Fixes a possible root cause of 11553 by only making 64 attempts at
most to pick a circuitID. Previously, we would test every possible
circuit ID until we found one or ran out.
This algorithm succeeds probabilistically. As the comment says:
This potentially causes us to give up early if our circuit ID
space is nearly full. If we have N circuit IDs in use, then we
will reject a new circuit with probability (N / max_range) ^
MAX_CIRCID_ATTEMPTS. This means that in practice, a few percent
of our circuit ID capacity will go unused.
The alternative here, though, is to do a linear search over the
whole circuit ID space every time we extend a circuit, which is
not so great either.
This makes new vs old clients distinguishable, so we should try to
batch it with other patches that do that, like 11438.
We are searching @CONFDIR@ before $HOME, but the documentation
implied otherwise.
I screwed this up in f5e86bcd6c, when I
first documented the $HOME/.torrc possibility.
Fix for bug 9213; bugfix on 0.2.3.18-rc.
See 1d2179bc90 in master for details.
"""
Fall back to registered country if necessary.
When extracting geoip and geoip6 files from MaxMind's GeoLite2 Country
database, we only look at country->iso_code which is the two-character ISO
3166-1 country code of the country where MaxMind believes the end user is
located.
But if MaxMind thinks a range belongs to anonymous proxies, they don't put
anything there. Hence, we omit those ranges and resolve them all to '??'.
That's not what we want.
What we should do is first try country->iso_code, and if there's no such
key, try registered_country->iso_code which is the country in which the
ISP has registered the IP address.
In short: let's fill all A1 entries with what ARIN et. al think.
"""
clang 3.4 introduced a new by-default warning about unused static
functions, which we triggered heavily for the hashtable and map function
generating macros. We can use __attribute__ ((unused)) (thanks nickm for
the suggestion :-) ) to silence these warnings.
Apparently fedora currently has ECDH but not P224. This isn't a huge
deal, since we no longer use OpenSSL's P224 ever (see #9780 and
72c1e5acfe). But we shouldn't have segfaulting benchmarks really.
Fixes bug 10835; bugfix on 0.2.4.8-alpha.
Right now this accounts for about 1% of circuits over all, but if you
pick a guard that's running 0.2.3, it will be about 6% of the circuits
running through that guard.
Making sure that every circuit has at least one ntor link means that
we're getting plausibly good forward secrecy on every circuit.
This implements ticket 9777,
