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