Local process lookup is independent of the NAT engine used, it depends
only on the operating system's process enumeration API. Moving the code
out of NAT lookup also makes it work for static and SNI proxyspecs.
This exposes the pid lookup code as a standard attribute
of NAT lookup -- if a matching process cannot be found,
or if pid lookup isn't supported by the NAT backend,
a pid of -1 is returned.
This also adds the local_pid to the pxyconn context; this
will be used to populate log strings.
This uses Mac OS X's libproc to find the first process that owns
a matching socket. Currently, the results are simply logged;
the next step will be exposing this generically via
the NAT engine lookup API.
Support pf rdr on Mac OS X 10.7, 10.8 and 10.9 by including the missing
Apple headers in the source tree and enable private Apple code. Since
we are using an interface marked private by Apple, this code is very
experimental.
Issue: #15
Reported by: Amit Chowdhary
For Linux netfilter, IPV6_ORIGINAL_DST and SOL_IPV6 are defined to
SO_ORIGINAL_DST and SOL_IP respectively if they are not defined by the
system headers (they aren't defined on vanilla kernels). Undefine these
compatibility definitions after use, in order not to mess up the
diagnostic output of nat_version().
