MBOX-Line: From norman at apache.org  Sun Feb  6 22:31:38 2011
To: imap-protocol@u.washington.edu
From: Norman Maurer <norman@apache.org>
Date: Fri Jun  8 12:34:45 2018
Subject: [Imap-protocol] Max literal line length
Message-ID: <AANLkTim51w9wOE2Ubis+-vucUi4ut42DZbO-v_Ffg6g8@mail.gmail.com>

Hi there,

we are currently implementing a NIO-bases IMAP-Server. We use a
line-delimiter for break down the "buffers" and push them down to the
processors. This works fine so far but we are a bit concerned about
how to limit the max buffer size in a case of a very-very long line.
We saw there is a rfc which refer to something about 8000 octets per
command-line.

RFC 2683 section 3.2.1 (imap4 implementation
recommendations):

"For its part, a server should allow for a command line of at least
 8000 octets. This provides plenty of leeway for accepting reasonable
 length commands from clients. The server should send a BAD response
 to a command that does not end within the server's maximum accepted
 command length."

But I think this only is true for commands lines without the literal
usage. So at the moment we limit a line to be max of 64kb to guard
against a DOS but I'm not sure its really the way to go. Anyone has
some expirience with such needs ?

Thx,
Norman

