grovel netfilter_conntrack_xxx from applications how?

grovel netfilter_conntrack_xxx from applications how?

[Tyler Retzlaff]

How does one query netfilter for information about conntrack connections
when they are established, disestablished etc..?

Basically for connections established via conntrack_xxx modules I want
to extract the details and use them in an application on the router.   
Is there
documentation to a C API for doing this?

Thanks

Re: grovel netfilter_conntrack_xxx from applications how?

[Georgi Alexandrov]

Tyler Retzlaff wrote:

> How does one query netfilter for information about conntrack connections
> when they are established, disestablished etc..?
>
> Basically for connections established via conntrack_xxx modules I want
> to extract the details and use them in an application on the router.   
> Is there
> documentation to a C API for doing this?
>
> Thanks
>
>
check /proc/net/ip_conntrack
but remember that accessing it directly ... with cat for example is
known that may crash your machine.

P.S.
Though i've never experienced the above behaviour.

regards,
Georgi Alexandrov

Re: grovel netfilter_conntrack_xxx from applications how?

[Georgi Alexandrov]

Tyler Retzlaff wrote:

>
> On 25/11/2005, at 5:45 PM, Georgi Alexandrov wrote:
>
>> Tyler Retzlaff wrote:
>>
>>> How does one query netfilter for information about conntrack  
>>> connections
>>> when they are established, disestablished etc..?
>>>
>>> Basically for connections established via conntrack_xxx modules I  want
>>> to extract the details and use them in an application on the  
>>> router.   Is there
>>> documentation to a C API for doing this?
>>>
>>> Thanks
>>>
>>>
>> check /proc/net/ip_conntrack
>> but remember that accessing it directly ... with cat for example is
>> known that may crash your machine.
>
>
> eww that doesn't sound very appealing.
>
> I was kind of hoping for something more like callback registration  
> where if a
> new session was established my userspace application was notified  
> allowing
> me to query the details.
>
> I've been reading as much as possible since the original post and  
> have only
> found references to netfilter hooks which appears to be for  
> implementing things
> like ip_conntrack.  I suppose I could fork ip_conntrack and add a  
> callback
> registration interface to it but I was hoping something already existed.
>
> Thanks
>
Perhaps you may try the ULOG (userspace logging) target.
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