From mboxrd@z Thu Jan 1 00:00:00 1970 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 1XSSth-0007Go-HF for bitcoin-development@lists.sourceforge.net; Fri, 12 Sep 2014 15:36:29 +0000 Received-SPF: pass (sog-mx-2.v43.ch3.sourceforge.com: domain of gmail.com designates 209.85.214.179 as permitted sender) client-ip=209.85.214.179; envelope-from=mh.in.england@gmail.com; helo=mail-ob0-f179.google.com; Received: from mail-ob0-f179.google.com ([209.85.214.179]) by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1XSStg-0004IC-EG for bitcoin-development@lists.sourceforge.net; Fri, 12 Sep 2014 15:36:29 +0000 Received: by mail-ob0-f179.google.com with SMTP id uz6so692057obc.24 for ; Fri, 12 Sep 2014 08:36:18 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.182.181.3 with SMTP id ds3mr9009453obc.11.1410536178483; Fri, 12 Sep 2014 08:36:18 -0700 (PDT) Sender: mh.in.england@gmail.com Received: by 10.76.22.108 with HTTP; Fri, 12 Sep 2014 08:36:18 -0700 (PDT) In-Reply-To: References: Date: Fri, 12 Sep 2014 17:36:18 +0200 X-Google-Sender-Auth: 09bf43kZf_1eztRw2KjEnEh3ERM Message-ID: From: Mike Hearn To: Andreas Schildbach Content-Type: multipart/alternative; boundary=089e01182856dc89c70502e00bd0 X-Spam-Score: -0.5 (/) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. -1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for sender-domain 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (mh.in.england[at]gmail.com) -0.0 SPF_PASS SPF: sender matches SPF record 1.0 HTML_MESSAGE BODY: HTML included in message 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature X-Headers-End: 1XSStg-0004IC-EG Cc: Bitcoin Dev Subject: Re: [Bitcoin-development] BIP72 amendment proposal 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: Fri, 12 Sep 2014 15:36:29 -0000 --089e01182856dc89c70502e00bd0 Content-Type: text/plain; charset=UTF-8 Your example doesn't have an address in it at all, so isn't compatible with non-BIP70 wallets. Maybe for QRcodes specifically there are no longer any such wallets out there. For clickable links it can still be an issue. > I thought SHA1 has a bad reputation these days, and we don't save much > by using it. I don't know anything about Murmur. MD5 is clearly broken. > What hash function would you recommend? > Can just truncate SHA256, I think. > It is. People can't check names. People don't want to check names. > Their wallet checks the name, though. It sees: bitcoin:1AbCd?r=https://bitpay.com/r/12345 and the wallet verifies that the presented certificate is for CN=bitpay.com > People can't get certificates for lots of reasons. X.509 is centralized. > X.509 has had serious security issues in the past. And shit continues to > happen. > Well, I wrote an article that argues with this PoV: https://medium.com/@octskyward/why-you-think-the-pki-sucks-b64cf5912aa7 No disagreement that it's a more complex mechanism. But seeing as we end up depending on it anyway the moment you load any kind of web page to find out the URI, adding another mechanism only increases complexity, it doesn't remove any. Sure. But signing is harder than just calculating a hash. Well, again, it saves qrcode bytes. You don't have to include a dedicated hash. The existing address hash can double up as both a backwards compatibility measure, and also an auth mechanism. --089e01182856dc89c70502e00bd0 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Your example doesn't have an address in it at all, so isn't compat= ible with non-BIP70 wallets. Maybe for QRcodes specifically there are no lo= nger any such wallets out there. For clickable links it can still be an iss= ue.
=C2=A0
I thought SHA1 has a bad reputat= ion these days, and we don't save much
by using it. I don't know anything about Murmur. MD5 is clearly broken.=
What hash function would you recommend?

Can just truncate SHA256, I think.
=C2=A0
= It is. People can't check names. People don't want to check names.<= br>

Their wallet checks the name, though. I= t sees:

bitcoin:1AbCd?r=3Dhttps://bitpay.com/r/12345

and = the wallet verifies that the presented certificate is for CN=3Dbitpay.com
=C2=A0
People can't get certificates for lots of reasons. X.509 is centralized= .
X.509 has had serious security issues in the past. And shit continues to happen.

Well, I wrote an article that a= rgues with this PoV:


<= /div>
No disagreement that it's a more complex mechanism. But seein= g as we end up depending on it anyway the moment you load any kind of web p= age to find out the URI, adding another mechanism only increases complexity= , it doesn't remove any.

Sure. But= signing is harder than just calculating a hash.

Well, again, it saves qrcode bytes. You don't have to include a d= edicated hash. The existing address hash can double up as both a backwards = compatibility measure, and also an auth mechanism.=C2=A0
<= /div> --089e01182856dc89c70502e00bd0--