add prelocal table to manipulate locally destinated traffic
[project/netifd.git] / 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_LINK_UP:
83                 new_state = true;
84         case DEV_EVENT_LINK_DOWN:
85                 device_set_link(&vldev->dev, new_state);
86                 break;
87         case DEV_EVENT_UPDATE_IFNAME:
88                 vlan_dev_set_name(vldev, dep->dev);
89                 device_broadcast_event(&vldev->dev, ev);
90                 break;
91         case DEV_EVENT_TOPO_CHANGE:
92                 /* Propagate topo changes */
93                 device_broadcast_event(&vldev->dev, DEV_EVENT_TOPO_CHANGE);
94                 break;
95         default:
96                 break;
97         }
98 }
99
100 static struct device *get_vlan_device(struct device *dev, int id, bool create)
101 {
102         static const struct device_type vlan_type = {
103                 .name = "VLAN",
104                 .config_params = &device_attr_list,
105                 .keep_link_status = true,
106                 .free = free_vlan_if,
107         };
108         struct vlan_device *vldev;
109         struct device_user *dep;
110
111         /* look for an existing interface before creating a new one */
112         list_for_each_entry(dep, &dev->users.list, list.list) {
113                 if (dep->cb != vlan_dev_cb)
114                         continue;
115
116                 vldev = container_of(dep, struct vlan_device, dep);
117                 if (vldev->id != id)
118                         continue;
119
120                 return &vldev->dev;
121         }
122
123         if (!create)
124                 return NULL;
125
126         D(DEVICE, "Create vlan device '%s.%d'\n", dev->ifname, id);
127
128         vldev = calloc(1, sizeof(*vldev));
129
130         vldev->id = id;
131         vlan_dev_set_name(vldev, dev);
132
133         device_init_virtual(&vldev->dev, &vlan_type, NULL);
134         vldev->dev.default_config = true;
135
136         vldev->set_state = vldev->dev.set_state;
137         vldev->dev.set_state = vlan_set_device_state;
138
139         vldev->dep.cb = vlan_dev_cb;
140         device_add_user(&vldev->dep, dev);
141
142         return &vldev->dev;
143 }
144
145 static char *split_vlan(char *s)
146 {
147         s = strchr(s, '.');
148         if (!s)
149                 goto out;
150
151         *s = 0;
152         s++;
153
154 out:
155         return s;
156 }
157
158 struct device *get_vlan_device_chain(const char *ifname, bool create)
159 {
160         struct device *dev = NULL;
161         char *buf, *s, *next, *err = NULL;
162         int id;
163
164         buf = strdup(ifname);
165         if (!buf)
166                 return NULL;
167
168         s = split_vlan(buf);
169         dev = device_get(buf, create);
170         if (!dev)
171                 goto error;
172
173         do {
174                 next = split_vlan(s);
175                 id = strtoul(s, &err, 10);
176                 if (err && *err)
177                         goto error;
178
179                 dev = get_vlan_device(dev, id, create);
180                 if (!dev)
181                         goto error;
182
183                 s = next;
184                 if (!s)
185                         goto out;
186         } while (1);
187
188 error:
189         dev = NULL;
190 out:
191         free(buf);
192         return dev;
193 }