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         char name[];
  80 };
  81
  82 static int
  83 bridge_disable_member(struct bridge_member *bm)
  84 {
  85         struct bridge_state *bst = bm->bst;
  86
  87         if (!bm->present)
  88                 return 0;
  89
  90         system_bridge_delif(&bst->dev, bm->dev.dev);
  91         device_release(&bm->dev);
  92
  93         return 0;
  94 }
  95
  96 static int
  97 bridge_enable_member(struct bridge_member *bm)
  98 {
  99         struct bridge_state *bst = bm->bst;
 100         int ret;
 101
 102         if (!bm->present)
 103                 return 0;
 104
 105         ret = device_claim(&bm->dev);
 106         if (ret < 0)
 107                 goto error;
 108
 109         ret = system_bridge_addif(&bst->dev, bm->dev.dev);
 110         if (ret < 0) {
 111                 D(DEVICE, "Bridge device %s could not be added\n", bm->dev.dev->ifname);
 112                 goto error;
 113         }
 114
 115         return 0;
 116
 117 error:
 118         bm->present = false;
 119         bst->n_present--;
 120         return ret;
 121 }
 122
 123 static void
 124 bridge_remove_member(struct bridge_member *bm)
 125 {
 126         struct bridge_state *bst = bm->bst;
 127
 128         if (!bm->present)
 129                 return;
 130
 131         bm->present = false;
 132         bm->bst->n_present--;
 133         if (bst->dev.active)
 134                 bridge_disable_member(bm);
 135
 136         bst->force_active = false;
 137         if (bst->n_present == 0)
 138                 device_set_present(&bst->dev, false);
 139 }
 140
 141 static void
 142 bridge_member_cb(struct device_user *dev, enum device_event ev)
 143 {
 144         struct bridge_member *bm = container_of(dev, struct bridge_member, dev);
 145         struct bridge_state *bst = bm->bst;
 146
 147         switch (ev) {
 148         case DEV_EVENT_ADD:
 149                 assert(!bm->present);
 150
 151                 bm->present = true;
 152                 bst->n_present++;
 153
 154                 if (bst->dev.active)
 155                         bridge_enable_member(bm);
 156                 else if (bst->n_present == 1)
 157                         device_set_present(&bst->dev, true);
 158
 159                 break;
 160         case DEV_EVENT_REMOVE:
 161                 if (dev->hotplug) {
 162                         vlist_delete(&bst->members, &bm->node);
 163                         return;
 164                 }
 165
 166                 if (bm->present)
 167                         bridge_remove_member(bm);
 168
 169                 break;
 170         default:
 171                 return;
 172         }
 173 }
 174
 175 static int
 176 bridge_set_down(struct bridge_state *bst)
 177 {
 178         struct bridge_member *bm;
 179
 180         bst->set_state(&bst->dev, false);
 181
 182         vlist_for_each_element(&bst->members, bm, node)
 183                 bridge_disable_member(bm);
 184
 185         system_bridge_delbr(&bst->dev);
 186
 187         return 0;
 188 }
 189
 190 static int
 191 bridge_set_up(struct bridge_state *bst)
 192 {
 193         struct bridge_member *bm;
 194         int ret;
 195
 196         if (!bst->force_active && !bst->n_present)
 197                 return -ENOENT;
 198
 199         ret = system_bridge_addbr(&bst->dev, &bst->config);
 200         if (ret < 0)
 201                 goto out;
 202
 203         vlist_for_each_element(&bst->members, bm, node)
 204                 bridge_enable_member(bm);
 205
 206         if (!bst->force_active && !bst->n_present) {
 207                 /* initialization of all member interfaces failed */
 208                 system_bridge_delbr(&bst->dev);
 209                 device_set_present(&bst->dev, false);
 210                 return -ENOENT;
 211         }
 212
 213         ret = bst->set_state(&bst->dev, true);
 214         if (ret < 0)
 215                 bridge_set_down(bst);
 216
 217 out:
 218         return ret;
 219 }
 220
 221 static int
 222 bridge_set_state(struct device *dev, bool up)
 223 {
 224         struct bridge_state *bst;
 225
 226         bst = container_of(dev, struct bridge_state, dev);
 227
 228         if (up)
 229                 return bridge_set_up(bst);
 230         else
 231                 return bridge_set_down(bst);
 232 }
 233
 234 static struct bridge_member *
 235 bridge_create_member(struct bridge_state *bst, struct device *dev, bool hotplug)
 236 {
 237         struct bridge_member *bm;
 238
 239         bm = calloc(1, sizeof(*bm) + strlen(dev->ifname) + 1);
 240         bm->bst = bst;
 241         bm->dev.cb = bridge_member_cb;
 242         bm->dev.hotplug = hotplug;
 243         strcpy(bm->name, dev->ifname);
 244         bm->dev.dev = dev;
 245         vlist_add(&bst->members, &bm->node, bm->name);
 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         struct device *dev;
 256
 257         if (node_new) {
 258                 bm = container_of(node_new, struct bridge_member, node);
 259
 260                 if (node_old) {
 261                         free(bm);
 262                         return;
 263                 }
 264
 265                 dev = bm->dev.dev;
 266                 bm->dev.dev = NULL;
 267                 device_add_user(&bm->dev, dev);
 268         }
 269
 270
 271         if (node_old) {
 272                 bm = container_of(node_old, struct bridge_member, node);
 273                 bridge_remove_member(bm);
 274                 device_remove_user(&bm->dev);
 275                 free(bm);
 276         }
 277 }
 278
 279
 280 static void
 281 bridge_add_member(struct bridge_state *bst, const char *name)
 282 {
 283         struct device *dev;
 284
 285         dev = device_get(name, true);
 286         if (!dev)
 287                 return;
 288
 289         bridge_create_member(bst, dev, false);
 290 }
 291
 292 static int
 293 bridge_hotplug_add(struct device *dev, struct device *member)
 294 {
 295         struct bridge_state *bst = container_of(dev, struct bridge_state, dev);
 296
 297         bridge_create_member(bst, member, true);
 298
 299         return 0;
 300 }
 301
 302 static int
 303 bridge_hotplug_del(struct device *dev, struct device *member)
 304 {
 305         struct bridge_state *bst = container_of(dev, struct bridge_state, dev);
 306         struct bridge_member *bm;
 307
 308         bm = vlist_find(&bst->members, member->ifname, bm, node);
 309         if (!bm)
 310                 return UBUS_STATUS_NOT_FOUND;
 311
 312         vlist_delete(&bst->members, &bm->node);
 313         return 0;
 314 }
 315
 316 static int
 317 bridge_hotplug_prepare(struct device *dev)
 318 {
 319         struct bridge_state *bst;
 320
 321         bst = container_of(dev, struct bridge_state, dev);
 322         bst->force_active = true;
 323         device_set_present(&bst->dev, true);
 324
 325         return 0;
 326 }
 327
 328 static const struct device_hotplug_ops bridge_ops = {
 329         .prepare = bridge_hotplug_prepare,
 330         .add = bridge_hotplug_add,
 331         .del = bridge_hotplug_del
 332 };
 333
 334 static void
 335 bridge_free(struct device *dev)
 336 {
 337         struct bridge_state *bst;
 338
 339         device_cleanup(dev);
 340         bst = container_of(dev, struct bridge_state, dev);
 341         vlist_flush_all(&bst->members);
 342         free(bst);
 343 }
 344
 345 static void
 346 bridge_dump_info(struct device *dev, struct blob_buf *b)
 347 {
 348         struct bridge_state *bst;
 349         struct bridge_member *bm;
 350         void *list;
 351
 352         bst = container_of(dev, struct bridge_state, dev);
 353
 354         system_if_dump_info(dev, b);
 355         list = blobmsg_open_array(b, "bridge-members");
 356
 357         vlist_for_each_element(&bst->members, bm, node)
 358                 blobmsg_add_string(b, NULL, bm->dev.dev->ifname);
 359
 360         blobmsg_close_array(b, list);
 361 }
 362
 363 static void
 364 bridge_config_init(struct device *dev)
 365 {
 366         struct bridge_state *bst;
 367         struct blob_attr *cur;
 368         int rem;
 369
 370         bst = container_of(dev, struct bridge_state, dev);
 371
 372         if (!bst->ifnames)
 373                 return;
 374
 375         blobmsg_for_each_attr(cur, bst->ifnames, rem) {
 376                 bridge_add_member(bst, blobmsg_data(cur));
 377         }
 378 }
 379
 380 static void
 381 bridge_apply_settings(struct bridge_state *bst, struct blob_attr **tb)
 382 {
 383         struct bridge_config *cfg = &bst->config;
 384         struct blob_attr *cur;
 385
 386         /* defaults */
 387         cfg->stp = true;
 388         cfg->forward_delay = 1;
 389         cfg->igmp_snoop = true;
 390
 391         if ((cur = tb[BRIDGE_ATTR_STP]))
 392                 cfg->stp = blobmsg_get_bool(cur);
 393
 394         if ((cur = tb[BRIDGE_ATTR_FORWARD_DELAY]))
 395                 cfg->forward_delay = blobmsg_get_u32(cur);
 396
 397         if ((cur = tb[BRIDGE_ATTR_IGMP_SNOOP]))
 398                 cfg->igmp_snoop = blobmsg_get_bool(cur);
 399
 400         if ((cur = tb[BRIDGE_ATTR_AGEING_TIME])) {
 401                 cfg->ageing_time = blobmsg_get_u32(cur);
 402                 cfg->flags |= BRIDGE_OPT_AGEING_TIME;
 403         }
 404
 405         if ((cur = tb[BRIDGE_ATTR_HELLO_TIME])) {
 406                 cfg->hello_time = blobmsg_get_u32(cur);
 407                 cfg->flags |= BRIDGE_OPT_HELLO_TIME;
 408         }
 409
 410         if ((cur = tb[BRIDGE_ATTR_MAX_AGE])) {
 411                 cfg->max_age = blobmsg_get_u32(cur);
 412                 cfg->flags |= BRIDGE_OPT_MAX_AGE;
 413         }
 414 }
 415
 416 static struct device *
 417 bridge_create(const char *name, struct blob_attr *attr)
 418 {
 419         struct blob_attr *tb_dev[__DEV_ATTR_MAX];
 420         struct blob_attr *tb_br[__BRIDGE_ATTR_MAX];
 421         struct bridge_state *bst;
 422         struct device *dev = NULL;
 423
 424         blobmsg_parse(device_attr_list.params, __DEV_ATTR_MAX, tb_dev,
 425                 blob_data(attr), blob_len(attr));
 426         blobmsg_parse(bridge_attrs, __BRIDGE_ATTR_MAX, tb_br,
 427                 blob_data(attr), blob_len(attr));
 428
 429         bst = calloc(1, sizeof(*bst));
 430         if (!bst)
 431                 return NULL;
 432
 433         dev = &bst->dev;
 434         device_init(dev, &bridge_device_type, name);
 435         device_init_settings(dev, tb_dev);
 436         dev->config_pending = true;
 437         bst->ifnames = tb_br[BRIDGE_ATTR_IFNAME];
 438         bridge_apply_settings(bst, tb_br);
 439
 440         bst->set_state = dev->set_state;
 441         dev->set_state = bridge_set_state;
 442
 443         dev->hotplug_ops = &bridge_ops;
 444
 445         vlist_init(&bst->members, avl_strcmp, bridge_member_update);
 446         bst->members.keep_old = true;
 447
 448         return dev;
 449 }
 450
 451