From ee07c6e7a6f8a25c18f0a6b18152fbd7499245f6 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Fri, 7 Dec 2012 00:04:48 +0000 Subject: [PATCH] bridge: export multicast database via netlink V5: fix two bugs pointed out by Thomas remove seq check for now, mark it as TODO V4: remove some useless #include some coding style fix V3: drop debugging printk's update selinux perm table as well V2: drop patch 1/2, export ifindex directly Redesign netlink attributes Improve netlink seq check Handle IPv6 addr as well This patch exports bridge multicast database via netlink message type RTM_GETMDB. Similar to fdb, but currently bridge-specific. We may need to support modify multicast database too (RTM_{ADD,DEL}MDB). (Thanks to Thomas for patient reviews) Cc: Herbert Xu Cc: Stephen Hemminger Cc: "David S. Miller" Cc: Thomas Graf Cc: Jesper Dangaard Brouer Signed-off-by: Cong Wang Acked-by: Thomas Graf Signed-off-by: David S. Miller --- include/uapi/linux/if_bridge.h | 55 +++++++++++ include/uapi/linux/rtnetlink.h | 3 + net/bridge/Makefile | 2 +- net/bridge/br_mdb.c | 163 +++++++++++++++++++++++++++++++++ net/bridge/br_multicast.c | 1 + net/bridge/br_private.h | 1 + security/selinux/nlmsgtab.c | 1 + 7 files changed, 225 insertions(+), 1 deletion(-) create mode 100644 net/bridge/br_mdb.c diff --git a/include/uapi/linux/if_bridge.h b/include/uapi/linux/if_bridge.h index b3885791e11..9a0f6ff0d7e 100644 --- a/include/uapi/linux/if_bridge.h +++ b/include/uapi/linux/if_bridge.h @@ -116,4 +116,59 @@ enum { __IFLA_BRIDGE_MAX, }; #define IFLA_BRIDGE_MAX (__IFLA_BRIDGE_MAX - 1) + +/* Bridge multicast database attributes + * [MDBA_MDB] = { + * [MDBA_MDB_ENTRY] = { + * [MDBA_MDB_ENTRY_INFO] + * } + * } + * [MDBA_ROUTER] = { + * [MDBA_ROUTER_PORT] + * } + */ +enum { + MDBA_UNSPEC, + MDBA_MDB, + MDBA_ROUTER, + __MDBA_MAX, +}; +#define MDBA_MAX (__MDBA_MAX - 1) + +enum { + MDBA_MDB_UNSPEC, + MDBA_MDB_ENTRY, + __MDBA_MDB_MAX, +}; +#define MDBA_MDB_MAX (__MDBA_MDB_MAX - 1) + +enum { + MDBA_MDB_ENTRY_UNSPEC, + MDBA_MDB_ENTRY_INFO, + __MDBA_MDB_ENTRY_MAX, +}; +#define MDBA_MDB_ENTRY_MAX (__MDBA_MDB_ENTRY_MAX - 1) + +enum { + MDBA_ROUTER_UNSPEC, + MDBA_ROUTER_PORT, + __MDBA_ROUTER_MAX, +}; +#define MDBA_ROUTER_MAX (__MDBA_ROUTER_MAX - 1) + +struct br_port_msg { + __u32 ifindex; +}; + +struct br_mdb_entry { + __u32 ifindex; + struct { + union { + __be32 ip4; + struct in6_addr ip6; + } u; + __be16 proto; + } addr; +}; + #endif /* _UAPI_LINUX_IF_BRIDGE_H */ diff --git a/include/uapi/linux/rtnetlink.h b/include/uapi/linux/rtnetlink.h index 33d29cea37e..354a1e7d32a 100644 --- a/include/uapi/linux/rtnetlink.h +++ b/include/uapi/linux/rtnetlink.h @@ -125,6 +125,9 @@ enum { RTM_GETNETCONF = 82, #define RTM_GETNETCONF RTM_GETNETCONF + RTM_GETMDB = 86, +#define RTM_GETMDB RTM_GETMDB + __RTM_MAX, #define RTM_MAX (((__RTM_MAX + 3) & ~3) - 1) }; diff --git a/net/bridge/Makefile b/net/bridge/Makefile index d0359ea8ee7..e859098f5ee 100644 --- a/net/bridge/Makefile +++ b/net/bridge/Makefile @@ -12,6 +12,6 @@ bridge-$(CONFIG_SYSFS) += br_sysfs_if.o br_sysfs_br.o bridge-$(CONFIG_BRIDGE_NETFILTER) += br_netfilter.o -bridge-$(CONFIG_BRIDGE_IGMP_SNOOPING) += br_multicast.o +bridge-$(CONFIG_BRIDGE_IGMP_SNOOPING) += br_multicast.o br_mdb.o obj-$(CONFIG_BRIDGE_NF_EBTABLES) += netfilter/ diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c new file mode 100644 index 00000000000..edc0d731f6b --- /dev/null +++ b/net/bridge/br_mdb.c @@ -0,0 +1,163 @@ +#include +#include +#include +#include +#include +#include +#include +#include +#if IS_ENABLED(CONFIG_IPV6) +#include +#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(); + + /* TODO: in case of rehashing, we need to check + * consistency for dumping. + */ + cb->seq = net->dev_base_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; +} + +void br_mdb_init(void) +{ + rtnl_register(PF_BRIDGE, RTM_GETMDB, NULL, br_mdb_dump, NULL); +} diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index a2a7a1a7908..68e375ac93b 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -1605,6 +1605,7 @@ void br_multicast_init(struct net_bridge *br) br_multicast_querier_expired, (unsigned long)br); setup_timer(&br->multicast_query_timer, br_multicast_query_expired, (unsigned long)br); + br_mdb_init(); } void br_multicast_open(struct net_bridge *br) diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index cd86222cf5e..ae0a6ec0a70 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -433,6 +433,7 @@ 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 void br_mdb_init(void); static inline bool br_multicast_is_router(struct net_bridge *br) { diff --git a/security/selinux/nlmsgtab.c b/security/selinux/nlmsgtab.c index d309e7f472d..163aaa77d5a 100644 --- a/security/selinux/nlmsgtab.c +++ b/security/selinux/nlmsgtab.c @@ -67,6 +67,7 @@ static struct nlmsg_perm nlmsg_route_perms[] = { RTM_GETADDRLABEL, NETLINK_ROUTE_SOCKET__NLMSG_READ }, { RTM_GETDCB, NETLINK_ROUTE_SOCKET__NLMSG_READ }, { RTM_SETDCB, NETLINK_ROUTE_SOCKET__NLMSG_WRITE }, + { RTM_GETMDB, NETLINK_ROUTE_SOCKET__NLMSG_READ }, }; static struct nlmsg_perm nlmsg_tcpdiag_perms[] =