[IPsec] Stephen Farrell's Yes on draft-ietf-ipsecme-ikev2-null-auth-06: (with COMMENT)

["Stephen Farrell" <[e-mail]>]

Stephen Farrell has entered the following ballot position for
draft-ietf-ipsecme-ikev2-null-auth-06: Yes

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COMMENT:
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- 2.1: just wanted to check as I didn't have time to go
through it all myself - are we confident that using
SK_pi/SK_pr in this way has no cryptographic downsides? The
reference to the EAP methods convinces me this is no worse
than an existing thing, but not (by itself) that it is
cryptographically sound, so I just wanted to check as I
think prf(SK_pr,IDr') has until now been calculated but not
transmitted, so there's a tiny change here maybe, but as I
said I didn't have time to fully check. If someone just
tells me that yes, the authors/wg did consider this, that'll
be fine, no need to fully explain to me why using SK_pr like
this is safe (though if you want to, that'd be fine too).

- 2.5: "hand out" is an odd phrase here - would be better
to expand on that I think and say more precisely what
should never be done.