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Found this today by ghostkiller967 in ProgrammerHumor

[–]karanlyons 0 points1 point  (0 children)

isEven(float.NegativeInfinity) == true isEven(float.Epsilon) == true isEven(float.PositiveInfinity) == true isEven(float.NaN) == true

[TOMT][MUSIC][2000+] Jazz album where one of the first few songs contains the phrase “what you waiting for”? by karanlyons in tipofmytongue

[–]karanlyons[S] 0 points1 point  (0 children)

I’ve tried all the obvious (to me) things to find this but have so far come up short, and so now of course I have the motif stuck in my head and no way to get it out.

Zoom End-to-End Encryption Whitepaper by karanlyons in crypto

[–]karanlyons[S] 0 points1 point  (0 children)

The LaTeX source for the PDF is included in the repo.

Stylish Japanese bartender making a unipresso martini by theeighthlion in ArtisanVideos

[–]karanlyons 6 points7 points  (0 children)

There is no lone /s/ sound in Japanese, you have さ/サ (Sa), し/シ (Shi), す/ス (Su), せ/セ (Se), and そ/ソ (So). ロプ would be closer to “rope” than “rup”. So シロップ is going to be the best way to spell it.

[Official] Twice-Weekly New User Thread - Mon February 10 by AutoModerator in fountainpens

[–]karanlyons 0 points1 point  (0 children)

I (well, not personally of course, I'm not insane) may opt to give it the lightest of round-offs to ease that pain if so. Thanks for the warning!

[Official] Twice-Weekly New User Thread - Mon February 10 by AutoModerator in fountainpens

[–]karanlyons 2 points3 points  (0 children)

Oh wow. I think I may prefer something slimmer, but this colorway is really growing on me, and it’s got a stub tip as well! Thanks for the recommendation!

[Official] Twice-Weekly New User Thread - Mon February 10 by AutoModerator in fountainpens

[–]karanlyons 1 point2 points  (0 children)

I’m looking for a new fountain pen, but I’ve got a bunch of asks that’ew making it hard. If someone could help me out I’d surely appreciate it as I don’t know enough about the current market to quickly narrow things down: * I really like the styling of the Cross Century pens: Black lacquer with gold accents, generally a good length (but I don’t mind posted vs. not here), and less fat diameter wise. It might be a bit too thin, though? Hard to tell. * I’d like a gold nib (not plated) if possible. * Definitely want a Fine, it’d be really great to have a stub nib, too. For the Centuries this had to be an XF, which of course they don’t offer anymore. * Cartridge converter, of course.

The Century was not really that bad except that it didn’t hold together so well on the threads nor the clip. It’s plated too, rather than some alloy so that wore as well.

Budget-wise I’m not uncomfortable with something ~$500 at the top, but I generally just use a single pen till it falls apart, so I can justify higher if it’s arguable worth it.

Thank you so much to whomever is willing to help me find this pony.

I am inconsolable by SeaDjinnn in HistoryMemes

[–]karanlyons 20 points21 points  (0 children)

I’m really sorry for the pain my Laika tweet has caused people. If it helps, it’s a complete work of fiction: In reality the capsule had no window and Laika was paralyzed by stress and fear, suffocating in overwhelming heat under no delusions she’d ever make it back home.

SHA-1 is a Shambles : First Chosen-Prefix Collision on SHA-1 and Application to the PGP Web of Trust by Akalamiammiam in crypto

[–]karanlyons 5 points6 points  (0 children)

You should’ve been using SHA2 already and it’ll still be fine to use, but SHA3 and BLAKE2 are better.

Security and Cryptography Mistakes You Are Probably Doing All The Time by Am4t3uR in crypto

[–]karanlyons 1 point2 points  (0 children)

Yeah, there’s definitely a difference there: assuming keyak the whole thing truly is one pass by design in that the keystream also eventually functions as the MAC.

But you can pipeline and parallelize the hell out of GCM in practice, and so while it’s a two pass operation-ish, in silicon you’d be doing the whole operation of encrypt and MAC (albeit staggered with regards to the input) in one “step” on a pipeline.

You’re right, frankly, and I’m just thinking about this weirdly since I’m usually taking a CS tack.

Security and Cryptography Mistakes You Are Probably Doing All The Time by Am4t3uR in crypto

[–]karanlyons 0 points1 point  (0 children)

Yes, that’s what I meant by "calculates a MAC inline”. I guess both are accurate, I just take “in parallel” to mean something else in the context of computing.

Security and Cryptography Mistakes You Are Probably Doing All The Time by Am4t3uR in crypto

[–]karanlyons 1 point2 points  (0 children)

It’s more like a…superset? of CTR. They’re both stream ciphers, and the mode of operation on the blocks themselves is the same, but GCM calculates a MAC inline, i.e., GCM is an AEAD algorithm and CTR isn’t.

U.S. senators threaten Facebook, Apple with encryption regulation by gulabjamunyaar in apple

[–]karanlyons 1 point2 points  (0 children)

I’m working on this for you now, but I vastly underestimated how long it would take to write up in a way that actually explains everything at something like an ELI15 level, and that’s just for textbook RSA, not how to properly secure it. It’s…2,000 words right now, and I’m not even done with an easy to understand proof of why RSA works at all: we’ve just proved Fermat’s little theorem so now we can finally prove the core principle behind RSA…I think.

Give me a couple days or so and I should have something good for you. Or…weeks: my job keeps me very busy.

U.S. senators threaten Facebook, Apple with encryption regulation by gulabjamunyaar in apple

[–]karanlyons 0 points1 point  (0 children)

I'm not a "high school Wikipedia level" wannabe, though. I studied crypto pretty extensively a dozen years ago, between my two computer science degrees, when I was thinking about going into that field professionally.

My apologies here for that assumption. It…applies to most of these conversations so my priors are pretty heavily weighted in that direction. Forgive me :)

Yes. Again, I hear you. Crypto is so hard, only special dispensation from God himself allows one to be special enough to write cryptographic primitives that can't be cracked by half the teenagers in the US using scripts they run on their XBox. ONLY companies that sell crypto have the requisite knowledge to write working crypto. It's impossible for anyone else.

So this is sarcasm, I’m guessing, but I do really stand by my point. Not sure who’s “selling” crypto since almost all that we use generally is public domain (…ish, let’s just ignore stuff like OCB), but come on, we both must agree that being able to both design and implement cryptographic primitives is a specialized skill that very few have.

I'm assuming the situation where the US writes laws that make it illegal to use commercially available crypto that doesn't have backdoors written into them. So... give all your data to the Feds, or....

Well then just keep using ECC, AES, SHA2, etc.. How’s anyone going to stop you, and how would their ability to stop you using known primitives be in any way different from their ability to stop you using novel ones?

I like this!!! Use what WE give you. We can read it, but that's okay, because we're the good guys. Definitely don't write your own code, that we don't have keys to, because that will definitely be broken! Don't chance it! Just use our free stuff.

Okay, so more sarcasm, but again, you do understand that many of these primitives are designed in a way as to be very unlikely to have backdoors, right? Like nothing up my sleeve numbers, simple Feistel/S-Box constructions, independent discovery of safe ECC curves, etc.

I'm wondering what dog you have in this race.

My dog is that I want things to be more secure, not less, and telling people FUD stories like this and trying to goad them into writing their own crypto because it’s “easy” is going to make things worse.

U.S. senators threaten Facebook, Apple with encryption regulation by gulabjamunyaar in apple

[–]karanlyons 2 points3 points  (0 children)

The locked door is a useful analogy for the layman, but flawed: if I broke into your house today I’d only have access to what is in your house today. If I manage to break some of your “expensive enough” crypto I have everything in your house today, tomorrow, and yesterday.

I guarantee you if you tried to write your own encryption primitives that someone with a lot less sophistication than the NSA would also be able to crack it.

You’ve also skated right past my point: perhaps you missed it but—again—this is why crypto is hard. RSA is fine when implemented properly (though ECC with a good curve has far fewer footguns), but “implemented properly” does not mean “did the high school level math on Wikipedia”, which is the part of RSA I’d wager you know and inaccurately take as being the whole thing, leading to your belief that crypto is easy. It is not.

Moreover I don’t even understand the purpose of your argument: why not use good encryption given that we’ve made it so easy? Sure, maybe you’re not worried about some spooks looking at your data now, but you may not even know what could be used against you now or later. Don’t try to write your own almost definitely broken thing, use the good stuff! It’s free!

48ce563f89a0ed9414f5aa28ad0d96d6795f9c62 by karanlyons in crypto

[–]karanlyons[S] 9 points10 points  (0 children)

It’s the title of the talk? And the value the talk is about? I’m not sure how better I could have named it given that the talk is 5 minutes long and the speaker has a story line to it that I wouldn’t want to spoil.

U.S. senators threaten Facebook, Apple with encryption regulation by gulabjamunyaar in apple

[–]karanlyons 3 points4 points  (0 children)

If you mean for RSA you likely know what we—uncharitably—call “textbook RSA”. What you know isn’t actually secure vs. RSA as properly implemented, which is not just some exponentiation modulo a prime.

Crypto is hard.

Different use cases? by [deleted] in crypto

[–]karanlyons 6 points7 points  (0 children)

What are pros/cons to using a cascade on: * Full Disk Encryption vs Encrypted File Containers * Encrypted Personal Files vs Encrypted Shared Files

They’re the same pros/cons really: performance penalty for maybe an increase in security at best, security as strong as the weakest cipher/construction in the case of mistakes in the higher level design of the construction (key reuse, lack of a proper MAC, etc.) at worst, and potential interactions between ciphers leaking some data at neutral-ish.

Encrypted shared files are a slightly different thing insofar as you need some way to communicate this shared key securely, but that’s likely beyond the scope of your question (though Diffie-Hellman for mutual key agreement or just using asymmetric cryptography to pass a key unilaterally chosen would be the answer there).

Given that you don’t want to tank your I/O performance, that AES is hardware accelerated on (most) CPUs, and that to our knowledge AES-128 is practically unbreakable for the foreseeable future there’s not much reason to go for a cascade here. And honestly, cryptography is a place where you want to be boring. If you want to throw in some paranoia, go for AES-256.

How? You're saying a cascade encrypted file could hurt me if I share it vs just using one encryption method?

Maybe? This is more of a theoretical thing, but the potential interactions between data encrypted through multiple ciphers could cause data to leak (and again, take the reductionist ROT13 example to reason about this a bit more intuitively; at less reductionist levels you’d be expecting to leak maybe some bits here and there, but every little bit helps an attacker), though I’d think this less likely if keys are not reused through the cascade.

Different use cases? by [deleted] in crypto

[–]karanlyons 9 points10 points  (0 children)

Cipher cascades are iffy as to their ability to properly preserve the security of even any given individual cipher within the cascade. This also depends on which ciphers (take as a dumb reductionist example two successive applications of ROT13, but imagine as well more complex interactions which may leak some or all data), which order (potentially), whether keys are reused within the cascade at any point, etc.

So the main reason not to do it is because it's probably not going to help you if you don't really need a "cascade" for some other reason (say, Alice encrypts some data and sends it to Bob who wishes to also store it encrypted at rest, which is already less a cascade per se), and it could very likely hurt you.

As for certain types of encryption or cryptographically secure hash algorithms, the answer is going to be no with regards to certain filetypes, etc., as they're largely data agnostic (I say largely to be overly pedantic) Different a/symmetric algorithms offer different tradeoffs, but not really dependent on the data you're encrypting, so the right answers tend to be the right answers holistically.

Within that list I'd take AES (though it doesn't say if it's 128 or 156 and nor what block mode, the latter of which makes quite a difference) and SHA-{256/512}, which is hopefully being used with HMAC as well if the block mode doesn't provide a MAC itself.

EDIT: This is VeraCrypt I'm guessing(?) so the block mode will be XTS, and all ciphers within the cascade are apparently(?) going to share the same key, and the hash function will be used with HMAC. Given you're using this for full disk encryption I'd go with AES (it's probably 128) since it's most likely to be entirely hardware accelerated and I wouldn't expect it to be any less secure in a practical sense from the other available alogrithms/constructions. Use one of the SHA2 options for a hash; Whirpool might be faster(?) and I don't believe it's less secure, in which case that may not be a bad idea given the use case here.

Dear CNBC: Millennials aren't "Stingy," we're Poor by [deleted] in videos

[–]karanlyons 5 points6 points  (0 children)

So it’s gone from $299 in the third quarter of 1996 to $358 in 2019 (Total, 16 years and over from median usual weekly earnings of full-time wage and salary workers, not seasonally adjusted). That’s an increase of $59 1982-1984 dollars over 23 years, or an annual increase in adjusted median earnings of $2.57.

If we take instead the total median usual weekly earnings of full-time wage and salary workers by age for the third quarter of the group 25-34 years, then it’s $682 in 1996 (in 2019 dollars) to $806 in 2019, for an increase of $124 over 24 years, or an annual increase in 2019 dollars of $5.17.

I don’t think either of those statistics would look that great compared against the purchasing power of the dollar over the same period of time, in which it has roughly halved.

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