// 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 <linux/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;
int __init br_fdb_init(void)
{
br_fdb_cache = KMEM_CACHE(net_bridge_fdb_entry, SLAB_HWCACHE_ALIGN);
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(READ_ONCE(fdb->updated) + hold_time(br), jiffies);
}
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)
{
const struct net_bridge_port *dst = READ_ONCE(fdb->dst);
unsigned long now = jiffies;
struct nda_cacheinfo ci;
struct nlmsghdr *nlh;
struct ndmsg *ndm;
u32 ext_flags = 0;
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 = dst ? 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 (test_bit(BR_FDB_LOCKED, &fdb->flags))
ext_flags |= NTF_EXT_LOCKED;
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;
if (nla_put_u32(skb, NDA_FLAGS_EXT, ext_f
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