summaryrefslogtreecommitdiff
path: root/net/batman-adv/gateway_common.c
blob: b3e156af2256cff85a1d362112ccf577ac7fa348 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2009-2017  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 "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);
}