[messaging] countering active attacks against autocrypt messaging

[holger krekel]

Those interested in e-mail and more general messenging encryption 
security might find it interesting to read the countermitm-0.9.1 release 
of the "countering active attacks against Autocrypt" effort:

    https://countermitm.readthedocs.io 

It discusses new key verification protocols which are implemented
as a "Labs" feature in https://delta.chat, released to F-droid.
It also discusses key consistency research and implementation 
efforts around https://claimchain.github.io/ . 

While the doc deliberately focuses on Autocrypt e-mail encryption 
(https://autocrypt.org) most of the results can likely be applied 
to other messengers.  

The research effort is ongoing and we'd welcome feedback 
and PRs against https://github.com/nextleap-project/countermitm
We want to release a 1.0 version of this doc end of the year. 
Part of the work has been funded by the European Commission
but lots is happening independently in various communities. 

holger