From mboxrd@z Thu Jan  1 00:00:00 1970
From: YOSHIFUJI Hideaki <hideaki.yoshifuji@miraclelinux.com>
Subject: Re: [RFC] ipv6: use a random ifid for headerless devices
Date: Tue, 1 Dec 2015 16:39:11 +0900
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Hi,

Bj=C3=B8rn Mork wrote:
> =E5=90=89=E8=97=A4=E8=8B=B1=E6=98=8E <hideaki.yoshifuji@miraclelinux.=
com> writes:
>=20
>>>> +static int addrconf_ifid_random(u8 *eui, struct net_device *dev)
>>> +{
>>> +       get_random_bytes(eui, 8);
>>> +       eui[0] |=3D 0x02;
>>> +       return 0;
>>> +}
>>> +
>>
>> Since random identifier is locally assigned, drop the global bit
>> instead if setting it.
>=20
> Yes, definitely. Thanks.  I'm considering reusing __ipv6_regen_rndid(=
)
> which already does this correctly, and also avoids some locally assig=
ned
> addresses with special meanings.
>=20
> Another issue with the initial RFC is that every prefix will have a n=
ew
> random ifid, which isn't necessarily what the users expect.  I wonder=
 if
> it would be acceptable to abuse the rndid field for storing a "perman=
ent"
> random ifid?

Well, I think we should introduce ifid in inet6_dev.
After that we could use it from other ifid methods.

--yoshfuji

>=20
>=20
> Bj=C3=B8rn
>=20

--=20
Hideaki Yoshifuji <hideaki.yoshifuji@miraclelinux.com>
Technical Division, MIRACLE LINUX CORPORATION