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waxwing
npub1vadc...nuu7
Bitcoin, cryptography, Joinmarket etc.
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waxwing 5 days ago
The "Whitehat? Bullshit, that's stealing" natural response isn't really justified. If you see this bug and you don't want every user to lose their money, you are somewhat ethically bound to confiscate it until the devs release a fix. You are thus making deployment of the fix 100x less dangerous (because the collateral is not exposed during the transition. (Hot take? I don't think so?)
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waxwing 5 days ago
it seems that the bug ultimately comes down to this line: " " . range proofs that hit the cache that is keyed to this hash, are counted as valid without checking. the problem is that the data fed into the hash is not length checked. so you can feed different (proof, commitment, asset) tuples into it by varying the length of the proof. the proof can be totally invalid and it'll still come back as valid. and this explains why OP_RETURN is involved: you need an extra output to sort of 'consume' the invalid amount. so you make a totally valid output of 4000 btc and you shove the negative corresponding value in the OP_RETURN. Apparently the anomalous size of the proof confirms this reading (bulletproofs rangeproofs have specific sizes based on the bit range 0..2^k). The only part I don't get is why there was a consensus deviation. Did some nodes have the rangeproof caching disabled or something?
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waxwing 5 days ago
I think GLM 5.2 might have found this. See Poelstra's response in this github thread: . What if someone created a transaction with an OP_RETURN that has a pedersen commitment that has some big negative value? If it gets included in the balance equation, that can work *only if* the range proof is not attached to that output. See - this is the transaction at which people are saying there's a consensus split. View quoted note →
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waxwing 5 days ago
Liquid rolling back the chain in 3.. 2...
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waxwing 5 days ago
A little anti-doomer take for those of you (like me!) getting worried about AI. It's just a small niche but maybe the same thoughts could cross-apply to other areas of life: I don't think it's very likely that AI will find classical breaks (as in, poly-time algos) to ECDLP. That's just an offhand intuition, but it's a very deep mathematical problem (factoring, also, though I guess that one is a bit safer). While at the same time, consider some of the big-picture problems - not hardness problems, but things we want to do, but can't - like functional encryption, indistinguishability obfuscation, fully homomorphic encryption, post-quantum analogs that don't have horrible tradeoffs, in cryptography. It's orders of magnitude more likely that AI will find *very* good solutions to those kind of problems. If they do, it will mean that things like Bitcoin become vastly more powerful, because vastly more useful. And the one thing that really underpins Bitcoin is not susceptible to some vast intelligence changing its character: energy scarcity. if you unlock a 10x on how much energy humanity has access to, obviously that changes a ton of things, but it doesn't change that energy is scarce. it's the finiteness that matters in proof of work, not the number. so short version: much *better* cryptography meaning much better bitcoin usability, is actually a pretty likely outcome.
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waxwing 1 week ago
Why haven't people been working on arbitrarily complex contracts *inside* a Lightning channel? Think BitVM but without the ugliness of what's needed to make dispute resolution work non-interactively onchain. (Oh and btw we *do* have PTLC; anyone can deploy it in their own channel.)
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waxwing 1 week ago
You can bet signet coins at .. implementation of babilonia . need to use a psbt supporting wallet for signing, works with Sparrow and Core and should be taproot. Though i guess you could do it non-taproot but you need the psbt co-signing feature. paper and code are linked at the top of the page. This is just for demonstration purposes, the better way of doing it is p2p via a Core node, though this is perhaps more fun :)
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waxwing 1 week ago
blockstream.info/signet lowest priority fee: 4277 sats/vb. It's been drifting up. I guess something broke their end, I'm kind of curious what, though.
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waxwing 1 week ago
So suppose that some people out there were developing a protocol for private payments on bitcoin that required 800 byte OP_RETURNs per transaction. How would you feel about that?
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waxwing 1 week ago
Is there some nasty stuff going down? Protonmail was clearly having a big problem today, then I see news on twitter/X about email leaks? Nordvpn?
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waxwing 1 week ago
I love how they explain derisking here as if it's some obscure thing that they wouldn't have known in advance. They don't mention bitcoin. Why wouldn't something like autistici.org use bitcoin? (I mean, also tor, but they probably do use that?). I think there's a certain wilful ignorance about this stuff from a lot of 'activists'. If they're not even prepared to route around the banking system, how much of it is just LARPing.