1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *	VLAN netlink control interface
4  *
5  * 	Copyright (c) 2007 Patrick McHardy <kaber@trash.net>
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/netdevice.h>
10 #include <linux/if_vlan.h>
11 #include <linux/module.h>
12 #include <net/net_namespace.h>
13 #include <net/netlink.h>
14 #include <net/rtnetlink.h>
15 #include "vlan.h"
16 
17 
18 static const struct nla_policy vlan_policy[IFLA_VLAN_MAX + 1] = {
19 	[IFLA_VLAN_ID]		= { .type = NLA_U16 },
20 	[IFLA_VLAN_FLAGS]	= { .len = sizeof(struct ifla_vlan_flags) },
21 	[IFLA_VLAN_EGRESS_QOS]	= { .type = NLA_NESTED },
22 	[IFLA_VLAN_INGRESS_QOS] = { .type = NLA_NESTED },
23 	[IFLA_VLAN_PROTOCOL]	= { .type = NLA_U16 },
24 };
25 
26 static const struct nla_policy vlan_map_policy[IFLA_VLAN_QOS_MAX + 1] = {
27 	[IFLA_VLAN_QOS_MAPPING] = { .len = sizeof(struct ifla_vlan_qos_mapping) },
28 };
29 
30 
31 static inline int vlan_validate_qos_map(struct nlattr *attr)
32 {
33 	if (!attr)
34 		return 0;
35 	return nla_validate_nested_deprecated(attr, IFLA_VLAN_QOS_MAX,
36 					      vlan_map_policy, NULL);
37 }
38 
39 static int vlan_validate(struct nlattr *tb[], struct nlattr *data[],
40 			 struct netlink_ext_ack *extack)
41 {
42 	struct ifla_vlan_flags *flags;
43 	u16 id;
44 	int err;
45 
46 	if (tb[IFLA_ADDRESS]) {
47 		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) {
48 			NL_SET_ERR_MSG_MOD(extack, "Invalid link address");
49 			return -EINVAL;
50 		}
51 		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) {
52 			NL_SET_ERR_MSG_MOD(extack, "Invalid link address");
53 			return -EADDRNOTAVAIL;
54 		}
55 	}
56 
57 	if (!data) {
58 		NL_SET_ERR_MSG_MOD(extack, "VLAN properties not specified");
59 		return -EINVAL;
60 	}
61 
62 	if (data[IFLA_VLAN_PROTOCOL]) {
63 		switch (nla_get_be16(data[IFLA_VLAN_PROTOCOL])) {
64 		case htons(ETH_P_8021Q):
65 		case htons(ETH_P_8021AD):
66 			break;
67 		default:
68 			NL_SET_ERR_MSG_MOD(extack, "Invalid VLAN protocol");
69 			return -EPROTONOSUPPORT;
70 		}
71 	}
72 
73 	if (data[IFLA_VLAN_ID]) {
74 		id = nla_get_u16(data[IFLA_VLAN_ID]);
75 		if (id >= VLAN_VID_MASK) {
76 			NL_SET_ERR_MSG_MOD(extack, "Invalid VLAN id");
77 			return -ERANGE;
78 		}
79 	}
80 	if (data[IFLA_VLAN_FLAGS]) {
81 		flags = nla_data(data[IFLA_VLAN_FLAGS]);
82 		if ((flags->flags & flags->mask) &
83 		    ~(VLAN_FLAG_REORDER_HDR | VLAN_FLAG_GVRP |
84 		      VLAN_FLAG_LOOSE_BINDING | VLAN_FLAG_MVRP |
85 		      VLAN_FLAG_BRIDGE_BINDING)) {
86 			NL_SET_ERR_MSG_MOD(extack, "Invalid VLAN flags");
87 			return -EINVAL;
88 		}
89 	}
90 
91 	err = vlan_validate_qos_map(data[IFLA_VLAN_INGRESS_QOS]);
92 	if (err < 0) {
93 		NL_SET_ERR_MSG_MOD(extack, "Invalid ingress QOS map");
94 		return err;
95 	}
96 	err = vlan_validate_qos_map(data[IFLA_VLAN_EGRESS_QOS]);
97 	if (err < 0) {
98 		NL_SET_ERR_MSG_MOD(extack, "Invalid egress QOS map");
99 		return err;
100 	}
101 	return 0;
102 }
103 
104 static int vlan_changelink(struct net_device *dev, struct nlattr *tb[],
105 			   struct nlattr *data[],
106 			   struct netlink_ext_ack *extack)
107 {
108 	struct ifla_vlan_flags *flags;
109 	struct ifla_vlan_qos_mapping *m;
110 	struct nlattr *attr;
111 	int rem, err;
112 
113 	if (data[IFLA_VLAN_FLAGS]) {
114 		flags = nla_data(data[IFLA_VLAN_FLAGS]);
115 		err = vlan_dev_change_flags(dev, flags->flags, flags->mask);
116 		if (err)
117 			return err;
118 	}
119 	if (data[IFLA_VLAN_INGRESS_QOS]) {
120 		nla_for_each_nested_type(attr, IFLA_VLAN_QOS_MAPPING,
121 					 data[IFLA_VLAN_INGRESS_QOS], rem) {
122 			m = nla_data(attr);
123 			vlan_dev_set_ingress_priority(dev, m->to, m->from);
124 		}
125 	}
126 	if (data[IFLA_VLAN_EGRESS_QOS]) {
127 		nla_for_each_nested_type(attr, IFLA_VLAN_QOS_MAPPING,
128 					 data[IFLA_VLAN_EGRESS_QOS], rem) {
129 			m = nla_data(attr);
130 			err = vlan_dev_set_egress_priority(dev, m->from, m->to);
131 			if (err)
132 				return err;
133 		}
134 	}
135 	return 0;
136 }
137 
138 static int vlan_newlink(struct net_device *dev,
139 			struct rtnl_newlink_params *params,
140 			struct netlink_ext_ack *extack)
141 {
142 	struct net *link_net = rtnl_newlink_link_net(params);
143 	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
144 	struct nlattr **data = params->data;
145 	struct nlattr **tb = params->tb;
146 	struct net_device *real_dev;
147 	unsigned int max_mtu;
148 	__be16 proto;
149 	int err;
150 
151 	if (!data[IFLA_VLAN_ID]) {
152 		NL_SET_ERR_MSG_MOD(extack, "VLAN id not specified");
153 		return -EINVAL;
154 	}
155 
156 	if (!tb[IFLA_LINK]) {
157 		NL_SET_ERR_MSG_MOD(extack, "link not specified");
158 		return -EINVAL;
159 	}
160 
161 	real_dev = __dev_get_by_index(link_net, nla_get_u32(tb[IFLA_LINK]));
162 	if (!real_dev) {
163 		NL_SET_ERR_MSG_MOD(extack, "link does not exist");
164 		return -ENODEV;
165 	}
166 
167 	proto = nla_get_be16_default(data[IFLA_VLAN_PROTOCOL],
168 				     htons(ETH_P_8021Q));
169 
170 	vlan->vlan_proto = proto;
171 	vlan->vlan_id	 = nla_get_u16(data[IFLA_VLAN_ID]);
172 	vlan->real_dev	 = real_dev;
173 	dev->priv_flags |= (real_dev->priv_flags & IFF_XMIT_DST_RELEASE);
174 	vlan->flags	 = VLAN_FLAG_REORDER_HDR;
175 
176 	err = vlan_check_real_dev(real_dev, vlan->vlan_proto, vlan->vlan_id,
177 				  extack);
178 	if (err < 0)
179 		return err;
180 
181 	max_mtu = netif_reduces_vlan_mtu(real_dev) ? real_dev->mtu - VLAN_HLEN :
182 						     real_dev->mtu;
183 	if (!tb[IFLA_MTU])
184 		dev->mtu = max_mtu;
185 	else if (dev->mtu > max_mtu)
186 		return -EINVAL;
187 
188 	/* Note: If this initial vlan_changelink() fails, we need
189 	 * to call vlan_dev_free_egress_priority() to free memory.
190 	 */
191 	err = vlan_changelink(dev, tb, data, extack);
192 
193 	if (!err)
194 		err = register_vlan_dev(dev, extack);
195 
196 	if (err)
197 		vlan_dev_free_egress_priority(dev);
198 	return err;
199 }
200 
201 static inline size_t vlan_qos_map_size(unsigned int n)
202 {
203 	if (n == 0)
204 		return 0;
205 	/* IFLA_VLAN_{EGRESS,INGRESS}_QOS + n * IFLA_VLAN_QOS_MAPPING */
206 	return nla_total_size(sizeof(struct nlattr)) +
207 	       nla_total_size(sizeof(struct ifla_vlan_qos_mapping)) * n;
208 }
209 
210 static size_t vlan_get_size(const struct net_device *dev)
211 {
212 	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
213 
214 	return nla_total_size(2) +	/* IFLA_VLAN_PROTOCOL */
215 	       nla_total_size(2) +	/* IFLA_VLAN_ID */
216 	       nla_total_size(sizeof(struct ifla_vlan_flags)) + /* IFLA_VLAN_FLAGS */
217 	       vlan_qos_map_size(vlan->nr_ingress_mappings) +
218 	       vlan_qos_map_size(vlan->nr_egress_mappings);
219 }
220 
221 static int vlan_fill_info(struct sk_buff *skb, const struct net_device *dev)
222 {
223 	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
224 	struct vlan_priority_tci_mapping *pm;
225 	struct ifla_vlan_flags f;
226 	struct ifla_vlan_qos_mapping m;
227 	struct nlattr *nest;
228 	unsigned int i;
229 
230 	if (nla_put_be16(skb, IFLA_VLAN_PROTOCOL, vlan->vlan_proto) ||
231 	    nla_put_u16(skb, IFLA_VLAN_ID, vlan->vlan_id))
232 		goto nla_put_failure;
233 	if (vlan->flags) {
234 		f.flags = vlan->flags;
235 		f.mask  = ~0;
236 		if (nla_put(skb, IFLA_VLAN_FLAGS, sizeof(f), &f))
237 			goto nla_put_failure;
238 	}
239 	if (vlan->nr_ingress_mappings) {
240 		nest = nla_nest_start_noflag(skb, IFLA_VLAN_INGRESS_QOS);
241 		if (nest == NULL)
242 			goto nla_put_failure;
243 
244 		for (i = 0; i < ARRAY_SIZE(vlan->ingress_priority_map); i++) {
245 			if (!vlan->ingress_priority_map[i])
246 				continue;
247 
248 			m.from = i;
249 			m.to   = vlan->ingress_priority_map[i];
250 			if (nla_put(skb, IFLA_VLAN_QOS_MAPPING,
251 				    sizeof(m), &m))
252 				goto nla_put_failure;
253 		}
254 		nla_nest_end(skb, nest);
255 	}
256 
257 	if (vlan->nr_egress_mappings) {
258 		nest = nla_nest_start_noflag(skb, IFLA_VLAN_EGRESS_QOS);
259 		if (nest == NULL)
260 			goto nla_put_failure;
261 
262 		for (i = 0; i < ARRAY_SIZE(vlan->egress_priority_map); i++) {
263 			for (pm = vlan->egress_priority_map[i]; pm;
264 			     pm = pm->next) {
265 				if (!pm->vlan_qos)
266 					continue;
267 
268 				m.from = pm->priority;
269 				m.to   = (pm->vlan_qos >> 13) & 0x7;
270 				if (nla_put(skb, IFLA_VLAN_QOS_MAPPING,
271 					    sizeof(m), &m))
272 					goto nla_put_failure;
273 			}
274 		}
275 		nla_nest_end(skb, nest);
276 	}
277 	return 0;
278 
279 nla_put_failure:
280 	return -EMSGSIZE;
281 }
282 
283 static struct net *vlan_get_link_net(const struct net_device *dev)
284 {
285 	struct net_device *real_dev = vlan_dev_priv(dev)->real_dev;
286 
287 	return dev_net(real_dev);
288 }
289 
290 struct rtnl_link_ops vlan_link_ops __read_mostly = {
291 	.kind		= "vlan",
292 	.maxtype	= IFLA_VLAN_MAX,
293 	.policy		= vlan_policy,
294 	.priv_size	= sizeof(struct vlan_dev_priv),
295 	.setup		= vlan_setup,
296 	.validate	= vlan_validate,
297 	.newlink	= vlan_newlink,
298 	.changelink	= vlan_changelink,
299 	.dellink	= unregister_vlan_dev,
300 	.get_size	= vlan_get_size,
301 	.fill_info	= vlan_fill_info,
302 	.get_link_net	= vlan_get_link_net,
303 };
304 
305 int __init vlan_netlink_init(void)
306 {
307 	return rtnl_link_register(&vlan_link_ops);
308 }
309 
310 void __exit vlan_netlink_fini(void)
311 {
312 	rtnl_link_unregister(&vlan_link_ops);
313 }
314 
315 MODULE_ALIAS_RTNL_LINK("vlan");
316