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_cb(struct device_user *dep, enum device_event ev)
  65 {
  66         char name[IFNAMSIZ + 1];
  67         struct vlan_device *vldev;
  68
  69         vldev = container_of(dep, struct vlan_device, dep);
  70         switch(ev) {
  71         case DEV_EVENT_ADD:
  72                 device_set_present(&vldev->dev, true);
  73                 break;
  74         case DEV_EVENT_REMOVE:
  75                 device_set_present(&vldev->dev, false);
  76                 break;
  77         case DEV_EVENT_UPDATE_IFNAME:
  78                 vldev->dev.hidden = dep->dev->hidden;
  79                 if (snprintf(name, sizeof(name), "%s.%d", dep->dev->ifname,
  80                              vldev->id) >= sizeof(name) - 1 ||
  81                     device_set_ifname(&vldev->dev, name))
  82                         free_vlan_if(&vldev->dev);
  83                 break;
  84         case DEV_EVENT_TOPO_CHANGE:
  85                 /* Propagate topo changes */
  86                 device_broadcast_event(&vldev->dev, DEV_EVENT_TOPO_CHANGE);
  87                 break;
  88         default:
  89                 break;
  90         }
  91 }
  92
  93 static struct device *get_vlan_device(struct device *dev, int id, bool create)
  94 {
  95         static struct device_type vlan_type = {
  96                 .name = "VLAN",
  97                 .config_params = &device_attr_list,
  98                 .free = free_vlan_if,
  99         };
 100         struct vlan_device *vldev;
 101         struct device_user *dep;
 102         char name[IFNAMSIZ + 1];
 103
 104         /* look for an existing interface before creating a new one */
 105         list_for_each_entry(dep, &dev->users.list, list.list) {
 106                 if (dep->cb != vlan_dev_cb)
 107                         continue;
 108
 109                 vldev = container_of(dep, struct vlan_device, dep);
 110                 if (vldev->id != id)
 111                         continue;
 112
 113                 return &vldev->dev;
 114         }
 115
 116         if (!create)
 117                 return NULL;
 118
 119         if (snprintf(name, sizeof(name), "%s.%d", dev->ifname, id) >= sizeof(name) - 1)
 120                 return NULL;
 121
 122         D(DEVICE, "Create vlan device '%s'\n", name);
 123
 124         vldev = calloc(1, sizeof(*vldev));
 125         if (!vldev)
 126                 return NULL;
 127
 128         vldev->id = id;
 129         vldev->dev.hidden = dev->hidden;
 130         strcpy(vldev->dev.ifname, name);
 131
 132         if (device_init(&vldev->dev, &vlan_type, NULL) < 0)
 133                 goto error;
 134
 135         vldev->dev.default_config = true;
 136
 137         vldev->set_state = vldev->dev.set_state;
 138         vldev->dev.set_state = vlan_set_device_state;
 139
 140         vldev->dep.cb = vlan_dev_cb;
 141         device_add_user(&vldev->dep, dev);
 142
 143         return &vldev->dev;
 144
 145 error:
 146         device_cleanup(&vldev->dev);
 147         free(vldev);
 148         return NULL;
 149 }
 150
 151 static char *split_vlan(char *s)
 152 {
 153         s = strchr(s, '.');
 154         if (!s)
 155                 goto out;
 156
 157         *s = 0;
 158         s++;
 159
 160 out:
 161         return s;
 162 }
 163
 164 struct device *get_vlan_device_chain(const char *ifname, bool create)
 165 {
 166         struct device *dev = NULL;
 167         char *buf, *s, *next, *err = NULL;
 168         int id;
 169
 170         buf = strdup(ifname);
 171         if (!buf)
 172                 return NULL;
 173
 174         s = split_vlan(buf);
 175         dev = device_get(buf, create);
 176         if (!dev)
 177                 goto error;
 178
 179         do {
 180                 next = split_vlan(s);
 181                 id = strtoul(s, &err, 10);
 182                 if (err && *err)
 183                         goto error;
 184
 185                 dev = get_vlan_device(dev, id, create);
 186                 if (!dev)
 187                         goto error;
 188
 189                 s = next;
 190                 if (!s)
 191                         goto out;
 192         } while (1);
 193
 194 error:
 195         dev = NULL;
 196 out:
 197         free(buf);
 198         return dev;
 199 }