rtnetlink: add restricted rtnl groups for ipv4 and ipv6 mroute

Add RTNLGRP_{IPV4,IPV6}_MROUTE_R as two new restricted groups for the
NETLINK_ROUTE family.
Binding to these groups specifically requires CAP_NET_ADMIN to allow
multicast of sensitive messages (e.g. mroute cache reports).

Suggested-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Julien Gomes <julien@arista.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Julien Gomes 2017-06-20 13:54:16 -07:00 committed by David S. Miller
parent 94df30a652
commit 5f729eaabe
2 changed files with 17 additions and 0 deletions

View File

@ -669,6 +669,10 @@ enum rtnetlink_groups {
#define RTNLGRP_NSID RTNLGRP_NSID
RTNLGRP_MPLS_NETCONF,
#define RTNLGRP_MPLS_NETCONF RTNLGRP_MPLS_NETCONF
RTNLGRP_IPV4_MROUTE_R,
#define RTNLGRP_IPV4_MROUTE_R RTNLGRP_IPV4_MROUTE_R
RTNLGRP_IPV6_MROUTE_R,
#define RTNLGRP_IPV6_MROUTE_R RTNLGRP_IPV6_MROUTE_R
__RTNLGRP_MAX
};
#define RTNLGRP_MAX (__RTNLGRP_MAX - 1)

View File

@ -4218,6 +4218,18 @@ static void rtnetlink_rcv(struct sk_buff *skb)
rtnl_unlock();
}
static int rtnetlink_bind(struct net *net, int group)
{
switch (group) {
case RTNLGRP_IPV4_MROUTE_R:
case RTNLGRP_IPV6_MROUTE_R:
if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
return -EPERM;
break;
}
return 0;
}
static int rtnetlink_event(struct notifier_block *this, unsigned long event, void *ptr)
{
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
@ -4252,6 +4264,7 @@ static int __net_init rtnetlink_net_init(struct net *net)
.input = rtnetlink_rcv,
.cb_mutex = &rtnl_mutex,
.flags = NL_CFG_F_NONROOT_RECV,
.bind = rtnetlink_bind,
};
sk = netlink_kernel_create(net, NETLINK_ROUTE, &cfg);