[mirror_ubuntu-zesty-kernel.git] / net / batman-adv / gateway_common.c

/* Copyright (C) 2009-2016  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_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;
	}
}

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);
}
Commit	Line	Data
0046b040	1	/* Copyright (C) 2009-2016 B.A.T.M.A.N. contributors:
c6c8fea2 SE	2	*
	3	* Marek Lindner
	4	*
	5	* This program is free software; you can redistribute it and/or
	6	* modify it under the terms of version 2 of the GNU General Public
	7	* License as published by the Free Software Foundation.
	8	*
	9	* This program is distributed in the hope that it will be useful, but
	10	* WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	12	* General Public License for more details.
	13	*
	14	* You should have received a copy of the GNU General Public License
ebf38fb7	15	* along with this program; if not, see <http://www.gnu.org/licenses/>.
c6c8fea2 SE	16	*/
c6c8fea2 SE	17
c6c8fea2	18	#include "gateway_common.h"
1e2c2a4f SE	19	#include "main.h"
	20
	21	#include <linux/atomic.h>
77927b7d	22	#include <linux/errno.h>
1e2c2a4f SE	23	#include <linux/byteorder/generic.h>
1e2c2a4f SE	24	#include <linux/kernel.h>
0b8336f5	25	#include <linux/math64.h>
1e2c2a4f SE	26	#include <linux/netdevice.h>
	27	#include <linux/stddef.h>
	28	#include <linux/string.h>
	29
c6c8fea2	30	#include "gateway_client.h"
1e2c2a4f	31	#include "packet.h"
c6c8fea2	32
414254e3	33	/**
d737ccbe SE	34	* batadv_parse_throughput - parse supplied string buffer to extract throughput
d737ccbe SE	35	* information
414254e3 ML	36	* @net_dev: the soft interface net device
414254e3 ML	37	* @buff: string buffer to parse
d737ccbe SE	38	* @description: text shown when throughput string cannot be parsed
d737ccbe SE	39	* @throughput: pointer holding the returned throughput information
414254e3	40	*
62fe710f	41	* Return: false on parse error and true otherwise.
414254e3	42	*/
0b5ecc68 AQ	43	bool batadv_parse_throughput(struct net_device net_dev, char buff,
0b5ecc68 AQ	44	const char description, u32 throughput)
c6c8fea2	45	{
414254e3	46	enum batadv_bandwidth_units bw_unit_type = BATADV_BW_UNIT_KBIT;
d737ccbe SE	47	u64 lthroughput;
d737ccbe SE	48	char *tmp_ptr;
414254e3	49	int ret;
c6c8fea2	50
c6c8fea2 SE	51	if (strlen(buff) > 4) {
	52	tmp_ptr = buff + strlen(buff) - 4;
	53
b7a8d756	54	if (strncasecmp(tmp_ptr, "mbit", 4) == 0)
414254e3	55	bw_unit_type = BATADV_BW_UNIT_MBIT;
c6c8fea2	56
b7a8d756	57	if ((strncasecmp(tmp_ptr, "kbit", 4) == 0) \|\|
414254e3	58	(bw_unit_type == BATADV_BW_UNIT_MBIT))
c6c8fea2 SE	59	*tmp_ptr = '\0';
	60	}
	61
d737ccbe	62	ret = kstrtou64(buff, 10, &lthroughput);
c6c8fea2	63	if (ret) {
3e34819e	64	batadv_err(net_dev,
d737ccbe SE	65	"Invalid throughput speed for %s: %s\n",
d737ccbe SE	66	description, buff);
c6c8fea2 SE	67	return false;
	68	}
	69
414254e3 ML	70	switch (bw_unit_type) {
414254e3 ML	71	case BATADV_BW_UNIT_MBIT:
0b8336f5	72	/* prevent overflow */
d737ccbe	73	if (U64_MAX / 10 < lthroughput) {
0b8336f5	74	batadv_err(net_dev,
d737ccbe SE	75	"Throughput speed for %s too large: %s\n",
d737ccbe SE	76	description, buff);
0b8336f5 SE	77	return false;
	78	}
	79
d737ccbe	80	lthroughput *= 10;
414254e3 ML	81	break;
	82	case BATADV_BW_UNIT_KBIT:
	83	default:
d737ccbe	84	lthroughput = div_u64(lthroughput, 100);
414254e3 ML	85	break;
414254e3 ML	86	}
c6c8fea2	87
d737ccbe	88	if (lthroughput > U32_MAX) {
0b8336f5	89	batadv_err(net_dev,
d737ccbe SE	90	"Throughput speed for %s too large: %s\n",
d737ccbe SE	91	description, buff);
0b8336f5 SE	92	return false;
	93	}
	94
d737ccbe	95	*throughput = lthroughput;
0b8336f5	96
d737ccbe SE	97	return true;
d737ccbe SE	98	}
c6c8fea2	99
d737ccbe SE	100	/**
	101	* batadv_parse_gw_bandwidth - parse supplied string buffer to extract download
	102	* and upload bandwidth information
	103	* @net_dev: the soft interface net device
	104	* @buff: string buffer to parse
	105	* @down: pointer holding the returned download bandwidth information
	106	* @up: pointer holding the returned upload bandwidth information
	107	*
	108	* Return: false on parse error and true otherwise.
	109	*/
	110	static bool batadv_parse_gw_bandwidth(struct net_device net_dev, char buff,
	111	u32 down, u32 up)
	112	{
	113	char *slash_ptr;
	114	bool ret;
c6c8fea2	115
d737ccbe SE	116	slash_ptr = strchr(buff, '/');
	117	if (slash_ptr)
	118	*slash_ptr = 0;
c6c8fea2	119
d737ccbe SE	120	ret = batadv_parse_throughput(net_dev, buff, "download gateway speed",
	121	down);
	122	if (!ret)
	123	return false;
0b8336f5	124
d737ccbe SE	125	/* we also got some upload info */
	126	if (slash_ptr) {
	127	ret = batadv_parse_throughput(net_dev, slash_ptr + 1,
	128	"upload gateway speed", up);
	129	if (!ret)
0b8336f5	130	return false;
c6c8fea2 SE	131	}
	132
	133	return true;
	134	}
	135
414254e3 ML	136	/**
	137	* batadv_gw_tvlv_container_update - update the gw tvlv container after gateway
	138	* setting change
	139	* @bat_priv: the bat priv with all the soft interface information
	140	*/
	141	void batadv_gw_tvlv_container_update(struct batadv_priv *bat_priv)
	142	{
	143	struct batadv_tvlv_gateway_data gw;
6b5e971a	144	u32 down, up;
414254e3 ML	145	char gw_mode;
	146
	147	gw_mode = atomic_read(&bat_priv->gw_mode);
	148
	149	switch (gw_mode) {
	150	case BATADV_GW_MODE_OFF:
	151	case BATADV_GW_MODE_CLIENT:
	152	batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1);
	153	break;
	154	case BATADV_GW_MODE_SERVER:
	155	down = atomic_read(&bat_priv->gw.bandwidth_down);
	156	up = atomic_read(&bat_priv->gw.bandwidth_up);
	157	gw.bandwidth_down = htonl(down);
	158	gw.bandwidth_up = htonl(up);
	159	batadv_tvlv_container_register(bat_priv, BATADV_TVLV_GW, 1,
	160	&gw, sizeof(gw));
	161	break;
	162	}
	163	}
	164
84d5e5e0 SE	165	ssize_t batadv_gw_bandwidth_set(struct net_device net_dev, char buff,
84d5e5e0 SE	166	size_t count)
c6c8fea2	167	{
56303d34	168	struct batadv_priv *bat_priv = netdev_priv(net_dev);
4f248cff SE	169	u32 down_curr;
	170	u32 up_curr;
	171	u32 down_new = 0;
	172	u32 up_new = 0;
c6c8fea2 SE	173	bool ret;
c6c8fea2 SE	174
414254e3 ML	175	down_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_down);
	176	up_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_up);
	177
	178	ret = batadv_parse_gw_bandwidth(net_dev, buff, &down_new, &up_new);
c6c8fea2	179	if (!ret)
77927b7d	180	return -EINVAL;
c6c8fea2	181
414254e3 ML	182	if (!down_new)
414254e3 ML	183	down_new = 1;
c6c8fea2	184
414254e3 ML	185	if (!up_new)
414254e3 ML	186	up_new = down_new / 5;
c6c8fea2	187
414254e3 ML	188	if (!up_new)
414254e3 ML	189	up_new = 1;
c6c8fea2	190
414254e3	191	if ((down_curr == down_new) && (up_curr == up_new))
dafe94b2 ML	192	return count;
dafe94b2 ML	193
4e820e72	194	batadv_gw_reselect(bat_priv);
3e34819e	195	batadv_info(net_dev,
414254e3 ML	196	"Changing gateway bandwidth from: '%u.%u/%u.%u MBit' to: '%u.%u/%u.%u MBit'\n",
	197	down_curr / 10, down_curr % 10, up_curr / 10, up_curr % 10,
	198	down_new / 10, down_new % 10, up_new / 10, up_new % 10);
c6c8fea2	199
414254e3 ML	200	atomic_set(&bat_priv->gw.bandwidth_down, down_new);
	201	atomic_set(&bat_priv->gw.bandwidth_up, up_new);
	202	batadv_gw_tvlv_container_update(bat_priv);
c6c8fea2	203
c6c8fea2 SE	204	return count;
c6c8fea2 SE	205	}
414254e3 ML	206
	207	/**
	208	* batadv_gw_tvlv_ogm_handler_v1 - process incoming gateway tvlv container
	209	* @bat_priv: the bat priv with all the soft interface information
	210	* @orig: the orig_node of the ogm
	211	* @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
	212	* @tvlv_value: tvlv buffer containing the gateway data
	213	* @tvlv_value_len: tvlv buffer length
	214	*/
	215	static void batadv_gw_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
	216	struct batadv_orig_node *orig,
6b5e971a SE	217	u8 flags,
6b5e971a SE	218	void *tvlv_value, u16 tvlv_value_len)
414254e3 ML	219	{
	220	struct batadv_tvlv_gateway_data gateway, *gateway_ptr;
	221
	222	/* only fetch the tvlv value if the handler wasn't called via the
	223	* CIFNOTFND flag and if there is data to fetch
	224	*/
	225	if ((flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND) \|\|
	226	(tvlv_value_len < sizeof(gateway))) {
	227	gateway.bandwidth_down = 0;
	228	gateway.bandwidth_up = 0;
	229	} else {
	230	gateway_ptr = tvlv_value;
	231	gateway.bandwidth_down = gateway_ptr->bandwidth_down;
	232	gateway.bandwidth_up = gateway_ptr->bandwidth_up;
	233	if ((gateway.bandwidth_down == 0) \|\|
	234	(gateway.bandwidth_up == 0)) {
	235	gateway.bandwidth_down = 0;
	236	gateway.bandwidth_up = 0;
	237	}
	238	}
	239
	240	batadv_gw_node_update(bat_priv, orig, &gateway);
	241
	242	/* restart gateway selection if fast or late switching was enabled */
	243	if ((gateway.bandwidth_down != 0) &&
	244	(atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_CLIENT) &&
	245	(atomic_read(&bat_priv->gw_sel_class) > 2))
	246	batadv_gw_check_election(bat_priv, orig);
	247	}
	248
	249	/**
	250	* batadv_gw_init - initialise the gateway handling internals
	251	* @bat_priv: the bat priv with all the soft interface information
	252	*/
	253	void batadv_gw_init(struct batadv_priv *bat_priv)
	254	{
	255	batadv_tvlv_handler_register(bat_priv, batadv_gw_tvlv_ogm_handler_v1,
	256	NULL, BATADV_TVLV_GW, 1,
	257	BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
	258	}
	259
	260	/**
	261	* batadv_gw_free - free the gateway handling internals
	262	* @bat_priv: the bat priv with all the soft interface information
	263	*/
	264	void batadv_gw_free(struct batadv_priv *bat_priv)
	265	{
	266	batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1);
	267	batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_GW, 1);
	268	}