1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Copyright (C) 2005 Marc Kleine-Budde, Pengutronix 3 * Copyright (C) 2006 Andrey Volkov, Varma Electronics 4 * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com> 5 */ 6 7 #include <linux/can/dev.h> 8 #include <net/rtnetlink.h> 9 10 static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = { 11 [IFLA_CAN_STATE] = { .type = NLA_U32 }, 12 [IFLA_CAN_CTRLMODE] = { .len = sizeof(struct can_ctrlmode) }, 13 [IFLA_CAN_RESTART_MS] = { .type = NLA_U32 }, 14 [IFLA_CAN_RESTART] = { .type = NLA_U32 }, 15 [IFLA_CAN_BITTIMING] = { .len = sizeof(struct can_bittiming) }, 16 [IFLA_CAN_BITTIMING_CONST] 17 = { .len = sizeof(struct can_bittiming_const) }, 18 [IFLA_CAN_CLOCK] = { .len = sizeof(struct can_clock) }, 19 [IFLA_CAN_BERR_COUNTER] = { .len = sizeof(struct can_berr_counter) }, 20 [IFLA_CAN_DATA_BITTIMING] 21 = { .len = sizeof(struct can_bittiming) }, 22 [IFLA_CAN_DATA_BITTIMING_CONST] 23 = { .len = sizeof(struct can_bittiming_const) }, 24 [IFLA_CAN_TERMINATION] = { .type = NLA_U16 }, 25 }; 26 27 static int can_validate(struct nlattr *tb[], struct nlattr *data[], 28 struct netlink_ext_ack *extack) 29 { 30 bool is_can_fd = false; 31 32 /* Make sure that valid CAN FD configurations always consist of 33 * - nominal/arbitration bittiming 34 * - data bittiming 35 * - control mode with CAN_CTRLMODE_FD set 36 */ 37 38 if (!data) 39 return 0; 40 41 if (data[IFLA_CAN_CTRLMODE]) { 42 struct can_ctrlmode *cm = nla_data(data[IFLA_CAN_CTRLMODE]); 43 44 is_can_fd = cm->flags & cm->mask & CAN_CTRLMODE_FD; 45 } 46 47 if (is_can_fd) { 48 if (!data[IFLA_CAN_BITTIMING] || !data[IFLA_CAN_DATA_BITTIMING]) 49 return -EOPNOTSUPP; 50 } 51 52 if (data[IFLA_CAN_DATA_BITTIMING]) { 53 if (!is_can_fd || !data[IFLA_CAN_BITTIMING]) 54 return -EOPNOTSUPP; 55 } 56 57 return 0; 58 } 59 60 static int can_changelink(struct net_device *dev, struct nlattr *tb[], 61 struct nlattr *data[], 62 struct netlink_ext_ack *extack) 63 { 64 struct can_priv *priv = netdev_priv(dev); 65 int err; 66 67 /* We need synchronization with dev->stop() */ 68 ASSERT_RTNL(); 69 70 if (data[IFLA_CAN_BITTIMING]) { 71 struct can_bittiming bt; 72 73 /* Do not allow changing bittiming while running */ 74 if (dev->flags & IFF_UP) 75 return -EBUSY; 76 77 /* Calculate bittiming parameters based on 78 * bittiming_const if set, otherwise pass bitrate 79 * directly via do_set_bitrate(). Bail out if neither 80 * is given. 81 */ 82 if (!priv->bittiming_const && !priv->do_set_bittiming) 83 return -EOPNOTSUPP; 84 85 memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt)); 86 err = can_get_bittiming(dev, &bt, 87 priv->bittiming_const, 88 priv->bitrate_const, 89 priv->bitrate_const_cnt); 90 if (err) 91 return err; 92 93 if (priv->bitrate_max && bt.bitrate > priv->bitrate_max) { 94 netdev_err(dev, "arbitration bitrate surpasses transceiver capabilities of %d bps\n", 95 priv->bitrate_max); 96 return -EINVAL; 97 } 98 99 memcpy(&priv->bittiming, &bt, sizeof(bt)); 100 101 if (priv->do_set_bittiming) { 102 /* Finally, set the bit-timing registers */ 103 err = priv->do_set_bittiming(dev); 104 if (err) 105 return err; 106 } 107 } 108 109 if (data[IFLA_CAN_CTRLMODE]) { 110 struct can_ctrlmode *cm; 111 u32 ctrlstatic; 112 u32 maskedflags; 113 114 /* Do not allow changing controller mode while running */ 115 if (dev->flags & IFF_UP) 116 return -EBUSY; 117 cm = nla_data(data[IFLA_CAN_CTRLMODE]); 118 ctrlstatic = priv->ctrlmode_static; 119 maskedflags = cm->flags & cm->mask; 120 121 /* check whether provided bits are allowed to be passed */ 122 if (cm->mask & ~(priv->ctrlmode_supported | ctrlstatic)) 123 return -EOPNOTSUPP; 124 125 /* do not check for static fd-non-iso if 'fd' is disabled */ 126 if (!(maskedflags & CAN_CTRLMODE_FD)) 127 ctrlstatic &= ~CAN_CTRLMODE_FD_NON_ISO; 128 129 /* make sure static options are provided by configuration */ 130 if ((maskedflags & ctrlstatic) != ctrlstatic) 131 return -EOPNOTSUPP; 132 133 /* clear bits to be modified and copy the flag values */ 134 priv->ctrlmode &= ~cm->mask; 135 priv->ctrlmode |= maskedflags; 136 137 /* CAN_CTRLMODE_FD can only be set when driver supports FD */ 138 if (priv->ctrlmode & CAN_CTRLMODE_FD) 139 dev->mtu = CANFD_MTU; 140 else 141 dev->mtu = CAN_MTU; 142 } 143 144 if (data[IFLA_CAN_RESTART_MS]) { 145 /* Do not allow changing restart delay while running */ 146 if (dev->flags & IFF_UP) 147 return -EBUSY; 148 priv->restart_ms = nla_get_u32(data[IFLA_CAN_RESTART_MS]); 149 } 150 151 if (data[IFLA_CAN_RESTART]) { 152 /* Do not allow a restart while not running */ 153 if (!(dev->flags & IFF_UP)) 154 return -EINVAL; 155 err = can_restart_now(dev); 156 if (err) 157 return err; 158 } 159 160 if (data[IFLA_CAN_DATA_BITTIMING]) { 161 struct can_bittiming dbt; 162 163 /* Do not allow changing bittiming while running */ 164 if (dev->flags & IFF_UP) 165 return -EBUSY; 166 167 /* Calculate bittiming parameters based on 168 * data_bittiming_const if set, otherwise pass bitrate 169 * directly via do_set_bitrate(). Bail out if neither 170 * is given. 171 */ 172 if (!priv->data_bittiming_const && !priv->do_set_data_bittiming) 173 return -EOPNOTSUPP; 174 175 memcpy(&dbt, nla_data(data[IFLA_CAN_DATA_BITTIMING]), 176 sizeof(dbt)); 177 err = can_get_bittiming(dev, &dbt, 178 priv->data_bittiming_const, 179 priv->data_bitrate_const, 180 priv->data_bitrate_const_cnt); 181 if (err) 182 return err; 183 184 if (priv->bitrate_max && dbt.bitrate > priv->bitrate_max) { 185 netdev_err(dev, "canfd data bitrate surpasses transceiver capabilities of %d bps\n", 186 priv->bitrate_max); 187 return -EINVAL; 188 } 189 190 memcpy(&priv->data_bittiming, &dbt, sizeof(dbt)); 191 192 if (priv->do_set_data_bittiming) { 193 /* Finally, set the bit-timing registers */ 194 err = priv->do_set_data_bittiming(dev); 195 if (err) 196 return err; 197 } 198 } 199 200 if (data[IFLA_CAN_TERMINATION]) { 201 const u16 termval = nla_get_u16(data[IFLA_CAN_TERMINATION]); 202 const unsigned int num_term = priv->termination_const_cnt; 203 unsigned int i; 204 205 if (!priv->do_set_termination) 206 return -EOPNOTSUPP; 207 208 /* check whether given value is supported by the interface */ 209 for (i = 0; i < num_term; i++) { 210 if (termval == priv->termination_const[i]) 211 break; 212 } 213 if (i >= num_term) 214 return -EINVAL; 215 216 /* Finally, set the termination value */ 217 err = priv->do_set_termination(dev, termval); 218 if (err) 219 return err; 220 221 priv->termination = termval; 222 } 223 224 return 0; 225 } 226 227 static size_t can_get_size(const struct net_device *dev) 228 { 229 struct can_priv *priv = netdev_priv(dev); 230 size_t size = 0; 231 232 if (priv->bittiming.bitrate) /* IFLA_CAN_BITTIMING */ 233 size += nla_total_size(sizeof(struct can_bittiming)); 234 if (priv->bittiming_const) /* IFLA_CAN_BITTIMING_CONST */ 235 size += nla_total_size(sizeof(struct can_bittiming_const)); 236 size += nla_total_size(sizeof(struct can_clock)); /* IFLA_CAN_CLOCK */ 237 size += nla_total_size(sizeof(u32)); /* IFLA_CAN_STATE */ 238 size += nla_total_size(sizeof(struct can_ctrlmode)); /* IFLA_CAN_CTRLMODE */ 239 size += nla_total_size(sizeof(u32)); /* IFLA_CAN_RESTART_MS */ 240 if (priv->do_get_berr_counter) /* IFLA_CAN_BERR_COUNTER */ 241 size += nla_total_size(sizeof(struct can_berr_counter)); 242 if (priv->data_bittiming.bitrate) /* IFLA_CAN_DATA_BITTIMING */ 243 size += nla_total_size(sizeof(struct can_bittiming)); 244 if (priv->data_bittiming_const) /* IFLA_CAN_DATA_BITTIMING_CONST */ 245 size += nla_total_size(sizeof(struct can_bittiming_const)); 246 if (priv->termination_const) { 247 size += nla_total_size(sizeof(priv->termination)); /* IFLA_CAN_TERMINATION */ 248 size += nla_total_size(sizeof(*priv->termination_const) * /* IFLA_CAN_TERMINATION_CONST */ 249 priv->termination_const_cnt); 250 } 251 if (priv->bitrate_const) /* IFLA_CAN_BITRATE_CONST */ 252 size += nla_total_size(sizeof(*priv->bitrate_const) * 253 priv->bitrate_const_cnt); 254 if (priv->data_bitrate_const) /* IFLA_CAN_DATA_BITRATE_CONST */ 255 size += nla_total_size(sizeof(*priv->data_bitrate_const) * 256 priv->data_bitrate_const_cnt); 257 size += sizeof(priv->bitrate_max); /* IFLA_CAN_BITRATE_MAX */ 258 259 return size; 260 } 261 262 static int can_fill_info(struct sk_buff *skb, const struct net_device *dev) 263 { 264 struct can_priv *priv = netdev_priv(dev); 265 struct can_ctrlmode cm = {.flags = priv->ctrlmode}; 266 struct can_berr_counter bec; 267 enum can_state state = priv->state; 268 269 if (priv->do_get_state) 270 priv->do_get_state(dev, &state); 271 272 if ((priv->bittiming.bitrate && 273 nla_put(skb, IFLA_CAN_BITTIMING, 274 sizeof(priv->bittiming), &priv->bittiming)) || 275 276 (priv->bittiming_const && 277 nla_put(skb, IFLA_CAN_BITTIMING_CONST, 278 sizeof(*priv->bittiming_const), priv->bittiming_const)) || 279 280 nla_put(skb, IFLA_CAN_CLOCK, sizeof(priv->clock), &priv->clock) || 281 nla_put_u32(skb, IFLA_CAN_STATE, state) || 282 nla_put(skb, IFLA_CAN_CTRLMODE, sizeof(cm), &cm) || 283 nla_put_u32(skb, IFLA_CAN_RESTART_MS, priv->restart_ms) || 284 285 (priv->do_get_berr_counter && 286 !priv->do_get_berr_counter(dev, &bec) && 287 nla_put(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec)) || 288 289 (priv->data_bittiming.bitrate && 290 nla_put(skb, IFLA_CAN_DATA_BITTIMING, 291 sizeof(priv->data_bittiming), &priv->data_bittiming)) || 292 293 (priv->data_bittiming_const && 294 nla_put(skb, IFLA_CAN_DATA_BITTIMING_CONST, 295 sizeof(*priv->data_bittiming_const), 296 priv->data_bittiming_const)) || 297 298 (priv->termination_const && 299 (nla_put_u16(skb, IFLA_CAN_TERMINATION, priv->termination) || 300 nla_put(skb, IFLA_CAN_TERMINATION_CONST, 301 sizeof(*priv->termination_const) * 302 priv->termination_const_cnt, 303 priv->termination_const))) || 304 305 (priv->bitrate_const && 306 nla_put(skb, IFLA_CAN_BITRATE_CONST, 307 sizeof(*priv->bitrate_const) * 308 priv->bitrate_const_cnt, 309 priv->bitrate_const)) || 310 311 (priv->data_bitrate_const && 312 nla_put(skb, IFLA_CAN_DATA_BITRATE_CONST, 313 sizeof(*priv->data_bitrate_const) * 314 priv->data_bitrate_const_cnt, 315 priv->data_bitrate_const)) || 316 317 (nla_put(skb, IFLA_CAN_BITRATE_MAX, 318 sizeof(priv->bitrate_max), 319 &priv->bitrate_max)) 320 ) 321 322 return -EMSGSIZE; 323 324 return 0; 325 } 326 327 static size_t can_get_xstats_size(const struct net_device *dev) 328 { 329 return sizeof(struct can_device_stats); 330 } 331 332 static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev) 333 { 334 struct can_priv *priv = netdev_priv(dev); 335 336 if (nla_put(skb, IFLA_INFO_XSTATS, 337 sizeof(priv->can_stats), &priv->can_stats)) 338 goto nla_put_failure; 339 return 0; 340 341 nla_put_failure: 342 return -EMSGSIZE; 343 } 344 345 static int can_newlink(struct net *src_net, struct net_device *dev, 346 struct nlattr *tb[], struct nlattr *data[], 347 struct netlink_ext_ack *extack) 348 { 349 return -EOPNOTSUPP; 350 } 351 352 static void can_dellink(struct net_device *dev, struct list_head *head) 353 { 354 } 355 356 struct rtnl_link_ops can_link_ops __read_mostly = { 357 .kind = "can", 358 .maxtype = IFLA_CAN_MAX, 359 .policy = can_policy, 360 .setup = can_setup, 361 .validate = can_validate, 362 .newlink = can_newlink, 363 .changelink = can_changelink, 364 .dellink = can_dellink, 365 .get_size = can_get_size, 366 .fill_info = can_fill_info, 367 .get_xstats_size = can_get_xstats_size, 368 .fill_xstats = can_fill_xstats, 369 }; 370 371 int can_netlink_register(void) 372 { 373 return rtnl_link_register(&can_link_ops); 374 } 375 376 void can_netlink_unregister(void) 377 { 378 rtnl_link_unregister(&can_link_ops); 379 } 380