aboutsummaryrefslogtreecommitdiff
path: root/net/bridge/br_netlink.c
blob: ce902bf8a61803782b6cea8c9f654eb978e25a24 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
/*
 *	Bridge netlink control interface
 *
 *	Authors:
 *	Stephen Hemminger		<shemminger@osdl.org>
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License
 *	as published by the Free Software Foundation; either version
 *	2 of the License, or (at your option) any later version.
 */

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/etherdevice.h>
#include <net/rtnetlink.h>
#include <net/net_namespace.h>
#include <net/sock.h>
#include <uapi/linux/if_bridge.h>

#include "br_private.h"
#include "br_private_stp.h"

static inline size_t br_port_info_size(void)
{
	return nla_total_size(1)	/* IFLA_BRPORT_STATE  */
		+ nla_total_size(2)	/* IFLA_BRPORT_PRIORITY */
		+ nla_total_size(4)	/* IFLA_BRPORT_COST */
		+ nla_total_size(1)	/* IFLA_BRPORT_MODE */
		+ nla_total_size(1)	/* IFLA_BRPORT_GUARD */
		+ nla_total_size(1)	/* IFLA_BRPORT_PROTECT */
		+ nla_total_size(1)	/* IFLA_BRPORT_FAST_LEAVE */
		+ nla_total_size(1)	/* IFLA_BRPORT_LEARNING */
		+ 0;
}

static inline size_t br_nlmsg_size(void)
{
	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
		+ nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
		+ nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
		+ nla_total_size(4) /* IFLA_MASTER */
		+ nla_total_size(4) /* IFLA_MTU */
		+ nla_total_size(4) /* IFLA_LINK */
		+ nla_total_size(1) /* IFLA_OPERSTATE */
		+ nla_total_size(br_port_info_size()); /* IFLA_PROTINFO */
}

static int br_port_fill_attrs(struct sk_buff *skb,
			      const struct net_bridge_port *p)
{
	u8 mode = !!(p->flags & BR_HAIRPIN_MODE);

	if (nla_put_u8(skb, IFLA_BRPORT_STATE, p->state) ||
	    nla_put_u16(skb, IFLA_BRPORT_PRIORITY, p->priority) ||
	    nla_put_u32(skb, IFLA_BRPORT_COST, p->path_cost) ||
	    nla_put_u8(skb, IFLA_BRPORT_MODE, mode) ||
	    nla_put_u8(skb, IFLA_BRPORT_GUARD, !!(p->flags & BR_BPDU_GUARD)) ||
	    nla_put_u8(skb, IFLA_BRPORT_PROTECT, !!(p->flags & BR_ROOT_BLOCK)) ||
	    nla_put_u8(skb, IFLA_BRPORT_FAST_LEAVE, !!(p->flags & BR_MULTICAST_FAST_LEAVE)) ||
	    nla_put_u8(skb, IFLA_BRPORT_LEARNING, !!(p->flags & BR_LEARNING)))
		return -EMSGSIZE;

	return 0;
}

/*
 * Create one netlink message for one interface
 * Contains port and master info as well as carrier and bridge state.
 */
static int br_fill_ifinfo(struct sk_buff *skb,
			  const struct net_bridge_port *port,
			  u32 pid, u32 seq, int event, unsigned int flags,
			  u32 filter_mask, const struct net_device *dev)
{
	const struct net_bridge *br;
	struct ifinfomsg *hdr;
	struct nlmsghdr *nlh;
	u8 operstate = netif_running(dev) ? dev->operstate : IF_OPER_DOWN;

	if (port)
		br = port->br;
	else
		br = netdev_priv(dev);

	br_debug(br, "br_fill_info event %d port %s master %s\n",
		     event, dev->name, br->dev->name);

	nlh = nlmsg_put(skb, pid, seq, event, sizeof(*hdr), flags);
	if (nlh == NULL)
		return -EMSGSIZE;

	hdr = nlmsg_data(nlh);
	hdr->ifi_family = AF_BRIDGE;
	hdr->__ifi_pad = 0;
	hdr->ifi_type = dev->type;
	hdr->ifi_index = dev->ifindex;
	hdr->ifi_flags = dev_get_flags(dev);
	hdr->ifi_change = 0;

	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
	    nla_put_u32(skb, IFLA_MASTER, br->dev->ifindex) ||
	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
	    nla_put_u8(skb, IFLA_OPERSTATE, operstate) ||
	    (dev->addr_len &&
	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
	    (dev->ifindex != dev->iflink &&
	     nla_put_u32(skb, IFLA_LINK, dev->iflink)))
		goto nla_put_failure;

	if (event == RTM_NEWLINK && port) {
		struct nlattr *nest
			= nla_nest_start(skb, IFLA_PROTINFO | NLA_F_NESTED);

		if (nest == NULL || br_port_fill_attrs(skb, port) < 0)
			goto nla_put_failure;
		nla_nest_end(skb, nest);
	}

	/* Check if  the VID information is requested */
	if (filter_mask & RTEXT_FILTER_BRVLAN) {
		struct nlattr *af;
		const struct net_port_vlans *pv;
		struct bridge_vlan_info vinfo;
		u16 vid;
		u16 pvid;

		if (port)
			pv = nbp_get_vlan_info(port);
		else
			pv = br_get_vlan_info(br);

		if (!pv || bitmap_empty(pv->vlan_bitmap, BR_VLAN_BITMAP_LEN))
			goto done;

		af = nla_nest_start(skb, IFLA_AF_SPEC);
		if (!af)
			goto nla_put_failure;

		pvid = br_get_pvid(pv);
		for_each_set_bit(vid, pv->vlan_bitmap, BR_VLAN_BITMAP_LEN) {
			vinfo.vid = vid;
			vinfo.flags = 0;
			if (vid == pvid)
				vinfo.flags |= BRIDGE_VLAN_INFO_PVID;

			if (test_bit(vid, pv->untagged_bitmap))
				vinfo.flags |= BRIDGE_VLAN_INFO_UNTAGGED;

			if (nla_put(skb, IFLA_BRIDGE_VLAN_INFO,
				    sizeof(vinfo), &vinfo))
				goto nla_put_failure;
		}

		nla_nest_end(skb, af);
	}

done:
	return nlmsg_end(skb, nlh);

nla_put_failure:
	nlmsg_cancel(skb, nlh);
	return -EMSGSIZE;
}

/*
 * Notify listeners of a change in port information
 */
void br_ifinfo_notify(int event, struct net_bridge_port *port)
{
	struct net *net;
	struct sk_buff *skb;
	int err = -ENOBUFS;

	if (!port)
		return;

	net = dev_net(port->dev);
	br_debug(port->br, "port %u(%s) event %d\n",
		 (unsigned int)port->port_no, port->dev->name, event);

	skb = nlmsg_new(br_nlmsg_size(), GFP_ATOMIC);
	if (skb == NULL)
		goto errout;

	err = br_fill_ifinfo(skb, port, 0, 0, event, 0, 0, port->dev);
	if (err < 0) {
		/* -EMSGSIZE implies BUG in br_nlmsg_size() */
		WARN_ON(err == -EMSGSIZE);
		kfree_skb(skb);
		goto errout;
	}
	rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL, GFP_ATOMIC);
	return;
errout:
	if (err < 0)
		rtnl_set_sk_err(net, RTNLGRP_LINK, err);
}


/*
 * Dump information about all ports, in response to GETLINK
 */
int br_getlink(struct sk_buff *skb, u32 pid, u32 seq,
	       struct net_device *dev, u32 filter_mask)
{
	int err = 0;
	struct net_bridge_port *port = br_port_get_rcu(dev);

	/* not a bridge port and  */
	if (!port && !(filter_mask & RTEXT_FILTER_BRVLAN))
		goto out;

	err = br_fill_ifinfo(skb, port, pid, seq, RTM_NEWLINK, NLM_F_MULTI,
			     filter_mask, dev);
out:
	return err;
}

static const struct nla_policy ifla_br_policy[IFLA_MAX+1] = {
	[IFLA_BRIDGE_FLAGS]	= { .type = NLA_U16 },
	[IFLA_BRIDGE_MODE]	= { .type = NLA_U16 },
	[IFLA_BRIDGE_VLAN_INFO]	= { .type = NLA_BINARY,
				    .len = sizeof(struct bridge_vlan_info), },
};

static int br_afspec(struct net_bridge *br,
		     struct net_bridge_port *p,
		     struct nlattr *af_spec,
		     int cmd)
{
	struct nlattr *tb[IFLA_BRIDGE_MAX+1];
	int err = 0;

	err = nla_parse_nested(tb, IFLA_BRIDGE_MAX, af_spec, ifla_br_policy);
	if (err)
		return err;

	if (tb[IFLA_BRIDGE_VLAN_INFO]) {
		struct bridge_vlan_info *vinfo;

		vinfo = nla_data(tb[IFLA_BRIDGE_VLAN_INFO]);

		if (vinfo->vid >= VLAN_N_VID)
			return -EINVAL;

		switch (cmd) {
		case RTM_SETLINK:
			if (p) {
				err = nbp_vlan_add(p, vinfo->vid, vinfo->flags);
				if (err)
					break;

				if (vinfo->flags & BRIDGE_VLAN_INFO_MASTER)
					err = br_vlan_add(p->br, vinfo->vid,
							  vinfo->flags);
			} else
				err = br_vlan_add(br, vinfo->vid, vinfo->flags);

			if (err)
				break;

			break;

		case RTM_DELLINK:
			if (p) {
				nbp_vlan_delete(p, vinfo->vid);
				if (vinfo->flags & BRIDGE_VLAN_INFO_MASTER)
					br_vlan_delete(p->br, vinfo->vid);
			} else
				br_vlan_delete(br, vinfo->vid);
			break;
		}
	}

	return err;
}

static const struct nla_policy ifla_brport_policy[IFLA_BRPORT_MAX + 1] = {
	[IFLA_BRPORT_STATE]	= { .type = NLA_U8 },
	[IFLA_BRPORT_COST]	= { .type = NLA_U32 },
	[IFLA_BRPORT_PRIORITY]	= { .type = NLA_U16 },
	[IFLA_BRPORT_MODE]	= { .type = NLA_U8 },
	[IFLA_BRPORT_GUARD]	= { .type = NLA_U8 },
	[IFLA_BRPORT_PROTECT]	= { .type = NLA_U8 },
	[IFLA_BRPORT_LEARNING]	= { .type = NLA_U8 },
};

/* Change the state of the port and notify spanning tree */
static int br_set_port_state(struct net_bridge_port *p, u8 state)
{
	if (state > BR_STATE_BLOCKING)
		return -EINVAL;

	/* if kernel STP is running, don't allow changes */
	if (p->br->stp_enabled == BR_KERNEL_STP)
		return -EBUSY;

	/* if device is not up, change is not allowed
	 * if link is not present, only allowable state is disabled
	 */
	if (!netif_running(p->dev) ||
	    (!netif_oper_up(p->dev) && state != BR_STATE_DISABLED))
		return -ENETDOWN;

	p->state = state;
	br_log_state(p);
	br_port_state_selection(p->br);
	return 0;
}

/* Set/clear or port flags based on attribute */
static void br_set_port_flag(struct net_bridge_port *p, struct nlattr *tb[],
			   int attrtype, unsigned long mask)
{
	if (tb[attrtype]) {
		u8 flag = nla_get_u8(tb[attrtype]);
		if (flag)
			p->flags |= mask;
		else
			p->flags &= ~mask;
	}
}

/* Process bridge protocol info on port */
static int br_setport(struct net_bridge_port *p, struct nlattr *tb[])
{
	int err;

	br_set_port_flag(p, tb, IFLA_BRPORT_MODE, BR_HAIRPIN_MODE);
	br_set_port_flag(p, tb, IFLA_BRPORT_GUARD, BR_BPDU_GUARD);
	br_set_port_flag(p, tb, IFLA_BRPORT_FAST_LEAVE, BR_MULTICAST_FAST_LEAVE);
	br_set_port_flag(p, tb, IFLA_BRPORT_PROTECT, BR_ROOT_BLOCK);
	br_set_port_flag(p, tb, IFLA_BRPORT_LEARNING, BR_LEARNING);

	if (tb[IFLA_BRPORT_COST]) {
		err = br_stp_set_path_cost(p, nla_get_u32(tb[IFLA_BRPORT_COST]));
		if (err)
			return err;
	}

	if (tb[IFLA_BRPORT_PRIORITY]) {
		err = br_stp_set_port_priority(p, nla_get_u16(tb[IFLA_BRPORT_PRIORITY]));
		if (err)
			return err;
	}

	if (tb[IFLA_BRPORT_STATE]) {
		err = br_set_port_state(p, nla_get_u8(tb[IFLA_BRPORT_STATE]));
		if (err)
			return err;
	}
	return 0;
}

/* Change state and parameters on port. */
int br_setlink(struct net_device *dev, struct nlmsghdr *nlh)
{
	struct nlattr *protinfo;
	struct nlattr *afspec;
	struct net_bridge_port *p;
	struct nlattr *tb[IFLA_BRPORT_MAX + 1];
	int err = 0;

	protinfo = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg), IFLA_PROTINFO);
	afspec = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg), IFLA_AF_SPEC);
	if (!protinfo && !afspec)
		return 0;

	p = br_port_get_rtnl(dev);
	/* We want to accept dev as bridge itself if the AF_SPEC
	 * is set to see if someone is setting vlan info on the brigde
	 */
	if (!p && !afspec)
		return -EINVAL;

	if (p && protinfo) {
		if (protinfo->nla_type & NLA_F_NESTED) {
			err = nla_parse_nested(tb, IFLA_BRPORT_MAX,
					       protinfo, ifla_brport_policy);
			if (err)
				return err;

			spin_lock_bh(&p->br->lock);
			err = br_setport(p, tb);
			spin_unlock_bh(&p->br->lock);
		} else {
			/* Binary compatability with old RSTP */
			if (nla_len(protinfo) < sizeof(u8))
				return -EINVAL;

			spin_lock_bh(&p->br->lock);
			err = br_set_port_state(p, nla_get_u8(protinfo));
			spin_unlock_bh(&p->br->lock);
		}
		if (err)
			goto out;
	}

	if (afspec) {
		err = br_afspec((struct net_bridge *)netdev_priv(dev), p,
				afspec, RTM_SETLINK);
	}

	if (err == 0)
		br_ifinfo_notify(RTM_NEWLINK, p);

out:
	return err;
}

/* Delete port information */
int br_dellink(struct net_device *dev, struct nlmsghdr *nlh)
{
	struct nlattr *afspec;
	struct net_bridge_port *p;
	int err;

	afspec = nlmsg_find_attr(nlh, sizeof(struct ifinfomsg), IFLA_AF_SPEC);
	if (!afspec)
		return 0;

	p = br_port_get_rtnl(dev);
	/* We want to accept dev as bridge itself as well */
	if (!p && !(dev->priv_flags & IFF_EBRIDGE))
		return -EINVAL;

	err = br_afspec((struct net_bridge *)netdev_priv(dev), p,
			afspec, RTM_DELLINK);

	return err;
}
static int br_validate(struct nlattr *tb[], struct nlattr *data[])
{
	if (tb[IFLA_ADDRESS]) {
		if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
			return -EINVAL;
		if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
			return -EADDRNOTAVAIL;
	}

	return 0;
}

static size_t br_get_link_af_size(const struct net_device *dev)
{
	struct net_port_vlans *pv;

	if (br_port_exists(dev))
		pv = nbp_get_vlan_info(br_port_get_rcu(dev));
	else if (dev->priv_flags & IFF_EBRIDGE)
		pv = br_get_vlan_info((struct net_bridge *)netdev_priv(dev));
	else
		return 0;

	if (!pv)
		return 0;

	/* Each VLAN is returned in bridge_vlan_info along with flags */
	return pv->num_vlans * nla_total_size(sizeof(struct bridge_vlan_info));
}

static struct rtnl_af_ops br_af_ops = {
	.family			= AF_BRIDGE,
	.get_link_af_size	= br_get_link_af_size,
};

struct rtnl_link_ops br_link_ops __read_mostly = {
	.kind		= "bridge",
	.priv_size	= sizeof(struct net_bridge),
	.setup		= br_dev_setup,
	.validate	= br_validate,
	.dellink	= br_dev_delete,
};

int __init br_netlink_init(void)
{
	int err;

	br_mdb_init();
	err = rtnl_af_register(&br_af_ops);
	if (err)
		goto out;

	err = rtnl_link_register(&br_link_ops);
	if (err)
		goto out_af;

	return 0;

out_af:
	rtnl_af_unregister(&br_af_ops);
out:
	br_mdb_uninit();
	return err;
}

void __exit br_netlink_fini(void)
{
	br_mdb_uninit();
	rtnl_af_unregister(&br_af_ops);
	rtnl_link_unregister(&br_link_ops);
}