Replying to
@prettygood@socially.drinkingatmy.computer @japananon@mitra.anon-kenkai.com
Don't give the Japanese govt ideas on how to get more My Number cards issued.
Remote
Grey Area
@greyarea@mitra.vpclmulqdq.moe
mitra 5.10.0
脳を焼かれた独立傭兵
荒事と情報戦
Applied Cryptography/System Programming
You are cordially invited to a night at the opera.
荒事と情報戦
Applied Cryptography/System Programming
You are cordially invited to a night at the opera.
14 Followers
10 Following
27 Posts
Joined August 13, 2023
Replying to
@heavens_feel @BrokenSword
You're in Japan, you can buy the One True Keyboard series without the markup.
https://www.realforce.co.jp/products/series_r4.html
Ramsey Khalid Ismael (Johnny Somali)'s sentencing is tomorrow. Hopefully the Koreans do what the Japanese didn't (relatively likely), and throw him in the slammer.
草
Never change Japan.
草
https://www.youtube.com/watch?v=9xxK5yyecRo
Timely and relevant.
Afroman - Lemon Pound Cake (OFFICIAL MUSIC VIDEO)
Replying to
@heavens_feel
If you drink https://ryuguw.com/ is fun (esp when they have an event, check the schedule).
Pragmata (aka "Dad Space") is one of the best things AAA has done since AC6.
This fills my cold black heart with glee.
Japan peeps, while I typically do not go out to the Ikebukuro area, http://wonder-parlour.com/ (yes, no TLS because Japan), is pretty great as far as "maid cafes that function as cafes" goes.
But it's more "good tea/atmosphere" than my usual maid cafe, so "will visit again, but the Akihabara one probably will be my primary go to".
(Yes, the Maid Cafe that's oddly popular for tweeting in English recently.)
JSON (and variants) make baby Jesus cry. Unless you absolutely need it to be human readable without tools (though a one-line JSON blob hardly qualifies), for the love of god, use CBOR.
Replying to
@silverpill@mitra.social @sabrinkmann@hachyderm.io @grindhold@23.social
Floating point for currency is universally a bad idea.
in some the integer type has a relatively low maximum value (JavaScript?)
The built in arithmetic is all 64-bit floats. So error-free integer arithmetic is limited to 53 bits.
JSON (RFC 8259) is even worse since the definition of what a Number is does not specify a minimum precision/range ("This specification allows implementations to set limits on the range and precision of numbers accepted.") , though it does loosely recommend IEEE754 doubles (JavaScript).
Replying to
@silverpill@mitra.social @mkljczk@pl.fediverse.pl
That lead to a criminal case in Japan. Guilty, overturned on appeal.
https://www.asahi.com/ajw/articles/14527143
Replying to on mitra.social
@silverpill@mitra.social @raucao@kosmos.social @lain@lain.com @sozialwelten@ifwo.eu @koteisaev@mastodon.online
HPKE has the benefit of being standardized, and imperfect forward secrecy is the best you can do with 0-RTT (which probably fits the fediverse model better).
Just be very careful about the "use correctly" and it's "fine". I'm partial to Noise (https://noiseprotocol.org/) for these sort of use cases because it has less foot+guns and there's more flexibility, but I wouldn't freak out or scream if I saw HPKE in use.
As a side note, it is indeed safe to convert ed25519 keys to X25519 keys assuming a common sense step is taken when using the latter (https://eprint.iacr.org/2021/509)
Replying to
@silverpill@mitra.social @raucao@kosmos.social @lain@lain.com @sozialwelten@ifwo.eu @koteisaev@mastodon.online
WhatsApp.
It's biggest claim to fame is non-group messaging (WireGuard), and the fact that the designer based it on the Signal wire protocol design (same person). The latter research that adds concrete security proofs is an added bonus, as well as decent library availability.
But, there's only so many ways to do NIKE (Non-Interactive Key Exchange), and the IETF/IRTF has a preference for reusing their own standards.
TLDR: Noise over HPKE is a personal preference, I think it's harder to blow your foot off with Noise and it's easier to implement (having done multiple Noise impls, and dealt with HPKE more than I should), but honestly either is a reasonable choice, and if you want something more standardized, HPKE is reasonable.
Replying to
@silverpill@mitra.social
The primitive choices are sensible.
The "aad" is sent in the clear (or just public as it is now) so you could do something like "fep-0806-aad" | ':' | | ':' | |':' | . If the proof covers all of that then it's not strictly needed, but it's cheap paranoia.
I was going to say add version info to the labels, but fep0806:cipherAlgorithm covers that.
Replying to
@silverpill@mitra.social
Of an envelope. If actor being changed mid-transit isn't a problem, then omit it from the aad. Including the from/to as part of the AAD binds the ciphertext to the origin/recipient (the HPKE ciphertext does not carry any of this information).
It is worth noting that, as the FEP is specified now, using the sender and recipient's keypairs to do HPKE will result in the same shared secret being generated for every message. This is catastrophic to security as the nonce for the symmetric portion of the HPKE encryption is deterministic (RFC 9180 5.1).
This can be avoided by either: having the sender generate an ephemeral keypair (include the public key envelope), or using a unique HPKE info per envelope. The former is better as it gives imperfect forward secrecy (sender identity key compromise does not reveal past plaintexts), the latter is cheaper to do.
Replying to
@silverpill@mitra.social
No, the recipient would also generates an ephemeral key, and uses that when replying.
So it's always a one shot ephemeral (sender)/static (recipient) HPKE exchange, with sender authenticity guaranteed by the signature. Could also use the shared secret from the original post but force a different IV, but "replies are just the sender and receiver being flipped, code path is the same" is easier.
Replying to on mitra.social
@silverpill@mitra.social
Do you think it's worth doing this?
Identity hiding is a useful property (especially in the current environment), and simpler is better. Especially if the inner activity is self-authenticating.
ps: I should look more into the fediverse protocol, but from what I remember from peeking at it a long time ago it was a giant mess of w3c specs.
Replying to
@silverpill@mitra.social
Agreed on 1 and 2, and think that enabling identity obfuscation is a feature.
Replying to
@heavens_feel@poa.st
Someone should introduce him to the now bankrupt (and can't afford to sue), Spirit Airlines, along with the petabytes of bodycam footage.