> -----Original Message----- > From: owner-freebsd-hack...@freebsd.org [mailto:owner-freebsd- > hack...@freebsd.org] On Behalf Of Matthew Seaman > Sent: Tuesday, January 03, 2012 10:01 AM > To: freebsd-hackers@freebsd.org > Subject: Re: [ANN] host-setup 4.0 released > > On 03/01/2012 16:52, Rick Macklem wrote: > > The basics are in RFC4291, but I think that inet_pton(3) knows how to > > deal with it. (I think "::" can be used once to specify the longest # > > of 16bit fields that are all zeros.) > > RFC 4291 has a basic description of the textual representation of IPv6 > addresses, > but it is ambiguous: there are several different ways to present the same > address > according to the RFC 4291 rules. > > inet_pton(3) follows RFC 5952 which is a superset of the 4291 rules, only > allowing > a single, unambiguous representation for each IPv6 number. > > > After inet_pton() has translated it to a binary address, then the > > macros in sys/netinet6/in6.h can be used to determine if the address is a > loopback, etc. > > While 5952 describes how to correctly present an IPv6 address, there's still > lots of > important other stuff in 4291. For instance bit 70 in an > IPv6 address flags that the address is derived from a number hardwired into > the > interface -- typically the ethernet MAC address, as is commonly done for SLAAC > (StateLess Address Autoconfiguration: RFC 4862, rtsold(8), rtadvd(8)). So an > arbitrarily invented address should have that bit set to zero. Bit 71 is > also special, > indicating manycast vs unicast, and should also be zero for the vast majority > of > uses. > See > http://www.infracaninophile.co.uk/articles/hotchpotch.html#rand-aaaa.pl > for some perl code that operates in this area. > > Also of interest: RFC 5156 which lists IPv6 address ranges dedicated to > special > purpose usages, and RFC 4193 which roughly is the IPv6 equivalent to RFC 1918, > but somewhat more complicated. You might find > https://www.sixxs.net/tools/grh/ula/ relevant too, although actually using > that > as a registry is pretty pointless. >
Thank you ALL for such great feedback. We'll have to digest this information in entirety and also start playing with rtsold and rtadvd in the lab. When we do add IPv6 support, it will be robust and solid (we don't like to do things half-arsed). It might be awhile before host-setup supports IPv6 (only because we're not using it ourselves, just yet), but it does sound like something that is rather desired. -- Devin _____________ The information contained in this message is proprietary and/or confidential. If you are not the intended recipient, please: (i) delete the message and all copies; (ii) do not disclose, distribute or use the message in any manner; and (iii) notify the sender immediately. In addition, please be aware that any message addressed to our domain is subject to archiving and review by persons other than the intended recipient. Thank you. _______________________________________________ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "freebsd-hackers-unsubscr...@freebsd.org"
