Encrypted DNS and NTP = Deadlock
I recently found out the hard way that encrypted DNS can deadlock with NTP on embedded devices without a battery-backed clock.
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I recently found out the hard way that encrypted DNS can deadlock with NTP on embedded devices without a battery-backed clock.
Before we get started, fair warning: this is going to be a post about a fairly absurd (but non-trivial!) attack on cryptographic systems. But that’s ok, because it’s based on a fairly a…
Mike Kohn's music, software, and electronics projects.
You're probably reading this page because you've attempted to access some part of my blog (Wandering Thoughts) or CSpace , the wiki thing it's part of. Unfortunately you're using a browser version that my anti-crawler precautions consider suspicious, most often because it's too old (most often this applies to versions…
Useful old technologies: ASN.1
I hate HTTP reverse proxies and want my webapps to listen directly on port 443. How can I make this work in a world of IPv4 scarcity?
© 2025 Peter N. M. Hansteen Long rumored and eagerly anticipated by some, the fourth edition of The Book of PF is now available for ...
A Xerox Alto system on the East coast had Ethernet problems, so the owner sent me the Ethernet board to diagnose. (After restoring our Alto,...
This is the first post of a many planned to shed light on the various networking techniques eBPF makes available to a Linux network developer.
Warning. This whole series is not a simple HOWTO. This series is about how I run my mail server. I go through the configuration, line by line and explain. It’s not going to be a simple Copy/Paste to run your own mail server. You have been warned.
Some thoughts on security after ten years of qmail 1.0 Bernstein, 2007 I find security much more important than speed. We need invulnerable software systems, and we need them today, even if they ar…
For the last month, I’ve been using XMPP (using Snikket) for every call and chat between me and my wife Sandra, at least.
A comment on a Hacker News thread inspired me to contemplate why Mastodon is everything we loved about social media before…
For over a year, I’ve been investigating a strange issue with the internet in my apartment. I’m posting the details here in case someone more knowledgeable than me can solve the mystery. I live in graduate student housing with internet provided by the university campus. Usually things work reasonably well, with one…
We present a simple to use implementation of networking across ultrasonic frequencies, by making use of Gnuradio and a microphone and speakers. This allows you to use TCP/IP , UDP across an audio link.
Update 20151216: This quick post got far more attention than expected. I regret not mentioning that the leakage can easily be prevented via a setting. In practice the problem remains, users in general will have no idea about this being a relevant setting to change and will stay with the default. The best discussion on…
Oscar is on the web
Most users who use the internet today, are mostly focused on three protocols, HTTP, TLS, and DNS.
We've all been there, right? You debug something, you try telnet to see if a port is open, and now you're stuck in a telnet session.
Coding in Rust and others; making coding videos.
Transport Layer Security (TLS) is the protocol involved in getting the lock icon to appear in your browser next to the URL. Under the hood it uses a bunch of really cool numbers for encryption. Some numbers are considered private and need securing; some are considered public and are fine for sharing. You can mix your…
The files mentioned in this article are available for viewing or cloning here: the 'pf-bedtime' repo .
The NY Times has a post up this morning about a neighborhood in Brooklyn called Red Hook where they have built a hyperlocal mesh network to service the entire neighborhood, from housing projects to townhouses. Red Hook is a cool place. We were there last night to sample Hometown Bar-B-Que‘s massive beef ribs and a […]
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