netconf: advertise mc_forwarding status

This patch advertise the MC_FORWARDING status for IPv4 and IPv6.
This field is readonly, only multicast engine in the kernel updates it.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 20 insertions, 2 deletions

diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index e13183abd7f6..cc06a47f1216 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -1453,6 +1453,8 @@ static int inet_netconf_msgsize_devconf(int type)
                 size += nla_total_size(4);
         if (type == -1 || type == NETCONFA_RP_FILTER)
                 size += nla_total_size(4);
+        if (type == -1 || type == NETCONFA_MC_FORWARDING)
+                size += nla_total_size(4);
 
         return size;
 }
@@ -1485,6 +1487,10 @@ static int inet_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
             nla_put_s32(skb, NETCONFA_RP_FILTER,
                         IPV4_DEVCONF(*devconf, RP_FILTER)) < 0)
                 goto nla_put_failure;
+        if ((type == -1 || type == NETCONFA_MC_FORWARDING) &&
+            nla_put_s32(skb, NETCONFA_MC_FORWARDING,
+                        IPV4_DEVCONF(*devconf, MC_FORWARDING)) < 0)
+                goto nla_put_failure;
 
         return nlmsg_end(skb, nlh);
 
@@ -1493,8 +1499,8 @@ nla_put_failure:
         return -EMSGSIZE;
 }
 
-static void inet_netconf_notify_devconf(struct net *net, int type, int ifindex,
-                                        struct ipv4_devconf *devconf)
+void inet_netconf_notify_devconf(struct net *net, int type, int ifindex,
+                                 struct ipv4_devconf *devconf)
 {
         struct sk_buff *skb;
         int err = -ENOBUFS;
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 58e4160fdcee..0c452e3fdc1b 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -65,6 +65,7 @@
 #include <net/checksum.h>
 #include <net/netlink.h>
 #include <net/fib_rules.h>
+#include <linux/netconf.h>
 
 #if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
 #define CONFIG_IP_PIMSM 1
@@ -582,6 +583,9 @@ static int vif_delete(struct mr_table *mrt, int vifi, int notify,
         in_dev = __in_dev_get_rtnl(dev);
         if (in_dev) {
                 IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)--;
+                inet_netconf_notify_devconf(dev_net(dev),
+                                            NETCONFA_MC_FORWARDING,
+                                            dev->ifindex, &in_dev->cnf);
                 ip_rt_multicast_event(in_dev);
         }
 
@@ -772,6 +776,8 @@ static int vif_add(struct net *net, struct mr_table *mrt,
                 return -EADDRNOTAVAIL;
         }
         IPV4_DEVCONF(in_dev->cnf, MC_FORWARDING)++;
+        inet_netconf_notify_devconf(net, NETCONFA_MC_FORWARDING, dev->ifindex,
+                                    &in_dev->cnf);
         ip_rt_multicast_event(in_dev);
 
         /* Fill in the VIF structures */
@@ -1185,6 +1191,9 @@ static void mrtsock_destruct(struct sock *sk)
         ipmr_for_each_table(mrt, net) {
                 if (sk == rtnl_dereference(mrt->mroute_sk)) {
                         IPV4_DEVCONF_ALL(net, MC_FORWARDING)--;
+                        inet_netconf_notify_devconf(net, NETCONFA_MC_FORWARDING,
+                                                    NETCONFA_IFINDEX_ALL,
+                                                    net->ipv4.devconf_all);
                         RCU_INIT_POINTER(mrt->mroute_sk, NULL);
                         mroute_clean_tables(mrt);
                 }
@@ -1236,6 +1245,9 @@ int ip_mroute_setsockopt(struct sock *sk, int optname, char __user *optval, unsi
                 if (ret == 0) {
                         rcu_assign_pointer(mrt->mroute_sk, sk);
                         IPV4_DEVCONF_ALL(net, MC_FORWARDING)++;
+                        inet_netconf_notify_devconf(net, NETCONFA_MC_FORWARDING,
+                                                    NETCONFA_IFINDEX_ALL,
+                                                    net->ipv4.devconf_all);
                 }
                 rtnl_unlock();
                 return ret;