OpenWrt – Rev 1
?pathlinks?
From: Felix Fietkau <nbd@nbd.name>
Subject: [PATCH] bridge: multicast to unicast
Implement optinal multicast->unicast conversion for igmp snooping
---
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -635,7 +635,8 @@ struct net_bridge_port_group *br_multica
struct net_bridge_port *port,
struct br_ip *group,
struct net_bridge_port_group __rcu *next,
- unsigned char state)
+ unsigned char state,
+ const unsigned char *src)
{
struct net_bridge_port_group *p;
@@ -650,12 +651,33 @@ struct net_bridge_port_group *br_multica
hlist_add_head(&p->mglist, &port->mglist);
setup_timer(&p->timer, br_multicast_port_group_expired,
(unsigned long)p);
+ if ((port->flags & BR_MULTICAST_TO_UCAST) && src) {
+ memcpy(p->eth_addr, src, ETH_ALEN);
+ p->unicast = true;
+ }
return p;
}
+static bool br_port_group_equal(struct net_bridge_port_group *p,
+ struct net_bridge_port *port,
+ const unsigned char *src)
+{
+ if (p->port != port)
+ return false;
+
+ if (!p->unicast)
+ return true;
+
+ if (!src)
+ return false;
+
+ return ether_addr_equal(src, p->eth_addr);
+}
+
static int br_multicast_add_group(struct net_bridge *br,
struct net_bridge_port *port,
- struct br_ip *group)
+ struct br_ip *group,
+ const unsigned char *src)
{
struct net_bridge_mdb_entry *mp;
struct net_bridge_port_group *p;
@@ -682,13 +704,13 @@ static int br_multicast_add_group(struct
for (pp = &mp->ports;
(p = mlock_dereference(*pp, br)) != NULL;
pp = &p->next) {
- if (p->port == port)
+ if (br_port_group_equal(p, port, src))
goto found;
if ((unsigned long)p->port < (unsigned long)port)
break;
}
- p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY);
+ p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY, src);
if (unlikely(!p))
goto err;
rcu_assign_pointer(*pp, p);
@@ -707,7 +729,7 @@ err:
static int br_ip4_multicast_add_group(struct net_bridge *br,
struct net_bridge_port *port,
__be32 group,
- __u16 vid)
+ __u16 vid, const unsigned char *src)
{
struct br_ip br_group;
@@ -718,14 +740,14 @@ static int br_ip4_multicast_add_group(st
br_group.proto = htons(ETH_P_IP);
br_group.vid = vid;
- return br_multicast_add_group(br, port, &br_group);
+ return br_multicast_add_group(br, port, &br_group, src);
}
#if IS_ENABLED(CONFIG_IPV6)
static int br_ip6_multicast_add_group(struct net_bridge *br,
struct net_bridge_port *port,
const struct in6_addr *group,
- __u16 vid)
+ __u16 vid, const unsigned char *src)
{
struct br_ip br_group;
@@ -736,7 +758,7 @@ static int br_ip6_multicast_add_group(st
br_group.proto = htons(ETH_P_IPV6);
br_group.vid = vid;
- return br_multicast_add_group(br, port, &br_group);
+ return br_multicast_add_group(br, port, &br_group, src);
}
#endif
@@ -965,6 +987,7 @@ static int br_ip4_multicast_igmp3_report
struct sk_buff *skb,
u16 vid)
{
+ const unsigned char *src;
struct igmpv3_report *ih;
struct igmpv3_grec *grec;
int i;
@@ -1008,7 +1031,8 @@ static int br_ip4_multicast_igmp3_report
continue;
}
- err = br_ip4_multicast_add_group(br, port, group, vid);
+ src = eth_hdr(skb)->h_source;
+ err = br_ip4_multicast_add_group(br, port, group, vid, src);
if (err)
break;
}
@@ -1022,6 +1046,7 @@ static int br_ip6_multicast_mld2_report(
struct sk_buff *skb,
u16 vid)
{
+ const unsigned char *src;
struct icmp6hdr *icmp6h;
struct mld2_grec *grec;
int i;
@@ -1069,8 +1094,9 @@ static int br_ip6_multicast_mld2_report(
continue;
}
+ src = eth_hdr(skb)->h_source;
err = br_ip6_multicast_add_group(br, port, &grec->grec_mca,
- vid);
+ vid, src);
if (err)
break;
}
@@ -1406,7 +1432,8 @@ br_multicast_leave_group(struct net_brid
struct net_bridge_port *port,
struct br_ip *group,
struct bridge_mcast_other_query *other_query,
- struct bridge_mcast_own_query *own_query)
+ struct bridge_mcast_own_query *own_query,
+ const unsigned char *src)
{
struct net_bridge_mdb_htable *mdb;
struct net_bridge_mdb_entry *mp;
@@ -1456,7 +1483,7 @@ br_multicast_leave_group(struct net_brid
for (pp = &mp->ports;
(p = mlock_dereference(*pp, br)) != NULL;
pp = &p->next) {
- if (p->port != port)
+ if (!br_port_group_equal(p, port, src))
continue;
rcu_assign_pointer(*pp, p->next);
@@ -1490,7 +1517,7 @@ br_multicast_leave_group(struct net_brid
for (p = mlock_dereference(mp->ports, br);
p != NULL;
p = mlock_dereference(p->next, br)) {
- if (p->port != port)
+ if (!br_port_group_equal(p, port, src))
continue;
if (!hlist_unhashed(&p->mglist) &&
@@ -1508,8 +1535,8 @@ out:
static void br_ip4_multicast_leave_group(struct net_bridge *br,
struct net_bridge_port *port,
- __be32 group,
- __u16 vid)
+ __be32 group, __u16 vid,
+ const unsigned char *src)
{
struct br_ip br_group;
struct bridge_mcast_own_query *own_query;
@@ -1524,14 +1551,14 @@ static void br_ip4_multicast_leave_group
br_group.vid = vid;
br_multicast_leave_group(br, port, &br_group, &br->ip4_other_query,
- own_query);
+ own_query, src);
}
#if IS_ENABLED(CONFIG_IPV6)
static void br_ip6_multicast_leave_group(struct net_bridge *br,
struct net_bridge_port *port,
const struct in6_addr *group,
- __u16 vid)
+ __u16 vid, const unsigned char *src)
{
struct br_ip br_group;
struct bridge_mcast_own_query *own_query;
@@ -1546,7 +1573,7 @@ static void br_ip6_multicast_leave_group
br_group.vid = vid;
br_multicast_leave_group(br, port, &br_group, &br->ip6_other_query,
- own_query);
+ own_query, src);
}
#endif
@@ -1555,6 +1582,7 @@ static int br_multicast_ipv4_rcv(struct
struct sk_buff *skb,
u16 vid)
{
+ const unsigned char *src;
struct sk_buff *skb2 = skb;
const struct iphdr *iph;
struct igmphdr *ih;
@@ -1628,7 +1656,8 @@ static int br_multicast_ipv4_rcv(struct
case IGMP_HOST_MEMBERSHIP_REPORT:
case IGMPV2_HOST_MEMBERSHIP_REPORT:
BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
- err = br_ip4_multicast_add_group(br, port, ih->group, vid);
+ src = eth_hdr(skb)->h_source;
+ err = br_ip4_multicast_add_group(br, port, ih->group, vid, src);
break;
case IGMPV3_HOST_MEMBERSHIP_REPORT:
err = br_ip4_multicast_igmp3_report(br, port, skb2, vid);
@@ -1637,7 +1666,8 @@ static int br_multicast_ipv4_rcv(struct
err = br_ip4_multicast_query(br, port, skb2, vid);
break;
case IGMP_HOST_LEAVE_MESSAGE:
- br_ip4_multicast_leave_group(br, port, ih->group, vid);
+ src = eth_hdr(skb)->h_source;
+ br_ip4_multicast_leave_group(br, port, ih->group, vid, src);
break;
}
@@ -1655,6 +1685,7 @@ static int br_multicast_ipv6_rcv(struct
struct sk_buff *skb,
u16 vid)
{
+ const unsigned char *src;
struct sk_buff *skb2;
const struct ipv6hdr *ip6h;
u8 icmp6_type;
@@ -1764,7 +1795,9 @@ static int br_multicast_ipv6_rcv(struct
}
mld = (struct mld_msg *)skb_transport_header(skb2);
BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
- err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
+ src = eth_hdr(skb)->h_source;
+ err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid,
+ src);
break;
}
case ICMPV6_MLD2_REPORT:
@@ -1781,7 +1814,8 @@ static int br_multicast_ipv6_rcv(struct
goto out;
}
mld = (struct mld_msg *)skb_transport_header(skb2);
- br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
+ src = eth_hdr(skb)->h_source;
+ br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid, src);
}
}
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -112,6 +112,9 @@ struct net_bridge_port_group {
struct timer_list timer;
struct br_ip addr;
unsigned char state;
+
+ unsigned char eth_addr[ETH_ALEN];
+ bool unicast;
};
struct net_bridge_mdb_entry
@@ -173,6 +176,7 @@ struct net_bridge_port
#define BR_AUTO_MASK (BR_FLOOD | BR_LEARNING)
#define BR_PROMISC 0x00000080
#define BR_ISOLATE_MODE 0x00000100
+#define BR_MULTICAST_TO_UCAST 0x00000200
#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
struct bridge_mcast_own_query ip4_own_query;
@@ -485,7 +489,8 @@ void br_multicast_free_pg(struct rcu_hea
struct net_bridge_port_group *
br_multicast_new_port_group(struct net_bridge_port *port, struct br_ip *group,
struct net_bridge_port_group __rcu *next,
- unsigned char state);
+ unsigned char state,
+ const unsigned char *src);
void br_mdb_init(void);
void br_mdb_uninit(void);
void br_mdb_notify(struct net_device *dev, struct net_bridge_port *port,
--- a/net/bridge/br_mdb.c
+++ b/net/bridge/br_mdb.c
@@ -342,7 +342,7 @@ static int br_mdb_add_group(struct net_b
break;
}
- p = br_multicast_new_port_group(port, group, *pp, state);
+ p = br_multicast_new_port_group(port, group, *pp, state, NULL);
if (unlikely(!p))
return -ENOMEM;
rcu_assign_pointer(*pp, p);
--- a/net/bridge/br_forward.c
+++ b/net/bridge/br_forward.c
@@ -168,6 +168,34 @@ out:
return p;
}
+static struct net_bridge_port *maybe_deliver_addr(
+ struct net_bridge_port *prev, struct net_bridge_port *p,
+ struct sk_buff *skb, const unsigned char *addr,
+ void (*__packet_hook)(const struct net_bridge_port *p,
+ struct sk_buff *skb))
+{
+ struct net_device *dev = BR_INPUT_SKB_CB(skb)->brdev;
+ const unsigned char *src = eth_hdr(skb)->h_source;
+
+ if (!should_deliver(p, skb))
+ return prev;
+
+ /* Even with hairpin, no soliloquies - prevent breaking IPv6 DAD */
+ if (skb->dev == p->dev && ether_addr_equal(src, addr))
+ return prev;
+
+ skb = skb_copy(skb, GFP_ATOMIC);
+ if (!skb) {
+ dev->stats.tx_dropped++;
+ return prev;
+ }
+
+ memcpy(eth_hdr(skb)->h_dest, addr, ETH_ALEN);
+ __packet_hook(p, skb);
+
+ return prev;
+}
+
/* called under bridge lock */
static void br_flood(struct net_bridge *br, struct sk_buff *skb,
struct sk_buff *skb0,
@@ -232,6 +260,7 @@ static void br_multicast_flood(struct ne
struct net_bridge_port *prev = NULL;
struct net_bridge_port_group *p;
struct hlist_node *rp;
+ const unsigned char *addr;
rp = rcu_dereference(hlist_first_rcu(&br->router_list));
p = mdst ? rcu_dereference(mdst->ports) : NULL;
@@ -242,10 +271,19 @@ static void br_multicast_flood(struct ne
rport = rp ? hlist_entry(rp, struct net_bridge_port, rlist) :
NULL;
- port = (unsigned long)lport > (unsigned long)rport ?
- lport : rport;
-
- prev = maybe_deliver(prev, port, skb, __packet_hook);
+ if ((unsigned long)lport > (unsigned long)rport) {
+ port = lport;
+ addr = p->unicast ? p->eth_addr : NULL;
+ } else {
+ port = rport;
+ addr = NULL;
+ }
+
+ if (addr)
+ prev = maybe_deliver_addr(prev, port, skb, addr,
+ __packet_hook);
+ else
+ prev = maybe_deliver(prev, port, skb, __packet_hook);
if (IS_ERR(prev))
goto out;
--- a/net/bridge/br_sysfs_if.c
+++ b/net/bridge/br_sysfs_if.c
@@ -187,6 +187,7 @@ static BRPORT_ATTR(multicast_router, S_I
store_multicast_router);
BRPORT_ATTR_FLAG(multicast_fast_leave, BR_MULTICAST_FAST_LEAVE);
+BRPORT_ATTR_FLAG(multicast_to_unicast, BR_MULTICAST_TO_UCAST);
#endif
static const struct brport_attribute *brport_attrs[] = {
@@ -213,6 +214,7 @@ static const struct brport_attribute *br
#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
&brport_attr_multicast_router,
&brport_attr_multicast_fast_leave,
+ &brport_attr_multicast_to_unicast,
#endif
&brport_attr_isolated,
NULL