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/math64.h> 15 #include <linux/netdevice.h> 16 #include <linux/stddef.h> 17 #include <linux/string.h> 18 #include <uapi/linux/batadv_packet.h> 19 #include <uapi/linux/batman_adv.h> 20 21 #include "gateway_client.h" 22 #include "log.h" 23 #include "tvlv.h" 24 25 /** 26 * batadv_parse_throughput() - parse supplied string buffer to extract 27 * throughput information 28 * @net_dev: the soft interface net device 29 * @buff: string buffer to parse 30 * @description: text shown when throughput string cannot be parsed 31 * @throughput: pointer holding the returned throughput information 32 * 33 * Return: false on parse error and true otherwise. 34 */ 35 bool batadv_parse_throughput(struct net_device *net_dev, char *buff, 36 const char *description, u32 *throughput) 37 { 38 enum batadv_bandwidth_units bw_unit_type = BATADV_BW_UNIT_KBIT; 39 u64 lthroughput; 40 char *tmp_ptr; 41 int ret; 42 43 if (strlen(buff) > 4) { 44 tmp_ptr = buff + strlen(buff) - 4; 45 46 if (strncasecmp(tmp_ptr, "mbit", 4) == 0) 47 bw_unit_type = BATADV_BW_UNIT_MBIT; 48 49 if (strncasecmp(tmp_ptr, "kbit", 4) == 0 || 50 bw_unit_type == BATADV_BW_UNIT_MBIT) 51 *tmp_ptr = '\0'; 52 } 53 54 ret = kstrtou64(buff, 10, <hroughput); 55 if (ret) { 56 batadv_err(net_dev, 57 "Invalid throughput speed for %s: %s\n", 58 description, buff); 59 return false; 60 } 61 62 switch (bw_unit_type) { 63 case BATADV_BW_UNIT_MBIT: 64 /* prevent overflow */ 65 if (U64_MAX / 10 < lthroughput) { 66 batadv_err(net_dev, 67 "Throughput speed for %s too large: %s\n", 68 description, buff); 69 return false; 70 } 71 72 lthroughput *= 10; 73 break; 74 case BATADV_BW_UNIT_KBIT: 75 default: 76 lthroughput = div_u64(lthroughput, 100); 77 break; 78 } 79 80 if (lthroughput > U32_MAX) { 81 batadv_err(net_dev, 82 "Throughput speed for %s too large: %s\n", 83 description, buff); 84 return false; 85 } 86 87 *throughput = lthroughput; 88 89 return true; 90 } 91 92 /** 93 * batadv_parse_gw_bandwidth() - parse supplied string buffer to extract 94 * download and upload bandwidth information 95 * @net_dev: the soft interface net device 96 * @buff: string buffer to parse 97 * @down: pointer holding the returned download bandwidth information 98 * @up: pointer holding the returned upload bandwidth information 99 * 100 * Return: false on parse error and true otherwise. 101 */ 102 static bool batadv_parse_gw_bandwidth(struct net_device *net_dev, char *buff, 103 u32 *down, u32 *up) 104 { 105 char *slash_ptr; 106 bool ret; 107 108 slash_ptr = strchr(buff, '/'); 109 if (slash_ptr) 110 *slash_ptr = 0; 111 112 ret = batadv_parse_throughput(net_dev, buff, "download gateway speed", 113 down); 114 if (!ret) 115 return false; 116 117 /* we also got some upload info */ 118 if (slash_ptr) { 119 ret = batadv_parse_throughput(net_dev, slash_ptr + 1, 120 "upload gateway speed", up); 121 if (!ret) 122 return false; 123 } 124 125 return true; 126 } 127 128 /** 129 * batadv_gw_tvlv_container_update() - update the gw tvlv container after 130 * gateway setting change 131 * @bat_priv: the bat priv with all the soft interface information 132 */ 133 void batadv_gw_tvlv_container_update(struct batadv_priv *bat_priv) 134 { 135 struct batadv_tvlv_gateway_data gw; 136 u32 down, up; 137 char gw_mode; 138 139 gw_mode = atomic_read(&bat_priv->gw.mode); 140 141 switch (gw_mode) { 142 case BATADV_GW_MODE_OFF: 143 case BATADV_GW_MODE_CLIENT: 144 batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1); 145 break; 146 case BATADV_GW_MODE_SERVER: 147 down = atomic_read(&bat_priv->gw.bandwidth_down); 148 up = atomic_read(&bat_priv->gw.bandwidth_up); 149 gw.bandwidth_down = htonl(down); 150 gw.bandwidth_up = htonl(up); 151 batadv_tvlv_container_register(bat_priv, BATADV_TVLV_GW, 1, 152 &gw, sizeof(gw)); 153 break; 154 } 155 } 156 157 /** 158 * batadv_gw_bandwidth_set() - Parse and set download/upload gateway bandwidth 159 * from supplied string buffer 160 * @net_dev: netdev struct of the soft interface 161 * @buff: the buffer containing the user data 162 * @count: number of bytes in the buffer 163 * 164 * Return: 'count' on success or a negative error code in case of failure 165 */ 166 ssize_t batadv_gw_bandwidth_set(struct net_device *net_dev, char *buff, 167 size_t count) 168 { 169 struct batadv_priv *bat_priv = netdev_priv(net_dev); 170 u32 down_curr; 171 u32 up_curr; 172 u32 down_new = 0; 173 u32 up_new = 0; 174 bool ret; 175 176 down_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_down); 177 up_curr = (unsigned int)atomic_read(&bat_priv->gw.bandwidth_up); 178 179 ret = batadv_parse_gw_bandwidth(net_dev, buff, &down_new, &up_new); 180 if (!ret) 181 return -EINVAL; 182 183 if (!down_new) 184 down_new = 1; 185 186 if (!up_new) 187 up_new = down_new / 5; 188 189 if (!up_new) 190 up_new = 1; 191 192 if (down_curr == down_new && up_curr == up_new) 193 return count; 194 195 batadv_gw_reselect(bat_priv); 196 batadv_info(net_dev, 197 "Changing gateway bandwidth from: '%u.%u/%u.%u MBit' to: '%u.%u/%u.%u MBit'\n", 198 down_curr / 10, down_curr % 10, up_curr / 10, up_curr % 10, 199 down_new / 10, down_new % 10, up_new / 10, up_new % 10); 200 201 atomic_set(&bat_priv->gw.bandwidth_down, down_new); 202 atomic_set(&bat_priv->gw.bandwidth_up, up_new); 203 batadv_gw_tvlv_container_update(bat_priv); 204 205 return count; 206 } 207 208 /** 209 * batadv_gw_tvlv_ogm_handler_v1() - process incoming gateway tvlv container 210 * @bat_priv: the bat priv with all the soft interface information 211 * @orig: the orig_node of the ogm 212 * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags) 213 * @tvlv_value: tvlv buffer containing the gateway data 214 * @tvlv_value_len: tvlv buffer length 215 */ 216 static void batadv_gw_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv, 217 struct batadv_orig_node *orig, 218 u8 flags, 219 void *tvlv_value, u16 tvlv_value_len) 220 { 221 struct batadv_tvlv_gateway_data gateway, *gateway_ptr; 222 223 /* only fetch the tvlv value if the handler wasn't called via the 224 * CIFNOTFND flag and if there is data to fetch 225 */ 226 if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND || 227 tvlv_value_len < sizeof(gateway)) { 228 gateway.bandwidth_down = 0; 229 gateway.bandwidth_up = 0; 230 } else { 231 gateway_ptr = tvlv_value; 232 gateway.bandwidth_down = gateway_ptr->bandwidth_down; 233 gateway.bandwidth_up = gateway_ptr->bandwidth_up; 234 if (gateway.bandwidth_down == 0 || 235 gateway.bandwidth_up == 0) { 236 gateway.bandwidth_down = 0; 237 gateway.bandwidth_up = 0; 238 } 239 } 240 241 batadv_gw_node_update(bat_priv, orig, &gateway); 242 243 /* restart gateway selection */ 244 if (gateway.bandwidth_down != 0 && 245 atomic_read(&bat_priv->gw.mode) == BATADV_GW_MODE_CLIENT) 246 batadv_gw_check_election(bat_priv, orig); 247 } 248 249 /** 250 * batadv_gw_init() - initialise the gateway handling internals 251 * @bat_priv: the bat priv with all the soft interface information 252 */ 253 void batadv_gw_init(struct batadv_priv *bat_priv) 254 { 255 if (bat_priv->algo_ops->gw.init_sel_class) 256 bat_priv->algo_ops->gw.init_sel_class(bat_priv); 257 else 258 atomic_set(&bat_priv->gw.sel_class, 1); 259 260 batadv_tvlv_handler_register(bat_priv, batadv_gw_tvlv_ogm_handler_v1, 261 NULL, BATADV_TVLV_GW, 1, 262 BATADV_TVLV_HANDLER_OGM_CIFNOTFND); 263 } 264 265 /** 266 * batadv_gw_free() - free the gateway handling internals 267 * @bat_priv: the bat priv with all the soft interface information 268 */ 269 void batadv_gw_free(struct batadv_priv *bat_priv) 270 { 271 batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_GW, 1); 272 batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_GW, 1); 273 } 274