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