Received: from sog-mx-3.v43.ch3.sourceforge.com ([172.29.43.193] helo=mx.sourceforge.net) by sfs-ml-1.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1VLs80-0001S1-GA for bitcoin-development@lists.sourceforge.net; Tue, 17 Sep 2013 10:03:28 +0000 Received-SPF: pass (sog-mx-3.v43.ch3.sourceforge.com: domain of gmail.com designates 209.85.214.47 as permitted sender) client-ip=209.85.214.47; envelope-from=mh.in.england@gmail.com; helo=mail-bk0-f47.google.com; Received: from mail-bk0-f47.google.com ([209.85.214.47]) by sog-mx-3.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1VLs7y-0000jh-Cp for bitcoin-development@lists.sourceforge.net; Tue, 17 Sep 2013 10:03:28 +0000 Received: by mail-bk0-f47.google.com with SMTP id mx12so2016747bkb.6 for ; Tue, 17 Sep 2013 03:03:19 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.205.64.9 with SMTP id xg9mr1217547bkb.30.1379412199515; Tue, 17 Sep 2013 03:03:19 -0700 (PDT) Sender: mh.in.england@gmail.com Received: by 10.204.72.69 with HTTP; Tue, 17 Sep 2013 03:03:19 -0700 (PDT) In-Reply-To: <3B80F433-9039-459B-BC96-A56786DEF6C3@grabhive.com> References: <9179D240-EE7E-41A4-AA59-7C96246D8CFB@grabhive.com> <82E79EB0-49D6-492A-AE4A-6A786C7B0AAA@grabhive.com> <3B80F433-9039-459B-BC96-A56786DEF6C3@grabhive.com> Date: Tue, 17 Sep 2013 12:03:19 +0200 X-Google-Sender-Auth: fe1hZBYLkN-b0tHrBLaN-3WujYs Message-ID: From: Mike Hearn To: Wendell Content-Type: multipart/alternative; boundary=bcaec53fee9d26db3f04e6916e3d 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: 1VLs7y-0000jh-Cp Cc: Bitcoin Dev Subject: Re: [Bitcoin-development] Simple contacts exchange (was: Social network integration (brainstorm)) 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: Tue, 17 Sep 2013 10:03:28 -0000 --bcaec53fee9d26db3f04e6916e3d Content-Type: text/plain; charset=UTF-8 You can prove ownership of a private key by signing a challenger-generated nonce with the public part and giving the signature back to the challenger - same as with any asymmetric crypto system. As I already noted, the payment protocol is designed to solve that problem. You could design a BIP that extended the payment protocol to include information about the person who generated it. On Tue, Sep 17, 2013 at 11:30 AM, Wendell wrote: > Couple of things I just thought about: > > 1- Presume server should only sweep with two (or more, see below) > revocation certificates being present > 2- Need to insert something in the flow so that Alice can verify that the > uploaded key is actually Bob's (and perhaps vise-versa, given an extremely > dedicated attacker with a fast connection?). > > Is there a way to do #2 without creating yet another transaction? > Admittedly I am still really puzzled about the accessibility of public keys > in Bitcoin! > > Please remember that the idea is to have two wallets securely exchange a > packet of metadata about a transaction beyond the scope of Bitcoin itself > (a name, perhaps a small photo, etc) in order to increase usability. This > will be my last post here on the topic except to reply in case anyone else > contributes. > > -wendell > > grabhive.com | twitter.com/grabhive | gpg: 6C0C9411 > > On Sep 16, 2013, at 4:05 PM, Wendell wrote: > > > Luke pointed out that we should not be inserting extraneous data into > the blockchain, so this sounds like the best option, Eric. > > > > I'm under the impression that a Bitcoin user Alice cannot see the actual > public key of Bitcoin user Bob, so if we had Hive store metadata on a > server relating to a given transaction ID, I would not be able to use those > public keys key to encrypt. Is this a misunderstanding or is it correct? > > > > Assuming it is correct, the best that I could come up with was storing > the transaction ID with a _fresh_ public key on a server, each time a > transfer is made. Altogether it looks like this: > > > > - Alice generates a new keypair & revocation certificate for the > transaction > > - Alice makes a Bitcoin transaction to Bob > > - Alice sends the transaction ID plus the new public key to server > > - Bob receives the Bitcoin transaction > > - Bob generates a new keypair & revocation certificate > > - Bob does a transaction ID lookup on the server, receives Alice's > public key, sends his own new one > > - Bob encrypts his user metadata against Alice's new key > > - Alice downloads and decrypts Bob's metadata > > - Alice uploads her revocation certificate > > - Alice uploads her own metadata > > - Bob downloads Alice's metadata > > - Bob uploads his revocation certificate > > - (Server removes all keys with revocation certificates) > > > > I presume going the extra mile to generate new keys for each transaction > is helpful for privacy? > > > > The above seems rather inelegant to me. I really don't like that clients > (wallets) are going to be beating down the server all the time checking for > keys, or that there is a possibility of a desynchronization so severe that > the user receives the data much too late for it to be useful. But, I > suppose it can work. > > > > Another thing I'm considering is Alice/Bob validating each other. I > suppose we should include some kind of code that we encourage people to > read to each other over the phone or some other medium, to ensure that "it > really is Alice", before (for example) returning money to a very > legit-looking personage. > > > > Any other thoughts? I would love to do this without using any servers at > all ("serverless keyserver", anyone?), but I am not quite sure how. > > > > -wendell > > > > grabhive.com | twitter.com/grabhive | gpg: 6C0C9411 > > > > On Sep 7, 2013, at 12:47 AM, Eric Lombrozo wrote: > > > >> Why not just use the transaction hash itself for the lookup? Also, > presumably you'd want to encrypt the data so that only the recipient of the > transaction can do this lookup. > >> > >> -Eric > >> > >> On Sep 6, 2013, at 8:07 AM, Wendell wrote: > >> > >>> Hi all, > >>> > >>> We're thinking about ways of automatically exchanging contact details > between wallets, in order to encourage the proliferation of identifiable > names and photos rather than long and hard-to-verify addresses. > >>> > >>> The simplest version goes like this: > >>> > >>> 2 BTC Bitcoin is sent to someone, and a data lookup hash is inserted > into the transaction. When it arrives on the other end, it is indeed looked > up, and instead of being presented with a dialogue that says "you received > 2 BTC from 13Y94z43Nbbb6wevRyk82CeDoYQ5S28zmA", it's "You received 2 BTC > from Frank Jones" including a nice photo. > >>> > >>> Now. We can simply delete this data in reference to the transaction ID > after it happens (or delete it after a time), but is there any more > decentralized way to do it? I would prefer us to run no dedicated servers > that would ever put us in a position of being coerced into giving data, or > otherwise altering our system to store it. > >>> > >>> Any thoughts about this? > >>> > >>> -wendell > >>> > >>> grabhive.com | twitter.com/grabhive | gpg: 6C0C9411 > >>> > >>> > ------------------------------------------------------------------------------ > >>> Learn the latest--Visual Studio 2012, SharePoint 2013, SQL 2012, more! > >>> Discover the easy way to master current and previous Microsoft > technologies > >>> and advance your career. Get an incredible 1,500+ hours of step-by-step > >>> tutorial videos with LearnDevNow. Subscribe today and save! > >>> > http://pubads.g.doubleclick.net/gampad/clk?id=58041391&iu=/4140/ostg.clktrk_______________________________________________ > >>> Bitcoin-development mailing list > >>> Bitcoin-development@lists.sourceforge.net > >>> https://lists.sourceforge.net/lists/listinfo/bitcoin-development > > > > ------------------------------------------------------------------------------ > LIMITED TIME SALE - Full Year of Microsoft Training For Just $49.99! > 1,500+ hours of tutorials including VisualStudio 2012, Windows 8, > SharePoint > 2013, SQL 2012, MVC 4, more. BEST VALUE: New Multi-Library Power Pack > includes > Mobile, Cloud, Java, and UX Design. Lowest price ever! Ends 9/20/13. > http://pubads.g.doubleclick.net/gampad/clk?id=58041151&iu=/4140/ostg.clktrk > _______________________________________________ > Bitcoin-development mailing list > Bitcoin-development@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/bitcoin-development > --bcaec53fee9d26db3f04e6916e3d Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
You can prove ownership of a private key by signing a chal= lenger-generated nonce with the public part and giving the signature back t= o the challenger - same as with any asymmetric crypto system.

As I already noted, the payment protocol is designed to solve that pro= blem. You could design a BIP that extended the payment protocol to include = information about the person who generated it.


On Tue, Sep 17, 2013 at 11:30 AM, Wendel= l <w@grabhive.com> wrote:
Couple of things I just thought about:

1- Presume server should only sweep with two (or more, see below) revocatio= n certificates being present
2- Need to insert something in the flow so that Alice can verify that the u= ploaded key is actually Bob's (and perhaps vise-versa, given an extreme= ly dedicated attacker with a fast connection?).

Is there a way to do #2 without creating yet another transaction? Admittedl= y I am still really puzzled about the accessibility of public keys in Bitco= in!

Please remember that the idea is to have two wallets securely exchange a pa= cket of metadata about a transaction beyond the scope of Bitcoin itself (a = name, perhaps a small photo, etc) in order to increase usability. This will= be my last post here on the topic except to reply in case anyone else cont= ributes.

-wendell

grabhive.com | twitter.com/grabhive | gpg: 6C0C9411

On Sep 16, 2013, at 4:05 PM, = Wendell wrote:

> Luke pointed out that we should not be inserting extraneous data into = the blockchain, so this sounds like the best option, Eric.
>
> I'm under the impression that a Bitcoin user Alice cannot see the = actual public key of Bitcoin user Bob, so if we had Hive store metadata on = a server relating to a given transaction ID, I would not be able to use tho= se public keys key to encrypt. Is this a misunderstanding or is it correct?=
>
> Assuming it is correct, the best that I could come up with was storing= the transaction ID with a _fresh_ public key on a server, each time a tran= sfer is made. Altogether it looks like this:
>
> - Alice generates a new keypair & revocation certificate for the t= ransaction
> - Alice makes a Bitcoin transaction to Bob
> - Alice sends the transaction ID plus the new public key to server
> - Bob receives the Bitcoin transaction
> - Bob generates a new keypair & revocation certificate
> - Bob does a transaction ID lookup on the server, receives Alice's= public key, sends his own new one
> - Bob encrypts his user metadata against Alice's new key
> - Alice downloads and decrypts Bob's metadata
> - Alice uploads her revocation certificate
> - Alice uploads her own metadata
> - Bob downloads Alice's metadata
> - Bob uploads his revocation certificate
> - (Server removes all keys with revocation certificates)
>
> I presume going the extra mile to generate new keys for each transacti= on is helpful for privacy?
>
> The above seems rather inelegant to me. I really don't like that c= lients (wallets) are going to be beating down the server all the time check= ing for keys, or that there is a possibility of a desynchronization so seve= re that the user receives the data much too late for it to be useful. But, = I suppose it can work.
>
> Another thing I'm considering is Alice/Bob validating each other. = I suppose we should include some kind of code that we encourage people to r= ead to each other over the phone or some other medium, to ensure that "= ;it really is Alice", before (for example) returning money to a very l= egit-looking personage.
>
> Any other thoughts? I would love to do this without using any servers = at all ("serverless keyserver", anyone?), but I am not quite sure= how.
>
> -wendell
>
> grabhive.com | <= a href=3D"http://twitter.com/grabhive" target=3D"_blank">twitter.com/grabhi= ve | gpg: 6C0C9411
>
> On Sep 7, 2013, at 12:47 AM, Eric Lombrozo wrote:
>
>> Why not just use the transaction hash itself for the lookup? Also,= presumably you'd want to encrypt the data so that only the recipient o= f the transaction can do this lookup.
>>
>> -Eric
>>
>> On Sep 6, 2013, at 8:07 AM, Wendell <w@grabhive.com> wrote:
>>
>>> Hi all,
>>>
>>> We're thinking about ways of automatically exchanging cont= act details between wallets, in order to encourage the proliferation of ide= ntifiable names and photos rather than long and hard-to-verify addresses. >>>
>>> The simplest version goes like this:
>>>
>>> 2 BTC Bitcoin is sent to someone, and a data lookup hash is in= serted into the transaction. When it arrives on the other end, it is indeed= looked up, and instead of being presented with a dialogue that says "= you received 2 BTC from 13Y94z43Nbbb6wevRyk82CeDoYQ5S28zmA", it's = "You received 2 BTC from Frank Jones" including a nice photo.
>>>
>>> Now. We can simply delete this data in reference to the transa= ction ID after it happens (or delete it after a time), but is there any mor= e decentralized way to do it? I would prefer us to run no dedicated servers= that would ever put us in a position of being coerced into giving data, or= otherwise altering our system to store it.
>>>
>>> Any thoughts about this?
>>>
>>> -wendell
>>>
>>> grabhive.com= | twitter.co= m/grabhive | gpg: 6C0C9411
>>>
>>> --------------------------------------------------------------= ----------------
>>> Learn the latest--Visual Studio 2012, SharePoint 2013, SQL 201= 2, more!
>>> Discover the easy way to master current and previous Microsoft= technologies
>>> and advance your career. Get an incredible 1,500+ hours of ste= p-by-step
>>> tutorial videos with LearnDevNow. Subscribe today and save! >>> http://pubads.g.doubleclick.net/gampad/clk?id=3D580= 41391&iu=3D/4140/ostg.clktrk___________________________________________= ____
>>> Bitcoin-development mailing list
>>> B= itcoin-development@lists.sourceforge.net
>>> https://lists.sourceforge.net/lists/listin= fo/bitcoin-development


---------------------------------------------------------------------------= ---
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