1 files changed, 406 insertions, 0 deletions
diff --git a/net/bridge/br.c b/net/bridge/br.c
new file mode 100644
index 000000000..1b169f8e7
--- /dev/null
+++ b/net/bridge/br.c
@@ -0,0 +1,406 @@
+// 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, &notified);
+		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");