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
18static 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
26static 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
31static 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
39static 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
104static 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(attr, data[IFLA_VLAN_INGRESS_QOS], rem) {
121			if (nla_type(attr) != IFLA_VLAN_QOS_MAPPING)
122				continue;
123			m = nla_data(attr);
124			vlan_dev_set_ingress_priority(dev, m->to, m->from);
125		}
126	}
127	if (data[IFLA_VLAN_EGRESS_QOS]) {
128		nla_for_each_nested(attr, data[IFLA_VLAN_EGRESS_QOS], rem) {
129			if (nla_type(attr) != IFLA_VLAN_QOS_MAPPING)
130				continue;
131			m = nla_data(attr);
132			err = vlan_dev_set_egress_priority(dev, m->from, m->to);
133			if (err)
134				return err;
135		}
136	}
137	return 0;
138}
139
140static int vlan_newlink(struct net *src_net, struct net_device *dev,
141			struct nlattr *tb[], struct nlattr *data[],
142			struct netlink_ext_ack *extack)
143{
144	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
145	struct net_device *real_dev;
146	unsigned int max_mtu;
147	__be16 proto;
148	int err;
149
150	if (!data[IFLA_VLAN_ID]) {
151		NL_SET_ERR_MSG_MOD(extack, "VLAN id not specified");
152		return -EINVAL;
153	}
154
155	if (!tb[IFLA_LINK]) {
156		NL_SET_ERR_MSG_MOD(extack, "link not specified");
157		return -EINVAL;
158	}
159
160	real_dev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
161	if (!real_dev) {
162		NL_SET_ERR_MSG_MOD(extack, "link does not exist");
163		return -ENODEV;
164	}
165
166	if (data[IFLA_VLAN_PROTOCOL])
167		proto = nla_get_be16(data[IFLA_VLAN_PROTOCOL]);
168	else
169		proto = htons(ETH_P_8021Q);
170
171	vlan->vlan_proto = proto;
172	vlan->vlan_id	 = nla_get_u16(data[IFLA_VLAN_ID]);
173	vlan->real_dev	 = real_dev;
174	dev->priv_flags |= (real_dev->priv_flags & IFF_XMIT_DST_RELEASE);
175	vlan->flags	 = VLAN_FLAG_REORDER_HDR;
176
177	err = vlan_check_real_dev(real_dev, vlan->vlan_proto, vlan->vlan_id,
178				  extack);
179	if (err < 0)
180		return err;
181
182	max_mtu = netif_reduces_vlan_mtu(real_dev) ? real_dev->mtu - VLAN_HLEN :
183						     real_dev->mtu;
184	if (!tb[IFLA_MTU])
185		dev->mtu = max_mtu;
186	else if (dev->mtu > max_mtu)
187		return -EINVAL;
188
189	/* Note: If this initial vlan_changelink() fails, we need
190	 * to call vlan_dev_free_egress_priority() to free memory.
191	 */
192	err = vlan_changelink(dev, tb, data, extack);
193
194	if (!err)
195		err = register_vlan_dev(dev, extack);
196
197	if (err)
198		vlan_dev_free_egress_priority(dev);
199	return err;
200}
201
202static inline size_t vlan_qos_map_size(unsigned int n)
203{
204	if (n == 0)
205		return 0;
206	/* IFLA_VLAN_{EGRESS,INGRESS}_QOS + n * IFLA_VLAN_QOS_MAPPING */
207	return nla_total_size(sizeof(struct nlattr)) +
208	       nla_total_size(sizeof(struct ifla_vlan_qos_mapping)) * n;
209}
210
211static size_t vlan_get_size(const struct net_device *dev)
212{
213	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
214
215	return nla_total_size(2) +	/* IFLA_VLAN_PROTOCOL */
216	       nla_total_size(2) +	/* IFLA_VLAN_ID */
217	       nla_total_size(sizeof(struct ifla_vlan_flags)) + /* IFLA_VLAN_FLAGS */
218	       vlan_qos_map_size(vlan->nr_ingress_mappings) +
219	       vlan_qos_map_size(vlan->nr_egress_mappings);
220}
221
222static int vlan_fill_info(struct sk_buff *skb, const struct net_device *dev)
223{
224	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
225	struct vlan_priority_tci_mapping *pm;
226	struct ifla_vlan_flags f;
227	struct ifla_vlan_qos_mapping m;
228	struct nlattr *nest;
229	unsigned int i;
230
231	if (nla_put_be16(skb, IFLA_VLAN_PROTOCOL, vlan->vlan_proto) ||
232	    nla_put_u16(skb, IFLA_VLAN_ID, vlan->vlan_id))
233		goto nla_put_failure;
234	if (vlan->flags) {
235		f.flags = vlan->flags;
236		f.mask  = ~0;
237		if (nla_put(skb, IFLA_VLAN_FLAGS, sizeof(f), &f))
238			goto nla_put_failure;
239	}
240	if (vlan->nr_ingress_mappings) {
241		nest = nla_nest_start_noflag(skb, IFLA_VLAN_INGRESS_QOS);
242		if (nest == NULL)
243			goto nla_put_failure;
244
245		for (i = 0; i < ARRAY_SIZE(vlan->ingress_priority_map); i++) {
246			if (!vlan->ingress_priority_map[i])
247				continue;
248
249			m.from = i;
250			m.to   = vlan->ingress_priority_map[i];
251			if (nla_put(skb, IFLA_VLAN_QOS_MAPPING,
252				    sizeof(m), &m))
253				goto nla_put_failure;
254		}
255		nla_nest_end(skb, nest);
256	}
257
258	if (vlan->nr_egress_mappings) {
259		nest = nla_nest_start_noflag(skb, IFLA_VLAN_EGRESS_QOS);
260		if (nest == NULL)
261			goto nla_put_failure;
262
263		for (i = 0; i < ARRAY_SIZE(vlan->egress_priority_map); i++) {
264			for (pm = vlan->egress_priority_map[i]; pm;
265			     pm = pm->next) {
266				if (!pm->vlan_qos)
267					continue;
268
269				m.from = pm->priority;
270				m.to   = (pm->vlan_qos >> 13) & 0x7;
271				if (nla_put(skb, IFLA_VLAN_QOS_MAPPING,
272					    sizeof(m), &m))
273					goto nla_put_failure;
274			}
275		}
276		nla_nest_end(skb, nest);
277	}
278	return 0;
279
280nla_put_failure:
281	return -EMSGSIZE;
282}
283
284static struct net *vlan_get_link_net(const struct net_device *dev)
285{
286	struct net_device *real_dev = vlan_dev_priv(dev)->real_dev;
287
288	return dev_net(real_dev);
289}
290
291struct rtnl_link_ops vlan_link_ops __read_mostly = {
292	.kind		= "vlan",
293	.maxtype	= IFLA_VLAN_MAX,
294	.policy		= vlan_policy,
295	.priv_size	= sizeof(struct vlan_dev_priv),
296	.setup		= vlan_setup,
297	.validate	= vlan_validate,
298	.newlink	= vlan_newlink,
299	.changelink	= vlan_changelink,
300	.dellink	= unregister_vlan_dev,
301	.get_size	= vlan_get_size,
302	.fill_info	= vlan_fill_info,
303	.get_link_net	= vlan_get_link_net,
304};
305
306int __init vlan_netlink_init(void)
307{
308	return rtnl_link_register(&vlan_link_ops);
309}
310
311void __exit vlan_netlink_fini(void)
312{
313	rtnl_link_unregister(&vlan_link_ops);
314}
315
316MODULE_ALIAS_RTNL_LINK("vlan");
317