linux/net/batman-adv/gateway_common.c

286 lines
7.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2009-2019 B.A.T.M.A.N. contributors:
*
* 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 "gateway_common.h"
#include "main.h"
#include <linux/atomic.h>
#include <linux/byteorder/generic.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/math64.h>
#include <linux/netdevice.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <uapi/linux/batadv_packet.h>
#include <uapi/linux/batman_adv.h>
#include "gateway_client.h"
#include "log.h"
#include "tvlv.h"
/**
* batadv_parse_throughput() - parse supplied string buffer to extract
* throughput information
* @net_dev: the soft interface net device
* @buff: string buffer to parse
* @description: text shown when throughput string cannot be parsed
* @throughput: pointer holding the returned throughput information
*
* Return: false on parse error and true otherwise.
*/
bool batadv_parse_throughput(struct net_device *net_dev, char *buff,
const char *description, u32 *throughput)
{
enum batadv_bandwidth_units bw_unit_type = BATADV_BW_UNIT_KBIT;
u64 lthroughput;
char *tmp_ptr;
int ret;
if (strlen(buff) > 4) {
tmp_ptr = buff + strlen(buff) - 4;
if (strncasecmp(tmp_ptr, "mbit", 4) == 0)
bw_unit_type = BATADV_BW_UNIT_MBIT;
if (strncasecmp(tmp_ptr, "kbit", 4) == 0 ||
bw_unit_type == BATADV_BW_UNIT_MBIT)
*tmp_ptr = '\0';
}
ret = kstrtou64(buff, 10, &lthroughput);
if (ret) {
batadv_err(net_dev,
"Invalid throughput speed for %s: %s\n",
description, buff);
return false;
}
switch (bw_unit_type) {
case BATADV_BW_UNIT_MBIT:
/* prevent overflow */
if (U64_MAX / 10 < lthroughput) {
batadv_err(net_dev,
"Throughput speed for %s too large: %s\n",
description, buff);
return false;
}
lthroughput *= 10;
break;
case BATADV_BW_UNIT_KBIT:
default:
lthroughput = div_u64(lthroughput, 100);
break;
}
if (lthroughput > U32_MAX) {
batadv_err(net_dev,
"Throughput speed for %s too large: %s\n",
description, buff);
return false;
}
*throughput = lthroughput;
return true;
}
/**
* batadv_parse_gw_bandwidth() - parse supplied string buffer to extract
* download and upload bandwidth information
* @net_dev: the soft interface net device
* @buff: string buffer to parse
* @down: pointer holding the returned download bandwidth information
* @up: pointer holding the returned upload bandwidth information
*
* Return: false on parse error and true otherwise.
*/
static bool batadv_parse_gw_bandwidth(struct net_device *net_dev, char *buff,
u32 *down, u32 *up)
{
char *slash_ptr;
bool ret;
slash_ptr = strchr(buff, '/');
if (slash_ptr)
*slash_ptr = 0;
ret = batadv_parse_throughput(net_dev, buff, "download gateway speed",
down);
if (!ret)
return false;
/* we also got some upload info */
if (slash_ptr) {
ret = batadv_parse_throughput(net_dev, slash_ptr + 1,
"upload gateway speed", up);
if (!ret)
return false;
}
return true;
}
/**
* batadv_gw_tvlv_container_update() - update the gw tvlv container after
* gateway setting change
* @bat_priv: the bat priv with all the soft interface information
*/
void batadv_gw_tvlv_container_update(struct batadv_priv *bat_priv)
{
struct batadv_tvlv_gateway_data gw;
u32 down, up;
char gw_mode;
gw_mode = atomic_read(&bat_priv->gw.mode);
switch (gw_mode) {
case BATADV_GW_MODE_OFF:
case BATADV_GW_MODE_CLIENT:
batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1);
break;
case BATADV_GW_MODE_SERVER:
down = atomic_read(&bat_priv->gw.bandwidth_down);
up = atomic_read(&bat_priv->gw.bandwidth_up);
gw.bandwidth_down = htonl(down);
gw.bandwidth_up = htonl(up);
batadv_tvlv_container_register(bat_priv, BATADV_TVLV_GW, 1,
&gw, sizeof(gw));
break;
}
}
/**
* batadv_gw_bandwidth_set() - Parse and set download/upload gateway bandwidth
* from supplied string buffer
* @net_dev: netdev struct of the soft interface
* @buff: the buffer containing the user data
* @count: number of bytes in the buffer
*
* Return: 'count' on success or a negative error code in case of failure
*/
ssize_t batadv_gw_bandwidth_set(struct net_device *net_dev, char *buff,
size_t count)
{
struct batadv_priv *bat_priv = netdev_priv(net_dev);
u32 down_curr;
u32 up_curr;
u32 down_new = 0;
u32 up_new = 0;
bool ret;
down_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_down);
up_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_up);
ret = batadv_parse_gw_bandwidth(net_dev, buff, &down_new, &up_new);
if (!ret)
return -EINVAL;
if (!down_new)
down_new = 1;
if (!up_new)
up_new = down_new / 5;
if (!up_new)
up_new = 1;
if (down_curr == down_new && up_curr == up_new)
return count;
batadv_gw_reselect(bat_priv);
batadv_info(net_dev,
"Changing gateway bandwidth from: '%u.%u/%u.%u MBit' to: '%u.%u/%u.%u MBit'\n",
down_curr / 10, down_curr % 10, up_curr / 10, up_curr % 10,
down_new / 10, down_new % 10, up_new / 10, up_new % 10);
atomic_set(&bat_priv->gw.bandwidth_down, down_new);
atomic_set(&bat_priv->gw.bandwidth_up, up_new);
batadv_gw_tvlv_container_update(bat_priv);
return count;
}
/**
* batadv_gw_tvlv_ogm_handler_v1() - process incoming gateway tvlv container
* @bat_priv: the bat priv with all the soft interface information
* @orig: the orig_node of the ogm
* @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
* @tvlv_value: tvlv buffer containing the gateway data
* @tvlv_value_len: tvlv buffer length
*/
static void batadv_gw_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
struct batadv_orig_node *orig,
u8 flags,
void *tvlv_value, u16 tvlv_value_len)
{
struct batadv_tvlv_gateway_data gateway, *gateway_ptr;
/* only fetch the tvlv value if the handler wasn't called via the
* CIFNOTFND flag and if there is data to fetch
*/
if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND ||
tvlv_value_len < sizeof(gateway)) {
gateway.bandwidth_down = 0;
gateway.bandwidth_up = 0;
} else {
gateway_ptr = tvlv_value;
gateway.bandwidth_down = gateway_ptr->bandwidth_down;
gateway.bandwidth_up = gateway_ptr->bandwidth_up;
if (gateway.bandwidth_down == 0 ||
gateway.bandwidth_up == 0) {
gateway.bandwidth_down = 0;
gateway.bandwidth_up = 0;
}
}
batadv_gw_node_update(bat_priv, orig, &gateway);
/* restart gateway selection */
if (gateway.bandwidth_down != 0 &&
atomic_read(&bat_priv->gw.mode) == BATADV_GW_MODE_CLIENT)
batadv_gw_check_election(bat_priv, orig);
}
/**
* batadv_gw_init() - initialise the gateway handling internals
* @bat_priv: the bat priv with all the soft interface information
*/
void batadv_gw_init(struct batadv_priv *bat_priv)
{
if (bat_priv->algo_ops->gw.init_sel_class)
bat_priv->algo_ops->gw.init_sel_class(bat_priv);
else
atomic_set(&bat_priv->gw.sel_class, 1);
batadv_tvlv_handler_register(bat_priv, batadv_gw_tvlv_ogm_handler_v1,
NULL, BATADV_TVLV_GW, 1,
BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
}
/**
* batadv_gw_free() - free the gateway handling internals
* @bat_priv: the bat priv with all the soft interface information
*/
void batadv_gw_free(struct batadv_priv *bat_priv)
{
batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1);
batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_GW, 1);
}