[messaging] MITM-safe communication w/o authentication possible?

[Jeff Burdges]

On Wed, 2015-12-02 at 07:05 -0500, Karl wrote:
> I guess I'm just saying that the number of faces we have to compare
> to
> live normally implies that we can easily distinguish a lot more
> information for this specific task than for other tasks. 

I have not looked at the research, but individuals vary wildly in their
ability to remember different sorts of information.  And not everyone
is great at faces.  There are probably going to be people who remember
a phrase, poem, or very short story generated by a fixed markov engine
much better than an abstract image.  

There was a discussion of using visualizations to protect users against
.onion fishing attacks* on tor-dev here : 
https://lists.torproject.org/pipermail/tor-dev/2015-August/thread.html#
9302
In that conversation, there was a feeling that (a) different people
might need different visualizations and (b) a per browser salt should
help lots.

One could bind a regular non-generated image with a public key, in such
a way that the image acted as a per contact salt instead of a per
browser salt.  If your contact did not care about anonymity, then you'
might see a real photo of them, an abstract photo, possibly arranged
around them, and a short story.  Basically, a lol-contact key
remembering and description tool. 

Jeff


*  In TBB's situation, there is an easy way to record identities one
intentionally visits using browser bookmarks, but these do not fare so
well when visiting another url on the same site using an href from
another site.  It'd be tricky to expand this as the Tor community is
loath to make Tor Browser remember more about the user's browsing
patterns. 
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