1 /*
2 * NET3 IP device support routines.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 * Derived from the IP parts of dev.c 1.0.19
10 * Authors: Ross Biro
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Mark Evans, <evansmp@uhura.aston.ac.uk>
13 *
14 * Additional Authors:
15 * Alan Cox, <gw4pts@gw4pts.ampr.org>
16 * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
17 *
18 * Changes:
19 * Alexey Kuznetsov: pa_* fields are replaced with ifaddr
20 * lists.
21 * Cyrus Durgin: updated for kmod
22 * Matthias Andree: in devinet_ioctl, compare label and
23 * address (4.4BSD alias style support),
24 * fall back to comparing just the label
25 * if no match found.
26 */
27
28
29 #include <asm/uaccess.h>
30 #include <asm/system.h>
31 #include <linux/bitops.h>
32 #include <linux/capability.h>
33 #include <linux/module.h>
34 #include <linux/types.h>
35 #include <linux/kernel.h>
36 #include <linux/string.h>
37 #include <linux/mm.h>
38 #include <linux/socket.h>
39 #include <linux/sockios.h>
40 #include <linux/in.h>
41 #include <linux/errno.h>
42 #include <linux/interrupt.h>
43 #include <linux/if_addr.h>
44 #include <linux/if_ether.h>
45 #include <linux/inet.h>
46 #include <linux/netdevice.h>
47 #include <linux/etherdevice.h>
48 #include <linux/skbuff.h>
49 #include <linux/init.h>
50 #include <linux/notifier.h>
51 #include <linux/inetdevice.h>
52 #include <linux/igmp.h>
53 #include <linux/slab.h>
54 #include <linux/hash.h>
55 #ifdef CONFIG_SYSCTL
56 #include <linux/sysctl.h>
57 #endif
58 #include <linux/kmod.h>
59
60 #include <net/arp.h>
61 #include <net/ip.h>
62 #include <net/route.h>
63 #include <net/ip_fib.h>
64 #include <net/rtnetlink.h>
65 #include <net/net_namespace.h>
66
67 #include "fib_lookup.h"
68
69 static struct ipv4_devconf ipv4_devconf = {
70 .data = {
71 [IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1,
72 [IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1,
73 [IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1,
74 [IPV4_DEVCONF_SHARED_MEDIA - 1] = 1,
75 },
76 };
77
78 static struct ipv4_devconf ipv4_devconf_dflt = {
79 .data = {
80 [IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1,
81 [IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1,
82 [IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1,
83 [IPV4_DEVCONF_SHARED_MEDIA - 1] = 1,
84 [IPV4_DEVCONF_ACCEPT_SOURCE_ROUTE - 1] = 1,
85 },
86 };
87
88 #define IPV4_DEVCONF_DFLT(net, attr) \
89 IPV4_DEVCONF((*net->ipv4.devconf_dflt), attr)
90
91 static const struct nla_policy ifa_ipv4_policy[IFA_MAX+1] = {
92 [IFA_LOCAL] = { .type = NLA_U32 },
93 [IFA_ADDRESS] = { .type = NLA_U32 },
94 [IFA_BROADCAST] = { .type = NLA_U32 },
95 [IFA_LABEL] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
96 };
97
98 /* inet_addr_hash's shifting is dependent upon this IN4_ADDR_HSIZE
99 * value. So if you change this define, make appropriate changes to
100 * inet_addr_hash as well.
101 */
102 #define IN4_ADDR_HSIZE 256
103 static struct hlist_head inet_addr_lst[IN4_ADDR_HSIZE];
104 static DEFINE_SPINLOCK(inet_addr_hash_lock);
105
inet_addr_hash(struct net * net,__be32 addr)106 static inline unsigned int inet_addr_hash(struct net *net, __be32 addr)
107 {
108 u32 val = (__force u32) addr ^ hash_ptr(net, 8);
109
110 return ((val ^ (val >> 8) ^ (val >> 16) ^ (val >> 24)) &
111 (IN4_ADDR_HSIZE - 1));
112 }
113
inet_hash_insert(struct net * net,struct in_ifaddr * ifa)114 static void inet_hash_insert(struct net *net, struct in_ifaddr *ifa)
115 {
116 unsigned int hash = inet_addr_hash(net, ifa->ifa_local);
117
118 spin_lock(&inet_addr_hash_lock);
119 hlist_add_head_rcu(&ifa->hash, &inet_addr_lst[hash]);
120 spin_unlock(&inet_addr_hash_lock);
121 }
122
inet_hash_remove(struct in_ifaddr * ifa)123 static void inet_hash_remove(struct in_ifaddr *ifa)
124 {
125 spin_lock(&inet_addr_hash_lock);
126 hlist_del_init_rcu(&ifa->hash);
127 spin_unlock(&inet_addr_hash_lock);
128 }
129
130 /**
131 * __ip_dev_find - find the first device with a given source address.
132 * @net: the net namespace
133 * @addr: the source address
134 * @devref: if true, take a reference on the found device
135 *
136 * If a caller uses devref=false, it should be protected by RCU, or RTNL
137 */
__ip_dev_find(struct net * net,__be32 addr,bool devref)138 struct net_device *__ip_dev_find(struct net *net, __be32 addr, bool devref)
139 {
140 unsigned int hash = inet_addr_hash(net, addr);
141 struct net_device *result = NULL;
142 struct in_ifaddr *ifa;
143 struct hlist_node *node;
144
145 rcu_read_lock();
146 hlist_for_each_entry_rcu(ifa, node, &inet_addr_lst[hash], hash) {
147 struct net_device *dev = ifa->ifa_dev->dev;
148
149 if (!net_eq(dev_net(dev), net))
150 continue;
151 if (ifa->ifa_local == addr) {
152 result = dev;
153 break;
154 }
155 }
156 if (!result) {
157 struct flowi4 fl4 = { .daddr = addr };
158 struct fib_result res = { 0 };
159 struct fib_table *local;
160
161 /* Fallback to FIB local table so that communication
162 * over loopback subnets work.
163 */
164 local = fib_get_table(net, RT_TABLE_LOCAL);
165 if (local &&
166 !fib_table_lookup(local, &fl4, &res, FIB_LOOKUP_NOREF) &&
167 res.type == RTN_LOCAL)
168 result = FIB_RES_DEV(res);
169 }
170 if (result && devref)
171 dev_hold(result);
172 rcu_read_unlock();
173 return result;
174 }
175 EXPORT_SYMBOL(__ip_dev_find);
176
177 static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32);
178
179 static BLOCKING_NOTIFIER_HEAD(inetaddr_chain);
180 static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
181 int destroy);
182 #ifdef CONFIG_SYSCTL
183 static void devinet_sysctl_register(struct in_device *idev);
184 static void devinet_sysctl_unregister(struct in_device *idev);
185 #else
devinet_sysctl_register(struct in_device * idev)186 static inline void devinet_sysctl_register(struct in_device *idev)
187 {
188 }
devinet_sysctl_unregister(struct in_device * idev)189 static inline void devinet_sysctl_unregister(struct in_device *idev)
190 {
191 }
192 #endif
193
194 /* Locks all the inet devices. */
195
inet_alloc_ifa(void)196 static struct in_ifaddr *inet_alloc_ifa(void)
197 {
198 return kzalloc(sizeof(struct in_ifaddr), GFP_KERNEL);
199 }
200
inet_rcu_free_ifa(struct rcu_head * head)201 static void inet_rcu_free_ifa(struct rcu_head *head)
202 {
203 struct in_ifaddr *ifa = container_of(head, struct in_ifaddr, rcu_head);
204 if (ifa->ifa_dev)
205 in_dev_put(ifa->ifa_dev);
206 kfree(ifa);
207 }
208
inet_free_ifa(struct in_ifaddr * ifa)209 static inline void inet_free_ifa(struct in_ifaddr *ifa)
210 {
211 call_rcu(&ifa->rcu_head, inet_rcu_free_ifa);
212 }
213
in_dev_finish_destroy(struct in_device * idev)214 void in_dev_finish_destroy(struct in_device *idev)
215 {
216 struct net_device *dev = idev->dev;
217
218 WARN_ON(idev->ifa_list);
219 WARN_ON(idev->mc_list);
220 #ifdef NET_REFCNT_DEBUG
221 printk(KERN_DEBUG "in_dev_finish_destroy: %p=%s\n",
222 idev, dev ? dev->name : "NIL");
223 #endif
224 dev_put(dev);
225 if (!idev->dead)
226 pr_err("Freeing alive in_device %p\n", idev);
227 else
228 kfree(idev);
229 }
230 EXPORT_SYMBOL(in_dev_finish_destroy);
231
inetdev_init(struct net_device * dev)232 static struct in_device *inetdev_init(struct net_device *dev)
233 {
234 struct in_device *in_dev;
235
236 ASSERT_RTNL();
237
238 in_dev = kzalloc(sizeof(*in_dev), GFP_KERNEL);
239 if (!in_dev)
240 goto out;
241 memcpy(&in_dev->cnf, dev_net(dev)->ipv4.devconf_dflt,
242 sizeof(in_dev->cnf));
243 in_dev->cnf.sysctl = NULL;
244 in_dev->dev = dev;
245 in_dev->arp_parms = neigh_parms_alloc(dev, &arp_tbl);
246 if (!in_dev->arp_parms)
247 goto out_kfree;
248 if (IPV4_DEVCONF(in_dev->cnf, FORWARDING))
249 dev_disable_lro(dev);
250 /* Reference in_dev->dev */
251 dev_hold(dev);
252 /* Account for reference dev->ip_ptr (below) */
253 in_dev_hold(in_dev);
254
255 devinet_sysctl_register(in_dev);
256 ip_mc_init_dev(in_dev);
257 if (dev->flags & IFF_UP)
258 ip_mc_up(in_dev);
259
260 /* we can receive as soon as ip_ptr is set -- do this last */
261 rcu_assign_pointer(dev->ip_ptr, in_dev);
262 out:
263 return in_dev;
264 out_kfree:
265 kfree(in_dev);
266 in_dev = NULL;
267 goto out;
268 }
269
in_dev_rcu_put(struct rcu_head * head)270 static void in_dev_rcu_put(struct rcu_head *head)
271 {
272 struct in_device *idev = container_of(head, struct in_device, rcu_head);
273 in_dev_put(idev);
274 }
275
inetdev_destroy(struct in_device * in_dev)276 static void inetdev_destroy(struct in_device *in_dev)
277 {
278 struct in_ifaddr *ifa;
279 struct net_device *dev;
280
281 ASSERT_RTNL();
282
283 dev = in_dev->dev;
284
285 in_dev->dead = 1;
286
287 ip_mc_destroy_dev(in_dev);
288
289 while ((ifa = in_dev->ifa_list) != NULL) {
290 inet_del_ifa(in_dev, &in_dev->ifa_list, 0);
291 inet_free_ifa(ifa);
292 }
293
294 rcu_assign_pointer(dev->ip_ptr, NULL);
295
296 devinet_sysctl_unregister(in_dev);
297 neigh_parms_release(&arp_tbl, in_dev->arp_parms);
298 arp_ifdown(dev);
299
300 call_rcu(&in_dev->rcu_head, in_dev_rcu_put);
301 }
302
inet_addr_onlink(struct in_device * in_dev,__be32 a,__be32 b)303 int inet_addr_onlink(struct in_device *in_dev, __be32 a, __be32 b)
304 {
305 rcu_read_lock();
306 for_primary_ifa(in_dev) {
307 if (inet_ifa_match(a, ifa)) {
308 if (!b || inet_ifa_match(b, ifa)) {
309 rcu_read_unlock();
310 return 1;
311 }
312 }
313 } endfor_ifa(in_dev);
314 rcu_read_unlock();
315 return 0;
316 }
317
__inet_del_ifa(struct in_device * in_dev,struct in_ifaddr ** ifap,int destroy,struct nlmsghdr * nlh,u32 pid)318 static void __inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
319 int destroy, struct nlmsghdr *nlh, u32 pid)
320 {
321 struct in_ifaddr *promote = NULL;
322 struct in_ifaddr *ifa, *ifa1 = *ifap;
323 struct in_ifaddr *last_prim = in_dev->ifa_list;
324 struct in_ifaddr *prev_prom = NULL;
325 int do_promote = IN_DEV_PROMOTE_SECONDARIES(in_dev);
326
327 ASSERT_RTNL();
328
329 /* 1. Deleting primary ifaddr forces deletion all secondaries
330 * unless alias promotion is set
331 **/
332
333 if (!(ifa1->ifa_flags & IFA_F_SECONDARY)) {
334 struct in_ifaddr **ifap1 = &ifa1->ifa_next;
335
336 while ((ifa = *ifap1) != NULL) {
337 if (!(ifa->ifa_flags & IFA_F_SECONDARY) &&
338 ifa1->ifa_scope <= ifa->ifa_scope)
339 last_prim = ifa;
340
341 if (!(ifa->ifa_flags & IFA_F_SECONDARY) ||
342 ifa1->ifa_mask != ifa->ifa_mask ||
343 !inet_ifa_match(ifa1->ifa_address, ifa)) {
344 ifap1 = &ifa->ifa_next;
345 prev_prom = ifa;
346 continue;
347 }
348
349 if (!do_promote) {
350 inet_hash_remove(ifa);
351 *ifap1 = ifa->ifa_next;
352
353 rtmsg_ifa(RTM_DELADDR, ifa, nlh, pid);
354 blocking_notifier_call_chain(&inetaddr_chain,
355 NETDEV_DOWN, ifa);
356 inet_free_ifa(ifa);
357 } else {
358 promote = ifa;
359 break;
360 }
361 }
362 }
363
364 /* On promotion all secondaries from subnet are changing
365 * the primary IP, we must remove all their routes silently
366 * and later to add them back with new prefsrc. Do this
367 * while all addresses are on the device list.
368 */
369 for (ifa = promote; ifa; ifa = ifa->ifa_next) {
370 if (ifa1->ifa_mask == ifa->ifa_mask &&
371 inet_ifa_match(ifa1->ifa_address, ifa))
372 fib_del_ifaddr(ifa, ifa1);
373 }
374
375 /* 2. Unlink it */
376
377 *ifap = ifa1->ifa_next;
378 inet_hash_remove(ifa1);
379
380 /* 3. Announce address deletion */
381
382 /* Send message first, then call notifier.
383 At first sight, FIB update triggered by notifier
384 will refer to already deleted ifaddr, that could confuse
385 netlink listeners. It is not true: look, gated sees
386 that route deleted and if it still thinks that ifaddr
387 is valid, it will try to restore deleted routes... Grr.
388 So that, this order is correct.
389 */
390 rtmsg_ifa(RTM_DELADDR, ifa1, nlh, pid);
391 blocking_notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa1);
392
393 if (promote) {
394 struct in_ifaddr *next_sec = promote->ifa_next;
395
396 if (prev_prom) {
397 prev_prom->ifa_next = promote->ifa_next;
398 promote->ifa_next = last_prim->ifa_next;
399 last_prim->ifa_next = promote;
400 }
401
402 promote->ifa_flags &= ~IFA_F_SECONDARY;
403 rtmsg_ifa(RTM_NEWADDR, promote, nlh, pid);
404 blocking_notifier_call_chain(&inetaddr_chain,
405 NETDEV_UP, promote);
406 for (ifa = next_sec; ifa; ifa = ifa->ifa_next) {
407 if (ifa1->ifa_mask != ifa->ifa_mask ||
408 !inet_ifa_match(ifa1->ifa_address, ifa))
409 continue;
410 fib_add_ifaddr(ifa);
411 }
412
413 }
414 if (destroy)
415 inet_free_ifa(ifa1);
416 }
417
inet_del_ifa(struct in_device * in_dev,struct in_ifaddr ** ifap,int destroy)418 static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
419 int destroy)
420 {
421 __inet_del_ifa(in_dev, ifap, destroy, NULL, 0);
422 }
423
__inet_insert_ifa(struct in_ifaddr * ifa,struct nlmsghdr * nlh,u32 pid)424 static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh,
425 u32 pid)
426 {
427 struct in_device *in_dev = ifa->ifa_dev;
428 struct in_ifaddr *ifa1, **ifap, **last_primary;
429
430 ASSERT_RTNL();
431
432 if (!ifa->ifa_local) {
433 inet_free_ifa(ifa);
434 return 0;
435 }
436
437 ifa->ifa_flags &= ~IFA_F_SECONDARY;
438 last_primary = &in_dev->ifa_list;
439
440 for (ifap = &in_dev->ifa_list; (ifa1 = *ifap) != NULL;
441 ifap = &ifa1->ifa_next) {
442 if (!(ifa1->ifa_flags & IFA_F_SECONDARY) &&
443 ifa->ifa_scope <= ifa1->ifa_scope)
444 last_primary = &ifa1->ifa_next;
445 if (ifa1->ifa_mask == ifa->ifa_mask &&
446 inet_ifa_match(ifa1->ifa_address, ifa)) {
447 if (ifa1->ifa_local == ifa->ifa_local) {
448 inet_free_ifa(ifa);
449 return -EEXIST;
450 }
451 if (ifa1->ifa_scope != ifa->ifa_scope) {
452 inet_free_ifa(ifa);
453 return -EINVAL;
454 }
455 ifa->ifa_flags |= IFA_F_SECONDARY;
456 }
457 }
458
459 if (!(ifa->ifa_flags & IFA_F_SECONDARY)) {
460 net_srandom(ifa->ifa_local);
461 ifap = last_primary;
462 }
463
464 ifa->ifa_next = *ifap;
465 *ifap = ifa;
466
467 inet_hash_insert(dev_net(in_dev->dev), ifa);
468
469 /* Send message first, then call notifier.
470 Notifier will trigger FIB update, so that
471 listeners of netlink will know about new ifaddr */
472 rtmsg_ifa(RTM_NEWADDR, ifa, nlh, pid);
473 blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa);
474
475 return 0;
476 }
477
inet_insert_ifa(struct in_ifaddr * ifa)478 static int inet_insert_ifa(struct in_ifaddr *ifa)
479 {
480 return __inet_insert_ifa(ifa, NULL, 0);
481 }
482
inet_set_ifa(struct net_device * dev,struct in_ifaddr * ifa)483 static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa)
484 {
485 struct in_device *in_dev = __in_dev_get_rtnl(dev);
486
487 ASSERT_RTNL();
488
489 if (!in_dev) {
490 inet_free_ifa(ifa);
491 return -ENOBUFS;
492 }
493 ipv4_devconf_setall(in_dev);
494 if (ifa->ifa_dev != in_dev) {
495 WARN_ON(ifa->ifa_dev);
496 in_dev_hold(in_dev);
497 ifa->ifa_dev = in_dev;
498 }
499 if (ipv4_is_loopback(ifa->ifa_local))
500 ifa->ifa_scope = RT_SCOPE_HOST;
501 return inet_insert_ifa(ifa);
502 }
503
504 /* Caller must hold RCU or RTNL :
505 * We dont take a reference on found in_device
506 */
inetdev_by_index(struct net * net,int ifindex)507 struct in_device *inetdev_by_index(struct net *net, int ifindex)
508 {
509 struct net_device *dev;
510 struct in_device *in_dev = NULL;
511
512 rcu_read_lock();
513 dev = dev_get_by_index_rcu(net, ifindex);
514 if (dev)
515 in_dev = rcu_dereference_rtnl(dev->ip_ptr);
516 rcu_read_unlock();
517 return in_dev;
518 }
519 EXPORT_SYMBOL(inetdev_by_index);
520
521 /* Called only from RTNL semaphored context. No locks. */
522
inet_ifa_byprefix(struct in_device * in_dev,__be32 prefix,__be32 mask)523 struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix,
524 __be32 mask)
525 {
526 ASSERT_RTNL();
527
528 for_primary_ifa(in_dev) {
529 if (ifa->ifa_mask == mask && inet_ifa_match(prefix, ifa))
530 return ifa;
531 } endfor_ifa(in_dev);
532 return NULL;
533 }
534
inet_rtm_deladdr(struct sk_buff * skb,struct nlmsghdr * nlh,void * arg)535 static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
536 {
537 struct net *net = sock_net(skb->sk);
538 struct nlattr *tb[IFA_MAX+1];
539 struct in_device *in_dev;
540 struct ifaddrmsg *ifm;
541 struct in_ifaddr *ifa, **ifap;
542 int err = -EINVAL;
543
544 ASSERT_RTNL();
545
546 err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy);
547 if (err < 0)
548 goto errout;
549
550 ifm = nlmsg_data(nlh);
551 in_dev = inetdev_by_index(net, ifm->ifa_index);
552 if (in_dev == NULL) {
553 err = -ENODEV;
554 goto errout;
555 }
556
557 for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
558 ifap = &ifa->ifa_next) {
559 if (tb[IFA_LOCAL] &&
560 ifa->ifa_local != nla_get_be32(tb[IFA_LOCAL]))
561 continue;
562
563 if (tb[IFA_LABEL] && nla_strcmp(tb[IFA_LABEL], ifa->ifa_label))
564 continue;
565
566 if (tb[IFA_ADDRESS] &&
567 (ifm->ifa_prefixlen != ifa->ifa_prefixlen ||
568 !inet_ifa_match(nla_get_be32(tb[IFA_ADDRESS]), ifa)))
569 continue;
570
571 __inet_del_ifa(in_dev, ifap, 1, nlh, NETLINK_CB(skb).pid);
572 return 0;
573 }
574
575 err = -EADDRNOTAVAIL;
576 errout:
577 return err;
578 }
579
rtm_to_ifaddr(struct net * net,struct nlmsghdr * nlh)580 static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh)
581 {
582 struct nlattr *tb[IFA_MAX+1];
583 struct in_ifaddr *ifa;
584 struct ifaddrmsg *ifm;
585 struct net_device *dev;
586 struct in_device *in_dev;
587 int err;
588
589 err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv4_policy);
590 if (err < 0)
591 goto errout;
592
593 ifm = nlmsg_data(nlh);
594 err = -EINVAL;
595 if (ifm->ifa_prefixlen > 32 || tb[IFA_LOCAL] == NULL)
596 goto errout;
597
598 dev = __dev_get_by_index(net, ifm->ifa_index);
599 err = -ENODEV;
600 if (dev == NULL)
601 goto errout;
602
603 in_dev = __in_dev_get_rtnl(dev);
604 err = -ENOBUFS;
605 if (in_dev == NULL)
606 goto errout;
607
608 ifa = inet_alloc_ifa();
609 if (ifa == NULL)
610 /*
611 * A potential indev allocation can be left alive, it stays
612 * assigned to its device and is destroy with it.
613 */
614 goto errout;
615
616 ipv4_devconf_setall(in_dev);
617 in_dev_hold(in_dev);
618
619 if (tb[IFA_ADDRESS] == NULL)
620 tb[IFA_ADDRESS] = tb[IFA_LOCAL];
621
622 INIT_HLIST_NODE(&ifa->hash);
623 ifa->ifa_prefixlen = ifm->ifa_prefixlen;
624 ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen);
625 ifa->ifa_flags = ifm->ifa_flags;
626 ifa->ifa_scope = ifm->ifa_scope;
627 ifa->ifa_dev = in_dev;
628
629 ifa->ifa_local = nla_get_be32(tb[IFA_LOCAL]);
630 ifa->ifa_address = nla_get_be32(tb[IFA_ADDRESS]);
631
632 if (tb[IFA_BROADCAST])
633 ifa->ifa_broadcast = nla_get_be32(tb[IFA_BROADCAST]);
634
635 if (tb[IFA_LABEL])
636 nla_strlcpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ);
637 else
638 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
639
640 return ifa;
641
642 errout:
643 return ERR_PTR(err);
644 }
645
inet_rtm_newaddr(struct sk_buff * skb,struct nlmsghdr * nlh,void * arg)646 static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
647 {
648 struct net *net = sock_net(skb->sk);
649 struct in_ifaddr *ifa;
650
651 ASSERT_RTNL();
652
653 ifa = rtm_to_ifaddr(net, nlh);
654 if (IS_ERR(ifa))
655 return PTR_ERR(ifa);
656
657 return __inet_insert_ifa(ifa, nlh, NETLINK_CB(skb).pid);
658 }
659
660 /*
661 * Determine a default network mask, based on the IP address.
662 */
663
inet_abc_len(__be32 addr)664 static inline int inet_abc_len(__be32 addr)
665 {
666 int rc = -1; /* Something else, probably a multicast. */
667
668 if (ipv4_is_zeronet(addr))
669 rc = 0;
670 else {
671 __u32 haddr = ntohl(addr);
672
673 if (IN_CLASSA(haddr))
674 rc = 8;
675 else if (IN_CLASSB(haddr))
676 rc = 16;
677 else if (IN_CLASSC(haddr))
678 rc = 24;
679 }
680
681 return rc;
682 }
683
684
devinet_ioctl(struct net * net,unsigned int cmd,void __user * arg)685 int devinet_ioctl(struct net *net, unsigned int cmd, void __user *arg)
686 {
687 struct ifreq ifr;
688 struct sockaddr_in sin_orig;
689 struct sockaddr_in *sin = (struct sockaddr_in *)&ifr.ifr_addr;
690 struct in_device *in_dev;
691 struct in_ifaddr **ifap = NULL;
692 struct in_ifaddr *ifa = NULL;
693 struct net_device *dev;
694 char *colon;
695 int ret = -EFAULT;
696 int tryaddrmatch = 0;
697
698 /*
699 * Fetch the caller's info block into kernel space
700 */
701
702 if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
703 goto out;
704 ifr.ifr_name[IFNAMSIZ - 1] = 0;
705
706 /* save original address for comparison */
707 memcpy(&sin_orig, sin, sizeof(*sin));
708
709 colon = strchr(ifr.ifr_name, ':');
710 if (colon)
711 *colon = 0;
712
713 dev_load(net, ifr.ifr_name);
714
715 switch (cmd) {
716 case SIOCGIFADDR: /* Get interface address */
717 case SIOCGIFBRDADDR: /* Get the broadcast address */
718 case SIOCGIFDSTADDR: /* Get the destination address */
719 case SIOCGIFNETMASK: /* Get the netmask for the interface */
720 /* Note that these ioctls will not sleep,
721 so that we do not impose a lock.
722 One day we will be forced to put shlock here (I mean SMP)
723 */
724 tryaddrmatch = (sin_orig.sin_family == AF_INET);
725 memset(sin, 0, sizeof(*sin));
726 sin->sin_family = AF_INET;
727 break;
728
729 case SIOCSIFFLAGS:
730 ret = -EACCES;
731 if (!capable(CAP_NET_ADMIN))
732 goto out;
733 break;
734 case SIOCSIFADDR: /* Set interface address (and family) */
735 case SIOCSIFBRDADDR: /* Set the broadcast address */
736 case SIOCSIFDSTADDR: /* Set the destination address */
737 case SIOCSIFNETMASK: /* Set the netmask for the interface */
738 ret = -EACCES;
739 if (!capable(CAP_NET_ADMIN))
740 goto out;
741 ret = -EINVAL;
742 if (sin->sin_family != AF_INET)
743 goto out;
744 break;
745 default:
746 ret = -EINVAL;
747 goto out;
748 }
749
750 rtnl_lock();
751
752 ret = -ENODEV;
753 dev = __dev_get_by_name(net, ifr.ifr_name);
754 if (!dev)
755 goto done;
756
757 if (colon)
758 *colon = ':';
759
760 in_dev = __in_dev_get_rtnl(dev);
761 if (in_dev) {
762 if (tryaddrmatch) {
763 /* Matthias Andree */
764 /* compare label and address (4.4BSD style) */
765 /* note: we only do this for a limited set of ioctls
766 and only if the original address family was AF_INET.
767 This is checked above. */
768 for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
769 ifap = &ifa->ifa_next) {
770 if (!strcmp(ifr.ifr_name, ifa->ifa_label) &&
771 sin_orig.sin_addr.s_addr ==
772 ifa->ifa_local) {
773 break; /* found */
774 }
775 }
776 }
777 /* we didn't get a match, maybe the application is
778 4.3BSD-style and passed in junk so we fall back to
779 comparing just the label */
780 if (!ifa) {
781 for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
782 ifap = &ifa->ifa_next)
783 if (!strcmp(ifr.ifr_name, ifa->ifa_label))
784 break;
785 }
786 }
787
788 ret = -EADDRNOTAVAIL;
789 if (!ifa && cmd != SIOCSIFADDR && cmd != SIOCSIFFLAGS)
790 goto done;
791
792 switch (cmd) {
793 case SIOCGIFADDR: /* Get interface address */
794 sin->sin_addr.s_addr = ifa->ifa_local;
795 goto rarok;
796
797 case SIOCGIFBRDADDR: /* Get the broadcast address */
798 sin->sin_addr.s_addr = ifa->ifa_broadcast;
799 goto rarok;
800
801 case SIOCGIFDSTADDR: /* Get the destination address */
802 sin->sin_addr.s_addr = ifa->ifa_address;
803 goto rarok;
804
805 case SIOCGIFNETMASK: /* Get the netmask for the interface */
806 sin->sin_addr.s_addr = ifa->ifa_mask;
807 goto rarok;
808
809 case SIOCSIFFLAGS:
810 if (colon) {
811 ret = -EADDRNOTAVAIL;
812 if (!ifa)
813 break;
814 ret = 0;
815 if (!(ifr.ifr_flags & IFF_UP))
816 inet_del_ifa(in_dev, ifap, 1);
817 break;
818 }
819 ret = dev_change_flags(dev, ifr.ifr_flags);
820 break;
821
822 case SIOCSIFADDR: /* Set interface address (and family) */
823 ret = -EINVAL;
824 if (inet_abc_len(sin->sin_addr.s_addr) < 0)
825 break;
826
827 if (!ifa) {
828 ret = -ENOBUFS;
829 ifa = inet_alloc_ifa();
830 INIT_HLIST_NODE(&ifa->hash);
831 if (!ifa)
832 break;
833 if (colon)
834 memcpy(ifa->ifa_label, ifr.ifr_name, IFNAMSIZ);
835 else
836 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
837 } else {
838 ret = 0;
839 if (ifa->ifa_local == sin->sin_addr.s_addr)
840 break;
841 inet_del_ifa(in_dev, ifap, 0);
842 ifa->ifa_broadcast = 0;
843 ifa->ifa_scope = 0;
844 }
845
846 ifa->ifa_address = ifa->ifa_local = sin->sin_addr.s_addr;
847
848 if (!(dev->flags & IFF_POINTOPOINT)) {
849 ifa->ifa_prefixlen = inet_abc_len(ifa->ifa_address);
850 ifa->ifa_mask = inet_make_mask(ifa->ifa_prefixlen);
851 if ((dev->flags & IFF_BROADCAST) &&
852 ifa->ifa_prefixlen < 31)
853 ifa->ifa_broadcast = ifa->ifa_address |
854 ~ifa->ifa_mask;
855 } else {
856 ifa->ifa_prefixlen = 32;
857 ifa->ifa_mask = inet_make_mask(32);
858 }
859 ret = inet_set_ifa(dev, ifa);
860 break;
861
862 case SIOCSIFBRDADDR: /* Set the broadcast address */
863 ret = 0;
864 if (ifa->ifa_broadcast != sin->sin_addr.s_addr) {
865 inet_del_ifa(in_dev, ifap, 0);
866 ifa->ifa_broadcast = sin->sin_addr.s_addr;
867 inet_insert_ifa(ifa);
868 }
869 break;
870
871 case SIOCSIFDSTADDR: /* Set the destination address */
872 ret = 0;
873 if (ifa->ifa_address == sin->sin_addr.s_addr)
874 break;
875 ret = -EINVAL;
876 if (inet_abc_len(sin->sin_addr.s_addr) < 0)
877 break;
878 ret = 0;
879 inet_del_ifa(in_dev, ifap, 0);
880 ifa->ifa_address = sin->sin_addr.s_addr;
881 inet_insert_ifa(ifa);
882 break;
883
884 case SIOCSIFNETMASK: /* Set the netmask for the interface */
885
886 /*
887 * The mask we set must be legal.
888 */
889 ret = -EINVAL;
890 if (bad_mask(sin->sin_addr.s_addr, 0))
891 break;
892 ret = 0;
893 if (ifa->ifa_mask != sin->sin_addr.s_addr) {
894 __be32 old_mask = ifa->ifa_mask;
895 inet_del_ifa(in_dev, ifap, 0);
896 ifa->ifa_mask = sin->sin_addr.s_addr;
897 ifa->ifa_prefixlen = inet_mask_len(ifa->ifa_mask);
898
899 /* See if current broadcast address matches
900 * with current netmask, then recalculate
901 * the broadcast address. Otherwise it's a
902 * funny address, so don't touch it since
903 * the user seems to know what (s)he's doing...
904 */
905 if ((dev->flags & IFF_BROADCAST) &&
906 (ifa->ifa_prefixlen < 31) &&
907 (ifa->ifa_broadcast ==
908 (ifa->ifa_local|~old_mask))) {
909 ifa->ifa_broadcast = (ifa->ifa_local |
910 ~sin->sin_addr.s_addr);
911 }
912 inet_insert_ifa(ifa);
913 }
914 break;
915 }
916 done:
917 rtnl_unlock();
918 out:
919 return ret;
920 rarok:
921 rtnl_unlock();
922 ret = copy_to_user(arg, &ifr, sizeof(struct ifreq)) ? -EFAULT : 0;
923 goto out;
924 }
925
inet_gifconf(struct net_device * dev,char __user * buf,int len)926 static int inet_gifconf(struct net_device *dev, char __user *buf, int len)
927 {
928 struct in_device *in_dev = __in_dev_get_rtnl(dev);
929 struct in_ifaddr *ifa;
930 struct ifreq ifr;
931 int done = 0;
932
933 if (!in_dev)
934 goto out;
935
936 for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
937 if (!buf) {
938 done += sizeof(ifr);
939 continue;
940 }
941 if (len < (int) sizeof(ifr))
942 break;
943 memset(&ifr, 0, sizeof(struct ifreq));
944 if (ifa->ifa_label)
945 strcpy(ifr.ifr_name, ifa->ifa_label);
946 else
947 strcpy(ifr.ifr_name, dev->name);
948
949 (*(struct sockaddr_in *)&ifr.ifr_addr).sin_family = AF_INET;
950 (*(struct sockaddr_in *)&ifr.ifr_addr).sin_addr.s_addr =
951 ifa->ifa_local;
952
953 if (copy_to_user(buf, &ifr, sizeof(struct ifreq))) {
954 done = -EFAULT;
955 break;
956 }
957 buf += sizeof(struct ifreq);
958 len -= sizeof(struct ifreq);
959 done += sizeof(struct ifreq);
960 }
961 out:
962 return done;
963 }
964
inet_select_addr(const struct net_device * dev,__be32 dst,int scope)965 __be32 inet_select_addr(const struct net_device *dev, __be32 dst, int scope)
966 {
967 __be32 addr = 0;
968 struct in_device *in_dev;
969 struct net *net = dev_net(dev);
970
971 rcu_read_lock();
972 in_dev = __in_dev_get_rcu(dev);
973 if (!in_dev)
974 goto no_in_dev;
975
976 for_primary_ifa(in_dev) {
977 if (ifa->ifa_scope > scope)
978 continue;
979 if (!dst || inet_ifa_match(dst, ifa)) {
980 addr = ifa->ifa_local;
981 break;
982 }
983 if (!addr)
984 addr = ifa->ifa_local;
985 } endfor_ifa(in_dev);
986
987 if (addr)
988 goto out_unlock;
989 no_in_dev:
990
991 /* Not loopback addresses on loopback should be preferred
992 in this case. It is importnat that lo is the first interface
993 in dev_base list.
994 */
995 for_each_netdev_rcu(net, dev) {
996 in_dev = __in_dev_get_rcu(dev);
997 if (!in_dev)
998 continue;
999
1000 for_primary_ifa(in_dev) {
1001 if (ifa->ifa_scope != RT_SCOPE_LINK &&
1002 ifa->ifa_scope <= scope) {
1003 addr = ifa->ifa_local;
1004 goto out_unlock;
1005 }
1006 } endfor_ifa(in_dev);
1007 }
1008 out_unlock:
1009 rcu_read_unlock();
1010 return addr;
1011 }
1012 EXPORT_SYMBOL(inet_select_addr);
1013
confirm_addr_indev(struct in_device * in_dev,__be32 dst,__be32 local,int scope)1014 static __be32 confirm_addr_indev(struct in_device *in_dev, __be32 dst,
1015 __be32 local, int scope)
1016 {
1017 int same = 0;
1018 __be32 addr = 0;
1019
1020 for_ifa(in_dev) {
1021 if (!addr &&
1022 (local == ifa->ifa_local || !local) &&
1023 ifa->ifa_scope <= scope) {
1024 addr = ifa->ifa_local;
1025 if (same)
1026 break;
1027 }
1028 if (!same) {
1029 same = (!local || inet_ifa_match(local, ifa)) &&
1030 (!dst || inet_ifa_match(dst, ifa));
1031 if (same && addr) {
1032 if (local || !dst)
1033 break;
1034 /* Is the selected addr into dst subnet? */
1035 if (inet_ifa_match(addr, ifa))
1036 break;
1037 /* No, then can we use new local src? */
1038 if (ifa->ifa_scope <= scope) {
1039 addr = ifa->ifa_local;
1040 break;
1041 }
1042 /* search for large dst subnet for addr */
1043 same = 0;
1044 }
1045 }
1046 } endfor_ifa(in_dev);
1047
1048 return same ? addr : 0;
1049 }
1050
1051 /*
1052 * Confirm that local IP address exists using wildcards:
1053 * - in_dev: only on this interface, 0=any interface
1054 * - dst: only in the same subnet as dst, 0=any dst
1055 * - local: address, 0=autoselect the local address
1056 * - scope: maximum allowed scope value for the local address
1057 */
inet_confirm_addr(struct in_device * in_dev,__be32 dst,__be32 local,int scope)1058 __be32 inet_confirm_addr(struct in_device *in_dev,
1059 __be32 dst, __be32 local, int scope)
1060 {
1061 __be32 addr = 0;
1062 struct net_device *dev;
1063 struct net *net;
1064
1065 if (scope != RT_SCOPE_LINK)
1066 return confirm_addr_indev(in_dev, dst, local, scope);
1067
1068 net = dev_net(in_dev->dev);
1069 rcu_read_lock();
1070 for_each_netdev_rcu(net, dev) {
1071 in_dev = __in_dev_get_rcu(dev);
1072 if (in_dev) {
1073 addr = confirm_addr_indev(in_dev, dst, local, scope);
1074 if (addr)
1075 break;
1076 }
1077 }
1078 rcu_read_unlock();
1079
1080 return addr;
1081 }
1082
1083 /*
1084 * Device notifier
1085 */
1086
register_inetaddr_notifier(struct notifier_block * nb)1087 int register_inetaddr_notifier(struct notifier_block *nb)
1088 {
1089 return blocking_notifier_chain_register(&inetaddr_chain, nb);
1090 }
1091 EXPORT_SYMBOL(register_inetaddr_notifier);
1092
unregister_inetaddr_notifier(struct notifier_block * nb)1093 int unregister_inetaddr_notifier(struct notifier_block *nb)
1094 {
1095 return blocking_notifier_chain_unregister(&inetaddr_chain, nb);
1096 }
1097 EXPORT_SYMBOL(unregister_inetaddr_notifier);
1098
1099 /* Rename ifa_labels for a device name change. Make some effort to preserve
1100 * existing alias numbering and to create unique labels if possible.
1101 */
inetdev_changename(struct net_device * dev,struct in_device * in_dev)1102 static void inetdev_changename(struct net_device *dev, struct in_device *in_dev)
1103 {
1104 struct in_ifaddr *ifa;
1105 int named = 0;
1106
1107 for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
1108 char old[IFNAMSIZ], *dot;
1109
1110 memcpy(old, ifa->ifa_label, IFNAMSIZ);
1111 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1112 if (named++ == 0)
1113 goto skip;
1114 dot = strchr(old, ':');
1115 if (dot == NULL) {
1116 sprintf(old, ":%d", named);
1117 dot = old;
1118 }
1119 if (strlen(dot) + strlen(dev->name) < IFNAMSIZ)
1120 strcat(ifa->ifa_label, dot);
1121 else
1122 strcpy(ifa->ifa_label + (IFNAMSIZ - strlen(dot) - 1), dot);
1123 skip:
1124 rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0);
1125 }
1126 }
1127
inetdev_valid_mtu(unsigned mtu)1128 static inline bool inetdev_valid_mtu(unsigned mtu)
1129 {
1130 return mtu >= 68;
1131 }
1132
inetdev_send_gratuitous_arp(struct net_device * dev,struct in_device * in_dev)1133 static void inetdev_send_gratuitous_arp(struct net_device *dev,
1134 struct in_device *in_dev)
1135
1136 {
1137 struct in_ifaddr *ifa = in_dev->ifa_list;
1138
1139 if (!ifa)
1140 return;
1141
1142 arp_send(ARPOP_REQUEST, ETH_P_ARP,
1143 ifa->ifa_local, dev,
1144 ifa->ifa_local, NULL,
1145 dev->dev_addr, NULL);
1146 }
1147
1148 /* Called only under RTNL semaphore */
1149
inetdev_event(struct notifier_block * this,unsigned long event,void * ptr)1150 static int inetdev_event(struct notifier_block *this, unsigned long event,
1151 void *ptr)
1152 {
1153 struct net_device *dev = ptr;
1154 struct in_device *in_dev = __in_dev_get_rtnl(dev);
1155
1156 ASSERT_RTNL();
1157
1158 if (!in_dev) {
1159 if (event == NETDEV_REGISTER) {
1160 in_dev = inetdev_init(dev);
1161 if (!in_dev)
1162 return notifier_from_errno(-ENOMEM);
1163 if (dev->flags & IFF_LOOPBACK) {
1164 IN_DEV_CONF_SET(in_dev, NOXFRM, 1);
1165 IN_DEV_CONF_SET(in_dev, NOPOLICY, 1);
1166 }
1167 } else if (event == NETDEV_CHANGEMTU) {
1168 /* Re-enabling IP */
1169 if (inetdev_valid_mtu(dev->mtu))
1170 in_dev = inetdev_init(dev);
1171 }
1172 goto out;
1173 }
1174
1175 switch (event) {
1176 case NETDEV_REGISTER:
1177 printk(KERN_DEBUG "inetdev_event: bug\n");
1178 rcu_assign_pointer(dev->ip_ptr, NULL);
1179 break;
1180 case NETDEV_UP:
1181 if (!inetdev_valid_mtu(dev->mtu))
1182 break;
1183 if (dev->flags & IFF_LOOPBACK) {
1184 struct in_ifaddr *ifa = inet_alloc_ifa();
1185
1186 if (ifa) {
1187 INIT_HLIST_NODE(&ifa->hash);
1188 ifa->ifa_local =
1189 ifa->ifa_address = htonl(INADDR_LOOPBACK);
1190 ifa->ifa_prefixlen = 8;
1191 ifa->ifa_mask = inet_make_mask(8);
1192 in_dev_hold(in_dev);
1193 ifa->ifa_dev = in_dev;
1194 ifa->ifa_scope = RT_SCOPE_HOST;
1195 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1196 inet_insert_ifa(ifa);
1197 }
1198 }
1199 ip_mc_up(in_dev);
1200 /* fall through */
1201 case NETDEV_CHANGEADDR:
1202 if (!IN_DEV_ARP_NOTIFY(in_dev))
1203 break;
1204 /* fall through */
1205 case NETDEV_NOTIFY_PEERS:
1206 /* Send gratuitous ARP to notify of link change */
1207 inetdev_send_gratuitous_arp(dev, in_dev);
1208 break;
1209 case NETDEV_DOWN:
1210 ip_mc_down(in_dev);
1211 break;
1212 case NETDEV_PRE_TYPE_CHANGE:
1213 ip_mc_unmap(in_dev);
1214 break;
1215 case NETDEV_POST_TYPE_CHANGE:
1216 ip_mc_remap(in_dev);
1217 break;
1218 case NETDEV_CHANGEMTU:
1219 if (inetdev_valid_mtu(dev->mtu))
1220 break;
1221 /* disable IP when MTU is not enough */
1222 case NETDEV_UNREGISTER:
1223 inetdev_destroy(in_dev);
1224 break;
1225 case NETDEV_CHANGENAME:
1226 /* Do not notify about label change, this event is
1227 * not interesting to applications using netlink.
1228 */
1229 inetdev_changename(dev, in_dev);
1230
1231 devinet_sysctl_unregister(in_dev);
1232 devinet_sysctl_register(in_dev);
1233 break;
1234 }
1235 out:
1236 return NOTIFY_DONE;
1237 }
1238
1239 static struct notifier_block ip_netdev_notifier = {
1240 .notifier_call = inetdev_event,
1241 };
1242
inet_nlmsg_size(void)1243 static inline size_t inet_nlmsg_size(void)
1244 {
1245 return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
1246 + nla_total_size(4) /* IFA_ADDRESS */
1247 + nla_total_size(4) /* IFA_LOCAL */
1248 + nla_total_size(4) /* IFA_BROADCAST */
1249 + nla_total_size(IFNAMSIZ); /* IFA_LABEL */
1250 }
1251
inet_fill_ifaddr(struct sk_buff * skb,struct in_ifaddr * ifa,u32 pid,u32 seq,int event,unsigned int flags)1252 static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa,
1253 u32 pid, u32 seq, int event, unsigned int flags)
1254 {
1255 struct ifaddrmsg *ifm;
1256 struct nlmsghdr *nlh;
1257
1258 nlh = nlmsg_put(skb, pid, seq, event, sizeof(*ifm), flags);
1259 if (nlh == NULL)
1260 return -EMSGSIZE;
1261
1262 ifm = nlmsg_data(nlh);
1263 ifm->ifa_family = AF_INET;
1264 ifm->ifa_prefixlen = ifa->ifa_prefixlen;
1265 ifm->ifa_flags = ifa->ifa_flags|IFA_F_PERMANENT;
1266 ifm->ifa_scope = ifa->ifa_scope;
1267 ifm->ifa_index = ifa->ifa_dev->dev->ifindex;
1268
1269 if (ifa->ifa_address)
1270 NLA_PUT_BE32(skb, IFA_ADDRESS, ifa->ifa_address);
1271
1272 if (ifa->ifa_local)
1273 NLA_PUT_BE32(skb, IFA_LOCAL, ifa->ifa_local);
1274
1275 if (ifa->ifa_broadcast)
1276 NLA_PUT_BE32(skb, IFA_BROADCAST, ifa->ifa_broadcast);
1277
1278 if (ifa->ifa_label[0])
1279 NLA_PUT_STRING(skb, IFA_LABEL, ifa->ifa_label);
1280
1281 return nlmsg_end(skb, nlh);
1282
1283 nla_put_failure:
1284 nlmsg_cancel(skb, nlh);
1285 return -EMSGSIZE;
1286 }
1287
inet_dump_ifaddr(struct sk_buff * skb,struct netlink_callback * cb)1288 static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
1289 {
1290 struct net *net = sock_net(skb->sk);
1291 int h, s_h;
1292 int idx, s_idx;
1293 int ip_idx, s_ip_idx;
1294 struct net_device *dev;
1295 struct in_device *in_dev;
1296 struct in_ifaddr *ifa;
1297 struct hlist_head *head;
1298 struct hlist_node *node;
1299
1300 s_h = cb->args[0];
1301 s_idx = idx = cb->args[1];
1302 s_ip_idx = ip_idx = cb->args[2];
1303
1304 for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
1305 idx = 0;
1306 head = &net->dev_index_head[h];
1307 rcu_read_lock();
1308 hlist_for_each_entry_rcu(dev, node, head, index_hlist) {
1309 if (idx < s_idx)
1310 goto cont;
1311 if (h > s_h || idx > s_idx)
1312 s_ip_idx = 0;
1313 in_dev = __in_dev_get_rcu(dev);
1314 if (!in_dev)
1315 goto cont;
1316
1317 for (ifa = in_dev->ifa_list, ip_idx = 0; ifa;
1318 ifa = ifa->ifa_next, ip_idx++) {
1319 if (ip_idx < s_ip_idx)
1320 continue;
1321 if (inet_fill_ifaddr(skb, ifa,
1322 NETLINK_CB(cb->skb).pid,
1323 cb->nlh->nlmsg_seq,
1324 RTM_NEWADDR, NLM_F_MULTI) <= 0) {
1325 rcu_read_unlock();
1326 goto done;
1327 }
1328 }
1329 cont:
1330 idx++;
1331 }
1332 rcu_read_unlock();
1333 }
1334
1335 done:
1336 cb->args[0] = h;
1337 cb->args[1] = idx;
1338 cb->args[2] = ip_idx;
1339
1340 return skb->len;
1341 }
1342
rtmsg_ifa(int event,struct in_ifaddr * ifa,struct nlmsghdr * nlh,u32 pid)1343 static void rtmsg_ifa(int event, struct in_ifaddr *ifa, struct nlmsghdr *nlh,
1344 u32 pid)
1345 {
1346 struct sk_buff *skb;
1347 u32 seq = nlh ? nlh->nlmsg_seq : 0;
1348 int err = -ENOBUFS;
1349 struct net *net;
1350
1351 net = dev_net(ifa->ifa_dev->dev);
1352 skb = nlmsg_new(inet_nlmsg_size(), GFP_KERNEL);
1353 if (skb == NULL)
1354 goto errout;
1355
1356 err = inet_fill_ifaddr(skb, ifa, pid, seq, event, 0);
1357 if (err < 0) {
1358 /* -EMSGSIZE implies BUG in inet_nlmsg_size() */
1359 WARN_ON(err == -EMSGSIZE);
1360 kfree_skb(skb);
1361 goto errout;
1362 }
1363 rtnl_notify(skb, net, pid, RTNLGRP_IPV4_IFADDR, nlh, GFP_KERNEL);
1364 return;
1365 errout:
1366 if (err < 0)
1367 rtnl_set_sk_err(net, RTNLGRP_IPV4_IFADDR, err);
1368 }
1369
inet_get_link_af_size(const struct net_device * dev)1370 static size_t inet_get_link_af_size(const struct net_device *dev)
1371 {
1372 struct in_device *in_dev = __in_dev_get_rtnl(dev);
1373
1374 if (!in_dev)
1375 return 0;
1376
1377 return nla_total_size(IPV4_DEVCONF_MAX * 4); /* IFLA_INET_CONF */
1378 }
1379
inet_fill_link_af(struct sk_buff * skb,const struct net_device * dev)1380 static int inet_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
1381 {
1382 struct in_device *in_dev = __in_dev_get_rtnl(dev);
1383 struct nlattr *nla;
1384 int i;
1385
1386 if (!in_dev)
1387 return -ENODATA;
1388
1389 nla = nla_reserve(skb, IFLA_INET_CONF, IPV4_DEVCONF_MAX * 4);
1390 if (nla == NULL)
1391 return -EMSGSIZE;
1392
1393 for (i = 0; i < IPV4_DEVCONF_MAX; i++)
1394 ((u32 *) nla_data(nla))[i] = in_dev->cnf.data[i];
1395
1396 return 0;
1397 }
1398
1399 static const struct nla_policy inet_af_policy[IFLA_INET_MAX+1] = {
1400 [IFLA_INET_CONF] = { .type = NLA_NESTED },
1401 };
1402
inet_validate_link_af(const struct net_device * dev,const struct nlattr * nla)1403 static int inet_validate_link_af(const struct net_device *dev,
1404 const struct nlattr *nla)
1405 {
1406 struct nlattr *a, *tb[IFLA_INET_MAX+1];
1407 int err, rem;
1408
1409 if (dev && !__in_dev_get_rtnl(dev))
1410 return -EAFNOSUPPORT;
1411
1412 err = nla_parse_nested(tb, IFLA_INET_MAX, nla, inet_af_policy);
1413 if (err < 0)
1414 return err;
1415
1416 if (tb[IFLA_INET_CONF]) {
1417 nla_for_each_nested(a, tb[IFLA_INET_CONF], rem) {
1418 int cfgid = nla_type(a);
1419
1420 if (nla_len(a) < 4)
1421 return -EINVAL;
1422
1423 if (cfgid <= 0 || cfgid > IPV4_DEVCONF_MAX)
1424 return -EINVAL;
1425 }
1426 }
1427
1428 return 0;
1429 }
1430
inet_set_link_af(struct net_device * dev,const struct nlattr * nla)1431 static int inet_set_link_af(struct net_device *dev, const struct nlattr *nla)
1432 {
1433 struct in_device *in_dev = __in_dev_get_rtnl(dev);
1434 struct nlattr *a, *tb[IFLA_INET_MAX+1];
1435 int rem;
1436
1437 if (!in_dev)
1438 return -EAFNOSUPPORT;
1439
1440 if (nla_parse_nested(tb, IFLA_INET_MAX, nla, NULL) < 0)
1441 BUG();
1442
1443 if (tb[IFLA_INET_CONF]) {
1444 nla_for_each_nested(a, tb[IFLA_INET_CONF], rem)
1445 ipv4_devconf_set(in_dev, nla_type(a), nla_get_u32(a));
1446 }
1447
1448 return 0;
1449 }
1450
1451 #ifdef CONFIG_SYSCTL
1452
devinet_copy_dflt_conf(struct net * net,int i)1453 static void devinet_copy_dflt_conf(struct net *net, int i)
1454 {
1455 struct net_device *dev;
1456
1457 rcu_read_lock();
1458 for_each_netdev_rcu(net, dev) {
1459 struct in_device *in_dev;
1460
1461 in_dev = __in_dev_get_rcu(dev);
1462 if (in_dev && !test_bit(i, in_dev->cnf.state))
1463 in_dev->cnf.data[i] = net->ipv4.devconf_dflt->data[i];
1464 }
1465 rcu_read_unlock();
1466 }
1467
1468 /* called with RTNL locked */
inet_forward_change(struct net * net)1469 static void inet_forward_change(struct net *net)
1470 {
1471 struct net_device *dev;
1472 int on = IPV4_DEVCONF_ALL(net, FORWARDING);
1473
1474 IPV4_DEVCONF_ALL(net, ACCEPT_REDIRECTS) = !on;
1475 IPV4_DEVCONF_DFLT(net, FORWARDING) = on;
1476
1477 for_each_netdev(net, dev) {
1478 struct in_device *in_dev;
1479 if (on)
1480 dev_disable_lro(dev);
1481 rcu_read_lock();
1482 in_dev = __in_dev_get_rcu(dev);
1483 if (in_dev)
1484 IN_DEV_CONF_SET(in_dev, FORWARDING, on);
1485 rcu_read_unlock();
1486 }
1487 }
1488
devinet_conf_proc(ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)1489 static int devinet_conf_proc(ctl_table *ctl, int write,
1490 void __user *buffer,
1491 size_t *lenp, loff_t *ppos)
1492 {
1493 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
1494
1495 if (write) {
1496 struct ipv4_devconf *cnf = ctl->extra1;
1497 struct net *net = ctl->extra2;
1498 int i = (int *)ctl->data - cnf->data;
1499
1500 set_bit(i, cnf->state);
1501
1502 if (cnf == net->ipv4.devconf_dflt)
1503 devinet_copy_dflt_conf(net, i);
1504 }
1505
1506 return ret;
1507 }
1508
devinet_sysctl_forward(ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)1509 static int devinet_sysctl_forward(ctl_table *ctl, int write,
1510 void __user *buffer,
1511 size_t *lenp, loff_t *ppos)
1512 {
1513 int *valp = ctl->data;
1514 int val = *valp;
1515 loff_t pos = *ppos;
1516 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
1517
1518 if (write && *valp != val) {
1519 struct net *net = ctl->extra2;
1520
1521 if (valp != &IPV4_DEVCONF_DFLT(net, FORWARDING)) {
1522 if (!rtnl_trylock()) {
1523 /* Restore the original values before restarting */
1524 *valp = val;
1525 *ppos = pos;
1526 return restart_syscall();
1527 }
1528 if (valp == &IPV4_DEVCONF_ALL(net, FORWARDING)) {
1529 inet_forward_change(net);
1530 } else if (*valp) {
1531 struct ipv4_devconf *cnf = ctl->extra1;
1532 struct in_device *idev =
1533 container_of(cnf, struct in_device, cnf);
1534 dev_disable_lro(idev->dev);
1535 }
1536 rtnl_unlock();
1537 rt_cache_flush(net, 0);
1538 }
1539 }
1540
1541 return ret;
1542 }
1543
ipv4_doint_and_flush(ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)1544 static int ipv4_doint_and_flush(ctl_table *ctl, int write,
1545 void __user *buffer,
1546 size_t *lenp, loff_t *ppos)
1547 {
1548 int *valp = ctl->data;
1549 int val = *valp;
1550 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
1551 struct net *net = ctl->extra2;
1552
1553 if (write && *valp != val)
1554 rt_cache_flush(net, 0);
1555
1556 return ret;
1557 }
1558
1559 #define DEVINET_SYSCTL_ENTRY(attr, name, mval, proc) \
1560 { \
1561 .procname = name, \
1562 .data = ipv4_devconf.data + \
1563 IPV4_DEVCONF_ ## attr - 1, \
1564 .maxlen = sizeof(int), \
1565 .mode = mval, \
1566 .proc_handler = proc, \
1567 .extra1 = &ipv4_devconf, \
1568 }
1569
1570 #define DEVINET_SYSCTL_RW_ENTRY(attr, name) \
1571 DEVINET_SYSCTL_ENTRY(attr, name, 0644, devinet_conf_proc)
1572
1573 #define DEVINET_SYSCTL_RO_ENTRY(attr, name) \
1574 DEVINET_SYSCTL_ENTRY(attr, name, 0444, devinet_conf_proc)
1575
1576 #define DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, proc) \
1577 DEVINET_SYSCTL_ENTRY(attr, name, 0644, proc)
1578
1579 #define DEVINET_SYSCTL_FLUSHING_ENTRY(attr, name) \
1580 DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, ipv4_doint_and_flush)
1581
1582 static struct devinet_sysctl_table {
1583 struct ctl_table_header *sysctl_header;
1584 struct ctl_table devinet_vars[__IPV4_DEVCONF_MAX];
1585 char *dev_name;
1586 } devinet_sysctl = {
1587 .devinet_vars = {
1588 DEVINET_SYSCTL_COMPLEX_ENTRY(FORWARDING, "forwarding",
1589 devinet_sysctl_forward),
1590 DEVINET_SYSCTL_RO_ENTRY(MC_FORWARDING, "mc_forwarding"),
1591
1592 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_REDIRECTS, "accept_redirects"),
1593 DEVINET_SYSCTL_RW_ENTRY(SECURE_REDIRECTS, "secure_redirects"),
1594 DEVINET_SYSCTL_RW_ENTRY(SHARED_MEDIA, "shared_media"),
1595 DEVINET_SYSCTL_RW_ENTRY(RP_FILTER, "rp_filter"),
1596 DEVINET_SYSCTL_RW_ENTRY(SEND_REDIRECTS, "send_redirects"),
1597 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_SOURCE_ROUTE,
1598 "accept_source_route"),
1599 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_LOCAL, "accept_local"),
1600 DEVINET_SYSCTL_RW_ENTRY(SRC_VMARK, "src_valid_mark"),
1601 DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP, "proxy_arp"),
1602 DEVINET_SYSCTL_RW_ENTRY(MEDIUM_ID, "medium_id"),
1603 DEVINET_SYSCTL_RW_ENTRY(BOOTP_RELAY, "bootp_relay"),
1604 DEVINET_SYSCTL_RW_ENTRY(LOG_MARTIANS, "log_martians"),
1605 DEVINET_SYSCTL_RW_ENTRY(TAG, "tag"),
1606 DEVINET_SYSCTL_RW_ENTRY(ARPFILTER, "arp_filter"),
1607 DEVINET_SYSCTL_RW_ENTRY(ARP_ANNOUNCE, "arp_announce"),
1608 DEVINET_SYSCTL_RW_ENTRY(ARP_IGNORE, "arp_ignore"),
1609 DEVINET_SYSCTL_RW_ENTRY(ARP_ACCEPT, "arp_accept"),
1610 DEVINET_SYSCTL_RW_ENTRY(ARP_NOTIFY, "arp_notify"),
1611 DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP_PVLAN, "proxy_arp_pvlan"),
1612
1613 DEVINET_SYSCTL_FLUSHING_ENTRY(NOXFRM, "disable_xfrm"),
1614 DEVINET_SYSCTL_FLUSHING_ENTRY(NOPOLICY, "disable_policy"),
1615 DEVINET_SYSCTL_FLUSHING_ENTRY(FORCE_IGMP_VERSION,
1616 "force_igmp_version"),
1617 DEVINET_SYSCTL_FLUSHING_ENTRY(PROMOTE_SECONDARIES,
1618 "promote_secondaries"),
1619 },
1620 };
1621
__devinet_sysctl_register(struct net * net,char * dev_name,struct ipv4_devconf * p)1622 static int __devinet_sysctl_register(struct net *net, char *dev_name,
1623 struct ipv4_devconf *p)
1624 {
1625 int i;
1626 struct devinet_sysctl_table *t;
1627
1628 #define DEVINET_CTL_PATH_DEV 3
1629
1630 struct ctl_path devinet_ctl_path[] = {
1631 { .procname = "net", },
1632 { .procname = "ipv4", },
1633 { .procname = "conf", },
1634 { /* to be set */ },
1635 { },
1636 };
1637
1638 t = kmemdup(&devinet_sysctl, sizeof(*t), GFP_KERNEL);
1639 if (!t)
1640 goto out;
1641
1642 for (i = 0; i < ARRAY_SIZE(t->devinet_vars) - 1; i++) {
1643 t->devinet_vars[i].data += (char *)p - (char *)&ipv4_devconf;
1644 t->devinet_vars[i].extra1 = p;
1645 t->devinet_vars[i].extra2 = net;
1646 }
1647
1648 /*
1649 * Make a copy of dev_name, because '.procname' is regarded as const
1650 * by sysctl and we wouldn't want anyone to change it under our feet
1651 * (see SIOCSIFNAME).
1652 */
1653 t->dev_name = kstrdup(dev_name, GFP_KERNEL);
1654 if (!t->dev_name)
1655 goto free;
1656
1657 devinet_ctl_path[DEVINET_CTL_PATH_DEV].procname = t->dev_name;
1658
1659 t->sysctl_header = register_net_sysctl_table(net, devinet_ctl_path,
1660 t->devinet_vars);
1661 if (!t->sysctl_header)
1662 goto free_procname;
1663
1664 p->sysctl = t;
1665 return 0;
1666
1667 free_procname:
1668 kfree(t->dev_name);
1669 free:
1670 kfree(t);
1671 out:
1672 return -ENOBUFS;
1673 }
1674
__devinet_sysctl_unregister(struct ipv4_devconf * cnf)1675 static void __devinet_sysctl_unregister(struct ipv4_devconf *cnf)
1676 {
1677 struct devinet_sysctl_table *t = cnf->sysctl;
1678
1679 if (t == NULL)
1680 return;
1681
1682 cnf->sysctl = NULL;
1683 unregister_net_sysctl_table(t->sysctl_header);
1684 kfree(t->dev_name);
1685 kfree(t);
1686 }
1687
devinet_sysctl_register(struct in_device * idev)1688 static void devinet_sysctl_register(struct in_device *idev)
1689 {
1690 neigh_sysctl_register(idev->dev, idev->arp_parms, "ipv4", NULL);
1691 __devinet_sysctl_register(dev_net(idev->dev), idev->dev->name,
1692 &idev->cnf);
1693 }
1694
devinet_sysctl_unregister(struct in_device * idev)1695 static void devinet_sysctl_unregister(struct in_device *idev)
1696 {
1697 __devinet_sysctl_unregister(&idev->cnf);
1698 neigh_sysctl_unregister(idev->arp_parms);
1699 }
1700
1701 static struct ctl_table ctl_forward_entry[] = {
1702 {
1703 .procname = "ip_forward",
1704 .data = &ipv4_devconf.data[
1705 IPV4_DEVCONF_FORWARDING - 1],
1706 .maxlen = sizeof(int),
1707 .mode = 0644,
1708 .proc_handler = devinet_sysctl_forward,
1709 .extra1 = &ipv4_devconf,
1710 .extra2 = &init_net,
1711 },
1712 { },
1713 };
1714
1715 static __net_initdata struct ctl_path net_ipv4_path[] = {
1716 { .procname = "net", },
1717 { .procname = "ipv4", },
1718 { },
1719 };
1720 #endif
1721
devinet_init_net(struct net * net)1722 static __net_init int devinet_init_net(struct net *net)
1723 {
1724 int err;
1725 struct ipv4_devconf *all, *dflt;
1726 #ifdef CONFIG_SYSCTL
1727 struct ctl_table *tbl = ctl_forward_entry;
1728 struct ctl_table_header *forw_hdr;
1729 #endif
1730
1731 err = -ENOMEM;
1732 all = &ipv4_devconf;
1733 dflt = &ipv4_devconf_dflt;
1734
1735 if (!net_eq(net, &init_net)) {
1736 all = kmemdup(all, sizeof(ipv4_devconf), GFP_KERNEL);
1737 if (all == NULL)
1738 goto err_alloc_all;
1739
1740 dflt = kmemdup(dflt, sizeof(ipv4_devconf_dflt), GFP_KERNEL);
1741 if (dflt == NULL)
1742 goto err_alloc_dflt;
1743
1744 #ifdef CONFIG_SYSCTL
1745 tbl = kmemdup(tbl, sizeof(ctl_forward_entry), GFP_KERNEL);
1746 if (tbl == NULL)
1747 goto err_alloc_ctl;
1748
1749 tbl[0].data = &all->data[IPV4_DEVCONF_FORWARDING - 1];
1750 tbl[0].extra1 = all;
1751 tbl[0].extra2 = net;
1752 #endif
1753 }
1754
1755 #ifdef CONFIG_SYSCTL
1756 err = __devinet_sysctl_register(net, "all", all);
1757 if (err < 0)
1758 goto err_reg_all;
1759
1760 err = __devinet_sysctl_register(net, "default", dflt);
1761 if (err < 0)
1762 goto err_reg_dflt;
1763
1764 err = -ENOMEM;
1765 forw_hdr = register_net_sysctl_table(net, net_ipv4_path, tbl);
1766 if (forw_hdr == NULL)
1767 goto err_reg_ctl;
1768 net->ipv4.forw_hdr = forw_hdr;
1769 #endif
1770
1771 net->ipv4.devconf_all = all;
1772 net->ipv4.devconf_dflt = dflt;
1773 return 0;
1774
1775 #ifdef CONFIG_SYSCTL
1776 err_reg_ctl:
1777 __devinet_sysctl_unregister(dflt);
1778 err_reg_dflt:
1779 __devinet_sysctl_unregister(all);
1780 err_reg_all:
1781 if (tbl != ctl_forward_entry)
1782 kfree(tbl);
1783 err_alloc_ctl:
1784 #endif
1785 if (dflt != &ipv4_devconf_dflt)
1786 kfree(dflt);
1787 err_alloc_dflt:
1788 if (all != &ipv4_devconf)
1789 kfree(all);
1790 err_alloc_all:
1791 return err;
1792 }
1793
devinet_exit_net(struct net * net)1794 static __net_exit void devinet_exit_net(struct net *net)
1795 {
1796 #ifdef CONFIG_SYSCTL
1797 struct ctl_table *tbl;
1798
1799 tbl = net->ipv4.forw_hdr->ctl_table_arg;
1800 unregister_net_sysctl_table(net->ipv4.forw_hdr);
1801 __devinet_sysctl_unregister(net->ipv4.devconf_dflt);
1802 __devinet_sysctl_unregister(net->ipv4.devconf_all);
1803 kfree(tbl);
1804 #endif
1805 kfree(net->ipv4.devconf_dflt);
1806 kfree(net->ipv4.devconf_all);
1807 }
1808
1809 static __net_initdata struct pernet_operations devinet_ops = {
1810 .init = devinet_init_net,
1811 .exit = devinet_exit_net,
1812 };
1813
1814 static struct rtnl_af_ops inet_af_ops = {
1815 .family = AF_INET,
1816 .fill_link_af = inet_fill_link_af,
1817 .get_link_af_size = inet_get_link_af_size,
1818 .validate_link_af = inet_validate_link_af,
1819 .set_link_af = inet_set_link_af,
1820 };
1821
devinet_init(void)1822 void __init devinet_init(void)
1823 {
1824 int i;
1825
1826 for (i = 0; i < IN4_ADDR_HSIZE; i++)
1827 INIT_HLIST_HEAD(&inet_addr_lst[i]);
1828
1829 register_pernet_subsys(&devinet_ops);
1830
1831 register_gifconf(PF_INET, inet_gifconf);
1832 register_netdevice_notifier(&ip_netdev_notifier);
1833
1834 rtnl_af_register(&inet_af_ops);
1835
1836 rtnl_register(PF_INET, RTM_NEWADDR, inet_rtm_newaddr, NULL);
1837 rtnl_register(PF_INET, RTM_DELADDR, inet_rtm_deladdr, NULL);
1838 rtnl_register(PF_INET, RTM_GETADDR, NULL, inet_dump_ifaddr);
1839 }
1840
1841