Compatibility up to Django 2.1, dropped < 1.8. Removed unused code, fixed tests.
[django-cas-provider.git] / cas_provider / views.py
index dcc0bbd..ccf84a2 100644 (file)
-import urllib
+from __future__ import unicode_literals
+
+import logging
+logger = logging.getLogger('cas_provider.views')
+
+try:
+    from urllib.error import HTTPError, URLError
+    from urllib.parse import parse_qsl, urlencode, urlparse, urlsplit, urlunsplit
+    from urllib.request import urlopen
+except ImportError:
+    from urllib import urlencode
+    from urllib2 import HTTPError, URLError, urlopen
+    from urlparse import parse_qsl, urlparse, urlsplit, urlunsplit
+from functools import wraps
+
+from django import VERSION
+from django.utils.decorators import available_attrs
+from django.views.decorators.debug import sensitive_post_parameters
+from django.views.decorators.cache import cache_control
+from django.utils.cache import patch_cache_control
+from django.views.decorators.csrf import csrf_protect
 
 from django.http import HttpResponse, HttpResponseRedirect
 
 from django.http import HttpResponse, HttpResponseRedirect
-from django.shortcuts import render_to_response
+from django.conf import settings
+from django.contrib.auth import login as auth_login, logout as auth_logout
+
+from django.shortcuts import render
+from django.utils.translation import ugettext as _
 from django.template import RequestContext
 from django.contrib.auth import authenticate
 from django.template import RequestContext
 from django.contrib.auth import authenticate
-from django.contrib.auth import login as auth_login, logout as auth_logout
-from django.core.urlresolvers import reverse
+from django.utils.translation import ugettext as _
+
+from lxml import etree
+from cas_provider.attribute_formatters import NSMAP, CAS
+from cas_provider.models import ProxyGrantingTicket, ProxyTicket
+from cas_provider.models import ServiceTicket
+
+from cas_provider.forms import LoginForm, MergeLoginForm
+
+from . import signals
+
+if VERSION >= (1, 10):
+    from django.urls import get_callable, reverse
+    user_is_authenticated = lambda user: user.is_authenticated
+else:
+    from django.core.urlresolvers import get_callable, reverse
+    user_is_authenticated = lambda user: user.is_authenticated()
+
+__all__ = ['login', 'validate', 'logout', 'service_validate']
+
+INVALID_TICKET = 'INVALID_TICKET'
+INVALID_SERVICE = 'INVALID_SERVICE'
+INVALID_REQUEST = 'INVALID_REQUEST'
+INTERNAL_ERROR = 'INTERNAL_ERROR'
+
+ERROR_MESSAGES = (
+    (INVALID_TICKET, 'The provided ticket is invalid.'),
+    (INVALID_SERVICE, 'Service is invalid'),
+    (INVALID_REQUEST, 'Not all required parameters were sent.'),
+    (INTERNAL_ERROR, 'An internal error occurred during ticket validation'),
+    )
 
 
-from forms import LoginForm, MergeLoginForm
-from models import ServiceTicket
-from utils import create_service_ticket
-from exceptions import SameEmailMismatchedPasswords
 
 
-__all__ = ['login', 'validate', 'logout']
+logger = logging.getLogger(__name__)
 
 
 
 
-def login(request, template_name='cas/login.html', success_redirect='/account/', merge=False):
+_never_cache = cache_control(no_cache=True, must_revalidate=True)
+
+
+def never_cache(view_func):
+    """
+    Decorator that adds headers to a response so that it will
+    never be cached.
+    """
+    @wraps(view_func, assigned=available_attrs(view_func))
+    def _wrapped_view_func(request, *args, **kwargs):
+        response = view_func(request, *args, **kwargs)
+        patch_cache_control(response, no_cache=True,
+                            must_revalidate=True, proxy_revalidate=True)
+        response['Pragma'] = 'no-cache'
+        return response
+    return _wrapped_view_func
+
+
+@sensitive_post_parameters()
+@csrf_protect
+@never_cache
+def login(request, template_name='cas/login.html',
+          success_redirect=settings.LOGIN_REDIRECT_URL,
+          warn_template_name='cas/warn.html', **kwargs):
+    merge = kwargs.get('merge', False)
+    logging.debug('CAS Provider Login view. Method is %s, merge is %s, template is %s.',
+                  request.method, merge, template_name)
+
     service = request.GET.get('service', None)
     if service is not None:
     service = request.GET.get('service', None)
     if service is not None:
+        # Save the service on the session, for later use if we end up
+        # in one of the more complicated workflows.
         request.session['service'] = service
         request.session['service'] = service
-    if request.user.is_authenticated():
-        if service is not None:
-            ticket = create_service_ticket(request.user, service)
-            if service.find('?') == -1:
-                return HttpResponseRedirect(service + '?ticket=' + ticket.ticket)
-            else:
-                return HttpResponseRedirect(service + '&ticket=' + ticket.ticket)
-        else:
-            return HttpResponseRedirect(success_redirect)
+
+    user = request.user
+
     errors = []
     errors = []
+
     if request.method == 'POST':
         if merge:
             form = MergeLoginForm(request.POST, request=request)
     if request.method == 'POST':
         if merge:
             form = MergeLoginForm(request.POST, request=request)
@@ -36,8 +109,9 @@ def login(request, template_name='cas/login.html', success_redirect='/account/',
             form = LoginForm(request.POST, request=request)
 
         if form.is_valid():
             form = LoginForm(request.POST, request=request)
 
         if form.is_valid():
+            service = form.cleaned_data.get('service', None)
             try:
             try:
-                auth_args = dict(username=form.cleaned_data['email'],
+                auth_args = dict(username=form.cleaned_data['username'],
                                  password=form.cleaned_data['password'])
                 if merge:
                     # We only want to send the merge argument if it's
                                  password=form.cleaned_data['password'])
                 if merge:
                     # We only want to send the merge argument if it's
@@ -45,7 +119,7 @@ def login(request, template_name='cas/login.html', success_redirect='/account/',
                     # through the auth backends properly.
                     auth_args['merge'] = merge
                 user = authenticate(**auth_args)
                     # through the auth backends properly.
                     auth_args['merge'] = merge
                 user = authenticate(**auth_args)
-            except SameEmailMismatchedPasswords:
+            except:
                 # Need to merge the accounts?
                 if merge:
                     # We shouldn't get here...
                 # Need to merge the accounts?
                 if merge:
                     # We shouldn't get here...
@@ -54,76 +128,284 @@ def login(request, template_name='cas/login.html', success_redirect='/account/',
                     base_url = reverse('cas_provider_merge')
                     args = dict(
                         success_redirect=success_redirect,
                     base_url = reverse('cas_provider_merge')
                     args = dict(
                         success_redirect=success_redirect,
-                        email=form.cleaned_data['email'],
+                        username=form.cleaned_data['username'],
                         )
                     if service is not None:
                         args['service'] = service
                         )
                     if service is not None:
                         args['service'] = service
-                    args = urllib.urlencode(args)
+                    args = urlencode(args)
 
 
-                    return HttpResponseRedirect('%s?%s' % (base_url, args))
-            
-            if user is not None:
+                    url = '%s?%s' % (base_url, args)
+                    logging.debug('Redirecting to %s', url)
+                    return HttpResponseRedirect(url)
+
+            if user is None:
+                errors.append(_('Incorrect username and/or password.'))
+            else:
                 if user.is_active:
                     auth_login(request, user)
                 if user.is_active:
                     auth_login(request, user)
-                    if service is not None:
-                        ticket = create_service_ticket(user, service)
-                        return HttpResponseRedirect(service + '?ticket=' + ticket.ticket)
-                    else:
-                        return HttpResponseRedirect(success_redirect)
-                else:
-                    errors.append('This account is disabled.')
-            else:
-                    errors.append('Incorrect username and/or password.')
-    else:
+
+    else:  # Not a POST...
         if merge:
         if merge:
-            form = MergeLoginForm(initial={'service': service, 'email': request.GET.get('email')})
+            form = MergeLoginForm(initial={'service': service, 'username': request.GET.get('username')})
         else:
             form = LoginForm(initial={'service': service})
         else:
             form = LoginForm(initial={'service': service})
-    return render_to_response(template_name, {'form': form, 'errors': errors}, context_instance=RequestContext(request))
 
 
+    if user is not None and user_is_authenticated(user):
+        # We have an authenticated user.
+        if not user.is_active:
+            errors.append(_('This account is disabled. Please contact us if you feel it should be enabled again.'))
+        else:
+            # Send the on_cas_login signal. If we get an HttpResponse, return that.
+            for receiver, response in signals.on_cas_login.send(sender=login, request=request, **kwargs):
+                if isinstance(response, HttpResponse):
+                    return response
 
 
-def socialauth_login(request, template_name='cas/login.html', success_redirect='/account/'):
-    """ Similiar to login but user has been authenticated already through social auth.
-        This step authenticates the login and generates a service ticket.
-    """
-    user = request.user
-    user.backend = 'django.contrib.auth.backends.ModelBackend'
-    if request.session.has_key('service'):
-        service = request.session['service']
-        del request.session['service']
-    else:
-        service = '/'
-    errors = []
-    if user is not None:
-        if user.is_active:
-            auth_login(request, user)
-            if service is not None:
-                ticket = create_service_ticket(user, service)
-                return HttpResponseRedirect(service + '?ticket=' + ticket.ticket)
-            else:
+            if service is None:
+                # Try and pull the service off the session
+                service = request.session.pop('service', service)
+
+            signals.on_cas_login_success.send(sender=login, request=request,
+                                              service=service, **kwargs)
+
+            if service is None:
+                # Normal internal success redirection.
+                logging.debug('Redirecting to %s', success_redirect)
                 return HttpResponseRedirect(success_redirect)
                 return HttpResponseRedirect(success_redirect)
-        else:
-            errors.append('This account is disabled.')
-    else:
-            errors.append('Incorrect username and/or password.')
-    return render_to_response(template_name, {'errors': errors}, context_instance=RequestContext(request))
+            else:
+                if request.GET.get('warn', False):
+                    return render(request, warn_template_name, {
+                        'service': service,
+                        'warn': False
+                    })
+
+                # Create a service ticket and redirect to the service.
+                ticket = ServiceTicket.objects.create(service=service, user=user)
+                if 'service' in request.session:
+                    # Don't need this any more.
+                    del request.session['service']
 
 
+                url = ticket.get_redirect_url()
+                logging.debug('Redirecting to %s', url)
+                return HttpResponseRedirect(url)
 
 
+    logging.debug('Rendering response on %s, merge is %s', template_name, merge)
+    return render(request, template_name, {'form': form, 'errors': errors})
+
+
+@never_cache
 def validate(request):
 def validate(request):
+    """Validate ticket via CAS v.1 protocol
+    """
     service = request.GET.get('service', None)
     ticket_string = request.GET.get('ticket', None)
     service = request.GET.get('service', None)
     ticket_string = request.GET.get('ticket', None)
+    logger.info('Validating ticket %s for %s', ticket_string, service)
     if service is not None and ticket_string is not None:
     if service is not None and ticket_string is not None:
+        #renew = request.GET.get('renew', True)
+        #if not renew:
+        # TODO: check user SSO session
         try:
             ticket = ServiceTicket.objects.get(ticket=ticket_string)
         try:
             ticket = ServiceTicket.objects.get(ticket=ticket_string)
+            assert ticket.service == service
+        except ServiceTicket.DoesNotExist:
+            logger.exception("Tried to validate with an invalid ticket %s for %s", ticket_string, service)
+        except Exception as e:
+            logger.exception('Got an exception: %s', e)
+        else:
             username = ticket.user.username
             ticket.delete()
             username = ticket.user.username
             ticket.delete()
-            return HttpResponse("yes\n%s\n" % username)
-        except:
-            pass
+
+            results = signals.on_cas_collect_histories.send(sender=validate, for_user=ticket.user)
+            histories = '\n'.join('\n'.join(rs) for rc, rs in results)
+            logger.info('Validated %s %s', username, "(also %s)" % histories if histories else '')
+            return HttpResponse("yes\n%s\n%s" % (username, histories))
+
+    logger.info('Validation failed.')
     return HttpResponse("no\n\n")
     return HttpResponse("no\n\n")
-    
 
 
-def logout(request, template_name='cas/logout.html'):
+
+@never_cache
+def logout(request, template_name='cas/logout.html',
+           auto_redirect=settings.CAS_AUTO_REDIRECT_AFTER_LOGOUT):
     url = request.GET.get('url', None)
     url = request.GET.get('url', None)
-    auth_logout(request)
-    return render_to_response(template_name, {'url': url}, context_instance=RequestContext(request))
+    if user_is_authenticated(request.user):
+        for ticket in ServiceTicket.objects.filter(user=request.user):
+            ticket.delete()
+        auth_logout(request)
+        if url and auto_redirect:
+            return HttpResponseRedirect(url)
+    return render(request, template_name, {'url': url})
+
+
+@never_cache
+def proxy(request):
+    targetService = request.GET['targetService']
+    pgt_id = request.GET['pgt']
+
+    try:
+        proxyGrantingTicket = ProxyGrantingTicket.objects.get(ticket=pgt_id)
+    except ProxyGrantingTicket.DoesNotExist:
+        return _cas2_error_response(INVALID_TICKET)
+
+    pt = ProxyTicket.objects.create(proxyGrantingTicket=proxyGrantingTicket,
+        user=proxyGrantingTicket.user,
+        service=targetService)
+    return _cas2_proxy_success(pt.ticket)
+
+
+def ticket_validate(service, ticket_string, pgtUrl):
+    if service is None or ticket_string is None:
+        return _cas2_error_response(INVALID_REQUEST)
+
+    try:
+        if ticket_string.startswith('ST'):
+            ticket = ServiceTicket.objects.get(ticket=ticket_string)
+        elif ticket_string.startswith('PT'):
+            ticket = ProxyTicket.objects.get(ticket=ticket_string)
+        else:
+            return _cas2_error_response(INVALID_TICKET,
+                '%(ticket)s is neither Service (ST-...) nor Proxy Ticket (PT-...)' % {
+                    'ticket': ticket_string})
+    except ServiceTicket.DoesNotExist:
+        return _cas2_error_response(INVALID_TICKET)
+
+    ticketUrl = urlparse(ticket.service)
+    serviceUrl = urlparse(service)
+
+    if not(ticketUrl.hostname == serviceUrl.hostname and ticketUrl.path == serviceUrl.path and ticketUrl.port == serviceUrl.port):
+        return _cas2_error_response(INVALID_SERVICE)
+
+    pgtIouId = None
+    proxies = ()
+    if pgtUrl is not None:
+        pgt = generate_proxy_granting_ticket(pgtUrl, ticket)
+        if pgt:
+            pgtIouId = pgt.pgtiou
+
+    try:
+        proxyTicket = ticket.proxyticket
+    except ProxyTicket.DoesNotExist:
+        pass
+    else:
+        pgt = proxyTicket.proxyGrantingTicket
+        # I am issued by this proxy granting ticket
+        while pgt.pgt is not None:
+            proxies += (pgt.service,)
+            pgt = pgt.pgt
+
+    user = ticket.user
+    ticket.delete()
+    return _cas2_sucess_response(user, pgtIouId, proxies)
+
+
+@never_cache
+def service_validate(request):
+    """Validate ticket via CAS v.2 protocol"""
+    service = request.GET.get('service', None)
+    ticket_string = request.GET.get('ticket', None)
+    pgtUrl = request.GET.get('pgtUrl', None)
+    if ticket_string.startswith('PT-'):
+        return _cas2_error_response(INVALID_TICKET, "serviceValidate cannot verify proxy tickets")
+    else:
+        return ticket_validate(service, ticket_string, pgtUrl)
+
+
+@never_cache
+def proxy_validate(request):
+    """Validate ticket via CAS v.2 protocol"""
+    service = request.GET.get('service', None)
+    ticket_string = request.GET.get('ticket', None)
+    pgtUrl = request.GET.get('pgtUrl', None)
+    return ticket_validate(service, ticket_string, pgtUrl)
+
+
+def generate_proxy_granting_ticket(pgt_url, ticket):
+    proxy_callback_good_status = (200, 202, 301, 302, 304)
+    uri = list(urlsplit(pgt_url))
+
+    pgt = ProxyGrantingTicket()
+    pgt.user = ticket.user
+    pgt.service = ticket.service
+    # Remember if it's a chained PGT.
+    pgt.pgt = getattr(ticket, 'proxyGrantingTicket', None)
+
+    params = {'pgtId': pgt.ticket, 'pgtIou': pgt.pgtiou}
+
+    query = dict(parse_qsl(uri[4]))
+    query.update(params)
+
+    uri[3] = urlencode(query)
+
+    try:
+        urlopen(urlunsplit(uri))
+    except HTTPError as e:
+        if not e.code in proxy_callback_good_status:
+            logger.debug('Checking Proxy Callback URL {0} returned {1}. Not issuing PGT.'.format(uri, e.code))
+            return
+    except URLError as e:
+        logger.debug('Checking Proxy Callback URL {0} raised URLError. Not issuing PGT.'.format(uri))
+        return
+
+    pgt.save()
+    return pgt
+
+
+def _cas2_proxy_success(pt):
+    return HttpResponse(proxy_success(pt))
+
+
+def _cas2_sucess_response(user, pgt=None, proxies=None):
+    return HttpResponse(auth_success_response(user, pgt, proxies), content_type='text/xml')
+
+
+def _cas2_error_response(code, message=None):
+    return HttpResponse('''<cas:serviceResponse xmlns:cas="http://www.yale.edu/tp/cas">
+            <cas:authenticationFailure code="%(code)s">
+                %(message)s
+            </cas:authenticationFailure>
+        </cas:serviceResponse>''' % {
+        'code': code,
+        'message': message if message else dict(ERROR_MESSAGES).get(code)
+    }, content_type='text/xml')
+
+
+def proxy_success(pt):
+    response = etree.Element(CAS + 'serviceResponse', nsmap=NSMAP)
+    proxySuccess = etree.SubElement(response, CAS + 'proxySuccess')
+    proxyTicket = etree.SubElement(proxySuccess, CAS + 'proxyTicket')
+    proxyTicket.text = pt
+    return etree.tostring(response, encoding='unicode')
+
+
+def auth_success_response(user, pgt, proxies):
+    response = etree.Element(CAS + 'serviceResponse', nsmap=NSMAP)
+    auth_success = etree.SubElement(response, CAS + 'authenticationSuccess')
+    username = etree.SubElement(auth_success, CAS + 'user')
+    username.text = user.username
+
+    attrs = {}
+    for receiver, custom in signals.cas_collect_custom_attributes.send(sender=auth_success_response, user=user):
+        if custom:
+            attrs.update(custom)
+
+    identifiers = [i for sr, rr in signals.on_cas_collect_histories.send(sender=validate, for_user=user)
+                   for i in rr]
+
+    if identifiers:
+        # Singular `identifier`, as that is the name of the element tag(s).
+        attrs['identifier'] = identifiers
+
+    if attrs:
+        formatter = get_callable(settings.CAS_CUSTOM_ATTRIBUTES_FORMATER)
+        formatter(auth_success, attrs)
+
+    if pgt:
+        pgtElement = etree.SubElement(auth_success, CAS + 'proxyGrantingTicket')
+        pgtElement.text = pgt
+
+    if proxies:
+        proxiesElement = etree.SubElement(auth_success, CAS + "proxies")
+        for proxy in proxies:
+            proxyElement = etree.SubElement(proxiesElement, CAS + "proxy")
+            proxyElement.text = proxy
+
+    return etree.tostring(response, encoding='unicode')