diff options
Diffstat (limited to 'net/batman-adv/hard-interface.c')
| -rw-r--r-- | net/batman-adv/hard-interface.c | 651 |
1 files changed, 651 insertions, 0 deletions
diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c new file mode 100644 index 000000000000..4f95777ce080 --- /dev/null +++ b/net/batman-adv/hard-interface.c @@ -0,0 +1,651 @@ +/* + * Copyright (C) 2007-2010 B.A.T.M.A.N. contributors: + * + * Marek Lindner, Simon Wunderlich + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA + * + */ + +#include "main.h" +#include "hard-interface.h" +#include "soft-interface.h" +#include "send.h" +#include "translation-table.h" +#include "routing.h" +#include "bat_sysfs.h" +#include "originator.h" +#include "hash.h" + +#include <linux/if_arp.h> + +/* protect update critical side of if_list - but not the content */ +static DEFINE_SPINLOCK(if_list_lock); + +static void hardif_free_rcu(struct rcu_head *rcu) +{ + struct batman_if *batman_if; + + batman_if = container_of(rcu, struct batman_if, rcu); + dev_put(batman_if->net_dev); + kref_put(&batman_if->refcount, hardif_free_ref); +} + +struct batman_if *get_batman_if_by_netdev(struct net_device *net_dev) +{ + struct batman_if *batman_if; + + rcu_read_lock(); + list_for_each_entry_rcu(batman_if, &if_list, list) { + if (batman_if->net_dev == net_dev) + goto out; + } + + batman_if = NULL; + +out: + if (batman_if) + kref_get(&batman_if->refcount); + + rcu_read_unlock(); + return batman_if; +} + +static int is_valid_iface(struct net_device *net_dev) +{ + if (net_dev->flags & IFF_LOOPBACK) + return 0; + + if (net_dev->type != ARPHRD_ETHER) + return 0; + + if (net_dev->addr_len != ETH_ALEN) + return 0; + + /* no batman over batman */ +#ifdef HAVE_NET_DEVICE_OPS + if (net_dev->netdev_ops->ndo_start_xmit == interface_tx) + return 0; +#else + if (net_dev->hard_start_xmit == interface_tx) + return 0; +#endif + + /* Device is being bridged */ + /* if (net_dev->priv_flags & IFF_BRIDGE_PORT) + return 0; */ + + return 1; +} + +static struct batman_if *get_active_batman_if(struct net_device *soft_iface) +{ + struct batman_if *batman_if; + + rcu_read_lock(); + list_for_each_entry_rcu(batman_if, &if_list, list) { + if (batman_if->soft_iface != soft_iface) + continue; + + if (batman_if->if_status == IF_ACTIVE) + goto out; + } + + batman_if = NULL; + +out: + if (batman_if) + kref_get(&batman_if->refcount); + + rcu_read_unlock(); + return batman_if; +} + +static void update_primary_addr(struct bat_priv *bat_priv) +{ + struct vis_packet *vis_packet; + + vis_packet = (struct vis_packet *) + bat_priv->my_vis_info->skb_packet->data; + memcpy(vis_packet->vis_orig, + bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN); + memcpy(vis_packet->sender_orig, + bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN); +} + +static void set_primary_if(struct bat_priv *bat_priv, + struct batman_if *batman_if) +{ + struct batman_packet *batman_packet; + struct batman_if *old_if; + + if (batman_if) + kref_get(&batman_if->refcount); + + old_if = bat_priv->primary_if; + bat_priv->primary_if = batman_if; + + if (old_if) + kref_put(&old_if->refcount, hardif_free_ref); + + if (!bat_priv->primary_if) + return; + + batman_packet = (struct batman_packet *)(batman_if->packet_buff); + batman_packet->flags = PRIMARIES_FIRST_HOP; + batman_packet->ttl = TTL; + + update_primary_addr(bat_priv); + + /*** + * hacky trick to make sure that we send the HNA information via + * our new primary interface + */ + atomic_set(&bat_priv->hna_local_changed, 1); +} + +static bool hardif_is_iface_up(struct batman_if *batman_if) +{ + if (batman_if->net_dev->flags & IFF_UP) + return true; + + return false; +} + +static void update_mac_addresses(struct batman_if *batman_if) +{ + memcpy(((struct batman_packet *)(batman_if->packet_buff))->orig, + batman_if->net_dev->dev_addr, ETH_ALEN); + memcpy(((struct batman_packet *)(batman_if->packet_buff))->prev_sender, + batman_if->net_dev->dev_addr, ETH_ALEN); +} + +static void check_known_mac_addr(struct net_device *net_dev) +{ + struct batman_if *batman_if; + + rcu_read_lock(); + list_for_each_entry_rcu(batman_if, &if_list, list) { + if ((batman_if->if_status != IF_ACTIVE) && + (batman_if->if_status != IF_TO_BE_ACTIVATED)) + continue; + + if (batman_if->net_dev == net_dev) + continue; + + if (!compare_orig(batman_if->net_dev->dev_addr, + net_dev->dev_addr)) + continue; + + pr_warning("The newly added mac address (%pM) already exists " + "on: %s\n", net_dev->dev_addr, + batman_if->net_dev->name); + pr_warning("It is strongly recommended to keep mac addresses " + "unique to avoid problems!\n"); + } + rcu_read_unlock(); +} + +int hardif_min_mtu(struct net_device *soft_iface) +{ + struct bat_priv *bat_priv = netdev_priv(soft_iface); + struct batman_if *batman_if; + /* allow big frames if all devices are capable to do so + * (have MTU > 1500 + BAT_HEADER_LEN) */ + int min_mtu = ETH_DATA_LEN; + + if (atomic_read(&bat_priv->fragmentation)) + goto out; + + rcu_read_lock(); + list_for_each_entry_rcu(batman_if, &if_list, list) { + if ((batman_if->if_status != IF_ACTIVE) && + (batman_if->if_status != IF_TO_BE_ACTIVATED)) + continue; + + if (batman_if->soft_iface != soft_iface) + continue; + + min_mtu = min_t(int, batman_if->net_dev->mtu - BAT_HEADER_LEN, + min_mtu); + } + rcu_read_unlock(); +out: + return min_mtu; +} + +/* adjusts the MTU if a new interface with a smaller MTU appeared. */ +void update_min_mtu(struct net_device *soft_iface) +{ + int min_mtu; + + min_mtu = hardif_min_mtu(soft_iface); + if (soft_iface->mtu != min_mtu) + soft_iface->mtu = min_mtu; +} + +static void hardif_activate_interface(struct batman_if *batman_if) +{ + struct bat_priv *bat_priv; + + if (batman_if->if_status != IF_INACTIVE) + return; + + bat_priv = netdev_priv(batman_if->soft_iface); + + update_mac_addresses(batman_if); + batman_if->if_status = IF_TO_BE_ACTIVATED; + + /** + * the first active interface becomes our primary interface or + * the next active interface after the old primay interface was removed + */ + if (!bat_priv->primary_if) + set_primary_if(bat_priv, batman_if); + + bat_info(batman_if->soft_iface, "Interface activated: %s\n", + batman_if->net_dev->name); + + update_min_mtu(batman_if->soft_iface); + return; +} + +static void hardif_deactivate_interface(struct batman_if *batman_if) +{ + if ((batman_if->if_status != IF_ACTIVE) && + (batman_if->if_status != IF_TO_BE_ACTIVATED)) + return; + + batman_if->if_status = IF_INACTIVE; + + bat_info(batman_if->soft_iface, "Interface deactivated: %s\n", + batman_if->net_dev->name); + + update_min_mtu(batman_if->soft_iface); +} + +int hardif_enable_interface(struct batman_if *batman_if, char *iface_name) +{ + struct bat_priv *bat_priv; + struct batman_packet *batman_packet; + + if (batman_if->if_status != IF_NOT_IN_USE) + goto out; + + batman_if->soft_iface = dev_get_by_name(&init_net, iface_name); + + if (!batman_if->soft_iface) { + batman_if->soft_iface = softif_create(iface_name); + + if (!batman_if->soft_iface) + goto err; + + /* dev_get_by_name() increases the reference counter for us */ + dev_hold(batman_if->soft_iface); + } + + bat_priv = netdev_priv(batman_if->soft_iface); + batman_if->packet_len = BAT_PACKET_LEN; + batman_if->packet_buff = kmalloc(batman_if->packet_len, GFP_ATOMIC); + + if (!batman_if->packet_buff) { + bat_err(batman_if->soft_iface, "Can't add interface packet " + "(%s): out of memory\n", batman_if->net_dev->name); + goto err; + } + + batman_packet = (struct batman_packet *)(batman_if->packet_buff); + batman_packet->packet_type = BAT_PACKET; + batman_packet->version = COMPAT_VERSION; + batman_packet->flags = 0; + batman_packet->ttl = 2; + batman_packet->tq = TQ_MAX_VALUE; + batman_packet->num_hna = 0; + + batman_if->if_num = bat_priv->num_ifaces; + bat_priv->num_ifaces++; + batman_if->if_status = IF_INACTIVE; + orig_hash_add_if(batman_if, bat_priv->num_ifaces); + + batman_if->batman_adv_ptype.type = __constant_htons(ETH_P_BATMAN); + batman_if->batman_adv_ptype.func = batman_skb_recv; + batman_if->batman_adv_ptype.dev = batman_if->net_dev; + kref_get(&batman_if->refcount); + dev_add_pack(&batman_if->batman_adv_ptype); + + atomic_set(&batman_if->seqno, 1); + atomic_set(&batman_if->frag_seqno, 1); + bat_info(batman_if->soft_iface, "Adding interface: %s\n", + batman_if->net_dev->name); + + if (atomic_read(&bat_priv->fragmentation) && batman_if->net_dev->mtu < + ETH_DATA_LEN + BAT_HEADER_LEN) + bat_info(batman_if->soft_iface, + "The MTU of interface %s is too small (%i) to handle " + "the transport of batman-adv packets. Packets going " + "over this interface will be fragmented on layer2 " + "which could impact the performance. Setting the MTU " + "to %zi would solve the problem.\n", + batman_if->net_dev->name, batman_if->net_dev->mtu, + ETH_DATA_LEN + BAT_HEADER_LEN); + + if (!atomic_read(&bat_priv->fragmentation) && batman_if->net_dev->mtu < + ETH_DATA_LEN + BAT_HEADER_LEN) + bat_info(batman_if->soft_iface, + "The MTU of interface %s is too small (%i) to handle " + "the transport of batman-adv packets. If you experience" + " problems getting traffic through try increasing the " + "MTU to %zi.\n", + batman_if->net_dev->name, batman_if->net_dev->mtu, + ETH_DATA_LEN + BAT_HEADER_LEN); + + if (hardif_is_iface_up(batman_if)) + hardif_activate_interface(batman_if); + else + bat_err(batman_if->soft_iface, "Not using interface %s " + "(retrying later): interface not active\n", + batman_if->net_dev->name); + + /* begin scheduling originator messages on that interface */ + schedule_own_packet(batman_if); + +out: + return 0; + +err: + return -ENOMEM; +} + +void hardif_disable_interface(struct batman_if *batman_if) +{ + struct bat_priv *bat_priv = netdev_priv(batman_if->soft_iface); + + if (batman_if->if_status == IF_ACTIVE) + hardif_deactivate_interface(batman_if); + + if (batman_if->if_status != IF_INACTIVE) + return; + + bat_info(batman_if->soft_iface, "Removing interface: %s\n", + batman_if->net_dev->name); + dev_remove_pack(&batman_if->batman_adv_ptype); + kref_put(&batman_if->refcount, hardif_free_ref); + + bat_priv->num_ifaces--; + orig_hash_del_if(batman_if, bat_priv->num_ifaces); + + if (batman_if == bat_priv->primary_if) { + struct batman_if *new_if; + + new_if = get_active_batman_if(batman_if->soft_iface); + set_primary_if(bat_priv, new_if); + + if (new_if) + kref_put(&new_if->refcount, hardif_free_ref); + } + + kfree(batman_if->packet_buff); + batman_if->packet_buff = NULL; + batman_if->if_status = IF_NOT_IN_USE; + + /* delete all references to this batman_if */ + purge_orig_ref(bat_priv); + purge_outstanding_packets(bat_priv, batman_if); + dev_put(batman_if->soft_iface); + + /* nobody uses this interface anymore */ + if (!bat_priv->num_ifaces) + softif_destroy(batman_if->soft_iface); + + batman_if->soft_iface = NULL; +} + +static struct batman_if *hardif_add_interface(struct net_device *net_dev) +{ + struct batman_if *batman_if; + int ret; + + ret = is_valid_iface(net_dev); + if (ret != 1) + goto out; + + dev_hold(net_dev); + + batman_if = kmalloc(sizeof(struct batman_if), GFP_ATOMIC); + if (!batman_if) { + pr_err("Can't add interface (%s): out of memory\n", + net_dev->name); + goto release_dev; + } + + ret = sysfs_add_hardif(&batman_if->hardif_obj, net_dev); + if (ret) + goto free_if; + + batman_if->if_num = -1; + batman_if->net_dev = net_dev; + batman_if->soft_iface = NULL; + batman_if->if_status = IF_NOT_IN_USE; + INIT_LIST_HEAD(&batman_if->list); + kref_init(&batman_if->refcount); + + check_known_mac_addr(batman_if->net_dev); + + spin_lock(&if_list_lock); + list_add_tail_rcu(&batman_if->list, &if_list); + spin_unlock(&if_list_lock); + + /* extra reference for return */ + kref_get(&batman_if->refcount); + return batman_if; + +free_if: + kfree(batman_if); +release_dev: + dev_put(net_dev); +out: + return NULL; +} + +static void hardif_remove_interface(struct batman_if *batman_if) +{ + /* first deactivate interface */ + if (batman_if->if_status != IF_NOT_IN_USE) + hardif_disable_interface(batman_if); + + if (batman_if->if_status != IF_NOT_IN_USE) + return; + + batman_if->if_status = IF_TO_BE_REMOVED; + sysfs_del_hardif(&batman_if->hardif_obj); + call_rcu(&batman_if->rcu, hardif_free_rcu); +} + +void hardif_remove_interfaces(void) +{ + struct batman_if *batman_if, *batman_if_tmp; + struct list_head if_queue; + + INIT_LIST_HEAD(&if_queue); + + spin_lock(&if_list_lock); + list_for_each_entry_safe(batman_if, batman_if_tmp, &if_list, list) { + list_del_rcu(&batman_if->list); + list_add_tail(&batman_if->list, &if_queue); + } + spin_unlock(&if_list_lock); + + rtnl_lock(); + list_for_each_entry_safe(batman_if, batman_if_tmp, &if_queue, list) { + hardif_remove_interface(batman_if); + } + rtnl_unlock(); +} + +static int hard_if_event(struct notifier_block *this, + unsigned long event, void *ptr) +{ + struct net_device *net_dev = (struct net_device *)ptr; + struct batman_if *batman_if = get_batman_if_by_netdev(net_dev); + struct bat_priv *bat_priv; + + if (!batman_if && event == NETDEV_REGISTER) + batman_if = hardif_add_interface(net_dev); + + if (!batman_if) + goto out; + + switch (event) { + case NETDEV_UP: + hardif_activate_interface(batman_if); + break; + case NETDEV_GOING_DOWN: + case NETDEV_DOWN: + hardif_deactivate_interface(batman_if); + break; + case NETDEV_UNREGISTER: + spin_lock(&if_list_lock); + list_del_rcu(&batman_if->list); + spin_unlock(&if_list_lock); + + hardif_remove_interface(batman_if); + break; + case NETDEV_CHANGEMTU: + if (batman_if->soft_iface) + update_min_mtu(batman_if->soft_iface); + break; + case NETDEV_CHANGEADDR: + if (batman_if->if_status == IF_NOT_IN_USE) + goto hardif_put; + + check_known_mac_addr(batman_if->net_dev); + update_mac_addresses(batman_if); + + bat_priv = netdev_priv(batman_if->soft_iface); + if (batman_if == bat_priv->primary_if) + update_primary_addr(bat_priv); + break; + default: + break; + }; + +hardif_put: + kref_put(&batman_if->refcount, hardif_free_ref); +out: + return NOTIFY_DONE; +} + +/* receive a packet with the batman ethertype coming on a hard + * interface */ +int batman_skb_recv(struct sk_buff *skb, struct net_device *dev, + struct packet_type *ptype, struct net_device *orig_dev) +{ + struct bat_priv *bat_priv; + struct batman_packet *batman_packet; + struct batman_if *batman_if; + int ret; + + batman_if = container_of(ptype, struct batman_if, batman_adv_ptype); + skb = skb_share_check(skb, GFP_ATOMIC); + + /* skb was released by skb_share_check() */ + if (!skb) + goto err_out; + + /* packet should hold at least type and version */ + if (unlikely(!pskb_may_pull(skb, 2))) + goto err_free; + + /* expect a valid ethernet header here. */ + if (unlikely(skb->mac_len != sizeof(struct ethhdr) + || !skb_mac_header(skb))) + goto err_free; + + if (!batman_if->soft_iface) + goto err_free; + + bat_priv = netdev_priv(batman_if->soft_iface); + + if (atomic_read(&bat_priv->mesh_state) != MESH_ACTIVE) + goto err_free; + + /* discard frames on not active interfaces */ + if (batman_if->if_status != IF_ACTIVE) + goto err_free; + + batman_packet = (struct batman_packet *)skb->data; + + if (batman_packet->version != COMPAT_VERSION) { + bat_dbg(DBG_BATMAN, bat_priv, + "Drop packet: incompatible batman version (%i)\n", + batman_packet->version); + goto err_free; + } + + /* all receive handlers return whether they received or reused + * the supplied skb. if not, we have to free the skb. */ + + switch (batman_packet->packet_type) { + /* batman originator packet */ + case BAT_PACKET: + ret = recv_bat_packet(skb, batman_if); + break; + + /* batman icmp packet */ + case BAT_ICMP: + ret = recv_icmp_packet(skb, batman_if); + break; + + /* unicast packet */ + case BAT_UNICAST: + ret = recv_unicast_packet(skb, batman_if); + break; + + /* fragmented unicast packet */ + case BAT_UNICAST_FRAG: + ret = recv_ucast_frag_packet(skb, batman_if); + break; + + /* broadcast packet */ + case BAT_BCAST: + ret = recv_bcast_packet(skb, batman_if); + break; + + /* vis packet */ + case BAT_VIS: + ret = recv_vis_packet(skb, batman_if); + break; + default: + ret = NET_RX_DROP; + } + + if (ret == NET_RX_DROP) + kfree_skb(skb); + + /* return NET_RX_SUCCESS in any case as we + * most probably dropped the packet for + * routing-logical reasons. */ + + return NET_RX_SUCCESS; + +err_free: + kfree_skb(skb); +err_out: + return NET_RX_DROP; +} + +struct notifier_block hard_if_notifier = { + .notifier_call = hard_if_event, +}; |