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  */
32 static 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  */
115 void 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 
139 ssize_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 
175 end:
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  */
187 static 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  */
226 void 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  */
237 void 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