Ippp does not support filtering in the recent gentoo-kernel-sources and isdn4k-utils. There are patches available (e.g.http://trash.net/~kaber/ippp-filter/ ) but I have not tested them. Additionally it would be nice to configure ppp and ippp to automatically filter P2P packets so a dial on demand connections would not remain alive due to these. See http://sdb.suse.de/en/sdb/html/fhassel_ppp_filtering.html for the needed filtering options according to the german computer magazine c't (they usually really know what they are doing). Reproducible: Always Steps to Reproduce: 1. 2. 3.
The ppp package does include support for the filtering with the use active-filter flag, however as there are quite a few options to the filtering, I cannot champion auto-filtering any packets. Only the box owner can decide realisticly which packets to filter. Also this bug should probably note although supposedly 2.4.x kernels support the filtering option, Ive only noticed it on my 2.5 series.
*** Bug 20744 has been marked as a duplicate of this bug. ***
According to the suse link- A solution is available for services using pppd (modem, ADSL), but not for ISDN connections where ipppd is used. As I have previously stated ppp is is already patched for filtering ppp, but as don't have ippp and trash.net is not coming up, I have no way of verifying that ippp filtering works in any way whatsoever. As for the kernel patch for filtering, that is a little beyond my area of knowledge, AFAIK none of the 2.4 series include this patch in gentoo, which is why it's cc the x86 team, the 2.5 series is the only stock support kernel-wise. If any of the other devs using ippp would like to take a crack at it and test it and pop me a patch, I will be more than happy to include it:) For now, theres little more I can do with it.
Resolving after reading this in the changelog: Changes: -------- 2003-10-21: - Probably should have been mentioned here earlier, the patch has been included in linux 2.4.22. It apparently still needs porting to 2.6 but that's another issue.
