From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.osuosl.org (smtp1.osuosl.org [IPv6:2605:bc80:3010::138]) by lists.linuxfoundation.org (Postfix) with ESMTP id 07347C0037 for ; Tue, 30 Jan 2024 05:17:17 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id D603383123 for ; Tue, 30 Jan 2024 05:17:16 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org D603383123 Authentication-Results: smtp1.osuosl.org; dkim=pass (2048-bit key) header.d=protonmail.com header.i=@protonmail.com header.a=rsa-sha256 header.s=protonmail3 header.b=dKuhDyIF X-Virus-Scanned: amavisd-new at osuosl.org X-Spam-Flag: NO X-Spam-Score: 0.901 X-Spam-Level: X-Spam-Status: No, score=0.901 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, FREEMAIL_FROM=0.001, FROM_LOCAL_NOVOWEL=0.5, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001, TO_EQ_FM_DIRECT_MX=2.5] autolearn=no 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 AGk_zfStfF49 for ; Tue, 30 Jan 2024 05:17:15 +0000 (UTC) X-Greylist: delayed 581 seconds by postgrey-1.37 at util1.osuosl.org; Tue, 30 Jan 2024 05:17:15 UTC DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org 8E97583022 Received: from mail-4318.protonmail.ch (mail-4318.protonmail.ch [185.70.43.18]) by smtp1.osuosl.org (Postfix) with ESMTPS id 8E97583022 for ; Tue, 30 Jan 2024 05:17:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=protonmail.com; s=protonmail3; t=1706591833; x=1706851033; bh=jEuAEsBM6uZ8NaY1RMAA3ctzjz97IyBUMhmoaj2ivAo=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: Feedback-ID:From:To:Cc:Date:Subject:Reply-To:Feedback-ID: Message-ID:BIMI-Selector; b=dKuhDyIFYT37YKdKCi1vDQkxqJ3MAeqG5HZQqpwL/LR9KMJs35xn/TWwKEx6iQS8D pbitabMdYmKwwWTinw0EgWMtxci+a4Al2t02Pl0rpO0m2wWGO4dQFy+lazAUkq2JTT 0N3UDPR8/ao5AFOwBTxYeXV3CIR+MZjhYbL7JhSxHf7xkgaLUunpxXWzss6BNu0v94 LYywnctWuSZYWx2cU7inXDOfiQ9mGacvU4DKKWhLf1gObcviWoAs/8DTnrOs98Co6F igPGaJo0dpHVG3BqXNVaTTwsCNYGHqRcBIhn13CW1FnFZmdqR0Ns2B/nP7eWD+2bek FsgVVuDfC5fsQ== Date: Tue, 30 Jan 2024 05:17:04 +0000 To: ZmnSCPxj From: ZmnSCPxj Message-ID: In-Reply-To: References: <4619vs2aZBsW1lr3ihqjM6TdRgx8CuA_wRwXetu7jZZcL8r3oWUy7xOPkT-qJ0xxT79_Ss6it2chOWAAWPJuU8YSCzjaNOd6JvnMvWTBc-c=@protonmail.com> <9tVZA3A4x-GZB5wQ1kMUoyyYXqvGS4MP4iDrLx1FCFHly-MU--II8evpgdcf2Xb9JZWDsY0kEB8r9dClzPrOk_V8EiWtHms8fvlunZQNGrA=@protonmail.com> Feedback-ID: 2872618:user:proton MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Cc: bitcoin-dev@lists.linuxfoundation.org, Lightning Dev Subject: Re: [bitcoin-dev] [Lightning-dev] CheckTemplateVerify Does Not Scale Due to UTXO's Required For Fee Payment 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: Tue, 30 Jan 2024 05:17:17 -0000 > I should note that under Decker-Russell-Osuntokun the expectation is that= both counterparties hold the same offchain transactions (hence why it is s= ometimes called "LN-symmetry"). > However, there are two ways to get around this: >=20 > 1. Split the fee between them in some "fair" way. > Definition of "fair" wen? > 2. Create an artificial asymmetry: flip a bit of `nSequence` for the upda= te+state txes of one counterparty, and have each side provide signatures fo= r the tx held by its counterparty (as in Poon-Dryja). > This lets you force that the party that holds a particular update+state t= x is the one that pays fees. No, wait, #2 does not actually work as stated. Decker-Russell-Osuntokun uses `SIGHASH_NOINPUT` meaning the `nSequence` is = not committed in the signature and can be malleated. Further, in order for update transactions to be able to replace one another= , the amount output of the update transaction needs to be the same value as= the input of the update transaction --- meaning cannot deduct the fee from= the channel, at least for the update tx. This forces the update transaction to be paid for by bringing in an externa= l UTXO owned by whoever constructed the update transaction (=3D=3D whoever = started the closing). Regards, ZmnSCPxj