Re: IFF_PROMISC again
Stephen, I think your mail didn't make it to netdev. Majordomo seems to be working badly with special charsets (my mails used to be totally ignored because of charset and/or encoding issues). On 5/27/07, Stephen Hemminger [EMAIL PROTECTED] wrote: Wow, I searched for this a lot! It could be all I need, although it doesn't seem very robust to look at the bitmap driectly, is it? Maybe it would be cleaner to add an promiscuity file to that structure? /sys/class/net/ethX/flags was an interface mistake. Don't depend on it. I added it back when sysfs was first starting. Most of the files in /sys/class/net/ethX are really meant only for debugging. There was no debugfs at the time. The problem is it exports bit values as ABI that shouldn't be nailed down. Great that you point it out. Then, we're back to the initial situation, there is no reliable way of polling promisc state, and I am looking for a way to do that. Ways I think it could be done: - Exporting /sys/class/net/ethX/promiscuity as a counter (I have a working patch for this) - Exporting /sys/class/net/ethX/promisc as a binary value, from dev-flags. - ORing the two IFF_PROMISC flags in dev_get_flags() (the patch I sent) - Dropping gflags altogether, as there doesn't seem to be any real use case for it, and keep using dev_get_flags(). Any suggestion? -- Martín Ferrari - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: IFF_PROMISC again
Hi Ben, On 5/22/07, Ben Greear [EMAIL PROTECTED] wrote: PACKET_(ADD|REMOVE)_MEMBERSHIP, I need to query the real device state. I have the same problem. I think you can tell by looking at bit 0x100 in /sys/class/net/[ethX]/flags Not exactly fun to use, but it seems to work. Wow, I searched for this a lot! It could be all I need, although it doesn't seem very robust to look at the bitmap driectly, is it? Maybe it would be cleaner to add an promiscuity file to that structure? -- Martín Ferrari - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: IFF_PROMISC again
Hi David, On 5/22/07, David Miller [EMAIL PROTECTED] wrote: Anyone know the reasoning for masking out the PROMISC flag in dev_get_flags() ? Because promiscuous status is a counter, not a binary on-off state. You can't expect to just clear it and expect all the other promiscuous users to just go away and be ok with the device leaving promiscuous mode. Yes, this is fully understood. Since you can't sanely set it, we don't provide it either. I think it's cleaner how is done now, but the needed information is hidden, not having a proper way of querying the counter or the real (binary) promiscuous state is a problem for userspace. Do you think the patch I suggested is not a good idea? Do you think there is a acceptable way of exporting that info to userspace? (as I just said to Ben, the /sys/.../flags file doesn't seem a very clean way of checking it). -- Martín Ferrari - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: IFF_PROMISC again
Martín Ferrari wrote: Hi, for the nth time I send this email, hoping that majordomo won't eat it again. I know this has been extensibly discussed circa 2001, but I found that there's still problems: in debian (at least) neither ifconfig nor ip can tell that the interface is in promiscuous mode. I know about the deprecation of IFF_PROMISC, but I couldn't find out which is the current way of knowing the real state of the interface. I want to fix ifconfig, so this is not an issue of PACKET_(ADD|REMOVE)_MEMBERSHIP, I need to query the real device state. I have the same problem. I think you can tell by looking at bit 0x100 in /sys/class/net/[ethX]/flags Not exactly fun to use, but it seems to work. Anyone know the reasoning for masking out the PROMISC flag in dev_get_flags() ? Ben -- Ben Greear [EMAIL PROTECTED] Candela Technologies Inc http://www.candelatech.com - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: IFF_PROMISC again
From: Ben Greear [EMAIL PROTECTED] Date: Tue, 22 May 2007 17:08:18 -0700 Anyone know the reasoning for masking out the PROMISC flag in dev_get_flags() ? Because promiscuous status is a counter, not a binary on-off state. You can't expect to just clear it and expect all the other promiscuous users to just go away and be ok with the device leaving promiscuous mode. Since you can't sanely set it, we don't provide it either. - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: IFF_PROMISC again
David Miller wrote: From: Ben Greear [EMAIL PROTECTED] Date: Tue, 22 May 2007 17:08:18 -0700 Anyone know the reasoning for masking out the PROMISC flag in dev_get_flags() ? Because promiscuous status is a counter, not a binary on-off state. You can't expect to just clear it and expect all the other promiscuous users to just go away and be ok with the device leaving promiscuous mode. Yes, I understand why you wouldn't let a user set promisc in this manner. Since you can't sanely set it, we don't provide it either. What harm is there letting the user know if their hardware is PROMISC or not, regardless of how it got that way? Also, it seems you *can* at least turn it on with ifconfig, and you can decrement at least once with ifconfig as well. If nothing else has promiscuity set, then this will indeed toggle the state, right? Thanks, Ben -- Ben Greear [EMAIL PROTECTED] Candela Technologies Inc http://www.candelatech.com - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
IFF_PROMISC again
Hi, for the nth time I send this email, hoping that majordomo won't eat it again. I know this has been extensibly discussed circa 2001, but I found that there's still problems: in debian (at least) neither ifconfig nor ip can tell that the interface is in promiscuous mode. I know about the deprecation of IFF_PROMISC, but I couldn't find out which is the current way of knowing the real state of the interface. I want to fix ifconfig, so this is not an issue of PACKET_(ADD|REMOVE)_MEMBERSHIP, I need to query the real device state. Also, it's unclear to me what happens when you set/reset IFF_PROMISC and then libpcap fiddles with membership. Is this documented somewhere? It has been said many times that ip should give this information. I cannot see this: $ sudo tcpdump -ni eth2 port $ dmesg |tail -2 device eth2 entered promiscuous mode audit(1175904782.767:40): dev=eth2 prom=256 old_prom=0 auid=4294967295 $ ip link show eth2 4: eth2: BROADCAST,MULTICAST,UP,1 mtu 1500 qdisc pfifo_fast qlen 1000 link/ether 00:18:de:81:24:a2 brd ff:ff:ff:ff:ff:ff $ ip -V ip utility, iproute2-ss060323 I think that is a problem for user tools to not know about this, and I want to fix them. I don't know how. Can anyone give me a pointer? Thanks, Martín. -- Martín Ferrari [EMAIL PROTECTED] - To unsubscribe from this list: send the line unsubscribe netdev in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
