1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * NET3 IP device support routines.
4 *
5 * Derived from the IP parts of dev.c 1.0.19
6 * Authors: Ross Biro
7 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
8 * Mark Evans, <evansmp@uhura.aston.ac.uk>
9 *
10 * Additional Authors:
11 * Alan Cox, <gw4pts@gw4pts.ampr.org>
12 * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
13 *
14 * Changes:
15 * Alexey Kuznetsov: pa_* fields are replaced with ifaddr
16 * lists.
17 * Cyrus Durgin: updated for kmod
18 * Matthias Andree: in devinet_ioctl, compare label and
19 * address (4.4BSD alias style support),
20 * fall back to comparing just the label
21 * if no match found.
22 */
23
24
25 #include <linux/uaccess.h>
26 #include <linux/bitops.h>
27 #include <linux/capability.h>
28 #include <linux/module.h>
29 #include <linux/types.h>
30 #include <linux/kernel.h>
31 #include <linux/sched/signal.h>
32 #include <linux/string.h>
33 #include <linux/mm.h>
34 #include <linux/socket.h>
35 #include <linux/sockios.h>
36 #include <linux/in.h>
37 #include <linux/errno.h>
38 #include <linux/interrupt.h>
39 #include <linux/if_addr.h>
40 #include <linux/if_ether.h>
41 #include <linux/inet.h>
42 #include <linux/netdevice.h>
43 #include <linux/etherdevice.h>
44 #include <linux/skbuff.h>
45 #include <linux/init.h>
46 #include <linux/notifier.h>
47 #include <linux/inetdevice.h>
48 #include <linux/igmp.h>
49 #include <linux/slab.h>
50 #include <linux/hash.h>
51 #ifdef CONFIG_SYSCTL
52 #include <linux/sysctl.h>
53 #endif
54 #include <linux/kmod.h>
55 #include <linux/netconf.h>
56
57 #include <net/arp.h>
58 #include <net/ip.h>
59 #include <net/route.h>
60 #include <net/ip_fib.h>
61 #include <net/rtnetlink.h>
62 #include <net/net_namespace.h>
63 #include <net/addrconf.h>
64
65 #define IPV6ONLY_FLAGS \
66 (IFA_F_NODAD | IFA_F_OPTIMISTIC | IFA_F_DADFAILED | \
67 IFA_F_HOMEADDRESS | IFA_F_TENTATIVE | \
68 IFA_F_MANAGETEMPADDR | IFA_F_STABLE_PRIVACY)
69
70 static struct ipv4_devconf ipv4_devconf = {
71 .data = {
72 [IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1,
73 [IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1,
74 [IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1,
75 [IPV4_DEVCONF_SHARED_MEDIA - 1] = 1,
76 [IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL - 1] = 10000 /*ms*/,
77 [IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL - 1] = 1000 /*ms*/,
78 },
79 };
80
81 static struct ipv4_devconf ipv4_devconf_dflt = {
82 .data = {
83 [IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1,
84 [IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1,
85 [IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1,
86 [IPV4_DEVCONF_SHARED_MEDIA - 1] = 1,
87 [IPV4_DEVCONF_ACCEPT_SOURCE_ROUTE - 1] = 1,
88 [IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL - 1] = 10000 /*ms*/,
89 [IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL - 1] = 1000 /*ms*/,
90 },
91 };
92
93 #define IPV4_DEVCONF_DFLT(net, attr) \
94 IPV4_DEVCONF((*net->ipv4.devconf_dflt), attr)
95
96 static const struct nla_policy ifa_ipv4_policy[IFA_MAX+1] = {
97 [IFA_LOCAL] = { .type = NLA_U32 },
98 [IFA_ADDRESS] = { .type = NLA_U32 },
99 [IFA_BROADCAST] = { .type = NLA_U32 },
100 [IFA_LABEL] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
101 [IFA_CACHEINFO] = { .len = sizeof(struct ifa_cacheinfo) },
102 [IFA_FLAGS] = { .type = NLA_U32 },
103 [IFA_RT_PRIORITY] = { .type = NLA_U32 },
104 [IFA_TARGET_NETNSID] = { .type = NLA_S32 },
105 };
106
107 struct inet_fill_args {
108 u32 portid;
109 u32 seq;
110 int event;
111 unsigned int flags;
112 int netnsid;
113 int ifindex;
114 };
115
116 #define IN4_ADDR_HSIZE_SHIFT 8
117 #define IN4_ADDR_HSIZE (1U << IN4_ADDR_HSIZE_SHIFT)
118
119 static struct hlist_head inet_addr_lst[IN4_ADDR_HSIZE];
120
inet_addr_hash(const struct net * net,__be32 addr)121 static u32 inet_addr_hash(const struct net *net, __be32 addr)
122 {
123 u32 val = (__force u32) addr ^ net_hash_mix(net);
124
125 return hash_32(val, IN4_ADDR_HSIZE_SHIFT);
126 }
127
inet_hash_insert(struct net * net,struct in_ifaddr * ifa)128 static void inet_hash_insert(struct net *net, struct in_ifaddr *ifa)
129 {
130 u32 hash = inet_addr_hash(net, ifa->ifa_local);
131
132 ASSERT_RTNL();
133 hlist_add_head_rcu(&ifa->hash, &inet_addr_lst[hash]);
134 }
135
inet_hash_remove(struct in_ifaddr * ifa)136 static void inet_hash_remove(struct in_ifaddr *ifa)
137 {
138 ASSERT_RTNL();
139 hlist_del_init_rcu(&ifa->hash);
140 }
141
142 /**
143 * __ip_dev_find - find the first device with a given source address.
144 * @net: the net namespace
145 * @addr: the source address
146 * @devref: if true, take a reference on the found device
147 *
148 * If a caller uses devref=false, it should be protected by RCU, or RTNL
149 */
__ip_dev_find(struct net * net,__be32 addr,bool devref)150 struct net_device *__ip_dev_find(struct net *net, __be32 addr, bool devref)
151 {
152 struct net_device *result = NULL;
153 struct in_ifaddr *ifa;
154
155 rcu_read_lock();
156 ifa = inet_lookup_ifaddr_rcu(net, addr);
157 if (!ifa) {
158 struct flowi4 fl4 = { .daddr = addr };
159 struct fib_result res = { 0 };
160 struct fib_table *local;
161
162 /* Fallback to FIB local table so that communication
163 * over loopback subnets work.
164 */
165 local = fib_get_table(net, RT_TABLE_LOCAL);
166 if (local &&
167 !fib_table_lookup(local, &fl4, &res, FIB_LOOKUP_NOREF) &&
168 res.type == RTN_LOCAL)
169 result = FIB_RES_DEV(res);
170 } else {
171 result = ifa->ifa_dev->dev;
172 }
173 if (result && devref)
174 dev_hold(result);
175 rcu_read_unlock();
176 return result;
177 }
178 EXPORT_SYMBOL(__ip_dev_find);
179
180 /* called under RCU lock */
inet_lookup_ifaddr_rcu(struct net * net,__be32 addr)181 struct in_ifaddr *inet_lookup_ifaddr_rcu(struct net *net, __be32 addr)
182 {
183 u32 hash = inet_addr_hash(net, addr);
184 struct in_ifaddr *ifa;
185
186 hlist_for_each_entry_rcu(ifa, &inet_addr_lst[hash], hash)
187 if (ifa->ifa_local == addr &&
188 net_eq(dev_net(ifa->ifa_dev->dev), net))
189 return ifa;
190
191 return NULL;
192 }
193
194 static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32);
195
196 static BLOCKING_NOTIFIER_HEAD(inetaddr_chain);
197 static BLOCKING_NOTIFIER_HEAD(inetaddr_validator_chain);
198 static void inet_del_ifa(struct in_device *in_dev,
199 struct in_ifaddr __rcu **ifap,
200 int destroy);
201 #ifdef CONFIG_SYSCTL
202 static int devinet_sysctl_register(struct in_device *idev);
203 static void devinet_sysctl_unregister(struct in_device *idev);
204 #else
devinet_sysctl_register(struct in_device * idev)205 static int devinet_sysctl_register(struct in_device *idev)
206 {
207 return 0;
208 }
devinet_sysctl_unregister(struct in_device * idev)209 static void devinet_sysctl_unregister(struct in_device *idev)
210 {
211 }
212 #endif
213
214 /* Locks all the inet devices. */
215
inet_alloc_ifa(void)216 static struct in_ifaddr *inet_alloc_ifa(void)
217 {
218 return kzalloc(sizeof(struct in_ifaddr), GFP_KERNEL);
219 }
220
inet_rcu_free_ifa(struct rcu_head * head)221 static void inet_rcu_free_ifa(struct rcu_head *head)
222 {
223 struct in_ifaddr *ifa = container_of(head, struct in_ifaddr, rcu_head);
224 if (ifa->ifa_dev)
225 in_dev_put(ifa->ifa_dev);
226 kfree(ifa);
227 }
228
inet_free_ifa(struct in_ifaddr * ifa)229 static void inet_free_ifa(struct in_ifaddr *ifa)
230 {
231 call_rcu(&ifa->rcu_head, inet_rcu_free_ifa);
232 }
233
in_dev_finish_destroy(struct in_device * idev)234 void in_dev_finish_destroy(struct in_device *idev)
235 {
236 struct net_device *dev = idev->dev;
237
238 WARN_ON(idev->ifa_list);
239 WARN_ON(idev->mc_list);
240 kfree(rcu_dereference_protected(idev->mc_hash, 1));
241 #ifdef NET_REFCNT_DEBUG
242 pr_debug("%s: %p=%s\n", __func__, idev, dev ? dev->name : "NIL");
243 #endif
244 dev_put(dev);
245 if (!idev->dead)
246 pr_err("Freeing alive in_device %p\n", idev);
247 else
248 kfree(idev);
249 }
250 EXPORT_SYMBOL(in_dev_finish_destroy);
251
inetdev_init(struct net_device * dev)252 static struct in_device *inetdev_init(struct net_device *dev)
253 {
254 struct in_device *in_dev;
255 int err = -ENOMEM;
256
257 ASSERT_RTNL();
258
259 in_dev = kzalloc(sizeof(*in_dev), GFP_KERNEL);
260 if (!in_dev)
261 goto out;
262 memcpy(&in_dev->cnf, dev_net(dev)->ipv4.devconf_dflt,
263 sizeof(in_dev->cnf));
264 in_dev->cnf.sysctl = NULL;
265 in_dev->dev = dev;
266 in_dev->arp_parms = neigh_parms_alloc(dev, &arp_tbl);
267 if (!in_dev->arp_parms)
268 goto out_kfree;
269 if (IPV4_DEVCONF(in_dev->cnf, FORWARDING))
270 dev_disable_lro(dev);
271 /* Reference in_dev->dev */
272 dev_hold(dev);
273 /* Account for reference dev->ip_ptr (below) */
274 refcount_set(&in_dev->refcnt, 1);
275
276 err = devinet_sysctl_register(in_dev);
277 if (err) {
278 in_dev->dead = 1;
279 in_dev_put(in_dev);
280 in_dev = NULL;
281 goto out;
282 }
283 ip_mc_init_dev(in_dev);
284 if (dev->flags & IFF_UP)
285 ip_mc_up(in_dev);
286
287 /* we can receive as soon as ip_ptr is set -- do this last */
288 rcu_assign_pointer(dev->ip_ptr, in_dev);
289 out:
290 return in_dev ?: ERR_PTR(err);
291 out_kfree:
292 kfree(in_dev);
293 in_dev = NULL;
294 goto out;
295 }
296
in_dev_rcu_put(struct rcu_head * head)297 static void in_dev_rcu_put(struct rcu_head *head)
298 {
299 struct in_device *idev = container_of(head, struct in_device, rcu_head);
300 in_dev_put(idev);
301 }
302
inetdev_destroy(struct in_device * in_dev)303 static void inetdev_destroy(struct in_device *in_dev)
304 {
305 struct net_device *dev;
306 struct in_ifaddr *ifa;
307
308 ASSERT_RTNL();
309
310 dev = in_dev->dev;
311
312 in_dev->dead = 1;
313
314 ip_mc_destroy_dev(in_dev);
315
316 while ((ifa = rtnl_dereference(in_dev->ifa_list)) != NULL) {
317 inet_del_ifa(in_dev, &in_dev->ifa_list, 0);
318 inet_free_ifa(ifa);
319 }
320
321 RCU_INIT_POINTER(dev->ip_ptr, NULL);
322
323 devinet_sysctl_unregister(in_dev);
324 neigh_parms_release(&arp_tbl, in_dev->arp_parms);
325 arp_ifdown(dev);
326
327 call_rcu(&in_dev->rcu_head, in_dev_rcu_put);
328 }
329
inet_addr_onlink(struct in_device * in_dev,__be32 a,__be32 b)330 int inet_addr_onlink(struct in_device *in_dev, __be32 a, __be32 b)
331 {
332 const struct in_ifaddr *ifa;
333
334 rcu_read_lock();
335 in_dev_for_each_ifa_rcu(ifa, in_dev) {
336 if (inet_ifa_match(a, ifa)) {
337 if (!b || inet_ifa_match(b, ifa)) {
338 rcu_read_unlock();
339 return 1;
340 }
341 }
342 }
343 rcu_read_unlock();
344 return 0;
345 }
346
__inet_del_ifa(struct in_device * in_dev,struct in_ifaddr __rcu ** ifap,int destroy,struct nlmsghdr * nlh,u32 portid)347 static void __inet_del_ifa(struct in_device *in_dev,
348 struct in_ifaddr __rcu **ifap,
349 int destroy, struct nlmsghdr *nlh, u32 portid)
350 {
351 struct in_ifaddr *promote = NULL;
352 struct in_ifaddr *ifa, *ifa1;
353 struct in_ifaddr *last_prim;
354 struct in_ifaddr *prev_prom = NULL;
355 int do_promote = IN_DEV_PROMOTE_SECONDARIES(in_dev);
356
357 ASSERT_RTNL();
358
359 ifa1 = rtnl_dereference(*ifap);
360 last_prim = rtnl_dereference(in_dev->ifa_list);
361 if (in_dev->dead)
362 goto no_promotions;
363
364 /* 1. Deleting primary ifaddr forces deletion all secondaries
365 * unless alias promotion is set
366 **/
367
368 if (!(ifa1->ifa_flags & IFA_F_SECONDARY)) {
369 struct in_ifaddr __rcu **ifap1 = &ifa1->ifa_next;
370
371 while ((ifa = rtnl_dereference(*ifap1)) != NULL) {
372 if (!(ifa->ifa_flags & IFA_F_SECONDARY) &&
373 ifa1->ifa_scope <= ifa->ifa_scope)
374 last_prim = ifa;
375
376 if (!(ifa->ifa_flags & IFA_F_SECONDARY) ||
377 ifa1->ifa_mask != ifa->ifa_mask ||
378 !inet_ifa_match(ifa1->ifa_address, ifa)) {
379 ifap1 = &ifa->ifa_next;
380 prev_prom = ifa;
381 continue;
382 }
383
384 if (!do_promote) {
385 inet_hash_remove(ifa);
386 *ifap1 = ifa->ifa_next;
387
388 rtmsg_ifa(RTM_DELADDR, ifa, nlh, portid);
389 blocking_notifier_call_chain(&inetaddr_chain,
390 NETDEV_DOWN, ifa);
391 inet_free_ifa(ifa);
392 } else {
393 promote = ifa;
394 break;
395 }
396 }
397 }
398
399 /* On promotion all secondaries from subnet are changing
400 * the primary IP, we must remove all their routes silently
401 * and later to add them back with new prefsrc. Do this
402 * while all addresses are on the device list.
403 */
404 for (ifa = promote; ifa; ifa = rtnl_dereference(ifa->ifa_next)) {
405 if (ifa1->ifa_mask == ifa->ifa_mask &&
406 inet_ifa_match(ifa1->ifa_address, ifa))
407 fib_del_ifaddr(ifa, ifa1);
408 }
409
410 no_promotions:
411 /* 2. Unlink it */
412
413 *ifap = ifa1->ifa_next;
414 inet_hash_remove(ifa1);
415
416 /* 3. Announce address deletion */
417
418 /* Send message first, then call notifier.
419 At first sight, FIB update triggered by notifier
420 will refer to already deleted ifaddr, that could confuse
421 netlink listeners. It is not true: look, gated sees
422 that route deleted and if it still thinks that ifaddr
423 is valid, it will try to restore deleted routes... Grr.
424 So that, this order is correct.
425 */
426 rtmsg_ifa(RTM_DELADDR, ifa1, nlh, portid);
427 blocking_notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa1);
428
429 if (promote) {
430 struct in_ifaddr *next_sec;
431
432 next_sec = rtnl_dereference(promote->ifa_next);
433 if (prev_prom) {
434 struct in_ifaddr *last_sec;
435
436 rcu_assign_pointer(prev_prom->ifa_next, next_sec);
437
438 last_sec = rtnl_dereference(last_prim->ifa_next);
439 rcu_assign_pointer(promote->ifa_next, last_sec);
440 rcu_assign_pointer(last_prim->ifa_next, promote);
441 }
442
443 promote->ifa_flags &= ~IFA_F_SECONDARY;
444 rtmsg_ifa(RTM_NEWADDR, promote, nlh, portid);
445 blocking_notifier_call_chain(&inetaddr_chain,
446 NETDEV_UP, promote);
447 for (ifa = next_sec; ifa;
448 ifa = rtnl_dereference(ifa->ifa_next)) {
449 if (ifa1->ifa_mask != ifa->ifa_mask ||
450 !inet_ifa_match(ifa1->ifa_address, ifa))
451 continue;
452 fib_add_ifaddr(ifa);
453 }
454
455 }
456 if (destroy)
457 inet_free_ifa(ifa1);
458 }
459
inet_del_ifa(struct in_device * in_dev,struct in_ifaddr __rcu ** ifap,int destroy)460 static void inet_del_ifa(struct in_device *in_dev,
461 struct in_ifaddr __rcu **ifap,
462 int destroy)
463 {
464 __inet_del_ifa(in_dev, ifap, destroy, NULL, 0);
465 }
466
467 static void check_lifetime(struct work_struct *work);
468
469 static DECLARE_DELAYED_WORK(check_lifetime_work, check_lifetime);
470
__inet_insert_ifa(struct in_ifaddr * ifa,struct nlmsghdr * nlh,u32 portid,struct netlink_ext_ack * extack)471 static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh,
472 u32 portid, struct netlink_ext_ack *extack)
473 {
474 struct in_ifaddr __rcu **last_primary, **ifap;
475 struct in_device *in_dev = ifa->ifa_dev;
476 struct in_validator_info ivi;
477 struct in_ifaddr *ifa1;
478 int ret;
479
480 ASSERT_RTNL();
481
482 if (!ifa->ifa_local) {
483 inet_free_ifa(ifa);
484 return 0;
485 }
486
487 ifa->ifa_flags &= ~IFA_F_SECONDARY;
488 last_primary = &in_dev->ifa_list;
489
490 /* Don't set IPv6 only flags to IPv4 addresses */
491 ifa->ifa_flags &= ~IPV6ONLY_FLAGS;
492
493 ifap = &in_dev->ifa_list;
494 ifa1 = rtnl_dereference(*ifap);
495
496 while (ifa1) {
497 if (!(ifa1->ifa_flags & IFA_F_SECONDARY) &&
498 ifa->ifa_scope <= ifa1->ifa_scope)
499 last_primary = &ifa1->ifa_next;
500 if (ifa1->ifa_mask == ifa->ifa_mask &&
501 inet_ifa_match(ifa1->ifa_address, ifa)) {
502 if (ifa1->ifa_local == ifa->ifa_local) {
503 inet_free_ifa(ifa);
504 return -EEXIST;
505 }
506 if (ifa1->ifa_scope != ifa->ifa_scope) {
507 inet_free_ifa(ifa);
508 return -EINVAL;
509 }
510 ifa->ifa_flags |= IFA_F_SECONDARY;
511 }
512
513 ifap = &ifa1->ifa_next;
514 ifa1 = rtnl_dereference(*ifap);
515 }
516
517 /* Allow any devices that wish to register ifaddr validtors to weigh
518 * in now, before changes are committed. The rntl lock is serializing
519 * access here, so the state should not change between a validator call
520 * and a final notify on commit. This isn't invoked on promotion under
521 * the assumption that validators are checking the address itself, and
522 * not the flags.
523 */
524 ivi.ivi_addr = ifa->ifa_address;
525 ivi.ivi_dev = ifa->ifa_dev;
526 ivi.extack = extack;
527 ret = blocking_notifier_call_chain(&inetaddr_validator_chain,
528 NETDEV_UP, &ivi);
529 ret = notifier_to_errno(ret);
530 if (ret) {
531 inet_free_ifa(ifa);
532 return ret;
533 }
534
535 if (!(ifa->ifa_flags & IFA_F_SECONDARY)) {
536 prandom_seed((__force u32) ifa->ifa_local);
537 ifap = last_primary;
538 }
539
540 rcu_assign_pointer(ifa->ifa_next, *ifap);
541 rcu_assign_pointer(*ifap, ifa);
542
543 inet_hash_insert(dev_net(in_dev->dev), ifa);
544
545 cancel_delayed_work(&check_lifetime_work);
546 queue_delayed_work(system_power_efficient_wq, &check_lifetime_work, 0);
547
548 /* Send message first, then call notifier.
549 Notifier will trigger FIB update, so that
550 listeners of netlink will know about new ifaddr */
551 rtmsg_ifa(RTM_NEWADDR, ifa, nlh, portid);
552 blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa);
553
554 return 0;
555 }
556
inet_insert_ifa(struct in_ifaddr * ifa)557 static int inet_insert_ifa(struct in_ifaddr *ifa)
558 {
559 return __inet_insert_ifa(ifa, NULL, 0, NULL);
560 }
561
inet_set_ifa(struct net_device * dev,struct in_ifaddr * ifa)562 static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa)
563 {
564 struct in_device *in_dev = __in_dev_get_rtnl(dev);
565
566 ASSERT_RTNL();
567
568 if (!in_dev) {
569 inet_free_ifa(ifa);
570 return -ENOBUFS;
571 }
572 ipv4_devconf_setall(in_dev);
573 neigh_parms_data_state_setall(in_dev->arp_parms);
574 if (ifa->ifa_dev != in_dev) {
575 WARN_ON(ifa->ifa_dev);
576 in_dev_hold(in_dev);
577 ifa->ifa_dev = in_dev;
578 }
579 if (ipv4_is_loopback(ifa->ifa_local))
580 ifa->ifa_scope = RT_SCOPE_HOST;
581 return inet_insert_ifa(ifa);
582 }
583
584 /* Caller must hold RCU or RTNL :
585 * We dont take a reference on found in_device
586 */
inetdev_by_index(struct net * net,int ifindex)587 struct in_device *inetdev_by_index(struct net *net, int ifindex)
588 {
589 struct net_device *dev;
590 struct in_device *in_dev = NULL;
591
592 rcu_read_lock();
593 dev = dev_get_by_index_rcu(net, ifindex);
594 if (dev)
595 in_dev = rcu_dereference_rtnl(dev->ip_ptr);
596 rcu_read_unlock();
597 return in_dev;
598 }
599 EXPORT_SYMBOL(inetdev_by_index);
600
601 /* Called only from RTNL semaphored context. No locks. */
602
inet_ifa_byprefix(struct in_device * in_dev,__be32 prefix,__be32 mask)603 struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix,
604 __be32 mask)
605 {
606 struct in_ifaddr *ifa;
607
608 ASSERT_RTNL();
609
610 in_dev_for_each_ifa_rtnl(ifa, in_dev) {
611 if (ifa->ifa_mask == mask && inet_ifa_match(prefix, ifa))
612 return ifa;
613 }
614 return NULL;
615 }
616
ip_mc_config(struct sock * sk,bool join,const struct in_ifaddr * ifa)617 static int ip_mc_config(struct sock *sk, bool join, const struct in_ifaddr *ifa)
618 {
619 struct ip_mreqn mreq = {
620 .imr_multiaddr.s_addr = ifa->ifa_address,
621 .imr_ifindex = ifa->ifa_dev->dev->ifindex,
622 };
623 int ret;
624
625 ASSERT_RTNL();
626
627 lock_sock(sk);
628 if (join)
629 ret = ip_mc_join_group(sk, &mreq);
630 else
631 ret = ip_mc_leave_group(sk, &mreq);
632 release_sock(sk);
633
634 return ret;
635 }
636
inet_rtm_deladdr(struct sk_buff * skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)637 static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
638 struct netlink_ext_ack *extack)
639 {
640 struct net *net = sock_net(skb->sk);
641 struct in_ifaddr __rcu **ifap;
642 struct nlattr *tb[IFA_MAX+1];
643 struct in_device *in_dev;
644 struct ifaddrmsg *ifm;
645 struct in_ifaddr *ifa;
646
647 int err = -EINVAL;
648
649 ASSERT_RTNL();
650
651 err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
652 ifa_ipv4_policy, extack);
653 if (err < 0)
654 goto errout;
655
656 ifm = nlmsg_data(nlh);
657 in_dev = inetdev_by_index(net, ifm->ifa_index);
658 if (!in_dev) {
659 err = -ENODEV;
660 goto errout;
661 }
662
663 for (ifap = &in_dev->ifa_list; (ifa = rtnl_dereference(*ifap)) != NULL;
664 ifap = &ifa->ifa_next) {
665 if (tb[IFA_LOCAL] &&
666 ifa->ifa_local != nla_get_in_addr(tb[IFA_LOCAL]))
667 continue;
668
669 if (tb[IFA_LABEL] && nla_strcmp(tb[IFA_LABEL], ifa->ifa_label))
670 continue;
671
672 if (tb[IFA_ADDRESS] &&
673 (ifm->ifa_prefixlen != ifa->ifa_prefixlen ||
674 !inet_ifa_match(nla_get_in_addr(tb[IFA_ADDRESS]), ifa)))
675 continue;
676
677 if (ipv4_is_multicast(ifa->ifa_address))
678 ip_mc_config(net->ipv4.mc_autojoin_sk, false, ifa);
679 __inet_del_ifa(in_dev, ifap, 1, nlh, NETLINK_CB(skb).portid);
680 return 0;
681 }
682
683 err = -EADDRNOTAVAIL;
684 errout:
685 return err;
686 }
687
688 #define INFINITY_LIFE_TIME 0xFFFFFFFF
689
check_lifetime(struct work_struct * work)690 static void check_lifetime(struct work_struct *work)
691 {
692 unsigned long now, next, next_sec, next_sched;
693 struct in_ifaddr *ifa;
694 struct hlist_node *n;
695 int i;
696
697 now = jiffies;
698 next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
699
700 for (i = 0; i < IN4_ADDR_HSIZE; i++) {
701 bool change_needed = false;
702
703 rcu_read_lock();
704 hlist_for_each_entry_rcu(ifa, &inet_addr_lst[i], hash) {
705 unsigned long age;
706
707 if (ifa->ifa_flags & IFA_F_PERMANENT)
708 continue;
709
710 /* We try to batch several events at once. */
711 age = (now - ifa->ifa_tstamp +
712 ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
713
714 if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME &&
715 age >= ifa->ifa_valid_lft) {
716 change_needed = true;
717 } else if (ifa->ifa_preferred_lft ==
718 INFINITY_LIFE_TIME) {
719 continue;
720 } else if (age >= ifa->ifa_preferred_lft) {
721 if (time_before(ifa->ifa_tstamp +
722 ifa->ifa_valid_lft * HZ, next))
723 next = ifa->ifa_tstamp +
724 ifa->ifa_valid_lft * HZ;
725
726 if (!(ifa->ifa_flags & IFA_F_DEPRECATED))
727 change_needed = true;
728 } else if (time_before(ifa->ifa_tstamp +
729 ifa->ifa_preferred_lft * HZ,
730 next)) {
731 next = ifa->ifa_tstamp +
732 ifa->ifa_preferred_lft * HZ;
733 }
734 }
735 rcu_read_unlock();
736 if (!change_needed)
737 continue;
738 rtnl_lock();
739 hlist_for_each_entry_safe(ifa, n, &inet_addr_lst[i], hash) {
740 unsigned long age;
741
742 if (ifa->ifa_flags & IFA_F_PERMANENT)
743 continue;
744
745 /* We try to batch several events at once. */
746 age = (now - ifa->ifa_tstamp +
747 ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
748
749 if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME &&
750 age >= ifa->ifa_valid_lft) {
751 struct in_ifaddr __rcu **ifap;
752 struct in_ifaddr *tmp;
753
754 ifap = &ifa->ifa_dev->ifa_list;
755 tmp = rtnl_dereference(*ifap);
756 while (tmp) {
757 if (tmp == ifa) {
758 inet_del_ifa(ifa->ifa_dev,
759 ifap, 1);
760 break;
761 }
762 ifap = &tmp->ifa_next;
763 tmp = rtnl_dereference(*ifap);
764 }
765 } else if (ifa->ifa_preferred_lft !=
766 INFINITY_LIFE_TIME &&
767 age >= ifa->ifa_preferred_lft &&
768 !(ifa->ifa_flags & IFA_F_DEPRECATED)) {
769 ifa->ifa_flags |= IFA_F_DEPRECATED;
770 rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0);
771 }
772 }
773 rtnl_unlock();
774 }
775
776 next_sec = round_jiffies_up(next);
777 next_sched = next;
778
779 /* If rounded timeout is accurate enough, accept it. */
780 if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
781 next_sched = next_sec;
782
783 now = jiffies;
784 /* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
785 if (time_before(next_sched, now + ADDRCONF_TIMER_FUZZ_MAX))
786 next_sched = now + ADDRCONF_TIMER_FUZZ_MAX;
787
788 queue_delayed_work(system_power_efficient_wq, &check_lifetime_work,
789 next_sched - now);
790 }
791
set_ifa_lifetime(struct in_ifaddr * ifa,__u32 valid_lft,__u32 prefered_lft)792 static void set_ifa_lifetime(struct in_ifaddr *ifa, __u32 valid_lft,
793 __u32 prefered_lft)
794 {
795 unsigned long timeout;
796
797 ifa->ifa_flags &= ~(IFA_F_PERMANENT | IFA_F_DEPRECATED);
798
799 timeout = addrconf_timeout_fixup(valid_lft, HZ);
800 if (addrconf_finite_timeout(timeout))
801 ifa->ifa_valid_lft = timeout;
802 else
803 ifa->ifa_flags |= IFA_F_PERMANENT;
804
805 timeout = addrconf_timeout_fixup(prefered_lft, HZ);
806 if (addrconf_finite_timeout(timeout)) {
807 if (timeout == 0)
808 ifa->ifa_flags |= IFA_F_DEPRECATED;
809 ifa->ifa_preferred_lft = timeout;
810 }
811 ifa->ifa_tstamp = jiffies;
812 if (!ifa->ifa_cstamp)
813 ifa->ifa_cstamp = ifa->ifa_tstamp;
814 }
815
rtm_to_ifaddr(struct net * net,struct nlmsghdr * nlh,__u32 * pvalid_lft,__u32 * pprefered_lft,struct netlink_ext_ack * extack)816 static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh,
817 __u32 *pvalid_lft, __u32 *pprefered_lft,
818 struct netlink_ext_ack *extack)
819 {
820 struct nlattr *tb[IFA_MAX+1];
821 struct in_ifaddr *ifa;
822 struct ifaddrmsg *ifm;
823 struct net_device *dev;
824 struct in_device *in_dev;
825 int err;
826
827 err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
828 ifa_ipv4_policy, extack);
829 if (err < 0)
830 goto errout;
831
832 ifm = nlmsg_data(nlh);
833 err = -EINVAL;
834 if (ifm->ifa_prefixlen > 32 || !tb[IFA_LOCAL])
835 goto errout;
836
837 dev = __dev_get_by_index(net, ifm->ifa_index);
838 err = -ENODEV;
839 if (!dev)
840 goto errout;
841
842 in_dev = __in_dev_get_rtnl(dev);
843 err = -ENOBUFS;
844 if (!in_dev)
845 goto errout;
846
847 ifa = inet_alloc_ifa();
848 if (!ifa)
849 /*
850 * A potential indev allocation can be left alive, it stays
851 * assigned to its device and is destroy with it.
852 */
853 goto errout;
854
855 ipv4_devconf_setall(in_dev);
856 neigh_parms_data_state_setall(in_dev->arp_parms);
857 in_dev_hold(in_dev);
858
859 if (!tb[IFA_ADDRESS])
860 tb[IFA_ADDRESS] = tb[IFA_LOCAL];
861
862 INIT_HLIST_NODE(&ifa->hash);
863 ifa->ifa_prefixlen = ifm->ifa_prefixlen;
864 ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen);
865 ifa->ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) :
866 ifm->ifa_flags;
867 ifa->ifa_scope = ifm->ifa_scope;
868 ifa->ifa_dev = in_dev;
869
870 ifa->ifa_local = nla_get_in_addr(tb[IFA_LOCAL]);
871 ifa->ifa_address = nla_get_in_addr(tb[IFA_ADDRESS]);
872
873 if (tb[IFA_BROADCAST])
874 ifa->ifa_broadcast = nla_get_in_addr(tb[IFA_BROADCAST]);
875
876 if (tb[IFA_LABEL])
877 nla_strlcpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ);
878 else
879 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
880
881 if (tb[IFA_RT_PRIORITY])
882 ifa->ifa_rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
883
884 if (tb[IFA_CACHEINFO]) {
885 struct ifa_cacheinfo *ci;
886
887 ci = nla_data(tb[IFA_CACHEINFO]);
888 if (!ci->ifa_valid || ci->ifa_prefered > ci->ifa_valid) {
889 err = -EINVAL;
890 goto errout_free;
891 }
892 *pvalid_lft = ci->ifa_valid;
893 *pprefered_lft = ci->ifa_prefered;
894 }
895
896 return ifa;
897
898 errout_free:
899 inet_free_ifa(ifa);
900 errout:
901 return ERR_PTR(err);
902 }
903
find_matching_ifa(struct in_ifaddr * ifa)904 static struct in_ifaddr *find_matching_ifa(struct in_ifaddr *ifa)
905 {
906 struct in_device *in_dev = ifa->ifa_dev;
907 struct in_ifaddr *ifa1;
908
909 if (!ifa->ifa_local)
910 return NULL;
911
912 in_dev_for_each_ifa_rtnl(ifa1, in_dev) {
913 if (ifa1->ifa_mask == ifa->ifa_mask &&
914 inet_ifa_match(ifa1->ifa_address, ifa) &&
915 ifa1->ifa_local == ifa->ifa_local)
916 return ifa1;
917 }
918 return NULL;
919 }
920
inet_rtm_newaddr(struct sk_buff * skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)921 static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
922 struct netlink_ext_ack *extack)
923 {
924 struct net *net = sock_net(skb->sk);
925 struct in_ifaddr *ifa;
926 struct in_ifaddr *ifa_existing;
927 __u32 valid_lft = INFINITY_LIFE_TIME;
928 __u32 prefered_lft = INFINITY_LIFE_TIME;
929
930 ASSERT_RTNL();
931
932 ifa = rtm_to_ifaddr(net, nlh, &valid_lft, &prefered_lft, extack);
933 if (IS_ERR(ifa))
934 return PTR_ERR(ifa);
935
936 ifa_existing = find_matching_ifa(ifa);
937 if (!ifa_existing) {
938 /* It would be best to check for !NLM_F_CREATE here but
939 * userspace already relies on not having to provide this.
940 */
941 set_ifa_lifetime(ifa, valid_lft, prefered_lft);
942 if (ifa->ifa_flags & IFA_F_MCAUTOJOIN) {
943 int ret = ip_mc_config(net->ipv4.mc_autojoin_sk,
944 true, ifa);
945
946 if (ret < 0) {
947 inet_free_ifa(ifa);
948 return ret;
949 }
950 }
951 return __inet_insert_ifa(ifa, nlh, NETLINK_CB(skb).portid,
952 extack);
953 } else {
954 u32 new_metric = ifa->ifa_rt_priority;
955
956 inet_free_ifa(ifa);
957
958 if (nlh->nlmsg_flags & NLM_F_EXCL ||
959 !(nlh->nlmsg_flags & NLM_F_REPLACE))
960 return -EEXIST;
961 ifa = ifa_existing;
962
963 if (ifa->ifa_rt_priority != new_metric) {
964 fib_modify_prefix_metric(ifa, new_metric);
965 ifa->ifa_rt_priority = new_metric;
966 }
967
968 set_ifa_lifetime(ifa, valid_lft, prefered_lft);
969 cancel_delayed_work(&check_lifetime_work);
970 queue_delayed_work(system_power_efficient_wq,
971 &check_lifetime_work, 0);
972 rtmsg_ifa(RTM_NEWADDR, ifa, nlh, NETLINK_CB(skb).portid);
973 }
974 return 0;
975 }
976
977 /*
978 * Determine a default network mask, based on the IP address.
979 */
980
inet_abc_len(__be32 addr)981 static int inet_abc_len(__be32 addr)
982 {
983 int rc = -1; /* Something else, probably a multicast. */
984
985 if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr))
986 rc = 0;
987 else {
988 __u32 haddr = ntohl(addr);
989 if (IN_CLASSA(haddr))
990 rc = 8;
991 else if (IN_CLASSB(haddr))
992 rc = 16;
993 else if (IN_CLASSC(haddr))
994 rc = 24;
995 else if (IN_CLASSE(haddr))
996 rc = 32;
997 }
998
999 return rc;
1000 }
1001
1002
devinet_ioctl(struct net * net,unsigned int cmd,struct ifreq * ifr)1003 int devinet_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr)
1004 {
1005 struct sockaddr_in sin_orig;
1006 struct sockaddr_in *sin = (struct sockaddr_in *)&ifr->ifr_addr;
1007 struct in_ifaddr __rcu **ifap = NULL;
1008 struct in_device *in_dev;
1009 struct in_ifaddr *ifa = NULL;
1010 struct net_device *dev;
1011 char *colon;
1012 int ret = -EFAULT;
1013 int tryaddrmatch = 0;
1014
1015 ifr->ifr_name[IFNAMSIZ - 1] = 0;
1016
1017 /* save original address for comparison */
1018 memcpy(&sin_orig, sin, sizeof(*sin));
1019
1020 colon = strchr(ifr->ifr_name, ':');
1021 if (colon)
1022 *colon = 0;
1023
1024 dev_load(net, ifr->ifr_name);
1025
1026 switch (cmd) {
1027 case SIOCGIFADDR: /* Get interface address */
1028 case SIOCGIFBRDADDR: /* Get the broadcast address */
1029 case SIOCGIFDSTADDR: /* Get the destination address */
1030 case SIOCGIFNETMASK: /* Get the netmask for the interface */
1031 /* Note that these ioctls will not sleep,
1032 so that we do not impose a lock.
1033 One day we will be forced to put shlock here (I mean SMP)
1034 */
1035 tryaddrmatch = (sin_orig.sin_family == AF_INET);
1036 memset(sin, 0, sizeof(*sin));
1037 sin->sin_family = AF_INET;
1038 break;
1039
1040 case SIOCSIFFLAGS:
1041 ret = -EPERM;
1042 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1043 goto out;
1044 break;
1045 case SIOCSIFADDR: /* Set interface address (and family) */
1046 case SIOCSIFBRDADDR: /* Set the broadcast address */
1047 case SIOCSIFDSTADDR: /* Set the destination address */
1048 case SIOCSIFNETMASK: /* Set the netmask for the interface */
1049 ret = -EPERM;
1050 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1051 goto out;
1052 ret = -EINVAL;
1053 if (sin->sin_family != AF_INET)
1054 goto out;
1055 break;
1056 default:
1057 ret = -EINVAL;
1058 goto out;
1059 }
1060
1061 rtnl_lock();
1062
1063 ret = -ENODEV;
1064 dev = __dev_get_by_name(net, ifr->ifr_name);
1065 if (!dev)
1066 goto done;
1067
1068 if (colon)
1069 *colon = ':';
1070
1071 in_dev = __in_dev_get_rtnl(dev);
1072 if (in_dev) {
1073 if (tryaddrmatch) {
1074 /* Matthias Andree */
1075 /* compare label and address (4.4BSD style) */
1076 /* note: we only do this for a limited set of ioctls
1077 and only if the original address family was AF_INET.
1078 This is checked above. */
1079
1080 for (ifap = &in_dev->ifa_list;
1081 (ifa = rtnl_dereference(*ifap)) != NULL;
1082 ifap = &ifa->ifa_next) {
1083 if (!strcmp(ifr->ifr_name, ifa->ifa_label) &&
1084 sin_orig.sin_addr.s_addr ==
1085 ifa->ifa_local) {
1086 break; /* found */
1087 }
1088 }
1089 }
1090 /* we didn't get a match, maybe the application is
1091 4.3BSD-style and passed in junk so we fall back to
1092 comparing just the label */
1093 if (!ifa) {
1094 for (ifap = &in_dev->ifa_list;
1095 (ifa = rtnl_dereference(*ifap)) != NULL;
1096 ifap = &ifa->ifa_next)
1097 if (!strcmp(ifr->ifr_name, ifa->ifa_label))
1098 break;
1099 }
1100 }
1101
1102 ret = -EADDRNOTAVAIL;
1103 if (!ifa && cmd != SIOCSIFADDR && cmd != SIOCSIFFLAGS)
1104 goto done;
1105
1106 switch (cmd) {
1107 case SIOCGIFADDR: /* Get interface address */
1108 ret = 0;
1109 sin->sin_addr.s_addr = ifa->ifa_local;
1110 break;
1111
1112 case SIOCGIFBRDADDR: /* Get the broadcast address */
1113 ret = 0;
1114 sin->sin_addr.s_addr = ifa->ifa_broadcast;
1115 break;
1116
1117 case SIOCGIFDSTADDR: /* Get the destination address */
1118 ret = 0;
1119 sin->sin_addr.s_addr = ifa->ifa_address;
1120 break;
1121
1122 case SIOCGIFNETMASK: /* Get the netmask for the interface */
1123 ret = 0;
1124 sin->sin_addr.s_addr = ifa->ifa_mask;
1125 break;
1126
1127 case SIOCSIFFLAGS:
1128 if (colon) {
1129 ret = -EADDRNOTAVAIL;
1130 if (!ifa)
1131 break;
1132 ret = 0;
1133 if (!(ifr->ifr_flags & IFF_UP))
1134 inet_del_ifa(in_dev, ifap, 1);
1135 break;
1136 }
1137 ret = dev_change_flags(dev, ifr->ifr_flags, NULL);
1138 break;
1139
1140 case SIOCSIFADDR: /* Set interface address (and family) */
1141 ret = -EINVAL;
1142 if (inet_abc_len(sin->sin_addr.s_addr) < 0)
1143 break;
1144
1145 if (!ifa) {
1146 ret = -ENOBUFS;
1147 ifa = inet_alloc_ifa();
1148 if (!ifa)
1149 break;
1150 INIT_HLIST_NODE(&ifa->hash);
1151 if (colon)
1152 memcpy(ifa->ifa_label, ifr->ifr_name, IFNAMSIZ);
1153 else
1154 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1155 } else {
1156 ret = 0;
1157 if (ifa->ifa_local == sin->sin_addr.s_addr)
1158 break;
1159 inet_del_ifa(in_dev, ifap, 0);
1160 ifa->ifa_broadcast = 0;
1161 ifa->ifa_scope = 0;
1162 }
1163
1164 ifa->ifa_address = ifa->ifa_local = sin->sin_addr.s_addr;
1165
1166 if (!(dev->flags & IFF_POINTOPOINT)) {
1167 ifa->ifa_prefixlen = inet_abc_len(ifa->ifa_address);
1168 ifa->ifa_mask = inet_make_mask(ifa->ifa_prefixlen);
1169 if ((dev->flags & IFF_BROADCAST) &&
1170 ifa->ifa_prefixlen < 31)
1171 ifa->ifa_broadcast = ifa->ifa_address |
1172 ~ifa->ifa_mask;
1173 } else {
1174 ifa->ifa_prefixlen = 32;
1175 ifa->ifa_mask = inet_make_mask(32);
1176 }
1177 set_ifa_lifetime(ifa, INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
1178 ret = inet_set_ifa(dev, ifa);
1179 break;
1180
1181 case SIOCSIFBRDADDR: /* Set the broadcast address */
1182 ret = 0;
1183 if (ifa->ifa_broadcast != sin->sin_addr.s_addr) {
1184 inet_del_ifa(in_dev, ifap, 0);
1185 ifa->ifa_broadcast = sin->sin_addr.s_addr;
1186 inet_insert_ifa(ifa);
1187 }
1188 break;
1189
1190 case SIOCSIFDSTADDR: /* Set the destination address */
1191 ret = 0;
1192 if (ifa->ifa_address == sin->sin_addr.s_addr)
1193 break;
1194 ret = -EINVAL;
1195 if (inet_abc_len(sin->sin_addr.s_addr) < 0)
1196 break;
1197 ret = 0;
1198 inet_del_ifa(in_dev, ifap, 0);
1199 ifa->ifa_address = sin->sin_addr.s_addr;
1200 inet_insert_ifa(ifa);
1201 break;
1202
1203 case SIOCSIFNETMASK: /* Set the netmask for the interface */
1204
1205 /*
1206 * The mask we set must be legal.
1207 */
1208 ret = -EINVAL;
1209 if (bad_mask(sin->sin_addr.s_addr, 0))
1210 break;
1211 ret = 0;
1212 if (ifa->ifa_mask != sin->sin_addr.s_addr) {
1213 __be32 old_mask = ifa->ifa_mask;
1214 inet_del_ifa(in_dev, ifap, 0);
1215 ifa->ifa_mask = sin->sin_addr.s_addr;
1216 ifa->ifa_prefixlen = inet_mask_len(ifa->ifa_mask);
1217
1218 /* See if current broadcast address matches
1219 * with current netmask, then recalculate
1220 * the broadcast address. Otherwise it's a
1221 * funny address, so don't touch it since
1222 * the user seems to know what (s)he's doing...
1223 */
1224 if ((dev->flags & IFF_BROADCAST) &&
1225 (ifa->ifa_prefixlen < 31) &&
1226 (ifa->ifa_broadcast ==
1227 (ifa->ifa_local|~old_mask))) {
1228 ifa->ifa_broadcast = (ifa->ifa_local |
1229 ~sin->sin_addr.s_addr);
1230 }
1231 inet_insert_ifa(ifa);
1232 }
1233 break;
1234 }
1235 done:
1236 rtnl_unlock();
1237 out:
1238 return ret;
1239 }
1240
inet_gifconf(struct net_device * dev,char __user * buf,int len,int size)1241 static int inet_gifconf(struct net_device *dev, char __user *buf, int len, int size)
1242 {
1243 struct in_device *in_dev = __in_dev_get_rtnl(dev);
1244 const struct in_ifaddr *ifa;
1245 struct ifreq ifr;
1246 int done = 0;
1247
1248 if (WARN_ON(size > sizeof(struct ifreq)))
1249 goto out;
1250
1251 if (!in_dev)
1252 goto out;
1253
1254 in_dev_for_each_ifa_rtnl(ifa, in_dev) {
1255 if (!buf) {
1256 done += size;
1257 continue;
1258 }
1259 if (len < size)
1260 break;
1261 memset(&ifr, 0, sizeof(struct ifreq));
1262 strcpy(ifr.ifr_name, ifa->ifa_label);
1263
1264 (*(struct sockaddr_in *)&ifr.ifr_addr).sin_family = AF_INET;
1265 (*(struct sockaddr_in *)&ifr.ifr_addr).sin_addr.s_addr =
1266 ifa->ifa_local;
1267
1268 if (copy_to_user(buf + done, &ifr, size)) {
1269 done = -EFAULT;
1270 break;
1271 }
1272 len -= size;
1273 done += size;
1274 }
1275 out:
1276 return done;
1277 }
1278
in_dev_select_addr(const struct in_device * in_dev,int scope)1279 static __be32 in_dev_select_addr(const struct in_device *in_dev,
1280 int scope)
1281 {
1282 const struct in_ifaddr *ifa;
1283
1284 in_dev_for_each_ifa_rcu(ifa, in_dev) {
1285 if (ifa->ifa_flags & IFA_F_SECONDARY)
1286 continue;
1287 if (ifa->ifa_scope != RT_SCOPE_LINK &&
1288 ifa->ifa_scope <= scope)
1289 return ifa->ifa_local;
1290 }
1291
1292 return 0;
1293 }
1294
inet_select_addr(const struct net_device * dev,__be32 dst,int scope)1295 __be32 inet_select_addr(const struct net_device *dev, __be32 dst, int scope)
1296 {
1297 const struct in_ifaddr *ifa;
1298 __be32 addr = 0;
1299 unsigned char localnet_scope = RT_SCOPE_HOST;
1300 struct in_device *in_dev;
1301 struct net *net = dev_net(dev);
1302 int master_idx;
1303
1304 rcu_read_lock();
1305 in_dev = __in_dev_get_rcu(dev);
1306 if (!in_dev)
1307 goto no_in_dev;
1308
1309 if (unlikely(IN_DEV_ROUTE_LOCALNET(in_dev)))
1310 localnet_scope = RT_SCOPE_LINK;
1311
1312 in_dev_for_each_ifa_rcu(ifa, in_dev) {
1313 if (ifa->ifa_flags & IFA_F_SECONDARY)
1314 continue;
1315 if (min(ifa->ifa_scope, localnet_scope) > scope)
1316 continue;
1317 if (!dst || inet_ifa_match(dst, ifa)) {
1318 addr = ifa->ifa_local;
1319 break;
1320 }
1321 if (!addr)
1322 addr = ifa->ifa_local;
1323 }
1324
1325 if (addr)
1326 goto out_unlock;
1327 no_in_dev:
1328 master_idx = l3mdev_master_ifindex_rcu(dev);
1329
1330 /* For VRFs, the VRF device takes the place of the loopback device,
1331 * with addresses on it being preferred. Note in such cases the
1332 * loopback device will be among the devices that fail the master_idx
1333 * equality check in the loop below.
1334 */
1335 if (master_idx &&
1336 (dev = dev_get_by_index_rcu(net, master_idx)) &&
1337 (in_dev = __in_dev_get_rcu(dev))) {
1338 addr = in_dev_select_addr(in_dev, scope);
1339 if (addr)
1340 goto out_unlock;
1341 }
1342
1343 /* Not loopback addresses on loopback should be preferred
1344 in this case. It is important that lo is the first interface
1345 in dev_base list.
1346 */
1347 for_each_netdev_rcu(net, dev) {
1348 if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1349 continue;
1350
1351 in_dev = __in_dev_get_rcu(dev);
1352 if (!in_dev)
1353 continue;
1354
1355 addr = in_dev_select_addr(in_dev, scope);
1356 if (addr)
1357 goto out_unlock;
1358 }
1359 out_unlock:
1360 rcu_read_unlock();
1361 return addr;
1362 }
1363 EXPORT_SYMBOL(inet_select_addr);
1364
confirm_addr_indev(struct in_device * in_dev,__be32 dst,__be32 local,int scope)1365 static __be32 confirm_addr_indev(struct in_device *in_dev, __be32 dst,
1366 __be32 local, int scope)
1367 {
1368 unsigned char localnet_scope = RT_SCOPE_HOST;
1369 const struct in_ifaddr *ifa;
1370 __be32 addr = 0;
1371 int same = 0;
1372
1373 if (unlikely(IN_DEV_ROUTE_LOCALNET(in_dev)))
1374 localnet_scope = RT_SCOPE_LINK;
1375
1376 in_dev_for_each_ifa_rcu(ifa, in_dev) {
1377 unsigned char min_scope = min(ifa->ifa_scope, localnet_scope);
1378
1379 if (!addr &&
1380 (local == ifa->ifa_local || !local) &&
1381 min_scope <= scope) {
1382 addr = ifa->ifa_local;
1383 if (same)
1384 break;
1385 }
1386 if (!same) {
1387 same = (!local || inet_ifa_match(local, ifa)) &&
1388 (!dst || inet_ifa_match(dst, ifa));
1389 if (same && addr) {
1390 if (local || !dst)
1391 break;
1392 /* Is the selected addr into dst subnet? */
1393 if (inet_ifa_match(addr, ifa))
1394 break;
1395 /* No, then can we use new local src? */
1396 if (min_scope <= scope) {
1397 addr = ifa->ifa_local;
1398 break;
1399 }
1400 /* search for large dst subnet for addr */
1401 same = 0;
1402 }
1403 }
1404 }
1405
1406 return same ? addr : 0;
1407 }
1408
1409 /*
1410 * Confirm that local IP address exists using wildcards:
1411 * - net: netns to check, cannot be NULL
1412 * - in_dev: only on this interface, NULL=any interface
1413 * - dst: only in the same subnet as dst, 0=any dst
1414 * - local: address, 0=autoselect the local address
1415 * - scope: maximum allowed scope value for the local address
1416 */
inet_confirm_addr(struct net * net,struct in_device * in_dev,__be32 dst,__be32 local,int scope)1417 __be32 inet_confirm_addr(struct net *net, struct in_device *in_dev,
1418 __be32 dst, __be32 local, int scope)
1419 {
1420 __be32 addr = 0;
1421 struct net_device *dev;
1422
1423 if (in_dev)
1424 return confirm_addr_indev(in_dev, dst, local, scope);
1425
1426 rcu_read_lock();
1427 for_each_netdev_rcu(net, dev) {
1428 in_dev = __in_dev_get_rcu(dev);
1429 if (in_dev) {
1430 addr = confirm_addr_indev(in_dev, dst, local, scope);
1431 if (addr)
1432 break;
1433 }
1434 }
1435 rcu_read_unlock();
1436
1437 return addr;
1438 }
1439 EXPORT_SYMBOL(inet_confirm_addr);
1440
1441 /*
1442 * Device notifier
1443 */
1444
register_inetaddr_notifier(struct notifier_block * nb)1445 int register_inetaddr_notifier(struct notifier_block *nb)
1446 {
1447 return blocking_notifier_chain_register(&inetaddr_chain, nb);
1448 }
1449 EXPORT_SYMBOL(register_inetaddr_notifier);
1450
unregister_inetaddr_notifier(struct notifier_block * nb)1451 int unregister_inetaddr_notifier(struct notifier_block *nb)
1452 {
1453 return blocking_notifier_chain_unregister(&inetaddr_chain, nb);
1454 }
1455 EXPORT_SYMBOL(unregister_inetaddr_notifier);
1456
register_inetaddr_validator_notifier(struct notifier_block * nb)1457 int register_inetaddr_validator_notifier(struct notifier_block *nb)
1458 {
1459 return blocking_notifier_chain_register(&inetaddr_validator_chain, nb);
1460 }
1461 EXPORT_SYMBOL(register_inetaddr_validator_notifier);
1462
unregister_inetaddr_validator_notifier(struct notifier_block * nb)1463 int unregister_inetaddr_validator_notifier(struct notifier_block *nb)
1464 {
1465 return blocking_notifier_chain_unregister(&inetaddr_validator_chain,
1466 nb);
1467 }
1468 EXPORT_SYMBOL(unregister_inetaddr_validator_notifier);
1469
1470 /* Rename ifa_labels for a device name change. Make some effort to preserve
1471 * existing alias numbering and to create unique labels if possible.
1472 */
inetdev_changename(struct net_device * dev,struct in_device * in_dev)1473 static void inetdev_changename(struct net_device *dev, struct in_device *in_dev)
1474 {
1475 struct in_ifaddr *ifa;
1476 int named = 0;
1477
1478 in_dev_for_each_ifa_rtnl(ifa, in_dev) {
1479 char old[IFNAMSIZ], *dot;
1480
1481 memcpy(old, ifa->ifa_label, IFNAMSIZ);
1482 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1483 if (named++ == 0)
1484 goto skip;
1485 dot = strchr(old, ':');
1486 if (!dot) {
1487 sprintf(old, ":%d", named);
1488 dot = old;
1489 }
1490 if (strlen(dot) + strlen(dev->name) < IFNAMSIZ)
1491 strcat(ifa->ifa_label, dot);
1492 else
1493 strcpy(ifa->ifa_label + (IFNAMSIZ - strlen(dot) - 1), dot);
1494 skip:
1495 rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0);
1496 }
1497 }
1498
inetdev_send_gratuitous_arp(struct net_device * dev,struct in_device * in_dev)1499 static void inetdev_send_gratuitous_arp(struct net_device *dev,
1500 struct in_device *in_dev)
1501
1502 {
1503 const struct in_ifaddr *ifa;
1504
1505 in_dev_for_each_ifa_rtnl(ifa, in_dev) {
1506 arp_send(ARPOP_REQUEST, ETH_P_ARP,
1507 ifa->ifa_local, dev,
1508 ifa->ifa_local, NULL,
1509 dev->dev_addr, NULL);
1510 }
1511 }
1512
1513 /* Called only under RTNL semaphore */
1514
inetdev_event(struct notifier_block * this,unsigned long event,void * ptr)1515 static int inetdev_event(struct notifier_block *this, unsigned long event,
1516 void *ptr)
1517 {
1518 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1519 struct in_device *in_dev = __in_dev_get_rtnl(dev);
1520
1521 ASSERT_RTNL();
1522
1523 if (!in_dev) {
1524 if (event == NETDEV_REGISTER) {
1525 in_dev = inetdev_init(dev);
1526 if (IS_ERR(in_dev))
1527 return notifier_from_errno(PTR_ERR(in_dev));
1528 if (dev->flags & IFF_LOOPBACK) {
1529 IN_DEV_CONF_SET(in_dev, NOXFRM, 1);
1530 IN_DEV_CONF_SET(in_dev, NOPOLICY, 1);
1531 }
1532 } else if (event == NETDEV_CHANGEMTU) {
1533 /* Re-enabling IP */
1534 if (inetdev_valid_mtu(dev->mtu))
1535 in_dev = inetdev_init(dev);
1536 }
1537 goto out;
1538 }
1539
1540 switch (event) {
1541 case NETDEV_REGISTER:
1542 pr_debug("%s: bug\n", __func__);
1543 RCU_INIT_POINTER(dev->ip_ptr, NULL);
1544 break;
1545 case NETDEV_UP:
1546 if (!inetdev_valid_mtu(dev->mtu))
1547 break;
1548 if (dev->flags & IFF_LOOPBACK) {
1549 struct in_ifaddr *ifa = inet_alloc_ifa();
1550
1551 if (ifa) {
1552 INIT_HLIST_NODE(&ifa->hash);
1553 ifa->ifa_local =
1554 ifa->ifa_address = htonl(INADDR_LOOPBACK);
1555 ifa->ifa_prefixlen = 8;
1556 ifa->ifa_mask = inet_make_mask(8);
1557 in_dev_hold(in_dev);
1558 ifa->ifa_dev = in_dev;
1559 ifa->ifa_scope = RT_SCOPE_HOST;
1560 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1561 set_ifa_lifetime(ifa, INFINITY_LIFE_TIME,
1562 INFINITY_LIFE_TIME);
1563 ipv4_devconf_setall(in_dev);
1564 neigh_parms_data_state_setall(in_dev->arp_parms);
1565 inet_insert_ifa(ifa);
1566 }
1567 }
1568 ip_mc_up(in_dev);
1569 /* fall through */
1570 case NETDEV_CHANGEADDR:
1571 if (!IN_DEV_ARP_NOTIFY(in_dev))
1572 break;
1573 /* fall through */
1574 case NETDEV_NOTIFY_PEERS:
1575 /* Send gratuitous ARP to notify of link change */
1576 inetdev_send_gratuitous_arp(dev, in_dev);
1577 break;
1578 case NETDEV_DOWN:
1579 ip_mc_down(in_dev);
1580 break;
1581 case NETDEV_PRE_TYPE_CHANGE:
1582 ip_mc_unmap(in_dev);
1583 break;
1584 case NETDEV_POST_TYPE_CHANGE:
1585 ip_mc_remap(in_dev);
1586 break;
1587 case NETDEV_CHANGEMTU:
1588 if (inetdev_valid_mtu(dev->mtu))
1589 break;
1590 /* disable IP when MTU is not enough */
1591 /* fall through */
1592 case NETDEV_UNREGISTER:
1593 inetdev_destroy(in_dev);
1594 break;
1595 case NETDEV_CHANGENAME:
1596 /* Do not notify about label change, this event is
1597 * not interesting to applications using netlink.
1598 */
1599 inetdev_changename(dev, in_dev);
1600
1601 devinet_sysctl_unregister(in_dev);
1602 devinet_sysctl_register(in_dev);
1603 break;
1604 }
1605 out:
1606 return NOTIFY_DONE;
1607 }
1608
1609 static struct notifier_block ip_netdev_notifier = {
1610 .notifier_call = inetdev_event,
1611 };
1612
inet_nlmsg_size(void)1613 static size_t inet_nlmsg_size(void)
1614 {
1615 return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
1616 + nla_total_size(4) /* IFA_ADDRESS */
1617 + nla_total_size(4) /* IFA_LOCAL */
1618 + nla_total_size(4) /* IFA_BROADCAST */
1619 + nla_total_size(IFNAMSIZ) /* IFA_LABEL */
1620 + nla_total_size(4) /* IFA_FLAGS */
1621 + nla_total_size(4) /* IFA_RT_PRIORITY */
1622 + nla_total_size(sizeof(struct ifa_cacheinfo)); /* IFA_CACHEINFO */
1623 }
1624
cstamp_delta(unsigned long cstamp)1625 static inline u32 cstamp_delta(unsigned long cstamp)
1626 {
1627 return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
1628 }
1629
put_cacheinfo(struct sk_buff * skb,unsigned long cstamp,unsigned long tstamp,u32 preferred,u32 valid)1630 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
1631 unsigned long tstamp, u32 preferred, u32 valid)
1632 {
1633 struct ifa_cacheinfo ci;
1634
1635 ci.cstamp = cstamp_delta(cstamp);
1636 ci.tstamp = cstamp_delta(tstamp);
1637 ci.ifa_prefered = preferred;
1638 ci.ifa_valid = valid;
1639
1640 return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
1641 }
1642
inet_fill_ifaddr(struct sk_buff * skb,struct in_ifaddr * ifa,struct inet_fill_args * args)1643 static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa,
1644 struct inet_fill_args *args)
1645 {
1646 struct ifaddrmsg *ifm;
1647 struct nlmsghdr *nlh;
1648 u32 preferred, valid;
1649
1650 nlh = nlmsg_put(skb, args->portid, args->seq, args->event, sizeof(*ifm),
1651 args->flags);
1652 if (!nlh)
1653 return -EMSGSIZE;
1654
1655 ifm = nlmsg_data(nlh);
1656 ifm->ifa_family = AF_INET;
1657 ifm->ifa_prefixlen = ifa->ifa_prefixlen;
1658 ifm->ifa_flags = ifa->ifa_flags;
1659 ifm->ifa_scope = ifa->ifa_scope;
1660 ifm->ifa_index = ifa->ifa_dev->dev->ifindex;
1661
1662 if (args->netnsid >= 0 &&
1663 nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
1664 goto nla_put_failure;
1665
1666 if (!(ifm->ifa_flags & IFA_F_PERMANENT)) {
1667 preferred = ifa->ifa_preferred_lft;
1668 valid = ifa->ifa_valid_lft;
1669 if (preferred != INFINITY_LIFE_TIME) {
1670 long tval = (jiffies - ifa->ifa_tstamp) / HZ;
1671
1672 if (preferred > tval)
1673 preferred -= tval;
1674 else
1675 preferred = 0;
1676 if (valid != INFINITY_LIFE_TIME) {
1677 if (valid > tval)
1678 valid -= tval;
1679 else
1680 valid = 0;
1681 }
1682 }
1683 } else {
1684 preferred = INFINITY_LIFE_TIME;
1685 valid = INFINITY_LIFE_TIME;
1686 }
1687 if ((ifa->ifa_address &&
1688 nla_put_in_addr(skb, IFA_ADDRESS, ifa->ifa_address)) ||
1689 (ifa->ifa_local &&
1690 nla_put_in_addr(skb, IFA_LOCAL, ifa->ifa_local)) ||
1691 (ifa->ifa_broadcast &&
1692 nla_put_in_addr(skb, IFA_BROADCAST, ifa->ifa_broadcast)) ||
1693 (ifa->ifa_label[0] &&
1694 nla_put_string(skb, IFA_LABEL, ifa->ifa_label)) ||
1695 nla_put_u32(skb, IFA_FLAGS, ifa->ifa_flags) ||
1696 (ifa->ifa_rt_priority &&
1697 nla_put_u32(skb, IFA_RT_PRIORITY, ifa->ifa_rt_priority)) ||
1698 put_cacheinfo(skb, ifa->ifa_cstamp, ifa->ifa_tstamp,
1699 preferred, valid))
1700 goto nla_put_failure;
1701
1702 nlmsg_end(skb, nlh);
1703 return 0;
1704
1705 nla_put_failure:
1706 nlmsg_cancel(skb, nlh);
1707 return -EMSGSIZE;
1708 }
1709
inet_valid_dump_ifaddr_req(const struct nlmsghdr * nlh,struct inet_fill_args * fillargs,struct net ** tgt_net,struct sock * sk,struct netlink_callback * cb)1710 static int inet_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
1711 struct inet_fill_args *fillargs,
1712 struct net **tgt_net, struct sock *sk,
1713 struct netlink_callback *cb)
1714 {
1715 struct netlink_ext_ack *extack = cb->extack;
1716 struct nlattr *tb[IFA_MAX+1];
1717 struct ifaddrmsg *ifm;
1718 int err, i;
1719
1720 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
1721 NL_SET_ERR_MSG(extack, "ipv4: Invalid header for address dump request");
1722 return -EINVAL;
1723 }
1724
1725 ifm = nlmsg_data(nlh);
1726 if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
1727 NL_SET_ERR_MSG(extack, "ipv4: Invalid values in header for address dump request");
1728 return -EINVAL;
1729 }
1730
1731 fillargs->ifindex = ifm->ifa_index;
1732 if (fillargs->ifindex) {
1733 cb->answer_flags |= NLM_F_DUMP_FILTERED;
1734 fillargs->flags |= NLM_F_DUMP_FILTERED;
1735 }
1736
1737 err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
1738 ifa_ipv4_policy, extack);
1739 if (err < 0)
1740 return err;
1741
1742 for (i = 0; i <= IFA_MAX; ++i) {
1743 if (!tb[i])
1744 continue;
1745
1746 if (i == IFA_TARGET_NETNSID) {
1747 struct net *net;
1748
1749 fillargs->netnsid = nla_get_s32(tb[i]);
1750
1751 net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
1752 if (IS_ERR(net)) {
1753 fillargs->netnsid = -1;
1754 NL_SET_ERR_MSG(extack, "ipv4: Invalid target network namespace id");
1755 return PTR_ERR(net);
1756 }
1757 *tgt_net = net;
1758 } else {
1759 NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in dump request");
1760 return -EINVAL;
1761 }
1762 }
1763
1764 return 0;
1765 }
1766
in_dev_dump_addr(struct in_device * in_dev,struct sk_buff * skb,struct netlink_callback * cb,int s_ip_idx,struct inet_fill_args * fillargs)1767 static int in_dev_dump_addr(struct in_device *in_dev, struct sk_buff *skb,
1768 struct netlink_callback *cb, int s_ip_idx,
1769 struct inet_fill_args *fillargs)
1770 {
1771 struct in_ifaddr *ifa;
1772 int ip_idx = 0;
1773 int err;
1774
1775 in_dev_for_each_ifa_rtnl(ifa, in_dev) {
1776 if (ip_idx < s_ip_idx) {
1777 ip_idx++;
1778 continue;
1779 }
1780 err = inet_fill_ifaddr(skb, ifa, fillargs);
1781 if (err < 0)
1782 goto done;
1783
1784 nl_dump_check_consistent(cb, nlmsg_hdr(skb));
1785 ip_idx++;
1786 }
1787 err = 0;
1788
1789 done:
1790 cb->args[2] = ip_idx;
1791
1792 return err;
1793 }
1794
inet_dump_ifaddr(struct sk_buff * skb,struct netlink_callback * cb)1795 static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
1796 {
1797 const struct nlmsghdr *nlh = cb->nlh;
1798 struct inet_fill_args fillargs = {
1799 .portid = NETLINK_CB(cb->skb).portid,
1800 .seq = nlh->nlmsg_seq,
1801 .event = RTM_NEWADDR,
1802 .flags = NLM_F_MULTI,
1803 .netnsid = -1,
1804 };
1805 struct net *net = sock_net(skb->sk);
1806 struct net *tgt_net = net;
1807 int h, s_h;
1808 int idx, s_idx;
1809 int s_ip_idx;
1810 struct net_device *dev;
1811 struct in_device *in_dev;
1812 struct hlist_head *head;
1813 int err = 0;
1814
1815 s_h = cb->args[0];
1816 s_idx = idx = cb->args[1];
1817 s_ip_idx = cb->args[2];
1818
1819 if (cb->strict_check) {
1820 err = inet_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
1821 skb->sk, cb);
1822 if (err < 0)
1823 goto put_tgt_net;
1824
1825 err = 0;
1826 if (fillargs.ifindex) {
1827 dev = __dev_get_by_index(tgt_net, fillargs.ifindex);
1828 if (!dev) {
1829 err = -ENODEV;
1830 goto put_tgt_net;
1831 }
1832
1833 in_dev = __in_dev_get_rtnl(dev);
1834 if (in_dev) {
1835 err = in_dev_dump_addr(in_dev, skb, cb, s_ip_idx,
1836 &fillargs);
1837 }
1838 goto put_tgt_net;
1839 }
1840 }
1841
1842 for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
1843 idx = 0;
1844 head = &tgt_net->dev_index_head[h];
1845 rcu_read_lock();
1846 cb->seq = atomic_read(&tgt_net->ipv4.dev_addr_genid) ^
1847 tgt_net->dev_base_seq;
1848 hlist_for_each_entry_rcu(dev, head, index_hlist) {
1849 if (idx < s_idx)
1850 goto cont;
1851 if (h > s_h || idx > s_idx)
1852 s_ip_idx = 0;
1853 in_dev = __in_dev_get_rcu(dev);
1854 if (!in_dev)
1855 goto cont;
1856
1857 err = in_dev_dump_addr(in_dev, skb, cb, s_ip_idx,
1858 &fillargs);
1859 if (err < 0) {
1860 rcu_read_unlock();
1861 goto done;
1862 }
1863 cont:
1864 idx++;
1865 }
1866 rcu_read_unlock();
1867 }
1868
1869 done:
1870 cb->args[0] = h;
1871 cb->args[1] = idx;
1872 put_tgt_net:
1873 if (fillargs.netnsid >= 0)
1874 put_net(tgt_net);
1875
1876 return skb->len ? : err;
1877 }
1878
rtmsg_ifa(int event,struct in_ifaddr * ifa,struct nlmsghdr * nlh,u32 portid)1879 static void rtmsg_ifa(int event, struct in_ifaddr *ifa, struct nlmsghdr *nlh,
1880 u32 portid)
1881 {
1882 struct inet_fill_args fillargs = {
1883 .portid = portid,
1884 .seq = nlh ? nlh->nlmsg_seq : 0,
1885 .event = event,
1886 .flags = 0,
1887 .netnsid = -1,
1888 };
1889 struct sk_buff *skb;
1890 int err = -ENOBUFS;
1891 struct net *net;
1892
1893 net = dev_net(ifa->ifa_dev->dev);
1894 skb = nlmsg_new(inet_nlmsg_size(), GFP_KERNEL);
1895 if (!skb)
1896 goto errout;
1897
1898 err = inet_fill_ifaddr(skb, ifa, &fillargs);
1899 if (err < 0) {
1900 /* -EMSGSIZE implies BUG in inet_nlmsg_size() */
1901 WARN_ON(err == -EMSGSIZE);
1902 kfree_skb(skb);
1903 goto errout;
1904 }
1905 rtnl_notify(skb, net, portid, RTNLGRP_IPV4_IFADDR, nlh, GFP_KERNEL);
1906 return;
1907 errout:
1908 if (err < 0)
1909 rtnl_set_sk_err(net, RTNLGRP_IPV4_IFADDR, err);
1910 }
1911
inet_get_link_af_size(const struct net_device * dev,u32 ext_filter_mask)1912 static size_t inet_get_link_af_size(const struct net_device *dev,
1913 u32 ext_filter_mask)
1914 {
1915 struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr);
1916
1917 if (!in_dev)
1918 return 0;
1919
1920 return nla_total_size(IPV4_DEVCONF_MAX * 4); /* IFLA_INET_CONF */
1921 }
1922
inet_fill_link_af(struct sk_buff * skb,const struct net_device * dev,u32 ext_filter_mask)1923 static int inet_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
1924 u32 ext_filter_mask)
1925 {
1926 struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr);
1927 struct nlattr *nla;
1928 int i;
1929
1930 if (!in_dev)
1931 return -ENODATA;
1932
1933 nla = nla_reserve(skb, IFLA_INET_CONF, IPV4_DEVCONF_MAX * 4);
1934 if (!nla)
1935 return -EMSGSIZE;
1936
1937 for (i = 0; i < IPV4_DEVCONF_MAX; i++)
1938 ((u32 *) nla_data(nla))[i] = in_dev->cnf.data[i];
1939
1940 return 0;
1941 }
1942
1943 static const struct nla_policy inet_af_policy[IFLA_INET_MAX+1] = {
1944 [IFLA_INET_CONF] = { .type = NLA_NESTED },
1945 };
1946
inet_validate_link_af(const struct net_device * dev,const struct nlattr * nla)1947 static int inet_validate_link_af(const struct net_device *dev,
1948 const struct nlattr *nla)
1949 {
1950 struct nlattr *a, *tb[IFLA_INET_MAX+1];
1951 int err, rem;
1952
1953 if (dev && !__in_dev_get_rcu(dev))
1954 return -EAFNOSUPPORT;
1955
1956 err = nla_parse_nested_deprecated(tb, IFLA_INET_MAX, nla,
1957 inet_af_policy, NULL);
1958 if (err < 0)
1959 return err;
1960
1961 if (tb[IFLA_INET_CONF]) {
1962 nla_for_each_nested(a, tb[IFLA_INET_CONF], rem) {
1963 int cfgid = nla_type(a);
1964
1965 if (nla_len(a) < 4)
1966 return -EINVAL;
1967
1968 if (cfgid <= 0 || cfgid > IPV4_DEVCONF_MAX)
1969 return -EINVAL;
1970 }
1971 }
1972
1973 return 0;
1974 }
1975
inet_set_link_af(struct net_device * dev,const struct nlattr * nla)1976 static int inet_set_link_af(struct net_device *dev, const struct nlattr *nla)
1977 {
1978 struct in_device *in_dev = __in_dev_get_rcu(dev);
1979 struct nlattr *a, *tb[IFLA_INET_MAX+1];
1980 int rem;
1981
1982 if (!in_dev)
1983 return -EAFNOSUPPORT;
1984
1985 if (nla_parse_nested_deprecated(tb, IFLA_INET_MAX, nla, NULL, NULL) < 0)
1986 BUG();
1987
1988 if (tb[IFLA_INET_CONF]) {
1989 nla_for_each_nested(a, tb[IFLA_INET_CONF], rem)
1990 ipv4_devconf_set(in_dev, nla_type(a), nla_get_u32(a));
1991 }
1992
1993 return 0;
1994 }
1995
inet_netconf_msgsize_devconf(int type)1996 static int inet_netconf_msgsize_devconf(int type)
1997 {
1998 int size = NLMSG_ALIGN(sizeof(struct netconfmsg))
1999 + nla_total_size(4); /* NETCONFA_IFINDEX */
2000 bool all = false;
2001
2002 if (type == NETCONFA_ALL)
2003 all = true;
2004
2005 if (all || type == NETCONFA_FORWARDING)
2006 size += nla_total_size(4);
2007 if (all || type == NETCONFA_RP_FILTER)
2008 size += nla_total_size(4);
2009 if (all || type == NETCONFA_MC_FORWARDING)
2010 size += nla_total_size(4);
2011 if (all || type == NETCONFA_BC_FORWARDING)
2012 size += nla_total_size(4);
2013 if (all || type == NETCONFA_PROXY_NEIGH)
2014 size += nla_total_size(4);
2015 if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
2016 size += nla_total_size(4);
2017
2018 return size;
2019 }
2020
inet_netconf_fill_devconf(struct sk_buff * skb,int ifindex,struct ipv4_devconf * devconf,u32 portid,u32 seq,int event,unsigned int flags,int type)2021 static int inet_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
2022 struct ipv4_devconf *devconf, u32 portid,
2023 u32 seq, int event, unsigned int flags,
2024 int type)
2025 {
2026 struct nlmsghdr *nlh;
2027 struct netconfmsg *ncm;
2028 bool all = false;
2029
2030 nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
2031 flags);
2032 if (!nlh)
2033 return -EMSGSIZE;
2034
2035 if (type == NETCONFA_ALL)
2036 all = true;
2037
2038 ncm = nlmsg_data(nlh);
2039 ncm->ncm_family = AF_INET;
2040
2041 if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
2042 goto nla_put_failure;
2043
2044 if (!devconf)
2045 goto out;
2046
2047 if ((all || type == NETCONFA_FORWARDING) &&
2048 nla_put_s32(skb, NETCONFA_FORWARDING,
2049 IPV4_DEVCONF(*devconf, FORWARDING)) < 0)
2050 goto nla_put_failure;
2051 if ((all || type == NETCONFA_RP_FILTER) &&
2052 nla_put_s32(skb, NETCONFA_RP_FILTER,
2053 IPV4_DEVCONF(*devconf, RP_FILTER)) < 0)
2054 goto nla_put_failure;
2055 if ((all || type == NETCONFA_MC_FORWARDING) &&
2056 nla_put_s32(skb, NETCONFA_MC_FORWARDING,
2057 IPV4_DEVCONF(*devconf, MC_FORWARDING)) < 0)
2058 goto nla_put_failure;
2059 if ((all || type == NETCONFA_BC_FORWARDING) &&
2060 nla_put_s32(skb, NETCONFA_BC_FORWARDING,
2061 IPV4_DEVCONF(*devconf, BC_FORWARDING)) < 0)
2062 goto nla_put_failure;
2063 if ((all || type == NETCONFA_PROXY_NEIGH) &&
2064 nla_put_s32(skb, NETCONFA_PROXY_NEIGH,
2065 IPV4_DEVCONF(*devconf, PROXY_ARP)) < 0)
2066 goto nla_put_failure;
2067 if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
2068 nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
2069 IPV4_DEVCONF(*devconf, IGNORE_ROUTES_WITH_LINKDOWN)) < 0)
2070 goto nla_put_failure;
2071
2072 out:
2073 nlmsg_end(skb, nlh);
2074 return 0;
2075
2076 nla_put_failure:
2077 nlmsg_cancel(skb, nlh);
2078 return -EMSGSIZE;
2079 }
2080
inet_netconf_notify_devconf(struct net * net,int event,int type,int ifindex,struct ipv4_devconf * devconf)2081 void inet_netconf_notify_devconf(struct net *net, int event, int type,
2082 int ifindex, struct ipv4_devconf *devconf)
2083 {
2084 struct sk_buff *skb;
2085 int err = -ENOBUFS;
2086
2087 skb = nlmsg_new(inet_netconf_msgsize_devconf(type), GFP_KERNEL);
2088 if (!skb)
2089 goto errout;
2090
2091 err = inet_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
2092 event, 0, type);
2093 if (err < 0) {
2094 /* -EMSGSIZE implies BUG in inet_netconf_msgsize_devconf() */
2095 WARN_ON(err == -EMSGSIZE);
2096 kfree_skb(skb);
2097 goto errout;
2098 }
2099 rtnl_notify(skb, net, 0, RTNLGRP_IPV4_NETCONF, NULL, GFP_KERNEL);
2100 return;
2101 errout:
2102 if (err < 0)
2103 rtnl_set_sk_err(net, RTNLGRP_IPV4_NETCONF, err);
2104 }
2105
2106 static const struct nla_policy devconf_ipv4_policy[NETCONFA_MAX+1] = {
2107 [NETCONFA_IFINDEX] = { .len = sizeof(int) },
2108 [NETCONFA_FORWARDING] = { .len = sizeof(int) },
2109 [NETCONFA_RP_FILTER] = { .len = sizeof(int) },
2110 [NETCONFA_PROXY_NEIGH] = { .len = sizeof(int) },
2111 [NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN] = { .len = sizeof(int) },
2112 };
2113
inet_netconf_valid_get_req(struct sk_buff * skb,const struct nlmsghdr * nlh,struct nlattr ** tb,struct netlink_ext_ack * extack)2114 static int inet_netconf_valid_get_req(struct sk_buff *skb,
2115 const struct nlmsghdr *nlh,
2116 struct nlattr **tb,
2117 struct netlink_ext_ack *extack)
2118 {
2119 int i, err;
2120
2121 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
2122 NL_SET_ERR_MSG(extack, "ipv4: Invalid header for netconf get request");
2123 return -EINVAL;
2124 }
2125
2126 if (!netlink_strict_get_check(skb))
2127 return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
2128 tb, NETCONFA_MAX,
2129 devconf_ipv4_policy, extack);
2130
2131 err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
2132 tb, NETCONFA_MAX,
2133 devconf_ipv4_policy, extack);
2134 if (err)
2135 return err;
2136
2137 for (i = 0; i <= NETCONFA_MAX; i++) {
2138 if (!tb[i])
2139 continue;
2140
2141 switch (i) {
2142 case NETCONFA_IFINDEX:
2143 break;
2144 default:
2145 NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in netconf get request");
2146 return -EINVAL;
2147 }
2148 }
2149
2150 return 0;
2151 }
2152
inet_netconf_get_devconf(struct sk_buff * in_skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)2153 static int inet_netconf_get_devconf(struct sk_buff *in_skb,
2154 struct nlmsghdr *nlh,
2155 struct netlink_ext_ack *extack)
2156 {
2157 struct net *net = sock_net(in_skb->sk);
2158 struct nlattr *tb[NETCONFA_MAX+1];
2159 struct sk_buff *skb;
2160 struct ipv4_devconf *devconf;
2161 struct in_device *in_dev;
2162 struct net_device *dev;
2163 int ifindex;
2164 int err;
2165
2166 err = inet_netconf_valid_get_req(in_skb, nlh, tb, extack);
2167 if (err)
2168 goto errout;
2169
2170 err = -EINVAL;
2171 if (!tb[NETCONFA_IFINDEX])
2172 goto errout;
2173
2174 ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
2175 switch (ifindex) {
2176 case NETCONFA_IFINDEX_ALL:
2177 devconf = net->ipv4.devconf_all;
2178 break;
2179 case NETCONFA_IFINDEX_DEFAULT:
2180 devconf = net->ipv4.devconf_dflt;
2181 break;
2182 default:
2183 dev = __dev_get_by_index(net, ifindex);
2184 if (!dev)
2185 goto errout;
2186 in_dev = __in_dev_get_rtnl(dev);
2187 if (!in_dev)
2188 goto errout;
2189 devconf = &in_dev->cnf;
2190 break;
2191 }
2192
2193 err = -ENOBUFS;
2194 skb = nlmsg_new(inet_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
2195 if (!skb)
2196 goto errout;
2197
2198 err = inet_netconf_fill_devconf(skb, ifindex, devconf,
2199 NETLINK_CB(in_skb).portid,
2200 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
2201 NETCONFA_ALL);
2202 if (err < 0) {
2203 /* -EMSGSIZE implies BUG in inet_netconf_msgsize_devconf() */
2204 WARN_ON(err == -EMSGSIZE);
2205 kfree_skb(skb);
2206 goto errout;
2207 }
2208 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
2209 errout:
2210 return err;
2211 }
2212
inet_netconf_dump_devconf(struct sk_buff * skb,struct netlink_callback * cb)2213 static int inet_netconf_dump_devconf(struct sk_buff *skb,
2214 struct netlink_callback *cb)
2215 {
2216 const struct nlmsghdr *nlh = cb->nlh;
2217 struct net *net = sock_net(skb->sk);
2218 int h, s_h;
2219 int idx, s_idx;
2220 struct net_device *dev;
2221 struct in_device *in_dev;
2222 struct hlist_head *head;
2223
2224 if (cb->strict_check) {
2225 struct netlink_ext_ack *extack = cb->extack;
2226 struct netconfmsg *ncm;
2227
2228 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
2229 NL_SET_ERR_MSG(extack, "ipv4: Invalid header for netconf dump request");
2230 return -EINVAL;
2231 }
2232
2233 if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
2234 NL_SET_ERR_MSG(extack, "ipv4: Invalid data after header in netconf dump request");
2235 return -EINVAL;
2236 }
2237 }
2238
2239 s_h = cb->args[0];
2240 s_idx = idx = cb->args[1];
2241
2242 for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
2243 idx = 0;
2244 head = &net->dev_index_head[h];
2245 rcu_read_lock();
2246 cb->seq = atomic_read(&net->ipv4.dev_addr_genid) ^
2247 net->dev_base_seq;
2248 hlist_for_each_entry_rcu(dev, head, index_hlist) {
2249 if (idx < s_idx)
2250 goto cont;
2251 in_dev = __in_dev_get_rcu(dev);
2252 if (!in_dev)
2253 goto cont;
2254
2255 if (inet_netconf_fill_devconf(skb, dev->ifindex,
2256 &in_dev->cnf,
2257 NETLINK_CB(cb->skb).portid,
2258 nlh->nlmsg_seq,
2259 RTM_NEWNETCONF,
2260 NLM_F_MULTI,
2261 NETCONFA_ALL) < 0) {
2262 rcu_read_unlock();
2263 goto done;
2264 }
2265 nl_dump_check_consistent(cb, nlmsg_hdr(skb));
2266 cont:
2267 idx++;
2268 }
2269 rcu_read_unlock();
2270 }
2271 if (h == NETDEV_HASHENTRIES) {
2272 if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
2273 net->ipv4.devconf_all,
2274 NETLINK_CB(cb->skb).portid,
2275 nlh->nlmsg_seq,
2276 RTM_NEWNETCONF, NLM_F_MULTI,
2277 NETCONFA_ALL) < 0)
2278 goto done;
2279 else
2280 h++;
2281 }
2282 if (h == NETDEV_HASHENTRIES + 1) {
2283 if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
2284 net->ipv4.devconf_dflt,
2285 NETLINK_CB(cb->skb).portid,
2286 nlh->nlmsg_seq,
2287 RTM_NEWNETCONF, NLM_F_MULTI,
2288 NETCONFA_ALL) < 0)
2289 goto done;
2290 else
2291 h++;
2292 }
2293 done:
2294 cb->args[0] = h;
2295 cb->args[1] = idx;
2296
2297 return skb->len;
2298 }
2299
2300 #ifdef CONFIG_SYSCTL
2301
devinet_copy_dflt_conf(struct net * net,int i)2302 static void devinet_copy_dflt_conf(struct net *net, int i)
2303 {
2304 struct net_device *dev;
2305
2306 rcu_read_lock();
2307 for_each_netdev_rcu(net, dev) {
2308 struct in_device *in_dev;
2309
2310 in_dev = __in_dev_get_rcu(dev);
2311 if (in_dev && !test_bit(i, in_dev->cnf.state))
2312 in_dev->cnf.data[i] = net->ipv4.devconf_dflt->data[i];
2313 }
2314 rcu_read_unlock();
2315 }
2316
2317 /* called with RTNL locked */
inet_forward_change(struct net * net)2318 static void inet_forward_change(struct net *net)
2319 {
2320 struct net_device *dev;
2321 int on = IPV4_DEVCONF_ALL(net, FORWARDING);
2322
2323 IPV4_DEVCONF_ALL(net, ACCEPT_REDIRECTS) = !on;
2324 IPV4_DEVCONF_DFLT(net, FORWARDING) = on;
2325 inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
2326 NETCONFA_FORWARDING,
2327 NETCONFA_IFINDEX_ALL,
2328 net->ipv4.devconf_all);
2329 inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
2330 NETCONFA_FORWARDING,
2331 NETCONFA_IFINDEX_DEFAULT,
2332 net->ipv4.devconf_dflt);
2333
2334 for_each_netdev(net, dev) {
2335 struct in_device *in_dev;
2336
2337 if (on)
2338 dev_disable_lro(dev);
2339
2340 in_dev = __in_dev_get_rtnl(dev);
2341 if (in_dev) {
2342 IN_DEV_CONF_SET(in_dev, FORWARDING, on);
2343 inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
2344 NETCONFA_FORWARDING,
2345 dev->ifindex, &in_dev->cnf);
2346 }
2347 }
2348 }
2349
devinet_conf_ifindex(struct net * net,struct ipv4_devconf * cnf)2350 static int devinet_conf_ifindex(struct net *net, struct ipv4_devconf *cnf)
2351 {
2352 if (cnf == net->ipv4.devconf_dflt)
2353 return NETCONFA_IFINDEX_DEFAULT;
2354 else if (cnf == net->ipv4.devconf_all)
2355 return NETCONFA_IFINDEX_ALL;
2356 else {
2357 struct in_device *idev
2358 = container_of(cnf, struct in_device, cnf);
2359 return idev->dev->ifindex;
2360 }
2361 }
2362
devinet_conf_proc(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)2363 static int devinet_conf_proc(struct ctl_table *ctl, int write,
2364 void __user *buffer,
2365 size_t *lenp, loff_t *ppos)
2366 {
2367 int old_value = *(int *)ctl->data;
2368 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
2369 int new_value = *(int *)ctl->data;
2370
2371 if (write) {
2372 struct ipv4_devconf *cnf = ctl->extra1;
2373 struct net *net = ctl->extra2;
2374 int i = (int *)ctl->data - cnf->data;
2375 int ifindex;
2376
2377 set_bit(i, cnf->state);
2378
2379 if (cnf == net->ipv4.devconf_dflt)
2380 devinet_copy_dflt_conf(net, i);
2381 if (i == IPV4_DEVCONF_ACCEPT_LOCAL - 1 ||
2382 i == IPV4_DEVCONF_ROUTE_LOCALNET - 1)
2383 if ((new_value == 0) && (old_value != 0))
2384 rt_cache_flush(net);
2385
2386 if (i == IPV4_DEVCONF_BC_FORWARDING - 1 &&
2387 new_value != old_value)
2388 rt_cache_flush(net);
2389
2390 if (i == IPV4_DEVCONF_RP_FILTER - 1 &&
2391 new_value != old_value) {
2392 ifindex = devinet_conf_ifindex(net, cnf);
2393 inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
2394 NETCONFA_RP_FILTER,
2395 ifindex, cnf);
2396 }
2397 if (i == IPV4_DEVCONF_PROXY_ARP - 1 &&
2398 new_value != old_value) {
2399 ifindex = devinet_conf_ifindex(net, cnf);
2400 inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
2401 NETCONFA_PROXY_NEIGH,
2402 ifindex, cnf);
2403 }
2404 if (i == IPV4_DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN - 1 &&
2405 new_value != old_value) {
2406 ifindex = devinet_conf_ifindex(net, cnf);
2407 inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
2408 NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
2409 ifindex, cnf);
2410 }
2411 }
2412
2413 return ret;
2414 }
2415
devinet_sysctl_forward(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)2416 static int devinet_sysctl_forward(struct ctl_table *ctl, int write,
2417 void __user *buffer,
2418 size_t *lenp, loff_t *ppos)
2419 {
2420 int *valp = ctl->data;
2421 int val = *valp;
2422 loff_t pos = *ppos;
2423 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
2424
2425 if (write && *valp != val) {
2426 struct net *net = ctl->extra2;
2427
2428 if (valp != &IPV4_DEVCONF_DFLT(net, FORWARDING)) {
2429 if (!rtnl_trylock()) {
2430 /* Restore the original values before restarting */
2431 *valp = val;
2432 *ppos = pos;
2433 return restart_syscall();
2434 }
2435 if (valp == &IPV4_DEVCONF_ALL(net, FORWARDING)) {
2436 inet_forward_change(net);
2437 } else {
2438 struct ipv4_devconf *cnf = ctl->extra1;
2439 struct in_device *idev =
2440 container_of(cnf, struct in_device, cnf);
2441 if (*valp)
2442 dev_disable_lro(idev->dev);
2443 inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
2444 NETCONFA_FORWARDING,
2445 idev->dev->ifindex,
2446 cnf);
2447 }
2448 rtnl_unlock();
2449 rt_cache_flush(net);
2450 } else
2451 inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
2452 NETCONFA_FORWARDING,
2453 NETCONFA_IFINDEX_DEFAULT,
2454 net->ipv4.devconf_dflt);
2455 }
2456
2457 return ret;
2458 }
2459
ipv4_doint_and_flush(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)2460 static int ipv4_doint_and_flush(struct ctl_table *ctl, int write,
2461 void __user *buffer,
2462 size_t *lenp, loff_t *ppos)
2463 {
2464 int *valp = ctl->data;
2465 int val = *valp;
2466 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
2467 struct net *net = ctl->extra2;
2468
2469 if (write && *valp != val)
2470 rt_cache_flush(net);
2471
2472 return ret;
2473 }
2474
2475 #define DEVINET_SYSCTL_ENTRY(attr, name, mval, proc) \
2476 { \
2477 .procname = name, \
2478 .data = ipv4_devconf.data + \
2479 IPV4_DEVCONF_ ## attr - 1, \
2480 .maxlen = sizeof(int), \
2481 .mode = mval, \
2482 .proc_handler = proc, \
2483 .extra1 = &ipv4_devconf, \
2484 }
2485
2486 #define DEVINET_SYSCTL_RW_ENTRY(attr, name) \
2487 DEVINET_SYSCTL_ENTRY(attr, name, 0644, devinet_conf_proc)
2488
2489 #define DEVINET_SYSCTL_RO_ENTRY(attr, name) \
2490 DEVINET_SYSCTL_ENTRY(attr, name, 0444, devinet_conf_proc)
2491
2492 #define DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, proc) \
2493 DEVINET_SYSCTL_ENTRY(attr, name, 0644, proc)
2494
2495 #define DEVINET_SYSCTL_FLUSHING_ENTRY(attr, name) \
2496 DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, ipv4_doint_and_flush)
2497
2498 static struct devinet_sysctl_table {
2499 struct ctl_table_header *sysctl_header;
2500 struct ctl_table devinet_vars[__IPV4_DEVCONF_MAX];
2501 } devinet_sysctl = {
2502 .devinet_vars = {
2503 DEVINET_SYSCTL_COMPLEX_ENTRY(FORWARDING, "forwarding",
2504 devinet_sysctl_forward),
2505 DEVINET_SYSCTL_RO_ENTRY(MC_FORWARDING, "mc_forwarding"),
2506 DEVINET_SYSCTL_RW_ENTRY(BC_FORWARDING, "bc_forwarding"),
2507
2508 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_REDIRECTS, "accept_redirects"),
2509 DEVINET_SYSCTL_RW_ENTRY(SECURE_REDIRECTS, "secure_redirects"),
2510 DEVINET_SYSCTL_RW_ENTRY(SHARED_MEDIA, "shared_media"),
2511 DEVINET_SYSCTL_RW_ENTRY(RP_FILTER, "rp_filter"),
2512 DEVINET_SYSCTL_RW_ENTRY(SEND_REDIRECTS, "send_redirects"),
2513 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_SOURCE_ROUTE,
2514 "accept_source_route"),
2515 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_LOCAL, "accept_local"),
2516 DEVINET_SYSCTL_RW_ENTRY(SRC_VMARK, "src_valid_mark"),
2517 DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP, "proxy_arp"),
2518 DEVINET_SYSCTL_RW_ENTRY(MEDIUM_ID, "medium_id"),
2519 DEVINET_SYSCTL_RW_ENTRY(BOOTP_RELAY, "bootp_relay"),
2520 DEVINET_SYSCTL_RW_ENTRY(LOG_MARTIANS, "log_martians"),
2521 DEVINET_SYSCTL_RW_ENTRY(TAG, "tag"),
2522 DEVINET_SYSCTL_RW_ENTRY(ARPFILTER, "arp_filter"),
2523 DEVINET_SYSCTL_RW_ENTRY(ARP_ANNOUNCE, "arp_announce"),
2524 DEVINET_SYSCTL_RW_ENTRY(ARP_IGNORE, "arp_ignore"),
2525 DEVINET_SYSCTL_RW_ENTRY(ARP_ACCEPT, "arp_accept"),
2526 DEVINET_SYSCTL_RW_ENTRY(ARP_NOTIFY, "arp_notify"),
2527 DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP_PVLAN, "proxy_arp_pvlan"),
2528 DEVINET_SYSCTL_RW_ENTRY(FORCE_IGMP_VERSION,
2529 "force_igmp_version"),
2530 DEVINET_SYSCTL_RW_ENTRY(IGMPV2_UNSOLICITED_REPORT_INTERVAL,
2531 "igmpv2_unsolicited_report_interval"),
2532 DEVINET_SYSCTL_RW_ENTRY(IGMPV3_UNSOLICITED_REPORT_INTERVAL,
2533 "igmpv3_unsolicited_report_interval"),
2534 DEVINET_SYSCTL_RW_ENTRY(IGNORE_ROUTES_WITH_LINKDOWN,
2535 "ignore_routes_with_linkdown"),
2536 DEVINET_SYSCTL_RW_ENTRY(DROP_GRATUITOUS_ARP,
2537 "drop_gratuitous_arp"),
2538
2539 DEVINET_SYSCTL_FLUSHING_ENTRY(NOXFRM, "disable_xfrm"),
2540 DEVINET_SYSCTL_FLUSHING_ENTRY(NOPOLICY, "disable_policy"),
2541 DEVINET_SYSCTL_FLUSHING_ENTRY(PROMOTE_SECONDARIES,
2542 "promote_secondaries"),
2543 DEVINET_SYSCTL_FLUSHING_ENTRY(ROUTE_LOCALNET,
2544 "route_localnet"),
2545 DEVINET_SYSCTL_FLUSHING_ENTRY(DROP_UNICAST_IN_L2_MULTICAST,
2546 "drop_unicast_in_l2_multicast"),
2547 },
2548 };
2549
__devinet_sysctl_register(struct net * net,char * dev_name,int ifindex,struct ipv4_devconf * p)2550 static int __devinet_sysctl_register(struct net *net, char *dev_name,
2551 int ifindex, struct ipv4_devconf *p)
2552 {
2553 int i;
2554 struct devinet_sysctl_table *t;
2555 char path[sizeof("net/ipv4/conf/") + IFNAMSIZ];
2556
2557 t = kmemdup(&devinet_sysctl, sizeof(*t), GFP_KERNEL);
2558 if (!t)
2559 goto out;
2560
2561 for (i = 0; i < ARRAY_SIZE(t->devinet_vars) - 1; i++) {
2562 t->devinet_vars[i].data += (char *)p - (char *)&ipv4_devconf;
2563 t->devinet_vars[i].extra1 = p;
2564 t->devinet_vars[i].extra2 = net;
2565 }
2566
2567 snprintf(path, sizeof(path), "net/ipv4/conf/%s", dev_name);
2568
2569 t->sysctl_header = register_net_sysctl(net, path, t->devinet_vars);
2570 if (!t->sysctl_header)
2571 goto free;
2572
2573 p->sysctl = t;
2574
2575 inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
2576 ifindex, p);
2577 return 0;
2578
2579 free:
2580 kfree(t);
2581 out:
2582 return -ENOBUFS;
2583 }
2584
__devinet_sysctl_unregister(struct net * net,struct ipv4_devconf * cnf,int ifindex)2585 static void __devinet_sysctl_unregister(struct net *net,
2586 struct ipv4_devconf *cnf, int ifindex)
2587 {
2588 struct devinet_sysctl_table *t = cnf->sysctl;
2589
2590 if (t) {
2591 cnf->sysctl = NULL;
2592 unregister_net_sysctl_table(t->sysctl_header);
2593 kfree(t);
2594 }
2595
2596 inet_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
2597 }
2598
devinet_sysctl_register(struct in_device * idev)2599 static int devinet_sysctl_register(struct in_device *idev)
2600 {
2601 int err;
2602
2603 if (!sysctl_dev_name_is_allowed(idev->dev->name))
2604 return -EINVAL;
2605
2606 err = neigh_sysctl_register(idev->dev, idev->arp_parms, NULL);
2607 if (err)
2608 return err;
2609 err = __devinet_sysctl_register(dev_net(idev->dev), idev->dev->name,
2610 idev->dev->ifindex, &idev->cnf);
2611 if (err)
2612 neigh_sysctl_unregister(idev->arp_parms);
2613 return err;
2614 }
2615
devinet_sysctl_unregister(struct in_device * idev)2616 static void devinet_sysctl_unregister(struct in_device *idev)
2617 {
2618 struct net *net = dev_net(idev->dev);
2619
2620 __devinet_sysctl_unregister(net, &idev->cnf, idev->dev->ifindex);
2621 neigh_sysctl_unregister(idev->arp_parms);
2622 }
2623
2624 static struct ctl_table ctl_forward_entry[] = {
2625 {
2626 .procname = "ip_forward",
2627 .data = &ipv4_devconf.data[
2628 IPV4_DEVCONF_FORWARDING - 1],
2629 .maxlen = sizeof(int),
2630 .mode = 0644,
2631 .proc_handler = devinet_sysctl_forward,
2632 .extra1 = &ipv4_devconf,
2633 .extra2 = &init_net,
2634 },
2635 { },
2636 };
2637 #endif
2638
devinet_init_net(struct net * net)2639 static __net_init int devinet_init_net(struct net *net)
2640 {
2641 int err;
2642 struct ipv4_devconf *all, *dflt;
2643 #ifdef CONFIG_SYSCTL
2644 struct ctl_table *tbl;
2645 struct ctl_table_header *forw_hdr;
2646 #endif
2647
2648 err = -ENOMEM;
2649 all = kmemdup(&ipv4_devconf, sizeof(ipv4_devconf), GFP_KERNEL);
2650 if (!all)
2651 goto err_alloc_all;
2652
2653 dflt = kmemdup(&ipv4_devconf_dflt, sizeof(ipv4_devconf_dflt), GFP_KERNEL);
2654 if (!dflt)
2655 goto err_alloc_dflt;
2656
2657 #ifdef CONFIG_SYSCTL
2658 tbl = kmemdup(ctl_forward_entry, sizeof(ctl_forward_entry), GFP_KERNEL);
2659 if (!tbl)
2660 goto err_alloc_ctl;
2661
2662 tbl[0].data = &all->data[IPV4_DEVCONF_FORWARDING - 1];
2663 tbl[0].extra1 = all;
2664 tbl[0].extra2 = net;
2665 #endif
2666
2667 if ((!IS_ENABLED(CONFIG_SYSCTL) ||
2668 sysctl_devconf_inherit_init_net != 2) &&
2669 !net_eq(net, &init_net)) {
2670 memcpy(all, init_net.ipv4.devconf_all, sizeof(ipv4_devconf));
2671 memcpy(dflt, init_net.ipv4.devconf_dflt, sizeof(ipv4_devconf_dflt));
2672 }
2673
2674 #ifdef CONFIG_SYSCTL
2675 err = __devinet_sysctl_register(net, "all", NETCONFA_IFINDEX_ALL, all);
2676 if (err < 0)
2677 goto err_reg_all;
2678
2679 err = __devinet_sysctl_register(net, "default",
2680 NETCONFA_IFINDEX_DEFAULT, dflt);
2681 if (err < 0)
2682 goto err_reg_dflt;
2683
2684 err = -ENOMEM;
2685 forw_hdr = register_net_sysctl(net, "net/ipv4", tbl);
2686 if (!forw_hdr)
2687 goto err_reg_ctl;
2688 net->ipv4.forw_hdr = forw_hdr;
2689 #endif
2690
2691 net->ipv4.devconf_all = all;
2692 net->ipv4.devconf_dflt = dflt;
2693 return 0;
2694
2695 #ifdef CONFIG_SYSCTL
2696 err_reg_ctl:
2697 __devinet_sysctl_unregister(net, dflt, NETCONFA_IFINDEX_DEFAULT);
2698 err_reg_dflt:
2699 __devinet_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
2700 err_reg_all:
2701 kfree(tbl);
2702 err_alloc_ctl:
2703 #endif
2704 kfree(dflt);
2705 err_alloc_dflt:
2706 kfree(all);
2707 err_alloc_all:
2708 return err;
2709 }
2710
devinet_exit_net(struct net * net)2711 static __net_exit void devinet_exit_net(struct net *net)
2712 {
2713 #ifdef CONFIG_SYSCTL
2714 struct ctl_table *tbl;
2715
2716 tbl = net->ipv4.forw_hdr->ctl_table_arg;
2717 unregister_net_sysctl_table(net->ipv4.forw_hdr);
2718 __devinet_sysctl_unregister(net, net->ipv4.devconf_dflt,
2719 NETCONFA_IFINDEX_DEFAULT);
2720 __devinet_sysctl_unregister(net, net->ipv4.devconf_all,
2721 NETCONFA_IFINDEX_ALL);
2722 kfree(tbl);
2723 #endif
2724 kfree(net->ipv4.devconf_dflt);
2725 kfree(net->ipv4.devconf_all);
2726 }
2727
2728 static __net_initdata struct pernet_operations devinet_ops = {
2729 .init = devinet_init_net,
2730 .exit = devinet_exit_net,
2731 };
2732
2733 static struct rtnl_af_ops inet_af_ops __read_mostly = {
2734 .family = AF_INET,
2735 .fill_link_af = inet_fill_link_af,
2736 .get_link_af_size = inet_get_link_af_size,
2737 .validate_link_af = inet_validate_link_af,
2738 .set_link_af = inet_set_link_af,
2739 };
2740
devinet_init(void)2741 void __init devinet_init(void)
2742 {
2743 int i;
2744
2745 for (i = 0; i < IN4_ADDR_HSIZE; i++)
2746 INIT_HLIST_HEAD(&inet_addr_lst[i]);
2747
2748 register_pernet_subsys(&devinet_ops);
2749
2750 register_gifconf(PF_INET, inet_gifconf);
2751 register_netdevice_notifier(&ip_netdev_notifier);
2752
2753 queue_delayed_work(system_power_efficient_wq, &check_lifetime_work, 0);
2754
2755 rtnl_af_register(&inet_af_ops);
2756
2757 rtnl_register(PF_INET, RTM_NEWADDR, inet_rtm_newaddr, NULL, 0);
2758 rtnl_register(PF_INET, RTM_DELADDR, inet_rtm_deladdr, NULL, 0);
2759 rtnl_register(PF_INET, RTM_GETADDR, NULL, inet_dump_ifaddr, 0);
2760 rtnl_register(PF_INET, RTM_GETNETCONF, inet_netconf_get_devconf,
2761 inet_netconf_dump_devconf, 0);
2762 }
2763