From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id 2B4A2C000D; Thu, 7 Oct 2021 04:52:12 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id 0B73B4095A; Thu, 7 Oct 2021 04:52:12 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org X-Spam-Flag: NO X-Spam-Score: 0.297 X-Spam-Level: X-Spam-Status: No, score=0.297 tagged_above=-999 required=5 tests=[BAYES_40=-0.001, 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_H2=-0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no Authentication-Results: smtp4.osuosl.org (amavisd-new); dkim=pass (1024-bit key) header.d=protonmail.com Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id JzJS_prmHyK9; Thu, 7 Oct 2021 04:52:11 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 Received: from mail-4324.protonmail.ch (mail-4324.protonmail.ch [185.70.43.24]) by smtp4.osuosl.org (Postfix) with ESMTPS id 473EF40957; Thu, 7 Oct 2021 04:52:11 +0000 (UTC) Date: Thu, 07 Oct 2021 04:52:01 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=protonmail.com; s=protonmail; t=1633582328; bh=bHIXovPLY/1Q/zQ+SiAWUtPgwP36R5gioU7FPeSceV4=; h=Date:To:From:Cc:Reply-To:Subject:In-Reply-To:References:From; b=aDA3vPiAGw3eUoJC0AbCyWqC2XiHpLJVcegA3hsjpC6+MGU5ibZ5ckN7ljc+L7Ct9 0Ij/Mr1AXo8Oi2B50JMvWLzAxAIxnpqURD18O+++gPzlOFKPElxOsql8VZ5ZNjxRMu dZUToyMJy6AcAEcYSoyn22+mFW3mZT7YFYTiBKfY= To: Erik Aronesty From: ZmnSCPxj Reply-To: ZmnSCPxj Message-ID: In-Reply-To: References: <20210808215101.wuaidu5ww63ajx6h@ganymede> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Cc: Bitcoin Protocol Discussion , lightning-dev Subject: Re: [bitcoin-dev] [Lightning-dev] Removing the Dust Limit 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: Thu, 07 Oct 2021 04:52:12 -0000 Good morning e, > mostly thinking out loud > > suppose there is a "lightweight" node: > > 1. ignores utxo's below the dust limit > 2. doesn't validate dust tx > 3. still validates POW, other tx, etc. > > these nodes could possibly get forked - accepting a series of valid, > mined blocks where there is an invalid but ignored dust tx, however > this attack seems every bit as expensive as a 51% attack How would such a node treat a transaction that spends multiple dust UTXOs a= nd creates a single non-dust UTXO out of them (after fees)? Is it valid (to such a node) or not? I presume from #1 it never stores dust UTXOs, so the node cannot know if th= e UTXO being spent by such a tx is spending dust, or trying to spend an alr= eady-spent TXO, or even inventing a TXO out of `/dev/random`. Regards, ZmnSCPxj