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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /net/bridge/br_fdb.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--net/bridge/br_fdb.c1318
1 files changed, 1318 insertions, 0 deletions
diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
new file mode 100644
index 000000000..8a6470a21
--- /dev/null
+++ b/net/bridge/br_fdb.c
@@ -0,0 +1,1318 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Forwarding database
+ * Linux ethernet bridge
+ *
+ * Authors:
+ * Lennert Buytenhek <buytenh@gnu.org>
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/rculist.h>
+#include <linux/spinlock.h>
+#include <linux/times.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/jhash.h>
+#include <linux/random.h>
+#include <linux/slab.h>
+#include <linux/atomic.h>
+#include <asm/unaligned.h>
+#include <linux/if_vlan.h>
+#include <net/switchdev.h>
+#include <trace/events/bridge.h>
+#include "br_private.h"
+
+static const struct rhashtable_params br_fdb_rht_params = {
+ .head_offset = offsetof(struct net_bridge_fdb_entry, rhnode),
+ .key_offset = offsetof(struct net_bridge_fdb_entry, key),
+ .key_len = sizeof(struct net_bridge_fdb_key),
+ .automatic_shrinking = true,
+};
+
+static struct kmem_cache *br_fdb_cache __read_mostly;
+static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
+ const unsigned char *addr, u16 vid);
+static void fdb_notify(struct net_bridge *br,
+ const struct net_bridge_fdb_entry *, int, bool);
+
+int __init br_fdb_init(void)
+{
+ br_fdb_cache = kmem_cache_create("bridge_fdb_cache",
+ sizeof(struct net_bridge_fdb_entry),
+ 0,
+ SLAB_HWCACHE_ALIGN, NULL);
+ if (!br_fdb_cache)
+ return -ENOMEM;
+
+ return 0;
+}
+
+void br_fdb_fini(void)
+{
+ kmem_cache_destroy(br_fdb_cache);
+}
+
+int br_fdb_hash_init(struct net_bridge *br)
+{
+ return rhashtable_init(&br->fdb_hash_tbl, &br_fdb_rht_params);
+}
+
+void br_fdb_hash_fini(struct net_bridge *br)
+{
+ rhashtable_destroy(&br->fdb_hash_tbl);
+}
+
+/* if topology_changing then use forward_delay (default 15 sec)
+ * otherwise keep longer (default 5 minutes)
+ */
+static inline unsigned long hold_time(const struct net_bridge *br)
+{
+ return br->topology_change ? br->forward_delay : br->ageing_time;
+}
+
+static inline int has_expired(const struct net_bridge *br,
+ const struct net_bridge_fdb_entry *fdb)
+{
+ return !test_bit(BR_FDB_STATIC, &fdb->flags) &&
+ !test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags) &&
+ time_before_eq(fdb->updated + hold_time(br), jiffies);
+}
+
+static void fdb_rcu_free(struct rcu_head *head)
+{
+ struct net_bridge_fdb_entry *ent
+ = container_of(head, struct net_bridge_fdb_entry, rcu);
+ kmem_cache_free(br_fdb_cache, ent);
+}
+
+static struct net_bridge_fdb_entry *fdb_find_rcu(struct rhashtable *tbl,
+ const unsigned char *addr,
+ __u16 vid)
+{
+ struct net_bridge_fdb_key key;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ key.vlan_id = vid;
+ memcpy(key.addr.addr, addr, sizeof(key.addr.addr));
+
+ return rhashtable_lookup(tbl, &key, br_fdb_rht_params);
+}
+
+/* requires bridge hash_lock */
+static struct net_bridge_fdb_entry *br_fdb_find(struct net_bridge *br,
+ const unsigned char *addr,
+ __u16 vid)
+{
+ struct net_bridge_fdb_entry *fdb;
+
+ lockdep_assert_held_once(&br->hash_lock);
+
+ rcu_read_lock();
+ fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
+ rcu_read_unlock();
+
+ return fdb;
+}
+
+struct net_device *br_fdb_find_port(const struct net_device *br_dev,
+ const unsigned char *addr,
+ __u16 vid)
+{
+ struct net_bridge_fdb_entry *f;
+ struct net_device *dev = NULL;
+ struct net_bridge *br;
+
+ ASSERT_RTNL();
+
+ if (!netif_is_bridge_master(br_dev))
+ return NULL;
+
+ br = netdev_priv(br_dev);
+ rcu_read_lock();
+ f = br_fdb_find_rcu(br, addr, vid);
+ if (f && f->dst)
+ dev = f->dst->dev;
+ rcu_read_unlock();
+
+ return dev;
+}
+EXPORT_SYMBOL_GPL(br_fdb_find_port);
+
+struct net_bridge_fdb_entry *br_fdb_find_rcu(struct net_bridge *br,
+ const unsigned char *addr,
+ __u16 vid)
+{
+ return fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
+}
+
+/* When a static FDB entry is added, the mac address from the entry is
+ * added to the bridge private HW address list and all required ports
+ * are then updated with the new information.
+ * Called under RTNL.
+ */
+static void fdb_add_hw_addr(struct net_bridge *br, const unsigned char *addr)
+{
+ int err;
+ struct net_bridge_port *p;
+
+ ASSERT_RTNL();
+
+ list_for_each_entry(p, &br->port_list, list) {
+ if (!br_promisc_port(p)) {
+ err = dev_uc_add(p->dev, addr);
+ if (err)
+ goto undo;
+ }
+ }
+
+ return;
+undo:
+ list_for_each_entry_continue_reverse(p, &br->port_list, list) {
+ if (!br_promisc_port(p))
+ dev_uc_del(p->dev, addr);
+ }
+}
+
+/* When a static FDB entry is deleted, the HW address from that entry is
+ * also removed from the bridge private HW address list and updates all
+ * the ports with needed information.
+ * Called under RTNL.
+ */
+static void fdb_del_hw_addr(struct net_bridge *br, const unsigned char *addr)
+{
+ struct net_bridge_port *p;
+
+ ASSERT_RTNL();
+
+ list_for_each_entry(p, &br->port_list, list) {
+ if (!br_promisc_port(p))
+ dev_uc_del(p->dev, addr);
+ }
+}
+
+static void fdb_delete(struct net_bridge *br, struct net_bridge_fdb_entry *f,
+ bool swdev_notify)
+{
+ trace_fdb_delete(br, f);
+
+ if (test_bit(BR_FDB_STATIC, &f->flags))
+ fdb_del_hw_addr(br, f->key.addr.addr);
+
+ hlist_del_init_rcu(&f->fdb_node);
+ rhashtable_remove_fast(&br->fdb_hash_tbl, &f->rhnode,
+ br_fdb_rht_params);
+ fdb_notify(br, f, RTM_DELNEIGH, swdev_notify);
+ call_rcu(&f->rcu, fdb_rcu_free);
+}
+
+/* Delete a local entry if no other port had the same address. */
+static void fdb_delete_local(struct net_bridge *br,
+ const struct net_bridge_port *p,
+ struct net_bridge_fdb_entry *f)
+{
+ const unsigned char *addr = f->key.addr.addr;
+ struct net_bridge_vlan_group *vg;
+ const struct net_bridge_vlan *v;
+ struct net_bridge_port *op;
+ u16 vid = f->key.vlan_id;
+
+ /* Maybe another port has same hw addr? */
+ list_for_each_entry(op, &br->port_list, list) {
+ vg = nbp_vlan_group(op);
+ if (op != p && ether_addr_equal(op->dev->dev_addr, addr) &&
+ (!vid || br_vlan_find(vg, vid))) {
+ f->dst = op;
+ clear_bit(BR_FDB_ADDED_BY_USER, &f->flags);
+ return;
+ }
+ }
+
+ vg = br_vlan_group(br);
+ v = br_vlan_find(vg, vid);
+ /* Maybe bridge device has same hw addr? */
+ if (p && ether_addr_equal(br->dev->dev_addr, addr) &&
+ (!vid || (v && br_vlan_should_use(v)))) {
+ f->dst = NULL;
+ clear_bit(BR_FDB_ADDED_BY_USER, &f->flags);
+ return;
+ }
+
+ fdb_delete(br, f, true);
+}
+
+void br_fdb_find_delete_local(struct net_bridge *br,
+ const struct net_bridge_port *p,
+ const unsigned char *addr, u16 vid)
+{
+ struct net_bridge_fdb_entry *f;
+
+ spin_lock_bh(&br->hash_lock);
+ f = br_fdb_find(br, addr, vid);
+ if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
+ !test_bit(BR_FDB_ADDED_BY_USER, &f->flags) && f->dst == p)
+ fdb_delete_local(br, p, f);
+ spin_unlock_bh(&br->hash_lock);
+}
+
+void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
+{
+ struct net_bridge_vlan_group *vg;
+ struct net_bridge_fdb_entry *f;
+ struct net_bridge *br = p->br;
+ struct net_bridge_vlan *v;
+
+ spin_lock_bh(&br->hash_lock);
+ vg = nbp_vlan_group(p);
+ hlist_for_each_entry(f, &br->fdb_list, fdb_node) {
+ if (f->dst == p && test_bit(BR_FDB_LOCAL, &f->flags) &&
+ !test_bit(BR_FDB_ADDED_BY_USER, &f->flags)) {
+ /* delete old one */
+ fdb_delete_local(br, p, f);
+
+ /* if this port has no vlan information
+ * configured, we can safely be done at
+ * this point.
+ */
+ if (!vg || !vg->num_vlans)
+ goto insert;
+ }
+ }
+
+insert:
+ /* insert new address, may fail if invalid address or dup. */
+ fdb_insert(br, p, newaddr, 0);
+
+ if (!vg || !vg->num_vlans)
+ goto done;
+
+ /* Now add entries for every VLAN configured on the port.
+ * This function runs under RTNL so the bitmap will not change
+ * from under us.
+ */
+ list_for_each_entry(v, &vg->vlan_list, vlist)
+ fdb_insert(br, p, newaddr, v->vid);
+
+done:
+ spin_unlock_bh(&br->hash_lock);
+}
+
+void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr)
+{
+ struct net_bridge_vlan_group *vg;
+ struct net_bridge_fdb_entry *f;
+ struct net_bridge_vlan *v;
+
+ spin_lock_bh(&br->hash_lock);
+
+ /* If old entry was unassociated with any port, then delete it. */
+ f = br_fdb_find(br, br->dev->dev_addr, 0);
+ if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
+ !f->dst && !test_bit(BR_FDB_ADDED_BY_USER, &f->flags))
+ fdb_delete_local(br, NULL, f);
+
+ fdb_insert(br, NULL, newaddr, 0);
+ vg = br_vlan_group(br);
+ if (!vg || !vg->num_vlans)
+ goto out;
+ /* Now remove and add entries for every VLAN configured on the
+ * bridge. This function runs under RTNL so the bitmap will not
+ * change from under us.
+ */
+ list_for_each_entry(v, &vg->vlan_list, vlist) {
+ if (!br_vlan_should_use(v))
+ continue;
+ f = br_fdb_find(br, br->dev->dev_addr, v->vid);
+ if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
+ !f->dst && !test_bit(BR_FDB_ADDED_BY_USER, &f->flags))
+ fdb_delete_local(br, NULL, f);
+ fdb_insert(br, NULL, newaddr, v->vid);
+ }
+out:
+ spin_unlock_bh(&br->hash_lock);
+}
+
+void br_fdb_cleanup(struct work_struct *work)
+{
+ struct net_bridge *br = container_of(work, struct net_bridge,
+ gc_work.work);
+ struct net_bridge_fdb_entry *f = NULL;
+ unsigned long delay = hold_time(br);
+ unsigned long work_delay = delay;
+ unsigned long now = jiffies;
+
+ /* this part is tricky, in order to avoid blocking learning and
+ * consequently forwarding, we rely on rcu to delete objects with
+ * delayed freeing allowing us to continue traversing
+ */
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
+ unsigned long this_timer = f->updated + delay;
+
+ if (test_bit(BR_FDB_STATIC, &f->flags) ||
+ test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags)) {
+ if (test_bit(BR_FDB_NOTIFY, &f->flags)) {
+ if (time_after(this_timer, now))
+ work_delay = min(work_delay,
+ this_timer - now);
+ else if (!test_and_set_bit(BR_FDB_NOTIFY_INACTIVE,
+ &f->flags))
+ fdb_notify(br, f, RTM_NEWNEIGH, false);
+ }
+ continue;
+ }
+
+ if (time_after(this_timer, now)) {
+ work_delay = min(work_delay, this_timer - now);
+ } else {
+ spin_lock_bh(&br->hash_lock);
+ if (!hlist_unhashed(&f->fdb_node))
+ fdb_delete(br, f, true);
+ spin_unlock_bh(&br->hash_lock);
+ }
+ }
+ rcu_read_unlock();
+
+ /* Cleanup minimum 10 milliseconds apart */
+ work_delay = max_t(unsigned long, work_delay, msecs_to_jiffies(10));
+ mod_delayed_work(system_long_wq, &br->gc_work, work_delay);
+}
+
+/* Completely flush all dynamic entries in forwarding database.*/
+void br_fdb_flush(struct net_bridge *br)
+{
+ struct net_bridge_fdb_entry *f;
+ struct hlist_node *tmp;
+
+ spin_lock_bh(&br->hash_lock);
+ hlist_for_each_entry_safe(f, tmp, &br->fdb_list, fdb_node) {
+ if (!test_bit(BR_FDB_STATIC, &f->flags))
+ fdb_delete(br, f, true);
+ }
+ spin_unlock_bh(&br->hash_lock);
+}
+
+/* Flush all entries referring to a specific port.
+ * if do_all is set also flush static entries
+ * if vid is set delete all entries that match the vlan_id
+ */
+void br_fdb_delete_by_port(struct net_bridge *br,
+ const struct net_bridge_port *p,
+ u16 vid,
+ int do_all)
+{
+ struct net_bridge_fdb_entry *f;
+ struct hlist_node *tmp;
+
+ spin_lock_bh(&br->hash_lock);
+ hlist_for_each_entry_safe(f, tmp, &br->fdb_list, fdb_node) {
+ if (f->dst != p)
+ continue;
+
+ if (!do_all)
+ if (test_bit(BR_FDB_STATIC, &f->flags) ||
+ (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags) &&
+ !test_bit(BR_FDB_OFFLOADED, &f->flags)) ||
+ (vid && f->key.vlan_id != vid))
+ continue;
+
+ if (test_bit(BR_FDB_LOCAL, &f->flags))
+ fdb_delete_local(br, p, f);
+ else
+ fdb_delete(br, f, true);
+ }
+ spin_unlock_bh(&br->hash_lock);
+}
+
+#if IS_ENABLED(CONFIG_ATM_LANE)
+/* Interface used by ATM LANE hook to test
+ * if an addr is on some other bridge port */
+int br_fdb_test_addr(struct net_device *dev, unsigned char *addr)
+{
+ struct net_bridge_fdb_entry *fdb;
+ struct net_bridge_port *port;
+ int ret;
+
+ rcu_read_lock();
+ port = br_port_get_rcu(dev);
+ if (!port)
+ ret = 0;
+ else {
+ fdb = br_fdb_find_rcu(port->br, addr, 0);
+ ret = fdb && fdb->dst && fdb->dst->dev != dev &&
+ fdb->dst->state == BR_STATE_FORWARDING;
+ }
+ rcu_read_unlock();
+
+ return ret;
+}
+#endif /* CONFIG_ATM_LANE */
+
+/*
+ * Fill buffer with forwarding table records in
+ * the API format.
+ */
+int br_fdb_fillbuf(struct net_bridge *br, void *buf,
+ unsigned long maxnum, unsigned long skip)
+{
+ struct net_bridge_fdb_entry *f;
+ struct __fdb_entry *fe = buf;
+ int num = 0;
+
+ memset(buf, 0, maxnum*sizeof(struct __fdb_entry));
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
+ if (num >= maxnum)
+ break;
+
+ if (has_expired(br, f))
+ continue;
+
+ /* ignore pseudo entry for local MAC address */
+ if (!f->dst)
+ continue;
+
+ if (skip) {
+ --skip;
+ continue;
+ }
+
+ /* convert from internal format to API */
+ memcpy(fe->mac_addr, f->key.addr.addr, ETH_ALEN);
+
+ /* due to ABI compat need to split into hi/lo */
+ fe->port_no = f->dst->port_no;
+ fe->port_hi = f->dst->port_no >> 8;
+
+ fe->is_local = test_bit(BR_FDB_LOCAL, &f->flags);
+ if (!test_bit(BR_FDB_STATIC, &f->flags))
+ fe->ageing_timer_value = jiffies_delta_to_clock_t(jiffies - f->updated);
+ ++fe;
+ ++num;
+ }
+ rcu_read_unlock();
+
+ return num;
+}
+
+static struct net_bridge_fdb_entry *fdb_create(struct net_bridge *br,
+ struct net_bridge_port *source,
+ const unsigned char *addr,
+ __u16 vid,
+ unsigned long flags)
+{
+ struct net_bridge_fdb_entry *fdb;
+
+ fdb = kmem_cache_alloc(br_fdb_cache, GFP_ATOMIC);
+ if (fdb) {
+ memcpy(fdb->key.addr.addr, addr, ETH_ALEN);
+ fdb->dst = source;
+ fdb->key.vlan_id = vid;
+ fdb->flags = flags;
+ fdb->updated = fdb->used = jiffies;
+ if (rhashtable_lookup_insert_fast(&br->fdb_hash_tbl,
+ &fdb->rhnode,
+ br_fdb_rht_params)) {
+ kmem_cache_free(br_fdb_cache, fdb);
+ fdb = NULL;
+ } else {
+ hlist_add_head_rcu(&fdb->fdb_node, &br->fdb_list);
+ }
+ }
+ return fdb;
+}
+
+static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
+ const unsigned char *addr, u16 vid)
+{
+ struct net_bridge_fdb_entry *fdb;
+
+ if (!is_valid_ether_addr(addr))
+ return -EINVAL;
+
+ fdb = br_fdb_find(br, addr, vid);
+ if (fdb) {
+ /* it is okay to have multiple ports with same
+ * address, just use the first one.
+ */
+ if (test_bit(BR_FDB_LOCAL, &fdb->flags))
+ return 0;
+ br_warn(br, "adding interface %s with same address as a received packet (addr:%pM, vlan:%u)\n",
+ source ? source->dev->name : br->dev->name, addr, vid);
+ fdb_delete(br, fdb, true);
+ }
+
+ fdb = fdb_create(br, source, addr, vid,
+ BIT(BR_FDB_LOCAL) | BIT(BR_FDB_STATIC));
+ if (!fdb)
+ return -ENOMEM;
+
+ fdb_add_hw_addr(br, addr);
+ fdb_notify(br, fdb, RTM_NEWNEIGH, true);
+ return 0;
+}
+
+/* Add entry for local address of interface */
+int br_fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
+ const unsigned char *addr, u16 vid)
+{
+ int ret;
+
+ spin_lock_bh(&br->hash_lock);
+ ret = fdb_insert(br, source, addr, vid);
+ spin_unlock_bh(&br->hash_lock);
+ return ret;
+}
+
+/* returns true if the fdb was modified */
+static bool __fdb_mark_active(struct net_bridge_fdb_entry *fdb)
+{
+ return !!(test_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags) &&
+ test_and_clear_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags));
+}
+
+void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
+ const unsigned char *addr, u16 vid, unsigned long flags)
+{
+ struct net_bridge_fdb_entry *fdb;
+
+ /* some users want to always flood. */
+ if (hold_time(br) == 0)
+ return;
+
+ fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
+ if (likely(fdb)) {
+ /* attempt to update an entry for a local interface */
+ if (unlikely(test_bit(BR_FDB_LOCAL, &fdb->flags))) {
+ if (net_ratelimit())
+ br_warn(br, "received packet on %s with own address as source address (addr:%pM, vlan:%u)\n",
+ source->dev->name, addr, vid);
+ } else {
+ unsigned long now = jiffies;
+ bool fdb_modified = false;
+
+ if (now != fdb->updated) {
+ fdb->updated = now;
+ fdb_modified = __fdb_mark_active(fdb);
+ }
+
+ /* fastpath: update of existing entry */
+ if (unlikely(source != fdb->dst &&
+ !test_bit(BR_FDB_STICKY, &fdb->flags))) {
+ fdb->dst = source;
+ fdb_modified = true;
+ /* Take over HW learned entry */
+ if (unlikely(test_bit(BR_FDB_ADDED_BY_EXT_LEARN,
+ &fdb->flags)))
+ clear_bit(BR_FDB_ADDED_BY_EXT_LEARN,
+ &fdb->flags);
+ }
+
+ if (unlikely(test_bit(BR_FDB_ADDED_BY_USER, &flags)))
+ set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
+ if (unlikely(fdb_modified)) {
+ trace_br_fdb_update(br, source, addr, vid, flags);
+ fdb_notify(br, fdb, RTM_NEWNEIGH, true);
+ }
+ }
+ } else {
+ spin_lock(&br->hash_lock);
+ fdb = fdb_create(br, source, addr, vid, flags);
+ if (fdb) {
+ trace_br_fdb_update(br, source, addr, vid, flags);
+ fdb_notify(br, fdb, RTM_NEWNEIGH, true);
+ }
+ /* else we lose race and someone else inserts
+ * it first, don't bother updating
+ */
+ spin_unlock(&br->hash_lock);
+ }
+}
+
+static int fdb_to_nud(const struct net_bridge *br,
+ const struct net_bridge_fdb_entry *fdb)
+{
+ if (test_bit(BR_FDB_LOCAL, &fdb->flags))
+ return NUD_PERMANENT;
+ else if (test_bit(BR_FDB_STATIC, &fdb->flags))
+ return NUD_NOARP;
+ else if (has_expired(br, fdb))
+ return NUD_STALE;
+ else
+ return NUD_REACHABLE;
+}
+
+static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br,
+ const struct net_bridge_fdb_entry *fdb,
+ u32 portid, u32 seq, int type, unsigned int flags)
+{
+ unsigned long now = jiffies;
+ struct nda_cacheinfo ci;
+ struct nlmsghdr *nlh;
+ struct ndmsg *ndm;
+
+ nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags);
+ if (nlh == NULL)
+ return -EMSGSIZE;
+
+ ndm = nlmsg_data(nlh);
+ ndm->ndm_family = AF_BRIDGE;
+ ndm->ndm_pad1 = 0;
+ ndm->ndm_pad2 = 0;
+ ndm->ndm_flags = 0;
+ ndm->ndm_type = 0;
+ ndm->ndm_ifindex = fdb->dst ? fdb->dst->dev->ifindex : br->dev->ifindex;
+ ndm->ndm_state = fdb_to_nud(br, fdb);
+
+ if (test_bit(BR_FDB_OFFLOADED, &fdb->flags))
+ ndm->ndm_flags |= NTF_OFFLOADED;
+ if (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags))
+ ndm->ndm_flags |= NTF_EXT_LEARNED;
+ if (test_bit(BR_FDB_STICKY, &fdb->flags))
+ ndm->ndm_flags |= NTF_STICKY;
+
+ if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->key.addr))
+ goto nla_put_failure;
+ if (nla_put_u32(skb, NDA_MASTER, br->dev->ifindex))
+ goto nla_put_failure;
+ ci.ndm_used = jiffies_to_clock_t(now - fdb->used);
+ ci.ndm_confirmed = 0;
+ ci.ndm_updated = jiffies_to_clock_t(now - fdb->updated);
+ ci.ndm_refcnt = 0;
+ if (nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
+ goto nla_put_failure;
+
+ if (fdb->key.vlan_id && nla_put(skb, NDA_VLAN, sizeof(u16),
+ &fdb->key.vlan_id))
+ goto nla_put_failure;
+
+ if (test_bit(BR_FDB_NOTIFY, &fdb->flags)) {
+ struct nlattr *nest = nla_nest_start(skb, NDA_FDB_EXT_ATTRS);
+ u8 notify_bits = FDB_NOTIFY_BIT;
+
+ if (!nest)
+ goto nla_put_failure;
+ if (test_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags))
+ notify_bits |= FDB_NOTIFY_INACTIVE_BIT;
+
+ if (nla_put_u8(skb, NFEA_ACTIVITY_NOTIFY, notify_bits)) {
+ nla_nest_cancel(skb, nest);
+ goto nla_put_failure;
+ }
+
+ nla_nest_end(skb, nest);
+ }
+
+ nlmsg_end(skb, nlh);
+ return 0;
+
+nla_put_failure:
+ nlmsg_cancel(skb, nlh);
+ return -EMSGSIZE;
+}
+
+static inline size_t fdb_nlmsg_size(void)
+{
+ return NLMSG_ALIGN(sizeof(struct ndmsg))
+ + nla_total_size(ETH_ALEN) /* NDA_LLADDR */
+ + nla_total_size(sizeof(u32)) /* NDA_MASTER */
+ + nla_total_size(sizeof(u16)) /* NDA_VLAN */
+ + nla_total_size(sizeof(struct nda_cacheinfo))
+ + nla_total_size(0) /* NDA_FDB_EXT_ATTRS */
+ + nla_total_size(sizeof(u8)); /* NFEA_ACTIVITY_NOTIFY */
+}
+
+static void fdb_notify(struct net_bridge *br,
+ const struct net_bridge_fdb_entry *fdb, int type,
+ bool swdev_notify)
+{
+ struct net *net = dev_net(br->dev);
+ struct sk_buff *skb;
+ int err = -ENOBUFS;
+
+ if (swdev_notify)
+ br_switchdev_fdb_notify(fdb, type);
+
+ skb = nlmsg_new(fdb_nlmsg_size(), GFP_ATOMIC);
+ if (skb == NULL)
+ goto errout;
+
+ err = fdb_fill_info(skb, br, fdb, 0, 0, type, 0);
+ if (err < 0) {
+ /* -EMSGSIZE implies BUG in fdb_nlmsg_size() */
+ WARN_ON(err == -EMSGSIZE);
+ kfree_skb(skb);
+ goto errout;
+ }
+ rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
+ return;
+errout:
+ rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
+}
+
+/* Dump information about entries, in response to GETNEIGH */
+int br_fdb_dump(struct sk_buff *skb,
+ struct netlink_callback *cb,
+ struct net_device *dev,
+ struct net_device *filter_dev,
+ int *idx)
+{
+ struct net_bridge *br = netdev_priv(dev);
+ struct net_bridge_fdb_entry *f;
+ int err = 0;
+
+ if (!(dev->priv_flags & IFF_EBRIDGE))
+ return err;
+
+ if (!filter_dev) {
+ err = ndo_dflt_fdb_dump(skb, cb, dev, NULL, idx);
+ if (err < 0)
+ return err;
+ }
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
+ if (*idx < cb->args[2])
+ goto skip;
+ if (filter_dev && (!f->dst || f->dst->dev != filter_dev)) {
+ if (filter_dev != dev)
+ goto skip;
+ /* !f->dst is a special case for bridge
+ * It means the MAC belongs to the bridge
+ * Therefore need a little more filtering
+ * we only want to dump the !f->dst case
+ */
+ if (f->dst)
+ goto skip;
+ }
+ if (!filter_dev && f->dst)
+ goto skip;
+
+ err = fdb_fill_info(skb, br, f,
+ NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq,
+ RTM_NEWNEIGH,
+ NLM_F_MULTI);
+ if (err < 0)
+ break;
+skip:
+ *idx += 1;
+ }
+ rcu_read_unlock();
+
+ return err;
+}
+
+int br_fdb_get(struct sk_buff *skb,
+ struct nlattr *tb[],
+ struct net_device *dev,
+ const unsigned char *addr,
+ u16 vid, u32 portid, u32 seq,
+ struct netlink_ext_ack *extack)
+{
+ struct net_bridge *br = netdev_priv(dev);
+ struct net_bridge_fdb_entry *f;
+ int err = 0;
+
+ rcu_read_lock();
+ f = br_fdb_find_rcu(br, addr, vid);
+ if (!f) {
+ NL_SET_ERR_MSG(extack, "Fdb entry not found");
+ err = -ENOENT;
+ goto errout;
+ }
+
+ err = fdb_fill_info(skb, br, f, portid, seq,
+ RTM_NEWNEIGH, 0);
+errout:
+ rcu_read_unlock();
+ return err;
+}
+
+/* returns true if the fdb is modified */
+static bool fdb_handle_notify(struct net_bridge_fdb_entry *fdb, u8 notify)
+{
+ bool modified = false;
+
+ /* allow to mark an entry as inactive, usually done on creation */
+ if ((notify & FDB_NOTIFY_INACTIVE_BIT) &&
+ !test_and_set_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags))
+ modified = true;
+
+ if ((notify & FDB_NOTIFY_BIT) &&
+ !test_and_set_bit(BR_FDB_NOTIFY, &fdb->flags)) {
+ /* enabled activity tracking */
+ modified = true;
+ } else if (!(notify & FDB_NOTIFY_BIT) &&
+ test_and_clear_bit(BR_FDB_NOTIFY, &fdb->flags)) {
+ /* disabled activity tracking, clear notify state */
+ clear_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags);
+ modified = true;
+ }
+
+ return modified;
+}
+
+/* Update (create or replace) forwarding database entry */
+static int fdb_add_entry(struct net_bridge *br, struct net_bridge_port *source,
+ const u8 *addr, struct ndmsg *ndm, u16 flags, u16 vid,
+ struct nlattr *nfea_tb[])
+{
+ bool is_sticky = !!(ndm->ndm_flags & NTF_STICKY);
+ bool refresh = !nfea_tb[NFEA_DONT_REFRESH];
+ struct net_bridge_fdb_entry *fdb;
+ u16 state = ndm->ndm_state;
+ bool modified = false;
+ u8 notify = 0;
+
+ /* If the port cannot learn allow only local and static entries */
+ if (source && !(state & NUD_PERMANENT) && !(state & NUD_NOARP) &&
+ !(source->state == BR_STATE_LEARNING ||
+ source->state == BR_STATE_FORWARDING))
+ return -EPERM;
+
+ if (!source && !(state & NUD_PERMANENT)) {
+ pr_info("bridge: RTM_NEWNEIGH %s without NUD_PERMANENT\n",
+ br->dev->name);
+ return -EINVAL;
+ }
+
+ if (is_sticky && (state & NUD_PERMANENT))
+ return -EINVAL;
+
+ if (nfea_tb[NFEA_ACTIVITY_NOTIFY]) {
+ notify = nla_get_u8(nfea_tb[NFEA_ACTIVITY_NOTIFY]);
+ if ((notify & ~BR_FDB_NOTIFY_SETTABLE_BITS) ||
+ (notify & BR_FDB_NOTIFY_SETTABLE_BITS) == FDB_NOTIFY_INACTIVE_BIT)
+ return -EINVAL;
+ }
+
+ fdb = br_fdb_find(br, addr, vid);
+ if (fdb == NULL) {
+ if (!(flags & NLM_F_CREATE))
+ return -ENOENT;
+
+ fdb = fdb_create(br, source, addr, vid, 0);
+ if (!fdb)
+ return -ENOMEM;
+
+ modified = true;
+ } else {
+ if (flags & NLM_F_EXCL)
+ return -EEXIST;
+
+ if (fdb->dst != source) {
+ fdb->dst = source;
+ modified = true;
+ }
+ }
+
+ if (fdb_to_nud(br, fdb) != state) {
+ if (state & NUD_PERMANENT) {
+ set_bit(BR_FDB_LOCAL, &fdb->flags);
+ if (!test_and_set_bit(BR_FDB_STATIC, &fdb->flags))
+ fdb_add_hw_addr(br, addr);
+ } else if (state & NUD_NOARP) {
+ clear_bit(BR_FDB_LOCAL, &fdb->flags);
+ if (!test_and_set_bit(BR_FDB_STATIC, &fdb->flags))
+ fdb_add_hw_addr(br, addr);
+ } else {
+ clear_bit(BR_FDB_LOCAL, &fdb->flags);
+ if (test_and_clear_bit(BR_FDB_STATIC, &fdb->flags))
+ fdb_del_hw_addr(br, addr);
+ }
+
+ modified = true;
+ }
+
+ if (is_sticky != test_bit(BR_FDB_STICKY, &fdb->flags)) {
+ change_bit(BR_FDB_STICKY, &fdb->flags);
+ modified = true;
+ }
+
+ if (fdb_handle_notify(fdb, notify))
+ modified = true;
+
+ set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
+
+ fdb->used = jiffies;
+ if (modified) {
+ if (refresh)
+ fdb->updated = jiffies;
+ fdb_notify(br, fdb, RTM_NEWNEIGH, true);
+ }
+
+ return 0;
+}
+
+static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge *br,
+ struct net_bridge_port *p, const unsigned char *addr,
+ u16 nlh_flags, u16 vid, struct nlattr *nfea_tb[],
+ struct netlink_ext_ack *extack)
+{
+ int err = 0;
+
+ if (ndm->ndm_flags & NTF_USE) {
+ if (!p) {
+ pr_info("bridge: RTM_NEWNEIGH %s with NTF_USE is not supported\n",
+ br->dev->name);
+ return -EINVAL;
+ }
+ if (!nbp_state_should_learn(p))
+ return 0;
+
+ local_bh_disable();
+ rcu_read_lock();
+ br_fdb_update(br, p, addr, vid, BIT(BR_FDB_ADDED_BY_USER));
+ rcu_read_unlock();
+ local_bh_enable();
+ } else if (ndm->ndm_flags & NTF_EXT_LEARNED) {
+ if (!p && !(ndm->ndm_state & NUD_PERMANENT)) {
+ NL_SET_ERR_MSG_MOD(extack,
+ "FDB entry towards bridge must be permanent");
+ return -EINVAL;
+ }
+ err = br_fdb_external_learn_add(br, p, addr, vid, true);
+ } else {
+ spin_lock_bh(&br->hash_lock);
+ err = fdb_add_entry(br, p, addr, ndm, nlh_flags, vid, nfea_tb);
+ spin_unlock_bh(&br->hash_lock);
+ }
+
+ return err;
+}
+
+static const struct nla_policy br_nda_fdb_pol[NFEA_MAX + 1] = {
+ [NFEA_ACTIVITY_NOTIFY] = { .type = NLA_U8 },
+ [NFEA_DONT_REFRESH] = { .type = NLA_FLAG },
+};
+
+/* Add new permanent fdb entry with RTM_NEWNEIGH */
+int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
+ struct net_device *dev,
+ const unsigned char *addr, u16 vid, u16 nlh_flags,
+ struct netlink_ext_ack *extack)
+{
+ struct nlattr *nfea_tb[NFEA_MAX + 1], *attr;
+ struct net_bridge_vlan_group *vg;
+ struct net_bridge_port *p = NULL;
+ struct net_bridge_vlan *v;
+ struct net_bridge *br = NULL;
+ int err = 0;
+
+ trace_br_fdb_add(ndm, dev, addr, vid, nlh_flags);
+
+ if (!(ndm->ndm_state & (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE))) {
+ pr_info("bridge: RTM_NEWNEIGH with invalid state %#x\n", ndm->ndm_state);
+ return -EINVAL;
+ }
+
+ if (is_zero_ether_addr(addr)) {
+ pr_info("bridge: RTM_NEWNEIGH with invalid ether address\n");
+ return -EINVAL;
+ }
+
+ if (dev->priv_flags & IFF_EBRIDGE) {
+ br = netdev_priv(dev);
+ vg = br_vlan_group(br);
+ } else {
+ p = br_port_get_rtnl(dev);
+ if (!p) {
+ pr_info("bridge: RTM_NEWNEIGH %s not a bridge port\n",
+ dev->name);
+ return -EINVAL;
+ }
+ br = p->br;
+ vg = nbp_vlan_group(p);
+ }
+
+ if (tb[NDA_FDB_EXT_ATTRS]) {
+ attr = tb[NDA_FDB_EXT_ATTRS];
+ err = nla_parse_nested(nfea_tb, NFEA_MAX, attr,
+ br_nda_fdb_pol, extack);
+ if (err)
+ return err;
+ } else {
+ memset(nfea_tb, 0, sizeof(struct nlattr *) * (NFEA_MAX + 1));
+ }
+
+ if (vid) {
+ v = br_vlan_find(vg, vid);
+ if (!v || !br_vlan_should_use(v)) {
+ pr_info("bridge: RTM_NEWNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
+ return -EINVAL;
+ }
+
+ /* VID was specified, so use it. */
+ err = __br_fdb_add(ndm, br, p, addr, nlh_flags, vid, nfea_tb,
+ extack);
+ } else {
+ err = __br_fdb_add(ndm, br, p, addr, nlh_flags, 0, nfea_tb,
+ extack);
+ if (err || !vg || !vg->num_vlans)
+ goto out;
+
+ /* We have vlans configured on this port and user didn't
+ * specify a VLAN. To be nice, add/update entry for every
+ * vlan on this port.
+ */
+ list_for_each_entry(v, &vg->vlan_list, vlist) {
+ if (!br_vlan_should_use(v))
+ continue;
+ err = __br_fdb_add(ndm, br, p, addr, nlh_flags, v->vid,
+ nfea_tb, extack);
+ if (err)
+ goto out;
+ }
+ }
+
+out:
+ return err;
+}
+
+static int fdb_delete_by_addr_and_port(struct net_bridge *br,
+ const struct net_bridge_port *p,
+ const u8 *addr, u16 vlan)
+{
+ struct net_bridge_fdb_entry *fdb;
+
+ fdb = br_fdb_find(br, addr, vlan);
+ if (!fdb || fdb->dst != p)
+ return -ENOENT;
+
+ fdb_delete(br, fdb, true);
+
+ return 0;
+}
+
+static int __br_fdb_delete(struct net_bridge *br,
+ const struct net_bridge_port *p,
+ const unsigned char *addr, u16 vid)
+{
+ int err;
+
+ spin_lock_bh(&br->hash_lock);
+ err = fdb_delete_by_addr_and_port(br, p, addr, vid);
+ spin_unlock_bh(&br->hash_lock);
+
+ return err;
+}
+
+/* Remove neighbor entry with RTM_DELNEIGH */
+int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
+ struct net_device *dev,
+ const unsigned char *addr, u16 vid)
+{
+ struct net_bridge_vlan_group *vg;
+ struct net_bridge_port *p = NULL;
+ struct net_bridge_vlan *v;
+ struct net_bridge *br;
+ int err;
+
+ if (dev->priv_flags & IFF_EBRIDGE) {
+ br = netdev_priv(dev);
+ vg = br_vlan_group(br);
+ } else {
+ p = br_port_get_rtnl(dev);
+ if (!p) {
+ pr_info("bridge: RTM_DELNEIGH %s not a bridge port\n",
+ dev->name);
+ return -EINVAL;
+ }
+ vg = nbp_vlan_group(p);
+ br = p->br;
+ }
+
+ if (vid) {
+ v = br_vlan_find(vg, vid);
+ if (!v) {
+ pr_info("bridge: RTM_DELNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
+ return -EINVAL;
+ }
+
+ err = __br_fdb_delete(br, p, addr, vid);
+ } else {
+ err = -ENOENT;
+ err &= __br_fdb_delete(br, p, addr, 0);
+ if (!vg || !vg->num_vlans)
+ return err;
+
+ list_for_each_entry(v, &vg->vlan_list, vlist) {
+ if (!br_vlan_should_use(v))
+ continue;
+ err &= __br_fdb_delete(br, p, addr, v->vid);
+ }
+ }
+
+ return err;
+}
+
+int br_fdb_sync_static(struct net_bridge *br, struct net_bridge_port *p)
+{
+ struct net_bridge_fdb_entry *f, *tmp;
+ int err = 0;
+
+ ASSERT_RTNL();
+
+ /* the key here is that static entries change only under rtnl */
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
+ /* We only care for static entries */
+ if (!test_bit(BR_FDB_STATIC, &f->flags))
+ continue;
+ err = dev_uc_add(p->dev, f->key.addr.addr);
+ if (err)
+ goto rollback;
+ }
+done:
+ rcu_read_unlock();
+
+ return err;
+
+rollback:
+ hlist_for_each_entry_rcu(tmp, &br->fdb_list, fdb_node) {
+ /* We only care for static entries */
+ if (!test_bit(BR_FDB_STATIC, &tmp->flags))
+ continue;
+ if (tmp == f)
+ break;
+ dev_uc_del(p->dev, tmp->key.addr.addr);
+ }
+
+ goto done;
+}
+
+void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p)
+{
+ struct net_bridge_fdb_entry *f;
+
+ ASSERT_RTNL();
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
+ /* We only care for static entries */
+ if (!test_bit(BR_FDB_STATIC, &f->flags))
+ continue;
+
+ dev_uc_del(p->dev, f->key.addr.addr);
+ }
+ rcu_read_unlock();
+}
+
+int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
+ const unsigned char *addr, u16 vid,
+ bool swdev_notify)
+{
+ struct net_bridge_fdb_entry *fdb;
+ bool modified = false;
+ int err = 0;
+
+ trace_br_fdb_external_learn_add(br, p, addr, vid);
+
+ spin_lock_bh(&br->hash_lock);
+
+ fdb = br_fdb_find(br, addr, vid);
+ if (!fdb) {
+ unsigned long flags = BIT(BR_FDB_ADDED_BY_EXT_LEARN);
+
+ if (swdev_notify)
+ flags |= BIT(BR_FDB_ADDED_BY_USER);
+
+ if (!p)
+ flags |= BIT(BR_FDB_LOCAL);
+
+ fdb = fdb_create(br, p, addr, vid, flags);
+ if (!fdb) {
+ err = -ENOMEM;
+ goto err_unlock;
+ }
+ fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
+ } else {
+ fdb->updated = jiffies;
+
+ if (fdb->dst != p) {
+ fdb->dst = p;
+ modified = true;
+ }
+
+ if (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags)) {
+ /* Refresh entry */
+ fdb->used = jiffies;
+ } else if (!test_bit(BR_FDB_ADDED_BY_USER, &fdb->flags)) {
+ /* Take over SW learned entry */
+ set_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags);
+ modified = true;
+ }
+
+ if (swdev_notify)
+ set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
+
+ if (!p)
+ set_bit(BR_FDB_LOCAL, &fdb->flags);
+
+ if (modified)
+ fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
+ }
+
+err_unlock:
+ spin_unlock_bh(&br->hash_lock);
+
+ return err;
+}
+
+int br_fdb_external_learn_del(struct net_bridge *br, struct net_bridge_port *p,
+ const unsigned char *addr, u16 vid,
+ bool swdev_notify)
+{
+ struct net_bridge_fdb_entry *fdb;
+ int err = 0;
+
+ spin_lock_bh(&br->hash_lock);
+
+ fdb = br_fdb_find(br, addr, vid);
+ if (fdb && test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags))
+ fdb_delete(br, fdb, swdev_notify);
+ else
+ err = -ENOENT;
+
+ spin_unlock_bh(&br->hash_lock);
+
+ return err;
+}
+
+void br_fdb_offloaded_set(struct net_bridge *br, struct net_bridge_port *p,
+ const unsigned char *addr, u16 vid, bool offloaded)
+{
+ struct net_bridge_fdb_entry *fdb;
+
+ spin_lock_bh(&br->hash_lock);
+
+ fdb = br_fdb_find(br, addr, vid);
+ if (fdb && offloaded != test_bit(BR_FDB_OFFLOADED, &fdb->flags))
+ change_bit(BR_FDB_OFFLOADED, &fdb->flags);
+
+ spin_unlock_bh(&br->hash_lock);
+}
+
+void br_fdb_clear_offload(const struct net_device *dev, u16 vid)
+{
+ struct net_bridge_fdb_entry *f;
+ struct net_bridge_port *p;
+
+ ASSERT_RTNL();
+
+ p = br_port_get_rtnl(dev);
+ if (!p)
+ return;
+
+ spin_lock_bh(&p->br->hash_lock);
+ hlist_for_each_entry(f, &p->br->fdb_list, fdb_node) {
+ if (f->dst == p && f->key.vlan_id == vid)
+ clear_bit(BR_FDB_OFFLOADED, &f->flags);
+ }
+ spin_unlock_bh(&p->br->hash_lock);
+}
+EXPORT_SYMBOL_GPL(br_fdb_clear_offload);