1/*
2 * hostapd / VLAN netlink api
3 * Copyright (c) 2012, Michael Braun <michael-dev@fami-braun.de>
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9#include "utils/includes.h"
10#include <sys/ioctl.h>
11#include <linux/sockios.h>
12#include <linux/if_vlan.h>
13#include <netlink/genl/genl.h>
14#include <netlink/genl/family.h>
15#include <netlink/genl/ctrl.h>
16#include <netlink/route/link.h>
17#include <netlink/route/link/vlan.h>
18
19#include "utils/common.h"
20#include "utils/eloop.h"
21#include "hostapd.h"
22#include "vlan_util.h"
23
24/*
25 * Add a vlan interface with name 'vlan_if_name', VLAN ID 'vid' and
26 * tagged interface 'if_name'.
27 *
28 * returns -1 on error
29 * returns 1 if the interface already exists
30 * returns 0 otherwise
31*/
32int vlan_add(const char *if_name, int vid, const char *vlan_if_name)
33{
34	int ret = -1;
35	struct nl_sock *handle = NULL;
36	struct nl_cache *cache = NULL;
37	struct rtnl_link *rlink = NULL;
38	int if_idx = 0;
39
40	wpa_printf(MSG_DEBUG, "VLAN: vlan_add(if_name=%s, vid=%d, "
41		   "vlan_if_name=%s)", if_name, vid, vlan_if_name);
42
43	if ((os_strlen(if_name) + 1) > IFNAMSIZ) {
44		wpa_printf(MSG_ERROR, "VLAN: Interface name too long: '%s'",
45			   if_name);
46		return -1;
47	}
48
49	if ((os_strlen(vlan_if_name) + 1) > IFNAMSIZ) {
50		wpa_printf(MSG_ERROR, "VLAN: Interface name too long: '%s'",
51			   vlan_if_name);
52		return -1;
53	}
54
55	handle = nl_socket_alloc();
56	if (!handle) {
57		wpa_printf(MSG_ERROR, "VLAN: failed to open netlink socket");
58		goto vlan_add_error;
59	}
60
61	if (nl_connect(handle, NETLINK_ROUTE) < 0) {
62		wpa_printf(MSG_ERROR, "VLAN: failed to connect to netlink");
63		goto vlan_add_error;
64	}
65
66	if (rtnl_link_alloc_cache(handle, AF_UNSPEC, &cache) < 0) {
67		cache = NULL;
68		wpa_printf(MSG_ERROR, "VLAN: failed to alloc cache");
69		goto vlan_add_error;
70	}
71
72	if (!(if_idx = rtnl_link_name2i(cache, if_name))) {
73		/* link does not exist */
74		wpa_printf(MSG_ERROR, "VLAN: interface %s does not exist",
75			   if_name);
76		goto vlan_add_error;
77	}
78
79	if ((rlink = rtnl_link_get_by_name(cache, vlan_if_name))) {
80		/* link does exist */
81		rtnl_link_put(rlink);
82		rlink = NULL;
83		wpa_printf(MSG_ERROR, "VLAN: interface %s already exists",
84			   vlan_if_name);
85		ret = 1;
86		goto vlan_add_error;
87	}
88
89	rlink = rtnl_link_alloc();
90	if (!rlink) {
91		wpa_printf(MSG_ERROR, "VLAN: failed to allocate new link");
92		goto vlan_add_error;
93	}
94
95	if (rtnl_link_set_type(rlink, "vlan") < 0) {
96		wpa_printf(MSG_ERROR, "VLAN: failed to set link type");
97		goto vlan_add_error;
98	}
99
100	rtnl_link_set_link(rlink, if_idx);
101	rtnl_link_set_name(rlink, vlan_if_name);
102
103	if (rtnl_link_vlan_set_id(rlink, vid) < 0) {
104		wpa_printf(MSG_ERROR, "VLAN: failed to set link vlan id");
105		goto vlan_add_error;
106	}
107
108	if (rtnl_link_add(handle, rlink, NLM_F_CREATE) < 0) {
109		wpa_printf(MSG_ERROR, "VLAN: failed to create link %s for "
110			   "vlan %d on %s (%d)",
111			   vlan_if_name, vid, if_name, if_idx);
112		goto vlan_add_error;
113	}
114
115	ret = 0;
116
117vlan_add_error:
118	if (rlink)
119		rtnl_link_put(rlink);
120	if (cache)
121		nl_cache_free(cache);
122	if (handle)
123		nl_socket_free(handle);
124	return ret;
125}
126
127
128int vlan_rem(const char *if_name)
129{
130	int ret = -1;
131	struct nl_sock *handle = NULL;
132	struct nl_cache *cache = NULL;
133	struct rtnl_link *rlink = NULL;
134
135	wpa_printf(MSG_DEBUG, "VLAN: vlan_rem(if_name=%s)", if_name);
136
137	handle = nl_socket_alloc();
138	if (!handle) {
139		wpa_printf(MSG_ERROR, "VLAN: failed to open netlink socket");
140		goto vlan_rem_error;
141	}
142
143	if (nl_connect(handle, NETLINK_ROUTE) < 0) {
144		wpa_printf(MSG_ERROR, "VLAN: failed to connect to netlink");
145		goto vlan_rem_error;
146	}
147
148	if (rtnl_link_alloc_cache(handle, AF_UNSPEC, &cache) < 0) {
149		cache = NULL;
150		wpa_printf(MSG_ERROR, "VLAN: failed to alloc cache");
151		goto vlan_rem_error;
152	}
153
154	if (!(rlink = rtnl_link_get_by_name(cache, if_name))) {
155		/* link does not exist */
156		wpa_printf(MSG_ERROR, "VLAN: interface %s does not exists",
157			   if_name);
158		goto vlan_rem_error;
159	}
160
161	if (rtnl_link_delete(handle, rlink) < 0) {
162		wpa_printf(MSG_ERROR, "VLAN: failed to remove link %s",
163			   if_name);
164		goto vlan_rem_error;
165	}
166
167	ret = 0;
168
169vlan_rem_error:
170	if (rlink)
171		rtnl_link_put(rlink);
172	if (cache)
173		nl_cache_free(cache);
174	if (handle)
175		nl_socket_free(handle);
176	return ret;
177}
178