Terence Eden. He has a beard and is smiling.

Terence Eden’s Blog

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Disable JavaScript on Specific Sites using Firefox for Android and uBlock Origin

· 1 comment · 200 words · Viewed ~431 times


The my rules sub-page.

Sometimes, you want to stop scripts running only on specific domains. The best way to do that, I think, is with uBlock Origin - a free and fast ad-blocker. On the desktop version, it's simple to block scripts. Click the plugin icon, then click the disable scripts button. But on mobile it's a little more complicated. Here's how to do it on the Android version of Firefox. Install Firefox. Then …

DMCA as a vector for pornographic spam?

· 7 comments · 300 words · Viewed ~549 times


To: Webmaster of https://shkspr.mobi/, Google has been notified, according to the terms of the Digital Millennium Copyright Act (DMCA), that some of the material found on your site allegedly infringes upon the copyrights of others. We’re in the process of removing the allegedly unlawful materials from Google Search results. The notice that we received, with any personally identifying information removed, may be found on the website of Lumen, a third-party aggregator of legal complaint notices, at https://lumendatabase.org/notices/42788513.

There's a law in the USA called the DMCA - Digital Millennium Copyright Act. Amongst its myriad provisions is the ability for copyright holders to send takedown notices to service providers. If someone has ripped off your content, you can send them a legal letter saying "take that down". People often send DMCA requests to Google saying "this site has stolen my copyrighted content - please remove …

An end to daily blogging

· 13 comments · 250 words · Viewed ~270 times


Screenshot of a calendar of my daily blogging.

If you explore this blog's archives, you'll see that I've been blogging continuously every day since the start of 2020. Before that, I was blogging every month since mid-2008. Today, I am very hungover. Although I usually write a bunch of posts a few days and weeks in advance, I find myself looking at my publishing calendar and seeing it blissfully empty. Part of the reason I blog is that I…

Can time-travellers use TOTP codes?

· 4 comments · 350 words · Viewed ~361 times


A chunky wristwatch showing the time and a selection of 6 digit codes and their corresponding entities.

Imagine, just for a moment, you and your friends decide to travel in time. In order to make sure you can authenticate your communications with each other, you set up a shared Time-based One Time Password (TOTP). The TOTP algorithm uses a Hash-based Message Authentication Code (HMAC). The hash is calculated from a shared key and a time-based component. The key is a short string of characters.…

We've received a letter about you

· 1 comment · 300 words · Viewed ~436 times


Royal coat of arms of the UK. A lion and a unicorn.

This is a retropost. It was written in July 2021, but published after I had left the Civil Service. An MP has written to the Chancellor of the Duchy of Lancaster asking about some work our department is doing. This is all rather usual for Government business. In the letter, the MP mentions me. By name. This is decidedly unusual! Civil Servants at my level are anonymous, interchangeable cogs…

How random are TOTP codes?

· 5 comments · 350 words · Viewed ~8,043 times


Histogram of distributions. 8 is clearly higher than the rest.

I'm pretty sure that the 2FA codes generated by my bank's TOTP app have a bias towards the number 8 - because eight is an auspicious number. But is that just my stupid meaty brain noticing patterns where none exist? The TOTP algorithm uses HMAC, which in turn uses SHA-1. My aforementioned brain is not clever enough to understand how that works. Although bigger, meatier brains have assured me it …

Password Resets in an Age of MFA

· 3 comments · 100 words · Viewed ~342 times


A padlock engraved into a circuit board.

Recently, WordPress got in contact with me to say they suspect that my password was exposed in some sort of data breach. Well, it's a day ending with a "y" - so of course some scumbag has pilfered my digital identity. WordPress mandated that I change my password. But was that really necessary? Firstly, the password was uniquely generated by my password manager. It isn't re-used anywhere else.…