/* * Copyright (C) 2007-2012 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> static int batman_skb_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *ptype, struct net_device *orig_dev); void hardif_free_rcu(struct rcu_head *rcu) { struct hard_iface *hard_iface; hard_iface = container_of(rcu, struct hard_iface, rcu); dev_put(hard_iface->net_dev); kfree(hard_iface); } struct hard_iface *hardif_get_by_netdev(const struct net_device *net_dev) { struct hard_iface *hard_iface; rcu_read_lock(); list_for_each_entry_rcu(hard_iface, &hardif_list, list) { if (hard_iface->net_dev == net_dev && atomic_inc_not_zero(&hard_iface->refcount)) goto out; } hard_iface = NULL; out: rcu_read_unlock(); return hard_iface; } static int is_valid_iface(const 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 */ if (softif_is_valid(net_dev)) return 0; /* Device is being bridged */ /* if (net_dev->priv_flags & IFF_BRIDGE_PORT) return 0; */ return 1; } static struct hard_iface *hardif_get_active(const struct net_device *soft_iface) { struct hard_iface *hard_iface; rcu_read_lock(); list_for_each_entry_rcu(hard_iface, &hardif_list, list) { if (hard_iface->soft_iface != soft_iface) continue; if (hard_iface->if_status == IF_ACTIVE && atomic_inc_not_zero(&hard_iface->refcount)) goto out; } hard_iface = NULL; out: rcu_read_unlock(); return hard_iface; } static void primary_if_update_addr(struct bat_priv *bat_priv) { struct vis_packet *vis_packet; struct hard_iface *primary_if; primary_if = primary_if_get_selected(bat_priv); if (!primary_if) goto out; vis_packet = (struct vis_packet *) bat_priv->my_vis_info->skb_packet->data; memcpy(vis_packet->vis_orig, primary_if->net_dev->dev_addr, ETH_ALEN); memcpy(vis_packet->sender_orig, primary_if->net_dev->dev_addr, ETH_ALEN); out: if (primary_if) hardif_free_ref(primary_if); } static void primary_if_select(struct bat_priv *bat_priv, struct hard_iface *new_hard_iface) { struct hard_iface *curr_hard_iface; ASSERT_RTNL(); if (new_hard_iface && !atomic_inc_not_zero(&new_hard_iface->refcount)) new_hard_iface = NULL; curr_hard_iface = rcu_dereference_protected(bat_priv->primary_if, 1); rcu_assign_pointer(bat_priv->primary_if, new_hard_iface); if (curr_hard_iface) hardif_free_ref(curr_hard_iface); if (!new_hard_iface) return; bat_priv->bat_algo_ops->bat_ogm_init_primary(new_hard_iface); primary_if_update_addr(bat_priv); } static bool hardif_is_iface_up(const struct hard_iface *hard_iface) { if (hard_iface->net_dev->flags & IFF_UP) return true; return false; } static void check_known_mac_addr(const struct net_device *net_dev) { const struct hard_iface *hard_iface; rcu_read_lock(); list_for_each_entry_rcu(hard_iface, &hardif_list, list) { if ((hard_iface->if_status != IF_ACTIVE) && (hard_iface->if_status != IF_TO_BE_ACTIVATED)) continue; if (hard_iface->net_dev == net_dev) continue; if (!compare_eth(hard_iface->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, hard_iface->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) { const struct bat_priv *bat_priv = netdev_priv(soft_iface); const struct hard_iface *hard_iface; /* 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(hard_iface, &hardif_list, list) { if ((hard_iface->if_status != IF_ACTIVE) && (hard_iface->if_status != IF_TO_BE_ACTIVATED)) continue; if (hard_iface->soft_iface != soft_iface) continue; min_mtu = min_t(int, hard_iface->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 hard_iface *hard_iface) { struct bat_priv *bat_priv; struct hard_iface *primary_if = NULL; if (hard_iface->if_status != IF_INACTIVE) goto out; bat_priv = netdev_priv(hard_iface->soft_iface); bat_priv->bat_algo_ops->bat_ogm_update_mac(hard_iface); hard_iface->if_status = IF_TO_BE_ACTIVATED; /** * the first active interface becomes our primary interface or * the next active interface after the old primary interface was removed */ primary_if = primary_if_get_selected(bat_priv); if (!primary_if) primary_if_select(bat_priv, hard_iface); bat_info(hard_iface->soft_iface, "Interface activated: %s\n", hard_iface->net_dev->name); update_min_mtu(hard_iface->soft_iface); out: if (primary_if) hardif_free_ref(primary_if); } static void hardif_deactivate_interface(struct hard_iface *hard_iface) { if ((hard_iface->if_status != IF_ACTIVE) && (hard_iface->if_status != IF_TO_BE_ACTIVATED)) return; hard_iface->if_status = IF_INACTIVE; bat_info(hard_iface->soft_iface, "Interface deactivated: %s\n", hard_iface->net_dev->name); update_min_mtu(hard_iface->soft_iface); } int hardif_enable_interface(struct hard_iface *hard_iface, const char *iface_name) { struct bat_priv *bat_priv; struct net_device *soft_iface; int ret; if (hard_iface->if_status != IF_NOT_IN_USE) goto out; if (!atomic_inc_not_zero(&hard_iface->refcount)) goto out; /* hard-interface is part of a bridge */ if (hard_iface->net_dev->priv_flags & IFF_BRIDGE_PORT) pr_err("You are about to enable batman-adv on '%s' which already is part of a bridge. Unless you know exactly what you are doing this is probably wrong and won't work the way you think it would.\n", hard_iface->net_dev->name); soft_iface = dev_get_by_name(&init_net, iface_name); if (!soft_iface) { soft_iface = softif_create(iface_name); if (!soft_iface) { ret = -ENOMEM; goto err; } /* dev_get_by_name() increases the reference counter for us */ dev_hold(soft_iface); } if (!softif_is_valid(soft_iface)) { pr_err("Can't create batman mesh interface %s: already exists as regular interface\n", soft_iface->name); dev_put(soft_iface); ret = -EINVAL; goto err; } hard_iface->soft_iface = soft_iface; bat_priv = netdev_priv(hard_iface->soft_iface); bat_priv->bat_algo_ops->bat_ogm_init(hard_iface); if (!hard_iface->packet_buff) { bat_err(hard_iface->soft_iface, "Can't add interface packet (%s): out of memory\n", hard_iface->net_dev->name); ret = -ENOMEM; goto err; } hard_iface->if_num = bat_priv->num_ifaces; bat_priv->num_ifaces++; hard_iface->if_status = IF_INACTIVE; orig_hash_add_if(hard_iface, bat_priv->num_ifaces); hard_iface->batman_adv_ptype.type = __constant_htons(ETH_P_BATMAN); hard_iface->batman_adv_ptype.func = batman_skb_recv; hard_iface->batman_adv_ptype.dev = hard_iface->net_dev; dev_add_pack(&hard_iface->batman_adv_ptype); atomic_set(&hard_iface->seqno, 1); atomic_set(&hard_iface->frag_seqno, 1); bat_info(hard_iface->soft_iface, "Adding interface: %s\n", hard_iface->net_dev->name); if (atomic_read(&bat_priv->fragmentation) && hard_iface->net_dev->mtu < ETH_DATA_LEN + BAT_HEADER_LEN) bat_info(hard_iface->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", hard_iface->net_dev->name, hard_iface->net_dev->mtu, ETH_DATA_LEN + BAT_HEADER_LEN); if (!atomic_read(&bat_priv->fragmentation) && hard_iface->net_dev->mtu < ETH_DATA_LEN + BAT_HEADER_LEN) bat_info(hard_iface->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", hard_iface->net_dev->name, hard_iface->net_dev->mtu, ETH_DATA_LEN + BAT_HEADER_LEN); if (hardif_is_iface_up(hard_iface)) hardif_activate_interface(hard_iface); else bat_err(hard_iface->soft_iface, "Not using interface %s (retrying later): interface not active\n", hard_iface->net_dev->name); /* begin scheduling originator messages on that interface */ schedule_bat_ogm(hard_iface); out: return 0; err: hardif_free_ref(hard_iface); return ret; } void hardif_disable_interface(struct hard_iface *hard_iface) { struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface); struct hard_iface *primary_if = NULL; if (hard_iface->if_status == IF_ACTIVE) hardif_deactivate_interface(hard_iface); if (hard_iface->if_status != IF_INACTIVE) goto out; bat_info(hard_iface->soft_iface, "Removing interface: %s\n", hard_iface->net_dev->name); dev_remove_pack(&hard_iface->batman_adv_ptype); bat_priv->num_ifaces--; orig_hash_del_if(hard_iface, bat_priv->num_ifaces); primary_if = primary_if_get_selected(bat_priv); if (hard_iface == primary_if) { struct hard_iface *new_if; new_if = hardif_get_active(hard_iface->soft_iface); primary_if_select(bat_priv, new_if); if (new_if) hardif_free_ref(new_if); } kfree(hard_iface->packet_buff); hard_iface->packet_buff = NULL; hard_iface->if_status = IF_NOT_IN_USE; /* delete all references to this hard_iface */ purge_orig_ref(bat_priv); purge_outstanding_packets(bat_priv, hard_iface); dev_put(hard_iface->soft_iface); /* nobody uses this interface anymore */ if (!bat_priv->num_ifaces) softif_destroy(hard_iface->soft_iface); hard_iface->soft_iface = NULL; hardif_free_ref(hard_iface); out: if (primary_if) hardif_free_ref(primary_if); } static struct hard_iface *hardif_add_interface(struct net_device *net_dev) { struct hard_iface *hard_iface; int ret; ASSERT_RTNL(); ret = is_valid_iface(net_dev); if (ret != 1) goto out; dev_hold(net_dev); hard_iface = kmalloc(sizeof(*hard_iface), GFP_ATOMIC); if (!hard_iface) goto release_dev; ret = sysfs_add_hardif(&hard_iface->hardif_obj, net_dev); if (ret) goto free_if; hard_iface->if_num = -1; hard_iface->net_dev = net_dev; hard_iface->soft_iface = NULL; hard_iface->if_status = IF_NOT_IN_USE; INIT_LIST_HEAD(&hard_iface->list); /* extra reference for return */ atomic_set(&hard_iface->refcount, 2); check_known_mac_addr(hard_iface->net_dev); list_add_tail_rcu(&hard_iface->list, &hardif_list); return hard_iface; free_if: kfree(hard_iface); release_dev: dev_put(net_dev); out: return NULL; } static void hardif_remove_interface(struct hard_iface *hard_iface) { ASSERT_RTNL(); /* first deactivate interface */ if (hard_iface->if_status != IF_NOT_IN_USE) hardif_disable_interface(hard_iface); if (hard_iface->if_status != IF_NOT_IN_USE) return; hard_iface->if_status = IF_TO_BE_REMOVED; sysfs_del_hardif(&hard_iface->hardif_obj); hardif_free_ref(hard_iface); } void hardif_remove_interfaces(void) { struct hard_iface *hard_iface, *hard_iface_tmp; rtnl_lock(); list_for_each_entry_safe(hard_iface, hard_iface_tmp, &hardif_list, list) { list_del_rcu(&hard_iface->list); hardif_remove_interface(hard_iface); } rtnl_unlock(); } static int hard_if_event(struct notifier_block *this, unsigned long event, void *ptr) { struct net_device *net_dev = ptr; struct hard_iface *hard_iface = hardif_get_by_netdev(net_dev); struct hard_iface *primary_if = NULL; struct bat_priv *bat_priv; if (!hard_iface && event == NETDEV_REGISTER) hard_iface = hardif_add_interface(net_dev); if (!hard_iface) goto out; switch (event) { case NETDEV_UP: hardif_activate_interface(hard_iface); break; case NETDEV_GOING_DOWN: case NETDEV_DOWN: hardif_deactivate_interface(hard_iface); break; case NETDEV_UNREGISTER: list_del_rcu(&hard_iface->list); hardif_remove_interface(hard_iface); break; case NETDEV_CHANGEMTU: if (hard_iface->soft_iface) update_min_mtu(hard_iface->soft_iface); break; case NETDEV_CHANGEADDR: if (hard_iface->if_status == IF_NOT_IN_USE) goto hardif_put; check_known_mac_addr(hard_iface->net_dev); bat_priv = netdev_priv(hard_iface->soft_iface); bat_priv->bat_algo_ops->bat_ogm_update_mac(hard_iface); primary_if = primary_if_get_selected(bat_priv); if (!primary_if) goto hardif_put; if (hard_iface == primary_if) primary_if_update_addr(bat_priv); break; default: break; } hardif_put: hardif_free_ref(hard_iface); out: if (primary_if) hardif_free_ref(primary_if); return NOTIFY_DONE; } /* incoming packets with the batman ethertype received on any active hard * interface */ static 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_ogm_packet *batman_ogm_packet; struct hard_iface *hard_iface; int ret; hard_iface = container_of(ptype, struct hard_iface, 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 (!hard_iface->soft_iface) goto err_free; bat_priv = netdev_priv(hard_iface->soft_iface); if (atomic_read(&bat_priv->mesh_state) != MESH_ACTIVE) goto err_free; /* discard frames on not active interfaces */ if (hard_iface->if_status != IF_ACTIVE) goto err_free; batman_ogm_packet = (struct batman_ogm_packet *)skb->data; if (batman_ogm_packet->header.version != COMPAT_VERSION) { bat_dbg(DBG_BATMAN, bat_priv, "Drop packet: incompatible batman version (%i)\n", batman_ogm_packet->header.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_ogm_packet->header.packet_type) { /* batman originator packet */ case BAT_OGM: ret = recv_bat_ogm_packet(skb, hard_iface); break; /* batman icmp packet */ case BAT_ICMP: ret = recv_icmp_packet(skb, hard_iface); break; /* unicast packet */ case BAT_UNICAST: ret = recv_unicast_packet(skb, hard_iface); break; /* fragmented unicast packet */ case BAT_UNICAST_FRAG: ret = recv_ucast_frag_packet(skb, hard_iface); break; /* broadcast packet */ case BAT_BCAST: ret = recv_bcast_packet(skb, hard_iface); break; /* vis packet */ case BAT_VIS: ret = recv_vis_packet(skb, hard_iface); break; /* Translation table query (request or response) */ case BAT_TT_QUERY: ret = recv_tt_query(skb, hard_iface); break; /* Roaming advertisement */ case BAT_ROAM_ADV: ret = recv_roam_adv(skb, hard_iface); 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; } /* This function returns true if the interface represented by ifindex is a * 802.11 wireless device */ bool is_wifi_iface(int ifindex) { struct net_device *net_device = NULL; bool ret = false; if (ifindex == NULL_IFINDEX) goto out; net_device = dev_get_by_index(&init_net, ifindex); if (!net_device) goto out; #ifdef CONFIG_WIRELESS_EXT /* pre-cfg80211 drivers have to implement WEXT, so it is possible to * check for wireless_handlers != NULL */ if (net_device->wireless_handlers) ret = true; else #endif /* cfg80211 drivers have to set ieee80211_ptr */ if (net_device->ieee80211_ptr) ret = true; out: if (net_device) dev_put(net_device); return ret; } struct notifier_block hard_if_notifier = { .notifier_call = hard_if_event, };