Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id AF45D308 for ; Sun, 30 Aug 2015 18:56:35 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.7.6 Received: from mail-io0-f174.google.com (mail-io0-f174.google.com [209.85.223.174]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id A62E0191 for ; Sun, 30 Aug 2015 18:56:34 +0000 (UTC) Received: by iog7 with SMTP id 7so14750569iog.2 for ; Sun, 30 Aug 2015 11:56:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:date:message-id:subject:from:to:content-type; bh=F+zzYW7AfQf8wDpVZ0Y4ka5mO3KywIJkcsffFxmaCLY=; b=Va7sZVprTGzzNYSUFrrIt7By6nY13aCH7AUXktyCTjO7Xebyx3ITCIsaElnwzJHys/ qdgqVgQ5eUg+3TWZNTqMLjsNSLjVIIzyN6DAEEBpX4aMn29uhokz/xuFDPspAXcPTRPW eatGnW+SStNqxARoU619u0B7boGx/wnPBe+/524qDYLSVaN5c3oFd5pnoWIJ+3yMj6fp xiLpHoV67juppxAtHnmZ8nbxmNnOdkPuBjnFRJH2i1uxXqdHSvTVHF9xgJP1zrjp5ODu +LgkdUXzfS6yKGI8ed924quKXX0rv79kM4gOX45P7Sa4YnQTnsucY17MzAFMbQpHz0YL ZG5A== MIME-Version: 1.0 X-Received: by 10.107.7.168 with SMTP id g40mr24445299ioi.28.1440960994144; Sun, 30 Aug 2015 11:56:34 -0700 (PDT) Received: by 10.36.19.141 with HTTP; Sun, 30 Aug 2015 11:56:34 -0700 (PDT) Date: Sun, 30 Aug 2015 13:56:34 -0500 Message-ID: From: Bryan Bishop To: Bitcoin Dev , Bryan Bishop Content-Type: text/plain; charset=UTF-8 X-Spam-Status: No, score=-2.7 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, 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: [bitcoin-dev] Short review of previously-proposed exotic SIGHASH types X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Development Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 30 Aug 2015 18:56:35 -0000 Here is a short review of previously-proposed and exotic SIGHASH types. SIGHASH_MULTIPLE SIGHASH_LIST: https://bitcointalk.org/index.php?topic=252960.0 https://bitcointalk.org/index.php?topic=212555.0 SIGHASH_MULTIPLE SIGHASH_WITHINPUTVALUE: https://bitcointalk.org/index.php?topic=191003.0 SIGHASH_WITHINPUTVALUE: http://lists.linuxfoundation.org/pipermail/bitcoin-dev/2015-January/007185.html SIGHASH_NOINPUT: https://github.com/Roasbeef/bitcoin/commit/4b3c3f1baf7985208ceb6887261ee150ab6e3328 https://github.com/Roasbeef/btcd/commit/67830e506fa135d5239177340918cea39909e6a4 http://lightning.network/lightning-network-paper.pdf SIGHASH_NORMALIZED SIGHASH_NOINPUT: http://diyhpl.us/wiki/transcripts/sf-bitcoin-meetup/2015-02-23-scaling-bitcoin-to-billions-of-transactions-per-day/ SIGHASH_WITHOUT_PREV_SCRIPTPUBKEY SIGHASH_WITHOUT_PREV_VALUE SIGHASH_WITHOUT_INPUT_TXID SIGHASH_WITHOUT_INPUT_INDEX SIGHASH_WITHOUT_INPUT_SEQUENCE SIGHASH_WITHOUT_OUTPUT_SCRIPTPUBKEY SIGHASH_WITHOUT_OUTPUT_VALUE SIGHASH_WITHOUT_INPUTS SIGHASH_WITHOUT_OUTPUTS SIGHASH_WITHOUT_INPUT_SELF SIGHASH_WITHOUT_OUTPUT_SELF SIGHASH_WITHOUT_TX_VERSION SIGHASH_WITHOUT_TX_LOCKTIME SIGHASH_SIGN_STACK_ELEMENT: https://github.com/scmorse/bitcoin-misc/blob/master/sighash_proposal.md Similarly, petertodd has asked for a SIGHASH_DONT_SIGN_TXID before to make OP_CODESEPARATOR more useful. SIGHASH_DANGEROUSLYPROMISCUOUS: http://gnusha.org/bitcoin-wizards/2015-04-17.log SIGHASH_DOUBLE: 06:41 < lorenzoasr> maybe a SIGHASH_DOUBLE that signs INPUT[i] and OUTPUT[i] and OUTPUT[i+1] could be very helpful Some sighash types briefly proposed by petertodd in #bitcoin-dev: SIGHASH_NLOCKTIMEVERIFY SIGHASH_SUM (for merging multiple payments) And finally one from wumpus (#bitcoin-dev): SIGHASH_UNICORN - Bryan http://heybryan.org/ 1 512 203 0507