bridge.c

   1 #include <string.h>
   2 #include <stdlib.h>
   3 #include <stdio.h>
   4 #include <assert.h>
   5 #include <errno.h>
   6
   7 #include "netifd.h"
   8 #include "device.h"
   9 #include "interface.h"
  10 #include "system.h"
  11
  12 enum {
  13         BRIDGE_ATTR_IFNAME,
  14         BRIDGE_ATTR_STP,
  15         BRIDGE_ATTR_FORWARD_DELAY,
  16         BRIDGE_ATTR_IGMP_SNOOP,
  17         BRIDGE_ATTR_AGEING_TIME,
  18         BRIDGE_ATTR_HELLO_TIME,
  19         BRIDGE_ATTR_MAX_AGE,
  20         __BRIDGE_ATTR_MAX
  21 };
  22
  23 static const struct blobmsg_policy bridge_attrs[__BRIDGE_ATTR_MAX] = {
  24         [BRIDGE_ATTR_IFNAME] = { "ifname", BLOBMSG_TYPE_ARRAY },
  25         [BRIDGE_ATTR_STP] = { "stp", BLOBMSG_TYPE_BOOL },
  26         [BRIDGE_ATTR_FORWARD_DELAY] = { "forward_delay", BLOBMSG_TYPE_INT32 },
  27         [BRIDGE_ATTR_AGEING_TIME] = { "ageing_time", BLOBMSG_TYPE_INT32 },
  28         [BRIDGE_ATTR_HELLO_TIME] = { "hello_time", BLOBMSG_TYPE_INT32 },
  29         [BRIDGE_ATTR_MAX_AGE] = { "max_age", BLOBMSG_TYPE_INT32 },
  30         [BRIDGE_ATTR_IGMP_SNOOP] = { "igmp_snooping", BLOBMSG_TYPE_BOOL },
  31 };
  32
  33 static const union config_param_info bridge_attr_info[__BRIDGE_ATTR_MAX] = {
  34         [BRIDGE_ATTR_IFNAME] = { .type = BLOBMSG_TYPE_STRING },
  35 };
  36
  37 static const struct config_param_list bridge_attr_list = {
  38         .n_params = __BRIDGE_ATTR_MAX,
  39         .params = bridge_attrs,
  40         .info = bridge_attr_info,
  41
  42         .n_next = 1,
  43         .next = { &device_attr_list },
  44 };
  45
  46 static struct device *bridge_create(const char *name, struct blob_attr *attr);
  47 static void bridge_config_init(struct device *dev);
  48 static void bridge_free(struct device *dev);
  49 static void bridge_dump_info(struct device *dev, struct blob_buf *b);
  50 enum dev_change_type
  51 bridge_reload(struct device *dev, struct blob_attr *attr);
  52
  53 const struct device_type bridge_device_type = {
  54         .name = "Bridge",
  55         .config_params = &bridge_attr_list,
  56
  57         .create = bridge_create,
  58         .config_init = bridge_config_init,
  59         .reload = bridge_reload,
  60         .free = bridge_free,
  61         .dump_info = bridge_dump_info,
  62 };
  63
  64 struct bridge_state {
  65         struct device dev;
  66         device_state_cb set_state;
  67
  68         struct blob_attr *config_data;
  69         struct bridge_config config;
  70         struct blob_attr *ifnames;
  71         bool active;
  72         bool force_active;
  73
  74         struct vlist_tree members;
  75         int n_present;
  76 };
  77
  78 struct bridge_member {
  79         struct vlist_node node;
  80         struct bridge_state *bst;
  81         struct device_user dev;
  82         bool present;
  83         char name[];
  84 };
  85
  86 static int
  87 bridge_disable_member(struct bridge_member *bm)
  88 {
  89         struct bridge_state *bst = bm->bst;
  90
  91         if (!bm->present)
  92                 return 0;
  93
  94         system_bridge_delif(&bst->dev, bm->dev.dev);
  95         device_release(&bm->dev);
  96
  97         return 0;
  98 }
  99
 100 static int
 101 bridge_enable_member(struct bridge_member *bm)
 102 {
 103         struct bridge_state *bst = bm->bst;
 104         int ret;
 105
 106         if (!bm->present)
 107                 return 0;
 108
 109         ret = device_claim(&bm->dev);
 110         if (ret < 0)
 111                 goto error;
 112
 113         ret = system_bridge_addif(&bst->dev, bm->dev.dev);
 114         if (ret < 0) {
 115                 D(DEVICE, "Bridge device %s could not be added\n", bm->dev.dev->ifname);
 116                 goto error;
 117         }
 118
 119         return 0;
 120
 121 error:
 122         bm->present = false;
 123         bst->n_present--;
 124         return ret;
 125 }
 126
 127 static void
 128 bridge_remove_member(struct bridge_member *bm)
 129 {
 130         struct bridge_state *bst = bm->bst;
 131
 132         if (!bm->present)
 133                 return;
 134
 135         bm->present = false;
 136         bm->bst->n_present--;
 137         if (bst->dev.active)
 138                 bridge_disable_member(bm);
 139
 140         bst->force_active = false;
 141         if (bst->n_present == 0)
 142                 device_set_present(&bst->dev, false);
 143 }
 144
 145 static void
 146 bridge_member_cb(struct device_user *dev, enum device_event ev)
 147 {
 148         struct bridge_member *bm = container_of(dev, struct bridge_member, dev);
 149         struct bridge_state *bst = bm->bst;
 150
 151         switch (ev) {
 152         case DEV_EVENT_ADD:
 153                 assert(!bm->present);
 154
 155                 bm->present = true;
 156                 bst->n_present++;
 157
 158                 if (bst->dev.active)
 159                         bridge_enable_member(bm);
 160                 else if (bst->n_present == 1)
 161                         device_set_present(&bst->dev, true);
 162
 163                 break;
 164         case DEV_EVENT_REMOVE:
 165                 if (dev->hotplug) {
 166                         vlist_delete(&bst->members, &bm->node);
 167                         return;
 168                 }
 169
 170                 if (bm->present)
 171                         bridge_remove_member(bm);
 172
 173                 break;
 174         default:
 175                 return;
 176         }
 177 }
 178
 179 static int
 180 bridge_set_down(struct bridge_state *bst)
 181 {
 182         struct bridge_member *bm;
 183
 184         bst->set_state(&bst->dev, false);
 185
 186         vlist_for_each_element(&bst->members, bm, node)
 187                 bridge_disable_member(bm);
 188
 189         system_bridge_delbr(&bst->dev);
 190
 191         return 0;
 192 }
 193
 194 static int
 195 bridge_set_up(struct bridge_state *bst)
 196 {
 197         struct bridge_member *bm;
 198         int ret;
 199
 200         if (!bst->force_active && !bst->n_present)
 201                 return -ENOENT;
 202
 203         ret = system_bridge_addbr(&bst->dev, &bst->config);
 204         if (ret < 0)
 205                 goto out;
 206
 207         vlist_for_each_element(&bst->members, bm, node)
 208                 bridge_enable_member(bm);
 209
 210         if (!bst->force_active && !bst->n_present) {
 211                 /* initialization of all member interfaces failed */
 212                 system_bridge_delbr(&bst->dev);
 213                 device_set_present(&bst->dev, false);
 214                 return -ENOENT;
 215         }
 216
 217         ret = bst->set_state(&bst->dev, true);
 218         if (ret < 0)
 219                 bridge_set_down(bst);
 220
 221 out:
 222         return ret;
 223 }
 224
 225 static int
 226 bridge_set_state(struct device *dev, bool up)
 227 {
 228         struct bridge_state *bst;
 229
 230         bst = container_of(dev, struct bridge_state, dev);
 231
 232         if (up)
 233                 return bridge_set_up(bst);
 234         else
 235                 return bridge_set_down(bst);
 236 }
 237
 238 static struct bridge_member *
 239 bridge_create_member(struct bridge_state *bst, struct device *dev, bool hotplug)
 240 {
 241         struct bridge_member *bm;
 242
 243         bm = calloc(1, sizeof(*bm) + strlen(dev->ifname) + 1);
 244         bm->bst = bst;
 245         bm->dev.cb = bridge_member_cb;
 246         bm->dev.hotplug = hotplug;
 247         strcpy(bm->name, dev->ifname);
 248         bm->dev.dev = dev;
 249         vlist_add(&bst->members, &bm->node, bm->name);
 250         if (hotplug)
 251                 bm->node.version = -1;
 252
 253         return bm;
 254 }
 255
 256 static void
 257 bridge_member_update(struct vlist_tree *tree, struct vlist_node *node_new,
 258                      struct vlist_node *node_old)
 259 {
 260         struct bridge_member *bm;
 261         struct device *dev;
 262
 263         if (node_new) {
 264                 bm = container_of(node_new, struct bridge_member, node);
 265
 266                 if (node_old) {
 267                         free(bm);
 268                         return;
 269                 }
 270
 271                 dev = bm->dev.dev;
 272                 bm->dev.dev = NULL;
 273                 device_add_user(&bm->dev, dev);
 274         }
 275
 276
 277         if (node_old) {
 278                 bm = container_of(node_old, struct bridge_member, node);
 279                 bridge_remove_member(bm);
 280                 device_remove_user(&bm->dev);
 281                 free(bm);
 282         }
 283 }
 284
 285
 286 static void
 287 bridge_add_member(struct bridge_state *bst, const char *name)
 288 {
 289         struct device *dev;
 290
 291         dev = device_get(name, true);
 292         if (!dev)
 293                 return;
 294
 295         bridge_create_member(bst, dev, false);
 296 }
 297
 298 static int
 299 bridge_hotplug_add(struct device *dev, struct device *member)
 300 {
 301         struct bridge_state *bst = container_of(dev, struct bridge_state, dev);
 302
 303         bridge_create_member(bst, member, true);
 304
 305         return 0;
 306 }
 307
 308 static int
 309 bridge_hotplug_del(struct device *dev, struct device *member)
 310 {
 311         struct bridge_state *bst = container_of(dev, struct bridge_state, dev);
 312         struct bridge_member *bm;
 313
 314         bm = vlist_find(&bst->members, member->ifname, bm, node);
 315         if (!bm)
 316                 return UBUS_STATUS_NOT_FOUND;
 317
 318         vlist_delete(&bst->members, &bm->node);
 319         return 0;
 320 }
 321
 322 static int
 323 bridge_hotplug_prepare(struct device *dev)
 324 {
 325         struct bridge_state *bst;
 326
 327         bst = container_of(dev, struct bridge_state, dev);
 328         bst->force_active = true;
 329         device_set_present(&bst->dev, true);
 330
 331         return 0;
 332 }
 333
 334 static const struct device_hotplug_ops bridge_ops = {
 335         .prepare = bridge_hotplug_prepare,
 336         .add = bridge_hotplug_add,
 337         .del = bridge_hotplug_del
 338 };
 339
 340 static void
 341 bridge_free(struct device *dev)
 342 {
 343         struct bridge_state *bst;
 344
 345         device_cleanup(dev);
 346         bst = container_of(dev, struct bridge_state, dev);
 347         vlist_flush_all(&bst->members);
 348         free(bst);
 349 }
 350
 351 static void
 352 bridge_dump_info(struct device *dev, struct blob_buf *b)
 353 {
 354         struct bridge_state *bst;
 355         struct bridge_member *bm;
 356         void *list;
 357
 358         bst = container_of(dev, struct bridge_state, dev);
 359
 360         system_if_dump_info(dev, b);
 361         list = blobmsg_open_array(b, "bridge-members");
 362
 363         vlist_for_each_element(&bst->members, bm, node)
 364                 blobmsg_add_string(b, NULL, bm->dev.dev->ifname);
 365
 366         blobmsg_close_array(b, list);
 367 }
 368
 369 static void
 370 bridge_config_init(struct device *dev)
 371 {
 372         struct bridge_state *bst;
 373         struct blob_attr *cur;
 374         int rem;
 375
 376         bst = container_of(dev, struct bridge_state, dev);
 377
 378         if (!bst->ifnames)
 379                 return;
 380
 381         vlist_update(&bst->members);
 382         blobmsg_for_each_attr(cur, bst->ifnames, rem) {
 383                 bridge_add_member(bst, blobmsg_data(cur));
 384         }
 385         vlist_flush(&bst->members);
 386 }
 387
 388 static void
 389 bridge_apply_settings(struct bridge_state *bst, struct blob_attr **tb)
 390 {
 391         struct bridge_config *cfg = &bst->config;
 392         struct blob_attr *cur;
 393
 394         /* defaults */
 395         cfg->stp = true;
 396         cfg->forward_delay = 1;
 397         cfg->igmp_snoop = true;
 398
 399         if ((cur = tb[BRIDGE_ATTR_STP]))
 400                 cfg->stp = blobmsg_get_bool(cur);
 401
 402         if ((cur = tb[BRIDGE_ATTR_FORWARD_DELAY]))
 403                 cfg->forward_delay = blobmsg_get_u32(cur);
 404
 405         if ((cur = tb[BRIDGE_ATTR_IGMP_SNOOP]))
 406                 cfg->igmp_snoop = blobmsg_get_bool(cur);
 407
 408         if ((cur = tb[BRIDGE_ATTR_AGEING_TIME])) {
 409                 cfg->ageing_time = blobmsg_get_u32(cur);
 410                 cfg->flags |= BRIDGE_OPT_AGEING_TIME;
 411         }
 412
 413         if ((cur = tb[BRIDGE_ATTR_HELLO_TIME])) {
 414                 cfg->hello_time = blobmsg_get_u32(cur);
 415                 cfg->flags |= BRIDGE_OPT_HELLO_TIME;
 416         }
 417
 418         if ((cur = tb[BRIDGE_ATTR_MAX_AGE])) {
 419                 cfg->max_age = blobmsg_get_u32(cur);
 420                 cfg->flags |= BRIDGE_OPT_MAX_AGE;
 421         }
 422 }
 423
 424 enum dev_change_type
 425 bridge_reload(struct device *dev, struct blob_attr *attr)
 426 {
 427         struct blob_attr *tb_dev[__DEV_ATTR_MAX];
 428         struct blob_attr *tb_br[__BRIDGE_ATTR_MAX];
 429         enum dev_change_type ret = DEV_CONFIG_APPLIED;
 430         unsigned long diff;
 431         struct bridge_state *bst;
 432
 433         BUILD_BUG_ON(sizeof(diff) < __BRIDGE_ATTR_MAX / 8);
 434         BUILD_BUG_ON(sizeof(diff) < __DEV_ATTR_MAX / 8);
 435
 436         bst = container_of(dev, struct bridge_state, dev);
 437
 438         blobmsg_parse(device_attr_list.params, __DEV_ATTR_MAX, tb_dev,
 439                 blob_data(attr), blob_len(attr));
 440         blobmsg_parse(bridge_attrs, __BRIDGE_ATTR_MAX, tb_br,
 441                 blob_data(attr), blob_len(attr));
 442
 443         bst->ifnames = tb_br[BRIDGE_ATTR_IFNAME];
 444         device_init_settings(dev, tb_dev);
 445         bridge_apply_settings(bst, tb_br);
 446
 447         if (bst->config_data) {
 448                 struct blob_attr *otb_dev[__DEV_ATTR_MAX];
 449                 struct blob_attr *otb_br[__BRIDGE_ATTR_MAX];
 450
 451                 blobmsg_parse(device_attr_list.params, __DEV_ATTR_MAX, otb_dev,
 452                         blob_data(bst->config_data), blob_len(bst->config_data));
 453
 454                 diff = 0;
 455                 config_diff(tb_dev, otb_dev, &device_attr_list, &diff);
 456                 if (diff & ~(1 << DEV_ATTR_IFNAME))
 457                     ret = DEV_CONFIG_RESTART;
 458
 459                 blobmsg_parse(bridge_attrs, __BRIDGE_ATTR_MAX, otb_br,
 460                         blob_data(bst->config_data), blob_len(bst->config_data));
 461
 462                 diff = 0;
 463                 config_diff(tb_br, otb_br, &bridge_attr_list, &diff);
 464                 if (diff & ~(1 << BRIDGE_ATTR_IFNAME))
 465                     ret = DEV_CONFIG_RESTART;
 466
 467                 bridge_config_init(dev);
 468         }
 469
 470         bst->config_data = attr;
 471         return ret;
 472 }
 473
 474 static struct device *
 475 bridge_create(const char *name, struct blob_attr *attr)
 476 {
 477         struct bridge_state *bst;
 478         struct device *dev = NULL;
 479
 480         bst = calloc(1, sizeof(*bst));
 481         if (!bst)
 482                 return NULL;
 483
 484         dev = &bst->dev;
 485         device_init(dev, &bridge_device_type, name);
 486         dev->config_pending = true;
 487
 488         bst->set_state = dev->set_state;
 489         dev->set_state = bridge_set_state;
 490
 491         dev->hotplug_ops = &bridge_ops;
 492
 493         vlist_init(&bst->members, avl_strcmp, bridge_member_update);
 494         bst->members.keep_old = true;
 495         bridge_reload(dev, attr);
 496
 497         return dev;
 498 }
 499
 500