Viewing profile — daira

> BLAKE3 appears to have 128 bits of security against all attacks. That's not accurate. The best pseudo-preimage attack on BLAKE2s has complexity 2^{253.8} against 6.75 rounds (sec…

There's a pretty detailed proposal of a privacy-preserving L2 solution for Zcash, called BOLT ( https://z.cash/blog/bolt-private-payment-channels/ ). The original paper is at https…

Disabling SharedArrayBuffer is just stopping the most obvious method of exploitation; it's by no means a fix. Expect a slew of papers over the next few years on other methods of ex…

But you don't detect that one case where you are actually compromised. You dismiss it like you do all the false positives. At best, when you get pwned you think back to having dism…

The legacy codebase issue we are lamenting there is just that the code inherited from Bitcoin is in C++. It's of course possible to interface between C++ and Rust, and that's what …

As far as I know we've never claimed that the distribution is flat or that the "effective anonymity" is equivalent to a uniform distribution over prior notes (I certainly didn't cl…

Note that the number of prior shielded transactions (not the proportion, and not the value) is what is actually relevant to the privacy of new shielded transactions. Roughly speaki…

This bug had nothing to do with Zcash. Please correct your comment to say Zcoin, if that's what you meant. In any case, Zcash is also derived from Bitcoin and builds with `-Werror`…

Zcash, for example, is built with `-Werror` (edit: not `-Wall`, but we're working on that). So this is absolutely feasible on a Bitcoin-derived codebase.

No, that is not the bug. See Ian Miers' comments.

I'm not aware of any proof that Borromean signatures, relied on by CT, are secure assuming only ECDLP. There is certainly no such proof in the paper https://github.com/Blockstream/…

This isn't a subtle or difficult-to-find case. It's a case of "why the heck would anyone write code like that, in any language, in the first place?" The only language-level abstrac…

Just to clarify, the code that was duplicated per denomination is not part of libzerocoin itself, it's in main.cpp. I'm not sure who wrote it; it may or may not have been part of t…

The crypto used in Confidential Transactions, or any implementation of it, does not only rely on ECDLP. There's plenty of scope for potential protocol or implementation errors. (Th…

There are ways to significantly reduce the cost of zk proof verification by batching (that are compatible with the existing Zcash protocol without a fork).

Fixed in Zcash 1.0.3. (They were always "working", despite the bugs that were recently fixed. You can see plenty of successful z-address transactions on the blockchain.)

The concern in that last sentence seems misplaced; there is no relation between proportion of monetary base held by an attacker, and proportion of mining power held by an attacker.…

Basically yes. Strictly speaking privacy also relies on assumptions about Curve25519 (with a Blake2b-based key derivation function) and ChaCha20, but those are standard and uncontr…

It's a bit more complicated than that. The main responsibility for implementing connection layer unlinkability lies with Tor (if you use Zcash over Tor, which we will aim to provid…

Of course they've had to pay. In the case of the investors, they've had to pay cash up-front to fund the development of Zcash. In the case of other shareholders of Zerocoin Electri…

I don't actually see any assertions on this thread by natdempk or tptacek claiming that TextSecure is "trustworthy" and/or "solid". Did I miss something? My own opinion is that bot…

The scopes had a great deal of overlap; although we (Least Authority) didn't consider the iOS client at all, the rest of iSec's audit has essentially the same scope as ours. The po…

Actually I strongly suggest reading these in conjunction with iSec's issues 12 through 16, because each team spotted some details that the other missed.

Findings iSEC-RFACC0114-1 and iSEC-RFACC0114-3. (2 out of the 17 vulnerabilities found by iSec, of varying severity.)

This issue (or one with very similar effect) was also found by the Least Authority audit: https://github.com/cryptocat/cryptocat/issues/607 (The 'issue E' that it references is htt…