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ipv4: remove flush_mutex from ipv4_sysctl_rtcache_flush
[firewire-audio.git] / net / ipv4 / route.c
blob79c1e74263a19876c9e6cf6f4a34fbd3332c3473
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 <net/dst.h>
94 #include <net/net_namespace.h>
95 #include <net/protocol.h>
96 #include <net/ip.h>
97 #include <net/route.h>
98 #include <net/inetpeer.h>
99 #include <net/sock.h>
100 #include <net/ip_fib.h>
101 #include <net/arp.h>
102 #include <net/tcp.h>
103 #include <net/icmp.h>
104 #include <net/xfrm.h>
105 #include <net/netevent.h>
106 #include <net/rtnetlink.h>
107 #ifdef CONFIG_SYSCTL
108 #include <linux/sysctl.h>
109 #endif
110
111 #define RT_FL_TOS(oldflp) \
112 ((u32)(oldflp->fl4_tos & (IPTOS_RT_MASK | RTO_ONLINK)))
113
114 #define IP_MAX_MTU 0xFFF0
115
116 #define RT_GC_TIMEOUT (300*HZ)
117
118 static int ip_rt_max_size;
119 static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT;
120 static int ip_rt_gc_interval __read_mostly = 60 * HZ;
121 static int ip_rt_gc_min_interval __read_mostly = HZ / 2;
122 static int ip_rt_redirect_number __read_mostly = 9;
123 static int ip_rt_redirect_load __read_mostly = HZ / 50;
124 static int ip_rt_redirect_silence __read_mostly = ((HZ / 50) << (9 + 1));
125 static int ip_rt_error_cost __read_mostly = HZ;
126 static int ip_rt_error_burst __read_mostly = 5 * HZ;
127 static int ip_rt_gc_elasticity __read_mostly = 8;
128 static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ;
129 static int ip_rt_min_pmtu __read_mostly = 512 + 20 + 20;
130 static int ip_rt_min_advmss __read_mostly = 256;
131 static int ip_rt_secret_interval __read_mostly = 10 * 60 * HZ;
132
133 static void rt_worker_func(struct work_struct *work);
134 static DECLARE_DELAYED_WORK(expires_work, rt_worker_func);
135
136 /*
137 * Interface to generic destination cache.
138 */
139
140 static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie);
141 static void ipv4_dst_destroy(struct dst_entry *dst);
142 static void ipv4_dst_ifdown(struct dst_entry *dst,
143 struct net_device *dev, int how);
144 static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst);
145 static void ipv4_link_failure(struct sk_buff *skb);
146 static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
147 static int rt_garbage_collect(struct dst_ops *ops);
148
149
150 static struct dst_ops ipv4_dst_ops = {
151 .family = AF_INET,
152 .protocol = __constant_htons(ETH_P_IP),
153 .gc = rt_garbage_collect,
154 .check = ipv4_dst_check,
155 .destroy = ipv4_dst_destroy,
156 .ifdown = ipv4_dst_ifdown,
157 .negative_advice = ipv4_negative_advice,
158 .link_failure = ipv4_link_failure,
159 .update_pmtu = ip_rt_update_pmtu,
160 .local_out = __ip_local_out,
161 .entry_size = sizeof(struct rtable),
162 .entries = ATOMIC_INIT(0),
163 };
164
165 #define ECN_OR_COST(class) TC_PRIO_##class
166
167 const __u8 ip_tos2prio[16] = {
168 TC_PRIO_BESTEFFORT,
169 ECN_OR_COST(FILLER),
170 TC_PRIO_BESTEFFORT,
171 ECN_OR_COST(BESTEFFORT),
172 TC_PRIO_BULK,
173 ECN_OR_COST(BULK),
174 TC_PRIO_BULK,
175 ECN_OR_COST(BULK),
176 TC_PRIO_INTERACTIVE,
177 ECN_OR_COST(INTERACTIVE),
178 TC_PRIO_INTERACTIVE,
179 ECN_OR_COST(INTERACTIVE),
180 TC_PRIO_INTERACTIVE_BULK,
181 ECN_OR_COST(INTERACTIVE_BULK),
182 TC_PRIO_INTERACTIVE_BULK,
183 ECN_OR_COST(INTERACTIVE_BULK)
184 };
185
186
187 /*
188 * Route cache.
189 */
190
191 /* The locking scheme is rather straight forward:
192 *
193 * 1) Read-Copy Update protects the buckets of the central route hash.
194 * 2) Only writers remove entries, and they hold the lock
195 * as they look at rtable reference counts.
196 * 3) Only readers acquire references to rtable entries,
197 * they do so with atomic increments and with the
198 * lock held.
199 */
200
201 struct rt_hash_bucket {
202 struct rtable *chain;
203 };
204 #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) || \
205 defined(CONFIG_PROVE_LOCKING)
206 /*
207 * Instead of using one spinlock for each rt_hash_bucket, we use a table of spinlocks
208 * The size of this table is a power of two and depends on the number of CPUS.
209 * (on lockdep we have a quite big spinlock_t, so keep the size down there)
210 */
211 #ifdef CONFIG_LOCKDEP
212 # define RT_HASH_LOCK_SZ 256
213 #else
214 # if NR_CPUS >= 32
215 # define RT_HASH_LOCK_SZ 4096
216 # elif NR_CPUS >= 16
217 # define RT_HASH_LOCK_SZ 2048
218 # elif NR_CPUS >= 8
219 # define RT_HASH_LOCK_SZ 1024
220 # elif NR_CPUS >= 4
221 # define RT_HASH_LOCK_SZ 512
222 # else
223 # define RT_HASH_LOCK_SZ 256
224 # endif
225 #endif
226
227 static spinlock_t *rt_hash_locks;
228 # define rt_hash_lock_addr(slot) &rt_hash_locks[(slot) & (RT_HASH_LOCK_SZ - 1)]
229
230 static __init void rt_hash_lock_init(void)
231 {
232 int i;
233
234 rt_hash_locks = kmalloc(sizeof(spinlock_t) * RT_HASH_LOCK_SZ,
235 GFP_KERNEL);
236 if (!rt_hash_locks)
237 panic("IP: failed to allocate rt_hash_locks\n");
238
239 for (i = 0; i < RT_HASH_LOCK_SZ; i++)
240 spin_lock_init(&rt_hash_locks[i]);
241 }
242 #else
243 # define rt_hash_lock_addr(slot) NULL
244
245 static inline void rt_hash_lock_init(void)
246 {
247 }
248 #endif
249
250 static struct rt_hash_bucket *rt_hash_table __read_mostly;
251 static unsigned rt_hash_mask __read_mostly;
252 static unsigned int rt_hash_log __read_mostly;
253
254 static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat);
255 #define RT_CACHE_STAT_INC(field) \
256 (__raw_get_cpu_var(rt_cache_stat).field++)
257
258 static inline unsigned int rt_hash(__be32 daddr, __be32 saddr, int idx,
259 int genid)
260 {
261 return jhash_3words((__force u32)(__be32)(daddr),
262 (__force u32)(__be32)(saddr),
263 idx, genid)
264 & rt_hash_mask;
265 }
266
267 static inline int rt_genid(struct net *net)
268 {
269 return atomic_read(&net->ipv4.rt_genid);
270 }
271
272 #ifdef CONFIG_PROC_FS
273 struct rt_cache_iter_state {
274 struct seq_net_private p;
275 int bucket;
276 int genid;
277 };
278
279 static struct rtable *rt_cache_get_first(struct seq_file *seq)
280 {
281 struct rt_cache_iter_state *st = seq->private;
282 struct rtable *r = NULL;
283
284 for (st->bucket = rt_hash_mask; st->bucket >= 0; --st->bucket) {
285 rcu_read_lock_bh();
286 r = rcu_dereference(rt_hash_table[st->bucket].chain);
287 while (r) {
288 if (dev_net(r->u.dst.dev) == seq_file_net(seq) &&
289 r->rt_genid == st->genid)
290 return r;
291 r = rcu_dereference(r->u.dst.rt_next);
292 }
293 rcu_read_unlock_bh();
294 }
295 return r;
296 }
297
298 static struct rtable *__rt_cache_get_next(struct seq_file *seq,
299 struct rtable *r)
300 {
301 struct rt_cache_iter_state *st = seq->private;
302 r = r->u.dst.rt_next;
303 while (!r) {
304 rcu_read_unlock_bh();
305 if (--st->bucket < 0)
306 break;
307 rcu_read_lock_bh();
308 r = rt_hash_table[st->bucket].chain;
309 }
310 return rcu_dereference(r);
311 }
312
313 static struct rtable *rt_cache_get_next(struct seq_file *seq,
314 struct rtable *r)
315 {
316 struct rt_cache_iter_state *st = seq->private;
317 while ((r = __rt_cache_get_next(seq, r)) != NULL) {
318 if (dev_net(r->u.dst.dev) != seq_file_net(seq))
319 continue;
320 if (r->rt_genid == st->genid)
321 break;
322 }
323 return r;
324 }
325
326 static struct rtable *rt_cache_get_idx(struct seq_file *seq, loff_t pos)
327 {
328 struct rtable *r = rt_cache_get_first(seq);
329
330 if (r)
331 while (pos && (r = rt_cache_get_next(seq, r)))
332 --pos;
333 return pos ? NULL : r;
334 }
335
336 static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
337 {
338 struct rt_cache_iter_state *st = seq->private;
339 if (*pos)
340 return rt_cache_get_idx(seq, *pos - 1);
341 st->genid = rt_genid(seq_file_net(seq));
342 return SEQ_START_TOKEN;
343 }
344
345 static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
346 {
347 struct rtable *r;
348
349 if (v == SEQ_START_TOKEN)
350 r = rt_cache_get_first(seq);
351 else
352 r = rt_cache_get_next(seq, v);
353 ++*pos;
354 return r;
355 }
356
357 static void rt_cache_seq_stop(struct seq_file *seq, void *v)
358 {
359 if (v && v != SEQ_START_TOKEN)
360 rcu_read_unlock_bh();
361 }
362
363 static int rt_cache_seq_show(struct seq_file *seq, void *v)
364 {
365 if (v == SEQ_START_TOKEN)
366 seq_printf(seq, "%-127s\n",
367 "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t"
368 "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t"
369 "HHUptod\tSpecDst");
370 else {
371 struct rtable *r = v;
372 int len;
373
374 seq_printf(seq, "%s\t%08lX\t%08lX\t%8X\t%d\t%u\t%d\t"
375 "%08lX\t%d\t%u\t%u\t%02X\t%d\t%1d\t%08X%n",
376 r->u.dst.dev ? r->u.dst.dev->name : "*",
377 (unsigned long)r->rt_dst, (unsigned long)r->rt_gateway,
378 r->rt_flags, atomic_read(&r->u.dst.__refcnt),
379 r->u.dst.__use, 0, (unsigned long)r->rt_src,
380 (dst_metric(&r->u.dst, RTAX_ADVMSS) ?
381 (int)dst_metric(&r->u.dst, RTAX_ADVMSS) + 40 : 0),
382 dst_metric(&r->u.dst, RTAX_WINDOW),
383 (int)((dst_metric(&r->u.dst, RTAX_RTT) >> 3) +
384 dst_metric(&r->u.dst, RTAX_RTTVAR)),
385 r->fl.fl4_tos,
386 r->u.dst.hh ? atomic_read(&r->u.dst.hh->hh_refcnt) : -1,
387 r->u.dst.hh ? (r->u.dst.hh->hh_output ==
388 dev_queue_xmit) : 0,
389 r->rt_spec_dst, &len);
390
391 seq_printf(seq, "%*s\n", 127 - len, "");
392 }
393 return 0;
394 }
395
396 static const struct seq_operations rt_cache_seq_ops = {
397 .start = rt_cache_seq_start,
398 .next = rt_cache_seq_next,
399 .stop = rt_cache_seq_stop,
400 .show = rt_cache_seq_show,
401 };
402
403 static int rt_cache_seq_open(struct inode *inode, struct file *file)
404 {
405 return seq_open_net(inode, file, &rt_cache_seq_ops,
406 sizeof(struct rt_cache_iter_state));
407 }
408
409 static const struct file_operations rt_cache_seq_fops = {
410 .owner = THIS_MODULE,
411 .open = rt_cache_seq_open,
412 .read = seq_read,
413 .llseek = seq_lseek,
414 .release = seq_release_net,
415 };
416
417
418 static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos)
419 {
420 int cpu;
421
422 if (*pos == 0)
423 return SEQ_START_TOKEN;
424
425 for (cpu = *pos-1; cpu < NR_CPUS; ++cpu) {
426 if (!cpu_possible(cpu))
427 continue;
428 *pos = cpu+1;
429 return &per_cpu(rt_cache_stat, cpu);
430 }
431 return NULL;
432 }
433
434 static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos)
435 {
436 int cpu;
437
438 for (cpu = *pos; cpu < NR_CPUS; ++cpu) {
439 if (!cpu_possible(cpu))
440 continue;
441 *pos = cpu+1;
442 return &per_cpu(rt_cache_stat, cpu);
443 }
444 return NULL;
445
446 }
447
448 static void rt_cpu_seq_stop(struct seq_file *seq, void *v)
449 {
450
451 }
452
453 static int rt_cpu_seq_show(struct seq_file *seq, void *v)
454 {
455 struct rt_cache_stat *st = v;
456
457 if (v == SEQ_START_TOKEN) {
458 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");
459 return 0;
460 }
461
462 seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x "
463 " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n",
464 atomic_read(&ipv4_dst_ops.entries),
465 st->in_hit,
466 st->in_slow_tot,
467 st->in_slow_mc,
468 st->in_no_route,
469 st->in_brd,
470 st->in_martian_dst,
471 st->in_martian_src,
472
473 st->out_hit,
474 st->out_slow_tot,
475 st->out_slow_mc,
476
477 st->gc_total,
478 st->gc_ignored,
479 st->gc_goal_miss,
480 st->gc_dst_overflow,
481 st->in_hlist_search,
482 st->out_hlist_search
483 );
484 return 0;
485 }
486
487 static const struct seq_operations rt_cpu_seq_ops = {
488 .start = rt_cpu_seq_start,
489 .next = rt_cpu_seq_next,
490 .stop = rt_cpu_seq_stop,
491 .show = rt_cpu_seq_show,
492 };
493
494
495 static int rt_cpu_seq_open(struct inode *inode, struct file *file)
496 {
497 return seq_open(file, &rt_cpu_seq_ops);
498 }
499
500 static const struct file_operations rt_cpu_seq_fops = {
501 .owner = THIS_MODULE,
502 .open = rt_cpu_seq_open,
503 .read = seq_read,
504 .llseek = seq_lseek,
505 .release = seq_release,
506 };
507
508 #ifdef CONFIG_NET_CLS_ROUTE
509 static int ip_rt_acct_read(char *buffer, char **start, off_t offset,
510 int length, int *eof, void *data)
511 {
512 unsigned int i;
513
514 if ((offset & 3) || (length & 3))
515 return -EIO;
516
517 if (offset >= sizeof(struct ip_rt_acct) * 256) {
518 *eof = 1;
519 return 0;
520 }
521
522 if (offset + length >= sizeof(struct ip_rt_acct) * 256) {
523 length = sizeof(struct ip_rt_acct) * 256 - offset;
524 *eof = 1;
525 }
526
527 offset /= sizeof(u32);
528
529 if (length > 0) {
530 u32 *dst = (u32 *) buffer;
531
532 *start = buffer;
533 memset(dst, 0, length);
534
535 for_each_possible_cpu(i) {
536 unsigned int j;
537 u32 *src;
538
539 src = ((u32 *) per_cpu_ptr(ip_rt_acct, i)) + offset;
540 for (j = 0; j < length/4; j++)
541 dst[j] += src[j];
542 }
543 }
544 return length;
545 }
546 #endif
547
548 static int __net_init ip_rt_do_proc_init(struct net *net)
549 {
550 struct proc_dir_entry *pde;
551
552 pde = proc_net_fops_create(net, "rt_cache", S_IRUGO,
553 &rt_cache_seq_fops);
554 if (!pde)
555 goto err1;
556
557 pde = proc_create("rt_cache", S_IRUGO,
558 net->proc_net_stat, &rt_cpu_seq_fops);
559 if (!pde)
560 goto err2;
561
562 #ifdef CONFIG_NET_CLS_ROUTE
563 pde = create_proc_read_entry("rt_acct", 0, net->proc_net,
564 ip_rt_acct_read, NULL);
565 if (!pde)
566 goto err3;
567 #endif
568 return 0;
569
570 #ifdef CONFIG_NET_CLS_ROUTE
571 err3:
572 remove_proc_entry("rt_cache", net->proc_net_stat);
573 #endif
574 err2:
575 remove_proc_entry("rt_cache", net->proc_net);
576 err1:
577 return -ENOMEM;
578 }
579
580 static void __net_exit ip_rt_do_proc_exit(struct net *net)
581 {
582 remove_proc_entry("rt_cache", net->proc_net_stat);
583 remove_proc_entry("rt_cache", net->proc_net);
584 remove_proc_entry("rt_acct", net->proc_net);
585 }
586
587 static struct pernet_operations ip_rt_proc_ops __net_initdata = {
588 .init = ip_rt_do_proc_init,
589 .exit = ip_rt_do_proc_exit,
590 };
591
592 static int __init ip_rt_proc_init(void)
593 {
594 return register_pernet_subsys(&ip_rt_proc_ops);
595 }
596
597 #else
598 static inline int ip_rt_proc_init(void)
599 {
600 return 0;
601 }
602 #endif /* CONFIG_PROC_FS */
603
604 static inline void rt_free(struct rtable *rt)
605 {
606 call_rcu_bh(&rt->u.dst.rcu_head, dst_rcu_free);
607 }
608
609 static inline void rt_drop(struct rtable *rt)
610 {
611 ip_rt_put(rt);
612 call_rcu_bh(&rt->u.dst.rcu_head, dst_rcu_free);
613 }
614
615 static inline int rt_fast_clean(struct rtable *rth)
616 {
617 /* Kill broadcast/multicast entries very aggresively, if they
618 collide in hash table with more useful entries */
619 return (rth->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) &&
620 rth->fl.iif && rth->u.dst.rt_next;
621 }
622
623 static inline int rt_valuable(struct rtable *rth)
624 {
625 return (rth->rt_flags & (RTCF_REDIRECTED | RTCF_NOTIFY)) ||
626 rth->u.dst.expires;
627 }
628
629 static int rt_may_expire(struct rtable *rth, unsigned long tmo1, unsigned long tmo2)
630 {
631 unsigned long age;
632 int ret = 0;
633
634 if (atomic_read(&rth->u.dst.__refcnt))
635 goto out;
636
637 ret = 1;
638 if (rth->u.dst.expires &&
639 time_after_eq(jiffies, rth->u.dst.expires))
640 goto out;
641
642 age = jiffies - rth->u.dst.lastuse;
643 ret = 0;
644 if ((age <= tmo1 && !rt_fast_clean(rth)) ||
645 (age <= tmo2 && rt_valuable(rth)))
646 goto out;
647 ret = 1;
648 out: return ret;
649 }
650
651 /* Bits of score are:
652 * 31: very valuable
653 * 30: not quite useless
654 * 29..0: usage counter
655 */
656 static inline u32 rt_score(struct rtable *rt)
657 {
658 u32 score = jiffies - rt->u.dst.lastuse;
659
660 score = ~score & ~(3<<30);
661
662 if (rt_valuable(rt))
663 score |= (1<<31);
664
665 if (!rt->fl.iif ||
666 !(rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST|RTCF_LOCAL)))
667 score |= (1<<30);
668
669 return score;
670 }
671
672 static inline int compare_keys(struct flowi *fl1, struct flowi *fl2)
673 {
674 return ((__force u32)((fl1->nl_u.ip4_u.daddr ^ fl2->nl_u.ip4_u.daddr) |
675 (fl1->nl_u.ip4_u.saddr ^ fl2->nl_u.ip4_u.saddr)) |
676 (fl1->mark ^ fl2->mark) |
677 (*(u16 *)&fl1->nl_u.ip4_u.tos ^
678 *(u16 *)&fl2->nl_u.ip4_u.tos) |
679 (fl1->oif ^ fl2->oif) |
680 (fl1->iif ^ fl2->iif)) == 0;
681 }
682
683 static inline int compare_netns(struct rtable *rt1, struct rtable *rt2)
684 {
685 return dev_net(rt1->u.dst.dev) == dev_net(rt2->u.dst.dev);
686 }
687
688 static inline int rt_is_expired(struct rtable *rth)
689 {
690 return rth->rt_genid != rt_genid(dev_net(rth->u.dst.dev));
691 }
692
693 /*
694 * Perform a full scan of hash table and free all entries.
695 * Can be called by a softirq or a process.
696 * In the later case, we want to be reschedule if necessary
697 */
698 static void rt_do_flush(int process_context)
699 {
700 unsigned int i;
701 struct rtable *rth, *next;
702 struct rtable * tail;
703
704 for (i = 0; i <= rt_hash_mask; i++) {
705 if (process_context && need_resched())
706 cond_resched();
707 rth = rt_hash_table[i].chain;
708 if (!rth)
709 continue;
710
711 spin_lock_bh(rt_hash_lock_addr(i));
712 #ifdef CONFIG_NET_NS
713 {
714 struct rtable ** prev, * p;
715
716 rth = rt_hash_table[i].chain;
717
718 /* defer releasing the head of the list after spin_unlock */
719 for (tail = rth; tail; tail = tail->u.dst.rt_next)
720 if (!rt_is_expired(tail))
721 break;
722 if (rth != tail)
723 rt_hash_table[i].chain = tail;
724
725 /* call rt_free on entries after the tail requiring flush */
726 prev = &rt_hash_table[i].chain;
727 for (p = *prev; p; p = next) {
728 next = p->u.dst.rt_next;
729 if (!rt_is_expired(p)) {
730 prev = &p->u.dst.rt_next;
731 } else {
732 *prev = next;
733 rt_free(p);
734 }
735 }
736 }
737 #else
738 rth = rt_hash_table[i].chain;
739 rt_hash_table[i].chain = NULL;
740 tail = NULL;
741 #endif
742 spin_unlock_bh(rt_hash_lock_addr(i));
743
744 for (; rth != tail; rth = next) {
745 next = rth->u.dst.rt_next;
746 rt_free(rth);
747 }
748 }
749 }
750
751 static void rt_check_expire(void)
752 {
753 static unsigned int rover;
754 unsigned int i = rover, goal;
755 struct rtable *rth, **rthp;
756 u64 mult;
757
758 mult = ((u64)ip_rt_gc_interval) << rt_hash_log;
759 if (ip_rt_gc_timeout > 1)
760 do_div(mult, ip_rt_gc_timeout);
761 goal = (unsigned int)mult;
762 if (goal > rt_hash_mask)
763 goal = rt_hash_mask + 1;
764 for (; goal > 0; goal--) {
765 unsigned long tmo = ip_rt_gc_timeout;
766
767 i = (i + 1) & rt_hash_mask;
768 rthp = &rt_hash_table[i].chain;
769
770 if (need_resched())
771 cond_resched();
772
773 if (*rthp == NULL)
774 continue;
775 spin_lock_bh(rt_hash_lock_addr(i));
776 while ((rth = *rthp) != NULL) {
777 if (rt_is_expired(rth)) {
778 *rthp = rth->u.dst.rt_next;
779 rt_free(rth);
780 continue;
781 }
782 if (rth->u.dst.expires) {
783 /* Entry is expired even if it is in use */
784 if (time_before_eq(jiffies, rth->u.dst.expires)) {
785 tmo >>= 1;
786 rthp = &rth->u.dst.rt_next;
787 continue;
788 }
789 } else if (!rt_may_expire(rth, tmo, ip_rt_gc_timeout)) {
790 tmo >>= 1;
791 rthp = &rth->u.dst.rt_next;
792 continue;
793 }
794
795 /* Cleanup aged off entries. */
796 *rthp = rth->u.dst.rt_next;
797 rt_free(rth);
798 }
799 spin_unlock_bh(rt_hash_lock_addr(i));
800 }
801 rover = i;
802 }
803
804 /*
805 * rt_worker_func() is run in process context.
806 * we call rt_check_expire() to scan part of the hash table
807 */
808 static void rt_worker_func(struct work_struct *work)
809 {
810 rt_check_expire();
811 schedule_delayed_work(&expires_work, ip_rt_gc_interval);
812 }
813
814 /*
815 * Pertubation of rt_genid by a small quantity [1..256]
816 * Using 8 bits of shuffling ensure we can call rt_cache_invalidate()
817 * many times (2^24) without giving recent rt_genid.
818 * Jenkins hash is strong enough that litle changes of rt_genid are OK.
819 */
820 static void rt_cache_invalidate(struct net *net)
821 {
822 unsigned char shuffle;
823
824 get_random_bytes(&shuffle, sizeof(shuffle));
825 atomic_add(shuffle + 1U, &net->ipv4.rt_genid);
826 }
827
828 /*
829 * delay < 0 : invalidate cache (fast : entries will be deleted later)
830 * delay >= 0 : invalidate & flush cache (can be long)
831 */
832 void rt_cache_flush(struct net *net, int delay)
833 {
834 rt_cache_invalidate(net);
835 if (delay >= 0)
836 rt_do_flush(!in_softirq());
837 }
838
839 /*
840 * We change rt_genid and let gc do the cleanup
841 */
842 static void rt_secret_rebuild(unsigned long __net)
843 {
844 struct net *net = (struct net *)__net;
845 rt_cache_invalidate(net);
846 mod_timer(&net->ipv4.rt_secret_timer, jiffies + ip_rt_secret_interval);
847 }
848
849 /*
850 Short description of GC goals.
851
852 We want to build algorithm, which will keep routing cache
853 at some equilibrium point, when number of aged off entries
854 is kept approximately equal to newly generated ones.
855
856 Current expiration strength is variable "expire".
857 We try to adjust it dynamically, so that if networking
858 is idle expires is large enough to keep enough of warm entries,
859 and when load increases it reduces to limit cache size.
860 */
861
862 static int rt_garbage_collect(struct dst_ops *ops)
863 {
864 static unsigned long expire = RT_GC_TIMEOUT;
865 static unsigned long last_gc;
866 static int rover;
867 static int equilibrium;
868 struct rtable *rth, **rthp;
869 unsigned long now = jiffies;
870 int goal;
871
872 /*
873 * Garbage collection is pretty expensive,
874 * do not make it too frequently.
875 */
876
877 RT_CACHE_STAT_INC(gc_total);
878
879 if (now - last_gc < ip_rt_gc_min_interval &&
880 atomic_read(&ipv4_dst_ops.entries) < ip_rt_max_size) {
881 RT_CACHE_STAT_INC(gc_ignored);
882 goto out;
883 }
884
885 /* Calculate number of entries, which we want to expire now. */
886 goal = atomic_read(&ipv4_dst_ops.entries) -
887 (ip_rt_gc_elasticity << rt_hash_log);
888 if (goal <= 0) {
889 if (equilibrium < ipv4_dst_ops.gc_thresh)
890 equilibrium = ipv4_dst_ops.gc_thresh;
891 goal = atomic_read(&ipv4_dst_ops.entries) - equilibrium;
892 if (goal > 0) {
893 equilibrium += min_t(unsigned int, goal >> 1, rt_hash_mask + 1);
894 goal = atomic_read(&ipv4_dst_ops.entries) - equilibrium;
895 }
896 } else {
897 /* We are in dangerous area. Try to reduce cache really
898 * aggressively.
899 */
900 goal = max_t(unsigned int, goal >> 1, rt_hash_mask + 1);
901 equilibrium = atomic_read(&ipv4_dst_ops.entries) - goal;
902 }
903
904 if (now - last_gc >= ip_rt_gc_min_interval)
905 last_gc = now;
906
907 if (goal <= 0) {
908 equilibrium += goal;
909 goto work_done;
910 }
911
912 do {
913 int i, k;
914
915 for (i = rt_hash_mask, k = rover; i >= 0; i--) {
916 unsigned long tmo = expire;
917
918 k = (k + 1) & rt_hash_mask;
919 rthp = &rt_hash_table[k].chain;
920 spin_lock_bh(rt_hash_lock_addr(k));
921 while ((rth = *rthp) != NULL) {
922 if (!rt_is_expired(rth) &&
923 !rt_may_expire(rth, tmo, expire)) {
924 tmo >>= 1;
925 rthp = &rth->u.dst.rt_next;
926 continue;
927 }
928 *rthp = rth->u.dst.rt_next;
929 rt_free(rth);
930 goal--;
931 }
932 spin_unlock_bh(rt_hash_lock_addr(k));
933 if (goal <= 0)
934 break;
935 }
936 rover = k;
937
938 if (goal <= 0)
939 goto work_done;
940
941 /* Goal is not achieved. We stop process if:
942
943 - if expire reduced to zero. Otherwise, expire is halfed.
944 - if table is not full.
945 - if we are called from interrupt.
946 - jiffies check is just fallback/debug loop breaker.
947 We will not spin here for long time in any case.
948 */
949
950 RT_CACHE_STAT_INC(gc_goal_miss);
951
952 if (expire == 0)
953 break;
954
955 expire >>= 1;
956 #if RT_CACHE_DEBUG >= 2
957 printk(KERN_DEBUG "expire>> %u %d %d %d\n", expire,
958 atomic_read(&ipv4_dst_ops.entries), goal, i);
959 #endif
960
961 if (atomic_read(&ipv4_dst_ops.entries) < ip_rt_max_size)
962 goto out;
963 } while (!in_softirq() && time_before_eq(jiffies, now));
964
965 if (atomic_read(&ipv4_dst_ops.entries) < ip_rt_max_size)
966 goto out;
967 if (net_ratelimit())
968 printk(KERN_WARNING "dst cache overflow\n");
969 RT_CACHE_STAT_INC(gc_dst_overflow);
970 return 1;
971
972 work_done:
973 expire += ip_rt_gc_min_interval;
974 if (expire > ip_rt_gc_timeout ||
975 atomic_read(&ipv4_dst_ops.entries) < ipv4_dst_ops.gc_thresh)
976 expire = ip_rt_gc_timeout;
977 #if RT_CACHE_DEBUG >= 2
978 printk(KERN_DEBUG "expire++ %u %d %d %d\n", expire,
979 atomic_read(&ipv4_dst_ops.entries), goal, rover);
980 #endif
981 out: return 0;
982 }
983
984 static int rt_intern_hash(unsigned hash, struct rtable *rt, struct rtable **rp)
985 {
986 struct rtable *rth, **rthp;
987 unsigned long now;
988 struct rtable *cand, **candp;
989 u32 min_score;
990 int chain_length;
991 int attempts = !in_softirq();
992
993 restart:
994 chain_length = 0;
995 min_score = ~(u32)0;
996 cand = NULL;
997 candp = NULL;
998 now = jiffies;
999
1000 rthp = &rt_hash_table[hash].chain;
1001
1002 spin_lock_bh(rt_hash_lock_addr(hash));
1003 while ((rth = *rthp) != NULL) {
1004 if (rt_is_expired(rth)) {
1005 *rthp = rth->u.dst.rt_next;
1006 rt_free(rth);
1007 continue;
1008 }
1009 if (compare_keys(&rth->fl, &rt->fl) && compare_netns(rth, rt)) {
1010 /* Put it first */
1011 *rthp = rth->u.dst.rt_next;
1012 /*
1013 * Since lookup is lockfree, the deletion
1014 * must be visible to another weakly ordered CPU before
1015 * the insertion at the start of the hash chain.
1016 */
1017 rcu_assign_pointer(rth->u.dst.rt_next,
1018 rt_hash_table[hash].chain);
1019 /*
1020 * Since lookup is lockfree, the update writes
1021 * must be ordered for consistency on SMP.
1022 */
1023 rcu_assign_pointer(rt_hash_table[hash].chain, rth);
1024
1025 dst_use(&rth->u.dst, now);
1026 spin_unlock_bh(rt_hash_lock_addr(hash));
1027
1028 rt_drop(rt);
1029 *rp = rth;
1030 return 0;
1031 }
1032
1033 if (!atomic_read(&rth->u.dst.__refcnt)) {
1034 u32 score = rt_score(rth);
1035
1036 if (score <= min_score) {
1037 cand = rth;
1038 candp = rthp;
1039 min_score = score;
1040 }
1041 }
1042
1043 chain_length++;
1044
1045 rthp = &rth->u.dst.rt_next;
1046 }
1047
1048 if (cand) {
1049 /* ip_rt_gc_elasticity used to be average length of chain
1050 * length, when exceeded gc becomes really aggressive.
1051 *
1052 * The second limit is less certain. At the moment it allows
1053 * only 2 entries per bucket. We will see.
1054 */
1055 if (chain_length > ip_rt_gc_elasticity) {
1056 *candp = cand->u.dst.rt_next;
1057 rt_free(cand);
1058 }
1059 }
1060
1061 /* Try to bind route to arp only if it is output
1062 route or unicast forwarding path.
1063 */
1064 if (rt->rt_type == RTN_UNICAST || rt->fl.iif == 0) {
1065 int err = arp_bind_neighbour(&rt->u.dst);
1066 if (err) {
1067 spin_unlock_bh(rt_hash_lock_addr(hash));
1068
1069 if (err != -ENOBUFS) {
1070 rt_drop(rt);
1071 return err;
1072 }
1073
1074 /* Neighbour tables are full and nothing
1075 can be released. Try to shrink route cache,
1076 it is most likely it holds some neighbour records.
1077 */
1078 if (attempts-- > 0) {
1079 int saved_elasticity = ip_rt_gc_elasticity;
1080 int saved_int = ip_rt_gc_min_interval;
1081 ip_rt_gc_elasticity = 1;
1082 ip_rt_gc_min_interval = 0;
1083 rt_garbage_collect(&ipv4_dst_ops);
1084 ip_rt_gc_min_interval = saved_int;
1085 ip_rt_gc_elasticity = saved_elasticity;
1086 goto restart;
1087 }
1088
1089 if (net_ratelimit())
1090 printk(KERN_WARNING "Neighbour table overflow.\n");
1091 rt_drop(rt);
1092 return -ENOBUFS;
1093 }
1094 }
1095
1096 rt->u.dst.rt_next = rt_hash_table[hash].chain;
1097 #if RT_CACHE_DEBUG >= 2
1098 if (rt->u.dst.rt_next) {
1099 struct rtable *trt;
1100 printk(KERN_DEBUG "rt_cache @%02x: " NIPQUAD_FMT, hash,
1101 NIPQUAD(rt->rt_dst));
1102 for (trt = rt->u.dst.rt_next; trt; trt = trt->u.dst.rt_next)
1103 printk(" . " NIPQUAD_FMT, NIPQUAD(trt->rt_dst));
1104 printk("\n");
1105 }
1106 #endif
1107 rt_hash_table[hash].chain = rt;
1108 spin_unlock_bh(rt_hash_lock_addr(hash));
1109 *rp = rt;
1110 return 0;
1111 }
1112
1113 void rt_bind_peer(struct rtable *rt, int create)
1114 {
1115 static DEFINE_SPINLOCK(rt_peer_lock);
1116 struct inet_peer *peer;
1117
1118 peer = inet_getpeer(rt->rt_dst, create);
1119
1120 spin_lock_bh(&rt_peer_lock);
1121 if (rt->peer == NULL) {
1122 rt->peer = peer;
1123 peer = NULL;
1124 }
1125 spin_unlock_bh(&rt_peer_lock);
1126 if (peer)
1127 inet_putpeer(peer);
1128 }
1129
1130 /*
1131 * Peer allocation may fail only in serious out-of-memory conditions. However
1132 * we still can generate some output.
1133 * Random ID selection looks a bit dangerous because we have no chances to
1134 * select ID being unique in a reasonable period of time.
1135 * But broken packet identifier may be better than no packet at all.
1136 */
1137 static void ip_select_fb_ident(struct iphdr *iph)
1138 {
1139 static DEFINE_SPINLOCK(ip_fb_id_lock);
1140 static u32 ip_fallback_id;
1141 u32 salt;
1142
1143 spin_lock_bh(&ip_fb_id_lock);
1144 salt = secure_ip_id((__force __be32)ip_fallback_id ^ iph->daddr);
1145 iph->id = htons(salt & 0xFFFF);
1146 ip_fallback_id = salt;
1147 spin_unlock_bh(&ip_fb_id_lock);
1148 }
1149
1150 void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more)
1151 {
1152 struct rtable *rt = (struct rtable *) dst;
1153
1154 if (rt) {
1155 if (rt->peer == NULL)
1156 rt_bind_peer(rt, 1);
1157
1158 /* If peer is attached to destination, it is never detached,
1159 so that we need not to grab a lock to dereference it.
1160 */
1161 if (rt->peer) {
1162 iph->id = htons(inet_getid(rt->peer, more));
1163 return;
1164 }
1165 } else
1166 printk(KERN_DEBUG "rt_bind_peer(0) @%p\n",
1167 __builtin_return_address(0));
1168
1169 ip_select_fb_ident(iph);
1170 }
1171
1172 static void rt_del(unsigned hash, struct rtable *rt)
1173 {
1174 struct rtable **rthp, *aux;
1175
1176 rthp = &rt_hash_table[hash].chain;
1177 spin_lock_bh(rt_hash_lock_addr(hash));
1178 ip_rt_put(rt);
1179 while ((aux = *rthp) != NULL) {
1180 if (aux == rt || rt_is_expired(aux)) {
1181 *rthp = aux->u.dst.rt_next;
1182 rt_free(aux);
1183 continue;
1184 }
1185 rthp = &aux->u.dst.rt_next;
1186 }
1187 spin_unlock_bh(rt_hash_lock_addr(hash));
1188 }
1189
1190 void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw,
1191 __be32 saddr, struct net_device *dev)
1192 {
1193 int i, k;
1194 struct in_device *in_dev = in_dev_get(dev);
1195 struct rtable *rth, **rthp;
1196 __be32 skeys[2] = { saddr, 0 };
1197 int ikeys[2] = { dev->ifindex, 0 };
1198 struct netevent_redirect netevent;
1199 struct net *net;
1200
1201 if (!in_dev)
1202 return;
1203
1204 net = dev_net(dev);
1205 if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev)
1206 || ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw)
1207 || ipv4_is_zeronet(new_gw))
1208 goto reject_redirect;
1209
1210 if (!IN_DEV_SHARED_MEDIA(in_dev)) {
1211 if (!inet_addr_onlink(in_dev, new_gw, old_gw))
1212 goto reject_redirect;
1213 if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev))
1214 goto reject_redirect;
1215 } else {
1216 if (inet_addr_type(net, new_gw) != RTN_UNICAST)
1217 goto reject_redirect;
1218 }
1219
1220 for (i = 0; i < 2; i++) {
1221 for (k = 0; k < 2; k++) {
1222 unsigned hash = rt_hash(daddr, skeys[i], ikeys[k],
1223 rt_genid(net));
1224
1225 rthp=&rt_hash_table[hash].chain;
1226
1227 rcu_read_lock();
1228 while ((rth = rcu_dereference(*rthp)) != NULL) {
1229 struct rtable *rt;
1230
1231 if (rth->fl.fl4_dst != daddr ||
1232 rth->fl.fl4_src != skeys[i] ||
1233 rth->fl.oif != ikeys[k] ||
1234 rth->fl.iif != 0 ||
1235 rt_is_expired(rth) ||
1236 !net_eq(dev_net(rth->u.dst.dev), net)) {
1237 rthp = &rth->u.dst.rt_next;
1238 continue;
1239 }
1240
1241 if (rth->rt_dst != daddr ||
1242 rth->rt_src != saddr ||
1243 rth->u.dst.error ||
1244 rth->rt_gateway != old_gw ||
1245 rth->u.dst.dev != dev)
1246 break;
1247
1248 dst_hold(&rth->u.dst);
1249 rcu_read_unlock();
1250
1251 rt = dst_alloc(&ipv4_dst_ops);
1252 if (rt == NULL) {
1253 ip_rt_put(rth);
1254 in_dev_put(in_dev);
1255 return;
1256 }
1257
1258 /* Copy all the information. */
1259 *rt = *rth;
1260 INIT_RCU_HEAD(&rt->u.dst.rcu_head);
1261 rt->u.dst.__use = 1;
1262 atomic_set(&rt->u.dst.__refcnt, 1);
1263 rt->u.dst.child = NULL;
1264 if (rt->u.dst.dev)
1265 dev_hold(rt->u.dst.dev);
1266 if (rt->idev)
1267 in_dev_hold(rt->idev);
1268 rt->u.dst.obsolete = 0;
1269 rt->u.dst.lastuse = jiffies;
1270 rt->u.dst.path = &rt->u.dst;
1271 rt->u.dst.neighbour = NULL;
1272 rt->u.dst.hh = NULL;
1273 rt->u.dst.xfrm = NULL;
1274 rt->rt_genid = rt_genid(net);
1275 rt->rt_flags |= RTCF_REDIRECTED;
1276
1277 /* Gateway is different ... */
1278 rt->rt_gateway = new_gw;
1279
1280 /* Redirect received -> path was valid */
1281 dst_confirm(&rth->u.dst);
1282
1283 if (rt->peer)
1284 atomic_inc(&rt->peer->refcnt);
1285
1286 if (arp_bind_neighbour(&rt->u.dst) ||
1287 !(rt->u.dst.neighbour->nud_state &
1288 NUD_VALID)) {
1289 if (rt->u.dst.neighbour)
1290 neigh_event_send(rt->u.dst.neighbour, NULL);
1291 ip_rt_put(rth);
1292 rt_drop(rt);
1293 goto do_next;
1294 }
1295
1296 netevent.old = &rth->u.dst;
1297 netevent.new = &rt->u.dst;
1298 call_netevent_notifiers(NETEVENT_REDIRECT,
1299 &netevent);
1300
1301 rt_del(hash, rth);
1302 if (!rt_intern_hash(hash, rt, &rt))
1303 ip_rt_put(rt);
1304 goto do_next;
1305 }
1306 rcu_read_unlock();
1307 do_next:
1308 ;
1309 }
1310 }
1311 in_dev_put(in_dev);
1312 return;
1313
1314 reject_redirect:
1315 #ifdef CONFIG_IP_ROUTE_VERBOSE
1316 if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit())
1317 printk(KERN_INFO "Redirect from " NIPQUAD_FMT " on %s about "
1318 NIPQUAD_FMT " ignored.\n"
1319 " Advised path = " NIPQUAD_FMT " -> " NIPQUAD_FMT "\n",
1320 NIPQUAD(old_gw), dev->name, NIPQUAD(new_gw),
1321 NIPQUAD(saddr), NIPQUAD(daddr));
1322 #endif
1323 in_dev_put(in_dev);
1324 }
1325
1326 static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
1327 {
1328 struct rtable *rt = (struct rtable *)dst;
1329 struct dst_entry *ret = dst;
1330
1331 if (rt) {
1332 if (dst->obsolete) {
1333 ip_rt_put(rt);
1334 ret = NULL;
1335 } else if ((rt->rt_flags & RTCF_REDIRECTED) ||
1336 rt->u.dst.expires) {
1337 unsigned hash = rt_hash(rt->fl.fl4_dst, rt->fl.fl4_src,
1338 rt->fl.oif,
1339 rt_genid(dev_net(dst->dev)));
1340 #if RT_CACHE_DEBUG >= 1
1341 printk(KERN_DEBUG "ipv4_negative_advice: redirect to "
1342 NIPQUAD_FMT "/%02x dropped\n",
1343 NIPQUAD(rt->rt_dst), rt->fl.fl4_tos);
1344 #endif
1345 rt_del(hash, rt);
1346 ret = NULL;
1347 }
1348 }
1349 return ret;
1350 }
1351
1352 /*
1353 * Algorithm:
1354 * 1. The first ip_rt_redirect_number redirects are sent
1355 * with exponential backoff, then we stop sending them at all,
1356 * assuming that the host ignores our redirects.
1357 * 2. If we did not see packets requiring redirects
1358 * during ip_rt_redirect_silence, we assume that the host
1359 * forgot redirected route and start to send redirects again.
1360 *
1361 * This algorithm is much cheaper and more intelligent than dumb load limiting
1362 * in icmp.c.
1363 *
1364 * NOTE. Do not forget to inhibit load limiting for redirects (redundant)
1365 * and "frag. need" (breaks PMTU discovery) in icmp.c.
1366 */
1367
1368 void ip_rt_send_redirect(struct sk_buff *skb)
1369 {
1370 struct rtable *rt = skb->rtable;
1371 struct in_device *in_dev = in_dev_get(rt->u.dst.dev);
1372
1373 if (!in_dev)
1374 return;
1375
1376 if (!IN_DEV_TX_REDIRECTS(in_dev))
1377 goto out;
1378
1379 /* No redirected packets during ip_rt_redirect_silence;
1380 * reset the algorithm.
1381 */
1382 if (time_after(jiffies, rt->u.dst.rate_last + ip_rt_redirect_silence))
1383 rt->u.dst.rate_tokens = 0;
1384
1385 /* Too many ignored redirects; do not send anything
1386 * set u.dst.rate_last to the last seen redirected packet.
1387 */
1388 if (rt->u.dst.rate_tokens >= ip_rt_redirect_number) {
1389 rt->u.dst.rate_last = jiffies;
1390 goto out;
1391 }
1392
1393 /* Check for load limit; set rate_last to the latest sent
1394 * redirect.
1395 */
1396 if (rt->u.dst.rate_tokens == 0 ||
1397 time_after(jiffies,
1398 (rt->u.dst.rate_last +
1399 (ip_rt_redirect_load << rt->u.dst.rate_tokens)))) {
1400 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway);
1401 rt->u.dst.rate_last = jiffies;
1402 ++rt->u.dst.rate_tokens;
1403 #ifdef CONFIG_IP_ROUTE_VERBOSE
1404 if (IN_DEV_LOG_MARTIANS(in_dev) &&
1405 rt->u.dst.rate_tokens == ip_rt_redirect_number &&
1406 net_ratelimit())
1407 printk(KERN_WARNING "host " NIPQUAD_FMT "/if%d ignores "
1408 "redirects for " NIPQUAD_FMT " to " NIPQUAD_FMT ".\n",
1409 NIPQUAD(rt->rt_src), rt->rt_iif,
1410 NIPQUAD(rt->rt_dst), NIPQUAD(rt->rt_gateway));
1411 #endif
1412 }
1413 out:
1414 in_dev_put(in_dev);
1415 }
1416
1417 static int ip_error(struct sk_buff *skb)
1418 {
1419 struct rtable *rt = skb->rtable;
1420 unsigned long now;
1421 int code;
1422
1423 switch (rt->u.dst.error) {
1424 case EINVAL:
1425 default:
1426 goto out;
1427 case EHOSTUNREACH:
1428 code = ICMP_HOST_UNREACH;
1429 break;
1430 case ENETUNREACH:
1431 code = ICMP_NET_UNREACH;
1432 IP_INC_STATS_BH(IPSTATS_MIB_INNOROUTES);
1433 break;
1434 case EACCES:
1435 code = ICMP_PKT_FILTERED;
1436 break;
1437 }
1438
1439 now = jiffies;
1440 rt->u.dst.rate_tokens += now - rt->u.dst.rate_last;
1441 if (rt->u.dst.rate_tokens > ip_rt_error_burst)
1442 rt->u.dst.rate_tokens = ip_rt_error_burst;
1443 rt->u.dst.rate_last = now;
1444 if (rt->u.dst.rate_tokens >= ip_rt_error_cost) {
1445 rt->u.dst.rate_tokens -= ip_rt_error_cost;
1446 icmp_send(skb, ICMP_DEST_UNREACH, code, 0);
1447 }
1448
1449 out: kfree_skb(skb);
1450 return 0;
1451 }
1452
1453 /*
1454 * The last two values are not from the RFC but
1455 * are needed for AMPRnet AX.25 paths.
1456 */
1457
1458 static const unsigned short mtu_plateau[] =
1459 {32000, 17914, 8166, 4352, 2002, 1492, 576, 296, 216, 128 };
1460
1461 static inline unsigned short guess_mtu(unsigned short old_mtu)
1462 {
1463 int i;
1464
1465 for (i = 0; i < ARRAY_SIZE(mtu_plateau); i++)
1466 if (old_mtu > mtu_plateau[i])
1467 return mtu_plateau[i];
1468 return 68;
1469 }
1470
1471 unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph,
1472 unsigned short new_mtu,
1473 struct net_device *dev)
1474 {
1475 int i, k;
1476 unsigned short old_mtu = ntohs(iph->tot_len);
1477 struct rtable *rth;
1478 int ikeys[2] = { dev->ifindex, 0 };
1479 __be32 skeys[2] = { iph->saddr, 0, };
1480 __be32 daddr = iph->daddr;
1481 unsigned short est_mtu = 0;
1482
1483 if (ipv4_config.no_pmtu_disc)
1484 return 0;
1485
1486 for (k = 0; k < 2; k++) {
1487 for (i = 0; i < 2; i++) {
1488 unsigned hash = rt_hash(daddr, skeys[i], ikeys[k],
1489 rt_genid(net));
1490
1491 rcu_read_lock();
1492 for (rth = rcu_dereference(rt_hash_table[hash].chain); rth;
1493 rth = rcu_dereference(rth->u.dst.rt_next)) {
1494 unsigned short mtu = new_mtu;
1495
1496 if (rth->fl.fl4_dst != daddr ||
1497 rth->fl.fl4_src != skeys[i] ||
1498 rth->rt_dst != daddr ||
1499 rth->rt_src != iph->saddr ||
1500 rth->fl.oif != ikeys[k] ||
1501 rth->fl.iif != 0 ||
1502 dst_metric_locked(&rth->u.dst, RTAX_MTU) ||
1503 !net_eq(dev_net(rth->u.dst.dev), net) ||
1504 !rt_is_expired(rth))
1505 continue;
1506
1507 if (new_mtu < 68 || new_mtu >= old_mtu) {
1508
1509 /* BSD 4.2 compatibility hack :-( */
1510 if (mtu == 0 &&
1511 old_mtu >= dst_metric(&rth->u.dst, RTAX_MTU) &&
1512 old_mtu >= 68 + (iph->ihl << 2))
1513 old_mtu -= iph->ihl << 2;
1514
1515 mtu = guess_mtu(old_mtu);
1516 }
1517 if (mtu <= dst_metric(&rth->u.dst, RTAX_MTU)) {
1518 if (mtu < dst_metric(&rth->u.dst, RTAX_MTU)) {
1519 dst_confirm(&rth->u.dst);
1520 if (mtu < ip_rt_min_pmtu) {
1521 mtu = ip_rt_min_pmtu;
1522 rth->u.dst.metrics[RTAX_LOCK-1] |=
1523 (1 << RTAX_MTU);
1524 }
1525 rth->u.dst.metrics[RTAX_MTU-1] = mtu;
1526 dst_set_expires(&rth->u.dst,
1527 ip_rt_mtu_expires);
1528 }
1529 est_mtu = mtu;
1530 }
1531 }
1532 rcu_read_unlock();
1533 }
1534 }
1535 return est_mtu ? : new_mtu;
1536 }
1537
1538 static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
1539 {
1540 if (dst_metric(dst, RTAX_MTU) > mtu && mtu >= 68 &&
1541 !(dst_metric_locked(dst, RTAX_MTU))) {
1542 if (mtu < ip_rt_min_pmtu) {
1543 mtu = ip_rt_min_pmtu;
1544 dst->metrics[RTAX_LOCK-1] |= (1 << RTAX_MTU);
1545 }
1546 dst->metrics[RTAX_MTU-1] = mtu;
1547 dst_set_expires(dst, ip_rt_mtu_expires);
1548 call_netevent_notifiers(NETEVENT_PMTU_UPDATE, dst);
1549 }
1550 }
1551
1552 static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
1553 {
1554 return NULL;
1555 }
1556
1557 static void ipv4_dst_destroy(struct dst_entry *dst)
1558 {
1559 struct rtable *rt = (struct rtable *) dst;
1560 struct inet_peer *peer = rt->peer;
1561 struct in_device *idev = rt->idev;
1562
1563 if (peer) {
1564 rt->peer = NULL;
1565 inet_putpeer(peer);
1566 }
1567
1568 if (idev) {
1569 rt->idev = NULL;
1570 in_dev_put(idev);
1571 }
1572 }
1573
1574 static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
1575 int how)
1576 {
1577 struct rtable *rt = (struct rtable *) dst;
1578 struct in_device *idev = rt->idev;
1579 if (dev != dev_net(dev)->loopback_dev && idev && idev->dev == dev) {
1580 struct in_device *loopback_idev =
1581 in_dev_get(dev_net(dev)->loopback_dev);
1582 if (loopback_idev) {
1583 rt->idev = loopback_idev;
1584 in_dev_put(idev);
1585 }
1586 }
1587 }
1588
1589 static void ipv4_link_failure(struct sk_buff *skb)
1590 {
1591 struct rtable *rt;
1592
1593 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
1594
1595 rt = skb->rtable;
1596 if (rt)
1597 dst_set_expires(&rt->u.dst, 0);
1598 }
1599
1600 static int ip_rt_bug(struct sk_buff *skb)
1601 {
1602 printk(KERN_DEBUG "ip_rt_bug: " NIPQUAD_FMT " -> " NIPQUAD_FMT ", %s\n",
1603 NIPQUAD(ip_hdr(skb)->saddr), NIPQUAD(ip_hdr(skb)->daddr),
1604 skb->dev ? skb->dev->name : "?");
1605 kfree_skb(skb);
1606 return 0;
1607 }
1608
1609 /*
1610 We do not cache source address of outgoing interface,
1611 because it is used only by IP RR, TS and SRR options,
1612 so that it out of fast path.
1613
1614 BTW remember: "addr" is allowed to be not aligned
1615 in IP options!
1616 */
1617
1618 void ip_rt_get_source(u8 *addr, struct rtable *rt)
1619 {
1620 __be32 src;
1621 struct fib_result res;
1622
1623 if (rt->fl.iif == 0)
1624 src = rt->rt_src;
1625 else if (fib_lookup(dev_net(rt->u.dst.dev), &rt->fl, &res) == 0) {
1626 src = FIB_RES_PREFSRC(res);
1627 fib_res_put(&res);
1628 } else
1629 src = inet_select_addr(rt->u.dst.dev, rt->rt_gateway,
1630 RT_SCOPE_UNIVERSE);
1631 memcpy(addr, &src, 4);
1632 }
1633
1634 #ifdef CONFIG_NET_CLS_ROUTE
1635 static void set_class_tag(struct rtable *rt, u32 tag)
1636 {
1637 if (!(rt->u.dst.tclassid & 0xFFFF))
1638 rt->u.dst.tclassid |= tag & 0xFFFF;
1639 if (!(rt->u.dst.tclassid & 0xFFFF0000))
1640 rt->u.dst.tclassid |= tag & 0xFFFF0000;
1641 }
1642 #endif
1643
1644 static void rt_set_nexthop(struct rtable *rt, struct fib_result *res, u32 itag)
1645 {
1646 struct fib_info *fi = res->fi;
1647
1648 if (fi) {
1649 if (FIB_RES_GW(*res) &&
1650 FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
1651 rt->rt_gateway = FIB_RES_GW(*res);
1652 memcpy(rt->u.dst.metrics, fi->fib_metrics,
1653 sizeof(rt->u.dst.metrics));
1654 if (fi->fib_mtu == 0) {
1655 rt->u.dst.metrics[RTAX_MTU-1] = rt->u.dst.dev->mtu;
1656 if (dst_metric_locked(&rt->u.dst, RTAX_MTU) &&
1657 rt->rt_gateway != rt->rt_dst &&
1658 rt->u.dst.dev->mtu > 576)
1659 rt->u.dst.metrics[RTAX_MTU-1] = 576;
1660 }
1661 #ifdef CONFIG_NET_CLS_ROUTE
1662 rt->u.dst.tclassid = FIB_RES_NH(*res).nh_tclassid;
1663 #endif
1664 } else
1665 rt->u.dst.metrics[RTAX_MTU-1]= rt->u.dst.dev->mtu;
1666
1667 if (dst_metric(&rt->u.dst, RTAX_HOPLIMIT) == 0)
1668 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = sysctl_ip_default_ttl;
1669 if (dst_metric(&rt->u.dst, RTAX_MTU) > IP_MAX_MTU)
1670 rt->u.dst.metrics[RTAX_MTU-1] = IP_MAX_MTU;
1671 if (dst_metric(&rt->u.dst, RTAX_ADVMSS) == 0)
1672 rt->u.dst.metrics[RTAX_ADVMSS-1] = max_t(unsigned int, rt->u.dst.dev->mtu - 40,
1673 ip_rt_min_advmss);
1674 if (dst_metric(&rt->u.dst, RTAX_ADVMSS) > 65535 - 40)
1675 rt->u.dst.metrics[RTAX_ADVMSS-1] = 65535 - 40;
1676
1677 #ifdef CONFIG_NET_CLS_ROUTE
1678 #ifdef CONFIG_IP_MULTIPLE_TABLES
1679 set_class_tag(rt, fib_rules_tclass(res));
1680 #endif
1681 set_class_tag(rt, itag);
1682 #endif
1683 rt->rt_type = res->type;
1684 }
1685
1686 static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1687 u8 tos, struct net_device *dev, int our)
1688 {
1689 unsigned hash;
1690 struct rtable *rth;
1691 __be32 spec_dst;
1692 struct in_device *in_dev = in_dev_get(dev);
1693 u32 itag = 0;
1694
1695 /* Primary sanity checks. */
1696
1697 if (in_dev == NULL)
1698 return -EINVAL;
1699
1700 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) ||
1701 ipv4_is_loopback(saddr) || skb->protocol != htons(ETH_P_IP))
1702 goto e_inval;
1703
1704 if (ipv4_is_zeronet(saddr)) {
1705 if (!ipv4_is_local_multicast(daddr))
1706 goto e_inval;
1707 spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK);
1708 } else if (fib_validate_source(saddr, 0, tos, 0,
1709 dev, &spec_dst, &itag) < 0)
1710 goto e_inval;
1711
1712 rth = dst_alloc(&ipv4_dst_ops);
1713 if (!rth)
1714 goto e_nobufs;
1715
1716 rth->u.dst.output= ip_rt_bug;
1717
1718 atomic_set(&rth->u.dst.__refcnt, 1);
1719 rth->u.dst.flags= DST_HOST;
1720 if (IN_DEV_CONF_GET(in_dev, NOPOLICY))
1721 rth->u.dst.flags |= DST_NOPOLICY;
1722 rth->fl.fl4_dst = daddr;
1723 rth->rt_dst = daddr;
1724 rth->fl.fl4_tos = tos;
1725 rth->fl.mark = skb->mark;
1726 rth->fl.fl4_src = saddr;
1727 rth->rt_src = saddr;
1728 #ifdef CONFIG_NET_CLS_ROUTE
1729 rth->u.dst.tclassid = itag;
1730 #endif
1731 rth->rt_iif =
1732 rth->fl.iif = dev->ifindex;
1733 rth->u.dst.dev = init_net.loopback_dev;
1734 dev_hold(rth->u.dst.dev);
1735 rth->idev = in_dev_get(rth->u.dst.dev);
1736 rth->fl.oif = 0;
1737 rth->rt_gateway = daddr;
1738 rth->rt_spec_dst= spec_dst;
1739 rth->rt_genid = rt_genid(dev_net(dev));
1740 rth->rt_flags = RTCF_MULTICAST;
1741 rth->rt_type = RTN_MULTICAST;
1742 if (our) {
1743 rth->u.dst.input= ip_local_deliver;
1744 rth->rt_flags |= RTCF_LOCAL;
1745 }
1746
1747 #ifdef CONFIG_IP_MROUTE
1748 if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev))
1749 rth->u.dst.input = ip_mr_input;
1750 #endif
1751 RT_CACHE_STAT_INC(in_slow_mc);
1752
1753 in_dev_put(in_dev);
1754 hash = rt_hash(daddr, saddr, dev->ifindex, rt_genid(dev_net(dev)));
1755 return rt_intern_hash(hash, rth, &skb->rtable);
1756
1757 e_nobufs:
1758 in_dev_put(in_dev);
1759 return -ENOBUFS;
1760
1761 e_inval:
1762 in_dev_put(in_dev);
1763 return -EINVAL;
1764 }
1765
1766
1767 static void ip_handle_martian_source(struct net_device *dev,
1768 struct in_device *in_dev,
1769 struct sk_buff *skb,
1770 __be32 daddr,
1771 __be32 saddr)
1772 {
1773 RT_CACHE_STAT_INC(in_martian_src);
1774 #ifdef CONFIG_IP_ROUTE_VERBOSE
1775 if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) {
1776 /*
1777 * RFC1812 recommendation, if source is martian,
1778 * the only hint is MAC header.
1779 */
1780 printk(KERN_WARNING "martian source " NIPQUAD_FMT " from "
1781 NIPQUAD_FMT", on dev %s\n",
1782 NIPQUAD(daddr), NIPQUAD(saddr), dev->name);
1783 if (dev->hard_header_len && skb_mac_header_was_set(skb)) {
1784 int i;
1785 const unsigned char *p = skb_mac_header(skb);
1786 printk(KERN_WARNING "ll header: ");
1787 for (i = 0; i < dev->hard_header_len; i++, p++) {
1788 printk("%02x", *p);
1789 if (i < (dev->hard_header_len - 1))
1790 printk(":");
1791 }
1792 printk("\n");
1793 }
1794 }
1795 #endif
1796 }
1797
1798 static int __mkroute_input(struct sk_buff *skb,
1799 struct fib_result *res,
1800 struct in_device *in_dev,
1801 __be32 daddr, __be32 saddr, u32 tos,
1802 struct rtable **result)
1803 {
1804
1805 struct rtable *rth;
1806 int err;
1807 struct in_device *out_dev;
1808 unsigned flags = 0;
1809 __be32 spec_dst;
1810 u32 itag;
1811
1812 /* get a working reference to the output device */
1813 out_dev = in_dev_get(FIB_RES_DEV(*res));
1814 if (out_dev == NULL) {
1815 if (net_ratelimit())
1816 printk(KERN_CRIT "Bug in ip_route_input" \
1817 "_slow(). Please, report\n");
1818 return -EINVAL;
1819 }
1820
1821
1822 err = fib_validate_source(saddr, daddr, tos, FIB_RES_OIF(*res),
1823 in_dev->dev, &spec_dst, &itag);
1824 if (err < 0) {
1825 ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr,
1826 saddr);
1827
1828 err = -EINVAL;
1829 goto cleanup;
1830 }
1831
1832 if (err)
1833 flags |= RTCF_DIRECTSRC;
1834
1835 if (out_dev == in_dev && err &&
1836 (IN_DEV_SHARED_MEDIA(out_dev) ||
1837 inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res))))
1838 flags |= RTCF_DOREDIRECT;
1839
1840 if (skb->protocol != htons(ETH_P_IP)) {
1841 /* Not IP (i.e. ARP). Do not create route, if it is
1842 * invalid for proxy arp. DNAT routes are always valid.
1843 */
1844 if (out_dev == in_dev) {
1845 err = -EINVAL;
1846 goto cleanup;
1847 }
1848 }
1849
1850
1851 rth = dst_alloc(&ipv4_dst_ops);
1852 if (!rth) {
1853 err = -ENOBUFS;
1854 goto cleanup;
1855 }
1856
1857 atomic_set(&rth->u.dst.__refcnt, 1);
1858 rth->u.dst.flags= DST_HOST;
1859 if (IN_DEV_CONF_GET(in_dev, NOPOLICY))
1860 rth->u.dst.flags |= DST_NOPOLICY;
1861 if (IN_DEV_CONF_GET(out_dev, NOXFRM))
1862 rth->u.dst.flags |= DST_NOXFRM;
1863 rth->fl.fl4_dst = daddr;
1864 rth->rt_dst = daddr;
1865 rth->fl.fl4_tos = tos;
1866 rth->fl.mark = skb->mark;
1867 rth->fl.fl4_src = saddr;
1868 rth->rt_src = saddr;
1869 rth->rt_gateway = daddr;
1870 rth->rt_iif =
1871 rth->fl.iif = in_dev->dev->ifindex;
1872 rth->u.dst.dev = (out_dev)->dev;
1873 dev_hold(rth->u.dst.dev);
1874 rth->idev = in_dev_get(rth->u.dst.dev);
1875 rth->fl.oif = 0;
1876 rth->rt_spec_dst= spec_dst;
1877
1878 rth->u.dst.input = ip_forward;
1879 rth->u.dst.output = ip_output;
1880 rth->rt_genid = rt_genid(dev_net(rth->u.dst.dev));
1881
1882 rt_set_nexthop(rth, res, itag);
1883
1884 rth->rt_flags = flags;
1885
1886 *result = rth;
1887 err = 0;
1888 cleanup:
1889 /* release the working reference to the output device */
1890 in_dev_put(out_dev);
1891 return err;
1892 }
1893
1894 static int ip_mkroute_input(struct sk_buff *skb,
1895 struct fib_result *res,
1896 const struct flowi *fl,
1897 struct in_device *in_dev,
1898 __be32 daddr, __be32 saddr, u32 tos)
1899 {
1900 struct rtable* rth = NULL;
1901 int err;
1902 unsigned hash;
1903
1904 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1905 if (res->fi && res->fi->fib_nhs > 1 && fl->oif == 0)
1906 fib_select_multipath(fl, res);
1907 #endif
1908
1909 /* create a routing cache entry */
1910 err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, &rth);
1911 if (err)
1912 return err;
1913
1914 /* put it into the cache */
1915 hash = rt_hash(daddr, saddr, fl->iif,
1916 rt_genid(dev_net(rth->u.dst.dev)));
1917 return rt_intern_hash(hash, rth, &skb->rtable);
1918 }
1919
1920 /*
1921 * NOTE. We drop all the packets that has local source
1922 * addresses, because every properly looped back packet
1923 * must have correct destination already attached by output routine.
1924 *
1925 * Such approach solves two big problems:
1926 * 1. Not simplex devices are handled properly.
1927 * 2. IP spoofing attempts are filtered with 100% of guarantee.
1928 */
1929
1930 static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1931 u8 tos, struct net_device *dev)
1932 {
1933 struct fib_result res;
1934 struct in_device *in_dev = in_dev_get(dev);
1935 struct flowi fl = { .nl_u = { .ip4_u =
1936 { .daddr = daddr,
1937 .saddr = saddr,
1938 .tos = tos,
1939 .scope = RT_SCOPE_UNIVERSE,
1940 } },
1941 .mark = skb->mark,
1942 .iif = dev->ifindex };
1943 unsigned flags = 0;
1944 u32 itag = 0;
1945 struct rtable * rth;
1946 unsigned hash;
1947 __be32 spec_dst;
1948 int err = -EINVAL;
1949 int free_res = 0;
1950 struct net * net = dev_net(dev);
1951
1952 /* IP on this device is disabled. */
1953
1954 if (!in_dev)
1955 goto out;
1956
1957 /* Check for the most weird martians, which can be not detected
1958 by fib_lookup.
1959 */
1960
1961 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) ||
1962 ipv4_is_loopback(saddr))
1963 goto martian_source;
1964
1965 if (daddr == htonl(0xFFFFFFFF) || (saddr == 0 && daddr == 0))
1966 goto brd_input;
1967
1968 /* Accept zero addresses only to limited broadcast;
1969 * I even do not know to fix it or not. Waiting for complains :-)
1970 */
1971 if (ipv4_is_zeronet(saddr))
1972 goto martian_source;
1973
1974 if (ipv4_is_lbcast(daddr) || ipv4_is_zeronet(daddr) ||
1975 ipv4_is_loopback(daddr))
1976 goto martian_destination;
1977
1978 /*
1979 * Now we are ready to route packet.
1980 */
1981 if ((err = fib_lookup(net, &fl, &res)) != 0) {
1982 if (!IN_DEV_FORWARD(in_dev))
1983 goto e_hostunreach;
1984 goto no_route;
1985 }
1986 free_res = 1;
1987
1988 RT_CACHE_STAT_INC(in_slow_tot);
1989
1990 if (res.type == RTN_BROADCAST)
1991 goto brd_input;
1992
1993 if (res.type == RTN_LOCAL) {
1994 int result;
1995 result = fib_validate_source(saddr, daddr, tos,
1996 net->loopback_dev->ifindex,
1997 dev, &spec_dst, &itag);
1998 if (result < 0)
1999 goto martian_source;
2000 if (result)
2001 flags |= RTCF_DIRECTSRC;
2002 spec_dst = daddr;
2003 goto local_input;
2004 }
2005
2006 if (!IN_DEV_FORWARD(in_dev))
2007 goto e_hostunreach;
2008 if (res.type != RTN_UNICAST)
2009 goto martian_destination;
2010
2011 err = ip_mkroute_input(skb, &res, &fl, in_dev, daddr, saddr, tos);
2012 done:
2013 in_dev_put(in_dev);
2014 if (free_res)
2015 fib_res_put(&res);
2016 out: return err;
2017
2018 brd_input:
2019 if (skb->protocol != htons(ETH_P_IP))
2020 goto e_inval;
2021
2022 if (ipv4_is_zeronet(saddr))
2023 spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK);
2024 else {
2025 err = fib_validate_source(saddr, 0, tos, 0, dev, &spec_dst,
2026 &itag);
2027 if (err < 0)
2028 goto martian_source;
2029 if (err)
2030 flags |= RTCF_DIRECTSRC;
2031 }
2032 flags |= RTCF_BROADCAST;
2033 res.type = RTN_BROADCAST;
2034 RT_CACHE_STAT_INC(in_brd);
2035
2036 local_input:
2037 rth = dst_alloc(&ipv4_dst_ops);
2038 if (!rth)
2039 goto e_nobufs;
2040
2041 rth->u.dst.output= ip_rt_bug;
2042 rth->rt_genid = rt_genid(net);
2043
2044 atomic_set(&rth->u.dst.__refcnt, 1);
2045 rth->u.dst.flags= DST_HOST;
2046 if (IN_DEV_CONF_GET(in_dev, NOPOLICY))
2047 rth->u.dst.flags |= DST_NOPOLICY;
2048 rth->fl.fl4_dst = daddr;
2049 rth->rt_dst = daddr;
2050 rth->fl.fl4_tos = tos;
2051 rth->fl.mark = skb->mark;
2052 rth->fl.fl4_src = saddr;
2053 rth->rt_src = saddr;
2054 #ifdef CONFIG_NET_CLS_ROUTE
2055 rth->u.dst.tclassid = itag;
2056 #endif
2057 rth->rt_iif =
2058 rth->fl.iif = dev->ifindex;
2059 rth->u.dst.dev = net->loopback_dev;
2060 dev_hold(rth->u.dst.dev);
2061 rth->idev = in_dev_get(rth->u.dst.dev);
2062 rth->rt_gateway = daddr;
2063 rth->rt_spec_dst= spec_dst;
2064 rth->u.dst.input= ip_local_deliver;
2065 rth->rt_flags = flags|RTCF_LOCAL;
2066 if (res.type == RTN_UNREACHABLE) {
2067 rth->u.dst.input= ip_error;
2068 rth->u.dst.error= -err;
2069 rth->rt_flags &= ~RTCF_LOCAL;
2070 }
2071 rth->rt_type = res.type;
2072 hash = rt_hash(daddr, saddr, fl.iif, rt_genid(net));
2073 err = rt_intern_hash(hash, rth, &skb->rtable);
2074 goto done;
2075
2076 no_route:
2077 RT_CACHE_STAT_INC(in_no_route);
2078 spec_dst = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE);
2079 res.type = RTN_UNREACHABLE;
2080 if (err == -ESRCH)
2081 err = -ENETUNREACH;
2082 goto local_input;
2083
2084 /*
2085 * Do not cache martian addresses: they should be logged (RFC1812)
2086 */
2087 martian_destination:
2088 RT_CACHE_STAT_INC(in_martian_dst);
2089 #ifdef CONFIG_IP_ROUTE_VERBOSE
2090 if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit())
2091 printk(KERN_WARNING "martian destination " NIPQUAD_FMT " from "
2092 NIPQUAD_FMT ", dev %s\n",
2093 NIPQUAD(daddr), NIPQUAD(saddr), dev->name);
2094 #endif
2095
2096 e_hostunreach:
2097 err = -EHOSTUNREACH;
2098 goto done;
2099
2100 e_inval:
2101 err = -EINVAL;
2102 goto done;
2103
2104 e_nobufs:
2105 err = -ENOBUFS;
2106 goto done;
2107
2108 martian_source:
2109 ip_handle_martian_source(dev, in_dev, skb, daddr, saddr);
2110 goto e_inval;
2111 }
2112
2113 int ip_route_input(struct sk_buff *skb, __be32 daddr, __be32 saddr,
2114 u8 tos, struct net_device *dev)
2115 {
2116 struct rtable * rth;
2117 unsigned hash;
2118 int iif = dev->ifindex;
2119 struct net *net;
2120
2121 net = dev_net(dev);
2122 tos &= IPTOS_RT_MASK;
2123 hash = rt_hash(daddr, saddr, iif, rt_genid(net));
2124
2125 rcu_read_lock();
2126 for (rth = rcu_dereference(rt_hash_table[hash].chain); rth;
2127 rth = rcu_dereference(rth->u.dst.rt_next)) {
2128 if (((rth->fl.fl4_dst ^ daddr) |
2129 (rth->fl.fl4_src ^ saddr) |
2130 (rth->fl.iif ^ iif) |
2131 rth->fl.oif |
2132 (rth->fl.fl4_tos ^ tos)) == 0 &&
2133 rth->fl.mark == skb->mark &&
2134 net_eq(dev_net(rth->u.dst.dev), net) &&
2135 !rt_is_expired(rth)) {
2136 dst_use(&rth->u.dst, jiffies);
2137 RT_CACHE_STAT_INC(in_hit);
2138 rcu_read_unlock();
2139 skb->rtable = rth;
2140 return 0;
2141 }
2142 RT_CACHE_STAT_INC(in_hlist_search);
2143 }
2144 rcu_read_unlock();
2145
2146 /* Multicast recognition logic is moved from route cache to here.
2147 The problem was that too many Ethernet cards have broken/missing
2148 hardware multicast filters :-( As result the host on multicasting
2149 network acquires a lot of useless route cache entries, sort of
2150 SDR messages from all the world. Now we try to get rid of them.
2151 Really, provided software IP multicast filter is organized
2152 reasonably (at least, hashed), it does not result in a slowdown
2153 comparing with route cache reject entries.
2154 Note, that multicast routers are not affected, because
2155 route cache entry is created eventually.
2156 */
2157 if (ipv4_is_multicast(daddr)) {
2158 struct in_device *in_dev;
2159
2160 rcu_read_lock();
2161 if ((in_dev = __in_dev_get_rcu(dev)) != NULL) {
2162 int our = ip_check_mc(in_dev, daddr, saddr,
2163 ip_hdr(skb)->protocol);
2164 if (our
2165 #ifdef CONFIG_IP_MROUTE
2166 || (!ipv4_is_local_multicast(daddr) &&
2167 IN_DEV_MFORWARD(in_dev))
2168 #endif
2169 ) {
2170 rcu_read_unlock();
2171 return ip_route_input_mc(skb, daddr, saddr,
2172 tos, dev, our);
2173 }
2174 }
2175 rcu_read_unlock();
2176 return -EINVAL;
2177 }
2178 return ip_route_input_slow(skb, daddr, saddr, tos, dev);
2179 }
2180
2181 static int __mkroute_output(struct rtable **result,
2182 struct fib_result *res,
2183 const struct flowi *fl,
2184 const struct flowi *oldflp,
2185 struct net_device *dev_out,
2186 unsigned flags)
2187 {
2188 struct rtable *rth;
2189 struct in_device *in_dev;
2190 u32 tos = RT_FL_TOS(oldflp);
2191 int err = 0;
2192
2193 if (ipv4_is_loopback(fl->fl4_src) && !(dev_out->flags&IFF_LOOPBACK))
2194 return -EINVAL;
2195
2196 if (fl->fl4_dst == htonl(0xFFFFFFFF))
2197 res->type = RTN_BROADCAST;
2198 else if (ipv4_is_multicast(fl->fl4_dst))
2199 res->type = RTN_MULTICAST;
2200 else if (ipv4_is_lbcast(fl->fl4_dst) || ipv4_is_zeronet(fl->fl4_dst))
2201 return -EINVAL;
2202
2203 if (dev_out->flags & IFF_LOOPBACK)
2204 flags |= RTCF_LOCAL;
2205
2206 /* get work reference to inet device */
2207 in_dev = in_dev_get(dev_out);
2208 if (!in_dev)
2209 return -EINVAL;
2210
2211 if (res->type == RTN_BROADCAST) {
2212 flags |= RTCF_BROADCAST | RTCF_LOCAL;
2213 if (res->fi) {
2214 fib_info_put(res->fi);
2215 res->fi = NULL;
2216 }
2217 } else if (res->type == RTN_MULTICAST) {
2218 flags |= RTCF_MULTICAST|RTCF_LOCAL;
2219 if (!ip_check_mc(in_dev, oldflp->fl4_dst, oldflp->fl4_src,
2220 oldflp->proto))
2221 flags &= ~RTCF_LOCAL;
2222 /* If multicast route do not exist use
2223 default one, but do not gateway in this case.
2224 Yes, it is hack.
2225 */
2226 if (res->fi && res->prefixlen < 4) {
2227 fib_info_put(res->fi);
2228 res->fi = NULL;
2229 }
2230 }
2231
2232
2233 rth = dst_alloc(&ipv4_dst_ops);
2234 if (!rth) {
2235 err = -ENOBUFS;
2236 goto cleanup;
2237 }
2238
2239 atomic_set(&rth->u.dst.__refcnt, 1);
2240 rth->u.dst.flags= DST_HOST;
2241 if (IN_DEV_CONF_GET(in_dev, NOXFRM))
2242 rth->u.dst.flags |= DST_NOXFRM;
2243 if (IN_DEV_CONF_GET(in_dev, NOPOLICY))
2244 rth->u.dst.flags |= DST_NOPOLICY;
2245
2246 rth->fl.fl4_dst = oldflp->fl4_dst;
2247 rth->fl.fl4_tos = tos;
2248 rth->fl.fl4_src = oldflp->fl4_src;
2249 rth->fl.oif = oldflp->oif;
2250 rth->fl.mark = oldflp->mark;
2251 rth->rt_dst = fl->fl4_dst;
2252 rth->rt_src = fl->fl4_src;
2253 rth->rt_iif = oldflp->oif ? : dev_out->ifindex;
2254 /* get references to the devices that are to be hold by the routing
2255 cache entry */
2256 rth->u.dst.dev = dev_out;
2257 dev_hold(dev_out);
2258 rth->idev = in_dev_get(dev_out);
2259 rth->rt_gateway = fl->fl4_dst;
2260 rth->rt_spec_dst= fl->fl4_src;
2261
2262 rth->u.dst.output=ip_output;
2263 rth->rt_genid = rt_genid(dev_net(dev_out));
2264
2265 RT_CACHE_STAT_INC(out_slow_tot);
2266
2267 if (flags & RTCF_LOCAL) {
2268 rth->u.dst.input = ip_local_deliver;
2269 rth->rt_spec_dst = fl->fl4_dst;
2270 }
2271 if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) {
2272 rth->rt_spec_dst = fl->fl4_src;
2273 if (flags & RTCF_LOCAL &&
2274 !(dev_out->flags & IFF_LOOPBACK)) {
2275 rth->u.dst.output = ip_mc_output;
2276 RT_CACHE_STAT_INC(out_slow_mc);
2277 }
2278 #ifdef CONFIG_IP_MROUTE
2279 if (res->type == RTN_MULTICAST) {
2280 if (IN_DEV_MFORWARD(in_dev) &&
2281 !ipv4_is_local_multicast(oldflp->fl4_dst)) {
2282 rth->u.dst.input = ip_mr_input;
2283 rth->u.dst.output = ip_mc_output;
2284 }
2285 }
2286 #endif
2287 }
2288
2289 rt_set_nexthop(rth, res, 0);
2290
2291 rth->rt_flags = flags;
2292
2293 *result = rth;
2294 cleanup:
2295 /* release work reference to inet device */
2296 in_dev_put(in_dev);
2297
2298 return err;
2299 }
2300
2301 static int ip_mkroute_output(struct rtable **rp,
2302 struct fib_result *res,
2303 const struct flowi *fl,
2304 const struct flowi *oldflp,
2305 struct net_device *dev_out,
2306 unsigned flags)
2307 {
2308 struct rtable *rth = NULL;
2309 int err = __mkroute_output(&rth, res, fl, oldflp, dev_out, flags);
2310 unsigned hash;
2311 if (err == 0) {
2312 hash = rt_hash(oldflp->fl4_dst, oldflp->fl4_src, oldflp->oif,
2313 rt_genid(dev_net(dev_out)));
2314 err = rt_intern_hash(hash, rth, rp);
2315 }
2316
2317 return err;
2318 }
2319
2320 /*
2321 * Major route resolver routine.
2322 */
2323
2324 static int ip_route_output_slow(struct net *net, struct rtable **rp,
2325 const struct flowi *oldflp)
2326 {
2327 u32 tos = RT_FL_TOS(oldflp);
2328 struct flowi fl = { .nl_u = { .ip4_u =
2329 { .daddr = oldflp->fl4_dst,
2330 .saddr = oldflp->fl4_src,
2331 .tos = tos & IPTOS_RT_MASK,
2332 .scope = ((tos & RTO_ONLINK) ?
2333 RT_SCOPE_LINK :
2334 RT_SCOPE_UNIVERSE),
2335 } },
2336 .mark = oldflp->mark,
2337 .iif = net->loopback_dev->ifindex,
2338 .oif = oldflp->oif };
2339 struct fib_result res;
2340 unsigned flags = 0;
2341 struct net_device *dev_out = NULL;
2342 int free_res = 0;
2343 int err;
2344
2345
2346 res.fi = NULL;
2347 #ifdef CONFIG_IP_MULTIPLE_TABLES
2348 res.r = NULL;
2349 #endif
2350
2351 if (oldflp->fl4_src) {
2352 err = -EINVAL;
2353 if (ipv4_is_multicast(oldflp->fl4_src) ||
2354 ipv4_is_lbcast(oldflp->fl4_src) ||
2355 ipv4_is_zeronet(oldflp->fl4_src))
2356 goto out;
2357
2358 /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
2359 dev_out = ip_dev_find(net, oldflp->fl4_src);
2360 if (dev_out == NULL)
2361 goto out;
2362
2363 /* I removed check for oif == dev_out->oif here.
2364 It was wrong for two reasons:
2365 1. ip_dev_find(net, saddr) can return wrong iface, if saddr
2366 is assigned to multiple interfaces.
2367 2. Moreover, we are allowed to send packets with saddr
2368 of another iface. --ANK
2369 */
2370
2371 if (oldflp->oif == 0
2372 && (ipv4_is_multicast(oldflp->fl4_dst) ||
2373 oldflp->fl4_dst == htonl(0xFFFFFFFF))) {
2374 /* Special hack: user can direct multicasts
2375 and limited broadcast via necessary interface
2376 without fiddling with IP_MULTICAST_IF or IP_PKTINFO.
2377 This hack is not just for fun, it allows
2378 vic,vat and friends to work.
2379 They bind socket to loopback, set ttl to zero
2380 and expect that it will work.
2381 From the viewpoint of routing cache they are broken,
2382 because we are not allowed to build multicast path
2383 with loopback source addr (look, routing cache
2384 cannot know, that ttl is zero, so that packet
2385 will not leave this host and route is valid).
2386 Luckily, this hack is good workaround.
2387 */
2388
2389 fl.oif = dev_out->ifindex;
2390 goto make_route;
2391 }
2392 if (dev_out)
2393 dev_put(dev_out);
2394 dev_out = NULL;
2395 }
2396
2397
2398 if (oldflp->oif) {
2399 dev_out = dev_get_by_index(net, oldflp->oif);
2400 err = -ENODEV;
2401 if (dev_out == NULL)
2402 goto out;
2403
2404 /* RACE: Check return value of inet_select_addr instead. */
2405 if (__in_dev_get_rtnl(dev_out) == NULL) {
2406 dev_put(dev_out);
2407 goto out; /* Wrong error code */
2408 }
2409
2410 if (ipv4_is_local_multicast(oldflp->fl4_dst) ||
2411 oldflp->fl4_dst == htonl(0xFFFFFFFF)) {
2412 if (!fl.fl4_src)
2413 fl.fl4_src = inet_select_addr(dev_out, 0,
2414 RT_SCOPE_LINK);
2415 goto make_route;
2416 }
2417 if (!fl.fl4_src) {
2418 if (ipv4_is_multicast(oldflp->fl4_dst))
2419 fl.fl4_src = inet_select_addr(dev_out, 0,
2420 fl.fl4_scope);
2421 else if (!oldflp->fl4_dst)
2422 fl.fl4_src = inet_select_addr(dev_out, 0,
2423 RT_SCOPE_HOST);
2424 }
2425 }
2426
2427 if (!fl.fl4_dst) {
2428 fl.fl4_dst = fl.fl4_src;
2429 if (!fl.fl4_dst)
2430 fl.fl4_dst = fl.fl4_src = htonl(INADDR_LOOPBACK);
2431 if (dev_out)
2432 dev_put(dev_out);
2433 dev_out = net->loopback_dev;
2434 dev_hold(dev_out);
2435 fl.oif = net->loopback_dev->ifindex;
2436 res.type = RTN_LOCAL;
2437 flags |= RTCF_LOCAL;
2438 goto make_route;
2439 }
2440
2441 if (fib_lookup(net, &fl, &res)) {
2442 res.fi = NULL;
2443 if (oldflp->oif) {
2444 /* Apparently, routing tables are wrong. Assume,
2445 that the destination is on link.
2446
2447 WHY? DW.
2448 Because we are allowed to send to iface
2449 even if it has NO routes and NO assigned
2450 addresses. When oif is specified, routing
2451 tables are looked up with only one purpose:
2452 to catch if destination is gatewayed, rather than
2453 direct. Moreover, if MSG_DONTROUTE is set,
2454 we send packet, ignoring both routing tables
2455 and ifaddr state. --ANK
2456
2457
2458 We could make it even if oif is unknown,
2459 likely IPv6, but we do not.
2460 */
2461
2462 if (fl.fl4_src == 0)
2463 fl.fl4_src = inet_select_addr(dev_out, 0,
2464 RT_SCOPE_LINK);
2465 res.type = RTN_UNICAST;
2466 goto make_route;
2467 }
2468 if (dev_out)
2469 dev_put(dev_out);
2470 err = -ENETUNREACH;
2471 goto out;
2472 }
2473 free_res = 1;
2474
2475 if (res.type == RTN_LOCAL) {
2476 if (!fl.fl4_src)
2477 fl.fl4_src = fl.fl4_dst;
2478 if (dev_out)
2479 dev_put(dev_out);
2480 dev_out = net->loopback_dev;
2481 dev_hold(dev_out);
2482 fl.oif = dev_out->ifindex;
2483 if (res.fi)
2484 fib_info_put(res.fi);
2485 res.fi = NULL;
2486 flags |= RTCF_LOCAL;
2487 goto make_route;
2488 }
2489
2490 #ifdef CONFIG_IP_ROUTE_MULTIPATH
2491 if (res.fi->fib_nhs > 1 && fl.oif == 0)
2492 fib_select_multipath(&fl, &res);
2493 else
2494 #endif
2495 if (!res.prefixlen && res.type == RTN_UNICAST && !fl.oif)
2496 fib_select_default(net, &fl, &res);
2497
2498 if (!fl.fl4_src)
2499 fl.fl4_src = FIB_RES_PREFSRC(res);
2500
2501 if (dev_out)
2502 dev_put(dev_out);
2503 dev_out = FIB_RES_DEV(res);
2504 dev_hold(dev_out);
2505 fl.oif = dev_out->ifindex;
2506
2507
2508 make_route:
2509 err = ip_mkroute_output(rp, &res, &fl, oldflp, dev_out, flags);
2510
2511
2512 if (free_res)
2513 fib_res_put(&res);
2514 if (dev_out)
2515 dev_put(dev_out);
2516 out: return err;
2517 }
2518
2519 int __ip_route_output_key(struct net *net, struct rtable **rp,
2520 const struct flowi *flp)
2521 {
2522 unsigned hash;
2523 struct rtable *rth;
2524
2525 hash = rt_hash(flp->fl4_dst, flp->fl4_src, flp->oif, rt_genid(net));
2526
2527 rcu_read_lock_bh();
2528 for (rth = rcu_dereference(rt_hash_table[hash].chain); rth;
2529 rth = rcu_dereference(rth->u.dst.rt_next)) {
2530 if (rth->fl.fl4_dst == flp->fl4_dst &&
2531 rth->fl.fl4_src == flp->fl4_src &&
2532 rth->fl.iif == 0 &&
2533 rth->fl.oif == flp->oif &&
2534 rth->fl.mark == flp->mark &&
2535 !((rth->fl.fl4_tos ^ flp->fl4_tos) &
2536 (IPTOS_RT_MASK | RTO_ONLINK)) &&
2537 net_eq(dev_net(rth->u.dst.dev), net) &&
2538 !rt_is_expired(rth)) {
2539 dst_use(&rth->u.dst, jiffies);
2540 RT_CACHE_STAT_INC(out_hit);
2541 rcu_read_unlock_bh();
2542 *rp = rth;
2543 return 0;
2544 }
2545 RT_CACHE_STAT_INC(out_hlist_search);
2546 }
2547 rcu_read_unlock_bh();
2548
2549 return ip_route_output_slow(net, rp, flp);
2550 }
2551
2552 EXPORT_SYMBOL_GPL(__ip_route_output_key);
2553
2554 static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
2555 {
2556 }
2557
2558 static struct dst_ops ipv4_dst_blackhole_ops = {
2559 .family = AF_INET,
2560 .protocol = __constant_htons(ETH_P_IP),
2561 .destroy = ipv4_dst_destroy,
2562 .check = ipv4_dst_check,
2563 .update_pmtu = ipv4_rt_blackhole_update_pmtu,
2564 .entry_size = sizeof(struct rtable),
2565 .entries = ATOMIC_INIT(0),
2566 };
2567
2568
2569 static int ipv4_dst_blackhole(struct net *net, struct rtable **rp, struct flowi *flp)
2570 {
2571 struct rtable *ort = *rp;
2572 struct rtable *rt = (struct rtable *)
2573 dst_alloc(&ipv4_dst_blackhole_ops);
2574
2575 if (rt) {
2576 struct dst_entry *new = &rt->u.dst;
2577
2578 atomic_set(&new->__refcnt, 1);
2579 new->__use = 1;
2580 new->input = dst_discard;
2581 new->output = dst_discard;
2582 memcpy(new->metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32));
2583
2584 new->dev = ort->u.dst.dev;
2585 if (new->dev)
2586 dev_hold(new->dev);
2587
2588 rt->fl = ort->fl;
2589
2590 rt->idev = ort->idev;
2591 if (rt->idev)
2592 in_dev_hold(rt->idev);
2593 rt->rt_genid = rt_genid(net);
2594 rt->rt_flags = ort->rt_flags;
2595 rt->rt_type = ort->rt_type;
2596 rt->rt_dst = ort->rt_dst;
2597 rt->rt_src = ort->rt_src;
2598 rt->rt_iif = ort->rt_iif;
2599 rt->rt_gateway = ort->rt_gateway;
2600 rt->rt_spec_dst = ort->rt_spec_dst;
2601 rt->peer = ort->peer;
2602 if (rt->peer)
2603 atomic_inc(&rt->peer->refcnt);
2604
2605 dst_free(new);
2606 }
2607
2608 dst_release(&(*rp)->u.dst);
2609 *rp = rt;
2610 return (rt ? 0 : -ENOMEM);
2611 }
2612
2613 int ip_route_output_flow(struct net *net, struct rtable **rp, struct flowi *flp,
2614 struct sock *sk, int flags)
2615 {
2616 int err;
2617
2618 if ((err = __ip_route_output_key(net, rp, flp)) != 0)
2619 return err;
2620
2621 if (flp->proto) {
2622 if (!flp->fl4_src)
2623 flp->fl4_src = (*rp)->rt_src;
2624 if (!flp->fl4_dst)
2625 flp->fl4_dst = (*rp)->rt_dst;
2626 err = __xfrm_lookup((struct dst_entry **)rp, flp, sk,
2627 flags ? XFRM_LOOKUP_WAIT : 0);
2628 if (err == -EREMOTE)
2629 err = ipv4_dst_blackhole(net, rp, flp);
2630
2631 return err;
2632 }
2633
2634 return 0;
2635 }
2636
2637 EXPORT_SYMBOL_GPL(ip_route_output_flow);
2638
2639 int ip_route_output_key(struct net *net, struct rtable **rp, struct flowi *flp)
2640 {
2641 return ip_route_output_flow(net, rp, flp, NULL, 0);
2642 }
2643
2644 static int rt_fill_info(struct sk_buff *skb, u32 pid, u32 seq, int event,
2645 int nowait, unsigned int flags)
2646 {
2647 struct rtable *rt = skb->rtable;
2648 struct rtmsg *r;
2649 struct nlmsghdr *nlh;
2650 long expires;
2651 u32 id = 0, ts = 0, tsage = 0, error;
2652
2653 nlh = nlmsg_put(skb, pid, seq, event, sizeof(*r), flags);
2654 if (nlh == NULL)
2655 return -EMSGSIZE;
2656
2657 r = nlmsg_data(nlh);
2658 r->rtm_family = AF_INET;
2659 r->rtm_dst_len = 32;
2660 r->rtm_src_len = 0;
2661 r->rtm_tos = rt->fl.fl4_tos;
2662 r->rtm_table = RT_TABLE_MAIN;
2663 NLA_PUT_U32(skb, RTA_TABLE, RT_TABLE_MAIN);
2664 r->rtm_type = rt->rt_type;
2665 r->rtm_scope = RT_SCOPE_UNIVERSE;
2666 r->rtm_protocol = RTPROT_UNSPEC;
2667 r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
2668 if (rt->rt_flags & RTCF_NOTIFY)
2669 r->rtm_flags |= RTM_F_NOTIFY;
2670
2671 NLA_PUT_BE32(skb, RTA_DST, rt->rt_dst);
2672
2673 if (rt->fl.fl4_src) {
2674 r->rtm_src_len = 32;
2675 NLA_PUT_BE32(skb, RTA_SRC, rt->fl.fl4_src);
2676 }
2677 if (rt->u.dst.dev)
2678 NLA_PUT_U32(skb, RTA_OIF, rt->u.dst.dev->ifindex);
2679 #ifdef CONFIG_NET_CLS_ROUTE
2680 if (rt->u.dst.tclassid)
2681 NLA_PUT_U32(skb, RTA_FLOW, rt->u.dst.tclassid);
2682 #endif
2683 if (rt->fl.iif)
2684 NLA_PUT_BE32(skb, RTA_PREFSRC, rt->rt_spec_dst);
2685 else if (rt->rt_src != rt->fl.fl4_src)
2686 NLA_PUT_BE32(skb, RTA_PREFSRC, rt->rt_src);
2687
2688 if (rt->rt_dst != rt->rt_gateway)
2689 NLA_PUT_BE32(skb, RTA_GATEWAY, rt->rt_gateway);
2690
2691 if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0)
2692 goto nla_put_failure;
2693
2694 error = rt->u.dst.error;
2695 expires = rt->u.dst.expires ? rt->u.dst.expires - jiffies : 0;
2696 if (rt->peer) {
2697 id = rt->peer->ip_id_count;
2698 if (rt->peer->tcp_ts_stamp) {
2699 ts = rt->peer->tcp_ts;
2700 tsage = get_seconds() - rt->peer->tcp_ts_stamp;
2701 }
2702 }
2703
2704 if (rt->fl.iif) {
2705 #ifdef CONFIG_IP_MROUTE
2706 __be32 dst = rt->rt_dst;
2707
2708 if (ipv4_is_multicast(dst) && !ipv4_is_local_multicast(dst) &&
2709 IPV4_DEVCONF_ALL(&init_net, MC_FORWARDING)) {
2710 int err = ipmr_get_route(skb, r, nowait);
2711 if (err <= 0) {
2712 if (!nowait) {
2713 if (err == 0)
2714 return 0;
2715 goto nla_put_failure;
2716 } else {
2717 if (err == -EMSGSIZE)
2718 goto nla_put_failure;
2719 error = err;
2720 }
2721 }
2722 } else
2723 #endif
2724 NLA_PUT_U32(skb, RTA_IIF, rt->fl.iif);
2725 }
2726
2727 if (rtnl_put_cacheinfo(skb, &rt->u.dst, id, ts, tsage,
2728 expires, error) < 0)
2729 goto nla_put_failure;
2730
2731 return nlmsg_end(skb, nlh);
2732
2733 nla_put_failure:
2734 nlmsg_cancel(skb, nlh);
2735 return -EMSGSIZE;
2736 }
2737
2738 static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
2739 {
2740 struct net *net = sock_net(in_skb->sk);
2741 struct rtmsg *rtm;
2742 struct nlattr *tb[RTA_MAX+1];
2743 struct rtable *rt = NULL;
2744 __be32 dst = 0;
2745 __be32 src = 0;
2746 u32 iif;
2747 int err;
2748 struct sk_buff *skb;
2749
2750 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy);
2751 if (err < 0)
2752 goto errout;
2753
2754 rtm = nlmsg_data(nlh);
2755
2756 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2757 if (skb == NULL) {
2758 err = -ENOBUFS;
2759 goto errout;
2760 }
2761
2762 /* Reserve room for dummy headers, this skb can pass
2763 through good chunk of routing engine.
2764 */
2765 skb_reset_mac_header(skb);
2766 skb_reset_network_header(skb);
2767
2768 /* Bugfix: need to give ip_route_input enough of an IP header to not gag. */
2769 ip_hdr(skb)->protocol = IPPROTO_ICMP;
2770 skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr));
2771
2772 src = tb[RTA_SRC] ? nla_get_be32(tb[RTA_SRC]) : 0;
2773 dst = tb[RTA_DST] ? nla_get_be32(tb[RTA_DST]) : 0;
2774 iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0;
2775
2776 if (iif) {
2777 struct net_device *dev;
2778
2779 dev = __dev_get_by_index(net, iif);
2780 if (dev == NULL) {
2781 err = -ENODEV;
2782 goto errout_free;
2783 }
2784
2785 skb->protocol = htons(ETH_P_IP);
2786 skb->dev = dev;
2787 local_bh_disable();
2788 err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev);
2789 local_bh_enable();
2790
2791 rt = skb->rtable;
2792 if (err == 0 && rt->u.dst.error)
2793 err = -rt->u.dst.error;
2794 } else {
2795 struct flowi fl = {
2796 .nl_u = {
2797 .ip4_u = {
2798 .daddr = dst,
2799 .saddr = src,
2800 .tos = rtm->rtm_tos,
2801 },
2802 },
2803 .oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0,
2804 };
2805 err = ip_route_output_key(net, &rt, &fl);
2806 }
2807
2808 if (err)
2809 goto errout_free;
2810
2811 skb->rtable = rt;
2812 if (rtm->rtm_flags & RTM_F_NOTIFY)
2813 rt->rt_flags |= RTCF_NOTIFY;
2814
2815 err = rt_fill_info(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq,
2816 RTM_NEWROUTE, 0, 0);
2817 if (err <= 0)
2818 goto errout_free;
2819
2820 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
2821 errout:
2822 return err;
2823
2824 errout_free:
2825 kfree_skb(skb);
2826 goto errout;
2827 }
2828
2829 int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb)
2830 {
2831 struct rtable *rt;
2832 int h, s_h;
2833 int idx, s_idx;
2834 struct net *net;
2835
2836 net = sock_net(skb->sk);
2837
2838 s_h = cb->args[0];
2839 if (s_h < 0)
2840 s_h = 0;
2841 s_idx = idx = cb->args[1];
2842 for (h = s_h; h <= rt_hash_mask; h++) {
2843 rcu_read_lock_bh();
2844 for (rt = rcu_dereference(rt_hash_table[h].chain), idx = 0; rt;
2845 rt = rcu_dereference(rt->u.dst.rt_next), idx++) {
2846 if (!net_eq(dev_net(rt->u.dst.dev), net) || idx < s_idx)
2847 continue;
2848 if (rt_is_expired(rt))
2849 continue;
2850 skb->dst = dst_clone(&rt->u.dst);
2851 if (rt_fill_info(skb, NETLINK_CB(cb->skb).pid,
2852 cb->nlh->nlmsg_seq, RTM_NEWROUTE,
2853 1, NLM_F_MULTI) <= 0) {
2854 dst_release(xchg(&skb->dst, NULL));
2855 rcu_read_unlock_bh();
2856 goto done;
2857 }
2858 dst_release(xchg(&skb->dst, NULL));
2859 }
2860 rcu_read_unlock_bh();
2861 s_idx = 0;
2862 }
2863
2864 done:
2865 cb->args[0] = h;
2866 cb->args[1] = idx;
2867 return skb->len;
2868 }
2869
2870 void ip_rt_multicast_event(struct in_device *in_dev)
2871 {
2872 rt_cache_flush(dev_net(in_dev->dev), 0);
2873 }
2874
2875 #ifdef CONFIG_SYSCTL
2876 static int ipv4_sysctl_rtcache_flush(ctl_table *__ctl, int write,
2877 struct file *filp, void __user *buffer,
2878 size_t *lenp, loff_t *ppos)
2879 {
2880 if (write) {
2881 int flush_delay;
2882 ctl_table ctl;
2883 struct net *net;
2884
2885 memcpy(&ctl, __ctl, sizeof(ctl));
2886 ctl.data = &flush_delay;
2887 proc_dointvec(&ctl, write, filp, buffer, lenp, ppos);
2888
2889 net = (struct net *)__ctl->extra1;
2890 rt_cache_flush(net, flush_delay);
2891 return 0;
2892 }
2893
2894 return -EINVAL;
2895 }
2896
2897 static int ipv4_sysctl_rtcache_flush_strategy(ctl_table *table,
2898 int __user *name,
2899 int nlen,
2900 void __user *oldval,
2901 size_t __user *oldlenp,
2902 void __user *newval,
2903 size_t newlen)
2904 {
2905 int delay;
2906 struct net *net;
2907 if (newlen != sizeof(int))
2908 return -EINVAL;
2909 if (get_user(delay, (int __user *)newval))
2910 return -EFAULT;
2911 net = (struct net *)table->extra1;
2912 rt_cache_flush(net, delay);
2913 return 0;
2914 }
2915
2916 ctl_table ipv4_route_table[] = {
2917 {
2918 .ctl_name = NET_IPV4_ROUTE_GC_THRESH,
2919 .procname = "gc_thresh",
2920 .data = &ipv4_dst_ops.gc_thresh,
2921 .maxlen = sizeof(int),
2922 .mode = 0644,
2923 .proc_handler = &proc_dointvec,
2924 },
2925 {
2926 .ctl_name = NET_IPV4_ROUTE_MAX_SIZE,
2927 .procname = "max_size",
2928 .data = &ip_rt_max_size,
2929 .maxlen = sizeof(int),
2930 .mode = 0644,
2931 .proc_handler = &proc_dointvec,
2932 },
2933 {
2934 /* Deprecated. Use gc_min_interval_ms */
2935
2936 .ctl_name = NET_IPV4_ROUTE_GC_MIN_INTERVAL,
2937 .procname = "gc_min_interval",
2938 .data = &ip_rt_gc_min_interval,
2939 .maxlen = sizeof(int),
2940 .mode = 0644,
2941 .proc_handler = &proc_dointvec_jiffies,
2942 .strategy = &sysctl_jiffies,
2943 },
2944 {
2945 .ctl_name = NET_IPV4_ROUTE_GC_MIN_INTERVAL_MS,
2946 .procname = "gc_min_interval_ms",
2947 .data = &ip_rt_gc_min_interval,
2948 .maxlen = sizeof(int),
2949 .mode = 0644,
2950 .proc_handler = &proc_dointvec_ms_jiffies,
2951 .strategy = &sysctl_ms_jiffies,
2952 },
2953 {
2954 .ctl_name = NET_IPV4_ROUTE_GC_TIMEOUT,
2955 .procname = "gc_timeout",
2956 .data = &ip_rt_gc_timeout,
2957 .maxlen = sizeof(int),
2958 .mode = 0644,
2959 .proc_handler = &proc_dointvec_jiffies,
2960 .strategy = &sysctl_jiffies,
2961 },
2962 {
2963 .ctl_name = NET_IPV4_ROUTE_GC_INTERVAL,
2964 .procname = "gc_interval",
2965 .data = &ip_rt_gc_interval,
2966 .maxlen = sizeof(int),
2967 .mode = 0644,
2968 .proc_handler = &proc_dointvec_jiffies,
2969 .strategy = &sysctl_jiffies,
2970 },
2971 {
2972 .ctl_name = NET_IPV4_ROUTE_REDIRECT_LOAD,
2973 .procname = "redirect_load",
2974 .data = &ip_rt_redirect_load,
2975 .maxlen = sizeof(int),
2976 .mode = 0644,
2977 .proc_handler = &proc_dointvec,
2978 },
2979 {
2980 .ctl_name = NET_IPV4_ROUTE_REDIRECT_NUMBER,
2981 .procname = "redirect_number",
2982 .data = &ip_rt_redirect_number,
2983 .maxlen = sizeof(int),
2984 .mode = 0644,
2985 .proc_handler = &proc_dointvec,
2986 },
2987 {
2988 .ctl_name = NET_IPV4_ROUTE_REDIRECT_SILENCE,
2989 .procname = "redirect_silence",
2990 .data = &ip_rt_redirect_silence,
2991 .maxlen = sizeof(int),
2992 .mode = 0644,
2993 .proc_handler = &proc_dointvec,
2994 },
2995 {
2996 .ctl_name = NET_IPV4_ROUTE_ERROR_COST,
2997 .procname = "error_cost",
2998 .data = &ip_rt_error_cost,
2999 .maxlen = sizeof(int),
3000 .mode = 0644,
3001 .proc_handler = &proc_dointvec,
3002 },
3003 {
3004 .ctl_name = NET_IPV4_ROUTE_ERROR_BURST,
3005 .procname = "error_burst",
3006 .data = &ip_rt_error_burst,
3007 .maxlen = sizeof(int),
3008 .mode = 0644,
3009 .proc_handler = &proc_dointvec,
3010 },
3011 {
3012 .ctl_name = NET_IPV4_ROUTE_GC_ELASTICITY,
3013 .procname = "gc_elasticity",
3014 .data = &ip_rt_gc_elasticity,
3015 .maxlen = sizeof(int),
3016 .mode = 0644,
3017 .proc_handler = &proc_dointvec,
3018 },
3019 {
3020 .ctl_name = NET_IPV4_ROUTE_MTU_EXPIRES,
3021 .procname = "mtu_expires",
3022 .data = &ip_rt_mtu_expires,
3023 .maxlen = sizeof(int),
3024 .mode = 0644,
3025 .proc_handler = &proc_dointvec_jiffies,
3026 .strategy = &sysctl_jiffies,
3027 },
3028 {
3029 .ctl_name = NET_IPV4_ROUTE_MIN_PMTU,
3030 .procname = "min_pmtu",
3031 .data = &ip_rt_min_pmtu,
3032 .maxlen = sizeof(int),
3033 .mode = 0644,
3034 .proc_handler = &proc_dointvec,
3035 },
3036 {
3037 .ctl_name = NET_IPV4_ROUTE_MIN_ADVMSS,
3038 .procname = "min_adv_mss",
3039 .data = &ip_rt_min_advmss,
3040 .maxlen = sizeof(int),
3041 .mode = 0644,
3042 .proc_handler = &proc_dointvec,
3043 },
3044 {
3045 .ctl_name = NET_IPV4_ROUTE_SECRET_INTERVAL,
3046 .procname = "secret_interval",
3047 .data = &ip_rt_secret_interval,
3048 .maxlen = sizeof(int),
3049 .mode = 0644,
3050 .proc_handler = &proc_dointvec_jiffies,
3051 .strategy = &sysctl_jiffies,
3052 },
3053 { .ctl_name = 0 }
3054 };
3055
3056 static __net_initdata struct ctl_path ipv4_route_path[] = {
3057 { .procname = "net", .ctl_name = CTL_NET, },
3058 { .procname = "ipv4", .ctl_name = NET_IPV4, },
3059 { .procname = "route", .ctl_name = NET_IPV4_ROUTE, },
3060 { },
3061 };
3062
3063
3064 static struct ctl_table ipv4_route_flush_table[] = {
3065 {
3066 .ctl_name = NET_IPV4_ROUTE_FLUSH,
3067 .procname = "flush",
3068 .maxlen = sizeof(int),
3069 .mode = 0200,
3070 .proc_handler = &ipv4_sysctl_rtcache_flush,
3071 .strategy = &ipv4_sysctl_rtcache_flush_strategy,
3072 },
3073 { .ctl_name = 0 },
3074 };
3075
3076 static __net_init int sysctl_route_net_init(struct net *net)
3077 {
3078 struct ctl_table *tbl;
3079
3080 tbl = ipv4_route_flush_table;
3081 if (net != &init_net) {
3082 tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL);
3083 if (tbl == NULL)
3084 goto err_dup;
3085 }
3086 tbl[0].extra1 = net;
3087
3088 net->ipv4.route_hdr =
3089 register_net_sysctl_table(net, ipv4_route_path, tbl);
3090 if (net->ipv4.route_hdr == NULL)
3091 goto err_reg;
3092 return 0;
3093
3094 err_reg:
3095 if (tbl != ipv4_route_flush_table)
3096 kfree(tbl);
3097 err_dup:
3098 return -ENOMEM;
3099 }
3100
3101 static __net_exit void sysctl_route_net_exit(struct net *net)
3102 {
3103 struct ctl_table *tbl;
3104
3105 tbl = net->ipv4.route_hdr->ctl_table_arg;
3106 unregister_net_sysctl_table(net->ipv4.route_hdr);
3107 BUG_ON(tbl == ipv4_route_flush_table);
3108 kfree(tbl);
3109 }
3110
3111 static __net_initdata struct pernet_operations sysctl_route_ops = {
3112 .init = sysctl_route_net_init,
3113 .exit = sysctl_route_net_exit,
3114 };
3115 #endif
3116
3117
3118 static __net_init int rt_secret_timer_init(struct net *net)
3119 {
3120 atomic_set(&net->ipv4.rt_genid,
3121 (int) ((num_physpages ^ (num_physpages>>8)) ^
3122 (jiffies ^ (jiffies >> 7))));
3123
3124 net->ipv4.rt_secret_timer.function = rt_secret_rebuild;
3125 net->ipv4.rt_secret_timer.data = (unsigned long)net;
3126 init_timer_deferrable(&net->ipv4.rt_secret_timer);
3127
3128 net->ipv4.rt_secret_timer.expires =
3129 jiffies + net_random() % ip_rt_secret_interval +
3130 ip_rt_secret_interval;
3131 add_timer(&net->ipv4.rt_secret_timer);
3132 return 0;
3133 }
3134
3135 static __net_exit void rt_secret_timer_exit(struct net *net)
3136 {
3137 del_timer_sync(&net->ipv4.rt_secret_timer);
3138 }
3139
3140 static __net_initdata struct pernet_operations rt_secret_timer_ops = {
3141 .init = rt_secret_timer_init,
3142 .exit = rt_secret_timer_exit,
3143 };
3144
3145
3146 #ifdef CONFIG_NET_CLS_ROUTE
3147 struct ip_rt_acct *ip_rt_acct __read_mostly;
3148 #endif /* CONFIG_NET_CLS_ROUTE */
3149
3150 static __initdata unsigned long rhash_entries;
3151 static int __init set_rhash_entries(char *str)
3152 {
3153 if (!str)
3154 return 0;
3155 rhash_entries = simple_strtoul(str, &str, 0);
3156 return 1;
3157 }
3158 __setup("rhash_entries=", set_rhash_entries);
3159
3160 int __init ip_rt_init(void)
3161 {
3162 int rc = 0;
3163
3164 #ifdef CONFIG_NET_CLS_ROUTE
3165 ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct));
3166 if (!ip_rt_acct)
3167 panic("IP: failed to allocate ip_rt_acct\n");
3168 #endif
3169
3170 ipv4_dst_ops.kmem_cachep =
3171 kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0,
3172 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
3173
3174 ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep;
3175
3176 rt_hash_table = (struct rt_hash_bucket *)
3177 alloc_large_system_hash("IP route cache",
3178 sizeof(struct rt_hash_bucket),
3179 rhash_entries,
3180 (num_physpages >= 128 * 1024) ?
3181 15 : 17,
3182 0,
3183 &rt_hash_log,
3184 &rt_hash_mask,
3185 0);
3186 memset(rt_hash_table, 0, (rt_hash_mask + 1) * sizeof(struct rt_hash_bucket));
3187 rt_hash_lock_init();
3188
3189 ipv4_dst_ops.gc_thresh = (rt_hash_mask + 1);
3190 ip_rt_max_size = (rt_hash_mask + 1) * 16;
3191
3192 devinet_init();
3193 ip_fib_init();
3194
3195 /* All the timers, started at system startup tend
3196 to synchronize. Perturb it a bit.
3197 */
3198 schedule_delayed_work(&expires_work,
3199 net_random() % ip_rt_gc_interval + ip_rt_gc_interval);
3200
3201 if (register_pernet_subsys(&rt_secret_timer_ops))
3202 printk(KERN_ERR "Unable to setup rt_secret_timer\n");
3203
3204 if (ip_rt_proc_init())
3205 printk(KERN_ERR "Unable to create route proc files\n");
3206 #ifdef CONFIG_XFRM
3207 xfrm_init();
3208 xfrm4_init();
3209 #endif
3210 rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL);
3211
3212 #ifdef CONFIG_SYSCTL
3213 register_pernet_subsys(&sysctl_route_ops);
3214 #endif
3215 return rc;
3216 }
3217
3218 EXPORT_SYMBOL(__ip_select_ident);
3219 EXPORT_SYMBOL(ip_route_input);
3220 EXPORT_SYMBOL(ip_route_output_key);
AMDTP streaming driver for the Linux FireWire stack (Juju)