Date: 2022-09-13
Accepted (lazy consensus).
Implemented.
Delegation is a common feature for email servers:
As user A I want to access mailbox of user B.
James currently supports a similar feature called impersonation:
As an administrator I want to acces mailbox of user B.
Impersonation can for instance be used to perform migrations with tools like IMAP-Sync.
Implement delegation in Apache James (opt in).
Reuse APIs used for impersonation to also back delegation up. Technically if user B delegates his account to user A then user A can impersonate user B.
Stored delegated access in a Cassandra database and expose it through webadmin.
Support delegation while logging in IMAP/SMTP. Both LOGIN/PLAIN authentication and OIDC authentication are supported.
Logging traces belongs to the target user and not the user that really authenticated though an intermediate log upon logging should allow a correlation.
Associated risk:
improper authorization attack class and might result in data leaks / modification / deletion. However, as delegation is performed upon logging the attack surface is limited, and typically simpler than traditional right management systems.JMAP integration. We can expose delegated accounts through the JMAP session object and support using non-default JMAP accounts.
This might come at the price of one Cassandra read per JMAP request when interacting with delegated accounts.