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16#include <linux/module.h>
17#include <asm/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 <trace/events/fib.h>
50
51#ifndef CONFIG_IP_MULTIPLE_TABLES
52
53static int __net_init fib4_rules_init(struct net *net)
54{
55 struct fib_table *local_table, *main_table;
56
57 main_table = fib_trie_table(RT_TABLE_MAIN, NULL);
58 if (!main_table)
59 return -ENOMEM;
60
61 local_table = fib_trie_table(RT_TABLE_LOCAL, main_table);
62 if (!local_table)
63 goto fail;
64
65 hlist_add_head_rcu(&local_table->tb_hlist,
66 &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX]);
67 hlist_add_head_rcu(&main_table->tb_hlist,
68 &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX]);
69 return 0;
70
71fail:
72 fib_free_table(main_table);
73 return -ENOMEM;
74}
75#else
76
77struct fib_table *fib_new_table(struct net *net, u32 id)
78{
79 struct fib_table *tb, *alias = NULL;
80 unsigned int h;
81
82 if (id == 0)
83 id = RT_TABLE_MAIN;
84 tb = fib_get_table(net, id);
85 if (tb)
86 return tb;
87
88 if (id == RT_TABLE_LOCAL)
89 alias = fib_new_table(net, RT_TABLE_MAIN);
90
91 tb = fib_trie_table(id, alias);
92 if (!tb)
93 return NULL;
94
95 switch (id) {
96 case RT_TABLE_MAIN:
97 rcu_assign_pointer(net->ipv4.fib_main, tb);
98 break;
99 case RT_TABLE_DEFAULT:
100 rcu_assign_pointer(net->ipv4.fib_default, tb);
101 break;
102 default:
103 break;
104 }
105
106 h = id & (FIB_TABLE_HASHSZ - 1);
107 hlist_add_head_rcu(&tb->tb_hlist, &net->ipv4.fib_table_hash[h]);
108 return tb;
109}
110EXPORT_SYMBOL_GPL(fib_new_table);
111
112
113struct fib_table *fib_get_table(struct net *net, u32 id)
114{
115 struct fib_table *tb;
116 struct hlist_head *head;
117 unsigned int h;
118
119 if (id == 0)
120 id = RT_TABLE_MAIN;
121 h = id & (FIB_TABLE_HASHSZ - 1);
122
123 head = &net->ipv4.fib_table_hash[h];
124 hlist_for_each_entry_rcu(tb, head, tb_hlist) {
125 if (tb->tb_id == id)
126 return tb;
127 }
128 return NULL;
129}
130#endif
131
132static void fib_replace_table(struct net *net, struct fib_table *old,
133 struct fib_table *new)
134{
135#ifdef CONFIG_IP_MULTIPLE_TABLES
136 switch (new->tb_id) {
137 case RT_TABLE_MAIN:
138 rcu_assign_pointer(net->ipv4.fib_main, new);
139 break;
140 case RT_TABLE_DEFAULT:
141 rcu_assign_pointer(net->ipv4.fib_default, new);
142 break;
143 default:
144 break;
145 }
146
147#endif
148
149 hlist_replace_rcu(&old->tb_hlist, &new->tb_hlist);
150}
151
152int fib_unmerge(struct net *net)
153{
154 struct fib_table *old, *new, *main_table;
155
156
157 old = fib_get_table(net, RT_TABLE_LOCAL);
158 if (!old)
159 return 0;
160
161 new = fib_trie_unmerge(old);
162 if (!new)
163 return -ENOMEM;
164
165
166 if (new == old)
167 return 0;
168
169
170 fib_replace_table(net, old, new);
171 fib_free_table(old);
172
173
174 main_table = fib_get_table(net, RT_TABLE_MAIN);
175 if (!main_table)
176 return 0;
177
178
179 fib_table_flush_external(main_table);
180
181 return 0;
182}
183
184static void fib_flush(struct net *net)
185{
186 int flushed = 0;
187 unsigned int h;
188
189 for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
190 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
191 struct hlist_node *tmp;
192 struct fib_table *tb;
193
194 hlist_for_each_entry_safe(tb, tmp, head, tb_hlist)
195 flushed += fib_table_flush(net, tb);
196 }
197
198 if (flushed)
199 rt_cache_flush(net);
200}
201
202
203
204
205
206static inline unsigned int __inet_dev_addr_type(struct net *net,
207 const struct net_device *dev,
208 __be32 addr, u32 tb_id)
209{
210 struct flowi4 fl4 = { .daddr = addr };
211 struct fib_result res;
212 unsigned int ret = RTN_BROADCAST;
213 struct fib_table *table;
214
215 if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr))
216 return RTN_BROADCAST;
217 if (ipv4_is_multicast(addr))
218 return RTN_MULTICAST;
219
220 rcu_read_lock();
221
222 table = fib_get_table(net, tb_id);
223 if (table) {
224 ret = RTN_UNICAST;
225 if (!fib_table_lookup(table, &fl4, &res, FIB_LOOKUP_NOREF)) {
226 if (!dev || dev == res.fi->fib_dev)
227 ret = res.type;
228 }
229 }
230
231 rcu_read_unlock();
232 return ret;
233}
234
235unsigned int inet_addr_type_table(struct net *net, __be32 addr, u32 tb_id)
236{
237 return __inet_dev_addr_type(net, NULL, addr, tb_id);
238}
239EXPORT_SYMBOL(inet_addr_type_table);
240
241unsigned int inet_addr_type(struct net *net, __be32 addr)
242{
243 return __inet_dev_addr_type(net, NULL, addr, RT_TABLE_LOCAL);
244}
245EXPORT_SYMBOL(inet_addr_type);
246
247unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev,
248 __be32 addr)
249{
250 u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL;
251
252 return __inet_dev_addr_type(net, dev, addr, rt_table);
253}
254EXPORT_SYMBOL(inet_dev_addr_type);
255
256
257
258
259unsigned int inet_addr_type_dev_table(struct net *net,
260 const struct net_device *dev,
261 __be32 addr)
262{
263 u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL;
264
265 return __inet_dev_addr_type(net, NULL, addr, rt_table);
266}
267EXPORT_SYMBOL(inet_addr_type_dev_table);
268
269__be32 fib_compute_spec_dst(struct sk_buff *skb)
270{
271 struct net_device *dev = skb->dev;
272 struct in_device *in_dev;
273 struct fib_result res;
274 struct rtable *rt;
275 struct net *net;
276 int scope;
277
278 rt = skb_rtable(skb);
279 if ((rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST | RTCF_LOCAL)) ==
280 RTCF_LOCAL)
281 return ip_hdr(skb)->daddr;
282
283 in_dev = __in_dev_get_rcu(dev);
284 BUG_ON(!in_dev);
285
286 net = dev_net(dev);
287
288 scope = RT_SCOPE_UNIVERSE;
289 if (!ipv4_is_zeronet(ip_hdr(skb)->saddr)) {
290 struct flowi4 fl4 = {
291 .flowi4_iif = LOOPBACK_IFINDEX,
292 .daddr = ip_hdr(skb)->saddr,
293 .flowi4_tos = RT_TOS(ip_hdr(skb)->tos),
294 .flowi4_scope = scope,
295 .flowi4_mark = IN_DEV_SRC_VMARK(in_dev) ? skb->mark : 0,
296 };
297 if (!fib_lookup(net, &fl4, &res, 0))
298 return FIB_RES_PREFSRC(net, res);
299 } else {
300 scope = RT_SCOPE_LINK;
301 }
302
303 return inet_select_addr(dev, ip_hdr(skb)->saddr, scope);
304}
305
306
307
308
309
310
311
312
313
314static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
315 u8 tos, int oif, struct net_device *dev,
316 int rpf, struct in_device *idev, u32 *itag)
317{
318 int ret, no_addr;
319 struct fib_result res;
320 struct flowi4 fl4;
321 struct net *net;
322 bool dev_match;
323
324 fl4.flowi4_oif = 0;
325 fl4.flowi4_iif = l3mdev_master_ifindex_rcu(dev);
326 if (!fl4.flowi4_iif)
327 fl4.flowi4_iif = oif ? : LOOPBACK_IFINDEX;
328 fl4.daddr = src;
329 fl4.saddr = dst;
330 fl4.flowi4_tos = tos;
331 fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
332 fl4.flowi4_tun_key.tun_id = 0;
333 fl4.flowi4_flags = 0;
334
335 no_addr = idev->ifa_list == NULL;
336
337 fl4.flowi4_mark = IN_DEV_SRC_VMARK(idev) ? skb->mark : 0;
338
339 trace_fib_validate_source(dev, &fl4);
340
341 net = dev_net(dev);
342 if (fib_lookup(net, &fl4, &res, 0))
343 goto last_resort;
344 if (res.type != RTN_UNICAST &&
345 (res.type != RTN_LOCAL || !IN_DEV_ACCEPT_LOCAL(idev)))
346 goto e_inval;
347 if (!rpf && !fib_num_tclassid_users(dev_net(dev)) &&
348 (dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev)))
349 goto last_resort;
350 fib_combine_itag(itag, &res);
351 dev_match = false;
352
353#ifdef CONFIG_IP_ROUTE_MULTIPATH
354 for (ret = 0; ret < res.fi->fib_nhs; ret++) {
355 struct fib_nh *nh = &res.fi->fib_nh[ret];
356
357 if (nh->nh_dev == dev) {
358 dev_match = true;
359 break;
360 } else if (l3mdev_master_ifindex_rcu(nh->nh_dev) == dev->ifindex) {
361 dev_match = true;
362 break;
363 }
364 }
365#else
366 if (FIB_RES_DEV(res) == dev)
367 dev_match = true;
368#endif
369 if (dev_match) {
370 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
371 return ret;
372 }
373 if (no_addr)
374 goto last_resort;
375 if (rpf == 1)
376 goto e_rpf;
377 fl4.flowi4_oif = dev->ifindex;
378
379 ret = 0;
380 if (fib_lookup(net, &fl4, &res, FIB_LOOKUP_IGNORE_LINKSTATE) == 0) {
381 if (res.type == RTN_UNICAST)
382 ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
383 }
384 return ret;
385
386last_resort:
387 if (rpf)
388 goto e_rpf;
389 *itag = 0;
390 return 0;
391
392e_inval:
393 return -EINVAL;
394e_rpf:
395 return -EXDEV;
396}
397
398
399int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
400 u8 tos, int oif, struct net_device *dev,
401 struct in_device *idev, u32 *itag)
402{
403 int r = secpath_exists(skb) ? 0 : IN_DEV_RPFILTER(idev);
404
405 if (!r && !fib_num_tclassid_users(dev_net(dev)) &&
406 IN_DEV_ACCEPT_LOCAL(idev) &&
407 (dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev))) {
408 *itag = 0;
409 return 0;
410 }
411 return __fib_validate_source(skb, src, dst, tos, oif, dev, r, idev, itag);
412}
413
414static inline __be32 sk_extract_addr(struct sockaddr *addr)
415{
416 return ((struct sockaddr_in *) addr)->sin_addr.s_addr;
417}
418
419static int put_rtax(struct nlattr *mx, int len, int type, u32 value)
420{
421 struct nlattr *nla;
422
423 nla = (struct nlattr *) ((char *) mx + len);
424 nla->nla_type = type;
425 nla->nla_len = nla_attr_size(4);
426 *(u32 *) nla_data(nla) = value;
427
428 return len + nla_total_size(4);
429}
430
431static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt,
432 struct fib_config *cfg)
433{
434 __be32 addr;
435 int plen;
436
437 memset(cfg, 0, sizeof(*cfg));
438 cfg->fc_nlinfo.nl_net = net;
439
440 if (rt->rt_dst.sa_family != AF_INET)
441 return -EAFNOSUPPORT;
442
443
444
445
446
447
448
449
450
451 plen = 32;
452 addr = sk_extract_addr(&rt->rt_dst);
453 if (!(rt->rt_flags & RTF_HOST)) {
454 __be32 mask = sk_extract_addr(&rt->rt_genmask);
455
456 if (rt->rt_genmask.sa_family != AF_INET) {
457 if (mask || rt->rt_genmask.sa_family)
458 return -EAFNOSUPPORT;
459 }
460
461 if (bad_mask(mask, addr))
462 return -EINVAL;
463
464 plen = inet_mask_len(mask);
465 }
466
467 cfg->fc_dst_len = plen;
468 cfg->fc_dst = addr;
469
470 if (cmd != SIOCDELRT) {
471 cfg->fc_nlflags = NLM_F_CREATE;
472 cfg->fc_protocol = RTPROT_BOOT;
473 }
474
475 if (rt->rt_metric)
476 cfg->fc_priority = rt->rt_metric - 1;
477
478 if (rt->rt_flags & RTF_REJECT) {
479 cfg->fc_scope = RT_SCOPE_HOST;
480 cfg->fc_type = RTN_UNREACHABLE;
481 return 0;
482 }
483
484 cfg->fc_scope = RT_SCOPE_NOWHERE;
485 cfg->fc_type = RTN_UNICAST;
486
487 if (rt->rt_dev) {
488 char *colon;
489 struct net_device *dev;
490 char devname[IFNAMSIZ];
491
492 if (copy_from_user(devname, rt->rt_dev, IFNAMSIZ-1))
493 return -EFAULT;
494
495 devname[IFNAMSIZ-1] = 0;
496 colon = strchr(devname, ':');
497 if (colon)
498 *colon = 0;
499 dev = __dev_get_by_name(net, devname);
500 if (!dev)
501 return -ENODEV;
502 cfg->fc_oif = dev->ifindex;
503 cfg->fc_table = l3mdev_fib_table(dev);
504 if (colon) {
505 struct in_ifaddr *ifa;
506 struct in_device *in_dev = __in_dev_get_rtnl(dev);
507 if (!in_dev)
508 return -ENODEV;
509 *colon = ':';
510 for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next)
511 if (strcmp(ifa->ifa_label, devname) == 0)
512 break;
513 if (!ifa)
514 return -ENODEV;
515 cfg->fc_prefsrc = ifa->ifa_local;
516 }
517 }
518
519 addr = sk_extract_addr(&rt->rt_gateway);
520 if (rt->rt_gateway.sa_family == AF_INET && addr) {
521 unsigned int addr_type;
522
523 cfg->fc_gw = addr;
524 addr_type = inet_addr_type_table(net, addr, cfg->fc_table);
525 if (rt->rt_flags & RTF_GATEWAY &&
526 addr_type == RTN_UNICAST)
527 cfg->fc_scope = RT_SCOPE_UNIVERSE;
528 }
529
530 if (cmd == SIOCDELRT)
531 return 0;
532
533 if (rt->rt_flags & RTF_GATEWAY && !cfg->fc_gw)
534 return -EINVAL;
535
536 if (cfg->fc_scope == RT_SCOPE_NOWHERE)
537 cfg->fc_scope = RT_SCOPE_LINK;
538
539 if (rt->rt_flags & (RTF_MTU | RTF_WINDOW | RTF_IRTT)) {
540 struct nlattr *mx;
541 int len = 0;
542
543 mx = kzalloc(3 * nla_total_size(4), GFP_KERNEL);
544 if (!mx)
545 return -ENOMEM;
546
547 if (rt->rt_flags & RTF_MTU)
548 len = put_rtax(mx, len, RTAX_ADVMSS, rt->rt_mtu - 40);
549
550 if (rt->rt_flags & RTF_WINDOW)
551 len = put_rtax(mx, len, RTAX_WINDOW, rt->rt_window);
552
553 if (rt->rt_flags & RTF_IRTT)
554 len = put_rtax(mx, len, RTAX_RTT, rt->rt_irtt << 3);
555
556 cfg->fc_mx = mx;
557 cfg->fc_mx_len = len;
558 }
559
560 return 0;
561}
562
563
564
565
566
567int ip_rt_ioctl(struct net *net, unsigned int cmd, void __user *arg)
568{
569 struct fib_config cfg;
570 struct rtentry rt;
571 int err;
572
573 switch (cmd) {
574 case SIOCADDRT:
575 case SIOCDELRT:
576 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
577 return -EPERM;
578
579 if (copy_from_user(&rt, arg, sizeof(rt)))
580 return -EFAULT;
581
582 rtnl_lock();
583 err = rtentry_to_fib_config(net, cmd, &rt, &cfg);
584 if (err == 0) {
585 struct fib_table *tb;
586
587 if (cmd == SIOCDELRT) {
588 tb = fib_get_table(net, cfg.fc_table);
589 if (tb)
590 err = fib_table_delete(net, tb, &cfg);
591 else
592 err = -ESRCH;
593 } else {
594 tb = fib_new_table(net, cfg.fc_table);
595 if (tb)
596 err = fib_table_insert(net, tb, &cfg);
597 else
598 err = -ENOBUFS;
599 }
600
601
602 kfree(cfg.fc_mx);
603 }
604 rtnl_unlock();
605 return err;
606 }
607 return -EINVAL;
608}
609
610const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = {
611 [RTA_DST] = { .type = NLA_U32 },
612 [RTA_SRC] = { .type = NLA_U32 },
613 [RTA_IIF] = { .type = NLA_U32 },
614 [RTA_OIF] = { .type = NLA_U32 },
615 [RTA_GATEWAY] = { .type = NLA_U32 },
616 [RTA_PRIORITY] = { .type = NLA_U32 },
617 [RTA_PREFSRC] = { .type = NLA_U32 },
618 [RTA_METRICS] = { .type = NLA_NESTED },
619 [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) },
620 [RTA_FLOW] = { .type = NLA_U32 },
621 [RTA_ENCAP_TYPE] = { .type = NLA_U16 },
622 [RTA_ENCAP] = { .type = NLA_NESTED },
623};
624
625static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,
626 struct nlmsghdr *nlh, struct fib_config *cfg)
627{
628 struct nlattr *attr;
629 int err, remaining;
630 struct rtmsg *rtm;
631
632 err = nlmsg_validate(nlh, sizeof(*rtm), RTA_MAX, rtm_ipv4_policy);
633 if (err < 0)
634 goto errout;
635
636 memset(cfg, 0, sizeof(*cfg));
637
638 rtm = nlmsg_data(nlh);
639 cfg->fc_dst_len = rtm->rtm_dst_len;
640 cfg->fc_tos = rtm->rtm_tos;
641 cfg->fc_table = rtm->rtm_table;
642 cfg->fc_protocol = rtm->rtm_protocol;
643 cfg->fc_scope = rtm->rtm_scope;
644 cfg->fc_type = rtm->rtm_type;
645 cfg->fc_flags = rtm->rtm_flags;
646 cfg->fc_nlflags = nlh->nlmsg_flags;
647
648 cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
649 cfg->fc_nlinfo.nlh = nlh;
650 cfg->fc_nlinfo.nl_net = net;
651
652 if (cfg->fc_type > RTN_MAX) {
653 err = -EINVAL;
654 goto errout;
655 }
656
657 nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), remaining) {
658 switch (nla_type(attr)) {
659 case RTA_DST:
660 cfg->fc_dst = nla_get_be32(attr);
661 break;
662 case RTA_OIF:
663 cfg->fc_oif = nla_get_u32(attr);
664 break;
665 case RTA_GATEWAY:
666 cfg->fc_gw = nla_get_be32(attr);
667 break;
668 case RTA_PRIORITY:
669 cfg->fc_priority = nla_get_u32(attr);
670 break;
671 case RTA_PREFSRC:
672 cfg->fc_prefsrc = nla_get_be32(attr);
673 break;
674 case RTA_METRICS:
675 cfg->fc_mx = nla_data(attr);
676 cfg->fc_mx_len = nla_len(attr);
677 break;
678 case RTA_MULTIPATH:
679 cfg->fc_mp = nla_data(attr);
680 cfg->fc_mp_len = nla_len(attr);
681 break;
682 case RTA_FLOW:
683 cfg->fc_flow = nla_get_u32(attr);
684 break;
685 case RTA_TABLE:
686 cfg->fc_table = nla_get_u32(attr);
687 break;
688 case RTA_ENCAP:
689 cfg->fc_encap = attr;
690 break;
691 case RTA_ENCAP_TYPE:
692 cfg->fc_encap_type = nla_get_u16(attr);
693 break;
694 }
695 }
696
697 return 0;
698errout:
699 return err;
700}
701
702static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
703{
704 struct net *net = sock_net(skb->sk);
705 struct fib_config cfg;
706 struct fib_table *tb;
707 int err;
708
709 err = rtm_to_fib_config(net, skb, nlh, &cfg);
710 if (err < 0)
711 goto errout;
712
713 tb = fib_get_table(net, cfg.fc_table);
714 if (!tb) {
715 err = -ESRCH;
716 goto errout;
717 }
718
719 err = fib_table_delete(net, tb, &cfg);
720errout:
721 return err;
722}
723
724static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
725{
726 struct net *net = sock_net(skb->sk);
727 struct fib_config cfg;
728 struct fib_table *tb;
729 int err;
730
731 err = rtm_to_fib_config(net, skb, nlh, &cfg);
732 if (err < 0)
733 goto errout;
734
735 tb = fib_new_table(net, cfg.fc_table);
736 if (!tb) {
737 err = -ENOBUFS;
738 goto errout;
739 }
740
741 err = fib_table_insert(net, tb, &cfg);
742errout:
743 return err;
744}
745
746static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
747{
748 struct net *net = sock_net(skb->sk);
749 unsigned int h, s_h;
750 unsigned int e = 0, s_e;
751 struct fib_table *tb;
752 struct hlist_head *head;
753 int dumped = 0;
754
755 if (nlmsg_len(cb->nlh) >= sizeof(struct rtmsg) &&
756 ((struct rtmsg *) nlmsg_data(cb->nlh))->rtm_flags & RTM_F_CLONED)
757 return skb->len;
758
759 s_h = cb->args[0];
760 s_e = cb->args[1];
761
762 rcu_read_lock();
763
764 for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) {
765 e = 0;
766 head = &net->ipv4.fib_table_hash[h];
767 hlist_for_each_entry_rcu(tb, head, tb_hlist) {
768 if (e < s_e)
769 goto next;
770 if (dumped)
771 memset(&cb->args[2], 0, sizeof(cb->args) -
772 2 * sizeof(cb->args[0]));
773 if (fib_table_dump(tb, skb, cb) < 0)
774 goto out;
775 dumped = 1;
776next:
777 e++;
778 }
779 }
780out:
781 rcu_read_unlock();
782
783 cb->args[1] = e;
784 cb->args[0] = h;
785
786 return skb->len;
787}
788
789
790
791
792
793
794
795static void fib_magic(int cmd, int type, __be32 dst, int dst_len, struct in_ifaddr *ifa)
796{
797 struct net *net = dev_net(ifa->ifa_dev->dev);
798 u32 tb_id = l3mdev_fib_table(ifa->ifa_dev->dev);
799 struct fib_table *tb;
800 struct fib_config cfg = {
801 .fc_protocol = RTPROT_KERNEL,
802 .fc_type = type,
803 .fc_dst = dst,
804 .fc_dst_len = dst_len,
805 .fc_prefsrc = ifa->ifa_local,
806 .fc_oif = ifa->ifa_dev->dev->ifindex,
807 .fc_nlflags = NLM_F_CREATE | NLM_F_APPEND,
808 .fc_nlinfo = {
809 .nl_net = net,
810 },
811 };
812
813 if (!tb_id)
814 tb_id = (type == RTN_UNICAST) ? RT_TABLE_MAIN : RT_TABLE_LOCAL;
815
816 tb = fib_new_table(net, tb_id);
817 if (!tb)
818 return;
819
820 cfg.fc_table = tb->tb_id;
821
822 if (type != RTN_LOCAL)
823 cfg.fc_scope = RT_SCOPE_LINK;
824 else
825 cfg.fc_scope = RT_SCOPE_HOST;
826
827 if (cmd == RTM_NEWROUTE)
828 fib_table_insert(net, tb, &cfg);
829 else
830 fib_table_delete(net, tb, &cfg);
831}
832
833void fib_add_ifaddr(struct in_ifaddr *ifa)
834{
835 struct in_device *in_dev = ifa->ifa_dev;
836 struct net_device *dev = in_dev->dev;
837 struct in_ifaddr *prim = ifa;
838 __be32 mask = ifa->ifa_mask;
839 __be32 addr = ifa->ifa_local;
840 __be32 prefix = ifa->ifa_address & mask;
841
842 if (ifa->ifa_flags & IFA_F_SECONDARY) {
843 prim = inet_ifa_byprefix(in_dev, prefix, mask);
844 if (!prim) {
845 pr_warn("%s: bug: prim == NULL\n", __func__);
846 return;
847 }
848 }
849
850 fib_magic(RTM_NEWROUTE, RTN_LOCAL, addr, 32, prim);
851
852 if (!(dev->flags & IFF_UP))
853 return;
854
855
856 if (ifa->ifa_broadcast && ifa->ifa_broadcast != htonl(0xFFFFFFFF))
857 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim);
858
859 if (!ipv4_is_zeronet(prefix) && !(ifa->ifa_flags & IFA_F_SECONDARY) &&
860 (prefix != addr || ifa->ifa_prefixlen < 32)) {
861 if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE))
862 fib_magic(RTM_NEWROUTE,
863 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
864 prefix, ifa->ifa_prefixlen, prim);
865
866
867 if (ifa->ifa_prefixlen < 31) {
868 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix, 32, prim);
869 fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix | ~mask,
870 32, prim);
871 }
872 }
873}
874
875
876
877
878
879
880void fib_del_ifaddr(struct in_ifaddr *ifa, struct in_ifaddr *iprim)
881{
882 struct in_device *in_dev = ifa->ifa_dev;
883 struct net_device *dev = in_dev->dev;
884 struct in_ifaddr *ifa1;
885 struct in_ifaddr *prim = ifa, *prim1 = NULL;
886 __be32 brd = ifa->ifa_address | ~ifa->ifa_mask;
887 __be32 any = ifa->ifa_address & ifa->ifa_mask;
888#define LOCAL_OK 1
889#define BRD_OK 2
890#define BRD0_OK 4
891#define BRD1_OK 8
892 unsigned int ok = 0;
893 int subnet = 0;
894 int gone = 1;
895 int same_prefsrc = 0;
896
897 if (ifa->ifa_flags & IFA_F_SECONDARY) {
898 prim = inet_ifa_byprefix(in_dev, any, ifa->ifa_mask);
899 if (!prim) {
900
901
902
903 if (!in_dev->dead)
904 pr_warn("%s: bug: prim == NULL\n", __func__);
905 return;
906 }
907 if (iprim && iprim != prim) {
908 pr_warn("%s: bug: iprim != prim\n", __func__);
909 return;
910 }
911 } else if (!ipv4_is_zeronet(any) &&
912 (any != ifa->ifa_local || ifa->ifa_prefixlen < 32)) {
913 if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE))
914 fib_magic(RTM_DELROUTE,
915 dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
916 any, ifa->ifa_prefixlen, prim);
917 subnet = 1;
918 }
919
920 if (in_dev->dead)
921 goto no_promotions;
922
923
924
925
926
927
928
929 for (ifa1 = in_dev->ifa_list; ifa1; ifa1 = ifa1->ifa_next) {
930 if (ifa1 == ifa) {
931
932 gone = 0;
933 continue;
934 }
935
936 if (iprim && ifa1->ifa_mask == iprim->ifa_mask &&
937 inet_ifa_match(ifa1->ifa_address, iprim))
938 continue;
939
940
941 if (ifa1->ifa_flags & IFA_F_SECONDARY) {
942
943 if (ifa1->ifa_mask == prim->ifa_mask &&
944 inet_ifa_match(ifa1->ifa_address, prim))
945 prim1 = prim;
946 else {
947
948
949
950 if (!same_prefsrc)
951 continue;
952
953
954
955 if (!prim1 ||
956 ifa1->ifa_mask != prim1->ifa_mask ||
957 !inet_ifa_match(ifa1->ifa_address, prim1))
958 prim1 = inet_ifa_byprefix(in_dev,
959 ifa1->ifa_address,
960 ifa1->ifa_mask);
961 if (!prim1)
962 continue;
963 if (prim1->ifa_local != prim->ifa_local)
964 continue;
965 }
966 } else {
967 if (prim->ifa_local != ifa1->ifa_local)
968 continue;
969 prim1 = ifa1;
970 if (prim != prim1)
971 same_prefsrc = 1;
972 }
973 if (ifa->ifa_local == ifa1->ifa_local)
974 ok |= LOCAL_OK;
975 if (ifa->ifa_broadcast == ifa1->ifa_broadcast)
976 ok |= BRD_OK;
977 if (brd == ifa1->ifa_broadcast)
978 ok |= BRD1_OK;
979 if (any == ifa1->ifa_broadcast)
980 ok |= BRD0_OK;
981
982 if (prim1 == ifa1 && ifa1->ifa_prefixlen < 31) {
983 __be32 brd1 = ifa1->ifa_address | ~ifa1->ifa_mask;
984 __be32 any1 = ifa1->ifa_address & ifa1->ifa_mask;
985
986 if (!ipv4_is_zeronet(any1)) {
987 if (ifa->ifa_broadcast == brd1 ||
988 ifa->ifa_broadcast == any1)
989 ok |= BRD_OK;
990 if (brd == brd1 || brd == any1)
991 ok |= BRD1_OK;
992 if (any == brd1 || any == any1)
993 ok |= BRD0_OK;
994 }
995 }
996 }
997
998no_promotions:
999 if (!(ok & BRD_OK))
1000 fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim);
1001 if (subnet && ifa->ifa_prefixlen < 31) {
1002 if (!(ok & BRD1_OK))
1003 fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32, prim);
1004 if (!(ok & BRD0_OK))
1005 fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32, prim);
1006 }
1007 if (!(ok & LOCAL_OK)) {
1008 unsigned int addr_type;
1009
1010 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 32, prim);
1011
1012
1013 addr_type = inet_addr_type_dev_table(dev_net(dev), dev,
1014 ifa->ifa_local);
1015 if (gone && addr_type != RTN_LOCAL) {
1016
1017
1018
1019
1020
1021
1022 if (fib_sync_down_addr(dev, ifa->ifa_local))
1023 fib_flush(dev_net(dev));
1024 }
1025 }
1026#undef LOCAL_OK
1027#undef BRD_OK
1028#undef BRD0_OK
1029#undef BRD1_OK
1030}
1031
1032static void nl_fib_lookup(struct net *net, struct fib_result_nl *frn)
1033{
1034
1035 struct fib_result res;
1036 struct flowi4 fl4 = {
1037 .flowi4_mark = frn->fl_mark,
1038 .daddr = frn->fl_addr,
1039 .flowi4_tos = frn->fl_tos,
1040 .flowi4_scope = frn->fl_scope,
1041 };
1042 struct fib_table *tb;
1043
1044 rcu_read_lock();
1045
1046 tb = fib_get_table(net, frn->tb_id_in);
1047
1048 frn->err = -ENOENT;
1049 if (tb) {
1050 local_bh_disable();
1051
1052 frn->tb_id = tb->tb_id;
1053 frn->err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF);
1054
1055 if (!frn->err) {
1056 frn->prefixlen = res.prefixlen;
1057 frn->nh_sel = res.nh_sel;
1058 frn->type = res.type;
1059 frn->scope = res.scope;
1060 }
1061 local_bh_enable();
1062 }
1063
1064 rcu_read_unlock();
1065}
1066
1067static void nl_fib_input(struct sk_buff *skb)
1068{
1069 struct net *net;
1070 struct fib_result_nl *frn;
1071 struct nlmsghdr *nlh;
1072 u32 portid;
1073
1074 net = sock_net(skb->sk);
1075 nlh = nlmsg_hdr(skb);
1076 if (skb->len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len ||
1077 nlmsg_len(nlh) < sizeof(*frn))
1078 return;
1079
1080 skb = netlink_skb_clone(skb, GFP_KERNEL);
1081 if (!skb)
1082 return;
1083 nlh = nlmsg_hdr(skb);
1084
1085 frn = (struct fib_result_nl *) nlmsg_data(nlh);
1086 nl_fib_lookup(net, frn);
1087
1088 portid = NETLINK_CB(skb).portid;
1089 NETLINK_CB(skb).portid = 0;
1090 NETLINK_CB(skb).dst_group = 0;
1091 netlink_unicast(net->ipv4.fibnl, skb, portid, MSG_DONTWAIT);
1092}
1093
1094static int __net_init nl_fib_lookup_init(struct net *net)
1095{
1096 struct sock *sk;
1097 struct netlink_kernel_cfg cfg = {
1098 .input = nl_fib_input,
1099 };
1100
1101 sk = netlink_kernel_create(net, NETLINK_FIB_LOOKUP, &cfg);
1102 if (!sk)
1103 return -EAFNOSUPPORT;
1104 net->ipv4.fibnl = sk;
1105 return 0;
1106}
1107
1108static void nl_fib_lookup_exit(struct net *net)
1109{
1110 netlink_kernel_release(net->ipv4.fibnl);
1111 net->ipv4.fibnl = NULL;
1112}
1113
1114static void fib_disable_ip(struct net_device *dev, unsigned long event,
1115 bool force)
1116{
1117 if (fib_sync_down_dev(dev, event, force))
1118 fib_flush(dev_net(dev));
1119 rt_cache_flush(dev_net(dev));
1120 arp_ifdown(dev);
1121}
1122
1123static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
1124{
1125 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
1126 struct net_device *dev = ifa->ifa_dev->dev;
1127 struct net *net = dev_net(dev);
1128
1129 switch (event) {
1130 case NETDEV_UP:
1131 fib_add_ifaddr(ifa);
1132#ifdef CONFIG_IP_ROUTE_MULTIPATH
1133 fib_sync_up(dev, RTNH_F_DEAD);
1134#endif
1135 atomic_inc(&net->ipv4.dev_addr_genid);
1136 rt_cache_flush(dev_net(dev));
1137 break;
1138 case NETDEV_DOWN:
1139 fib_del_ifaddr(ifa, NULL);
1140 atomic_inc(&net->ipv4.dev_addr_genid);
1141 if (!ifa->ifa_dev->ifa_list) {
1142
1143
1144
1145 fib_disable_ip(dev, event, true);
1146 } else {
1147 rt_cache_flush(dev_net(dev));
1148 }
1149 break;
1150 }
1151 return NOTIFY_DONE;
1152}
1153
1154static int fib_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
1155{
1156 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1157 struct netdev_notifier_changeupper_info *info;
1158 struct in_device *in_dev;
1159 struct net *net = dev_net(dev);
1160 unsigned int flags;
1161
1162 if (event == NETDEV_UNREGISTER) {
1163 fib_disable_ip(dev, event, true);
1164 rt_flush_dev(dev);
1165 return NOTIFY_DONE;
1166 }
1167
1168 in_dev = __in_dev_get_rtnl(dev);
1169 if (!in_dev)
1170 return NOTIFY_DONE;
1171
1172 switch (event) {
1173 case NETDEV_UP:
1174 for_ifa(in_dev) {
1175 fib_add_ifaddr(ifa);
1176 } endfor_ifa(in_dev);
1177#ifdef CONFIG_IP_ROUTE_MULTIPATH
1178 fib_sync_up(dev, RTNH_F_DEAD);
1179#endif
1180 atomic_inc(&net->ipv4.dev_addr_genid);
1181 rt_cache_flush(net);
1182 break;
1183 case NETDEV_DOWN:
1184 fib_disable_ip(dev, event, false);
1185 break;
1186 case NETDEV_CHANGE:
1187 flags = dev_get_flags(dev);
1188 if (flags & (IFF_RUNNING | IFF_LOWER_UP))
1189 fib_sync_up(dev, RTNH_F_LINKDOWN);
1190 else
1191 fib_sync_down_dev(dev, event, false);
1192
1193 case NETDEV_CHANGEMTU:
1194 rt_cache_flush(net);
1195 break;
1196 case NETDEV_CHANGEUPPER:
1197 info = ptr;
1198
1199
1200
1201 if (info->upper_dev && netif_is_l3_master(info->upper_dev))
1202 fib_disable_ip(dev, NETDEV_DOWN, true);
1203 break;
1204 }
1205 return NOTIFY_DONE;
1206}
1207
1208static struct notifier_block fib_inetaddr_notifier = {
1209 .notifier_call = fib_inetaddr_event,
1210};
1211
1212static struct notifier_block fib_netdev_notifier = {
1213 .notifier_call = fib_netdev_event,
1214};
1215
1216static int __net_init ip_fib_net_init(struct net *net)
1217{
1218 int err;
1219 size_t size = sizeof(struct hlist_head) * FIB_TABLE_HASHSZ;
1220
1221
1222 size = max_t(size_t, size, L1_CACHE_BYTES);
1223
1224 net->ipv4.fib_table_hash = kzalloc(size, GFP_KERNEL);
1225 if (!net->ipv4.fib_table_hash)
1226 return -ENOMEM;
1227
1228 err = fib4_rules_init(net);
1229 if (err < 0)
1230 goto fail;
1231 return 0;
1232
1233fail:
1234 kfree(net->ipv4.fib_table_hash);
1235 return err;
1236}
1237
1238static void ip_fib_net_exit(struct net *net)
1239{
1240 unsigned int i;
1241
1242 rtnl_lock();
1243#ifdef CONFIG_IP_MULTIPLE_TABLES
1244 RCU_INIT_POINTER(net->ipv4.fib_main, NULL);
1245 RCU_INIT_POINTER(net->ipv4.fib_default, NULL);
1246#endif
1247 for (i = 0; i < FIB_TABLE_HASHSZ; i++) {
1248 struct hlist_head *head = &net->ipv4.fib_table_hash[i];
1249 struct hlist_node *tmp;
1250 struct fib_table *tb;
1251
1252 hlist_for_each_entry_safe(tb, tmp, head, tb_hlist) {
1253 hlist_del(&tb->tb_hlist);
1254 fib_table_flush(net, tb);
1255 fib_free_table(tb);
1256 }
1257 }
1258
1259#ifdef CONFIG_IP_MULTIPLE_TABLES
1260 fib4_rules_exit(net);
1261#endif
1262 rtnl_unlock();
1263 kfree(net->ipv4.fib_table_hash);
1264}
1265
1266static int __net_init fib_net_init(struct net *net)
1267{
1268 int error;
1269
1270#ifdef CONFIG_IP_ROUTE_CLASSID
1271 net->ipv4.fib_num_tclassid_users = 0;
1272#endif
1273 error = ip_fib_net_init(net);
1274 if (error < 0)
1275 goto out;
1276 error = nl_fib_lookup_init(net);
1277 if (error < 0)
1278 goto out_nlfl;
1279 error = fib_proc_init(net);
1280 if (error < 0)
1281 goto out_proc;
1282out:
1283 return error;
1284
1285out_proc:
1286 nl_fib_lookup_exit(net);
1287out_nlfl:
1288 ip_fib_net_exit(net);
1289 goto out;
1290}
1291
1292static void __net_exit fib_net_exit(struct net *net)
1293{
1294 fib_proc_exit(net);
1295 nl_fib_lookup_exit(net);
1296 ip_fib_net_exit(net);
1297}
1298
1299static struct pernet_operations fib_net_ops = {
1300 .init = fib_net_init,
1301 .exit = fib_net_exit,
1302};
1303
1304void __init ip_fib_init(void)
1305{
1306 rtnl_register(PF_INET, RTM_NEWROUTE, inet_rtm_newroute, NULL, NULL);
1307 rtnl_register(PF_INET, RTM_DELROUTE, inet_rtm_delroute, NULL, NULL);
1308 rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib, NULL);
1309
1310 register_pernet_subsys(&fib_net_ops);
1311 register_netdevice_notifier(&fib_netdev_notifier);
1312 register_inetaddr_notifier(&fib_inetaddr_notifier);
1313
1314 fib_trie_init();
1315}
1316
