1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (C) 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 */ 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 */ 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 */ 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 */ 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 */ 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 */ 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 */ 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