Add PG Community Auth support.

7 files changed, 242 insertions, 10 deletions

diff --git a/web/pgperffarm/auth.py b/web/pgperffarm/auth.py
new file mode 100644
index 0000000..5ce4593
--- /dev/null
+++ b/web/pgperffarm/auth.py
@@ -0,0 +1,205 @@
+#
+# 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 (typically /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 json
+import socket
+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'):
+		return HttpResponse("Missing IV in url!", status=400)
+	if not request.GET.has_key('d'):
+		return HttpResponse("Missing data in url!", status=400)
+
+	# 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:
+		return HttpResponse("Invalid encrypted data received.", status=400)
+
+	# Check the timestamp in the authentication
+	if (int(data['t'][0]) < time.time() - 10):
+		return HttpResponse("Authentication token too old.", status=400)
+
+	# 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:
+		# 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 [email protected], indicating the username
+and email address from above, and we'll manually merge 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:
+			return HttpResponse("Invalid encrypted data received.", status=400)
+		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)
+	return HttpResponse("Authentication successful, but don't know where to redirect!", status=500)
+
+
+# Perform a search in the central system. Note that the results are returned as an
+# array of dicts, and *not* as User objects. To be able to for example reference the
+# user through a ForeignKey, a User object must be materialized locally. We don't do
+# that here, as this search might potentially return a lot of unrelated users since
+# it's a wildcard match.
+# Unlike the authentication, searching does not involve the browser - we just make
+# a direct http call.
+def user_search(searchterm=None, userid=None):
+	# If upsteam isn't responding quickly, it's not going to respond at all, and
+	# 10 seconds is already quite long.
+	socket.setdefaulttimeout(10)
+	if userid:
+		q = {'u': userid}
+	else:
+		q = {'s': searchterm}
+
+	u = urllib.urlopen('%ssearch/?%s' % (
+		settings.PGAUTH_REDIRECT,
+		urllib.urlencode(q),
+		))
+	(ivs, datas) = u.read().split('&')
+	u.close()
+
+	# Decryption time
+	decryptor = AES.new(base64.b64decode(settings.PGAUTH_KEY),
+						AES.MODE_CBC,
+						base64.b64decode(ivs, "-_"))
+	s = decryptor.decrypt(base64.b64decode(datas, "-_")).rstrip(' ')
+	j = json.loads(s)
+
+	return j
diff --git a/web/pgperffarm/settings.py b/web/pgperffarm/settings.py
index 8381541..29d74dc 100644
--- a/web/pgperffarm/settings.py
+++ b/web/pgperffarm/settings.py
@@ -106,5 +106,9 @@ STATICFILES_DIRS = [
     "static/",
 ]
 
+AUTHENTICATION_BACKENDS = (
+     'pgperffarm.auth.AuthBackend',
+)
+ 
 # Load local settings overrides
 from settings_local import *
diff --git a/web/pgperffarm/settings_local.py.in b/web/pgperffarm/settings_local.py.in
index fbe4ac6..39618d4 100644
--- a/web/pgperffarm/settings_local.py.in
+++ b/web/pgperffarm/settings_local.py.in
@@ -10,3 +10,5 @@ DATABASES={
                 }
         }
 
+PGAUTH_REDIRECT=''
+PGAUTH_KEY=''
\ No newline at end of file
diff --git a/web/pgperffarm/urls.py b/web/pgperffarm/urls.py
index e07097f..ea9962b 100644
--- a/web/pgperffarm/urls.py
+++ b/web/pgperffarm/urls.py
@@ -21,7 +21,12 @@ urlpatterns = [
     url(r'^$', 'pgperffarm.views.index', name='index'),
     url(r'^/licence$', 'pgperffarm.views.licence', name='licence'),
     url(r'^/ppolicy$', 'pgperffarm.views.ppolicy', name='ppolicy'),
-    
+
+    # Auth system integration
+    url(r'^(?:account/)?login/?$', 'pgperffarm.auth.login'),
+    url(r'^(?:account/)?logout/?$', 'pgperffarm.auth.logout'),
+    url(r'^auth_receive/$', 'pgperffarm.auth.auth_receive'),
+  
     # Admin site
     url(r'^admin/', include(admin.site.urls)),
     
diff --git a/web/pgperffarm/views.py b/web/pgperffarm/views.py
index ecdf975..7fdcf34 100644
--- a/web/pgperffarm/views.py
+++ b/web/pgperffarm/views.py
@@ -1,17 +1,19 @@
 """Views for the core PGPerfFarm app"""
 
 from django.shortcuts import render_to_response
-from django.http import HttpResponse, Http404
-from django.template import TemplateDoesNotExist, loader, Context
+from django.template import RequestContext
 
 import datetime
 
 # Handle the static pages
 def index(request):
-        return render_to_response('index.html')
+    return render_to_response('index.html', 
+        context_instance=RequestContext(request))
         
 def licence(request):
-        return render_to_response('licence.html')
+    return render_to_response('licence.html', 
+        context_instance=RequestContext(request))
         
 def ppolicy(request):
-        return render_to_response('ppolicy.html')
\ No newline at end of file
+    return render_to_response('ppolicy.html', 
+        context_instance=RequestContext(request))
\ No newline at end of file
diff --git a/web/templates/admin/login.html b/web/templates/admin/login.html
new file mode 100644
index 0000000..e9e7257
--- /dev/null
+++ b/web/templates/admin/login.html
@@ -0,0 +1,11 @@
+<html>
+<head>
+<meta http-equiv="refresh" content="0;url={% url 'pgperffarm.auth.login' %}/?next=/admin/"></meta>
+</head>
+<body>
+<h1>Redirect</h1>
+<p>
+Redirect <a href="{% url 'pgperffarm.auth.login' %}/?next=/admin/">here</a>
+</p>
+</body>
+</html>
\ No newline at end of file
diff --git a/web/templates/body.html b/web/templates/body.html
index 7e06dad..08313b5 100644
--- a/web/templates/body.html
+++ b/web/templates/body.html
@@ -38,16 +38,19 @@
             </li>
           </ul>
           <ul class="nav navbar-nav navbar-right">
+            {% if user.is_authenticated %}
             <li class="dropdown">
-              <a href="#" class="dropdown-toggle" data-toggle="dropdown">{% gravatar user.email 18 %} {{ request.user }}<b class="caret"></b></a>
+              <a href="#" class="dropdown-toggle" data-toggle="dropdown">{% gravatar user.email 18 %} {{ user }}<b class="caret"></b></a>
               <ul class="dropdown-menu">
-                {% if request.user.is_superuser %}
+                {% if user.is_staff %}
                 <li><a href="{% url 'admin:index' %}">Admin Site</a></li>
-                <li><a href="{% url 'django-admindocs-docroot' %}">Admin Docs</a></li>
                 {% endif %}
-                <li><a href="#">Logout</a></li>
+                <li><a href="{% url 'pgperffarm.auth.logout' %}">Logout</a></li>
               </ul>
             </li>
+            {% else %}
+            <li><a href="{% url 'pgperffarm.auth.login' %}/?next={{ request.path }}">Login</a></li>
+            {% endif %}
           </ul>
         </div>
       </div>