Re: exim4 and TLS Once Again

[Brian <ad44@cityscape.co.uk>]

On Wed 30 May 2018 at 20:58:12 -0400, Michael Stone wrote:

> On Wed, May 30, 2018 at 06:22:49PM -0500, David Wright wrote:
> > AIUI 587 is the standard email submission port and 465 is now
> > deprecated but often still in use. I think they differ in the
> > details of how they handle encrypting the session.
> 
> > From a protocol standpoint 587/tcp is identical to 25/tcp, with the
> distinction that it is designated for a end-users to submit messages for
> delivery rather than accepting mail for delivery from external mail relays.
> The expectation is that there is authentication of the submission, either
> via allowed IPs, SMTP AUTH, or some other mechanism.  Networks can block
> port 25 to reduce spam originating from the network, but allow 587 for
> visitors to submit email to their provider for delivery. Encryption is
> activated with STARTTLS.

TLS is not offered by suddenlink.net on port 587:

 brian@stretch:~# nc smtp.suddenlink.net 587
 220 omta01.suddenlink.net ESMTP server (InterMail vM.8.04.03.22 201-2389-100-167-20150619) ready Fri, 1 Jun 2018 06:45:17 -0500
 ehlo test
 250-omta01.suddenlink.net
 250-HELP
 250-XREMOTEQUEUE
 250-ETRN
 250-AUTH=LOGIN PLAIN
 250-AUTH LOGIN PLAIN
 250-PIPELINING
 250-DSN
 250-8BITMIME
 250 SIZE 52428800

Exim will have to use "AUTH_CLIENT_ALLOW_NOTLS_PASSWORDS = true".

-- 
Brian.