From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from tuna.sandelman.ca ([209.87.249.19]:35336 "EHLO tuna.sandelman.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753452AbcGSNTt (ORCPT ); Tue, 19 Jul 2016 09:19:49 -0400 From: Michael Richardson Subject: Re: [RFC bluetooth-next 01/20] 6lowpan: ndisc: don't remove short address In-Reply-To: <20160711195044.25343-2-aar@pengutronix.de> References: <20160711195044.25343-1-aar@pengutronix.de> <20160711195044.25343-2-aar@pengutronix.de> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha1; protocol="application/pgp-signature" Date: Tue, 19 Jul 2016 09:19:47 -0400 Message-ID: <1996.1468934387@obiwan.sandelman.ca> Sender: linux-wpan-owner@vger.kernel.org List-ID: To: Alexander Aring Cc: linux-wpan@vger.kernel.org --=-=-= Content-Type: text/plain {cutting many from the CC} I realized while reading your patches that I don't think we have a way for an application to tell if a packet (such as an ICMPv6 packet received on a raw IP socket) arrives with a 2-byte or 8-byte address, or for an application to ask for 8-byte address, despite there being a 2-byte address available. Do you think we could do this via neighbour caches for directly connected nodes? For not directly connected nodes part of an RPL mesh, the RPL daemon would install routes using the router's 2-byte address if it can anyway. This will matter for handling of ND, in particular the DAR/DAC processing. I also wonder: if we configure an IPv6 address via SLAAC with our 8-byte EUI64, and we configure another v6 address via SLAAC with our 2-byte address, if we should: a) always use the 2-byte layer-2 when there is a matching 2-byte v6 address in the source. and vv for 8-byte EUI64s b) preference the 2-byte layer-3 address so that it is chosen by source address selection. I think that the above probably gets us all the mechanisms we need for transmit. For receive, I think that we have no APIs that will give you the layer-2 address for an incoming packet the way that IPV6_RECVPKTINFO will do for layer-3 addresses and extensions. It would be nice to have such an API. What do others think? -- ] Never tell me the odds! | ipv6 mesh networks [ ] Michael Richardson, Sandelman Software Works | network architect [ ] mcr@sandelman.ca http://www.sandelman.ca/ | ruby on rails [ --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEVAwUBV44o8ICLcPvd0N1lAQLrUQf+KVaEf2Ml7FR3bcrrEbprcms3S573U/4q BOc6njg9n6Qu9fno8X9LDfi5iljK8JBVz9vsPDdopWOIo11Fb7N+/vkSlGaZK6jb QCJ/7Y/o40PbC2Rg4FQJLx/75zo2oJgUjjd57OAm7AM3f9mhd1HhHS4dc88Qhm2j ESPFZiuZko1Bd/4lUImjx+zYCWof2be8Fzm6/Fw0ybbofTHXiRrabR/dRVCewF2D DMbPv6oJzwUFQ0RMbl4b0wKKbWup8gYcQsmT7YOdC9wsn5Q4/qkcYFStOcg9IcWI khXIMj1hBSCTwMIm5CswOpDgKCrWg/BEATXm/scAktOZMQx6IYjuRw== =vyBq -----END PGP SIGNATURE----- --=-=-=--