Searching yarn

Twts matching #twtxt.
Sort by: Newest, Oldest, Most Relevant
In-reply-to » Does anybody know a right mouse click save and reduce a screen saver image to a smaller file, say 50KB? My usual method is slow, place in image program and re-save it smaller.

@off_grid_living@twtxt.net No right click thing, but in the terminal:

convert -strip -quality 70 -resize 300x original.jpg resized.jpg

“original.jpg” being the filename of the input file and “resized.jpg” the filename of the output. You can play around with the width, “300x” means 300 pixels wide and the height is determined automatically to still remain in the same ratio. The quality is how much to compress it. The closer to 0 the value gets, the worse the result, but also smaller in file size. More towards 100 and the quality improves together with a larger file size.

You have to install the package “imagemagick” for this to work, I believe.

⤋ Read More
In-reply-to » @eapl.me Here is what I've got so far: https://github.com/upputter/testing-twtxt-dm

here is my progress so far: https://github.com/eapl-gemugami/twtxt-direct-message-php
The encryption part seems to work, if I decrypt it the message with OpenSSL.
I think it can help you for some key parts not well explained in OpenSSL documentation.

@andros@twtxt.andros.dev reading your spec I wrote a few notes here: https://github.com/eapl-gemugami/twtxt-direct-message-php/blob/main/direct_message_spec.md

@arne@uplegger.eu I haven’t check your repo yet, although you are using sodium, right?

⤋ Read More
In-reply-to » @eapl.me Here is what I've got so far: https://github.com/upputter/testing-twtxt-dm

@arne@uplegger.eu Here are the results of the german jury:

Known salt (B64): Tb9oj07UhwU= (8)
Known key (B64): MII0yj+MC0mHNx254Voar80bi9P7jmocs0+x+inaxBE=
Known iv (B64): l/PvkDjOKMFZe73KptrvWw== (16)
Shared Key (B64): ql8zvN03p6kroSwNrcKbxk4zSBQFkgQZEumvqVIDMAE=
** DECRYPT **
Encrypted Message: ...
Decoded Salt (B64): Tb9oj07UhwU= (8)
PBKDF2 KEY (B64): MII0yj+MC0mHNx254Voar80bi9P7jmocs0+x+inaxBE=
iv (B64): JanbU1jI30lb6yfjq/adjA== (16)
Decrypted Message: 

😭

⤋ Read More
In-reply-to » trying to implement it quickly, I get the same questions than you ```

@eapl.me@eapl.me Here is what I’ve got so far: https://github.com/upputter/testing-twtxt-dm

There is a “00_well_known_message.enc” file, which I have the encryption paremters for (https://github.com/upputter/testing-twtxt-dm/blob/9fdf3be6aa8fe810a4cb275375dbb3d4a2a958ee/wellknown_test.php#L28).

According to my finding, I assume, that the saltsize in openssl is “8” and the PBKDF2 algo is “sha256”.

⤋ Read More
In-reply-to » Today is an important day. We have a new extension: Direct message 🪇🗨️🚀🥳❤️ https://twtxt.dev/exts/direct-message.html #twtxt

@andros@twtxt.andros.dev Could you share (perhaps in the extension document) the private key for alice?

I want to compare that I can read the encrypted message both from OpenSSL CLI and from the PHP OpenSSL library, following the spec.

⤋ Read More
In-reply-to » @arne Well, just for my understanding. The command: echo "Lorem ipsum" | openssl enc -aes-256-cbc -pbkdf2 -iter 100000 -out message.enc -pass file:shared_key.bin will take the input string from echo to openssl. It then will

@arne@uplegger.eu With the OpenSSL option -p one can get an output of salt, key and iv. My stupid PHP-code can get everything right from the encrypted data (from OpenSSL) - except the iv! Damn “evpKDF” 😔

⤋ Read More
In-reply-to » Today is an important day. We have a new extension: Direct message 🪇🗨️🚀🥳❤️ https://twtxt.dev/exts/direct-message.html #twtxt

@arne@uplegger.eu Hi! I love that you’re implementing it! Maybe, when we’re both done, we could test the clients by communicating both.
I don’t think I’m going to be able to help you much, my knowledge of OpenSSL and PHP is not as high as I’d like it to be.
Maybe the OpenSSL version uses SHA-1 by default in PHP. Or that the IV is derived together with the key (not generated separately). But I’m not able to answer your questions, sorry.
I’m invoking the commands directly, without any libraries in between. Maybe that would help you?

⤋ Read More
In-reply-to » @andros I have really tried to get behind it. For an implementation for my TwtxtReader (PHP) I simply lack the knowledge of the standard-openssl parameters. All my solution approaches require “nonce” or “initialization vector” on one or the other side. In addition, the “magic numbers” (“Salted__”) were not consistent in my tests.

@arne@uplegger.eu Well, just for my understanding. The command:
echo "Lorem ipsum" | openssl enc -aes-256-cbc -pbkdf2 -iter 100000 -out message.enc -pass file:shared_key.bin
will take the input string from echo to openssl. It then will

  1. use the content of shared_key.bin as password
  2. use PBKDF2 with an iteration of 100000 to generate a encryption key from the given password (shared_key.bin)
  3. use the PBKDF2 generated key for an aes-256-cbc encryption

The final result is encrypted data with the prepended salt (which was generated by runtime), e.g.: Salted__q�;��-�T���"h%��5�� ....

With a dummy script I now can generate a valide shared key within PHP ‘openssl_pkey_derive()’ - identical to OpenSSL.
I also can en-/decrypt salted data within my script, but not with OpenSSL. There are several parameters of PBKDF2 unknown to me.

Question:

  1. Is the salt, used by aes-256-cbc and PBKDF2 the same, prepended in the encrypted data?
  2. Witch algorithm/cipher is used within PBKDF2: sha1, sha256, …?
  3. What is the desired key length of PBKDF2 (https://www.php.net/manual/en/function.openssl-pbkdf2.php)?

To be continued …

⤋ Read More
In-reply-to » @andros I have really tried to get behind it. For an implementation for my TwtxtReader (PHP) I simply lack the knowledge of the standard-openssl parameters. All my solution approaches require “nonce” or “initialization vector” on one or the other side. In addition, the “magic numbers” (“Salted__”) were not consistent in my tests.

@arne@uplegger.eu current progress If I keep the “nonce”, I can decrypt a message with the shared key, like in the direct message specs.
But that is not how it should work. 😒

⤋ Read More
In-reply-to » Today is an important day. We have a new extension: Direct message 🪇🗨️🚀🥳❤️ https://twtxt.dev/exts/direct-message.html #twtxt

@andros@twtxt.andros.dev I have really tried to get behind it. For an implementation for my TwtxtReader (PHP) I simply lack the knowledge of the standard-openssl parameters.
All my solution approaches require “nonce” or “initialization vector” on one or the other side. In addition, the “magic numbers” (“Salted__”) were not consistent in my tests.

⤋ Read More
In-reply-to » 💭 Remember kids 🧒

@prologic@twtxt.net I wish getting a static IP and a (more) stable internet connection wasn’t so hard over here. Then I could do proper self-hosting as well. But as it stands, I need some rented VPS.

I could go ahead and just use the VPS for the IP, i.e. forward all traffic through Wireguard to a box here at home. Big downside is that the network connection would be even slower than it already is and my ISP breaks down all the time for a few minutes … it’s just bad overall and much easier/better to rent a VPS. 🫤

⤋ Read More
In-reply-to » I'm in an article in Quanta Magazine! It's about the bizarre world of algorithms that re-use memory that's already full. https://www.quantamagazine.org/catalytic-computing-taps-the-full-power-of-a-full-hard-drive-20250218/ I'm the one with all the snow in the background.

Thanks, @falsifian@www.falsifian.org! I’ll definitely start with the latter one then. Let’s see how far I make it. :-)

⤋ Read More
In-reply-to » I got promoted today to try using Passkeys on Github.com. Fine 😅 I did that, but I discovered that when you use your Passkey to login, Chrome prompts you for your device's password (i.e: The password you use to login to your macOS Desktop). Is that intentional? Kind of defeats the point no? I mean sure, now there's no Password being transmitted, stored or presented to Github.com but still, all an attacker has to do is somehow be on my device and know my login password to my device right? Is that better or worse? 🤔

@prologic@twtxt.net I’m speculating, but if I had to guess I’d say it’s probably asking for your user password in order to access some user keyring (or whatever your OS uses to manage user secret credentials) used to safely store your passkeys related data in order to do its passkeys /ME doing air quotes Magic™ … you could try with a different password manager to avoid said scenario.

Also, passkeys UX sucks.

⤋ Read More
In-reply-to » I'm in an article in Quanta Magazine! It's about the bizarre world of algorithms that re-use memory that's already full. https://www.quantamagazine.org/catalytic-computing-taps-the-full-power-of-a-full-hard-drive-20250218/ I'm the one with all the snow in the background.

@lyse@lyse.isobeef.org I am a big fan of “obvious” math facts that turn out to be wrong. If you want to understand how reusing space actually works, you are mostly stuck reading complexity theory papers right now. Ian wrote a good survey: https://iuuk.mff.cuni.cz/~iwmertz/papers/m23.reusing_space.pdf . It’s written for complexity theorists, but some of will make sense to programmers comfortable with math. Alternatively, I wrote an essay a few years ago explaining one technique, with (math-loving) programmers as the intended audience: https://www.falsifian.org/blog/2021/06/04/catalytic/ .

⤋ Read More
In-reply-to » I'm in an article in Quanta Magazine! It's about the bizarre world of algorithms that re-use memory that's already full. https://www.quantamagazine.org/catalytic-computing-taps-the-full-power-of-a-full-hard-drive-20250218/ I'm the one with all the snow in the background.

@falsifian@www.falsifian.org Oh, that’s neat! Interesting how “obviously” isn’t all that obvious at all, even to the contrary. I reckon I have to read up on that subject on the weekend. :-)

I like how Ian’s and your photo complement each other, winter and summer join forces for something special. :-)

⤋ Read More
In-reply-to » This twt is from an unknown or muted feed.

@movq@www.uninformativ.de @prologic@twtxt.net I don’t know, I don’t see this happening all that often. Very rarely. The problem I encounter much more often is that tech folks are blindly adopting every new hype without thinking the slightest bit what the consequences might be.

But maybe that also means I’m one of these “told you so” guys. Not sure.

⤋ Read More
In-reply-to » It would appear that Google's web crawlers are ignoring the robots.txt that I have on https://git.mills.io/robots.txt with content:

@prologic@twtxt.net Have you tried Google’s robots.txt report? https://support.google.com/webmasters/answer/6062598?hl=en . I would expect Google to be pretty good about this sort of thing. If you have the energy to dig into it and, for example, post on support.google.com, I’d be curious to hear what you find out.

⤋ Read More

Yesterday I was doing a lot of research on how #hyperdrive and the #holepunch project work. Would it be possible to use it to make #twtxt an easier gateway for new users? Could we stop using web servers?
My conclusion: We would end up being a #nostr. On the one hand it would become more complex to use, it would force the user to have software installed, and on the other hand the community would need a central proxy to make the routes accessible via HTTP. In other words, it’s not a good idea.
However, it’s an AMAZING technology. I want to start playing with it.

⤋ Read More