vlan.c

   1 #include <string.h>
   2 #include <stdlib.h>
   3 #include <stdio.h>
   4
   5 #include "netifd.h"
   6 #include "system.h"
   7
   8 struct vlan_device {
   9         struct device dev;
  10         struct device_user dep;
  11
  12         device_state_cb set_state;
  13         int id;
  14 };
  15
  16 static void free_vlan_if(struct device *iface)
  17 {
  18         struct vlan_device *vldev;
  19
  20         vldev = container_of(iface, struct vlan_device, dev);
  21         device_remove_user(&vldev->dep);
  22         cleanup_device(&vldev->dev);
  23         free(vldev);
  24 }
  25
  26 static int vlan_set_device_state(struct device *dev, bool up)
  27 {
  28         struct vlan_device *vldev;
  29         int ret = 0;
  30
  31         vldev = container_of(dev, struct vlan_device, dev);
  32         if (!up) {
  33                 vldev->set_state(dev, false);
  34                 system_vlan_del(dev);
  35                 release_device(vldev->dep.dev);
  36                 return 0;
  37         }
  38
  39         ret = claim_device(vldev->dep.dev);
  40         if (ret)
  41                 return ret;
  42
  43         system_vlan_add(vldev->dep.dev, vldev->id);
  44         ret = vldev->set_state(dev, true);
  45         if (ret)
  46                 release_device(vldev->dep.dev);
  47
  48         return ret;
  49 }
  50
  51 static void vlan_dev_cb(struct device_user *dep, enum device_event ev)
  52 {
  53         struct vlan_device *vldev;
  54
  55         vldev = container_of(dep, struct vlan_device, dep);
  56         switch(ev) {
  57         case DEV_EVENT_ADD:
  58                 set_device_present(&vldev->dev, true);
  59                 break;
  60         case DEV_EVENT_REMOVE:
  61                 set_device_present(&vldev->dev, false);
  62                 break;
  63         default:
  64                 break;
  65         }
  66 }
  67
  68 static struct device *get_vlan_device(struct device *dev, int id, bool create)
  69 {
  70         static const struct device_type vlan_type = {
  71                 .name = "VLAN",
  72                 .free = free_vlan_if,
  73         };
  74         struct vlan_device *vldev;
  75         struct device_user *dep;
  76
  77         /* look for an existing interface before creating a new one */
  78         list_for_each_entry(dep, &dev->users, list) {
  79                 if (dep->cb != vlan_dev_cb)
  80                         continue;
  81
  82                 vldev = container_of(dep, struct vlan_device, dep);
  83                 if (vldev->id != id)
  84                         continue;
  85
  86                 return &vldev->dev;
  87         }
  88
  89         if (!create)
  90                 return NULL;
  91
  92         vldev = calloc(1, sizeof(*vldev));
  93         snprintf(vldev->dev.ifname, IFNAMSIZ, "%s.%d", dev->ifname, id);
  94
  95         init_device(&vldev->dev, &vlan_type, NULL);
  96
  97         vldev->set_state = vldev->dev.set_state;
  98         vldev->dev.set_state = vlan_set_device_state;
  99
 100         vldev->id = id;
 101
 102         vldev->dep.cb = vlan_dev_cb;
 103         add_device_user(&vldev->dep, dev);
 104
 105         return &vldev->dev;
 106 }
 107
 108 static char *split_vlan(char *s)
 109 {
 110         s = strchr(s, '.');
 111         if (!s)
 112                 goto out;
 113
 114         *s = 0;
 115         s++;
 116
 117 out:
 118         return s;
 119 }
 120
 121 struct device *get_vlan_device_chain(const char *ifname, bool create)
 122 {
 123         struct device *iface = NULL;
 124         char *buf, *s, *next, *err = NULL;
 125         int id;
 126
 127         buf = strdup(ifname);
 128         if (!buf)
 129                 return NULL;
 130
 131         s = split_vlan(buf);
 132         iface = get_device(buf, create);
 133         if (!iface && !create)
 134                 goto error;
 135
 136         do {
 137                 next = split_vlan(s);
 138                 id = strtoul(s, &err, 10);
 139                 if (err && *err)
 140                         goto error;
 141
 142                 iface = get_vlan_device(iface, id, create);
 143                 if (!iface)
 144                         goto error;
 145
 146                 s = next;
 147                 if (!s)
 148                         goto out;
 149         } while (1);
 150
 151 error:
 152         iface = NULL;
 153 out:
 154         free(buf);
 155         return iface;
 156 }