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
  18 #include "netifd.h"
  19 #include "system.h"
  20
  21 struct vlan_device {
  22         struct device dev;
  23         struct device_user dep;
  24
  25         device_state_cb set_state;
  26         int id;
  27 };
  28
  29 static void free_vlan_if(struct device *iface)
  30 {
  31         struct vlan_device *vldev;
  32
  33         vldev = container_of(iface, struct vlan_device, dev);
  34         device_remove_user(&vldev->dep);
  35         device_cleanup(&vldev->dev);
  36         free(vldev);
  37 }
  38
  39 static int vlan_set_device_state(struct device *dev, bool up)
  40 {
  41         struct vlan_device *vldev;
  42         int ret = 0;
  43
  44         vldev = container_of(dev, struct vlan_device, dev);
  45         if (!up) {
  46                 vldev->set_state(dev, false);
  47                 system_vlan_del(dev);
  48                 device_release(&vldev->dep);
  49                 return 0;
  50         }
  51
  52         ret = device_claim(&vldev->dep);
  53         if (ret)
  54                 return ret;
  55
  56         system_vlan_add(vldev->dep.dev, vldev->id);
  57         ret = vldev->set_state(dev, true);
  58         if (ret)
  59                 device_release(&vldev->dep);
  60
  61         return ret;
  62 }
  63
  64 static void vlan_dev_set_name(struct vlan_device *vldev, struct device *dev)
  65 {
  66         vldev->dev.hidden = dev->hidden;
  67         snprintf(vldev->dev.ifname, IFNAMSIZ, "%s.%d", dev->ifname, vldev->id);
  68 }
  69
  70 static void vlan_dev_cb(struct device_user *dep, enum device_event ev)
  71 {
  72         struct vlan_device *vldev;
  73         bool new_state = false;
  74
  75         vldev = container_of(dep, struct vlan_device, dep);
  76         switch(ev) {
  77         case DEV_EVENT_ADD:
  78                 new_state = true;
  79         case DEV_EVENT_REMOVE:
  80                 device_set_present(&vldev->dev, new_state);
  81                 break;
  82         case DEV_EVENT_LINK_UP:
  83                 new_state = true;
  84         case DEV_EVENT_LINK_DOWN:
  85                 device_set_link(&vldev->dev, new_state);
  86                 break;
  87         case DEV_EVENT_UPDATE_IFNAME:
  88                 vlan_dev_set_name(vldev, dep->dev);
  89                 device_broadcast_event(&vldev->dev, ev);
  90                 break;
  91         default:
  92                 break;
  93         }
  94 }
  95
  96 static struct device *get_vlan_device(struct device *dev, int id, bool create)
  97 {
  98         static const struct device_type vlan_type = {
  99                 .name = "VLAN",
 100                 .config_params = &device_attr_list,
 101                 .free = free_vlan_if,
 102         };
 103         struct vlan_device *vldev;
 104         struct device_user *dep;
 105
 106         /* look for an existing interface before creating a new one */
 107         list_for_each_entry(dep, &dev->users.list, list.list) {
 108                 if (dep->cb != vlan_dev_cb)
 109                         continue;
 110
 111                 vldev = container_of(dep, struct vlan_device, dep);
 112                 if (vldev->id != id)
 113                         continue;
 114
 115                 return &vldev->dev;
 116         }
 117
 118         if (!create)
 119                 return NULL;
 120
 121         D(DEVICE, "Create vlan device '%s.%d'\n", dev->ifname, id);
 122
 123         vldev = calloc(1, sizeof(*vldev));
 124
 125         vldev->id = id;
 126         vlan_dev_set_name(vldev, dev);
 127
 128         device_init_virtual(&vldev->dev, &vlan_type, NULL);
 129         vldev->dev.default_config = true;
 130
 131         vldev->set_state = vldev->dev.set_state;
 132         vldev->dev.set_state = vlan_set_device_state;
 133
 134         vldev->dep.cb = vlan_dev_cb;
 135         device_add_user(&vldev->dep, dev);
 136
 137         return &vldev->dev;
 138 }
 139
 140 static char *split_vlan(char *s)
 141 {
 142         s = strchr(s, '.');
 143         if (!s)
 144                 goto out;
 145
 146         *s = 0;
 147         s++;
 148
 149 out:
 150         return s;
 151 }
 152
 153 struct device *get_vlan_device_chain(const char *ifname, bool create)
 154 {
 155         struct device *dev = NULL;
 156         char *buf, *s, *next, *err = NULL;
 157         int id;
 158
 159         buf = strdup(ifname);
 160         if (!buf)
 161                 return NULL;
 162
 163         s = split_vlan(buf);
 164         dev = device_get(buf, create);
 165         if (!dev)
 166                 goto error;
 167
 168         do {
 169                 next = split_vlan(s);
 170                 id = strtoul(s, &err, 10);
 171                 if (err && *err)
 172                         goto error;
 173
 174                 dev = get_vlan_device(dev, id, create);
 175                 if (!dev)
 176                         goto error;
 177
 178                 s = next;
 179                 if (!s)
 180                         goto out;
 181         } while (1);
 182
 183 error:
 184         dev = NULL;
 185 out:
 186         free(buf);
 187         return dev;
 188 }