?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
initial commit with v3.6.7
[linux-3.6.7-moxart.git] / net / ipv4 / route.c
blobc017cb1634e571deff5d1032df18e889396111ca
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 * ROUTE - implementation of the IP router.
7 *
8 * Authors: Ross Biro
9 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
10 * Alan Cox, <gw4pts@gw4pts.ampr.org>
11 * Linus Torvalds, <Linus.Torvalds@helsinki.fi>
12 * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
13 *
14 * Fixes:
15 * Alan Cox : Verify area fixes.
16 * Alan Cox : cli() protects routing changes
17 * Rui Oliveira : ICMP routing table updates
18 * (rco@di.uminho.pt) Routing table insertion and update
19 * Linus Torvalds : Rewrote bits to be sensible
20 * Alan Cox : Added BSD route gw semantics
21 * Alan Cox : Super /proc >4K
22 * Alan Cox : MTU in route table
23 * Alan Cox : MSS actually. Also added the window
24 * clamper.
25 * Sam Lantinga : Fixed route matching in rt_del()
26 * Alan Cox : Routing cache support.
27 * Alan Cox : Removed compatibility cruft.
28 * Alan Cox : RTF_REJECT support.
29 * Alan Cox : TCP irtt support.
30 * Jonathan Naylor : Added Metric support.
31 * Miquel van Smoorenburg : BSD API fixes.
32 * Miquel van Smoorenburg : Metrics.
33 * Alan Cox : Use __u32 properly
34 * Alan Cox : Aligned routing errors more closely with BSD
35 * our system is still very different.
36 * Alan Cox : Faster /proc handling
37 * Alexey Kuznetsov : Massive rework to support tree based routing,
38 * routing caches and better behaviour.
39 *
40 * Olaf Erb : irtt wasn't being copied right.
41 * Bjorn Ekwall : Kerneld route support.
42 * Alan Cox : Multicast fixed (I hope)
43 * Pavel Krauz : Limited broadcast fixed
44 * Mike McLagan : Routing by source
45 * Alexey Kuznetsov : End of old history. Split to fib.c and
46 * route.c and rewritten from scratch.
47 * Andi Kleen : Load-limit warning messages.
48 * Vitaly E. Lavrov : Transparent proxy revived after year coma.
49 * Vitaly E. Lavrov : Race condition in ip_route_input_slow.
50 * Tobias Ringstrom : Uninitialized res.type in ip_route_output_slow.
51 * Vladimir V. Ivanov : IP rule info (flowid) is really useful.
52 * Marc Boucher : routing by fwmark
53 * Robert Olsson : Added rt_cache statistics
54 * Arnaldo C. Melo : Convert proc stuff to seq_file
55 * Eric Dumazet : hashed spinlocks and rt_check_expire() fixes.
56 * Ilia Sotnikov : Ignore TOS on PMTUD and Redirect
57 * Ilia Sotnikov : Removed TOS from hash calculations
58 *
59 * This program is free software; you can redistribute it and/or
60 * modify it under the terms of the GNU General Public License
61 * as published by the Free Software Foundation; either version
62 * 2 of the License, or (at your option) any later version.
63 */
64
65 #define pr_fmt(fmt) "IPv4: " fmt
66
67 #include <linux/module.h>
68 #include <asm/uaccess.h>
69 #include <linux/bitops.h>
70 #include <linux/types.h>
71 #include <linux/kernel.h>
72 #include <linux/mm.h>
73 #include <linux/string.h>
74 #include <linux/socket.h>
75 #include <linux/sockios.h>
76 #include <linux/errno.h>
77 #include <linux/in.h>
78 #include <linux/inet.h>
79 #include <linux/netdevice.h>
80 #include <linux/proc_fs.h>
81 #include <linux/init.h>
82 #include <linux/skbuff.h>
83 #include <linux/inetdevice.h>
84 #include <linux/igmp.h>
85 #include <linux/pkt_sched.h>
86 #include <linux/mroute.h>
87 #include <linux/netfilter_ipv4.h>
88 #include <linux/random.h>
89 #include <linux/rcupdate.h>
90 #include <linux/times.h>
91 #include <linux/slab.h>
92 #include <net/dst.h>
93 #include <net/net_namespace.h>
94 #include <net/protocol.h>
95 #include <net/ip.h>
96 #include <net/route.h>
97 #include <net/inetpeer.h>
98 #include <net/sock.h>
99 #include <net/ip_fib.h>
100 #include <net/arp.h>
101 #include <net/tcp.h>
102 #include <net/icmp.h>
103 #include <net/xfrm.h>
104 #include <net/netevent.h>
105 #include <net/rtnetlink.h>
106 #ifdef CONFIG_SYSCTL
107 #include <linux/sysctl.h>
108 #include <linux/kmemleak.h>
109 #endif
110 #include <net/secure_seq.h>
111
112 #define RT_FL_TOS(oldflp4) \
113 ((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK))
114
115 #define IP_MAX_MTU 0xFFF0
116
117 #define RT_GC_TIMEOUT (300*HZ)
118
119 static int ip_rt_max_size;
120 static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT;
121 static int ip_rt_gc_interval __read_mostly = 60 * HZ;
122 static int ip_rt_gc_min_interval __read_mostly = HZ / 2;
123 static int ip_rt_redirect_number __read_mostly = 9;
124 static int ip_rt_redirect_load __read_mostly = HZ / 50;
125 static int ip_rt_redirect_silence __read_mostly = ((HZ / 50) << (9 + 1));
126 static int ip_rt_error_cost __read_mostly = HZ;
127 static int ip_rt_error_burst __read_mostly = 5 * HZ;
128 static int ip_rt_gc_elasticity __read_mostly = 8;
129 static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ;
130 static int ip_rt_min_pmtu __read_mostly = 512 + 20 + 20;
131 static int ip_rt_min_advmss __read_mostly = 256;
132
133 /*
134 * Interface to generic destination cache.
135 */
136
137 static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie);
138 static unsigned int ipv4_default_advmss(const struct dst_entry *dst);
139 static unsigned int ipv4_mtu(const struct dst_entry *dst);
140 static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst);
141 static void ipv4_link_failure(struct sk_buff *skb);
142 static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
143 struct sk_buff *skb, u32 mtu);
144 static void ip_do_redirect(struct dst_entry *dst, struct sock *sk,
145 struct sk_buff *skb);
146 static void ipv4_dst_destroy(struct dst_entry *dst);
147
148 static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
149 int how)
150 {
151 }
152
153 static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old)
154 {
155 WARN_ON(1);
156 return NULL;
157 }
158
159 static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst,
160 struct sk_buff *skb,
161 const void *daddr);
162
163 static struct dst_ops ipv4_dst_ops = {
164 .family = AF_INET,
165 .protocol = cpu_to_be16(ETH_P_IP),
166 .check = ipv4_dst_check,
167 .default_advmss = ipv4_default_advmss,
168 .mtu = ipv4_mtu,
169 .cow_metrics = ipv4_cow_metrics,
170 .destroy = ipv4_dst_destroy,
171 .ifdown = ipv4_dst_ifdown,
172 .negative_advice = ipv4_negative_advice,
173 .link_failure = ipv4_link_failure,
174 .update_pmtu = ip_rt_update_pmtu,
175 .redirect = ip_do_redirect,
176 .local_out = __ip_local_out,
177 .neigh_lookup = ipv4_neigh_lookup,
178 };
179
180 #define ECN_OR_COST(class) TC_PRIO_##class
181
182 const __u8 ip_tos2prio[16] = {
183 TC_PRIO_BESTEFFORT,
184 ECN_OR_COST(BESTEFFORT),
185 TC_PRIO_BESTEFFORT,
186 ECN_OR_COST(BESTEFFORT),
187 TC_PRIO_BULK,
188 ECN_OR_COST(BULK),
189 TC_PRIO_BULK,
190 ECN_OR_COST(BULK),
191 TC_PRIO_INTERACTIVE,
192 ECN_OR_COST(INTERACTIVE),
193 TC_PRIO_INTERACTIVE,
194 ECN_OR_COST(INTERACTIVE),
195 TC_PRIO_INTERACTIVE_BULK,
196 ECN_OR_COST(INTERACTIVE_BULK),
197 TC_PRIO_INTERACTIVE_BULK,
198 ECN_OR_COST(INTERACTIVE_BULK)
199 };
200 EXPORT_SYMBOL(ip_tos2prio);
201
202 static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat);
203 #define RT_CACHE_STAT_INC(field) __this_cpu_inc(rt_cache_stat.field)
204
205 #ifdef CONFIG_PROC_FS
206 static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
207 {
208 if (*pos)
209 return NULL;
210 return SEQ_START_TOKEN;
211 }
212
213 static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
214 {
215 ++*pos;
216 return NULL;
217 }
218
219 static void rt_cache_seq_stop(struct seq_file *seq, void *v)
220 {
221 }
222
223 static int rt_cache_seq_show(struct seq_file *seq, void *v)
224 {
225 if (v == SEQ_START_TOKEN)
226 seq_printf(seq, "%-127s\n",
227 "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t"
228 "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t"
229 "HHUptod\tSpecDst");
230 return 0;
231 }
232
233 static const struct seq_operations rt_cache_seq_ops = {
234 .start = rt_cache_seq_start,
235 .next = rt_cache_seq_next,
236 .stop = rt_cache_seq_stop,
237 .show = rt_cache_seq_show,
238 };
239
240 static int rt_cache_seq_open(struct inode *inode, struct file *file)
241 {
242 return seq_open(file, &rt_cache_seq_ops);
243 }
244
245 static const struct file_operations rt_cache_seq_fops = {
246 .owner = THIS_MODULE,
247 .open = rt_cache_seq_open,
248 .read = seq_read,
249 .llseek = seq_lseek,
250 .release = seq_release,
251 };
252
253
254 static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos)
255 {
256 int cpu;
257
258 if (*pos == 0)
259 return SEQ_START_TOKEN;
260
261 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
262 if (!cpu_possible(cpu))
263 continue;
264 *pos = cpu+1;
265 return &per_cpu(rt_cache_stat, cpu);
266 }
267 return NULL;
268 }
269
270 static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos)
271 {
272 int cpu;
273
274 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
275 if (!cpu_possible(cpu))
276 continue;
277 *pos = cpu+1;
278 return &per_cpu(rt_cache_stat, cpu);
279 }
280 return NULL;
281
282 }
283
284 static void rt_cpu_seq_stop(struct seq_file *seq, void *v)
285 {
286
287 }
288
289 static int rt_cpu_seq_show(struct seq_file *seq, void *v)
290 {
291 struct rt_cache_stat *st = v;
292
293 if (v == SEQ_START_TOKEN) {
294 seq_printf(seq, "entries in_hit in_slow_tot in_slow_mc in_no_route in_brd in_martian_dst in_martian_src out_hit out_slow_tot out_slow_mc gc_total gc_ignored gc_goal_miss gc_dst_overflow in_hlist_search out_hlist_search\n");
295 return 0;
296 }
297
298 seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x "
299 " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n",
300 dst_entries_get_slow(&ipv4_dst_ops),
301 st->in_hit,
302 st->in_slow_tot,
303 st->in_slow_mc,
304 st->in_no_route,
305 st->in_brd,
306 st->in_martian_dst,
307 st->in_martian_src,
308
309 st->out_hit,
310 st->out_slow_tot,
311 st->out_slow_mc,
312
313 st->gc_total,
314 st->gc_ignored,
315 st->gc_goal_miss,
316 st->gc_dst_overflow,
317 st->in_hlist_search,
318 st->out_hlist_search
319 );
320 return 0;
321 }
322
323 static const struct seq_operations rt_cpu_seq_ops = {
324 .start = rt_cpu_seq_start,
325 .next = rt_cpu_seq_next,
326 .stop = rt_cpu_seq_stop,
327 .show = rt_cpu_seq_show,
328 };
329
330
331 static int rt_cpu_seq_open(struct inode *inode, struct file *file)
332 {
333 return seq_open(file, &rt_cpu_seq_ops);
334 }
335
336 static const struct file_operations rt_cpu_seq_fops = {
337 .owner = THIS_MODULE,
338 .open = rt_cpu_seq_open,
339 .read = seq_read,
340 .llseek = seq_lseek,
341 .release = seq_release,
342 };
343
344 #ifdef CONFIG_IP_ROUTE_CLASSID
345 static int rt_acct_proc_show(struct seq_file *m, void *v)
346 {
347 struct ip_rt_acct *dst, *src;
348 unsigned int i, j;
349
350 dst = kcalloc(256, sizeof(struct ip_rt_acct), GFP_KERNEL);
351 if (!dst)
352 return -ENOMEM;
353
354 for_each_possible_cpu(i) {
355 src = (struct ip_rt_acct *)per_cpu_ptr(ip_rt_acct, i);
356 for (j = 0; j < 256; j++) {
357 dst[j].o_bytes += src[j].o_bytes;
358 dst[j].o_packets += src[j].o_packets;
359 dst[j].i_bytes += src[j].i_bytes;
360 dst[j].i_packets += src[j].i_packets;
361 }
362 }
363
364 seq_write(m, dst, 256 * sizeof(struct ip_rt_acct));
365 kfree(dst);
366 return 0;
367 }
368
369 static int rt_acct_proc_open(struct inode *inode, struct file *file)
370 {
371 return single_open(file, rt_acct_proc_show, NULL);
372 }
373
374 static const struct file_operations rt_acct_proc_fops = {
375 .owner = THIS_MODULE,
376 .open = rt_acct_proc_open,
377 .read = seq_read,
378 .llseek = seq_lseek,
379 .release = single_release,
380 };
381 #endif
382
383 static int __net_init ip_rt_do_proc_init(struct net *net)
384 {
385 struct proc_dir_entry *pde;
386
387 pde = proc_net_fops_create(net, "rt_cache", S_IRUGO,
388 &rt_cache_seq_fops);
389 if (!pde)
390 goto err1;
391
392 pde = proc_create("rt_cache", S_IRUGO,
393 net->proc_net_stat, &rt_cpu_seq_fops);
394 if (!pde)
395 goto err2;
396
397 #ifdef CONFIG_IP_ROUTE_CLASSID
398 pde = proc_create("rt_acct", 0, net->proc_net, &rt_acct_proc_fops);
399 if (!pde)
400 goto err3;
401 #endif
402 return 0;
403
404 #ifdef CONFIG_IP_ROUTE_CLASSID
405 err3:
406 remove_proc_entry("rt_cache", net->proc_net_stat);
407 #endif
408 err2:
409 remove_proc_entry("rt_cache", net->proc_net);
410 err1:
411 return -ENOMEM;
412 }
413
414 static void __net_exit ip_rt_do_proc_exit(struct net *net)
415 {
416 remove_proc_entry("rt_cache", net->proc_net_stat);
417 remove_proc_entry("rt_cache", net->proc_net);
418 #ifdef CONFIG_IP_ROUTE_CLASSID
419 remove_proc_entry("rt_acct", net->proc_net);
420 #endif
421 }
422
423 static struct pernet_operations ip_rt_proc_ops __net_initdata = {
424 .init = ip_rt_do_proc_init,
425 .exit = ip_rt_do_proc_exit,
426 };
427
428 static int __init ip_rt_proc_init(void)
429 {
430 return register_pernet_subsys(&ip_rt_proc_ops);
431 }
432
433 #else
434 static inline int ip_rt_proc_init(void)
435 {
436 return 0;
437 }
438 #endif /* CONFIG_PROC_FS */
439
440 static inline bool rt_is_expired(const struct rtable *rth)
441 {
442 return rth->rt_genid != rt_genid(dev_net(rth->dst.dev));
443 }
444
445 void rt_cache_flush(struct net *net)
446 {
447 rt_genid_bump(net);
448 }
449
450 static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst,
451 struct sk_buff *skb,
452 const void *daddr)
453 {
454 struct net_device *dev = dst->dev;
455 const __be32 *pkey = daddr;
456 const struct rtable *rt;
457 struct neighbour *n;
458
459 rt = (const struct rtable *) dst;
460 if (rt->rt_gateway)
461 pkey = (const __be32 *) &rt->rt_gateway;
462 else if (skb)
463 pkey = &ip_hdr(skb)->daddr;
464
465 n = __ipv4_neigh_lookup(dev, *(__force u32 *)pkey);
466 if (n)
467 return n;
468 return neigh_create(&arp_tbl, pkey, dev);
469 }
470
471 /*
472 * Peer allocation may fail only in serious out-of-memory conditions. However
473 * we still can generate some output.
474 * Random ID selection looks a bit dangerous because we have no chances to
475 * select ID being unique in a reasonable period of time.
476 * But broken packet identifier may be better than no packet at all.
477 */
478 static void ip_select_fb_ident(struct iphdr *iph)
479 {
480 static DEFINE_SPINLOCK(ip_fb_id_lock);
481 static u32 ip_fallback_id;
482 u32 salt;
483
484 spin_lock_bh(&ip_fb_id_lock);
485 salt = secure_ip_id((__force __be32)ip_fallback_id ^ iph->daddr);
486 iph->id = htons(salt & 0xFFFF);
487 ip_fallback_id = salt;
488 spin_unlock_bh(&ip_fb_id_lock);
489 }
490
491 void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more)
492 {
493 struct net *net = dev_net(dst->dev);
494 struct inet_peer *peer;
495
496 peer = inet_getpeer_v4(net->ipv4.peers, iph->daddr, 1);
497 if (peer) {
498 iph->id = htons(inet_getid(peer, more));
499 inet_putpeer(peer);
500 return;
501 }
502
503 ip_select_fb_ident(iph);
504 }
505 EXPORT_SYMBOL(__ip_select_ident);
506
507 static void __build_flow_key(struct flowi4 *fl4, const struct sock *sk,
508 const struct iphdr *iph,
509 int oif, u8 tos,
510 u8 prot, u32 mark, int flow_flags)
511 {
512 if (sk) {
513 const struct inet_sock *inet = inet_sk(sk);
514
515 oif = sk->sk_bound_dev_if;
516 mark = sk->sk_mark;
517 tos = RT_CONN_FLAGS(sk);
518 prot = inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol;
519 }
520 flowi4_init_output(fl4, oif, mark, tos,
521 RT_SCOPE_UNIVERSE, prot,
522 flow_flags,
523 iph->daddr, iph->saddr, 0, 0);
524 }
525
526 static void build_skb_flow_key(struct flowi4 *fl4, const struct sk_buff *skb,
527 const struct sock *sk)
528 {
529 const struct iphdr *iph = ip_hdr(skb);
530 int oif = skb->dev->ifindex;
531 u8 tos = RT_TOS(iph->tos);
532 u8 prot = iph->protocol;
533 u32 mark = skb->mark;
534
535 __build_flow_key(fl4, sk, iph, oif, tos, prot, mark, 0);
536 }
537
538 static void build_sk_flow_key(struct flowi4 *fl4, const struct sock *sk)
539 {
540 const struct inet_sock *inet = inet_sk(sk);
541 const struct ip_options_rcu *inet_opt;
542 __be32 daddr = inet->inet_daddr;
543
544 rcu_read_lock();
545 inet_opt = rcu_dereference(inet->inet_opt);
546 if (inet_opt && inet_opt->opt.srr)
547 daddr = inet_opt->opt.faddr;
548 flowi4_init_output(fl4, sk->sk_bound_dev_if, sk->sk_mark,
549 RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE,
550 inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol,
551 inet_sk_flowi_flags(sk),
552 daddr, inet->inet_saddr, 0, 0);
553 rcu_read_unlock();
554 }
555
556 static void ip_rt_build_flow_key(struct flowi4 *fl4, const struct sock *sk,
557 const struct sk_buff *skb)
558 {
559 if (skb)
560 build_skb_flow_key(fl4, skb, sk);
561 else
562 build_sk_flow_key(fl4, sk);
563 }
564
565 static inline void rt_free(struct rtable *rt)
566 {
567 call_rcu(&rt->dst.rcu_head, dst_rcu_free);
568 }
569
570 static DEFINE_SPINLOCK(fnhe_lock);
571
572 static struct fib_nh_exception *fnhe_oldest(struct fnhe_hash_bucket *hash)
573 {
574 struct fib_nh_exception *fnhe, *oldest;
575 struct rtable *orig;
576
577 oldest = rcu_dereference(hash->chain);
578 for (fnhe = rcu_dereference(oldest->fnhe_next); fnhe;
579 fnhe = rcu_dereference(fnhe->fnhe_next)) {
580 if (time_before(fnhe->fnhe_stamp, oldest->fnhe_stamp))
581 oldest = fnhe;
582 }
583 orig = rcu_dereference(oldest->fnhe_rth);
584 if (orig) {
585 RCU_INIT_POINTER(oldest->fnhe_rth, NULL);
586 rt_free(orig);
587 }
588 return oldest;
589 }
590
591 static inline u32 fnhe_hashfun(__be32 daddr)
592 {
593 u32 hval;
594
595 hval = (__force u32) daddr;
596 hval ^= (hval >> 11) ^ (hval >> 22);
597
598 return hval & (FNHE_HASH_SIZE - 1);
599 }
600
601 static void update_or_create_fnhe(struct fib_nh *nh, __be32 daddr, __be32 gw,
602 u32 pmtu, unsigned long expires)
603 {
604 struct fnhe_hash_bucket *hash;
605 struct fib_nh_exception *fnhe;
606 int depth;
607 u32 hval = fnhe_hashfun(daddr);
608
609 spin_lock_bh(&fnhe_lock);
610
611 hash = nh->nh_exceptions;
612 if (!hash) {
613 hash = kzalloc(FNHE_HASH_SIZE * sizeof(*hash), GFP_ATOMIC);
614 if (!hash)
615 goto out_unlock;
616 nh->nh_exceptions = hash;
617 }
618
619 hash += hval;
620
621 depth = 0;
622 for (fnhe = rcu_dereference(hash->chain); fnhe;
623 fnhe = rcu_dereference(fnhe->fnhe_next)) {
624 if (fnhe->fnhe_daddr == daddr)
625 break;
626 depth++;
627 }
628
629 if (fnhe) {
630 if (gw)
631 fnhe->fnhe_gw = gw;
632 if (pmtu) {
633 fnhe->fnhe_pmtu = pmtu;
634 fnhe->fnhe_expires = expires;
635 }
636 } else {
637 if (depth > FNHE_RECLAIM_DEPTH)
638 fnhe = fnhe_oldest(hash);
639 else {
640 fnhe = kzalloc(sizeof(*fnhe), GFP_ATOMIC);
641 if (!fnhe)
642 goto out_unlock;
643
644 fnhe->fnhe_next = hash->chain;
645 rcu_assign_pointer(hash->chain, fnhe);
646 }
647 fnhe->fnhe_daddr = daddr;
648 fnhe->fnhe_gw = gw;
649 fnhe->fnhe_pmtu = pmtu;
650 fnhe->fnhe_expires = expires;
651 }
652
653 fnhe->fnhe_stamp = jiffies;
654
655 out_unlock:
656 spin_unlock_bh(&fnhe_lock);
657 return;
658 }
659
660 static void __ip_do_redirect(struct rtable *rt, struct sk_buff *skb, struct flowi4 *fl4,
661 bool kill_route)
662 {
663 __be32 new_gw = icmp_hdr(skb)->un.gateway;
664 __be32 old_gw = ip_hdr(skb)->saddr;
665 struct net_device *dev = skb->dev;
666 struct in_device *in_dev;
667 struct fib_result res;
668 struct neighbour *n;
669 struct net *net;
670
671 switch (icmp_hdr(skb)->code & 7) {
672 case ICMP_REDIR_NET:
673 case ICMP_REDIR_NETTOS:
674 case ICMP_REDIR_HOST:
675 case ICMP_REDIR_HOSTTOS:
676 break;
677
678 default:
679 return;
680 }
681
682 if (rt->rt_gateway != old_gw)
683 return;
684
685 in_dev = __in_dev_get_rcu(dev);
686 if (!in_dev)
687 return;
688
689 net = dev_net(dev);
690 if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) ||
691 ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) ||
692 ipv4_is_zeronet(new_gw))
693 goto reject_redirect;
694
695 if (!IN_DEV_SHARED_MEDIA(in_dev)) {
696 if (!inet_addr_onlink(in_dev, new_gw, old_gw))
697 goto reject_redirect;
698 if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev))
699 goto reject_redirect;
700 } else {
701 if (inet_addr_type(net, new_gw) != RTN_UNICAST)
702 goto reject_redirect;
703 }
704
705 n = ipv4_neigh_lookup(&rt->dst, NULL, &new_gw);
706 if (n) {
707 if (!(n->nud_state & NUD_VALID)) {
708 neigh_event_send(n, NULL);
709 } else {
710 if (fib_lookup(net, fl4, &res) == 0) {
711 struct fib_nh *nh = &FIB_RES_NH(res);
712
713 update_or_create_fnhe(nh, fl4->daddr, new_gw,
714 0, 0);
715 }
716 if (kill_route)
717 rt->dst.obsolete = DST_OBSOLETE_KILL;
718 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n);
719 }
720 neigh_release(n);
721 }
722 return;
723
724 reject_redirect:
725 #ifdef CONFIG_IP_ROUTE_VERBOSE
726 if (IN_DEV_LOG_MARTIANS(in_dev)) {
727 const struct iphdr *iph = (const struct iphdr *) skb->data;
728 __be32 daddr = iph->daddr;
729 __be32 saddr = iph->saddr;
730
731 net_info_ratelimited("Redirect from %pI4 on %s about %pI4 ignored\n"
732 " Advised path = %pI4 -> %pI4\n",
733 &old_gw, dev->name, &new_gw,
734 &saddr, &daddr);
735 }
736 #endif
737 ;
738 }
739
740 static void ip_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
741 {
742 struct rtable *rt;
743 struct flowi4 fl4;
744
745 rt = (struct rtable *) dst;
746
747 ip_rt_build_flow_key(&fl4, sk, skb);
748 __ip_do_redirect(rt, skb, &fl4, true);
749 }
750
751 static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
752 {
753 struct rtable *rt = (struct rtable *)dst;
754 struct dst_entry *ret = dst;
755
756 if (rt) {
757 if (dst->obsolete > 0) {
758 ip_rt_put(rt);
759 ret = NULL;
760 } else if ((rt->rt_flags & RTCF_REDIRECTED) ||
761 rt->dst.expires) {
762 ip_rt_put(rt);
763 ret = NULL;
764 }
765 }
766 return ret;
767 }
768
769 /*
770 * Algorithm:
771 * 1. The first ip_rt_redirect_number redirects are sent
772 * with exponential backoff, then we stop sending them at all,
773 * assuming that the host ignores our redirects.
774 * 2. If we did not see packets requiring redirects
775 * during ip_rt_redirect_silence, we assume that the host
776 * forgot redirected route and start to send redirects again.
777 *
778 * This algorithm is much cheaper and more intelligent than dumb load limiting
779 * in icmp.c.
780 *
781 * NOTE. Do not forget to inhibit load limiting for redirects (redundant)
782 * and "frag. need" (breaks PMTU discovery) in icmp.c.
783 */
784
785 void ip_rt_send_redirect(struct sk_buff *skb)
786 {
787 struct rtable *rt = skb_rtable(skb);
788 struct in_device *in_dev;
789 struct inet_peer *peer;
790 struct net *net;
791 int log_martians;
792
793 rcu_read_lock();
794 in_dev = __in_dev_get_rcu(rt->dst.dev);
795 if (!in_dev || !IN_DEV_TX_REDIRECTS(in_dev)) {
796 rcu_read_unlock();
797 return;
798 }
799 log_martians = IN_DEV_LOG_MARTIANS(in_dev);
800 rcu_read_unlock();
801
802 net = dev_net(rt->dst.dev);
803 peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, 1);
804 if (!peer) {
805 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST,
806 rt_nexthop(rt, ip_hdr(skb)->daddr));
807 return;
808 }
809
810 /* No redirected packets during ip_rt_redirect_silence;
811 * reset the algorithm.
812 */
813 if (time_after(jiffies, peer->rate_last + ip_rt_redirect_silence))
814 peer->rate_tokens = 0;
815
816 /* Too many ignored redirects; do not send anything
817 * set dst.rate_last to the last seen redirected packet.
818 */
819 if (peer->rate_tokens >= ip_rt_redirect_number) {
820 peer->rate_last = jiffies;
821 goto out_put_peer;
822 }
823
824 /* Check for load limit; set rate_last to the latest sent
825 * redirect.
826 */
827 if (peer->rate_tokens == 0 ||
828 time_after(jiffies,
829 (peer->rate_last +
830 (ip_rt_redirect_load << peer->rate_tokens)))) {
831 __be32 gw = rt_nexthop(rt, ip_hdr(skb)->daddr);
832
833 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, gw);
834 peer->rate_last = jiffies;
835 ++peer->rate_tokens;
836 #ifdef CONFIG_IP_ROUTE_VERBOSE
837 if (log_martians &&
838 peer->rate_tokens == ip_rt_redirect_number)
839 net_warn_ratelimited("host %pI4/if%d ignores redirects for %pI4 to %pI4\n",
840 &ip_hdr(skb)->saddr, inet_iif(skb),
841 &ip_hdr(skb)->daddr, &gw);
842 #endif
843 }
844 out_put_peer:
845 inet_putpeer(peer);
846 }
847
848 static int ip_error(struct sk_buff *skb)
849 {
850 struct in_device *in_dev = __in_dev_get_rcu(skb->dev);
851 struct rtable *rt = skb_rtable(skb);
852 struct inet_peer *peer;
853 unsigned long now;
854 struct net *net;
855 bool send;
856 int code;
857
858 net = dev_net(rt->dst.dev);
859 if (!IN_DEV_FORWARD(in_dev)) {
860 switch (rt->dst.error) {
861 case EHOSTUNREACH:
862 IP_INC_STATS_BH(net, IPSTATS_MIB_INADDRERRORS);
863 break;
864
865 case ENETUNREACH:
866 IP_INC_STATS_BH(net, IPSTATS_MIB_INNOROUTES);
867 break;
868 }
869 goto out;
870 }
871
872 switch (rt->dst.error) {
873 case EINVAL:
874 default:
875 goto out;
876 case EHOSTUNREACH:
877 code = ICMP_HOST_UNREACH;
878 break;
879 case ENETUNREACH:
880 code = ICMP_NET_UNREACH;
881 IP_INC_STATS_BH(net, IPSTATS_MIB_INNOROUTES);
882 break;
883 case EACCES:
884 code = ICMP_PKT_FILTERED;
885 break;
886 }
887
888 peer = inet_getpeer_v4(net->ipv4.peers, ip_hdr(skb)->saddr, 1);
889
890 send = true;
891 if (peer) {
892 now = jiffies;
893 peer->rate_tokens += now - peer->rate_last;
894 if (peer->rate_tokens > ip_rt_error_burst)
895 peer->rate_tokens = ip_rt_error_burst;
896 peer->rate_last = now;
897 if (peer->rate_tokens >= ip_rt_error_cost)
898 peer->rate_tokens -= ip_rt_error_cost;
899 else
900 send = false;
901 inet_putpeer(peer);
902 }
903 if (send)
904 icmp_send(skb, ICMP_DEST_UNREACH, code, 0);
905
906 out: kfree_skb(skb);
907 return 0;
908 }
909
910 static void __ip_rt_update_pmtu(struct rtable *rt, struct flowi4 *fl4, u32 mtu)
911 {
912 struct dst_entry *dst = &rt->dst;
913 struct fib_result res;
914
915 if (dst->dev->mtu < mtu)
916 return;
917
918 if (mtu < ip_rt_min_pmtu)
919 mtu = ip_rt_min_pmtu;
920
921 if (!rt->rt_pmtu) {
922 dst->obsolete = DST_OBSOLETE_KILL;
923 } else {
924 rt->rt_pmtu = mtu;
925 dst->expires = max(1UL, jiffies + ip_rt_mtu_expires);
926 }
927
928 rcu_read_lock();
929 if (fib_lookup(dev_net(dst->dev), fl4, &res) == 0) {
930 struct fib_nh *nh = &FIB_RES_NH(res);
931
932 update_or_create_fnhe(nh, fl4->daddr, 0, mtu,
933 jiffies + ip_rt_mtu_expires);
934 }
935 rcu_read_unlock();
936 }
937
938 static void ip_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
939 struct sk_buff *skb, u32 mtu)
940 {
941 struct rtable *rt = (struct rtable *) dst;
942 struct flowi4 fl4;
943
944 ip_rt_build_flow_key(&fl4, sk, skb);
945 __ip_rt_update_pmtu(rt, &fl4, mtu);
946 }
947
948 void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu,
949 int oif, u32 mark, u8 protocol, int flow_flags)
950 {
951 const struct iphdr *iph = (const struct iphdr *) skb->data;
952 struct flowi4 fl4;
953 struct rtable *rt;
954
955 __build_flow_key(&fl4, NULL, iph, oif,
956 RT_TOS(iph->tos), protocol, mark, flow_flags);
957 rt = __ip_route_output_key(net, &fl4);
958 if (!IS_ERR(rt)) {
959 __ip_rt_update_pmtu(rt, &fl4, mtu);
960 ip_rt_put(rt);
961 }
962 }
963 EXPORT_SYMBOL_GPL(ipv4_update_pmtu);
964
965 void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu)
966 {
967 const struct iphdr *iph = (const struct iphdr *) skb->data;
968 struct flowi4 fl4;
969 struct rtable *rt;
970
971 __build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0);
972 rt = __ip_route_output_key(sock_net(sk), &fl4);
973 if (!IS_ERR(rt)) {
974 __ip_rt_update_pmtu(rt, &fl4, mtu);
975 ip_rt_put(rt);
976 }
977 }
978 EXPORT_SYMBOL_GPL(ipv4_sk_update_pmtu);
979
980 void ipv4_redirect(struct sk_buff *skb, struct net *net,
981 int oif, u32 mark, u8 protocol, int flow_flags)
982 {
983 const struct iphdr *iph = (const struct iphdr *) skb->data;
984 struct flowi4 fl4;
985 struct rtable *rt;
986
987 __build_flow_key(&fl4, NULL, iph, oif,
988 RT_TOS(iph->tos), protocol, mark, flow_flags);
989 rt = __ip_route_output_key(net, &fl4);
990 if (!IS_ERR(rt)) {
991 __ip_do_redirect(rt, skb, &fl4, false);
992 ip_rt_put(rt);
993 }
994 }
995 EXPORT_SYMBOL_GPL(ipv4_redirect);
996
997 void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk)
998 {
999 const struct iphdr *iph = (const struct iphdr *) skb->data;
1000 struct flowi4 fl4;
1001 struct rtable *rt;
1002
1003 __build_flow_key(&fl4, sk, iph, 0, 0, 0, 0, 0);
1004 rt = __ip_route_output_key(sock_net(sk), &fl4);
1005 if (!IS_ERR(rt)) {
1006 __ip_do_redirect(rt, skb, &fl4, false);
1007 ip_rt_put(rt);
1008 }
1009 }
1010 EXPORT_SYMBOL_GPL(ipv4_sk_redirect);
1011
1012 static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
1013 {
1014 struct rtable *rt = (struct rtable *) dst;
1015
1016 /* All IPV4 dsts are created with ->obsolete set to the value
1017 * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1018 * into this function always.
1019 *
1020 * When a PMTU/redirect information update invalidates a
1021 * route, this is indicated by setting obsolete to
1022 * DST_OBSOLETE_KILL.
1023 */
1024 if (dst->obsolete == DST_OBSOLETE_KILL || rt_is_expired(rt))
1025 return NULL;
1026 return dst;
1027 }
1028
1029 static void ipv4_link_failure(struct sk_buff *skb)
1030 {
1031 struct rtable *rt;
1032
1033 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
1034
1035 rt = skb_rtable(skb);
1036 if (rt)
1037 dst_set_expires(&rt->dst, 0);
1038 }
1039
1040 static int ip_rt_bug(struct sk_buff *skb)
1041 {
1042 pr_debug("%s: %pI4 -> %pI4, %s\n",
1043 __func__, &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr,
1044 skb->dev ? skb->dev->name : "?");
1045 kfree_skb(skb);
1046 WARN_ON(1);
1047 return 0;
1048 }
1049
1050 /*
1051 We do not cache source address of outgoing interface,
1052 because it is used only by IP RR, TS and SRR options,
1053 so that it out of fast path.
1054
1055 BTW remember: "addr" is allowed to be not aligned
1056 in IP options!
1057 */
1058
1059 void ip_rt_get_source(u8 *addr, struct sk_buff *skb, struct rtable *rt)
1060 {
1061 __be32 src;
1062
1063 if (rt_is_output_route(rt))
1064 src = ip_hdr(skb)->saddr;
1065 else {
1066 struct fib_result res;
1067 struct flowi4 fl4;
1068 struct iphdr *iph;
1069
1070 iph = ip_hdr(skb);
1071
1072 memset(&fl4, 0, sizeof(fl4));
1073 fl4.daddr = iph->daddr;
1074 fl4.saddr = iph->saddr;
1075 fl4.flowi4_tos = RT_TOS(iph->tos);
1076 fl4.flowi4_oif = rt->dst.dev->ifindex;
1077 fl4.flowi4_iif = skb->dev->ifindex;
1078 fl4.flowi4_mark = skb->mark;
1079
1080 rcu_read_lock();
1081 if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res) == 0)
1082 src = FIB_RES_PREFSRC(dev_net(rt->dst.dev), res);
1083 else
1084 src = inet_select_addr(rt->dst.dev,
1085 rt_nexthop(rt, iph->daddr),
1086 RT_SCOPE_UNIVERSE);
1087 rcu_read_unlock();
1088 }
1089 memcpy(addr, &src, 4);
1090 }
1091
1092 #ifdef CONFIG_IP_ROUTE_CLASSID
1093 static void set_class_tag(struct rtable *rt, u32 tag)
1094 {
1095 if (!(rt->dst.tclassid & 0xFFFF))
1096 rt->dst.tclassid |= tag & 0xFFFF;
1097 if (!(rt->dst.tclassid & 0xFFFF0000))
1098 rt->dst.tclassid |= tag & 0xFFFF0000;
1099 }
1100 #endif
1101
1102 static unsigned int ipv4_default_advmss(const struct dst_entry *dst)
1103 {
1104 unsigned int advmss = dst_metric_raw(dst, RTAX_ADVMSS);
1105
1106 if (advmss == 0) {
1107 advmss = max_t(unsigned int, dst->dev->mtu - 40,
1108 ip_rt_min_advmss);
1109 if (advmss > 65535 - 40)
1110 advmss = 65535 - 40;
1111 }
1112 return advmss;
1113 }
1114
1115 static unsigned int ipv4_mtu(const struct dst_entry *dst)
1116 {
1117 const struct rtable *rt = (const struct rtable *) dst;
1118 unsigned int mtu = rt->rt_pmtu;
1119
1120 if (mtu && time_after_eq(jiffies, rt->dst.expires))
1121 mtu = 0;
1122
1123 if (!mtu)
1124 mtu = dst_metric_raw(dst, RTAX_MTU);
1125
1126 if (mtu && rt_is_output_route(rt))
1127 return mtu;
1128
1129 mtu = dst->dev->mtu;
1130
1131 if (unlikely(dst_metric_locked(dst, RTAX_MTU))) {
1132 if (rt->rt_uses_gateway && mtu > 576)
1133 mtu = 576;
1134 }
1135
1136 if (mtu > IP_MAX_MTU)
1137 mtu = IP_MAX_MTU;
1138
1139 return mtu;
1140 }
1141
1142 static struct fib_nh_exception *find_exception(struct fib_nh *nh, __be32 daddr)
1143 {
1144 struct fnhe_hash_bucket *hash = nh->nh_exceptions;
1145 struct fib_nh_exception *fnhe;
1146 u32 hval;
1147
1148 if (!hash)
1149 return NULL;
1150
1151 hval = fnhe_hashfun(daddr);
1152
1153 for (fnhe = rcu_dereference(hash[hval].chain); fnhe;
1154 fnhe = rcu_dereference(fnhe->fnhe_next)) {
1155 if (fnhe->fnhe_daddr == daddr)
1156 return fnhe;
1157 }
1158 return NULL;
1159 }
1160
1161 static bool rt_bind_exception(struct rtable *rt, struct fib_nh_exception *fnhe,
1162 __be32 daddr)
1163 {
1164 bool ret = false;
1165
1166 spin_lock_bh(&fnhe_lock);
1167
1168 if (daddr == fnhe->fnhe_daddr) {
1169 struct rtable *orig = rcu_dereference(fnhe->fnhe_rth);
1170 if (orig && rt_is_expired(orig)) {
1171 fnhe->fnhe_gw = 0;
1172 fnhe->fnhe_pmtu = 0;
1173 fnhe->fnhe_expires = 0;
1174 }
1175 if (fnhe->fnhe_pmtu) {
1176 unsigned long expires = fnhe->fnhe_expires;
1177 unsigned long diff = expires - jiffies;
1178
1179 if (time_before(jiffies, expires)) {
1180 rt->rt_pmtu = fnhe->fnhe_pmtu;
1181 dst_set_expires(&rt->dst, diff);
1182 }
1183 }
1184 if (fnhe->fnhe_gw) {
1185 rt->rt_flags |= RTCF_REDIRECTED;
1186 rt->rt_gateway = fnhe->fnhe_gw;
1187 rt->rt_uses_gateway = 1;
1188 } else if (!rt->rt_gateway)
1189 rt->rt_gateway = daddr;
1190
1191 rcu_assign_pointer(fnhe->fnhe_rth, rt);
1192 if (orig)
1193 rt_free(orig);
1194
1195 fnhe->fnhe_stamp = jiffies;
1196 ret = true;
1197 }
1198 spin_unlock_bh(&fnhe_lock);
1199
1200 return ret;
1201 }
1202
1203 static bool rt_cache_route(struct fib_nh *nh, struct rtable *rt)
1204 {
1205 struct rtable *orig, *prev, **p;
1206 bool ret = true;
1207
1208 if (rt_is_input_route(rt)) {
1209 p = (struct rtable **)&nh->nh_rth_input;
1210 } else {
1211 p = (struct rtable **)__this_cpu_ptr(nh->nh_pcpu_rth_output);
1212 }
1213 orig = *p;
1214
1215 prev = cmpxchg(p, orig, rt);
1216 if (prev == orig) {
1217 if (orig)
1218 rt_free(orig);
1219 } else
1220 ret = false;
1221
1222 return ret;
1223 }
1224
1225 static DEFINE_SPINLOCK(rt_uncached_lock);
1226 static LIST_HEAD(rt_uncached_list);
1227
1228 static void rt_add_uncached_list(struct rtable *rt)
1229 {
1230 spin_lock_bh(&rt_uncached_lock);
1231 list_add_tail(&rt->rt_uncached, &rt_uncached_list);
1232 spin_unlock_bh(&rt_uncached_lock);
1233 }
1234
1235 static void ipv4_dst_destroy(struct dst_entry *dst)
1236 {
1237 struct rtable *rt = (struct rtable *) dst;
1238
1239 if (!list_empty(&rt->rt_uncached)) {
1240 spin_lock_bh(&rt_uncached_lock);
1241 list_del(&rt->rt_uncached);
1242 spin_unlock_bh(&rt_uncached_lock);
1243 }
1244 }
1245
1246 void rt_flush_dev(struct net_device *dev)
1247 {
1248 if (!list_empty(&rt_uncached_list)) {
1249 struct net *net = dev_net(dev);
1250 struct rtable *rt;
1251
1252 spin_lock_bh(&rt_uncached_lock);
1253 list_for_each_entry(rt, &rt_uncached_list, rt_uncached) {
1254 if (rt->dst.dev != dev)
1255 continue;
1256 rt->dst.dev = net->loopback_dev;
1257 dev_hold(rt->dst.dev);
1258 dev_put(dev);
1259 }
1260 spin_unlock_bh(&rt_uncached_lock);
1261 }
1262 }
1263
1264 static bool rt_cache_valid(const struct rtable *rt)
1265 {
1266 return rt &&
1267 rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1268 !rt_is_expired(rt);
1269 }
1270
1271 static void rt_set_nexthop(struct rtable *rt, __be32 daddr,
1272 const struct fib_result *res,
1273 struct fib_nh_exception *fnhe,
1274 struct fib_info *fi, u16 type, u32 itag)
1275 {
1276 bool cached = false;
1277
1278 if (fi) {
1279 struct fib_nh *nh = &FIB_RES_NH(*res);
1280
1281 if (nh->nh_gw && nh->nh_scope == RT_SCOPE_LINK) {
1282 rt->rt_gateway = nh->nh_gw;
1283 rt->rt_uses_gateway = 1;
1284 }
1285 dst_init_metrics(&rt->dst, fi->fib_metrics, true);
1286 #ifdef CONFIG_IP_ROUTE_CLASSID
1287 rt->dst.tclassid = nh->nh_tclassid;
1288 #endif
1289 if (unlikely(fnhe))
1290 cached = rt_bind_exception(rt, fnhe, daddr);
1291 else if (!(rt->dst.flags & DST_NOCACHE))
1292 cached = rt_cache_route(nh, rt);
1293 if (unlikely(!cached)) {
1294 /* Routes we intend to cache in nexthop exception or
1295 * FIB nexthop have the DST_NOCACHE bit clear.
1296 * However, if we are unsuccessful at storing this
1297 * route into the cache we really need to set it.
1298 */
1299 rt->dst.flags |= DST_NOCACHE;
1300 if (!rt->rt_gateway)
1301 rt->rt_gateway = daddr;
1302 rt_add_uncached_list(rt);
1303 }
1304 } else
1305 rt_add_uncached_list(rt);
1306
1307 #ifdef CONFIG_IP_ROUTE_CLASSID
1308 #ifdef CONFIG_IP_MULTIPLE_TABLES
1309 set_class_tag(rt, res->tclassid);
1310 #endif
1311 set_class_tag(rt, itag);
1312 #endif
1313 }
1314
1315 static struct rtable *rt_dst_alloc(struct net_device *dev,
1316 bool nopolicy, bool noxfrm, bool will_cache)
1317 {
1318 return dst_alloc(&ipv4_dst_ops, dev, 1, DST_OBSOLETE_FORCE_CHK,
1319 (will_cache ? 0 : (DST_HOST | DST_NOCACHE)) |
1320 (nopolicy ? DST_NOPOLICY : 0) |
1321 (noxfrm ? DST_NOXFRM : 0));
1322 }
1323
1324 /* called in rcu_read_lock() section */
1325 static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1326 u8 tos, struct net_device *dev, int our)
1327 {
1328 struct rtable *rth;
1329 struct in_device *in_dev = __in_dev_get_rcu(dev);
1330 u32 itag = 0;
1331 int err;
1332
1333 /* Primary sanity checks. */
1334
1335 if (in_dev == NULL)
1336 return -EINVAL;
1337
1338 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) ||
1339 skb->protocol != htons(ETH_P_IP))
1340 goto e_inval;
1341
1342 if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev)))
1343 if (ipv4_is_loopback(saddr))
1344 goto e_inval;
1345
1346 if (ipv4_is_zeronet(saddr)) {
1347 if (!ipv4_is_local_multicast(daddr))
1348 goto e_inval;
1349 } else {
1350 err = fib_validate_source(skb, saddr, 0, tos, 0, dev,
1351 in_dev, &itag);
1352 if (err < 0)
1353 goto e_err;
1354 }
1355 rth = rt_dst_alloc(dev_net(dev)->loopback_dev,
1356 IN_DEV_CONF_GET(in_dev, NOPOLICY), false, false);
1357 if (!rth)
1358 goto e_nobufs;
1359
1360 #ifdef CONFIG_IP_ROUTE_CLASSID
1361 rth->dst.tclassid = itag;
1362 #endif
1363 rth->dst.output = ip_rt_bug;
1364
1365 rth->rt_genid = rt_genid(dev_net(dev));
1366 rth->rt_flags = RTCF_MULTICAST;
1367 rth->rt_type = RTN_MULTICAST;
1368 rth->rt_is_input= 1;
1369 rth->rt_iif = 0;
1370 rth->rt_pmtu = 0;
1371 rth->rt_gateway = 0;
1372 rth->rt_uses_gateway = 0;
1373 INIT_LIST_HEAD(&rth->rt_uncached);
1374 if (our) {
1375 rth->dst.input= ip_local_deliver;
1376 rth->rt_flags |= RTCF_LOCAL;
1377 }
1378
1379 #ifdef CONFIG_IP_MROUTE
1380 if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev))
1381 rth->dst.input = ip_mr_input;
1382 #endif
1383 RT_CACHE_STAT_INC(in_slow_mc);
1384
1385 skb_dst_set(skb, &rth->dst);
1386 return 0;
1387
1388 e_nobufs:
1389 return -ENOBUFS;
1390 e_inval:
1391 return -EINVAL;
1392 e_err:
1393 return err;
1394 }
1395
1396
1397 static void ip_handle_martian_source(struct net_device *dev,
1398 struct in_device *in_dev,
1399 struct sk_buff *skb,
1400 __be32 daddr,
1401 __be32 saddr)
1402 {
1403 RT_CACHE_STAT_INC(in_martian_src);
1404 #ifdef CONFIG_IP_ROUTE_VERBOSE
1405 if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) {
1406 /*
1407 * RFC1812 recommendation, if source is martian,
1408 * the only hint is MAC header.
1409 */
1410 pr_warn("martian source %pI4 from %pI4, on dev %s\n",
1411 &daddr, &saddr, dev->name);
1412 if (dev->hard_header_len && skb_mac_header_was_set(skb)) {
1413 print_hex_dump(KERN_WARNING, "ll header: ",
1414 DUMP_PREFIX_OFFSET, 16, 1,
1415 skb_mac_header(skb),
1416 dev->hard_header_len, true);
1417 }
1418 }
1419 #endif
1420 }
1421
1422 /* called in rcu_read_lock() section */
1423 static int __mkroute_input(struct sk_buff *skb,
1424 const struct fib_result *res,
1425 struct in_device *in_dev,
1426 __be32 daddr, __be32 saddr, u32 tos)
1427 {
1428 struct rtable *rth;
1429 int err;
1430 struct in_device *out_dev;
1431 unsigned int flags = 0;
1432 bool do_cache;
1433 u32 itag;
1434
1435 /* get a working reference to the output device */
1436 out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res));
1437 if (out_dev == NULL) {
1438 net_crit_ratelimited("Bug in ip_route_input_slow(). Please report.\n");
1439 return -EINVAL;
1440 }
1441
1442 err = fib_validate_source(skb, saddr, daddr, tos, FIB_RES_OIF(*res),
1443 in_dev->dev, in_dev, &itag);
1444 if (err < 0) {
1445 ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr,
1446 saddr);
1447
1448 goto cleanup;
1449 }
1450
1451 do_cache = res->fi && !itag;
1452 if (out_dev == in_dev && err && IN_DEV_TX_REDIRECTS(out_dev) &&
1453 (IN_DEV_SHARED_MEDIA(out_dev) ||
1454 inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res)))) {
1455 flags |= RTCF_DOREDIRECT;
1456 do_cache = false;
1457 }
1458
1459 if (skb->protocol != htons(ETH_P_IP)) {
1460 /* Not IP (i.e. ARP). Do not create route, if it is
1461 * invalid for proxy arp. DNAT routes are always valid.
1462 *
1463 * Proxy arp feature have been extended to allow, ARP
1464 * replies back to the same interface, to support
1465 * Private VLAN switch technologies. See arp.c.
1466 */
1467 if (out_dev == in_dev &&
1468 IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) {
1469 err = -EINVAL;
1470 goto cleanup;
1471 }
1472 }
1473
1474 if (do_cache) {
1475 rth = rcu_dereference(FIB_RES_NH(*res).nh_rth_input);
1476 if (rt_cache_valid(rth)) {
1477 skb_dst_set_noref(skb, &rth->dst);
1478 goto out;
1479 }
1480 }
1481
1482 rth = rt_dst_alloc(out_dev->dev,
1483 IN_DEV_CONF_GET(in_dev, NOPOLICY),
1484 IN_DEV_CONF_GET(out_dev, NOXFRM), do_cache);
1485 if (!rth) {
1486 err = -ENOBUFS;
1487 goto cleanup;
1488 }
1489
1490 rth->rt_genid = rt_genid(dev_net(rth->dst.dev));
1491 rth->rt_flags = flags;
1492 rth->rt_type = res->type;
1493 rth->rt_is_input = 1;
1494 rth->rt_iif = 0;
1495 rth->rt_pmtu = 0;
1496 rth->rt_gateway = 0;
1497 rth->rt_uses_gateway = 0;
1498 INIT_LIST_HEAD(&rth->rt_uncached);
1499
1500 rth->dst.input = ip_forward;
1501 rth->dst.output = ip_output;
1502
1503 rt_set_nexthop(rth, daddr, res, NULL, res->fi, res->type, itag);
1504 skb_dst_set(skb, &rth->dst);
1505 out:
1506 err = 0;
1507 cleanup:
1508 return err;
1509 }
1510
1511 static int ip_mkroute_input(struct sk_buff *skb,
1512 struct fib_result *res,
1513 const struct flowi4 *fl4,
1514 struct in_device *in_dev,
1515 __be32 daddr, __be32 saddr, u32 tos)
1516 {
1517 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1518 if (res->fi && res->fi->fib_nhs > 1)
1519 fib_select_multipath(res);
1520 #endif
1521
1522 /* create a routing cache entry */
1523 return __mkroute_input(skb, res, in_dev, daddr, saddr, tos);
1524 }
1525
1526 /*
1527 * NOTE. We drop all the packets that has local source
1528 * addresses, because every properly looped back packet
1529 * must have correct destination already attached by output routine.
1530 *
1531 * Such approach solves two big problems:
1532 * 1. Not simplex devices are handled properly.
1533 * 2. IP spoofing attempts are filtered with 100% of guarantee.
1534 * called with rcu_read_lock()
1535 */
1536
1537 static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1538 u8 tos, struct net_device *dev)
1539 {
1540 struct fib_result res;
1541 struct in_device *in_dev = __in_dev_get_rcu(dev);
1542 struct flowi4 fl4;
1543 unsigned int flags = 0;
1544 u32 itag = 0;
1545 struct rtable *rth;
1546 int err = -EINVAL;
1547 struct net *net = dev_net(dev);
1548 bool do_cache;
1549
1550 /* IP on this device is disabled. */
1551
1552 if (!in_dev)
1553 goto out;
1554
1555 /* Check for the most weird martians, which can be not detected
1556 by fib_lookup.
1557 */
1558
1559 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr))
1560 goto martian_source;
1561
1562 res.fi = NULL;
1563 if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0))
1564 goto brd_input;
1565
1566 /* Accept zero addresses only to limited broadcast;
1567 * I even do not know to fix it or not. Waiting for complains :-)
1568 */
1569 if (ipv4_is_zeronet(saddr))
1570 goto martian_source;
1571
1572 if (ipv4_is_zeronet(daddr))
1573 goto martian_destination;
1574
1575 if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev))) {
1576 if (ipv4_is_loopback(daddr))
1577 goto martian_destination;
1578
1579 if (ipv4_is_loopback(saddr))
1580 goto martian_source;
1581 }
1582
1583 /*
1584 * Now we are ready to route packet.
1585 */
1586 fl4.flowi4_oif = 0;
1587 fl4.flowi4_iif = dev->ifindex;
1588 fl4.flowi4_mark = skb->mark;
1589 fl4.flowi4_tos = tos;
1590 fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
1591 fl4.daddr = daddr;
1592 fl4.saddr = saddr;
1593 err = fib_lookup(net, &fl4, &res);
1594 if (err != 0)
1595 goto no_route;
1596
1597 RT_CACHE_STAT_INC(in_slow_tot);
1598
1599 if (res.type == RTN_BROADCAST)
1600 goto brd_input;
1601
1602 if (res.type == RTN_LOCAL) {
1603 err = fib_validate_source(skb, saddr, daddr, tos,
1604 net->loopback_dev->ifindex,
1605 dev, in_dev, &itag);
1606 if (err < 0)
1607 goto martian_source_keep_err;
1608 goto local_input;
1609 }
1610
1611 if (!IN_DEV_FORWARD(in_dev))
1612 goto no_route;
1613 if (res.type != RTN_UNICAST)
1614 goto martian_destination;
1615
1616 err = ip_mkroute_input(skb, &res, &fl4, in_dev, daddr, saddr, tos);
1617 out: return err;
1618
1619 brd_input:
1620 if (skb->protocol != htons(ETH_P_IP))
1621 goto e_inval;
1622
1623 if (!ipv4_is_zeronet(saddr)) {
1624 err = fib_validate_source(skb, saddr, 0, tos, 0, dev,
1625 in_dev, &itag);
1626 if (err < 0)
1627 goto martian_source_keep_err;
1628 }
1629 flags |= RTCF_BROADCAST;
1630 res.type = RTN_BROADCAST;
1631 RT_CACHE_STAT_INC(in_brd);
1632
1633 local_input:
1634 do_cache = false;
1635 if (res.fi) {
1636 if (!itag) {
1637 rth = rcu_dereference(FIB_RES_NH(res).nh_rth_input);
1638 if (rt_cache_valid(rth)) {
1639 skb_dst_set_noref(skb, &rth->dst);
1640 err = 0;
1641 goto out;
1642 }
1643 do_cache = true;
1644 }
1645 }
1646
1647 rth = rt_dst_alloc(net->loopback_dev,
1648 IN_DEV_CONF_GET(in_dev, NOPOLICY), false, do_cache);
1649 if (!rth)
1650 goto e_nobufs;
1651
1652 rth->dst.input= ip_local_deliver;
1653 rth->dst.output= ip_rt_bug;
1654 #ifdef CONFIG_IP_ROUTE_CLASSID
1655 rth->dst.tclassid = itag;
1656 #endif
1657
1658 rth->rt_genid = rt_genid(net);
1659 rth->rt_flags = flags|RTCF_LOCAL;
1660 rth->rt_type = res.type;
1661 rth->rt_is_input = 1;
1662 rth->rt_iif = 0;
1663 rth->rt_pmtu = 0;
1664 rth->rt_gateway = 0;
1665 rth->rt_uses_gateway = 0;
1666 INIT_LIST_HEAD(&rth->rt_uncached);
1667 if (res.type == RTN_UNREACHABLE) {
1668 rth->dst.input= ip_error;
1669 rth->dst.error= -err;
1670 rth->rt_flags &= ~RTCF_LOCAL;
1671 }
1672 if (do_cache)
1673 rt_cache_route(&FIB_RES_NH(res), rth);
1674 skb_dst_set(skb, &rth->dst);
1675 err = 0;
1676 goto out;
1677
1678 no_route:
1679 RT_CACHE_STAT_INC(in_no_route);
1680 res.type = RTN_UNREACHABLE;
1681 if (err == -ESRCH)
1682 err = -ENETUNREACH;
1683 goto local_input;
1684
1685 /*
1686 * Do not cache martian addresses: they should be logged (RFC1812)
1687 */
1688 martian_destination:
1689 RT_CACHE_STAT_INC(in_martian_dst);
1690 #ifdef CONFIG_IP_ROUTE_VERBOSE
1691 if (IN_DEV_LOG_MARTIANS(in_dev))
1692 net_warn_ratelimited("martian destination %pI4 from %pI4, dev %s\n",
1693 &daddr, &saddr, dev->name);
1694 #endif
1695
1696 e_inval:
1697 err = -EINVAL;
1698 goto out;
1699
1700 e_nobufs:
1701 err = -ENOBUFS;
1702 goto out;
1703
1704 martian_source:
1705 err = -EINVAL;
1706 martian_source_keep_err:
1707 ip_handle_martian_source(dev, in_dev, skb, daddr, saddr);
1708 goto out;
1709 }
1710
1711 int ip_route_input_noref(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1712 u8 tos, struct net_device *dev)
1713 {
1714 int res;
1715
1716 rcu_read_lock();
1717
1718 /* Multicast recognition logic is moved from route cache to here.
1719 The problem was that too many Ethernet cards have broken/missing
1720 hardware multicast filters :-( As result the host on multicasting
1721 network acquires a lot of useless route cache entries, sort of
1722 SDR messages from all the world. Now we try to get rid of them.
1723 Really, provided software IP multicast filter is organized
1724 reasonably (at least, hashed), it does not result in a slowdown
1725 comparing with route cache reject entries.
1726 Note, that multicast routers are not affected, because
1727 route cache entry is created eventually.
1728 */
1729 if (ipv4_is_multicast(daddr)) {
1730 struct in_device *in_dev = __in_dev_get_rcu(dev);
1731
1732 if (in_dev) {
1733 int our = ip_check_mc_rcu(in_dev, daddr, saddr,
1734 ip_hdr(skb)->protocol);
1735 if (our
1736 #ifdef CONFIG_IP_MROUTE
1737 ||
1738 (!ipv4_is_local_multicast(daddr) &&
1739 IN_DEV_MFORWARD(in_dev))
1740 #endif
1741 ) {
1742 int res = ip_route_input_mc(skb, daddr, saddr,
1743 tos, dev, our);
1744 rcu_read_unlock();
1745 return res;
1746 }
1747 }
1748 rcu_read_unlock();
1749 return -EINVAL;
1750 }
1751 res = ip_route_input_slow(skb, daddr, saddr, tos, dev);
1752 rcu_read_unlock();
1753 return res;
1754 }
1755 EXPORT_SYMBOL(ip_route_input_noref);
1756
1757 /* called with rcu_read_lock() */
1758 static struct rtable *__mkroute_output(const struct fib_result *res,
1759 const struct flowi4 *fl4, int orig_oif,
1760 struct net_device *dev_out,
1761 unsigned int flags)
1762 {
1763 struct fib_info *fi = res->fi;
1764 struct fib_nh_exception *fnhe;
1765 struct in_device *in_dev;
1766 u16 type = res->type;
1767 struct rtable *rth;
1768 bool do_cache;
1769
1770 in_dev = __in_dev_get_rcu(dev_out);
1771 if (!in_dev)
1772 return ERR_PTR(-EINVAL);
1773
1774 if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev)))
1775 if (ipv4_is_loopback(fl4->saddr) && !(dev_out->flags & IFF_LOOPBACK))
1776 return ERR_PTR(-EINVAL);
1777
1778 if (ipv4_is_lbcast(fl4->daddr))
1779 type = RTN_BROADCAST;
1780 else if (ipv4_is_multicast(fl4->daddr))
1781 type = RTN_MULTICAST;
1782 else if (ipv4_is_zeronet(fl4->daddr))
1783 return ERR_PTR(-EINVAL);
1784
1785 if (dev_out->flags & IFF_LOOPBACK)
1786 flags |= RTCF_LOCAL;
1787
1788 if (type == RTN_BROADCAST) {
1789 flags |= RTCF_BROADCAST | RTCF_LOCAL;
1790 fi = NULL;
1791 } else if (type == RTN_MULTICAST) {
1792 flags |= RTCF_MULTICAST | RTCF_LOCAL;
1793 if (!ip_check_mc_rcu(in_dev, fl4->daddr, fl4->saddr,
1794 fl4->flowi4_proto))
1795 flags &= ~RTCF_LOCAL;
1796 /* If multicast route do not exist use
1797 * default one, but do not gateway in this case.
1798 * Yes, it is hack.
1799 */
1800 if (fi && res->prefixlen < 4)
1801 fi = NULL;
1802 }
1803
1804 fnhe = NULL;
1805 do_cache = fi != NULL;
1806 if (fi) {
1807 struct rtable __rcu **prth;
1808 struct fib_nh *nh = &FIB_RES_NH(*res);
1809
1810 fnhe = find_exception(nh, fl4->daddr);
1811 if (fnhe)
1812 prth = &fnhe->fnhe_rth;
1813 else {
1814 if (unlikely(fl4->flowi4_flags &
1815 FLOWI_FLAG_KNOWN_NH &&
1816 !(nh->nh_gw &&
1817 nh->nh_scope == RT_SCOPE_LINK))) {
1818 do_cache = false;
1819 goto add;
1820 }
1821 prth = __this_cpu_ptr(nh->nh_pcpu_rth_output);
1822 }
1823 rth = rcu_dereference(*prth);
1824 if (rt_cache_valid(rth)) {
1825 dst_hold(&rth->dst);
1826 return rth;
1827 }
1828 }
1829
1830 add:
1831 rth = rt_dst_alloc(dev_out,
1832 IN_DEV_CONF_GET(in_dev, NOPOLICY),
1833 IN_DEV_CONF_GET(in_dev, NOXFRM),
1834 do_cache);
1835 if (!rth)
1836 return ERR_PTR(-ENOBUFS);
1837
1838 rth->dst.output = ip_output;
1839
1840 rth->rt_genid = rt_genid(dev_net(dev_out));
1841 rth->rt_flags = flags;
1842 rth->rt_type = type;
1843 rth->rt_is_input = 0;
1844 rth->rt_iif = orig_oif ? : 0;
1845 rth->rt_pmtu = 0;
1846 rth->rt_gateway = 0;
1847 rth->rt_uses_gateway = 0;
1848 INIT_LIST_HEAD(&rth->rt_uncached);
1849
1850 RT_CACHE_STAT_INC(out_slow_tot);
1851
1852 if (flags & RTCF_LOCAL)
1853 rth->dst.input = ip_local_deliver;
1854 if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) {
1855 if (flags & RTCF_LOCAL &&
1856 !(dev_out->flags & IFF_LOOPBACK)) {
1857 rth->dst.output = ip_mc_output;
1858 RT_CACHE_STAT_INC(out_slow_mc);
1859 }
1860 #ifdef CONFIG_IP_MROUTE
1861 if (type == RTN_MULTICAST) {
1862 if (IN_DEV_MFORWARD(in_dev) &&
1863 !ipv4_is_local_multicast(fl4->daddr)) {
1864 rth->dst.input = ip_mr_input;
1865 rth->dst.output = ip_mc_output;
1866 }
1867 }
1868 #endif
1869 }
1870
1871 rt_set_nexthop(rth, fl4->daddr, res, fnhe, fi, type, 0);
1872
1873 return rth;
1874 }
1875
1876 /*
1877 * Major route resolver routine.
1878 */
1879
1880 struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *fl4)
1881 {
1882 struct net_device *dev_out = NULL;
1883 __u8 tos = RT_FL_TOS(fl4);
1884 unsigned int flags = 0;
1885 struct fib_result res;
1886 struct rtable *rth;
1887 int orig_oif;
1888
1889 res.tclassid = 0;
1890 res.fi = NULL;
1891 res.table = NULL;
1892
1893 orig_oif = fl4->flowi4_oif;
1894
1895 fl4->flowi4_iif = net->loopback_dev->ifindex;
1896 fl4->flowi4_tos = tos & IPTOS_RT_MASK;
1897 fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
1898 RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
1899
1900 rcu_read_lock();
1901 if (fl4->saddr) {
1902 rth = ERR_PTR(-EINVAL);
1903 if (ipv4_is_multicast(fl4->saddr) ||
1904 ipv4_is_lbcast(fl4->saddr) ||
1905 ipv4_is_zeronet(fl4->saddr))
1906 goto out;
1907
1908 /* I removed check for oif == dev_out->oif here.
1909 It was wrong for two reasons:
1910 1. ip_dev_find(net, saddr) can return wrong iface, if saddr
1911 is assigned to multiple interfaces.
1912 2. Moreover, we are allowed to send packets with saddr
1913 of another iface. --ANK
1914 */
1915
1916 if (fl4->flowi4_oif == 0 &&
1917 (ipv4_is_multicast(fl4->daddr) ||
1918 ipv4_is_lbcast(fl4->daddr))) {
1919 /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
1920 dev_out = __ip_dev_find(net, fl4->saddr, false);
1921 if (dev_out == NULL)
1922 goto out;
1923
1924 /* Special hack: user can direct multicasts
1925 and limited broadcast via necessary interface
1926 without fiddling with IP_MULTICAST_IF or IP_PKTINFO.
1927 This hack is not just for fun, it allows
1928 vic,vat and friends to work.
1929 They bind socket to loopback, set ttl to zero
1930 and expect that it will work.
1931 From the viewpoint of routing cache they are broken,
1932 because we are not allowed to build multicast path
1933 with loopback source addr (look, routing cache
1934 cannot know, that ttl is zero, so that packet
1935 will not leave this host and route is valid).
1936 Luckily, this hack is good workaround.
1937 */
1938
1939 fl4->flowi4_oif = dev_out->ifindex;
1940 goto make_route;
1941 }
1942
1943 if (!(fl4->flowi4_flags & FLOWI_FLAG_ANYSRC)) {
1944 /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
1945 if (!__ip_dev_find(net, fl4->saddr, false))
1946 goto out;
1947 }
1948 }
1949
1950
1951 if (fl4->flowi4_oif) {
1952 dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif);
1953 rth = ERR_PTR(-ENODEV);
1954 if (dev_out == NULL)
1955 goto out;
1956
1957 /* RACE: Check return value of inet_select_addr instead. */
1958 if (!(dev_out->flags & IFF_UP) || !__in_dev_get_rcu(dev_out)) {
1959 rth = ERR_PTR(-ENETUNREACH);
1960 goto out;
1961 }
1962 if (ipv4_is_local_multicast(fl4->daddr) ||
1963 ipv4_is_lbcast(fl4->daddr)) {
1964 if (!fl4->saddr)
1965 fl4->saddr = inet_select_addr(dev_out, 0,
1966 RT_SCOPE_LINK);
1967 goto make_route;
1968 }
1969 if (fl4->saddr) {
1970 if (ipv4_is_multicast(fl4->daddr))
1971 fl4->saddr = inet_select_addr(dev_out, 0,
1972 fl4->flowi4_scope);
1973 else if (!fl4->daddr)
1974 fl4->saddr = inet_select_addr(dev_out, 0,
1975 RT_SCOPE_HOST);
1976 }
1977 }
1978
1979 if (!fl4->daddr) {
1980 fl4->daddr = fl4->saddr;
1981 if (!fl4->daddr)
1982 fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK);
1983 dev_out = net->loopback_dev;
1984 fl4->flowi4_oif = net->loopback_dev->ifindex;
1985 res.type = RTN_LOCAL;
1986 flags |= RTCF_LOCAL;
1987 goto make_route;
1988 }
1989
1990 if (fib_lookup(net, fl4, &res)) {
1991 res.fi = NULL;
1992 res.table = NULL;
1993 if (fl4->flowi4_oif) {
1994 /* Apparently, routing tables are wrong. Assume,
1995 that the destination is on link.
1996
1997 WHY? DW.
1998 Because we are allowed to send to iface
1999 even if it has NO routes and NO assigned
2000 addresses. When oif is specified, routing
2001 tables are looked up with only one purpose:
2002 to catch if destination is gatewayed, rather than
2003 direct. Moreover, if MSG_DONTROUTE is set,
2004 we send packet, ignoring both routing tables
2005 and ifaddr state. --ANK
2006
2007
2008 We could make it even if oif is unknown,
2009 likely IPv6, but we do not.
2010 */
2011
2012 if (fl4->saddr == 0)
2013 fl4->saddr = inet_select_addr(dev_out, 0,
2014 RT_SCOPE_LINK);
2015 res.type = RTN_UNICAST;
2016 goto make_route;
2017 }
2018 rth = ERR_PTR(-ENETUNREACH);
2019 goto out;
2020 }
2021
2022 if (res.type == RTN_LOCAL) {
2023 if (!fl4->saddr) {
2024 if (res.fi->fib_prefsrc)
2025 fl4->saddr = res.fi->fib_prefsrc;
2026 else
2027 fl4->saddr = fl4->daddr;
2028 }
2029 dev_out = net->loopback_dev;
2030 fl4->flowi4_oif = dev_out->ifindex;
2031 flags |= RTCF_LOCAL;
2032 goto make_route;
2033 }
2034
2035 #ifdef CONFIG_IP_ROUTE_MULTIPATH
2036 if (res.fi->fib_nhs > 1 && fl4->flowi4_oif == 0)
2037 fib_select_multipath(&res);
2038 else
2039 #endif
2040 if (!res.prefixlen &&
2041 res.table->tb_num_default > 1 &&
2042 res.type == RTN_UNICAST && !fl4->flowi4_oif)
2043 fib_select_default(&res);
2044
2045 if (!fl4->saddr)
2046 fl4->saddr = FIB_RES_PREFSRC(net, res);
2047
2048 dev_out = FIB_RES_DEV(res);
2049 fl4->flowi4_oif = dev_out->ifindex;
2050
2051
2052 make_route:
2053 rth = __mkroute_output(&res, fl4, orig_oif, dev_out, flags);
2054
2055 out:
2056 rcu_read_unlock();
2057 return rth;
2058 }
2059 EXPORT_SYMBOL_GPL(__ip_route_output_key);
2060
2061 static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie)
2062 {
2063 return NULL;
2064 }
2065
2066 static unsigned int ipv4_blackhole_mtu(const struct dst_entry *dst)
2067 {
2068 unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
2069
2070 return mtu ? : dst->dev->mtu;
2071 }
2072
2073 static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
2074 struct sk_buff *skb, u32 mtu)
2075 {
2076 }
2077
2078 static void ipv4_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
2079 struct sk_buff *skb)
2080 {
2081 }
2082
2083 static u32 *ipv4_rt_blackhole_cow_metrics(struct dst_entry *dst,
2084 unsigned long old)
2085 {
2086 return NULL;
2087 }
2088
2089 static struct dst_ops ipv4_dst_blackhole_ops = {
2090 .family = AF_INET,
2091 .protocol = cpu_to_be16(ETH_P_IP),
2092 .check = ipv4_blackhole_dst_check,
2093 .mtu = ipv4_blackhole_mtu,
2094 .default_advmss = ipv4_default_advmss,
2095 .update_pmtu = ipv4_rt_blackhole_update_pmtu,
2096 .redirect = ipv4_rt_blackhole_redirect,
2097 .cow_metrics = ipv4_rt_blackhole_cow_metrics,
2098 .neigh_lookup = ipv4_neigh_lookup,
2099 };
2100
2101 struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig)
2102 {
2103 struct rtable *ort = (struct rtable *) dst_orig;
2104 struct rtable *rt;
2105
2106 rt = dst_alloc(&ipv4_dst_blackhole_ops, NULL, 1, DST_OBSOLETE_NONE, 0);
2107 if (rt) {
2108 struct dst_entry *new = &rt->dst;
2109
2110 new->__use = 1;
2111 new->input = dst_discard;
2112 new->output = dst_discard;
2113
2114 new->dev = ort->dst.dev;
2115 if (new->dev)
2116 dev_hold(new->dev);
2117
2118 rt->rt_is_input = ort->rt_is_input;
2119 rt->rt_iif = ort->rt_iif;
2120 rt->rt_pmtu = ort->rt_pmtu;
2121
2122 rt->rt_genid = rt_genid(net);
2123 rt->rt_flags = ort->rt_flags;
2124 rt->rt_type = ort->rt_type;
2125 rt->rt_gateway = ort->rt_gateway;
2126 rt->rt_uses_gateway = ort->rt_uses_gateway;
2127
2128 INIT_LIST_HEAD(&rt->rt_uncached);
2129
2130 dst_free(new);
2131 }
2132
2133 dst_release(dst_orig);
2134
2135 return rt ? &rt->dst : ERR_PTR(-ENOMEM);
2136 }
2137
2138 struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4,
2139 struct sock *sk)
2140 {
2141 struct rtable *rt = __ip_route_output_key(net, flp4);
2142
2143 if (IS_ERR(rt))
2144 return rt;
2145
2146 if (flp4->flowi4_proto)
2147 rt = (struct rtable *) xfrm_lookup(net, &rt->dst,
2148 flowi4_to_flowi(flp4),
2149 sk, 0);
2150
2151 return rt;
2152 }
2153 EXPORT_SYMBOL_GPL(ip_route_output_flow);
2154
2155 static int rt_fill_info(struct net *net, __be32 dst, __be32 src,
2156 struct flowi4 *fl4, struct sk_buff *skb, u32 pid,
2157 u32 seq, int event, int nowait, unsigned int flags)
2158 {
2159 struct rtable *rt = skb_rtable(skb);
2160 struct rtmsg *r;
2161 struct nlmsghdr *nlh;
2162 unsigned long expires = 0;
2163 u32 error;
2164 u32 metrics[RTAX_MAX];
2165
2166 nlh = nlmsg_put(skb, pid, seq, event, sizeof(*r), flags);
2167 if (nlh == NULL)
2168 return -EMSGSIZE;
2169
2170 r = nlmsg_data(nlh);
2171 r->rtm_family = AF_INET;
2172 r->rtm_dst_len = 32;
2173 r->rtm_src_len = 0;
2174 r->rtm_tos = fl4->flowi4_tos;
2175 r->rtm_table = RT_TABLE_MAIN;
2176 if (nla_put_u32(skb, RTA_TABLE, RT_TABLE_MAIN))
2177 goto nla_put_failure;
2178 r->rtm_type = rt->rt_type;
2179 r->rtm_scope = RT_SCOPE_UNIVERSE;
2180 r->rtm_protocol = RTPROT_UNSPEC;
2181 r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
2182 if (rt->rt_flags & RTCF_NOTIFY)
2183 r->rtm_flags |= RTM_F_NOTIFY;
2184
2185 if (nla_put_be32(skb, RTA_DST, dst))
2186 goto nla_put_failure;
2187 if (src) {
2188 r->rtm_src_len = 32;
2189 if (nla_put_be32(skb, RTA_SRC, src))
2190 goto nla_put_failure;
2191 }
2192 if (rt->dst.dev &&
2193 nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
2194 goto nla_put_failure;
2195 #ifdef CONFIG_IP_ROUTE_CLASSID
2196 if (rt->dst.tclassid &&
2197 nla_put_u32(skb, RTA_FLOW, rt->dst.tclassid))
2198 goto nla_put_failure;
2199 #endif
2200 if (!rt_is_input_route(rt) &&
2201 fl4->saddr != src) {
2202 if (nla_put_be32(skb, RTA_PREFSRC, fl4->saddr))
2203 goto nla_put_failure;
2204 }
2205 if (rt->rt_uses_gateway &&
2206 nla_put_be32(skb, RTA_GATEWAY, rt->rt_gateway))
2207 goto nla_put_failure;
2208
2209 expires = rt->dst.expires;
2210 if (expires) {
2211 unsigned long now = jiffies;
2212
2213 if (time_before(now, expires))
2214 expires -= now;
2215 else
2216 expires = 0;
2217 }
2218
2219 memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
2220 if (rt->rt_pmtu && expires)
2221 metrics[RTAX_MTU - 1] = rt->rt_pmtu;
2222 if (rtnetlink_put_metrics(skb, metrics) < 0)
2223 goto nla_put_failure;
2224
2225 if (fl4->flowi4_mark &&
2226 nla_put_be32(skb, RTA_MARK, fl4->flowi4_mark))
2227 goto nla_put_failure;
2228
2229 error = rt->dst.error;
2230
2231 if (rt_is_input_route(rt)) {
2232 if (nla_put_u32(skb, RTA_IIF, rt->rt_iif))
2233 goto nla_put_failure;
2234 }
2235
2236 if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, error) < 0)
2237 goto nla_put_failure;
2238
2239 return nlmsg_end(skb, nlh);
2240
2241 nla_put_failure:
2242 nlmsg_cancel(skb, nlh);
2243 return -EMSGSIZE;
2244 }
2245
2246 static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, void *arg)
2247 {
2248 struct net *net = sock_net(in_skb->sk);
2249 struct rtmsg *rtm;
2250 struct nlattr *tb[RTA_MAX+1];
2251 struct rtable *rt = NULL;
2252 struct flowi4 fl4;
2253 __be32 dst = 0;
2254 __be32 src = 0;
2255 u32 iif;
2256 int err;
2257 int mark;
2258 struct sk_buff *skb;
2259
2260 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy);
2261 if (err < 0)
2262 goto errout;
2263
2264 rtm = nlmsg_data(nlh);
2265
2266 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2267 if (skb == NULL) {
2268 err = -ENOBUFS;
2269 goto errout;
2270 }
2271
2272 /* Reserve room for dummy headers, this skb can pass
2273 through good chunk of routing engine.
2274 */
2275 skb_reset_mac_header(skb);
2276 skb_reset_network_header(skb);
2277
2278 /* Bugfix: need to give ip_route_input enough of an IP header to not gag. */
2279 ip_hdr(skb)->protocol = IPPROTO_ICMP;
2280 skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr));
2281
2282 src = tb[RTA_SRC] ? nla_get_be32(tb[RTA_SRC]) : 0;
2283 dst = tb[RTA_DST] ? nla_get_be32(tb[RTA_DST]) : 0;
2284 iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0;
2285 mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0;
2286
2287 memset(&fl4, 0, sizeof(fl4));
2288 fl4.daddr = dst;
2289 fl4.saddr = src;
2290 fl4.flowi4_tos = rtm->rtm_tos;
2291 fl4.flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0;
2292 fl4.flowi4_mark = mark;
2293
2294 if (iif) {
2295 struct net_device *dev;
2296
2297 dev = __dev_get_by_index(net, iif);
2298 if (dev == NULL) {
2299 err = -ENODEV;
2300 goto errout_free;
2301 }
2302
2303 skb->protocol = htons(ETH_P_IP);
2304 skb->dev = dev;
2305 skb->mark = mark;
2306 local_bh_disable();
2307 err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev);
2308 local_bh_enable();
2309
2310 rt = skb_rtable(skb);
2311 if (err == 0 && rt->dst.error)
2312 err = -rt->dst.error;
2313 } else {
2314 rt = ip_route_output_key(net, &fl4);
2315
2316 err = 0;
2317 if (IS_ERR(rt))
2318 err = PTR_ERR(rt);
2319 }
2320
2321 if (err)
2322 goto errout_free;
2323
2324 skb_dst_set(skb, &rt->dst);
2325 if (rtm->rtm_flags & RTM_F_NOTIFY)
2326 rt->rt_flags |= RTCF_NOTIFY;
2327
2328 err = rt_fill_info(net, dst, src, &fl4, skb,
2329 NETLINK_CB(in_skb).pid, nlh->nlmsg_seq,
2330 RTM_NEWROUTE, 0, 0);
2331 if (err <= 0)
2332 goto errout_free;
2333
2334 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
2335 errout:
2336 return err;
2337
2338 errout_free:
2339 kfree_skb(skb);
2340 goto errout;
2341 }
2342
2343 int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb)
2344 {
2345 return skb->len;
2346 }
2347
2348 void ip_rt_multicast_event(struct in_device *in_dev)
2349 {
2350 rt_cache_flush(dev_net(in_dev->dev));
2351 }
2352
2353 #ifdef CONFIG_SYSCTL
2354 static int ipv4_sysctl_rtcache_flush(ctl_table *__ctl, int write,
2355 void __user *buffer,
2356 size_t *lenp, loff_t *ppos)
2357 {
2358 if (write) {
2359 rt_cache_flush((struct net *)__ctl->extra1);
2360 return 0;
2361 }
2362
2363 return -EINVAL;
2364 }
2365
2366 static ctl_table ipv4_route_table[] = {
2367 {
2368 .procname = "gc_thresh",
2369 .data = &ipv4_dst_ops.gc_thresh,
2370 .maxlen = sizeof(int),
2371 .mode = 0644,
2372 .proc_handler = proc_dointvec,
2373 },
2374 {
2375 .procname = "max_size",
2376 .data = &ip_rt_max_size,
2377 .maxlen = sizeof(int),
2378 .mode = 0644,
2379 .proc_handler = proc_dointvec,
2380 },
2381 {
2382 /* Deprecated. Use gc_min_interval_ms */
2383
2384 .procname = "gc_min_interval",
2385 .data = &ip_rt_gc_min_interval,
2386 .maxlen = sizeof(int),
2387 .mode = 0644,
2388 .proc_handler = proc_dointvec_jiffies,
2389 },
2390 {
2391 .procname = "gc_min_interval_ms",
2392 .data = &ip_rt_gc_min_interval,
2393 .maxlen = sizeof(int),
2394 .mode = 0644,
2395 .proc_handler = proc_dointvec_ms_jiffies,
2396 },
2397 {
2398 .procname = "gc_timeout",
2399 .data = &ip_rt_gc_timeout,
2400 .maxlen = sizeof(int),
2401 .mode = 0644,
2402 .proc_handler = proc_dointvec_jiffies,
2403 },
2404 {
2405 .procname = "gc_interval",
2406 .data = &ip_rt_gc_interval,
2407 .maxlen = sizeof(int),
2408 .mode = 0644,
2409 .proc_handler = proc_dointvec_jiffies,
2410 },
2411 {
2412 .procname = "redirect_load",
2413 .data = &ip_rt_redirect_load,
2414 .maxlen = sizeof(int),
2415 .mode = 0644,
2416 .proc_handler = proc_dointvec,
2417 },
2418 {
2419 .procname = "redirect_number",
2420 .data = &ip_rt_redirect_number,
2421 .maxlen = sizeof(int),
2422 .mode = 0644,
2423 .proc_handler = proc_dointvec,
2424 },
2425 {
2426 .procname = "redirect_silence",
2427 .data = &ip_rt_redirect_silence,
2428 .maxlen = sizeof(int),
2429 .mode = 0644,
2430 .proc_handler = proc_dointvec,
2431 },
2432 {
2433 .procname = "error_cost",
2434 .data = &ip_rt_error_cost,
2435 .maxlen = sizeof(int),
2436 .mode = 0644,
2437 .proc_handler = proc_dointvec,
2438 },
2439 {
2440 .procname = "error_burst",
2441 .data = &ip_rt_error_burst,
2442 .maxlen = sizeof(int),
2443 .mode = 0644,
2444 .proc_handler = proc_dointvec,
2445 },
2446 {
2447 .procname = "gc_elasticity",
2448 .data = &ip_rt_gc_elasticity,
2449 .maxlen = sizeof(int),
2450 .mode = 0644,
2451 .proc_handler = proc_dointvec,
2452 },
2453 {
2454 .procname = "mtu_expires",
2455 .data = &ip_rt_mtu_expires,
2456 .maxlen = sizeof(int),
2457 .mode = 0644,
2458 .proc_handler = proc_dointvec_jiffies,
2459 },
2460 {
2461 .procname = "min_pmtu",
2462 .data = &ip_rt_min_pmtu,
2463 .maxlen = sizeof(int),
2464 .mode = 0644,
2465 .proc_handler = proc_dointvec,
2466 },
2467 {
2468 .procname = "min_adv_mss",
2469 .data = &ip_rt_min_advmss,
2470 .maxlen = sizeof(int),
2471 .mode = 0644,
2472 .proc_handler = proc_dointvec,
2473 },
2474 { }
2475 };
2476
2477 static struct ctl_table ipv4_route_flush_table[] = {
2478 {
2479 .procname = "flush",
2480 .maxlen = sizeof(int),
2481 .mode = 0200,
2482 .proc_handler = ipv4_sysctl_rtcache_flush,
2483 },
2484 { },
2485 };
2486
2487 static __net_init int sysctl_route_net_init(struct net *net)
2488 {
2489 struct ctl_table *tbl;
2490
2491 tbl = ipv4_route_flush_table;
2492 if (!net_eq(net, &init_net)) {
2493 tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL);
2494 if (tbl == NULL)
2495 goto err_dup;
2496 }
2497 tbl[0].extra1 = net;
2498
2499 net->ipv4.route_hdr = register_net_sysctl(net, "net/ipv4/route", tbl);
2500 if (net->ipv4.route_hdr == NULL)
2501 goto err_reg;
2502 return 0;
2503
2504 err_reg:
2505 if (tbl != ipv4_route_flush_table)
2506 kfree(tbl);
2507 err_dup:
2508 return -ENOMEM;
2509 }
2510
2511 static __net_exit void sysctl_route_net_exit(struct net *net)
2512 {
2513 struct ctl_table *tbl;
2514
2515 tbl = net->ipv4.route_hdr->ctl_table_arg;
2516 unregister_net_sysctl_table(net->ipv4.route_hdr);
2517 BUG_ON(tbl == ipv4_route_flush_table);
2518 kfree(tbl);
2519 }
2520
2521 static __net_initdata struct pernet_operations sysctl_route_ops = {
2522 .init = sysctl_route_net_init,
2523 .exit = sysctl_route_net_exit,
2524 };
2525 #endif
2526
2527 static __net_init int rt_genid_init(struct net *net)
2528 {
2529 atomic_set(&net->rt_genid, 0);
2530 get_random_bytes(&net->ipv4.dev_addr_genid,
2531 sizeof(net->ipv4.dev_addr_genid));
2532 return 0;
2533 }
2534
2535 static __net_initdata struct pernet_operations rt_genid_ops = {
2536 .init = rt_genid_init,
2537 };
2538
2539 static int __net_init ipv4_inetpeer_init(struct net *net)
2540 {
2541 struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
2542
2543 if (!bp)
2544 return -ENOMEM;
2545 inet_peer_base_init(bp);
2546 net->ipv4.peers = bp;
2547 return 0;
2548 }
2549
2550 static void __net_exit ipv4_inetpeer_exit(struct net *net)
2551 {
2552 struct inet_peer_base *bp = net->ipv4.peers;
2553
2554 net->ipv4.peers = NULL;
2555 inetpeer_invalidate_tree(bp);
2556 kfree(bp);
2557 }
2558
2559 static __net_initdata struct pernet_operations ipv4_inetpeer_ops = {
2560 .init = ipv4_inetpeer_init,
2561 .exit = ipv4_inetpeer_exit,
2562 };
2563
2564 #ifdef CONFIG_IP_ROUTE_CLASSID
2565 struct ip_rt_acct __percpu *ip_rt_acct __read_mostly;
2566 #endif /* CONFIG_IP_ROUTE_CLASSID */
2567
2568 int __init ip_rt_init(void)
2569 {
2570 int rc = 0;
2571
2572 #ifdef CONFIG_IP_ROUTE_CLASSID
2573 ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct));
2574 if (!ip_rt_acct)
2575 panic("IP: failed to allocate ip_rt_acct\n");
2576 #endif
2577
2578 ipv4_dst_ops.kmem_cachep =
2579 kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0,
2580 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
2581
2582 ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep;
2583
2584 if (dst_entries_init(&ipv4_dst_ops) < 0)
2585 panic("IP: failed to allocate ipv4_dst_ops counter\n");
2586
2587 if (dst_entries_init(&ipv4_dst_blackhole_ops) < 0)
2588 panic("IP: failed to allocate ipv4_dst_blackhole_ops counter\n");
2589
2590 ipv4_dst_ops.gc_thresh = ~0;
2591 ip_rt_max_size = INT_MAX;
2592
2593 devinet_init();
2594 ip_fib_init();
2595
2596 if (ip_rt_proc_init())
2597 pr_err("Unable to create route proc files\n");
2598 #ifdef CONFIG_XFRM
2599 xfrm_init();
2600 xfrm4_init(ip_rt_max_size);
2601 #endif
2602 rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL, NULL);
2603
2604 #ifdef CONFIG_SYSCTL
2605 register_pernet_subsys(&sysctl_route_ops);
2606 #endif
2607 register_pernet_subsys(&rt_genid_ops);
2608 register_pernet_subsys(&ipv4_inetpeer_ops);
2609 return rc;
2610 }
2611
2612 #ifdef CONFIG_SYSCTL
2613 /*
2614 * We really need to sanitize the damn ipv4 init order, then all
2615 * this nonsense will go away.
2616 */
2617 void __init ip_static_sysctl_init(void)
2618 {
2619 register_net_sysctl(&init_net, "net/ipv4/route", ipv4_route_table);
2620 }
2621 #endif
Linux ARM platform port for MOXA ART SoC