diff options
Diffstat (limited to 'net/bridge/br_mdb.c')
| -rw-r--r-- | net/bridge/br_mdb.c | 481 |
1 files changed, 481 insertions, 0 deletions
diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c new file mode 100644 index 000000000000..6f0a2eebcb27 --- /dev/null +++ b/net/bridge/br_mdb.c @@ -0,0 +1,481 @@ +#include <linux/err.h> +#include <linux/igmp.h> +#include <linux/kernel.h> +#include <linux/netdevice.h> +#include <linux/rculist.h> +#include <linux/skbuff.h> +#include <linux/if_ether.h> +#include <net/ip.h> +#include <net/netlink.h> +#if IS_ENABLED(CONFIG_IPV6) +#include <net/ipv6.h> +#endif + +#include "br_private.h" + +static int br_rports_fill_info(struct sk_buff *skb, struct netlink_callback *cb, + struct net_device *dev) +{ + struct net_bridge *br = netdev_priv(dev); + struct net_bridge_port *p; + struct hlist_node *n; + struct nlattr *nest; + + if (!br->multicast_router || hlist_empty(&br->router_list)) + return 0; + + nest = nla_nest_start(skb, MDBA_ROUTER); + if (nest == NULL) + return -EMSGSIZE; + + hlist_for_each_entry_rcu(p, n, &br->router_list, rlist) { + if (p && nla_put_u32(skb, MDBA_ROUTER_PORT, p->dev->ifindex)) + goto fail; + } + + nla_nest_end(skb, nest); + return 0; +fail: + nla_nest_cancel(skb, nest); + return -EMSGSIZE; +} + +static int br_mdb_fill_info(struct sk_buff *skb, struct netlink_callback *cb, + struct net_device *dev) +{ + struct net_bridge *br = netdev_priv(dev); + struct net_bridge_mdb_htable *mdb; + struct nlattr *nest, *nest2; + int i, err = 0; + int idx = 0, s_idx = cb->args[1]; + + if (br->multicast_disabled) + return 0; + + mdb = rcu_dereference(br->mdb); + if (!mdb) + return 0; + + nest = nla_nest_start(skb, MDBA_MDB); + if (nest == NULL) + return -EMSGSIZE; + + for (i = 0; i < mdb->max; i++) { + struct hlist_node *h; + struct net_bridge_mdb_entry *mp; + struct net_bridge_port_group *p, **pp; + struct net_bridge_port *port; + + hlist_for_each_entry_rcu(mp, h, &mdb->mhash[i], hlist[mdb->ver]) { + if (idx < s_idx) + goto skip; + + nest2 = nla_nest_start(skb, MDBA_MDB_ENTRY); + if (nest2 == NULL) { + err = -EMSGSIZE; + goto out; + } + + for (pp = &mp->ports; + (p = rcu_dereference(*pp)) != NULL; + pp = &p->next) { + port = p->port; + if (port) { + struct br_mdb_entry e; + e.ifindex = port->dev->ifindex; + e.addr.u.ip4 = p->addr.u.ip4; +#if IS_ENABLED(CONFIG_IPV6) + e.addr.u.ip6 = p->addr.u.ip6; +#endif + e.addr.proto = p->addr.proto; + if (nla_put(skb, MDBA_MDB_ENTRY_INFO, sizeof(e), &e)) { + nla_nest_cancel(skb, nest2); + err = -EMSGSIZE; + goto out; + } + } + } + nla_nest_end(skb, nest2); + skip: + idx++; + } + } + +out: + cb->args[1] = idx; + nla_nest_end(skb, nest); + return err; +} + +static int br_mdb_dump(struct sk_buff *skb, struct netlink_callback *cb) +{ + struct net_device *dev; + struct net *net = sock_net(skb->sk); + struct nlmsghdr *nlh = NULL; + int idx = 0, s_idx; + + s_idx = cb->args[0]; + + rcu_read_lock(); + + /* In theory this could be wrapped to 0... */ + cb->seq = net->dev_base_seq + br_mdb_rehash_seq; + + for_each_netdev_rcu(net, dev) { + if (dev->priv_flags & IFF_EBRIDGE) { + struct br_port_msg *bpm; + + if (idx < s_idx) + goto skip; + + nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, + cb->nlh->nlmsg_seq, RTM_GETMDB, + sizeof(*bpm), NLM_F_MULTI); + if (nlh == NULL) + break; + + bpm = nlmsg_data(nlh); + bpm->ifindex = dev->ifindex; + if (br_mdb_fill_info(skb, cb, dev) < 0) + goto out; + if (br_rports_fill_info(skb, cb, dev) < 0) + goto out; + + cb->args[1] = 0; + nlmsg_end(skb, nlh); + skip: + idx++; + } + } + +out: + if (nlh) + nlmsg_end(skb, nlh); + rcu_read_unlock(); + cb->args[0] = idx; + return skb->len; +} + +static int nlmsg_populate_mdb_fill(struct sk_buff *skb, + struct net_device *dev, + struct br_mdb_entry *entry, u32 pid, + u32 seq, int type, unsigned int flags) +{ + struct nlmsghdr *nlh; + struct br_port_msg *bpm; + struct nlattr *nest, *nest2; + + nlh = nlmsg_put(skb, pid, seq, type, sizeof(*bpm), NLM_F_MULTI); + if (!nlh) + return -EMSGSIZE; + + bpm = nlmsg_data(nlh); + bpm->family = AF_BRIDGE; + bpm->ifindex = dev->ifindex; + nest = nla_nest_start(skb, MDBA_MDB); + if (nest == NULL) + goto cancel; + nest2 = nla_nest_start(skb, MDBA_MDB_ENTRY); + if (nest2 == NULL) + goto end; + + if (nla_put(skb, MDBA_MDB_ENTRY_INFO, sizeof(*entry), entry)) + goto end; + + nla_nest_end(skb, nest2); + nla_nest_end(skb, nest); + return nlmsg_end(skb, nlh); + +end: + nla_nest_end(skb, nest); +cancel: + nlmsg_cancel(skb, nlh); + return -EMSGSIZE; +} + +static inline size_t rtnl_mdb_nlmsg_size(void) +{ + return NLMSG_ALIGN(sizeof(struct br_port_msg)) + + nla_total_size(sizeof(struct br_mdb_entry)); +} + +static void __br_mdb_notify(struct net_device *dev, struct br_mdb_entry *entry, + int type) +{ + struct net *net = dev_net(dev); + struct sk_buff *skb; + int err = -ENOBUFS; + + skb = nlmsg_new(rtnl_mdb_nlmsg_size(), GFP_ATOMIC); + if (!skb) + goto errout; + + err = nlmsg_populate_mdb_fill(skb, dev, entry, 0, 0, type, NTF_SELF); + if (err < 0) { + kfree_skb(skb); + goto errout; + } + + rtnl_notify(skb, net, 0, RTNLGRP_MDB, NULL, GFP_ATOMIC); + return; +errout: + rtnl_set_sk_err(net, RTNLGRP_MDB, err); +} + +void br_mdb_notify(struct net_device *dev, struct net_bridge_port *port, + struct br_ip *group, int type) +{ + struct br_mdb_entry entry; + + entry.ifindex = port->dev->ifindex; + entry.addr.proto = group->proto; + entry.addr.u.ip4 = group->u.ip4; +#if IS_ENABLED(CONFIG_IPV6) + entry.addr.u.ip6 = group->u.ip6; +#endif + __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); +} |