dispatch(self, request, *args, **kwargs):
"""dispatch requests based on method GET, POST, ..."""
return super(SamlValidate, self).dispatch(request, *args, **kwargs)
def post(self, request):
"""methode called on POST request on this view"""
self.request = request
self.target = request.GET.get('TARGET')
self.root = etree.fromstring(request.body)
try:
self.ticket = self.process_ticket()
expire_instant = (self.ticket.creation +
timedelta(seconds=self.ticket.VALIDITY)).isoformat()
attributes = self.attributes()
params = {
'IssueInstant': timezone.now().isoformat(),
'expireInstant': expire_instant,
'Recipient': self.target,
'ResponseID': utils.gen_saml_id(),
'username': self.ticket.user.username,
'attributes': attributes
}
if (self.ticket.service_pattern.user_field and
self.ticket.user.attributs.get(self.ticket.service_pattern.user_field)):
params['username'] = self.ticket.user.attributs.get(
self.ticket.service_pattern.user_field
)
if isinstance(params['username'], list):
# the list is not empty because we wont generate a ticket with a user_field
# that evaluate to False
params['username'] = params['username'][0]
logger.info(
"SamlValidate: ticket %s validated for user %s on service %s." % (
self.ticket.value,
self.ticket.user.username,
self.ticket.service
)
)
logger.debug(
"SamlValidate: User attributs are:\n%s" % pprint.pformat(self.ticket.attributs)
)
return render(
request,
"cas_server/samlValidate.xml",
params,
content_type="text/xml; charset=utf-8"
)
except SamlValidateError as error:
logger.warning("SamlValidate: validation error: %s %s" % (error.code, error.msg))
return error.render(request)
def process_ticket(self):
"""validate ticket from SAML XML body"""
try:
auth_req = self.root.getchildren()[1].getchildren()[0]
ticket = auth_req.getchildren()[0].text
if ticket.startswith(ServiceTicket.PREFIX):
ticket = ServiceTicket.objects.get(
value=ticket,
validate=False,
creation__gt=(timezone.now() - timedelta(seconds=ServiceTicket.VALIDITY))
)
elif ticket.startswith(ProxyTicket.PREFIX):
ticket = ProxyTicket.objects.get(
value=ticket,
validate=False,
creation__gt=(timezone.now() - timedelta(seconds=ProxyTicket.VALIDITY))
)
else:
raise SamlValidateError(
u'AuthnFailed',
u'ticket %s should begin with PT- or ST-' % ticket
)
ticket.validate = True
ticket.save()
if ticket.service != self.target:
raise SamlValidateError(
u'AuthnFailed',
u'TARGET %s do not match ticket service' % self.target
)
return ticket
except (IndexError, KeyError):
raise SamlValidateError(u'VersionMismatch')
except (ServiceTicket.DoesNotExist, ProxyTicket.DoesNotExist):
raise SamlValidateError(u'AuthnFailed', u'ticket %s not found' % ticket)