device.c

   1 #include <string.h>
   2 #include <stdlib.h>
   3 #include <stdio.h>
   4 #include <assert.h>
   5
   6 #include <sys/types.h>
   7 #include <sys/socket.h>
   8 #include <net/ethernet.h>
   9
  10 #ifdef linux
  11 #include <netinet/ether.h>
  12 #endif
  13
  14 #include "netifd.h"
  15 #include "system.h"
  16 #include "config.h"
  17
  18 static struct avl_tree devices;
  19
  20 static const struct blobmsg_policy dev_attrs[__DEV_ATTR_MAX] = {
  21         [DEV_ATTR_TYPE] = { "type", BLOBMSG_TYPE_STRING },
  22         [DEV_ATTR_NAME] = { "name", BLOBMSG_TYPE_STRING },
  23         [DEV_ATTR_IFNAME] = { "ifname", BLOBMSG_TYPE_ARRAY },
  24         [DEV_ATTR_MTU] = { "mtu", BLOBMSG_TYPE_INT32 },
  25         [DEV_ATTR_MACADDR] = { "macaddr", BLOBMSG_TYPE_STRING },
  26         [DEV_ATTR_TXQUEUELEN] = { "txqueuelen", BLOBMSG_TYPE_INT32 },
  27 };
  28
  29 const struct config_param_list device_attr_list = {
  30         .n_params = __DEV_ATTR_MAX,
  31         .params = dev_attrs,
  32 };
  33
  34 static struct device *
  35 simple_device_create(struct blob_attr *attr)
  36 {
  37         struct blob_attr *tb[__DEV_ATTR_MAX];
  38         struct device *dev = NULL;
  39         const char *name;
  40
  41         blobmsg_parse(dev_attrs, __DEV_ATTR_MAX, tb, blob_data(attr), blob_len(attr));
  42         if (!tb[DEV_ATTR_NAME])
  43                 return NULL;
  44
  45         name = blobmsg_data(tb[DEV_ATTR_NAME]);
  46         if (!name)
  47                 return NULL;
  48
  49         dev = device_get(name, true);
  50         if (!dev)
  51                 return NULL;
  52
  53         device_init_settings(dev, tb);
  54
  55         return dev;
  56 }
  57
  58 static void simple_device_free(struct device *dev)
  59 {
  60         device_cleanup(dev);
  61         free(dev);
  62 }
  63
  64 const struct device_type simple_device_type = {
  65         .name = "Network device",
  66         .config_params = &device_attr_list,
  67
  68         .create = simple_device_create,
  69         .check_state = system_if_check,
  70         .free = simple_device_free,
  71 };
  72
  73 void
  74 device_init_settings(struct device *dev, struct blob_attr **tb)
  75 {
  76         struct blob_attr *cur;
  77         struct ether_addr *ea;
  78
  79         dev->flags = 0;
  80
  81         if ((cur = tb[DEV_ATTR_MTU])) {
  82                 dev->mtu = blobmsg_get_u32(cur);
  83                 dev->flags |= DEV_OPT_MTU;
  84         }
  85
  86         if ((cur = tb[DEV_ATTR_TXQUEUELEN])) {
  87                 dev->txqueuelen = blobmsg_get_u32(cur);
  88                 dev->flags |= DEV_OPT_TXQUEUELEN;
  89         }
  90
  91         if ((cur = tb[DEV_ATTR_MACADDR])) {
  92                 ea = ether_aton(blob_data(cur));
  93                 if (ea) {
  94                         memcpy(dev->macaddr, ea, sizeof(dev->macaddr));
  95                         dev->flags |= DEV_OPT_MACADDR;
  96                 }
  97         }
  98 }
  99
 100 static void __init dev_init(void)
 101 {
 102         avl_init(&devices, avl_strcmp, true, NULL);
 103 }
 104
 105 static void device_broadcast_event(struct device *dev, enum device_event ev)
 106 {
 107         struct device_user *dep, *tmp;
 108
 109         list_for_each_entry_safe(dep, tmp, &dev->users, list) {
 110                 if (!dep->cb)
 111                         continue;
 112
 113                 dep->cb(dep, ev);
 114         }
 115 }
 116
 117 static int set_device_state(struct device *dev, bool state)
 118 {
 119         if (state)
 120                 system_if_up(dev);
 121         else
 122                 system_if_down(dev);
 123
 124         return 0;
 125 }
 126
 127 int device_claim(struct device_user *dep)
 128 {
 129         struct device *dev = dep->dev;
 130         int ret;
 131
 132         if (dep->claimed)
 133                 return 0;
 134
 135         dep->claimed = true;
 136         D(DEVICE, "claim device %s, new refcount: %d\n", dev->ifname, dev->active + 1);
 137         if (++dev->active != 1)
 138                 return 0;
 139
 140         device_broadcast_event(dev, DEV_EVENT_SETUP);
 141         ret = dev->set_state(dev, true);
 142         if (ret == 0)
 143                 device_broadcast_event(dev, DEV_EVENT_UP);
 144         else
 145                 dev->active = 0;
 146
 147         return ret;
 148 }
 149
 150 void device_release(struct device_user *dep)
 151 {
 152         struct device *dev = dep->dev;
 153
 154         if (!dep->claimed)
 155                 return;
 156
 157         dep->claimed = false;
 158         dev->active--;
 159         D(DEVICE, "release device %s, new refcount: %d\n", dev->ifname, dev->active);
 160         assert(dev->active >= 0);
 161
 162         if (dev->active)
 163                 return;
 164
 165         device_broadcast_event(dev, DEV_EVENT_TEARDOWN);
 166         dev->set_state(dev, false);
 167         device_broadcast_event(dev, DEV_EVENT_DOWN);
 168 }
 169
 170 int device_check_state(struct device *dev)
 171 {
 172         if (!dev->type->check_state)
 173                 return 0;
 174
 175         return dev->type->check_state(dev);
 176 }
 177
 178 void device_init_virtual(struct device *dev, const struct device_type *type, const char *name)
 179 {
 180         assert(dev);
 181         assert(type);
 182
 183         if (name)
 184                 strncpy(dev->ifname, name, IFNAMSIZ);
 185
 186         D(DEVICE, "Initialize device '%s'\n", dev->ifname);
 187         INIT_LIST_HEAD(&dev->users);
 188         dev->type = type;
 189 }
 190
 191 int device_init(struct device *dev, const struct device_type *type, const char *ifname)
 192 {
 193         int ret;
 194
 195         device_init_virtual(dev, type, ifname);
 196
 197         if (!dev->set_state)
 198                 dev->set_state = set_device_state;
 199
 200         dev->avl.key = dev->ifname;
 201
 202         ret = avl_insert(&devices, &dev->avl);
 203         if (ret < 0)
 204                 return ret;
 205
 206         device_check_state(dev);
 207
 208         return 0;
 209 }
 210
 211 struct device *device_get(const char *name, bool create)
 212 {
 213         struct device *dev;
 214
 215         if (strchr(name, '.'))
 216                 return get_vlan_device_chain(name, create);
 217
 218         dev = avl_find_element(&devices, name, dev, avl);
 219         if (dev)
 220                 return dev;
 221
 222         if (!create)
 223                 return NULL;
 224
 225         dev = calloc(1, sizeof(*dev));
 226         device_init(dev, &simple_device_type, name);
 227
 228         return dev;
 229 }
 230
 231 static void
 232 device_delete(struct device *dev)
 233 {
 234         if (!dev->avl.key)
 235                 return;
 236
 237         avl_delete(&devices, &dev->avl);
 238         dev->avl.key = NULL;
 239 }
 240
 241 void device_cleanup(struct device *dev)
 242 {
 243         struct device_user *dep, *tmp;
 244
 245         D(DEVICE, "Clean up device '%s'\n", dev->ifname);
 246         list_for_each_entry_safe(dep, tmp, &dev->users, list) {
 247                 if (!dep->cb)
 248                         continue;
 249
 250                 dep->cb(dep, DEV_EVENT_REMOVE);
 251         }
 252
 253         device_delete(dev);
 254 }
 255
 256 void device_set_present(struct device *dev, bool state)
 257 {
 258         if (dev->present == state)
 259                 return;
 260
 261         D(DEVICE, "Device '%s' %s present\n", dev->ifname, state ? "is now" : "is no longer" );
 262         dev->present = state;
 263         device_broadcast_event(dev, state ? DEV_EVENT_ADD : DEV_EVENT_REMOVE);
 264 }
 265
 266 void device_add_user(struct device_user *dep, struct device *dev)
 267 {
 268         dep->dev = dev;
 269         list_add_tail(&dep->list, &dev->users);
 270         if (dep->cb && dev->present) {
 271                 dep->cb(dep, DEV_EVENT_ADD);
 272                 if (dev->active)
 273                         dep->cb(dep, DEV_EVENT_UP);
 274         }
 275 }
 276
 277 static void
 278 __device_free_unused(struct device *dev)
 279 {
 280         if (!list_empty(&dev->users))
 281                 return;
 282
 283         device_free(dev);
 284 }
 285
 286 void device_remove_user(struct device_user *dep)
 287 {
 288         struct device *dev = dep->dev;
 289
 290         if (dep->claimed)
 291                 device_release(dep);
 292
 293         list_del(&dep->list);
 294         dep->dev = NULL;
 295         __device_free_unused(dev);
 296 }
 297
 298 void
 299 device_free_unused(struct device *dev)
 300 {
 301         struct device *tmp;
 302
 303         if (dev)
 304                 return __device_free_unused(dev);
 305
 306         avl_for_each_element_safe(&devices, dev, avl, tmp)
 307                 __device_free_unused(dev);
 308 }
 309
 310 void
 311 device_init_pending(void)
 312 {
 313         struct device *dev, *tmp;
 314
 315         avl_for_each_element_safe(&devices, dev, avl, tmp) {
 316                 if (!dev->config_pending)
 317                         continue;
 318
 319                 dev->type->config_init(dev);
 320                 dev->config_pending = false;
 321         }
 322 }
 323
 324 enum dev_change_type
 325 device_reload_config(struct device *dev, struct blob_attr *attr)
 326 {
 327         struct blob_attr *tb[__DEV_ATTR_MAX], *tb1[__DEV_ATTR_MAX];
 328
 329         blobmsg_parse(dev_attrs, __DEV_ATTR_MAX, tb,
 330                 blob_data(attr), blob_len(attr));
 331         if (dev->config)
 332                 blobmsg_parse(dev_attrs, __DEV_ATTR_MAX, tb1,
 333                         blob_data(dev->config), blob_len(dev->config));
 334         else
 335                 memset(tb1, 0, sizeof(tb1));
 336
 337         if (!config_diff(tb, tb1, &device_attr_list, NULL))
 338                 return DEV_CONFIG_NO_CHANGE;
 339
 340         device_init_settings(dev, tb);
 341         return DEV_CONFIG_APPLIED;
 342 }
 343
 344 static enum dev_change_type
 345 device_check_config(struct device *dev, struct blob_attr *attr)
 346 {
 347         if (dev->type->reload)
 348                 return dev->type->reload(dev, attr);
 349
 350         return device_reload_config(dev, attr);
 351 }
 352
 353 static void
 354 device_replace(struct device *dev, struct device *odev)
 355 {
 356         struct device_user *dep, *tmp;
 357         bool present = odev->present;
 358
 359         if (present)
 360                 device_set_present(odev, false);
 361
 362         list_for_each_entry_safe(dep, tmp, &odev->users, list) {
 363                 device_remove_user(dep);
 364                 device_add_user(dep, dev);
 365         }
 366         device_free(odev);
 367
 368         if (present)
 369                 device_set_present(dev, true);
 370 }
 371
 372 struct device *
 373 device_create(const char *name, const struct device_type *type,
 374               struct blob_attr *config)
 375 {
 376         struct device *odev = NULL, *dev;
 377         enum dev_change_type change;
 378
 379         D(DEVICE, "Create new device '%s' (%s)\n", name, type->name);
 380         config = config_memdup(config);
 381         if (!config)
 382                 return NULL;
 383
 384         odev = device_get(name, false);
 385         if (odev) {
 386                 change = device_check_config(odev, config);
 387                 switch (change) {
 388                 case DEV_CONFIG_APPLIED:
 389                         D(DEVICE, "Device '%s': config applied\n", odev->ifname);
 390                         free(odev->config);
 391                         odev->config = config;
 392                         if (odev->present) {
 393                                 device_set_present(odev, false);
 394                                 device_set_present(odev, true);
 395                         }
 396                         free(config);
 397                         return odev;
 398                 case DEV_CONFIG_NO_CHANGE:
 399                         D(DEVICE, "Device '%s': no configuration change\n", odev->ifname);
 400                         free(config);
 401                         return odev;
 402                 case DEV_CONFIG_RECREATE:
 403                         D(DEVICE, "Device '%s': recreate device\n", odev->ifname);
 404                         device_delete(odev);
 405                         break;
 406                 }
 407         }
 408
 409         dev = type->create(config);
 410         if (!dev)
 411                 return NULL;
 412
 413         dev->config = config;
 414         if (odev)
 415                 device_replace(dev, odev);
 416
 417         if (!config_init && dev->config_pending)
 418                 type->config_init(dev);
 419
 420         return dev;
 421 }