Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 928DEF3F for ; Thu, 21 Apr 2016 17:29:38 +0000 (UTC) X-Greylist: delayed 00:05:45 by SQLgrey-1.7.6 Received: from mail.sldev.cz (mail.sldev.cz [51.254.7.247]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 0D77819E for ; Thu, 21 Apr 2016 17:29:38 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by mail.sldev.cz (Postfix) with ESMTP id 7AEF4E6D4; Thu, 21 Apr 2016 17:23:57 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at mail.sldev.cz Received: from mail.sldev.cz ([127.0.0.1]) by localhost (mail.sl [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id EWTb0w_5yqj8; Thu, 21 Apr 2016 17:23:57 +0000 (UTC) Received: from tetra.site (unknown [10.8.8.107]) by mail.sldev.cz (Postfix) with ESMTPSA id DA4B0E66E; Thu, 21 Apr 2016 17:23:56 +0000 (UTC) To: Eric Lombrozo , bitcoin-dev@lists.linuxfoundation.org References: <5717AF19.1030102@gmail.com> From: Pavol Rusnak Message-ID: <57190CA4.8020809@satoshilabs.com> Date: Thu, 21 Apr 2016 19:23:48 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org X-Mailman-Approved-At: Thu, 21 Apr 2016 18:42:44 +0000 Subject: Re: [bitcoin-dev] Proposal to update BIP-32 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: Thu, 21 Apr 2016 17:29:38 -0000 On 21/04/16 17:28, Eric Lombrozo via bitcoin-dev wrote: > I don't think we've ever had to handle this case. This is the main problem: we are not sure, because not a lot of software does this checks. Also even if you do check, it's hard to handle an exception (you can't always skip - what if the problematic node is m/44'?). One of the motivations is to fix BIP-32 so it can be used for non-secp256k1 curves as well. For NIST P-256 curve this chance is 2^-32. Jochen even managed to find an example[1]: m/28578'/33941 where m is derived from "000102030405060708090a0b0c0d0e0f" seed. [1] https://github.com/trezor/trezor-crypto/commit/16ff4387ae79429e629a5454708abf7385b3a9a3 -- Best Regards / S pozdravom, Pavol "stick" Rusnak SatoshiLabs.com