mpls: Multicast route table change notifications

[karo-tx-linux.git] / net / mpls / af_mpls.c

diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c
index b4d7cec398d236f14b6f3329e4530a7796aaa7ec..75a994a5038136b0afaeb008dab95aefa0bb320a 100644 (file)
--- a/net/mpls/af_mpls.c
+++ b/net/mpls/af_mpls.c
@@ -36,6 +36,10 @@ struct mpls_route { /* next hop label forwarding entry */
 static int zero = 0;
 static int label_limit = (1 << 20) - 1;
 
+static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt,
+                      struct nlmsghdr *nlh, struct net *net, u32 portid,
+                      unsigned int nlm_flags);
+
 static struct mpls_route *mpls_route_input_rcu(struct net *net, unsigned index)
 {
        struct mpls_route *rt = NULL;
@@ -246,6 +250,20 @@ static void mpls_rt_free(struct mpls_route *rt)
                kfree_rcu(rt, rt_rcu);
 }
 
+static void mpls_notify_route(struct net *net, unsigned index,
+                             struct mpls_route *old, struct mpls_route *new,
+                             const struct nl_info *info)
+{
+       struct nlmsghdr *nlh = info ? info->nlh : NULL;
+       unsigned portid = info ? info->portid : 0;
+       int event = new ? RTM_NEWROUTE : RTM_DELROUTE;
+       struct mpls_route *rt = new ? new : old;
+       unsigned nlm_flags = (old && new) ? NLM_F_REPLACE : 0;
+       /* Ignore reserved labels for now */
+       if (rt && (index >= 16))
+               rtmsg_lfib(event, index, rt, nlh, net, portid, nlm_flags);
+}
+
 static void mpls_route_update(struct net *net, unsigned index,
                              struct net_device *dev, struct mpls_route *new,
                              const struct nl_info *info)
@@ -260,6 +278,8 @@ static void mpls_route_update(struct net *net, unsigned index,
                old = rt;
        }
 
+       mpls_notify_route(net, index, old, new, info);
+
        /* If we removed a route free it now */
        mpls_rt_free(old);
 }
@@ -692,6 +712,46 @@ static int mpls_dump_routes(struct sk_buff *skb, struct netlink_callback *cb)
        return skb->len;
 }
 
+static inline size_t lfib_nlmsg_size(struct mpls_route *rt)
+{
+       size_t payload =
+               NLMSG_ALIGN(sizeof(struct rtmsg))
+               + nla_total_size(2 + rt->rt_via_alen)   /* RTA_VIA */
+               + nla_total_size(4);                    /* RTA_DST */
+       if (rt->rt_labels)                              /* RTA_NEWDST */
+               payload += nla_total_size(rt->rt_labels * 4);
+       if (rt->rt_dev)                                 /* RTA_OIF */
+               payload += nla_total_size(4);
+       return payload;
+}
+
+static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt,
+                      struct nlmsghdr *nlh, struct net *net, u32 portid,
+                      unsigned int nlm_flags)
+{
+       struct sk_buff *skb;
+       u32 seq = nlh ? nlh->nlmsg_seq : 0;
+       int err = -ENOBUFS;
+
+       skb = nlmsg_new(lfib_nlmsg_size(rt), GFP_KERNEL);
+       if (skb == NULL)
+               goto errout;
+
+       err = mpls_dump_route(skb, portid, seq, event, label, rt, nlm_flags);
+       if (err < 0) {
+               /* -EMSGSIZE implies BUG in lfib_nlmsg_size */
+               WARN_ON(err == -EMSGSIZE);
+               kfree_skb(skb);
+               goto errout;
+       }
+       rtnl_notify(skb, net, portid, RTNLGRP_MPLS_ROUTE, nlh, GFP_KERNEL);
+
+       return;
+errout:
+       if (err < 0)
+               rtnl_set_sk_err(net, RTNLGRP_MPLS_ROUTE, err);
+}
+
 static int resize_platform_label_table(struct net *net, size_t limit)
 {
        size_t size = sizeof(struct mpls_route *) * limit;