Multicast packets sent from local applications that use the IF_MULTICAST_LOOP are to be sent to the specified interface as well as being delivered to all local applications on the host listening for the right multicast address. But i found that the looped packets for local applications are being filtered in PREROUTING. I want to accept them to not break local applications that depends on it, but there isn't an easy way to accept them. but in PREROUTING i also have a NFQUEUE target for incoming multicast packets to do MAC-based accounting/filtering/marking, and these looped packets are delivered with bogus source MAC addresses. I found out that this bogus MAC address is taken from the IP header. For example, the given looped packet : 45 00 00 3d 00 00 40 00 ff 11 ce 05 0a 00 01 02 e0 00 00 fb .... yield this sMAC : 40:00:ff:11:ce:05, as if the IP header was treated as a MAC header. The LOG target display these packets as having no MAC address (Indeed, the multicast loop code strips the MAC header). By looking at the code, nf_queue.c and ipk_LOG.c access the mac address in different ways, and i don't know which one should be used and what should be fixed. -- To unsubscribe from this list: send the line "unsubscribe netfilter" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
