[deliverable/linux.git] / net / batman-adv / gateway_common.c

/* 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);
}
Commit	Line	Data
9f6446c7	1	/* Copyright (C) 2009-2015 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 ML	33	/**
	34	* batadv_parse_gw_bandwidth - parse supplied string buffer to extract download
	35	* and upload bandwidth information
	36	* @net_dev: the soft interface net device
	37	* @buff: string buffer to parse
	38	* @down: pointer holding the returned download bandwidth information
	39	* @up: pointer holding the returned upload bandwidth information
	40	*
	41	* Returns false on parse error and true otherwise.
	42	*/
8e714a5d	43	static bool batadv_parse_gw_bandwidth(struct net_device net_dev, char buff,
6b5e971a	44	u32 down, u32 up)
c6c8fea2	45	{
414254e3	46	enum batadv_bandwidth_units bw_unit_type = BATADV_BW_UNIT_KBIT;
c6c8fea2	47	char slash_ptr, tmp_ptr;
0b8336f5	48	u64 ldown, lup;
414254e3	49	int ret;
c6c8fea2 SE	50
	51	slash_ptr = strchr(buff, '/');
	52	if (slash_ptr)
	53	*slash_ptr = 0;
	54
	55	if (strlen(buff) > 4) {
	56	tmp_ptr = buff + strlen(buff) - 4;
	57
b7a8d756	58	if (strncasecmp(tmp_ptr, "mbit", 4) == 0)
414254e3	59	bw_unit_type = BATADV_BW_UNIT_MBIT;
c6c8fea2	60
b7a8d756	61	if ((strncasecmp(tmp_ptr, "kbit", 4) == 0) \|\|
414254e3	62	(bw_unit_type == BATADV_BW_UNIT_MBIT))
c6c8fea2 SE	63	*tmp_ptr = '\0';
	64	}
	65
0b8336f5	66	ret = kstrtou64(buff, 10, &ldown);
c6c8fea2	67	if (ret) {
3e34819e SE	68	batadv_err(net_dev,
	69	"Download speed of gateway mode invalid: %s\n",
	70	buff);
c6c8fea2 SE	71	return false;
	72	}
	73
414254e3 ML	74	switch (bw_unit_type) {
414254e3 ML	75	case BATADV_BW_UNIT_MBIT:
0b8336f5 SE	76	/* prevent overflow */
	77	if (U64_MAX / 10 < ldown) {
	78	batadv_err(net_dev,
	79	"Download speed of gateway mode too large: %s\n",
	80	buff);
	81	return false;
	82	}
	83
	84	ldown *= 10;
414254e3 ML	85	break;
	86	case BATADV_BW_UNIT_KBIT:
	87	default:
0b8336f5	88	ldown = div_u64(ldown, 100);
414254e3 ML	89	break;
414254e3 ML	90	}
c6c8fea2	91
0b8336f5 SE	92	if (U32_MAX < ldown) {
	93	batadv_err(net_dev,
	94	"Download speed of gateway mode too large: %s\n",
	95	buff);
	96	return false;
	97	}
	98
	99	*down = ldown;
	100
c6c8fea2 SE	101	/* we also got some upload info */
c6c8fea2 SE	102	if (slash_ptr) {
414254e3	103	bw_unit_type = BATADV_BW_UNIT_KBIT;
c6c8fea2 SE	104
	105	if (strlen(slash_ptr + 1) > 4) {
	106	tmp_ptr = slash_ptr + 1 - 4 + strlen(slash_ptr + 1);
	107
b7a8d756	108	if (strncasecmp(tmp_ptr, "mbit", 4) == 0)
414254e3	109	bw_unit_type = BATADV_BW_UNIT_MBIT;
c6c8fea2	110
b7a8d756	111	if ((strncasecmp(tmp_ptr, "kbit", 4) == 0) \|\|
414254e3	112	(bw_unit_type == BATADV_BW_UNIT_MBIT))
c6c8fea2 SE	113	*tmp_ptr = '\0';
	114	}
	115
0b8336f5	116	ret = kstrtou64(slash_ptr + 1, 10, &lup);
c6c8fea2	117	if (ret) {
3e34819e SE	118	batadv_err(net_dev,
	119	"Upload speed of gateway mode invalid: %s\n",
	120	slash_ptr + 1);
c6c8fea2 SE	121	return false;
	122	}
	123
414254e3 ML	124	switch (bw_unit_type) {
414254e3 ML	125	case BATADV_BW_UNIT_MBIT:
0b8336f5 SE	126	/* prevent overflow */
	127	if (U64_MAX / 10 < lup) {
	128	batadv_err(net_dev,
	129	"Upload speed of gateway mode too large: %s\n",
	130	slash_ptr + 1);
	131	return false;
	132	}
	133
	134	lup *= 10;
414254e3 ML	135	break;
	136	case BATADV_BW_UNIT_KBIT:
	137	default:
0b8336f5	138	lup = div_u64(lup, 100);
414254e3 ML	139	break;
414254e3 ML	140	}
0b8336f5 SE	141
	142	if (U32_MAX < lup) {
	143	batadv_err(net_dev,
	144	"Upload speed of gateway mode too large: %s\n",
	145	slash_ptr + 1);
	146	return false;
	147	}
	148
	149	*up = lup;
c6c8fea2 SE	150	}
	151
	152	return true;
	153	}
	154
414254e3 ML	155	/**
	156	* batadv_gw_tvlv_container_update - update the gw tvlv container after gateway
	157	* setting change
	158	* @bat_priv: the bat priv with all the soft interface information
	159	*/
	160	void batadv_gw_tvlv_container_update(struct batadv_priv *bat_priv)
	161	{
	162	struct batadv_tvlv_gateway_data gw;
6b5e971a	163	u32 down, up;
414254e3 ML	164	char gw_mode;
	165
	166	gw_mode = atomic_read(&bat_priv->gw_mode);
	167
	168	switch (gw_mode) {
	169	case BATADV_GW_MODE_OFF:
	170	case BATADV_GW_MODE_CLIENT:
	171	batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1);
	172	break;
	173	case BATADV_GW_MODE_SERVER:
	174	down = atomic_read(&bat_priv->gw.bandwidth_down);
	175	up = atomic_read(&bat_priv->gw.bandwidth_up);
	176	gw.bandwidth_down = htonl(down);
	177	gw.bandwidth_up = htonl(up);
	178	batadv_tvlv_container_register(bat_priv, BATADV_TVLV_GW, 1,
	179	&gw, sizeof(gw));
	180	break;
	181	}
	182	}
	183
84d5e5e0 SE	184	ssize_t batadv_gw_bandwidth_set(struct net_device net_dev, char buff,
84d5e5e0 SE	185	size_t count)
c6c8fea2	186	{
56303d34	187	struct batadv_priv *bat_priv = netdev_priv(net_dev);
4f248cff SE	188	u32 down_curr;
	189	u32 up_curr;
	190	u32 down_new = 0;
	191	u32 up_new = 0;
c6c8fea2 SE	192	bool ret;
c6c8fea2 SE	193
414254e3 ML	194	down_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_down);
	195	up_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_up);
	196
	197	ret = batadv_parse_gw_bandwidth(net_dev, buff, &down_new, &up_new);
c6c8fea2	198	if (!ret)
77927b7d	199	return -EINVAL;
c6c8fea2	200
414254e3 ML	201	if (!down_new)
414254e3 ML	202	down_new = 1;
c6c8fea2	203
414254e3 ML	204	if (!up_new)
414254e3 ML	205	up_new = down_new / 5;
c6c8fea2	206
414254e3 ML	207	if (!up_new)
414254e3 ML	208	up_new = 1;
c6c8fea2	209
414254e3	210	if ((down_curr == down_new) && (up_curr == up_new))
dafe94b2 ML	211	return count;
dafe94b2 ML	212
4e820e72	213	batadv_gw_reselect(bat_priv);
3e34819e	214	batadv_info(net_dev,
414254e3 ML	215	"Changing gateway bandwidth from: '%u.%u/%u.%u MBit' to: '%u.%u/%u.%u MBit'\n",
	216	down_curr / 10, down_curr % 10, up_curr / 10, up_curr % 10,
	217	down_new / 10, down_new % 10, up_new / 10, up_new % 10);
c6c8fea2	218
414254e3 ML	219	atomic_set(&bat_priv->gw.bandwidth_down, down_new);
	220	atomic_set(&bat_priv->gw.bandwidth_up, up_new);
	221	batadv_gw_tvlv_container_update(bat_priv);
c6c8fea2	222
c6c8fea2 SE	223	return count;
c6c8fea2 SE	224	}
414254e3 ML	225
	226	/**
	227	* batadv_gw_tvlv_ogm_handler_v1 - process incoming gateway tvlv container
	228	* @bat_priv: the bat priv with all the soft interface information
	229	* @orig: the orig_node of the ogm
	230	* @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
	231	* @tvlv_value: tvlv buffer containing the gateway data
	232	* @tvlv_value_len: tvlv buffer length
	233	*/
	234	static void batadv_gw_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
	235	struct batadv_orig_node *orig,
6b5e971a SE	236	u8 flags,
6b5e971a SE	237	void *tvlv_value, u16 tvlv_value_len)
414254e3 ML	238	{
	239	struct batadv_tvlv_gateway_data gateway, *gateway_ptr;
	240
	241	/* only fetch the tvlv value if the handler wasn't called via the
	242	* CIFNOTFND flag and if there is data to fetch
	243	*/
	244	if ((flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND) \|\|
	245	(tvlv_value_len < sizeof(gateway))) {
	246	gateway.bandwidth_down = 0;
	247	gateway.bandwidth_up = 0;
	248	} else {
	249	gateway_ptr = tvlv_value;
	250	gateway.bandwidth_down = gateway_ptr->bandwidth_down;
	251	gateway.bandwidth_up = gateway_ptr->bandwidth_up;
	252	if ((gateway.bandwidth_down == 0) \|\|
	253	(gateway.bandwidth_up == 0)) {
	254	gateway.bandwidth_down = 0;
	255	gateway.bandwidth_up = 0;
	256	}
	257	}
	258
	259	batadv_gw_node_update(bat_priv, orig, &gateway);
	260
	261	/* restart gateway selection if fast or late switching was enabled */
	262	if ((gateway.bandwidth_down != 0) &&
	263	(atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_CLIENT) &&
	264	(atomic_read(&bat_priv->gw_sel_class) > 2))
	265	batadv_gw_check_election(bat_priv, orig);
	266	}
	267
	268	/**
	269	* batadv_gw_init - initialise the gateway handling internals
	270	* @bat_priv: the bat priv with all the soft interface information
	271	*/
	272	void batadv_gw_init(struct batadv_priv *bat_priv)
	273	{
	274	batadv_tvlv_handler_register(bat_priv, batadv_gw_tvlv_ogm_handler_v1,
	275	NULL, BATADV_TVLV_GW, 1,
	276	BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
	277	}
	278
	279	/**
	280	* batadv_gw_free - free the gateway handling internals
	281	* @bat_priv: the bat priv with all the soft interface information
	282	*/
	283	void batadv_gw_free(struct batadv_priv *bat_priv)
	284	{
	285	batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1);
	286	batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_GW, 1);
	287	}