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     service = request.GET.get('service', None)
  31     if request.user.is_authenticated():
  32         if service is not None:
  33             if request.GET.get('warn', False):
  34                 return render_to_response(warn_template_name, {
  35                     'service': service,
  36                     'warn': False
  37                 }, context_instance=RequestContext(request))
  38             ticket = ServiceTicket.objects.create(service=service, user=request.user)
  39             return HttpResponseRedirect(ticket.get_redirect_url())
  40         else:
  41             return HttpResponseRedirect(success_redirect)
  42     if request.method == 'POST':
  43         form = LoginForm(request.POST)
  44         if form.is_valid():
  45             user = form.get_user()
  46             auth_login(request, user)
  47             service = form.cleaned_data.get('service')
  48             if service is not None:
  49                 ticket = ServiceTicket.objects.create(service=service, user=user)
  50                 success_redirect = ticket.get_redirect_url()
  51             return HttpResponseRedirect(success_redirect)
  52     else:
  53         form = LoginForm(initial={
  54             'service': service,
  55             'lt': LoginTicket.objects.create()
  56         })
  57     return render_to_response(template_name, {
  58         'form': form,
  59         'errors': form.get_errors()
  60     }, context_instance=RequestContext(request))
  61
  62
  63 def validate(request):
  64     """Validate ticket via CAS v.1 protocol"""
  65     service = request.GET.get('service', None)
  66     ticket_string = request.GET.get('ticket', None)
  67     if service is not None and ticket_string is not None:
  68         #renew = request.GET.get('renew', True)
  69         #if not renew:
  70         # TODO: check user SSO session
  71         try:
  72             ticket = ServiceTicket.objects.get(ticket=ticket_string)
  73             assert ticket.service == service
  74             username = ticket.user.username
  75             ticket.delete()
  76             return HttpResponse("yes\n%s\n" % username)
  77         except:
  78             pass
  79     return HttpResponse("no\n\n")
  80
  81
  82 def logout(request, template_name='cas/logout.html', \
  83                 auto_redirect=settings.CAS_AUTO_REDIRECT_AFTER_LOGOUT):
  84     url = request.GET.get('url', None)
  85     if request.user.is_authenticated():
  86         auth_logout(request)
  87         if url and auto_redirect:
  88             return HttpResponseRedirect(url)
  89     return render_to_response(template_name, {'url': url}, \
  90                               context_instance=RequestContext(request))
  91
  92
  93 def service_validate(request):
  94     """Validate ticket via CAS v.2 protocol"""
  95     service = request.GET.get('service', None)
  96     ticket_string = request.GET.get('ticket', None)
  97     if service is None or ticket_string is None:
  98         return _cas2_error_response(INVALID_REQUEST)
  99
 100     try:
 101         ticket = ServiceTicket.objects.get(ticket=ticket_string)
 102     except ServiceTicket.DoesNotExist:
 103         return _cas2_error_response(INVALID_TICKET)
 104
 105     if ticket.service != service:
 106         ticket.delete()
 107         return _cas2_error_response(INVALID_SERVICE)
 108
 109     user = ticket.user
 110     ticket.delete()
 111     return _cas2_sucess_response(user)
 112
 113
 114 def _cas2_error_response(code):
 115     return HttpResponse(u''''<cas:serviceResponse xmlns:cas="http://www.yale.edu/tp/cas">
 116             <cas:authenticationFailure code="%(code)s">
 117                 %(message)s
 118             </cas:authenticationFailure>
 119         </cas:serviceResponse>''' % {
 120             'code': code,
 121             'message': dict(ERROR_MESSAGES).get(code)
 122     }, mimetype='text/xml')
 123
 124
 125 def _cas2_sucess_response(user):
 126     return HttpResponse(auth_success_response(user), mimetype='text/xml')
 127
 128
 129 def auth_success_response(user):
 130     from attribute_formatters import CAS, NSMAP, etree
 131
 132     response = etree.Element(CAS + 'serviceResponse', nsmap=NSMAP)
 133     auth_success = etree.SubElement(response, CAS + 'authenticationSuccess')
 134     username = etree.SubElement(auth_success, CAS + 'user')
 135     username.text = user.username
 136
 137     if settings.CAS_CUSTOM_ATTRIBUTES_CALLBACK:
 138         callback = get_callable(settings.CAS_CUSTOM_ATTRIBUTES_CALLBACK)
 139         attrs = callback(user)
 140         if len(attrs) > 0:
 141             formater = get_callable(settings.CAS_CUSTOM_ATTRIBUTES_FORMATER)
 142             formater(auth_success, attrs)
 143     return unicode(etree.tostring(response, encoding='utf-8'), 'utf-8')