Received: from sog-mx-2.v43.ch3.sourceforge.com ([172.29.43.192] helo=mx.sourceforge.net) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1Vthe4-0007at-D3 for bitcoin-development@lists.sourceforge.net; Thu, 19 Dec 2013 17:44:24 +0000 Received-SPF: pass (sog-mx-2.v43.ch3.sourceforge.com: domain of petertodd.org designates 62.13.148.100 as permitted sender) client-ip=62.13.148.100; envelope-from=pete@petertodd.org; helo=outmail148100.authsmtp.co.uk; Received: from outmail148100.authsmtp.co.uk ([62.13.148.100]) by sog-mx-2.v43.ch3.sourceforge.com with esmtp (Exim 4.76) id 1Vthe2-0003g8-EM for bitcoin-development@lists.sourceforge.net; Thu, 19 Dec 2013 17:44:24 +0000 Received: from mail-c235.authsmtp.com (mail-c235.authsmtp.com [62.13.128.235]) by punt15.authsmtp.com (8.14.2/8.14.2/) with ESMTP id rBJHiCTl045198; Thu, 19 Dec 2013 17:44:12 GMT Received: from petertodd.org (petertodd.org [174.129.28.249]) (authenticated bits=128) by mail.authsmtp.com (8.14.2/8.14.2/) with ESMTP id rBJHi6Fo074940 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Thu, 19 Dec 2013 17:44:09 GMT Date: Thu, 19 Dec 2013 12:44:06 -0500 From: Peter Todd To: Amir Taaki , unsystem@lists.dyne.org, bitcoin-development@lists.sourceforge.net, w@grabhive.com Message-ID: <20131219174406.GA12740@petertodd.org> References: <20131219131706.GA21179@savin> <538d3c4677a4332ae8341e37d1a77d5e.squirrel@fruiteater.riseup.net> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="wRRV7LY7NUeQGEoC" Content-Disposition: inline In-Reply-To: <538d3c4677a4332ae8341e37d1a77d5e.squirrel@fruiteater.riseup.net> User-Agent: Mutt/1.5.21 (2010-09-15) X-Server-Quench: 2a5e0d9e-68d5-11e3-b802-002590a15da7 X-AuthReport-Spam: If SPAM / abuse - report it at: http://www.authsmtp.com/abuse X-AuthRoute: OCd2Yg0TA1ZNQRgX IjsJECJaVQIpKltL GxAVKBZePFsRUQkR bgdMdwsUHFAXAgsB AmUbWlNeVFl7WWo7 ag1VcwRfa1RMVxto VEFWR1pVCwQmQ257 fkcYJEZycAFPfH4+ Z0NgXXUVXhV/IEYp SxtJE2VSYHphaTUc TRJQdwFJcANIexZF O1F6ACIKLwdSbGoU FhUwADk1OThDYA5Y WR1FFUgbSloKFTMn L9Ho X-Authentic-SMTP: 61633532353630.1023:706 X-AuthFastPath: 0 (Was 255) X-AuthSMTP-Origin: 174.129.28.249/587 X-AuthVirus-Status: No virus detected - but ensure you scan with your own anti-virus system. X-Spam-Score: -0.2 (/) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. 0.0 URIBL_BLOCKED ADMINISTRATOR NOTICE: The query to URIBL was blocked. See http://wiki.apache.org/spamassassin/DnsBlocklists#dnsbl-block for more information. [URIs: nabble.com] -1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for sender-domain -0.0 SPF_PASS SPF: sender matches SPF record 1.3 URI_HEX URI: URI hostname has long hexadecimal sequence X-Headers-End: 1Vthe2-0003g8-EM Subject: Re: [Bitcoin-development] DarkWallet Best Practices X-BeenThere: bitcoin-development@lists.sourceforge.net X-Mailman-Version: 2.1.9 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 19 Dec 2013 17:44:24 -0000 --wRRV7LY7NUeQGEoC Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Dec 19, 2013 at 04:04:17PM -0000, Amir Taaki wrote: Looks like for this to actually go to the email lists they need to be in the To: field. > About signing each commit, Linus advises against it: >=20 > http://git.661346.n2.nabble.com/GPG-signing-for-git-commit-td2582986.html >=20 > "Btw, there's a final reason, and probably the really real one. Signing > each commit is totally stupid. It just means that you automate it, and you > make the signature worth less. It also doesn't add any real value, since > the way the git DAG-chain of SHA1's work, you only ever need _one_ > signature to make all the commits reachable from that one be effectively > covered by that one. So signing each commit is simply missing the point." >=20 > What do you reckon? His point is valid, but it's valid in the context of how Linux development is done, not Bitcoin. The key difference being that Linus and other kernel developers have a model where code is passed around on mailing lists and between developers rather than stored on untrustworthy third-parties like github. For instance typically someone will submit a patch to the kernel development mailing list, example: http://www.mail-archive.com/linux-kernel@vger.kernel.org/msg558841.html That patch isn't signed, and the email itself doesn't have to be PGP signed either. However a trusted maintainer of the relevant subsystem will (in theory) look over the patch carefully and commit it to their personal tree on a secure computer. (in theory) At some point the maintainer will create a *signed* tag on a commit with one or more patches, often many patches, another another maintainer higher in the hierarchy (maybe even Linus) will *merge* that tag into their tree, hopefully checking the signature first! Modern versions of git actually include the tag signature in the merge commit, so the result is signed by the original maintainer; note how this contradicts Linus's email with regard to the idea of separable signatures. Eventually multiple such groups of patches build up and the result is tagged as a release, and that release tag is signed. Accountability in this model rests with maintainers, and source-code stays on a multitude of personal, secure, locations. (in theory) However since we like to use github and tend to get code directly from it our main risk is github (or similar) being compromised. Given that I think we're much better off using per-commit signatures, and in effect continually making the statement "Yes, this commit/merge was really produced by me on my machine, although I may have made a mistake and might not have looked at the code as thoroughly as I maybe should have." The statement *is* weaker than Linus's model of "This signature is Really Official and Stuff and I've carefully checked everything." but I think we're much more interested in getting a strong guarantee on who made the commit than some strong statement about its actual contents - humans are fallible anyway. > Also do you approve of the other link I sent you? >=20 > https://wiki.unsystem.net/index.php/DarkWallet/Negotiation I think you're conflating identities with the messaging layer; focus on the latter and use off-the-shelf identity systems like OpenPGP and SSL certificate authorities. Remember that every new identity system that gets involved is another way for an attacker to MITM attack you; you're better off using whatever the user is using already. --=20 'peter'[:-1]@petertodd.org 00000000000000016a442255c6d15cd6e085991c1efffc9caeff5fc6da14368a --wRRV7LY7NUeQGEoC Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQEcBAEBCAAGBQJSszBmAAoJEBmcgzuo5/CF9UsH/2hNZzAPnuiOvq+7gm+eURgQ P+6G0oU59tECxV827yW+UO1O9f56yLduUqowNgLW1V8iYih52G9hgzp79gvbPBYw Ndq8N3Axw12pIjBWHr+8Y0g4qOqD1yqfCN+209KL+7cxx98Voq5TOZgBuwwb6VoI njflMqSN91jw2ei4kcWXkZJYe7hXI+vTGPFBN0CGAGafL76t4RG6+RGPFll+X4LQ fci1paTjr+oj3Ukcqfl+7a8eJfctNsRKJRROAZz5ebReutDG7rWA3UeVaTxB/UHv osyvYeaNA1FlrLxOy+kKnHvps41XXWapEdweOZTeVRdxAYjNAMEOa83UIOclsJw= =LqlO -----END PGP SIGNATURE----- --wRRV7LY7NUeQGEoC--