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