path: root/net/batman-adv/soft-interface.c

// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) B.A.T.M.A.N. contributors:
 *
 * Marek Lindner, Simon Wunderlich
 */

#include "soft-interface.h"
#include "main.h"

#include <linux/atomic.h>
#include <linux/byteorder/generic.h>
#include <linux/cache.h>
#include <linux/compiler.h>
#include <linux/container_of.h>
#include <linux/cpumask.h>
#include <linux/errno.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/gfp.h>
#include <linux/if_ether.h>
#include <linux/if_vlan.h>
#include <linux/jiffies.h>
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/lockdep.h>
#include <linux/netdevice.h>
#include <linux/netlink.h>
#include <linux/percpu.h>
#include <linux/random.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/socket.h>
#include <linux/spinlock.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <linux/types.h>
#include <net/net_namespace.h>
#include <net/netlink.h>
#include <uapi/linux/batadv_packet.h>
#include <uapi/linux/batman_adv.h>

#include "bat_algo.h"
#include "bridge_loop_avoidance.h"
#include "distributed-arp-table.h"
#include "gateway_client.h"
#include "hard-interface.h"
#include "multicast.h"
#include "network-coding.h"
#include "send.h"
#include "translation-table.h"

/**
 * batadv_skb_head_push() - Increase header size and move (push) head pointer
 * @skb: packet buffer which should be modified
 * @len: number of bytes to add
 *
 * Return: 0 on success or negative error number in case of failure
 */
int batadv_skb_head_push(struct sk_buff *skb, unsigned int len)
{
	int result;

	/* TODO: We must check if we can release all references to non-payload
	 * data using __skb_header_release in our skbs to allow skb_cow_header
	 * to work optimally. This means that those skbs are not allowed to read
	 * or write any data which is before the current position of skb->data
	 * after that call and thus allow other skbs with the same data buffer
	 * to write freely in that area.
	 */
	result = skb_cow_head(skb, len);
	if (result < 0)
		return result;

	skb_push(skb, len);
	return 0;
}

static int batadv_interface_open(struct net_device *dev)
{
	netif_start_queue(dev);
	return 0;
}

static int batadv_interface_release(struct net_device *dev)
{
	netif_stop_queue(dev);
	return 0;
}

/**
 * batadv_sum_counter() - Sum the cpu-local counters for index 'idx'
 * @bat_priv: the bat priv with all the soft interface information
 * @idx: index of counter to sum up
 *
 * Return: sum of all cpu-local counters
 */
static u64 batadv_sum_counter(struct batadv_priv *bat_priv,  size_t idx)
{
	u64 *counters, sum = 0;
	int cpu;

	for_each_possible_cpu(cpu) {
		counters = per_cpu_ptr(bat_priv->bat_counters, cpu);
		sum += counters[idx];
	}

	return sum;
}

static struct net_device_stats *batadv_interface_stats(struct net_device *dev)
{
	struct batadv_priv *bat_priv = netdev_priv(dev);
	struct net_device_stats *stats = &dev->stats;

	stats->tx_packets = batadv_sum_counter(bat_priv, BATADV_CNT_TX);
	stats->tx_bytes = batadv_sum_counter(bat_priv, BATADV_CNT_TX_BYTES);
	stats->tx_dropped = batadv_sum_counter(bat_priv, BATADV_CNT_TX_DROPPED);
	stats->rx_packets = batadv_sum_counter(bat_priv, BATADV_CNT_RX);
	stats->rx_bytes = batadv_sum_counter(bat_priv, BATADV_CNT_RX_BYTES);
	return stats;
}

static int batadv_interface_set_mac_addr(struct net_device *dev, void *p)
{
	struct batadv_priv *bat_priv = netdev_priv(dev);
	struct batadv_softif_vlan *vlan;
	struct sockaddr *addr = p;
	u8 old_addr[ETH_ALEN];

	if (!is_valid_ether_addr(addr->sa_data))
		return -EADDRNOTAVAIL;

	ether_addr_copy(old_addr, dev->dev_addr);
	eth_hw_addr_set(dev, addr->sa_data);

	/* only modify transtable if it has been initialized before */
	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
		return 0;

	rcu_read_lock();
	hlist_for_each_entry_rcu(vlan, &bat_priv->softif_vlan_list, list) {
		batadv_tt_local_remove(bat_priv, old_addr, vlan->vid,
				       "mac address changed", false);
		batadv_tt_local_add(dev, addr->sa_data, vlan->vid,
				    BATADV_NULL_IFINDEX, BATADV_NO_MARK);
	}
	rcu_read_unlock();

	return 0;
}

static int batadv_interface_change_mtu(struct net_device *dev, int new_mtu)
{
	struct batadv_priv *bat_priv = netdev_priv(dev