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