1 From: Felix Fietkau <nbd@nbd.name>
2 Subject: [PATCH] bridge: multicast to unicast
4 Implement optinal multicast->unicast conversion for igmp snooping
6 --- a/net/bridge/br_multicast.c
7 +++ b/net/bridge/br_multicast.c
8 @@ -635,7 +635,8 @@ struct net_bridge_port_group *br_multica
9 struct net_bridge_port *port,
11 struct net_bridge_port_group __rcu *next,
12 - unsigned char state)
13 + unsigned char state,
14 + const unsigned char *src)
16 struct net_bridge_port_group *p;
18 @@ -650,12 +651,33 @@ struct net_bridge_port_group *br_multica
19 hlist_add_head(&p->mglist, &port->mglist);
20 setup_timer(&p->timer, br_multicast_port_group_expired,
22 + if ((port->flags & BR_MULTICAST_TO_UCAST) && src) {
23 + memcpy(p->eth_addr, src, ETH_ALEN);
29 +static bool br_port_group_equal(struct net_bridge_port_group *p,
30 + struct net_bridge_port *port,
31 + const unsigned char *src)
33 + if (p->port != port)
42 + return ether_addr_equal(src, p->eth_addr);
45 static int br_multicast_add_group(struct net_bridge *br,
46 struct net_bridge_port *port,
47 - struct br_ip *group)
48 + struct br_ip *group,
49 + const unsigned char *src)
51 struct net_bridge_mdb_entry *mp;
52 struct net_bridge_port_group *p;
53 @@ -682,13 +704,13 @@ static int br_multicast_add_group(struct
55 (p = mlock_dereference(*pp, br)) != NULL;
57 - if (p->port == port)
58 + if (br_port_group_equal(p, port, src))
60 if ((unsigned long)p->port < (unsigned long)port)
64 - p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY);
65 + p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY, src);
68 rcu_assign_pointer(*pp, p);
69 @@ -707,7 +729,7 @@ err:
70 static int br_ip4_multicast_add_group(struct net_bridge *br,
71 struct net_bridge_port *port,
74 + __u16 vid, const unsigned char *src)
76 struct br_ip br_group;
78 @@ -718,14 +740,14 @@ static int br_ip4_multicast_add_group(st
79 br_group.proto = htons(ETH_P_IP);
82 - return br_multicast_add_group(br, port, &br_group);
83 + return br_multicast_add_group(br, port, &br_group, src);
86 #if IS_ENABLED(CONFIG_IPV6)
87 static int br_ip6_multicast_add_group(struct net_bridge *br,
88 struct net_bridge_port *port,
89 const struct in6_addr *group,
91 + __u16 vid, const unsigned char *src)
93 struct br_ip br_group;
95 @@ -736,7 +758,7 @@ static int br_ip6_multicast_add_group(st
96 br_group.proto = htons(ETH_P_IPV6);
99 - return br_multicast_add_group(br, port, &br_group);
100 + return br_multicast_add_group(br, port, &br_group, src);
104 @@ -965,6 +987,7 @@ static int br_ip4_multicast_igmp3_report
108 + const unsigned char *src;
109 struct igmpv3_report *ih;
110 struct igmpv3_grec *grec;
112 @@ -1008,7 +1031,8 @@ static int br_ip4_multicast_igmp3_report
116 - err = br_ip4_multicast_add_group(br, port, group, vid);
117 + src = eth_hdr(skb)->h_source;
118 + err = br_ip4_multicast_add_group(br, port, group, vid, src);
122 @@ -1022,6 +1046,7 @@ static int br_ip6_multicast_mld2_report(
126 + const unsigned char *src;
127 struct icmp6hdr *icmp6h;
128 struct mld2_grec *grec;
130 @@ -1069,8 +1094,9 @@ static int br_ip6_multicast_mld2_report(
134 + src = eth_hdr(skb)->h_source;
135 err = br_ip6_multicast_add_group(br, port, &grec->grec_mca,
141 @@ -1406,7 +1432,8 @@ br_multicast_leave_group(struct net_brid
142 struct net_bridge_port *port,
144 struct bridge_mcast_other_query *other_query,
145 - struct bridge_mcast_own_query *own_query)
146 + struct bridge_mcast_own_query *own_query,
147 + const unsigned char *src)
149 struct net_bridge_mdb_htable *mdb;
150 struct net_bridge_mdb_entry *mp;
151 @@ -1456,7 +1483,7 @@ br_multicast_leave_group(struct net_brid
152 for (pp = &mp->ports;
153 (p = mlock_dereference(*pp, br)) != NULL;
155 - if (p->port != port)
156 + if (!br_port_group_equal(p, port, src))
159 rcu_assign_pointer(*pp, p->next);
160 @@ -1490,7 +1517,7 @@ br_multicast_leave_group(struct net_brid
161 for (p = mlock_dereference(mp->ports, br);
163 p = mlock_dereference(p->next, br)) {
164 - if (p->port != port)
165 + if (!br_port_group_equal(p, port, src))
168 if (!hlist_unhashed(&p->mglist) &&
169 @@ -1508,8 +1535,8 @@ out:
171 static void br_ip4_multicast_leave_group(struct net_bridge *br,
172 struct net_bridge_port *port,
175 + __be32 group, __u16 vid,
176 + const unsigned char *src)
178 struct br_ip br_group;
179 struct bridge_mcast_own_query *own_query;
180 @@ -1524,14 +1551,14 @@ static void br_ip4_multicast_leave_group
183 br_multicast_leave_group(br, port, &br_group, &br->ip4_other_query,
188 #if IS_ENABLED(CONFIG_IPV6)
189 static void br_ip6_multicast_leave_group(struct net_bridge *br,
190 struct net_bridge_port *port,
191 const struct in6_addr *group,
193 + __u16 vid, const unsigned char *src)
195 struct br_ip br_group;
196 struct bridge_mcast_own_query *own_query;
197 @@ -1546,7 +1573,7 @@ static void br_ip6_multicast_leave_group
200 br_multicast_leave_group(br, port, &br_group, &br->ip6_other_query,
206 @@ -1555,6 +1582,7 @@ static int br_multicast_ipv4_rcv(struct
210 + const unsigned char *src;
211 struct sk_buff *skb2 = skb;
212 const struct iphdr *iph;
214 @@ -1628,7 +1656,8 @@ static int br_multicast_ipv4_rcv(struct
215 case IGMP_HOST_MEMBERSHIP_REPORT:
216 case IGMPV2_HOST_MEMBERSHIP_REPORT:
217 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
218 - err = br_ip4_multicast_add_group(br, port, ih->group, vid);
219 + src = eth_hdr(skb)->h_source;
220 + err = br_ip4_multicast_add_group(br, port, ih->group, vid, src);
222 case IGMPV3_HOST_MEMBERSHIP_REPORT:
223 err = br_ip4_multicast_igmp3_report(br, port, skb2, vid);
224 @@ -1637,7 +1666,8 @@ static int br_multicast_ipv4_rcv(struct
225 err = br_ip4_multicast_query(br, port, skb2, vid);
227 case IGMP_HOST_LEAVE_MESSAGE:
228 - br_ip4_multicast_leave_group(br, port, ih->group, vid);
229 + src = eth_hdr(skb)->h_source;
230 + br_ip4_multicast_leave_group(br, port, ih->group, vid, src);
234 @@ -1655,6 +1685,7 @@ static int br_multicast_ipv6_rcv(struct
238 + const unsigned char *src;
239 struct sk_buff *skb2;
240 const struct ipv6hdr *ip6h;
242 @@ -1764,7 +1795,9 @@ static int br_multicast_ipv6_rcv(struct
244 mld = (struct mld_msg *)skb_transport_header(skb2);
245 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
246 - err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
247 + src = eth_hdr(skb)->h_source;
248 + err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid,
252 case ICMPV6_MLD2_REPORT:
253 @@ -1781,7 +1814,8 @@ static int br_multicast_ipv6_rcv(struct
256 mld = (struct mld_msg *)skb_transport_header(skb2);
257 - br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
258 + src = eth_hdr(skb)->h_source;
259 + br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid, src);
263 --- a/net/bridge/br_private.h
264 +++ b/net/bridge/br_private.h
265 @@ -112,6 +112,9 @@ struct net_bridge_port_group {
266 struct timer_list timer;
270 + unsigned char eth_addr[ETH_ALEN];
274 struct net_bridge_mdb_entry
275 @@ -173,6 +176,7 @@ struct net_bridge_port
276 #define BR_AUTO_MASK (BR_FLOOD | BR_LEARNING)
277 #define BR_PROMISC 0x00000080
278 #define BR_ISOLATE_MODE 0x00000100
279 +#define BR_MULTICAST_TO_UCAST 0x00000200
281 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
282 struct bridge_mcast_own_query ip4_own_query;
283 @@ -485,7 +489,8 @@ void br_multicast_free_pg(struct rcu_hea
284 struct net_bridge_port_group *
285 br_multicast_new_port_group(struct net_bridge_port *port, struct br_ip *group,
286 struct net_bridge_port_group __rcu *next,
287 - unsigned char state);
288 + unsigned char state,
289 + const unsigned char *src);
290 void br_mdb_init(void);
291 void br_mdb_uninit(void);
292 void br_mdb_notify(struct net_device *dev, struct net_bridge_port *port,
293 --- a/net/bridge/br_mdb.c
294 +++ b/net/bridge/br_mdb.c
295 @@ -342,7 +342,7 @@ static int br_mdb_add_group(struct net_b
299 - p = br_multicast_new_port_group(port, group, *pp, state);
300 + p = br_multicast_new_port_group(port, group, *pp, state, NULL);
303 rcu_assign_pointer(*pp, p);
304 --- a/net/bridge/br_forward.c
305 +++ b/net/bridge/br_forward.c
306 @@ -168,6 +168,34 @@ out:
310 +static struct net_bridge_port *maybe_deliver_addr(
311 + struct net_bridge_port *prev, struct net_bridge_port *p,
312 + struct sk_buff *skb, const unsigned char *addr,
313 + void (*__packet_hook)(const struct net_bridge_port *p,
314 + struct sk_buff *skb))
316 + struct net_device *dev = BR_INPUT_SKB_CB(skb)->brdev;
317 + const unsigned char *src = eth_hdr(skb)->h_source;
319 + if (!should_deliver(p, skb))
322 + /* Even with hairpin, no soliloquies - prevent breaking IPv6 DAD */
323 + if (skb->dev == p->dev && ether_addr_equal(src, addr))
326 + skb = skb_copy(skb, GFP_ATOMIC);
328 + dev->stats.tx_dropped++;
332 + memcpy(eth_hdr(skb)->h_dest, addr, ETH_ALEN);
333 + __packet_hook(p, skb);
338 /* called under bridge lock */
339 static void br_flood(struct net_bridge *br, struct sk_buff *skb,
340 struct sk_buff *skb0,
341 @@ -232,6 +260,7 @@ static void br_multicast_flood(struct ne
342 struct net_bridge_port *prev = NULL;
343 struct net_bridge_port_group *p;
344 struct hlist_node *rp;
345 + const unsigned char *addr;
347 rp = rcu_dereference(hlist_first_rcu(&br->router_list));
348 p = mdst ? rcu_dereference(mdst->ports) : NULL;
349 @@ -242,10 +271,19 @@ static void br_multicast_flood(struct ne
350 rport = rp ? hlist_entry(rp, struct net_bridge_port, rlist) :
353 - port = (unsigned long)lport > (unsigned long)rport ?
356 - prev = maybe_deliver(prev, port, skb, __packet_hook);
357 + if ((unsigned long)lport > (unsigned long)rport) {
359 + addr = p->unicast ? p->eth_addr : NULL;
366 + prev = maybe_deliver_addr(prev, port, skb, addr,
369 + prev = maybe_deliver(prev, port, skb, __packet_hook);
373 --- a/net/bridge/br_sysfs_if.c
374 +++ b/net/bridge/br_sysfs_if.c
375 @@ -187,6 +187,7 @@ static BRPORT_ATTR(multicast_router, S_I
376 store_multicast_router);
378 BRPORT_ATTR_FLAG(multicast_fast_leave, BR_MULTICAST_FAST_LEAVE);
379 +BRPORT_ATTR_FLAG(multicast_to_unicast, BR_MULTICAST_TO_UCAST);
382 static const struct brport_attribute *brport_attrs[] = {
383 @@ -213,6 +214,7 @@ static const struct brport_attribute *br
384 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
385 &brport_attr_multicast_router,
386 &brport_attr_multicast_fast_leave,
387 + &brport_attr_multicast_to_unicast,
389 &brport_attr_isolated,