Bug description: For each descriptor, its revision counter is the OPE
ciphertext of the number of seconds since the start time of its SRV value.
This bug caused us to confuse the SRV start time in the middle of the lifetime
of a descriptor in some edge-cases, which caused descriptor rejects.
Bug cause: The bug occurs when we fetch a 23:00 consensus after
midnight (e.g. at 00:08 when not all dirauths have fetched the latest 00:00
consensus). In that case, the voting schedule (which was used for SRV start
time calculation) would return a valid-after past-midnight, whereas our
consensus would be pre-midnight, and that would confuse the SRV start time
computation which is used by HS revision counters (because we would reset the
start time of SRV, without rotating descriptors).
Bug fix: We now use our local consensus time to calculate the SRV start time,
instead of the voting schedule. The voting schedule does not work as originally
envisioned in this case, because it was created for voting by dirauths and not
for scheduling stuff on clients.
This commit won't build yet -- it just puts everything in a slightly
more logical place.
The reasoning here is that "src/core" will hold the stuff that every (or
nearly every) tor instance will need in order to do onion routing.
Other features (including some necessary ones) will live in
"src/feature". The "src/app" directory will hold the stuff needed
to have Tor be an application you can actually run.
This commit DOES NOT refactor the former contents of src/or into a
logical set of acyclic libraries, or change any code at all. That
will have to come in the future.
We will continue to move things around and split them in the future,
but I hope this lays a reasonable groundwork for doing so.
