bridge br_multicast: Make functions less ipv4 dependent.

Introduce struct br_ip{} to store ip address and protocol
and make functions more generic so that we can support
both IPv4 and IPv6 with less pain.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

2 files changed, 151 insertions, 58 deletions

diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 81bfdfe14ce5..64a3e4f74348 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -27,48 +27,86 @@
 
 #include "br_private.h"
 
-static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb, __be32 ip)
+static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
+{
+        if (a->proto != b->proto)
+                return 0;
+        switch (a->proto) {
+        case htons(ETH_P_IP):
+                return a->u.ip4 == b->u.ip4;
+        }
+        return 0;
+}
+
+static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip)
 {
         return jhash_1word(mdb->secret, (__force u32)ip) & (mdb->max - 1);
 }
 
+static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
+                             struct br_ip *ip)
+{
+        switch (ip->proto) {
+        case htons(ETH_P_IP):
+                return __br_ip4_hash(mdb, ip->u.ip4);
+        }
+        return 0;
+}
+
 static struct net_bridge_mdb_entry *__br_mdb_ip_get(
-        struct net_bridge_mdb_htable *mdb, __be32 dst, int hash)
+        struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
 {
         struct net_bridge_mdb_entry *mp;
         struct hlist_node *p;
 
         hlist_for_each_entry_rcu(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
-                if (dst == mp->addr)
+                if (br_ip_equal(&mp->addr, dst))
                         return mp;
         }
 
         return NULL;
 }
 
-static struct net_bridge_mdb_entry *br_mdb_ip_get(
+static struct net_bridge_mdb_entry *br_mdb_ip4_get(
         struct net_bridge_mdb_htable *mdb, __be32 dst)
 {
-        if (!mdb)
-                return NULL;
+        struct br_ip br_dst;
+
+        br_dst.u.ip4 = dst;
+        br_dst.proto = htons(ETH_P_IP);
 
+        return __br_mdb_ip_get(mdb, &br_dst, __br_ip4_hash(mdb, dst));
+}
+
+static struct net_bridge_mdb_entry *br_mdb_ip_get(
+        struct net_bridge_mdb_htable *mdb, struct br_ip *dst)
+{
         return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
 }
 
 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
                                         struct sk_buff *skb)
 {
-        if (br->multicast_disabled)
+        struct net_bridge_mdb_htable *mdb = br->mdb;
+        struct br_ip ip;
+
+        if (!mdb || br->multicast_disabled)
+                return NULL;
+
+        if (BR_INPUT_SKB_CB(skb)->igmp)
                 return NULL;
 
+        ip.proto = skb->protocol;
+
         switch (skb->protocol) {
         case htons(ETH_P_IP):
-                if (BR_INPUT_SKB_CB(skb)->igmp)
-                        break;
-                return br_mdb_ip_get(br->mdb, ip_hdr(skb)->daddr);
+                ip.u.ip4 = ip_hdr(skb)->daddr;
+                break;
+        default:
+                return NULL;
         }
 
-        return NULL;
+        return br_mdb_ip_get(mdb, &ip);
 }
 
 static void br_mdb_free(struct rcu_head *head)
@@ -95,7 +133,7 @@ static int br_mdb_copy(struct net_bridge_mdb_htable *new,
         for (i = 0; i < old->max; i++)
                 hlist_for_each_entry(mp, p, &old->mhash[i], hlist[old->ver])
                         hlist_add_head(&mp->hlist[new->ver],
-                                       &new->mhash[br_ip_hash(new, mp->addr)]);
+                                       &new->mhash[br_ip_hash(new, &mp->addr)]);
 
         if (!elasticity)
                 return 0;
@@ -163,7 +201,7 @@ static void br_multicast_del_pg(struct net_bridge *br,
         struct net_bridge_port_group *p;
         struct net_bridge_port_group **pp;
 
-        mp = br_mdb_ip_get(mdb, pg->addr);
+        mp = br_mdb_ip_get(mdb, &pg->addr);
         if (WARN_ON(!mp))
                 return;
 
@@ -249,8 +287,8 @@ out:
         return 0;
 }
 
-static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
-                                                __be32 group)
+static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
+                                                    __be32 group)
 {
         struct sk_buff *skb;
         struct igmphdr *ih;
@@ -314,12 +352,22 @@ out:
         return skb;
 }
 
+static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
+                                                struct br_ip *addr)
+{
+        switch (addr->proto) {
+        case htons(ETH_P_IP):
+                return br_ip4_multicast_alloc_query(br, addr->u.ip4);
+        }
+        return NULL;
+}
+
 static void br_multicast_send_group_query(struct net_bridge_mdb_entry *mp)
 {
         struct net_bridge *br = mp->br;
         struct sk_buff *skb;
 
-        skb = br_multicast_alloc_query(br, mp->addr);
+        skb = br_multicast_alloc_query(br, &mp->addr);
         if (!skb)
                 goto timer;
 
@@ -353,7 +401,7 @@ static void br_multicast_send_port_group_query(struct net_bridge_port_group *pg)
         struct net_bridge *br = port->br;
         struct sk_buff *skb;
 
-        skb = br_multicast_alloc_query(br, pg->addr);
+        skb = br_multicast_alloc_query(br, &pg->addr);
         if (!skb)
                 goto timer;
 
@@ -383,8 +431,8 @@ out:
 }
 
 static struct net_bridge_mdb_entry *br_multicast_get_group(
-        struct net_bridge *br, struct net_bridge_port *port, __be32 group,
-        int hash)
+        struct net_bridge *br, struct net_bridge_port *port,
+        struct br_ip *group, int hash)
 {
         struct net_bridge_mdb_htable *mdb = br->mdb;
         struct net_bridge_mdb_entry *mp;
@@ -396,9 +444,8 @@ static struct net_bridge_mdb_entry *br_multicast_get_group(
 
         hlist_for_each_entry(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
                 count++;
-                if (unlikely(group == mp->addr)) {
+                if (unlikely(br_ip_equal(group, &mp->addr)))
                         return mp;
-                }
         }
 
         elasticity = 0;
@@ -463,7 +510,8 @@ err:
 }
 
 static struct net_bridge_mdb_entry *br_multicast_new_group(
-        struct net_bridge *br, struct net_bridge_port *port, __be32 group)
+        struct net_bridge *br, struct net_bridge_port *port,
+        struct br_ip *group)
 {
         struct net_bridge_mdb_htable *mdb = br->mdb;
         struct net_bridge_mdb_entry *mp;
@@ -496,7 +544,7 @@ rehash:
                 goto out;
 
         mp->br = br;
-        mp->addr = group;
+        mp->addr = *group;
         setup_timer(&mp->timer, br_multicast_group_expired,
                     (unsigned long)mp);
         setup_timer(&mp->query_timer, br_multicast_group_query_expired,
@@ -510,7 +558,8 @@ out:
 }
 
 static int br_multicast_add_group(struct net_bridge *br,
-                                  struct net_bridge_port *port, __be32 group)
+                                  struct net_bridge_port *port,
+                                  struct br_ip *group)
 {
         struct net_bridge_mdb_entry *mp;
         struct net_bridge_port_group *p;
@@ -518,9 +567,6 @@ static int br_multicast_add_group(struct net_bridge *br,
         unsigned long now = jiffies;
         int err;
 
-        if (ipv4_is_local_multicast(group))
-                return 0;
-
         spin_lock(&br->multicast_lock);
         if (!netif_running(br->dev) ||
             (port && port->state == BR_STATE_DISABLED))
@@ -549,7 +595,7 @@ static int br_multicast_add_group(struct net_bridge *br,
         if (unlikely(!p))
                 goto err;
 
-        p->addr = group;
+        p->addr = *group;
         p->port = port;
         p->next = *pp;
         hlist_add_head(&p->mglist, &port->mglist);
@@ -570,6 +616,21 @@ err:
         return err;
 }
 
+static int br_ip4_multicast_add_group(struct net_bridge *br,
+                                      struct net_bridge_port *port,
+                                      __be32 group)
+{
+        struct br_ip br_group;
+
+        if (ipv4_is_local_multicast(group))
+                return 0;
+
+        br_group.u.ip4 = group;
+        br_group.proto = htons(ETH_P_IP);
+
+        return br_multicast_add_group(br, port, &br_group);
+}
+
 static void br_multicast_router_expired(unsigned long data)
 {
         struct net_bridge_port *port = (void *)data;
@@ -591,19 +652,15 @@ static void br_multicast_local_router_expired(unsigned long data)
 {
 }
 
-static void br_multicast_send_query(struct net_bridge *br,
-                                    struct net_bridge_port *port, u32 sent)
+static void __br_multicast_send_query(struct net_bridge *br,
+                                      struct net_bridge_port *port,
+                                      struct br_ip *ip)
 {
-        unsigned long time;
         struct sk_buff *skb;
 
-        if (!netif_running(br->dev) || br->multicast_disabled ||
-            timer_pending(&br->multicast_querier_timer))
-                return;
-
-        skb = br_multicast_alloc_query(br, 0);
+        skb = br_multicast_alloc_query(br, ip);
         if (!skb)
-                goto timer;
+                return;
 
         if (port) {
                 __skb_push(skb, sizeof(struct ethhdr));
@@ -612,8 +669,23 @@ static void br_multicast_send_query(struct net_bridge *br,
                         dev_queue_xmit);
         } else
                 netif_rx(skb);
+}
+
+static void br_multicast_send_query(struct net_bridge *br,
+                                    struct net_bridge_port *port, u32 sent)
+{
+        unsigned long time;
+        struct br_ip br_group;
+
+        if (!netif_running(br->dev) || br->multicast_disabled ||
+            timer_pending(&br->multicast_querier_timer))
+                return;
+
+        br_group.u.ip4 = 0;
+        br_group.proto = htons(ETH_P_IP);
+
+        __br_multicast_send_query(br, port, &br_group);
 
-timer:
         time = jiffies;
         time += sent < br->multicast_startup_query_count ?
                 br->multicast_startup_query_interval :
@@ -698,9 +770,9 @@ void br_multicast_disable_port(struct net_bridge_port *port)
         spin_unlock(&br->multicast_lock);
 }
 
-static int br_multicast_igmp3_report(struct net_bridge *br,
-                                     struct net_bridge_port *port,
-                                     struct sk_buff *skb)
+static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
+                                         struct net_bridge_port *port,
+                                         struct sk_buff *skb)
 {
         struct igmpv3_report *ih;
         struct igmpv3_grec *grec;
@@ -745,7 +817,7 @@ static int br_multicast_igmp3_report(struct net_bridge *br,
                         continue;
                 }
 
-                err = br_multicast_add_group(br, port, group);
+                err = br_ip4_multicast_add_group(br, port, group);
                 if (err)
                         break;
         }
@@ -800,7 +872,7 @@ timer:
 
 static void br_multicast_query_received(struct net_bridge *br,
                                         struct net_bridge_port *port,
-                                        __be32 saddr)
+                                        int saddr)
 {
         if (saddr)
                 mod_timer(&br->multicast_querier_timer,
@@ -811,9 +883,9 @@ static void br_multicast_query_received(struct net_bridge *br,
         br_multicast_mark_router(br, port);
 }
 
-static int br_multicast_query(struct net_bridge *br,
-                              struct net_bridge_port *port,
-                              struct sk_buff *skb)
+static int br_ip4_multicast_query(struct net_bridge *br,
+                                  struct net_bridge_port *port,
+                                  struct sk_buff *skb)
 {
         struct iphdr *iph = ip_hdr(skb);
         struct igmphdr *ih = igmp_hdr(skb);
@@ -831,7 +903,7 @@ static int br_multicast_query(struct net_bridge *br,
             (port && port->state == BR_STATE_DISABLED))
                 goto out;
 
-        br_multicast_query_received(br, port, iph->saddr);
+        br_multicast_query_received(br, port, !!iph->saddr);
 
         group = ih->group;
 
@@ -859,7 +931,7 @@ static int br_multicast_query(struct net_bridge *br,
         if (!group)
                 goto out;
 
-        mp = br_mdb_ip_get(br->mdb, group);
+        mp = br_mdb_ip4_get(br->mdb, group);
         if (!mp)
                 goto out;
 
@@ -885,7 +957,7 @@ out:
 
 static void br_multicast_leave_group(struct net_bridge *br,
                                      struct net_bridge_port *port,
-                                     __be32 group)
+                                     struct br_ip *group)
 {
         struct net_bridge_mdb_htable *mdb;
         struct net_bridge_mdb_entry *mp;
@@ -893,9 +965,6 @@ static void br_multicast_leave_group(struct net_bridge *br,
         unsigned long now;
         unsigned long time;
 
-        if (ipv4_is_local_multicast(group))
-                return;
-
         spin_lock(&br->multicast_lock);
         if (!netif_running(br->dev) ||
             (port && port->state == BR_STATE_DISABLED) ||
@@ -946,6 +1015,22 @@ out:
         spin_unlock(&br->multicast_lock);
 }
 
+static void br_ip4_multicast_leave_group(struct net_bridge *br,
+                                         struct net_bridge_port *port,
+                                         __be32 group)
+{
+        struct br_ip br_group;
+
+        if (ipv4_is_local_multicast(group))
+                return;
+
+        br_group.u.ip4 = group;
+        br_group.proto = htons(ETH_P_IP);
+
+        br_multicast_leave_group(br, port, &br_group);
+}
+
+
 static int br_multicast_ipv4_rcv(struct net_bridge *br,
                                  struct net_bridge_port *port,
                                  struct sk_buff *skb)
@@ -1023,16 +1108,16 @@ static int br_multicast_ipv4_rcv(struct net_bridge *br,
         case IGMP_HOST_MEMBERSHIP_REPORT:
         case IGMPV2_HOST_MEMBERSHIP_REPORT:
                 BR_INPUT_SKB_CB(skb2)->mrouters_only = 1;
-                err = br_multicast_add_group(br, port, ih->group);
+                err = br_ip4_multicast_add_group(br, port, ih->group);
                 break;
         case IGMPV3_HOST_MEMBERSHIP_REPORT:
-                err = br_multicast_igmp3_report(br, port, skb2);
+                err = br_ip4_multicast_igmp3_report(br, port, skb2);
                 break;
         case IGMP_HOST_MEMBERSHIP_QUERY:
-                err = br_multicast_query(br, port, skb2);
+                err = br_ip4_multicast_query(br, port, skb2);
                 break;
         case IGMP_HOST_LEAVE_MESSAGE:
-                br_multicast_leave_group(br, port, ih->group);
+                br_ip4_multicast_leave_group(br, port, ih->group);
                 break;
         }
 
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index 63181e4a2a67..45d11e49fbbb 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -45,6 +45,14 @@ struct mac_addr
         unsigned char   addr[6];
 };
 
+struct br_ip
+{
+        union {
+                __be32  ip4;
+        } u;
+        __be16          proto;
+};
+
 struct net_bridge_fdb_entry
 {
         struct hlist_node               hlist;
@@ -64,7 +72,7 @@ struct net_bridge_port_group {
         struct rcu_head                 rcu;
         struct timer_list               timer;
         struct timer_list               query_timer;
-        __be32                          addr;
+        struct br_ip                    addr;
         u32                             queries_sent;
 };
 
@@ -77,7 +85,7 @@ struct net_bridge_mdb_entry
         struct rcu_head                 rcu;
         struct timer_list               timer;
         struct timer_list               query_timer;
-        __be32                          addr;
+        struct br_ip                    addr;
         u32                             queries_sent;
 };