xref: /freebsd/contrib/wpa/src/ap/vlan_util.c (revision 640235e2c2ba32947f7c59d168437ffa1280f1e6)
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 */
32 int vlan_add(const char *if_name, int vid, const char *vlan_if_name)
33 {
34 	int err, 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 	err = nl_connect(handle, NETLINK_ROUTE);
62 	if (err < 0) {
63 		wpa_printf(MSG_ERROR, "VLAN: failed to connect to netlink: %s",
64 			   nl_geterror(err));
65 		goto vlan_add_error;
66 	}
67 
68 	err = rtnl_link_alloc_cache(handle, AF_UNSPEC, &cache);
69 	if (err < 0) {
70 		cache = NULL;
71 		wpa_printf(MSG_ERROR, "VLAN: failed to alloc cache: %s",
72 			   nl_geterror(err));
73 		goto vlan_add_error;
74 	}
75 
76 	if (!(if_idx = rtnl_link_name2i(cache, if_name))) {
77 		/* link does not exist */
78 		wpa_printf(MSG_ERROR, "VLAN: interface %s does not exist",
79 			   if_name);
80 		goto vlan_add_error;
81 	}
82 
83 	if ((rlink = rtnl_link_get_by_name(cache, vlan_if_name))) {
84 		/* link does exist */
85 		rtnl_link_put(rlink);
86 		rlink = NULL;
87 		wpa_printf(MSG_ERROR, "VLAN: interface %s already exists",
88 			   vlan_if_name);
89 		ret = 1;
90 		goto vlan_add_error;
91 	}
92 
93 	rlink = rtnl_link_alloc();
94 	if (!rlink) {
95 		wpa_printf(MSG_ERROR, "VLAN: failed to allocate new link");
96 		goto vlan_add_error;
97 	}
98 
99 	err = rtnl_link_set_type(rlink, "vlan");
100 	if (err < 0) {
101 		wpa_printf(MSG_ERROR, "VLAN: failed to set link type: %s",
102 			   nl_geterror(err));
103 		goto vlan_add_error;
104 	}
105 
106 	rtnl_link_set_link(rlink, if_idx);
107 	rtnl_link_set_name(rlink, vlan_if_name);
108 
109 	err = rtnl_link_vlan_set_id(rlink, vid);
110 	if (err < 0) {
111 		wpa_printf(MSG_ERROR, "VLAN: failed to set link vlan id: %s",
112 			   nl_geterror(err));
113 		goto vlan_add_error;
114 	}
115 
116 	err = rtnl_link_add(handle, rlink, NLM_F_CREATE);
117 	if (err < 0) {
118 		wpa_printf(MSG_ERROR, "VLAN: failed to create link %s for "
119 			   "vlan %d on %s (%d): %s",
120 			   vlan_if_name, vid, if_name, if_idx,
121 			   nl_geterror(err));
122 		goto vlan_add_error;
123 	}
124 
125 	ret = 0;
126 
127 vlan_add_error:
128 	if (rlink)
129 		rtnl_link_put(rlink);
130 	if (cache)
131 		nl_cache_free(cache);
132 	if (handle)
133 		nl_socket_free(handle);
134 	return ret;
135 }
136 
137 
138 int vlan_rem(const char *if_name)
139 {
140 	int err, ret = -1;
141 	struct nl_sock *handle = NULL;
142 	struct nl_cache *cache = NULL;
143 	struct rtnl_link *rlink = NULL;
144 
145 	wpa_printf(MSG_DEBUG, "VLAN: vlan_rem(if_name=%s)", if_name);
146 
147 	handle = nl_socket_alloc();
148 	if (!handle) {
149 		wpa_printf(MSG_ERROR, "VLAN: failed to open netlink socket");
150 		goto vlan_rem_error;
151 	}
152 
153 	err = nl_connect(handle, NETLINK_ROUTE);
154 	if (err < 0) {
155 		wpa_printf(MSG_ERROR, "VLAN: failed to connect to netlink: %s",
156 			   nl_geterror(err));
157 		goto vlan_rem_error;
158 	}
159 
160 	err = rtnl_link_alloc_cache(handle, AF_UNSPEC, &cache);
161 	if (err < 0) {
162 		cache = NULL;
163 		wpa_printf(MSG_ERROR, "VLAN: failed to alloc cache: %s",
164 			   nl_geterror(err));
165 		goto vlan_rem_error;
166 	}
167 
168 	if (!(rlink = rtnl_link_get_by_name(cache, if_name))) {
169 		/* link does not exist */
170 		wpa_printf(MSG_ERROR, "VLAN: interface %s does not exists",
171 			   if_name);
172 		goto vlan_rem_error;
173 	}
174 
175 	err = rtnl_link_delete(handle, rlink);
176 	if (err < 0) {
177 		wpa_printf(MSG_ERROR, "VLAN: failed to remove link %s: %s",
178 			   if_name, nl_geterror(err));
179 		goto vlan_rem_error;
180 	}
181 
182 	ret = 0;
183 
184 vlan_rem_error:
185 	if (rlink)
186 		rtnl_link_put(rlink);
187 	if (cache)
188 		nl_cache_free(cache);
189 	if (handle)
190 		nl_socket_free(handle);
191 	return ret;
192 }
193