GCC added an implicit-fallthrough warning a while back, where it
would complain if you had a nontrivial "case:" block that didn't end
with break, return, or something like that.  Clang recently added
the same thing.

GCC, however, would let you annotate a fall-through as intended by
any of various magic "/* fall through */" comments.  Clang, however,
only seems to like "__attribute__((fallthrough))".  Fortunately, GCC
accepts that too.

A previous commit in this branch defined a FALLTHROUGH macro to do
the right thing if GNUC is defined; here we replace all of our "fall
through" comments with uses of that macro.

This is an automated commit, made with the following perl one-liner:

  #!/usr/bin/perl -i -p
  s#/\* *falls? ?thr.*?\*/#FALLTHROUGH;#i;

This macro defers to __attribute__((fallthrough)) on GCC (and
clang).  Previously we had been using GCC's magic /* fallthrough */
comments, but clang very sensibly doesn't accept those.

Since not all compiler recognize it, we only define it when our
configure script detects that it works.

Part of a fix for 34078.

Copy required DLLs to test and app, before running tor's tests.

This ensures that tor.exe and test*.exe use the correct version of each
DLL. This fix is not required, but we hope it will avoid DLL search
issues in future.

Closes bug 33673; bugfix on 0.3.4.2-alpha.

For example, "TOR_SKIP_TESTCASES=crypto/.. ./src/test/test" will run
the tests and suppress all the "crypto/" tests.  You could get the
same effect by running "./src/test/test :crypto/..", but that can be
harder to arrange from CI.

Part of a fix/workaround for 33643.

George Kadianakis authored Feb 11, 2020 and Nick Mathewson committed Mar 17, 2020

Given that ed25519 public key validity checks are usually not needed
and (so far) they are only necessary for onion addesses in the Tor
protocol, we decided to fix this specific bug instance without
modifying the rest of the codebase (see below for other fix
approaches).

In our minimal fix we check that the pubkey in
hs_service_add_ephemeral() is valid and error out otherwise.

In the openssl that I have, it should be safe to only check the size
of n.  But if I'm wrong, or if other openssls work differently, we
should check whether any of the fields are too large.

Issue spotted by Teor.

When a Travis chutney job fails, use chutney's new "diagnostics.sh" tool
to produce detailed diagnostic output.

Closes ticket 32792.

(Deep, deep thanks to Taylor for reminding me to test this!)

Although OpenSSL before 1.1.1 is no longer supported, it's possible
that somebody is still using it with 0.3.5, so we probably shouldn't
break it with this fix.

For a bridge configured with a pluggable transport, the transport name is
used, with the IP address, for the GeoIP client cache entry.

However, the DoS subsystem was not aware of it and always passing NULL when
doing a lookup into the GeoIP cache.

This resulted in bridges with a PT are never able to apply DoS defenses for
newly created connections.

Fixes #33491

Signed-off-by: David Goulet <dgoulet@torproject.org>

Putting the slowest jobs first takes full advantage of Travis
concurrency.

Closes 33194.

Part of 33194.

The job was previously set to fast_finish / allow_failure, to
speed up the build.

Closes ticket 33195.

Alexander Færøy authored Jan 15, 2020 and teor committed Feb 12, 2020

This patch ensures that we always lowercase the BridgeDistribution from
torrc in descriptors before submitting it.

See: https://bugs.torproject.org/32753

Private-key validation is fairly expensive for long keys in openssl,
so we need to avoid it sooner.

We introduced these BUG() checks in b0ddaac0 to prevent a
recurrence of bug 23690.  But there's a report of the BUG() message
getting triggered and filling up the disk.  Let's change it to
IF_BUG_ONCE().

Fixes bug 33093; bugfix on 0.3.2.2-alpha.

Stop allowing failures on the Travis CI stem tests job. It looks like
all the stem hangs we were seeing are now fixed, but let's make sure we
see them if they happen again.

Closes ticket 33075.