Hi Dick, On 5/9/21 2:01 PM, Dick Franks wrote: > Pre-processing of '\\,' into the RFC1035 standard '\,' is > superficially attractive, but also fraught with danger. > > A parser could have some fun with this one: > > $ORIGIN example.com > @ SVCB 1 foo > key6="\032\001\013\184\000\000\000\000\000\000\000\000\\\\,\000" > ; a.k.a. ipv6hint=2001:db8::5c5c:2c00
A zone owner/editor would never even think of typing in IP addresses like that. And no decoder should ever write that out (and if it does, would a zone-owner read it?). Also, when using the generic format, the full value should be the 'wire' format so there's comma delimiter between values. For ALPN you'd have [value1 len][value 1][value2 len][value2] and for key6 [encoded first ipv6 address bytes][encoded second ipv6 address bytes]. > The spec only needs to say that a comma needs to be escaped ( \, ) in > order to be disregarded as a separator. > BIND, NSD, Net::DNS, and PowerDNS can all do this, so there is little > mileage in claiming that it is not possible. > > The "impossible" can be made possible by doing the right things in the > correct order. > Selecting the right things and the correct order is left as an > exercise for the student. >From what I gather, this is the case? With the caveat that there is a 2-step process for parsing the values for keys defined as paramlists. Cheers, Pieter _______________________________________________ DNSOP mailing list DNSOP@ietf.org https://www.ietf.org/mailman/listinfo/dnsop
