God Damn it Plus net

So recently I changed my mail server over to postfix, this not that long after I ranted about e-mail security with plusnet. It turns out this has led to an interesting problem. So SSL settings were set pretty strictly on the smtps port, so only strong TLSv1.2 ciphers were available. On the smtp port I was a little more permissive, as long as it was TLSv1.2 it would accept even very weak ciphers (well a weak cipher is better than no cipher at all, and I was accepting mail that didn't use the starttls command) and everything was good. Accept that it turns out emails coming from Plusnet's mail servers was failing, they would connect, try to starttls, not like any of the ciphers and fail, breaking the connection. Once they tried again they didn't remember that starttls didn't work so they tried again. Until the mail timed out, and was bounced. So I've had to make the setting even more permissive, as getting emails from people I know on plusnet (like my Father for example) is sort of important.

posted at 04:44:47 PM on 21 Feb 2017 by Craig Stewart

Tags:not-good-enough fail rant email security sysadmin 

Oh Shit, perhaps I should change career?

So the government have passed the Investigatory Powers Act, which is pretty terrible, but it turns out it is worse than I realised! So perhaps it is not a good time to work in IT in the UK?

posted at 09:44:21 PM on 30 Nov 2016 by Craig Stewart

Tags:politics security not-good-enough comment 

PlusNet and email security whilst out and about.

So, I use PlusNet as my ISP. I have an email address with them where they send updates about my account. It's also been used in the past to sign up to various things that I haven't bothered to update to a new email address. PlusNet's email servers do not require authentication to send email from my home connection, which is fair enough really. But they also don't support SSL for authentication from my connection. So my username and password (which is unique to this account) has to be sent in plain text, now as this is to my ISP over my ISP connection (and I trust my own network) it's not the end of the world. However, I also have a shiny smart phone, and that allows me to connect to my own email server, over SSL (that until recently wasn't as secure as it should be) as it should be when connecting over the internet, from untrusted, or unknown networks. It also allows me to use multiple different email inboxes at once. So I could add my PlusNet email address. They even have a handy guide on setting up email on android phones. And that's where the problems start. That guide sets up email without SSL, or TLS, but it requires username and password authentication. So I'd only be able to use it on my home network. What happens if I forget to turn email sync off? My details would be put at risk!

So what should a good sysadmin do? Should I leave the ISP email only on my home PC? Should I take the risk and add the email to my phone anyway?

Well as a paranoid sysadmin I wasn't willing to take the risk. And that was that. But frankly that was annoying me, so I decided to set up an SSL terminator for my ISP email using my own SSL cert. So I can get my email, from my ISP confident in the knowledge that only my ISP can intercept the username and password pair that I use with my ISP. I use non-standard ports for the ISP connections, and listen using stunnel. This would be a problem if I was supporting users as it would add a level of complexity to the instructions I'd have to give them, but as I only have to support myself I can cope.

posted at 11:06:37 PM on 9 Apr 2016 by Craig Stewart

Tags:email not-good-enough ssl rant comment