/* Copyright (C) 2009-2015 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/errno.h>
#include <linux/byteorder/generic.h>
#include <linux/kernel.h>
#include <linux/math64.h>
#include <linux/netdevice.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include "gateway_client.h"
#include "packet.h"
/**
* 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
*
* Returns false on parse error and true otherwise.
*/
static bool batadv_parse_gw_bandwidth(struct net_device *net_dev, char *buff,
u32 *down, u32 *up)
{
enum batadv_bandwidth_units bw_unit_type = BATADV_BW_UNIT_KBIT;
char *slash_ptr, *tmp_ptr;
u64 ldown, lup;
int ret;
slash_ptr = strchr(buff, '/');
if (slash_ptr)
*slash_ptr = 0;
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, &ldown);
if (ret) {
batadv_err(net_dev,
"Download speed of gateway mode invalid: %s\n",
buff);
return false;
}
switch (bw_unit_type) {
case BATADV_BW_UNIT_MBIT:
/* prevent overflow */
if (U64_MAX / 10 < ldown) {
batadv_err(net_dev,
"Download speed of gateway mode too large: %s\n",
buff);
return false;
}
ldown *= 10;
break;
case BATADV_BW_UNIT_KBIT:
default:
ldown = div_u64(ldown, 100);
break;
}
if (U32_MAX < ldown) {
batadv_err(net_dev,
"Download speed of gateway mode too large: %s\n",
buff);
return false;
}
*down = ldown;
/* we also got some upload info */
if (slash_ptr) {
bw_unit_type = BATADV_BW_UNIT_KBIT;
if (strlen(slash_ptr + 1) > 4) {
tmp_ptr = slash_ptr + 1 - 4 + strlen(slash_ptr + 1);
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(slash_ptr + 1, 10, &lup);
if (ret) {
batadv_err(net_dev,
"Upload speed of gateway mode invalid: %s\n",
slash_ptr + 1);
return false;
}
switch (bw_unit_type) {
case BATADV_BW_UNIT_MBIT:
/* prevent overflow */
if (U64_MAX / 10 < lup) {
batadv_err(net_dev,
"Upload speed of gateway mode too large: %s\n",
slash_ptr + 1);
return false;
}
lup *= 10;
break;
case BATADV_BW_UNIT_KBIT:
default:
lup = div_u64(lup, 100);
break;
}
if (U32_MAX < lup) {
batadv_err(net_dev,
"Upload speed of gateway mode too large: %s\n",
slash_ptr + 1);
return false;
}
*up = lup;
}
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;
}
}
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 fast or late switching was enabled */
if ((gateway.bandwidth_down != 0) &&
(atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_CLIENT) &&
(atomic_read(&bat_priv->gw_sel_class) > 2))
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)
{
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);
}
