[messaging] Zero knowledge proofs of passport

[Trevor Perrin]

On Sat, Jul 26, 2014 at 7:43 AM, Mike Hearn <mike at plan99.net> wrote:
> Pond is a great advance for secure messaging, but it suffers from the fact
> that I can't send someone a cold intro if they don't already know me. For
> that reason it does not solve the Snowden/Greenwald problem.
>
> Pond users do have email-address like things and servers could receive and
> store arbitrary messages: it's only the "forward secure or nothing" policy
> that forbids this.

No, Pond senders must authenticate their message with a
recipient-provided secret or the recipient's mailbox will reject it.
See:

https://moderncrypto.org/mail-archive/messaging/2014/000409.html

> Snowden may not have known Greenwald's email address
> at the start, he just knew he wanted to talk to "an American guy with the
> name Glenn Greenwald, who writes this particular blog"

If your use case is "secure key lookup for a well-known journalist", I
think that's easily solved by the reporter posting his public key, key
fingerprint, and/or SecureDrop/GlobalLeaks hidden-service address on
his HTTPS website, twitter, etc.

Trusting national passport agencies seems wrong for this use case.


Trevor