From cfd567543590f71ca0af397437e2554f9756d750 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Tue, 11 Dec 2012 22:23:08 +0000 Subject: [PATCH] bridge: add support of adding and deleting mdb entries This patch implents adding/deleting mdb entries via netlink. Currently all entries are temp, we probably need a flag to distinguish permanent entries too. Cc: Herbert Xu Cc: Stephen Hemminger Cc: "David S. Miller" Cc: Thomas Graf Signed-off-by: Cong Wang Signed-off-by: David S. Miller --- include/uapi/linux/if_bridge.h | 8 ++ net/bridge/br_mdb.c | 240 +++++++++++++++++++++++++++++++++ net/bridge/br_multicast.c | 55 ++++---- net/bridge/br_private.h | 23 ++++ 4 files changed, 297 insertions(+), 29 deletions(-) diff --git a/include/uapi/linux/if_bridge.h b/include/uapi/linux/if_bridge.h index 9a0f6ff0d7e7..afbb18a0227c 100644 --- a/include/uapi/linux/if_bridge.h +++ b/include/uapi/linux/if_bridge.h @@ -157,6 +157,7 @@ enum { #define MDBA_ROUTER_MAX (__MDBA_ROUTER_MAX - 1) struct br_port_msg { + __u8 family; __u32 ifindex; }; @@ -171,4 +172,11 @@ struct br_mdb_entry { } addr; }; +enum { + MDBA_SET_ENTRY_UNSPEC, + MDBA_SET_ENTRY, + __MDBA_SET_ENTRY_MAX, +}; +#define MDBA_SET_ENTRY_MAX (__MDBA_SET_ENTRY_MAX - 1) + #endif /* _UAPI_LINUX_IF_BRIDGE_H */ diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c index a8cfbf5f3c68..6f0a2eebcb27 100644 --- a/net/bridge/br_mdb.c +++ b/net/bridge/br_mdb.c @@ -4,6 +4,7 @@ #include #include #include +#include #include #include #if IS_ENABLED(CONFIG_IPV6) @@ -235,7 +236,246 @@ void br_mdb_notify(struct net_device *dev, struct net_bridge_port *port, __br_mdb_notify(dev, &entry, type); } +static bool is_valid_mdb_entry(struct br_mdb_entry *entry) +{ + if (entry->ifindex == 0) + return false; + + if (entry->addr.proto == htons(ETH_P_IP)) { + if (!ipv4_is_multicast(entry->addr.u.ip4)) + return false; + if (ipv4_is_local_multicast(entry->addr.u.ip4)) + return false; +#if IS_ENABLED(CONFIG_IPV6) + } else if (entry->addr.proto == htons(ETH_P_IPV6)) { + if (!ipv6_is_transient_multicast(&entry->addr.u.ip6)) + return false; +#endif + } else + return false; + + return true; +} + +static int br_mdb_parse(struct sk_buff *skb, struct nlmsghdr *nlh, + struct net_device **pdev, struct br_mdb_entry **pentry) +{ + struct net *net = sock_net(skb->sk); + struct br_mdb_entry *entry; + struct br_port_msg *bpm; + struct nlattr *tb[MDBA_SET_ENTRY_MAX+1]; + struct net_device *dev; + int err; + + if (!capable(CAP_NET_ADMIN)) + return -EPERM; + + err = nlmsg_parse(nlh, sizeof(*bpm), tb, MDBA_SET_ENTRY, NULL); + if (err < 0) + return err; + + bpm = nlmsg_data(nlh); + if (bpm->ifindex == 0) { + pr_info("PF_BRIDGE: br_mdb_parse() with invalid ifindex\n"); + return -EINVAL; + } + + dev = __dev_get_by_index(net, bpm->ifindex); + if (dev == NULL) { + pr_info("PF_BRIDGE: br_mdb_parse() with unknown ifindex\n"); + return -ENODEV; + } + + if (!(dev->priv_flags & IFF_EBRIDGE)) { + pr_info("PF_BRIDGE: br_mdb_parse() with non-bridge\n"); + return -EOPNOTSUPP; + } + + *pdev = dev; + + if (!tb[MDBA_SET_ENTRY] || + nla_len(tb[MDBA_SET_ENTRY]) != sizeof(struct br_mdb_entry)) { + pr_info("PF_BRIDGE: br_mdb_parse() with invalid attr\n"); + return -EINVAL; + } + + entry = nla_data(tb[MDBA_SET_ENTRY]); + if (!is_valid_mdb_entry(entry)) { + pr_info("PF_BRIDGE: br_mdb_parse() with invalid entry\n"); + return -EINVAL; + } + + *pentry = entry; + return 0; +} + +static int br_mdb_add_group(struct net_bridge *br, struct net_bridge_port *port, + struct br_ip *group) +{ + struct net_bridge_mdb_entry *mp; + struct net_bridge_port_group *p; + struct net_bridge_port_group __rcu **pp; + struct net_bridge_mdb_htable *mdb; + int err; + + mdb = mlock_dereference(br->mdb, br); + mp = br_mdb_ip_get(mdb, group); + if (!mp) { + mp = br_multicast_new_group(br, port, group); + err = PTR_ERR(mp); + if (IS_ERR(mp)) + return err; + } + + for (pp = &mp->ports; + (p = mlock_dereference(*pp, br)) != NULL; + pp = &p->next) { + if (p->port == port) + return -EEXIST; + if ((unsigned long)p->port < (unsigned long)port) + break; + } + + p = br_multicast_new_port_group(port, group, *pp); + if (unlikely(!p)) + return -ENOMEM; + rcu_assign_pointer(*pp, p); + + br_mdb_notify(br->dev, port, group, RTM_NEWMDB); + return 0; +} + +static int __br_mdb_add(struct net *net, struct net_bridge *br, + struct br_mdb_entry *entry) +{ + struct br_ip ip; + struct net_device *dev; + struct net_bridge_port *p; + int ret; + + if (!netif_running(br->dev) || br->multicast_disabled) + return -EINVAL; + + dev = __dev_get_by_index(net, entry->ifindex); + if (!dev) + return -ENODEV; + + p = br_port_get_rtnl(dev); + if (!p || p->br != br || p->state == BR_STATE_DISABLED) + return -EINVAL; + + ip.proto = entry->addr.proto; + if (ip.proto == htons(ETH_P_IP)) + ip.u.ip4 = entry->addr.u.ip4; +#if IS_ENABLED(CONFIG_IPV6) + else + ip.u.ip6 = entry->addr.u.ip6; +#endif + + spin_lock_bh(&br->multicast_lock); + ret = br_mdb_add_group(br, p, &ip); + spin_unlock_bh(&br->multicast_lock); + return ret; +} + +static int br_mdb_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) +{ + struct net *net = sock_net(skb->sk); + struct br_mdb_entry *entry; + struct net_device *dev; + struct net_bridge *br; + int err; + + err = br_mdb_parse(skb, nlh, &dev, &entry); + if (err < 0) + return err; + + br = netdev_priv(dev); + + err = __br_mdb_add(net, br, entry); + if (!err) + __br_mdb_notify(dev, entry, RTM_NEWMDB); + return err; +} + +static int __br_mdb_del(struct net_bridge *br, struct br_mdb_entry *entry) +{ + struct net_bridge_mdb_htable *mdb; + struct net_bridge_mdb_entry *mp; + struct net_bridge_port_group *p; + struct net_bridge_port_group __rcu **pp; + struct br_ip ip; + int err = -EINVAL; + + if (!netif_running(br->dev) || br->multicast_disabled) + return -EINVAL; + + if (timer_pending(&br->multicast_querier_timer)) + return -EBUSY; + + ip.proto = entry->addr.proto; + if (ip.proto == htons(ETH_P_IP)) + ip.u.ip4 = entry->addr.u.ip4; +#if IS_ENABLED(CONFIG_IPV6) + else + ip.u.ip6 = entry->addr.u.ip6; +#endif + + spin_lock_bh(&br->multicast_lock); + mdb = mlock_dereference(br->mdb, br); + + mp = br_mdb_ip_get(mdb, &ip); + if (!mp) + goto unlock; + + for (pp = &mp->ports; + (p = mlock_dereference(*pp, br)) != NULL; + pp = &p->next) { + if (!p->port || p->port->dev->ifindex != entry->ifindex) + continue; + + if (p->port->state == BR_STATE_DISABLED) + goto unlock; + + rcu_assign_pointer(*pp, p->next); + hlist_del_init(&p->mglist); + del_timer(&p->timer); + call_rcu_bh(&p->rcu, br_multicast_free_pg); + err = 0; + + if (!mp->ports && !mp->mglist && + netif_running(br->dev)) + mod_timer(&mp->timer, jiffies); + break; + } + +unlock: + spin_unlock_bh(&br->multicast_lock); + return err; +} + +static int br_mdb_del(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) +{ + struct net_device *dev; + struct br_mdb_entry *entry; + struct net_bridge *br; + int err; + + err = br_mdb_parse(skb, nlh, &dev, &entry); + if (err < 0) + return err; + + br = netdev_priv(dev); + + err = __br_mdb_del(br, entry); + if (!err) + __br_mdb_notify(dev, entry, RTM_DELMDB); + return err; +} + void br_mdb_init(void) { rtnl_register(PF_BRIDGE, RTM_GETMDB, NULL, br_mdb_dump, NULL); + rtnl_register(PF_BRIDGE, RTM_NEWMDB, br_mdb_add, NULL, NULL); + rtnl_register(PF_BRIDGE, RTM_DELMDB, br_mdb_del, NULL, NULL); } diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index d929586ce39e..977c3ee02e65 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -27,27 +27,14 @@ #if IS_ENABLED(CONFIG_IPV6) #include #include -#include #include #endif #include "br_private.h" -#define mlock_dereference(X, br) \ - rcu_dereference_protected(X, lockdep_is_held(&br->multicast_lock)) - static void br_multicast_start_querier(struct net_bridge *br); unsigned int br_mdb_rehash_seq; -#if IS_ENABLED(CONFIG_IPV6) -static inline int ipv6_is_transient_multicast(const struct in6_addr *addr) -{ - if (ipv6_addr_is_multicast(addr) && IPV6_ADDR_MC_FLAG_TRANSIENT(addr)) - return 1; - return 0; -} -#endif - static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b) { if (a->proto != b->proto) @@ -104,8 +91,8 @@ static struct net_bridge_mdb_entry *__br_mdb_ip_get( return NULL; } -static struct net_bridge_mdb_entry *br_mdb_ip_get( - struct net_bridge_mdb_htable *mdb, struct br_ip *dst) +struct net_bridge_mdb_entry *br_mdb_ip_get(struct net_bridge_mdb_htable *mdb, + struct br_ip *dst) { if (!mdb) return NULL; @@ -208,7 +195,7 @@ static int br_mdb_copy(struct net_bridge_mdb_htable *new, return maxlen > elasticity ? -EINVAL : 0; } -static void br_multicast_free_pg(struct rcu_head *head) +void br_multicast_free_pg(struct rcu_head *head) { struct net_bridge_port_group *p = container_of(head, struct net_bridge_port_group, rcu); @@ -584,9 +571,8 @@ err: return mp; } -static struct net_bridge_mdb_entry *br_multicast_new_group( - struct net_bridge *br, struct net_bridge_port *port, - struct br_ip *group) +struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br, + struct net_bridge_port *port, struct br_ip *group) { struct net_bridge_mdb_htable *mdb; struct net_bridge_mdb_entry *mp; @@ -633,6 +619,26 @@ out: return mp; } +struct net_bridge_port_group *br_multicast_new_port_group( + struct net_bridge_port *port, + struct br_ip *group, + struct net_bridge_port_group *next) +{ + struct net_bridge_port_group *p; + + p = kzalloc(sizeof(*p), GFP_ATOMIC); + if (unlikely(!p)) + return NULL; + + p->addr = *group; + p->port = port; + p->next = next; + hlist_add_head(&p->mglist, &port->mglist); + setup_timer(&p->timer, br_multicast_port_group_expired, + (unsigned long)p); + return p; +} + static int br_multicast_add_group(struct net_bridge *br, struct net_bridge_port *port, struct br_ip *group) @@ -668,18 +674,9 @@ static int br_multicast_add_group(struct net_bridge *br, break; } - p = kzalloc(sizeof(*p), GFP_ATOMIC); - err = -ENOMEM; + p = br_multicast_new_port_group(port, group, *pp); if (unlikely(!p)) goto err; - - p->addr = *group; - p->port = port; - p->next = *pp; - hlist_add_head(&p->mglist, &port->mglist); - setup_timer(&p->timer, br_multicast_port_group_expired, - (unsigned long)p); - rcu_assign_pointer(*pp, p); br_mdb_notify(br->dev, port, group, RTM_NEWMDB); diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index 2807c7680c38..f21a739a6186 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -434,10 +434,33 @@ extern int br_multicast_set_port_router(struct net_bridge_port *p, extern int br_multicast_toggle(struct net_bridge *br, unsigned long val); extern int br_multicast_set_querier(struct net_bridge *br, unsigned long val); extern int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val); +extern struct net_bridge_mdb_entry *br_mdb_ip_get( + struct net_bridge_mdb_htable *mdb, + struct br_ip *dst); +extern struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br, + struct net_bridge_port *port, struct br_ip *group); +extern void br_multicast_free_pg(struct rcu_head *head); +extern struct net_bridge_port_group *br_multicast_new_port_group( + struct net_bridge_port *port, + struct br_ip *group, + struct net_bridge_port_group *next); extern void br_mdb_init(void); extern void br_mdb_notify(struct net_device *dev, struct net_bridge_port *port, struct br_ip *group, int type); +#define mlock_dereference(X, br) \ + rcu_dereference_protected(X, lockdep_is_held(&br->multicast_lock)) + +#if IS_ENABLED(CONFIG_IPV6) +#include +static inline int ipv6_is_transient_multicast(const struct in6_addr *addr) +{ + if (ipv6_addr_is_multicast(addr) && IPV6_ADDR_MC_FLAG_TRANSIENT(addr)) + return 1; + return 0; +} +#endif + static inline bool br_multicast_is_router(struct net_bridge *br) { return br->multicast_router == 2 || -- 2.20.1