openoms

Running Bitcoin Core.

@notgrubles @RCasatta @blinkbtc @blinkbtcdev @Breez_Tech @spark This is the statechain trust model: Theft needs all n operators colluding. One honest operator that deleted its key share blocks this.

If the backend is the prior owner, and in statechains the server can theoretically collude with the prior owner to rugpull, wouldn't consolidating risk your money? So if you go to attempt to make your exit economical, you are simultaneously risking full blown rugpulling before you can exit?

I force-exited a non-custodial Blink wallet (using Spark) on Bitcoin mainnet. Seed only, no operators. 100,000 sats in → 89,668 reach the destination. 18 of 22 leaves were dust costing more to exit than they hold. The exit works, but it's a fire escape, not a door.

@notgrubles @RCasatta @blinkbtc @blinkbtcdev @Breez_Tech @spark In the swaps the new leaves come from the SSP inventory. At the same time the swapped in leaves become part of the inventory.

@openoms @RCasatta @blinkbtc @blinkbtcdev @Breez_Tech @spark Where do the new leaves come from? A pool the SSP maintains? Other users?

@the_ecash The exit cost goes up 10x. Can run the numbers with the repo.

@openoms What would have happened at a 10sat/b fee rate?

Correction: "seed only, no operators" compressed two steps. The leaf data (recovery bundle) must be fetched while operators are online. The exit itself then needs nothing from them: seed + saved bundle is the accurate claim. Full mechanics and costs: github.com/blinkbitcoin/s…

@callebtc @blinkbtc @blinkbtcdev @Breez_Tech @spark All three are in the statechain trust model: 1: True until you save the bundle. After that, exposure is only what changed since last sync and withholding is detectable. 2+3: theft needs all n operators colluding. One honest operator that deleted its key share blocks both.

@openoms @blinkbtc @blinkbtcdev @Breez_Tech @spark hmmmmm. - if they don’t give your leaf data, you can’t withdraw your coins - if they collude with the previous owner they can steal those leaves - if they were the original minter of all leaves they can steal all that money on the statechain

@januszg_ @blinkbtc @blinkbtcdev @Breez_Tech @spark Blink does use the Breez SDK for the non-custodial accounts: x.com/Breez_Tech/sta…

@openoms @blinkbtc @blinkbtcdev @Breez_Tech @spark assuming blink not use breez sdk?

@RCasatta @blinkbtc @blinkbtcdev @Breez_Tech @spark Yes, the wallets need to implement this. The consolidation comes with a tradeoff between efficient unilateral exit and fast transactions (lacking denominations will need more swaps with SSPs at payment time). Adding this to the tool:

@openoms @blinkbtc @blinkbtcdev @Breez_Tech @spark Is it a spark protocol issue or wallet implementation issue? Should in theory be possible to store the data after every transaction and cooperative consolidate from time to time to be ready for a fee-efficient unilateral exit, right?

🚀 LFG 🚀 @andrew_s_toth’s parallel input prevout fetcher was just merged into Bitcoin Core for the upcoming v32 - after 2+ years and 1000+ review comments. IBD is getting *even* faster \:D/ Thank you for the persistence, Andrew: this is what open-source collaboration should look like! github.com/bitcoin/bitcoi…

@brian_trollz @blinkbtc @blinkbtcdev @Breez_Tech @spark The screenshot shows the first economical leaf to exit took 7 transactions. It was the same for all four and the number was the same for the non-economical ones. Then there is the sweep on top after the timeouts are reached.

@openoms @blinkbtc @blinkbtcdev @Breez_Tech @spark How deep was the TX tree for each leaf?

@BitcoinScoresby @blinkbtc @blinkbtcdev @Breez_Tech @spark Please check again.

@openoms @blinkbtc @blinkbtcdev @Breez_Tech @spark The links were 404 for me, is there another place I can find them?

Bitcoin Core v31.1 was released! It is available from: bitcoincore.org/en/download/ Release notes: bitcoincore.org/en/releases/31…

Correction: "seed only, no operators" compressed two steps. The leaf data (recovery bundle) must be fetched while operators are online. The exit itself then needs nothing from them: seed + saved bundle is the accurate claim. Full mechanics and costs: github.com/blinkbitcoin/s…

@notgrubles @PeteClubSeven @blinkbtc @blinkbtcdev @Breez_Tech @spark No. The seed alone is not enough: the exit needs the leaf data, fetched while operators are online. I saved that bundle first, the exit itself then ran without them. "Seed only" overclaimed, fair hit. Accurate claim: seed + saved recovery bundle, then no operators needed.

@openoms @PeteClubSeven @blinkbtc @blinkbtcdev @Breez_Tech @spark Can you input a published Blink wallet app seed into a Spark recovery tool and do a unilateral exit without the Spark backend being online? Yes or no.

@PeteClubSeven @notgrubles @blinkbtc @blinkbtcdev @Breez_Tech @spark Both are true. Operators were also needed to get funds to Spark in the first place.

@openoms @notgrubles @blinkbtc @blinkbtcdev @Breez_Tech @spark This is the exactly same response Roy gives about the Breez SDK. Do you stand by the line in your OP that the exit was "seed only, no operators" even though you clearly had to download your recovery bundle from an operator?

@francispouliot_ @blinkbtc @blinkbtcdev @Breez_Tech @spark Was changed recently, please check again.

@openoms @blinkbtc @blinkbtcdev @Breez_Tech @spark 404 on the repository, its probably private?

@PeteClubSeven @notgrubles @blinkbtc @blinkbtcdev @Breez_Tech @spark Working on exactly this to be implemented in Blink and available for others: github.com/blinkbitcoin/s… and yes the offchain data needs to be get from the operators while they are online. Then you can keep it and use it even after they went offline.

> There were no operators needed for the exit demonstrated Where did the recovery bundle come from? Where can users get their recovery bundle? What service can they use to keep their recovery bundle up to date? You know all of these questions are incredibly important but you're acting like somehow the process of users starting a unilateral exit doesn't involve this immensely important data. If I download Wallet of Satoshi, or Cake, or Blitz, or any of the rest. How can I start a unilateral exit without reaching out to a spark operator? It's impossible, none of the wallets keep the data local. I have to request a recovery bundle from the operator before I can dream of performing a unilateral exit. This is intellectually dishonest.

@PeteClubSeven @notgrubles @blinkbtc @blinkbtcdev @Breez_Tech @spark There were no operators needed for the exit demonstrated, but they are needed to transact and to refresh the recovery bundle: x.com/openoms/status…

This whole thread feels like something is off. You claimed no operators were required, then you backtracked and said it requires no more permission than transacting but the whole point why unilateral exits matter to users is that they have an option to retrieve their funds if they get banned from a service or if the service fails. It's not about whether they have enough permission to do so.

@notgrubles Read the nuanced take: njump.me/nevent1qqstvsu…

For people reading this, "no operators" is false. You have to continually poll the Spark backend for the leaf data. No Breez SDK wallet (including Blink) does this, so if Spark goes offline then you are left high and dry without any leaf data to broadcast onchain.

@notgrubles @blinkbtc @blinkbtcdev @Breez_Tech @spark I can't tell what others do, but I have started to work on this a while ago before the X threads started and Bark had an alternative.

@openoms @blinkbtc @blinkbtcdev @Breez_Tech @spark Can you explain how all of these Breez SDK wallets like Cake etc. have deployed Spark support but never notified their users about this unimplemented trustless exit? Why am I having to push the entire Spark wallet ecosystem to implement this?

@notgrubles @blinkbtc @blinkbtcdev @Breez_Tech @spark Again, everything covered by the last successful refresh stays unilaterally exitable even if Spark goes offline. Wallets need to implement the bundle refresh, we are working on it. Thanks for pushing us.

@openoms @blinkbtc @blinkbtcdev @Breez_Tech @spark Yes it's nice to talk about this stuff, but the reality is users of Blink and every other Breez SDK Spark wallet are basically screwed if the Spark backend goes offline again. I don't know how this was allowed to happen.