howto setup a route by netlink socket

howto setup a route by netlink socket

[C.J]

Hi list,

I want to set a route by netlink socket but I've no idea how to do it clearly.

Here I've make up a virtual interface that is ppp0 by ioctl, we want to it could communicate with peer side.
We need just a route, right?  Netlink can do this. As there are many attributes , we need tell kernel what's our route.
But I'm not sure what we should build as attributes that we will send to kernel.

Now I get a simple talk, it contains 2 attrs follow 'rtmsg' structure. 
 RTA_DST, 192.168.1.1 -- the peer IP
 RTA_SRC, 192.168.1.2 -- our local IP
And it cannot work, kernel return [No such Device] error.
I think there are something I lost, pls help me and point out the errors.

Reg


--
c.j
  

Re: howto setup a route by netlink socket

[James Cameron]

You could look at the ip(8) command source to find out how it is done,
/sbin/ip or /bin/ip is part of the iproute package on Red Hat and Debian
based Linux distributions.

Latest version of pptp has a hack that uses system(3) to execute ip(8).
If you can figure a way to do this without using system(3) then I'm
quite interested.

-- 
James Cameron                         http://quozl.netrek.org/
HP Open Source, Volunteer             http://opensource.hp.com/
PPTP Client Project, Release Engineer http://pptpclient.sourceforge.net/

Re: howto setup a route by netlink socket

[James Chapman]

James Cameron wrote:
> You could look at the ip(8) command source to find out how it is done,
> /sbin/ip or /bin/ip is part of the iproute package on Red Hat and Debian
> based Linux distributions.

The ip command uses libnetlink, but there's a new netlink library that 
is much easier to use. It's called libnl, at 
http://people.suug.ch/~tgr/libnl/. It includes simple apps that do 
common things like add routes. Binary packages are available for modern 
distros.

> Latest version of pptp has a hack that uses system(3) to execute ip(8).
> If you can figure a way to do this without using system(3) then I'm
> quite interested.


-- 
James Chapman
Katalix Systems Ltd
http://www.katalix.com
Catalysts for your Embedded Linux software development

Re: Re: howto setup a route by netlink socket

[C.J]

Hi James Chapman

>>
>James Cameron wrote:
>> You could look at the ip(8) command source to find out how it is done,
>> /sbin/ip or /bin/ip is part of the iproute package on Red Hat and Debian
>> based Linux distributions.

>The ip command uses libnetlink, but there's a new netlink library that 
>is much easier to use. It's called libnl, at 
>http://people.suug.ch/~tgr/libnl/. It includes simple apps that do 
>common things like add routes. Binary packages are available for modern 
>distros.

>> Latest version of pptp has a hack that uses system(3) to execute ip(8).
>> If you can figure a way to do this without using system(3) then I'm
>> quite interested.

Thanks a lot, I'll try.

Reg

--
c.j