Tags: ssl

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Tuesday, March 3rd, 2020

Insecure

Universal access is at the heart of the World Wide Web. It’s also something I value when I’m building anything on the web. Whatever I’m building, I want you to be able to visit using whatever browser or device that you choose.

Just to be clear, that doesn’t mean that you’re going to have the same experience in an old browser as you are in the latest version of Firefox or Chrome. Far from it. Not only is that not feasible, I don’t believe it’s desirable either. But if you’re using an old browser, while you might not get to enjoy the newest CSS or JavaScript, you should still be able to access a website.

Applying the principle of progressive enhancement makes this emminently doable. As long as I build in a layered way, everyone gets access to the barebones HTML, even if they can’t experience newer features. Crucially, as long as I’m doing some feature detection, those newer features don’t harm older browsers.

But there’s one area where maintaining backward compatibility might well have an adverse effect on modern browsers: security.

I don’t just mean whether or not you’re serving sites over HTTPS. Even if you’re using TLS—Transport Layer Security—not all security is created equal.

Take a look at Mozilla’s very handy SSL Configuration Generator. You get to choose from three options:

  1. Modern. Services with clients that support TLS 1.3 and don’t need backward compatibility.
  2. Intermediate. General-purpose servers with a variety of clients, recommended for almost all systems.
  3. Old. Compatible with a number of very old clients, and should be used only as a last resort.

Because I value universal access, I should really go for the “old” setting. That ensures my site is accessible all the way back to Android 2.3 and Safari 1. But if I do that, I will be supporting TLS 1.0. That’s not good. My site is potentially vulnerable.

Alright then, I’ll go for “intermediate”—that’s the recommended level anyway. Now I’m no longer providing TLS 1.0 support. But that means some older browsers can no longer access my site.

This is exactly the situation I found myself in with The Session. I had a score of A+ from SSL Labs. I was feeling downright smug. Then I got emails from actual users. One had picked up an old Samsung tablet second hand. Another was using an older version of Safari. Neither could access the site.

Sure enough, if you cut off TLS 1.0, you cut off Safari below version six.

Alright, then. Can’t they just upgrade? Well …no. Apple has tied Safari to OS X. If you can’t upgrade your operating system, you can’t upgrade your browser. So if you’re using OS X Mountain Lion, you’re stuck with an insecure version of Safari.

Fortunately, you can use a different browser. It’s possible to install, say, Firefox 37 which supports TLS 1.2.

On desktop, that is. If you’re using an older iPhone or iPad and you can’t upgrade to a recent version of iOS, you’re screwed.

This isn’t an edge case. This is exactly the kind of usage that iPads excel at: you got the device a few years back just to do some web browsing and not much else. It still seems to work fine, and you have no incentive to buy a brand new iPad. And nor should you have to.

In that situation, you’re stuck using an insecure browser.

As a site owner, I can either make security my top priority, which means you’ll no longer be able to access my site. Or I can provide you access, which makes my site less secure for everyone. (That’s what I’ve done on The Session and now my score is capped at B.)

What I can’t do is tell you to install a different browser, because you literally can’t. Sure, technically you can install something called Firefox from the App Store, or you can install something called Chrome. But neither have anything to do with their desktop counterparts. They’re differently skinned versions of Safari.

Apple refuses to allow browsers with any other rendering engine to be installed. Their reasoning?

Security.

Thursday, October 4th, 2018

Picture 1 Picture 2 Picture 3

Kanelbullens dag!

Monday, January 22nd, 2018

We need more phishing sites on HTTPS!

All the books, Montag.

If we want a 100% encrypted web then we need to encrypt all sites, despite whether or not you agree with what they do/say/sell/etc… 100% is 100% and it includes the ‘bad guys’ too.

Thursday, December 21st, 2017

Extended Validation is Broken

How a certificate with extended validation makes it easier to phish. But I think the title could be amended—here’s what’s really broken:

On Safari, the URL is completely hidden! This means the attacker does not even need to register a convincing phishing domain. They can register anything, and Safari will happily cover it with a nice green bar.

Monday, November 27th, 2017

SSL Issuer Popularity - NetTrack.info

This graph warms the cockles of my heart. It’s so nice to see a genuinely good project like Let’s Encrypt come in and upset the applecart of a sluggish monopolistic industry.

Monday, January 30th, 2017

Thursday, January 19th, 2017

Certified Malice – text/plain

Following from that great post about the “zone of death” in browsers, Eric Law looks at security and trust in a world where certificates are free and easily available …even to the bad guys.

Saturday, December 10th, 2016

Certbot renewals with Apache

I wrote a while back about switching to HTTPS on Apache 2.4.7 on Ubuntu 14.04 on Digital Ocean. In that post, I pointed to an example .conf file.

I’ve been having a few issues with my certificate renewals with Certbot (the artist formerly known as Let’s Encrypt). If I did a dry-run for renewing my certificates…

/etc/certbot-auto renew --dry-run

… I kept getting this message:

Encountered vhost ambiguity but unable to ask for user guidance in non-interactive mode. Currently Certbot needs each vhost to be in its own conf file, and may need vhosts to be explicitly labelled with ServerName or ServerAlias directories. Falling back to default vhost *:443…

It turns out that Certbot doesn’t like HTTP and HTTPS configurations being lumped into one .conf file. Instead it expects to see all the port 80 stuff in a domain.com.conf file, and the port 443 stuff in a domain.com-ssl.conf file.

So I’ve taken that original .conf file and split it up into two.

First I SSH’d into my server and went to the Apache directory where all these .conf files live:

cd /etc/apache2/sites-available

Then I copied the current (single) file to make the SSL version:

cp yourdomain.com.conf yourdomain.com-ssl.conf

Time to fire up one of those weird text editors to edit that newly-created file:

nano yourdomain.com-ssl.conf

I deleted everything related to port 80—all the stuff between (and including) the VirtualHost *:80 tags:

<VirtualHost *:80>
...
</VirtualHost>

Hit ctrl and o, press enter in response to the prompt, and then hit ctrl and x.

Now I do the opposite for the original file:

nano yourdomain.com.conf

Delete everything related to VirtualHost *:443:

<VirtualHost *:443>
...
</VirtualHost>

Once again, I hit ctrl and o, press enter in response to the prompt, and then hit ctrl and x.

Now I need to tell Apache about the new .conf file:

a2ensite yourdomain.com-ssl.conf

I’m told that’s cool and all, but that I need to restart Apache for the changes to take effect:

service apache2 restart

Now when I test the certificate renewing process…

/etc/certbot-auto renew --dry-run

…everything goes according to plan.

Wednesday, November 30th, 2016

The Guardian has moved to https 🔒 | Info | The Guardian

Details of The Guardian’s switch to HTTPS.

Friday, November 25th, 2016

Hey designers, if you only know one thing about JavaScript, this is what I would recommend | CSS-Tricks

This is a really great short explanation by Chris. I think it shows that the really power of JavaScript in the browser isn’t so much the language itself, but the DOM—the glue that ties the JavaScript to the HTML.

It reminds me of the old jQuery philosophy: find something and do stuff to it.

Thursday, July 21st, 2016

HTTPS Adoption *doubled* this year

Slowly but surely the web is switching over to HTTPS. The past year shows a two to threefold increase.

Sunday, May 29th, 2016

Switching to HTTPS on Apache 2.4.7 on Ubuntu 14.04 on Digital Ocean

I’ve been updating my book sites over to HTTPS:

They’re all hosted on the same (virtual) box as adactio.com—Ubuntu 14.04 running Apache 2.4.7 on Digital Ocean. If you’ve got a similar configuration, this might be useful for you.

First off, I’m using Let’s Encrypt. Except I’m not. It’s called Certbot now (I’m not entirely sure why).

I installed the Let’s Encertbot client with this incantation (which, like everything else here, will need root-level access so if none of these work, retry using sudo in front of the commands):

wget https://dl.eff.org/certbot-auto
chmod a+x certbot-auto

Seems like a good idea to put that certbot-auto thingy into a directory like /etc:

mv certbot-auto /etc

Rather than have Certbot generate conf files for me, I’m just going to have it generate the certificates. Here’s how I’d generate a certificate for yourdomain.com:

/etc/certbot-auto --apache certonly -d yourdomain.com

The first time you do this, it’ll need to fetch a bunch of dependencies and it’ll ask you for an email address for future reference (should anything ever go screwy). For subsequent domains, the process will be much quicker.

The result of this will be a bunch of generated certificates that live here:

  • /etc/letsencrypt/live/yourdomain.com/cert.pem
  • /etc/letsencrypt/live/yourdomain.com/chain.pem
  • /etc/letsencrypt/live/yourdomain.com/privkey.pem
  • /etc/letsencrypt/live/yourdomain.com/fullchain.pem

Now you’ll need to configure your Apache gubbins. Head on over to…

cd /etc/apache2/sites-available

If you only have one domain on your server, you can just edit default.ssl.conf. I prefer to have separate conf files for each domain.

Time to fire up an incomprehensible text editor.

nano yourdomain.com.conf

There’s a great SSL Configuration Generator from Mozilla to help you figure out what to put in this file. Following the suggested configuration for my server (assuming I want maximum backward-compatibility), here’s what I put in.

Make sure you update the /path/to/yourdomain.com part—you probably want a directory somewhere in /var/www or wherever your website’s files are sitting.

To exit the infernal text editor, hit ctrl and o, press enter in response to the prompt, and then hit ctrl and x.

If the yourdomain.com.conf didn’t previously exist, you’ll need to enable the configuration by running:

a2ensite yourdomain.com

Time to restart Apache. Fingers crossed…

service apache2 restart

If that worked, you should be able to go to https://yourdomain.com and see a lovely shiny padlock in the address bar.

Assuming that worked, everything is awesome! …for 90 days. After that, your certificates will expire and you’ll be left with a broken website.

Not to worry. You can update your certificates at any time. Test for yourself by doing a dry run:

/etc/certbot-auto renew --dry-run

You should see a message saying:

Processing /etc/letsencrypt/renewal/yourdomain.com.conf

And then, after a while:

** DRY RUN: simulating 'certbot renew' close to cert expiry
** (The test certificates below have not been saved.)
Congratulations, all renewals succeeded.

You could set yourself a calendar reminder to do the renewal (without the --dry-run bit) every few months. Or you could tell your server’s computer to do it by using a cron job. It’s not nearly as rude as it sounds.

You can fire up and edit your list of cron tasks with this command:

crontab -e

This tells the machine to run the renewal task at quarter past six every evening and log any results:

15 18 * * * /etc/certbot-auto renew --quiet >> /var/log/certbot-renew.log

(Don’t worry: it won’t actually generate new certificates unless the current ones are getting close to expiration.) Leave the cronrab editor by doing the ctrl o, enter, ctrl x dance.

Hopefully, there’s nothing more for you to do. I say “hopefully” because I won’t know for sure myself for another 90 days, at which point I’ll find out whether anything’s on fire.

If you have other domains you want to secure, repeat the process by running:

/etc/certbot-auto --apache certonly -d yourotherdomain.com

And then creating/editing /etc/apache2/sites-available/yourotherdomain.com.conf accordingly.

I found these useful when I was going through this process:

That last one is good if you like the warm glow of accomplishment that comes with getting a good grade:

For extra credit, you can run your site through securityheaders.io to harden your headers. Again, not as rude as it sounds.

You know, I probably should have said this at the start of this post, but I should clarify that any advice I’ve given here should be taken with a huge pinch of salt—I have little to no idea what I’m doing. I’m not responsible for any flame-bursting-into that may occur. It’s probably a good idea to back everything up before even starting to do this.

Yeah, I definitely should’ve mentioned that at the start.

Saturday, May 14th, 2016

Certbot

For your information, the Let’s Encrypt client is now called Certbot for some reason.

Carry on.

Monday, April 25th, 2016

Adding HTTPS to your web site - Robert’s talk

Robert walks through the process he went through to get HTTPS up and running on his Media Temple site.

If you have any experience of switching to HTTPS, please, please share it.

Friday, April 1st, 2016

HTTPS is Hard – The Yell Blog

Finally! An article about moving to HTTPS that isn’t simply saying “Hey, it’s easy and everyone should do it!” This case study says “Hey, it’s hard …and everyone should do it.”

Thursday, February 4th, 2016

Generate Mozilla Security Recommended Web Server Configuration Files

This is useful if you’re making the switch to HTTPS: choose your web server software and version to generate a configuration file.

Friday, January 22nd, 2016

New – AWS Certificate Manager – Deploy SSL/TLS-Based Apps on AWS | AWS Official Blog

If you’re hosting with Amazon, you now get HTTPS for free.

Tuesday, January 5th, 2016

Installing Letsencrypt on Ubuntu 14.04 and nginx | gablaxian.com

If you’re planning the move to TLS and your server is on Digital Ocean running Nginx, Graham’s here to run you through the (surprisingly simple) process.

Sunday, December 6th, 2015

Taking Let’s Encrypt for a Spin - TimKadlec.com

Tim outlines the process for getting up and running with HTTPS using Let’s Encrypt. Looks like it’s pretty straightforward, which is very, very good news.

I’m using the Salter Cane site as a test ground for this. I was able to get everything installed fairly easily. The tricky thing will be having some kind of renewal reminder—the certificates expire after three months.

Still, all the signs are good that HTTPS is about to get a lot less painful.

Monday, September 14th, 2015

More Proof We Don’t Control Our Web Pages, From the Notebook of Aaron Gustafson

Aaron collects some recent examples that demonstrate

  1. why we should use HTTPS and
  2. why we should use progressive enhancement.