Easy to configure SMTP relay?


Please recommend easy to set up SMTP relay software. I want to run SMTP relay at home and use it for sending e-mail while traveling.

So far I have tried sendmail and qmail, but getting either of them working with authentication is above my skills. So currently I am using FreeBSD default sendmail as an open relay on non-default port. I realise it will get exploited by spammers sooner or later.

I would like to have easy-to-set-up SMTP server, where I just set listen port, username and password. And no crazy fiddling around with tons of config files... SSL/TLS would be nice to have, but auth is a must.
I'd not willing to discourage you but I've never seen a SMTP server with so simple configuration... I've used Sendmail and Postfix. Both are easy enough to setup but Postfix + Dovecot is much easier to configure and customize. If you use system users you'll spare your efforts on configuring authentication backend.
If you already have Sendmail https://www.freebsd.org/doc/handbook/SMTP-Auth.html will be very helpful for you.
As for TLS / SSL this might help:
You will need to use mail/postfix with MySQL for user accounts. A simple SMTP server will not be enough especially if you want functions such as MTA, SMTP. SSL/TLS and user authentications then you will need full-functioning mail server which will be Postfix and Dovecot. I may suggest using iRedMail at http://www.iredmail.org/download.html as it setup everything for you and they have good instructions.

I've build mail servers and its not easy. Misconfigured mail server will make your server vulnerable to hackers so I would suggest using iRedMail for now until you are comfortable building email server yourself.
I second this, since (a) it's FreeBSD-oriented; and (b) the syntax in that Arch Wiki page is outdated. I have to relay mail to two different SMTP servers for two different accounts for work and get periodic(8) reports from my home server, and just set up OpenSMTPD on my laptop yesterday. That guide, the official FAQ, and the excellent man pages made it relatively easy. OpenSMTPD is probably the only SMTP relay/MTA I've managed to set up on my own, since its configuration doesn't look like and arcane grimoire for summoning demons.
Ok, I am back to this problem. I was running SMTP (sendmail) with no auth on non-standard port. But eventually got exploited by some Ukrainean hackers.

Worked fine so far. Just as needed, I and my relatives could send out e-mail from laptop and tablet via home SMTP server when travelling.

Since I was unable to get sendmail working, I now tried OpenSMTPd, but that also seems to be exercise in frustration:

# smtpd -n
/usr/local/etc/mail/smtpd.conf:9: no such table: passwd

# smtpctl update table passwd
smtpd doesn't seem to be running

My goal is to set up SMTP relay with AUTH. For both internal and external network. I want auth to be in separate file, not system /etc/passwd. I don't want e-mail (which I consider inherently insecure) use my SSH passwords (which I consider secure and secret).

I have worked as a junior system and network administrator for 10 years and in that time I have used qmail, sendmail, postfix and exim in different workplaces. But I never set up one SMTP, it was always set up by some senior administrator!
Well, setting something like this up is pretty trivial these days and nothing which a manual doesn't cover.

(edit): Forgot to mention, when you're using Sendmail then /usr/share/sendmail/cf/README will provide some useful information.