MBOX-Line: From davidmaxwaterman at fastmail.co.uk  Wed Nov  2 20:26:58 2005
To: imap-protocol@u.washington.edu
From: Max Waterman <davidmaxwaterman@fastmail.co.uk>
Date: Fri Jun  8 12:34:36 2018
Subject: [Imap-protocol] username/password
In-Reply-To: <Pine.OSX.4.64.0511022009390.533@pangtzu.panda.com>
References: <436988D9.8040106@fastmail.co.uk>
	<Pine.OSX.4.64.0511022009390.533@pangtzu.panda.com>
Message-ID: <43699192.2040701@fastmail.co.uk>

Thanks for the prompt response and clear explanation.

It seems that the options are :

1) propose a new RFC to split the username/password, which can then be 
implemented
2) use a separate servers for secure and insecure users (I suppose a 
second NIC would suffice?)

Is that correct?

Max.

Mark Crispin wrote:
> Your question is difficult to answer, because it makes an incorrect 
> premise.  That premise is that the server "asks" for a password.
> 
> The server does not "ask" for a password in IMAP; rather, the client 
> chooses to provide one.
> 
> The server MAY announce that it refuses passwords on a global basis via 
> the LOGINDISABLED capability.  Any client which sends a password to a 
> server which has announced LOGINDISABLED is non-compliant with the IMAP 
> specification and should not be used.
> 
> The standard configuration of UW imapd, in accordance with the IMAP 
> specification (RFC 3501), makes such an announcement on non-SSL/TLS 
> sessions; and in that state will reject any password even if the 
> password is correct.  In that state, UW imapd allows other means of 
> authentication that do not involve passwords.  If the session negotiates 
> TLS encryption, the UW imapd will retract the LOGINDISABLED announcement 
> and allow password authentication.
> 
> For other servers, you will need to read the vendor's documentation.
> 
> When announced, LOGINDISABLED is a global restriction.  It is not 
> possible to allow passwords for some users and disallow passwords for 
> other users. This is because the user name and password are sent together.
> 
> -- Mark --
> 
> http://panda.com/mrc
> Democracy is two wolves and a sheep deciding what to eat for lunch.
> Liberty is a well-armed sheep contesting the vote.


