ipv6: export function to send route updates
Add fib6_rt_update to send RTM_NEWROUTE with NLM_F_REPLACE set. This
helper will be used by the nexthop code to notify userspace of routes
that are impacted when a nexthop config is updated via replace.
This notification is needed for legacy apps that do not understand
the new nexthop object. Apps that are nexthop aware can use the
RTA_NH_ID attribute in the route notification to just ignore it.
In the future this should be wrapped in a sysctl to allow OS'es that
are fully updated to avoid the notificaton storm.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 7a014ca..c52a7f4 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -5123,6 +5123,38 @@ void inet6_rt_notify(int event, struct fib6_info *rt, struct nl_info *info,
rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
}
+void fib6_rt_update(struct net *net, struct fib6_info *rt,
+ struct nl_info *info)
+{
+ u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0;
+ struct sk_buff *skb;
+ int err = -ENOBUFS;
+
+ /* call_fib6_entry_notifiers will be removed when in-kernel notifier
+ * is implemented and supported for nexthop objects
+ */
+ call_fib6_entry_notifiers(net, FIB_EVENT_ENTRY_REPLACE, rt, NULL);
+
+ skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
+ if (!skb)
+ goto errout;
+
+ err = rt6_fill_node(net, skb, rt, NULL, NULL, NULL, 0,
+ RTM_NEWROUTE, info->portid, seq, NLM_F_REPLACE);
+ if (err < 0) {
+ /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
+ WARN_ON(err == -EMSGSIZE);
+ kfree_skb(skb);
+ goto errout;
+ }
+ rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
+ info->nlh, gfp_any());
+ return;
+errout:
+ if (err < 0)
+ rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
+}
+
static int ip6_route_dev_notify(struct notifier_block *this,
unsigned long event, void *ptr)
{