1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (C) 2009-2018 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 32 #include "gateway_client.h" 33 #include "log.h" 34 #include "tvlv.h" 35 36 /** 37 * batadv_parse_throughput() - parse supplied string buffer to extract 38 * throughput information 39 * @net_dev: the soft interface net device 40 * @buff: string buffer to parse 41 * @description: text shown when throughput string cannot be parsed 42 * @throughput: pointer holding the returned throughput information 43 * 44 * Return: false on parse error and true otherwise. 45 */ 46 bool batadv_parse_throughput(struct net_device *net_dev, char *buff, 47 const char *description, u32 *throughput) 48 { 49 enum batadv_bandwidth_units bw_unit_type = BATADV_BW_UNIT_KBIT; 50 u64 lthroughput; 51 char *tmp_ptr; 52 int ret; 53 54 if (strlen(buff) > 4) { 55 tmp_ptr = buff + strlen(buff) - 4; 56 57 if (strncasecmp(tmp_ptr, "mbit", 4) == 0) 58 bw_unit_type = BATADV_BW_UNIT_MBIT; 59 60 if (strncasecmp(tmp_ptr, "kbit", 4) == 0 || 61 bw_unit_type == BATADV_BW_UNIT_MBIT) 62 *tmp_ptr = '\0'; 63 } 64 65 ret = kstrtou64(buff, 10, <hroughput); 66 if (ret) { 67 batadv_err(net_dev, 68 "Invalid throughput speed for %s: %s\n", 69 description, buff); 70 return false; 71 } 72 73 switch (bw_unit_type) { 74 case BATADV_BW_UNIT_MBIT: 75 /* prevent overflow */ 76 if (U64_MAX / 10 < lthroughput) { 77 batadv_err(net_dev, 78 "Throughput speed for %s too large: %s\n", 79 description, buff); 80 return false; 81 } 82 83 lthroughput *= 10; 84 break; 85 case BATADV_BW_UNIT_KBIT: 86 default: 87 lthroughput = div_u64(lthroughput, 100); 88 break; 89 } 90 91 if (lthroughput > U32_MAX) { 92 batadv_err(net_dev, 93 "Throughput speed for %s too large: %s\n", 94 description, buff); 95 return false; 96 } 97 98 *throughput = lthroughput; 99 100 return true; 101 } 102 103 /** 104 * batadv_parse_gw_bandwidth() - parse supplied string buffer to extract 105 * download and upload bandwidth information 106 * @net_dev: the soft interface net device 107 * @buff: string buffer to parse 108 * @down: pointer holding the returned download bandwidth information 109 * @up: pointer holding the returned upload bandwidth information 110 * 111 * Return: false on parse error and true otherwise. 112 */ 113 static bool batadv_parse_gw_bandwidth(struct net_device *net_dev, char *buff, 114 u32 *down, u32 *up) 115 { 116 char *slash_ptr; 117 bool ret; 118 119 slash_ptr = strchr(buff, '/'); 120 if (slash_ptr) 121 *slash_ptr = 0; 122 123 ret = batadv_parse_throughput(net_dev, buff, "download gateway speed", 124 down); 125 if (!ret) 126 return false; 127 128 /* we also got some upload info */ 129 if (slash_ptr) { 130 ret = batadv_parse_throughput(net_dev, slash_ptr + 1, 131 "upload gateway speed", up); 132 if (!ret) 133 return false; 134 } 135 136 return true; 137 } 138 139 /** 140 * batadv_gw_tvlv_container_update() - update the gw tvlv container after 141 * gateway setting change 142 * @bat_priv: the bat priv with all the soft interface information 143 */ 144 void batadv_gw_tvlv_container_update(struct batadv_priv *bat_priv) 145 { 146 struct batadv_tvlv_gateway_data gw; 147 u32 down, up; 148 char gw_mode; 149 150 gw_mode = atomic_read(&bat_priv->gw.mode); 151 152 switch (gw_mode) { 153 case BATADV_GW_MODE_OFF: 154 case BATADV_GW_MODE_CLIENT: 155 batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1); 156 break; 157 case BATADV_GW_MODE_SERVER: 158 down = atomic_read(&bat_priv->gw.bandwidth_down); 159 up = atomic_read(&bat_priv->gw.bandwidth_up); 160 gw.bandwidth_down = htonl(down); 161 gw.bandwidth_up = htonl(up); 162 batadv_tvlv_container_register(bat_priv, BATADV_TVLV_GW, 1, 163 &gw, sizeof(gw)); 164 break; 165 } 166 } 167 168 /** 169 * batadv_gw_bandwidth_set() - Parse and set download/upload gateway bandwidth 170 * from supplied string buffer 171 * @net_dev: netdev struct of the soft interface 172 * @buff: the buffer containing the user data 173 * @count: number of bytes in the buffer 174 * 175 * Return: 'count' on success or a negative error code in case of failure 176 */ 177 ssize_t batadv_gw_bandwidth_set(struct net_device *net_dev, char *buff, 178 size_t count) 179 { 180 struct batadv_priv *bat_priv = netdev_priv(net_dev); 181 u32 down_curr; 182 u32 up_curr; 183 u32 down_new = 0; 184 u32 up_new = 0; 185 bool ret; 186 187 down_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_down); 188 up_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_up); 189 190 ret = batadv_parse_gw_bandwidth(net_dev, buff, &down_new, &up_new); 191 if (!ret) 192 return -EINVAL; 193 194 if (!down_new) 195 down_new = 1; 196 197 if (!up_new) 198 up_new = down_new / 5; 199 200 if (!up_new) 201 up_new = 1; 202 203 if (down_curr == down_new && up_curr == up_new) 204 return count; 205 206 batadv_gw_reselect(bat_priv); 207 batadv_info(net_dev, 208 "Changing gateway bandwidth from: '%u.%u/%u.%u MBit' to: '%u.%u/%u.%u MBit'\n", 209 down_curr / 10, down_curr % 10, up_curr / 10, up_curr % 10, 210 down_new / 10, down_new % 10, up_new / 10, up_new % 10); 211 212 atomic_set(&bat_priv->gw.bandwidth_down, down_new); 213 atomic_set(&bat_priv->gw.bandwidth_up, up_new); 214 batadv_gw_tvlv_container_update(bat_priv); 215 216 return count; 217 } 218 219 /** 220 * batadv_gw_tvlv_ogm_handler_v1() - process incoming gateway tvlv container 221 * @bat_priv: the bat priv with all the soft interface information 222 * @orig: the orig_node of the ogm 223 * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags) 224 * @tvlv_value: tvlv buffer containing the gateway data 225 * @tvlv_value_len: tvlv buffer length 226 */ 227 static void batadv_gw_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv, 228 struct batadv_orig_node *orig, 229 u8 flags, 230 void *tvlv_value, u16 tvlv_value_len) 231 { 232 struct batadv_tvlv_gateway_data gateway, *gateway_ptr; 233 234 /* only fetch the tvlv value if the handler wasn't called via the 235 * CIFNOTFND flag and if there is data to fetch 236 */ 237 if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND || 238 tvlv_value_len < sizeof(gateway)) { 239 gateway.bandwidth_down = 0; 240 gateway.bandwidth_up = 0; 241 } else { 242 gateway_ptr = tvlv_value; 243 gateway.bandwidth_down = gateway_ptr->bandwidth_down; 244 gateway.bandwidth_up = gateway_ptr->bandwidth_up; 245 if (gateway.bandwidth_down == 0 || 246 gateway.bandwidth_up == 0) { 247 gateway.bandwidth_down = 0; 248 gateway.bandwidth_up = 0; 249 } 250 } 251 252 batadv_gw_node_update(bat_priv, orig, &gateway); 253 254 /* restart gateway selection */ 255 if (gateway.bandwidth_down != 0 && 256 atomic_read(&bat_priv->gw.mode) == BATADV_GW_MODE_CLIENT) 257 batadv_gw_check_election(bat_priv, orig); 258 } 259 260 /** 261 * batadv_gw_init() - initialise the gateway handling internals 262 * @bat_priv: the bat priv with all the soft interface information 263 */ 264 void batadv_gw_init(struct batadv_priv *bat_priv) 265 { 266 if (bat_priv->algo_ops->gw.init_sel_class) 267 bat_priv->algo_ops->gw.init_sel_class(bat_priv); 268 else 269 atomic_set(&bat_priv->gw.sel_class, 1); 270 271 batadv_tvlv_handler_register(bat_priv, batadv_gw_tvlv_ogm_handler_v1, 272 NULL, BATADV_TVLV_GW, 1, 273 BATADV_TVLV_HANDLER_OGM_CIFNOTFND); 274 } 275 276 /** 277 * batadv_gw_free() - free the gateway handling internals 278 * @bat_priv: the bat priv with all the soft interface information 279 */ 280 void batadv_gw_free(struct batadv_priv *bat_priv) 281 { 282 batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1); 283 batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_GW, 1); 284 } 285