diff options
Diffstat (limited to 'net/batman-adv/bat_v_elp.c')
| -rw-r--r-- | net/batman-adv/bat_v_elp.c | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/net/batman-adv/bat_v_elp.c b/net/batman-adv/bat_v_elp.c new file mode 100644 index 000000000000..bc6e046c614c --- /dev/null +++ b/net/batman-adv/bat_v_elp.c @@ -0,0 +1,193 @@ +/* Copyright (C) 2011-2016 B.A.T.M.A.N. contributors: + * + * Linus Lüssing, Marek Lindner + * + * 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, see <http://www.gnu.org/licenses/>. + */ + +#include "bat_v_elp.h" +#include "main.h" + +#include <linux/atomic.h> +#include <linux/byteorder/generic.h> +#include <linux/errno.h> +#include <linux/etherdevice.h> +#include <linux/fs.h> +#include <linux/if_ether.h> +#include <linux/jiffies.h> +#include <linux/kernel.h> +#include <linux/netdevice.h> +#include <linux/random.h> +#include <linux/rculist.h> +#include <linux/rcupdate.h> +#include <linux/skbuff.h> +#include <linux/stddef.h> +#include <linux/string.h> +#include <linux/types.h> +#include <linux/workqueue.h> + +#include "bat_algo.h" +#include "hard-interface.h" +#include "packet.h" +#include "send.h" + +/** + * batadv_v_elp_start_timer - restart timer for ELP periodic work + * @hard_iface: the interface for which the timer has to be reset + */ +static void batadv_v_elp_start_timer(struct batadv_hard_iface *hard_iface) +{ + unsigned int msecs; + + msecs = atomic_read(&hard_iface->bat_v.elp_interval) - BATADV_JITTER; + msecs += prandom_u32() % (2 * BATADV_JITTER); + + queue_delayed_work(batadv_event_workqueue, &hard_iface->bat_v.elp_wq, + msecs_to_jiffies(msecs)); +} + +/** + * batadv_v_elp_periodic_work - ELP periodic task per interface + * @work: work queue item + * + * Emits broadcast ELP message in regular intervals. + */ +static void batadv_v_elp_periodic_work(struct work_struct *work) +{ + struct batadv_hard_iface *hard_iface; + struct batadv_hard_iface_bat_v *bat_v; + struct batadv_elp_packet *elp_packet; + struct batadv_priv *bat_priv; + struct sk_buff *skb; + u32 elp_interval; + + bat_v = container_of(work, struct batadv_hard_iface_bat_v, elp_wq.work); + hard_iface = container_of(bat_v, struct batadv_hard_iface, bat_v); + bat_priv = netdev_priv(hard_iface->soft_iface); + + if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) + goto out; + + /* we are in the process of shutting this interface down */ + if ((hard_iface->if_status == BATADV_IF_NOT_IN_USE) || + (hard_iface->if_status == BATADV_IF_TO_BE_REMOVED)) + goto out; + + /* the interface was enabled but may not be ready yet */ + if (hard_iface->if_status != BATADV_IF_ACTIVE) + goto restart_timer; + + skb = skb_copy(hard_iface->bat_v.elp_skb, GFP_ATOMIC); + if (!skb) + goto restart_timer; + + elp_packet = (struct batadv_elp_packet *)skb->data; + elp_packet->seqno = htonl(atomic_read(&hard_iface->bat_v.elp_seqno)); + elp_interval = atomic_read(&hard_iface->bat_v.elp_interval); + elp_packet->elp_interval = htonl(elp_interval); + + batadv_dbg(BATADV_DBG_BATMAN, bat_priv, + "Sending broadcast ELP packet on interface %s, seqno %u\n", + hard_iface->net_dev->name, + atomic_read(&hard_iface->bat_v.elp_seqno)); + + batadv_send_skb_packet(skb, hard_iface, batadv_broadcast_addr); + + atomic_inc(&hard_iface->bat_v.elp_seqno); + +restart_timer: + batadv_v_elp_start_timer(hard_iface); +out: + return; +} + +/** + * batadv_v_elp_iface_enable - setup the ELP interface private resources + * @hard_iface: interface for which the data has to be prepared + * + * Return: 0 on success or a -ENOMEM in case of failure. + */ +int batadv_v_elp_iface_enable(struct batadv_hard_iface *hard_iface) +{ + struct batadv_elp_packet *elp_packet; + unsigned char *elp_buff; + u32 random_seqno; + size_t size; + int res = -ENOMEM; + + size = ETH_HLEN + NET_IP_ALIGN + BATADV_ELP_HLEN; + hard_iface->bat_v.elp_skb = dev_alloc_skb(size); + if (!hard_iface->bat_v.elp_skb) + goto out; + + skb_reserve(hard_iface->bat_v.elp_skb, ETH_HLEN + NET_IP_ALIGN); + elp_buff = skb_push(hard_iface->bat_v.elp_skb, BATADV_ELP_HLEN); + elp_packet = (struct batadv_elp_packet *)elp_buff; + memset(elp_packet, 0, BATADV_ELP_HLEN); + + elp_packet->packet_type = BATADV_ELP; + elp_packet->version = BATADV_COMPAT_VERSION; + + /* randomize initial seqno to avoid collision */ + get_random_bytes(&random_seqno, sizeof(random_seqno)); + atomic_set(&hard_iface->bat_v.elp_seqno, random_seqno); + atomic_set(&hard_iface->bat_v.elp_interval, 500); + + INIT_DELAYED_WORK(&hard_iface->bat_v.elp_wq, + batadv_v_elp_periodic_work); + batadv_v_elp_start_timer(hard_iface); + res = 0; + +out: + return res; +} + +/** + * batadv_v_elp_iface_disable - release ELP interface private resources + * @hard_iface: interface for which the resources have to be released + */ +void batadv_v_elp_iface_disable(struct batadv_hard_iface *hard_iface) +{ + cancel_delayed_work_sync(&hard_iface->bat_v.elp_wq); + + dev_kfree_skb(hard_iface->bat_v.elp_skb); + hard_iface->bat_v.elp_skb = NULL; +} + +/** + * batadv_v_elp_primary_iface_set - change internal data to reflect the new + * primary interface + * @primary_iface: the new primary interface + */ +void batadv_v_elp_primary_iface_set(struct batadv_hard_iface *primary_iface) +{ + struct batadv_hard_iface *hard_iface; + struct batadv_elp_packet *elp_packet; + struct sk_buff *skb; + + /* update orig field of every elp iface belonging to this mesh */ + rcu_read_lock(); + list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) { + if (primary_iface->soft_iface != hard_iface->soft_iface) + continue; + + if (!hard_iface->bat_v.elp_skb) + continue; + + skb = hard_iface->bat_v.elp_skb; + elp_packet = (struct batadv_elp_packet *)skb->data; + ether_addr_copy(elp_packet->orig, + primary_iface->net_dev->dev_addr); + } + rcu_read_unlock(); +} |