On 08/19/12 11:35, Curtis Villamizar wrote:
I'm trying to run isc-dhcpd using dhcpd -6 in a jail. No luck.The following code is run in the jail and doesn't fail. if (inet_pton(AF_INET6, All_DHCP_Relay_Agents_and_Servers, &mreq.ipv6mr_multiaddr)<= 0) { log_fatal("inet_pton: unable to convert '%s'", All_DHCP_Relay_Agents_and_Servers); } mreq.ipv6mr_interface = if_nametoindex(info->name); if (setsockopt(sock, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq, sizeof(mreq))< 0) { log_fatal("setsockopt: IPV6_JOIN_GROUP: %m"); } where All_DHCP_Relay_Agents_and_Servers is defined as "FF02::1:2". Later dhcpd binds to *.517 which can be seen in netstat -an. Packets to ff02::1:2.517 are seen on the jailer (as opposed to the jailee) using tcpdump, but no packets are received by the jailee. When the same command from the jailer using a chroot to the jailee directory, the multicast packets are received. Is there a solution to this other than changing the jail from an implied "ip6=new" with a specific address to "ip6=inherit". What I'd really like is a yet to be invented "ip6=new+multicast". Using "ip6=inherit" would be OK, adding very little exposure (mostly DoS attack exposure). It would be nice if "ip6=inherit" were supported in the rc.d/jail framework. Before I go changing anything I'm asking whether allowing the multicast join and then not passing multicast to the jail is considered a bug and how it should behave (the join should have failed or the packets should have arrived). If the best workaround for now is "ip6=inherit" would adding jail_<jailname>_ip[46] variables to the rc files be viewed as a good solution (with a comment in /etc/defaults/rc.conf indicating that the interaction between setting addressing using _ip and _ip_multi and setting _ip4 or _ip6 (setting an address for each family forces "ip[46]=net" for that AF. Curtis
Offhand, it does sound like a bug. I imagine the solution would be to reject the join - at least the easy solution to be done first until something more complicated can be done to make jails play nice with multicast. - Jamie _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-jail To unsubscribe, send any mail to "[email protected]"
