xref: /linux/net/batman-adv/gateway_common.c (revision 005438a8eef063495ac059d128eea71b58de50e5)
1 /* Copyright (C) 2009-2015 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 "gateway_common.h"
19 #include "main.h"
20 
21 #include <linux/atomic.h>
22 #include <linux/byteorder/generic.h>
23 #include <linux/kernel.h>
24 #include <linux/netdevice.h>
25 #include <linux/stddef.h>
26 #include <linux/string.h>
27 
28 #include "gateway_client.h"
29 #include "packet.h"
30 
31 /**
32  * batadv_parse_gw_bandwidth - parse supplied string buffer to extract download
33  *  and upload bandwidth information
34  * @net_dev: the soft interface net device
35  * @buff: string buffer to parse
36  * @down: pointer holding the returned download bandwidth information
37  * @up: pointer holding the returned upload bandwidth information
38  *
39  * Returns false on parse error and true otherwise.
40  */
41 static bool batadv_parse_gw_bandwidth(struct net_device *net_dev, char *buff,
42 				      uint32_t *down, uint32_t *up)
43 {
44 	enum batadv_bandwidth_units bw_unit_type = BATADV_BW_UNIT_KBIT;
45 	char *slash_ptr, *tmp_ptr;
46 	long ldown, lup;
47 	int ret;
48 
49 	slash_ptr = strchr(buff, '/');
50 	if (slash_ptr)
51 		*slash_ptr = 0;
52 
53 	if (strlen(buff) > 4) {
54 		tmp_ptr = buff + strlen(buff) - 4;
55 
56 		if (strncasecmp(tmp_ptr, "mbit", 4) == 0)
57 			bw_unit_type = BATADV_BW_UNIT_MBIT;
58 
59 		if ((strncasecmp(tmp_ptr, "kbit", 4) == 0) ||
60 		    (bw_unit_type == BATADV_BW_UNIT_MBIT))
61 			*tmp_ptr = '\0';
62 	}
63 
64 	ret = kstrtol(buff, 10, &ldown);
65 	if (ret) {
66 		batadv_err(net_dev,
67 			   "Download speed of gateway mode invalid: %s\n",
68 			   buff);
69 		return false;
70 	}
71 
72 	switch (bw_unit_type) {
73 	case BATADV_BW_UNIT_MBIT:
74 		*down = ldown * 10;
75 		break;
76 	case BATADV_BW_UNIT_KBIT:
77 	default:
78 		*down = ldown / 100;
79 		break;
80 	}
81 
82 	/* we also got some upload info */
83 	if (slash_ptr) {
84 		bw_unit_type = BATADV_BW_UNIT_KBIT;
85 
86 		if (strlen(slash_ptr + 1) > 4) {
87 			tmp_ptr = slash_ptr + 1 - 4 + strlen(slash_ptr + 1);
88 
89 			if (strncasecmp(tmp_ptr, "mbit", 4) == 0)
90 				bw_unit_type = BATADV_BW_UNIT_MBIT;
91 
92 			if ((strncasecmp(tmp_ptr, "kbit", 4) == 0) ||
93 			    (bw_unit_type == BATADV_BW_UNIT_MBIT))
94 				*tmp_ptr = '\0';
95 		}
96 
97 		ret = kstrtol(slash_ptr + 1, 10, &lup);
98 		if (ret) {
99 			batadv_err(net_dev,
100 				   "Upload speed of gateway mode invalid: %s\n",
101 				   slash_ptr + 1);
102 			return false;
103 		}
104 
105 		switch (bw_unit_type) {
106 		case BATADV_BW_UNIT_MBIT:
107 			*up = lup * 10;
108 			break;
109 		case BATADV_BW_UNIT_KBIT:
110 		default:
111 			*up = lup / 100;
112 			break;
113 		}
114 	}
115 
116 	return true;
117 }
118 
119 /**
120  * batadv_gw_tvlv_container_update - update the gw tvlv container after gateway
121  *  setting change
122  * @bat_priv: the bat priv with all the soft interface information
123  */
124 void batadv_gw_tvlv_container_update(struct batadv_priv *bat_priv)
125 {
126 	struct batadv_tvlv_gateway_data gw;
127 	uint32_t down, up;
128 	char gw_mode;
129 
130 	gw_mode = atomic_read(&bat_priv->gw_mode);
131 
132 	switch (gw_mode) {
133 	case BATADV_GW_MODE_OFF:
134 	case BATADV_GW_MODE_CLIENT:
135 		batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1);
136 		break;
137 	case BATADV_GW_MODE_SERVER:
138 		down = atomic_read(&bat_priv->gw.bandwidth_down);
139 		up = atomic_read(&bat_priv->gw.bandwidth_up);
140 		gw.bandwidth_down = htonl(down);
141 		gw.bandwidth_up = htonl(up);
142 		batadv_tvlv_container_register(bat_priv, BATADV_TVLV_GW, 1,
143 					       &gw, sizeof(gw));
144 		break;
145 	}
146 }
147 
148 ssize_t batadv_gw_bandwidth_set(struct net_device *net_dev, char *buff,
149 				size_t count)
150 {
151 	struct batadv_priv *bat_priv = netdev_priv(net_dev);
152 	uint32_t down_curr, up_curr, down_new = 0, up_new = 0;
153 	bool ret;
154 
155 	down_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_down);
156 	up_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_up);
157 
158 	ret = batadv_parse_gw_bandwidth(net_dev, buff, &down_new, &up_new);
159 	if (!ret)
160 		goto end;
161 
162 	if (!down_new)
163 		down_new = 1;
164 
165 	if (!up_new)
166 		up_new = down_new / 5;
167 
168 	if (!up_new)
169 		up_new = 1;
170 
171 	if ((down_curr == down_new) && (up_curr == up_new))
172 		return count;
173 
174 	batadv_gw_reselect(bat_priv);
175 	batadv_info(net_dev,
176 		    "Changing gateway bandwidth from: '%u.%u/%u.%u MBit' to: '%u.%u/%u.%u MBit'\n",
177 		    down_curr / 10, down_curr % 10, up_curr / 10, up_curr % 10,
178 		    down_new / 10, down_new % 10, up_new / 10, up_new % 10);
179 
180 	atomic_set(&bat_priv->gw.bandwidth_down, down_new);
181 	atomic_set(&bat_priv->gw.bandwidth_up, up_new);
182 	batadv_gw_tvlv_container_update(bat_priv);
183 
184 end:
185 	return count;
186 }
187 
188 /**
189  * batadv_gw_tvlv_ogm_handler_v1 - process incoming gateway tvlv container
190  * @bat_priv: the bat priv with all the soft interface information
191  * @orig: the orig_node of the ogm
192  * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
193  * @tvlv_value: tvlv buffer containing the gateway data
194  * @tvlv_value_len: tvlv buffer length
195  */
196 static void batadv_gw_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
197 					  struct batadv_orig_node *orig,
198 					  uint8_t flags,
199 					  void *tvlv_value,
200 					  uint16_t tvlv_value_len)
201 {
202 	struct batadv_tvlv_gateway_data gateway, *gateway_ptr;
203 
204 	/* only fetch the tvlv value if the handler wasn't called via the
205 	 * CIFNOTFND flag and if there is data to fetch
206 	 */
207 	if ((flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND) ||
208 	    (tvlv_value_len < sizeof(gateway))) {
209 		gateway.bandwidth_down = 0;
210 		gateway.bandwidth_up = 0;
211 	} else {
212 		gateway_ptr = tvlv_value;
213 		gateway.bandwidth_down = gateway_ptr->bandwidth_down;
214 		gateway.bandwidth_up = gateway_ptr->bandwidth_up;
215 		if ((gateway.bandwidth_down == 0) ||
216 		    (gateway.bandwidth_up == 0)) {
217 			gateway.bandwidth_down = 0;
218 			gateway.bandwidth_up = 0;
219 		}
220 	}
221 
222 	batadv_gw_node_update(bat_priv, orig, &gateway);
223 
224 	/* restart gateway selection if fast or late switching was enabled */
225 	if ((gateway.bandwidth_down != 0) &&
226 	    (atomic_read(&bat_priv->gw_mode) == BATADV_GW_MODE_CLIENT) &&
227 	    (atomic_read(&bat_priv->gw_sel_class) > 2))
228 		batadv_gw_check_election(bat_priv, orig);
229 }
230 
231 /**
232  * batadv_gw_init - initialise the gateway handling internals
233  * @bat_priv: the bat priv with all the soft interface information
234  */
235 void batadv_gw_init(struct batadv_priv *bat_priv)
236 {
237 	batadv_tvlv_handler_register(bat_priv, batadv_gw_tvlv_ogm_handler_v1,
238 				     NULL, BATADV_TVLV_GW, 1,
239 				     BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
240 }
241 
242 /**
243  * batadv_gw_free - free the gateway handling internals
244  * @bat_priv: the bat priv with all the soft interface information
245  */
246 void batadv_gw_free(struct batadv_priv *bat_priv)
247 {
248 	batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1);
249 	batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_GW, 1);
250 }
251