From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from [10.3.1.93] (helo=sc8-sf-list1-new.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1FlUkj-0000MN-RO for user-mode-linux-devel@lists.sourceforge.net; Wed, 31 May 2006 10:45:05 -0700 Received: from sc8-sf-mx2-b.sourceforge.net ([10.3.1.92] helo=mail.sourceforge.net) by sc8-sf-list1-new.sourceforge.net with esmtp (Exim 4.43) id 1FlUkj-0002Qj-Tz for user-mode-linux-devel@lists.sourceforge.net; Wed, 31 May 2006 10:45:05 -0700 Received: from smtp003.mail.ukl.yahoo.com ([217.12.11.34]) by mail.sourceforge.net with smtp (Exim 4.44) id 1FlUkf-00019m-IO for user-mode-linux-devel@lists.sourceforge.net; Wed, 31 May 2006 10:45:05 -0700 From: Blaisorblade Subject: Re: [uml-devel] Re: Randomize on MAC address when bringing up ethernet iface References: <200605302013.00091.blaisorblade@yahoo.it> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200605311924.03674.blaisorblade@yahoo.it> Sender: user-mode-linux-devel-admin@lists.sourceforge.net Errors-To: user-mode-linux-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: The user-mode Linux development list List-Post: List-Help: List-Subscribe: , List-Archive: Date: Wed, 31 May 2006 19:24:03 +0200 To: user-mode-linux-devel@lists.sourceforge.net Cc: Jason Lunz On Wednesday 31 May 2006 19:09, Jason Lunz wrote: > blaisorblade@yahoo.it said: > > I've being thinking to this and I'm wondering why we shouldn't do it. > > When we have set no IP or 0.0.0.0, which is not a unique IP, and we bring > > it up, we should choose a random MAC to use. > I agree this makes sense. Currently I'm forced to do it in a script. > > It's especially silly that uml virtual ethernet devices *don't* get > random mac addresses automatically, while tuntap virtual ethernet > devices *do* (in the same kernel tree!). > > Conditions: the broadcast bit must be 0 and the "locally-assigned address > > flag" must be 1 (as likely we already do). > > random_ether_addr() in include/linux/etherdevice.h already takes care of > this. Correct, it would have been a pity if this didn't exist. Thanks a lot! But because of the bit order problem, when I saw on some messages randomly assigned MACs (either for TAP or for some other interfaces) I wrongly thought they were global MACs (I expected to see 0x80 as highest-order bit, for multicast/broadcast, and 0x40 as "local" flag). -- Inform me of my mistakes, so I can keep imitating Homer Simpson's "Doh!". Paolo Giarrusso, aka Blaisorblade (Skype ID "PaoloGiarrusso", ICQ 215621894) http://www.user-mode-linux.org/~blaisorblade Chiacchiera con i tuoi amici in tempo reale! http://it.yahoo.com/mail_it/foot/*http://it.messenger.yahoo.com ------------------------------------------------------- All the advantages of Linux Managed Hosting--Without the Cost and Risk! Fully trained technicians. The highest number of Red Hat certifications in the hosting industry. Fanatical Support. Click to learn more http://sel.as-us.falkag.net/sel?cmd=lnk&kid=107521&bid=248729&dat=121642 _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel