DNS-over-HTTPS Is The Wrong Partial Solution

October 21, 2019 by Maya Posch 51 Comments

Openness has been one of the defining characteristics of the Internet for as long as it has existed, with much of the traffic today still passed without any form of encryption. Most requests for HTML pages and associated content are in plain text, and the responses are returned in the same way, even though HTTPS has been around since 1994.

But sometimes there’s a need for security and/or privacy. While the encryption of internet traffic has become more widespread for online banking, shopping, the privacy-preserving aspect of many internet protocols hasn’t kept pace. In particular, when you look up a website’s IP address by hostname, the DNS request is almost always transmitted in plain text, allowing all the computers and ISPs along the way to determine what website you were browsing, even if you use HTTPS once the connection is made.

The idea of also encrypting DNS requests isn’t exactly new, with the first attempts starting in the early 2000s, in the form of DNSCrypt, DNS over TLS (DoT), and others. Mozilla, Google, and a few other large internet companies are pushing a new method to encrypt DNS requests: DNS over HTTPS (DoH).

DoH not only encrypts the DNS request, but it also serves it to a “normal” web server rather than a DNS server, making the DNS request traffic essentially indistinguishable from normal HTTPS. This is a double-edged sword. While it protects the DNS request itself, just as DNSCrypt or DoT do, it also makes it impossible for the folks in charge of security at large firms to monitor DNS spoofing and it moves the responsibility for a critical networking function from the operating system into an application. It also doesn’t do anything to hide the IP address of the website that you just looked up — you still go to visit it, after all.

And in comparison to DoT, DoH centralizes information about your browsing in a few companies: at the moment Cloudflare, who says they will throw your data away within 24 hours, and Google, who seems intent on retaining and monetizing every detail about everything you’ve ever thought about doing.

DNS and privacy are important topics, so we’re going to dig into the details here. Continue reading “DNS-over-HTTPS Is The Wrong Partial Solution” →

Worn Out EMMC Chips Are Crippling Older Teslas

October 17, 2019 by Tom Nardi 230 Comments

It should probably go without saying that the main reason most people buy an electric vehicle (EV) is because they want to reduce or eliminate their usage of gasoline. Even if you aren’t terribly concerned about your ecological footprint, the fact of the matter is that electricity prices are so low in many places that an electric vehicle is cheaper to operate than one which burns gas at $2.50+ USD a gallon.

Another advantage, at least in theory, is reduced overal maintenance cost. While a modern EV will of course be packed with sensors and complex onboard computer systems, the same could be said for nearly any internal combustion engine (ICE) car that rolled off the lot in the last decade as well. But mechanically, there’s a lot less that can go wrong on an EV. For the owner of an electric car, the days of oil changes, fouled spark plugs, and the looming threat of a blown head gasket are all in the rear-view mirror.

Unfortunately, it seems the rise of high-tech EVs is also ushering in a new era of unexpected failures and maintenance woes. Case in point, some owners of older model Teslas are finding they’re at risk of being stranded on the side of the road by a failure most of us would more likely associate with losing some documents or photos: a disk read error.

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RTFM: ADCs And DACs

October 16, 2019 by Ted Yapo 11 Comments

It’s tough to find a project these days that doesn’t use an analog-to-digital converter (ADC) or digital-to-analog converter (DAC) for something. Whether these converters come as built-in peripherals on a microcontroller, or as separate devices connected over SPI, I2C, or parallel buses, all these converters share some common attributes, and knowing how to read the specs on them can save you a lot of headaches when it comes to getting things working properly.

There are some key things to know about these devices, and the first time you try to navigate a datasheet on one, you may find yourself a bit confused. Let’s take a deep dive into the static (DC) properties of these converters — the AC performance is complex enough to warrant its own follow-up article.

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Pack Your Bags – Systemd Is Taking You To A New Home

October 16, 2019 by Sven Gregori 177 Comments

Home directories have been a fundamental part on any Unixy system since day one. They’re such a basic element, we usually don’t give them much thought. And why would we? From a low level point of view, whatever location $HOME is pointing to, is a directory just like any other of the countless ones you will find on the system — apart from maybe being located on its own disk partition. Home directories are so unspectacular in their nature, it wouldn’t usually cross anyone’s mind to even consider to change anything about them. And then there’s Lennart Poettering.

In case you’re not familiar with the name, he is the main developer behind the systemd init system, which has nowadays been adopted by the majority of Linux distributions as replacement for its oldschool, Unix-style init-system predecessors, essentially changing everything we knew about the system boot process. Not only did this change personally insult every single Perl-loving, Ken-Thompson-action-figure-owning grey beard, it engendered contempt towards systemd and Lennart himself that approaches Nickelback level. At this point, it probably doesn’t matter anymore what he does next, haters gonna hate. So who better than him to disrupt everything we know about home directories? Where you _live_?

Although, home directories are just one part of the equation that his latest creation — the systemd-homed project — is going to ~~make people hate him even more~~ tackle. The big picture is really more about the whole concept of user management as we know it, which sounds bold and scary, but which in its current state is also a lot more flawed than we might realize. So let’s have a look at what it’s all about, the motivation behind homed, the problems it’s going to both solve and raise, and how it’s maybe time to leave some outdated philosophies behind us.

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Hackaday Prize China Finalists Announced

October 15, 2019 by Jenny List 3 Comments

In the time since the Hackaday Prize was first run it has nurtured an astonishing array of projects from around the world, and brought to the fore some truly exceptional winners that have demonstrated world-changing possibilities. This year it has been extended to a new frontier with the launch of the Hackaday Prize China (Chinese language, here’s a Google Translate link), allowing engineers, makers, and inventors from that country to join the fun. We’re pleased to announce the finalists, from which a winner will be announced in Shenzhen, China on November 23^rd. If you’re in Shenzen area, you’re invited to attend the award ceremony!

All six of these final project entries have been translated into English to help share information about projects across the language barrier. On the left sidebar of each project page you can find a link back to the original Chinese language project entry. Each presents a fascinating look into what people in our global community can produce when they live at the source of the component supply chain. Among them are a healthy cross-section of projects which we’ll visit in no particular order. Let’s dig in and see what these are all about!

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The Final Days Of The Fire Lookouts

October 15, 2019 by Tom Nardi 72 Comments

For more than a century, the United States Forest Service has employed men and women to monitor vast swaths of wilderness from isolated lookout towers. Armed with little more than a pair of binoculars and a map, these lookouts served as an early warning system for combating wildfires. Eventually the towers would be equipped with radios, and later still a cellular or satellite connection to the Internet, but beyond that the job of fire lookout has changed little since the 1900s.

Like the lighthouse keepers of old, there’s a certain romance surrounding the fire lookouts. Sitting alone in their tower, the majority of their time is spent looking at a horizon they’ve memorized over years or even decades, carefully watching for the slightest whiff of smoke. The isolation has been a prison for some, and a paradise for others. Author Jack Kerouac spent the summer of 1956 in a lookout tower on Desolation Peak in Washington state, an experience which he wrote about in several works including Desolation Angels.

But slowly, in a change completely imperceptible to the public, the era of the fire lookouts has been drawing to a close. As technology improves, the idea of perching a human on top of a tall tower for months on end seems increasingly archaic. Many are staunchly opposed to the idea of automation replacing human workers, but in the case of the fire lookouts, it’s difficult to argue against it. Computer vision offers an unwavering eye that can detect even the smallest column of smoke amongst acres of woodland, while drones equipped with GPS can pinpoint its location and make on-site assessments without risk to human life.

At one point, the United States Forest Service operated more than 5,000 permanent fire lookout towers, but today that number has dwindled into the hundreds. As this niche job fades even farther into obscurity, let’s take a look at the fire lookout’s most famous tool, and the modern technology poised to replace it.

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Tools, You Can’t Take Them With You

October 10, 2019 by Jenny List 91 Comments

When I die I hope be buried in the English rural churchyard that has been my responsibility as churchwarden, after a funeral service that has been a celebration of my life. I am neither an Egyptian pharaoh nor a Viking queen though, so my grave will not contain all my tools and equipment to serve me in the afterlife. Instead aside from my mortal remains it will contain only a suitably biodegradable coffin, and my headstone will be a modest one bearing perhaps a technical puzzle to entertain visitors to the churchyard.

My workshop, my bench, and my tools will be the responsibility of my nearest and dearest, and I hope I will have suitably equipped them for the task of their dispersal. But for anyone who has a sizeable collection of gear, have you thought of what would happen if someone else had to clean it all out? What is profession for some and hobby for others, we deal in specialization that might as well be tools of arcane magic to the uninitiated.

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