vlan_netlink.c

  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_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
138static 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
201static 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
210static 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
221static 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
279nla_put_failure:
280	return -EMSGSIZE;
281}
282
283static 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
290struct 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
305int __init vlan_netlink_init(void)
306{
307	return rtnl_link_register(&vlan_link_ops);
308}
309
310void __exit vlan_netlink_fini(void)
311{
312	rtnl_link_unregister(&vlan_link_ops);
313}
314
315MODULE_ALIAS_RTNL_LINK("vlan");