On Sun, Apr 12, 2015 at 6:35 AM, Lennart Poettering <lenn...@poettering.net> wrote: > On Fri, 10.04.15 13:03, Nick Owens (misch...@offblast.org) wrote: > >> From: mischief <misch...@offblast.org> >> >> The maximum domain name size is larger than the maximum host name size. >> The smaller limit causes valid domains provided by DHCP or .network >> files to be silently ignored. > > Hmm? > > Can you give an example?
if you set the Domains key in the [Network] section of a systemd.network file to a domain longer than a label, then it will be ignored. the same is true if your DHCP server sends a domain in option 15 (domain name) that is longer than a label. it will be ignored too. both of these code paths call 'hostname_is_valid', which will fail if passed something larger than a label, which a domain name can be. > > What is a domain name according to your definition? And what a > hostname? rfc 1035 2.3.4. Size limits describes labels as being 63 octets or less and domain names as 255 octets or less. > > So far, a hostname in my definition was either a single label, or an > fqdn, and a domain name the part of the fqdn with the first label > removed... > > With such a definition I am not sure I understand the patch, hence > please explain, and give a valid example of where this turns out to be > an issue? an easy way to reproduce (for me) is to have networkd do dhcp, and have my dhcp server (dnsmasq) send some domain that is very long (longer than a label) in option 15. try "supercalifragilisticexpialidocioussupercalifragilisticexpialidocious", or the output of `uuidgen`.`uuidgen` as your domain, and networkd will ignore it because hostname_is_valid won't accept it due to the length. > > Lennart > > -- > Lennart Poettering, Red Hat _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel