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
  51 const struct device_type bridge_device_type = {
  52         .name = "Bridge",
  53         .config_params = &bridge_attr_list,
  54
  55         .create = bridge_create,
  56         .config_init = bridge_config_init,
  57         .free = bridge_free,
  58         .dump_info = bridge_dump_info,
  59 };
  60
  61 struct bridge_state {
  62         struct device dev;
  63         device_state_cb set_state;
  64
  65         struct bridge_config config;
  66         struct blob_attr *ifnames;
  67         bool active;
  68         bool force_active;
  69
  70         struct vlist_tree members;
  71         int n_present;
  72 };
  73
  74 struct bridge_member {
  75         struct vlist_node node;
  76         struct bridge_state *bst;
  77         struct device_user dev;
  78         bool present;
  79 };
  80
  81 static int
  82 bridge_disable_member(struct bridge_member *bm)
  83 {
  84         struct bridge_state *bst = bm->bst;
  85
  86         if (!bm->present)
  87                 return 0;
  88
  89         system_bridge_delif(&bst->dev, bm->dev.dev);
  90         device_release(&bm->dev);
  91
  92         return 0;
  93 }
  94
  95 static int
  96 bridge_enable_member(struct bridge_member *bm)
  97 {
  98         struct bridge_state *bst = bm->bst;
  99         int ret;
 100
 101         if (!bm->present)
 102                 return 0;
 103
 104         ret = device_claim(&bm->dev);
 105         if (ret < 0)
 106                 goto error;
 107
 108         ret = system_bridge_addif(&bst->dev, bm->dev.dev);
 109         if (ret < 0)
 110                 goto error;
 111
 112         return 0;
 113
 114 error:
 115         bm->present = false;
 116         bst->n_present--;
 117         return ret;
 118 }
 119
 120 static void
 121 bridge_remove_member(struct bridge_member *bm)
 122 {
 123         struct bridge_state *bst = bm->bst;
 124
 125         if (!bm->present)
 126                 return;
 127
 128         bm->present = false;
 129         bm->bst->n_present--;
 130         if (bst->dev.active)
 131                 bridge_disable_member(bm);
 132
 133         bst->force_active = false;
 134         if (bst->n_present == 0)
 135                 device_set_present(&bst->dev, false);
 136 }
 137
 138 static void
 139 bridge_member_cb(struct device_user *dev, enum device_event ev)
 140 {
 141         struct bridge_member *bm = container_of(dev, struct bridge_member, dev);
 142         struct bridge_state *bst = bm->bst;
 143
 144         switch (ev) {
 145         case DEV_EVENT_ADD:
 146                 assert(!bm->present);
 147
 148                 bm->present = true;
 149                 bst->n_present++;
 150
 151                 if (bst->dev.active)
 152                         bridge_enable_member(bm);
 153                 else if (bst->n_present == 1)
 154                         device_set_present(&bst->dev, true);
 155
 156                 break;
 157         case DEV_EVENT_REMOVE:
 158                 if (!bm->present)
 159                         return;
 160
 161                 if (dev->hotplug)
 162                         vlist_delete(&bst->members, &bm->node);
 163                 else
 164                         bridge_remove_member(bm);
 165
 166                 break;
 167         default:
 168                 return;
 169         }
 170 }
 171
 172 static int
 173 bridge_set_down(struct bridge_state *bst)
 174 {
 175         struct bridge_member *bm;
 176
 177         bst->set_state(&bst->dev, false);
 178
 179         vlist_for_each_element(&bst->members, bm, node)
 180                 bridge_disable_member(bm);
 181
 182         system_bridge_delbr(&bst->dev);
 183
 184         return 0;
 185 }
 186
 187 static int
 188 bridge_set_up(struct bridge_state *bst)
 189 {
 190         struct bridge_member *bm;
 191         int ret;
 192
 193         if (!bst->force_active && !bst->n_present)
 194                 return -ENOENT;
 195
 196         ret = system_bridge_addbr(&bst->dev, &bst->config);
 197         if (ret < 0)
 198                 goto out;
 199
 200         vlist_for_each_element(&bst->members, bm, node)
 201                 bridge_enable_member(bm);
 202
 203         if (!bst->force_active && !bst->n_present) {
 204                 /* initialization of all member interfaces failed */
 205                 system_bridge_delbr(&bst->dev);
 206                 device_set_present(&bst->dev, false);
 207                 return -ENOENT;
 208         }
 209
 210         ret = bst->set_state(&bst->dev, true);
 211         if (ret < 0)
 212                 bridge_set_down(bst);
 213
 214 out:
 215         return ret;
 216 }
 217
 218 static int
 219 bridge_set_state(struct device *dev, bool up)
 220 {
 221         struct bridge_state *bst;
 222
 223         bst = container_of(dev, struct bridge_state, dev);
 224
 225         if (up)
 226                 return bridge_set_up(bst);
 227         else
 228                 return bridge_set_down(bst);
 229 }
 230
 231 static struct bridge_member *
 232 bridge_create_member(struct bridge_state *bst, struct device *dev, bool hotplug)
 233 {
 234         struct bridge_member *bm;
 235         char *name;
 236
 237         bm = calloc(1, sizeof(*bm) + strlen(dev->ifname) + 1);
 238         bm->bst = bst;
 239         bm->dev.cb = bridge_member_cb;
 240         bm->dev.hotplug = hotplug;
 241         name = (char *) (bm + 1);
 242         strcpy(name, dev->ifname);
 243         vlist_add(&bst->members, &bm->node, name);
 244
 245         device_add_user(&bm->dev, dev);
 246
 247         return bm;
 248 }
 249
 250 static void
 251 bridge_member_update(struct vlist_tree *tree, struct vlist_node *node_new,
 252                      struct vlist_node *node_old)
 253 {
 254         struct bridge_member *bm;
 255
 256         if (node_new && node_old)
 257                 return;
 258
 259         if (node_old) {
 260                 bm = container_of(node_old, struct bridge_member, node);
 261                 bridge_remove_member(bm);
 262                 device_remove_user(&bm->dev);
 263                 free(bm);
 264         }
 265 }
 266
 267
 268 static void
 269 bridge_add_member(struct bridge_state *bst, const char *name)
 270 {
 271         struct device *dev;
 272
 273         dev = device_get(name, true);
 274         if (!dev)
 275                 return;
 276
 277         bridge_create_member(bst, dev, false);
 278 }
 279
 280 static int
 281 bridge_hotplug_add(struct device *dev, struct device *member)
 282 {
 283         struct bridge_state *bst = container_of(dev, struct bridge_state, dev);
 284
 285         bridge_create_member(bst, member, true);
 286
 287         return 0;
 288 }
 289
 290 static int
 291 bridge_hotplug_del(struct device *dev, struct device *member)
 292 {
 293         struct bridge_state *bst = container_of(dev, struct bridge_state, dev);
 294         struct bridge_member *bm;
 295
 296         bm = vlist_find(&bst->members, member->ifname, bm, node);
 297         if (!bm)
 298                 return UBUS_STATUS_NOT_FOUND;
 299
 300         vlist_delete(&bst->members, &bm->node);
 301         return 0;
 302 }
 303
 304 static int
 305 bridge_hotplug_prepare(struct device *dev)
 306 {
 307         struct bridge_state *bst;
 308
 309         bst = container_of(dev, struct bridge_state, dev);
 310         bst->force_active = true;
 311         device_set_present(&bst->dev, true);
 312
 313         return 0;
 314 }
 315
 316 static const struct device_hotplug_ops bridge_ops = {
 317         .prepare = bridge_hotplug_prepare,
 318         .add = bridge_hotplug_add,
 319         .del = bridge_hotplug_del
 320 };
 321
 322 static void
 323 bridge_free(struct device *dev)
 324 {
 325         struct bridge_state *bst;
 326
 327         device_cleanup(dev);
 328         bst = container_of(dev, struct bridge_state, dev);
 329         vlist_flush_all(&bst->members);
 330         free(bst);
 331 }
 332
 333 static void
 334 bridge_dump_info(struct device *dev, struct blob_buf *b)
 335 {
 336         struct bridge_state *bst;
 337         struct bridge_member *bm;
 338         void *list;
 339
 340         bst = container_of(dev, struct bridge_state, dev);
 341
 342         system_if_dump_info(dev, b);
 343         list = blobmsg_open_array(b, "bridge-members");
 344
 345         vlist_for_each_element(&bst->members, bm, node)
 346                 blobmsg_add_string(b, NULL, bm->dev.dev->ifname);
 347
 348         blobmsg_close_array(b, list);
 349 }
 350
 351 static void
 352 bridge_config_init(struct device *dev)
 353 {
 354         struct bridge_state *bst;
 355         struct blob_attr *cur;
 356         int rem;
 357
 358         bst = container_of(dev, struct bridge_state, dev);
 359
 360         if (!bst->ifnames)
 361                 return;
 362
 363         blobmsg_for_each_attr(cur, bst->ifnames, rem) {
 364                 bridge_add_member(bst, blobmsg_data(cur));
 365         }
 366 }
 367
 368 static void
 369 bridge_apply_settings(struct bridge_state *bst, struct blob_attr **tb)
 370 {
 371         struct bridge_config *cfg = &bst->config;
 372         struct blob_attr *cur;
 373
 374         /* defaults */
 375         cfg->stp = true;
 376         cfg->forward_delay = 1;
 377         cfg->igmp_snoop = true;
 378
 379         if ((cur = tb[BRIDGE_ATTR_STP]))
 380                 cfg->stp = blobmsg_get_bool(cur);
 381
 382         if ((cur = tb[BRIDGE_ATTR_FORWARD_DELAY]))
 383                 cfg->forward_delay = blobmsg_get_u32(cur);
 384
 385         if ((cur = tb[BRIDGE_ATTR_IGMP_SNOOP]))
 386                 cfg->igmp_snoop = blobmsg_get_bool(cur);
 387
 388         if ((cur = tb[BRIDGE_ATTR_AGEING_TIME])) {
 389                 cfg->ageing_time = blobmsg_get_u32(cur);
 390                 cfg->flags |= BRIDGE_OPT_AGEING_TIME;
 391         }
 392
 393         if ((cur = tb[BRIDGE_ATTR_HELLO_TIME])) {
 394                 cfg->hello_time = blobmsg_get_u32(cur);
 395                 cfg->flags |= BRIDGE_OPT_HELLO_TIME;
 396         }
 397
 398         if ((cur = tb[BRIDGE_ATTR_MAX_AGE])) {
 399                 cfg->max_age = blobmsg_get_u32(cur);
 400                 cfg->flags |= BRIDGE_OPT_MAX_AGE;
 401         }
 402 }
 403
 404 static struct device *
 405 bridge_create(const char *name, struct blob_attr *attr)
 406 {
 407         struct blob_attr *tb_dev[__DEV_ATTR_MAX];
 408         struct blob_attr *tb_br[__BRIDGE_ATTR_MAX];
 409         struct bridge_state *bst;
 410         struct device *dev = NULL;
 411
 412         blobmsg_parse(device_attr_list.params, __DEV_ATTR_MAX, tb_dev,
 413                 blob_data(attr), blob_len(attr));
 414         blobmsg_parse(bridge_attrs, __BRIDGE_ATTR_MAX, tb_br,
 415                 blob_data(attr), blob_len(attr));
 416
 417         bst = calloc(1, sizeof(*bst));
 418         if (!bst)
 419                 return NULL;
 420
 421         dev = &bst->dev;
 422         device_init(dev, &bridge_device_type, name);
 423         device_init_settings(dev, tb_dev);
 424         dev->config_pending = true;
 425         bst->ifnames = tb_br[BRIDGE_ATTR_IFNAME];
 426         bridge_apply_settings(bst, tb_br);
 427
 428         bst->set_state = dev->set_state;
 429         dev->set_state = bridge_set_state;
 430
 431         dev->hotplug_ops = &bridge_ops;
 432
 433         vlist_init(&bst->members, avl_strcmp, bridge_member_update);
 434
 435         return dev;
 436 }
 437
 438