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->dev.active)
 235                         bridge_enable_member(bm);
 236                 else if (bst->n_present == 1)
 237                         device_set_present(&bst->dev, true);
 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         bm->bst = bst;
 322         bm->dev.cb = bridge_member_cb;
 323         bm->dev.hotplug = hotplug;
 324         strcpy(bm->name, dev->ifname);
 325         bm->dev.dev = dev;
 326         vlist_add(&bst->members, &bm->node, bm->name);
 327         if (hotplug)
 328                 bm->node.version = -1;
 329
 330         return bm;
 331 }
 332
 333 static void
 334 bridge_member_update(struct vlist_tree *tree, struct vlist_node *node_new,
 335                      struct vlist_node *node_old)
 336 {
 337         struct bridge_member *bm;
 338         struct device *dev;
 339
 340         if (node_new) {
 341                 bm = container_of(node_new, struct bridge_member, node);
 342
 343                 if (node_old) {
 344                         free(bm);
 345                         return;
 346                 }
 347
 348                 dev = bm->dev.dev;
 349                 bm->dev.dev = NULL;
 350                 device_add_user(&bm->dev, dev);
 351         }
 352
 353
 354         if (node_old) {
 355                 bm = container_of(node_old, struct bridge_member, node);
 356                 bridge_free_member(bm);
 357         }
 358 }
 359
 360
 361 static void
 362 bridge_add_member(struct bridge_state *bst, const char *name)
 363 {
 364         struct device *dev;
 365
 366         dev = device_get(name, true);
 367         if (!dev)
 368                 return;
 369
 370         bridge_create_member(bst, dev, false);
 371 }
 372
 373 static int
 374 bridge_hotplug_add(struct device *dev, struct device *member)
 375 {
 376         struct bridge_state *bst = container_of(dev, struct bridge_state, dev);
 377
 378         bridge_create_member(bst, member, true);
 379
 380         return 0;
 381 }
 382
 383 static int
 384 bridge_hotplug_del(struct device *dev, struct device *member)
 385 {
 386         struct bridge_state *bst = container_of(dev, struct bridge_state, dev);
 387         struct bridge_member *bm;
 388
 389         bm = vlist_find(&bst->members, member->ifname, bm, node);
 390         if (!bm)
 391                 return UBUS_STATUS_NOT_FOUND;
 392
 393         vlist_delete(&bst->members, &bm->node);
 394         return 0;
 395 }
 396
 397 static int
 398 bridge_hotplug_prepare(struct device *dev)
 399 {
 400         struct bridge_state *bst;
 401
 402         bst = container_of(dev, struct bridge_state, dev);
 403         bst->force_active = true;
 404         device_set_present(&bst->dev, true);
 405
 406         return 0;
 407 }
 408
 409 static const struct device_hotplug_ops bridge_ops = {
 410         .prepare = bridge_hotplug_prepare,
 411         .add = bridge_hotplug_add,
 412         .del = bridge_hotplug_del
 413 };
 414
 415 static void
 416 bridge_free(struct device *dev)
 417 {
 418         struct bridge_state *bst;
 419
 420         bst = container_of(dev, struct bridge_state, dev);
 421         vlist_flush_all(&bst->members);
 422         free(bst);
 423 }
 424
 425 static void
 426 bridge_dump_info(struct device *dev, struct blob_buf *b)
 427 {
 428         struct bridge_state *bst;
 429         struct bridge_member *bm;
 430         void *list;
 431
 432         bst = container_of(dev, struct bridge_state, dev);
 433
 434         system_if_dump_info(dev, b);
 435         list = blobmsg_open_array(b, "bridge-members");
 436
 437         vlist_for_each_element(&bst->members, bm, node)
 438                 blobmsg_add_string(b, NULL, bm->dev.dev->ifname);
 439
 440         blobmsg_close_array(b, list);
 441 }
 442
 443 static void
 444 bridge_config_init(struct device *dev)
 445 {
 446         struct bridge_state *bst;
 447         struct blob_attr *cur;
 448         int rem;
 449
 450         bst = container_of(dev, struct bridge_state, dev);
 451
 452         if (bst->config.bridge_empty) {
 453                 bst->force_active = true;
 454                 device_set_present(&bst->dev, true);
 455         }
 456
 457         vlist_update(&bst->members);
 458         if (bst->ifnames) {
 459                 blobmsg_for_each_attr(cur, bst->ifnames, rem) {
 460                         bridge_add_member(bst, blobmsg_data(cur));
 461                 }
 462         }
 463         vlist_flush(&bst->members);
 464 }
 465
 466 static void
 467 bridge_apply_settings(struct bridge_state *bst, struct blob_attr **tb)
 468 {
 469         struct bridge_config *cfg = &bst->config;
 470         struct blob_attr *cur;
 471
 472         /* defaults */
 473         cfg->stp = false;
 474         cfg->forward_delay = 2;
 475         cfg->igmp_snoop = false;
 476         cfg->bridge_empty = false;
 477         cfg->priority = 0x7FFF;
 478
 479         if ((cur = tb[BRIDGE_ATTR_STP]))
 480                 cfg->stp = blobmsg_get_bool(cur);
 481
 482         if ((cur = tb[BRIDGE_ATTR_FORWARD_DELAY]))
 483                 cfg->forward_delay = blobmsg_get_u32(cur);
 484
 485         if ((cur = tb[BRIDGE_ATTR_PRIORITY]))
 486                 cfg->priority = blobmsg_get_u32(cur);
 487
 488         if ((cur = tb[BRIDGE_ATTR_IGMP_SNOOP]))
 489                 cfg->igmp_snoop = blobmsg_get_bool(cur);
 490
 491         if ((cur = tb[BRIDGE_ATTR_AGEING_TIME])) {
 492                 cfg->ageing_time = blobmsg_get_u32(cur);
 493                 cfg->flags |= BRIDGE_OPT_AGEING_TIME;
 494         }
 495
 496         if ((cur = tb[BRIDGE_ATTR_HELLO_TIME])) {
 497                 cfg->hello_time = blobmsg_get_u32(cur);
 498                 cfg->flags |= BRIDGE_OPT_HELLO_TIME;
 499         }
 500
 501         if ((cur = tb[BRIDGE_ATTR_MAX_AGE])) {
 502                 cfg->max_age = blobmsg_get_u32(cur);
 503                 cfg->flags |= BRIDGE_OPT_MAX_AGE;
 504         }
 505
 506         if ((cur = tb[BRIDGE_ATTR_BRIDGE_EMPTY]))
 507                 cfg->bridge_empty = blobmsg_get_bool(cur);
 508 }
 509
 510 enum dev_change_type
 511 bridge_reload(struct device *dev, struct blob_attr *attr)
 512 {
 513         struct blob_attr *tb_dev[__DEV_ATTR_MAX];
 514         struct blob_attr *tb_br[__BRIDGE_ATTR_MAX];
 515         enum dev_change_type ret = DEV_CONFIG_APPLIED;
 516         unsigned long diff;
 517         struct bridge_state *bst;
 518
 519         BUILD_BUG_ON(sizeof(diff) < __BRIDGE_ATTR_MAX / 8);
 520         BUILD_BUG_ON(sizeof(diff) < __DEV_ATTR_MAX / 8);
 521
 522         bst = container_of(dev, struct bridge_state, dev);
 523
 524         blobmsg_parse(device_attr_list.params, __DEV_ATTR_MAX, tb_dev,
 525                 blob_data(attr), blob_len(attr));
 526         blobmsg_parse(bridge_attrs, __BRIDGE_ATTR_MAX, tb_br,
 527                 blob_data(attr), blob_len(attr));
 528
 529         bst->ifnames = tb_br[BRIDGE_ATTR_IFNAME];
 530         device_init_settings(dev, tb_dev);
 531         bridge_apply_settings(bst, tb_br);
 532
 533         if (bst->config_data) {
 534                 struct blob_attr *otb_dev[__DEV_ATTR_MAX];
 535                 struct blob_attr *otb_br[__BRIDGE_ATTR_MAX];
 536
 537                 blobmsg_parse(device_attr_list.params, __DEV_ATTR_MAX, otb_dev,
 538                         blob_data(bst->config_data), blob_len(bst->config_data));
 539
 540                 diff = 0;
 541                 uci_blob_diff(tb_dev, otb_dev, &device_attr_list, &diff);
 542                 if (diff & ~(1 << DEV_ATTR_IFNAME))
 543                     ret = DEV_CONFIG_RESTART;
 544
 545                 blobmsg_parse(bridge_attrs, __BRIDGE_ATTR_MAX, otb_br,
 546                         blob_data(bst->config_data), blob_len(bst->config_data));
 547
 548                 diff = 0;
 549                 uci_blob_diff(tb_br, otb_br, &bridge_attr_list, &diff);
 550                 if (diff & ~(1 << BRIDGE_ATTR_IFNAME))
 551                     ret = DEV_CONFIG_RESTART;
 552
 553                 bridge_config_init(dev);
 554         }
 555
 556         bst->config_data = attr;
 557         return ret;
 558 }
 559
 560 static struct device *
 561 bridge_create(const char *name, struct blob_attr *attr)
 562 {
 563         struct bridge_state *bst;
 564         struct device *dev = NULL;
 565
 566         bst = calloc(1, sizeof(*bst));
 567         if (!bst)
 568                 return NULL;
 569
 570         dev = &bst->dev;
 571         device_init(dev, &bridge_device_type, name);
 572         dev->config_pending = true;
 573
 574         bst->set_state = dev->set_state;
 575         dev->set_state = bridge_set_state;
 576
 577         dev->hotplug_ops = &bridge_ops;
 578
 579         vlist_init(&bst->members, avl_strcmp, bridge_member_update);
 580         bst->members.keep_old = true;
 581         bridge_reload(dev, attr);
 582
 583         return dev;
 584 }