[pkg-dhcp-devel] Bug#563677: dhcp3-client: dhclient should not override default routing

Andrew Pollock apollock at debian.org
Mon Jul 12 00:10:57 UTC 2010


On Mon, Jan 04, 2010 at 06:51:31AM -0800, eclectic 923 wrote:
> Package: dhcp3-client
> Version: 3.1.1-6+lenny3
> Severity: important
> 
> *** Please type your report below this line ***
> 
> As I watched the various wireless security protocols get cracked,
> I decided to give up on wireless security, there's a better and
> simpler solution, openvpn. It takes a whole lot less work to set up
> openvpn-client/openvpn-server than a supplicant/radius-hostap (which I
> used to use with TKIP/AES settings). Not to mention, remote access and
> wireless access management is consolidated into one place
> (openvpn-server) vs the radius and openvpn-servers.
> 
> When my system connects to a wireless router, it runs a dhclient to set
> up the wireless interface wlan0.  Openvpn supplies my real connection thru
> the tap0 virtual network device. The firewall is set up to only allow dhcp
> traffic and openvpn traffic on the wireless link (wlan0). This also has the
> added virtue of allowing me to use any of several wireless routers, yet
> always have the same network IP address as the wired network connection,
> thereby eliminating the need for a dynamic dns server.
> 
> When using this set up, after initial connection, the default route is
> switched to the openvpn tap0 device (aka default route moves from wlan0
> to tap0).
> 
> The problem is that /sbin/dhclient-script has some 'naughty' code in it.
> 
> Specifically, under BOUND|RENEW|REBIND|REBOOT) and TIMEOUT) one finds:
> 
>         for router in $new_routers; do
>                 route add default dev $interface gw $router $metric_arg
>         done
> 
> The problem with this, is that the default route is *unconditionally*
> set. Which is why the system gets two default routes in the routing table,
> and stops working.
> 
> There needs to be a check added to make sure that the default route isn't
> already set. If the default route is set, then the naughty code should
> NOT be run. Something along the lines of:

I've been giving this some more thought.

Wouldn't your problem be just as easily addressed by not requesting the
default route (i.e. removing routers from the request directive in
dhclient.conf)?



More information about the pkg-dhcp-devel mailing list