Return-Path: Received: from smtp1.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by lists.linuxfoundation.org (Postfix) with ESMTP id 742B3C0032 for ; Sat, 11 Mar 2023 20:53:27 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id 4F470818BE for ; Sat, 11 Mar 2023 20:53:27 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org 4F470818BE Authentication-Results: smtp1.osuosl.org; dkim=pass (1024-bit key) header.d=dashjr.org header.i=@dashjr.org header.a=rsa-sha256 header.s=zinan header.b=M1/Uxz3M X-Virus-Scanned: amavisd-new at osuosl.org X-Spam-Flag: NO X-Spam-Score: -2.101 X-Spam-Level: X-Spam-Status: No, score=-2.101 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 3Lqc2JNP86iC for ; Sat, 11 Mar 2023 20:53:26 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org 459E7818A7 Received: from zinan.dashjr.org (zinan.dashjr.org [192.3.11.21]) by smtp1.osuosl.org (Postfix) with ESMTP id 459E7818A7 for ; Sat, 11 Mar 2023 20:53:26 +0000 (UTC) Received: from [192.168.77.250] (unknown [12.151.133.18]) (Authenticated sender: luke-jr) by zinan.dashjr.org (Postfix) with ESMTPSA id AF99638AF3CF; Sat, 11 Mar 2023 20:53:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=dashjr.org; s=zinan; t=1678568004; bh=0BiUA+4jj63st8770Dx+ubG8stVI+BxWx/wD2OhXBHI=; h=Date:Subject:To:References:From:In-Reply-To; b=M1/Uxz3Mq82bl+BotupZhEHsyhqXviW+ae2VueuSuHesBIPxYXdU1nRmdkE/mYS6h 1POe36jisxQjvwnFr2+Wr8808vWWt41G9XapT7/cPlGM3A1duM8/AlNRcSptC0HlX1 a0d46hNQO1sfuW1k5RDI+ZjZIS2VyoSAoF66Ti+A= Message-ID: <4652dbe8-6647-20f2-358e-be0ef2e52c47@dashjr.org> Date: Sat, 11 Mar 2023 15:53:21 -0500 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.8.0 To: James O'Beirne , Bitcoin Protocol Discussion References: Content-Language: en-US From: Luke Dashjr In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Subject: Re: [bitcoin-dev] BIP for OP_VAULT X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 11 Mar 2023 20:53:27 -0000 I started reviewing the BIP, but stopped part way through, as it seems to have a number of conceptual issues. I left several comments on the PR (https://github.com/bitcoin/bips/pull/1421#pullrequestreview-1335925575), but ultimately I think it isn't simplified enough for day-to-day use, and would harm privacy quite a bit. Instead, I would suggest a new approach where: 1) Joe receives funds with a taproot output like normal. 2) Joe sends funds to Fred, but Fred cannot spend them until N blocks later (covenant-enforced relative locktime). Ideally, this should use/support a taproot keypath spend somehow. It would be nice to blind the particular relative locktime somehow too, but that may be too expensive. 2b) If Joe's funds were stolen, Joe can spend Fred's UTXO within the N block window to a recovery output. Unfortunately, the implementation details for this kind of setup are non-obvious and will likely require yet another address format (or at least recipient-wallet changes), but certainly seems within the scope of possibility. Thoughts? Luke On 2/13/23 16:09, James O'Beirne via bitcoin-dev wrote: > Since the last related correspondence on this list [0], a number of > improvements have been made to the OP_VAULT draft [1]: > > * There is no longer a hard dependence on package relay/ephemeral >   anchors for fee management. When using "authorized recovery," all >   vault-related transactions can be bundled with unrelated inputs and >   outputs, facilitating fee management that is self contained to the >   transaction. Consequently, the contents of this proposal are in theory >   usable today. > > * Specific output locations are no longer hardcoded in any of the >   transaction validation algorithms. This means that the proposal is now >   compatible with future changes like SIGHASH_GROUP, and >   transaction shapes for vault operations are more flexible. > > --- > > I've written a BIP that fully describes the proposal here: > > https://github.com/jamesob/bips/blob/jamesob-23-02-opvault/bip-vaults.mediawiki > > The corresponding PR is here: > > https://github.com/bitcoin/bips/pull/1421 > > My next steps will be to try for a merge to the inquisition repo. > > Thanks to everyone who has participated so far, but especially to AJ and > Greg for all the advice. > > James > > [0]: > https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2023-January/021318.html > [1]: https://github.com/bitcoin/bitcoin/pull/26857 > > _______________________________________________ > bitcoin-dev mailing list > bitcoin-dev@lists.linuxfoundation.org > https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev