> On 4/9/19 9:59 AM, Ian Lepore wrote: > > On Tue, 2019-04-09 at 09:33 -0700, John Baldwin wrote: > >> On 4/9/19 9:17 AM, Ian Lepore wrote: > >>> On Tue, 2019-04-09 at 09:11 -0700, John Baldwin wrote: > >>>> On 4/9/19 6:54 AM, Ganbold Tsagaankhuu wrote: > >>>>> Author: ganbold > >>>>> Date: Tue Apr 9 13:54:08 2019 > >>>>> New Revision: 346052 > >>>>> URL: https://svnweb.freebsd.org/changeset/base/346052 > >>>>> > >>>>> Log: > >>>>> In some cases like NanoPI R1, its second USB ethernet > >>>>> RTL8152 (chip version URE_CHIP_VER_4C10) doesn't > >>>>> have hardwired MAC address, in other words, it is all zeros. > >>>>> This commit fixes it by setting random MAC address > >>>>> when MAC address is all zeros. > >>>>> > >>>>> Reviewed by: kevlo > >>>>> Differential Revision: > >>>>> https://reviews.freebsd.org/D19856 > >>>> > >>>> It would be best to not use a purely random mac address and to > >>>> use > >>>> the > >>>> function kevans@ added recently. That function generates a MAC > >>>> address > >>>> from the FreeBSD OUI using a cryptographic hash so you get a > >>>> stable address across boots on a given host. > >>>> > >>> > >>> How could that possibly work? If it's not random, you can't have > >>> two > >>> such devices on the same network. If it is random, it's not stable > >>> from one boot to the next. > >> > >> It uses the UUID and interface name as input into the hash. > > > >> The UUID is per-host. > > > > Oh, so it only works on x86 (or I guess any system that has something > > like a bios that can provide you with a uuid that doesn't change from > > one boot to the next). > > The function is in one centralized place where you are free to add other > data as input into the hash. We do always generate a uuid that we save > on boot if we aren't seeded with one by firmware, though that is probably > too late for this driver (so +1 may in fact be a better route). It should > be fine for psuedo interfaces created post-boot though even on non-x86 due > to /etc/rc.d/hostid. Pure random MAC's are not really great either.
Cant the loader load /etc/rc.d/hostid and put it in something that the kernel could get at, or a module written that handles this? > -- > John Baldwin -- Rod Grimes rgri...@freebsd.org _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
