Awesome

Silverstripe CMS Session Manager

Allow members to manage and revoke access to multiple login sessions across devices.

Developer Details

The module introduces a new database record type: LoginSession. On first login, it creates a new record of this type, recording the IP and User-Agent, and associates it with the member (via LogInAuthenticationHandler). The record identifier is stored in the PHP session, so it can be retrieved on subsequent requests.

On each request, a middleware (LoginSessionMiddleware) checks if the current PHP session is pointing to a valid LoginSession record. If a valid record is found, it will update the LastAccessed date. Otherwise, it will force a logout, destroying the PHP session.

A periodic process (GarbageCollectionService) cleans up expired LoginSession records. Due to the way PHP sessions operate, it can not expire those sessions as well. The PHP sessions will be invalidated on next request through LoginSessionMiddleware, unless they expire independently beforehand (through PHP's own session expiry logic).

Silverstripe allows persisting login state via a "Keep me signed in" feature. These RememberLoginHash records have their own expiry date. This module associates them to LoginSession records, and ensures their expiry is consistent with the new session behaviour (see "Configuration" below for details).

The LoginSession tracks the IP address and user agent making the requests in order to make different sessions easier to identify in the user interface. It does not use changes to this metadata to invalidate sessions.

Logged in users have the ability to see their own active sessions across all devices and browsers where they have logged in, and can choose to log out any of those sessions.

Administrators can revoke all active sessions for all users by triggering the dev/tasks/InvalidateAllSessions task either in the browser or via the CLI. Note that this will also revoke the session of the user activating the task, so if this is triggered via the browser, that user will need to log back in to perform further actions.

Compatibility

The module should work independently of the storage mechanism used for PHP sessions (file-based sticky sessions, file-based sessions on a shared filesystem, silverstripe/dynamodb, silverstripe/hybridsessions).

It is also compatible with the Silverstripe MFA module suite.

Caveats

• Every request with a logged-in member causes a database write (updating LoginSession), potentially affecting performance
• Restoring a database from an older snapshot will invalidate current sessions.
• PHP sessions can become out of sync with LoginSession objects. Both can exist beyond their expiry date. This is not an issue in practice since the association between the two is checked on each session-based request (through LoginSessionMiddleware).

Configuration

Removing "remember me" tokens across devices on logout

Session-manager provides an explicit way to terminate individual sessions and their attached "Keep me signed in" tokens. So this module sets SilverStripe\Security\RememberLoginHash.logout_across_devices to false.

To restore the old behaviour with session manager installed, add the following YML config to your project:

---
Name: myproject-rememberloginhash
After:
  - '#session-manager-rememberloginhash'
---
SilverStripe\Security\RememberLoginHash:
  logout_across_devices: true

Please note, this configuration only removes "remember me" tokens on logout, it does not terminate active sessions across devices on logout.

Read Saved User Logins to learn how to configure the "Keep me signed in" feature for your members.

Session timeout

Non-persisted login sessions (those where the member hasn’t ticked "Keep me signed in") should expire after a period of inactivity, so that they’re removed from the list of active sessions even if the member closes their browser without completing the “log out” action. The length of time before expiry matches the SilverStripe\Control\Session.timeout value if one is set, otherwise falling back to a default of one hour. This default can be changed via the following config setting:

SilverStripe\SessionManager\Models\LoginSession:
  default_session_lifetime: 3600 # Default value: 1 hour in seconds

Note that if the member’s session expires before this timeout (e.g. a short session.gc_maxlifetime PHP ini setting), they will still be logged out. There will just be an extra session shown in the list of active sessions, even though no one can access it.

Garbage collection

Expired sessions need to be cleaned up periodically to avoid bloating the database. There are two methods available to manage this:

Via symbiote/silverstripe-queuedjobs (recommended)

If you have the symbiote/silverstripe-queuedjobs module installed and configured, garbage collection will run automatically every 1 day via GarbageCollectionJob, and no further action is required. This job will be automatically created if it does not exist on dev/build.

Via LoginSessionGarbageCollectionTask

Alternatively, you can create a system cron entry to run the LoginSessionGarbageCollectionTask directly on a regular cadence:

`*/5 * * * * /path/to/webroot/vendor/bin/sake dev/tasks/LoginSessionGarbageCollectionTask