Balazs Scheidler wrote: > The use-case is as follows: > > * I have two different subsystems creating interfaces dynamically (for > example pptpd and serial pppd lines, each creating dynamic pppX > interfaces), > * I would like to assign a different set of iptables rules for these > clients, > * I would like to react to a new interface being added to a specific set > in a userspace application, > > The reasons I see this needs new kernel functionality: > > * iptables supports wildcard interface matching (for example "iptables > -i ppp+"), but as the names of the interfaces used by PPTPD and PPPD > cannot be distinguished this way, this is not enough, > * Reloading the iptables ruleset everytime a new interface comes up is > not really feasible, as it abrupts packet processing, and validating the > ruleset in the kernel can take significant amount of time, > * the kernel change is very simple, adapting userspace to this change is > also very simple, and in userspace various software packages can easily > interoperate with each-other once this is merged. > > The implementation: > > Each interface can belong to a single "group" at a time, an interface > comes up without being a member in any of the groups. > > Userspace can assign interfaces to groups after being created, this > would typically be performed in /etc/ppp/ip-up.d (and similar) scripts. > > In spirit "interface group" is somewhat similar to the "routing > protocol" field for routing entries, which contains information on which > routing daemon was responsible for adding the given route entry. > > Things to be done if you like this approach: > > * interface group match in iptables, > * support for naming interface groups in userspace, a'la routing > protocols, > * emitting a netlink notification when the group of an interface > changes, > * possibly converting the "ip link" command to use NETLINK messages, > instead of using ioctl() > > What do you think?
I like it .. kind of like routing realms. For your specific case there is a possible solution already supported by the kernel, you can pre-allocate ppp devices using PPPIOCNEWUNIT, rename them and later attach to individual units in the ppp daemon using PPPIOCATTACH (I have a patch for this somewhere if you're interested). But that only works for PPP devices and the group idea looks more flexible. - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
