Sending ipv6 packets from a kernel module

Sending ipv6 packets from a kernel module

[Anton]

Hi all,

Please excuse me if the following question has already been asked on the 
mailing list, I am a little new to this.

I am trying to send IPv6 packets from a kernel module. As far as I 
understand, I would have to use the ip6_output() function, and this 
function is certainly present in the net/ipv6/ip6_output.c file (on my
2.6.18 kernel). Unfortunately, the function is not exported from the
IPv6 module and so my kernel module is unable to use it. Has anyone 
encountered such a problem before, and if not, does anyone know what is 
required for me to push a sk_buff into the IP stack for transmission 
(from a kernel module)?
Any ideas would be appreciated!

Regards,
Anton



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Re: Sending ipv6 packets from a kernel module

[Neil Horman]

On Mon, May 21, 2007 at 02:04:33PM +0930, Anton wrote:
> Hi all,
> 
> Please excuse me if the following question has already been asked on the 
> mailing list, I am a little new to this.
> 
> I am trying to send IPv6 packets from a kernel module. As far as I 
> understand, I would have to use the ip6_output() function, and this 
> function is certainly present in the net/ipv6/ip6_output.c file (on my
> 2.6.18 kernel). Unfortunately, the function is not exported from the
> IPv6 module and so my kernel module is unable to use it. Has anyone 
> encountered such a problem before, and if not, does anyone know what is 
> required for me to push a sk_buff into the IP stack for transmission 
> (from a kernel module)?
> Any ideas would be appreciated!
> 
> Regards,
> Anton
> 
No, you'll probably want to use something like kernel_sendmsg to send what you
want, passing in a socket created with something like sock_create_kern.

Regards
Neil

Re: Sending ipv6 packets from a kernel module

[Vlad Yasevich]

Neil Horman wrote:
> On Mon, May 21, 2007 at 02:04:33PM +0930, Anton wrote:
>> Hi all,
>>
>> Please excuse me if the following question has already been asked on the 
>> mailing list, I am a little new to this.
>>
>> I am trying to send IPv6 packets from a kernel module. As far as I 
>> understand, I would have to use the ip6_output() function, and this 
>> function is certainly present in the net/ipv6/ip6_output.c file (on my
>> 2.6.18 kernel). Unfortunately, the function is not exported from the
>> IPv6 module and so my kernel module is unable to use it. Has anyone 
>> encountered such a problem before, and if not, does anyone know what is 
>> required for me to push a sk_buff into the IP stack for transmission 
>> (from a kernel module)?
>> Any ideas would be appreciated!
>>
>> Regards,
>> Anton
>>
> No, you'll probably want to use something like kernel_sendmsg to send what you
> want, passing in a socket created with something like sock_create_kern.
> 
> Regards
> Neil
> 

You can also use ip6_xmit assuming the module has performed the necessary route lookups.

-vlad