[Telepathy] telepathy-spec vs. E2E encryption: round 3

[Cosimo Cecchi]

Hi everyone,

now that a draft of the server part of the TLS interactions API has
landed in telepathy-spec (with support in Gabble and Empathy), it's time
to go back thinking about end-to-end encryption support.

For those interested in previous rounds of discussions, see [1], [2] and
the surrounding threads.

The bulk of my proposal is discussed into deeper detail in this bug
report [3] and in former threads, so I won't repeat it here.

Notable changes since last iteration include:
- make it possible for clients to choose which encryption method they
should use; this way, it should be easier to support things such as OTR
together with XTLS.
- make it possible to upgrade an existing unencrypted channel to an
encrypted one.

At this point, I'd really like to get feedback on whether I'm on the
right path getting this right, before I go ahead and start implementing
the proposal in wocky and telepathy-gabble.

[1]
http://lists.freedesktop.org/archives/telepathy/2009-November/004050.html
[2] http://lists.freedesktop.org/archives/telepathy/2010-May/004564.html
[3] https://bugs.freedesktop.org/show_bug.cgi?id=29904 

Cheers,

Cosimo