Ooopps, ... wrong hackers list... Sorry for the noise! Am 06.02.2014 um 12:23 schrieb Joerg Jung <m...@umaxx.net>:
> Am 05.02.2014 um 17:20 schrieb Stuart Henderson <s...@spacehopper.org>: > >> On 2014/02/05 11:10, Simon Perreault wrote: >>> Le 2014-02-05 03:33, Eric Faurot a écrit : >>>> Just a question before I commit it. The '/' character is apparently >>>> used in dname labels sometimes. Can anyone think of other chars that >>>> should be allowed too? Or do we want to be even more lenient wrt dname >>>> validation? >>> >>> Why validate at all? Strictly speaking, all bytes are allowed in DNS >>> labels... >> >> Right - the usual restriction "letters, digits or hyphens" is on host >> names only, not DNS labels. > > I do not think so. As stated in > http://tools.ietf.org/search/rfc6672#section-2.1 > > The DNAME target is a domain name as defined in > http://tools.ietf.org/search/rfc1035 Section 2.3.1 > >> https://tools.ietf.org/html/rfc6672#section-6.2 >> >> The advisory remarks in [RFC2317] concerning the choice of the "/" >> character apply here as well. > > Yes, but only for _reverse_ delegations. > >> https://tools.ietf.org/html/rfc2317 (section 4) >> >> Some DNS implementations are not kind to special characters in domain >> names, e.g. the "/" used in the above examples. As [3] makes clear, >> these are legal, though some might feel unsightly. Because these are >> not host names the restriction of [2] does not apply. Modern clients >> and servers have an option to act in the liberal and correct fashion. >> >> >> [3] https://tools.ietf.org/html/rfc2181#section-11 > > This one is obsolete and updated by others. > >> " The DNS itself places only one restriction on the particular labels >> that can be used to identify resource records. That one restriction >> relates to the length of the label and the full name. The length of >> any one label is limited to between 1 and 63 octets. A full domain >> name is limited to 255 octets (including the separators). The zero >> length full name is defined as representing the root of the DNS tree, >> and is typically written and displayed as ".". Those restrictions >> aside, any binary string whatever can be used as the label of any >> resource record. " > > >
