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.
When we have more than two return values, we should really be using
an enum rather than "-2 means this, -1 means that, 0 means this, and
1 or more means a number."
The latest GeoLite2 database includes a pointer from 2001::/32 to the root
node of the IPv4 address space in the tree. We need to exclude this whole
address space from geoip6, similar to how we exclude IPv4-mapped IPv6
addresses and the 6to4 mapping subnet.
It's increasingly apparent that we want to make sure we initialize our
PRNG nice and early, or else OpenSSL will do it for us. (OpenSSL
doesn't do _too_ bad a job, but it's nice to do it ourselves.)
We'll also need this for making sure we initialize the siphash key
before we do any hashes.
I've made an exception for cases where I'm sure that users can't
influence the inputs. This is likely to cause a slowdown somewhere,
but it's safer to siphash everything and *then* look for cases to
optimize.
This patch doesn't actually get us any _benefit_ from siphash yet,
since we don't really randomize the key at any point.
siphash is a hash function designed for producing hard-to-predict
64-bit outputs from short inputs and a 128-bit key. It's chosen for
security and speed.
See https://131002.net/siphash/ for more information on siphash.
Source: https://github.com/majek/csiphash/
This is a bugfix on 0.2.2.26-beta, because 6b83b3b made directory
authorities remove themselves from the list of directory authorities to
upload to, but didn't suppress the warning in case they're the only
directory authority in the network.
(There is no longer meaningfully any such thing as a HS authority,
since we stopped uploading or downloading v0 hs descriptors in
0.2.2.1-alpha.)
Implements #10881, and part of #10841.
