ip6mr: advertise new mfc entries via rtnl

This patch allows to monitor mf6c activities via rtnetlink. To avoid parsing two times the mf6c oifs, we use maxvif to allocate the rtnl msg, thus we may allocate some superfluous space. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>

ip6mr: advertise new mfc entries via rtnl
This patch allows to monitor mf6c activities via rtnetlink. To avoid parsing two times the mf6c oifs, we use maxvif to allocate the rtnl msg, thus we may allocate some superfluous space. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Nicolas Dichtel · David S. Miller
1 parent 8cd3ac9f9b
Showing 1 changed file with 59 additions and 4 deletions Side-by-side Diff
net/ipv6/ip6mr.c
@@ -116,6 +116,8 @@
 			      mifi_t mifi, int assert);
 static int __ip6mr_fill_mroute(struct mr6_table *mrt, struct sk_buff *skb,
 			       struct mfc6_cache *c, struct rtmsg *rtm);
+static void mr6_netlink_event(struct mr6_table *mrt, struct mfc6_cache *mfc,
+			      int cmd);
 static int ip6mr_rtm_dumproute(struct sk_buff *skb,
 			       struct netlink_callback *cb);
 static void mroute_clean_tables(struct mr6_table *mrt);
@@ -870,6 +872,7 @@
 		}
  
 		list_del(&c->list);
+		mr6_netlink_event(mrt, c, RTM_DELROUTE);
 		ip6mr_destroy_unres(mrt, c);
 	}
  
@@ -1220,6 +1223,7 @@
  
 		atomic_inc(&mrt->cache_resolve_queue_len);
 		list_add(&c->list, &mrt->mfc6_unres_queue);
+		mr6_netlink_event(mrt, c, RTM_NEWROUTE);
  
 		ipmr_do_expire_process(mrt);
 	}
@@ -1257,6 +1261,7 @@
 			list_del(&c->list);
 			write_unlock_bh(&mrt_lock);
  
+			mr6_netlink_event(mrt, c, RTM_DELROUTE);
 			ip6mr_cache_free(c);
 			return 0;
 		}
@@ -1421,6 +1426,7 @@
 		if (!mrtsock)
 			c->mfc_flags |= MFC_STATIC;
 		write_unlock_bh(&mrt_lock);
+		mr6_netlink_event(mrt, c, RTM_NEWROUTE);
 		return 0;
 	}
  
@@ -1465,6 +1471,7 @@
 		ip6mr_cache_resolve(net, mrt, uc, c);
 		ip6mr_cache_free(uc);
 	}
+	mr6_netlink_event(mrt, c, RTM_NEWROUTE);
 	return 0;
 }
  
@@ -1498,6 +1505,7 @@
 			list_del(&c->list);
 			write_unlock_bh(&mrt_lock);
  
+			mr6_netlink_event(mrt, c, RTM_DELROUTE);
 			ip6mr_cache_free(c);
 		}
 	}
@@ -1506,6 +1514,7 @@
 		spin_lock_bh(&mfc_unres_lock);
 		list_for_each_entry_safe(c, next, &mrt->mfc6_unres_queue, list) {
 			list_del(&c->list);
+			mr6_netlink_event(mrt, c, RTM_DELROUTE);
 			ip6mr_destroy_unres(mrt, c);
 		}
 		spin_unlock_bh(&mfc_unres_lock);
  
@@ -2231,13 +2240,13 @@
 }
  
 static int ip6mr_fill_mroute(struct mr6_table *mrt, struct sk_buff *skb,
-			     u32 portid, u32 seq, struct mfc6_cache *c)
+			     u32 portid, u32 seq, struct mfc6_cache *c, int cmd)
 {
 	struct nlmsghdr *nlh;
 	struct rtmsg *rtm;
 	int err;
  
-	nlh = nlmsg_put(skb, portid, seq, RTM_NEWROUTE, sizeof(*rtm), NLM_F_MULTI);
+	nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), NLM_F_MULTI);
 	if (nlh == NULL)
 		return -EMSGSIZE;
  
@@ -2272,6 +2281,52 @@
 	return -EMSGSIZE;
 }
  
+static int mr6_msgsize(bool unresolved, int maxvif)
+{
+	size_t len =
+		NLMSG_ALIGN(sizeof(struct rtmsg))
+		+ nla_total_size(4)	/* RTA_TABLE */
+		+ nla_total_size(sizeof(struct in6_addr))	/* RTA_SRC */
+		+ nla_total_size(sizeof(struct in6_addr))	/* RTA_DST */
+		;
+
+	if (!unresolved)
+		len = len
+		      + nla_total_size(4)	/* RTA_IIF */
+		      + nla_total_size(0)	/* RTA_MULTIPATH */
+		      + maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
+						/* RTA_MFC_STATS */
+		      + nla_total_size(sizeof(struct rta_mfc_stats))
+		;
+
+	return len;
+}
+
+static void mr6_netlink_event(struct mr6_table *mrt, struct mfc6_cache *mfc,
+			      int cmd)
+{
+	struct net *net = read_pnet(&mrt->net);
+	struct sk_buff *skb;
+	int err = -ENOBUFS;
+
+	skb = nlmsg_new(mr6_msgsize(mfc->mf6c_parent >= MAXMIFS, mrt->maxvif),
+			GFP_ATOMIC);
+	if (skb == NULL)
+		goto errout;
+
+	err = ip6mr_fill_mroute(mrt, skb, 0, 0, mfc, cmd);
+	if (err < 0)
+		goto errout;
+
+	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_MROUTE, NULL, GFP_ATOMIC);
+	return;
+
+errout:
+	kfree_skb(skb);
+	if (err < 0)
+		rtnl_set_sk_err(net, RTNLGRP_IPV6_MROUTE, err);
+}
+
 static int ip6mr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb)
 {
 	struct net *net = sock_net(skb->sk);
@@ -2298,7 +2353,7 @@
 				if (ip6mr_fill_mroute(mrt, skb,
 						      NETLINK_CB(cb->skb).portid,
 						      cb->nlh->nlmsg_seq,
-						      mfc) < 0)
+						      mfc, RTM_NEWROUTE) < 0)
 					goto done;
 next_entry:
 				e++;
@@ -2312,7 +2367,7 @@
 			if (ip6mr_fill_mroute(mrt, skb,
 					      NETLINK_CB(cb->skb).portid,
 					      cb->nlh->nlmsg_seq,
-					      mfc) < 0) {
+					      mfc, RTM_NEWROUTE) < 0) {
 				spin_unlock_bh(&mfc_unres_lock);
 				goto done;
 			}
...	...	@@ -116,6 +116,8 @@
116	116	mifi_t mifi, int assert);
117	117	static int __ip6mr_fill_mroute(struct mr6_table mrt, struct sk_buff skb,
118	118	struct mfc6_cache c, struct rtmsg rtm);
	119	+static void mr6_netlink_event(struct mr6_table mrt, struct mfc6_cache mfc,
	120	+ int cmd);
119	121	static int ip6mr_rtm_dumproute(struct sk_buff *skb,
120	122	struct netlink_callback *cb);
121	123	static void mroute_clean_tables(struct mr6_table *mrt);
...	...	@@ -870,6 +872,7 @@
870	872	}
871	873
872	874	list_del(&c->list);
	875	+ mr6_netlink_event(mrt, c, RTM_DELROUTE);
873	876	ip6mr_destroy_unres(mrt, c);
874	877	}
875	878
...	...	@@ -1220,6 +1223,7 @@
1220	1223
1221	1224	atomic_inc(&mrt->cache_resolve_queue_len);
1222	1225	list_add(&c->list, &mrt->mfc6_unres_queue);
	1226	+ mr6_netlink_event(mrt, c, RTM_NEWROUTE);
1223	1227
1224	1228	ipmr_do_expire_process(mrt);
1225	1229	}
...	...	@@ -1257,6 +1261,7 @@
1257	1261	list_del(&c->list);
1258	1262	write_unlock_bh(&mrt_lock);
1259	1263
	1264	+ mr6_netlink_event(mrt, c, RTM_DELROUTE);
1260	1265	ip6mr_cache_free(c);
1261	1266	return 0;
1262	1267	}
...	...	@@ -1421,6 +1426,7 @@
1421	1426	if (!mrtsock)
1422	1427	c->mfc_flags \|= MFC_STATIC;
1423	1428	write_unlock_bh(&mrt_lock);
	1429	+ mr6_netlink_event(mrt, c, RTM_NEWROUTE);
1424	1430	return 0;
1425	1431	}
1426	1432
...	...	@@ -1465,6 +1471,7 @@
1465	1471	ip6mr_cache_resolve(net, mrt, uc, c);
1466	1472	ip6mr_cache_free(uc);
1467	1473	}
	1474	+ mr6_netlink_event(mrt, c, RTM_NEWROUTE);
1468	1475	return 0;
1469	1476	}
1470	1477
...	...	@@ -1498,6 +1505,7 @@
1498	1505	list_del(&c->list);
1499	1506	write_unlock_bh(&mrt_lock);
1500	1507
	1508	+ mr6_netlink_event(mrt, c, RTM_DELROUTE);
1501	1509	ip6mr_cache_free(c);
1502	1510	}
1503	1511	}
...	...	@@ -1506,6 +1514,7 @@
1506	1514	spin_lock_bh(&mfc_unres_lock);
1507	1515	list_for_each_entry_safe(c, next, &mrt->mfc6_unres_queue, list) {
1508	1516	list_del(&c->list);
	1517	+ mr6_netlink_event(mrt, c, RTM_DELROUTE);
1509	1518	ip6mr_destroy_unres(mrt, c);
1510	1519	}
1511	1520	spin_unlock_bh(&mfc_unres_lock);
1512	1521
...	...	@@ -2231,13 +2240,13 @@
2231	2240	}
2232	2241
2233	2242	static int ip6mr_fill_mroute(struct mr6_table mrt, struct sk_buff skb,
2234		- u32 portid, u32 seq, struct mfc6_cache *c)
	2243	+ u32 portid, u32 seq, struct mfc6_cache *c, int cmd)
2235	2244	{
2236	2245	struct nlmsghdr *nlh;
2237	2246	struct rtmsg *rtm;
2238	2247	int err;
2239	2248
2240		- nlh = nlmsg_put(skb, portid, seq, RTM_NEWROUTE, sizeof(*rtm), NLM_F_MULTI);
	2249	+ nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rtm), NLM_F_MULTI);
2241	2250	if (nlh == NULL)
2242	2251	return -EMSGSIZE;
2243	2252
...	...	@@ -2272,6 +2281,52 @@
2272	2281	return -EMSGSIZE;
2273	2282	}
2274	2283
	2284	+static int mr6_msgsize(bool unresolved, int maxvif)
	2285	+{
	2286	+ size_t len =
	2287	+ NLMSG_ALIGN(sizeof(struct rtmsg))
	2288	+ + nla_total_size(4) /* RTA_TABLE */
	2289	+ + nla_total_size(sizeof(struct in6_addr)) /* RTA_SRC */
	2290	+ + nla_total_size(sizeof(struct in6_addr)) /* RTA_DST */
	2291	+ ;
	2292	+
	2293	+ if (!unresolved)
	2294	+ len = len
	2295	+ + nla_total_size(4) /* RTA_IIF */
	2296	+ + nla_total_size(0) /* RTA_MULTIPATH */
	2297	+ + maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
	2298	+ /* RTA_MFC_STATS */
	2299	+ + nla_total_size(sizeof(struct rta_mfc_stats))
	2300	+ ;
	2301	+
	2302	+ return len;
	2303	+}
	2304	+
	2305	+static void mr6_netlink_event(struct mr6_table mrt, struct mfc6_cache mfc,
	2306	+ int cmd)
	2307	+{
	2308	+ struct net *net = read_pnet(&mrt->net);
	2309	+ struct sk_buff *skb;
	2310	+ int err = -ENOBUFS;
	2311	+
	2312	+ skb = nlmsg_new(mr6_msgsize(mfc->mf6c_parent >= MAXMIFS, mrt->maxvif),
	2313	+ GFP_ATOMIC);
	2314	+ if (skb == NULL)
	2315	+ goto errout;
	2316	+
	2317	+ err = ip6mr_fill_mroute(mrt, skb, 0, 0, mfc, cmd);
	2318	+ if (err < 0)
	2319	+ goto errout;
	2320	+
	2321	+ rtnl_notify(skb, net, 0, RTNLGRP_IPV6_MROUTE, NULL, GFP_ATOMIC);
	2322	+ return;
	2323	+
	2324	+errout:
	2325	+ kfree_skb(skb);
	2326	+ if (err < 0)
	2327	+ rtnl_set_sk_err(net, RTNLGRP_IPV6_MROUTE, err);
	2328	+}
	2329	+
2275	2330	static int ip6mr_rtm_dumproute(struct sk_buff skb, struct netlink_callback cb)
2276	2331	{
2277	2332	struct net *net = sock_net(skb->sk);
...	...	@@ -2298,7 +2353,7 @@
2298	2353	if (ip6mr_fill_mroute(mrt, skb,
2299	2354	NETLINK_CB(cb->skb).portid,
2300	2355	cb->nlh->nlmsg_seq,
2301		- mfc) < 0)
	2356	+ mfc, RTM_NEWROUTE) < 0)
2302	2357	goto done;
2303	2358	next_entry:
2304	2359	e++;
...	...	@@ -2312,7 +2367,7 @@
2312	2367	if (ip6mr_fill_mroute(mrt, skb,
2313	2368	NETLINK_CB(cb->skb).portid,
2314	2369	cb->nlh->nlmsg_seq,
2315		- mfc) < 0) {
	2370	+ mfc, RTM_NEWROUTE) < 0) {
2316	2371	spin_unlock_bh(&mfc_unres_lock);
2317	2372	goto done;
2318	2373	}