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         if (bst->dev.active)
 136                 bridge_disable_member(bm);
 137
 138         bm->present = false;
 139         bm->bst->n_present--;
 140
 141         bst->force_active = false;
 142         if (bst->n_present == 0)
 143                 device_set_present(&bst->dev, false);
 144 }
 145
 146 static void
 147 bridge_member_cb(struct device_user *dev, enum device_event ev)
 148 {
 149         struct bridge_member *bm = container_of(dev, struct bridge_member, dev);
 150         struct bridge_state *bst = bm->bst;
 151
 152         switch (ev) {
 153         case DEV_EVENT_ADD:
 154                 assert(!bm->present);
 155
 156                 bm->present = true;
 157                 bst->n_present++;
 158
 159                 if (bst->dev.active)
 160                         bridge_enable_member(bm);
 161                 else if (bst->n_present == 1)
 162                         device_set_present(&bst->dev, true);
 163
 164                 break;
 165         case DEV_EVENT_REMOVE:
 166                 if (dev->hotplug) {
 167                         vlist_delete(&bst->members, &bm->node);
 168                         return;
 169                 }
 170
 171                 if (bm->present)
 172                         bridge_remove_member(bm);
 173
 174                 break;
 175         default:
 176                 return;
 177         }
 178 }
 179
 180 static int
 181 bridge_set_down(struct bridge_state *bst)
 182 {
 183         struct bridge_member *bm;
 184
 185         bst->set_state(&bst->dev, false);
 186
 187         vlist_for_each_element(&bst->members, bm, node)
 188                 bridge_disable_member(bm);
 189
 190         system_bridge_delbr(&bst->dev);
 191
 192         return 0;
 193 }
 194
 195 static int
 196 bridge_set_up(struct bridge_state *bst)
 197 {
 198         struct bridge_member *bm;
 199         int ret;
 200
 201         if (!bst->force_active && !bst->n_present)
 202                 return -ENOENT;
 203
 204         ret = system_bridge_addbr(&bst->dev, &bst->config);
 205         if (ret < 0)
 206                 goto out;
 207
 208         vlist_for_each_element(&bst->members, bm, node)
 209                 bridge_enable_member(bm);
 210
 211         if (!bst->force_active && !bst->n_present) {
 212                 /* initialization of all member interfaces failed */
 213                 system_bridge_delbr(&bst->dev);
 214                 device_set_present(&bst->dev, false);
 215                 return -ENOENT;
 216         }
 217
 218         ret = bst->set_state(&bst->dev, true);
 219         if (ret < 0)
 220                 bridge_set_down(bst);
 221
 222 out:
 223         return ret;
 224 }
 225
 226 static int
 227 bridge_set_state(struct device *dev, bool up)
 228 {
 229         struct bridge_state *bst;
 230
 231         bst = container_of(dev, struct bridge_state, dev);
 232
 233         if (up)
 234                 return bridge_set_up(bst);
 235         else
 236                 return bridge_set_down(bst);
 237 }
 238
 239 static struct bridge_member *
 240 bridge_create_member(struct bridge_state *bst, struct device *dev, bool hotplug)
 241 {
 242         struct bridge_member *bm;
 243
 244         bm = calloc(1, sizeof(*bm) + strlen(dev->ifname) + 1);
 245         bm->bst = bst;
 246         bm->dev.cb = bridge_member_cb;
 247         bm->dev.hotplug = hotplug;
 248         strcpy(bm->name, dev->ifname);
 249         bm->dev.dev = dev;
 250         vlist_add(&bst->members, &bm->node, bm->name);
 251         if (hotplug)
 252                 bm->node.version = -1;
 253
 254         return bm;
 255 }
 256
 257 static void
 258 bridge_member_update(struct vlist_tree *tree, struct vlist_node *node_new,
 259                      struct vlist_node *node_old)
 260 {
 261         struct bridge_member *bm;
 262         struct device *dev;
 263
 264         if (node_new) {
 265                 bm = container_of(node_new, struct bridge_member, node);
 266
 267                 if (node_old) {
 268                         free(bm);
 269                         return;
 270                 }
 271
 272                 dev = bm->dev.dev;
 273                 bm->dev.dev = NULL;
 274                 device_add_user(&bm->dev, dev);
 275         }
 276
 277
 278         if (node_old) {
 279                 bm = container_of(node_old, struct bridge_member, node);
 280                 bridge_remove_member(bm);
 281                 device_remove_user(&bm->dev);
 282                 free(bm);
 283         }
 284 }
 285
 286
 287 static void
 288 bridge_add_member(struct bridge_state *bst, const char *name)
 289 {
 290         struct device *dev;
 291
 292         dev = device_get(name, true);
 293         if (!dev)
 294                 return;
 295
 296         bridge_create_member(bst, dev, false);
 297 }
 298
 299 static int
 300 bridge_hotplug_add(struct device *dev, struct device *member)
 301 {
 302         struct bridge_state *bst = container_of(dev, struct bridge_state, dev);
 303
 304         bridge_create_member(bst, member, true);
 305
 306         return 0;
 307 }
 308
 309 static int
 310 bridge_hotplug_del(struct device *dev, struct device *member)
 311 {
 312         struct bridge_state *bst = container_of(dev, struct bridge_state, dev);
 313         struct bridge_member *bm;
 314
 315         bm = vlist_find(&bst->members, member->ifname, bm, node);
 316         if (!bm)
 317                 return UBUS_STATUS_NOT_FOUND;
 318
 319         vlist_delete(&bst->members, &bm->node);
 320         return 0;
 321 }
 322
 323 static int
 324 bridge_hotplug_prepare(struct device *dev)
 325 {
 326         struct bridge_state *bst;
 327
 328         bst = container_of(dev, struct bridge_state, dev);
 329         bst->force_active = true;
 330         device_set_present(&bst->dev, true);
 331
 332         return 0;
 333 }
 334
 335 static const struct device_hotplug_ops bridge_ops = {
 336         .prepare = bridge_hotplug_prepare,
 337         .add = bridge_hotplug_add,
 338         .del = bridge_hotplug_del
 339 };
 340
 341 static void
 342 bridge_free(struct device *dev)
 343 {
 344         struct bridge_state *bst;
 345
 346         device_cleanup(dev);
 347         bst = container_of(dev, struct bridge_state, dev);
 348         vlist_flush_all(&bst->members);
 349         free(bst);
 350 }
 351
 352 static void
 353 bridge_dump_info(struct device *dev, struct blob_buf *b)
 354 {
 355         struct bridge_state *bst;
 356         struct bridge_member *bm;
 357         void *list;
 358
 359         bst = container_of(dev, struct bridge_state, dev);
 360
 361         system_if_dump_info(dev, b);
 362         list = blobmsg_open_array(b, "bridge-members");
 363
 364         vlist_for_each_element(&bst->members, bm, node)
 365                 blobmsg_add_string(b, NULL, bm->dev.dev->ifname);
 366
 367         blobmsg_close_array(b, list);
 368 }
 369
 370 static void
 371 bridge_config_init(struct device *dev)
 372 {
 373         struct bridge_state *bst;
 374         struct blob_attr *cur;
 375         int rem;
 376
 377         bst = container_of(dev, struct bridge_state, dev);
 378
 379         if (!bst->ifnames)
 380                 return;
 381
 382         vlist_update(&bst->members);
 383         blobmsg_for_each_attr(cur, bst->ifnames, rem) {
 384                 bridge_add_member(bst, blobmsg_data(cur));
 385         }
 386         vlist_flush(&bst->members);
 387 }
 388
 389 static void
 390 bridge_apply_settings(struct bridge_state *bst, struct blob_attr **tb)
 391 {
 392         struct bridge_config *cfg = &bst->config;
 393         struct blob_attr *cur;
 394
 395         /* defaults */
 396         cfg->stp = false;
 397         cfg->forward_delay = 2;
 398         cfg->igmp_snoop = true;
 399
 400         if ((cur = tb[BRIDGE_ATTR_STP]))
 401                 cfg->stp = blobmsg_get_bool(cur);
 402
 403         if ((cur = tb[BRIDGE_ATTR_FORWARD_DELAY]))
 404                 cfg->forward_delay = blobmsg_get_u32(cur);
 405
 406         if ((cur = tb[BRIDGE_ATTR_IGMP_SNOOP]))
 407                 cfg->igmp_snoop = blobmsg_get_bool(cur);
 408
 409         if ((cur = tb[BRIDGE_ATTR_AGEING_TIME])) {
 410                 cfg->ageing_time = blobmsg_get_u32(cur);
 411                 cfg->flags |= BRIDGE_OPT_AGEING_TIME;
 412         }
 413
 414         if ((cur = tb[BRIDGE_ATTR_HELLO_TIME])) {
 415                 cfg->hello_time = blobmsg_get_u32(cur);
 416                 cfg->flags |= BRIDGE_OPT_HELLO_TIME;
 417         }
 418
 419         if ((cur = tb[BRIDGE_ATTR_MAX_AGE])) {
 420                 cfg->max_age = blobmsg_get_u32(cur);
 421                 cfg->flags |= BRIDGE_OPT_MAX_AGE;
 422         }
 423 }
 424
 425 enum dev_change_type
 426 bridge_reload(struct device *dev, struct blob_attr *attr)
 427 {
 428         struct blob_attr *tb_dev[__DEV_ATTR_MAX];
 429         struct blob_attr *tb_br[__BRIDGE_ATTR_MAX];
 430         enum dev_change_type ret = DEV_CONFIG_APPLIED;
 431         unsigned long diff;
 432         struct bridge_state *bst;
 433
 434         BUILD_BUG_ON(sizeof(diff) < __BRIDGE_ATTR_MAX / 8);
 435         BUILD_BUG_ON(sizeof(diff) < __DEV_ATTR_MAX / 8);
 436
 437         bst = container_of(dev, struct bridge_state, dev);
 438
 439         blobmsg_parse(device_attr_list.params, __DEV_ATTR_MAX, tb_dev,
 440                 blob_data(attr), blob_len(attr));
 441         blobmsg_parse(bridge_attrs, __BRIDGE_ATTR_MAX, tb_br,
 442                 blob_data(attr), blob_len(attr));
 443
 444         bst->ifnames = tb_br[BRIDGE_ATTR_IFNAME];
 445         device_init_settings(dev, tb_dev);
 446         bridge_apply_settings(bst, tb_br);
 447
 448         if (bst->config_data) {
 449                 struct blob_attr *otb_dev[__DEV_ATTR_MAX];
 450                 struct blob_attr *otb_br[__BRIDGE_ATTR_MAX];
 451
 452                 blobmsg_parse(device_attr_list.params, __DEV_ATTR_MAX, otb_dev,
 453                         blob_data(bst->config_data), blob_len(bst->config_data));
 454
 455                 diff = 0;
 456                 config_diff(tb_dev, otb_dev, &device_attr_list, &diff);
 457                 if (diff & ~(1 << DEV_ATTR_IFNAME))
 458                     ret = DEV_CONFIG_RESTART;
 459
 460                 blobmsg_parse(bridge_attrs, __BRIDGE_ATTR_MAX, otb_br,
 461                         blob_data(bst->config_data), blob_len(bst->config_data));
 462
 463                 diff = 0;
 464                 config_diff(tb_br, otb_br, &bridge_attr_list, &diff);
 465                 if (diff & ~(1 << BRIDGE_ATTR_IFNAME))
 466                     ret = DEV_CONFIG_RESTART;
 467
 468                 bridge_config_init(dev);
 469         }
 470
 471         bst->config_data = attr;
 472         return ret;
 473 }
 474
 475 static struct device *
 476 bridge_create(const char *name, struct blob_attr *attr)
 477 {
 478         struct bridge_state *bst;
 479         struct device *dev = NULL;
 480
 481         bst = calloc(1, sizeof(*bst));
 482         if (!bst)
 483                 return NULL;
 484
 485         dev = &bst->dev;
 486         device_init(dev, &bridge_device_type, name);
 487         dev->config_pending = true;
 488
 489         bst->set_state = dev->set_state;
 490         dev->set_state = bridge_set_state;
 491
 492         dev->hotplug_ops = &bridge_ops;
 493
 494         vlist_init(&bst->members, avl_strcmp, bridge_member_update);
 495         bst->members.keep_old = true;
 496         bridge_reload(dev, attr);
 497
 498         return dev;
 499 }
 500
 501