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 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of version 2 of the GNU General Public 8 * License as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it will be useful, but 11 * WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 * General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, see <http://www.gnu.org/licenses/>. 17 */ 18 19 #include "gateway_common.h" 20 #include "main.h" 21 22 #include <linux/atomic.h> 23 #include <linux/byteorder/generic.h> 24 #include <linux/errno.h> 25 #include <linux/kernel.h> 26 #include <linux/math64.h> 27 #include <linux/netdevice.h> 28 #include <linux/stddef.h> 29 #include <linux/string.h> 30 #include <uapi/linux/batadv_packet.h> 31 #include <uapi/linux/batman_adv.h> 32 33 #include "gateway_client.h" 34 #include "log.h" 35 #include "tvlv.h" 36 37 /** 38 * batadv_parse_throughput() - parse supplied string buffer to extract 39 * throughput information 40 * @net_dev: the soft interface net device 41 * @buff: string buffer to parse 42 * @description: text shown when throughput string cannot be parsed 43 * @throughput: pointer holding the returned throughput information 44 * 45 * Return: false on parse error and true otherwise. 46 */ 47 bool batadv_parse_throughput(struct net_device *net_dev, char *buff, 48 const char *description, u32 *throughput) 49 { 50 enum batadv_bandwidth_units bw_unit_type = BATADV_BW_UNIT_KBIT; 51 u64 lthroughput; 52 char *tmp_ptr; 53 int ret; 54 55 if (strlen(buff) > 4) { 56 tmp_ptr = buff + strlen(buff) - 4; 57 58 if (strncasecmp(tmp_ptr, "mbit", 4) == 0) 59 bw_unit_type = BATADV_BW_UNIT_MBIT; 60 61 if (strncasecmp(tmp_ptr, "kbit", 4) == 0 || 62 bw_unit_type == BATADV_BW_UNIT_MBIT) 63 *tmp_ptr = '\0'; 64 } 65 66 ret = kstrtou64(buff, 10, <hroughput); 67 if (ret) { 68 batadv_err(net_dev, 69 "Invalid throughput speed for %s: %s\n", 70 description, buff); 71 return false; 72 } 73 74 switch (bw_unit_type) { 75 case BATADV_BW_UNIT_MBIT: 76 /* prevent overflow */ 77 if (U64_MAX / 10 < lthroughput) { 78 batadv_err(net_dev, 79 "Throughput speed for %s too large: %s\n", 80 description, buff); 81 return false; 82 } 83 84 lthroughput *= 10; 85 break; 86 case BATADV_BW_UNIT_KBIT: 87 default: 88 lthroughput = div_u64(lthroughput, 100); 89 break; 90 } 91 92 if (lthroughput > U32_MAX) { 93 batadv_err(net_dev, 94 "Throughput speed for %s too large: %s\n", 95 description, buff); 96 return false; 97 } 98 99 *throughput = lthroughput; 100 101 return true; 102 } 103 104 /** 105 * batadv_parse_gw_bandwidth() - parse supplied string buffer to extract 106 * download and upload bandwidth information 107 * @net_dev: the soft interface net device 108 * @buff: string buffer to parse 109 * @down: pointer holding the returned download bandwidth information 110 * @up: pointer holding the returned upload bandwidth information 111 * 112 * Return: false on parse error and true otherwise. 113 */ 114 static bool batadv_parse_gw_bandwidth(struct net_device *net_dev, char *buff, 115 u32 *down, u32 *up) 116 { 117 char *slash_ptr; 118 bool ret; 119 120 slash_ptr = strchr(buff, '/'); 121 if (slash_ptr) 122 *slash_ptr = 0; 123 124 ret = batadv_parse_throughput(net_dev, buff, "download gateway speed", 125 down); 126 if (!ret) 127 return false; 128 129 /* we also got some upload info */ 130 if (slash_ptr) { 131 ret = batadv_parse_throughput(net_dev, slash_ptr + 1, 132 "upload gateway speed", up); 133 if (!ret) 134 return false; 135 } 136 137 return true; 138 } 139 140 /** 141 * batadv_gw_tvlv_container_update() - update the gw tvlv container after 142 * gateway setting change 143 * @bat_priv: the bat priv with all the soft interface information 144 */ 145 void batadv_gw_tvlv_container_update(struct batadv_priv *bat_priv) 146 { 147 struct batadv_tvlv_gateway_data gw; 148 u32 down, up; 149 char gw_mode; 150 151 gw_mode = atomic_read(&bat_priv->gw.mode); 152 153 switch (gw_mode) { 154 case BATADV_GW_MODE_OFF: 155 case BATADV_GW_MODE_CLIENT: 156 batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1); 157 break; 158 case BATADV_GW_MODE_SERVER: 159 down = atomic_read(&bat_priv->gw.bandwidth_down); 160 up = atomic_read(&bat_priv->gw.bandwidth_up); 161 gw.bandwidth_down = htonl(down); 162 gw.bandwidth_up = htonl(up); 163 batadv_tvlv_container_register(bat_priv, BATADV_TVLV_GW, 1, 164 &gw, sizeof(gw)); 165 break; 166 } 167 } 168 169 /** 170 * batadv_gw_bandwidth_set() - Parse and set download/upload gateway bandwidth 171 * from supplied string buffer 172 * @net_dev: netdev struct of the soft interface 173 * @buff: the buffer containing the user data 174 * @count: number of bytes in the buffer 175 * 176 * Return: 'count' on success or a negative error code in case of failure 177 */ 178 ssize_t batadv_gw_bandwidth_set(struct net_device *net_dev, char *buff, 179 size_t count) 180 { 181 struct batadv_priv *bat_priv = netdev_priv(net_dev); 182 u32 down_curr; 183 u32 up_curr; 184 u32 down_new = 0; 185 u32 up_new = 0; 186 bool ret; 187 188 down_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_down); 189 up_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_up); 190 191 ret = batadv_parse_gw_bandwidth(net_dev, buff, &down_new, &up_new); 192 if (!ret) 193 return -EINVAL; 194 195 if (!down_new) 196 down_new = 1; 197 198 if (!up_new) 199 up_new = down_new / 5; 200 201 if (!up_new) 202 up_new = 1; 203 204 if (down_curr == down_new && up_curr == up_new) 205 return count; 206 207 batadv_gw_reselect(bat_priv); 208 batadv_info(net_dev, 209 "Changing gateway bandwidth from: '%u.%u/%u.%u MBit' to: '%u.%u/%u.%u MBit'\n", 210 down_curr / 10, down_curr % 10, up_curr / 10, up_curr % 10, 211 down_new / 10, down_new % 10, up_new / 10, up_new % 10); 212 213 atomic_set(&bat_priv->gw.bandwidth_down, down_new); 214 atomic_set(&bat_priv->gw.bandwidth_up, up_new); 215 batadv_gw_tvlv_container_update(bat_priv); 216 217 return count; 218 } 219 220 /** 221 * batadv_gw_tvlv_ogm_handler_v1() - process incoming gateway tvlv container 222 * @bat_priv: the bat priv with all the soft interface information 223 * @orig: the orig_node of the ogm 224 * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags) 225 * @tvlv_value: tvlv buffer containing the gateway data 226 * @tvlv_value_len: tvlv buffer length 227 */ 228 static void batadv_gw_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv, 229 struct batadv_orig_node *orig, 230 u8 flags, 231 void *tvlv_value, u16 tvlv_value_len) 232 { 233 struct batadv_tvlv_gateway_data gateway, *gateway_ptr; 234 235 /* only fetch the tvlv value if the handler wasn't called via the 236 * CIFNOTFND flag and if there is data to fetch 237 */ 238 if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND || 239 tvlv_value_len < sizeof(gateway)) { 240 gateway.bandwidth_down = 0; 241 gateway.bandwidth_up = 0; 242 } else { 243 gateway_ptr = tvlv_value; 244 gateway.bandwidth_down = gateway_ptr->bandwidth_down; 245 gateway.bandwidth_up = gateway_ptr->bandwidth_up; 246 if (gateway.bandwidth_down == 0 || 247 gateway.bandwidth_up == 0) { 248 gateway.bandwidth_down = 0; 249 gateway.bandwidth_up = 0; 250 } 251 } 252 253 batadv_gw_node_update(bat_priv, orig, &gateway); 254 255 /* restart gateway selection */ 256 if (gateway.bandwidth_down != 0 && 257 atomic_read(&bat_priv->gw.mode) == BATADV_GW_MODE_CLIENT) 258 batadv_gw_check_election(bat_priv, orig); 259 } 260 261 /** 262 * batadv_gw_init() - initialise the gateway handling internals 263 * @bat_priv: the bat priv with all the soft interface information 264 */ 265 void batadv_gw_init(struct batadv_priv *bat_priv) 266 { 267 if (bat_priv->algo_ops->gw.init_sel_class) 268 bat_priv->algo_ops->gw.init_sel_class(bat_priv); 269 else 270 atomic_set(&bat_priv->gw.sel_class, 1); 271 272 batadv_tvlv_handler_register(bat_priv, batadv_gw_tvlv_ogm_handler_v1, 273 NULL, BATADV_TVLV_GW, 1, 274 BATADV_TVLV_HANDLER_OGM_CIFNOTFND); 275 } 276 277 /** 278 * batadv_gw_free() - free the gateway handling internals 279 * @bat_priv: the bat priv with all the soft interface information 280 */ 281 void batadv_gw_free(struct batadv_priv *bat_priv) 282 { 283 batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1); 284 batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_GW, 1); 285 } 286