1/* Copyright (C) 2009-2014 B.A.T.M.A.N. contributors:
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
15 * along with this program; if not, see <http://www.gnu.org/licenses/>.
16 */
17
18#include "main.h"
19#include "gateway_common.h"
20#include "gateway_client.h"
21
22/**
23 * batadv_parse_gw_bandwidth - parse supplied string buffer to extract download
24 *  and upload bandwidth information
25 * @net_dev: the soft interface net device
26 * @buff: string buffer to parse
27 * @down: pointer holding the returned download bandwidth information
28 * @up: pointer holding the returned upload bandwidth information
29 *
30 * Returns false on parse error and true otherwise.
31 */
32static bool batadv_parse_gw_bandwidth(struct net_device *net_dev, char *buff,
33				      uint32_t *down, uint32_t *up)
34{
35	enum batadv_bandwidth_units bw_unit_type = BATADV_BW_UNIT_KBIT;
36	char *slash_ptr, *tmp_ptr;
37	long ldown, lup;
38	int ret;
39
40	slash_ptr = strchr(buff, '/');
41	if (slash_ptr)
42		*slash_ptr = 0;
43
44	if (strlen(buff) > 4) {
45		tmp_ptr = buff + strlen(buff) - 4;
46
47		if (strncasecmp(tmp_ptr, "mbit", 4) == 0)
48			bw_unit_type = BATADV_BW_UNIT_MBIT;
49
50		if ((strncasecmp(tmp_ptr, "kbit", 4) == 0) ||
51		    (bw_unit_type == BATADV_BW_UNIT_MBIT))
52			*tmp_ptr = '\0';
53	}
54
55	ret = kstrtol(buff, 10, &ldown);
56	if (ret) {
57		batadv_err(net_dev,
58			   "Download speed of gateway mode invalid: %s\n",
59			   buff);
60		return false;
61	}
62
63	switch (bw_unit_type) {
64	case BATADV_BW_UNIT_MBIT:
65		*down = ldown * 10;
66		break;
67	case BATADV_BW_UNIT_KBIT:
68	default:
69		*down = ldown / 100;
70		break;
71	}
72
73	/* we also got some upload info */
74	if (slash_ptr) {
75		bw_unit_type = BATADV_BW_UNIT_KBIT;
76
77		if (strlen(slash_ptr + 1) > 4) {
78			tmp_ptr = slash_ptr + 1 - 4 + strlen(slash_ptr + 1);
79
80			if (strncasecmp(tmp_ptr, "mbit", 4) == 0)
81				bw_unit_type = BATADV_BW_UNIT_MBIT;
82
83			if ((strncasecmp(tmp_ptr, "kbit", 4) == 0) ||
84			    (bw_unit_type == BATADV_BW_UNIT_MBIT))
85				*tmp_ptr = '\0';
86		}
87
88		ret = kstrtol(slash_ptr + 1, 10, &lup);
89		if (ret) {
90			batadv_err(net_dev,
91				   "Upload speed of gateway mode invalid: %s\n",
92				   slash_ptr + 1);
93			return false;
94		}
95
96		switch (bw_unit_type) {
97		case BATADV_BW_UNIT_MBIT:
98			*up = lup * 10;
99			break;
100		case BATADV_BW_UNIT_KBIT:
101		default:
102			*up = lup / 100;
103			break;
104		}
105	}
106
107	return true;
108}
109
110/**
111 * batadv_gw_tvlv_container_update - update the gw tvlv container after gateway
112 *  setting change
113 * @bat_priv: the bat priv with all the soft interface information
114 */
115void batadv_gw_tvlv_container_update(struct batadv_priv *bat_priv)
116{
117	struct batadv_tvlv_gateway_data gw;
118	uint32_t down, up;
119	char gw_mode;
120
121	gw_mode = atomic_read(&bat_priv->gw_mode);
122
123	switch (gw_mode) {
124	case BATADV_GW_MODE_OFF:
125	case BATADV_GW_MODE_CLIENT:
126		batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1);
127		break;
128	case BATADV_GW_MODE_SERVER:
129		down = atomic_read(&bat_priv->gw.bandwidth_down);
130		up = atomic_read(&bat_priv->gw.bandwidth_up);
131		gw.bandwidth_down = htonl(down);
132		gw.bandwidth_up = htonl(up);
133		batadv_tvlv_container_register(bat_priv, BATADV_TVLV_GW, 1,
134					       &gw, sizeof(gw));
135		break;
136	}
137}
138
139ssize_t batadv_gw_bandwidth_set(struct net_device *net_dev, char *buff,
140				size_t count)
141{
142	struct batadv_priv *bat_priv = netdev_priv(net_dev);
143	uint32_t down_curr, up_curr, down_new = 0, up_new = 0;
144	bool ret;
145
146	down_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_down);
147	up_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_up);
148
149	ret = batadv_parse_gw_bandwidth(net_dev, buff, &down_new, &up_new);
150	if (!ret)
151		goto end;
152
153	if (!down_new)
154		down_new = 1;
155
156	if (!up_new)
157		up_new = down_new / 5;
158
159	if (!up_new)
160		up_new = 1;
161
162	if ((down_curr == down_new) && (up_curr == up_new))
163		return count;
164
165	batadv_gw_reselect(bat_priv);
166	batadv_info(net_dev,
167		    "Changing gateway bandwidth from: '%u.%u/%u.%u MBit' to: '%u.%u/%u.%u MBit'\n",
168		    down_curr / 10, down_curr % 10, up_curr / 10, up_curr % 10,
169		    down_new / 10, down_new % 10, up_new / 10, up_new % 10);
170
171	atomic_set(&bat_priv->gw.bandwidth_down, down_new);
172	atomic_set(&bat_priv->gw.bandwidth_up, up_new);
173	batadv_gw_tvlv_container_update(bat_priv);
174
175end:
176	return count;
177}
178
179/**
180 * batadv_gw_tvlv_ogm_handler_v1 - process incoming gateway tvlv container
181 * @bat_priv: the bat priv with all the soft interface information
182 * @orig: the orig_node of the ogm
183 * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
184 * @tvlv_value: tvlv buffer containing the gateway data
185 * @tvlv_value_len: tvlv buffer length
186 */
187static void batadv_gw_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
188					  struct batadv_orig_node *orig,
189					  uint8_t flags,
190					  void *tvlv_value,
191					  uint16_t tvlv_value_len)
192{
193	struct batadv_tvlv_gateway_data gateway, *gateway_ptr;
194
195	/* only fetch the tvlv value if the handler wasn't called via the
196	 * CIFNOTFND flag and if there is data to fetch
197	 */
198	if ((flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND) ||
199	    (tvlv_value_len < sizeof(gateway))) {
200		gateway.bandwidth_down = 0;
201		gateway.bandwidth_up = 0;
202	} else {
203		gateway_ptr = tvlv_value;
204		gateway.bandwidth_down = gateway_ptr->bandwidth_down;
205		gateway.bandwidth_up = gateway_ptr->bandwidth_up;
206		if ((gateway.bandwidth_down == 0) ||
207		    (gateway.bandwidth_up == 0)) {
208			gateway.bandwidth_down = 0;
209			gateway.bandwidth_up = 0;
210		}
211	}
212
213	batadv_gw_node_update(bat_priv, orig, &gateway);
214
215	/* restart gateway selection if fast or late switching was enabled */
216	if ((gateway.bandwidth_down != 0) &&
217	    (atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_CLIENT) &&
218	    (atomic_read(&bat_priv->gw_sel_class) > 2))
219		batadv_gw_check_election(bat_priv, orig);
220}
221
222/**
223 * batadv_gw_init - initialise the gateway handling internals
224 * @bat_priv: the bat priv with all the soft interface information
225 */
226void batadv_gw_init(struct batadv_priv *bat_priv)
227{
228	batadv_tvlv_handler_register(bat_priv, batadv_gw_tvlv_ogm_handler_v1,
229				     NULL, BATADV_TVLV_GW, 1,
230				     BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
231}
232
233/**
234 * batadv_gw_free - free the gateway handling internals
235 * @bat_priv: the bat priv with all the soft interface information
236 */
237void batadv_gw_free(struct batadv_priv *bat_priv)
238{
239	batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1);
240	batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_GW, 1);
241}
242