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         char name[IFNAMSIZ];
  67
  68         vldev->dev.hidden = dev->hidden;
  69         snprintf(name, IFNAMSIZ, "%s.%d", dev->ifname, vldev->id);
  70         device_set_ifname(&vldev->dev, name);
  71 }
  72
  73 static void vlan_dev_cb(struct device_user *dep, enum device_event ev)
  74 {
  75         struct vlan_device *vldev;
  76         bool new_state = false;
  77
  78         vldev = container_of(dep, struct vlan_device, dep);
  79         switch(ev) {
  80         case DEV_EVENT_ADD:
  81                 new_state = true;
  82         case DEV_EVENT_REMOVE:
  83                 device_set_present(&vldev->dev, new_state);
  84                 break;
  85         case DEV_EVENT_UPDATE_IFNAME:
  86                 vlan_dev_set_name(vldev, dep->dev);
  87                 break;
  88         case DEV_EVENT_TOPO_CHANGE:
  89                 /* Propagate topo changes */
  90                 device_broadcast_event(&vldev->dev, DEV_EVENT_TOPO_CHANGE);
  91                 break;
  92         default:
  93                 break;
  94         }
  95 }
  96
  97 static struct device *get_vlan_device(struct device *dev, int id, bool create)
  98 {
  99         static struct device_type vlan_type = {
 100                 .name = "VLAN",
 101                 .config_params = &device_attr_list,
 102                 .free = free_vlan_if,
 103         };
 104         struct vlan_device *vldev;
 105         struct device_user *dep;
 106
 107         /* look for an existing interface before creating a new one */
 108         list_for_each_entry(dep, &dev->users.list, list.list) {
 109                 if (dep->cb != vlan_dev_cb)
 110                         continue;
 111
 112                 vldev = container_of(dep, struct vlan_device, dep);
 113                 if (vldev->id != id)
 114                         continue;
 115
 116                 return &vldev->dev;
 117         }
 118
 119         if (!create)
 120                 return NULL;
 121
 122         D(DEVICE, "Create vlan device '%s.%d'\n", dev->ifname, id);
 123
 124         vldev = calloc(1, sizeof(*vldev));
 125         if (!vldev)
 126                 return NULL;
 127
 128         vldev->id = id;
 129
 130         device_init(&vldev->dev, &vlan_type, NULL);
 131
 132         vlan_dev_set_name(vldev, dev);
 133         vldev->dev.default_config = true;
 134
 135         vldev->set_state = vldev->dev.set_state;
 136         vldev->dev.set_state = vlan_set_device_state;
 137
 138         vldev->dep.cb = vlan_dev_cb;
 139         device_add_user(&vldev->dep, dev);
 140
 141         return &vldev->dev;
 142 }
 143
 144 static char *split_vlan(char *s)
 145 {
 146         s = strchr(s, '.');
 147         if (!s)
 148                 goto out;
 149
 150         *s = 0;
 151         s++;
 152
 153 out:
 154         return s;
 155 }
 156
 157 struct device *get_vlan_device_chain(const char *ifname, bool create)
 158 {
 159         struct device *dev = NULL;
 160         char *buf, *s, *next, *err = NULL;
 161         int id;
 162
 163         buf = strdup(ifname);
 164         if (!buf)
 165                 return NULL;
 166
 167         s = split_vlan(buf);
 168         dev = device_get(buf, create);
 169         if (!dev)
 170                 goto error;
 171
 172         do {
 173                 next = split_vlan(s);
 174                 id = strtoul(s, &err, 10);
 175                 if (err && *err)
 176                         goto error;
 177
 178                 dev = get_vlan_device(dev, id, create);
 179                 if (!dev)
 180                         goto error;
 181
 182                 s = next;
 183                 if (!s)
 184                         goto out;
 185         } while (1);
 186
 187 error:
 188         dev = NULL;
 189 out:
 190         free(buf);
 191         return dev;
 192 }