vlan.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 <ctype.h>
  18
  19 #include "netifd.h"
  20 #include "system.h"
  21
  22 static struct blob_buf b;
  23
  24 struct vlan_device {
  25         struct device dev;
  26         struct device_user dep;
  27
  28         device_state_cb set_state;
  29         int id;
  30 };
  31
  32 static void free_vlan_if(struct device *iface)
  33 {
  34         struct vlan_device *vldev;
  35
  36         vldev = container_of(iface, struct vlan_device, dev);
  37         device_remove_user(&vldev->dep);
  38         device_cleanup(&vldev->dev);
  39         free(vldev);
  40 }
  41
  42 static int
  43 __vlan_hotplug_op(struct device *dev, struct device *member, struct blob_attr *vlan, bool add)
  44 {
  45         struct vlan_device *vldev = container_of(dev, struct vlan_device, dev);
  46         void *a;
  47
  48         dev = vldev->dep.dev;
  49         if (!dev || !dev->hotplug_ops)
  50                 return UBUS_STATUS_NOT_SUPPORTED;
  51
  52         blob_buf_init(&b, 0);
  53         a = blobmsg_open_array(&b, "vlans");
  54         blobmsg_printf(&b, NULL, "%d", vldev->id);
  55         blobmsg_close_array(&b, a);
  56
  57         if (add)
  58                 return dev->hotplug_ops->add(dev, member, blobmsg_data(b.head));
  59         else
  60                 return dev->hotplug_ops->del(dev, member, blobmsg_data(b.head));
  61 }
  62
  63 static int
  64 vlan_hotplug_add(struct device *dev, struct device *member, struct blob_attr *vlan)
  65 {
  66         return __vlan_hotplug_op(dev, member, vlan, true);
  67 }
  68
  69 static int
  70 vlan_hotplug_del(struct device *dev, struct device *member, struct blob_attr *vlan)
  71 {
  72         return __vlan_hotplug_op(dev, member, vlan, false);
  73 }
  74
  75 static int
  76 vlan_hotplug_prepare(struct device *dev, struct device **bridge_dev)
  77 {
  78         struct vlan_device *vldev = container_of(dev, struct vlan_device, dev);
  79
  80         dev = vldev->dep.dev;
  81         if (!dev || !dev->hotplug_ops)
  82                 return UBUS_STATUS_NOT_SUPPORTED;
  83
  84         return dev->hotplug_ops->prepare(dev, bridge_dev);
  85 }
  86
  87 static void vlan_hotplug_check(struct vlan_device *vldev, struct device *dev)
  88 {
  89         static const struct device_hotplug_ops hotplug_ops = {
  90                 .prepare = vlan_hotplug_prepare,
  91                 .add = vlan_hotplug_add,
  92                 .del = vlan_hotplug_del
  93         };
  94
  95         if (!dev || !dev->hotplug_ops || avl_is_empty(&dev->vlans.avl)) {
  96                 vldev->dev.hotplug_ops = NULL;
  97                 return;
  98         }
  99
 100         vldev->dev.hotplug_ops = &hotplug_ops;
 101 }
 102
 103
 104 static int vlan_set_device_state(struct device *dev, bool up)
 105 {
 106         struct vlan_device *vldev;
 107         int ret = 0;
 108
 109         vldev = container_of(dev, struct vlan_device, dev);
 110         if (!up) {
 111                 vldev->set_state(dev, false);
 112                 system_vlan_del(dev);
 113                 device_release(&vldev->dep);
 114                 return 0;
 115         }
 116
 117         ret = device_claim(&vldev->dep);
 118         if (ret < 0)
 119                 return ret;
 120
 121         system_vlan_add(vldev->dep.dev, vldev->id);
 122         ret = vldev->set_state(dev, true);
 123         if (ret)
 124                 device_release(&vldev->dep);
 125
 126         return ret;
 127 }
 128
 129 static void vlan_dev_cb(struct device_user *dep, enum device_event ev)
 130 {
 131         char name[IFNAMSIZ + 1];
 132         struct vlan_device *vldev;
 133
 134         vldev = container_of(dep, struct vlan_device, dep);
 135         switch(ev) {
 136         case DEV_EVENT_ADD:
 137                 device_set_present(&vldev->dev, true);
 138                 break;
 139         case DEV_EVENT_REMOVE:
 140                 device_set_present(&vldev->dev, false);
 141                 break;
 142         case DEV_EVENT_UPDATE_IFNAME:
 143                 vlan_hotplug_check(vldev, dep->dev);
 144                 vldev->dev.hidden = dep->dev->hidden;
 145                 if (snprintf(name, sizeof(name), "%s.%d", dep->dev->ifname,
 146                              vldev->id) >= sizeof(name) - 1 ||
 147                     device_set_ifname(&vldev->dev, name))
 148                         free_vlan_if(&vldev->dev);
 149                 break;
 150         case DEV_EVENT_TOPO_CHANGE:
 151                 /* Propagate topo changes */
 152                 device_broadcast_event(&vldev->dev, DEV_EVENT_TOPO_CHANGE);
 153                 break;
 154         default:
 155                 break;
 156         }
 157 }
 158
 159 static void
 160 vlan_config_init(struct device *dev)
 161 {
 162         struct vlan_device *vldev;
 163
 164         vldev = container_of(dev, struct vlan_device, dev);
 165         vlan_hotplug_check(vldev, vldev->dep.dev);
 166 }
 167
 168 static struct device *get_vlan_device(struct device *dev, char *id_str, bool create)
 169 {
 170         static struct device_type vlan_type = {
 171                 .name = "VLAN",
 172                 .config_params = &device_attr_list,
 173                 .config_init = vlan_config_init,
 174                 .free = free_vlan_if,
 175         };
 176         struct vlan_device *vldev;
 177         struct device_user *dep;
 178         char name[IFNAMSIZ + 1];
 179         char *err = NULL;
 180         int id, *alias_id;
 181
 182         id = strtoul(id_str, &err, 10);
 183         if (err && *err) {
 184                 alias_id = kvlist_get(&dev->vlan_aliases, id_str);
 185                 if (!alias_id)
 186                         return NULL;
 187
 188                 id = *alias_id;
 189         }
 190
 191         /* look for an existing interface before creating a new one */
 192         list_for_each_entry(dep, &dev->users.list, list.list) {
 193                 if (dep->cb != vlan_dev_cb)
 194                         continue;
 195
 196                 vldev = container_of(dep, struct vlan_device, dep);
 197                 if (vldev->id != id)
 198                         continue;
 199
 200                 return &vldev->dev;
 201         }
 202
 203         if (!create)
 204                 return NULL;
 205
 206         if (snprintf(name, sizeof(name), "%s.%d", dev->ifname, id) >= sizeof(name) - 1)
 207                 return NULL;
 208
 209         D(DEVICE, "Create vlan device '%s'\n", name);
 210
 211         vldev = calloc(1, sizeof(*vldev));
 212         if (!vldev)
 213                 return NULL;
 214
 215         vldev->id = id;
 216         vldev->dev.hidden = dev->hidden;
 217         strcpy(vldev->dev.ifname, name);
 218
 219         if (device_init(&vldev->dev, &vlan_type, NULL) < 0)
 220                 goto error;
 221
 222         vldev->dev.default_config = true;
 223         vldev->dev.config_pending = true;
 224
 225         vldev->set_state = vldev->dev.set_state;
 226         vldev->dev.set_state = vlan_set_device_state;
 227
 228         vldev->dep.cb = vlan_dev_cb;
 229         vlan_hotplug_check(vldev, vldev->dep.dev);
 230         device_add_user(&vldev->dep, dev);
 231
 232         return &vldev->dev;
 233
 234 error:
 235         device_cleanup(&vldev->dev);
 236         free(vldev);
 237         return NULL;
 238 }
 239
 240 static char *split_vlan(char *s)
 241 {
 242         s = strchr(s, '.');
 243         if (!s)
 244                 return NULL;
 245
 246         *s = 0;
 247         s++;
 248
 249         return s;
 250 }
 251
 252 struct device *get_vlan_device_chain(const char *ifname, int create)
 253 {
 254         struct device *dev = NULL, *vldev;
 255         char *buf, *s, *next;
 256
 257         buf = strdup(ifname);
 258         if (!buf)
 259                 return NULL;
 260
 261         s = split_vlan(buf);
 262         dev = __device_get(buf, create, false);
 263         if (!dev || !s)
 264                 goto out;
 265
 266         /* for the first split, we need to check if we're using an alias or
 267          * if the . separator isn't being used as a vlan separator (e.g. for
 268          * AP WDS VLANs */
 269         if (!isdigit(s[0])) {
 270                 next = split_vlan(s);
 271                 vldev = get_vlan_device(dev, s, create);
 272                 if (!vldev) {
 273                         s[-1] = '.';
 274                         dev = __device_get(buf, create, false);
 275                         if (!dev)
 276                                 goto out;
 277
 278                         if (next)
 279                                 next[-1] = '.';
 280                 } else {
 281                         dev = vldev;
 282                         s = next;
 283                 }
 284         }
 285
 286
 287         while (s) {
 288                 next = split_vlan(s);
 289                 dev = get_vlan_device(dev, s, create);
 290                 if (!dev)
 291                         break;
 292
 293                 s = next;
 294         }
 295
 296 out:
 297         free(buf);
 298         return dev;
 299 }