Differential D55031
netinet6: Pass IPv4-mapped ASM multicast joins/leaves to netinet. Authored by bms on Feb 1 2026, 4:56 AM. Tags None Referenced Files
Details Add comment about future IPv4 source-address selection support. This has been compile tested with LINT and LINT-NOINET, EAFNOSUPPORT change moved to D55233. Inspired by: xnu (Clean-roomed from APSL change) Kyua tests will follow in a separate commit. I note that not all of the legacy IP multicast regression tests were ported to ATF over the years.
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Event TimelineComment Actions The IPv4 mapped behaviour is limited to ASM memberships only, and is not directly mandated by an RFC. The comments around in6u_lookup_v4mapped_mc() reflect this-- it's something that has seen wider use than one would anticipate, despite it being kind of dog stupid to do IPv4 operations on an IPv6 socket. This revision is also missing a man page update. Historically Pavlin Radoslavov has handled the multicast routing end of things, here it needs to go in ip6(4). @bz: The Apple xnu code has cleaned up scope ID handling, so that may be They renamed in6_joingroup_locked() to in6_mc_join() which is a little confusing, and it looks like they demoted the per-socket SSM filters from an RB-tree to a growable array. That I can understand; stuff gets merged into the stack-wide RB-tree for each group anyway. However I didn't check what changes they may have made to imo_multi_filter(), yet. OT: Apple do not provide meaningful change history in their xnu drops on GitHub, which is extremely inconvenient. OT: I am in touch separately with core-secretary@ to open a dialogue about regaining full commit access after a 7.5 year hiatus for health & bereavement reasons. Comment Actions Bruce, very glad to see you back!!!
Comment Actions Please check that this compiles properly with possible combinations INET, INET6, INET & INET6. It looks to be as if your using INET to protect INET6 only code. Um, probably wrong on that, as these files well not be pulled in unless compiling INET6 Comment Actions The #ifdef INET is not being used in its normal sense; it is there to denote that the IPv4-mapped address support requires INET, despite being referenced from a file that is covered by the INET6 option. So your initial confusion is understandable. Also, the only reason this trick works at all is that inpcb->inp_moptions exists and is populated even for PF_INET6 sockets. Comment Actions Do you plan to rebase that over removal of IFP_TO_IA() in preference to in_ifprimaryaddr()? | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||