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 void device_cleanup(struct device *dev)
 232 {
 233         struct device_user *dep, *tmp;
 234
 235         D(DEVICE, "Clean up device '%s'\n", dev->ifname);
 236         list_for_each_entry_safe(dep, tmp, &dev->users, list) {
 237                 if (!dep->cb)
 238                         continue;
 239
 240                 dep->cb(dep, DEV_EVENT_REMOVE);
 241         }
 242
 243         if (dev->avl.key)
 244                 avl_delete(&devices, &dev->avl);
 245 }
 246
 247 void device_set_present(struct device *dev, bool state)
 248 {
 249         if (dev->present == state)
 250                 return;
 251
 252         D(DEVICE, "Device '%s' %s present\n", dev->ifname, state ? "is now" : "is no longer" );
 253         dev->present = state;
 254         device_broadcast_event(dev, state ? DEV_EVENT_ADD : DEV_EVENT_REMOVE);
 255 }
 256
 257 void device_add_user(struct device_user *dep, struct device *dev)
 258 {
 259         dep->dev = dev;
 260         list_add_tail(&dep->list, &dev->users);
 261         if (dep->cb && dev->present) {
 262                 dep->cb(dep, DEV_EVENT_ADD);
 263                 if (dev->active)
 264                         dep->cb(dep, DEV_EVENT_UP);
 265         }
 266 }
 267
 268 static void
 269 __device_free_unused(struct device *dev)
 270 {
 271         if (!list_empty(&dev->users))
 272                 return;
 273
 274         device_free(dev);
 275 }
 276
 277 void device_remove_user(struct device_user *dep)
 278 {
 279         struct device *dev = dep->dev;
 280
 281         if (dep->claimed)
 282                 device_release(dep);
 283
 284         list_del(&dep->list);
 285         dep->dev = NULL;
 286         __device_free_unused(dev);
 287 }
 288
 289 void
 290 device_free_unused(struct device *dev)
 291 {
 292         struct device *tmp;
 293
 294         if (dev)
 295                 return __device_free_unused(dev);
 296
 297         avl_for_each_element_safe(&devices, dev, avl, tmp)
 298                 __device_free_unused(dev);
 299 }
 300
 301 enum dev_change_type
 302 device_reload_config(struct device *dev, struct blob_attr *attr)
 303 {
 304         struct blob_attr *tb[__DEV_ATTR_MAX], *tb1[__DEV_ATTR_MAX];
 305
 306         blobmsg_parse(dev_attrs, __DEV_ATTR_MAX, tb,
 307                 blob_data(attr), blob_len(attr));
 308         if (dev->config)
 309                 blobmsg_parse(dev_attrs, __DEV_ATTR_MAX, tb1,
 310                         blob_data(dev->config), blob_len(dev->config));
 311         else
 312                 memset(tb1, 0, sizeof(tb1));
 313
 314         if (!config_diff(tb, tb1, &device_attr_list, NULL))
 315                 return DEV_CONFIG_NO_CHANGE;
 316
 317         device_init_settings(dev, tb);
 318         return DEV_CONFIG_APPLIED;
 319 }
 320
 321 static enum dev_change_type
 322 device_check_config(struct device *dev, struct blob_attr *attr)
 323 {
 324         if (dev->type->reload)
 325                 return dev->type->reload(dev, attr);
 326
 327         return device_reload_config(dev, attr);
 328 }
 329
 330 static void
 331 device_replace(struct device *dev, struct device *odev)
 332 {
 333         struct device_user *dep, *tmp;
 334         bool present = odev->present;
 335
 336         if (present)
 337                 device_set_present(odev, false);
 338
 339         list_for_each_entry_safe(dep, tmp, &odev->users, list) {
 340                 device_remove_user(dep);
 341                 device_add_user(dep, dev);
 342         }
 343         device_free(odev);
 344
 345         if (present)
 346                 device_set_present(dev, true);
 347 }
 348
 349 struct device *
 350 device_create(const char *name, const struct device_type *type,
 351               struct blob_attr *config)
 352 {
 353         struct device *odev = NULL, *dev;
 354         enum dev_change_type change;
 355
 356         D(DEVICE, "Create new device '%s' (%s)\n", name, type->name);
 357         config = config_memdup(config);
 358         if (!config)
 359                 return NULL;
 360
 361         odev = device_get(name, false);
 362         if (odev) {
 363                 change = device_check_config(odev, config);
 364                 switch (change) {
 365                 case DEV_CONFIG_APPLIED:
 366                         free(odev->config);
 367                         odev->config = config;
 368                         if (odev->present) {
 369                                 device_set_present(odev, false);
 370                                 device_set_present(odev, true);
 371                         }
 372                         /* fall through */
 373                 case DEV_CONFIG_NO_CHANGE:
 374                         free(config);
 375                         return odev;
 376                 case DEV_CONFIG_RECREATE:
 377                         break;
 378                 }
 379         }
 380
 381         dev = type->create(config);
 382         dev->config = config;
 383         if (odev)
 384                 device_replace(dev, odev);
 385
 386         return dev;
 387 }