Bug 71247

Description of Problem:

As distributed, the Red Hat 7.3 ppp daemon does not support ppp filtering, which
makes setting up a dial-on demand gateway somewhat problematical.  If you don't
have active/pass filtering, ntp and dns will tend to keep the link up with their
constant babbling.  I downloaded the rawhide version 2.4.1-7 of ppp, and it
still does not have filtering enabled.  I built a ppp by hand, modifying the
Makefile to add FILTER=y, and installed the binary on my system, and it works.

Once ppp supports active filtering, a related problem is neat and the scripts in
/etc/sysconfig/network-scripts/ifcfg-ppp* don't have a good way of dealing with
the spaces that the active/pass filtering rules need.  I got around this by
editing /etc/ppp/options directly to add the filter support.

I will note that the 2.4.18-5 kernel configs have PPP_FILTER enabled.

After this it would be helpful to have examples in your setup guide for setting
up modems for common situations like dial-on demand.  Also changing the manual
page to say it now works on Linux would be helpful.

Version-Release number of selected component (if applicable):

2.4.1-3 of ppp (also rawhide ppp 2.4.1-7).

How Reproducible:

Always.

Steps to Reproduce:
1. Set up ppp on the system.
2. echo "active-filter '!(port ntp || tcp port domain || (udp dst port domain &&
 udp src port domain))'" >> /etc/ppp/options
3. ifup ppp0

Actual Results:

ppp complains that it doesn't know about active-filter.

Expected Results:

ppp supports active and pass filters.

Additional Information: