From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id CFEC798F for ; Wed, 20 Jul 2016 05:46:59 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from outmail148102.authsmtp.net (outmail148102.authsmtp.net [62.13.148.102]) by smtp1.linuxfoundation.org (Postfix) with ESMTP id 0EA2EA5 for ; Wed, 20 Jul 2016 05:46:58 +0000 (UTC) Received: from mail-c247.authsmtp.com (mail-c247.authsmtp.com [62.13.128.247]) by punt20.authsmtp.com (8.14.2/8.14.2/) with ESMTP id u6K5kvbo085476; Wed, 20 Jul 2016 06:46:57 +0100 (BST) Received: from petertodd.org (ec2-52-5-185-120.compute-1.amazonaws.com [52.5.185.120]) (authenticated bits=0) by mail.authsmtp.com (8.14.2/8.14.2/) with ESMTP id u6K5ktsg051023 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 20 Jul 2016 06:46:56 +0100 (BST) Received: from [127.0.0.1] (localhost [127.0.0.1]) by petertodd.org (Postfix) with ESMTPSA id A572840104; Wed, 20 Jul 2016 05:44:21 +0000 (UTC) Received: by localhost (Postfix, from userid 1000) id 1037F20576; Wed, 20 Jul 2016 01:46:54 -0400 (EDT) Date: Wed, 20 Jul 2016 01:46:54 -0400 From: Peter Todd To: Sean Bowe , Bitcoin Protocol Discussion Message-ID: <20160720054654.GA1420@fedora-21-dvm> References: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="CE+1k2dSO48ffgeK" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) X-Server-Quench: 5e554775-4e3d-11e6-bcde-0015176ca198 X-AuthReport-Spam: If SPAM / abuse - report it at: http://www.authsmtp.com/abuse X-AuthRoute: OCd2Yg0TA1ZNQRgX IjsJECJaVQIpKltL GxAVKBZePFsRUQkR aAdMdAIUEkAYAgsB AmAbW1JeVFt7XGU7 bghPaBtcak9QXgdq T0pMXVMcUQMTBEdF RUkeVxhydQYIfHdx ZwhnC3VeWEN9cFt5 F00ACGwHMGF9OjNL BV1YdwJRcQRMLU5E Y1gxNiYHcQ5VPz4z GA41ejw8IwAXAgVt Cg0XJFwOEw4rIhoX DwwYFDM0FEYZRiI1 NHQA X-Authentic-SMTP: 61633532353630.1038:706 X-AuthFastPath: 0 (Was 255) X-AuthSMTP-Origin: 52.5.185.120/25 X-AuthVirus-Status: No virus detected - but ensure you scan with your own anti-virus system. X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_LOW autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org Subject: Re: [bitcoin-dev] BIP draft: HTLC transactions 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: Wed, 20 Jul 2016 05:47:00 -0000 --CE+1k2dSO48ffgeK Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Jul 19, 2016 at 10:35:39PM -0600, Sean Bowe via bitcoin-dev wrote: > I'm requesting feedback for Hash Time-Locked Contract (HTLC) transactions > in Bitcoin. >=20 > HTLC transactions allow you to pay for the preimage of a hash. CSV/CLTV c= an > be used to recover your funds if the other party is not cooperative. These > scripts take the following general form: >=20 > [HASHOP] OP_EQUAL > OP_IF > > OP_ELSE > [TIMEOUTOP] OP_DROP > OP_ENDIF > OP_CHECKSIG Note that because you're hashing the top item on the stack regardless scriptSig's that satisfy HTLC's are malleable: that top stack item can be changed anything in the digest-not-provided case and the script still passe= s. --=20 https://petertodd.org 'peter'[:-1]@petertodd.org --CE+1k2dSO48ffgeK Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- iQEcBAEBCAAGBQJXjxBKAAoJEGOZARBE6K+y0zoH/32Xxikl8kJIDLmpsrTsqDDM HkO3CvhkSwSp/VghY/Y8slJfybXTmBm68lgKuGJENqpvY/MuYf2xZdsHGpRQqkCD mjtdsOUK00qkM8/izhFdM5Wp8JVkC7+TeZ0yZ3kC5jckx0SF5GRgoLIE41Hyq3/B kafFjXJ/0a7oA0yV+3M0AtJ77MuXwMoQPkEZ3vIdo9V6o0YVrq7kV6fVN7H4BnW3 XwCtqCArWH3YzR+soK37zclA+eILMJtxetiaDktP10ZiqOnVR/OU/1hXh8i4y4CQ uYUN3inXPNn+GDGL/ywyETp88uxaOOMxq+di3ofNfw3fPaRCh7Td8uP45vJlJJo= =bIEY -----END PGP SIGNATURE----- --CE+1k2dSO48ffgeK--