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Michael Stapelberg
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Michael Stapelberg

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mind = blown: https://www.alchemistowl.org/pocorgtfo/pocorgtfo03.pdf

“Technical Note: This file, pocorgtfo03.pdf, complies with the PDF, JPEG, and ZIP file formats. When en-crypted with AES in CBC mode with an IV of 5B F0 15 E2 04 8C E3 D3 8C 3A 97 E7 8B 79 5B C1 and a key of “Manul Laphroaig!”, it becomes a valid PNG file. Treated as single-channel raw audio, 16-bit signed little-endian integer, at a sample rate of 22,050 Hz, it contains a 2400 baud AFSK transmission.”
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Michael Stapelberg

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So this is interesting (to TCP geeks).

+John Looney noticed that:

    while true; do telnet localhost 50000; done

will eventually succeed in connecting (nothing's listening on port 50000), and, strangely, it connects to itself. What's happening is that the ephemeral port allocated for the socket source is actually accepting the connection, resulting in a self connect.

You can make this happen immediately by specifying a source port; eg:

        socat stdio TCP:localhost:50000,sourceport=50000

Even more interestingly; if you have two machines, and arrange matters so that each connects to the other using the other's source address as their target address, the connection is established. This can be shown using socat as follows:

    On machine A: while true; do socat stdio TCP:B:50000,sourceport=50001; done
    On machine B: while true; do socat stdio TCP:A:50001,sourceport=50000; done

(The loop retries until we manage to hit the narrow window between connection attempt and reset on each system; I typically see about 40-50 attempts before success.)

+Kevin Lyda and +Paul Jakma did some further investigation, and it looks like this is how the "simultaneous connection synchronisation" of TCP works - see figure 8 of RFC793. General opinion of the systems administration people I've shown this to is "WITCHCRAFT!"

Your Interesting Network Thing Of The Day.

For your next task: figure out how to make this into a connection-interception hack. Easiest to achieve on localhost due to the size of the address:port space, but still...
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Michael Stapelberg

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SORTING - A visualization of the most famous sorting algorithms
http://sorting.at/
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Michael Stapelberg

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When assembling the last of four IKEA chairs, I found this bag of screws. There seems to be an anarchist trapped in an IKEA packing factory…? :)
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Michael Stapelberg

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So, C++ error messages are really bad, everyone knows that. But look at this: a competition to achieve the most horrible error message with the fewest characters possible :-D

http://tgceec.tumblr.com/post/74534916370/results-of-the-grand-c-error-explosion-competition
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Awesome!
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Michael Stapelberg

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I must share the pain. Specifically with +Stephen Shirley, +Kristian Köhntopp and +Fabian Schorp 
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Of course the Valentine’s Day decoration at our end-of-week social gathering was chosen appropriately for a company full of nerds, who tend to get sick of Valentine’s Day easily… (or any other excessively commercialized holiday) :-)
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Admit: You are only jealous because you don't have a girlfriend =þ
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Very usefully really. Thanks.


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Good food for a reasonable price. It took quite a bit (about 50 minutes) until our food arrived and the waitress forgot a coke, but overall we were treated quite friendly. I’d recommend this place if you’re not in a hurry :).
Public - 5 months ago
reviewed 5 months ago
Good burgers for an okay price (paid 35 CHF for a soft drink, fries, a swiss angus beef burger).
Public - 5 months ago
reviewed 5 months ago
Durchschnittliche Kneipe mit durchschnittlichem Essen. Nicht schlecht, aber auch nicht gut.
Food: GoodDecor: GoodService: Good
Public - 11 months ago
reviewed 11 months ago
We were welcomed warmly with personal greetings by the chef. The waitresses took our orders very efficiently (two people to handle our group of 20 people) and we were promptly served drinks and food. The portions are huge, which I really did not expect for the affordable price (29 CHF for a coke and a huge pizza, including tip). The food also tasted pretty good :-).
Food: Very goodDecor: GoodService: Very good
Public - 12 months ago
reviewed 12 months ago
16 reviews
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Dieses Restaurant ist aus einem multi-kulturellen Sozialprojekt hervorgegangen, als ausgesprochenes Motto ist hier jeder willkommen. Das Essen ist lecker und nicht zu teuer, die Bedienung freundlich, ehrlich und sympathisch, aber nicht immer so schnell und aufmerksam wie man das in Zürich gewöhnt ist.
Public - 5 months ago
reviewed 5 months ago
The service was excellent, we were treated very friendly. The food (Wiediker Bratwurst) was really good, too, and cost about 25 CHF.
Food: Very goodDecor: GoodService: Excellent
Public - 11 months ago
reviewed 11 months ago
The “Wiediker” sausage with potato salad tasted really good. Service was very friendly, fluent in German and English, and quick. We sat outside because it was too full inside, so I cannot really comment on the interior.
Food: Very goodDecor: GoodService: Excellent
Public - a year ago
reviewed a year ago