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 [IPV4_DEVCONF_ARP_EVICT_NOCARRIER - 1] = 1,
79 },
80 };
81
82 static struct ipv4_devconf ipv4_devconf_dflt = {
83 .data = {
84 [IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1,
85 [IPV4_DEVCONF_SEND_REDIRECTS - 1] = 1,
86 [IPV4_DEVCONF_SECURE_REDIRECTS - 1] = 1,
87 [IPV4_DEVCONF_SHARED_MEDIA - 1] = 1,
88 [IPV4_DEVCONF_ACCEPT_SOURCE_ROUTE - 1] = 1,
89 [IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL - 1] = 10000 /*ms*/,
90 [IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL - 1] = 1000 /*ms*/,
91 [IPV4_DEVCONF_ARP_EVICT_NOCARRIER - 1] = 1,
92 },
93 };
94
95 #define IPV4_DEVCONF_DFLT(net, attr) \
96 IPV4_DEVCONF((*net->ipv4.devconf_dflt), attr)
97
98 static const struct nla_policy ifa_ipv4_policy[IFA_MAX+1] = {
99 [IFA_LOCAL] = { .type = NLA_U32 },
100 [IFA_ADDRESS] = { .type = NLA_U32 },
101 [IFA_BROADCAST] = { .type = NLA_U32 },
102 [IFA_LABEL] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 },
103 [IFA_CACHEINFO] = { .len = sizeof(struct ifa_cacheinfo) },
104 [IFA_FLAGS] = { .type = NLA_U32 },
105 [IFA_RT_PRIORITY] = { .type = NLA_U32 },
106 [IFA_TARGET_NETNSID] = { .type = NLA_S32 },
107 [IFA_PROTO] = { .type = NLA_U8 },
108 };
109
110 struct inet_fill_args {
111 u32 portid;
112 u32 seq;
113 int event;
114 unsigned int flags;
115 int netnsid;
116 int ifindex;
117 };
118
119 #define IN4_ADDR_HSIZE_SHIFT 8
120 #define IN4_ADDR_HSIZE (1U << IN4_ADDR_HSIZE_SHIFT)
121
122 static struct hlist_head inet_addr_lst[IN4_ADDR_HSIZE];
123
inet_addr_hash(const struct net * net,__be32 addr)124 static u32 inet_addr_hash(const struct net *net, __be32 addr)
125 {
126 u32 val = (__force u32) addr ^ net_hash_mix(net);
127
128 return hash_32(val, IN4_ADDR_HSIZE_SHIFT);
129 }
130
inet_hash_insert(struct net * net,struct in_ifaddr * ifa)131 static void inet_hash_insert(struct net *net, struct in_ifaddr *ifa)
132 {
133 u32 hash = inet_addr_hash(net, ifa->ifa_local);
134
135 ASSERT_RTNL();
136 hlist_add_head_rcu(&ifa->hash, &inet_addr_lst[hash]);
137 }
138
inet_hash_remove(struct in_ifaddr * ifa)139 static void inet_hash_remove(struct in_ifaddr *ifa)
140 {
141 ASSERT_RTNL();
142 hlist_del_init_rcu(&ifa->hash);
143 }
144
145 /**
146 * __ip_dev_find - find the first device with a given source address.
147 * @net: the net namespace
148 * @addr: the source address
149 * @devref: if true, take a reference on the found device
150 *
151 * If a caller uses devref=false, it should be protected by RCU, or RTNL
152 */
__ip_dev_find(struct net * net,__be32 addr,bool devref)153 struct net_device *__ip_dev_find(struct net *net, __be32 addr, bool devref)
154 {
155 struct net_device *result = NULL;
156 struct in_ifaddr *ifa;
157
158 rcu_read_lock();
159 ifa = inet_lookup_ifaddr_rcu(net, addr);
160 if (!ifa) {
161 struct flowi4 fl4 = { .daddr = addr };
162 struct fib_result res = { 0 };
163 struct fib_table *local;
164
165 /* Fallback to FIB local table so that communication
166 * over loopback subnets work.
167 */
168 local = fib_get_table(net, RT_TABLE_LOCAL);
169 if (local &&
170 !fib_table_lookup(local, &fl4, &res, FIB_LOOKUP_NOREF) &&
171 res.type == RTN_LOCAL)
172 result = FIB_RES_DEV(res);
173 } else {
174 result = ifa->ifa_dev->dev;
175 }
176 if (result && devref)
177 dev_hold(result);
178 rcu_read_unlock();
179 return result;
180 }
181 EXPORT_SYMBOL(__ip_dev_find);
182
183 /* called under RCU lock */
inet_lookup_ifaddr_rcu(struct net * net,__be32 addr)184 struct in_ifaddr *inet_lookup_ifaddr_rcu(struct net *net, __be32 addr)
185 {
186 u32 hash = inet_addr_hash(net, addr);
187 struct in_ifaddr *ifa;
188
189 hlist_for_each_entry_rcu(ifa, &inet_addr_lst[hash], hash)
190 if (ifa->ifa_local == addr &&
191 net_eq(dev_net(ifa->ifa_dev->dev), net))
192 return ifa;
193
194 return NULL;
195 }
196
197 static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32);
198
199 static BLOCKING_NOTIFIER_HEAD(inetaddr_chain);
200 static BLOCKING_NOTIFIER_HEAD(inetaddr_validator_chain);
201 static void inet_del_ifa(struct in_device *in_dev,
202 struct in_ifaddr __rcu **ifap,
203 int destroy);
204 #ifdef CONFIG_SYSCTL
205 static int devinet_sysctl_register(struct in_device *idev);
206 static void devinet_sysctl_unregister(struct in_device *idev);
207 #else
devinet_sysctl_register(struct in_device * idev)208 static int devinet_sysctl_register(struct in_device *idev)
209 {
210 return 0;
211 }
devinet_sysctl_unregister(struct in_device * idev)212 static void devinet_sysctl_unregister(struct in_device *idev)
213 {
214 }
215 #endif
216
217 /* Locks all the inet devices. */
218
inet_alloc_ifa(void)219 static struct in_ifaddr *inet_alloc_ifa(void)
220 {
221 return kzalloc(sizeof(struct in_ifaddr), GFP_KERNEL_ACCOUNT);
222 }
223
inet_rcu_free_ifa(struct rcu_head * head)224 static void inet_rcu_free_ifa(struct rcu_head *head)
225 {
226 struct in_ifaddr *ifa = container_of(head, struct in_ifaddr, rcu_head);
227 if (ifa->ifa_dev)
228 in_dev_put(ifa->ifa_dev);
229 kfree(ifa);
230 }
231
inet_free_ifa(struct in_ifaddr * ifa)232 static void inet_free_ifa(struct in_ifaddr *ifa)
233 {
234 call_rcu(&ifa->rcu_head, inet_rcu_free_ifa);
235 }
236
in_dev_free_rcu(struct rcu_head * head)237 static void in_dev_free_rcu(struct rcu_head *head)
238 {
239 struct in_device *idev = container_of(head, struct in_device, rcu_head);
240
241 kfree(rcu_dereference_protected(idev->mc_hash, 1));
242 kfree(idev);
243 }
244
in_dev_finish_destroy(struct in_device * idev)245 void in_dev_finish_destroy(struct in_device *idev)
246 {
247 struct net_device *dev = idev->dev;
248
249 WARN_ON(idev->ifa_list);
250 WARN_ON(idev->mc_list);
251 #ifdef NET_REFCNT_DEBUG
252 pr_debug("%s: %p=%s\n", __func__, idev, dev ? dev->name : "NIL");
253 #endif
254 netdev_put(dev, &idev->dev_tracker);
255 if (!idev->dead)
256 pr_err("Freeing alive in_device %p\n", idev);
257 else
258 call_rcu(&idev->rcu_head, in_dev_free_rcu);
259 }
260 EXPORT_SYMBOL(in_dev_finish_destroy);
261
inetdev_init(struct net_device * dev)262 static struct in_device *inetdev_init(struct net_device *dev)
263 {
264 struct in_device *in_dev;
265 int err = -ENOMEM;
266
267 ASSERT_RTNL();
268
269 in_dev = kzalloc(sizeof(*in_dev), GFP_KERNEL);
270 if (!in_dev)
271 goto out;
272 memcpy(&in_dev->cnf, dev_net(dev)->ipv4.devconf_dflt,
273 sizeof(in_dev->cnf));
274 in_dev->cnf.sysctl = NULL;
275 in_dev->dev = dev;
276 in_dev->arp_parms = neigh_parms_alloc(dev, &arp_tbl);
277 if (!in_dev->arp_parms)
278 goto out_kfree;
279 if (IPV4_DEVCONF(in_dev->cnf, FORWARDING))
280 dev_disable_lro(dev);
281 /* Reference in_dev->dev */
282 netdev_hold(dev, &in_dev->dev_tracker, GFP_KERNEL);
283 /* Account for reference dev->ip_ptr (below) */
284 refcount_set(&in_dev->refcnt, 1);
285
286 err = devinet_sysctl_register(in_dev);
287 if (err) {
288 in_dev->dead = 1;
289 neigh_parms_release(&arp_tbl, in_dev->arp_parms);
290 in_dev_put(in_dev);
291 in_dev = NULL;
292 goto out;
293 }
294 ip_mc_init_dev(in_dev);
295 if (dev->flags & IFF_UP)
296 ip_mc_up(in_dev);
297
298 /* we can receive as soon as ip_ptr is set -- do this last */
299 rcu_assign_pointer(dev->ip_ptr, in_dev);
300 out:
301 return in_dev ?: ERR_PTR(err);
302 out_kfree:
303 kfree(in_dev);
304 in_dev = NULL;
305 goto out;
306 }
307
inetdev_destroy(struct in_device * in_dev)308 static void inetdev_destroy(struct in_device *in_dev)
309 {
310 struct net_device *dev;
311 struct in_ifaddr *ifa;
312
313 ASSERT_RTNL();
314
315 dev = in_dev->dev;
316
317 in_dev->dead = 1;
318
319 ip_mc_destroy_dev(in_dev);
320
321 while ((ifa = rtnl_dereference(in_dev->ifa_list)) != NULL) {
322 inet_del_ifa(in_dev, &in_dev->ifa_list, 0);
323 inet_free_ifa(ifa);
324 }
325
326 RCU_INIT_POINTER(dev->ip_ptr, NULL);
327
328 devinet_sysctl_unregister(in_dev);
329 neigh_parms_release(&arp_tbl, in_dev->arp_parms);
330 arp_ifdown(dev);
331
332 in_dev_put(in_dev);
333 }
334
inet_addr_onlink(struct in_device * in_dev,__be32 a,__be32 b)335 int inet_addr_onlink(struct in_device *in_dev, __be32 a, __be32 b)
336 {
337 const struct in_ifaddr *ifa;
338
339 rcu_read_lock();
340 in_dev_for_each_ifa_rcu(ifa, in_dev) {
341 if (inet_ifa_match(a, ifa)) {
342 if (!b || inet_ifa_match(b, ifa)) {
343 rcu_read_unlock();
344 return 1;
345 }
346 }
347 }
348 rcu_read_unlock();
349 return 0;
350 }
351
__inet_del_ifa(struct in_device * in_dev,struct in_ifaddr __rcu ** ifap,int destroy,struct nlmsghdr * nlh,u32 portid)352 static void __inet_del_ifa(struct in_device *in_dev,
353 struct in_ifaddr __rcu **ifap,
354 int destroy, struct nlmsghdr *nlh, u32 portid)
355 {
356 struct in_ifaddr *promote = NULL;
357 struct in_ifaddr *ifa, *ifa1;
358 struct in_ifaddr __rcu **last_prim;
359 struct in_ifaddr *prev_prom = NULL;
360 int do_promote = IN_DEV_PROMOTE_SECONDARIES(in_dev);
361
362 ASSERT_RTNL();
363
364 ifa1 = rtnl_dereference(*ifap);
365 last_prim = ifap;
366 if (in_dev->dead)
367 goto no_promotions;
368
369 /* 1. Deleting primary ifaddr forces deletion all secondaries
370 * unless alias promotion is set
371 **/
372
373 if (!(ifa1->ifa_flags & IFA_F_SECONDARY)) {
374 struct in_ifaddr __rcu **ifap1 = &ifa1->ifa_next;
375
376 while ((ifa = rtnl_dereference(*ifap1)) != NULL) {
377 if (!(ifa->ifa_flags & IFA_F_SECONDARY) &&
378 ifa1->ifa_scope <= ifa->ifa_scope)
379 last_prim = &ifa->ifa_next;
380
381 if (!(ifa->ifa_flags & IFA_F_SECONDARY) ||
382 ifa1->ifa_mask != ifa->ifa_mask ||
383 !inet_ifa_match(ifa1->ifa_address, ifa)) {
384 ifap1 = &ifa->ifa_next;
385 prev_prom = ifa;
386 continue;
387 }
388
389 if (!do_promote) {
390 inet_hash_remove(ifa);
391 *ifap1 = ifa->ifa_next;
392
393 rtmsg_ifa(RTM_DELADDR, ifa, nlh, portid);
394 blocking_notifier_call_chain(&inetaddr_chain,
395 NETDEV_DOWN, ifa);
396 inet_free_ifa(ifa);
397 } else {
398 promote = ifa;
399 break;
400 }
401 }
402 }
403
404 /* On promotion all secondaries from subnet are changing
405 * the primary IP, we must remove all their routes silently
406 * and later to add them back with new prefsrc. Do this
407 * while all addresses are on the device list.
408 */
409 for (ifa = promote; ifa; ifa = rtnl_dereference(ifa->ifa_next)) {
410 if (ifa1->ifa_mask == ifa->ifa_mask &&
411 inet_ifa_match(ifa1->ifa_address, ifa))
412 fib_del_ifaddr(ifa, ifa1);
413 }
414
415 no_promotions:
416 /* 2. Unlink it */
417
418 *ifap = ifa1->ifa_next;
419 inet_hash_remove(ifa1);
420
421 /* 3. Announce address deletion */
422
423 /* Send message first, then call notifier.
424 At first sight, FIB update triggered by notifier
425 will refer to already deleted ifaddr, that could confuse
426 netlink listeners. It is not true: look, gated sees
427 that route deleted and if it still thinks that ifaddr
428 is valid, it will try to restore deleted routes... Grr.
429 So that, this order is correct.
430 */
431 rtmsg_ifa(RTM_DELADDR, ifa1, nlh, portid);
432 blocking_notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa1);
433
434 if (promote) {
435 struct in_ifaddr *next_sec;
436
437 next_sec = rtnl_dereference(promote->ifa_next);
438 if (prev_prom) {
439 struct in_ifaddr *last_sec;
440
441 rcu_assign_pointer(prev_prom->ifa_next, next_sec);
442
443 last_sec = rtnl_dereference(*last_prim);
444 rcu_assign_pointer(promote->ifa_next, last_sec);
445 rcu_assign_pointer(*last_prim, promote);
446 }
447
448 promote->ifa_flags &= ~IFA_F_SECONDARY;
449 rtmsg_ifa(RTM_NEWADDR, promote, nlh, portid);
450 blocking_notifier_call_chain(&inetaddr_chain,
451 NETDEV_UP, promote);
452 for (ifa = next_sec; ifa;
453 ifa = rtnl_dereference(ifa->ifa_next)) {
454 if (ifa1->ifa_mask != ifa->ifa_mask ||
455 !inet_ifa_match(ifa1->ifa_address, ifa))
456 continue;
457 fib_add_ifaddr(ifa);
458 }
459
460 }
461 if (destroy)
462 inet_free_ifa(ifa1);
463 }
464
inet_del_ifa(struct in_device * in_dev,struct in_ifaddr __rcu ** ifap,int destroy)465 static void inet_del_ifa(struct in_device *in_dev,
466 struct in_ifaddr __rcu **ifap,
467 int destroy)
468 {
469 __inet_del_ifa(in_dev, ifap, destroy, NULL, 0);
470 }
471
472 static void check_lifetime(struct work_struct *work);
473
474 static DECLARE_DELAYED_WORK(check_lifetime_work, check_lifetime);
475
__inet_insert_ifa(struct in_ifaddr * ifa,struct nlmsghdr * nlh,u32 portid,struct netlink_ext_ack * extack)476 static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh,
477 u32 portid, struct netlink_ext_ack *extack)
478 {
479 struct in_ifaddr __rcu **last_primary, **ifap;
480 struct in_device *in_dev = ifa->ifa_dev;
481 struct in_validator_info ivi;
482 struct in_ifaddr *ifa1;
483 int ret;
484
485 ASSERT_RTNL();
486
487 if (!ifa->ifa_local) {
488 inet_free_ifa(ifa);
489 return 0;
490 }
491
492 ifa->ifa_flags &= ~IFA_F_SECONDARY;
493 last_primary = &in_dev->ifa_list;
494
495 /* Don't set IPv6 only flags to IPv4 addresses */
496 ifa->ifa_flags &= ~IPV6ONLY_FLAGS;
497
498 ifap = &in_dev->ifa_list;
499 ifa1 = rtnl_dereference(*ifap);
500
501 while (ifa1) {
502 if (!(ifa1->ifa_flags & IFA_F_SECONDARY) &&
503 ifa->ifa_scope <= ifa1->ifa_scope)
504 last_primary = &ifa1->ifa_next;
505 if (ifa1->ifa_mask == ifa->ifa_mask &&
506 inet_ifa_match(ifa1->ifa_address, ifa)) {
507 if (ifa1->ifa_local == ifa->ifa_local) {
508 inet_free_ifa(ifa);
509 return -EEXIST;
510 }
511 if (ifa1->ifa_scope != ifa->ifa_scope) {
512 NL_SET_ERR_MSG(extack, "ipv4: Invalid scope value");
513 inet_free_ifa(ifa);
514 return -EINVAL;
515 }
516 ifa->ifa_flags |= IFA_F_SECONDARY;
517 }
518
519 ifap = &ifa1->ifa_next;
520 ifa1 = rtnl_dereference(*ifap);
521 }
522
523 /* Allow any devices that wish to register ifaddr validtors to weigh
524 * in now, before changes are committed. The rntl lock is serializing
525 * access here, so the state should not change between a validator call
526 * and a final notify on commit. This isn't invoked on promotion under
527 * the assumption that validators are checking the address itself, and
528 * not the flags.
529 */
530 ivi.ivi_addr = ifa->ifa_address;
531 ivi.ivi_dev = ifa->ifa_dev;
532 ivi.extack = extack;
533 ret = blocking_notifier_call_chain(&inetaddr_validator_chain,
534 NETDEV_UP, &ivi);
535 ret = notifier_to_errno(ret);
536 if (ret) {
537 inet_free_ifa(ifa);
538 return ret;
539 }
540
541 if (!(ifa->ifa_flags & IFA_F_SECONDARY))
542 ifap = last_primary;
543
544 rcu_assign_pointer(ifa->ifa_next, *ifap);
545 rcu_assign_pointer(*ifap, ifa);
546
547 inet_hash_insert(dev_net(in_dev->dev), ifa);
548
549 cancel_delayed_work(&check_lifetime_work);
550 queue_delayed_work(system_power_efficient_wq, &check_lifetime_work, 0);
551
552 /* Send message first, then call notifier.
553 Notifier will trigger FIB update, so that
554 listeners of netlink will know about new ifaddr */
555 rtmsg_ifa(RTM_NEWADDR, ifa, nlh, portid);
556 blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa);
557
558 return 0;
559 }
560
inet_insert_ifa(struct in_ifaddr * ifa)561 static int inet_insert_ifa(struct in_ifaddr *ifa)
562 {
563 return __inet_insert_ifa(ifa, NULL, 0, NULL);
564 }
565
inet_set_ifa(struct net_device * dev,struct in_ifaddr * ifa)566 static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa)
567 {
568 struct in_device *in_dev = __in_dev_get_rtnl(dev);
569
570 ASSERT_RTNL();
571
572 if (!in_dev) {
573 inet_free_ifa(ifa);
574 return -ENOBUFS;
575 }
576 ipv4_devconf_setall(in_dev);
577 neigh_parms_data_state_setall(in_dev->arp_parms);
578 if (ifa->ifa_dev != in_dev) {
579 WARN_ON(ifa->ifa_dev);
580 in_dev_hold(in_dev);
581 ifa->ifa_dev = in_dev;
582 }
583 if (ipv4_is_loopback(ifa->ifa_local))
584 ifa->ifa_scope = RT_SCOPE_HOST;
585 return inet_insert_ifa(ifa);
586 }
587
588 /* Caller must hold RCU or RTNL :
589 * We dont take a reference on found in_device
590 */
inetdev_by_index(struct net * net,int ifindex)591 struct in_device *inetdev_by_index(struct net *net, int ifindex)
592 {
593 struct net_device *dev;
594 struct in_device *in_dev = NULL;
595
596 rcu_read_lock();
597 dev = dev_get_by_index_rcu(net, ifindex);
598 if (dev)
599 in_dev = rcu_dereference_rtnl(dev->ip_ptr);
600 rcu_read_unlock();
601 return in_dev;
602 }
603 EXPORT_SYMBOL(inetdev_by_index);
604
605 /* Called only from RTNL semaphored context. No locks. */
606
inet_ifa_byprefix(struct in_device * in_dev,__be32 prefix,__be32 mask)607 struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix,
608 __be32 mask)
609 {
610 struct in_ifaddr *ifa;
611
612 ASSERT_RTNL();
613
614 in_dev_for_each_ifa_rtnl(ifa, in_dev) {
615 if (ifa->ifa_mask == mask && inet_ifa_match(prefix, ifa))
616 return ifa;
617 }
618 return NULL;
619 }
620
ip_mc_autojoin_config(struct net * net,bool join,const struct in_ifaddr * ifa)621 static int ip_mc_autojoin_config(struct net *net, bool join,
622 const struct in_ifaddr *ifa)
623 {
624 #if defined(CONFIG_IP_MULTICAST)
625 struct ip_mreqn mreq = {
626 .imr_multiaddr.s_addr = ifa->ifa_address,
627 .imr_ifindex = ifa->ifa_dev->dev->ifindex,
628 };
629 struct sock *sk = net->ipv4.mc_autojoin_sk;
630 int ret;
631
632 ASSERT_RTNL();
633
634 lock_sock(sk);
635 if (join)
636 ret = ip_mc_join_group(sk, &mreq);
637 else
638 ret = ip_mc_leave_group(sk, &mreq);
639 release_sock(sk);
640
641 return ret;
642 #else
643 return -EOPNOTSUPP;
644 #endif
645 }
646
inet_rtm_deladdr(struct sk_buff * skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)647 static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
648 struct netlink_ext_ack *extack)
649 {
650 struct net *net = sock_net(skb->sk);
651 struct in_ifaddr __rcu **ifap;
652 struct nlattr *tb[IFA_MAX+1];
653 struct in_device *in_dev;
654 struct ifaddrmsg *ifm;
655 struct in_ifaddr *ifa;
656 int err;
657
658 ASSERT_RTNL();
659
660 err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
661 ifa_ipv4_policy, extack);
662 if (err < 0)
663 goto errout;
664
665 ifm = nlmsg_data(nlh);
666 in_dev = inetdev_by_index(net, ifm->ifa_index);
667 if (!in_dev) {
668 NL_SET_ERR_MSG(extack, "ipv4: Device not found");
669 err = -ENODEV;
670 goto errout;
671 }
672
673 for (ifap = &in_dev->ifa_list; (ifa = rtnl_dereference(*ifap)) != NULL;
674 ifap = &ifa->ifa_next) {
675 if (tb[IFA_LOCAL] &&
676 ifa->ifa_local != nla_get_in_addr(tb[IFA_LOCAL]))
677 continue;
678
679 if (tb[IFA_LABEL] && nla_strcmp(tb[IFA_LABEL], ifa->ifa_label))
680 continue;
681
682 if (tb[IFA_ADDRESS] &&
683 (ifm->ifa_prefixlen != ifa->ifa_prefixlen ||
684 !inet_ifa_match(nla_get_in_addr(tb[IFA_ADDRESS]), ifa)))
685 continue;
686
687 if (ipv4_is_multicast(ifa->ifa_address))
688 ip_mc_autojoin_config(net, false, ifa);
689 __inet_del_ifa(in_dev, ifap, 1, nlh, NETLINK_CB(skb).portid);
690 return 0;
691 }
692
693 NL_SET_ERR_MSG(extack, "ipv4: Address not found");
694 err = -EADDRNOTAVAIL;
695 errout:
696 return err;
697 }
698
699 #define INFINITY_LIFE_TIME 0xFFFFFFFF
700
check_lifetime(struct work_struct * work)701 static void check_lifetime(struct work_struct *work)
702 {
703 unsigned long now, next, next_sec, next_sched;
704 struct in_ifaddr *ifa;
705 struct hlist_node *n;
706 int i;
707
708 now = jiffies;
709 next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
710
711 for (i = 0; i < IN4_ADDR_HSIZE; i++) {
712 bool change_needed = false;
713
714 rcu_read_lock();
715 hlist_for_each_entry_rcu(ifa, &inet_addr_lst[i], hash) {
716 unsigned long age;
717
718 if (ifa->ifa_flags & IFA_F_PERMANENT)
719 continue;
720
721 /* We try to batch several events at once. */
722 age = (now - ifa->ifa_tstamp +
723 ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
724
725 if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME &&
726 age >= ifa->ifa_valid_lft) {
727 change_needed = true;
728 } else if (ifa->ifa_preferred_lft ==
729 INFINITY_LIFE_TIME) {
730 continue;
731 } else if (age >= ifa->ifa_preferred_lft) {
732 if (time_before(ifa->ifa_tstamp +
733 ifa->ifa_valid_lft * HZ, next))
734 next = ifa->ifa_tstamp +
735 ifa->ifa_valid_lft * HZ;
736
737 if (!(ifa->ifa_flags & IFA_F_DEPRECATED))
738 change_needed = true;
739 } else if (time_before(ifa->ifa_tstamp +
740 ifa->ifa_preferred_lft * HZ,
741 next)) {
742 next = ifa->ifa_tstamp +
743 ifa->ifa_preferred_lft * HZ;
744 }
745 }
746 rcu_read_unlock();
747 if (!change_needed)
748 continue;
749 rtnl_lock();
750 hlist_for_each_entry_safe(ifa, n, &inet_addr_lst[i], hash) {
751 unsigned long age;
752
753 if (ifa->ifa_flags & IFA_F_PERMANENT)
754 continue;
755
756 /* We try to batch several events at once. */
757 age = (now - ifa->ifa_tstamp +
758 ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
759
760 if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME &&
761 age >= ifa->ifa_valid_lft) {
762 struct in_ifaddr __rcu **ifap;
763 struct in_ifaddr *tmp;
764
765 ifap = &ifa->ifa_dev->ifa_list;
766 tmp = rtnl_dereference(*ifap);
767 while (tmp) {
768 if (tmp == ifa) {
769 inet_del_ifa(ifa->ifa_dev,
770 ifap, 1);
771 break;
772 }
773 ifap = &tmp->ifa_next;
774 tmp = rtnl_dereference(*ifap);
775 }
776 } else if (ifa->ifa_preferred_lft !=
777 INFINITY_LIFE_TIME &&
778 age >= ifa->ifa_preferred_lft &&
779 !(ifa->ifa_flags & IFA_F_DEPRECATED)) {
780 ifa->ifa_flags |= IFA_F_DEPRECATED;
781 rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0);
782 }
783 }
784 rtnl_unlock();
785 }
786
787 next_sec = round_jiffies_up(next);
788 next_sched = next;
789
790 /* If rounded timeout is accurate enough, accept it. */
791 if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
792 next_sched = next_sec;
793
794 now = jiffies;
795 /* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
796 if (time_before(next_sched, now + ADDRCONF_TIMER_FUZZ_MAX))
797 next_sched = now + ADDRCONF_TIMER_FUZZ_MAX;
798
799 queue_delayed_work(system_power_efficient_wq, &check_lifetime_work,
800 next_sched - now);
801 }
802
set_ifa_lifetime(struct in_ifaddr * ifa,__u32 valid_lft,__u32 prefered_lft)803 static void set_ifa_lifetime(struct in_ifaddr *ifa, __u32 valid_lft,
804 __u32 prefered_lft)
805 {
806 unsigned long timeout;
807
808 ifa->ifa_flags &= ~(IFA_F_PERMANENT | IFA_F_DEPRECATED);
809
810 timeout = addrconf_timeout_fixup(valid_lft, HZ);
811 if (addrconf_finite_timeout(timeout))
812 ifa->ifa_valid_lft = timeout;
813 else
814 ifa->ifa_flags |= IFA_F_PERMANENT;
815
816 timeout = addrconf_timeout_fixup(prefered_lft, HZ);
817 if (addrconf_finite_timeout(timeout)) {
818 if (timeout == 0)
819 ifa->ifa_flags |= IFA_F_DEPRECATED;
820 ifa->ifa_preferred_lft = timeout;
821 }
822 ifa->ifa_tstamp = jiffies;
823 if (!ifa->ifa_cstamp)
824 ifa->ifa_cstamp = ifa->ifa_tstamp;
825 }
826
rtm_to_ifaddr(struct net * net,struct nlmsghdr * nlh,__u32 * pvalid_lft,__u32 * pprefered_lft,struct netlink_ext_ack * extack)827 static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh,
828 __u32 *pvalid_lft, __u32 *pprefered_lft,
829 struct netlink_ext_ack *extack)
830 {
831 struct nlattr *tb[IFA_MAX+1];
832 struct in_ifaddr *ifa;
833 struct ifaddrmsg *ifm;
834 struct net_device *dev;
835 struct in_device *in_dev;
836 int err;
837
838 err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
839 ifa_ipv4_policy, extack);
840 if (err < 0)
841 goto errout;
842
843 ifm = nlmsg_data(nlh);
844 err = -EINVAL;
845
846 if (ifm->ifa_prefixlen > 32) {
847 NL_SET_ERR_MSG(extack, "ipv4: Invalid prefix length");
848 goto errout;
849 }
850
851 if (!tb[IFA_LOCAL]) {
852 NL_SET_ERR_MSG(extack, "ipv4: Local address is not supplied");
853 goto errout;
854 }
855
856 dev = __dev_get_by_index(net, ifm->ifa_index);
857 err = -ENODEV;
858 if (!dev) {
859 NL_SET_ERR_MSG(extack, "ipv4: Device not found");
860 goto errout;
861 }
862
863 in_dev = __in_dev_get_rtnl(dev);
864 err = -ENOBUFS;
865 if (!in_dev)
866 goto errout;
867
868 ifa = inet_alloc_ifa();
869 if (!ifa)
870 /*
871 * A potential indev allocation can be left alive, it stays
872 * assigned to its device and is destroy with it.
873 */
874 goto errout;
875
876 ipv4_devconf_setall(in_dev);
877 neigh_parms_data_state_setall(in_dev->arp_parms);
878 in_dev_hold(in_dev);
879
880 if (!tb[IFA_ADDRESS])
881 tb[IFA_ADDRESS] = tb[IFA_LOCAL];
882
883 INIT_HLIST_NODE(&ifa->hash);
884 ifa->ifa_prefixlen = ifm->ifa_prefixlen;
885 ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen);
886 ifa->ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) :
887 ifm->ifa_flags;
888 ifa->ifa_scope = ifm->ifa_scope;
889 ifa->ifa_dev = in_dev;
890
891 ifa->ifa_local = nla_get_in_addr(tb[IFA_LOCAL]);
892 ifa->ifa_address = nla_get_in_addr(tb[IFA_ADDRESS]);
893
894 if (tb[IFA_BROADCAST])
895 ifa->ifa_broadcast = nla_get_in_addr(tb[IFA_BROADCAST]);
896
897 if (tb[IFA_LABEL])
898 nla_strscpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ);
899 else
900 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
901
902 if (tb[IFA_RT_PRIORITY])
903 ifa->ifa_rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
904
905 if (tb[IFA_PROTO])
906 ifa->ifa_proto = nla_get_u8(tb[IFA_PROTO]);
907
908 if (tb[IFA_CACHEINFO]) {
909 struct ifa_cacheinfo *ci;
910
911 ci = nla_data(tb[IFA_CACHEINFO]);
912 if (!ci->ifa_valid || ci->ifa_prefered > ci->ifa_valid) {
913 NL_SET_ERR_MSG(extack, "ipv4: address lifetime invalid");
914 err = -EINVAL;
915 goto errout_free;
916 }
917 *pvalid_lft = ci->ifa_valid;
918 *pprefered_lft = ci->ifa_prefered;
919 }
920
921 return ifa;
922
923 errout_free:
924 inet_free_ifa(ifa);
925 errout:
926 return ERR_PTR(err);
927 }
928
find_matching_ifa(struct in_ifaddr * ifa)929 static struct in_ifaddr *find_matching_ifa(struct in_ifaddr *ifa)
930 {
931 struct in_device *in_dev = ifa->ifa_dev;
932 struct in_ifaddr *ifa1;
933
934 if (!ifa->ifa_local)
935 return NULL;
936
937 in_dev_for_each_ifa_rtnl(ifa1, in_dev) {
938 if (ifa1->ifa_mask == ifa->ifa_mask &&
939 inet_ifa_match(ifa1->ifa_address, ifa) &&
940 ifa1->ifa_local == ifa->ifa_local)
941 return ifa1;
942 }
943 return NULL;
944 }
945
inet_rtm_newaddr(struct sk_buff * skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)946 static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
947 struct netlink_ext_ack *extack)
948 {
949 struct net *net = sock_net(skb->sk);
950 struct in_ifaddr *ifa;
951 struct in_ifaddr *ifa_existing;
952 __u32 valid_lft = INFINITY_LIFE_TIME;
953 __u32 prefered_lft = INFINITY_LIFE_TIME;
954
955 ASSERT_RTNL();
956
957 ifa = rtm_to_ifaddr(net, nlh, &valid_lft, &prefered_lft, extack);
958 if (IS_ERR(ifa))
959 return PTR_ERR(ifa);
960
961 ifa_existing = find_matching_ifa(ifa);
962 if (!ifa_existing) {
963 /* It would be best to check for !NLM_F_CREATE here but
964 * userspace already relies on not having to provide this.
965 */
966 set_ifa_lifetime(ifa, valid_lft, prefered_lft);
967 if (ifa->ifa_flags & IFA_F_MCAUTOJOIN) {
968 int ret = ip_mc_autojoin_config(net, true, ifa);
969
970 if (ret < 0) {
971 NL_SET_ERR_MSG(extack, "ipv4: Multicast auto join failed");
972 inet_free_ifa(ifa);
973 return ret;
974 }
975 }
976 return __inet_insert_ifa(ifa, nlh, NETLINK_CB(skb).portid,
977 extack);
978 } else {
979 u32 new_metric = ifa->ifa_rt_priority;
980 u8 new_proto = ifa->ifa_proto;
981
982 inet_free_ifa(ifa);
983
984 if (nlh->nlmsg_flags & NLM_F_EXCL ||
985 !(nlh->nlmsg_flags & NLM_F_REPLACE)) {
986 NL_SET_ERR_MSG(extack, "ipv4: Address already assigned");
987 return -EEXIST;
988 }
989 ifa = ifa_existing;
990
991 if (ifa->ifa_rt_priority != new_metric) {
992 fib_modify_prefix_metric(ifa, new_metric);
993 ifa->ifa_rt_priority = new_metric;
994 }
995
996 ifa->ifa_proto = new_proto;
997
998 set_ifa_lifetime(ifa, valid_lft, prefered_lft);
999 cancel_delayed_work(&check_lifetime_work);
1000 queue_delayed_work(system_power_efficient_wq,
1001 &check_lifetime_work, 0);
1002 rtmsg_ifa(RTM_NEWADDR, ifa, nlh, NETLINK_CB(skb).portid);
1003 }
1004 return 0;
1005 }
1006
1007 /*
1008 * Determine a default network mask, based on the IP address.
1009 */
1010
inet_abc_len(__be32 addr)1011 static int inet_abc_len(__be32 addr)
1012 {
1013 int rc = -1; /* Something else, probably a multicast. */
1014
1015 if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr))
1016 rc = 0;
1017 else {
1018 __u32 haddr = ntohl(addr);
1019 if (IN_CLASSA(haddr))
1020 rc = 8;
1021 else if (IN_CLASSB(haddr))
1022 rc = 16;
1023 else if (IN_CLASSC(haddr))
1024 rc = 24;
1025 else if (IN_CLASSE(haddr))
1026 rc = 32;
1027 }
1028
1029 return rc;
1030 }
1031
1032
devinet_ioctl(struct net * net,unsigned int cmd,struct ifreq * ifr)1033 int devinet_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr)
1034 {
1035 struct sockaddr_in sin_orig;
1036 struct sockaddr_in *sin = (struct sockaddr_in *)&ifr->ifr_addr;
1037 struct in_ifaddr __rcu **ifap = NULL;
1038 struct in_device *in_dev;
1039 struct in_ifaddr *ifa = NULL;
1040 struct net_device *dev;
1041 char *colon;
1042 int ret = -EFAULT;
1043 int tryaddrmatch = 0;
1044
1045 ifr->ifr_name[IFNAMSIZ - 1] = 0;
1046
1047 /* save original address for comparison */
1048 memcpy(&sin_orig, sin, sizeof(*sin));
1049
1050 colon = strchr(ifr->ifr_name, ':');
1051 if (colon)
1052 *colon = 0;
1053
1054 dev_load(net, ifr->ifr_name);
1055
1056 switch (cmd) {
1057 case SIOCGIFADDR: /* Get interface address */
1058 case SIOCGIFBRDADDR: /* Get the broadcast address */
1059 case SIOCGIFDSTADDR: /* Get the destination address */
1060 case SIOCGIFNETMASK: /* Get the netmask for the interface */
1061 /* Note that these ioctls will not sleep,
1062 so that we do not impose a lock.
1063 One day we will be forced to put shlock here (I mean SMP)
1064 */
1065 tryaddrmatch = (sin_orig.sin_family == AF_INET);
1066 memset(sin, 0, sizeof(*sin));
1067 sin->sin_family = AF_INET;
1068 break;
1069
1070 case SIOCSIFFLAGS:
1071 ret = -EPERM;
1072 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1073 goto out;
1074 break;
1075 case SIOCSIFADDR: /* Set interface address (and family) */
1076 case SIOCSIFBRDADDR: /* Set the broadcast address */
1077 case SIOCSIFDSTADDR: /* Set the destination address */
1078 case SIOCSIFNETMASK: /* Set the netmask for the interface */
1079 ret = -EPERM;
1080 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1081 goto out;
1082 ret = -EINVAL;
1083 if (sin->sin_family != AF_INET)
1084 goto out;
1085 break;
1086 default:
1087 ret = -EINVAL;
1088 goto out;
1089 }
1090
1091 rtnl_lock();
1092
1093 ret = -ENODEV;
1094 dev = __dev_get_by_name(net, ifr->ifr_name);
1095 if (!dev)
1096 goto done;
1097
1098 if (colon)
1099 *colon = ':';
1100
1101 in_dev = __in_dev_get_rtnl(dev);
1102 if (in_dev) {
1103 if (tryaddrmatch) {
1104 /* Matthias Andree */
1105 /* compare label and address (4.4BSD style) */
1106 /* note: we only do this for a limited set of ioctls
1107 and only if the original address family was AF_INET.
1108 This is checked above. */
1109
1110 for (ifap = &in_dev->ifa_list;
1111 (ifa = rtnl_dereference(*ifap)) != NULL;
1112 ifap = &ifa->ifa_next) {
1113 if (!strcmp(ifr->ifr_name, ifa->ifa_label) &&
1114 sin_orig.sin_addr.s_addr ==
1115 ifa->ifa_local) {
1116 break; /* found */
1117 }
1118 }
1119 }
1120 /* we didn't get a match, maybe the application is
1121 4.3BSD-style and passed in junk so we fall back to
1122 comparing just the label */
1123 if (!ifa) {
1124 for (ifap = &in_dev->ifa_list;
1125 (ifa = rtnl_dereference(*ifap)) != NULL;
1126 ifap = &ifa->ifa_next)
1127 if (!strcmp(ifr->ifr_name, ifa->ifa_label))
1128 break;
1129 }
1130 }
1131
1132 ret = -EADDRNOTAVAIL;
1133 if (!ifa && cmd != SIOCSIFADDR && cmd != SIOCSIFFLAGS)
1134 goto done;
1135
1136 switch (cmd) {
1137 case SIOCGIFADDR: /* Get interface address */
1138 ret = 0;
1139 sin->sin_addr.s_addr = ifa->ifa_local;
1140 break;
1141
1142 case SIOCGIFBRDADDR: /* Get the broadcast address */
1143 ret = 0;
1144 sin->sin_addr.s_addr = ifa->ifa_broadcast;
1145 break;
1146
1147 case SIOCGIFDSTADDR: /* Get the destination address */
1148 ret = 0;
1149 sin->sin_addr.s_addr = ifa->ifa_address;
1150 break;
1151
1152 case SIOCGIFNETMASK: /* Get the netmask for the interface */
1153 ret = 0;
1154 sin->sin_addr.s_addr = ifa->ifa_mask;
1155 break;
1156
1157 case SIOCSIFFLAGS:
1158 if (colon) {
1159 ret = -EADDRNOTAVAIL;
1160 if (!ifa)
1161 break;
1162 ret = 0;
1163 if (!(ifr->ifr_flags & IFF_UP))
1164 inet_del_ifa(in_dev, ifap, 1);
1165 break;
1166 }
1167 ret = dev_change_flags(dev, ifr->ifr_flags, NULL);
1168 break;
1169
1170 case SIOCSIFADDR: /* Set interface address (and family) */
1171 ret = -EINVAL;
1172 if (inet_abc_len(sin->sin_addr.s_addr) < 0)
1173 break;
1174
1175 if (!ifa) {
1176 ret = -ENOBUFS;
1177 ifa = inet_alloc_ifa();
1178 if (!ifa)
1179 break;
1180 INIT_HLIST_NODE(&ifa->hash);
1181 if (colon)
1182 memcpy(ifa->ifa_label, ifr->ifr_name, IFNAMSIZ);
1183 else
1184 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1185 } else {
1186 ret = 0;
1187 if (ifa->ifa_local == sin->sin_addr.s_addr)
1188 break;
1189 inet_del_ifa(in_dev, ifap, 0);
1190 ifa->ifa_broadcast = 0;
1191 ifa->ifa_scope = 0;
1192 }
1193
1194 ifa->ifa_address = ifa->ifa_local = sin->sin_addr.s_addr;
1195
1196 if (!(dev->flags & IFF_POINTOPOINT)) {
1197 ifa->ifa_prefixlen = inet_abc_len(ifa->ifa_address);
1198 ifa->ifa_mask = inet_make_mask(ifa->ifa_prefixlen);
1199 if ((dev->flags & IFF_BROADCAST) &&
1200 ifa->ifa_prefixlen < 31)
1201 ifa->ifa_broadcast = ifa->ifa_address |
1202 ~ifa->ifa_mask;
1203 } else {
1204 ifa->ifa_prefixlen = 32;
1205 ifa->ifa_mask = inet_make_mask(32);
1206 }
1207 set_ifa_lifetime(ifa, INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
1208 ret = inet_set_ifa(dev, ifa);
1209 break;
1210
1211 case SIOCSIFBRDADDR: /* Set the broadcast address */
1212 ret = 0;
1213 if (ifa->ifa_broadcast != sin->sin_addr.s_addr) {
1214 inet_del_ifa(in_dev, ifap, 0);
1215 ifa->ifa_broadcast = sin->sin_addr.s_addr;
1216 inet_insert_ifa(ifa);
1217 }
1218 break;
1219
1220 case SIOCSIFDSTADDR: /* Set the destination address */
1221 ret = 0;
1222 if (ifa->ifa_address == sin->sin_addr.s_addr)
1223 break;
1224 ret = -EINVAL;
1225 if (inet_abc_len(sin->sin_addr.s_addr) < 0)
1226 break;
1227 ret = 0;
1228 inet_del_ifa(in_dev, ifap, 0);
1229 ifa->ifa_address = sin->sin_addr.s_addr;
1230 inet_insert_ifa(ifa);
1231 break;
1232
1233 case SIOCSIFNETMASK: /* Set the netmask for the interface */
1234
1235 /*
1236 * The mask we set must be legal.
1237 */
1238 ret = -EINVAL;
1239 if (bad_mask(sin->sin_addr.s_addr, 0))
1240 break;
1241 ret = 0;
1242 if (ifa->ifa_mask != sin->sin_addr.s_addr) {
1243 __be32 old_mask = ifa->ifa_mask;
1244 inet_del_ifa(in_dev, ifap, 0);
1245 ifa->ifa_mask = sin->sin_addr.s_addr;
1246 ifa->ifa_prefixlen = inet_mask_len(ifa->ifa_mask);
1247
1248 /* See if current broadcast address matches
1249 * with current netmask, then recalculate
1250 * the broadcast address. Otherwise it's a
1251 * funny address, so don't touch it since
1252 * the user seems to know what (s)he's doing...
1253 */
1254 if ((dev->flags & IFF_BROADCAST) &&
1255 (ifa->ifa_prefixlen < 31) &&
1256 (ifa->ifa_broadcast ==
1257 (ifa->ifa_local|~old_mask))) {
1258 ifa->ifa_broadcast = (ifa->ifa_local |
1259 ~sin->sin_addr.s_addr);
1260 }
1261 inet_insert_ifa(ifa);
1262 }
1263 break;
1264 }
1265 done:
1266 rtnl_unlock();
1267 out:
1268 return ret;
1269 }
1270
inet_gifconf(struct net_device * dev,char __user * buf,int len,int size)1271 int inet_gifconf(struct net_device *dev, char __user *buf, int len, int size)
1272 {
1273 struct in_device *in_dev = __in_dev_get_rtnl(dev);
1274 const struct in_ifaddr *ifa;
1275 struct ifreq ifr;
1276 int done = 0;
1277
1278 if (WARN_ON(size > sizeof(struct ifreq)))
1279 goto out;
1280
1281 if (!in_dev)
1282 goto out;
1283
1284 in_dev_for_each_ifa_rtnl(ifa, in_dev) {
1285 if (!buf) {
1286 done += size;
1287 continue;
1288 }
1289 if (len < size)
1290 break;
1291 memset(&ifr, 0, sizeof(struct ifreq));
1292 strcpy(ifr.ifr_name, ifa->ifa_label);
1293
1294 (*(struct sockaddr_in *)&ifr.ifr_addr).sin_family = AF_INET;
1295 (*(struct sockaddr_in *)&ifr.ifr_addr).sin_addr.s_addr =
1296 ifa->ifa_local;
1297
1298 if (copy_to_user(buf + done, &ifr, size)) {
1299 done = -EFAULT;
1300 break;
1301 }
1302 len -= size;
1303 done += size;
1304 }
1305 out:
1306 return done;
1307 }
1308
in_dev_select_addr(const struct in_device * in_dev,int scope)1309 static __be32 in_dev_select_addr(const struct in_device *in_dev,
1310 int scope)
1311 {
1312 const struct in_ifaddr *ifa;
1313
1314 in_dev_for_each_ifa_rcu(ifa, in_dev) {
1315 if (ifa->ifa_flags & IFA_F_SECONDARY)
1316 continue;
1317 if (ifa->ifa_scope != RT_SCOPE_LINK &&
1318 ifa->ifa_scope <= scope)
1319 return ifa->ifa_local;
1320 }
1321
1322 return 0;
1323 }
1324
inet_select_addr(const struct net_device * dev,__be32 dst,int scope)1325 __be32 inet_select_addr(const struct net_device *dev, __be32 dst, int scope)
1326 {
1327 const struct in_ifaddr *ifa;
1328 __be32 addr = 0;
1329 unsigned char localnet_scope = RT_SCOPE_HOST;
1330 struct in_device *in_dev;
1331 struct net *net = dev_net(dev);
1332 int master_idx;
1333
1334 rcu_read_lock();
1335 in_dev = __in_dev_get_rcu(dev);
1336 if (!in_dev)
1337 goto no_in_dev;
1338
1339 if (unlikely(IN_DEV_ROUTE_LOCALNET(in_dev)))
1340 localnet_scope = RT_SCOPE_LINK;
1341
1342 in_dev_for_each_ifa_rcu(ifa, in_dev) {
1343 if (ifa->ifa_flags & IFA_F_SECONDARY)
1344 continue;
1345 if (min(ifa->ifa_scope, localnet_scope) > scope)
1346 continue;
1347 if (!dst || inet_ifa_match(dst, ifa)) {
1348 addr = ifa->ifa_local;
1349 break;
1350 }
1351 if (!addr)
1352 addr = ifa->ifa_local;
1353 }
1354
1355 if (addr)
1356 goto out_unlock;
1357 no_in_dev:
1358 master_idx = l3mdev_master_ifindex_rcu(dev);
1359
1360 /* For VRFs, the VRF device takes the place of the loopback device,
1361 * with addresses on it being preferred. Note in such cases the
1362 * loopback device will be among the devices that fail the master_idx
1363 * equality check in the loop below.
1364 */
1365 if (master_idx &&
1366 (dev = dev_get_by_index_rcu(net, master_idx)) &&
1367 (in_dev = __in_dev_get_rcu(dev))) {
1368 addr = in_dev_select_addr(in_dev, scope);
1369 if (addr)
1370 goto out_unlock;
1371 }
1372
1373 /* Not loopback addresses on loopback should be preferred
1374 in this case. It is important that lo is the first interface
1375 in dev_base list.
1376 */
1377 for_each_netdev_rcu(net, dev) {
1378 if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1379 continue;
1380
1381 in_dev = __in_dev_get_rcu(dev);
1382 if (!in_dev)
1383 continue;
1384
1385 addr = in_dev_select_addr(in_dev, scope);
1386 if (addr)
1387 goto out_unlock;
1388 }
1389 out_unlock:
1390 rcu_read_unlock();
1391 return addr;
1392 }
1393 EXPORT_SYMBOL(inet_select_addr);
1394
confirm_addr_indev(struct in_device * in_dev,__be32 dst,__be32 local,int scope)1395 static __be32 confirm_addr_indev(struct in_device *in_dev, __be32 dst,
1396 __be32 local, int scope)
1397 {
1398 unsigned char localnet_scope = RT_SCOPE_HOST;
1399 const struct in_ifaddr *ifa;
1400 __be32 addr = 0;
1401 int same = 0;
1402
1403 if (unlikely(IN_DEV_ROUTE_LOCALNET(in_dev)))
1404 localnet_scope = RT_SCOPE_LINK;
1405
1406 in_dev_for_each_ifa_rcu(ifa, in_dev) {
1407 unsigned char min_scope = min(ifa->ifa_scope, localnet_scope);
1408
1409 if (!addr &&
1410 (local == ifa->ifa_local || !local) &&
1411 min_scope <= scope) {
1412 addr = ifa->ifa_local;
1413 if (same)
1414 break;
1415 }
1416 if (!same) {
1417 same = (!local || inet_ifa_match(local, ifa)) &&
1418 (!dst || inet_ifa_match(dst, ifa));
1419 if (same && addr) {
1420 if (local || !dst)
1421 break;
1422 /* Is the selected addr into dst subnet? */
1423 if (inet_ifa_match(addr, ifa))
1424 break;
1425 /* No, then can we use new local src? */
1426 if (min_scope <= scope) {
1427 addr = ifa->ifa_local;
1428 break;
1429 }
1430 /* search for large dst subnet for addr */
1431 same = 0;
1432 }
1433 }
1434 }
1435
1436 return same ? addr : 0;
1437 }
1438
1439 /*
1440 * Confirm that local IP address exists using wildcards:
1441 * - net: netns to check, cannot be NULL
1442 * - in_dev: only on this interface, NULL=any interface
1443 * - dst: only in the same subnet as dst, 0=any dst
1444 * - local: address, 0=autoselect the local address
1445 * - scope: maximum allowed scope value for the local address
1446 */
inet_confirm_addr(struct net * net,struct in_device * in_dev,__be32 dst,__be32 local,int scope)1447 __be32 inet_confirm_addr(struct net *net, struct in_device *in_dev,
1448 __be32 dst, __be32 local, int scope)
1449 {
1450 __be32 addr = 0;
1451 struct net_device *dev;
1452
1453 if (in_dev)
1454 return confirm_addr_indev(in_dev, dst, local, scope);
1455
1456 rcu_read_lock();
1457 for_each_netdev_rcu(net, dev) {
1458 in_dev = __in_dev_get_rcu(dev);
1459 if (in_dev) {
1460 addr = confirm_addr_indev(in_dev, dst, local, scope);
1461 if (addr)
1462 break;
1463 }
1464 }
1465 rcu_read_unlock();
1466
1467 return addr;
1468 }
1469 EXPORT_SYMBOL(inet_confirm_addr);
1470
1471 /*
1472 * Device notifier
1473 */
1474
register_inetaddr_notifier(struct notifier_block * nb)1475 int register_inetaddr_notifier(struct notifier_block *nb)
1476 {
1477 return blocking_notifier_chain_register(&inetaddr_chain, nb);
1478 }
1479 EXPORT_SYMBOL(register_inetaddr_notifier);
1480
unregister_inetaddr_notifier(struct notifier_block * nb)1481 int unregister_inetaddr_notifier(struct notifier_block *nb)
1482 {
1483 return blocking_notifier_chain_unregister(&inetaddr_chain, nb);
1484 }
1485 EXPORT_SYMBOL(unregister_inetaddr_notifier);
1486
register_inetaddr_validator_notifier(struct notifier_block * nb)1487 int register_inetaddr_validator_notifier(struct notifier_block *nb)
1488 {
1489 return blocking_notifier_chain_register(&inetaddr_validator_chain, nb);
1490 }
1491 EXPORT_SYMBOL(register_inetaddr_validator_notifier);
1492
unregister_inetaddr_validator_notifier(struct notifier_block * nb)1493 int unregister_inetaddr_validator_notifier(struct notifier_block *nb)
1494 {
1495 return blocking_notifier_chain_unregister(&inetaddr_validator_chain,
1496 nb);
1497 }
1498 EXPORT_SYMBOL(unregister_inetaddr_validator_notifier);
1499
1500 /* Rename ifa_labels for a device name change. Make some effort to preserve
1501 * existing alias numbering and to create unique labels if possible.
1502 */
inetdev_changename(struct net_device * dev,struct in_device * in_dev)1503 static void inetdev_changename(struct net_device *dev, struct in_device *in_dev)
1504 {
1505 struct in_ifaddr *ifa;
1506 int named = 0;
1507
1508 in_dev_for_each_ifa_rtnl(ifa, in_dev) {
1509 char old[IFNAMSIZ], *dot;
1510
1511 memcpy(old, ifa->ifa_label, IFNAMSIZ);
1512 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1513 if (named++ == 0)
1514 goto skip;
1515 dot = strchr(old, ':');
1516 if (!dot) {
1517 sprintf(old, ":%d", named);
1518 dot = old;
1519 }
1520 if (strlen(dot) + strlen(dev->name) < IFNAMSIZ)
1521 strcat(ifa->ifa_label, dot);
1522 else
1523 strcpy(ifa->ifa_label + (IFNAMSIZ - strlen(dot) - 1), dot);
1524 skip:
1525 rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0);
1526 }
1527 }
1528
inetdev_send_gratuitous_arp(struct net_device * dev,struct in_device * in_dev)1529 static void inetdev_send_gratuitous_arp(struct net_device *dev,
1530 struct in_device *in_dev)
1531
1532 {
1533 const struct in_ifaddr *ifa;
1534
1535 in_dev_for_each_ifa_rtnl(ifa, in_dev) {
1536 arp_send(ARPOP_REQUEST, ETH_P_ARP,
1537 ifa->ifa_local, dev,
1538 ifa->ifa_local, NULL,
1539 dev->dev_addr, NULL);
1540 }
1541 }
1542
1543 /* Called only under RTNL semaphore */
1544
inetdev_event(struct notifier_block * this,unsigned long event,void * ptr)1545 static int inetdev_event(struct notifier_block *this, unsigned long event,
1546 void *ptr)
1547 {
1548 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1549 struct in_device *in_dev = __in_dev_get_rtnl(dev);
1550
1551 ASSERT_RTNL();
1552
1553 if (!in_dev) {
1554 if (event == NETDEV_REGISTER) {
1555 in_dev = inetdev_init(dev);
1556 if (IS_ERR(in_dev))
1557 return notifier_from_errno(PTR_ERR(in_dev));
1558 if (dev->flags & IFF_LOOPBACK) {
1559 IN_DEV_CONF_SET(in_dev, NOXFRM, 1);
1560 IN_DEV_CONF_SET(in_dev, NOPOLICY, 1);
1561 }
1562 } else if (event == NETDEV_CHANGEMTU) {
1563 /* Re-enabling IP */
1564 if (inetdev_valid_mtu(dev->mtu))
1565 in_dev = inetdev_init(dev);
1566 }
1567 goto out;
1568 }
1569
1570 switch (event) {
1571 case NETDEV_REGISTER:
1572 pr_debug("%s: bug\n", __func__);
1573 RCU_INIT_POINTER(dev->ip_ptr, NULL);
1574 break;
1575 case NETDEV_UP:
1576 if (!inetdev_valid_mtu(dev->mtu))
1577 break;
1578 if (dev->flags & IFF_LOOPBACK) {
1579 struct in_ifaddr *ifa = inet_alloc_ifa();
1580
1581 if (ifa) {
1582 INIT_HLIST_NODE(&ifa->hash);
1583 ifa->ifa_local =
1584 ifa->ifa_address = htonl(INADDR_LOOPBACK);
1585 ifa->ifa_prefixlen = 8;
1586 ifa->ifa_mask = inet_make_mask(8);
1587 in_dev_hold(in_dev);
1588 ifa->ifa_dev = in_dev;
1589 ifa->ifa_scope = RT_SCOPE_HOST;
1590 memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
1591 set_ifa_lifetime(ifa, INFINITY_LIFE_TIME,
1592 INFINITY_LIFE_TIME);
1593 ipv4_devconf_setall(in_dev);
1594 neigh_parms_data_state_setall(in_dev->arp_parms);
1595 inet_insert_ifa(ifa);
1596 }
1597 }
1598 ip_mc_up(in_dev);
1599 fallthrough;
1600 case NETDEV_CHANGEADDR:
1601 if (!IN_DEV_ARP_NOTIFY(in_dev))
1602 break;
1603 fallthrough;
1604 case NETDEV_NOTIFY_PEERS:
1605 /* Send gratuitous ARP to notify of link change */
1606 inetdev_send_gratuitous_arp(dev, in_dev);
1607 break;
1608 case NETDEV_DOWN:
1609 ip_mc_down(in_dev);
1610 break;
1611 case NETDEV_PRE_TYPE_CHANGE:
1612 ip_mc_unmap(in_dev);
1613 break;
1614 case NETDEV_POST_TYPE_CHANGE:
1615 ip_mc_remap(in_dev);
1616 break;
1617 case NETDEV_CHANGEMTU:
1618 if (inetdev_valid_mtu(dev->mtu))
1619 break;
1620 /* disable IP when MTU is not enough */
1621 fallthrough;
1622 case NETDEV_UNREGISTER:
1623 inetdev_destroy(in_dev);
1624 break;
1625 case NETDEV_CHANGENAME:
1626 /* Do not notify about label change, this event is
1627 * not interesting to applications using netlink.
1628 */
1629 inetdev_changename(dev, in_dev);
1630
1631 devinet_sysctl_unregister(in_dev);
1632 devinet_sysctl_register(in_dev);
1633 break;
1634 }
1635 out:
1636 return NOTIFY_DONE;
1637 }
1638
1639 static struct notifier_block ip_netdev_notifier = {
1640 .notifier_call = inetdev_event,
1641 };
1642
inet_nlmsg_size(void)1643 static size_t inet_nlmsg_size(void)
1644 {
1645 return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
1646 + nla_total_size(4) /* IFA_ADDRESS */
1647 + nla_total_size(4) /* IFA_LOCAL */
1648 + nla_total_size(4) /* IFA_BROADCAST */
1649 + nla_total_size(IFNAMSIZ) /* IFA_LABEL */
1650 + nla_total_size(4) /* IFA_FLAGS */
1651 + nla_total_size(1) /* IFA_PROTO */
1652 + nla_total_size(4) /* IFA_RT_PRIORITY */
1653 + nla_total_size(sizeof(struct ifa_cacheinfo)); /* IFA_CACHEINFO */
1654 }
1655
cstamp_delta(unsigned long cstamp)1656 static inline u32 cstamp_delta(unsigned long cstamp)
1657 {
1658 return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
1659 }
1660
put_cacheinfo(struct sk_buff * skb,unsigned long cstamp,unsigned long tstamp,u32 preferred,u32 valid)1661 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
1662 unsigned long tstamp, u32 preferred, u32 valid)
1663 {
1664 struct ifa_cacheinfo ci;
1665
1666 ci.cstamp = cstamp_delta(cstamp);
1667 ci.tstamp = cstamp_delta(tstamp);
1668 ci.ifa_prefered = preferred;
1669 ci.ifa_valid = valid;
1670
1671 return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
1672 }
1673
inet_fill_ifaddr(struct sk_buff * skb,struct in_ifaddr * ifa,struct inet_fill_args * args)1674 static int inet_fill_ifaddr(struct sk_buff *skb, struct in_ifaddr *ifa,
1675 struct inet_fill_args *args)
1676 {
1677 struct ifaddrmsg *ifm;
1678 struct nlmsghdr *nlh;
1679 u32 preferred, valid;
1680
1681 nlh = nlmsg_put(skb, args->portid, args->seq, args->event, sizeof(*ifm),
1682 args->flags);
1683 if (!nlh)
1684 return -EMSGSIZE;
1685
1686 ifm = nlmsg_data(nlh);
1687 ifm->ifa_family = AF_INET;
1688 ifm->ifa_prefixlen = ifa->ifa_prefixlen;
1689 ifm->ifa_flags = ifa->ifa_flags;
1690 ifm->ifa_scope = ifa->ifa_scope;
1691 ifm->ifa_index = ifa->ifa_dev->dev->ifindex;
1692
1693 if (args->netnsid >= 0 &&
1694 nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
1695 goto nla_put_failure;
1696
1697 if (!(ifm->ifa_flags & IFA_F_PERMANENT)) {
1698 preferred = ifa->ifa_preferred_lft;
1699 valid = ifa->ifa_valid_lft;
1700 if (preferred != INFINITY_LIFE_TIME) {
1701 long tval = (jiffies - ifa->ifa_tstamp) / HZ;
1702
1703 if (preferred > tval)
1704 preferred -= tval;
1705 else
1706 preferred = 0;
1707 if (valid != INFINITY_LIFE_TIME) {
1708 if (valid > tval)
1709 valid -= tval;
1710 else
1711 valid = 0;
1712 }
1713 }
1714 } else {
1715 preferred = INFINITY_LIFE_TIME;
1716 valid = INFINITY_LIFE_TIME;
1717 }
1718 if ((ifa->ifa_address &&
1719 nla_put_in_addr(skb, IFA_ADDRESS, ifa->ifa_address)) ||
1720 (ifa->ifa_local &&
1721 nla_put_in_addr(skb, IFA_LOCAL, ifa->ifa_local)) ||
1722 (ifa->ifa_broadcast &&
1723 nla_put_in_addr(skb, IFA_BROADCAST, ifa->ifa_broadcast)) ||
1724 (ifa->ifa_label[0] &&
1725 nla_put_string(skb, IFA_LABEL, ifa->ifa_label)) ||
1726 (ifa->ifa_proto &&
1727 nla_put_u8(skb, IFA_PROTO, ifa->ifa_proto)) ||
1728 nla_put_u32(skb, IFA_FLAGS, ifa->ifa_flags) ||
1729 (ifa->ifa_rt_priority &&
1730 nla_put_u32(skb, IFA_RT_PRIORITY, ifa->ifa_rt_priority)) ||
1731 put_cacheinfo(skb, ifa->ifa_cstamp, ifa->ifa_tstamp,
1732 preferred, valid))
1733 goto nla_put_failure;
1734
1735 nlmsg_end(skb, nlh);
1736 return 0;
1737
1738 nla_put_failure:
1739 nlmsg_cancel(skb, nlh);
1740 return -EMSGSIZE;
1741 }
1742
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)1743 static int inet_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
1744 struct inet_fill_args *fillargs,
1745 struct net **tgt_net, struct sock *sk,
1746 struct netlink_callback *cb)
1747 {
1748 struct netlink_ext_ack *extack = cb->extack;
1749 struct nlattr *tb[IFA_MAX+1];
1750 struct ifaddrmsg *ifm;
1751 int err, i;
1752
1753 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
1754 NL_SET_ERR_MSG(extack, "ipv4: Invalid header for address dump request");
1755 return -EINVAL;
1756 }
1757
1758 ifm = nlmsg_data(nlh);
1759 if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
1760 NL_SET_ERR_MSG(extack, "ipv4: Invalid values in header for address dump request");
1761 return -EINVAL;
1762 }
1763
1764 fillargs->ifindex = ifm->ifa_index;
1765 if (fillargs->ifindex) {
1766 cb->answer_flags |= NLM_F_DUMP_FILTERED;
1767 fillargs->flags |= NLM_F_DUMP_FILTERED;
1768 }
1769
1770 err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
1771 ifa_ipv4_policy, extack);
1772 if (err < 0)
1773 return err;
1774
1775 for (i = 0; i <= IFA_MAX; ++i) {
1776 if (!tb[i])
1777 continue;
1778
1779 if (i == IFA_TARGET_NETNSID) {
1780 struct net *net;
1781
1782 fillargs->netnsid = nla_get_s32(tb[i]);
1783
1784 net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
1785 if (IS_ERR(net)) {
1786 fillargs->netnsid = -1;
1787 NL_SET_ERR_MSG(extack, "ipv4: Invalid target network namespace id");
1788 return PTR_ERR(net);
1789 }
1790 *tgt_net = net;
1791 } else {
1792 NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in dump request");
1793 return -EINVAL;
1794 }
1795 }
1796
1797 return 0;
1798 }
1799
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)1800 static int in_dev_dump_addr(struct in_device *in_dev, struct sk_buff *skb,
1801 struct netlink_callback *cb, int s_ip_idx,
1802 struct inet_fill_args *fillargs)
1803 {
1804 struct in_ifaddr *ifa;
1805 int ip_idx = 0;
1806 int err;
1807
1808 in_dev_for_each_ifa_rtnl(ifa, in_dev) {
1809 if (ip_idx < s_ip_idx) {
1810 ip_idx++;
1811 continue;
1812 }
1813 err = inet_fill_ifaddr(skb, ifa, fillargs);
1814 if (err < 0)
1815 goto done;
1816
1817 nl_dump_check_consistent(cb, nlmsg_hdr(skb));
1818 ip_idx++;
1819 }
1820 err = 0;
1821
1822 done:
1823 cb->args[2] = ip_idx;
1824
1825 return err;
1826 }
1827
1828 /* Combine dev_addr_genid and dev_base_seq to detect changes.
1829 */
inet_base_seq(const struct net * net)1830 static u32 inet_base_seq(const struct net *net)
1831 {
1832 u32 res = atomic_read(&net->ipv4.dev_addr_genid) +
1833 net->dev_base_seq;
1834
1835 /* Must not return 0 (see nl_dump_check_consistent()).
1836 * Chose a value far away from 0.
1837 */
1838 if (!res)
1839 res = 0x80000000;
1840 return res;
1841 }
1842
inet_dump_ifaddr(struct sk_buff * skb,struct netlink_callback * cb)1843 static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
1844 {
1845 const struct nlmsghdr *nlh = cb->nlh;
1846 struct inet_fill_args fillargs = {
1847 .portid = NETLINK_CB(cb->skb).portid,
1848 .seq = nlh->nlmsg_seq,
1849 .event = RTM_NEWADDR,
1850 .flags = NLM_F_MULTI,
1851 .netnsid = -1,
1852 };
1853 struct net *net = sock_net(skb->sk);
1854 struct net *tgt_net = net;
1855 int h, s_h;
1856 int idx, s_idx;
1857 int s_ip_idx;
1858 struct net_device *dev;
1859 struct in_device *in_dev;
1860 struct hlist_head *head;
1861 int err = 0;
1862
1863 s_h = cb->args[0];
1864 s_idx = idx = cb->args[1];
1865 s_ip_idx = cb->args[2];
1866
1867 if (cb->strict_check) {
1868 err = inet_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
1869 skb->sk, cb);
1870 if (err < 0)
1871 goto put_tgt_net;
1872
1873 err = 0;
1874 if (fillargs.ifindex) {
1875 dev = __dev_get_by_index(tgt_net, fillargs.ifindex);
1876 if (!dev) {
1877 err = -ENODEV;
1878 goto put_tgt_net;
1879 }
1880
1881 in_dev = __in_dev_get_rtnl(dev);
1882 if (in_dev) {
1883 err = in_dev_dump_addr(in_dev, skb, cb, s_ip_idx,
1884 &fillargs);
1885 }
1886 goto put_tgt_net;
1887 }
1888 }
1889
1890 for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
1891 idx = 0;
1892 head = &tgt_net->dev_index_head[h];
1893 rcu_read_lock();
1894 cb->seq = inet_base_seq(tgt_net);
1895 hlist_for_each_entry_rcu(dev, head, index_hlist) {
1896 if (idx < s_idx)
1897 goto cont;
1898 if (h > s_h || idx > s_idx)
1899 s_ip_idx = 0;
1900 in_dev = __in_dev_get_rcu(dev);
1901 if (!in_dev)
1902 goto cont;
1903
1904 err = in_dev_dump_addr(in_dev, skb, cb, s_ip_idx,
1905 &fillargs);
1906 if (err < 0) {
1907 rcu_read_unlock();
1908 goto done;
1909 }
1910 cont:
1911 idx++;
1912 }
1913 rcu_read_unlock();
1914 }
1915
1916 done:
1917 cb->args[0] = h;
1918 cb->args[1] = idx;
1919 put_tgt_net:
1920 if (fillargs.netnsid >= 0)
1921 put_net(tgt_net);
1922
1923 return skb->len ? : err;
1924 }
1925
rtmsg_ifa(int event,struct in_ifaddr * ifa,struct nlmsghdr * nlh,u32 portid)1926 static void rtmsg_ifa(int event, struct in_ifaddr *ifa, struct nlmsghdr *nlh,
1927 u32 portid)
1928 {
1929 struct inet_fill_args fillargs = {
1930 .portid = portid,
1931 .seq = nlh ? nlh->nlmsg_seq : 0,
1932 .event = event,
1933 .flags = 0,
1934 .netnsid = -1,
1935 };
1936 struct sk_buff *skb;
1937 int err = -ENOBUFS;
1938 struct net *net;
1939
1940 net = dev_net(ifa->ifa_dev->dev);
1941 skb = nlmsg_new(inet_nlmsg_size(), GFP_KERNEL);
1942 if (!skb)
1943 goto errout;
1944
1945 err = inet_fill_ifaddr(skb, ifa, &fillargs);
1946 if (err < 0) {
1947 /* -EMSGSIZE implies BUG in inet_nlmsg_size() */
1948 WARN_ON(err == -EMSGSIZE);
1949 kfree_skb(skb);
1950 goto errout;
1951 }
1952 rtnl_notify(skb, net, portid, RTNLGRP_IPV4_IFADDR, nlh, GFP_KERNEL);
1953 return;
1954 errout:
1955 if (err < 0)
1956 rtnl_set_sk_err(net, RTNLGRP_IPV4_IFADDR, err);
1957 }
1958
inet_get_link_af_size(const struct net_device * dev,u32 ext_filter_mask)1959 static size_t inet_get_link_af_size(const struct net_device *dev,
1960 u32 ext_filter_mask)
1961 {
1962 struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr);
1963
1964 if (!in_dev)
1965 return 0;
1966
1967 return nla_total_size(IPV4_DEVCONF_MAX * 4); /* IFLA_INET_CONF */
1968 }
1969
inet_fill_link_af(struct sk_buff * skb,const struct net_device * dev,u32 ext_filter_mask)1970 static int inet_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
1971 u32 ext_filter_mask)
1972 {
1973 struct in_device *in_dev = rcu_dereference_rtnl(dev->ip_ptr);
1974 struct nlattr *nla;
1975 int i;
1976
1977 if (!in_dev)
1978 return -ENODATA;
1979
1980 nla = nla_reserve(skb, IFLA_INET_CONF, IPV4_DEVCONF_MAX * 4);
1981 if (!nla)
1982 return -EMSGSIZE;
1983
1984 for (i = 0; i < IPV4_DEVCONF_MAX; i++)
1985 ((u32 *) nla_data(nla))[i] = in_dev->cnf.data[i];
1986
1987 return 0;
1988 }
1989
1990 static const struct nla_policy inet_af_policy[IFLA_INET_MAX+1] = {
1991 [IFLA_INET_CONF] = { .type = NLA_NESTED },
1992 };
1993
inet_validate_link_af(const struct net_device * dev,const struct nlattr * nla,struct netlink_ext_ack * extack)1994 static int inet_validate_link_af(const struct net_device *dev,
1995 const struct nlattr *nla,
1996 struct netlink_ext_ack *extack)
1997 {
1998 struct nlattr *a, *tb[IFLA_INET_MAX+1];
1999 int err, rem;
2000
2001 if (dev && !__in_dev_get_rtnl(dev))
2002 return -EAFNOSUPPORT;
2003
2004 err = nla_parse_nested_deprecated(tb, IFLA_INET_MAX, nla,
2005 inet_af_policy, extack);
2006 if (err < 0)
2007 return err;
2008
2009 if (tb[IFLA_INET_CONF]) {
2010 nla_for_each_nested(a, tb[IFLA_INET_CONF], rem) {
2011 int cfgid = nla_type(a);
2012
2013 if (nla_len(a) < 4)
2014 return -EINVAL;
2015
2016 if (cfgid <= 0 || cfgid > IPV4_DEVCONF_MAX)
2017 return -EINVAL;
2018 }
2019 }
2020
2021 return 0;
2022 }
2023
inet_set_link_af(struct net_device * dev,const struct nlattr * nla,struct netlink_ext_ack * extack)2024 static int inet_set_link_af(struct net_device *dev, const struct nlattr *nla,
2025 struct netlink_ext_ack *extack)
2026 {
2027 struct in_device *in_dev = __in_dev_get_rtnl(dev);
2028 struct nlattr *a, *tb[IFLA_INET_MAX+1];
2029 int rem;
2030
2031 if (!in_dev)
2032 return -EAFNOSUPPORT;
2033
2034 if (nla_parse_nested_deprecated(tb, IFLA_INET_MAX, nla, NULL, NULL) < 0)
2035 return -EINVAL;
2036
2037 if (tb[IFLA_INET_CONF]) {
2038 nla_for_each_nested(a, tb[IFLA_INET_CONF], rem)
2039 ipv4_devconf_set(in_dev, nla_type(a), nla_get_u32(a));
2040 }
2041
2042 return 0;
2043 }
2044
inet_netconf_msgsize_devconf(int type)2045 static int inet_netconf_msgsize_devconf(int type)
2046 {
2047 int size = NLMSG_ALIGN(sizeof(struct netconfmsg))
2048 + nla_total_size(4); /* NETCONFA_IFINDEX */
2049 bool all = false;
2050
2051 if (type == NETCONFA_ALL)
2052 all = true;
2053
2054 if (all || type == NETCONFA_FORWARDING)
2055 size += nla_total_size(4);
2056 if (all || type == NETCONFA_RP_FILTER)
2057 size += nla_total_size(4);
2058 if (all || type == NETCONFA_MC_FORWARDING)
2059 size += nla_total_size(4);
2060 if (all || type == NETCONFA_BC_FORWARDING)
2061 size += nla_total_size(4);
2062 if (all || type == NETCONFA_PROXY_NEIGH)
2063 size += nla_total_size(4);
2064 if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
2065 size += nla_total_size(4);
2066
2067 return size;
2068 }
2069
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)2070 static int inet_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
2071 struct ipv4_devconf *devconf, u32 portid,
2072 u32 seq, int event, unsigned int flags,
2073 int type)
2074 {
2075 struct nlmsghdr *nlh;
2076 struct netconfmsg *ncm;
2077 bool all = false;
2078
2079 nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
2080 flags);
2081 if (!nlh)
2082 return -EMSGSIZE;
2083
2084 if (type == NETCONFA_ALL)
2085 all = true;
2086
2087 ncm = nlmsg_data(nlh);
2088 ncm->ncm_family = AF_INET;
2089
2090 if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
2091 goto nla_put_failure;
2092
2093 if (!devconf)
2094 goto out;
2095
2096 if ((all || type == NETCONFA_FORWARDING) &&
2097 nla_put_s32(skb, NETCONFA_FORWARDING,
2098 IPV4_DEVCONF(*devconf, FORWARDING)) < 0)
2099 goto nla_put_failure;
2100 if ((all || type == NETCONFA_RP_FILTER) &&
2101 nla_put_s32(skb, NETCONFA_RP_FILTER,
2102 IPV4_DEVCONF(*devconf, RP_FILTER)) < 0)
2103 goto nla_put_failure;
2104 if ((all || type == NETCONFA_MC_FORWARDING) &&
2105 nla_put_s32(skb, NETCONFA_MC_FORWARDING,
2106 IPV4_DEVCONF(*devconf, MC_FORWARDING)) < 0)
2107 goto nla_put_failure;
2108 if ((all || type == NETCONFA_BC_FORWARDING) &&
2109 nla_put_s32(skb, NETCONFA_BC_FORWARDING,
2110 IPV4_DEVCONF(*devconf, BC_FORWARDING)) < 0)
2111 goto nla_put_failure;
2112 if ((all || type == NETCONFA_PROXY_NEIGH) &&
2113 nla_put_s32(skb, NETCONFA_PROXY_NEIGH,
2114 IPV4_DEVCONF(*devconf, PROXY_ARP)) < 0)
2115 goto nla_put_failure;
2116 if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
2117 nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
2118 IPV4_DEVCONF(*devconf, IGNORE_ROUTES_WITH_LINKDOWN)) < 0)
2119 goto nla_put_failure;
2120
2121 out:
2122 nlmsg_end(skb, nlh);
2123 return 0;
2124
2125 nla_put_failure:
2126 nlmsg_cancel(skb, nlh);
2127 return -EMSGSIZE;
2128 }
2129
inet_netconf_notify_devconf(struct net * net,int event,int type,int ifindex,struct ipv4_devconf * devconf)2130 void inet_netconf_notify_devconf(struct net *net, int event, int type,
2131 int ifindex, struct ipv4_devconf *devconf)
2132 {
2133 struct sk_buff *skb;
2134 int err = -ENOBUFS;
2135
2136 skb = nlmsg_new(inet_netconf_msgsize_devconf(type), GFP_KERNEL);
2137 if (!skb)
2138 goto errout;
2139
2140 err = inet_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
2141 event, 0, type);
2142 if (err < 0) {
2143 /* -EMSGSIZE implies BUG in inet_netconf_msgsize_devconf() */
2144 WARN_ON(err == -EMSGSIZE);
2145 kfree_skb(skb);
2146 goto errout;
2147 }
2148 rtnl_notify(skb, net, 0, RTNLGRP_IPV4_NETCONF, NULL, GFP_KERNEL);
2149 return;
2150 errout:
2151 if (err < 0)
2152 rtnl_set_sk_err(net, RTNLGRP_IPV4_NETCONF, err);
2153 }
2154
2155 static const struct nla_policy devconf_ipv4_policy[NETCONFA_MAX+1] = {
2156 [NETCONFA_IFINDEX] = { .len = sizeof(int) },
2157 [NETCONFA_FORWARDING] = { .len = sizeof(int) },
2158 [NETCONFA_RP_FILTER] = { .len = sizeof(int) },
2159 [NETCONFA_PROXY_NEIGH] = { .len = sizeof(int) },
2160 [NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN] = { .len = sizeof(int) },
2161 };
2162
inet_netconf_valid_get_req(struct sk_buff * skb,const struct nlmsghdr * nlh,struct nlattr ** tb,struct netlink_ext_ack * extack)2163 static int inet_netconf_valid_get_req(struct sk_buff *skb,
2164 const struct nlmsghdr *nlh,
2165 struct nlattr **tb,
2166 struct netlink_ext_ack *extack)
2167 {
2168 int i, err;
2169
2170 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
2171 NL_SET_ERR_MSG(extack, "ipv4: Invalid header for netconf get request");
2172 return -EINVAL;
2173 }
2174
2175 if (!netlink_strict_get_check(skb))
2176 return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
2177 tb, NETCONFA_MAX,
2178 devconf_ipv4_policy, extack);
2179
2180 err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
2181 tb, NETCONFA_MAX,
2182 devconf_ipv4_policy, extack);
2183 if (err)
2184 return err;
2185
2186 for (i = 0; i <= NETCONFA_MAX; i++) {
2187 if (!tb[i])
2188 continue;
2189
2190 switch (i) {
2191 case NETCONFA_IFINDEX:
2192 break;
2193 default:
2194 NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in netconf get request");
2195 return -EINVAL;
2196 }
2197 }
2198
2199 return 0;
2200 }
2201
inet_netconf_get_devconf(struct sk_buff * in_skb,struct nlmsghdr * nlh,struct netlink_ext_ack * extack)2202 static int inet_netconf_get_devconf(struct sk_buff *in_skb,
2203 struct nlmsghdr *nlh,
2204 struct netlink_ext_ack *extack)
2205 {
2206 struct net *net = sock_net(in_skb->sk);
2207 struct nlattr *tb[NETCONFA_MAX+1];
2208 struct sk_buff *skb;
2209 struct ipv4_devconf *devconf;
2210 struct in_device *in_dev;
2211 struct net_device *dev;
2212 int ifindex;
2213 int err;
2214
2215 err = inet_netconf_valid_get_req(in_skb, nlh, tb, extack);
2216 if (err)
2217 goto errout;
2218
2219 err = -EINVAL;
2220 if (!tb[NETCONFA_IFINDEX])
2221 goto errout;
2222
2223 ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
2224 switch (ifindex) {
2225 case NETCONFA_IFINDEX_ALL:
2226 devconf = net->ipv4.devconf_all;
2227 break;
2228 case NETCONFA_IFINDEX_DEFAULT:
2229 devconf = net->ipv4.devconf_dflt;
2230 break;
2231 default:
2232 dev = __dev_get_by_index(net, ifindex);
2233 if (!dev)
2234 goto errout;
2235 in_dev = __in_dev_get_rtnl(dev);
2236 if (!in_dev)
2237 goto errout;
2238 devconf = &in_dev->cnf;
2239 break;
2240 }
2241
2242 err = -ENOBUFS;
2243 skb = nlmsg_new(inet_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
2244 if (!skb)
2245 goto errout;
2246
2247 err = inet_netconf_fill_devconf(skb, ifindex, devconf,
2248 NETLINK_CB(in_skb).portid,
2249 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
2250 NETCONFA_ALL);
2251 if (err < 0) {
2252 /* -EMSGSIZE implies BUG in inet_netconf_msgsize_devconf() */
2253 WARN_ON(err == -EMSGSIZE);
2254 kfree_skb(skb);
2255 goto errout;
2256 }
2257 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
2258 errout:
2259 return err;
2260 }
2261
inet_netconf_dump_devconf(struct sk_buff * skb,struct netlink_callback * cb)2262 static int inet_netconf_dump_devconf(struct sk_buff *skb,
2263 struct netlink_callback *cb)
2264 {
2265 const struct nlmsghdr *nlh = cb->nlh;
2266 struct net *net = sock_net(skb->sk);
2267 int h, s_h;
2268 int idx, s_idx;
2269 struct net_device *dev;
2270 struct in_device *in_dev;
2271 struct hlist_head *head;
2272
2273 if (cb->strict_check) {
2274 struct netlink_ext_ack *extack = cb->extack;
2275 struct netconfmsg *ncm;
2276
2277 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
2278 NL_SET_ERR_MSG(extack, "ipv4: Invalid header for netconf dump request");
2279 return -EINVAL;
2280 }
2281
2282 if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
2283 NL_SET_ERR_MSG(extack, "ipv4: Invalid data after header in netconf dump request");
2284 return -EINVAL;
2285 }
2286 }
2287
2288 s_h = cb->args[0];
2289 s_idx = idx = cb->args[1];
2290
2291 for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
2292 idx = 0;
2293 head = &net->dev_index_head[h];
2294 rcu_read_lock();
2295 cb->seq = inet_base_seq(net);
2296 hlist_for_each_entry_rcu(dev, head, index_hlist) {
2297 if (idx < s_idx)
2298 goto cont;
2299 in_dev = __in_dev_get_rcu(dev);
2300 if (!in_dev)
2301 goto cont;
2302
2303 if (inet_netconf_fill_devconf(skb, dev->ifindex,
2304 &in_dev->cnf,
2305 NETLINK_CB(cb->skb).portid,
2306 nlh->nlmsg_seq,
2307 RTM_NEWNETCONF,
2308 NLM_F_MULTI,
2309 NETCONFA_ALL) < 0) {
2310 rcu_read_unlock();
2311 goto done;
2312 }
2313 nl_dump_check_consistent(cb, nlmsg_hdr(skb));
2314 cont:
2315 idx++;
2316 }
2317 rcu_read_unlock();
2318 }
2319 if (h == NETDEV_HASHENTRIES) {
2320 if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
2321 net->ipv4.devconf_all,
2322 NETLINK_CB(cb->skb).portid,
2323 nlh->nlmsg_seq,
2324 RTM_NEWNETCONF, NLM_F_MULTI,
2325 NETCONFA_ALL) < 0)
2326 goto done;
2327 else
2328 h++;
2329 }
2330 if (h == NETDEV_HASHENTRIES + 1) {
2331 if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
2332 net->ipv4.devconf_dflt,
2333 NETLINK_CB(cb->skb).portid,
2334 nlh->nlmsg_seq,
2335 RTM_NEWNETCONF, NLM_F_MULTI,
2336 NETCONFA_ALL) < 0)
2337 goto done;
2338 else
2339 h++;
2340 }
2341 done:
2342 cb->args[0] = h;
2343 cb->args[1] = idx;
2344
2345 return skb->len;
2346 }
2347
2348 #ifdef CONFIG_SYSCTL
2349
devinet_copy_dflt_conf(struct net * net,int i)2350 static void devinet_copy_dflt_conf(struct net *net, int i)
2351 {
2352 struct net_device *dev;
2353
2354 rcu_read_lock();
2355 for_each_netdev_rcu(net, dev) {
2356 struct in_device *in_dev;
2357
2358 in_dev = __in_dev_get_rcu(dev);
2359 if (in_dev && !test_bit(i, in_dev->cnf.state))
2360 in_dev->cnf.data[i] = net->ipv4.devconf_dflt->data[i];
2361 }
2362 rcu_read_unlock();
2363 }
2364
2365 /* called with RTNL locked */
inet_forward_change(struct net * net)2366 static void inet_forward_change(struct net *net)
2367 {
2368 struct net_device *dev;
2369 int on = IPV4_DEVCONF_ALL(net, FORWARDING);
2370
2371 IPV4_DEVCONF_ALL(net, ACCEPT_REDIRECTS) = !on;
2372 IPV4_DEVCONF_DFLT(net, FORWARDING) = on;
2373 inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
2374 NETCONFA_FORWARDING,
2375 NETCONFA_IFINDEX_ALL,
2376 net->ipv4.devconf_all);
2377 inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
2378 NETCONFA_FORWARDING,
2379 NETCONFA_IFINDEX_DEFAULT,
2380 net->ipv4.devconf_dflt);
2381
2382 for_each_netdev(net, dev) {
2383 struct in_device *in_dev;
2384
2385 if (on)
2386 dev_disable_lro(dev);
2387
2388 in_dev = __in_dev_get_rtnl(dev);
2389 if (in_dev) {
2390 IN_DEV_CONF_SET(in_dev, FORWARDING, on);
2391 inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
2392 NETCONFA_FORWARDING,
2393 dev->ifindex, &in_dev->cnf);
2394 }
2395 }
2396 }
2397
devinet_conf_ifindex(struct net * net,struct ipv4_devconf * cnf)2398 static int devinet_conf_ifindex(struct net *net, struct ipv4_devconf *cnf)
2399 {
2400 if (cnf == net->ipv4.devconf_dflt)
2401 return NETCONFA_IFINDEX_DEFAULT;
2402 else if (cnf == net->ipv4.devconf_all)
2403 return NETCONFA_IFINDEX_ALL;
2404 else {
2405 struct in_device *idev
2406 = container_of(cnf, struct in_device, cnf);
2407 return idev->dev->ifindex;
2408 }
2409 }
2410
devinet_conf_proc(struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)2411 static int devinet_conf_proc(struct ctl_table *ctl, int write,
2412 void *buffer, size_t *lenp, loff_t *ppos)
2413 {
2414 int old_value = *(int *)ctl->data;
2415 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
2416 int new_value = *(int *)ctl->data;
2417
2418 if (write) {
2419 struct ipv4_devconf *cnf = ctl->extra1;
2420 struct net *net = ctl->extra2;
2421 int i = (int *)ctl->data - cnf->data;
2422 int ifindex;
2423
2424 set_bit(i, cnf->state);
2425
2426 if (cnf == net->ipv4.devconf_dflt)
2427 devinet_copy_dflt_conf(net, i);
2428 if (i == IPV4_DEVCONF_ACCEPT_LOCAL - 1 ||
2429 i == IPV4_DEVCONF_ROUTE_LOCALNET - 1)
2430 if ((new_value == 0) && (old_value != 0))
2431 rt_cache_flush(net);
2432
2433 if (i == IPV4_DEVCONF_BC_FORWARDING - 1 &&
2434 new_value != old_value)
2435 rt_cache_flush(net);
2436
2437 if (i == IPV4_DEVCONF_RP_FILTER - 1 &&
2438 new_value != old_value) {
2439 ifindex = devinet_conf_ifindex(net, cnf);
2440 inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
2441 NETCONFA_RP_FILTER,
2442 ifindex, cnf);
2443 }
2444 if (i == IPV4_DEVCONF_PROXY_ARP - 1 &&
2445 new_value != old_value) {
2446 ifindex = devinet_conf_ifindex(net, cnf);
2447 inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
2448 NETCONFA_PROXY_NEIGH,
2449 ifindex, cnf);
2450 }
2451 if (i == IPV4_DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN - 1 &&
2452 new_value != old_value) {
2453 ifindex = devinet_conf_ifindex(net, cnf);
2454 inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
2455 NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
2456 ifindex, cnf);
2457 }
2458 }
2459
2460 return ret;
2461 }
2462
devinet_sysctl_forward(struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)2463 static int devinet_sysctl_forward(struct ctl_table *ctl, int write,
2464 void *buffer, size_t *lenp, loff_t *ppos)
2465 {
2466 int *valp = ctl->data;
2467 int val = *valp;
2468 loff_t pos = *ppos;
2469 struct net *net = ctl->extra2;
2470 int ret;
2471
2472 if (write && !ns_capable(net->user_ns, CAP_NET_ADMIN))
2473 return -EPERM;
2474
2475 ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
2476
2477 if (write && *valp != val) {
2478 if (valp != &IPV4_DEVCONF_DFLT(net, FORWARDING)) {
2479 if (!rtnl_trylock()) {
2480 /* Restore the original values before restarting */
2481 *valp = val;
2482 *ppos = pos;
2483 return restart_syscall();
2484 }
2485 if (valp == &IPV4_DEVCONF_ALL(net, FORWARDING)) {
2486 inet_forward_change(net);
2487 } else {
2488 struct ipv4_devconf *cnf = ctl->extra1;
2489 struct in_device *idev =
2490 container_of(cnf, struct in_device, cnf);
2491 if (*valp)
2492 dev_disable_lro(idev->dev);
2493 inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
2494 NETCONFA_FORWARDING,
2495 idev->dev->ifindex,
2496 cnf);
2497 }
2498 rtnl_unlock();
2499 rt_cache_flush(net);
2500 } else
2501 inet_netconf_notify_devconf(net, RTM_NEWNETCONF,
2502 NETCONFA_FORWARDING,
2503 NETCONFA_IFINDEX_DEFAULT,
2504 net->ipv4.devconf_dflt);
2505 }
2506
2507 return ret;
2508 }
2509
ipv4_doint_and_flush(struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)2510 static int ipv4_doint_and_flush(struct ctl_table *ctl, int write,
2511 void *buffer, size_t *lenp, loff_t *ppos)
2512 {
2513 int *valp = ctl->data;
2514 int val = *valp;
2515 int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
2516 struct net *net = ctl->extra2;
2517
2518 if (write && *valp != val)
2519 rt_cache_flush(net);
2520
2521 return ret;
2522 }
2523
2524 #define DEVINET_SYSCTL_ENTRY(attr, name, mval, proc) \
2525 { \
2526 .procname = name, \
2527 .data = ipv4_devconf.data + \
2528 IPV4_DEVCONF_ ## attr - 1, \
2529 .maxlen = sizeof(int), \
2530 .mode = mval, \
2531 .proc_handler = proc, \
2532 .extra1 = &ipv4_devconf, \
2533 }
2534
2535 #define DEVINET_SYSCTL_RW_ENTRY(attr, name) \
2536 DEVINET_SYSCTL_ENTRY(attr, name, 0644, devinet_conf_proc)
2537
2538 #define DEVINET_SYSCTL_RO_ENTRY(attr, name) \
2539 DEVINET_SYSCTL_ENTRY(attr, name, 0444, devinet_conf_proc)
2540
2541 #define DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, proc) \
2542 DEVINET_SYSCTL_ENTRY(attr, name, 0644, proc)
2543
2544 #define DEVINET_SYSCTL_FLUSHING_ENTRY(attr, name) \
2545 DEVINET_SYSCTL_COMPLEX_ENTRY(attr, name, ipv4_doint_and_flush)
2546
2547 static struct devinet_sysctl_table {
2548 struct ctl_table_header *sysctl_header;
2549 struct ctl_table devinet_vars[__IPV4_DEVCONF_MAX];
2550 } devinet_sysctl = {
2551 .devinet_vars = {
2552 DEVINET_SYSCTL_COMPLEX_ENTRY(FORWARDING, "forwarding",
2553 devinet_sysctl_forward),
2554 DEVINET_SYSCTL_RO_ENTRY(MC_FORWARDING, "mc_forwarding"),
2555 DEVINET_SYSCTL_RW_ENTRY(BC_FORWARDING, "bc_forwarding"),
2556
2557 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_REDIRECTS, "accept_redirects"),
2558 DEVINET_SYSCTL_RW_ENTRY(SECURE_REDIRECTS, "secure_redirects"),
2559 DEVINET_SYSCTL_RW_ENTRY(SHARED_MEDIA, "shared_media"),
2560 DEVINET_SYSCTL_RW_ENTRY(RP_FILTER, "rp_filter"),
2561 DEVINET_SYSCTL_RW_ENTRY(SEND_REDIRECTS, "send_redirects"),
2562 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_SOURCE_ROUTE,
2563 "accept_source_route"),
2564 DEVINET_SYSCTL_RW_ENTRY(ACCEPT_LOCAL, "accept_local"),
2565 DEVINET_SYSCTL_RW_ENTRY(SRC_VMARK, "src_valid_mark"),
2566 DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP, "proxy_arp"),
2567 DEVINET_SYSCTL_RW_ENTRY(MEDIUM_ID, "medium_id"),
2568 DEVINET_SYSCTL_RW_ENTRY(BOOTP_RELAY, "bootp_relay"),
2569 DEVINET_SYSCTL_RW_ENTRY(LOG_MARTIANS, "log_martians"),
2570 DEVINET_SYSCTL_RW_ENTRY(TAG, "tag"),
2571 DEVINET_SYSCTL_RW_ENTRY(ARPFILTER, "arp_filter"),
2572 DEVINET_SYSCTL_RW_ENTRY(ARP_ANNOUNCE, "arp_announce"),
2573 DEVINET_SYSCTL_RW_ENTRY(ARP_IGNORE, "arp_ignore"),
2574 DEVINET_SYSCTL_RW_ENTRY(ARP_ACCEPT, "arp_accept"),
2575 DEVINET_SYSCTL_RW_ENTRY(ARP_NOTIFY, "arp_notify"),
2576 DEVINET_SYSCTL_RW_ENTRY(ARP_EVICT_NOCARRIER,
2577 "arp_evict_nocarrier"),
2578 DEVINET_SYSCTL_RW_ENTRY(PROXY_ARP_PVLAN, "proxy_arp_pvlan"),
2579 DEVINET_SYSCTL_RW_ENTRY(FORCE_IGMP_VERSION,
2580 "force_igmp_version"),
2581 DEVINET_SYSCTL_RW_ENTRY(IGMPV2_UNSOLICITED_REPORT_INTERVAL,
2582 "igmpv2_unsolicited_report_interval"),
2583 DEVINET_SYSCTL_RW_ENTRY(IGMPV3_UNSOLICITED_REPORT_INTERVAL,
2584 "igmpv3_unsolicited_report_interval"),
2585 DEVINET_SYSCTL_RW_ENTRY(IGNORE_ROUTES_WITH_LINKDOWN,
2586 "ignore_routes_with_linkdown"),
2587 DEVINET_SYSCTL_RW_ENTRY(DROP_GRATUITOUS_ARP,
2588 "drop_gratuitous_arp"),
2589
2590 DEVINET_SYSCTL_FLUSHING_ENTRY(NOXFRM, "disable_xfrm"),
2591 DEVINET_SYSCTL_FLUSHING_ENTRY(NOPOLICY, "disable_policy"),
2592 DEVINET_SYSCTL_FLUSHING_ENTRY(PROMOTE_SECONDARIES,
2593 "promote_secondaries"),
2594 DEVINET_SYSCTL_FLUSHING_ENTRY(ROUTE_LOCALNET,
2595 "route_localnet"),
2596 DEVINET_SYSCTL_FLUSHING_ENTRY(DROP_UNICAST_IN_L2_MULTICAST,
2597 "drop_unicast_in_l2_multicast"),
2598 },
2599 };
2600
__devinet_sysctl_register(struct net * net,char * dev_name,int ifindex,struct ipv4_devconf * p)2601 static int __devinet_sysctl_register(struct net *net, char *dev_name,
2602 int ifindex, struct ipv4_devconf *p)
2603 {
2604 int i;
2605 struct devinet_sysctl_table *t;
2606 char path[sizeof("net/ipv4/conf/") + IFNAMSIZ];
2607
2608 t = kmemdup(&devinet_sysctl, sizeof(*t), GFP_KERNEL_ACCOUNT);
2609 if (!t)
2610 goto out;
2611
2612 for (i = 0; i < ARRAY_SIZE(t->devinet_vars) - 1; i++) {
2613 t->devinet_vars[i].data += (char *)p - (char *)&ipv4_devconf;
2614 t->devinet_vars[i].extra1 = p;
2615 t->devinet_vars[i].extra2 = net;
2616 }
2617
2618 snprintf(path, sizeof(path), "net/ipv4/conf/%s", dev_name);
2619
2620 t->sysctl_header = register_net_sysctl(net, path, t->devinet_vars);
2621 if (!t->sysctl_header)
2622 goto free;
2623
2624 p->sysctl = t;
2625
2626 inet_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
2627 ifindex, p);
2628 return 0;
2629
2630 free:
2631 kfree(t);
2632 out:
2633 return -ENOMEM;
2634 }
2635
__devinet_sysctl_unregister(struct net * net,struct ipv4_devconf * cnf,int ifindex)2636 static void __devinet_sysctl_unregister(struct net *net,
2637 struct ipv4_devconf *cnf, int ifindex)
2638 {
2639 struct devinet_sysctl_table *t = cnf->sysctl;
2640
2641 if (t) {
2642 cnf->sysctl = NULL;
2643 unregister_net_sysctl_table(t->sysctl_header);
2644 kfree(t);
2645 }
2646
2647 inet_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
2648 }
2649
devinet_sysctl_register(struct in_device * idev)2650 static int devinet_sysctl_register(struct in_device *idev)
2651 {
2652 int err;
2653
2654 if (!sysctl_dev_name_is_allowed(idev->dev->name))
2655 return -EINVAL;
2656
2657 err = neigh_sysctl_register(idev->dev, idev->arp_parms, NULL);
2658 if (err)
2659 return err;
2660 err = __devinet_sysctl_register(dev_net(idev->dev), idev->dev->name,
2661 idev->dev->ifindex, &idev->cnf);
2662 if (err)
2663 neigh_sysctl_unregister(idev->arp_parms);
2664 return err;
2665 }
2666
devinet_sysctl_unregister(struct in_device * idev)2667 static void devinet_sysctl_unregister(struct in_device *idev)
2668 {
2669 struct net *net = dev_net(idev->dev);
2670
2671 __devinet_sysctl_unregister(net, &idev->cnf, idev->dev->ifindex);
2672 neigh_sysctl_unregister(idev->arp_parms);
2673 }
2674
2675 static struct ctl_table ctl_forward_entry[] = {
2676 {
2677 .procname = "ip_forward",
2678 .data = &ipv4_devconf.data[
2679 IPV4_DEVCONF_FORWARDING - 1],
2680 .maxlen = sizeof(int),
2681 .mode = 0644,
2682 .proc_handler = devinet_sysctl_forward,
2683 .extra1 = &ipv4_devconf,
2684 .extra2 = &init_net,
2685 },
2686 { },
2687 };
2688 #endif
2689
devinet_init_net(struct net * net)2690 static __net_init int devinet_init_net(struct net *net)
2691 {
2692 int err;
2693 struct ipv4_devconf *all, *dflt;
2694 #ifdef CONFIG_SYSCTL
2695 struct ctl_table *tbl;
2696 struct ctl_table_header *forw_hdr;
2697 #endif
2698
2699 err = -ENOMEM;
2700 all = kmemdup(&ipv4_devconf, sizeof(ipv4_devconf), GFP_KERNEL);
2701 if (!all)
2702 goto err_alloc_all;
2703
2704 dflt = kmemdup(&ipv4_devconf_dflt, sizeof(ipv4_devconf_dflt), GFP_KERNEL);
2705 if (!dflt)
2706 goto err_alloc_dflt;
2707
2708 #ifdef CONFIG_SYSCTL
2709 tbl = kmemdup(ctl_forward_entry, sizeof(ctl_forward_entry), GFP_KERNEL);
2710 if (!tbl)
2711 goto err_alloc_ctl;
2712
2713 tbl[0].data = &all->data[IPV4_DEVCONF_FORWARDING - 1];
2714 tbl[0].extra1 = all;
2715 tbl[0].extra2 = net;
2716 #endif
2717
2718 if (!net_eq(net, &init_net)) {
2719 switch (net_inherit_devconf()) {
2720 case 3:
2721 /* copy from the current netns */
2722 memcpy(all, current->nsproxy->net_ns->ipv4.devconf_all,
2723 sizeof(ipv4_devconf));
2724 memcpy(dflt,
2725 current->nsproxy->net_ns->ipv4.devconf_dflt,
2726 sizeof(ipv4_devconf_dflt));
2727 break;
2728 case 0:
2729 case 1:
2730 /* copy from init_net */
2731 memcpy(all, init_net.ipv4.devconf_all,
2732 sizeof(ipv4_devconf));
2733 memcpy(dflt, init_net.ipv4.devconf_dflt,
2734 sizeof(ipv4_devconf_dflt));
2735 break;
2736 case 2:
2737 /* use compiled values */
2738 break;
2739 }
2740 }
2741
2742 #ifdef CONFIG_SYSCTL
2743 err = __devinet_sysctl_register(net, "all", NETCONFA_IFINDEX_ALL, all);
2744 if (err < 0)
2745 goto err_reg_all;
2746
2747 err = __devinet_sysctl_register(net, "default",
2748 NETCONFA_IFINDEX_DEFAULT, dflt);
2749 if (err < 0)
2750 goto err_reg_dflt;
2751
2752 err = -ENOMEM;
2753 forw_hdr = register_net_sysctl_sz(net, "net/ipv4", tbl,
2754 ARRAY_SIZE(ctl_forward_entry));
2755 if (!forw_hdr)
2756 goto err_reg_ctl;
2757 net->ipv4.forw_hdr = forw_hdr;
2758 #endif
2759
2760 net->ipv4.devconf_all = all;
2761 net->ipv4.devconf_dflt = dflt;
2762 return 0;
2763
2764 #ifdef CONFIG_SYSCTL
2765 err_reg_ctl:
2766 __devinet_sysctl_unregister(net, dflt, NETCONFA_IFINDEX_DEFAULT);
2767 err_reg_dflt:
2768 __devinet_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
2769 err_reg_all:
2770 kfree(tbl);
2771 err_alloc_ctl:
2772 #endif
2773 kfree(dflt);
2774 err_alloc_dflt:
2775 kfree(all);
2776 err_alloc_all:
2777 return err;
2778 }
2779
devinet_exit_net(struct net * net)2780 static __net_exit void devinet_exit_net(struct net *net)
2781 {
2782 #ifdef CONFIG_SYSCTL
2783 struct ctl_table *tbl;
2784
2785 tbl = net->ipv4.forw_hdr->ctl_table_arg;
2786 unregister_net_sysctl_table(net->ipv4.forw_hdr);
2787 __devinet_sysctl_unregister(net, net->ipv4.devconf_dflt,
2788 NETCONFA_IFINDEX_DEFAULT);
2789 __devinet_sysctl_unregister(net, net->ipv4.devconf_all,
2790 NETCONFA_IFINDEX_ALL);
2791 kfree(tbl);
2792 #endif
2793 kfree(net->ipv4.devconf_dflt);
2794 kfree(net->ipv4.devconf_all);
2795 }
2796
2797 static __net_initdata struct pernet_operations devinet_ops = {
2798 .init = devinet_init_net,
2799 .exit = devinet_exit_net,
2800 };
2801
2802 static struct rtnl_af_ops inet_af_ops __read_mostly = {
2803 .family = AF_INET,
2804 .fill_link_af = inet_fill_link_af,
2805 .get_link_af_size = inet_get_link_af_size,
2806 .validate_link_af = inet_validate_link_af,
2807 .set_link_af = inet_set_link_af,
2808 };
2809
devinet_init(void)2810 void __init devinet_init(void)
2811 {
2812 int i;
2813
2814 for (i = 0; i < IN4_ADDR_HSIZE; i++)
2815 INIT_HLIST_HEAD(&inet_addr_lst[i]);
2816
2817 register_pernet_subsys(&devinet_ops);
2818 register_netdevice_notifier(&ip_netdev_notifier);
2819
2820 queue_delayed_work(system_power_efficient_wq, &check_lifetime_work, 0);
2821
2822 rtnl_af_register(&inet_af_ops);
2823
2824 rtnl_register(PF_INET, RTM_NEWADDR, inet_rtm_newaddr, NULL, 0);
2825 rtnl_register(PF_INET, RTM_DELADDR, inet_rtm_deladdr, NULL, 0);
2826 rtnl_register(PF_INET, RTM_GETADDR, NULL, inet_dump_ifaddr, 0);
2827 rtnl_register(PF_INET, RTM_GETNETCONF, inet_netconf_get_devconf,
2828 inet_netconf_dump_devconf, 0);
2829 }
2830