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_PRIORITY,
  30         BRIDGE_ATTR_IGMP_SNOOP,
  31         BRIDGE_ATTR_AGEING_TIME,
  32         BRIDGE_ATTR_HELLO_TIME,
  33         BRIDGE_ATTR_MAX_AGE,
  34         BRIDGE_ATTR_BRIDGE_EMPTY,
  35         __BRIDGE_ATTR_MAX
  36 };
  37
  38 static const struct blobmsg_policy bridge_attrs[__BRIDGE_ATTR_MAX] = {
  39         [BRIDGE_ATTR_IFNAME] = { "ifname", BLOBMSG_TYPE_ARRAY },
  40         [BRIDGE_ATTR_STP] = { "stp", BLOBMSG_TYPE_BOOL },
  41         [BRIDGE_ATTR_FORWARD_DELAY] = { "forward_delay", BLOBMSG_TYPE_INT32 },
  42         [BRIDGE_ATTR_PRIORITY] = { "priority", BLOBMSG_TYPE_INT32 },
  43         [BRIDGE_ATTR_AGEING_TIME] = { "ageing_time", BLOBMSG_TYPE_INT32 },
  44         [BRIDGE_ATTR_HELLO_TIME] = { "hello_time", BLOBMSG_TYPE_INT32 },
  45         [BRIDGE_ATTR_MAX_AGE] = { "max_age", BLOBMSG_TYPE_INT32 },
  46         [BRIDGE_ATTR_IGMP_SNOOP] = { "igmp_snooping", BLOBMSG_TYPE_BOOL },
  47         [BRIDGE_ATTR_BRIDGE_EMPTY] = { "bridge_empty", BLOBMSG_TYPE_BOOL },
  48 };
  49
  50 static const struct uci_blob_param_info bridge_attr_info[__BRIDGE_ATTR_MAX] = {
  51         [BRIDGE_ATTR_IFNAME] = { .type = BLOBMSG_TYPE_STRING },
  52 };
  53
  54 static const struct uci_blob_param_list bridge_attr_list = {
  55         .n_params = __BRIDGE_ATTR_MAX,
  56         .params = bridge_attrs,
  57         .info = bridge_attr_info,
  58
  59         .n_next = 1,
  60         .next = { &device_attr_list },
  61 };
  62
  63 static struct device *bridge_create(const char *name, struct blob_attr *attr);
  64 static void bridge_config_init(struct device *dev);
  65 static void bridge_free(struct device *dev);
  66 static void bridge_dump_info(struct device *dev, struct blob_buf *b);
  67 enum dev_change_type
  68 bridge_reload(struct device *dev, struct blob_attr *attr);
  69
  70 const struct device_type bridge_device_type = {
  71         .name = "Bridge",
  72         .config_params = &bridge_attr_list,
  73
  74         .create = bridge_create,
  75         .config_init = bridge_config_init,
  76         .reload = bridge_reload,
  77         .free = bridge_free,
  78         .dump_info = bridge_dump_info,
  79 };
  80
  81 struct bridge_state {
  82         struct device dev;
  83         device_state_cb set_state;
  84
  85         struct blob_attr *config_data;
  86         struct bridge_config config;
  87         struct blob_attr *ifnames;
  88         bool active;
  89         bool force_active;
  90
  91         struct bridge_member *primary_port;
  92         struct vlist_tree members;
  93         int n_present;
  94 };
  95
  96 struct bridge_member {
  97         struct vlist_node node;
  98         struct bridge_state *bst;
  99         struct device_user dev;
 100         bool present;
 101         char name[];
 102 };
 103
 104 static void
 105 bridge_reset_primary(struct bridge_state *bst)
 106 {
 107         struct bridge_member *bm;
 108
 109         if (!bst->primary_port &&
 110             (bst->dev.settings.flags & DEV_OPT_MACADDR))
 111                 return;
 112
 113         bst->primary_port = NULL;
 114         bst->dev.settings.flags &= ~DEV_OPT_MACADDR;
 115         vlist_for_each_element(&bst->members, bm, node) {
 116                 uint8_t *macaddr;
 117
 118                 if (!bm->present)
 119                         continue;
 120
 121                 bst->primary_port = bm;
 122                 if (bm->dev.dev->settings.flags & DEV_OPT_MACADDR)
 123                         macaddr = bm->dev.dev->settings.macaddr;
 124                 else
 125                         macaddr = bm->dev.dev->orig_settings.macaddr;
 126                 memcpy(bst->dev.settings.macaddr, macaddr, 6);
 127                 bst->dev.settings.flags |= DEV_OPT_MACADDR;
 128                 return;
 129         }
 130 }
 131
 132 static int
 133 bridge_disable_member(struct bridge_member *bm)
 134 {
 135         struct bridge_state *bst = bm->bst;
 136
 137         if (!bm->present)
 138                 return 0;
 139
 140         system_bridge_delif(&bst->dev, bm->dev.dev);
 141         device_release(&bm->dev);
 142
 143         device_broadcast_event(&bst->dev, DEV_EVENT_TOPO_CHANGE);
 144
 145         return 0;
 146 }
 147
 148 static int
 149 bridge_enable_member(struct bridge_member *bm)
 150 {
 151         struct bridge_state *bst = bm->bst;
 152         int ret;
 153
 154         if (!bm->present)
 155                 return 0;
 156
 157         ret = device_claim(&bm->dev);
 158         if (ret < 0)
 159                 goto error;
 160
 161         ret = system_bridge_addif(&bst->dev, bm->dev.dev);
 162         if (ret < 0) {
 163                 D(DEVICE, "Bridge device %s could not be added\n", bm->dev.dev->ifname);
 164                 goto error;
 165         }
 166
 167         device_broadcast_event(&bst->dev, DEV_EVENT_TOPO_CHANGE);
 168
 169         return 0;
 170
 171 error:
 172         bm->present = false;
 173         bst->n_present--;
 174         return ret;
 175 }
 176
 177 static void
 178 bridge_remove_member(struct bridge_member *bm)
 179 {
 180         struct bridge_state *bst = bm->bst;
 181
 182         if (!bm->present)
 183                 return;
 184
 185         if (bm == bst->primary_port)
 186                 bridge_reset_primary(bst);
 187
 188         if (bst->dev.active)
 189                 bridge_disable_member(bm);
 190
 191         bm->present = false;
 192         bm->bst->n_present--;
 193
 194         if (bst->config.bridge_empty)
 195                 return;
 196
 197         bst->force_active = false;
 198         if (bst->n_present == 0)
 199                 device_set_present(&bst->dev, false);
 200 }
 201
 202 static void
 203 bridge_free_member(struct bridge_member *bm)
 204 {
 205         struct device *dev = bm->dev.dev;
 206
 207         bridge_remove_member(bm);
 208         device_remove_user(&bm->dev);
 209
 210         /*
 211          * When reloading the config and moving a device from one bridge to
 212          * another, the other bridge may have tried to claim this device
 213          * before it was removed here.
 214          * Ensure that claiming the device is retried by toggling its present
 215          * state
 216          */
 217         if (dev->present) {
 218                 device_set_present(dev, false);
 219                 device_set_present(dev, true);
 220         }
 221
 222         free(bm);
 223 }
 224
 225 static void
 226 bridge_member_cb(struct device_user *dev, enum device_event ev)
 227 {
 228         struct bridge_member *bm = container_of(dev, struct bridge_member, dev);
 229         struct bridge_state *bst = bm->bst;
 230
 231         switch (ev) {
 232         case DEV_EVENT_ADD:
 233                 assert(!bm->present);
 234
 235                 bm->present = true;
 236                 bst->n_present++;
 237
 238                 if (bst->n_present == 1)
 239                         device_set_present(&bst->dev, true);
 240                 if (bst->dev.active && !bridge_enable_member(bm)) {
 241                         /*
 242                          * Adding a bridge member can overwrite the bridge mtu
 243                          * in the kernel, apply the bridge settings in case the
 244                          * bridge mtu is set
 245                          */
 246                         system_if_apply_settings(&bst->dev, &bst->dev.settings,
 247                                                  DEV_OPT_MTU);
 248                 }
 249
 250                 break;
 251         case DEV_EVENT_REMOVE:
 252                 if (dev->hotplug) {
 253                         vlist_delete(&bst->members, &bm->node);
 254                         return;
 255                 }
 256
 257                 if (bm->present)
 258                         bridge_remove_member(bm);
 259
 260                 break;
 261         default:
 262                 return;
 263         }
 264 }
 265
 266 static int
 267 bridge_set_down(struct bridge_state *bst)
 268 {
 269         struct bridge_member *bm;
 270
 271         bst->set_state(&bst->dev, false);
 272
 273         vlist_for_each_element(&bst->members, bm, node)
 274                 bridge_disable_member(bm);
 275
 276         system_bridge_delbr(&bst->dev);
 277
 278         return 0;
 279 }
 280
 281 static int
 282 bridge_set_up(struct bridge_state *bst)
 283 {
 284         struct bridge_member *bm;
 285         int ret;
 286
 287         if (!bst->force_active && !bst->n_present)
 288                 return -ENOENT;
 289
 290         ret = system_bridge_addbr(&bst->dev, &bst->config);
 291         if (ret < 0)
 292                 goto out;
 293
 294         vlist_for_each_element(&bst->members, bm, node)
 295                 bridge_enable_member(bm);
 296
 297         if (!bst->force_active && !bst->n_present) {
 298                 /* initialization of all member interfaces failed */
 299                 system_bridge_delbr(&bst->dev);
 300                 device_set_present(&bst->dev, false);
 301                 return -ENOENT;
 302         }
 303
 304         bridge_reset_primary(bst);
 305         ret = bst->set_state(&bst->dev, true);
 306         if (ret < 0)
 307                 bridge_set_down(bst);
 308
 309 out:
 310         return ret;
 311 }
 312
 313 static int
 314 bridge_set_state(struct device *dev, bool up)
 315 {
 316         struct bridge_state *bst;
 317
 318         bst = container_of(dev, struct bridge_state, dev);
 319
 320         if (up)
 321                 return bridge_set_up(bst);
 322         else
 323                 return bridge_set_down(bst);
 324 }
 325
 326 static struct bridge_member *
 327 bridge_create_member(struct bridge_state *bst, struct device *dev, bool hotplug)
 328 {
 329         struct bridge_member *bm;
 330
 331         bm = calloc(1, sizeof(*bm) + strlen(dev->ifname) + 1);
 332         if (!bm)
 333                 return NULL;
 334
 335         bm->bst = bst;
 336         bm->dev.cb = bridge_member_cb;
 337         bm->dev.hotplug = hotplug;
 338         strcpy(bm->name, dev->ifname);
 339         bm->dev.dev = dev;
 340         vlist_add(&bst->members, &bm->node, bm->name);
 341         if (hotplug)
 342                 bm->node.version = -1;
 343
 344         return bm;
 345 }
 346
 347 static void
 348 bridge_member_update(struct vlist_tree *tree, struct vlist_node *node_new,
 349                      struct vlist_node *node_old)
 350 {
 351         struct bridge_member *bm;
 352         struct device *dev;
 353
 354         if (node_new) {
 355                 bm = container_of(node_new, struct bridge_member, node);
 356
 357                 if (node_old) {
 358                         free(bm);
 359                         return;
 360                 }
 361
 362                 dev = bm->dev.dev;
 363                 bm->dev.dev = NULL;
 364                 device_add_user(&bm->dev, dev);
 365         }
 366
 367
 368         if (node_old) {
 369                 bm = container_of(node_old, struct bridge_member, node);
 370                 bridge_free_member(bm);
 371         }
 372 }
 373
 374
 375 static void
 376 bridge_add_member(struct bridge_state *bst, const char *name)
 377 {
 378         struct device *dev;
 379
 380         dev = device_get(name, true);
 381         if (!dev)
 382                 return;
 383
 384         bridge_create_member(bst, dev, false);
 385 }
 386
 387 static int
 388 bridge_hotplug_add(struct device *dev, struct device *member)
 389 {
 390         struct bridge_state *bst = container_of(dev, struct bridge_state, dev);
 391
 392         bridge_create_member(bst, member, true);
 393
 394         return 0;
 395 }
 396
 397 static int
 398 bridge_hotplug_del(struct device *dev, struct device *member)
 399 {
 400         struct bridge_state *bst = container_of(dev, struct bridge_state, dev);
 401         struct bridge_member *bm;
 402
 403         bm = vlist_find(&bst->members, member->ifname, bm, node);
 404         if (!bm)
 405                 return UBUS_STATUS_NOT_FOUND;
 406
 407         vlist_delete(&bst->members, &bm->node);
 408         return 0;
 409 }
 410
 411 static int
 412 bridge_hotplug_prepare(struct device *dev)
 413 {
 414         struct bridge_state *bst;
 415
 416         bst = container_of(dev, struct bridge_state, dev);
 417         bst->force_active = true;
 418         device_set_present(&bst->dev, true);
 419
 420         return 0;
 421 }
 422
 423 static const struct device_hotplug_ops bridge_ops = {
 424         .prepare = bridge_hotplug_prepare,
 425         .add = bridge_hotplug_add,
 426         .del = bridge_hotplug_del
 427 };
 428
 429 static void
 430 bridge_free(struct device *dev)
 431 {
 432         struct bridge_state *bst;
 433
 434         bst = container_of(dev, struct bridge_state, dev);
 435         vlist_flush_all(&bst->members);
 436         free(bst);
 437 }
 438
 439 static void
 440 bridge_dump_info(struct device *dev, struct blob_buf *b)
 441 {
 442         struct bridge_state *bst;
 443         struct bridge_member *bm;
 444         void *list;
 445
 446         bst = container_of(dev, struct bridge_state, dev);
 447
 448         system_if_dump_info(dev, b);
 449         list = blobmsg_open_array(b, "bridge-members");
 450
 451         vlist_for_each_element(&bst->members, bm, node)
 452                 blobmsg_add_string(b, NULL, bm->dev.dev->ifname);
 453
 454         blobmsg_close_array(b, list);
 455 }
 456
 457 static void
 458 bridge_config_init(struct device *dev)
 459 {
 460         struct bridge_state *bst;
 461         struct blob_attr *cur;
 462         int rem;
 463
 464         bst = container_of(dev, struct bridge_state, dev);
 465
 466         if (bst->config.bridge_empty) {
 467                 bst->force_active = true;
 468                 device_set_present(&bst->dev, true);
 469         }
 470
 471         vlist_update(&bst->members);
 472         if (bst->ifnames) {
 473                 blobmsg_for_each_attr(cur, bst->ifnames, rem) {
 474                         bridge_add_member(bst, blobmsg_data(cur));
 475                 }
 476         }
 477         vlist_flush(&bst->members);
 478 }
 479
 480 static void
 481 bridge_apply_settings(struct bridge_state *bst, struct blob_attr **tb)
 482 {
 483         struct bridge_config *cfg = &bst->config;
 484         struct blob_attr *cur;
 485
 486         /* defaults */
 487         cfg->stp = false;
 488         cfg->forward_delay = 2;
 489         cfg->igmp_snoop = false;
 490         cfg->bridge_empty = false;
 491         cfg->priority = 0x7FFF;
 492
 493         if ((cur = tb[BRIDGE_ATTR_STP]))
 494                 cfg->stp = blobmsg_get_bool(cur);
 495
 496         if ((cur = tb[BRIDGE_ATTR_FORWARD_DELAY]))
 497                 cfg->forward_delay = blobmsg_get_u32(cur);
 498
 499         if ((cur = tb[BRIDGE_ATTR_PRIORITY]))
 500                 cfg->priority = blobmsg_get_u32(cur);
 501
 502         if ((cur = tb[BRIDGE_ATTR_IGMP_SNOOP]))
 503                 cfg->igmp_snoop = blobmsg_get_bool(cur);
 504
 505         if ((cur = tb[BRIDGE_ATTR_AGEING_TIME])) {
 506                 cfg->ageing_time = blobmsg_get_u32(cur);
 507                 cfg->flags |= BRIDGE_OPT_AGEING_TIME;
 508         }
 509
 510         if ((cur = tb[BRIDGE_ATTR_HELLO_TIME])) {
 511                 cfg->hello_time = blobmsg_get_u32(cur);
 512                 cfg->flags |= BRIDGE_OPT_HELLO_TIME;
 513         }
 514
 515         if ((cur = tb[BRIDGE_ATTR_MAX_AGE])) {
 516                 cfg->max_age = blobmsg_get_u32(cur);
 517                 cfg->flags |= BRIDGE_OPT_MAX_AGE;
 518         }
 519
 520         if ((cur = tb[BRIDGE_ATTR_BRIDGE_EMPTY]))
 521                 cfg->bridge_empty = blobmsg_get_bool(cur);
 522 }
 523
 524 enum dev_change_type
 525 bridge_reload(struct device *dev, struct blob_attr *attr)
 526 {
 527         struct blob_attr *tb_dev[__DEV_ATTR_MAX];
 528         struct blob_attr *tb_br[__BRIDGE_ATTR_MAX];
 529         enum dev_change_type ret = DEV_CONFIG_APPLIED;
 530         unsigned long diff;
 531         struct bridge_state *bst;
 532
 533         BUILD_BUG_ON(sizeof(diff) < __BRIDGE_ATTR_MAX / 8);
 534         BUILD_BUG_ON(sizeof(diff) < __DEV_ATTR_MAX / 8);
 535
 536         bst = container_of(dev, struct bridge_state, dev);
 537
 538         blobmsg_parse(device_attr_list.params, __DEV_ATTR_MAX, tb_dev,
 539                 blob_data(attr), blob_len(attr));
 540         blobmsg_parse(bridge_attrs, __BRIDGE_ATTR_MAX, tb_br,
 541                 blob_data(attr), blob_len(attr));
 542
 543         bst->ifnames = tb_br[BRIDGE_ATTR_IFNAME];
 544         device_init_settings(dev, tb_dev);
 545         bridge_apply_settings(bst, tb_br);
 546
 547         if (bst->config_data) {
 548                 struct blob_attr *otb_dev[__DEV_ATTR_MAX];
 549                 struct blob_attr *otb_br[__BRIDGE_ATTR_MAX];
 550
 551                 blobmsg_parse(device_attr_list.params, __DEV_ATTR_MAX, otb_dev,
 552                         blob_data(bst->config_data), blob_len(bst->config_data));
 553
 554                 diff = 0;
 555                 uci_blob_diff(tb_dev, otb_dev, &device_attr_list, &diff);
 556                 if (diff & ~(1 << DEV_ATTR_IFNAME))
 557                     ret = DEV_CONFIG_RESTART;
 558
 559                 blobmsg_parse(bridge_attrs, __BRIDGE_ATTR_MAX, otb_br,
 560                         blob_data(bst->config_data), blob_len(bst->config_data));
 561
 562                 diff = 0;
 563                 uci_blob_diff(tb_br, otb_br, &bridge_attr_list, &diff);
 564                 if (diff & ~(1 << BRIDGE_ATTR_IFNAME))
 565                     ret = DEV_CONFIG_RESTART;
 566
 567                 bridge_config_init(dev);
 568         }
 569
 570         bst->config_data = attr;
 571         return ret;
 572 }
 573
 574 static struct device *
 575 bridge_create(const char *name, struct blob_attr *attr)
 576 {
 577         struct bridge_state *bst;
 578         struct device *dev = NULL;
 579
 580         bst = calloc(1, sizeof(*bst));
 581         if (!bst)
 582                 return NULL;
 583
 584         dev = &bst->dev;
 585         device_init(dev, &bridge_device_type, name);
 586         dev->config_pending = true;
 587
 588         bst->set_state = dev->set_state;
 589         dev->set_state = bridge_set_state;
 590
 591         dev->hotplug_ops = &bridge_ops;
 592
 593         vlist_init(&bst->members, avl_strcmp, bridge_member_update);
 594         bst->members.keep_old = true;
 595         bridge_reload(dev, attr);
 596
 597         return dev;
 598 }