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 < 0)
  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         case DEV_EVENT_TOPO_CHANGE:
  92                 /* Propagate topo changes */
  93                 device_broadcast_event(&vldev->dev, DEV_EVENT_TOPO_CHANGE);
  94                 break;
  95         default:
  96                 break;
  97         }
  98 }
  99
 100 static struct device *get_vlan_device(struct device *dev, int id, bool create)
 101 {
 102         static const struct device_type vlan_type = {
 103                 .name = "VLAN",
 104                 .config_params = &device_attr_list,
 105                 .keep_link_status = true,
 106                 .free = free_vlan_if,
 107         };
 108         struct vlan_device *vldev;
 109         struct device_user *dep;
 110
 111         /* look for an existing interface before creating a new one */
 112         list_for_each_entry(dep, &dev->users.list, list.list) {
 113                 if (dep->cb != vlan_dev_cb)
 114                         continue;
 115
 116                 vldev = container_of(dep, struct vlan_device, dep);
 117                 if (vldev->id != id)
 118                         continue;
 119
 120                 return &vldev->dev;
 121         }
 122
 123         if (!create)
 124                 return NULL;
 125
 126         D(DEVICE, "Create vlan device '%s.%d'\n", dev->ifname, id);
 127
 128         vldev = calloc(1, sizeof(*vldev));
 129
 130         vldev->id = id;
 131         vlan_dev_set_name(vldev, dev);
 132
 133         device_init(&vldev->dev, &vlan_type, vldev->dev.ifname);
 134         vldev->dev.default_config = true;
 135
 136         vldev->set_state = vldev->dev.set_state;
 137         vldev->dev.set_state = vlan_set_device_state;
 138
 139         vldev->dep.cb = vlan_dev_cb;
 140         device_add_user(&vldev->dep, dev);
 141
 142         return &vldev->dev;
 143 }
 144
 145 static char *split_vlan(char *s)
 146 {
 147         s = strchr(s, '.');
 148         if (!s)
 149                 goto out;
 150
 151         *s = 0;
 152         s++;
 153
 154 out:
 155         return s;
 156 }
 157
 158 struct device *get_vlan_device_chain(const char *ifname, bool create)
 159 {
 160         struct device *dev = NULL;
 161         char *buf, *s, *next, *err = NULL;
 162         int id;
 163
 164         buf = strdup(ifname);
 165         if (!buf)
 166                 return NULL;
 167
 168         s = split_vlan(buf);
 169         dev = device_get(buf, create);
 170         if (!dev)
 171                 goto error;
 172
 173         do {
 174                 next = split_vlan(s);
 175                 id = strtoul(s, &err, 10);
 176                 if (err && *err)
 177                         goto error;
 178
 179                 dev = get_vlan_device(dev, id, create);
 180                 if (!dev)
 181                         goto error;
 182
 183                 s = next;
 184                 if (!s)
 185                         goto out;
 186         } while (1);
 187
 188 error:
 189         dev = NULL;
 190 out:
 191         free(buf);
 192         return dev;
 193 }