// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Generic parts
* Linux ethernet bridge
*
* Authors:
* Lennert Buytenhek <[email protected]>
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/init.h>
#include <linux/llc.h>
#include <net/llc.h>
#include <net/stp.h>
#include <net/switchdev.h>
#include "br_private.h"
/*
* Handle changes in state of network devices enslaved to a bridge.
*
* Note: don't care about up/down if bridge itself is down, because
* port state is checked when bridge is brought up.
*/
static int br_device_event(struct notifier_block *unused, unsigned long event, void *ptr)
{
struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(ptr);
struct netdev_notifier_pre_changeaddr_info *prechaddr_info;
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
struct net_bridge_port *p;
struct net_bridge *br;
bool notified = false;
bool changed_addr;
int err;
if (netif_is_bridge_master(dev)) {
err = br_vlan_bridge_event(dev, event, ptr);
if (err)
return notifier_from_errno(err);
if (event == NETDEV_REGISTER) {
/* register of bridge completed, add sysfs entries */
err = br_sysfs_addbr(dev);
if (err)
return notifier_from_errno(err);
return NOTIFY_DONE;
}
}
/* not a port of a bridge */
p = br_port_get_rtnl(dev);
if (!p)
return NOTIFY_DONE;
br = p->br;
switch (event) {
case NETDEV_CHANGEMTU:
br_mtu_auto_adjust(br);
break;
case NETDEV_PRE_CHANGEADDR:
if (br->dev->addr_assign_type == NET_ADDR_SET)
break;
prechaddr_info = ptr;
err = dev_pre_changeaddr_notify(br->dev,
prechaddr_info->dev_addr,
extack);
if (err)
return notifier_from_errno(err);
break;
case NETDEV_CHANGEADDR:
spin_lock_bh(&br->lock);
br_fdb_changeaddr(p, dev->dev_addr);
changed_addr = br_stp_recalculate_bridge_id(br);
spin_unlock_bh(&br->lock);
if (changed_addr)
call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
break;
case NETDEV_CHANGE:
br_port_carrier_check(p, ¬ified);
break;
case NETDEV_FEAT_CHANGE:
netdev_update_features(br->dev);
break;
case NETDEV_DOWN:
spin_lock_bh(&br->lock);
if (br->dev->flags & IFF_UP) {
br_stp_disable_port(p);
notified = true;
}
spin_unlock_bh(&br->lock);
break;
case NETDEV_UP:
if (netif_running(br->dev) && netif_oper_up(dev)) {
spin_lock_bh(&br->lock);
br_stp_enable_port(p);
notified = true;
spin_unlock_bh(&br->lock);
}
break;
case NETDEV_UNREGISTER:
br_del_if(br, dev);
break;
case NETDEV_CHANGENAME:
err = br_sysfs_renameif(p);
if (err)
return notifier_from_errno(err);
break;
case NETDEV_PRE_TYPE_CHANGE:
/* Forbid underlying device to change its type. */
return NOTIFY_BAD;
case NETDEV_RESEND_IGMP:
/* Propagate to master device */
call_netdevice_notifiers(event, br->dev);
break;
}
if (event != NETDEV_UNREGISTER)
br_vlan_port_event(p, event);
/* Events that may cause spanning tree to refresh */
if (!notified && (event == NETDEV_CHANGEADDR || event == NETDEV_UP ||
event == NETDEV_CHANGE || event == NETDEV_DOWN))
br_ifinfo_notify(RTM_NEWLINK, NULL, p);
return NOTIFY_DONE;
}
static struct notifier_block br_device_notifier = {
.notifier_call = br_device_event
};
/* called with RTNL or RCU */
static int br_switchdev_event(struct notifier_block *unused,
unsigned long event, void *ptr)
{
struct net_device *dev = switchdev_notifier_info_to_dev(ptr);
struct net_bridge_port *p;
struct net_bridge *br;
struct switchdev_notifier_fdb_info *fdb_info;
int err = NOTIFY_DONE;
p = br_port_get_rtnl_rcu(dev);
if (!p)
goto out;
br = p->br;
switch (event) {
case SWITCHDEV_FDB_ADD_TO_BRIDGE:
fdb_info = ptr;
err = br_fdb_external_learn_add(br, p, fdb_info->addr,
fdb_info->vid,
fdb_info->locked, false);
if (err) {
err = notifier_from_errno(err);
break;
}
br_fdb_offloaded_set(br, p, fdb_info->addr,
fdb_info->vid, fdb_info->offloaded);
break;
case SWITCHDEV_FDB_DEL_TO_BRIDGE:
fdb_info = ptr;
err = br_fdb_external_learn_del(br, p, fdb_info->addr,
fdb_info->vid, false);
if (err)
err = notifier_from_errno(err);
break;
case SWITCHDEV_FDB_OFFLOADED:
fdb_info = ptr;
br_fdb_offloaded_set(br, p, fdb_info->addr,
fdb_info->vid, fdb_info->offloaded);
break;
case SWITCHDEV_FDB_FLUSH_TO_BRIDGE:
fdb_info = ptr;
/* Don't delete static entries */
br_fdb_delete_by_port(br, p, fdb_info->vid, 0);
break;
}
out:
return err;
}
static struct notifier_block br_switchdev_notifier = {
.notifier_call = br_switchdev_event,
};
/* called under rtnl_mutex */
static int br_switchdev_blocking_event(struct notifier_block *nb,
unsigned long event, void *ptr)
{
struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(ptr);
struct net_device *dev = switchdev_notifier_info_to_dev(ptr);
struct switchdev_notifier_brport_info *brport_info;
const struct switchdev_brport *b;
struct net_bridge_port *p;
int err = NOTIFY_DONE;
p = br_port_get_rtnl(dev);
if (!p)
goto out;
switch (event) {
case SWITCHDEV_BRPORT_OFFLOADED:
brport_info = ptr;
b = &brport_info->brport;
err = br_switchdev_port_offload(p, b->dev, b->ctx,
b->atomic_nb, b->blocking_nb,
b->tx_fwd_offload, extack);
err = notifier_from_errno(err);
break;
case SWITCHDEV_BRPORT_UNOFFLOADED:
brport_info = ptr;
b = &brport_info->brport;
br_switchdev_port_unoffload(p, b->ctx, b->atomic_nb,
b->blocking_nb);
break;
case SWITCHDEV_BRPORT_REPLAY:
brport_info = ptr;
b = &brport_info->brport;
err = br_switchdev_port_replay(p, b->dev, b->ctx, b->atomic_nb,
b->blocking_nb, extack);
err = notifier_from_errno(err);
break;
}
out:
return err;
}
static struct notifier_block br_switchdev_blocking_notifier = {
.notifier_call = br_switchdev_blocking_event,
};
/* br_boolopt_toggle - change user-controlled boolean option
*
* @br: bridge device
* @opt: id of the option to change
* @on: new option value
* @extack: extack for error messages
*
* Changes the value of the respective boolean option to @on taking care of
* any internal option value mapping and configuration.
*/
int br_boolopt_toggle(struct net_bridge *br, enum br_boolopt_id opt, bool on,
struct netlink_ext_ack *extack)
{
int err = 0;
switch (opt) {
case BR_BOOLOPT_NO_LL_LEARN:
br_opt_toggle(br, BROPT_NO_LL_LEARN, on);
break;
case BR_BOOLOPT_MCAST_VLAN_SNOOPING:
err = br_multicast_toggle_vlan_snooping(br, on, extack);
break;
case BR_BOOLOPT_MST_ENABLE:
err = br_mst_set_enabled(br, on, extack);
break;
default:
/* shouldn't be called with unsupported options */
WARN_ON(1);
break;
}
return err;
}
int br_boolopt_get(const struct net_bridge *br, enum br_boolopt_id opt)
{
switch (opt) {
case BR_BOOLOPT_NO_LL_LEARN:
return br_opt_get(br, BROPT_NO_LL_LEARN);
case BR_BOOLOPT_MCAST_VLAN_SNOOPING:
return br_opt_get(br, BROPT_MCAST_VLAN_SNOOPING_ENABLED);
case BR_BOOLOPT_MST_ENABLE:
return br_opt_get(br, BROPT_MST_ENABLED);
default:
/* shouldn't be called with unsupported options */
WARN_ON(1);
break;
}
return 0;
}
int br_boolopt_multi_toggle(struct net_bridge *br,
struct br_boolopt_multi *bm,
struct netlink_ext_ack *extack)
{
unsigned long bitmap = bm->optmask;
int err = 0;
int opt_id;
for_each_set_bit(opt_id, &bitmap, BR_BOOLOPT_MAX) {
bool on = !!(bm->optval & BIT(opt_id));
err = br_boolopt_toggle(br, opt_id, on, extack);
if (err) {
br_debug(br, "boolopt multi-toggle error: option: %d current: %d new: %d error: %d\n",
opt_id, br_boolopt_get(br, opt_id), on, err);
break;
}
}
return err;
}
void br_boolopt_multi_get(const struct net_bridge *br,
struct br_boolopt_multi *bm)
{
u32 optval = 0;
int opt_id;
for (opt_id = 0; opt_id < BR_BOOLOPT_MAX; opt_id++)
optval |= (br_boolopt_get(br, opt_id) << opt_id);
bm->optval = optval;
bm->optmask = GENMASK((BR_BOOLOPT_MAX - 1), 0);
}
/* private bridge options, controlled by the kernel */
void br_opt_toggle(struct net_bridge *br, enum net_bridge_opts opt, bool on)
{
bool cur = !!br_opt_get(br, opt);
br_debug(br, "toggle option: %d state: %d -> %d\n",
opt, cur, on);
if (cur == on)
return;
if (on)
set_bit(opt, &br->options);
else
clear_bit(opt, &br->options);
}
static void __net_exit br_net_exit_batch_rtnl(struct list_head *net_list,
struct list_head *dev_to_kill)
{
struct net_device *dev;
struct net *net;
ASSERT_RTNL();
list_for_each_entry(net, net_list, exit_list)
for_each_netdev(net, dev)
if (netif_is_bridge_master(dev))
br_dev_delete(dev, dev_to_kill);
}
static struct pernet_operations br_net_ops = {
.exit_batch_rtnl = br_net_exit_batch_rtnl,
};
static const struct stp_proto br_stp_proto = {
.rcv = br_stp_rcv,
};
static int __init br_init(void)
{
int err;
BUILD_BUG_ON(sizeof(struct br_input_skb_cb) > sizeof_field(struct sk_buff, cb));
err = stp_proto_register(&br_stp_proto);
if (err < 0) {
pr_err("bridge: can't register sap for STP\n");
return err;
}
err = br_fdb_init();
if (err)
goto err_out;
err = register_pernet_subsys(&br_net_ops);
if (err)
goto err_out1;
err = br_nf_core_init();
if (err)
goto err_out2;
err = register_netdevice_notifier(&br_device_notifier);
if (err)
goto err_out3;
err = register_switchdev_notifier(&br_switchdev_notifier);
if (err)
goto err_out4;
err = register_switchdev_blocking_notifier(&br_switchdev_blocking_notifier);
if (err)
goto err_out5;
err = br_netlink_init();
if (err)
goto err_out6;
brioctl_set(br_ioctl_stub);
#if IS_ENABLED(CONFIG_ATM_LANE)
br_fdb_test_addr_hook = br_fdb_test_addr;
#endif
#if IS_MODULE(CONFIG_BRIDGE_NETFILTER)
pr_info("bridge: filtering via arp/ip/ip6tables is no longer available "
"by default. Update your scripts to load br_netfilter if you "
"need this.\n");
#endif
return 0;
err_out6:
unregister_switchdev_blocking_notifier(&br_switchdev_blocking_notifier);
err_out5:
unregister_switchdev_notifier(&br_switchdev_notifier);
err_out4:
unregister_netdevice_notifier(&br_device_notifier);
err_out3:
br_nf_core_fini();
err_out2:
unregister_pernet_subsys(&br_net_ops);
err_out1:
br_fdb_fini();
err_out:
stp_proto_unregister(&br_stp_proto);
return err;
}
static void __exit br_deinit(void)
{
stp_proto_unregister(&br_stp_proto);
br_netlink_fini();
unregister_switchdev_blocking_notifier(&br_switchdev_blocking_notifier);
unregister_switchdev_notifier(&br_switchdev_notifier);
unregister_netdevice_notifier(&br_device_notifier);
brioctl_set(NULL);
unregister_pernet_subsys(&br_net_ops);
rcu_barrier(); /* Wait for completion of call_rcu()'s */
br_nf_core_fini();
#if IS_ENABLED(CONFIG_ATM_LANE)
br_fdb_test_addr_hook = NULL;
#endif
br_fdb_fini();
}
module_init(br_init)
module_exit(br_deinit)
MODULE_LICENSE("GPL");
MODULE_VERSION(BR_VERSION);
MODULE_ALIAS_RTNL_LINK("bridge");
MODULE_DESCRIPTION("Ethernet bridge driver");
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