All adhoc MAC applications have been updated to use HMAC, using SHA1 to
generate unique keys for each application based on the SECRET_KEY, which is
common practice for this situation. In all cases, backwards compatibility
with existing hashes has been maintained, aiming to phase this out as per
the normal deprecation process. In this way, under most normal
circumstances the old hashes will have expired (e.g. by session expiration
etc.) before they become invalid.
In the case of the messages framework and the cookie backend, which was
already using HMAC, there is the possibility of a backwards incompatibility
if the SECRET_KEY is shorter than the default 50 bytes, but the low
likelihood and low impact meant compatibility code was not worth it.
All known instances where tokens/hashes were compared using simple string
equality, which could potentially open timing based attacks, have also been
fixed using a constant-time comparison function.
There are no known practical attacks against the existing implementations,
so these security improvements will not be backported.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@14218 bcc190cf-cafb-0310-a4f2-bffc1f526a37
Also made the FileSession backend consistent with other backends in one
corner case uncovered by the conversion, namely that the backend should
create a new key if the one passed in is invalid.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@13482 bcc190cf-cafb-0310-a4f2-bffc1f526a37
sesssion. This means the user will see their session preserved across a login
boundary, but somebody snooping the anonymous session key won't be able to view
the authenticated session data.
This is the final piece of the session key handling changes.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@8459 bcc190cf-cafb-0310-a4f2-bffc1f526a37
a cookie) with no corresponding entry in the database.
This only affected the database backend, but I've applied the same fix to all
three backends for robustness.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@8351 bcc190cf-cafb-0310-a4f2-bffc1f526a37
regenerates the key. Used to ensure the caller gets a fresh session at logout,
for example.
Based on a patch from mrts. Refs #7515.
git-svn-id: http://code.djangoproject.com/svn/django/trunk@8342 bcc190cf-cafb-0310-a4f2-bffc1f526a37
Alex Gaynor
Carl Meyer
Russell Keith-Magee
Luke Plant
Malcolm Tredinnick
Jacob Kaplan-Moss
Adrian Holovaty