19:00:17 <achow101> #startmeeting 19:00:17 <core-meetingbot`> Meeting started Fri Mar 11 19:00:17 2022 UTC. The chair is achow101. Information about MeetBot at https://bitcoin.jonasschnelli.ch/ircmeetings. 19:00:17 <core-meetingbot`> Available commands: action commands idea info link nick 19:00:35 <michaelfolkson> hi 19:00:37 <achow101> #bitcoin -core-dev Wallet Meeting: achow101 _aj_ amiti ariard BlueMatt cfields Chris_Stewart_5 darosior digi_james dongcarl elichai2 emilengler fanquake fjahr gleb glozow gmaxwell gwillen hebasto instagibbs jamesob jarolrod jb55 jeremyrubin jl2012 jnewbery jonasschnelli jonatack jtimon kallewoof kanzure kvaciral laanwj larryruane lightlike luke-jr maaku marcofalke meshcollider michagogo moneyball morcos Murch nehan NicolasDorier paveljanik 19:00:37 <achow101> petertodd phantomcircuit promag provoostenator ryanofsky sdaftuar S3RK sipa vasild 19:01:00 <achow101> There are no pre-proposed topics. Anyone have something to discuss? 19:01:25 <michaelfolkson> A couple of mini topics 19:01:27 <sipa> hi 19:02:03 <michaelfolkson> With possible modifications to BIP 371 is this something that we can stew on for a while or does a decision need to be made soon? 19:02:14 <jeremyrubin> yes 19:02:26 <michaelfolkson> I saw rust-bitcoin (?) wanted to merge something/release something? 19:02:33 <achow101> michaelfolkson: I think it is too late to make changes to BIP 371 19:02:46 <sipa> I think so too. 19:03:02 <jeremyrubin> #proposedwalletmeetingtopic what are hww / hwi supposed to do with PSBTs / Signer role functionality 19:03:09 <michaelfolkson> Ok fair enough 19:03:30 <sipa> I suggested the change before knowing it was deployed anywhere. 19:03:37 <michaelfolkson> I'll close my issue then 19:03:55 <michaelfolkson> We can go to Jeremy's topic 19:04:00 <jeremyrubin> have you talked to salvatore sipa? it's ledger that deployed right? 19:04:17 <sipa> he commented on the issue 19:04:27 <achow101> Others may have as well. We don't know. 19:04:30 <michaelfolkson> https://github.com/bitcoin/bitcoin/issues/24492 19:04:47 <sipa> but just the fact that anyone already implemented it, thinking is was complete, makes the bar to change it a lot higher 19:04:53 <sipa> they may not be the only one 19:05:24 <jeremyrubin> michaelfolkson: you should include this in your BIP process tweaks, we should add some kind of 'dontimplementyet' type tag 19:05:48 <sipa> I don't think that helps. This BIP wouldn't have had such a tag. 19:06:04 <sipa> I was just too late with my feedback; so be it. 19:06:11 <achow101> Ideally the "don't implement yet" stage is when it's on the mailng list prior to being PR'd to bips 19:06:37 <achow101> and that people would comment on BIPs when they are proposed to the mailing list before the PR is opened 19:06:48 <jeremyrubin> > ideally 19:08:01 <michaelfolkson> The BIP is still draft. Presumably now it is implemented in the wild that should just move to final 19:08:09 <jeremyrubin> draft is kinda meaningless 19:08:22 <achow101> indeed... 19:08:24 <sipa> I think tis discussion does not belong here 19:08:27 <sipa> *this 19:08:28 <jeremyrubin> sipa: +1 19:08:31 <michaelfolkson> Fair enough 19:08:34 <achow101> #topic what are hww / hwi supposed to do with PSBTs / Signer role functionality (jeremyrubin) 19:08:34 <core-meetingbot`> topic: what are hww / hwi supposed to do with PSBTs / Signer role functionality (jeremyrubin) 19:08:46 <jeremyrubin> so there has been a little discussion in rust-miniscript on this 19:08:58 <jeremyrubin> see https://github.com/rust-bitcoin/rust-miniscript/pull/305 19:09:29 <jeremyrubin> basically, it's not really clear (at least *to me*) what is supposed to happen with the satisfaction of miniscript stuff w.r.t. HWWs 19:09:57 <jeremyrubin> i.e., BIP-174 defines things that a signer must verify (like the parent txns of all outputs being spent AFAIU?) 19:10:15 <jeremyrubin> but it's not really clear to me either if the signer is in HWW how that data is getting shuttled over to the singing 'enclave' 19:11:02 <jeremyrubin> rust-miniscript has this thing called a Satisfier which is an API to "look up" a key out of the PSBT itself, which in theory could be used to "look up" a signature out of HWW (if it sent it all the right information?) 19:11:02 <achow101> jeremyrubin: the psbt is supposed to contain all of the things the hww needs in order to sign 19:11:44 <sipa> this seems more like rust-miniscript API question than a question about wallets (and even less about bitcoin core's wallet) 19:12:20 <jeremyrubin> well in 174 it says "Before signing a non-witness input, the Signer must verify that the TXID of the non-witness UTXO matches the TXID specified in the unsigned transaction." 19:13:11 <sipa> is that not clear? 19:13:13 <jeremyrubin> but it's not really clear to me in the PSBT which data we've defined to allow that verification 19:13:45 <jeremyrubin> how do we verify that? don't we need the entire parent TX to check that Outpoint(Txid(tx), i) == input.outpoint 19:14:00 <achow101> jeremyrubin: that's provided in the psbt 19:14:04 <achow101> as non_witness_utxo 19:14:19 <sipa> the entire parent tx is "the non-witness UTXO", which is a field in the PSBT 19:15:37 <jeremyrubin> ahh ok i see 19:16:47 <achow101> anything else to discuss? 19:17:23 <michaelfolkson> 6 hour turnaround on #24530 from opening to merging? :) 19:17:24 <gribble> https://github.com/bitcoin/bitcoin/issues/24530 | wallet: assert BnBs internally calculated waste is the same as GetSelectionWaste by glozow ÷ Pull Request #24530 ÷ bitcoin/bitcoin ÷ GitHub 19:17:33 <michaelfolkson> Very small change admittedly 19:17:57 <michaelfolkson> But you seem like a quick merger achow101 :) 19:18:28 <achow101> #endmeeting