ipv6: fib: Add in-kernel notifications for route add / delete

As with IPv4, allow listeners of the FIB notification chain to receive
notifications whenever a route is added, replaced or deleted. This is
done by placing calls to the FIB notification chain in the two lowest
level functions that end up performing these operations - namely,
fib6_add_rt2node() and fib6_del_route().

Unlike IPv4, APPEND notifications aren't sent as the kernel doesn't
distinguish between "append" (NLM_F_CREATE|NLM_F_APPEND) and "prepend"
(NLM_F_CREATE). If NLM_F_EXCL isn't set, duplicate routes are always
added after the existing duplicate routes.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/ip6_fib.h b/include/net/ip6_fib.h
index be8ddf3253dcf671dbbac81aaf334d087806a63c..e2b292b79e99bd39829e30e8d98a48295a165b28 100644 (file)
--- a/include/net/ip6_fib.h
+++ b/include/net/ip6_fib.h
@@ -258,6 +258,11 @@ typedef struct rt6_info *(*pol_lookup_t)(struct net *,
                                         struct fib6_table *,
                                         struct flowi6 *, int);
 
+struct fib6_entry_notifier_info {
+       struct fib_notifier_info info; /* must be first */
+       struct rt6_info *rt;
+};
+
 /*
  *     exported functions
  */

diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index f93976e3f65c3185b1e4f1d1ef2994d4f2c1fc93..595a57cbbc7ba855a6d2b2feb2ed9fdd236b45b9 100644 (file)
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -33,6 +33,7 @@
 #include <net/ndisc.h>
 #include <net/addrconf.h>
 #include <net/lwtunnel.h>
+#include <net/fib_notifier.h>
 
 #include <net/ip6_fib.h>
 #include <net/ip6_route.h>
@@ -302,6 +303,17 @@ static void __net_init fib6_tables_init(struct net *net)
 
 #endif
 
+static int call_fib6_entry_notifiers(struct net *net,
+                                    enum fib_event_type event_type,
+                                    struct rt6_info *rt)
+{
+       struct fib6_entry_notifier_info info = {
+               .rt = rt,
+       };
+
+       return call_fib6_notifiers(net, event_type, &info.info);
+}
+
 static int fib6_dump_node(struct fib6_walker *w)
 {
        int res;
@@ -879,6 +891,8 @@ add:
                *ins = rt;
                rt->rt6i_node = fn;
                atomic_inc(&rt->rt6i_ref);
+               call_fib6_entry_notifiers(info->nl_net, FIB_EVENT_ENTRY_ADD,
+                                         rt);
                if (!info->skip_notify)
                        inet6_rt_notify(RTM_NEWROUTE, rt, info, nlflags);
                info->nl_net->ipv6.rt6_stats->fib_rt_entries++;
@@ -906,6 +920,8 @@ add:
                rt->rt6i_node = fn;
                rt->dst.rt6_next = iter->dst.rt6_next;
                atomic_inc(&rt->rt6i_ref);
+               call_fib6_entry_notifiers(info->nl_net, FIB_EVENT_ENTRY_REPLACE,
+                                         rt);
                if (!info->skip_notify)
                        inet6_rt_notify(RTM_NEWROUTE, rt, info, NLM_F_REPLACE);
                if (!(fn->fn_flags & RTN_RTINFO)) {
@@ -1459,6 +1475,7 @@ static void fib6_del_route(struct fib6_node *fn, struct rt6_info **rtp,
 
        fib6_purge_rt(rt, fn, net);
 
+       call_fib6_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, rt);
        if (!info->skip_notify)
                inet6_rt_notify(RTM_DELROUTE, rt, info, 0);
        rt6_release(rt);