1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (C) 2009-2019 B.A.T.M.A.N. contributors:
3 *
4 * Marek Lindner
5 */
6
7 #include "gateway_common.h"
8 #include "main.h"
9
10 #include <linux/atomic.h>
11 #include <linux/byteorder/generic.h>
12 #include <linux/errno.h>
13 #include <linux/kernel.h>
14 #include <linux/limits.h>
15 #include <linux/math64.h>
16 #include <linux/netdevice.h>
17 #include <linux/stddef.h>
18 #include <linux/string.h>
19 #include <uapi/linux/batadv_packet.h>
20 #include <uapi/linux/batman_adv.h>
21
22 #include "gateway_client.h"
23 #include "log.h"
24 #include "tvlv.h"
25
26 /**
27 * batadv_parse_throughput() - parse supplied string buffer to extract
28 * throughput information
29 * @net_dev: the soft interface net device
30 * @buff: string buffer to parse
31 * @description: text shown when throughput string cannot be parsed
32 * @throughput: pointer holding the returned throughput information
33 *
34 * Return: false on parse error and true otherwise.
35 */
batadv_parse_throughput(struct net_device * net_dev,char * buff,const char * description,u32 * throughput)36 bool batadv_parse_throughput(struct net_device *net_dev, char *buff,
37 const char *description, u32 *throughput)
38 {
39 enum batadv_bandwidth_units bw_unit_type = BATADV_BW_UNIT_KBIT;
40 u64 lthroughput;
41 char *tmp_ptr;
42 int ret;
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 = kstrtou64(buff, 10, <hroughput);
56 if (ret) {
57 batadv_err(net_dev,
58 "Invalid throughput speed for %s: %s\n",
59 description, buff);
60 return false;
61 }
62
63 switch (bw_unit_type) {
64 case BATADV_BW_UNIT_MBIT:
65 /* prevent overflow */
66 if (U64_MAX / 10 < lthroughput) {
67 batadv_err(net_dev,
68 "Throughput speed for %s too large: %s\n",
69 description, buff);
70 return false;
71 }
72
73 lthroughput *= 10;
74 break;
75 case BATADV_BW_UNIT_KBIT:
76 default:
77 lthroughput = div_u64(lthroughput, 100);
78 break;
79 }
80
81 if (lthroughput > U32_MAX) {
82 batadv_err(net_dev,
83 "Throughput speed for %s too large: %s\n",
84 description, buff);
85 return false;
86 }
87
88 *throughput = lthroughput;
89
90 return true;
91 }
92
93 /**
94 * batadv_parse_gw_bandwidth() - parse supplied string buffer to extract
95 * download and upload bandwidth information
96 * @net_dev: the soft interface net device
97 * @buff: string buffer to parse
98 * @down: pointer holding the returned download bandwidth information
99 * @up: pointer holding the returned upload bandwidth information
100 *
101 * Return: false on parse error and true otherwise.
102 */
batadv_parse_gw_bandwidth(struct net_device * net_dev,char * buff,u32 * down,u32 * up)103 static bool batadv_parse_gw_bandwidth(struct net_device *net_dev, char *buff,
104 u32 *down, u32 *up)
105 {
106 char *slash_ptr;
107 bool ret;
108
109 slash_ptr = strchr(buff, '/');
110 if (slash_ptr)
111 *slash_ptr = 0;
112
113 ret = batadv_parse_throughput(net_dev, buff, "download gateway speed",
114 down);
115 if (!ret)
116 return false;
117
118 /* we also got some upload info */
119 if (slash_ptr) {
120 ret = batadv_parse_throughput(net_dev, slash_ptr + 1,
121 "upload gateway speed", up);
122 if (!ret)
123 return false;
124 }
125
126 return true;
127 }
128
129 /**
130 * batadv_gw_tvlv_container_update() - update the gw tvlv container after
131 * gateway setting change
132 * @bat_priv: the bat priv with all the soft interface information
133 */
batadv_gw_tvlv_container_update(struct batadv_priv * bat_priv)134 void batadv_gw_tvlv_container_update(struct batadv_priv *bat_priv)
135 {
136 struct batadv_tvlv_gateway_data gw;
137 u32 down, up;
138 char gw_mode;
139
140 gw_mode = atomic_read(&bat_priv->gw.mode);
141
142 switch (gw_mode) {
143 case BATADV_GW_MODE_OFF:
144 case BATADV_GW_MODE_CLIENT:
145 batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1);
146 break;
147 case BATADV_GW_MODE_SERVER:
148 down = atomic_read(&bat_priv->gw.bandwidth_down);
149 up = atomic_read(&bat_priv->gw.bandwidth_up);
150 gw.bandwidth_down = htonl(down);
151 gw.bandwidth_up = htonl(up);
152 batadv_tvlv_container_register(bat_priv, BATADV_TVLV_GW, 1,
153 &gw, sizeof(gw));
154 break;
155 }
156 }
157
158 /**
159 * batadv_gw_bandwidth_set() - Parse and set download/upload gateway bandwidth
160 * from supplied string buffer
161 * @net_dev: netdev struct of the soft interface
162 * @buff: the buffer containing the user data
163 * @count: number of bytes in the buffer
164 *
165 * Return: 'count' on success or a negative error code in case of failure
166 */
batadv_gw_bandwidth_set(struct net_device * net_dev,char * buff,size_t count)167 ssize_t batadv_gw_bandwidth_set(struct net_device *net_dev, char *buff,
168 size_t count)
169 {
170 struct batadv_priv *bat_priv = netdev_priv(net_dev);
171 u32 down_curr;
172 u32 up_curr;
173 u32 down_new = 0;
174 u32 up_new = 0;
175 bool ret;
176
177 down_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_down);
178 up_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_up);
179
180 ret = batadv_parse_gw_bandwidth(net_dev, buff, &down_new, &up_new);
181 if (!ret)
182 return -EINVAL;
183
184 if (!down_new)
185 down_new = 1;
186
187 if (!up_new)
188 up_new = down_new / 5;
189
190 if (!up_new)
191 up_new = 1;
192
193 if (down_curr == down_new && up_curr == up_new)
194 return count;
195
196 batadv_gw_reselect(bat_priv);
197 batadv_info(net_dev,
198 "Changing gateway bandwidth from: '%u.%u/%u.%u MBit' to: '%u.%u/%u.%u MBit'\n",
199 down_curr / 10, down_curr % 10, up_curr / 10, up_curr % 10,
200 down_new / 10, down_new % 10, up_new / 10, up_new % 10);
201
202 atomic_set(&bat_priv->gw.bandwidth_down, down_new);
203 atomic_set(&bat_priv->gw.bandwidth_up, up_new);
204 batadv_gw_tvlv_container_update(bat_priv);
205
206 return count;
207 }
208
209 /**
210 * batadv_gw_tvlv_ogm_handler_v1() - process incoming gateway tvlv container
211 * @bat_priv: the bat priv with all the soft interface information
212 * @orig: the orig_node of the ogm
213 * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
214 * @tvlv_value: tvlv buffer containing the gateway data
215 * @tvlv_value_len: tvlv buffer length
216 */
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)217 static void batadv_gw_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
218 struct batadv_orig_node *orig,
219 u8 flags,
220 void *tvlv_value, u16 tvlv_value_len)
221 {
222 struct batadv_tvlv_gateway_data gateway, *gateway_ptr;
223
224 /* only fetch the tvlv value if the handler wasn't called via the
225 * CIFNOTFND flag and if there is data to fetch
226 */
227 if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND ||
228 tvlv_value_len < sizeof(gateway)) {
229 gateway.bandwidth_down = 0;
230 gateway.bandwidth_up = 0;
231 } else {
232 gateway_ptr = tvlv_value;
233 gateway.bandwidth_down = gateway_ptr->bandwidth_down;
234 gateway.bandwidth_up = gateway_ptr->bandwidth_up;
235 if (gateway.bandwidth_down == 0 ||
236 gateway.bandwidth_up == 0) {
237 gateway.bandwidth_down = 0;
238 gateway.bandwidth_up = 0;
239 }
240 }
241
242 batadv_gw_node_update(bat_priv, orig, &gateway);
243
244 /* restart gateway selection */
245 if (gateway.bandwidth_down != 0 &&
246 atomic_read(&bat_priv->gw.mode) == BATADV_GW_MODE_CLIENT)
247 batadv_gw_check_election(bat_priv, orig);
248 }
249
250 /**
251 * batadv_gw_init() - initialise the gateway handling internals
252 * @bat_priv: the bat priv with all the soft interface information
253 */
batadv_gw_init(struct batadv_priv * bat_priv)254 void batadv_gw_init(struct batadv_priv *bat_priv)
255 {
256 if (bat_priv->algo_ops->gw.init_sel_class)
257 bat_priv->algo_ops->gw.init_sel_class(bat_priv);
258 else
259 atomic_set(&bat_priv->gw.sel_class, 1);
260
261 batadv_tvlv_handler_register(bat_priv, batadv_gw_tvlv_ogm_handler_v1,
262 NULL, BATADV_TVLV_GW, 1,
263 BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
264 }
265
266 /**
267 * batadv_gw_free() - free the gateway handling internals
268 * @bat_priv: the bat priv with all the soft interface information
269 */
batadv_gw_free(struct batadv_priv * bat_priv)270 void batadv_gw_free(struct batadv_priv *bat_priv)
271 {
272 batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1);
273 batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_GW, 1);
274 }
275