--- /dev/null
+#
+# Django module to support postgresql.org community authentication 2.0
+#
+# The main location for this module is the pgweb git repository hosted
+# on git.postgresql.org - look there for updates.
+#
+# To integrate with django, you need the following:
+# * Make sure the view "login" from this module is used for login
+# * Map an url somwehere (typicall /auth_receive/) to the auth_receive
+# view.
+# * In settings.py, set AUTHENTICATION_BACKENDS to point to the class
+# AuthBackend in this module.
+# * (And of course, register for a crypto key with the main authentication
+# provider website)
+# * If the application uses the django admin interface, the login screen
+# has to be replaced with something similar to login.html in this
+# directory (adjust urls, and name it admin/login.html in any template
+# directory that's processed before the default django.contrib.admin)
+#
+
+from django.http import HttpResponse, HttpResponseRedirect
+from django.contrib.auth.models import User
+from django.contrib.auth.backends import ModelBackend
+from django.contrib.auth import login as django_login
+from django.contrib.auth import logout as django_logout
+from django.conf import settings
+
+import base64
+import urlparse
+import urllib
+from Crypto.Cipher import AES
+from Crypto.Hash import SHA
+from Crypto import Random
+import time
+
+class AuthBackend(ModelBackend):
+ # We declare a fake backend that always fails direct authentication -
+ # since we should never be using direct authentication in the first place!
+ def authenticate(self, username=None, password=None):
+ raise Exception("Direct authentication not supported")
+
+
+####
+# Two regular django views to interact with the login system
+####
+
+# Handle login requests by sending them off to the main site
+def login(request):
+ if request.GET.has_key('next'):
+ # Put together an url-encoded dict of parameters we're getting back,
+ # including a small nonce at the beginning to make sure it doesn't
+ # encrypt the same way every time.
+ s = "t=%s&%s" % (int(time.time()), urllib.urlencode({'r': request.GET['next']}))
+ # Now encrypt it
+ r = Random.new()
+ iv = r.read(16)
+ encryptor = AES.new(SHA.new(settings.SECRET_KEY).digest()[:16], AES.MODE_CBC, iv)
+ cipher = encryptor.encrypt(s + ' ' * (16-(len(s) % 16))) # pad to 16 bytes
+
+ return HttpResponseRedirect("%s?d=%s$%s" % (
+ settings.PGAUTH_REDIRECT,
+ base64.b64encode(iv, "-_"),
+ base64.b64encode(cipher, "-_"),
+ ))
+ else:
+ return HttpResponseRedirect(settings.PGAUTH_REDIRECT)
+
+# Handle logout requests by logging out of this site and then
+# redirecting to log out from the main site as well.
+def logout(request):
+ if request.user.is_authenticated():
+ django_logout(request)
+ return HttpResponseRedirect("%slogout/" % settings.PGAUTH_REDIRECT)
+
+# Receive an authentication response from the main website and try
+# to log the user in.
+def auth_receive(request):
+ if request.GET.has_key('s') and request.GET['s'] == "logout":
+ # This was a logout request
+ return HttpResponseRedirect('/')
+
+ if not request.GET.has_key('i'):
+ raise Exception("Missing IV")
+ if not request.GET.has_key('d'):
+ raise Exception("Missing data!")
+
+ # Set up an AES object and decrypt the data we received
+ decryptor = AES.new(base64.b64decode(settings.PGAUTH_KEY),
+ AES.MODE_CBC,
+ base64.b64decode(str(request.GET['i']), "-_"))
+ s = decryptor.decrypt(base64.b64decode(str(request.GET['d']), "-_")).rstrip(' ')
+
+ # Now un-urlencode it
+ try:
+ data = urlparse.parse_qs(s, strict_parsing=True)
+ except ValueError, e:
+ raise Exception("Invalid encrypted data received.")
+
+ # Check the timestamp in the authentication
+ if (int(data['t'][0]) < time.time() - 10):
+ raise Exception("Authentication token too old.")
+
+ # Update the user record (if any)
+ try:
+ user = User.objects.get(username=data['u'][0])
+ # User found, let's see if any important fields have changed
+ changed = False
+ if user.first_name != data['f'][0]:
+ user.first_name = data['f'][0]
+ changed = True
+ if user.last_name != data['l'][0]:
+ user.last_name = data['l'][0]
+ changed = True
+ if user.email != data['e'][0]:
+ user.email = data['e'][0]
+ changed= True
+ if changed:
+ user.save()
+ except User.DoesNotExist, e:
+ # User not found, create it!
+
+ # NOTE! We have some legacy users where there is a user in
+ # the database with a different userid. Instead of trying to
+ # somehow fix that live, give a proper error message and
+ # have somebody look at it manually.
+ if User.objects.filter(email=data['e'][0]).exists():
+ return HttpResponse("""A user with email %s already exists, but with
+a different username than %s.
+
+This is almost certainly caused by some legacy data in our database.
+Please send an email to webmaster@postgresql.eu, indicating the username
+and email address from above, and we'll manually marge the two accounts
+for you.
+
+We apologize for the inconvenience.
+""" % (data['e'][0], data['u'][0]), content_type='text/plain')
+
+ user = User(username=data['u'][0],
+ first_name=data['f'][0],
+ last_name=data['l'][0],
+ email=data['e'][0],
+ password='setbypluginnotasha1',
+ )
+ user.save()
+
+ # Ok, we have a proper user record. Now tell django that
+ # we're authenticated so it persists it in the session. Before
+ # we do that, we have to annotate it with the backend information.
+ user.backend = "%s.%s" % (AuthBackend.__module__, AuthBackend.__name__)
+ django_login(request, user)
+
+ # Finally, check of we have a data package that tells us where to
+ # redirect the user.
+ if data.has_key('d'):
+ (ivs, datas) = data['d'][0].split('$')
+ decryptor = AES.new(SHA.new(settings.SECRET_KEY).digest()[:16],
+ AES.MODE_CBC,
+ base64.b64decode(ivs, "-_"))
+ s = decryptor.decrypt(base64.b64decode(datas, "-_")).rstrip(' ')
+ try:
+ rdata = urlparse.parse_qs(s, strict_parsing=True)
+ except ValueError:
+ raise Exception("Invalid encrypted data received.")
+ if rdata.has_key('r'):
+ # Redirect address
+ return HttpResponseRedirect(rdata['r'][0])
+ # No redirect specified, see if we have it in our settings
+ if hasattr(settings, 'PGAUTH_REDIRECT_SUCCESS'):
+ return HttpResponseRedirect(settings.PGAUTH_REDIRECT_SUCCESS)
+ raise Exception("Authentication successful, but don't know where to redirect!")
projects / pgcommitfest2.git / commitdiff