From 36fd2b63e3b4336744cf3f6a6c9543ecbec334a7 Mon Sep 17 00:00:00 2001 From: stephen hemminger Date: Mon, 4 Apr 2011 14:03:31 +0000 Subject: [PATCH] bridge: allow creating/deleting fdb entries via netlink Use RTM_NEWNEIGH and RTM_DELNEIGH to allow updating of entries in bridge forwarding table. This allows manipulating static entries which is not possible with existing tools. Example (using bridge extensions to iproute2) # br fdb add 00:02:03:04:05:06 dev eth0 Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- net/bridge/br_fdb.c | 139 ++++++++++++++++++++++++++++++++++++++++ net/bridge/br_netlink.c | 3 + net/bridge/br_private.h | 2 + 3 files changed, 144 insertions(+) diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c index 5e19e61396c3..498f47c1c453 100644 --- a/net/bridge/br_fdb.c +++ b/net/bridge/br_fdb.c @@ -555,3 +555,142 @@ skip: return skb->len; } + +/* Create new static fdb entry */ +static int fdb_add_entry(struct net_bridge_port *source, const __u8 *addr, + __u16 state) +{ + struct net_bridge *br = source->br; + struct hlist_head *head = &br->hash[br_mac_hash(addr)]; + struct net_bridge_fdb_entry *fdb; + + fdb = fdb_find(head, addr); + if (fdb) + return -EEXIST; + + fdb = fdb_create(head, source, addr); + if (!fdb) + return -ENOMEM; + + if (state & NUD_PERMANENT) + fdb->is_local = fdb->is_static = 1; + else if (state & NUD_NOARP) + fdb->is_static = 1; + return 0; +} + +/* Add new permanent fdb entry with RTM_NEWNEIGH */ +int br_fdb_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) +{ + struct net *net = sock_net(skb->sk); + struct ndmsg *ndm; + struct nlattr *tb[NDA_MAX+1]; + struct net_device *dev; + struct net_bridge_port *p; + const __u8 *addr; + int err; + + ASSERT_RTNL(); + err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, NULL); + if (err < 0) + return err; + + ndm = nlmsg_data(nlh); + if (ndm->ndm_ifindex == 0) { + pr_info("bridge: RTM_NEWNEIGH with invalid ifindex\n"); + return -EINVAL; + } + + dev = __dev_get_by_index(net, ndm->ndm_ifindex); + if (dev == NULL) { + pr_info("bridge: RTM_NEWNEIGH with unknown ifindex\n"); + return -ENODEV; + } + + if (!tb[NDA_LLADDR] || nla_len(tb[NDA_LLADDR]) != ETH_ALEN) { + pr_info("bridge: RTM_NEWNEIGH with invalid address\n"); + return -EINVAL; + } + + addr = nla_data(tb[NDA_LLADDR]); + if (!is_valid_ether_addr(addr)) { + pr_info("bridge: RTM_NEWNEIGH with invalid ether address\n"); + return -EINVAL; + } + + p = br_port_get_rtnl(dev); + if (p == NULL) { + pr_info("bridge: RTM_NEWNEIGH %s not a bridge port\n", + dev->name); + return -EINVAL; + } + + spin_lock_bh(&p->br->hash_lock); + err = fdb_add_entry(p, addr, ndm->ndm_state); + spin_unlock_bh(&p->br->hash_lock); + + return err; +} + +static int fdb_delete_by_addr(struct net_bridge_port *p, const u8 *addr) +{ + struct net_bridge *br = p->br; + struct hlist_head *head = &br->hash[br_mac_hash(addr)]; + struct net_bridge_fdb_entry *fdb; + + fdb = fdb_find(head, addr); + if (!fdb) + return -ENOENT; + + fdb_delete(fdb); + return 0; +} + +/* Remove neighbor entry with RTM_DELNEIGH */ +int br_fdb_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) +{ + struct net *net = sock_net(skb->sk); + struct ndmsg *ndm; + struct net_bridge_port *p; + struct nlattr *llattr; + const __u8 *addr; + struct net_device *dev; + int err; + + ASSERT_RTNL(); + if (nlmsg_len(nlh) < sizeof(*ndm)) + return -EINVAL; + + ndm = nlmsg_data(nlh); + if (ndm->ndm_ifindex == 0) { + pr_info("bridge: RTM_DELNEIGH with invalid ifindex\n"); + return -EINVAL; + } + + dev = __dev_get_by_index(net, ndm->ndm_ifindex); + if (dev == NULL) { + pr_info("bridge: RTM_DELNEIGH with unknown ifindex\n"); + return -ENODEV; + } + + llattr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_LLADDR); + if (llattr == NULL || nla_len(llattr) != ETH_ALEN) { + pr_info("bridge: RTM_DELNEIGH with invalid address\n"); + return -EINVAL; + } + + addr = nla_data(llattr); + + p = br_port_get_rtnl(dev); + if (p == NULL) { + pr_info("bridge: RTM_DELNEIGH %s not a bridge port\n", + dev->name); + return -EINVAL; + } + + spin_lock_bh(&p->br->hash_lock); + err = fdb_delete_by_addr(p, addr); + spin_unlock_bh(&p->br->hash_lock); + + return err; +} diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c index cedcafd115f3..fb7d5a7478fe 100644 --- a/net/bridge/br_netlink.c +++ b/net/bridge/br_netlink.c @@ -196,6 +196,9 @@ int __init br_netlink_init(void) /* Only the first call to __rtnl_register can fail */ __rtnl_register(PF_BRIDGE, RTM_SETLINK, br_rtm_setlink, NULL); + + __rtnl_register(PF_BRIDGE, RTM_NEWNEIGH, br_fdb_add, NULL); + __rtnl_register(PF_BRIDGE, RTM_DELNEIGH, br_fdb_delete, NULL); __rtnl_register(PF_BRIDGE, RTM_GETNEIGH, NULL, br_fdb_dump); return 0; diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index 884d245a205a..4bbe0d14c9a2 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -355,6 +355,8 @@ extern void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source, const unsigned char *addr); extern int br_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb); +extern int br_fdb_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg); +extern int br_fdb_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg); /* br_forward.c */ extern void br_deliver(const struct net_bridge_port *to, -- 2.39.5