Since linux kernel >= 2.6.33 the kernel option "accept_local" can be modified:
Accept packets with local source addresses. In combination with suitable routing, this can be used to direct packets between two local interfaces over the wire and have them accepted properly.
Is there any IPv6 equivalent to this option? If not, is there a patch or plans to implement it in the near future?
Edit: I am using two WIFI Interfaces and have created propper routing rules, which allow me to send packets between these local interfaces over WIFI (no loop-device). I could add routing rules for IPv6 but without this option packets will be dropped as "martian packets". Packets are only accepted, when this boolean is TRUE.