See the complaint on #4039. This doesn't fix that particular
issue (it's somewhat unrelated), but does solve around
a file parsing problem reported by @void-in
get() should get get_once() (intent is to get 4 bytes,
not timeout after 4 seconds), no need to escape equals
signs in regexes, no need to newline the unexpected
responses.
Also refers to port 264/TCP as the SecuRemote service instead of the
Topology service (I believe this is correct)
Reporting is initially conservative -- if we don't get something for
fw_hostname, then don't bother reporting at all; assume we're
mis-identifying the target.