bridge.c

   1 /*
   2  * netifd - network interface daemon
   3  * Copyright (C) 2012 Felix Fietkau <nbd@openwrt.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2
   7  * as published by the Free Software Foundation
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14 #include <string.h>
  15 #include <stdlib.h>
  16 #include <stdio.h>
  17 #include <assert.h>
  18 #include <errno.h>
  19
  20 #include "netifd.h"
  21 #include "device.h"
  22 #include "interface.h"
  23 #include "system.h"
  24
  25 enum {
  26         BRIDGE_ATTR_IFNAME,
  27         BRIDGE_ATTR_STP,
  28         BRIDGE_ATTR_FORWARD_DELAY,
  29         BRIDGE_ATTR_IGMP_SNOOP,
  30         BRIDGE_ATTR_AGEING_TIME,
  31         BRIDGE_ATTR_HELLO_TIME,
  32         BRIDGE_ATTR_MAX_AGE,
  33         __BRIDGE_ATTR_MAX
  34 };
  35
  36 static const struct blobmsg_policy bridge_attrs[__BRIDGE_ATTR_MAX] = {
  37         [BRIDGE_ATTR_IFNAME] = { "ifname", BLOBMSG_TYPE_ARRAY },
  38         [BRIDGE_ATTR_STP] = { "stp", BLOBMSG_TYPE_BOOL },
  39         [BRIDGE_ATTR_FORWARD_DELAY] = { "forward_delay", BLOBMSG_TYPE_INT32 },
  40         [BRIDGE_ATTR_AGEING_TIME] = { "ageing_time", BLOBMSG_TYPE_INT32 },
  41         [BRIDGE_ATTR_HELLO_TIME] = { "hello_time", BLOBMSG_TYPE_INT32 },
  42         [BRIDGE_ATTR_MAX_AGE] = { "max_age", BLOBMSG_TYPE_INT32 },
  43         [BRIDGE_ATTR_IGMP_SNOOP] = { "igmp_snooping", BLOBMSG_TYPE_BOOL },
  44 };
  45
  46 static const union config_param_info bridge_attr_info[__BRIDGE_ATTR_MAX] = {
  47         [BRIDGE_ATTR_IFNAME] = { .type = BLOBMSG_TYPE_STRING },
  48 };
  49
  50 static const struct config_param_list bridge_attr_list = {
  51         .n_params = __BRIDGE_ATTR_MAX,
  52         .params = bridge_attrs,
  53         .info = bridge_attr_info,
  54
  55         .n_next = 1,
  56         .next = { &device_attr_list },
  57 };
  58
  59 static struct device *bridge_create(const char *name, struct blob_attr *attr);
  60 static void bridge_config_init(struct device *dev);
  61 static void bridge_free(struct device *dev);
  62 static void bridge_dump_info(struct device *dev, struct blob_buf *b);
  63 enum dev_change_type
  64 bridge_reload(struct device *dev, struct blob_attr *attr);
  65
  66 const struct device_type bridge_device_type = {
  67         .name = "Bridge",
  68         .config_params = &bridge_attr_list,
  69
  70         .create = bridge_create,
  71         .config_init = bridge_config_init,
  72         .reload = bridge_reload,
  73         .free = bridge_free,
  74         .dump_info = bridge_dump_info,
  75 };
  76
  77 struct bridge_state {
  78         struct device dev;
  79         device_state_cb set_state;
  80
  81         struct blob_attr *config_data;
  82         struct bridge_config config;
  83         struct blob_attr *ifnames;
  84         bool active;
  85         bool force_active;
  86
  87         struct bridge_member *primary_port;
  88         struct vlist_tree members;
  89         int n_present;
  90 };
  91
  92 struct bridge_member {
  93         struct vlist_node node;
  94         struct bridge_state *bst;
  95         struct device_user dev;
  96         bool present;
  97         char name[];
  98 };
  99
 100 static void
 101 bridge_reset_primary(struct bridge_state *bst)
 102 {
 103         struct bridge_member *bm;
 104
 105         if (!bst->primary_port &&
 106             (bst->dev.settings.flags & DEV_OPT_MACADDR))
 107                 return;
 108
 109         bst->primary_port = NULL;
 110         bst->dev.settings.flags &= ~DEV_OPT_MACADDR;
 111         vlist_for_each_element(&bst->members, bm, node) {
 112                 uint8_t *macaddr;
 113
 114                 if (!bm->present)
 115                         continue;
 116
 117                 bst->primary_port = bm;
 118                 if (bm->dev.dev->settings.flags & DEV_OPT_MACADDR)
 119                         macaddr = bm->dev.dev->settings.macaddr;
 120                 else
 121                         macaddr = bm->dev.dev->orig_settings.macaddr;
 122                 memcpy(bst->dev.settings.macaddr, macaddr, 6);
 123                 bst->dev.settings.flags |= DEV_OPT_MACADDR;
 124                 return;
 125         }
 126 }
 127
 128 static int
 129 bridge_disable_member(struct bridge_member *bm)
 130 {
 131         struct bridge_state *bst = bm->bst;
 132
 133         if (!bm->present)
 134                 return 0;
 135
 136         system_bridge_delif(&bst->dev, bm->dev.dev);
 137         device_release(&bm->dev);
 138
 139         return 0;
 140 }
 141
 142 static int
 143 bridge_enable_member(struct bridge_member *bm)
 144 {
 145         struct bridge_state *bst = bm->bst;
 146         int ret;
 147
 148         if (!bm->present)
 149                 return 0;
 150
 151         ret = device_claim(&bm->dev);
 152         if (ret < 0)
 153                 goto error;
 154
 155         ret = system_bridge_addif(&bst->dev, bm->dev.dev);
 156         if (ret < 0) {
 157                 D(DEVICE, "Bridge device %s could not be added\n", bm->dev.dev->ifname);
 158                 goto error;
 159         }
 160
 161         return 0;
 162
 163 error:
 164         bm->present = false;
 165         bst->n_present--;
 166         return ret;
 167 }
 168
 169 static void
 170 bridge_remove_member(struct bridge_member *bm)
 171 {
 172         struct bridge_state *bst = bm->bst;
 173
 174         if (!bm->present)
 175                 return;
 176
 177         if (bm == bst->primary_port);
 178                 bridge_reset_primary(bst);
 179
 180         if (bst->dev.active)
 181                 bridge_disable_member(bm);
 182
 183         bm->present = false;
 184         bm->bst->n_present--;
 185
 186         bst->force_active = false;
 187         if (bst->n_present == 0)
 188                 device_set_present(&bst->dev, false);
 189 }
 190
 191 static void
 192 bridge_free_member(struct bridge_member *bm)
 193 {
 194         struct device *dev = bm->dev.dev;
 195
 196         bridge_remove_member(bm);
 197         device_remove_user(&bm->dev);
 198
 199         /*
 200          * When reloading the config and moving a device from one bridge to
 201          * another, the other bridge may have tried to claim this device
 202          * before it was removed here.
 203          * Ensure that claiming the device is retried by toggling its present
 204          * state
 205          */
 206         if (dev->present) {
 207                 device_set_present(dev, false);
 208                 device_set_present(dev, true);
 209         }
 210
 211         free(bm);
 212 }
 213
 214 static void
 215 bridge_member_cb(struct device_user *dev, enum device_event ev)
 216 {
 217         struct bridge_member *bm = container_of(dev, struct bridge_member, dev);
 218         struct bridge_state *bst = bm->bst;
 219
 220         switch (ev) {
 221         case DEV_EVENT_ADD:
 222                 assert(!bm->present);
 223
 224                 bm->present = true;
 225                 bst->n_present++;
 226
 227                 if (bst->dev.active)
 228                         bridge_enable_member(bm);
 229                 else if (bst->n_present == 1)
 230                         device_set_present(&bst->dev, true);
 231
 232                 break;
 233         case DEV_EVENT_REMOVE:
 234                 if (dev->hotplug) {
 235                         vlist_delete(&bst->members, &bm->node);
 236                         return;
 237                 }
 238
 239                 if (bm->present)
 240                         bridge_remove_member(bm);
 241
 242                 break;
 243         default:
 244                 return;
 245         }
 246 }
 247
 248 static int
 249 bridge_set_down(struct bridge_state *bst)
 250 {
 251         struct bridge_member *bm;
 252
 253         bst->set_state(&bst->dev, false);
 254
 255         vlist_for_each_element(&bst->members, bm, node)
 256                 bridge_disable_member(bm);
 257
 258         system_bridge_delbr(&bst->dev);
 259
 260         return 0;
 261 }
 262
 263 static int
 264 bridge_set_up(struct bridge_state *bst)
 265 {
 266         struct bridge_member *bm;
 267         int ret;
 268
 269         if (!bst->force_active && !bst->n_present)
 270                 return -ENOENT;
 271
 272         ret = system_bridge_addbr(&bst->dev, &bst->config);
 273         if (ret < 0)
 274                 goto out;
 275
 276         vlist_for_each_element(&bst->members, bm, node)
 277                 bridge_enable_member(bm);
 278
 279         if (!bst->force_active && !bst->n_present) {
 280                 /* initialization of all member interfaces failed */
 281                 system_bridge_delbr(&bst->dev);
 282                 device_set_present(&bst->dev, false);
 283                 return -ENOENT;
 284         }
 285
 286         bridge_reset_primary(bst);
 287         ret = bst->set_state(&bst->dev, true);
 288         if (ret < 0)
 289                 bridge_set_down(bst);
 290
 291 out:
 292         return ret;
 293 }
 294
 295 static int
 296 bridge_set_state(struct device *dev, bool up)
 297 {
 298         struct bridge_state *bst;
 299
 300         bst = container_of(dev, struct bridge_state, dev);
 301
 302         if (up)
 303                 return bridge_set_up(bst);
 304         else
 305                 return bridge_set_down(bst);
 306 }
 307
 308 static struct bridge_member *
 309 bridge_create_member(struct bridge_state *bst, struct device *dev, bool hotplug)
 310 {
 311         struct bridge_member *bm;
 312
 313         bm = calloc(1, sizeof(*bm) + strlen(dev->ifname) + 1);
 314         bm->bst = bst;
 315         bm->dev.cb = bridge_member_cb;
 316         bm->dev.hotplug = hotplug;
 317         strcpy(bm->name, dev->ifname);
 318         bm->dev.dev = dev;
 319         vlist_add(&bst->members, &bm->node, bm->name);
 320         if (hotplug)
 321                 bm->node.version = -1;
 322
 323         return bm;
 324 }
 325
 326 static void
 327 bridge_member_update(struct vlist_tree *tree, struct vlist_node *node_new,
 328                      struct vlist_node *node_old)
 329 {
 330         struct bridge_member *bm;
 331         struct device *dev;
 332
 333         if (node_new) {
 334                 bm = container_of(node_new, struct bridge_member, node);
 335
 336                 if (node_old) {
 337                         free(bm);
 338                         return;
 339                 }
 340
 341                 dev = bm->dev.dev;
 342                 bm->dev.dev = NULL;
 343                 device_add_user(&bm->dev, dev);
 344         }
 345
 346
 347         if (node_old) {
 348                 bm = container_of(node_old, struct bridge_member, node);
 349                 bridge_free_member(bm);
 350         }
 351 }
 352
 353
 354 static void
 355 bridge_add_member(struct bridge_state *bst, const char *name)
 356 {
 357         struct device *dev;
 358
 359         dev = device_get(name, true);
 360         if (!dev)
 361                 return;
 362
 363         bridge_create_member(bst, dev, false);
 364 }
 365
 366 static int
 367 bridge_hotplug_add(struct device *dev, struct device *member)
 368 {
 369         struct bridge_state *bst = container_of(dev, struct bridge_state, dev);
 370
 371         bridge_create_member(bst, member, true);
 372
 373         return 0;
 374 }
 375
 376 static int
 377 bridge_hotplug_del(struct device *dev, struct device *member)
 378 {
 379         struct bridge_state *bst = container_of(dev, struct bridge_state, dev);
 380         struct bridge_member *bm;
 381
 382         bm = vlist_find(&bst->members, member->ifname, bm, node);
 383         if (!bm)
 384                 return UBUS_STATUS_NOT_FOUND;
 385
 386         vlist_delete(&bst->members, &bm->node);
 387         return 0;
 388 }
 389
 390 static int
 391 bridge_hotplug_prepare(struct device *dev)
 392 {
 393         struct bridge_state *bst;
 394
 395         bst = container_of(dev, struct bridge_state, dev);
 396         bst->force_active = true;
 397         device_set_present(&bst->dev, true);
 398
 399         return 0;
 400 }
 401
 402 static const struct device_hotplug_ops bridge_ops = {
 403         .prepare = bridge_hotplug_prepare,
 404         .add = bridge_hotplug_add,
 405         .del = bridge_hotplug_del
 406 };
 407
 408 static void
 409 bridge_free(struct device *dev)
 410 {
 411         struct bridge_state *bst;
 412
 413         bst = container_of(dev, struct bridge_state, dev);
 414         vlist_flush_all(&bst->members);
 415         free(bst);
 416 }
 417
 418 static void
 419 bridge_dump_info(struct device *dev, struct blob_buf *b)
 420 {
 421         struct bridge_state *bst;
 422         struct bridge_member *bm;
 423         void *list;
 424
 425         bst = container_of(dev, struct bridge_state, dev);
 426
 427         system_if_dump_info(dev, b);
 428         list = blobmsg_open_array(b, "bridge-members");
 429
 430         vlist_for_each_element(&bst->members, bm, node)
 431                 blobmsg_add_string(b, NULL, bm->dev.dev->ifname);
 432
 433         blobmsg_close_array(b, list);
 434 }
 435
 436 static void
 437 bridge_config_init(struct device *dev)
 438 {
 439         struct bridge_state *bst;
 440         struct blob_attr *cur;
 441         int rem;
 442
 443         bst = container_of(dev, struct bridge_state, dev);
 444
 445         if (!bst->ifnames)
 446                 return;
 447
 448         vlist_update(&bst->members);
 449         blobmsg_for_each_attr(cur, bst->ifnames, rem) {
 450                 bridge_add_member(bst, blobmsg_data(cur));
 451         }
 452         vlist_flush(&bst->members);
 453 }
 454
 455 static void
 456 bridge_apply_settings(struct bridge_state *bst, struct blob_attr **tb)
 457 {
 458         struct bridge_config *cfg = &bst->config;
 459         struct blob_attr *cur;
 460
 461         /* defaults */
 462         cfg->stp = false;
 463         cfg->forward_delay = 2;
 464         cfg->igmp_snoop = true;
 465
 466         if ((cur = tb[BRIDGE_ATTR_STP]))
 467                 cfg->stp = blobmsg_get_bool(cur);
 468
 469         if ((cur = tb[BRIDGE_ATTR_FORWARD_DELAY]))
 470                 cfg->forward_delay = blobmsg_get_u32(cur);
 471
 472         if ((cur = tb[BRIDGE_ATTR_IGMP_SNOOP]))
 473                 cfg->igmp_snoop = blobmsg_get_bool(cur);
 474
 475         if ((cur = tb[BRIDGE_ATTR_AGEING_TIME])) {
 476                 cfg->ageing_time = blobmsg_get_u32(cur);
 477                 cfg->flags |= BRIDGE_OPT_AGEING_TIME;
 478         }
 479
 480         if ((cur = tb[BRIDGE_ATTR_HELLO_TIME])) {
 481                 cfg->hello_time = blobmsg_get_u32(cur);
 482                 cfg->flags |= BRIDGE_OPT_HELLO_TIME;
 483         }
 484
 485         if ((cur = tb[BRIDGE_ATTR_MAX_AGE])) {
 486                 cfg->max_age = blobmsg_get_u32(cur);
 487                 cfg->flags |= BRIDGE_OPT_MAX_AGE;
 488         }
 489 }
 490
 491 enum dev_change_type
 492 bridge_reload(struct device *dev, struct blob_attr *attr)
 493 {
 494         struct blob_attr *tb_dev[__DEV_ATTR_MAX];
 495         struct blob_attr *tb_br[__BRIDGE_ATTR_MAX];
 496         enum dev_change_type ret = DEV_CONFIG_APPLIED;
 497         unsigned long diff;
 498         struct bridge_state *bst;
 499
 500         BUILD_BUG_ON(sizeof(diff) < __BRIDGE_ATTR_MAX / 8);
 501         BUILD_BUG_ON(sizeof(diff) < __DEV_ATTR_MAX / 8);
 502
 503         bst = container_of(dev, struct bridge_state, dev);
 504
 505         blobmsg_parse(device_attr_list.params, __DEV_ATTR_MAX, tb_dev,
 506                 blob_data(attr), blob_len(attr));
 507         blobmsg_parse(bridge_attrs, __BRIDGE_ATTR_MAX, tb_br,
 508                 blob_data(attr), blob_len(attr));
 509
 510         bst->ifnames = tb_br[BRIDGE_ATTR_IFNAME];
 511         device_init_settings(dev, tb_dev);
 512         bridge_apply_settings(bst, tb_br);
 513
 514         if (bst->config_data) {
 515                 struct blob_attr *otb_dev[__DEV_ATTR_MAX];
 516                 struct blob_attr *otb_br[__BRIDGE_ATTR_MAX];
 517
 518                 blobmsg_parse(device_attr_list.params, __DEV_ATTR_MAX, otb_dev,
 519                         blob_data(bst->config_data), blob_len(bst->config_data));
 520
 521                 diff = 0;
 522                 config_diff(tb_dev, otb_dev, &device_attr_list, &diff);
 523                 if (diff & ~(1 << DEV_ATTR_IFNAME))
 524                     ret = DEV_CONFIG_RESTART;
 525
 526                 blobmsg_parse(bridge_attrs, __BRIDGE_ATTR_MAX, otb_br,
 527                         blob_data(bst->config_data), blob_len(bst->config_data));
 528
 529                 diff = 0;
 530                 config_diff(tb_br, otb_br, &bridge_attr_list, &diff);
 531                 if (diff & ~(1 << BRIDGE_ATTR_IFNAME))
 532                     ret = DEV_CONFIG_RESTART;
 533
 534                 bridge_config_init(dev);
 535         }
 536
 537         bst->config_data = attr;
 538         return ret;
 539 }
 540
 541 static struct device *
 542 bridge_create(const char *name, struct blob_attr *attr)
 543 {
 544         struct bridge_state *bst;
 545         struct device *dev = NULL;
 546
 547         bst = calloc(1, sizeof(*bst));
 548         if (!bst)
 549                 return NULL;
 550
 551         dev = &bst->dev;
 552         device_init(dev, &bridge_device_type, name);
 553         dev->config_pending = true;
 554
 555         bst->set_state = dev->set_state;
 556         dev->set_state = bridge_set_state;
 557
 558         dev->hotplug_ops = &bridge_ops;
 559
 560         vlist_init(&bst->members, avl_strcmp, bridge_member_update);
 561         bst->members.keep_old = true;
 562         bridge_reload(dev, attr);
 563
 564         return dev;
 565 }
 566
 567