Return-path: Received: from contumacia.investici.org ([178.255.144.35]:39245 "EHLO contumacia.investici.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932209Ab2FZSz0 (ORCPT ); Tue, 26 Jun 2012 14:55:26 -0400 Date: Tue, 26 Jun 2012 20:55:34 +0200 From: Antonio Quartulli To: Johannes Berg Cc: Will Hawkins , Will Hawkins , linux-wireless@vger.kernel.org Subject: Re: Help tracing NL80211_CMD_AUTHENTICATE as event in IBSS mode Message-ID: <20120626185533.GA7932@ritirata.org> (sfid-20120626_205533_636587_B535033A) References: <24f-4fe93400-17-239c5900@2266046> <1340693584.4662.3.camel@jlt3.sipsolutions.net> <4FE9E201.1010903@opentechinstitute.org> <1340728873.4484.6.camel@jlt3.sipsolutions.net> <4FE9E6F0.2070909@opentechinstitute.org> <1340730210.4484.11.camel@jlt3.sipsolutions.net> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="SLDf9lqlvOQaIe6s" In-Reply-To: <1340730210.4484.11.camel@jlt3.sipsolutions.net> Sender: linux-wireless-owner@vger.kernel.org List-ID: --SLDf9lqlvOQaIe6s Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Jun 26, 2012 at 07:03:30PM +0200, Johannes Berg wrote: > On Tue, 2012-06-26 at 12:44 -0400, Will Hawkins wrote: >=20 > > > Huh, now I'm confused, why would it need the authenticate frames for > > > IBSS? As far as I can tell, it looks at CMD_NEW_STA, which calls > > > nl80211_new_station_event(),=20 > >=20 > > This is what I understand as well. > >=20 > > which in IBSS sends EVENT_IBSS_RSN_START to > > > the supplicant core -- that will trigger the 4-way-handshake. No? Hen= ce > > > it doesn't need to register for auth frames, it never needs them, sin= ce > > > RSN uses open auth, if any is even used in IBSS at all. > >=20 > > This is where I am still trying to figure out exactly how it works. >=20 > I believe that when the new station is added (NEW_STA event), it will > simply send out a 1/4 EAPOL frame. Since both do that, I guess it does > some kind of de-duplication? Whoever sends it first wins or something, > but I don't really know. Maybe we should take the discussion to the > hostap list at this point :-) Yeah, Johannes is right when saying that NEW_STA simply makes wpa_s trigger= a EVENT_IBSS_RSN_START that will start a 4-way handshake. Auth frames are not used at all in wpa_s for IBSS/RSN. Auth frames are only= used in the kernel to remove and then add again a station from the neighbour lis= t. In this way wpa_s will first purge that station and then will add it again tha= nks to another NEW_STA event. @johannes: de-duplication? IBSS/RSN assumes that each node runs an authenti= cator and a supplicant. Does this mean that we need exactly two 4-way handshakes?= Why should we have a "winner"? Cheers, --=20 Antonio Quartulli =2E.each of us alone is worth nothing.. Ernesto "Che" Guevara --SLDf9lqlvOQaIe6s Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (GNU/Linux) iEYEARECAAYFAk/qBaUACgkQpGgxIkP9cwcsZgCaA3+OOEn3EjKyl8wO7wAB9nrD zV0AnAk1b2E3iIG//sW7FtNzfYXA4vPs =jC+S -----END PGP SIGNATURE----- --SLDf9lqlvOQaIe6s--