add a parameter to resolver api that is the vrf identifier. this permits
to make resolution self to each vrf. in case vrf netns backend is used,
this is very practical, since resolution can happen on one netns, while
it is not the case in an other one.
Signed-off-by: Philippe Guibert <philippe.guibert@6wind.com>
To keep the calling code agnostic of the DNS resolver libary used, pass
a strerror-style string instead of a status code that would need extra
handling.
Signed-off-by: David Lamparter <equinox@diac24.net>
libc-ares doesn't do IP literals, so we have to do that before running
off to do DNS. Since this isn't BMP specific, move to lib/ so NHRP can
benefit too.
Signed-off-by: David Lamparter <equinox@diac24.net>
