On Wed, Jul 22, 2020 at 01:46:38PM +0200, Ladislav Lhotka wrote: > > > On 22. 07. 20 13:00, Juergen Schoenwaelder wrote: > > Tom, > > > > my understanding is that Lada is now proposing something slightly > > different but I am not sure what exactly, hence I asked again. > > Oh yes, I messed it up by mixing different things together, sorry. I > checked again the ML archive, and the message that is relevant to this > thread is this: > > https://mailarchive.ietf.org/arch/msg/netmod/PISOifrtow4oWLGW7meBBSri7nM/ > > The aim of that proposal was to limit the "inet:host" type to DNS names > that are reasonable as host names, i.e. eliminate values like "." or "_".
You are proposing to change the length restriction from 1..253 to 2..253 following RFC 952: [...] Single character names or nicknames are not allowed. And you add pattern '(.*\.)?..\-\-.*' { modifier invert-match; } to restrict things to non-reserved letter-digit-hyphen labels as per RFC 5890. Is it clear that this second restriction applies to host names? How do you represent internationalized host names? Perhaps we need a collection of examples? And is the pattern correct? RFC 5890 says: Reserved LDH labels, known as "tagged domain names" in some other contexts, have the property that they contain "--" in the third and fourth characters but which otherwise conform to LDH label rules. What is the '(.*\.)?' part doing in your pattern? Finally, would it be useful to derive a host-name type from the domain-name type (if host-names are really a strict subset of what domain-name allows), e.g.: typedef host-name { type domain-name { pattern '(.*\.)?..\-\-.*' { modifier invert-match; } length "2..max"; } description "Host names must be at least two characters long (see RFC 952) and they are restricted to non-reserved letter-digit-hyphen (NR-LDH) labels (see RFC ????)."; reference "RFC 952: DoD Internet Host Table Specification RFC ????: ????"; } /js -- Juergen Schoenwaelder Jacobs University Bremen gGmbH Phone: +49 421 200 3587 Campus Ring 1 | 28759 Bremen | Germany Fax: +49 421 200 3103 <https://www.jacobs-university.de/> _______________________________________________ netmod mailing list netmod@ietf.org https://www.ietf.org/mailman/listinfo/netmod