Rustls uses ring, which uses code from BoringSSL, which derived from
OpenSSL before OpenSSL changed their license. So ring is currently
under 3BSD/SSLEay licenses, which aren't GPL-compatible, which may
be a problem for some people.
See #493.
The `DirBootstrapStatus` type now exposes a blockage() method to
return an `Option<DirBlockage>`.
The blockage types reported are more low-level than I'd like, but
they are IMO good enough for now: we'll want to get experience with
actual vs hypothetical problems before we refine them.
A "reset" happens whenever we have to start a download attempt over
-- either because we ran out of retries, or we found something wrong
with the consensus after fetching certificates.
An "error" happens when we have a recoverable error from one or more
directory sources.
A "stall" happens whenever a round of downloads or cache loads leads
to no change in the status.
We don't yet use this as part of our status reporting.
Previously we used the "if-modified-since" time associated with the
consensus download, and/or the "valid-after" time in the consensus
attempt, to put multiple attempts into sequence, and to tell one
from another. But that approach was always a kludge, and will soon
get more unreliable as the DirStatus logic gets a bit more complex.
With this commit, we change separate download attempts to be
identified with an AttemptId that increments whenever we decide to
get a different directory from the one we have. IMO this new code
is _much_ cleaner.
This is about to become only a _part_ of what defines a DirStatus: a
DirStatus will also include a reset count, and some kind of info
about how long we've gone without progress.
These need to be optional: they improve performance by shifting to
asm implementations, which may not be everybody's idea of good practice.
These are not 'pure' features, since they select one implementation
but disable another. Therefore they don't go in `full`.
Closes#441.
This change also means that we need to create the handle and scheduler
earlier in the process of creating the DirMgr. If we don't, we won't
have a way to manage the task before bootstrap() returns.
The "full" feature is a catch-all for all features, _except_:
* Those that select a particular implementation (like
tor-llcrypto/with-openssl) or build flag (like "static")
* Those that are experimental or unstable (like "experimental-api")
* Those that are testing-only.
This change (not yet exposed as an API) will let the TorClient have
a `TaskHandle` corresponding to the directory task, letting it
make the directory task dormant as needed.
Nick Mathewson
Ian Jackson
eta