From: Eric Voskuil <eric@voskuil•org>
To: Paul Puey <paul@airbitz•co>, William Swanson <william@airbitz•co>
Cc: Bitcoin Dev <bitcoin-development@lists•sourceforge.net>
Subject: Re: [Bitcoin-development] Proposal for P2P Wireless (Bluetooth LE) transfer of Payment URI
Date: Thu, 05 Feb 2015 17:05:23 -0800 [thread overview]
Message-ID: <54D41353.5050205@voskuil.org> (raw)
In-Reply-To: <CEB250A3-9014-4AF3-AEB7-E78BE19BF2F5@airbitz.co>
[-- Attachment #1: Type: text/plain, Size: 3126 bytes --]
On 02/05/2015 04:49 PM, Paul Puey wrote:
> The trust can be considered bootstrapped by visual verification of the
> address prefix.
Another (unspendable) address can trivially match the prefix. Imagine
someone walking around in a mall with a phone in the pocket with a
malicious app, just disrupting business by causing money to be burned.
Manual verification doesn't fix this attack.
> If we are really concerned about someone jamming a Bluetooth signal
> in a coffeeshop then the UI can encourage verification of the prefix.
I don't think it would be great to constrain a standard implementation
to low cost purchases or the need for manual verification, but again
manual prefix verification isn't actually a solution.
> Much like how regular Bluetooth requires 'pairing' via entering a 4-6
> digit code.
An appeal to the security of BT bootstrapping isn't exactly flattering.
You know I love Airbitz, and I know you guys are extremely privacy
conscious. I personally would have no problem using this feature under
certain circumstances. My question is only whether it would be wise to
standardize on the proposal as-is.
e
> On Feb 5, 2015, at 3:46 PM, Eric Voskuil <eric@voskuil•org
> <mailto:eric@voskuil•org>> wrote:
>
> On 02/05/2015 03:36 PM, MⒶrtin HⒶboⓋštiak wrote:
>>> A BIP-70 signed payment request in the initial broadcast can resolve the
>>> integrity issues, but because of the public nature of the broadcast
>>> coupled with strong public identity, the privacy compromise is much
>>> worse. Now transactions are cryptographically tainted.
>>>
>>> This is also the problem with BIP-70 over the web. TLS and other
>>> security precautions aside, an interloper on the communication, desktop,
>>> datacenter, etc., can capture payment requests and strongly correlate
>>> transactions to identities in an automated manner. The payment request
>>> must be kept private between the parties, and that's hard to do.
>>
>> What about using encryption with forward secrecy? Merchant would
>> generate signed request containing public ECDH part, buyer would send
>> back transaction encrypted with ECDH and his public ECDH part. If
>> receiving address/amount is meant to be private, use commit protocol
>> (see ZRTP/RedPhone) and short authentication phrase (which is hard to
>> spoof thanks to commit protocol - see RedPhone)?
>
> Hi Martin,
>
> The problem is that you need to verify the ownership of the public key.
> A MITM can substitute the key. If you don't have verifiable identity
> associated with the public key (PKI/WoT), you need a shared secret (such
> as a secret phrase). But the problem is then establishing that secret
> over a public channel.
>
> You can bootstrap a private session over the untrusted network using a
> trusted public key (PKI/WoT). But the presumption is that you are
> already doing this over the web (using TLS). That process is subject to
> attack at the CA. WoT is not subject to a CA attack, because it's
> decentralized. But it's also not sufficiently deployed for some scenarios.
>
> e
>
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 473 bytes --]
next prev parent reply other threads:[~2015-02-06 1:05 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-02-05 20:06 Paul Puey
2015-02-05 20:28 ` Mike Hearn
2015-02-05 20:37 ` Paul Puey
2015-02-05 20:43 ` Mike Hearn
2015-02-05 20:44 ` Eric Voskuil
2015-02-05 20:50 ` Mike Hearn
2015-02-05 20:59 ` Eric Voskuil
2015-02-05 21:19 ` Brian Hoffman
2015-02-05 21:23 ` Eric Voskuil
2015-02-05 21:36 ` Mike Hearn
2015-02-05 21:46 ` Eric Voskuil
2015-02-05 22:07 ` Paul Puey
2015-02-05 22:10 ` Eric Voskuil
2015-02-05 22:49 ` Roy Badami
2015-02-05 23:22 ` MⒶrtin HⒶboⓋštiak
2015-02-05 23:02 ` William Swanson
2015-02-05 23:34 ` Roy Badami
2015-02-05 23:59 ` Eric Voskuil
2015-02-06 8:59 ` Roy Badami
2015-02-06 9:13 ` Eric Voskuil
2015-02-06 0:58 ` Paul Puey
2015-02-05 23:22 ` Eric Voskuil
2015-02-05 23:36 ` MⒶrtin HⒶboⓋštiak
2015-02-05 23:46 ` Eric Voskuil
2015-02-06 0:04 ` MⒶrtin HⒶboⓋštiak
2015-02-06 0:22 ` Eric Voskuil
2015-02-06 0:36 ` Martin Habovštiak
2015-02-06 1:29 ` Eric Voskuil
2015-02-06 9:07 ` MⒶrtin HⒶboⓋštiak
2015-02-10 16:55 ` Eric Voskuil
2015-02-10 17:16 ` MⒶrtin HⒶboⓋštiak
2015-02-10 17:56 ` Eric Voskuil
2015-02-06 0:49 ` Paul Puey
2015-02-06 0:50 ` Martin Habovštiak
2015-02-06 1:05 ` Eric Voskuil [this message]
2015-02-06 2:09 ` Paul Puey
2015-02-05 22:02 ` Paul Puey
2015-02-05 22:01 ` Paul Puey
2015-02-05 22:05 ` Eric Voskuil
2015-02-05 22:08 ` Paul Puey
-- strict thread matches above, loose matches on Subject: below --
2015-02-05 8:01 Paul Puey
2015-02-05 13:46 ` Andreas Schildbach
2015-02-05 13:57 ` Mike Hearn
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=54D41353.5050205@voskuil.org \
--to=eric@voskuil$(echo .)org \
--cc=bitcoin-development@lists$(echo .)sourceforge.net \
--cc=paul@airbitz$(echo .)co \
--cc=william@airbitz$(echo .)co \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox