rtnetlink.c revision 1d00a4eb42bdade33a6ec0961cada93577a66ae6
1/*
2 * INET		An implementation of the TCP/IP protocol suite for the LINUX
3 *		operating system.  INET is implemented using the  BSD Socket
4 *		interface as the means of communication with the user level.
5 *
6 *		Routing netlink socket interface: protocol independent part.
7 *
8 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
9 *
10 *		This program is free software; you can redistribute it and/or
11 *		modify it under the terms of the GNU General Public License
12 *		as published by the Free Software Foundation; either version
13 *		2 of the License, or (at your option) any later version.
14 *
15 *	Fixes:
16 *	Vitaly E. Lavrov		RTA_OK arithmetics was wrong.
17 */
18
19#include <linux/errno.h>
20#include <linux/module.h>
21#include <linux/types.h>
22#include <linux/socket.h>
23#include <linux/kernel.h>
24#include <linux/timer.h>
25#include <linux/string.h>
26#include <linux/sockios.h>
27#include <linux/net.h>
28#include <linux/fcntl.h>
29#include <linux/mm.h>
30#include <linux/slab.h>
31#include <linux/interrupt.h>
32#include <linux/capability.h>
33#include <linux/skbuff.h>
34#include <linux/init.h>
35#include <linux/security.h>
36#include <linux/mutex.h>
37#include <linux/if_addr.h>
38
39#include <asm/uaccess.h>
40#include <asm/system.h>
41#include <asm/string.h>
42
43#include <linux/inet.h>
44#include <linux/netdevice.h>
45#include <net/ip.h>
46#include <net/protocol.h>
47#include <net/arp.h>
48#include <net/route.h>
49#include <net/udp.h>
50#include <net/sock.h>
51#include <net/pkt_sched.h>
52#include <net/fib_rules.h>
53#include <net/rtnetlink.h>
54#ifdef CONFIG_NET_WIRELESS_RTNETLINK
55#include <linux/wireless.h>
56#include <net/iw_handler.h>
57#endif	/* CONFIG_NET_WIRELESS_RTNETLINK */
58
59struct rtnl_link
60{
61	rtnl_doit_func		doit;
62	rtnl_dumpit_func	dumpit;
63};
64
65static DEFINE_MUTEX(rtnl_mutex);
66static struct sock *rtnl;
67
68void rtnl_lock(void)
69{
70	mutex_lock(&rtnl_mutex);
71}
72
73void __rtnl_unlock(void)
74{
75	mutex_unlock(&rtnl_mutex);
76}
77
78void rtnl_unlock(void)
79{
80	mutex_unlock(&rtnl_mutex);
81	if (rtnl && rtnl->sk_receive_queue.qlen)
82		rtnl->sk_data_ready(rtnl, 0);
83	netdev_run_todo();
84}
85
86int rtnl_trylock(void)
87{
88	return mutex_trylock(&rtnl_mutex);
89}
90
91int rtattr_parse(struct rtattr *tb[], int maxattr, struct rtattr *rta, int len)
92{
93	memset(tb, 0, sizeof(struct rtattr*)*maxattr);
94
95	while (RTA_OK(rta, len)) {
96		unsigned flavor = rta->rta_type;
97		if (flavor && flavor <= maxattr)
98			tb[flavor-1] = rta;
99		rta = RTA_NEXT(rta, len);
100	}
101	return 0;
102}
103
104struct rtnl_link *rtnl_msg_handlers[NPROTO];
105
106static inline int rtm_msgindex(int msgtype)
107{
108	int msgindex = msgtype - RTM_BASE;
109
110	/*
111	 * msgindex < 0 implies someone tried to register a netlink
112	 * control code. msgindex >= RTM_NR_MSGTYPES may indicate that
113	 * the message type has not been added to linux/rtnetlink.h
114	 */
115	BUG_ON(msgindex < 0 || msgindex >= RTM_NR_MSGTYPES);
116
117	return msgindex;
118}
119
120static rtnl_doit_func rtnl_get_doit(int protocol, int msgindex)
121{
122	struct rtnl_link *tab;
123
124	tab = rtnl_msg_handlers[protocol];
125	if (tab == NULL || tab[msgindex].doit == NULL)
126		tab = rtnl_msg_handlers[PF_UNSPEC];
127
128	return tab ? tab[msgindex].doit : NULL;
129}
130
131static rtnl_dumpit_func rtnl_get_dumpit(int protocol, int msgindex)
132{
133	struct rtnl_link *tab;
134
135	tab = rtnl_msg_handlers[protocol];
136	if (tab == NULL || tab[msgindex].dumpit == NULL)
137		tab = rtnl_msg_handlers[PF_UNSPEC];
138
139	return tab ? tab[msgindex].dumpit : NULL;
140}
141
142/**
143 * __rtnl_register - Register a rtnetlink message type
144 * @protocol: Protocol family or PF_UNSPEC
145 * @msgtype: rtnetlink message type
146 * @doit: Function pointer called for each request message
147 * @dumpit: Function pointer called for each dump request (NLM_F_DUMP) message
148 *
149 * Registers the specified function pointers (at least one of them has
150 * to be non-NULL) to be called whenever a request message for the
151 * specified protocol family and message type is received.
152 *
153 * The special protocol family PF_UNSPEC may be used to define fallback
154 * function pointers for the case when no entry for the specific protocol
155 * family exists.
156 *
157 * Returns 0 on success or a negative error code.
158 */
159int __rtnl_register(int protocol, int msgtype,
160		    rtnl_doit_func doit, rtnl_dumpit_func dumpit)
161{
162	struct rtnl_link *tab;
163	int msgindex;
164
165	BUG_ON(protocol < 0 || protocol >= NPROTO);
166	msgindex = rtm_msgindex(msgtype);
167
168	tab = rtnl_msg_handlers[protocol];
169	if (tab == NULL) {
170		tab = kcalloc(RTM_NR_MSGTYPES, sizeof(*tab), GFP_KERNEL);
171		if (tab == NULL)
172			return -ENOBUFS;
173
174		rtnl_msg_handlers[protocol] = tab;
175	}
176
177	if (doit)
178		tab[msgindex].doit = doit;
179
180	if (dumpit)
181		tab[msgindex].dumpit = dumpit;
182
183	return 0;
184}
185
186EXPORT_SYMBOL_GPL(__rtnl_register);
187
188/**
189 * rtnl_register - Register a rtnetlink message type
190 *
191 * Identical to __rtnl_register() but panics on failure. This is useful
192 * as failure of this function is very unlikely, it can only happen due
193 * to lack of memory when allocating the chain to store all message
194 * handlers for a protocol. Meant for use in init functions where lack
195 * of memory implies no sense in continueing.
196 */
197void rtnl_register(int protocol, int msgtype,
198		   rtnl_doit_func doit, rtnl_dumpit_func dumpit)
199{
200	if (__rtnl_register(protocol, msgtype, doit, dumpit) < 0)
201		panic("Unable to register rtnetlink message handler, "
202		      "protocol = %d, message type = %d\n",
203		      protocol, msgtype);
204}
205
206EXPORT_SYMBOL_GPL(rtnl_register);
207
208/**
209 * rtnl_unregister - Unregister a rtnetlink message type
210 * @protocol: Protocol family or PF_UNSPEC
211 * @msgtype: rtnetlink message type
212 *
213 * Returns 0 on success or a negative error code.
214 */
215int rtnl_unregister(int protocol, int msgtype)
216{
217	int msgindex;
218
219	BUG_ON(protocol < 0 || protocol >= NPROTO);
220	msgindex = rtm_msgindex(msgtype);
221
222	if (rtnl_msg_handlers[protocol] == NULL)
223		return -ENOENT;
224
225	rtnl_msg_handlers[protocol][msgindex].doit = NULL;
226	rtnl_msg_handlers[protocol][msgindex].dumpit = NULL;
227
228	return 0;
229}
230
231EXPORT_SYMBOL_GPL(rtnl_unregister);
232
233/**
234 * rtnl_unregister_all - Unregister all rtnetlink message type of a protocol
235 * @protocol : Protocol family or PF_UNSPEC
236 *
237 * Identical to calling rtnl_unregster() for all registered message types
238 * of a certain protocol family.
239 */
240void rtnl_unregister_all(int protocol)
241{
242	BUG_ON(protocol < 0 || protocol >= NPROTO);
243
244	kfree(rtnl_msg_handlers[protocol]);
245	rtnl_msg_handlers[protocol] = NULL;
246}
247
248EXPORT_SYMBOL_GPL(rtnl_unregister_all);
249
250static const int rtm_min[RTM_NR_FAMILIES] =
251{
252	[RTM_FAM(RTM_NEWLINK)]      = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
253	[RTM_FAM(RTM_NEWADDR)]      = NLMSG_LENGTH(sizeof(struct ifaddrmsg)),
254	[RTM_FAM(RTM_NEWROUTE)]     = NLMSG_LENGTH(sizeof(struct rtmsg)),
255	[RTM_FAM(RTM_NEWRULE)]      = NLMSG_LENGTH(sizeof(struct fib_rule_hdr)),
256	[RTM_FAM(RTM_NEWQDISC)]     = NLMSG_LENGTH(sizeof(struct tcmsg)),
257	[RTM_FAM(RTM_NEWTCLASS)]    = NLMSG_LENGTH(sizeof(struct tcmsg)),
258	[RTM_FAM(RTM_NEWTFILTER)]   = NLMSG_LENGTH(sizeof(struct tcmsg)),
259	[RTM_FAM(RTM_NEWACTION)]    = NLMSG_LENGTH(sizeof(struct tcamsg)),
260	[RTM_FAM(RTM_GETMULTICAST)] = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
261	[RTM_FAM(RTM_GETANYCAST)]   = NLMSG_LENGTH(sizeof(struct rtgenmsg)),
262};
263
264static const int rta_max[RTM_NR_FAMILIES] =
265{
266	[RTM_FAM(RTM_NEWLINK)]      = IFLA_MAX,
267	[RTM_FAM(RTM_NEWADDR)]      = IFA_MAX,
268	[RTM_FAM(RTM_NEWROUTE)]     = RTA_MAX,
269	[RTM_FAM(RTM_NEWRULE)]      = FRA_MAX,
270	[RTM_FAM(RTM_NEWQDISC)]     = TCA_MAX,
271	[RTM_FAM(RTM_NEWTCLASS)]    = TCA_MAX,
272	[RTM_FAM(RTM_NEWTFILTER)]   = TCA_MAX,
273	[RTM_FAM(RTM_NEWACTION)]    = TCAA_MAX,
274};
275
276void __rta_fill(struct sk_buff *skb, int attrtype, int attrlen, const void *data)
277{
278	struct rtattr *rta;
279	int size = RTA_LENGTH(attrlen);
280
281	rta = (struct rtattr*)skb_put(skb, RTA_ALIGN(size));
282	rta->rta_type = attrtype;
283	rta->rta_len = size;
284	memcpy(RTA_DATA(rta), data, attrlen);
285	memset(RTA_DATA(rta) + attrlen, 0, RTA_ALIGN(size) - size);
286}
287
288size_t rtattr_strlcpy(char *dest, const struct rtattr *rta, size_t size)
289{
290	size_t ret = RTA_PAYLOAD(rta);
291	char *src = RTA_DATA(rta);
292
293	if (ret > 0 && src[ret - 1] == '\0')
294		ret--;
295	if (size > 0) {
296		size_t len = (ret >= size) ? size - 1 : ret;
297		memset(dest, 0, size);
298		memcpy(dest, src, len);
299	}
300	return ret;
301}
302
303int rtnetlink_send(struct sk_buff *skb, u32 pid, unsigned group, int echo)
304{
305	int err = 0;
306
307	NETLINK_CB(skb).dst_group = group;
308	if (echo)
309		atomic_inc(&skb->users);
310	netlink_broadcast(rtnl, skb, pid, group, GFP_KERNEL);
311	if (echo)
312		err = netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
313	return err;
314}
315
316int rtnl_unicast(struct sk_buff *skb, u32 pid)
317{
318	return nlmsg_unicast(rtnl, skb, pid);
319}
320
321int rtnl_notify(struct sk_buff *skb, u32 pid, u32 group,
322		struct nlmsghdr *nlh, gfp_t flags)
323{
324	int report = 0;
325
326	if (nlh)
327		report = nlmsg_report(nlh);
328
329	return nlmsg_notify(rtnl, skb, pid, group, report, flags);
330}
331
332void rtnl_set_sk_err(u32 group, int error)
333{
334	netlink_set_err(rtnl, 0, group, error);
335}
336
337int rtnetlink_put_metrics(struct sk_buff *skb, u32 *metrics)
338{
339	struct nlattr *mx;
340	int i, valid = 0;
341
342	mx = nla_nest_start(skb, RTA_METRICS);
343	if (mx == NULL)
344		return -ENOBUFS;
345
346	for (i = 0; i < RTAX_MAX; i++) {
347		if (metrics[i]) {
348			valid++;
349			NLA_PUT_U32(skb, i+1, metrics[i]);
350		}
351	}
352
353	if (!valid) {
354		nla_nest_cancel(skb, mx);
355		return 0;
356	}
357
358	return nla_nest_end(skb, mx);
359
360nla_put_failure:
361	return nla_nest_cancel(skb, mx);
362}
363
364int rtnl_put_cacheinfo(struct sk_buff *skb, struct dst_entry *dst, u32 id,
365		       u32 ts, u32 tsage, long expires, u32 error)
366{
367	struct rta_cacheinfo ci = {
368		.rta_lastuse = jiffies_to_clock_t(jiffies - dst->lastuse),
369		.rta_used = dst->__use,
370		.rta_clntref = atomic_read(&(dst->__refcnt)),
371		.rta_error = error,
372		.rta_id =  id,
373		.rta_ts = ts,
374		.rta_tsage = tsage,
375	};
376
377	if (expires)
378		ci.rta_expires = jiffies_to_clock_t(expires);
379
380	return nla_put(skb, RTA_CACHEINFO, sizeof(ci), &ci);
381}
382
383EXPORT_SYMBOL_GPL(rtnl_put_cacheinfo);
384
385static void set_operstate(struct net_device *dev, unsigned char transition)
386{
387	unsigned char operstate = dev->operstate;
388
389	switch(transition) {
390	case IF_OPER_UP:
391		if ((operstate == IF_OPER_DORMANT ||
392		     operstate == IF_OPER_UNKNOWN) &&
393		    !netif_dormant(dev))
394			operstate = IF_OPER_UP;
395		break;
396
397	case IF_OPER_DORMANT:
398		if (operstate == IF_OPER_UP ||
399		    operstate == IF_OPER_UNKNOWN)
400			operstate = IF_OPER_DORMANT;
401		break;
402	};
403
404	if (dev->operstate != operstate) {
405		write_lock_bh(&dev_base_lock);
406		dev->operstate = operstate;
407		write_unlock_bh(&dev_base_lock);
408		netdev_state_change(dev);
409	}
410}
411
412static void copy_rtnl_link_stats(struct rtnl_link_stats *a,
413				 struct net_device_stats *b)
414{
415	a->rx_packets = b->rx_packets;
416	a->tx_packets = b->tx_packets;
417	a->rx_bytes = b->rx_bytes;
418	a->tx_bytes = b->tx_bytes;
419	a->rx_errors = b->rx_errors;
420	a->tx_errors = b->tx_errors;
421	a->rx_dropped = b->rx_dropped;
422	a->tx_dropped = b->tx_dropped;
423
424	a->multicast = b->multicast;
425	a->collisions = b->collisions;
426
427	a->rx_length_errors = b->rx_length_errors;
428	a->rx_over_errors = b->rx_over_errors;
429	a->rx_crc_errors = b->rx_crc_errors;
430	a->rx_frame_errors = b->rx_frame_errors;
431	a->rx_fifo_errors = b->rx_fifo_errors;
432	a->rx_missed_errors = b->rx_missed_errors;
433
434	a->tx_aborted_errors = b->tx_aborted_errors;
435	a->tx_carrier_errors = b->tx_carrier_errors;
436	a->tx_fifo_errors = b->tx_fifo_errors;
437	a->tx_heartbeat_errors = b->tx_heartbeat_errors;
438	a->tx_window_errors = b->tx_window_errors;
439
440	a->rx_compressed = b->rx_compressed;
441	a->tx_compressed = b->tx_compressed;
442};
443
444static inline size_t if_nlmsg_size(int iwbuflen)
445{
446	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
447	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
448	       + nla_total_size(IFNAMSIZ) /* IFLA_QDISC */
449	       + nla_total_size(sizeof(struct rtnl_link_ifmap))
450	       + nla_total_size(sizeof(struct rtnl_link_stats))
451	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
452	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_BROADCAST */
453	       + nla_total_size(4) /* IFLA_TXQLEN */
454	       + nla_total_size(4) /* IFLA_WEIGHT */
455	       + nla_total_size(4) /* IFLA_MTU */
456	       + nla_total_size(4) /* IFLA_LINK */
457	       + nla_total_size(4) /* IFLA_MASTER */
458	       + nla_total_size(1) /* IFLA_OPERSTATE */
459	       + nla_total_size(1) /* IFLA_LINKMODE */
460	       + nla_total_size(iwbuflen);
461}
462
463static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
464			    void *iwbuf, int iwbuflen, int type, u32 pid,
465			    u32 seq, u32 change, unsigned int flags)
466{
467	struct ifinfomsg *ifm;
468	struct nlmsghdr *nlh;
469
470	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ifm), flags);
471	if (nlh == NULL)
472		return -EMSGSIZE;
473
474	ifm = nlmsg_data(nlh);
475	ifm->ifi_family = AF_UNSPEC;
476	ifm->__ifi_pad = 0;
477	ifm->ifi_type = dev->type;
478	ifm->ifi_index = dev->ifindex;
479	ifm->ifi_flags = dev_get_flags(dev);
480	ifm->ifi_change = change;
481
482	NLA_PUT_STRING(skb, IFLA_IFNAME, dev->name);
483	NLA_PUT_U32(skb, IFLA_TXQLEN, dev->tx_queue_len);
484	NLA_PUT_U32(skb, IFLA_WEIGHT, dev->weight);
485	NLA_PUT_U8(skb, IFLA_OPERSTATE,
486		   netif_running(dev) ? dev->operstate : IF_OPER_DOWN);
487	NLA_PUT_U8(skb, IFLA_LINKMODE, dev->link_mode);
488	NLA_PUT_U32(skb, IFLA_MTU, dev->mtu);
489
490	if (dev->ifindex != dev->iflink)
491		NLA_PUT_U32(skb, IFLA_LINK, dev->iflink);
492
493	if (dev->master)
494		NLA_PUT_U32(skb, IFLA_MASTER, dev->master->ifindex);
495
496	if (dev->qdisc_sleeping)
497		NLA_PUT_STRING(skb, IFLA_QDISC, dev->qdisc_sleeping->ops->id);
498
499	if (1) {
500		struct rtnl_link_ifmap map = {
501			.mem_start   = dev->mem_start,
502			.mem_end     = dev->mem_end,
503			.base_addr   = dev->base_addr,
504			.irq         = dev->irq,
505			.dma         = dev->dma,
506			.port        = dev->if_port,
507		};
508		NLA_PUT(skb, IFLA_MAP, sizeof(map), &map);
509	}
510
511	if (dev->addr_len) {
512		NLA_PUT(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr);
513		NLA_PUT(skb, IFLA_BROADCAST, dev->addr_len, dev->broadcast);
514	}
515
516	if (dev->get_stats) {
517		struct net_device_stats *stats = dev->get_stats(dev);
518		if (stats) {
519			struct nlattr *attr;
520
521			attr = nla_reserve(skb, IFLA_STATS,
522					   sizeof(struct rtnl_link_stats));
523			if (attr == NULL)
524				goto nla_put_failure;
525
526			copy_rtnl_link_stats(nla_data(attr), stats);
527		}
528	}
529
530	if (iwbuf)
531		NLA_PUT(skb, IFLA_WIRELESS, iwbuflen, iwbuf);
532
533	return nlmsg_end(skb, nlh);
534
535nla_put_failure:
536	nlmsg_cancel(skb, nlh);
537	return -EMSGSIZE;
538}
539
540static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
541{
542	int idx;
543	int s_idx = cb->args[0];
544	struct net_device *dev;
545
546	read_lock(&dev_base_lock);
547	for (dev=dev_base, idx=0; dev; dev = dev->next, idx++) {
548		if (idx < s_idx)
549			continue;
550		if (rtnl_fill_ifinfo(skb, dev, NULL, 0, RTM_NEWLINK,
551				     NETLINK_CB(cb->skb).pid,
552				     cb->nlh->nlmsg_seq, 0, NLM_F_MULTI) <= 0)
553			break;
554	}
555	read_unlock(&dev_base_lock);
556	cb->args[0] = idx;
557
558	return skb->len;
559}
560
561static struct nla_policy ifla_policy[IFLA_MAX+1] __read_mostly = {
562	[IFLA_IFNAME]		= { .type = NLA_STRING, .len = IFNAMSIZ-1 },
563	[IFLA_MAP]		= { .len = sizeof(struct rtnl_link_ifmap) },
564	[IFLA_MTU]		= { .type = NLA_U32 },
565	[IFLA_TXQLEN]		= { .type = NLA_U32 },
566	[IFLA_WEIGHT]		= { .type = NLA_U32 },
567	[IFLA_OPERSTATE]	= { .type = NLA_U8 },
568	[IFLA_LINKMODE]		= { .type = NLA_U8 },
569};
570
571static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
572{
573	struct ifinfomsg *ifm;
574	struct net_device *dev;
575	int err, send_addr_notify = 0, modified = 0;
576	struct nlattr *tb[IFLA_MAX+1];
577	char ifname[IFNAMSIZ];
578
579	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
580	if (err < 0)
581		goto errout;
582
583	if (tb[IFLA_IFNAME])
584		nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
585	else
586		ifname[0] = '\0';
587
588	err = -EINVAL;
589	ifm = nlmsg_data(nlh);
590	if (ifm->ifi_index >= 0)
591		dev = dev_get_by_index(ifm->ifi_index);
592	else if (tb[IFLA_IFNAME])
593		dev = dev_get_by_name(ifname);
594	else
595		goto errout;
596
597	if (dev == NULL) {
598		err = -ENODEV;
599		goto errout;
600	}
601
602	if (tb[IFLA_ADDRESS] &&
603	    nla_len(tb[IFLA_ADDRESS]) < dev->addr_len)
604		goto errout_dev;
605
606	if (tb[IFLA_BROADCAST] &&
607	    nla_len(tb[IFLA_BROADCAST]) < dev->addr_len)
608		goto errout_dev;
609
610	if (tb[IFLA_MAP]) {
611		struct rtnl_link_ifmap *u_map;
612		struct ifmap k_map;
613
614		if (!dev->set_config) {
615			err = -EOPNOTSUPP;
616			goto errout_dev;
617		}
618
619		if (!netif_device_present(dev)) {
620			err = -ENODEV;
621			goto errout_dev;
622		}
623
624		u_map = nla_data(tb[IFLA_MAP]);
625		k_map.mem_start = (unsigned long) u_map->mem_start;
626		k_map.mem_end = (unsigned long) u_map->mem_end;
627		k_map.base_addr = (unsigned short) u_map->base_addr;
628		k_map.irq = (unsigned char) u_map->irq;
629		k_map.dma = (unsigned char) u_map->dma;
630		k_map.port = (unsigned char) u_map->port;
631
632		err = dev->set_config(dev, &k_map);
633		if (err < 0)
634			goto errout_dev;
635
636		modified = 1;
637	}
638
639	if (tb[IFLA_ADDRESS]) {
640		struct sockaddr *sa;
641		int len;
642
643		if (!dev->set_mac_address) {
644			err = -EOPNOTSUPP;
645			goto errout_dev;
646		}
647
648		if (!netif_device_present(dev)) {
649			err = -ENODEV;
650			goto errout_dev;
651		}
652
653		len = sizeof(sa_family_t) + dev->addr_len;
654		sa = kmalloc(len, GFP_KERNEL);
655		if (!sa) {
656			err = -ENOMEM;
657			goto errout_dev;
658		}
659		sa->sa_family = dev->type;
660		memcpy(sa->sa_data, nla_data(tb[IFLA_ADDRESS]),
661		       dev->addr_len);
662		err = dev->set_mac_address(dev, sa);
663		kfree(sa);
664		if (err)
665			goto errout_dev;
666		send_addr_notify = 1;
667		modified = 1;
668	}
669
670	if (tb[IFLA_MTU]) {
671		err = dev_set_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
672		if (err < 0)
673			goto errout_dev;
674		modified = 1;
675	}
676
677	/*
678	 * Interface selected by interface index but interface
679	 * name provided implies that a name change has been
680	 * requested.
681	 */
682	if (ifm->ifi_index >= 0 && ifname[0]) {
683		err = dev_change_name(dev, ifname);
684		if (err < 0)
685			goto errout_dev;
686		modified = 1;
687	}
688
689#ifdef CONFIG_NET_WIRELESS_RTNETLINK
690	if (tb[IFLA_WIRELESS]) {
691		/* Call Wireless Extensions.
692		 * Various stuff checked in there... */
693		err = wireless_rtnetlink_set(dev, nla_data(tb[IFLA_WIRELESS]),
694					     nla_len(tb[IFLA_WIRELESS]));
695		if (err < 0)
696			goto errout_dev;
697	}
698#endif	/* CONFIG_NET_WIRELESS_RTNETLINK */
699
700	if (tb[IFLA_BROADCAST]) {
701		nla_memcpy(dev->broadcast, tb[IFLA_BROADCAST], dev->addr_len);
702		send_addr_notify = 1;
703	}
704
705
706	if (ifm->ifi_flags)
707		dev_change_flags(dev, ifm->ifi_flags);
708
709	if (tb[IFLA_TXQLEN])
710		dev->tx_queue_len = nla_get_u32(tb[IFLA_TXQLEN]);
711
712	if (tb[IFLA_WEIGHT])
713		dev->weight = nla_get_u32(tb[IFLA_WEIGHT]);
714
715	if (tb[IFLA_OPERSTATE])
716		set_operstate(dev, nla_get_u8(tb[IFLA_OPERSTATE]));
717
718	if (tb[IFLA_LINKMODE]) {
719		write_lock_bh(&dev_base_lock);
720		dev->link_mode = nla_get_u8(tb[IFLA_LINKMODE]);
721		write_unlock_bh(&dev_base_lock);
722	}
723
724	err = 0;
725
726errout_dev:
727	if (err < 0 && modified && net_ratelimit())
728		printk(KERN_WARNING "A link change request failed with "
729		       "some changes comitted already. Interface %s may "
730		       "have been left with an inconsistent configuration, "
731		       "please check.\n", dev->name);
732
733	if (send_addr_notify)
734		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
735
736	dev_put(dev);
737errout:
738	return err;
739}
740
741static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
742{
743	struct ifinfomsg *ifm;
744	struct nlattr *tb[IFLA_MAX+1];
745	struct net_device *dev = NULL;
746	struct sk_buff *nskb;
747	char *iw_buf = NULL, *iw = NULL;
748	int iw_buf_len = 0;
749	int err;
750
751	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy);
752	if (err < 0)
753		return err;
754
755	ifm = nlmsg_data(nlh);
756	if (ifm->ifi_index >= 0) {
757		dev = dev_get_by_index(ifm->ifi_index);
758		if (dev == NULL)
759			return -ENODEV;
760	} else
761		return -EINVAL;
762
763
764#ifdef CONFIG_NET_WIRELESS_RTNETLINK
765	if (tb[IFLA_WIRELESS]) {
766		/* Call Wireless Extensions. We need to know the size before
767		 * we can alloc. Various stuff checked in there... */
768		err = wireless_rtnetlink_get(dev, nla_data(tb[IFLA_WIRELESS]),
769					     nla_len(tb[IFLA_WIRELESS]),
770					     &iw_buf, &iw_buf_len);
771		if (err < 0)
772			goto errout;
773
774		/* Payload is at an offset in buffer */
775		iw = iw_buf + IW_EV_POINT_OFF;
776	}
777#endif	/* CONFIG_NET_WIRELESS_RTNETLINK */
778
779	nskb = nlmsg_new(if_nlmsg_size(iw_buf_len), GFP_KERNEL);
780	if (nskb == NULL) {
781		err = -ENOBUFS;
782		goto errout;
783	}
784
785	err = rtnl_fill_ifinfo(nskb, dev, iw, iw_buf_len, RTM_NEWLINK,
786			       NETLINK_CB(skb).pid, nlh->nlmsg_seq, 0, 0);
787	if (err < 0) {
788		/* -EMSGSIZE implies BUG in if_nlmsg_size */
789		WARN_ON(err == -EMSGSIZE);
790		kfree_skb(nskb);
791		goto errout;
792	}
793	err = rtnl_unicast(nskb, NETLINK_CB(skb).pid);
794errout:
795	kfree(iw_buf);
796	dev_put(dev);
797
798	return err;
799}
800
801int rtnl_dump_all(struct sk_buff *skb, struct netlink_callback *cb)
802{
803	int idx;
804	int s_idx = cb->family;
805
806	if (s_idx == 0)
807		s_idx = 1;
808	for (idx=1; idx<NPROTO; idx++) {
809		int type = cb->nlh->nlmsg_type-RTM_BASE;
810		if (idx < s_idx || idx == PF_PACKET)
811			continue;
812		if (rtnl_msg_handlers[idx] == NULL ||
813		    rtnl_msg_handlers[idx][type].dumpit == NULL)
814			continue;
815		if (idx > s_idx)
816			memset(&cb->args[0], 0, sizeof(cb->args));
817		if (rtnl_msg_handlers[idx][type].dumpit(skb, cb))
818			break;
819	}
820	cb->family = idx;
821
822	return skb->len;
823}
824
825EXPORT_SYMBOL_GPL(rtnl_dump_all);
826
827void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change)
828{
829	struct sk_buff *skb;
830	int err = -ENOBUFS;
831
832	skb = nlmsg_new(if_nlmsg_size(0), GFP_KERNEL);
833	if (skb == NULL)
834		goto errout;
835
836	err = rtnl_fill_ifinfo(skb, dev, NULL, 0, type, 0, 0, change, 0);
837	if (err < 0) {
838		/* -EMSGSIZE implies BUG in if_nlmsg_size() */
839		WARN_ON(err == -EMSGSIZE);
840		kfree_skb(skb);
841		goto errout;
842	}
843	err = rtnl_notify(skb, 0, RTNLGRP_LINK, NULL, GFP_KERNEL);
844errout:
845	if (err < 0)
846		rtnl_set_sk_err(RTNLGRP_LINK, err);
847}
848
849/* Protected by RTNL sempahore.  */
850static struct rtattr **rta_buf;
851static int rtattr_max;
852
853/* Process one rtnetlink message. */
854
855static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
856{
857	rtnl_doit_func doit;
858	int sz_idx, kind;
859	int min_len;
860	int family;
861	int type;
862	int err;
863
864	type = nlh->nlmsg_type;
865	if (type > RTM_MAX)
866		return -EINVAL;
867
868	type -= RTM_BASE;
869
870	/* All the messages must have at least 1 byte length */
871	if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(struct rtgenmsg)))
872		return 0;
873
874	family = ((struct rtgenmsg*)NLMSG_DATA(nlh))->rtgen_family;
875	if (family >= NPROTO)
876		return -EAFNOSUPPORT;
877
878	sz_idx = type>>2;
879	kind = type&3;
880
881	if (kind != 2 && security_netlink_recv(skb, CAP_NET_ADMIN))
882		return -EPERM;
883
884	if (kind == 2 && nlh->nlmsg_flags&NLM_F_DUMP) {
885		rtnl_dumpit_func dumpit;
886
887		dumpit = rtnl_get_dumpit(family, type);
888		if (dumpit == NULL)
889			return -EINVAL;
890
891		err = netlink_dump_start(rtnl, skb, nlh, dumpit, NULL);
892		if (err == 0)
893			err = -EINTR;
894		return err;
895	}
896
897	memset(rta_buf, 0, (rtattr_max * sizeof(struct rtattr *)));
898
899	min_len = rtm_min[sz_idx];
900	if (nlh->nlmsg_len < min_len)
901		return -EINVAL;
902
903	if (nlh->nlmsg_len > min_len) {
904		int attrlen = nlh->nlmsg_len - NLMSG_ALIGN(min_len);
905		struct rtattr *attr = (void*)nlh + NLMSG_ALIGN(min_len);
906
907		while (RTA_OK(attr, attrlen)) {
908			unsigned flavor = attr->rta_type;
909			if (flavor) {
910				if (flavor > rta_max[sz_idx])
911					return -EINVAL;
912				rta_buf[flavor-1] = attr;
913			}
914			attr = RTA_NEXT(attr, attrlen);
915		}
916	}
917
918	doit = rtnl_get_doit(family, type);
919	if (doit == NULL)
920		return -EINVAL;
921
922	return doit(skb, nlh, (void *)&rta_buf[0]);
923}
924
925static void rtnetlink_rcv(struct sock *sk, int len)
926{
927	unsigned int qlen = 0;
928
929	do {
930		mutex_lock(&rtnl_mutex);
931		netlink_run_queue(sk, &qlen, &rtnetlink_rcv_msg);
932		mutex_unlock(&rtnl_mutex);
933
934		netdev_run_todo();
935	} while (qlen);
936}
937
938static int rtnetlink_event(struct notifier_block *this, unsigned long event, void *ptr)
939{
940	struct net_device *dev = ptr;
941	switch (event) {
942	case NETDEV_UNREGISTER:
943		rtmsg_ifinfo(RTM_DELLINK, dev, ~0U);
944		break;
945	case NETDEV_REGISTER:
946		rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
947		break;
948	case NETDEV_UP:
949	case NETDEV_DOWN:
950		rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
951		break;
952	case NETDEV_CHANGE:
953	case NETDEV_GOING_DOWN:
954		break;
955	default:
956		rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
957		break;
958	}
959	return NOTIFY_DONE;
960}
961
962static struct notifier_block rtnetlink_dev_notifier = {
963	.notifier_call	= rtnetlink_event,
964};
965
966void __init rtnetlink_init(void)
967{
968	int i;
969
970	rtattr_max = 0;
971	for (i = 0; i < ARRAY_SIZE(rta_max); i++)
972		if (rta_max[i] > rtattr_max)
973			rtattr_max = rta_max[i];
974	rta_buf = kmalloc(rtattr_max * sizeof(struct rtattr *), GFP_KERNEL);
975	if (!rta_buf)
976		panic("rtnetlink_init: cannot allocate rta_buf\n");
977
978	rtnl = netlink_kernel_create(NETLINK_ROUTE, RTNLGRP_MAX, rtnetlink_rcv,
979				     THIS_MODULE);
980	if (rtnl == NULL)
981		panic("rtnetlink_init: cannot initialize rtnetlink\n");
982	netlink_set_nonroot(NETLINK_ROUTE, NL_NONROOT_RECV);
983	register_netdevice_notifier(&rtnetlink_dev_notifier);
984
985	rtnl_register(PF_UNSPEC, RTM_GETLINK, rtnl_getlink, rtnl_dump_ifinfo);
986	rtnl_register(PF_UNSPEC, RTM_SETLINK, rtnl_setlink, NULL);
987
988	rtnl_register(PF_UNSPEC, RTM_GETADDR, NULL, rtnl_dump_all);
989	rtnl_register(PF_UNSPEC, RTM_GETROUTE, NULL, rtnl_dump_all);
990}
991
992EXPORT_SYMBOL(__rta_fill);
993EXPORT_SYMBOL(rtattr_strlcpy);
994EXPORT_SYMBOL(rtattr_parse);
995EXPORT_SYMBOL(rtnetlink_put_metrics);
996EXPORT_SYMBOL(rtnl_lock);
997EXPORT_SYMBOL(rtnl_trylock);
998EXPORT_SYMBOL(rtnl_unlock);
999EXPORT_SYMBOL(rtnl_unicast);
1000EXPORT_SYMBOL(rtnl_notify);
1001EXPORT_SYMBOL(rtnl_set_sk_err);
1002