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perf bpf: Move perf_event_output() from stdio.h to bpf.h
[linux/fpc-iii.git] / net / ipv4 / fib_frontend.c
blob6df95be963116ced81f70e5fb51bfe6114e8965a
1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * IPv4 Forwarding Information Base: FIB frontend.
7 *
8 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
14 */
15
16 #include <linux/module.h>
17 #include <linux/uaccess.h>
18 #include <linux/bitops.h>
19 #include <linux/capability.h>
20 #include <linux/types.h>
21 #include <linux/kernel.h>
22 #include <linux/mm.h>
23 #include <linux/string.h>
24 #include <linux/socket.h>
25 #include <linux/sockios.h>
26 #include <linux/errno.h>
27 #include <linux/in.h>
28 #include <linux/inet.h>
29 #include <linux/inetdevice.h>
30 #include <linux/netdevice.h>
31 #include <linux/if_addr.h>
32 #include <linux/if_arp.h>
33 #include <linux/skbuff.h>
34 #include <linux/cache.h>
35 #include <linux/init.h>
36 #include <linux/list.h>
37 #include <linux/slab.h>
38
39 #include <net/ip.h>
40 #include <net/protocol.h>
41 #include <net/route.h>
42 #include <net/tcp.h>
43 #include <net/sock.h>
44 #include <net/arp.h>
45 #include <net/ip_fib.h>
46 #include <net/rtnetlink.h>
47 #include <net/xfrm.h>
48 #include <net/l3mdev.h>
49 #include <net/lwtunnel.h>
50 #include <trace/events/fib.h>
51
52 #ifndef CONFIG_IP_MULTIPLE_TABLES
53
54 static int __net_init fib4_rules_init(struct net *net)
55 {
56 struct fib_table *local_table, *main_table;
57
58 main_table = fib_trie_table(RT_TABLE_MAIN, NULL);
59 if (!main_table)
60 return -ENOMEM;
61
62 local_table = fib_trie_table(RT_TABLE_LOCAL, main_table);
63 if (!local_table)
64 goto fail;
65
66 hlist_add_head_rcu(&local_table->tb_hlist,
67 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX]);
68 hlist_add_head_rcu(&main_table->tb_hlist,
69 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX]);
70 return 0;
71
72 fail:
73 fib_free_table(main_table);
74 return -ENOMEM;
75 }
76
77 static bool fib4_has_custom_rules(struct net *net)
78 {
79 return false;
80 }
81 #else
82
83 struct fib_table *fib_new_table(struct net *net, u32 id)
84 {
85 struct fib_table *tb, *alias = NULL;
86 unsigned int h;
87
88 if (id == 0)
89 id = RT_TABLE_MAIN;
90 tb = fib_get_table(net, id);
91 if (tb)
92 return tb;
93
94 if (id == RT_TABLE_LOCAL && !net->ipv4.fib_has_custom_rules)
95 alias = fib_new_table(net, RT_TABLE_MAIN);
96
97 tb = fib_trie_table(id, alias);
98 if (!tb)
99 return NULL;
100
101 switch (id) {
102 case RT_TABLE_MAIN:
103 rcu_assign_pointer(net->ipv4.fib_main, tb);
104 break;
105 case RT_TABLE_DEFAULT:
106 rcu_assign_pointer(net->ipv4.fib_default, tb);
107 break;
108 default:
109 break;
110 }
111
112 h = id & (FIB_TABLE_HASHSZ - 1);
113 hlist_add_head_rcu(&tb->tb_hlist, &net->ipv4.fib_table_hash[h]);
114 return tb;
115 }
116 EXPORT_SYMBOL_GPL(fib_new_table);
117
118 /* caller must hold either rtnl or rcu read lock */
119 struct fib_table *fib_get_table(struct net *net, u32 id)
120 {
121 struct fib_table *tb;
122 struct hlist_head *head;
123 unsigned int h;
124
125 if (id == 0)
126 id = RT_TABLE_MAIN;
127 h = id & (FIB_TABLE_HASHSZ - 1);
128
129 head = &net->ipv4.fib_table_hash[h];
130 hlist_for_each_entry_rcu(tb, head, tb_hlist) {
131 if (tb->tb_id == id)
132 return tb;
133 }
134 return NULL;
135 }
136
137 static bool fib4_has_custom_rules(struct net *net)
138 {
139 return net->ipv4.fib_has_custom_rules;
140 }
141 #endif /* CONFIG_IP_MULTIPLE_TABLES */
142
143 static void fib_replace_table(struct net *net, struct fib_table *old,
144 struct fib_table *new)
145 {
146 #ifdef CONFIG_IP_MULTIPLE_TABLES
147 switch (new->tb_id) {
148 case RT_TABLE_MAIN:
149 rcu_assign_pointer(net->ipv4.fib_main, new);
150 break;
151 case RT_TABLE_DEFAULT:
152 rcu_assign_pointer(net->ipv4.fib_default, new);
153 break;
154 default:
155 break;
156 }
157
158 #endif
159 /* replace the old table in the hlist */
160 hlist_replace_rcu(&old->tb_hlist, &new->tb_hlist);
161 }
162
163 int fib_unmerge(struct net *net)
164 {
165 struct fib_table *old, *new, *main_table;
166
167 /* attempt to fetch local table if it has been allocated */
168 old = fib_get_table(net, RT_TABLE_LOCAL);
169 if (!old)
170 return 0;
171
172 new = fib_trie_unmerge(old);
173 if (!new)
174 return -ENOMEM;
175
176 /* table is already unmerged */
177 if (new == old)
178 return 0;
179
180 /* replace merged table with clean table */
181 fib_replace_table(net, old, new);
182 fib_free_table(old);
183
184 /* attempt to fetch main table if it has been allocated */
185 main_table = fib_get_table(net, RT_TABLE_MAIN);
186 if (!main_table)
187 return 0;
188
189 /* flush local entries from main table */
190 fib_table_flush_external(main_table);
191
192 return 0;
193 }
194
195 static void fib_flush(struct net *net)
196 {
197 int flushed = 0;
198 unsigned int h;
199
200 for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
201 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
202 struct hlist_node *tmp;
203 struct fib_table *tb;
204
205 hlist_for_each_entry_safe(tb, tmp, head, tb_hlist)
206 flushed += fib_table_flush(net, tb);
207 }
208
209 if (flushed)
210 rt_cache_flush(net);
211 }
212
213 /*
214 * Find address type as if only "dev" was present in the system. If
215 * on_dev is NULL then all interfaces are taken into consideration.
216 */
217 static inline unsigned int __inet_dev_addr_type(struct net *net,
218 const struct net_device *dev,
219 __be32 addr, u32 tb_id)
220 {
221 struct flowi4 fl4 = { .daddr = addr };
222 struct fib_result res;
223 unsigned int ret = RTN_BROADCAST;
224 struct fib_table *table;
225
226 if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr))
227 return RTN_BROADCAST;
228 if (ipv4_is_multicast(addr))
229 return RTN_MULTICAST;
230
231 rcu_read_lock();
232
233 table = fib_get_table(net, tb_id);
234 if (table) {
235 ret = RTN_UNICAST;
236 if (!fib_table_lookup(table, &fl4, &res, FIB_LOOKUP_NOREF)) {
237 if (!dev || dev == res.fi->fib_dev)
238 ret = res.type;
239 }
240 }
241
242 rcu_read_unlock();
243 return ret;
244 }
245
246 unsigned int inet_addr_type_table(struct net *net, __be32 addr, u32 tb_id)
247 {
248 return __inet_dev_addr_type(net, NULL, addr, tb_id);
249 }
250 EXPORT_SYMBOL(inet_addr_type_table);
251
252 unsigned int inet_addr_type(struct net *net, __be32 addr)
253 {
254 return __inet_dev_addr_type(net, NULL, addr, RT_TABLE_LOCAL);
255 }
256 EXPORT_SYMBOL(inet_addr_type);
257
258 unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev,
259 __be32 addr)
260 {
261 u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL;
262
263 return __inet_dev_addr_type(net, dev, addr, rt_table);
264 }
265 EXPORT_SYMBOL(inet_dev_addr_type);
266
267 /* inet_addr_type with dev == NULL but using the table from a dev
268 * if one is associated
269 */
270 unsigned int inet_addr_type_dev_table(struct net *net,
271 const struct net_device *dev,
272 __be32 addr)
273 {
274 u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL;
275
276 return __inet_dev_addr_type(net, NULL, addr, rt_table);
277 }
278 EXPORT_SYMBOL(inet_addr_type_dev_table);
279
280 __be32 fib_compute_spec_dst(struct sk_buff *skb)
281 {
282 struct net_device *dev = skb->dev;
283 struct in_device *in_dev;
284 struct fib_result res;
285 struct rtable *rt;
286 struct net *net;
287 int scope;
288
289 rt = skb_rtable(skb);
290 if ((rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST | RTCF_LOCAL)) ==
291 RTCF_LOCAL)
292 return ip_hdr(skb)->daddr;
293
294 in_dev = __in_dev_get_rcu(dev);
295
296 net = dev_net(dev);
297
298 scope = RT_SCOPE_UNIVERSE;
299 if (!ipv4_is_zeronet(ip_hdr(skb)->saddr)) {
300 bool vmark = in_dev && IN_DEV_SRC_VMARK(in_dev);
301 struct flowi4 fl4 = {
302 .flowi4_iif = LOOPBACK_IFINDEX,
303 .flowi4_oif = l3mdev_master_ifindex_rcu(dev),
304 .daddr = ip_hdr(skb)->saddr,
305 .flowi4_tos = RT_TOS(ip_hdr(skb)->tos),
306 .flowi4_scope = scope,
307 .flowi4_mark = vmark ? skb->mark : 0,
308 };
309 if (!fib_lookup(net, &fl4, &res, 0))
310 return FIB_RES_PREFSRC(net, res);
311 } else {
312 scope = RT_SCOPE_LINK;
313 }
314
315 return inet_select_addr(dev, ip_hdr(skb)->saddr, scope);
316 }
317
318 bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev)
319 {
320 bool dev_match = false;
321 #ifdef CONFIG_IP_ROUTE_MULTIPATH
322 int ret;
323
324 for (ret = 0; ret < fi->fib_nhs; ret++) {
325 struct fib_nh *nh = &fi->fib_nh[ret];
326
327 if (nh->nh_dev == dev) {
328 dev_match = true;
329 break;
330 } else if (l3mdev_master_ifindex_rcu(nh->nh_dev) == dev->ifindex) {
331 dev_match = true;
332 break;
333 }
334 }
335 #else
336 if (fi->fib_nh[0].nh_dev == dev)
337 dev_match = true;
338 #endif
339
340 return dev_match;
341 }
342 EXPORT_SYMBOL_GPL(fib_info_nh_uses_dev);
343
344 /* Given (packet source, input interface) and optional (dst, oif, tos):
345 * - (main) check, that source is valid i.e. not broadcast or our local
346 * address.
347 * - figure out what "logical" interface this packet arrived
348 * and calculate "specific destination" address.
349 * - check, that packet arrived from expected physical interface.
350 * called with rcu_read_lock()
351 */
352 static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
353 u8 tos, int oif, struct net_device *dev,
354 int rpf, struct in_device *idev, u32 *itag)
355 {
356 struct net *net = dev_net(dev);
357 struct flow_keys flkeys;
358 int ret, no_addr;
359 struct fib_result res;
360 struct flowi4 fl4;
361 bool dev_match;
362
363 fl4.flowi4_oif = 0;
364 fl4.flowi4_iif = l3mdev_master_ifindex_rcu(dev);
365 if (!fl4.flowi4_iif)
366 fl4.flowi4_iif = oif ? : LOOPBACK_IFINDEX;
367 fl4.daddr = src;
368 fl4.saddr = dst;
369 fl4.flowi4_tos = tos;
370 fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
371 fl4.flowi4_tun_key.tun_id = 0;
372 fl4.flowi4_flags = 0;
373 fl4.flowi4_uid = sock_net_uid(net, NULL);
374
375 no_addr = idev->ifa_list == NULL;
376
377 fl4.flowi4_mark = IN_DEV_SRC_VMARK(idev) ? skb->mark : 0;
378 if (!fib4_rules_early_flow_dissect(net, skb, &fl4, &flkeys)) {
379 fl4.flowi4_proto = 0;
380 fl4.fl4_sport = 0;
381 fl4.fl4_dport = 0;
382 }
383
384 if (fib_lookup(net, &fl4, &res, 0))
385 goto last_resort;
386 if (res.type != RTN_UNICAST &&
387 (res.type != RTN_LOCAL || !IN_DEV_ACCEPT_LOCAL(idev)))
388 goto e_inval;
389 fib_combine_itag(itag, &res);
390
391 dev_match = fib_info_nh_uses_dev(res.fi, dev);
392 if (dev_match) {
393 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
394 return ret;
395 }
396 if (no_addr)
397 goto last_resort;
398 if (rpf == 1)
399 goto e_rpf;
400 fl4.flowi4_oif = dev->ifindex;
401
402 ret = 0;
403 if (fib_lookup(net, &fl4, &res, FIB_LOOKUP_IGNORE_LINKSTATE) == 0) {
404 if (res.type == RTN_UNICAST)
405 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
406 }
407 return ret;
408
409 last_resort:
410 if (rpf)
411 goto e_rpf;
412 *itag = 0;
413 return 0;
414
415 e_inval:
416 return -EINVAL;
417 e_rpf:
418 return -EXDEV;
419 }
420
421 /* Ignore rp_filter for packets protected by IPsec. */
422 int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
423 u8 tos, int oif, struct net_device *dev,
424 struct in_device *idev, u32 *itag)
425 {
426 int r = secpath_exists(skb) ? 0 : IN_DEV_RPFILTER(idev);
427 struct net *net = dev_net(dev);
428
429 if (!r && !fib_num_tclassid_users(net) &&
430 (dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev))) {
431 if (IN_DEV_ACCEPT_LOCAL(idev))
432 goto ok;
433 /* with custom local routes in place, checking local addresses
434 * only will be too optimistic, with custom rules, checking
435 * local addresses only can be too strict, e.g. due to vrf
436 */
437 if (net->ipv4.fib_has_custom_local_routes ||
438 fib4_has_custom_rules(net))
439 goto full_check;
440 if (inet_lookup_ifaddr_rcu(net, src))
441 return -EINVAL;
442
443 ok:
444 *itag = 0;
445 return 0;
446 }
447
448 full_check:
449 return __fib_validate_source(skb, src, dst, tos, oif, dev, r, idev, itag);
450 }
451
452 static inline __be32 sk_extract_addr(struct sockaddr *addr)
453 {
454 return ((struct sockaddr_in *) addr)->sin_addr.s_addr;
455 }
456
457 static int put_rtax(struct nlattr *mx, int len, int type, u32 value)
458 {
459 struct nlattr *nla;
460
461 nla = (struct nlattr *) ((char *) mx + len);
462 nla->nla_type = type;
463 nla->nla_len = nla_attr_size(4);
464 *(u32 *) nla_data(nla) = value;
465
466 return len + nla_total_size(4);
467 }
468
469 static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt,
470 struct fib_config *cfg)
471 {
472 __be32 addr;
473 int plen;
474
475 memset(cfg, 0, sizeof(*cfg));
476 cfg->fc_nlinfo.nl_net = net;
477
478 if (rt->rt_dst.sa_family != AF_INET)
479 return -EAFNOSUPPORT;
480
481 /*
482 * Check mask for validity:
483 * a) it must be contiguous.
484 * b) destination must have all host bits clear.
485 * c) if application forgot to set correct family (AF_INET),
486 * reject request unless it is absolutely clear i.e.
487 * both family and mask are zero.
488 */
489 plen = 32;
490 addr = sk_extract_addr(&rt->rt_dst);
491 if (!(rt->rt_flags & RTF_HOST)) {
492 __be32 mask = sk_extract_addr(&rt->rt_genmask);
493
494 if (rt->rt_genmask.sa_family != AF_INET) {
495 if (mask || rt->rt_genmask.sa_family)
496 return -EAFNOSUPPORT;
497 }
498
499 if (bad_mask(mask, addr))
500 return -EINVAL;
501
502 plen = inet_mask_len(mask);
503 }
504
505 cfg->fc_dst_len = plen;
506 cfg->fc_dst = addr;
507
508 if (cmd != SIOCDELRT) {
509 cfg->fc_nlflags = NLM_F_CREATE;
510 cfg->fc_protocol = RTPROT_BOOT;
511 }
512
513 if (rt->rt_metric)
514 cfg->fc_priority = rt->rt_metric - 1;
515
516 if (rt->rt_flags & RTF_REJECT) {
517 cfg->fc_scope = RT_SCOPE_HOST;
518 cfg->fc_type = RTN_UNREACHABLE;
519 return 0;
520 }
521
522 cfg->fc_scope = RT_SCOPE_NOWHERE;
523 cfg->fc_type = RTN_UNICAST;
524
525 if (rt->rt_dev) {
526 char *colon;
527 struct net_device *dev;
528 char devname[IFNAMSIZ];
529
530 if (copy_from_user(devname, rt->rt_dev, IFNAMSIZ-1))
531 return -EFAULT;
532
533 devname[IFNAMSIZ-1] = 0;
534 colon = strchr(devname, ':');
535 if (colon)
536 *colon = 0;
537 dev = __dev_get_by_name(net, devname);
538 if (!dev)
539 return -ENODEV;
540 cfg->fc_oif = dev->ifindex;
541 cfg->fc_table = l3mdev_fib_table(dev);
542 if (colon) {
543 struct in_ifaddr *ifa;
544 struct in_device *in_dev = __in_dev_get_rtnl(dev);
545 if (!in_dev)
546 return -ENODEV;
547 *colon = ':';
548 for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next)
549 if (strcmp(ifa->ifa_label, devname) == 0)
550 break;
551 if (!ifa)
552 return -ENODEV;
553 cfg->fc_prefsrc = ifa->ifa_local;
554 }
555 }
556
557 addr = sk_extract_addr(&rt->rt_gateway);
558 if (rt->rt_gateway.sa_family == AF_INET && addr) {
559 unsigned int addr_type;
560
561 cfg->fc_gw = addr;
562 addr_type = inet_addr_type_table(net, addr, cfg->fc_table);
563 if (rt->rt_flags & RTF_GATEWAY &&
564 addr_type == RTN_UNICAST)
565 cfg->fc_scope = RT_SCOPE_UNIVERSE;
566 }
567
568 if (cmd == SIOCDELRT)
569 return 0;
570
571 if (rt->rt_flags & RTF_GATEWAY && !cfg->fc_gw)
572 return -EINVAL;
573
574 if (cfg->fc_scope == RT_SCOPE_NOWHERE)
575 cfg->fc_scope = RT_SCOPE_LINK;
576
577 if (rt->rt_flags & (RTF_MTU | RTF_WINDOW | RTF_IRTT)) {
578 struct nlattr *mx;
579 int len = 0;
580
581 mx = kcalloc(3, nla_total_size(4), GFP_KERNEL);
582 if (!mx)
583 return -ENOMEM;
584
585 if (rt->rt_flags & RTF_MTU)
586 len = put_rtax(mx, len, RTAX_ADVMSS, rt->rt_mtu - 40);
587
588 if (rt->rt_flags & RTF_WINDOW)
589 len = put_rtax(mx, len, RTAX_WINDOW, rt->rt_window);
590
591 if (rt->rt_flags & RTF_IRTT)
592 len = put_rtax(mx, len, RTAX_RTT, rt->rt_irtt << 3);
593
594 cfg->fc_mx = mx;
595 cfg->fc_mx_len = len;
596 }
597
598 return 0;
599 }
600
601 /*
602 * Handle IP routing ioctl calls.
603 * These are used to manipulate the routing tables
604 */
605 int ip_rt_ioctl(struct net *net, unsigned int cmd, struct rtentry *rt)
606 {
607 struct fib_config cfg;
608 int err;
609
610 switch (cmd) {
611 case SIOCADDRT: /* Add a route */
612 case SIOCDELRT: /* Delete a route */
613 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
614 return -EPERM;
615
616 rtnl_lock();
617 err = rtentry_to_fib_config(net, cmd, rt, &cfg);
618 if (err == 0) {
619 struct fib_table *tb;
620
621 if (cmd == SIOCDELRT) {
622 tb = fib_get_table(net, cfg.fc_table);
623 if (tb)
624 err = fib_table_delete(net, tb, &cfg,
625 NULL);
626 else
627 err = -ESRCH;
628 } else {
629 tb = fib_new_table(net, cfg.fc_table);
630 if (tb)
631 err = fib_table_insert(net, tb,
632 &cfg, NULL);
633 else
634 err = -ENOBUFS;
635 }
636
637 /* allocated by rtentry_to_fib_config() */
638 kfree(cfg.fc_mx);
639 }
640 rtnl_unlock();
641 return err;
642 }
643 return -EINVAL;
644 }
645
646 const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = {
647 [RTA_DST] = { .type = NLA_U32 },
648 [RTA_SRC] = { .type = NLA_U32 },
649 [RTA_IIF] = { .type = NLA_U32 },
650 [RTA_OIF] = { .type = NLA_U32 },
651 [RTA_GATEWAY] = { .type = NLA_U32 },
652 [RTA_PRIORITY] = { .type = NLA_U32 },
653 [RTA_PREFSRC] = { .type = NLA_U32 },
654 [RTA_METRICS] = { .type = NLA_NESTED },
655 [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
656 [RTA_FLOW] = { .type = NLA_U32 },
657 [RTA_ENCAP_TYPE] = { .type = NLA_U16 },
658 [RTA_ENCAP] = { .type = NLA_NESTED },
659 [RTA_UID] = { .type = NLA_U32 },
660 [RTA_MARK] = { .type = NLA_U32 },
661 [RTA_TABLE] = { .type = NLA_U32 },
662 [RTA_IP_PROTO] = { .type = NLA_U8 },
663 [RTA_SPORT] = { .type = NLA_U16 },
664 [RTA_DPORT] = { .type = NLA_U16 },
665 };
666
667 static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,
668 struct nlmsghdr *nlh, struct fib_config *cfg,
669 struct netlink_ext_ack *extack)
670 {
671 struct nlattr *attr;
672 int err, remaining;
673 struct rtmsg *rtm;
674
675 err = nlmsg_validate(nlh, sizeof(*rtm), RTA_MAX, rtm_ipv4_policy,
676 extack);
677 if (err < 0)
678 goto errout;
679
680 memset(cfg, 0, sizeof(*cfg));
681
682 rtm = nlmsg_data(nlh);
683 cfg->fc_dst_len = rtm->rtm_dst_len;
684 cfg->fc_tos = rtm->rtm_tos;
685 cfg->fc_table = rtm->rtm_table;
686 cfg->fc_protocol = rtm->rtm_protocol;
687 cfg->fc_scope = rtm->rtm_scope;
688 cfg->fc_type = rtm->rtm_type;
689 cfg->fc_flags = rtm->rtm_flags;
690 cfg->fc_nlflags = nlh->nlmsg_flags;
691
692 cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
693 cfg->fc_nlinfo.nlh = nlh;
694 cfg->fc_nlinfo.nl_net = net;
695
696 if (cfg->fc_type > RTN_MAX) {
697 NL_SET_ERR_MSG(extack, "Invalid route type");
698 err = -EINVAL;
699 goto errout;
700 }
701
702 nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), remaining) {
703 switch (nla_type(attr)) {
704 case RTA_DST:
705 cfg->fc_dst = nla_get_be32(attr);
706 break;
707 case RTA_OIF:
708 cfg->fc_oif = nla_get_u32(attr);
709 break;
710 case RTA_GATEWAY:
711 cfg->fc_gw = nla_get_be32(attr);
712 break;
713 case RTA_PRIORITY:
714 cfg->fc_priority = nla_get_u32(attr);
715 break;
716 case RTA_PREFSRC:
717 cfg->fc_prefsrc = nla_get_be32(attr);
718 break;
719 case RTA_METRICS:
720 cfg->fc_mx = nla_data(attr);
721 cfg->fc_mx_len = nla_len(attr);
722 break;
723 case RTA_MULTIPATH:
724 err = lwtunnel_valid_encap_type_attr(nla_data(attr),
725 nla_len(attr),
726 extack);
727 if (err < 0)
728 goto errout;
729 cfg->fc_mp = nla_data(attr);
730 cfg->fc_mp_len = nla_len(attr);
731 break;
732 case RTA_FLOW:
733 cfg->fc_flow = nla_get_u32(attr);
734 break;
735 case RTA_TABLE:
736 cfg->fc_table = nla_get_u32(attr);
737 break;
738 case RTA_ENCAP:
739 cfg->fc_encap = attr;
740 break;
741 case RTA_ENCAP_TYPE:
742 cfg->fc_encap_type = nla_get_u16(attr);
743 err = lwtunnel_valid_encap_type(cfg->fc_encap_type,
744 extack);
745 if (err < 0)
746 goto errout;
747 break;
748 }
749 }
750
751 return 0;
752 errout:
753 return err;
754 }
755
756 static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh,
757 struct netlink_ext_ack *extack)
758 {
759 struct net *net = sock_net(skb->sk);
760 struct fib_config cfg;
761 struct fib_table *tb;
762 int err;
763
764 err = rtm_to_fib_config(net, skb, nlh, &cfg, extack);
765 if (err < 0)
766 goto errout;
767
768 tb = fib_get_table(net, cfg.fc_table);
769 if (!tb) {
770 NL_SET_ERR_MSG(extack, "FIB table does not exist");
771 err = -ESRCH;
772 goto errout;
773 }
774
775 err = fib_table_delete(net, tb, &cfg, extack);
776 errout:
777 return err;
778 }
779
780 static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh,
781 struct netlink_ext_ack *extack)
782 {
783 struct net *net = sock_net(skb->sk);
784 struct fib_config cfg;
785 struct fib_table *tb;
786 int err;
787
788 err = rtm_to_fib_config(net, skb, nlh, &cfg, extack);
789 if (err < 0)
790 goto errout;
791
792 tb = fib_new_table(net, cfg.fc_table);
793 if (!tb) {
794 err = -ENOBUFS;
795 goto errout;
796 }
797
798 err = fib_table_insert(net, tb, &cfg, extack);
799 if (!err && cfg.fc_type == RTN_LOCAL)
800 net->ipv4.fib_has_custom_local_routes = true;
801 errout:
802 return err;
803 }
804
805 int ip_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
806 struct fib_dump_filter *filter,
807 struct netlink_callback *cb)
808 {
809 struct netlink_ext_ack *extack = cb->extack;
810 struct nlattr *tb[RTA_MAX + 1];
811 struct rtmsg *rtm;
812 int err, i;
813
814 ASSERT_RTNL();
815
816 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) {
817 NL_SET_ERR_MSG(extack, "Invalid header for FIB dump request");
818 return -EINVAL;
819 }
820
821 rtm = nlmsg_data(nlh);
822 if (rtm->rtm_dst_len || rtm->rtm_src_len || rtm->rtm_tos ||
823 rtm->rtm_scope) {
824 NL_SET_ERR_MSG(extack, "Invalid values in header for FIB dump request");
825 return -EINVAL;
826 }
827 if (rtm->rtm_flags & ~(RTM_F_CLONED | RTM_F_PREFIX)) {
828 NL_SET_ERR_MSG(extack, "Invalid flags for FIB dump request");
829 return -EINVAL;
830 }
831
832 filter->dump_all_families = (rtm->rtm_family == AF_UNSPEC);
833 filter->flags = rtm->rtm_flags;
834 filter->protocol = rtm->rtm_protocol;
835 filter->rt_type = rtm->rtm_type;
836 filter->table_id = rtm->rtm_table;
837
838 err = nlmsg_parse_strict(nlh, sizeof(*rtm), tb, RTA_MAX,
839 rtm_ipv4_policy, extack);
840 if (err < 0)
841 return err;
842
843 for (i = 0; i <= RTA_MAX; ++i) {
844 int ifindex;
845
846 if (!tb[i])
847 continue;
848
849 switch (i) {
850 case RTA_TABLE:
851 filter->table_id = nla_get_u32(tb[i]);
852 break;
853 case RTA_OIF:
854 ifindex = nla_get_u32(tb[i]);
855 filter->dev = __dev_get_by_index(net, ifindex);
856 if (!filter->dev)
857 return -ENODEV;
858 break;
859 default:
860 NL_SET_ERR_MSG(extack, "Unsupported attribute in dump request");
861 return -EINVAL;
862 }
863 }
864
865 if (filter->flags || filter->protocol || filter->rt_type ||
866 filter->table_id || filter->dev) {
867 filter->filter_set = 1;
868 cb->answer_flags = NLM_F_DUMP_FILTERED;
869 }
870
871 return 0;
872 }
873 EXPORT_SYMBOL_GPL(ip_valid_fib_dump_req);
874
875 static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
876 {
877 const struct nlmsghdr *nlh = cb->nlh;
878 struct net *net = sock_net(skb->sk);
879 struct fib_dump_filter filter = {};
880 unsigned int h, s_h;
881 unsigned int e = 0, s_e;
882 struct fib_table *tb;
883 struct hlist_head *head;
884 int dumped = 0, err;
885
886 if (cb->strict_check) {
887 err = ip_valid_fib_dump_req(net, nlh, &filter, cb);
888 if (err < 0)
889 return err;
890 } else if (nlmsg_len(nlh) >= sizeof(struct rtmsg)) {
891 struct rtmsg *rtm = nlmsg_data(nlh);
892
893 filter.flags = rtm->rtm_flags & (RTM_F_PREFIX | RTM_F_CLONED);
894 }
895
896 /* fib entries are never clones and ipv4 does not use prefix flag */
897 if (filter.flags & (RTM_F_PREFIX | RTM_F_CLONED))
898 return skb->len;
899
900 if (filter.table_id) {
901 tb = fib_get_table(net, filter.table_id);
902 if (!tb) {
903 if (filter.dump_all_families)
904 return skb->len;
905
906 NL_SET_ERR_MSG(cb->extack, "ipv4: FIB table does not exist");
907 return -ENOENT;
908 }
909
910 err = fib_table_dump(tb, skb, cb, &filter);
911 return skb->len ? : err;
912 }
913
914 s_h = cb->args[0];
915 s_e = cb->args[1];
916
917 rcu_read_lock();
918
919 for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) {
920 e = 0;
921 head = &net->ipv4.fib_table_hash[h];
922 hlist_for_each_entry_rcu(tb, head, tb_hlist) {
923 if (e < s_e)
924 goto next;
925 if (dumped)
926 memset(&cb->args[2], 0, sizeof(cb->args) -
927 2 * sizeof(cb->args[0]));
928 err = fib_table_dump(tb, skb, cb, &filter);
929 if (err < 0) {
930 if (likely(skb->len))
931 goto out;
932
933 goto out_err;
934 }
935 dumped = 1;
936 next:
937 e++;
938 }
939 }
940 out:
941 err = skb->len;
942 out_err:
943 rcu_read_unlock();
944
945 cb->args[1] = e;
946 cb->args[0] = h;
947
948 return err;
949 }
950
951 /* Prepare and feed intra-kernel routing request.
952 * Really, it should be netlink message, but :-( netlink
953 * can be not configured, so that we feed it directly
954 * to fib engine. It is legal, because all events occur
955 * only when netlink is already locked.
956 */
957 static void fib_magic(int cmd, int type, __be32 dst, int dst_len,
958 struct in_ifaddr *ifa, u32 rt_priority)
959 {
960 struct net *net = dev_net(ifa->ifa_dev->dev);
961 u32 tb_id = l3mdev_fib_table(ifa->ifa_dev->dev);
962 struct fib_table *tb;
963 struct fib_config cfg = {
964 .fc_protocol = RTPROT_KERNEL,
965 .fc_type = type,
966 .fc_dst = dst,
967 .fc_dst_len = dst_len,
968 .fc_priority = rt_priority,
969 .fc_prefsrc = ifa->ifa_local,
970 .fc_oif = ifa->ifa_dev->dev->ifindex,
971 .fc_nlflags = NLM_F_CREATE | NLM_F_APPEND,
972 .fc_nlinfo = {
973 .nl_net = net,
974 },
975 };
976
977 if (!tb_id)
978 tb_id = (type == RTN_UNICAST) ? RT_TABLE_MAIN : RT_TABLE_LOCAL;
979
980 tb = fib_new_table(net, tb_id);
981 if (!tb)
982 return;
983
984 cfg.fc_table = tb->tb_id;
985
986 if (type != RTN_LOCAL)
987 cfg.fc_scope = RT_SCOPE_LINK;
988 else
989 cfg.fc_scope = RT_SCOPE_HOST;
990
991 if (cmd == RTM_NEWROUTE)
992 fib_table_insert(net, tb, &cfg, NULL);
993 else
994 fib_table_delete(net, tb, &cfg, NULL);
995 }
996
997 void fib_add_ifaddr(struct in_ifaddr *ifa)
998 {
999 struct in_device *in_dev = ifa->ifa_dev;
1000 struct net_device *dev = in_dev->dev;
1001 struct in_ifaddr *prim = ifa;
1002 __be32 mask = ifa->ifa_mask;
1003 __be32 addr = ifa->ifa_local;
1004 __be32 prefix = ifa->ifa_address & mask;
1005
1006 if (ifa->ifa_flags & IFA_F_SECONDARY) {
1007 prim = inet_ifa_byprefix(in_dev, prefix, mask);
1008 if (!prim) {
1009 pr_warn("%s: bug: prim == NULL\n", __func__);
1010 return;
1011 }
1012 }
1013
1014 fib_magic(RTM_NEWROUTE, RTN_LOCAL, addr, 32, prim, 0);
1015
1016 if (!(dev->flags & IFF_UP))
1017 return;
1018
1019 /* Add broadcast address, if it is explicitly assigned. */
1020 if (ifa->ifa_broadcast && ifa->ifa_broadcast != htonl(0xFFFFFFFF))
1021 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32,
1022 prim, 0);
1023
1024 if (!ipv4_is_zeronet(prefix) && !(ifa->ifa_flags & IFA_F_SECONDARY) &&
1025 (prefix != addr || ifa->ifa_prefixlen < 32)) {
1026 if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE))
1027 fib_magic(RTM_NEWROUTE,
1028 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
1029 prefix, ifa->ifa_prefixlen, prim,
1030 ifa->ifa_rt_priority);
1031
1032 /* Add network specific broadcasts, when it takes a sense */
1033 if (ifa->ifa_prefixlen < 31) {
1034 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix, 32,
1035 prim, 0);
1036 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix | ~mask,
1037 32, prim, 0);
1038 }
1039 }
1040 }
1041
1042 void fib_modify_prefix_metric(struct in_ifaddr *ifa, u32 new_metric)
1043 {
1044 __be32 prefix = ifa->ifa_address & ifa->ifa_mask;
1045 struct in_device *in_dev = ifa->ifa_dev;
1046 struct net_device *dev = in_dev->dev;
1047
1048 if (!(dev->flags & IFF_UP) ||
1049 ifa->ifa_flags & (IFA_F_SECONDARY | IFA_F_NOPREFIXROUTE) ||
1050 ipv4_is_zeronet(prefix) ||
1051 prefix == ifa->ifa_local || ifa->ifa_prefixlen == 32)
1052 return;
1053
1054 /* add the new */
1055 fib_magic(RTM_NEWROUTE,
1056 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
1057 prefix, ifa->ifa_prefixlen, ifa, new_metric);
1058
1059 /* delete the old */
1060 fib_magic(RTM_DELROUTE,
1061 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
1062 prefix, ifa->ifa_prefixlen, ifa, ifa->ifa_rt_priority);
1063 }
1064
1065 /* Delete primary or secondary address.
1066 * Optionally, on secondary address promotion consider the addresses
1067 * from subnet iprim as deleted, even if they are in device list.
1068 * In this case the secondary ifa can be in device list.
1069 */
1070 void fib_del_ifaddr(struct in_ifaddr *ifa, struct in_ifaddr *iprim)
1071 {
1072 struct in_device *in_dev = ifa->ifa_dev;
1073 struct net_device *dev = in_dev->dev;
1074 struct in_ifaddr *ifa1;
1075 struct in_ifaddr *prim = ifa, *prim1 = NULL;
1076 __be32 brd = ifa->ifa_address | ~ifa->ifa_mask;
1077 __be32 any = ifa->ifa_address & ifa->ifa_mask;
1078 #define LOCAL_OK 1
1079 #define BRD_OK 2
1080 #define BRD0_OK 4
1081 #define BRD1_OK 8
1082 unsigned int ok = 0;
1083 int subnet = 0; /* Primary network */
1084 int gone = 1; /* Address is missing */
1085 int same_prefsrc = 0; /* Another primary with same IP */
1086
1087 if (ifa->ifa_flags & IFA_F_SECONDARY) {
1088 prim = inet_ifa_byprefix(in_dev, any, ifa->ifa_mask);
1089 if (!prim) {
1090 /* if the device has been deleted, we don't perform
1091 * address promotion
1092 */
1093 if (!in_dev->dead)
1094 pr_warn("%s: bug: prim == NULL\n", __func__);
1095 return;
1096 }
1097 if (iprim && iprim != prim) {
1098 pr_warn("%s: bug: iprim != prim\n", __func__);
1099 return;
1100 }
1101 } else if (!ipv4_is_zeronet(any) &&
1102 (any != ifa->ifa_local || ifa->ifa_prefixlen < 32)) {
1103 if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE))
1104 fib_magic(RTM_DELROUTE,
1105 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
1106 any, ifa->ifa_prefixlen, prim, 0);
1107 subnet = 1;
1108 }
1109
1110 if (in_dev->dead)
1111 goto no_promotions;
1112
1113 /* Deletion is more complicated than add.
1114 * We should take care of not to delete too much :-)
1115 *
1116 * Scan address list to be sure that addresses are really gone.
1117 */
1118
1119 for (ifa1 = in_dev->ifa_list; ifa1; ifa1 = ifa1->ifa_next) {
1120 if (ifa1 == ifa) {
1121 /* promotion, keep the IP */
1122 gone = 0;
1123 continue;
1124 }
1125 /* Ignore IFAs from our subnet */
1126 if (iprim && ifa1->ifa_mask == iprim->ifa_mask &&
1127 inet_ifa_match(ifa1->ifa_address, iprim))
1128 continue;
1129
1130 /* Ignore ifa1 if it uses different primary IP (prefsrc) */
1131 if (ifa1->ifa_flags & IFA_F_SECONDARY) {
1132 /* Another address from our subnet? */
1133 if (ifa1->ifa_mask == prim->ifa_mask &&
1134 inet_ifa_match(ifa1->ifa_address, prim))
1135 prim1 = prim;
1136 else {
1137 /* We reached the secondaries, so
1138 * same_prefsrc should be determined.
1139 */
1140 if (!same_prefsrc)
1141 continue;
1142 /* Search new prim1 if ifa1 is not
1143 * using the current prim1
1144 */
1145 if (!prim1 ||
1146 ifa1->ifa_mask != prim1->ifa_mask ||
1147 !inet_ifa_match(ifa1->ifa_address, prim1))
1148 prim1 = inet_ifa_byprefix(in_dev,
1149 ifa1->ifa_address,
1150 ifa1->ifa_mask);
1151 if (!prim1)
1152 continue;
1153 if (prim1->ifa_local != prim->ifa_local)
1154 continue;
1155 }
1156 } else {
1157 if (prim->ifa_local != ifa1->ifa_local)
1158 continue;
1159 prim1 = ifa1;
1160 if (prim != prim1)
1161 same_prefsrc = 1;
1162 }
1163 if (ifa->ifa_local == ifa1->ifa_local)
1164 ok |= LOCAL_OK;
1165 if (ifa->ifa_broadcast == ifa1->ifa_broadcast)
1166 ok |= BRD_OK;
1167 if (brd == ifa1->ifa_broadcast)
1168 ok |= BRD1_OK;
1169 if (any == ifa1->ifa_broadcast)
1170 ok |= BRD0_OK;
1171 /* primary has network specific broadcasts */
1172 if (prim1 == ifa1 && ifa1->ifa_prefixlen < 31) {
1173 __be32 brd1 = ifa1->ifa_address | ~ifa1->ifa_mask;
1174 __be32 any1 = ifa1->ifa_address & ifa1->ifa_mask;
1175
1176 if (!ipv4_is_zeronet(any1)) {
1177 if (ifa->ifa_broadcast == brd1 ||
1178 ifa->ifa_broadcast == any1)
1179 ok |= BRD_OK;
1180 if (brd == brd1 || brd == any1)
1181 ok |= BRD1_OK;
1182 if (any == brd1 || any == any1)
1183 ok |= BRD0_OK;
1184 }
1185 }
1186 }
1187
1188 no_promotions:
1189 if (!(ok & BRD_OK))
1190 fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32,
1191 prim, 0);
1192 if (subnet && ifa->ifa_prefixlen < 31) {
1193 if (!(ok & BRD1_OK))
1194 fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32,
1195 prim, 0);
1196 if (!(ok & BRD0_OK))
1197 fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32,
1198 prim, 0);
1199 }
1200 if (!(ok & LOCAL_OK)) {
1201 unsigned int addr_type;
1202
1203 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 32, prim, 0);
1204
1205 /* Check, that this local address finally disappeared. */
1206 addr_type = inet_addr_type_dev_table(dev_net(dev), dev,
1207 ifa->ifa_local);
1208 if (gone && addr_type != RTN_LOCAL) {
1209 /* And the last, but not the least thing.
1210 * We must flush stray FIB entries.
1211 *
1212 * First of all, we scan fib_info list searching
1213 * for stray nexthop entries, then ignite fib_flush.
1214 */
1215 if (fib_sync_down_addr(dev, ifa->ifa_local))
1216 fib_flush(dev_net(dev));
1217 }
1218 }
1219 #undef LOCAL_OK
1220 #undef BRD_OK
1221 #undef BRD0_OK
1222 #undef BRD1_OK
1223 }
1224
1225 static void nl_fib_lookup(struct net *net, struct fib_result_nl *frn)
1226 {
1227
1228 struct fib_result res;
1229 struct flowi4 fl4 = {
1230 .flowi4_mark = frn->fl_mark,
1231 .daddr = frn->fl_addr,
1232 .flowi4_tos = frn->fl_tos,
1233 .flowi4_scope = frn->fl_scope,
1234 };
1235 struct fib_table *tb;
1236
1237 rcu_read_lock();
1238
1239 tb = fib_get_table(net, frn->tb_id_in);
1240
1241 frn->err = -ENOENT;
1242 if (tb) {
1243 local_bh_disable();
1244
1245 frn->tb_id = tb->tb_id;
1246 frn->err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF);
1247
1248 if (!frn->err) {
1249 frn->prefixlen = res.prefixlen;
1250 frn->nh_sel = res.nh_sel;
1251 frn->type = res.type;
1252 frn->scope = res.scope;
1253 }
1254 local_bh_enable();
1255 }
1256
1257 rcu_read_unlock();
1258 }
1259
1260 static void nl_fib_input(struct sk_buff *skb)
1261 {
1262 struct net *net;
1263 struct fib_result_nl *frn;
1264 struct nlmsghdr *nlh;
1265 u32 portid;
1266
1267 net = sock_net(skb->sk);
1268 nlh = nlmsg_hdr(skb);
1269 if (skb->len < nlmsg_total_size(sizeof(*frn)) ||
1270 skb->len < nlh->nlmsg_len ||
1271 nlmsg_len(nlh) < sizeof(*frn))
1272 return;
1273
1274 skb = netlink_skb_clone(skb, GFP_KERNEL);
1275 if (!skb)
1276 return;
1277 nlh = nlmsg_hdr(skb);
1278
1279 frn = (struct fib_result_nl *) nlmsg_data(nlh);
1280 nl_fib_lookup(net, frn);
1281
1282 portid = NETLINK_CB(skb).portid; /* netlink portid */
1283 NETLINK_CB(skb).portid = 0; /* from kernel */
1284 NETLINK_CB(skb).dst_group = 0; /* unicast */
1285 netlink_unicast(net->ipv4.fibnl, skb, portid, MSG_DONTWAIT);
1286 }
1287
1288 static int __net_init nl_fib_lookup_init(struct net *net)
1289 {
1290 struct sock *sk;
1291 struct netlink_kernel_cfg cfg = {
1292 .input = nl_fib_input,
1293 };
1294
1295 sk = netlink_kernel_create(net, NETLINK_FIB_LOOKUP, &cfg);
1296 if (!sk)
1297 return -EAFNOSUPPORT;
1298 net->ipv4.fibnl = sk;
1299 return 0;
1300 }
1301
1302 static void nl_fib_lookup_exit(struct net *net)
1303 {
1304 netlink_kernel_release(net->ipv4.fibnl);
1305 net->ipv4.fibnl = NULL;
1306 }
1307
1308 static void fib_disable_ip(struct net_device *dev, unsigned long event,
1309 bool force)
1310 {
1311 if (fib_sync_down_dev(dev, event, force))
1312 fib_flush(dev_net(dev));
1313 else
1314 rt_cache_flush(dev_net(dev));
1315 arp_ifdown(dev);
1316 }
1317
1318 static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
1319 {
1320 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
1321 struct net_device *dev = ifa->ifa_dev->dev;
1322 struct net *net = dev_net(dev);
1323
1324 switch (event) {
1325 case NETDEV_UP:
1326 fib_add_ifaddr(ifa);
1327 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1328 fib_sync_up(dev, RTNH_F_DEAD);
1329 #endif
1330 atomic_inc(&net->ipv4.dev_addr_genid);
1331 rt_cache_flush(dev_net(dev));
1332 break;
1333 case NETDEV_DOWN:
1334 fib_del_ifaddr(ifa, NULL);
1335 atomic_inc(&net->ipv4.dev_addr_genid);
1336 if (!ifa->ifa_dev->ifa_list) {
1337 /* Last address was deleted from this interface.
1338 * Disable IP.
1339 */
1340 fib_disable_ip(dev, event, true);
1341 } else {
1342 rt_cache_flush(dev_net(dev));
1343 }
1344 break;
1345 }
1346 return NOTIFY_DONE;
1347 }
1348
1349 static int fib_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
1350 {
1351 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1352 struct netdev_notifier_changeupper_info *upper_info = ptr;
1353 struct netdev_notifier_info_ext *info_ext = ptr;
1354 struct in_device *in_dev;
1355 struct net *net = dev_net(dev);
1356 unsigned int flags;
1357
1358 if (event == NETDEV_UNREGISTER) {
1359 fib_disable_ip(dev, event, true);
1360 rt_flush_dev(dev);
1361 return NOTIFY_DONE;
1362 }
1363
1364 in_dev = __in_dev_get_rtnl(dev);
1365 if (!in_dev)
1366 return NOTIFY_DONE;
1367
1368 switch (event) {
1369 case NETDEV_UP:
1370 for_ifa(in_dev) {
1371 fib_add_ifaddr(ifa);
1372 } endfor_ifa(in_dev);
1373 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1374 fib_sync_up(dev, RTNH_F_DEAD);
1375 #endif
1376 atomic_inc(&net->ipv4.dev_addr_genid);
1377 rt_cache_flush(net);
1378 break;
1379 case NETDEV_DOWN:
1380 fib_disable_ip(dev, event, false);
1381 break;
1382 case NETDEV_CHANGE:
1383 flags = dev_get_flags(dev);
1384 if (flags & (IFF_RUNNING | IFF_LOWER_UP))
1385 fib_sync_up(dev, RTNH_F_LINKDOWN);
1386 else
1387 fib_sync_down_dev(dev, event, false);
1388 rt_cache_flush(net);
1389 break;
1390 case NETDEV_CHANGEMTU:
1391 fib_sync_mtu(dev, info_ext->ext.mtu);
1392 rt_cache_flush(net);
1393 break;
1394 case NETDEV_CHANGEUPPER:
1395 upper_info = ptr;
1396 /* flush all routes if dev is linked to or unlinked from
1397 * an L3 master device (e.g., VRF)
1398 */
1399 if (upper_info->upper_dev &&
1400 netif_is_l3_master(upper_info->upper_dev))
1401 fib_disable_ip(dev, NETDEV_DOWN, true);
1402 break;
1403 }
1404 return NOTIFY_DONE;
1405 }
1406
1407 static struct notifier_block fib_inetaddr_notifier = {
1408 .notifier_call = fib_inetaddr_event,
1409 };
1410
1411 static struct notifier_block fib_netdev_notifier = {
1412 .notifier_call = fib_netdev_event,
1413 };
1414
1415 static int __net_init ip_fib_net_init(struct net *net)
1416 {
1417 int err;
1418 size_t size = sizeof(struct hlist_head) * FIB_TABLE_HASHSZ;
1419
1420 err = fib4_notifier_init(net);
1421 if (err)
1422 return err;
1423
1424 /* Avoid false sharing : Use at least a full cache line */
1425 size = max_t(size_t, size, L1_CACHE_BYTES);
1426
1427 net->ipv4.fib_table_hash = kzalloc(size, GFP_KERNEL);
1428 if (!net->ipv4.fib_table_hash) {
1429 err = -ENOMEM;
1430 goto err_table_hash_alloc;
1431 }
1432
1433 err = fib4_rules_init(net);
1434 if (err < 0)
1435 goto err_rules_init;
1436 return 0;
1437
1438 err_rules_init:
1439 kfree(net->ipv4.fib_table_hash);
1440 err_table_hash_alloc:
1441 fib4_notifier_exit(net);
1442 return err;
1443 }
1444
1445 static void ip_fib_net_exit(struct net *net)
1446 {
1447 int i;
1448
1449 rtnl_lock();
1450 #ifdef CONFIG_IP_MULTIPLE_TABLES
1451 RCU_INIT_POINTER(net->ipv4.fib_main, NULL);
1452 RCU_INIT_POINTER(net->ipv4.fib_default, NULL);
1453 #endif
1454 /* Destroy the tables in reverse order to guarantee that the
1455 * local table, ID 255, is destroyed before the main table, ID
1456 * 254. This is necessary as the local table may contain
1457 * references to data contained in the main table.
1458 */
1459 for (i = FIB_TABLE_HASHSZ - 1; i >= 0; i--) {
1460 struct hlist_head *head = &net->ipv4.fib_table_hash[i];
1461 struct hlist_node *tmp;
1462 struct fib_table *tb;
1463
1464 hlist_for_each_entry_safe(tb, tmp, head, tb_hlist) {
1465 hlist_del(&tb->tb_hlist);
1466 fib_table_flush(net, tb);
1467 fib_free_table(tb);
1468 }
1469 }
1470
1471 #ifdef CONFIG_IP_MULTIPLE_TABLES
1472 fib4_rules_exit(net);
1473 #endif
1474 rtnl_unlock();
1475 kfree(net->ipv4.fib_table_hash);
1476 fib4_notifier_exit(net);
1477 }
1478
1479 static int __net_init fib_net_init(struct net *net)
1480 {
1481 int error;
1482
1483 #ifdef CONFIG_IP_ROUTE_CLASSID
1484 net->ipv4.fib_num_tclassid_users = 0;
1485 #endif
1486 error = ip_fib_net_init(net);
1487 if (error < 0)
1488 goto out;
1489 error = nl_fib_lookup_init(net);
1490 if (error < 0)
1491 goto out_nlfl;
1492 error = fib_proc_init(net);
1493 if (error < 0)
1494 goto out_proc;
1495 out:
1496 return error;
1497
1498 out_proc:
1499 nl_fib_lookup_exit(net);
1500 out_nlfl:
1501 ip_fib_net_exit(net);
1502 goto out;
1503 }
1504
1505 static void __net_exit fib_net_exit(struct net *net)
1506 {
1507 fib_proc_exit(net);
1508 nl_fib_lookup_exit(net);
1509 ip_fib_net_exit(net);
1510 }
1511
1512 static struct pernet_operations fib_net_ops = {
1513 .init = fib_net_init,
1514 .exit = fib_net_exit,
1515 };
1516
1517 void __init ip_fib_init(void)
1518 {
1519 fib_trie_init();
1520
1521 register_pernet_subsys(&fib_net_ops);
1522
1523 register_netdevice_notifier(&fib_netdev_notifier);
1524 register_inetaddr_notifier(&fib_inetaddr_notifier);
1525
1526 rtnl_register(PF_INET, RTM_NEWROUTE, inet_rtm_newroute, NULL, 0);
1527 rtnl_register(PF_INET, RTM_DELROUTE, inet_rtm_delroute, NULL, 0);
1528 rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib, 0);
1529 }
Linux with added FPC-III support