| // SPDX-License-Identifier: GPL-2.0-or-later | 
 | /* | 
 |  *	Generic parts | 
 |  *	Linux ethernet bridge | 
 |  * | 
 |  *	Authors: | 
 |  *	Lennert Buytenhek		<buytenh@gnu.org> | 
 |  */ | 
 |  | 
 | #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 (dev->priv_flags & IFF_EBRIDGE) { | 
 | 		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 underlaying 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, false); | 
 | 		if (err) { | 
 | 			err = notifier_from_errno(err); | 
 | 			break; | 
 | 		} | 
 | 		br_fdb_offloaded_set(br, p, fdb_info->addr, | 
 | 				     fdb_info->vid, true); | 
 | 		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, | 
 | }; | 
 |  | 
 | /* 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) | 
 | { | 
 | 	switch (opt) { | 
 | 	case BR_BOOLOPT_NO_LL_LEARN: | 
 | 		br_opt_toggle(br, BROPT_NO_LL_LEARN, on); | 
 | 		break; | 
 | 	default: | 
 | 		/* shouldn't be called with unsupported options */ | 
 | 		WARN_ON(1); | 
 | 		break; | 
 | 	} | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | 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); | 
 | 	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(struct net *net) | 
 | { | 
 | 	struct net_device *dev; | 
 | 	LIST_HEAD(list); | 
 |  | 
 | 	rtnl_lock(); | 
 | 	for_each_netdev(net, dev) | 
 | 		if (dev->priv_flags & IFF_EBRIDGE) | 
 | 			br_dev_delete(dev, &list); | 
 |  | 
 | 	unregister_netdevice_many(&list); | 
 | 	rtnl_unlock(); | 
 |  | 
 | } | 
 |  | 
 | static struct pernet_operations br_net_ops = { | 
 | 	.exit	= br_net_exit, | 
 | }; | 
 |  | 
 | 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 = br_netlink_init(); | 
 | 	if (err) | 
 | 		goto err_out5; | 
 |  | 
 | 	brioctl_set(br_ioctl_deviceless_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_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_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"); |