From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp2.osuosl.org (smtp2.osuosl.org [IPv6:2605:bc80:3010::133]) by lists.linuxfoundation.org (Postfix) with ESMTP id 3D840C002B for ; Wed, 22 Feb 2023 16:39:13 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id 0CDB6416ED for ; Wed, 22 Feb 2023 16:39:13 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp2.osuosl.org 0CDB6416ED Authentication-Results: smtp2.osuosl.org; dkim=pass (2048-bit key, unprotected) header.d=messagingengine.com header.i=@messagingengine.com header.a=rsa-sha256 header.s=fm1 header.b=hFNoHTMU X-Virus-Scanned: amavisd-new at osuosl.org X-Spam-Flag: NO X-Spam-Score: -2.603 X-Spam-Level: X-Spam-Status: No, score=-2.603 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id zJswPtMFFuaS for ; Wed, 22 Feb 2023 16:39:12 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp2.osuosl.org 100C7416CB Received: from wout1-smtp.messagingengine.com (wout1-smtp.messagingengine.com [64.147.123.24]) by smtp2.osuosl.org (Postfix) with ESMTPS id 100C7416CB for ; Wed, 22 Feb 2023 16:39:11 +0000 (UTC) Received: from compute5.internal (compute5.nyi.internal [10.202.2.45]) by mailout.west.internal (Postfix) with ESMTP id E24173200708; Wed, 22 Feb 2023 11:39:10 -0500 (EST) Received: from mailfrontend1 ([10.202.2.162]) by compute5.internal (MEProxy); Wed, 22 Feb 2023 11:39:11 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:date:date:feedback-id :feedback-id:from:from:in-reply-to:in-reply-to:message-id :mime-version:references:reply-to:sender:subject:subject:to:to :x-me-proxy:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s= fm1; t=1677083950; x=1677170350; bh=+pGk+7NSjRm/QTjrrme6YlTXFvQz NArE4UR0QdpBkB8=; b=hFNoHTMUKVbDeUrubTB5vOAZq/4k9dZatqE8puuGHvwA 0IRy27YOYjr3liJnOruVvm0E3JRMIB3SnPt0XvDXLGtoSKC7N1U244M0XSJQz4/N LanpI0bOsJDQkySpkHUvQZRIzusxN3N/b6PXRzeR+afg9tMQ5gBKgqnzRbzkp/1I 6j/Bkveu9eWrH9G+6svSWFXau29jFhywoAn22+GKEw9rt03sjSvBbdcL3uSdm7np gNtE7gXRgcdB6xlYKVD+9LYUVF6wR15lcapeglUwnpBm1OvA5xUEW0bB4qmGKnB0 V+wQFxVfsCw/NG9At4d9RDwp1wTfZxzoeoCikYv6aA== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvhedrudejledgkeelucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhepfffhvfevuffkfhggtggujgesghdtreertddtvdenucfhrhhomheprfgvthgv rhcuvfhougguuceophgvthgvsehpvghtvghrthhouggurdhorhhgqeenucggtffrrghtth gvrhhnpeelvdellefftddukeduffejgfefjeeuheeileeftdfgteduteeggeevueethfej tdenucffohhmrghinhepphgvthgvrhhtohguugdrohhrghenucevlhhushhtvghrufhiii gvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpehpvghtvgesphgvthgvrhhtohguugdr ohhrgh X-ME-Proxy: Feedback-ID: i525146e8:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Wed, 22 Feb 2023 11:39:09 -0500 (EST) Received: by localhost (Postfix, from userid 1000) id AFB865F92A; Wed, 22 Feb 2023 11:39:04 -0500 (EST) Date: Wed, 22 Feb 2023 11:39:04 -0500 From: Peter Todd To: Andrew Poelstra Message-ID: References: <177016307-23dca06637e70217317077657442d0d8@pmq7v.m5r2.onet> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="eA6+M1CF4SFN2plB" Content-Disposition: inline In-Reply-To: Cc: Bitcoin Protocol Discussion Subject: Re: [bitcoin-dev] Testing censorship resistance of bitcoin p2p network 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: Wed, 22 Feb 2023 16:39:13 -0000 --eA6+M1CF4SFN2plB Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sat, Feb 18, 2023 at 01:28:38AM +0000, Andrew Poelstra wrote: > On Sat, Feb 18, 2023 at 02:03:15AM +0200, Peter Todd wrote: > > On February 18, 2023 1:35:34 AM GMT+02:00, Andrew Poelstra via bitcoin-= dev=20 > > >You could try statically analyze `` to determine whether the > > >IF branch could ever be taken. For example there is no path through > > >the "inscription script" that would result in all the crap being dropp= ed > > >by the end of the script, violating the CLEANSTACK rule. > > > > > >This sort of filtering, assuming it could be reliably and efficiently > > >done, would at least force inscription scripts to be "plausible", and > > >would greatly increase their space cost by e.g. requiring OP_DROP to be > > >added somewhere hundreds of times. > >=20 > > "greatly increase their space cost"? > >=20 > > Tell me, what is the actual % increase to adding OP_DROPs like you prop= ose? > > >=20 > By standardness rules (where you can have up to 80-byte pushes), a > little over 1%. By consensus (520-byte pushes) less than 0.2%. >=20 > Perhaps "greatly increase" is a stretch :) but if the fee market is > functioning and we're talking about large amounts of data, it's not > trivial either. I would definitely call ~1% trivial. Fees vary more by that on an hour to h= our basis. Anyway, it goes to show that protocols relying on data embedded in Bitcoin transactions would do well to have flexible encoding rules, eg by consideri= ng all PUSHDATA's with certain characteristics to be data, so that encoders ca= n be adapted on the fly if there are any censorship issues. It's also useful if = the rules allow data to be encoded in UTXO outputs, so that censorship of witne= ss data always risks people switching to filling up the UTXO set. A kind of Mutually Assured Destruction threat in a way. FWIW, OpenTimestamps was deliberately designed to have this property. So do= n't mess with it. :D --=20 https://petertodd.org 'peter'[:-1]@petertodd.org --eA6+M1CF4SFN2plB Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCgAdFiEE0RcYcKRzsEwFZ3N5Lly11TVRLzcFAmP2RSYACgkQLly11TVR Lzc5dw//VDyg9Dy7IzuB80yv9LXSoHR5Zv5sTlCYuUMUdhoanoYflKdMIiF8peGu cJ7C7Xwx8+QIkNTUP+mgvlcTEETbZiC7F+k1n6eTavrYGpBMotVlkQHann+NxOU0 RPC2s17mc91Wo12tpbrp+vur4lQ3apnylDxeIeo0xkbsMzsX5XXGh0BPoD8aPT4y jHo4TCBBIpXBOPI86VcbZKCgNrB2pZHRra3RHVjKFT9tyLM58A2qrtybMS2CzAj0 SmJAIzP1V1lmJSc6N/zlNuGwM6rBvG7o9UGZRENPq21Y0mPZ5YwlyerVnoE3AX21 Pwg7vMLOAd90VPmf/WjmGZx9x5050/AP3VmWTYsLnJDlmg/pPYtBF+SQ/EqJTsve lfKSz23S5BFZnrG/6Vn5Vl7HKUfxuNT8/4tQbvZWlzWdX4o80zS3evrJ0Veb8Tv8 g4cPLUA5GGpwu5cm04LCDGyKMy5upX6rK9PiL3dRkuf3BZKfEpe9elLJxX5G2tSb j3KvQFYOLRF0ycv4ecEdhMh6neKhCY4WqcuQGWcFGYg/yySrqA7UtXQfRjuEv8mJ iGHGUNRO4Kz27Om7xDCy4gbi/Y3jBrK6twHcXK7Xid1EWIKFCkh6RWS8DBIi0iqD K61Th/A6qn5r2DbOpeph/n91XZqv4u37KXHtgNt7o18Ue1GtfEk= =Su2o -----END PGP SIGNATURE----- --eA6+M1CF4SFN2plB--