cas_provider/views.py

   1 from django.conf import settings
   2 from django.contrib.auth import login as auth_login, logout as auth_logout
   3 from django.core.urlresolvers import get_callable
   4 from django.http import HttpResponse, HttpResponseRedirect
   5 from django.shortcuts import render_to_response
   6 from django.template import RequestContext
   7 from forms import LoginForm
   8 from models import ServiceTicket, LoginTicket
   9
  10
  11 __all__ = ['login', 'validate', 'logout', 'service_validate']
  12
  13
  14 INVALID_TICKET = 'INVALID_TICKET'
  15 INVALID_SERVICE = 'INVALID_SERVICE'
  16 INVALID_REQUEST = 'INVALID_REQUEST'
  17 INTERNAL_ERROR = 'INTERNAL_ERROR'
  18
  19 ERROR_MESSAGES = (
  20     (INVALID_TICKET, u'The provided ticket is invalid.'),
  21     (INVALID_SERVICE, u'Service is invalid'),
  22     (INVALID_REQUEST, u'Not all required parameters were sent.'),
  23     (INTERNAL_ERROR, u'An internal error occurred during ticket validation'),
  24 )
  25
  26
  27 def login(request, template_name='cas/login.html', \
  28                 success_redirect=settings.LOGIN_REDIRECT_URL,
  29                 warn_template_name='cas/warn.html',
  30                 form_class=LoginForm):
  31     service = request.GET.get('service', None)
  32     if request.user.is_authenticated():
  33         if service is not None:
  34             if request.GET.get('warn', False):
  35                 return render_to_response(warn_template_name, {
  36                     'service': service,
  37                     'warn': False
  38                 }, context_instance=RequestContext(request))
  39             ticket = ServiceTicket.objects.create(service=service, user=request.user)
  40             return HttpResponseRedirect(ticket.get_redirect_url())
  41         else:
  42             return HttpResponseRedirect(success_redirect)
  43     if request.method == 'POST':
  44         form = form_class(data=request.POST, request=request)
  45         if form.is_valid():
  46             user = form.get_user()
  47             auth_login(request, user)
  48             service = form.cleaned_data.get('service')
  49             if service is not None:
  50                 ticket = ServiceTicket.objects.create(service=service, user=user)
  51                 success_redirect = ticket.get_redirect_url()
  52             return HttpResponseRedirect(success_redirect)
  53     else:
  54         form = form_class(request=request, initial={
  55             'service': service,
  56             'lt': LoginTicket.objects.create()
  57         })
  58     if hasattr(request, 'session') and hasattr(request.session, 'set_test_cookie'):
  59         request.session.set_test_cookie()
  60     return render_to_response(template_name, {
  61         'form': form,
  62         'errors': form.get_errors() if hasattr(form, 'get_errors') else None,
  63     }, context_instance=RequestContext(request))
  64
  65
  66 def validate(request):
  67     """Validate ticket via CAS v.1 protocol"""
  68     service = request.GET.get('service', None)
  69     ticket_string = request.GET.get('ticket', None)
  70     if service is not None and ticket_string is not None:
  71         #renew = request.GET.get('renew', True)
  72         #if not renew:
  73         # TODO: check user SSO session
  74         try:
  75             ticket = ServiceTicket.objects.get(ticket=ticket_string)
  76             assert ticket.service == service
  77             username = ticket.user.username
  78             ticket.delete()
  79             return HttpResponse("yes\n%s\n" % username)
  80         except:
  81             pass
  82     return HttpResponse("no\n\n")
  83
  84
  85 def logout(request, template_name='cas/logout.html', \
  86                 auto_redirect=settings.CAS_AUTO_REDIRECT_AFTER_LOGOUT):
  87     url = request.GET.get('url', None)
  88     if request.user.is_authenticated():
  89         auth_logout(request)
  90         if url and auto_redirect:
  91             return HttpResponseRedirect(url)
  92     return render_to_response(template_name, {'url': url}, \
  93                               context_instance=RequestContext(request))
  94
  95
  96 def service_validate(request):
  97     """Validate ticket via CAS v.2 protocol"""
  98     service = request.GET.get('service', None)
  99     ticket_string = request.GET.get('ticket', None)
 100     if service is None or ticket_string is None:
 101         return _cas2_error_response(INVALID_REQUEST)
 102
 103     try:
 104         ticket = ServiceTicket.objects.get(ticket=ticket_string)
 105     except ServiceTicket.DoesNotExist:
 106         return _cas2_error_response(INVALID_TICKET)
 107
 108     if ticket.service != service:
 109         ticket.delete()
 110         return _cas2_error_response(INVALID_SERVICE)
 111
 112     user = ticket.user
 113     ticket.delete()
 114     return _cas2_sucess_response(user)
 115
 116
 117 def _cas2_error_response(code):
 118     return HttpResponse(u''''<cas:serviceResponse xmlns:cas="http://www.yale.edu/tp/cas">
 119             <cas:authenticationFailure code="%(code)s">
 120                 %(message)s
 121             </cas:authenticationFailure>
 122         </cas:serviceResponse>''' % {
 123             'code': code,
 124             'message': dict(ERROR_MESSAGES).get(code)
 125     }, mimetype='text/xml')
 126
 127
 128 def _cas2_sucess_response(user):
 129     return HttpResponse(auth_success_response(user), mimetype='text/xml')
 130
 131
 132 def auth_success_response(user):
 133     from attribute_formatters import CAS, NSMAP, etree
 134
 135     response = etree.Element(CAS + 'serviceResponse', nsmap=NSMAP)
 136     auth_success = etree.SubElement(response, CAS + 'authenticationSuccess')
 137     username = etree.SubElement(auth_success, CAS + 'user')
 138     username.text = user.username
 139
 140     if settings.CAS_CUSTOM_ATTRIBUTES_CALLBACK:
 141         callback = get_callable(settings.CAS_CUSTOM_ATTRIBUTES_CALLBACK)
 142         attrs = callback(user)
 143         if len(attrs) > 0:
 144             formater = get_callable(settings.CAS_CUSTOM_ATTRIBUTES_FORMATER)
 145             formater(auth_success, attrs)
 146     return unicode(etree.tostring(response, encoding='utf-8'), 'utf-8')