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xfrm: Return dst directly from xfrm_lookup()
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / ipv4 / route.c
blob63d37004ee66a8d432f9c4831e8b380827ea2894
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 #include <linux/module.h>
66 #include <asm/uaccess.h>
67 #include <asm/system.h>
68 #include <linux/bitops.h>
69 #include <linux/types.h>
70 #include <linux/kernel.h>
71 #include <linux/mm.h>
72 #include <linux/bootmem.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/workqueue.h>
83 #include <linux/skbuff.h>
84 #include <linux/inetdevice.h>
85 #include <linux/igmp.h>
86 #include <linux/pkt_sched.h>
87 #include <linux/mroute.h>
88 #include <linux/netfilter_ipv4.h>
89 #include <linux/random.h>
90 #include <linux/jhash.h>
91 #include <linux/rcupdate.h>
92 #include <linux/times.h>
93 #include <linux/slab.h>
94 #include <net/dst.h>
95 #include <net/net_namespace.h>
96 #include <net/protocol.h>
97 #include <net/ip.h>
98 #include <net/route.h>
99 #include <net/inetpeer.h>
100 #include <net/sock.h>
101 #include <net/ip_fib.h>
102 #include <net/arp.h>
103 #include <net/tcp.h>
104 #include <net/icmp.h>
105 #include <net/xfrm.h>
106 #include <net/netevent.h>
107 #include <net/rtnetlink.h>
108 #ifdef CONFIG_SYSCTL
109 #include <linux/sysctl.h>
110 #endif
111
112 #define RT_FL_TOS(oldflp) \
113 ((u32)(oldflp->fl4_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 static int rt_chain_length_max __read_mostly = 20;
133
134 /*
135 * Interface to generic destination cache.
136 */
137
138 static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie);
139 static unsigned int ipv4_default_advmss(const struct dst_entry *dst);
140 static unsigned int ipv4_default_mtu(const struct dst_entry *dst);
141 static void ipv4_dst_destroy(struct dst_entry *dst);
142 static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst);
143 static void ipv4_link_failure(struct sk_buff *skb);
144 static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
145 static int rt_garbage_collect(struct dst_ops *ops);
146
147 static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
148 int how)
149 {
150 }
151
152 static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old)
153 {
154 struct rtable *rt = (struct rtable *) dst;
155 struct inet_peer *peer;
156 u32 *p = NULL;
157
158 if (!rt->peer)
159 rt_bind_peer(rt, 1);
160
161 peer = rt->peer;
162 if (peer) {
163 u32 *old_p = __DST_METRICS_PTR(old);
164 unsigned long prev, new;
165
166 p = peer->metrics;
167 if (inet_metrics_new(peer))
168 memcpy(p, old_p, sizeof(u32) * RTAX_MAX);
169
170 new = (unsigned long) p;
171 prev = cmpxchg(&dst->_metrics, old, new);
172
173 if (prev != old) {
174 p = __DST_METRICS_PTR(prev);
175 if (prev & DST_METRICS_READ_ONLY)
176 p = NULL;
177 } else {
178 if (rt->fi) {
179 fib_info_put(rt->fi);
180 rt->fi = NULL;
181 }
182 }
183 }
184 return p;
185 }
186
187 static struct dst_ops ipv4_dst_ops = {
188 .family = AF_INET,
189 .protocol = cpu_to_be16(ETH_P_IP),
190 .gc = rt_garbage_collect,
191 .check = ipv4_dst_check,
192 .default_advmss = ipv4_default_advmss,
193 .default_mtu = ipv4_default_mtu,
194 .cow_metrics = ipv4_cow_metrics,
195 .destroy = ipv4_dst_destroy,
196 .ifdown = ipv4_dst_ifdown,
197 .negative_advice = ipv4_negative_advice,
198 .link_failure = ipv4_link_failure,
199 .update_pmtu = ip_rt_update_pmtu,
200 .local_out = __ip_local_out,
201 };
202
203 #define ECN_OR_COST(class) TC_PRIO_##class
204
205 const __u8 ip_tos2prio[16] = {
206 TC_PRIO_BESTEFFORT,
207 ECN_OR_COST(FILLER),
208 TC_PRIO_BESTEFFORT,
209 ECN_OR_COST(BESTEFFORT),
210 TC_PRIO_BULK,
211 ECN_OR_COST(BULK),
212 TC_PRIO_BULK,
213 ECN_OR_COST(BULK),
214 TC_PRIO_INTERACTIVE,
215 ECN_OR_COST(INTERACTIVE),
216 TC_PRIO_INTERACTIVE,
217 ECN_OR_COST(INTERACTIVE),
218 TC_PRIO_INTERACTIVE_BULK,
219 ECN_OR_COST(INTERACTIVE_BULK),
220 TC_PRIO_INTERACTIVE_BULK,
221 ECN_OR_COST(INTERACTIVE_BULK)
222 };
223
224
225 /*
226 * Route cache.
227 */
228
229 /* The locking scheme is rather straight forward:
230 *
231 * 1) Read-Copy Update protects the buckets of the central route hash.
232 * 2) Only writers remove entries, and they hold the lock
233 * as they look at rtable reference counts.
234 * 3) Only readers acquire references to rtable entries,
235 * they do so with atomic increments and with the
236 * lock held.
237 */
238
239 struct rt_hash_bucket {
240 struct rtable __rcu *chain;
241 };
242
243 #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) || \
244 defined(CONFIG_PROVE_LOCKING)
245 /*
246 * Instead of using one spinlock for each rt_hash_bucket, we use a table of spinlocks
247 * The size of this table is a power of two and depends on the number of CPUS.
248 * (on lockdep we have a quite big spinlock_t, so keep the size down there)
249 */
250 #ifdef CONFIG_LOCKDEP
251 # define RT_HASH_LOCK_SZ 256
252 #else
253 # if NR_CPUS >= 32
254 # define RT_HASH_LOCK_SZ 4096
255 # elif NR_CPUS >= 16
256 # define RT_HASH_LOCK_SZ 2048
257 # elif NR_CPUS >= 8
258 # define RT_HASH_LOCK_SZ 1024
259 # elif NR_CPUS >= 4
260 # define RT_HASH_LOCK_SZ 512
261 # else
262 # define RT_HASH_LOCK_SZ 256
263 # endif
264 #endif
265
266 static spinlock_t *rt_hash_locks;
267 # define rt_hash_lock_addr(slot) &rt_hash_locks[(slot) & (RT_HASH_LOCK_SZ - 1)]
268
269 static __init void rt_hash_lock_init(void)
270 {
271 int i;
272
273 rt_hash_locks = kmalloc(sizeof(spinlock_t) * RT_HASH_LOCK_SZ,
274 GFP_KERNEL);
275 if (!rt_hash_locks)
276 panic("IP: failed to allocate rt_hash_locks\n");
277
278 for (i = 0; i < RT_HASH_LOCK_SZ; i++)
279 spin_lock_init(&rt_hash_locks[i]);
280 }
281 #else
282 # define rt_hash_lock_addr(slot) NULL
283
284 static inline void rt_hash_lock_init(void)
285 {
286 }
287 #endif
288
289 static struct rt_hash_bucket *rt_hash_table __read_mostly;
290 static unsigned rt_hash_mask __read_mostly;
291 static unsigned int rt_hash_log __read_mostly;
292
293 static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat);
294 #define RT_CACHE_STAT_INC(field) __this_cpu_inc(rt_cache_stat.field)
295
296 static inline unsigned int rt_hash(__be32 daddr, __be32 saddr, int idx,
297 int genid)
298 {
299 return jhash_3words((__force u32)daddr, (__force u32)saddr,
300 idx, genid)
301 & rt_hash_mask;
302 }
303
304 static inline int rt_genid(struct net *net)
305 {
306 return atomic_read(&net->ipv4.rt_genid);
307 }
308
309 #ifdef CONFIG_PROC_FS
310 struct rt_cache_iter_state {
311 struct seq_net_private p;
312 int bucket;
313 int genid;
314 };
315
316 static struct rtable *rt_cache_get_first(struct seq_file *seq)
317 {
318 struct rt_cache_iter_state *st = seq->private;
319 struct rtable *r = NULL;
320
321 for (st->bucket = rt_hash_mask; st->bucket >= 0; --st->bucket) {
322 if (!rcu_dereference_raw(rt_hash_table[st->bucket].chain))
323 continue;
324 rcu_read_lock_bh();
325 r = rcu_dereference_bh(rt_hash_table[st->bucket].chain);
326 while (r) {
327 if (dev_net(r->dst.dev) == seq_file_net(seq) &&
328 r->rt_genid == st->genid)
329 return r;
330 r = rcu_dereference_bh(r->dst.rt_next);
331 }
332 rcu_read_unlock_bh();
333 }
334 return r;
335 }
336
337 static struct rtable *__rt_cache_get_next(struct seq_file *seq,
338 struct rtable *r)
339 {
340 struct rt_cache_iter_state *st = seq->private;
341
342 r = rcu_dereference_bh(r->dst.rt_next);
343 while (!r) {
344 rcu_read_unlock_bh();
345 do {
346 if (--st->bucket < 0)
347 return NULL;
348 } while (!rcu_dereference_raw(rt_hash_table[st->bucket].chain));
349 rcu_read_lock_bh();
350 r = rcu_dereference_bh(rt_hash_table[st->bucket].chain);
351 }
352 return r;
353 }
354
355 static struct rtable *rt_cache_get_next(struct seq_file *seq,
356 struct rtable *r)
357 {
358 struct rt_cache_iter_state *st = seq->private;
359 while ((r = __rt_cache_get_next(seq, r)) != NULL) {
360 if (dev_net(r->dst.dev) != seq_file_net(seq))
361 continue;
362 if (r->rt_genid == st->genid)
363 break;
364 }
365 return r;
366 }
367
368 static struct rtable *rt_cache_get_idx(struct seq_file *seq, loff_t pos)
369 {
370 struct rtable *r = rt_cache_get_first(seq);
371
372 if (r)
373 while (pos && (r = rt_cache_get_next(seq, r)))
374 --pos;
375 return pos ? NULL : r;
376 }
377
378 static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
379 {
380 struct rt_cache_iter_state *st = seq->private;
381 if (*pos)
382 return rt_cache_get_idx(seq, *pos - 1);
383 st->genid = rt_genid(seq_file_net(seq));
384 return SEQ_START_TOKEN;
385 }
386
387 static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
388 {
389 struct rtable *r;
390
391 if (v == SEQ_START_TOKEN)
392 r = rt_cache_get_first(seq);
393 else
394 r = rt_cache_get_next(seq, v);
395 ++*pos;
396 return r;
397 }
398
399 static void rt_cache_seq_stop(struct seq_file *seq, void *v)
400 {
401 if (v && v != SEQ_START_TOKEN)
402 rcu_read_unlock_bh();
403 }
404
405 static int rt_cache_seq_show(struct seq_file *seq, void *v)
406 {
407 if (v == SEQ_START_TOKEN)
408 seq_printf(seq, "%-127s\n",
409 "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t"
410 "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t"
411 "HHUptod\tSpecDst");
412 else {
413 struct rtable *r = v;
414 int len;
415
416 seq_printf(seq, "%s\t%08X\t%08X\t%8X\t%d\t%u\t%d\t"
417 "%08X\t%d\t%u\t%u\t%02X\t%d\t%1d\t%08X%n",
418 r->dst.dev ? r->dst.dev->name : "*",
419 (__force u32)r->rt_dst,
420 (__force u32)r->rt_gateway,
421 r->rt_flags, atomic_read(&r->dst.__refcnt),
422 r->dst.__use, 0, (__force u32)r->rt_src,
423 dst_metric_advmss(&r->dst) + 40,
424 dst_metric(&r->dst, RTAX_WINDOW),
425 (int)((dst_metric(&r->dst, RTAX_RTT) >> 3) +
426 dst_metric(&r->dst, RTAX_RTTVAR)),
427 r->fl.fl4_tos,
428 r->dst.hh ? atomic_read(&r->dst.hh->hh_refcnt) : -1,
429 r->dst.hh ? (r->dst.hh->hh_output ==
430 dev_queue_xmit) : 0,
431 r->rt_spec_dst, &len);
432
433 seq_printf(seq, "%*s\n", 127 - len, "");
434 }
435 return 0;
436 }
437
438 static const struct seq_operations rt_cache_seq_ops = {
439 .start = rt_cache_seq_start,
440 .next = rt_cache_seq_next,
441 .stop = rt_cache_seq_stop,
442 .show = rt_cache_seq_show,
443 };
444
445 static int rt_cache_seq_open(struct inode *inode, struct file *file)
446 {
447 return seq_open_net(inode, file, &rt_cache_seq_ops,
448 sizeof(struct rt_cache_iter_state));
449 }
450
451 static const struct file_operations rt_cache_seq_fops = {
452 .owner = THIS_MODULE,
453 .open = rt_cache_seq_open,
454 .read = seq_read,
455 .llseek = seq_lseek,
456 .release = seq_release_net,
457 };
458
459
460 static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos)
461 {
462 int cpu;
463
464 if (*pos == 0)
465 return SEQ_START_TOKEN;
466
467 for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
468 if (!cpu_possible(cpu))
469 continue;
470 *pos = cpu+1;
471 return &per_cpu(rt_cache_stat, cpu);
472 }
473 return NULL;
474 }
475
476 static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos)
477 {
478 int cpu;
479
480 for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
481 if (!cpu_possible(cpu))
482 continue;
483 *pos = cpu+1;
484 return &per_cpu(rt_cache_stat, cpu);
485 }
486 return NULL;
487
488 }
489
490 static void rt_cpu_seq_stop(struct seq_file *seq, void *v)
491 {
492
493 }
494
495 static int rt_cpu_seq_show(struct seq_file *seq, void *v)
496 {
497 struct rt_cache_stat *st = v;
498
499 if (v == SEQ_START_TOKEN) {
500 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");
501 return 0;
502 }
503
504 seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x "
505 " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n",
506 dst_entries_get_slow(&ipv4_dst_ops),
507 st->in_hit,
508 st->in_slow_tot,
509 st->in_slow_mc,
510 st->in_no_route,
511 st->in_brd,
512 st->in_martian_dst,
513 st->in_martian_src,
514
515 st->out_hit,
516 st->out_slow_tot,
517 st->out_slow_mc,
518
519 st->gc_total,
520 st->gc_ignored,
521 st->gc_goal_miss,
522 st->gc_dst_overflow,
523 st->in_hlist_search,
524 st->out_hlist_search
525 );
526 return 0;
527 }
528
529 static const struct seq_operations rt_cpu_seq_ops = {
530 .start = rt_cpu_seq_start,
531 .next = rt_cpu_seq_next,
532 .stop = rt_cpu_seq_stop,
533 .show = rt_cpu_seq_show,
534 };
535
536
537 static int rt_cpu_seq_open(struct inode *inode, struct file *file)
538 {
539 return seq_open(file, &rt_cpu_seq_ops);
540 }
541
542 static const struct file_operations rt_cpu_seq_fops = {
543 .owner = THIS_MODULE,
544 .open = rt_cpu_seq_open,
545 .read = seq_read,
546 .llseek = seq_lseek,
547 .release = seq_release,
548 };
549
550 #ifdef CONFIG_IP_ROUTE_CLASSID
551 static int rt_acct_proc_show(struct seq_file *m, void *v)
552 {
553 struct ip_rt_acct *dst, *src;
554 unsigned int i, j;
555
556 dst = kcalloc(256, sizeof(struct ip_rt_acct), GFP_KERNEL);
557 if (!dst)
558 return -ENOMEM;
559
560 for_each_possible_cpu(i) {
561 src = (struct ip_rt_acct *)per_cpu_ptr(ip_rt_acct, i);
562 for (j = 0; j < 256; j++) {
563 dst[j].o_bytes += src[j].o_bytes;
564 dst[j].o_packets += src[j].o_packets;
565 dst[j].i_bytes += src[j].i_bytes;
566 dst[j].i_packets += src[j].i_packets;
567 }
568 }
569
570 seq_write(m, dst, 256 * sizeof(struct ip_rt_acct));
571 kfree(dst);
572 return 0;
573 }
574
575 static int rt_acct_proc_open(struct inode *inode, struct file *file)
576 {
577 return single_open(file, rt_acct_proc_show, NULL);
578 }
579
580 static const struct file_operations rt_acct_proc_fops = {
581 .owner = THIS_MODULE,
582 .open = rt_acct_proc_open,
583 .read = seq_read,
584 .llseek = seq_lseek,
585 .release = single_release,
586 };
587 #endif
588
589 static int __net_init ip_rt_do_proc_init(struct net *net)
590 {
591 struct proc_dir_entry *pde;
592
593 pde = proc_net_fops_create(net, "rt_cache", S_IRUGO,
594 &rt_cache_seq_fops);
595 if (!pde)
596 goto err1;
597
598 pde = proc_create("rt_cache", S_IRUGO,
599 net->proc_net_stat, &rt_cpu_seq_fops);
600 if (!pde)
601 goto err2;
602
603 #ifdef CONFIG_IP_ROUTE_CLASSID
604 pde = proc_create("rt_acct", 0, net->proc_net, &rt_acct_proc_fops);
605 if (!pde)
606 goto err3;
607 #endif
608 return 0;
609
610 #ifdef CONFIG_IP_ROUTE_CLASSID
611 err3:
612 remove_proc_entry("rt_cache", net->proc_net_stat);
613 #endif
614 err2:
615 remove_proc_entry("rt_cache", net->proc_net);
616 err1:
617 return -ENOMEM;
618 }
619
620 static void __net_exit ip_rt_do_proc_exit(struct net *net)
621 {
622 remove_proc_entry("rt_cache", net->proc_net_stat);
623 remove_proc_entry("rt_cache", net->proc_net);
624 #ifdef CONFIG_IP_ROUTE_CLASSID
625 remove_proc_entry("rt_acct", net->proc_net);
626 #endif
627 }
628
629 static struct pernet_operations ip_rt_proc_ops __net_initdata = {
630 .init = ip_rt_do_proc_init,
631 .exit = ip_rt_do_proc_exit,
632 };
633
634 static int __init ip_rt_proc_init(void)
635 {
636 return register_pernet_subsys(&ip_rt_proc_ops);
637 }
638
639 #else
640 static inline int ip_rt_proc_init(void)
641 {
642 return 0;
643 }
644 #endif /* CONFIG_PROC_FS */
645
646 static inline void rt_free(struct rtable *rt)
647 {
648 call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free);
649 }
650
651 static inline void rt_drop(struct rtable *rt)
652 {
653 ip_rt_put(rt);
654 call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free);
655 }
656
657 static inline int rt_fast_clean(struct rtable *rth)
658 {
659 /* Kill broadcast/multicast entries very aggresively, if they
660 collide in hash table with more useful entries */
661 return (rth->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) &&
662 rt_is_input_route(rth) && rth->dst.rt_next;
663 }
664
665 static inline int rt_valuable(struct rtable *rth)
666 {
667 return (rth->rt_flags & (RTCF_REDIRECTED | RTCF_NOTIFY)) ||
668 (rth->peer && rth->peer->pmtu_expires);
669 }
670
671 static int rt_may_expire(struct rtable *rth, unsigned long tmo1, unsigned long tmo2)
672 {
673 unsigned long age;
674 int ret = 0;
675
676 if (atomic_read(&rth->dst.__refcnt))
677 goto out;
678
679 age = jiffies - rth->dst.lastuse;
680 if ((age <= tmo1 && !rt_fast_clean(rth)) ||
681 (age <= tmo2 && rt_valuable(rth)))
682 goto out;
683 ret = 1;
684 out: return ret;
685 }
686
687 /* Bits of score are:
688 * 31: very valuable
689 * 30: not quite useless
690 * 29..0: usage counter
691 */
692 static inline u32 rt_score(struct rtable *rt)
693 {
694 u32 score = jiffies - rt->dst.lastuse;
695
696 score = ~score & ~(3<<30);
697
698 if (rt_valuable(rt))
699 score |= (1<<31);
700
701 if (rt_is_output_route(rt) ||
702 !(rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST|RTCF_LOCAL)))
703 score |= (1<<30);
704
705 return score;
706 }
707
708 static inline bool rt_caching(const struct net *net)
709 {
710 return net->ipv4.current_rt_cache_rebuild_count <=
711 net->ipv4.sysctl_rt_cache_rebuild_count;
712 }
713
714 static inline bool compare_hash_inputs(const struct flowi *fl1,
715 const struct flowi *fl2)
716 {
717 return ((((__force u32)fl1->fl4_dst ^ (__force u32)fl2->fl4_dst) |
718 ((__force u32)fl1->fl4_src ^ (__force u32)fl2->fl4_src) |
719 (fl1->iif ^ fl2->iif)) == 0);
720 }
721
722 static inline int compare_keys(struct flowi *fl1, struct flowi *fl2)
723 {
724 return (((__force u32)fl1->fl4_dst ^ (__force u32)fl2->fl4_dst) |
725 ((__force u32)fl1->fl4_src ^ (__force u32)fl2->fl4_src) |
726 (fl1->mark ^ fl2->mark) |
727 (*(u16 *)&fl1->fl4_tos ^ *(u16 *)&fl2->fl4_tos) |
728 (fl1->oif ^ fl2->oif) |
729 (fl1->iif ^ fl2->iif)) == 0;
730 }
731
732 static inline int compare_netns(struct rtable *rt1, struct rtable *rt2)
733 {
734 return net_eq(dev_net(rt1->dst.dev), dev_net(rt2->dst.dev));
735 }
736
737 static inline int rt_is_expired(struct rtable *rth)
738 {
739 return rth->rt_genid != rt_genid(dev_net(rth->dst.dev));
740 }
741
742 /*
743 * Perform a full scan of hash table and free all entries.
744 * Can be called by a softirq or a process.
745 * In the later case, we want to be reschedule if necessary
746 */
747 static void rt_do_flush(struct net *net, int process_context)
748 {
749 unsigned int i;
750 struct rtable *rth, *next;
751
752 for (i = 0; i <= rt_hash_mask; i++) {
753 struct rtable __rcu **pprev;
754 struct rtable *list;
755
756 if (process_context && need_resched())
757 cond_resched();
758 rth = rcu_dereference_raw(rt_hash_table[i].chain);
759 if (!rth)
760 continue;
761
762 spin_lock_bh(rt_hash_lock_addr(i));
763
764 list = NULL;
765 pprev = &rt_hash_table[i].chain;
766 rth = rcu_dereference_protected(*pprev,
767 lockdep_is_held(rt_hash_lock_addr(i)));
768
769 while (rth) {
770 next = rcu_dereference_protected(rth->dst.rt_next,
771 lockdep_is_held(rt_hash_lock_addr(i)));
772
773 if (!net ||
774 net_eq(dev_net(rth->dst.dev), net)) {
775 rcu_assign_pointer(*pprev, next);
776 rcu_assign_pointer(rth->dst.rt_next, list);
777 list = rth;
778 } else {
779 pprev = &rth->dst.rt_next;
780 }
781 rth = next;
782 }
783
784 spin_unlock_bh(rt_hash_lock_addr(i));
785
786 for (; list; list = next) {
787 next = rcu_dereference_protected(list->dst.rt_next, 1);
788 rt_free(list);
789 }
790 }
791 }
792
793 /*
794 * While freeing expired entries, we compute average chain length
795 * and standard deviation, using fixed-point arithmetic.
796 * This to have an estimation of rt_chain_length_max
797 * rt_chain_length_max = max(elasticity, AVG + 4*SD)
798 * We use 3 bits for frational part, and 29 (or 61) for magnitude.
799 */
800
801 #define FRACT_BITS 3
802 #define ONE (1UL << FRACT_BITS)
803
804 /*
805 * Given a hash chain and an item in this hash chain,
806 * find if a previous entry has the same hash_inputs
807 * (but differs on tos, mark or oif)
808 * Returns 0 if an alias is found.
809 * Returns ONE if rth has no alias before itself.
810 */
811 static int has_noalias(const struct rtable *head, const struct rtable *rth)
812 {
813 const struct rtable *aux = head;
814
815 while (aux != rth) {
816 if (compare_hash_inputs(&aux->fl, &rth->fl))
817 return 0;
818 aux = rcu_dereference_protected(aux->dst.rt_next, 1);
819 }
820 return ONE;
821 }
822
823 /*
824 * Pertubation of rt_genid by a small quantity [1..256]
825 * Using 8 bits of shuffling ensure we can call rt_cache_invalidate()
826 * many times (2^24) without giving recent rt_genid.
827 * Jenkins hash is strong enough that litle changes of rt_genid are OK.
828 */
829 static void rt_cache_invalidate(struct net *net)
830 {
831 unsigned char shuffle;
832
833 get_random_bytes(&shuffle, sizeof(shuffle));
834 atomic_add(shuffle + 1U, &net->ipv4.rt_genid);
835 }
836
837 /*
838 * delay < 0 : invalidate cache (fast : entries will be deleted later)
839 * delay >= 0 : invalidate & flush cache (can be long)
840 */
841 void rt_cache_flush(struct net *net, int delay)
842 {
843 rt_cache_invalidate(net);
844 if (delay >= 0)
845 rt_do_flush(net, !in_softirq());
846 }
847
848 /* Flush previous cache invalidated entries from the cache */
849 void rt_cache_flush_batch(struct net *net)
850 {
851 rt_do_flush(net, !in_softirq());
852 }
853
854 static void rt_emergency_hash_rebuild(struct net *net)
855 {
856 if (net_ratelimit())
857 printk(KERN_WARNING "Route hash chain too long!\n");
858 rt_cache_invalidate(net);
859 }
860
861 /*
862 Short description of GC goals.
863
864 We want to build algorithm, which will keep routing cache
865 at some equilibrium point, when number of aged off entries
866 is kept approximately equal to newly generated ones.
867
868 Current expiration strength is variable "expire".
869 We try to adjust it dynamically, so that if networking
870 is idle expires is large enough to keep enough of warm entries,
871 and when load increases it reduces to limit cache size.
872 */
873
874 static int rt_garbage_collect(struct dst_ops *ops)
875 {
876 static unsigned long expire = RT_GC_TIMEOUT;
877 static unsigned long last_gc;
878 static int rover;
879 static int equilibrium;
880 struct rtable *rth;
881 struct rtable __rcu **rthp;
882 unsigned long now = jiffies;
883 int goal;
884 int entries = dst_entries_get_fast(&ipv4_dst_ops);
885
886 /*
887 * Garbage collection is pretty expensive,
888 * do not make it too frequently.
889 */
890
891 RT_CACHE_STAT_INC(gc_total);
892
893 if (now - last_gc < ip_rt_gc_min_interval &&
894 entries < ip_rt_max_size) {
895 RT_CACHE_STAT_INC(gc_ignored);
896 goto out;
897 }
898
899 entries = dst_entries_get_slow(&ipv4_dst_ops);
900 /* Calculate number of entries, which we want to expire now. */
901 goal = entries - (ip_rt_gc_elasticity << rt_hash_log);
902 if (goal <= 0) {
903 if (equilibrium < ipv4_dst_ops.gc_thresh)
904 equilibrium = ipv4_dst_ops.gc_thresh;
905 goal = entries - equilibrium;
906 if (goal > 0) {
907 equilibrium += min_t(unsigned int, goal >> 1, rt_hash_mask + 1);
908 goal = entries - equilibrium;
909 }
910 } else {
911 /* We are in dangerous area. Try to reduce cache really
912 * aggressively.
913 */
914 goal = max_t(unsigned int, goal >> 1, rt_hash_mask + 1);
915 equilibrium = entries - goal;
916 }
917
918 if (now - last_gc >= ip_rt_gc_min_interval)
919 last_gc = now;
920
921 if (goal <= 0) {
922 equilibrium += goal;
923 goto work_done;
924 }
925
926 do {
927 int i, k;
928
929 for (i = rt_hash_mask, k = rover; i >= 0; i--) {
930 unsigned long tmo = expire;
931
932 k = (k + 1) & rt_hash_mask;
933 rthp = &rt_hash_table[k].chain;
934 spin_lock_bh(rt_hash_lock_addr(k));
935 while ((rth = rcu_dereference_protected(*rthp,
936 lockdep_is_held(rt_hash_lock_addr(k)))) != NULL) {
937 if (!rt_is_expired(rth) &&
938 !rt_may_expire(rth, tmo, expire)) {
939 tmo >>= 1;
940 rthp = &rth->dst.rt_next;
941 continue;
942 }
943 *rthp = rth->dst.rt_next;
944 rt_free(rth);
945 goal--;
946 }
947 spin_unlock_bh(rt_hash_lock_addr(k));
948 if (goal <= 0)
949 break;
950 }
951 rover = k;
952
953 if (goal <= 0)
954 goto work_done;
955
956 /* Goal is not achieved. We stop process if:
957
958 - if expire reduced to zero. Otherwise, expire is halfed.
959 - if table is not full.
960 - if we are called from interrupt.
961 - jiffies check is just fallback/debug loop breaker.
962 We will not spin here for long time in any case.
963 */
964
965 RT_CACHE_STAT_INC(gc_goal_miss);
966
967 if (expire == 0)
968 break;
969
970 expire >>= 1;
971 #if RT_CACHE_DEBUG >= 2
972 printk(KERN_DEBUG "expire>> %u %d %d %d\n", expire,
973 dst_entries_get_fast(&ipv4_dst_ops), goal, i);
974 #endif
975
976 if (dst_entries_get_fast(&ipv4_dst_ops) < ip_rt_max_size)
977 goto out;
978 } while (!in_softirq() && time_before_eq(jiffies, now));
979
980 if (dst_entries_get_fast(&ipv4_dst_ops) < ip_rt_max_size)
981 goto out;
982 if (dst_entries_get_slow(&ipv4_dst_ops) < ip_rt_max_size)
983 goto out;
984 if (net_ratelimit())
985 printk(KERN_WARNING "dst cache overflow\n");
986 RT_CACHE_STAT_INC(gc_dst_overflow);
987 return 1;
988
989 work_done:
990 expire += ip_rt_gc_min_interval;
991 if (expire > ip_rt_gc_timeout ||
992 dst_entries_get_fast(&ipv4_dst_ops) < ipv4_dst_ops.gc_thresh ||
993 dst_entries_get_slow(&ipv4_dst_ops) < ipv4_dst_ops.gc_thresh)
994 expire = ip_rt_gc_timeout;
995 #if RT_CACHE_DEBUG >= 2
996 printk(KERN_DEBUG "expire++ %u %d %d %d\n", expire,
997 dst_entries_get_fast(&ipv4_dst_ops), goal, rover);
998 #endif
999 out: return 0;
1000 }
1001
1002 /*
1003 * Returns number of entries in a hash chain that have different hash_inputs
1004 */
1005 static int slow_chain_length(const struct rtable *head)
1006 {
1007 int length = 0;
1008 const struct rtable *rth = head;
1009
1010 while (rth) {
1011 length += has_noalias(head, rth);
1012 rth = rcu_dereference_protected(rth->dst.rt_next, 1);
1013 }
1014 return length >> FRACT_BITS;
1015 }
1016
1017 static int rt_intern_hash(unsigned hash, struct rtable *rt,
1018 struct rtable **rp, struct sk_buff *skb, int ifindex)
1019 {
1020 struct rtable *rth, *cand;
1021 struct rtable __rcu **rthp, **candp;
1022 unsigned long now;
1023 u32 min_score;
1024 int chain_length;
1025 int attempts = !in_softirq();
1026
1027 restart:
1028 chain_length = 0;
1029 min_score = ~(u32)0;
1030 cand = NULL;
1031 candp = NULL;
1032 now = jiffies;
1033
1034 if (!rt_caching(dev_net(rt->dst.dev))) {
1035 /*
1036 * If we're not caching, just tell the caller we
1037 * were successful and don't touch the route. The
1038 * caller hold the sole reference to the cache entry, and
1039 * it will be released when the caller is done with it.
1040 * If we drop it here, the callers have no way to resolve routes
1041 * when we're not caching. Instead, just point *rp at rt, so
1042 * the caller gets a single use out of the route
1043 * Note that we do rt_free on this new route entry, so that
1044 * once its refcount hits zero, we are still able to reap it
1045 * (Thanks Alexey)
1046 * Note: To avoid expensive rcu stuff for this uncached dst,
1047 * we set DST_NOCACHE so that dst_release() can free dst without
1048 * waiting a grace period.
1049 */
1050
1051 rt->dst.flags |= DST_NOCACHE;
1052 if (rt->rt_type == RTN_UNICAST || rt_is_output_route(rt)) {
1053 int err = arp_bind_neighbour(&rt->dst);
1054 if (err) {
1055 if (net_ratelimit())
1056 printk(KERN_WARNING
1057 "Neighbour table failure & not caching routes.\n");
1058 ip_rt_put(rt);
1059 return err;
1060 }
1061 }
1062
1063 goto skip_hashing;
1064 }
1065
1066 rthp = &rt_hash_table[hash].chain;
1067
1068 spin_lock_bh(rt_hash_lock_addr(hash));
1069 while ((rth = rcu_dereference_protected(*rthp,
1070 lockdep_is_held(rt_hash_lock_addr(hash)))) != NULL) {
1071 if (rt_is_expired(rth)) {
1072 *rthp = rth->dst.rt_next;
1073 rt_free(rth);
1074 continue;
1075 }
1076 if (compare_keys(&rth->fl, &rt->fl) && compare_netns(rth, rt)) {
1077 /* Put it first */
1078 *rthp = rth->dst.rt_next;
1079 /*
1080 * Since lookup is lockfree, the deletion
1081 * must be visible to another weakly ordered CPU before
1082 * the insertion at the start of the hash chain.
1083 */
1084 rcu_assign_pointer(rth->dst.rt_next,
1085 rt_hash_table[hash].chain);
1086 /*
1087 * Since lookup is lockfree, the update writes
1088 * must be ordered for consistency on SMP.
1089 */
1090 rcu_assign_pointer(rt_hash_table[hash].chain, rth);
1091
1092 dst_use(&rth->dst, now);
1093 spin_unlock_bh(rt_hash_lock_addr(hash));
1094
1095 rt_drop(rt);
1096 if (rp)
1097 *rp = rth;
1098 else
1099 skb_dst_set(skb, &rth->dst);
1100 return 0;
1101 }
1102
1103 if (!atomic_read(&rth->dst.__refcnt)) {
1104 u32 score = rt_score(rth);
1105
1106 if (score <= min_score) {
1107 cand = rth;
1108 candp = rthp;
1109 min_score = score;
1110 }
1111 }
1112
1113 chain_length++;
1114
1115 rthp = &rth->dst.rt_next;
1116 }
1117
1118 if (cand) {
1119 /* ip_rt_gc_elasticity used to be average length of chain
1120 * length, when exceeded gc becomes really aggressive.
1121 *
1122 * The second limit is less certain. At the moment it allows
1123 * only 2 entries per bucket. We will see.
1124 */
1125 if (chain_length > ip_rt_gc_elasticity) {
1126 *candp = cand->dst.rt_next;
1127 rt_free(cand);
1128 }
1129 } else {
1130 if (chain_length > rt_chain_length_max &&
1131 slow_chain_length(rt_hash_table[hash].chain) > rt_chain_length_max) {
1132 struct net *net = dev_net(rt->dst.dev);
1133 int num = ++net->ipv4.current_rt_cache_rebuild_count;
1134 if (!rt_caching(net)) {
1135 printk(KERN_WARNING "%s: %d rebuilds is over limit, route caching disabled\n",
1136 rt->dst.dev->name, num);
1137 }
1138 rt_emergency_hash_rebuild(net);
1139 spin_unlock_bh(rt_hash_lock_addr(hash));
1140
1141 hash = rt_hash(rt->fl.fl4_dst, rt->fl.fl4_src,
1142 ifindex, rt_genid(net));
1143 goto restart;
1144 }
1145 }
1146
1147 /* Try to bind route to arp only if it is output
1148 route or unicast forwarding path.
1149 */
1150 if (rt->rt_type == RTN_UNICAST || rt_is_output_route(rt)) {
1151 int err = arp_bind_neighbour(&rt->dst);
1152 if (err) {
1153 spin_unlock_bh(rt_hash_lock_addr(hash));
1154
1155 if (err != -ENOBUFS) {
1156 rt_drop(rt);
1157 return err;
1158 }
1159
1160 /* Neighbour tables are full and nothing
1161 can be released. Try to shrink route cache,
1162 it is most likely it holds some neighbour records.
1163 */
1164 if (attempts-- > 0) {
1165 int saved_elasticity = ip_rt_gc_elasticity;
1166 int saved_int = ip_rt_gc_min_interval;
1167 ip_rt_gc_elasticity = 1;
1168 ip_rt_gc_min_interval = 0;
1169 rt_garbage_collect(&ipv4_dst_ops);
1170 ip_rt_gc_min_interval = saved_int;
1171 ip_rt_gc_elasticity = saved_elasticity;
1172 goto restart;
1173 }
1174
1175 if (net_ratelimit())
1176 printk(KERN_WARNING "ipv4: Neighbour table overflow.\n");
1177 rt_drop(rt);
1178 return -ENOBUFS;
1179 }
1180 }
1181
1182 rt->dst.rt_next = rt_hash_table[hash].chain;
1183
1184 #if RT_CACHE_DEBUG >= 2
1185 if (rt->dst.rt_next) {
1186 struct rtable *trt;
1187 printk(KERN_DEBUG "rt_cache @%02x: %pI4",
1188 hash, &rt->rt_dst);
1189 for (trt = rt->dst.rt_next; trt; trt = trt->dst.rt_next)
1190 printk(" . %pI4", &trt->rt_dst);
1191 printk("\n");
1192 }
1193 #endif
1194 /*
1195 * Since lookup is lockfree, we must make sure
1196 * previous writes to rt are comitted to memory
1197 * before making rt visible to other CPUS.
1198 */
1199 rcu_assign_pointer(rt_hash_table[hash].chain, rt);
1200
1201 spin_unlock_bh(rt_hash_lock_addr(hash));
1202
1203 skip_hashing:
1204 if (rp)
1205 *rp = rt;
1206 else
1207 skb_dst_set(skb, &rt->dst);
1208 return 0;
1209 }
1210
1211 static atomic_t __rt_peer_genid = ATOMIC_INIT(0);
1212
1213 static u32 rt_peer_genid(void)
1214 {
1215 return atomic_read(&__rt_peer_genid);
1216 }
1217
1218 void rt_bind_peer(struct rtable *rt, int create)
1219 {
1220 struct inet_peer *peer;
1221
1222 peer = inet_getpeer_v4(rt->rt_dst, create);
1223
1224 if (peer && cmpxchg(&rt->peer, NULL, peer) != NULL)
1225 inet_putpeer(peer);
1226 else
1227 rt->rt_peer_genid = rt_peer_genid();
1228 }
1229
1230 /*
1231 * Peer allocation may fail only in serious out-of-memory conditions. However
1232 * we still can generate some output.
1233 * Random ID selection looks a bit dangerous because we have no chances to
1234 * select ID being unique in a reasonable period of time.
1235 * But broken packet identifier may be better than no packet at all.
1236 */
1237 static void ip_select_fb_ident(struct iphdr *iph)
1238 {
1239 static DEFINE_SPINLOCK(ip_fb_id_lock);
1240 static u32 ip_fallback_id;
1241 u32 salt;
1242
1243 spin_lock_bh(&ip_fb_id_lock);
1244 salt = secure_ip_id((__force __be32)ip_fallback_id ^ iph->daddr);
1245 iph->id = htons(salt & 0xFFFF);
1246 ip_fallback_id = salt;
1247 spin_unlock_bh(&ip_fb_id_lock);
1248 }
1249
1250 void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more)
1251 {
1252 struct rtable *rt = (struct rtable *) dst;
1253
1254 if (rt) {
1255 if (rt->peer == NULL)
1256 rt_bind_peer(rt, 1);
1257
1258 /* If peer is attached to destination, it is never detached,
1259 so that we need not to grab a lock to dereference it.
1260 */
1261 if (rt->peer) {
1262 iph->id = htons(inet_getid(rt->peer, more));
1263 return;
1264 }
1265 } else
1266 printk(KERN_DEBUG "rt_bind_peer(0) @%p\n",
1267 __builtin_return_address(0));
1268
1269 ip_select_fb_ident(iph);
1270 }
1271 EXPORT_SYMBOL(__ip_select_ident);
1272
1273 static void rt_del(unsigned hash, struct rtable *rt)
1274 {
1275 struct rtable __rcu **rthp;
1276 struct rtable *aux;
1277
1278 rthp = &rt_hash_table[hash].chain;
1279 spin_lock_bh(rt_hash_lock_addr(hash));
1280 ip_rt_put(rt);
1281 while ((aux = rcu_dereference_protected(*rthp,
1282 lockdep_is_held(rt_hash_lock_addr(hash)))) != NULL) {
1283 if (aux == rt || rt_is_expired(aux)) {
1284 *rthp = aux->dst.rt_next;
1285 rt_free(aux);
1286 continue;
1287 }
1288 rthp = &aux->dst.rt_next;
1289 }
1290 spin_unlock_bh(rt_hash_lock_addr(hash));
1291 }
1292
1293 /* called in rcu_read_lock() section */
1294 void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw,
1295 __be32 saddr, struct net_device *dev)
1296 {
1297 struct in_device *in_dev = __in_dev_get_rcu(dev);
1298 struct inet_peer *peer;
1299 struct net *net;
1300
1301 if (!in_dev)
1302 return;
1303
1304 net = dev_net(dev);
1305 if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) ||
1306 ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) ||
1307 ipv4_is_zeronet(new_gw))
1308 goto reject_redirect;
1309
1310 if (!IN_DEV_SHARED_MEDIA(in_dev)) {
1311 if (!inet_addr_onlink(in_dev, new_gw, old_gw))
1312 goto reject_redirect;
1313 if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev))
1314 goto reject_redirect;
1315 } else {
1316 if (inet_addr_type(net, new_gw) != RTN_UNICAST)
1317 goto reject_redirect;
1318 }
1319
1320 peer = inet_getpeer_v4(daddr, 1);
1321 if (peer) {
1322 peer->redirect_learned.a4 = new_gw;
1323
1324 inet_putpeer(peer);
1325
1326 atomic_inc(&__rt_peer_genid);
1327 }
1328 return;
1329
1330 reject_redirect:
1331 #ifdef CONFIG_IP_ROUTE_VERBOSE
1332 if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit())
1333 printk(KERN_INFO "Redirect from %pI4 on %s about %pI4 ignored.\n"
1334 " Advised path = %pI4 -> %pI4\n",
1335 &old_gw, dev->name, &new_gw,
1336 &saddr, &daddr);
1337 #endif
1338 ;
1339 }
1340
1341 static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
1342 {
1343 struct rtable *rt = (struct rtable *)dst;
1344 struct dst_entry *ret = dst;
1345
1346 if (rt) {
1347 if (dst->obsolete > 0) {
1348 ip_rt_put(rt);
1349 ret = NULL;
1350 } else if (rt->rt_flags & RTCF_REDIRECTED) {
1351 unsigned hash = rt_hash(rt->fl.fl4_dst, rt->fl.fl4_src,
1352 rt->fl.oif,
1353 rt_genid(dev_net(dst->dev)));
1354 #if RT_CACHE_DEBUG >= 1
1355 printk(KERN_DEBUG "ipv4_negative_advice: redirect to %pI4/%02x dropped\n",
1356 &rt->rt_dst, rt->fl.fl4_tos);
1357 #endif
1358 rt_del(hash, rt);
1359 ret = NULL;
1360 } else if (rt->peer &&
1361 rt->peer->pmtu_expires &&
1362 time_after_eq(jiffies, rt->peer->pmtu_expires)) {
1363 unsigned long orig = rt->peer->pmtu_expires;
1364
1365 if (cmpxchg(&rt->peer->pmtu_expires, orig, 0) == orig)
1366 dst_metric_set(dst, RTAX_MTU,
1367 rt->peer->pmtu_orig);
1368 }
1369 }
1370 return ret;
1371 }
1372
1373 /*
1374 * Algorithm:
1375 * 1. The first ip_rt_redirect_number redirects are sent
1376 * with exponential backoff, then we stop sending them at all,
1377 * assuming that the host ignores our redirects.
1378 * 2. If we did not see packets requiring redirects
1379 * during ip_rt_redirect_silence, we assume that the host
1380 * forgot redirected route and start to send redirects again.
1381 *
1382 * This algorithm is much cheaper and more intelligent than dumb load limiting
1383 * in icmp.c.
1384 *
1385 * NOTE. Do not forget to inhibit load limiting for redirects (redundant)
1386 * and "frag. need" (breaks PMTU discovery) in icmp.c.
1387 */
1388
1389 void ip_rt_send_redirect(struct sk_buff *skb)
1390 {
1391 struct rtable *rt = skb_rtable(skb);
1392 struct in_device *in_dev;
1393 struct inet_peer *peer;
1394 int log_martians;
1395
1396 rcu_read_lock();
1397 in_dev = __in_dev_get_rcu(rt->dst.dev);
1398 if (!in_dev || !IN_DEV_TX_REDIRECTS(in_dev)) {
1399 rcu_read_unlock();
1400 return;
1401 }
1402 log_martians = IN_DEV_LOG_MARTIANS(in_dev);
1403 rcu_read_unlock();
1404
1405 if (!rt->peer)
1406 rt_bind_peer(rt, 1);
1407 peer = rt->peer;
1408 if (!peer) {
1409 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway);
1410 return;
1411 }
1412
1413 /* No redirected packets during ip_rt_redirect_silence;
1414 * reset the algorithm.
1415 */
1416 if (time_after(jiffies, peer->rate_last + ip_rt_redirect_silence))
1417 peer->rate_tokens = 0;
1418
1419 /* Too many ignored redirects; do not send anything
1420 * set dst.rate_last to the last seen redirected packet.
1421 */
1422 if (peer->rate_tokens >= ip_rt_redirect_number) {
1423 peer->rate_last = jiffies;
1424 return;
1425 }
1426
1427 /* Check for load limit; set rate_last to the latest sent
1428 * redirect.
1429 */
1430 if (peer->rate_tokens == 0 ||
1431 time_after(jiffies,
1432 (peer->rate_last +
1433 (ip_rt_redirect_load << peer->rate_tokens)))) {
1434 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway);
1435 peer->rate_last = jiffies;
1436 ++peer->rate_tokens;
1437 #ifdef CONFIG_IP_ROUTE_VERBOSE
1438 if (log_martians &&
1439 peer->rate_tokens == ip_rt_redirect_number &&
1440 net_ratelimit())
1441 printk(KERN_WARNING "host %pI4/if%d ignores redirects for %pI4 to %pI4.\n",
1442 &rt->rt_src, rt->rt_iif,
1443 &rt->rt_dst, &rt->rt_gateway);
1444 #endif
1445 }
1446 }
1447
1448 static int ip_error(struct sk_buff *skb)
1449 {
1450 struct rtable *rt = skb_rtable(skb);
1451 struct inet_peer *peer;
1452 unsigned long now;
1453 bool send;
1454 int code;
1455
1456 switch (rt->dst.error) {
1457 case EINVAL:
1458 default:
1459 goto out;
1460 case EHOSTUNREACH:
1461 code = ICMP_HOST_UNREACH;
1462 break;
1463 case ENETUNREACH:
1464 code = ICMP_NET_UNREACH;
1465 IP_INC_STATS_BH(dev_net(rt->dst.dev),
1466 IPSTATS_MIB_INNOROUTES);
1467 break;
1468 case EACCES:
1469 code = ICMP_PKT_FILTERED;
1470 break;
1471 }
1472
1473 if (!rt->peer)
1474 rt_bind_peer(rt, 1);
1475 peer = rt->peer;
1476
1477 send = true;
1478 if (peer) {
1479 now = jiffies;
1480 peer->rate_tokens += now - peer->rate_last;
1481 if (peer->rate_tokens > ip_rt_error_burst)
1482 peer->rate_tokens = ip_rt_error_burst;
1483 peer->rate_last = now;
1484 if (peer->rate_tokens >= ip_rt_error_cost)
1485 peer->rate_tokens -= ip_rt_error_cost;
1486 else
1487 send = false;
1488 }
1489 if (send)
1490 icmp_send(skb, ICMP_DEST_UNREACH, code, 0);
1491
1492 out: kfree_skb(skb);
1493 return 0;
1494 }
1495
1496 /*
1497 * The last two values are not from the RFC but
1498 * are needed for AMPRnet AX.25 paths.
1499 */
1500
1501 static const unsigned short mtu_plateau[] =
1502 {32000, 17914, 8166, 4352, 2002, 1492, 576, 296, 216, 128 };
1503
1504 static inline unsigned short guess_mtu(unsigned short old_mtu)
1505 {
1506 int i;
1507
1508 for (i = 0; i < ARRAY_SIZE(mtu_plateau); i++)
1509 if (old_mtu > mtu_plateau[i])
1510 return mtu_plateau[i];
1511 return 68;
1512 }
1513
1514 unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph,
1515 unsigned short new_mtu,
1516 struct net_device *dev)
1517 {
1518 unsigned short old_mtu = ntohs(iph->tot_len);
1519 unsigned short est_mtu = 0;
1520 struct inet_peer *peer;
1521
1522 peer = inet_getpeer_v4(iph->daddr, 1);
1523 if (peer) {
1524 unsigned short mtu = new_mtu;
1525
1526 if (new_mtu < 68 || new_mtu >= old_mtu) {
1527 /* BSD 4.2 derived systems incorrectly adjust
1528 * tot_len by the IP header length, and report
1529 * a zero MTU in the ICMP message.
1530 */
1531 if (mtu == 0 &&
1532 old_mtu >= 68 + (iph->ihl << 2))
1533 old_mtu -= iph->ihl << 2;
1534 mtu = guess_mtu(old_mtu);
1535 }
1536
1537 if (mtu < ip_rt_min_pmtu)
1538 mtu = ip_rt_min_pmtu;
1539 if (!peer->pmtu_expires || mtu < peer->pmtu_learned) {
1540 est_mtu = mtu;
1541 peer->pmtu_learned = mtu;
1542 peer->pmtu_expires = jiffies + ip_rt_mtu_expires;
1543 }
1544
1545 inet_putpeer(peer);
1546
1547 atomic_inc(&__rt_peer_genid);
1548 }
1549 return est_mtu ? : new_mtu;
1550 }
1551
1552 static void check_peer_pmtu(struct dst_entry *dst, struct inet_peer *peer)
1553 {
1554 unsigned long expires = peer->pmtu_expires;
1555
1556 if (time_before(expires, jiffies)) {
1557 u32 orig_dst_mtu = dst_mtu(dst);
1558 if (peer->pmtu_learned < orig_dst_mtu) {
1559 if (!peer->pmtu_orig)
1560 peer->pmtu_orig = dst_metric_raw(dst, RTAX_MTU);
1561 dst_metric_set(dst, RTAX_MTU, peer->pmtu_learned);
1562 }
1563 } else if (cmpxchg(&peer->pmtu_expires, expires, 0) == expires)
1564 dst_metric_set(dst, RTAX_MTU, peer->pmtu_orig);
1565 }
1566
1567 static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
1568 {
1569 struct rtable *rt = (struct rtable *) dst;
1570 struct inet_peer *peer;
1571
1572 dst_confirm(dst);
1573
1574 if (!rt->peer)
1575 rt_bind_peer(rt, 1);
1576 peer = rt->peer;
1577 if (peer) {
1578 if (mtu < ip_rt_min_pmtu)
1579 mtu = ip_rt_min_pmtu;
1580 if (!peer->pmtu_expires || mtu < peer->pmtu_learned) {
1581 peer->pmtu_learned = mtu;
1582 peer->pmtu_expires = jiffies + ip_rt_mtu_expires;
1583
1584 atomic_inc(&__rt_peer_genid);
1585 rt->rt_peer_genid = rt_peer_genid();
1586
1587 check_peer_pmtu(dst, peer);
1588 }
1589 inet_putpeer(peer);
1590 }
1591 }
1592
1593 static int check_peer_redir(struct dst_entry *dst, struct inet_peer *peer)
1594 {
1595 struct rtable *rt = (struct rtable *) dst;
1596 __be32 orig_gw = rt->rt_gateway;
1597
1598 dst_confirm(&rt->dst);
1599
1600 neigh_release(rt->dst.neighbour);
1601 rt->dst.neighbour = NULL;
1602
1603 rt->rt_gateway = peer->redirect_learned.a4;
1604 if (arp_bind_neighbour(&rt->dst) ||
1605 !(rt->dst.neighbour->nud_state & NUD_VALID)) {
1606 if (rt->dst.neighbour)
1607 neigh_event_send(rt->dst.neighbour, NULL);
1608 rt->rt_gateway = orig_gw;
1609 return -EAGAIN;
1610 } else {
1611 rt->rt_flags |= RTCF_REDIRECTED;
1612 call_netevent_notifiers(NETEVENT_NEIGH_UPDATE,
1613 rt->dst.neighbour);
1614 }
1615 return 0;
1616 }
1617
1618 static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
1619 {
1620 struct rtable *rt = (struct rtable *) dst;
1621
1622 if (rt_is_expired(rt))
1623 return NULL;
1624 if (rt->rt_peer_genid != rt_peer_genid()) {
1625 struct inet_peer *peer;
1626
1627 if (!rt->peer)
1628 rt_bind_peer(rt, 0);
1629
1630 peer = rt->peer;
1631 if (peer && peer->pmtu_expires)
1632 check_peer_pmtu(dst, peer);
1633
1634 if (peer && peer->redirect_learned.a4 &&
1635 peer->redirect_learned.a4 != rt->rt_gateway) {
1636 if (check_peer_redir(dst, peer))
1637 return NULL;
1638 }
1639
1640 rt->rt_peer_genid = rt_peer_genid();
1641 }
1642 return dst;
1643 }
1644
1645 static void ipv4_dst_destroy(struct dst_entry *dst)
1646 {
1647 struct rtable *rt = (struct rtable *) dst;
1648 struct inet_peer *peer = rt->peer;
1649
1650 if (rt->fi) {
1651 fib_info_put(rt->fi);
1652 rt->fi = NULL;
1653 }
1654 if (peer) {
1655 rt->peer = NULL;
1656 inet_putpeer(peer);
1657 }
1658 }
1659
1660
1661 static void ipv4_link_failure(struct sk_buff *skb)
1662 {
1663 struct rtable *rt;
1664
1665 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
1666
1667 rt = skb_rtable(skb);
1668 if (rt &&
1669 rt->peer &&
1670 rt->peer->pmtu_expires) {
1671 unsigned long orig = rt->peer->pmtu_expires;
1672
1673 if (cmpxchg(&rt->peer->pmtu_expires, orig, 0) == orig)
1674 dst_metric_set(&rt->dst, RTAX_MTU, rt->peer->pmtu_orig);
1675 }
1676 }
1677
1678 static int ip_rt_bug(struct sk_buff *skb)
1679 {
1680 printk(KERN_DEBUG "ip_rt_bug: %pI4 -> %pI4, %s\n",
1681 &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr,
1682 skb->dev ? skb->dev->name : "?");
1683 kfree_skb(skb);
1684 return 0;
1685 }
1686
1687 /*
1688 We do not cache source address of outgoing interface,
1689 because it is used only by IP RR, TS and SRR options,
1690 so that it out of fast path.
1691
1692 BTW remember: "addr" is allowed to be not aligned
1693 in IP options!
1694 */
1695
1696 void ip_rt_get_source(u8 *addr, struct rtable *rt)
1697 {
1698 __be32 src;
1699 struct fib_result res;
1700
1701 if (rt_is_output_route(rt))
1702 src = rt->rt_src;
1703 else {
1704 rcu_read_lock();
1705 if (fib_lookup(dev_net(rt->dst.dev), &rt->fl, &res) == 0)
1706 src = FIB_RES_PREFSRC(res);
1707 else
1708 src = inet_select_addr(rt->dst.dev, rt->rt_gateway,
1709 RT_SCOPE_UNIVERSE);
1710 rcu_read_unlock();
1711 }
1712 memcpy(addr, &src, 4);
1713 }
1714
1715 #ifdef CONFIG_IP_ROUTE_CLASSID
1716 static void set_class_tag(struct rtable *rt, u32 tag)
1717 {
1718 if (!(rt->dst.tclassid & 0xFFFF))
1719 rt->dst.tclassid |= tag & 0xFFFF;
1720 if (!(rt->dst.tclassid & 0xFFFF0000))
1721 rt->dst.tclassid |= tag & 0xFFFF0000;
1722 }
1723 #endif
1724
1725 static unsigned int ipv4_default_advmss(const struct dst_entry *dst)
1726 {
1727 unsigned int advmss = dst_metric_raw(dst, RTAX_ADVMSS);
1728
1729 if (advmss == 0) {
1730 advmss = max_t(unsigned int, dst->dev->mtu - 40,
1731 ip_rt_min_advmss);
1732 if (advmss > 65535 - 40)
1733 advmss = 65535 - 40;
1734 }
1735 return advmss;
1736 }
1737
1738 static unsigned int ipv4_default_mtu(const struct dst_entry *dst)
1739 {
1740 unsigned int mtu = dst->dev->mtu;
1741
1742 if (unlikely(dst_metric_locked(dst, RTAX_MTU))) {
1743 const struct rtable *rt = (const struct rtable *) dst;
1744
1745 if (rt->rt_gateway != rt->rt_dst && mtu > 576)
1746 mtu = 576;
1747 }
1748
1749 if (mtu > IP_MAX_MTU)
1750 mtu = IP_MAX_MTU;
1751
1752 return mtu;
1753 }
1754
1755 static void rt_init_metrics(struct rtable *rt, struct fib_info *fi)
1756 {
1757 struct inet_peer *peer;
1758 int create = 0;
1759
1760 /* If a peer entry exists for this destination, we must hook
1761 * it up in order to get at cached metrics.
1762 */
1763 if (rt->fl.flags & FLOWI_FLAG_PRECOW_METRICS)
1764 create = 1;
1765
1766 rt_bind_peer(rt, create);
1767 peer = rt->peer;
1768 if (peer) {
1769 if (inet_metrics_new(peer))
1770 memcpy(peer->metrics, fi->fib_metrics,
1771 sizeof(u32) * RTAX_MAX);
1772 dst_init_metrics(&rt->dst, peer->metrics, false);
1773
1774 if (peer->pmtu_expires)
1775 check_peer_pmtu(&rt->dst, peer);
1776 if (peer->redirect_learned.a4 &&
1777 peer->redirect_learned.a4 != rt->rt_gateway) {
1778 rt->rt_gateway = peer->redirect_learned.a4;
1779 rt->rt_flags |= RTCF_REDIRECTED;
1780 }
1781 } else {
1782 if (fi->fib_metrics != (u32 *) dst_default_metrics) {
1783 rt->fi = fi;
1784 atomic_inc(&fi->fib_clntref);
1785 }
1786 dst_init_metrics(&rt->dst, fi->fib_metrics, true);
1787 }
1788 }
1789
1790 static void rt_set_nexthop(struct rtable *rt, const struct fib_result *res,
1791 struct fib_info *fi, u16 type, u32 itag)
1792 {
1793 struct dst_entry *dst = &rt->dst;
1794
1795 if (fi) {
1796 if (FIB_RES_GW(*res) &&
1797 FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
1798 rt->rt_gateway = FIB_RES_GW(*res);
1799 rt_init_metrics(rt, fi);
1800 #ifdef CONFIG_IP_ROUTE_CLASSID
1801 dst->tclassid = FIB_RES_NH(*res).nh_tclassid;
1802 #endif
1803 }
1804
1805 if (dst_mtu(dst) > IP_MAX_MTU)
1806 dst_metric_set(dst, RTAX_MTU, IP_MAX_MTU);
1807 if (dst_metric_raw(dst, RTAX_ADVMSS) > 65535 - 40)
1808 dst_metric_set(dst, RTAX_ADVMSS, 65535 - 40);
1809
1810 #ifdef CONFIG_IP_ROUTE_CLASSID
1811 #ifdef CONFIG_IP_MULTIPLE_TABLES
1812 set_class_tag(rt, fib_rules_tclass(res));
1813 #endif
1814 set_class_tag(rt, itag);
1815 #endif
1816 rt->rt_type = type;
1817 }
1818
1819 static struct rtable *rt_dst_alloc(bool nopolicy, bool noxfrm)
1820 {
1821 struct rtable *rt = dst_alloc(&ipv4_dst_ops, 1);
1822 if (rt) {
1823 rt->dst.obsolete = -1;
1824
1825 rt->dst.flags = DST_HOST |
1826 (nopolicy ? DST_NOPOLICY : 0) |
1827 (noxfrm ? DST_NOXFRM : 0);
1828 }
1829 return rt;
1830 }
1831
1832 /* called in rcu_read_lock() section */
1833 static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1834 u8 tos, struct net_device *dev, int our)
1835 {
1836 unsigned int hash;
1837 struct rtable *rth;
1838 __be32 spec_dst;
1839 struct in_device *in_dev = __in_dev_get_rcu(dev);
1840 u32 itag = 0;
1841 int err;
1842
1843 /* Primary sanity checks. */
1844
1845 if (in_dev == NULL)
1846 return -EINVAL;
1847
1848 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) ||
1849 ipv4_is_loopback(saddr) || skb->protocol != htons(ETH_P_IP))
1850 goto e_inval;
1851
1852 if (ipv4_is_zeronet(saddr)) {
1853 if (!ipv4_is_local_multicast(daddr))
1854 goto e_inval;
1855 spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK);
1856 } else {
1857 err = fib_validate_source(saddr, 0, tos, 0, dev, &spec_dst,
1858 &itag, 0);
1859 if (err < 0)
1860 goto e_err;
1861 }
1862 rth = rt_dst_alloc(IN_DEV_CONF_GET(in_dev, NOPOLICY), false);
1863 if (!rth)
1864 goto e_nobufs;
1865
1866 rth->dst.output = ip_rt_bug;
1867
1868 rth->fl.fl4_dst = daddr;
1869 rth->rt_dst = daddr;
1870 rth->fl.fl4_tos = tos;
1871 rth->fl.mark = skb->mark;
1872 rth->fl.fl4_src = saddr;
1873 rth->rt_src = saddr;
1874 #ifdef CONFIG_IP_ROUTE_CLASSID
1875 rth->dst.tclassid = itag;
1876 #endif
1877 rth->rt_iif =
1878 rth->fl.iif = dev->ifindex;
1879 rth->dst.dev = init_net.loopback_dev;
1880 dev_hold(rth->dst.dev);
1881 rth->fl.oif = 0;
1882 rth->rt_gateway = daddr;
1883 rth->rt_spec_dst= spec_dst;
1884 rth->rt_genid = rt_genid(dev_net(dev));
1885 rth->rt_flags = RTCF_MULTICAST;
1886 rth->rt_type = RTN_MULTICAST;
1887 if (our) {
1888 rth->dst.input= ip_local_deliver;
1889 rth->rt_flags |= RTCF_LOCAL;
1890 }
1891
1892 #ifdef CONFIG_IP_MROUTE
1893 if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev))
1894 rth->dst.input = ip_mr_input;
1895 #endif
1896 RT_CACHE_STAT_INC(in_slow_mc);
1897
1898 hash = rt_hash(daddr, saddr, dev->ifindex, rt_genid(dev_net(dev)));
1899 return rt_intern_hash(hash, rth, NULL, skb, dev->ifindex);
1900
1901 e_nobufs:
1902 return -ENOBUFS;
1903 e_inval:
1904 return -EINVAL;
1905 e_err:
1906 return err;
1907 }
1908
1909
1910 static void ip_handle_martian_source(struct net_device *dev,
1911 struct in_device *in_dev,
1912 struct sk_buff *skb,
1913 __be32 daddr,
1914 __be32 saddr)
1915 {
1916 RT_CACHE_STAT_INC(in_martian_src);
1917 #ifdef CONFIG_IP_ROUTE_VERBOSE
1918 if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) {
1919 /*
1920 * RFC1812 recommendation, if source is martian,
1921 * the only hint is MAC header.
1922 */
1923 printk(KERN_WARNING "martian source %pI4 from %pI4, on dev %s\n",
1924 &daddr, &saddr, dev->name);
1925 if (dev->hard_header_len && skb_mac_header_was_set(skb)) {
1926 int i;
1927 const unsigned char *p = skb_mac_header(skb);
1928 printk(KERN_WARNING "ll header: ");
1929 for (i = 0; i < dev->hard_header_len; i++, p++) {
1930 printk("%02x", *p);
1931 if (i < (dev->hard_header_len - 1))
1932 printk(":");
1933 }
1934 printk("\n");
1935 }
1936 }
1937 #endif
1938 }
1939
1940 /* called in rcu_read_lock() section */
1941 static int __mkroute_input(struct sk_buff *skb,
1942 const struct fib_result *res,
1943 struct in_device *in_dev,
1944 __be32 daddr, __be32 saddr, u32 tos,
1945 struct rtable **result)
1946 {
1947 struct rtable *rth;
1948 int err;
1949 struct in_device *out_dev;
1950 unsigned int flags = 0;
1951 __be32 spec_dst;
1952 u32 itag;
1953
1954 /* get a working reference to the output device */
1955 out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res));
1956 if (out_dev == NULL) {
1957 if (net_ratelimit())
1958 printk(KERN_CRIT "Bug in ip_route_input" \
1959 "_slow(). Please, report\n");
1960 return -EINVAL;
1961 }
1962
1963
1964 err = fib_validate_source(saddr, daddr, tos, FIB_RES_OIF(*res),
1965 in_dev->dev, &spec_dst, &itag, skb->mark);
1966 if (err < 0) {
1967 ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr,
1968 saddr);
1969
1970 goto cleanup;
1971 }
1972
1973 if (err)
1974 flags |= RTCF_DIRECTSRC;
1975
1976 if (out_dev == in_dev && err &&
1977 (IN_DEV_SHARED_MEDIA(out_dev) ||
1978 inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res))))
1979 flags |= RTCF_DOREDIRECT;
1980
1981 if (skb->protocol != htons(ETH_P_IP)) {
1982 /* Not IP (i.e. ARP). Do not create route, if it is
1983 * invalid for proxy arp. DNAT routes are always valid.
1984 *
1985 * Proxy arp feature have been extended to allow, ARP
1986 * replies back to the same interface, to support
1987 * Private VLAN switch technologies. See arp.c.
1988 */
1989 if (out_dev == in_dev &&
1990 IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) {
1991 err = -EINVAL;
1992 goto cleanup;
1993 }
1994 }
1995
1996 rth = rt_dst_alloc(IN_DEV_CONF_GET(in_dev, NOPOLICY),
1997 IN_DEV_CONF_GET(out_dev, NOXFRM));
1998 if (!rth) {
1999 err = -ENOBUFS;
2000 goto cleanup;
2001 }
2002
2003 rth->fl.fl4_dst = daddr;
2004 rth->rt_dst = daddr;
2005 rth->fl.fl4_tos = tos;
2006 rth->fl.mark = skb->mark;
2007 rth->fl.fl4_src = saddr;
2008 rth->rt_src = saddr;
2009 rth->rt_gateway = daddr;
2010 rth->rt_iif =
2011 rth->fl.iif = in_dev->dev->ifindex;
2012 rth->dst.dev = (out_dev)->dev;
2013 dev_hold(rth->dst.dev);
2014 rth->fl.oif = 0;
2015 rth->rt_spec_dst= spec_dst;
2016
2017 rth->dst.input = ip_forward;
2018 rth->dst.output = ip_output;
2019 rth->rt_genid = rt_genid(dev_net(rth->dst.dev));
2020
2021 rt_set_nexthop(rth, res, res->fi, res->type, itag);
2022
2023 rth->rt_flags = flags;
2024
2025 *result = rth;
2026 err = 0;
2027 cleanup:
2028 return err;
2029 }
2030
2031 static int ip_mkroute_input(struct sk_buff *skb,
2032 struct fib_result *res,
2033 const struct flowi *fl,
2034 struct in_device *in_dev,
2035 __be32 daddr, __be32 saddr, u32 tos)
2036 {
2037 struct rtable* rth = NULL;
2038 int err;
2039 unsigned hash;
2040
2041 #ifdef CONFIG_IP_ROUTE_MULTIPATH
2042 if (res->fi && res->fi->fib_nhs > 1 && fl->oif == 0)
2043 fib_select_multipath(fl, res);
2044 #endif
2045
2046 /* create a routing cache entry */
2047 err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, &rth);
2048 if (err)
2049 return err;
2050
2051 /* put it into the cache */
2052 hash = rt_hash(daddr, saddr, fl->iif,
2053 rt_genid(dev_net(rth->dst.dev)));
2054 return rt_intern_hash(hash, rth, NULL, skb, fl->iif);
2055 }
2056
2057 /*
2058 * NOTE. We drop all the packets that has local source
2059 * addresses, because every properly looped back packet
2060 * must have correct destination already attached by output routine.
2061 *
2062 * Such approach solves two big problems:
2063 * 1. Not simplex devices are handled properly.
2064 * 2. IP spoofing attempts are filtered with 100% of guarantee.
2065 * called with rcu_read_lock()
2066 */
2067
2068 static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
2069 u8 tos, struct net_device *dev)
2070 {
2071 struct fib_result res;
2072 struct in_device *in_dev = __in_dev_get_rcu(dev);
2073 struct flowi fl = { .fl4_dst = daddr,
2074 .fl4_src = saddr,
2075 .fl4_tos = tos,
2076 .fl4_scope = RT_SCOPE_UNIVERSE,
2077 .mark = skb->mark,
2078 .iif = dev->ifindex };
2079 unsigned flags = 0;
2080 u32 itag = 0;
2081 struct rtable * rth;
2082 unsigned hash;
2083 __be32 spec_dst;
2084 int err = -EINVAL;
2085 struct net * net = dev_net(dev);
2086
2087 /* IP on this device is disabled. */
2088
2089 if (!in_dev)
2090 goto out;
2091
2092 /* Check for the most weird martians, which can be not detected
2093 by fib_lookup.
2094 */
2095
2096 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) ||
2097 ipv4_is_loopback(saddr))
2098 goto martian_source;
2099
2100 if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0))
2101 goto brd_input;
2102
2103 /* Accept zero addresses only to limited broadcast;
2104 * I even do not know to fix it or not. Waiting for complains :-)
2105 */
2106 if (ipv4_is_zeronet(saddr))
2107 goto martian_source;
2108
2109 if (ipv4_is_zeronet(daddr) || ipv4_is_loopback(daddr))
2110 goto martian_destination;
2111
2112 /*
2113 * Now we are ready to route packet.
2114 */
2115 err = fib_lookup(net, &fl, &res);
2116 if (err != 0) {
2117 if (!IN_DEV_FORWARD(in_dev))
2118 goto e_hostunreach;
2119 goto no_route;
2120 }
2121
2122 RT_CACHE_STAT_INC(in_slow_tot);
2123
2124 if (res.type == RTN_BROADCAST)
2125 goto brd_input;
2126
2127 if (res.type == RTN_LOCAL) {
2128 err = fib_validate_source(saddr, daddr, tos,
2129 net->loopback_dev->ifindex,
2130 dev, &spec_dst, &itag, skb->mark);
2131 if (err < 0)
2132 goto martian_source_keep_err;
2133 if (err)
2134 flags |= RTCF_DIRECTSRC;
2135 spec_dst = daddr;
2136 goto local_input;
2137 }
2138
2139 if (!IN_DEV_FORWARD(in_dev))
2140 goto e_hostunreach;
2141 if (res.type != RTN_UNICAST)
2142 goto martian_destination;
2143
2144 err = ip_mkroute_input(skb, &res, &fl, in_dev, daddr, saddr, tos);
2145 out: return err;
2146
2147 brd_input:
2148 if (skb->protocol != htons(ETH_P_IP))
2149 goto e_inval;
2150
2151 if (ipv4_is_zeronet(saddr))
2152 spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK);
2153 else {
2154 err = fib_validate_source(saddr, 0, tos, 0, dev, &spec_dst,
2155 &itag, skb->mark);
2156 if (err < 0)
2157 goto martian_source_keep_err;
2158 if (err)
2159 flags |= RTCF_DIRECTSRC;
2160 }
2161 flags |= RTCF_BROADCAST;
2162 res.type = RTN_BROADCAST;
2163 RT_CACHE_STAT_INC(in_brd);
2164
2165 local_input:
2166 rth = rt_dst_alloc(IN_DEV_CONF_GET(in_dev, NOPOLICY), false);
2167 if (!rth)
2168 goto e_nobufs;
2169
2170 rth->dst.output= ip_rt_bug;
2171 rth->rt_genid = rt_genid(net);
2172
2173 rth->fl.fl4_dst = daddr;
2174 rth->rt_dst = daddr;
2175 rth->fl.fl4_tos = tos;
2176 rth->fl.mark = skb->mark;
2177 rth->fl.fl4_src = saddr;
2178 rth->rt_src = saddr;
2179 #ifdef CONFIG_IP_ROUTE_CLASSID
2180 rth->dst.tclassid = itag;
2181 #endif
2182 rth->rt_iif =
2183 rth->fl.iif = dev->ifindex;
2184 rth->dst.dev = net->loopback_dev;
2185 dev_hold(rth->dst.dev);
2186 rth->rt_gateway = daddr;
2187 rth->rt_spec_dst= spec_dst;
2188 rth->dst.input= ip_local_deliver;
2189 rth->rt_flags = flags|RTCF_LOCAL;
2190 if (res.type == RTN_UNREACHABLE) {
2191 rth->dst.input= ip_error;
2192 rth->dst.error= -err;
2193 rth->rt_flags &= ~RTCF_LOCAL;
2194 }
2195 rth->rt_type = res.type;
2196 hash = rt_hash(daddr, saddr, fl.iif, rt_genid(net));
2197 err = rt_intern_hash(hash, rth, NULL, skb, fl.iif);
2198 goto out;
2199
2200 no_route:
2201 RT_CACHE_STAT_INC(in_no_route);
2202 spec_dst = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE);
2203 res.type = RTN_UNREACHABLE;
2204 if (err == -ESRCH)
2205 err = -ENETUNREACH;
2206 goto local_input;
2207
2208 /*
2209 * Do not cache martian addresses: they should be logged (RFC1812)
2210 */
2211 martian_destination:
2212 RT_CACHE_STAT_INC(in_martian_dst);
2213 #ifdef CONFIG_IP_ROUTE_VERBOSE
2214 if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit())
2215 printk(KERN_WARNING "martian destination %pI4 from %pI4, dev %s\n",
2216 &daddr, &saddr, dev->name);
2217 #endif
2218
2219 e_hostunreach:
2220 err = -EHOSTUNREACH;
2221 goto out;
2222
2223 e_inval:
2224 err = -EINVAL;
2225 goto out;
2226
2227 e_nobufs:
2228 err = -ENOBUFS;
2229 goto out;
2230
2231 martian_source:
2232 err = -EINVAL;
2233 martian_source_keep_err:
2234 ip_handle_martian_source(dev, in_dev, skb, daddr, saddr);
2235 goto out;
2236 }
2237
2238 int ip_route_input_common(struct sk_buff *skb, __be32 daddr, __be32 saddr,
2239 u8 tos, struct net_device *dev, bool noref)
2240 {
2241 struct rtable * rth;
2242 unsigned hash;
2243 int iif = dev->ifindex;
2244 struct net *net;
2245 int res;
2246
2247 net = dev_net(dev);
2248
2249 rcu_read_lock();
2250
2251 if (!rt_caching(net))
2252 goto skip_cache;
2253
2254 tos &= IPTOS_RT_MASK;
2255 hash = rt_hash(daddr, saddr, iif, rt_genid(net));
2256
2257 for (rth = rcu_dereference(rt_hash_table[hash].chain); rth;
2258 rth = rcu_dereference(rth->dst.rt_next)) {
2259 if ((((__force u32)rth->fl.fl4_dst ^ (__force u32)daddr) |
2260 ((__force u32)rth->fl.fl4_src ^ (__force u32)saddr) |
2261 (rth->fl.iif ^ iif) |
2262 rth->fl.oif |
2263 (rth->fl.fl4_tos ^ tos)) == 0 &&
2264 rth->fl.mark == skb->mark &&
2265 net_eq(dev_net(rth->dst.dev), net) &&
2266 !rt_is_expired(rth)) {
2267 if (noref) {
2268 dst_use_noref(&rth->dst, jiffies);
2269 skb_dst_set_noref(skb, &rth->dst);
2270 } else {
2271 dst_use(&rth->dst, jiffies);
2272 skb_dst_set(skb, &rth->dst);
2273 }
2274 RT_CACHE_STAT_INC(in_hit);
2275 rcu_read_unlock();
2276 return 0;
2277 }
2278 RT_CACHE_STAT_INC(in_hlist_search);
2279 }
2280
2281 skip_cache:
2282 /* Multicast recognition logic is moved from route cache to here.
2283 The problem was that too many Ethernet cards have broken/missing
2284 hardware multicast filters :-( As result the host on multicasting
2285 network acquires a lot of useless route cache entries, sort of
2286 SDR messages from all the world. Now we try to get rid of them.
2287 Really, provided software IP multicast filter is organized
2288 reasonably (at least, hashed), it does not result in a slowdown
2289 comparing with route cache reject entries.
2290 Note, that multicast routers are not affected, because
2291 route cache entry is created eventually.
2292 */
2293 if (ipv4_is_multicast(daddr)) {
2294 struct in_device *in_dev = __in_dev_get_rcu(dev);
2295
2296 if (in_dev) {
2297 int our = ip_check_mc(in_dev, daddr, saddr,
2298 ip_hdr(skb)->protocol);
2299 if (our
2300 #ifdef CONFIG_IP_MROUTE
2301 ||
2302 (!ipv4_is_local_multicast(daddr) &&
2303 IN_DEV_MFORWARD(in_dev))
2304 #endif
2305 ) {
2306 int res = ip_route_input_mc(skb, daddr, saddr,
2307 tos, dev, our);
2308 rcu_read_unlock();
2309 return res;
2310 }
2311 }
2312 rcu_read_unlock();
2313 return -EINVAL;
2314 }
2315 res = ip_route_input_slow(skb, daddr, saddr, tos, dev);
2316 rcu_read_unlock();
2317 return res;
2318 }
2319 EXPORT_SYMBOL(ip_route_input_common);
2320
2321 /* called with rcu_read_lock() */
2322 static struct rtable *__mkroute_output(const struct fib_result *res,
2323 const struct flowi *fl,
2324 const struct flowi *oldflp,
2325 struct net_device *dev_out,
2326 unsigned int flags)
2327 {
2328 struct fib_info *fi = res->fi;
2329 u32 tos = RT_FL_TOS(oldflp);
2330 struct in_device *in_dev;
2331 u16 type = res->type;
2332 struct rtable *rth;
2333
2334 if (ipv4_is_loopback(fl->fl4_src) && !(dev_out->flags & IFF_LOOPBACK))
2335 return ERR_PTR(-EINVAL);
2336
2337 if (ipv4_is_lbcast(fl->fl4_dst))
2338 type = RTN_BROADCAST;
2339 else if (ipv4_is_multicast(fl->fl4_dst))
2340 type = RTN_MULTICAST;
2341 else if (ipv4_is_zeronet(fl->fl4_dst))
2342 return ERR_PTR(-EINVAL);
2343
2344 if (dev_out->flags & IFF_LOOPBACK)
2345 flags |= RTCF_LOCAL;
2346
2347 in_dev = __in_dev_get_rcu(dev_out);
2348 if (!in_dev)
2349 return ERR_PTR(-EINVAL);
2350
2351 if (type == RTN_BROADCAST) {
2352 flags |= RTCF_BROADCAST | RTCF_LOCAL;
2353 fi = NULL;
2354 } else if (type == RTN_MULTICAST) {
2355 flags |= RTCF_MULTICAST | RTCF_LOCAL;
2356 if (!ip_check_mc(in_dev, oldflp->fl4_dst, oldflp->fl4_src,
2357 oldflp->proto))
2358 flags &= ~RTCF_LOCAL;
2359 /* If multicast route do not exist use
2360 * default one, but do not gateway in this case.
2361 * Yes, it is hack.
2362 */
2363 if (fi && res->prefixlen < 4)
2364 fi = NULL;
2365 }
2366
2367 rth = rt_dst_alloc(IN_DEV_CONF_GET(in_dev, NOPOLICY),
2368 IN_DEV_CONF_GET(in_dev, NOXFRM));
2369 if (!rth)
2370 return ERR_PTR(-ENOBUFS);
2371
2372 rth->fl.fl4_dst = oldflp->fl4_dst;
2373 rth->fl.fl4_tos = tos;
2374 rth->fl.fl4_src = oldflp->fl4_src;
2375 rth->fl.oif = oldflp->oif;
2376 rth->fl.mark = oldflp->mark;
2377 rth->rt_dst = fl->fl4_dst;
2378 rth->rt_src = fl->fl4_src;
2379 rth->rt_iif = oldflp->oif ? : dev_out->ifindex;
2380 /* get references to the devices that are to be hold by the routing
2381 cache entry */
2382 rth->dst.dev = dev_out;
2383 dev_hold(dev_out);
2384 rth->rt_gateway = fl->fl4_dst;
2385 rth->rt_spec_dst= fl->fl4_src;
2386
2387 rth->dst.output=ip_output;
2388 rth->rt_genid = rt_genid(dev_net(dev_out));
2389
2390 RT_CACHE_STAT_INC(out_slow_tot);
2391
2392 if (flags & RTCF_LOCAL) {
2393 rth->dst.input = ip_local_deliver;
2394 rth->rt_spec_dst = fl->fl4_dst;
2395 }
2396 if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) {
2397 rth->rt_spec_dst = fl->fl4_src;
2398 if (flags & RTCF_LOCAL &&
2399 !(dev_out->flags & IFF_LOOPBACK)) {
2400 rth->dst.output = ip_mc_output;
2401 RT_CACHE_STAT_INC(out_slow_mc);
2402 }
2403 #ifdef CONFIG_IP_MROUTE
2404 if (type == RTN_MULTICAST) {
2405 if (IN_DEV_MFORWARD(in_dev) &&
2406 !ipv4_is_local_multicast(oldflp->fl4_dst)) {
2407 rth->dst.input = ip_mr_input;
2408 rth->dst.output = ip_mc_output;
2409 }
2410 }
2411 #endif
2412 }
2413
2414 rt_set_nexthop(rth, res, fi, type, 0);
2415
2416 rth->rt_flags = flags;
2417 return rth;
2418 }
2419
2420 /*
2421 * Major route resolver routine.
2422 * called with rcu_read_lock();
2423 */
2424
2425 static int ip_route_output_slow(struct net *net, struct rtable **rp,
2426 const struct flowi *oldflp)
2427 {
2428 u32 tos = RT_FL_TOS(oldflp);
2429 struct flowi fl = { .fl4_dst = oldflp->fl4_dst,
2430 .fl4_src = oldflp->fl4_src,
2431 .fl4_tos = tos & IPTOS_RT_MASK,
2432 .fl4_scope = ((tos & RTO_ONLINK) ?
2433 RT_SCOPE_LINK : RT_SCOPE_UNIVERSE),
2434 .mark = oldflp->mark,
2435 .iif = net->loopback_dev->ifindex,
2436 .oif = oldflp->oif };
2437 struct fib_result res;
2438 unsigned int flags = 0;
2439 struct net_device *dev_out = NULL;
2440 struct rtable *rth;
2441 int err;
2442
2443
2444 res.fi = NULL;
2445 #ifdef CONFIG_IP_MULTIPLE_TABLES
2446 res.r = NULL;
2447 #endif
2448
2449 rcu_read_lock();
2450 if (oldflp->fl4_src) {
2451 err = -EINVAL;
2452 if (ipv4_is_multicast(oldflp->fl4_src) ||
2453 ipv4_is_lbcast(oldflp->fl4_src) ||
2454 ipv4_is_zeronet(oldflp->fl4_src))
2455 goto out;
2456
2457 /* I removed check for oif == dev_out->oif here.
2458 It was wrong for two reasons:
2459 1. ip_dev_find(net, saddr) can return wrong iface, if saddr
2460 is assigned to multiple interfaces.
2461 2. Moreover, we are allowed to send packets with saddr
2462 of another iface. --ANK
2463 */
2464
2465 if (oldflp->oif == 0 &&
2466 (ipv4_is_multicast(oldflp->fl4_dst) ||
2467 ipv4_is_lbcast(oldflp->fl4_dst))) {
2468 /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
2469 dev_out = __ip_dev_find(net, oldflp->fl4_src, false);
2470 if (dev_out == NULL)
2471 goto out;
2472
2473 /* Special hack: user can direct multicasts
2474 and limited broadcast via necessary interface
2475 without fiddling with IP_MULTICAST_IF or IP_PKTINFO.
2476 This hack is not just for fun, it allows
2477 vic,vat and friends to work.
2478 They bind socket to loopback, set ttl to zero
2479 and expect that it will work.
2480 From the viewpoint of routing cache they are broken,
2481 because we are not allowed to build multicast path
2482 with loopback source addr (look, routing cache
2483 cannot know, that ttl is zero, so that packet
2484 will not leave this host and route is valid).
2485 Luckily, this hack is good workaround.
2486 */
2487
2488 fl.oif = dev_out->ifindex;
2489 goto make_route;
2490 }
2491
2492 if (!(oldflp->flags & FLOWI_FLAG_ANYSRC)) {
2493 /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
2494 if (!__ip_dev_find(net, oldflp->fl4_src, false))
2495 goto out;
2496 }
2497 }
2498
2499
2500 if (oldflp->oif) {
2501 dev_out = dev_get_by_index_rcu(net, oldflp->oif);
2502 err = -ENODEV;
2503 if (dev_out == NULL)
2504 goto out;
2505
2506 /* RACE: Check return value of inet_select_addr instead. */
2507 if (!(dev_out->flags & IFF_UP) || !__in_dev_get_rcu(dev_out)) {
2508 err = -ENETUNREACH;
2509 goto out;
2510 }
2511 if (ipv4_is_local_multicast(oldflp->fl4_dst) ||
2512 ipv4_is_lbcast(oldflp->fl4_dst)) {
2513 if (!fl.fl4_src)
2514 fl.fl4_src = inet_select_addr(dev_out, 0,
2515 RT_SCOPE_LINK);
2516 goto make_route;
2517 }
2518 if (!fl.fl4_src) {
2519 if (ipv4_is_multicast(oldflp->fl4_dst))
2520 fl.fl4_src = inet_select_addr(dev_out, 0,
2521 fl.fl4_scope);
2522 else if (!oldflp->fl4_dst)
2523 fl.fl4_src = inet_select_addr(dev_out, 0,
2524 RT_SCOPE_HOST);
2525 }
2526 }
2527
2528 if (!fl.fl4_dst) {
2529 fl.fl4_dst = fl.fl4_src;
2530 if (!fl.fl4_dst)
2531 fl.fl4_dst = fl.fl4_src = htonl(INADDR_LOOPBACK);
2532 dev_out = net->loopback_dev;
2533 fl.oif = net->loopback_dev->ifindex;
2534 res.type = RTN_LOCAL;
2535 flags |= RTCF_LOCAL;
2536 goto make_route;
2537 }
2538
2539 if (fib_lookup(net, &fl, &res)) {
2540 res.fi = NULL;
2541 if (oldflp->oif) {
2542 /* Apparently, routing tables are wrong. Assume,
2543 that the destination is on link.
2544
2545 WHY? DW.
2546 Because we are allowed to send to iface
2547 even if it has NO routes and NO assigned
2548 addresses. When oif is specified, routing
2549 tables are looked up with only one purpose:
2550 to catch if destination is gatewayed, rather than
2551 direct. Moreover, if MSG_DONTROUTE is set,
2552 we send packet, ignoring both routing tables
2553 and ifaddr state. --ANK
2554
2555
2556 We could make it even if oif is unknown,
2557 likely IPv6, but we do not.
2558 */
2559
2560 if (fl.fl4_src == 0)
2561 fl.fl4_src = inet_select_addr(dev_out, 0,
2562 RT_SCOPE_LINK);
2563 res.type = RTN_UNICAST;
2564 goto make_route;
2565 }
2566 err = -ENETUNREACH;
2567 goto out;
2568 }
2569
2570 if (res.type == RTN_LOCAL) {
2571 if (!fl.fl4_src) {
2572 if (res.fi->fib_prefsrc)
2573 fl.fl4_src = res.fi->fib_prefsrc;
2574 else
2575 fl.fl4_src = fl.fl4_dst;
2576 }
2577 dev_out = net->loopback_dev;
2578 fl.oif = dev_out->ifindex;
2579 res.fi = NULL;
2580 flags |= RTCF_LOCAL;
2581 goto make_route;
2582 }
2583
2584 #ifdef CONFIG_IP_ROUTE_MULTIPATH
2585 if (res.fi->fib_nhs > 1 && fl.oif == 0)
2586 fib_select_multipath(&fl, &res);
2587 else
2588 #endif
2589 if (!res.prefixlen && res.type == RTN_UNICAST && !fl.oif)
2590 fib_select_default(&res);
2591
2592 if (!fl.fl4_src)
2593 fl.fl4_src = FIB_RES_PREFSRC(res);
2594
2595 dev_out = FIB_RES_DEV(res);
2596 fl.oif = dev_out->ifindex;
2597
2598
2599 make_route:
2600 rth = __mkroute_output(&res, &fl, oldflp, dev_out, flags);
2601 if (IS_ERR(rth))
2602 err = PTR_ERR(rth);
2603 else {
2604 unsigned int hash;
2605
2606 hash = rt_hash(oldflp->fl4_dst, oldflp->fl4_src, oldflp->oif,
2607 rt_genid(dev_net(dev_out)));
2608 err = rt_intern_hash(hash, rth, rp, NULL, oldflp->oif);
2609 }
2610
2611 out:
2612 rcu_read_unlock();
2613 return err;
2614 }
2615
2616 int __ip_route_output_key(struct net *net, struct rtable **rp,
2617 const struct flowi *flp)
2618 {
2619 struct rtable *rth;
2620 unsigned int hash;
2621
2622 if (!rt_caching(net))
2623 goto slow_output;
2624
2625 hash = rt_hash(flp->fl4_dst, flp->fl4_src, flp->oif, rt_genid(net));
2626
2627 rcu_read_lock_bh();
2628 for (rth = rcu_dereference_bh(rt_hash_table[hash].chain); rth;
2629 rth = rcu_dereference_bh(rth->dst.rt_next)) {
2630 if (rth->fl.fl4_dst == flp->fl4_dst &&
2631 rth->fl.fl4_src == flp->fl4_src &&
2632 rt_is_output_route(rth) &&
2633 rth->fl.oif == flp->oif &&
2634 rth->fl.mark == flp->mark &&
2635 !((rth->fl.fl4_tos ^ flp->fl4_tos) &
2636 (IPTOS_RT_MASK | RTO_ONLINK)) &&
2637 net_eq(dev_net(rth->dst.dev), net) &&
2638 !rt_is_expired(rth)) {
2639 dst_use(&rth->dst, jiffies);
2640 RT_CACHE_STAT_INC(out_hit);
2641 rcu_read_unlock_bh();
2642 *rp = rth;
2643 return 0;
2644 }
2645 RT_CACHE_STAT_INC(out_hlist_search);
2646 }
2647 rcu_read_unlock_bh();
2648
2649 slow_output:
2650 return ip_route_output_slow(net, rp, flp);
2651 }
2652 EXPORT_SYMBOL_GPL(__ip_route_output_key);
2653
2654 static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie)
2655 {
2656 return NULL;
2657 }
2658
2659 static unsigned int ipv4_blackhole_default_mtu(const struct dst_entry *dst)
2660 {
2661 return 0;
2662 }
2663
2664 static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
2665 {
2666 }
2667
2668 static struct dst_ops ipv4_dst_blackhole_ops = {
2669 .family = AF_INET,
2670 .protocol = cpu_to_be16(ETH_P_IP),
2671 .destroy = ipv4_dst_destroy,
2672 .check = ipv4_blackhole_dst_check,
2673 .default_mtu = ipv4_blackhole_default_mtu,
2674 .default_advmss = ipv4_default_advmss,
2675 .update_pmtu = ipv4_rt_blackhole_update_pmtu,
2676 };
2677
2678 struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig)
2679 {
2680 struct rtable *rt = dst_alloc(&ipv4_dst_blackhole_ops, 1);
2681 struct rtable *ort = (struct rtable *) dst_orig;
2682
2683 if (rt) {
2684 struct dst_entry *new = &rt->dst;
2685
2686 new->__use = 1;
2687 new->input = dst_discard;
2688 new->output = dst_discard;
2689 dst_copy_metrics(new, &ort->dst);
2690
2691 new->dev = ort->dst.dev;
2692 if (new->dev)
2693 dev_hold(new->dev);
2694
2695 rt->fl = ort->fl;
2696
2697 rt->rt_genid = rt_genid(net);
2698 rt->rt_flags = ort->rt_flags;
2699 rt->rt_type = ort->rt_type;
2700 rt->rt_dst = ort->rt_dst;
2701 rt->rt_src = ort->rt_src;
2702 rt->rt_iif = ort->rt_iif;
2703 rt->rt_gateway = ort->rt_gateway;
2704 rt->rt_spec_dst = ort->rt_spec_dst;
2705 rt->peer = ort->peer;
2706 if (rt->peer)
2707 atomic_inc(&rt->peer->refcnt);
2708 rt->fi = ort->fi;
2709 if (rt->fi)
2710 atomic_inc(&rt->fi->fib_clntref);
2711
2712 dst_free(new);
2713 }
2714
2715 dst_release(dst_orig);
2716
2717 return rt ? &rt->dst : ERR_PTR(-ENOMEM);
2718 }
2719
2720 int ip_route_output_flow(struct net *net, struct rtable **rp, struct flowi *flp,
2721 struct sock *sk)
2722 {
2723 int err;
2724
2725 if ((err = __ip_route_output_key(net, rp, flp)) != 0)
2726 return err;
2727
2728 if (flp->proto) {
2729 if (!flp->fl4_src)
2730 flp->fl4_src = (*rp)->rt_src;
2731 if (!flp->fl4_dst)
2732 flp->fl4_dst = (*rp)->rt_dst;
2733 *rp = (struct rtable *) xfrm_lookup(net, &(*rp)->dst, flp, sk, 0);
2734 if (IS_ERR(*rp)) {
2735 err = PTR_ERR(*rp);
2736 *rp = NULL;
2737 return err;
2738 }
2739 }
2740
2741 return 0;
2742 }
2743 EXPORT_SYMBOL_GPL(ip_route_output_flow);
2744
2745 int ip_route_output_key(struct net *net, struct rtable **rp, struct flowi *flp)
2746 {
2747 return ip_route_output_flow(net, rp, flp, NULL);
2748 }
2749 EXPORT_SYMBOL(ip_route_output_key);
2750
2751 static int rt_fill_info(struct net *net,
2752 struct sk_buff *skb, u32 pid, u32 seq, int event,
2753 int nowait, unsigned int flags)
2754 {
2755 struct rtable *rt = skb_rtable(skb);
2756 struct rtmsg *r;
2757 struct nlmsghdr *nlh;
2758 long expires;
2759 u32 id = 0, ts = 0, tsage = 0, error;
2760
2761 nlh = nlmsg_put(skb, pid, seq, event, sizeof(*r), flags);
2762 if (nlh == NULL)
2763 return -EMSGSIZE;
2764
2765 r = nlmsg_data(nlh);
2766 r->rtm_family = AF_INET;
2767 r->rtm_dst_len = 32;
2768 r->rtm_src_len = 0;
2769 r->rtm_tos = rt->fl.fl4_tos;
2770 r->rtm_table = RT_TABLE_MAIN;
2771 NLA_PUT_U32(skb, RTA_TABLE, RT_TABLE_MAIN);
2772 r->rtm_type = rt->rt_type;
2773 r->rtm_scope = RT_SCOPE_UNIVERSE;
2774 r->rtm_protocol = RTPROT_UNSPEC;
2775 r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
2776 if (rt->rt_flags & RTCF_NOTIFY)
2777 r->rtm_flags |= RTM_F_NOTIFY;
2778
2779 NLA_PUT_BE32(skb, RTA_DST, rt->rt_dst);
2780
2781 if (rt->fl.fl4_src) {
2782 r->rtm_src_len = 32;
2783 NLA_PUT_BE32(skb, RTA_SRC, rt->fl.fl4_src);
2784 }
2785 if (rt->dst.dev)
2786 NLA_PUT_U32(skb, RTA_OIF, rt->dst.dev->ifindex);
2787 #ifdef CONFIG_IP_ROUTE_CLASSID
2788 if (rt->dst.tclassid)
2789 NLA_PUT_U32(skb, RTA_FLOW, rt->dst.tclassid);
2790 #endif
2791 if (rt_is_input_route(rt))
2792 NLA_PUT_BE32(skb, RTA_PREFSRC, rt->rt_spec_dst);
2793 else if (rt->rt_src != rt->fl.fl4_src)
2794 NLA_PUT_BE32(skb, RTA_PREFSRC, rt->rt_src);
2795
2796 if (rt->rt_dst != rt->rt_gateway)
2797 NLA_PUT_BE32(skb, RTA_GATEWAY, rt->rt_gateway);
2798
2799 if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
2800 goto nla_put_failure;
2801
2802 if (rt->fl.mark)
2803 NLA_PUT_BE32(skb, RTA_MARK, rt->fl.mark);
2804
2805 error = rt->dst.error;
2806 expires = (rt->peer && rt->peer->pmtu_expires) ?
2807 rt->peer->pmtu_expires - jiffies : 0;
2808 if (rt->peer) {
2809 inet_peer_refcheck(rt->peer);
2810 id = atomic_read(&rt->peer->ip_id_count) & 0xffff;
2811 if (rt->peer->tcp_ts_stamp) {
2812 ts = rt->peer->tcp_ts;
2813 tsage = get_seconds() - rt->peer->tcp_ts_stamp;
2814 }
2815 }
2816
2817 if (rt_is_input_route(rt)) {
2818 #ifdef CONFIG_IP_MROUTE
2819 __be32 dst = rt->rt_dst;
2820
2821 if (ipv4_is_multicast(dst) && !ipv4_is_local_multicast(dst) &&
2822 IPV4_DEVCONF_ALL(net, MC_FORWARDING)) {
2823 int err = ipmr_get_route(net, skb, r, nowait);
2824 if (err <= 0) {
2825 if (!nowait) {
2826 if (err == 0)
2827 return 0;
2828 goto nla_put_failure;
2829 } else {
2830 if (err == -EMSGSIZE)
2831 goto nla_put_failure;
2832 error = err;
2833 }
2834 }
2835 } else
2836 #endif
2837 NLA_PUT_U32(skb, RTA_IIF, rt->fl.iif);
2838 }
2839
2840 if (rtnl_put_cacheinfo(skb, &rt->dst, id, ts, tsage,
2841 expires, error) < 0)
2842 goto nla_put_failure;
2843
2844 return nlmsg_end(skb, nlh);
2845
2846 nla_put_failure:
2847 nlmsg_cancel(skb, nlh);
2848 return -EMSGSIZE;
2849 }
2850
2851 static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
2852 {
2853 struct net *net = sock_net(in_skb->sk);
2854 struct rtmsg *rtm;
2855 struct nlattr *tb[RTA_MAX+1];
2856 struct rtable *rt = NULL;
2857 __be32 dst = 0;
2858 __be32 src = 0;
2859 u32 iif;
2860 int err;
2861 int mark;
2862 struct sk_buff *skb;
2863
2864 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy);
2865 if (err < 0)
2866 goto errout;
2867
2868 rtm = nlmsg_data(nlh);
2869
2870 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2871 if (skb == NULL) {
2872 err = -ENOBUFS;
2873 goto errout;
2874 }
2875
2876 /* Reserve room for dummy headers, this skb can pass
2877 through good chunk of routing engine.
2878 */
2879 skb_reset_mac_header(skb);
2880 skb_reset_network_header(skb);
2881
2882 /* Bugfix: need to give ip_route_input enough of an IP header to not gag. */
2883 ip_hdr(skb)->protocol = IPPROTO_ICMP;
2884 skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr));
2885
2886 src = tb[RTA_SRC] ? nla_get_be32(tb[RTA_SRC]) : 0;
2887 dst = tb[RTA_DST] ? nla_get_be32(tb[RTA_DST]) : 0;
2888 iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0;
2889 mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0;
2890
2891 if (iif) {
2892 struct net_device *dev;
2893
2894 dev = __dev_get_by_index(net, iif);
2895 if (dev == NULL) {
2896 err = -ENODEV;
2897 goto errout_free;
2898 }
2899
2900 skb->protocol = htons(ETH_P_IP);
2901 skb->dev = dev;
2902 skb->mark = mark;
2903 local_bh_disable();
2904 err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev);
2905 local_bh_enable();
2906
2907 rt = skb_rtable(skb);
2908 if (err == 0 && rt->dst.error)
2909 err = -rt->dst.error;
2910 } else {
2911 struct flowi fl = {
2912 .fl4_dst = dst,
2913 .fl4_src = src,
2914 .fl4_tos = rtm->rtm_tos,
2915 .oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0,
2916 .mark = mark,
2917 };
2918 err = ip_route_output_key(net, &rt, &fl);
2919 }
2920
2921 if (err)
2922 goto errout_free;
2923
2924 skb_dst_set(skb, &rt->dst);
2925 if (rtm->rtm_flags & RTM_F_NOTIFY)
2926 rt->rt_flags |= RTCF_NOTIFY;
2927
2928 err = rt_fill_info(net, skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq,
2929 RTM_NEWROUTE, 0, 0);
2930 if (err <= 0)
2931 goto errout_free;
2932
2933 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
2934 errout:
2935 return err;
2936
2937 errout_free:
2938 kfree_skb(skb);
2939 goto errout;
2940 }
2941
2942 int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb)
2943 {
2944 struct rtable *rt;
2945 int h, s_h;
2946 int idx, s_idx;
2947 struct net *net;
2948
2949 net = sock_net(skb->sk);
2950
2951 s_h = cb->args[0];
2952 if (s_h < 0)
2953 s_h = 0;
2954 s_idx = idx = cb->args[1];
2955 for (h = s_h; h <= rt_hash_mask; h++, s_idx = 0) {
2956 if (!rt_hash_table[h].chain)
2957 continue;
2958 rcu_read_lock_bh();
2959 for (rt = rcu_dereference_bh(rt_hash_table[h].chain), idx = 0; rt;
2960 rt = rcu_dereference_bh(rt->dst.rt_next), idx++) {
2961 if (!net_eq(dev_net(rt->dst.dev), net) || idx < s_idx)
2962 continue;
2963 if (rt_is_expired(rt))
2964 continue;
2965 skb_dst_set_noref(skb, &rt->dst);
2966 if (rt_fill_info(net, skb, NETLINK_CB(cb->skb).pid,
2967 cb->nlh->nlmsg_seq, RTM_NEWROUTE,
2968 1, NLM_F_MULTI) <= 0) {
2969 skb_dst_drop(skb);
2970 rcu_read_unlock_bh();
2971 goto done;
2972 }
2973 skb_dst_drop(skb);
2974 }
2975 rcu_read_unlock_bh();
2976 }
2977
2978 done:
2979 cb->args[0] = h;
2980 cb->args[1] = idx;
2981 return skb->len;
2982 }
2983
2984 void ip_rt_multicast_event(struct in_device *in_dev)
2985 {
2986 rt_cache_flush(dev_net(in_dev->dev), 0);
2987 }
2988
2989 #ifdef CONFIG_SYSCTL
2990 static int ipv4_sysctl_rtcache_flush(ctl_table *__ctl, int write,
2991 void __user *buffer,
2992 size_t *lenp, loff_t *ppos)
2993 {
2994 if (write) {
2995 int flush_delay;
2996 ctl_table ctl;
2997 struct net *net;
2998
2999 memcpy(&ctl, __ctl, sizeof(ctl));
3000 ctl.data = &flush_delay;
3001 proc_dointvec(&ctl, write, buffer, lenp, ppos);
3002
3003 net = (struct net *)__ctl->extra1;
3004 rt_cache_flush(net, flush_delay);
3005 return 0;
3006 }
3007
3008 return -EINVAL;
3009 }
3010
3011 static ctl_table ipv4_route_table[] = {
3012 {
3013 .procname = "gc_thresh",
3014 .data = &ipv4_dst_ops.gc_thresh,
3015 .maxlen = sizeof(int),
3016 .mode = 0644,
3017 .proc_handler = proc_dointvec,
3018 },
3019 {
3020 .procname = "max_size",
3021 .data = &ip_rt_max_size,
3022 .maxlen = sizeof(int),
3023 .mode = 0644,
3024 .proc_handler = proc_dointvec,
3025 },
3026 {
3027 /* Deprecated. Use gc_min_interval_ms */
3028
3029 .procname = "gc_min_interval",
3030 .data = &ip_rt_gc_min_interval,
3031 .maxlen = sizeof(int),
3032 .mode = 0644,
3033 .proc_handler = proc_dointvec_jiffies,
3034 },
3035 {
3036 .procname = "gc_min_interval_ms",
3037 .data = &ip_rt_gc_min_interval,
3038 .maxlen = sizeof(int),
3039 .mode = 0644,
3040 .proc_handler = proc_dointvec_ms_jiffies,
3041 },
3042 {
3043 .procname = "gc_timeout",
3044 .data = &ip_rt_gc_timeout,
3045 .maxlen = sizeof(int),
3046 .mode = 0644,
3047 .proc_handler = proc_dointvec_jiffies,
3048 },
3049 {
3050 .procname = "gc_interval",
3051 .data = &ip_rt_gc_interval,
3052 .maxlen = sizeof(int),
3053 .mode = 0644,
3054 .proc_handler = proc_dointvec_jiffies,
3055 },
3056 {
3057 .procname = "redirect_load",
3058 .data = &ip_rt_redirect_load,
3059 .maxlen = sizeof(int),
3060 .mode = 0644,
3061 .proc_handler = proc_dointvec,
3062 },
3063 {
3064 .procname = "redirect_number",
3065 .data = &ip_rt_redirect_number,
3066 .maxlen = sizeof(int),
3067 .mode = 0644,
3068 .proc_handler = proc_dointvec,
3069 },
3070 {
3071 .procname = "redirect_silence",
3072 .data = &ip_rt_redirect_silence,
3073 .maxlen = sizeof(int),
3074 .mode = 0644,
3075 .proc_handler = proc_dointvec,
3076 },
3077 {
3078 .procname = "error_cost",
3079 .data = &ip_rt_error_cost,
3080 .maxlen = sizeof(int),
3081 .mode = 0644,
3082 .proc_handler = proc_dointvec,
3083 },
3084 {
3085 .procname = "error_burst",
3086 .data = &ip_rt_error_burst,
3087 .maxlen = sizeof(int),
3088 .mode = 0644,
3089 .proc_handler = proc_dointvec,
3090 },
3091 {
3092 .procname = "gc_elasticity",
3093 .data = &ip_rt_gc_elasticity,
3094 .maxlen = sizeof(int),
3095 .mode = 0644,
3096 .proc_handler = proc_dointvec,
3097 },
3098 {
3099 .procname = "mtu_expires",
3100 .data = &ip_rt_mtu_expires,
3101 .maxlen = sizeof(int),
3102 .mode = 0644,
3103 .proc_handler = proc_dointvec_jiffies,
3104 },
3105 {
3106 .procname = "min_pmtu",
3107 .data = &ip_rt_min_pmtu,
3108 .maxlen = sizeof(int),
3109 .mode = 0644,
3110 .proc_handler = proc_dointvec,
3111 },
3112 {
3113 .procname = "min_adv_mss",
3114 .data = &ip_rt_min_advmss,
3115 .maxlen = sizeof(int),
3116 .mode = 0644,
3117 .proc_handler = proc_dointvec,
3118 },
3119 { }
3120 };
3121
3122 static struct ctl_table empty[1];
3123
3124 static struct ctl_table ipv4_skeleton[] =
3125 {
3126 { .procname = "route",
3127 .mode = 0555, .child = ipv4_route_table},
3128 { .procname = "neigh",
3129 .mode = 0555, .child = empty},
3130 { }
3131 };
3132
3133 static __net_initdata struct ctl_path ipv4_path[] = {
3134 { .procname = "net", },
3135 { .procname = "ipv4", },
3136 { },
3137 };
3138
3139 static struct ctl_table ipv4_route_flush_table[] = {
3140 {
3141 .procname = "flush",
3142 .maxlen = sizeof(int),
3143 .mode = 0200,
3144 .proc_handler = ipv4_sysctl_rtcache_flush,
3145 },
3146 { },
3147 };
3148
3149 static __net_initdata struct ctl_path ipv4_route_path[] = {
3150 { .procname = "net", },
3151 { .procname = "ipv4", },
3152 { .procname = "route", },
3153 { },
3154 };
3155
3156 static __net_init int sysctl_route_net_init(struct net *net)
3157 {
3158 struct ctl_table *tbl;
3159
3160 tbl = ipv4_route_flush_table;
3161 if (!net_eq(net, &init_net)) {
3162 tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL);
3163 if (tbl == NULL)
3164 goto err_dup;
3165 }
3166 tbl[0].extra1 = net;
3167
3168 net->ipv4.route_hdr =
3169 register_net_sysctl_table(net, ipv4_route_path, tbl);
3170 if (net->ipv4.route_hdr == NULL)
3171 goto err_reg;
3172 return 0;
3173
3174 err_reg:
3175 if (tbl != ipv4_route_flush_table)
3176 kfree(tbl);
3177 err_dup:
3178 return -ENOMEM;
3179 }
3180
3181 static __net_exit void sysctl_route_net_exit(struct net *net)
3182 {
3183 struct ctl_table *tbl;
3184
3185 tbl = net->ipv4.route_hdr->ctl_table_arg;
3186 unregister_net_sysctl_table(net->ipv4.route_hdr);
3187 BUG_ON(tbl == ipv4_route_flush_table);
3188 kfree(tbl);
3189 }
3190
3191 static __net_initdata struct pernet_operations sysctl_route_ops = {
3192 .init = sysctl_route_net_init,
3193 .exit = sysctl_route_net_exit,
3194 };
3195 #endif
3196
3197 static __net_init int rt_genid_init(struct net *net)
3198 {
3199 get_random_bytes(&net->ipv4.rt_genid,
3200 sizeof(net->ipv4.rt_genid));
3201 return 0;
3202 }
3203
3204 static __net_initdata struct pernet_operations rt_genid_ops = {
3205 .init = rt_genid_init,
3206 };
3207
3208
3209 #ifdef CONFIG_IP_ROUTE_CLASSID
3210 struct ip_rt_acct __percpu *ip_rt_acct __read_mostly;
3211 #endif /* CONFIG_IP_ROUTE_CLASSID */
3212
3213 static __initdata unsigned long rhash_entries;
3214 static int __init set_rhash_entries(char *str)
3215 {
3216 if (!str)
3217 return 0;
3218 rhash_entries = simple_strtoul(str, &str, 0);
3219 return 1;
3220 }
3221 __setup("rhash_entries=", set_rhash_entries);
3222
3223 int __init ip_rt_init(void)
3224 {
3225 int rc = 0;
3226
3227 #ifdef CONFIG_IP_ROUTE_CLASSID
3228 ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct));
3229 if (!ip_rt_acct)
3230 panic("IP: failed to allocate ip_rt_acct\n");
3231 #endif
3232
3233 ipv4_dst_ops.kmem_cachep =
3234 kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0,
3235 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
3236
3237 ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep;
3238
3239 if (dst_entries_init(&ipv4_dst_ops) < 0)
3240 panic("IP: failed to allocate ipv4_dst_ops counter\n");
3241
3242 if (dst_entries_init(&ipv4_dst_blackhole_ops) < 0)
3243 panic("IP: failed to allocate ipv4_dst_blackhole_ops counter\n");
3244
3245 rt_hash_table = (struct rt_hash_bucket *)
3246 alloc_large_system_hash("IP route cache",
3247 sizeof(struct rt_hash_bucket),
3248 rhash_entries,
3249 (totalram_pages >= 128 * 1024) ?
3250 15 : 17,
3251 0,
3252 &rt_hash_log,
3253 &rt_hash_mask,
3254 rhash_entries ? 0 : 512 * 1024);
3255 memset(rt_hash_table, 0, (rt_hash_mask + 1) * sizeof(struct rt_hash_bucket));
3256 rt_hash_lock_init();
3257
3258 ipv4_dst_ops.gc_thresh = (rt_hash_mask + 1);
3259 ip_rt_max_size = (rt_hash_mask + 1) * 16;
3260
3261 devinet_init();
3262 ip_fib_init();
3263
3264 if (ip_rt_proc_init())
3265 printk(KERN_ERR "Unable to create route proc files\n");
3266 #ifdef CONFIG_XFRM
3267 xfrm_init();
3268 xfrm4_init(ip_rt_max_size);
3269 #endif
3270 rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL);
3271
3272 #ifdef CONFIG_SYSCTL
3273 register_pernet_subsys(&sysctl_route_ops);
3274 #endif
3275 register_pernet_subsys(&rt_genid_ops);
3276 return rc;
3277 }
3278
3279 #ifdef CONFIG_SYSCTL
3280 /*
3281 * We really need to sanitize the damn ipv4 init order, then all
3282 * this nonsense will go away.
3283 */
3284 void __init ip_static_sysctl_init(void)
3285 {
3286 register_sysctl_paths(ipv4_path, ipv4_skeleton);
3287 }
3288 #endif
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree