| /* |
| * Userspace interface |
| * Linux ethernet bridge |
| * |
| * Authors: |
| * Lennert Buytenhek <buytenh@gnu.org> |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/netdevice.h> |
| #include <linux/netpoll.h> |
| #include <linux/ethtool.h> |
| #include <linux/if_arp.h> |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include <linux/rtnetlink.h> |
| #include <linux/if_ether.h> |
| #include <linux/slab.h> |
| #include <net/sock.h> |
| |
| #include "br_private.h" |
| |
| /* |
| * Determine initial path cost based on speed. |
| * using recommendations from 802.1d standard |
| * |
| * Since driver might sleep need to not be holding any locks. |
| */ |
| static int port_cost(struct net_device *dev) |
| { |
| if (dev->ethtool_ops && dev->ethtool_ops->get_settings) { |
| struct ethtool_cmd ecmd = { .cmd = ETHTOOL_GSET, }; |
| |
| if (!dev->ethtool_ops->get_settings(dev, &ecmd)) { |
| switch(ecmd.speed) { |
| case SPEED_10000: |
| return 2; |
| case SPEED_1000: |
| return 4; |
| case SPEED_100: |
| return 19; |
| case SPEED_10: |
| return 100; |
| } |
| } |
| } |
| |
| /* Old silly heuristics based on name */ |
| if (!strncmp(dev->name, "lec", 3)) |
| return 7; |
| |
| if (!strncmp(dev->name, "plip", 4)) |
| return 2500; |
| |
| return 100; /* assume old 10Mbps */ |
| } |
| |
| |
| /* Check for port carrier transistions. */ |
| void br_port_carrier_check(struct net_bridge_port *p) |
| { |
| struct net_device *dev = p->dev; |
| struct net_bridge *br = p->br; |
| |
| if (netif_running(dev) && netif_carrier_ok(dev)) |
| p->path_cost = port_cost(dev); |
| |
| if (!netif_running(br->dev)) |
| return; |
| |
| spin_lock_bh(&br->lock); |
| if (netif_running(dev) && netif_carrier_ok(dev)) { |
| if (p->state == BR_STATE_DISABLED) |
| br_stp_enable_port(p); |
| } else { |
| if (p->state != BR_STATE_DISABLED) |
| br_stp_disable_port(p); |
| } |
| spin_unlock_bh(&br->lock); |
| } |
| |
| static void release_nbp(struct kobject *kobj) |
| { |
| struct net_bridge_port *p |
| = container_of(kobj, struct net_bridge_port, kobj); |
| kfree(p); |
| } |
| |
| static struct kobj_type brport_ktype = { |
| #ifdef CONFIG_SYSFS |
| .sysfs_ops = &brport_sysfs_ops, |
| #endif |
| .release = release_nbp, |
| }; |
| |
| static void destroy_nbp(struct net_bridge_port *p) |
| { |
| struct net_device *dev = p->dev; |
| |
| p->br = NULL; |
| p->dev = NULL; |
| dev_put(dev); |
| |
| kobject_put(&p->kobj); |
| } |
| |
| static void destroy_nbp_rcu(struct rcu_head *head) |
| { |
| struct net_bridge_port *p = |
| container_of(head, struct net_bridge_port, rcu); |
| destroy_nbp(p); |
| } |
| |
| /* Delete port(interface) from bridge is done in two steps. |
| * via RCU. First step, marks device as down. That deletes |
| * all the timers and stops new packets from flowing through. |
| * |
| * Final cleanup doesn't occur until after all CPU's finished |
| * processing packets. |
| * |
| * Protected from multiple admin operations by RTNL mutex |
| */ |
| static void del_nbp(struct net_bridge_port *p) |
| { |
| struct net_bridge *br = p->br; |
| struct net_device *dev = p->dev; |
| |
| sysfs_remove_link(br->ifobj, p->dev->name); |
| |
| dev_set_promiscuity(dev, -1); |
| |
| spin_lock_bh(&br->lock); |
| br_stp_disable_port(p); |
| spin_unlock_bh(&br->lock); |
| |
| br_ifinfo_notify(RTM_DELLINK, p); |
| |
| br_fdb_delete_by_port(br, p, 1); |
| |
| list_del_rcu(&p->list); |
| |
| dev->priv_flags &= ~IFF_BRIDGE_PORT; |
| |
| netdev_rx_handler_unregister(dev); |
| |
| br_multicast_del_port(p); |
| |
| kobject_uevent(&p->kobj, KOBJ_REMOVE); |
| kobject_del(&p->kobj); |
| |
| br_netpoll_disable(p); |
| |
| call_rcu(&p->rcu, destroy_nbp_rcu); |
| } |
| |
| /* called with RTNL */ |
| static void del_br(struct net_bridge *br, struct list_head *head) |
| { |
| struct net_bridge_port *p, *n; |
| |
| list_for_each_entry_safe(p, n, &br->port_list, list) { |
| del_nbp(p); |
| } |
| |
| del_timer_sync(&br->gc_timer); |
| |
| br_sysfs_delbr(br->dev); |
| unregister_netdevice_queue(br->dev, head); |
| } |
| |
| static struct net_device *new_bridge_dev(struct net *net, const char *name) |
| { |
| struct net_bridge *br; |
| struct net_device *dev; |
| |
| dev = alloc_netdev(sizeof(struct net_bridge), name, |
| br_dev_setup); |
| |
| if (!dev) |
| return NULL; |
| dev_net_set(dev, net); |
| |
| br = netdev_priv(dev); |
| br->dev = dev; |
| |
| br->stats = alloc_percpu(struct br_cpu_netstats); |
| if (!br->stats) { |
| free_netdev(dev); |
| return NULL; |
| } |
| |
| spin_lock_init(&br->lock); |
| INIT_LIST_HEAD(&br->port_list); |
| spin_lock_init(&br->hash_lock); |
| |
| br->bridge_id.prio[0] = 0x80; |
| br->bridge_id.prio[1] = 0x00; |
| |
| memcpy(br->group_addr, br_group_address, ETH_ALEN); |
| |
| br->feature_mask = dev->features; |
| br->stp_enabled = BR_NO_STP; |
| br->designated_root = br->bridge_id; |
| br->root_path_cost = 0; |
| br->root_port = 0; |
| br->bridge_max_age = br->max_age = 20 * HZ; |
| br->bridge_hello_time = br->hello_time = 2 * HZ; |
| br->bridge_forward_delay = br->forward_delay = 15 * HZ; |
| br->topology_change = 0; |
| br->topology_change_detected = 0; |
| br->ageing_time = 300 * HZ; |
| |
| br_netfilter_rtable_init(br); |
| |
| br_stp_timer_init(br); |
| br_multicast_init(br); |
| |
| return dev; |
| } |
| |
| /* find an available port number */ |
| static int find_portno(struct net_bridge *br) |
| { |
| int index; |
| struct net_bridge_port *p; |
| unsigned long *inuse; |
| |
| inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long), |
| GFP_KERNEL); |
| if (!inuse) |
| return -ENOMEM; |
| |
| set_bit(0, inuse); /* zero is reserved */ |
| list_for_each_entry(p, &br->port_list, list) { |
| set_bit(p->port_no, inuse); |
| } |
| index = find_first_zero_bit(inuse, BR_MAX_PORTS); |
| kfree(inuse); |
| |
| return (index >= BR_MAX_PORTS) ? -EXFULL : index; |
| } |
| |
| /* called with RTNL but without bridge lock */ |
| static struct net_bridge_port *new_nbp(struct net_bridge *br, |
| struct net_device *dev) |
| { |
| int index; |
| struct net_bridge_port *p; |
| |
| index = find_portno(br); |
| if (index < 0) |
| return ERR_PTR(index); |
| |
| p = kzalloc(sizeof(*p), GFP_KERNEL); |
| if (p == NULL) |
| return ERR_PTR(-ENOMEM); |
| |
| p->br = br; |
| dev_hold(dev); |
| p->dev = dev; |
| p->path_cost = port_cost(dev); |
| p->priority = 0x8000 >> BR_PORT_BITS; |
| p->port_no = index; |
| p->flags = 0; |
| br_init_port(p); |
| p->state = BR_STATE_DISABLED; |
| br_stp_port_timer_init(p); |
| br_multicast_add_port(p); |
| |
| return p; |
| } |
| |
| static struct device_type br_type = { |
| .name = "bridge", |
| }; |
| |
| int br_add_bridge(struct net *net, const char *name) |
| { |
| struct net_device *dev; |
| int ret; |
| |
| dev = new_bridge_dev(net, name); |
| if (!dev) |
| return -ENOMEM; |
| |
| rtnl_lock(); |
| if (strchr(dev->name, '%')) { |
| ret = dev_alloc_name(dev, dev->name); |
| if (ret < 0) |
| goto out_free; |
| } |
| |
| SET_NETDEV_DEVTYPE(dev, &br_type); |
| |
| ret = register_netdevice(dev); |
| if (ret) |
| goto out_free; |
| |
| ret = br_sysfs_addbr(dev); |
| if (ret) |
| unregister_netdevice(dev); |
| out: |
| rtnl_unlock(); |
| return ret; |
| |
| out_free: |
| free_netdev(dev); |
| goto out; |
| } |
| |
| int br_del_bridge(struct net *net, const char *name) |
| { |
| struct net_device *dev; |
| int ret = 0; |
| |
| rtnl_lock(); |
| dev = __dev_get_by_name(net, name); |
| if (dev == NULL) |
| ret = -ENXIO; /* Could not find device */ |
| |
| else if (!(dev->priv_flags & IFF_EBRIDGE)) { |
| /* Attempt to delete non bridge device! */ |
| ret = -EPERM; |
| } |
| |
| else if (dev->flags & IFF_UP) { |
| /* Not shutdown yet. */ |
| ret = -EBUSY; |
| } |
| |
| else |
| del_br(netdev_priv(dev), NULL); |
| |
| rtnl_unlock(); |
| return ret; |
| } |
| |
| /* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */ |
| int br_min_mtu(const struct net_bridge *br) |
| { |
| const struct net_bridge_port *p; |
| int mtu = 0; |
| |
| ASSERT_RTNL(); |
| |
| if (list_empty(&br->port_list)) |
| mtu = ETH_DATA_LEN; |
| else { |
| list_for_each_entry(p, &br->port_list, list) { |
| if (!mtu || p->dev->mtu < mtu) |
| mtu = p->dev->mtu; |
| } |
| } |
| return mtu; |
| } |
| |
| /* |
| * Recomputes features using slave's features |
| */ |
| void br_features_recompute(struct net_bridge *br) |
| { |
| struct net_bridge_port *p; |
| unsigned long features, mask; |
| |
| features = mask = br->feature_mask; |
| if (list_empty(&br->port_list)) |
| goto done; |
| |
| features &= ~NETIF_F_ONE_FOR_ALL; |
| |
| list_for_each_entry(p, &br->port_list, list) { |
| features = netdev_increment_features(features, |
| p->dev->features, mask); |
| } |
| |
| done: |
| br->dev->features = netdev_fix_features(features, NULL); |
| } |
| |
| /* called with RTNL */ |
| int br_add_if(struct net_bridge *br, struct net_device *dev) |
| { |
| struct net_bridge_port *p; |
| int err = 0; |
| |
| /* Don't allow bridging non-ethernet like devices */ |
| if ((dev->flags & IFF_LOOPBACK) || |
| dev->type != ARPHRD_ETHER || dev->addr_len != ETH_ALEN) |
| return -EINVAL; |
| |
| /* No bridging of bridges */ |
| if (dev->netdev_ops->ndo_start_xmit == br_dev_xmit) |
| return -ELOOP; |
| |
| /* Device is already being bridged */ |
| if (br_port_exists(dev)) |
| return -EBUSY; |
| |
| /* No bridging devices that dislike that (e.g. wireless) */ |
| if (dev->priv_flags & IFF_DONT_BRIDGE) |
| return -EOPNOTSUPP; |
| |
| p = new_nbp(br, dev); |
| if (IS_ERR(p)) |
| return PTR_ERR(p); |
| |
| err = dev_set_promiscuity(dev, 1); |
| if (err) |
| goto put_back; |
| |
| err = kobject_init_and_add(&p->kobj, &brport_ktype, &(dev->dev.kobj), |
| SYSFS_BRIDGE_PORT_ATTR); |
| if (err) |
| goto err0; |
| |
| err = br_fdb_insert(br, p, dev->dev_addr); |
| if (err) |
| goto err1; |
| |
| err = br_sysfs_addif(p); |
| if (err) |
| goto err2; |
| |
| if (br_netpoll_info(br) && ((err = br_netpoll_enable(p)))) |
| goto err3; |
| |
| err = netdev_rx_handler_register(dev, br_handle_frame, p); |
| if (err) |
| goto err3; |
| |
| dev->priv_flags |= IFF_BRIDGE_PORT; |
| |
| dev_disable_lro(dev); |
| |
| list_add_rcu(&p->list, &br->port_list); |
| |
| spin_lock_bh(&br->lock); |
| br_stp_recalculate_bridge_id(br); |
| br_features_recompute(br); |
| |
| if ((dev->flags & IFF_UP) && netif_carrier_ok(dev) && |
| (br->dev->flags & IFF_UP)) |
| br_stp_enable_port(p); |
| spin_unlock_bh(&br->lock); |
| |
| br_ifinfo_notify(RTM_NEWLINK, p); |
| |
| dev_set_mtu(br->dev, br_min_mtu(br)); |
| |
| kobject_uevent(&p->kobj, KOBJ_ADD); |
| |
| return 0; |
| err3: |
| sysfs_remove_link(br->ifobj, p->dev->name); |
| err2: |
| br_fdb_delete_by_port(br, p, 1); |
| err1: |
| kobject_put(&p->kobj); |
| p = NULL; /* kobject_put frees */ |
| err0: |
| dev_set_promiscuity(dev, -1); |
| put_back: |
| dev_put(dev); |
| kfree(p); |
| return err; |
| } |
| |
| /* called with RTNL */ |
| int br_del_if(struct net_bridge *br, struct net_device *dev) |
| { |
| struct net_bridge_port *p; |
| |
| p = br_port_get_rtnl(dev); |
| if (!p || p->br != br) |
| return -EINVAL; |
| |
| del_nbp(p); |
| |
| spin_lock_bh(&br->lock); |
| br_stp_recalculate_bridge_id(br); |
| br_features_recompute(br); |
| spin_unlock_bh(&br->lock); |
| |
| return 0; |
| } |
| |
| 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) |
| del_br(netdev_priv(dev), &list); |
| |
| unregister_netdevice_many(&list); |
| rtnl_unlock(); |
| |
| } |