Notifier chains bug ?

Oleg Kutkov

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Mar 1, 2010, 7:10:02 PM3/1/10

to

Hello.
I try to used notifier chains for monitoring network devices events.
All works perfectly when just i'm connecting/disconnecting network cable
or up/down interface via ifconfig.
But when i try to change interface address - nothing happens. Notifier
is don't send any events :(
There is many events in notifier.h:

#define NETDEV_UP 0x0001
#define NETDEV_DOWN 0x0002
#define NETDEV_REBOOT 0x0003
#define NETDEV_CHANGE 0x0004
#define NETDEV_REGISTER 0x0005
#define NETDEV_UNREGISTER 0x0006
#define NETDEV_CHANGEMTU 0x0007
#define NETDEV_CHANGEADDR 0x0008
#define NETDEV_GOING_DOWN 0x0009
#define NETDEV_CHANGENAME 0x000A
#define NETDEV_FEAT_CHANGE 0x000B
#define NETDEV_BONDING_FAILOVER 0x000C
#define NETDEV_PRE_UP 0x000D
#define NETDEV_BONDING_OLDTYPE 0x000E
#define NETDEV_BONDING_NEWTYPE 0x000F

So i receive only NETDEV_UP and NETDEV_DOWN events.

Part of my code:

//event handler
static int ifEventListener(struct notifier_block *nb, unsigned long
event, void *ptr);

//set handler
struct notifier_block nbListener =
{
.notifier_call = ifEventListener
};

//event handler
static int ifEventListener(struct notifier_block *this, unsigned long
event, void *ptr)
{
struct net_device *dev = (struct net_device *) ptr;

printk(KERN_INFO "eventListener() -- %d event from net_device '%s'
(0x%08X)\n", event, dev->name, (unsigned) dev);

return 0;
}

//register handler
register_netdevice_notifier(&nbListener);

So, this is a bug in notifier or something wrong with my code ?
Thank for any help

--
Best regards,
Oleg

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Américo Wang

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Mar 1, 2010, 10:30:01 PM3/1/10

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On Tue, Mar 2, 2010 at 8:08 AM, Oleg Kutkov <elen...@gmail.com> wrote:
> Hello.
> I try to used notifier chains for monitoring network devices events.
> All works perfectly when just i'm connecting/disconnecting network cable or
> up/down interface via ifconfig.
> But when i try to change interface address - nothing happens. Notifier is
> don't send any events :(

I think you mean IP address? No, NETDEV_CHANGEADDR is for hardware
address, not for IP address.

If you were changing mac address, you will receive NETDEV_CHANGEADDR.

Oleg Kutkov

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Mar 2, 2010, 1:00:02 AM3/2/10

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2010/3/2 Am�rico Wang <xiyou.w...@gmail.com>:

> On Tue, Mar 2, 2010 at 8:08 AM, Oleg Kutkov <elen...@gmail.com> wrote:
>> Hello.
>> I try to used notifier chains for monitoring network devices events.
>> All works perfectly when just i'm connecting/disconnecting network cable or
>> up/down interface via ifconfig.
>> But when i try to change interface address - nothing happens. Notifier is
>> don't send any events :(
>
> I think you mean IP address? No, NETDEV_CHANGEADDR is for hardware
> address, not for IP address.
>
> If you were changing mac address, you will receive NETDEV_CHANGEADDR.
>

Thank for quick answer.
Yes, i mean IP address. And what about NETDEV_CHANGE ?
Is there possible for monitoring IP address/netmask changing ?

Thank.

--
Best regards,
Oleg

Américo Wang

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Mar 2, 2010, 10:50:02 AM3/2/10

to

On Tue, Mar 02, 2010 at 07:50:01AM +0200, Oleg Kutkov wrote:
>2010/3/2 Américo Wang <xiyou.w...@gmail.com>:

>> On Tue, Mar 2, 2010 at 8:08 AM, Oleg Kutkov <elen...@gmail.com> wrote:
>>> Hello.
>>> I try to used notifier chains for monitoring network devices events.
>>> All works perfectly when just i'm connecting/disconnecting network cable or
>>> up/down interface via ifconfig.
>>> But when i try to change interface address - nothing happens. Notifier is
>>> don't send any events :(
>>
>> I think you mean IP address? No, NETDEV_CHANGEADDR is for hardware
>> address, not for IP address.
>>
>> If you were changing mac address, you will receive NETDEV_CHANGEADDR.
>>
>
>Thank for quick answer.
>Yes, i mean IP address. And what about NETDEV_CHANGE ?

It is for rtnetlink state transition.

>Is there possible for monitoring IP address/netmask changing ?
>

AFAIK, no.

Cc'ing netdev experts...

Américo Wang

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Mar 4, 2010, 5:10:02 AM3/4/10

to

On Tue, Mar 2, 2010 at 11:55 PM, Atis Elsts <atis....@gmail.com> wrote:
> I'm no expert, but IMHO for handling IP address changes you should use
> function register_inetaddr_notifier() to register you callback and
> then wait for NETDEV_UP and NETDEV_DOWN events.
>

Oh, I think you are right.

Btw, please don't drop Cc's.

Thanks.