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;
  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         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                 vlan_dev_set_name(vldev, dep->dev);
  89                 break;
  90         case DEV_EVENT_TOPO_CHANGE:
  91                 /* Propagate topo changes */
  92                 device_broadcast_event(&vldev->dev, DEV_EVENT_TOPO_CHANGE);
  93                 break;
  94         default:
  95                 break;
  96         }
  97 }
  98
  99 static struct device *get_vlan_device(struct device *dev, int id, bool create)
 100 {
 101         static struct device_type vlan_type = {
 102                 .name = "VLAN",
 103                 .config_params = &device_attr_list,
 104                 .free = free_vlan_if,
 105         };
 106         struct vlan_device *vldev;
 107         struct device_user *dep;
 108
 109         /* look for an existing interface before creating a new one */
 110         list_for_each_entry(dep, &dev->users.list, list.list) {
 111                 if (dep->cb != vlan_dev_cb)
 112                         continue;
 113
 114                 vldev = container_of(dep, struct vlan_device, dep);
 115                 if (vldev->id != id)
 116                         continue;
 117
 118                 return &vldev->dev;
 119         }
 120
 121         if (!create)
 122                 return NULL;
 123
 124         D(DEVICE, "Create vlan device '%s.%d'\n", dev->ifname, id);
 125
 126         vldev = calloc(1, sizeof(*vldev));
 127         if (!vldev)
 128                 return NULL;
 129
 130         vldev->id = id;
 131
 132         device_init(&vldev->dev, &vlan_type, NULL);
 133
 134         vlan_dev_set_name(vldev, dev);
 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
 146 static char *split_vlan(char *s)
 147 {
 148         s = strchr(s, '.');
 149         if (!s)
 150                 goto out;
 151
 152         *s = 0;
 153         s++;
 154
 155 out:
 156         return s;
 157 }
 158
 159 struct device *get_vlan_device_chain(const char *ifname, bool create)
 160 {
 161         struct device *dev = NULL;
 162         char *buf, *s, *next, *err = NULL;
 163         int id;
 164
 165         buf = strdup(ifname);
 166         if (!buf)
 167                 return NULL;
 168
 169         s = split_vlan(buf);
 170         dev = device_get(buf, create);
 171         if (!dev)
 172                 goto error;
 173
 174         do {
 175                 next = split_vlan(s);
 176                 id = strtoul(s, &err, 10);
 177                 if (err && *err)
 178                         goto error;
 179
 180                 dev = get_vlan_device(dev, id, create);
 181                 if (!dev)
 182                         goto error;
 183
 184                 s = next;
 185                 if (!s)
 186                         goto out;
 187         } while (1);
 188
 189 error:
 190         dev = NULL;
 191 out:
 192         free(buf);
 193         return dev;
 194 }