1 files changed, 26 insertions, 36 deletions
diff --git a/rest_framework/authentication.py b/rest_framework/authentication.py
index ee5bd2f2..30c78ebc 100644
--- a/rest_framework/authentication.py
+++ b/rest_framework/authentication.py
@@ -1,10 +1,10 @@
 """
-The :mod:`authentication` module provides a set of pluggable authentication classes.
-
-Authentication behavior is provided by mixing the :class:`mixins.RequestMixin` class into a :class:`View` class.
+Provides a set of pluggable authentication policies.
 """
 
 from django.contrib.auth import authenticate
+from django.utils.encoding import smart_unicode, DjangoUnicodeDecodeError
+from rest_framework import exceptions
 from rest_framework.compat import CsrfViewMiddleware
 from rest_framework.authtoken.models import Token
 import base64
@@ -17,25 +17,14 @@ class BaseAuthentication(object):
 
     def authenticate(self, request):
         """
-        Authenticate the :obj:`request` and return a :obj:`User` or :const:`None`. [*]_
-
-        .. [*] The authentication context *will* typically be a :obj:`User`,
-            but it need not be.  It can be any user-like object so long as the
-            permissions classes (see the :mod:`permissions` module) on the view can
-            handle the object and use it to determine if the request has the required
-            permissions or not.
-
-            This can be an important distinction if you're implementing some token
-            based authentication mechanism, where the authentication context
-            may be more involved than simply mapping to a :obj:`User`.
+        Authenticate the request and return a two-tuple of (user, token).
         """
-        return None
+        raise NotImplementedError(".authenticate() must be overridden.")
 
 
 class BasicAuthentication(BaseAuthentication):
     """
-    Base class for HTTP Basic authentication.
-    Subclasses should implement `.authenticate_credentials()`.
+    HTTP Basic authentication against username/password.
     """
 
     def authenticate(self, request):
@@ -43,8 +32,6 @@ class BasicAuthentication(BaseAuthentication):
         Returns a `User` if a correct username and password have been supplied
         using HTTP Basic authentication.  Otherwise returns `None`.
         """
-        from django.utils.encoding import smart_unicode, DjangoUnicodeDecodeError
-
         if 'HTTP_AUTHORIZATION' in request.META:
             auth = request.META['HTTP_AUTHORIZATION'].split()
             if len(auth) == 2 and auth[0].lower() == "basic":
@@ -54,7 +41,8 @@ class BasicAuthentication(BaseAuthentication):
                     return None
 
                 try:
-                    userid, password = smart_unicode(auth_parts[0]), smart_unicode(auth_parts[2])
+                    userid = smart_unicode(auth_parts[0])
+                    password = smart_unicode(auth_parts[2])
                 except DjangoUnicodeDecodeError:
                     return None
 
@@ -62,15 +50,6 @@ class BasicAuthentication(BaseAuthentication):
 
     def authenticate_credentials(self, userid, password):
         """
-        Given the Basic authentication userid and password, authenticate
-        and return a user instance.
-        """
-        raise NotImplementedError('.authenticate_credentials() must be overridden')
-
-
-class UserBasicAuthentication(BasicAuthentication):
-    def authenticate_credentials(self, userid, password):
-        """
         Authenticate the userid and password against username and password.
         """
         user = authenticate(username=userid, password=password)
@@ -85,20 +64,31 @@ class SessionAuthentication(BaseAuthentication):
 
     def authenticate(self, request):
         """
-        Returns a :obj:`User` if the request session currently has a logged in user.
-        Otherwise returns :const:`None`.
+        Returns a `User` if the request session currently has a logged in user.
+        Otherwise returns `None`.
         """
 
         # Get the underlying HttpRequest object
         http_request = request._request
         user = getattr(http_request, 'user', None)
 
-        if user and user.is_active:
-            # Enforce CSRF validation for session based authentication.
-            resp = CsrfViewMiddleware().process_view(http_request, None, (), {})
+        # Unauthenticated, CSRF validation not required
+        if not user or not user.is_active:
+            return
+
+        # Enforce CSRF validation for session based authentication.
+        class CSRFCheck(CsrfViewMiddleware):
+            def _reject(self, request, reason):
+                # Return the failure reason instead of an HttpResponse
+                return reason
+
+        reason = CSRFCheck().process_view(http_request, None, (), {})
+        if reason:
+            # CSRF failed, bail with explicit error message
+            raise exceptions.PermissionDenied('CSRF Failed: %s' % reason)
 
-            if resp is None:  # csrf passed
-                return (user, None)
+        # CSRF passed with authenticated user
+        return (user, None)
 
 
 class TokenAuthentication(BaseAuthentication):