[py3] Fix encoding issues in contrib.sessions

django/contrib/sessions/backends/base.py

@@ -1,3 +1,5 @@
+from __future__ import unicode_literals
+
 import base64
 import time
 from datetime import datetime, timedelta
@@ -12,6 +14,7 @@ from django.utils.crypto import constant_time_compare
 from django.utils.crypto import get_random_string
 from django.utils.crypto import salted_hmac
 from django.utils import timezone
+from django.utils.encoding import smart_bytes
 
 class CreateError(Exception):
     """
@@ -78,15 +81,15 @@ class SessionBase(object):
         "Returns the given session dictionary pickled and encoded as a string."
         pickled = pickle.dumps(session_dict, pickle.HIGHEST_PROTOCOL)
         hash = self._hash(pickled)
-        return base64.encodestring(hash + ":" + pickled)
+        return base64.encodestring(hash.encode() + b":" + pickled)
 
     def decode(self, session_data):
-        encoded_data = base64.decodestring(session_data)
+        encoded_data = base64.decodestring(smart_bytes(session_data))
         try:
             # could produce ValueError if there is no ':'
-            hash, pickled = encoded_data.split(':', 1)
+            hash, pickled = encoded_data.split(b':', 1)
             expected_hash = self._hash(pickled)
-            if not constant_time_compare(hash, expected_hash):
+            if not constant_time_compare(hash.decode(), expected_hash):
                 raise SuspiciousOperation("Session data corrupted")
             else:
                 return pickle.loads(pickled)

django/contrib/sessions/backends/db.py

@@ -1,7 +1,6 @@
 from django.contrib.sessions.backends.base import SessionBase, CreateError
 from django.core.exceptions import SuspiciousOperation
 from django.db import IntegrityError, transaction, router
-from django.utils.encoding import force_text
 from django.utils import timezone
 
 
@@ -18,7 +17,7 @@ class SessionStore(SessionBase):
                 session_key = self.session_key,
                 expire_date__gt=timezone.now()
             )
-            return self.decode(force_text(s.session_data))
+            return self.decode(s.session_data)
         except (Session.DoesNotExist, SuspiciousOperation):
             self.create()
             return {}