On 29 May 2013 08:43, Antonio Quartulli <or...@autistici.org> wrote: > On Wed, May 29, 2013 at 08:36:50AM -0700, Mihail Costea wrote: >> On 26 May 2013 07:02, Antonio Quartulli <or...@autistici.org> wrote: >> > On Fri, May 17, 2013 at 03:27:51PM +0300, Mihail wrote: >> >> From: "mihail.coste...@gmail.com" <mihail.coste...@gmail.com> >> >> >> >> Added functions needed for NDP snooping, like getting the IPv6 addresses >> >> or getting the target HW address from an Neighbor Advertisement (NA). >> >> Also added functions to create NA for Neighbor >> >> Solicitations that have already the HW address in DAT. >> >> >> >> Problems: I have to generate router and override flags for NA. For now >> >> I don't now exactly how to get them. From what I've seen, batman could >> >> now which nodes are routers, but for override flag, we should find a >> >> mechanism to know if the node is proxy or has anycast address. >> >> For inspiration I have used the code at: <net/ipv6/ndisc.c>. >> > >> > What is the concept you have in mind? >> > Maybe you first explain a bit more about your idea so that we can help you >> > in >> > find a way to implement that. >> > >> > You want to edit the router address and flags carried by the NA? >> > >> >> When creating the NA response for an HW address already contained in >> the DAT, I must set 3 flags: router, solicited and override. >> >> The solicited flag is 1 because I only answer to solicited NS. >> >> The router flag should be 1 only if the device for which we have the >> HW address is a router. From what I've seen there are some functions >> in batatv for finding routers, but I'll have to see if they can be >> used on the nodes connected to mesh-nodes. Or maybe there is another >> way to see if the device is a router. > > I guess here you are looking for an IPv6 router, right? so a node which > advertised itself as it, correct? In this case in batman-adv there is nothing > which can help you because there is no IPv6 detection of any type.. > How can we recognise if a node is advertising itself as router? maybe by > snooping other NDP messages? >
I'll look into this. There are some router packets, so those might be useful. >> >> About the override flag, I don't really have an idea. I didn't >> understand very well how it was calculated in net/ipv6/ndisc.c so I >> set it to 1 by default (it should be 0 for proxy and anycast address). >> > > mh..ok. We may want to better check this once more to avoid triggering any > strange behaviour in the network :) > > Cheers, > > -- > Antonio Quartulli > > ..each of us alone is worth nothing.. > Ernesto "Che" Guevara This needs more research. Maybe we can find something for this. I'll get a laptop in 1-2 weeks, but I'll be able to work only during weekends. I'll implement the mentioned changes at that moment. -- Mihail Costea
