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 int vlan_dev_set_name(struct vlan_device *vldev, struct device *dev)
  65 {
  66         char *name;
  67
  68         name = alloca(strlen(dev->ifname) + sizeof(".2147483647\0"));
  69         vldev->dev.hidden = dev->hidden;
  70         sprintf(name, "%s.%d", dev->ifname, vldev->id);
  71
  72         return device_set_ifname(&vldev->dev, name);
  73 }
  74
  75 static void vlan_dev_cb(struct device_user *dep, enum device_event ev)
  76 {
  77         struct vlan_device *vldev;
  78
  79         vldev = container_of(dep, struct vlan_device, dep);
  80         switch(ev) {
  81         case DEV_EVENT_ADD:
  82                 device_set_present(&vldev->dev, true);
  83                 break;
  84         case DEV_EVENT_REMOVE:
  85                 device_set_present(&vldev->dev, false);
  86                 break;
  87         case DEV_EVENT_UPDATE_IFNAME:
  88                 if (vlan_dev_set_name(vldev, dep->dev) < 0)
  89                         free_vlan_if(&vldev->dev);
  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 struct device_type vlan_type = {
 103                 .name = "VLAN",
 104                 .config_params = &device_attr_list,
 105                 .free = free_vlan_if,
 106         };
 107         struct vlan_device *vldev;
 108         struct device_user *dep;
 109
 110         /* look for an existing interface before creating a new one */
 111         list_for_each_entry(dep, &dev->users.list, list.list) {
 112                 if (dep->cb != vlan_dev_cb)
 113                         continue;
 114
 115                 vldev = container_of(dep, struct vlan_device, dep);
 116                 if (vldev->id != id)
 117                         continue;
 118
 119                 return &vldev->dev;
 120         }
 121
 122         if (!create)
 123                 return NULL;
 124
 125         D(DEVICE, "Create vlan device '%s.%d'\n", dev->ifname, id);
 126
 127         vldev = calloc(1, sizeof(*vldev));
 128         if (!vldev)
 129                 return NULL;
 130
 131         vldev->id = id;
 132
 133         if (device_init(&vldev->dev, &vlan_type, NULL) < 0)
 134                 goto error;
 135
 136         if (vlan_dev_set_name(vldev, dev) < 0)
 137                 goto error;
 138
 139         vldev->dev.default_config = true;
 140
 141         vldev->set_state = vldev->dev.set_state;
 142         vldev->dev.set_state = vlan_set_device_state;
 143
 144         vldev->dep.cb = vlan_dev_cb;
 145         device_add_user(&vldev->dep, dev);
 146
 147         return &vldev->dev;
 148
 149 error:
 150         device_cleanup(&vldev->dev);
 151         free(vldev);
 152         return NULL;
 153 }
 154
 155 static char *split_vlan(char *s)
 156 {
 157         s = strchr(s, '.');
 158         if (!s)
 159                 goto out;
 160
 161         *s = 0;
 162         s++;
 163
 164 out:
 165         return s;
 166 }
 167
 168 struct device *get_vlan_device_chain(const char *ifname, bool create)
 169 {
 170         struct device *dev = NULL;
 171         char *buf, *s, *next, *err = NULL;
 172         int id;
 173
 174         buf = strdup(ifname);
 175         if (!buf)
 176                 return NULL;
 177
 178         s = split_vlan(buf);
 179         dev = device_get(buf, create);
 180         if (!dev)
 181                 goto error;
 182
 183         do {
 184                 next = split_vlan(s);
 185                 id = strtoul(s, &err, 10);
 186                 if (err && *err)
 187                         goto error;
 188
 189                 dev = get_vlan_device(dev, id, create);
 190                 if (!dev)
 191                         goto error;
 192
 193                 s = next;
 194                 if (!s)
 195                         goto out;
 196         } while (1);
 197
 198 error:
 199         dev = NULL;
 200 out:
 201         free(buf);
 202         return dev;
 203 }