Re: [Social-discuss] Announcing P2P GNU Social

[Ted Smith]

On Sun, 2010-07-11 at 15:33 +0200, Melvin Carvalho wrote:
> 
> 
> On 11 July 2010 06:18, Ted Smith <address@hidden> wrote:
>         
>         On Sun, 2010-07-11 at 11:21 +0900, B. Kip wrote:
>         > Still trying to understand this in detail:
>         >
>         > On Sat, Jul 10, 2010 at 9:46 PM, Blaine Cook
>         <address@hidden> wrote:
>         >         On 10 July 2010 13:26, Ted Smith <address@hidden>
>         wrote:
>         >         > It means that if your server (to be precise, your
>         >         > core) is cracked, or subpoenaed by the
>         MAFIAA/ACTA-Empowered
>         >         Sharing
>         >         > Police, it can give up no data that you haven't
>         already
>         >         decided is
>         >         > public.
>         >         >
>         >         > I don't think that StatusNet GNU Social makes that
>         >         guarantee, even when
>         >         > it comes to private messaging. I would be very
>         happy to be
>         >         wrong.
>         >
>         >
>         >         It doesn't, though servers are free to encrypt the
>         data before
>         >         and/or
>         >         after it's sent. The same applies for email. Two
>         thoughts:
>         >
>         >         1. I welcome experiments using P2P networks for
>         social
>         >         networks, but
>         >         consider the human-level usability concerns. No
>         matter what
>         >         the
>         >         underlying technology is, you need a human-level
>         addressing
>         >         system
>         >         (the acid test for a good addressing scheme is the
>         ability for
>         >         one
>         >         person to be able to write down on a scrap of paper
>         an address
>         >         at
>         >         which someone else can contact them later). If you
>         use
>         >         webfinger (re:
>         >         email-like addresses), you can maintain
>         compatibility with
>         >         mainline
>         >         GNU Social, Status.net, Diaspora (i.e., OStatus),
>         and Google
>         >         Buzz
>         >         while providing forwards-compatibility to stronger
>         >         privacy-based
>         >         networks*.
>         >
>         > From: GNU social - Privatemessaging - Open wiki - Gitorious
>         > http://gitorious.org/social/pages/Privatemessaging:
>         >               * If Bob hasn’t authenticated against Alice’s
>         server,
>         >                 then Bob’s server goes through the Webfinger
>         auth
>         >                 process, generating a shared secret. If he
>         already
>         >                 has, he’ll already have such a secret.
>         >               * Bob’s server uses the shared secret from the
>         Webfinger
>         >                 auth process to retrieve Alice’s message.
>         > So, as I understand it, this shared secret is simply a way
>         of ensuring
>         > that Bob is really Bob and Alice is really Alice, and that
>         they know
>         > eachother, not a key that is used to encrypt messages
>         between Alice
>         > and Bob- correct?
>         
>         
>         I believe that's correct. I'm not entirely sure what "the
>         Webfinger auth
>         process" is here. A cursory look at Webfinger doesn't indicate
>         what that
>         is. I assume it is something that Bob's server uses to prove
>         that it
>         hosts Bob's account, at which point Alice's server sends Bob's
>         server
>         the message.
>         
>         > If you go this far why not take the extra step of
>         encryption?  Is that
>         > a whole lot more complicated to do?  What process are you
>         using to
>         > authenticate?  Are you making use of public keys shared
>         through
>         > Webfinger?
>         
>         
>         There's not really any point of encryption if your key
>         material is
>         stored on an untrusted server.
>         
>         I'm not really sure if you're asking questions about Statusnet
>         GNU
>         Social or P2P GNU Social, but in P2P GNU Social, there's no
>         need for
>         authentication, because the messages are encrypted end-to-end.
>         Like all
>         other content, Alice notifies Bob of a message, and Bob pulls
>         the
>         message. If anyone else is scraping Alice's core and finds the
>         URL that
>         Bob uses to pull Alice's message, they can have it - as long
>         as the
>         protocols Alice and Bob picked to use in OpenPGP are secure
>         (probably
>         RSA and AES), there is not much hope of that person obtaining
>         the
>         message.
> 
> Yeah, nice.  I've often thought person to person sharing can be
> encrypted simply using the next party's public key (GPG or X.509)
> 
> For group sharing you can add another optimization of a group sharing
> an aes 256 key.  Of course you're only as strong as your weakest link,
> but it's a good start.
> 
We get this for free with OpenPGP. It encrypts the data with a symmetric
cipher, and encrypts the key for that with the asymmetric cipher.

> With FOAF it's pretty easy to associate a public key with a profile (a
> few lines of cut and paste) which is also the basis/simplicity of FOAF
> +SSL 
> 
> The elegance of this system is that to get a user's public key, you
> just need to lookup the webpage, which is something that's almost
> trivial to do.  
> 
> With webfinger it's a bit harder to get information out of the email
> address, you'd normally have to deploy a server to specially do this.
> It's always nice to be able to get new information from an identifier,
> IMHO it's an unnecessary step, but i dont have a huge issue with
> people that want to do this, and can see it's necessary for many of
> the large webmail providers to finally get into the interop game.

You'd have to set up a server to get information out of FOAF, right? You
need some way to download the information. Webfinger only involves
webpage lookups.

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