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