Hi,
sorry, I know this is not directly related to postfix but I know that
there are several very experienced people reading this list. My question
is how you (the people that use and administer mailservers) handle the
localpart case sensivity according to rfc5321:
"The local-part of a mailbox MUST BE treated as case sensitive."
Background ist the development of postfwd rate limiting, which allows
amongst others to place maximum values (count or volume) for sender or
recipient addresses. To do so postfwd creates a hash with the given
address as index. At the moment it is easy to "trick" such limits by
varying the case of the addresses, meaning that postfwd will create
different counters for bob@alice.local, BoB@alice.local and bob@AlicE.local.
No question - with future versions postfwd will definitely treat the
domainpart case-insensitive, so that bob@alice.local and bob@AlicE.local
will have the same counter. But for the localpart I see two options,
wondering which I should choose:
1.) Being strictly rfc5321 compliant:
By default postfwd creates two different counters for bob@alice.local
and BoB@alice.local. To change this the admin has to specify
--non-rfc5321-rate-case-sensivity (or s.th. similar).
2.) Being real-world compliant:
By default postfwd uses the same counter for bob@alice.local and
BoB@alice.local. To change this the admin has to specify
--strict-rfc5321-rate-case-sensivity.
What's your opinion on that? Do you know any real-world systems that
distinguish between bob@alice.local and BoB@alice.local (means that both
point to different mailboxes).
Thank you in advance
Jan
