Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 3275B1BB for ; Sat, 30 Sep 2017 23:23:55 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from zinan.dashjr.org (zinan.dashjr.org [192.3.11.21]) by smtp1.linuxfoundation.org (Postfix) with ESMTP id 206651B4 for ; Sat, 30 Sep 2017 23:23:53 +0000 (UTC) Received: from ishibashi.localnet (unknown [IPv6:2001:470:5:265:a45d:823b:2d27:961c]) (Authenticated sender: luke-jr) by zinan.dashjr.org (Postfix) with ESMTPSA id D233138A0072; Sat, 30 Sep 2017 23:23:33 +0000 (UTC) X-Hashcash: 1:25:170930:bitcoin-dev@lists.linuxfoundation.org::iOfjew/2sJwsUrf4:oi+t X-Hashcash: 1:25:170930:mark@friedenbach.org::aW+QVJk3qBO5aVm9:a+DV9 From: Luke Dashjr To: bitcoin-dev@lists.linuxfoundation.org, Mark Friedenbach Date: Sat, 30 Sep 2017 23:23:32 +0000 User-Agent: KMail/1.13.7 (Linux/4.12.5-gentoo; KDE/4.14.34; x86_64; ; ) References: <5B6756D0-6BEF-4A01-BDB8-52C646916E29@friedenbach.org> In-Reply-To: <5B6756D0-6BEF-4A01-BDB8-52C646916E29@friedenbach.org> X-PGP-Key-Fingerprint: E463 A93F 5F31 17EE DE6C 7316 BD02 9424 21F4 889F X-PGP-Key-ID: BD02942421F4889F X-PGP-Keyserver: hkp://pgp.mit.edu MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201709302323.33004.luke@dashjr.org> X-Spam-Status: No, score=-2.3 required=5.0 tests=RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD autolearn=disabled version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org Subject: Re: [bitcoin-dev] Merkle branch verification & tail-call semantics for generalized MAST X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 30 Sep 2017 23:23:55 -0000 On Thursday 07 September 2017 12:38:55 AM Mark Friedenbach via bitcoin-dev wrote: > Tail-call execution semantics > BIP: https://gist.github.com/maaku/f7b2e710c53f601279549aa74eeb5368 > Code: https://github.com/maaku/bitcoin/tree/tail-call-semantics Just noticed this doesn't count sigops toward the block sigop limit. Is that really safe? How long would it take, to verify a malicious block with only inputs such that there is nearly 4 MB of sigops? (I do already understand the difficulty in supporting the sigop limit.) Luke