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e1000: allow VLAN devices to use TSO and CSUM offload
[linux-2.6/mini2440.git] / net / ipv4 / route.c
bloba6d7c584f53b9a4f7493ac3b73b2e4b2602f66bf
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 if (!rt_hash_table[st->bucket].chain)
286 continue;
287 rcu_read_lock_bh();
288 r = rcu_dereference(rt_hash_table[st->bucket].chain);
289 while (r) {
290 if (dev_net(r->u.dst.dev) == seq_file_net(seq) &&
291 r->rt_genid == st->genid)
292 return r;
293 r = rcu_dereference(r->u.dst.rt_next);
294 }
295 rcu_read_unlock_bh();
296 }
297 return r;
298 }
299
300 static struct rtable *__rt_cache_get_next(struct seq_file *seq,
301 struct rtable *r)
302 {
303 struct rt_cache_iter_state *st = seq->private;
304
305 r = r->u.dst.rt_next;
306 while (!r) {
307 rcu_read_unlock_bh();
308 do {
309 if (--st->bucket < 0)
310 return NULL;
311 } while (!rt_hash_table[st->bucket].chain);
312 rcu_read_lock_bh();
313 r = rt_hash_table[st->bucket].chain;
314 }
315 return rcu_dereference(r);
316 }
317
318 static struct rtable *rt_cache_get_next(struct seq_file *seq,
319 struct rtable *r)
320 {
321 struct rt_cache_iter_state *st = seq->private;
322 while ((r = __rt_cache_get_next(seq, r)) != NULL) {
323 if (dev_net(r->u.dst.dev) != seq_file_net(seq))
324 continue;
325 if (r->rt_genid == st->genid)
326 break;
327 }
328 return r;
329 }
330
331 static struct rtable *rt_cache_get_idx(struct seq_file *seq, loff_t pos)
332 {
333 struct rtable *r = rt_cache_get_first(seq);
334
335 if (r)
336 while (pos && (r = rt_cache_get_next(seq, r)))
337 --pos;
338 return pos ? NULL : r;
339 }
340
341 static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
342 {
343 struct rt_cache_iter_state *st = seq->private;
344 if (*pos)
345 return rt_cache_get_idx(seq, *pos - 1);
346 st->genid = rt_genid(seq_file_net(seq));
347 return SEQ_START_TOKEN;
348 }
349
350 static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
351 {
352 struct rtable *r;
353
354 if (v == SEQ_START_TOKEN)
355 r = rt_cache_get_first(seq);
356 else
357 r = rt_cache_get_next(seq, v);
358 ++*pos;
359 return r;
360 }
361
362 static void rt_cache_seq_stop(struct seq_file *seq, void *v)
363 {
364 if (v && v != SEQ_START_TOKEN)
365 rcu_read_unlock_bh();
366 }
367
368 static int rt_cache_seq_show(struct seq_file *seq, void *v)
369 {
370 if (v == SEQ_START_TOKEN)
371 seq_printf(seq, "%-127s\n",
372 "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t"
373 "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t"
374 "HHUptod\tSpecDst");
375 else {
376 struct rtable *r = v;
377 int len;
378
379 seq_printf(seq, "%s\t%08lX\t%08lX\t%8X\t%d\t%u\t%d\t"
380 "%08lX\t%d\t%u\t%u\t%02X\t%d\t%1d\t%08X%n",
381 r->u.dst.dev ? r->u.dst.dev->name : "*",
382 (unsigned long)r->rt_dst, (unsigned long)r->rt_gateway,
383 r->rt_flags, atomic_read(&r->u.dst.__refcnt),
384 r->u.dst.__use, 0, (unsigned long)r->rt_src,
385 (dst_metric(&r->u.dst, RTAX_ADVMSS) ?
386 (int)dst_metric(&r->u.dst, RTAX_ADVMSS) + 40 : 0),
387 dst_metric(&r->u.dst, RTAX_WINDOW),
388 (int)((dst_metric(&r->u.dst, RTAX_RTT) >> 3) +
389 dst_metric(&r->u.dst, RTAX_RTTVAR)),
390 r->fl.fl4_tos,
391 r->u.dst.hh ? atomic_read(&r->u.dst.hh->hh_refcnt) : -1,
392 r->u.dst.hh ? (r->u.dst.hh->hh_output ==
393 dev_queue_xmit) : 0,
394 r->rt_spec_dst, &len);
395
396 seq_printf(seq, "%*s\n", 127 - len, "");
397 }
398 return 0;
399 }
400
401 static const struct seq_operations rt_cache_seq_ops = {
402 .start = rt_cache_seq_start,
403 .next = rt_cache_seq_next,
404 .stop = rt_cache_seq_stop,
405 .show = rt_cache_seq_show,
406 };
407
408 static int rt_cache_seq_open(struct inode *inode, struct file *file)
409 {
410 return seq_open_net(inode, file, &rt_cache_seq_ops,
411 sizeof(struct rt_cache_iter_state));
412 }
413
414 static const struct file_operations rt_cache_seq_fops = {
415 .owner = THIS_MODULE,
416 .open = rt_cache_seq_open,
417 .read = seq_read,
418 .llseek = seq_lseek,
419 .release = seq_release_net,
420 };
421
422
423 static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos)
424 {
425 int cpu;
426
427 if (*pos == 0)
428 return SEQ_START_TOKEN;
429
430 for (cpu = *pos-1; cpu < NR_CPUS; ++cpu) {
431 if (!cpu_possible(cpu))
432 continue;
433 *pos = cpu+1;
434 return &per_cpu(rt_cache_stat, cpu);
435 }
436 return NULL;
437 }
438
439 static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos)
440 {
441 int cpu;
442
443 for (cpu = *pos; cpu < NR_CPUS; ++cpu) {
444 if (!cpu_possible(cpu))
445 continue;
446 *pos = cpu+1;
447 return &per_cpu(rt_cache_stat, cpu);
448 }
449 return NULL;
450
451 }
452
453 static void rt_cpu_seq_stop(struct seq_file *seq, void *v)
454 {
455
456 }
457
458 static int rt_cpu_seq_show(struct seq_file *seq, void *v)
459 {
460 struct rt_cache_stat *st = v;
461
462 if (v == SEQ_START_TOKEN) {
463 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");
464 return 0;
465 }
466
467 seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x "
468 " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n",
469 atomic_read(&ipv4_dst_ops.entries),
470 st->in_hit,
471 st->in_slow_tot,
472 st->in_slow_mc,
473 st->in_no_route,
474 st->in_brd,
475 st->in_martian_dst,
476 st->in_martian_src,
477
478 st->out_hit,
479 st->out_slow_tot,
480 st->out_slow_mc,
481
482 st->gc_total,
483 st->gc_ignored,
484 st->gc_goal_miss,
485 st->gc_dst_overflow,
486 st->in_hlist_search,
487 st->out_hlist_search
488 );
489 return 0;
490 }
491
492 static const struct seq_operations rt_cpu_seq_ops = {
493 .start = rt_cpu_seq_start,
494 .next = rt_cpu_seq_next,
495 .stop = rt_cpu_seq_stop,
496 .show = rt_cpu_seq_show,
497 };
498
499
500 static int rt_cpu_seq_open(struct inode *inode, struct file *file)
501 {
502 return seq_open(file, &rt_cpu_seq_ops);
503 }
504
505 static const struct file_operations rt_cpu_seq_fops = {
506 .owner = THIS_MODULE,
507 .open = rt_cpu_seq_open,
508 .read = seq_read,
509 .llseek = seq_lseek,
510 .release = seq_release,
511 };
512
513 #ifdef CONFIG_NET_CLS_ROUTE
514 static int ip_rt_acct_read(char *buffer, char **start, off_t offset,
515 int length, int *eof, void *data)
516 {
517 unsigned int i;
518
519 if ((offset & 3) || (length & 3))
520 return -EIO;
521
522 if (offset >= sizeof(struct ip_rt_acct) * 256) {
523 *eof = 1;
524 return 0;
525 }
526
527 if (offset + length >= sizeof(struct ip_rt_acct) * 256) {
528 length = sizeof(struct ip_rt_acct) * 256 - offset;
529 *eof = 1;
530 }
531
532 offset /= sizeof(u32);
533
534 if (length > 0) {
535 u32 *dst = (u32 *) buffer;
536
537 *start = buffer;
538 memset(dst, 0, length);
539
540 for_each_possible_cpu(i) {
541 unsigned int j;
542 u32 *src;
543
544 src = ((u32 *) per_cpu_ptr(ip_rt_acct, i)) + offset;
545 for (j = 0; j < length/4; j++)
546 dst[j] += src[j];
547 }
548 }
549 return length;
550 }
551 #endif
552
553 static int __net_init ip_rt_do_proc_init(struct net *net)
554 {
555 struct proc_dir_entry *pde;
556
557 pde = proc_net_fops_create(net, "rt_cache", S_IRUGO,
558 &rt_cache_seq_fops);
559 if (!pde)
560 goto err1;
561
562 pde = proc_create("rt_cache", S_IRUGO,
563 net->proc_net_stat, &rt_cpu_seq_fops);
564 if (!pde)
565 goto err2;
566
567 #ifdef CONFIG_NET_CLS_ROUTE
568 pde = create_proc_read_entry("rt_acct", 0, net->proc_net,
569 ip_rt_acct_read, NULL);
570 if (!pde)
571 goto err3;
572 #endif
573 return 0;
574
575 #ifdef CONFIG_NET_CLS_ROUTE
576 err3:
577 remove_proc_entry("rt_cache", net->proc_net_stat);
578 #endif
579 err2:
580 remove_proc_entry("rt_cache", net->proc_net);
581 err1:
582 return -ENOMEM;
583 }
584
585 static void __net_exit ip_rt_do_proc_exit(struct net *net)
586 {
587 remove_proc_entry("rt_cache", net->proc_net_stat);
588 remove_proc_entry("rt_cache", net->proc_net);
589 remove_proc_entry("rt_acct", net->proc_net);
590 }
591
592 static struct pernet_operations ip_rt_proc_ops __net_initdata = {
593 .init = ip_rt_do_proc_init,
594 .exit = ip_rt_do_proc_exit,
595 };
596
597 static int __init ip_rt_proc_init(void)
598 {
599 return register_pernet_subsys(&ip_rt_proc_ops);
600 }
601
602 #else
603 static inline int ip_rt_proc_init(void)
604 {
605 return 0;
606 }
607 #endif /* CONFIG_PROC_FS */
608
609 static inline void rt_free(struct rtable *rt)
610 {
611 call_rcu_bh(&rt->u.dst.rcu_head, dst_rcu_free);
612 }
613
614 static inline void rt_drop(struct rtable *rt)
615 {
616 ip_rt_put(rt);
617 call_rcu_bh(&rt->u.dst.rcu_head, dst_rcu_free);
618 }
619
620 static inline int rt_fast_clean(struct rtable *rth)
621 {
622 /* Kill broadcast/multicast entries very aggresively, if they
623 collide in hash table with more useful entries */
624 return (rth->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) &&
625 rth->fl.iif && rth->u.dst.rt_next;
626 }
627
628 static inline int rt_valuable(struct rtable *rth)
629 {
630 return (rth->rt_flags & (RTCF_REDIRECTED | RTCF_NOTIFY)) ||
631 rth->u.dst.expires;
632 }
633
634 static int rt_may_expire(struct rtable *rth, unsigned long tmo1, unsigned long tmo2)
635 {
636 unsigned long age;
637 int ret = 0;
638
639 if (atomic_read(&rth->u.dst.__refcnt))
640 goto out;
641
642 ret = 1;
643 if (rth->u.dst.expires &&
644 time_after_eq(jiffies, rth->u.dst.expires))
645 goto out;
646
647 age = jiffies - rth->u.dst.lastuse;
648 ret = 0;
649 if ((age <= tmo1 && !rt_fast_clean(rth)) ||
650 (age <= tmo2 && rt_valuable(rth)))
651 goto out;
652 ret = 1;
653 out: return ret;
654 }
655
656 /* Bits of score are:
657 * 31: very valuable
658 * 30: not quite useless
659 * 29..0: usage counter
660 */
661 static inline u32 rt_score(struct rtable *rt)
662 {
663 u32 score = jiffies - rt->u.dst.lastuse;
664
665 score = ~score & ~(3<<30);
666
667 if (rt_valuable(rt))
668 score |= (1<<31);
669
670 if (!rt->fl.iif ||
671 !(rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST|RTCF_LOCAL)))
672 score |= (1<<30);
673
674 return score;
675 }
676
677 static inline int compare_keys(struct flowi *fl1, struct flowi *fl2)
678 {
679 return ((__force u32)((fl1->nl_u.ip4_u.daddr ^ fl2->nl_u.ip4_u.daddr) |
680 (fl1->nl_u.ip4_u.saddr ^ fl2->nl_u.ip4_u.saddr)) |
681 (fl1->mark ^ fl2->mark) |
682 (*(u16 *)&fl1->nl_u.ip4_u.tos ^
683 *(u16 *)&fl2->nl_u.ip4_u.tos) |
684 (fl1->oif ^ fl2->oif) |
685 (fl1->iif ^ fl2->iif)) == 0;
686 }
687
688 static inline int compare_netns(struct rtable *rt1, struct rtable *rt2)
689 {
690 return dev_net(rt1->u.dst.dev) == dev_net(rt2->u.dst.dev);
691 }
692
693 static inline int rt_is_expired(struct rtable *rth)
694 {
695 return rth->rt_genid != rt_genid(dev_net(rth->u.dst.dev));
696 }
697
698 /*
699 * Perform a full scan of hash table and free all entries.
700 * Can be called by a softirq or a process.
701 * In the later case, we want to be reschedule if necessary
702 */
703 static void rt_do_flush(int process_context)
704 {
705 unsigned int i;
706 struct rtable *rth, *next;
707 struct rtable * tail;
708
709 for (i = 0; i <= rt_hash_mask; i++) {
710 if (process_context && need_resched())
711 cond_resched();
712 rth = rt_hash_table[i].chain;
713 if (!rth)
714 continue;
715
716 spin_lock_bh(rt_hash_lock_addr(i));
717 #ifdef CONFIG_NET_NS
718 {
719 struct rtable ** prev, * p;
720
721 rth = rt_hash_table[i].chain;
722
723 /* defer releasing the head of the list after spin_unlock */
724 for (tail = rth; tail; tail = tail->u.dst.rt_next)
725 if (!rt_is_expired(tail))
726 break;
727 if (rth != tail)
728 rt_hash_table[i].chain = tail;
729
730 /* call rt_free on entries after the tail requiring flush */
731 prev = &rt_hash_table[i].chain;
732 for (p = *prev; p; p = next) {
733 next = p->u.dst.rt_next;
734 if (!rt_is_expired(p)) {
735 prev = &p->u.dst.rt_next;
736 } else {
737 *prev = next;
738 rt_free(p);
739 }
740 }
741 }
742 #else
743 rth = rt_hash_table[i].chain;
744 rt_hash_table[i].chain = NULL;
745 tail = NULL;
746 #endif
747 spin_unlock_bh(rt_hash_lock_addr(i));
748
749 for (; rth != tail; rth = next) {
750 next = rth->u.dst.rt_next;
751 rt_free(rth);
752 }
753 }
754 }
755
756 static void rt_check_expire(void)
757 {
758 static unsigned int rover;
759 unsigned int i = rover, goal;
760 struct rtable *rth, **rthp;
761 u64 mult;
762
763 mult = ((u64)ip_rt_gc_interval) << rt_hash_log;
764 if (ip_rt_gc_timeout > 1)
765 do_div(mult, ip_rt_gc_timeout);
766 goal = (unsigned int)mult;
767 if (goal > rt_hash_mask)
768 goal = rt_hash_mask + 1;
769 for (; goal > 0; goal--) {
770 unsigned long tmo = ip_rt_gc_timeout;
771
772 i = (i + 1) & rt_hash_mask;
773 rthp = &rt_hash_table[i].chain;
774
775 if (need_resched())
776 cond_resched();
777
778 if (*rthp == NULL)
779 continue;
780 spin_lock_bh(rt_hash_lock_addr(i));
781 while ((rth = *rthp) != NULL) {
782 if (rt_is_expired(rth)) {
783 *rthp = rth->u.dst.rt_next;
784 rt_free(rth);
785 continue;
786 }
787 if (rth->u.dst.expires) {
788 /* Entry is expired even if it is in use */
789 if (time_before_eq(jiffies, rth->u.dst.expires)) {
790 tmo >>= 1;
791 rthp = &rth->u.dst.rt_next;
792 continue;
793 }
794 } else if (!rt_may_expire(rth, tmo, ip_rt_gc_timeout)) {
795 tmo >>= 1;
796 rthp = &rth->u.dst.rt_next;
797 continue;
798 }
799
800 /* Cleanup aged off entries. */
801 *rthp = rth->u.dst.rt_next;
802 rt_free(rth);
803 }
804 spin_unlock_bh(rt_hash_lock_addr(i));
805 }
806 rover = i;
807 }
808
809 /*
810 * rt_worker_func() is run in process context.
811 * we call rt_check_expire() to scan part of the hash table
812 */
813 static void rt_worker_func(struct work_struct *work)
814 {
815 rt_check_expire();
816 schedule_delayed_work(&expires_work, ip_rt_gc_interval);
817 }
818
819 /*
820 * Pertubation of rt_genid by a small quantity [1..256]
821 * Using 8 bits of shuffling ensure we can call rt_cache_invalidate()
822 * many times (2^24) without giving recent rt_genid.
823 * Jenkins hash is strong enough that litle changes of rt_genid are OK.
824 */
825 static void rt_cache_invalidate(struct net *net)
826 {
827 unsigned char shuffle;
828
829 get_random_bytes(&shuffle, sizeof(shuffle));
830 atomic_add(shuffle + 1U, &net->ipv4.rt_genid);
831 }
832
833 /*
834 * delay < 0 : invalidate cache (fast : entries will be deleted later)
835 * delay >= 0 : invalidate & flush cache (can be long)
836 */
837 void rt_cache_flush(struct net *net, int delay)
838 {
839 rt_cache_invalidate(net);
840 if (delay >= 0)
841 rt_do_flush(!in_softirq());
842 }
843
844 /*
845 * We change rt_genid and let gc do the cleanup
846 */
847 static void rt_secret_rebuild(unsigned long __net)
848 {
849 struct net *net = (struct net *)__net;
850 rt_cache_invalidate(net);
851 mod_timer(&net->ipv4.rt_secret_timer, jiffies + ip_rt_secret_interval);
852 }
853
854 /*
855 Short description of GC goals.
856
857 We want to build algorithm, which will keep routing cache
858 at some equilibrium point, when number of aged off entries
859 is kept approximately equal to newly generated ones.
860
861 Current expiration strength is variable "expire".
862 We try to adjust it dynamically, so that if networking
863 is idle expires is large enough to keep enough of warm entries,
864 and when load increases it reduces to limit cache size.
865 */
866
867 static int rt_garbage_collect(struct dst_ops *ops)
868 {
869 static unsigned long expire = RT_GC_TIMEOUT;
870 static unsigned long last_gc;
871 static int rover;
872 static int equilibrium;
873 struct rtable *rth, **rthp;
874 unsigned long now = jiffies;
875 int goal;
876
877 /*
878 * Garbage collection is pretty expensive,
879 * do not make it too frequently.
880 */
881
882 RT_CACHE_STAT_INC(gc_total);
883
884 if (now - last_gc < ip_rt_gc_min_interval &&
885 atomic_read(&ipv4_dst_ops.entries) < ip_rt_max_size) {
886 RT_CACHE_STAT_INC(gc_ignored);
887 goto out;
888 }
889
890 /* Calculate number of entries, which we want to expire now. */
891 goal = atomic_read(&ipv4_dst_ops.entries) -
892 (ip_rt_gc_elasticity << rt_hash_log);
893 if (goal <= 0) {
894 if (equilibrium < ipv4_dst_ops.gc_thresh)
895 equilibrium = ipv4_dst_ops.gc_thresh;
896 goal = atomic_read(&ipv4_dst_ops.entries) - equilibrium;
897 if (goal > 0) {
898 equilibrium += min_t(unsigned int, goal >> 1, rt_hash_mask + 1);
899 goal = atomic_read(&ipv4_dst_ops.entries) - equilibrium;
900 }
901 } else {
902 /* We are in dangerous area. Try to reduce cache really
903 * aggressively.
904 */
905 goal = max_t(unsigned int, goal >> 1, rt_hash_mask + 1);
906 equilibrium = atomic_read(&ipv4_dst_ops.entries) - goal;
907 }
908
909 if (now - last_gc >= ip_rt_gc_min_interval)
910 last_gc = now;
911
912 if (goal <= 0) {
913 equilibrium += goal;
914 goto work_done;
915 }
916
917 do {
918 int i, k;
919
920 for (i = rt_hash_mask, k = rover; i >= 0; i--) {
921 unsigned long tmo = expire;
922
923 k = (k + 1) & rt_hash_mask;
924 rthp = &rt_hash_table[k].chain;
925 spin_lock_bh(rt_hash_lock_addr(k));
926 while ((rth = *rthp) != NULL) {
927 if (!rt_is_expired(rth) &&
928 !rt_may_expire(rth, tmo, expire)) {
929 tmo >>= 1;
930 rthp = &rth->u.dst.rt_next;
931 continue;
932 }
933 *rthp = rth->u.dst.rt_next;
934 rt_free(rth);
935 goal--;
936 }
937 spin_unlock_bh(rt_hash_lock_addr(k));
938 if (goal <= 0)
939 break;
940 }
941 rover = k;
942
943 if (goal <= 0)
944 goto work_done;
945
946 /* Goal is not achieved. We stop process if:
947
948 - if expire reduced to zero. Otherwise, expire is halfed.
949 - if table is not full.
950 - if we are called from interrupt.
951 - jiffies check is just fallback/debug loop breaker.
952 We will not spin here for long time in any case.
953 */
954
955 RT_CACHE_STAT_INC(gc_goal_miss);
956
957 if (expire == 0)
958 break;
959
960 expire >>= 1;
961 #if RT_CACHE_DEBUG >= 2
962 printk(KERN_DEBUG "expire>> %u %d %d %d\n", expire,
963 atomic_read(&ipv4_dst_ops.entries), goal, i);
964 #endif
965
966 if (atomic_read(&ipv4_dst_ops.entries) < ip_rt_max_size)
967 goto out;
968 } while (!in_softirq() && time_before_eq(jiffies, now));
969
970 if (atomic_read(&ipv4_dst_ops.entries) < ip_rt_max_size)
971 goto out;
972 if (net_ratelimit())
973 printk(KERN_WARNING "dst cache overflow\n");
974 RT_CACHE_STAT_INC(gc_dst_overflow);
975 return 1;
976
977 work_done:
978 expire += ip_rt_gc_min_interval;
979 if (expire > ip_rt_gc_timeout ||
980 atomic_read(&ipv4_dst_ops.entries) < ipv4_dst_ops.gc_thresh)
981 expire = ip_rt_gc_timeout;
982 #if RT_CACHE_DEBUG >= 2
983 printk(KERN_DEBUG "expire++ %u %d %d %d\n", expire,
984 atomic_read(&ipv4_dst_ops.entries), goal, rover);
985 #endif
986 out: return 0;
987 }
988
989 static int rt_intern_hash(unsigned hash, struct rtable *rt, struct rtable **rp)
990 {
991 struct rtable *rth, **rthp;
992 unsigned long now;
993 struct rtable *cand, **candp;
994 u32 min_score;
995 int chain_length;
996 int attempts = !in_softirq();
997
998 restart:
999 chain_length = 0;
1000 min_score = ~(u32)0;
1001 cand = NULL;
1002 candp = NULL;
1003 now = jiffies;
1004
1005 rthp = &rt_hash_table[hash].chain;
1006
1007 spin_lock_bh(rt_hash_lock_addr(hash));
1008 while ((rth = *rthp) != NULL) {
1009 if (rt_is_expired(rth)) {
1010 *rthp = rth->u.dst.rt_next;
1011 rt_free(rth);
1012 continue;
1013 }
1014 if (compare_keys(&rth->fl, &rt->fl) && compare_netns(rth, rt)) {
1015 /* Put it first */
1016 *rthp = rth->u.dst.rt_next;
1017 /*
1018 * Since lookup is lockfree, the deletion
1019 * must be visible to another weakly ordered CPU before
1020 * the insertion at the start of the hash chain.
1021 */
1022 rcu_assign_pointer(rth->u.dst.rt_next,
1023 rt_hash_table[hash].chain);
1024 /*
1025 * Since lookup is lockfree, the update writes
1026 * must be ordered for consistency on SMP.
1027 */
1028 rcu_assign_pointer(rt_hash_table[hash].chain, rth);
1029
1030 dst_use(&rth->u.dst, now);
1031 spin_unlock_bh(rt_hash_lock_addr(hash));
1032
1033 rt_drop(rt);
1034 *rp = rth;
1035 return 0;
1036 }
1037
1038 if (!atomic_read(&rth->u.dst.__refcnt)) {
1039 u32 score = rt_score(rth);
1040
1041 if (score <= min_score) {
1042 cand = rth;
1043 candp = rthp;
1044 min_score = score;
1045 }
1046 }
1047
1048 chain_length++;
1049
1050 rthp = &rth->u.dst.rt_next;
1051 }
1052
1053 if (cand) {
1054 /* ip_rt_gc_elasticity used to be average length of chain
1055 * length, when exceeded gc becomes really aggressive.
1056 *
1057 * The second limit is less certain. At the moment it allows
1058 * only 2 entries per bucket. We will see.
1059 */
1060 if (chain_length > ip_rt_gc_elasticity) {
1061 *candp = cand->u.dst.rt_next;
1062 rt_free(cand);
1063 }
1064 }
1065
1066 /* Try to bind route to arp only if it is output
1067 route or unicast forwarding path.
1068 */
1069 if (rt->rt_type == RTN_UNICAST || rt->fl.iif == 0) {
1070 int err = arp_bind_neighbour(&rt->u.dst);
1071 if (err) {
1072 spin_unlock_bh(rt_hash_lock_addr(hash));
1073
1074 if (err != -ENOBUFS) {
1075 rt_drop(rt);
1076 return err;
1077 }
1078
1079 /* Neighbour tables are full and nothing
1080 can be released. Try to shrink route cache,
1081 it is most likely it holds some neighbour records.
1082 */
1083 if (attempts-- > 0) {
1084 int saved_elasticity = ip_rt_gc_elasticity;
1085 int saved_int = ip_rt_gc_min_interval;
1086 ip_rt_gc_elasticity = 1;
1087 ip_rt_gc_min_interval = 0;
1088 rt_garbage_collect(&ipv4_dst_ops);
1089 ip_rt_gc_min_interval = saved_int;
1090 ip_rt_gc_elasticity = saved_elasticity;
1091 goto restart;
1092 }
1093
1094 if (net_ratelimit())
1095 printk(KERN_WARNING "Neighbour table overflow.\n");
1096 rt_drop(rt);
1097 return -ENOBUFS;
1098 }
1099 }
1100
1101 rt->u.dst.rt_next = rt_hash_table[hash].chain;
1102 #if RT_CACHE_DEBUG >= 2
1103 if (rt->u.dst.rt_next) {
1104 struct rtable *trt;
1105 printk(KERN_DEBUG "rt_cache @%02x: " NIPQUAD_FMT, hash,
1106 NIPQUAD(rt->rt_dst));
1107 for (trt = rt->u.dst.rt_next; trt; trt = trt->u.dst.rt_next)
1108 printk(" . " NIPQUAD_FMT, NIPQUAD(trt->rt_dst));
1109 printk("\n");
1110 }
1111 #endif
1112 rt_hash_table[hash].chain = rt;
1113 spin_unlock_bh(rt_hash_lock_addr(hash));
1114 *rp = rt;
1115 return 0;
1116 }
1117
1118 void rt_bind_peer(struct rtable *rt, int create)
1119 {
1120 static DEFINE_SPINLOCK(rt_peer_lock);
1121 struct inet_peer *peer;
1122
1123 peer = inet_getpeer(rt->rt_dst, create);
1124
1125 spin_lock_bh(&rt_peer_lock);
1126 if (rt->peer == NULL) {
1127 rt->peer = peer;
1128 peer = NULL;
1129 }
1130 spin_unlock_bh(&rt_peer_lock);
1131 if (peer)
1132 inet_putpeer(peer);
1133 }
1134
1135 /*
1136 * Peer allocation may fail only in serious out-of-memory conditions. However
1137 * we still can generate some output.
1138 * Random ID selection looks a bit dangerous because we have no chances to
1139 * select ID being unique in a reasonable period of time.
1140 * But broken packet identifier may be better than no packet at all.
1141 */
1142 static void ip_select_fb_ident(struct iphdr *iph)
1143 {
1144 static DEFINE_SPINLOCK(ip_fb_id_lock);
1145 static u32 ip_fallback_id;
1146 u32 salt;
1147
1148 spin_lock_bh(&ip_fb_id_lock);
1149 salt = secure_ip_id((__force __be32)ip_fallback_id ^ iph->daddr);
1150 iph->id = htons(salt & 0xFFFF);
1151 ip_fallback_id = salt;
1152 spin_unlock_bh(&ip_fb_id_lock);
1153 }
1154
1155 void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more)
1156 {
1157 struct rtable *rt = (struct rtable *) dst;
1158
1159 if (rt) {
1160 if (rt->peer == NULL)
1161 rt_bind_peer(rt, 1);
1162
1163 /* If peer is attached to destination, it is never detached,
1164 so that we need not to grab a lock to dereference it.
1165 */
1166 if (rt->peer) {
1167 iph->id = htons(inet_getid(rt->peer, more));
1168 return;
1169 }
1170 } else
1171 printk(KERN_DEBUG "rt_bind_peer(0) @%p\n",
1172 __builtin_return_address(0));
1173
1174 ip_select_fb_ident(iph);
1175 }
1176
1177 static void rt_del(unsigned hash, struct rtable *rt)
1178 {
1179 struct rtable **rthp, *aux;
1180
1181 rthp = &rt_hash_table[hash].chain;
1182 spin_lock_bh(rt_hash_lock_addr(hash));
1183 ip_rt_put(rt);
1184 while ((aux = *rthp) != NULL) {
1185 if (aux == rt || rt_is_expired(aux)) {
1186 *rthp = aux->u.dst.rt_next;
1187 rt_free(aux);
1188 continue;
1189 }
1190 rthp = &aux->u.dst.rt_next;
1191 }
1192 spin_unlock_bh(rt_hash_lock_addr(hash));
1193 }
1194
1195 void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw,
1196 __be32 saddr, struct net_device *dev)
1197 {
1198 int i, k;
1199 struct in_device *in_dev = in_dev_get(dev);
1200 struct rtable *rth, **rthp;
1201 __be32 skeys[2] = { saddr, 0 };
1202 int ikeys[2] = { dev->ifindex, 0 };
1203 struct netevent_redirect netevent;
1204 struct net *net;
1205
1206 if (!in_dev)
1207 return;
1208
1209 net = dev_net(dev);
1210 if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev)
1211 || ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw)
1212 || ipv4_is_zeronet(new_gw))
1213 goto reject_redirect;
1214
1215 if (!IN_DEV_SHARED_MEDIA(in_dev)) {
1216 if (!inet_addr_onlink(in_dev, new_gw, old_gw))
1217 goto reject_redirect;
1218 if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev))
1219 goto reject_redirect;
1220 } else {
1221 if (inet_addr_type(net, new_gw) != RTN_UNICAST)
1222 goto reject_redirect;
1223 }
1224
1225 for (i = 0; i < 2; i++) {
1226 for (k = 0; k < 2; k++) {
1227 unsigned hash = rt_hash(daddr, skeys[i], ikeys[k],
1228 rt_genid(net));
1229
1230 rthp=&rt_hash_table[hash].chain;
1231
1232 rcu_read_lock();
1233 while ((rth = rcu_dereference(*rthp)) != NULL) {
1234 struct rtable *rt;
1235
1236 if (rth->fl.fl4_dst != daddr ||
1237 rth->fl.fl4_src != skeys[i] ||
1238 rth->fl.oif != ikeys[k] ||
1239 rth->fl.iif != 0 ||
1240 rt_is_expired(rth) ||
1241 !net_eq(dev_net(rth->u.dst.dev), net)) {
1242 rthp = &rth->u.dst.rt_next;
1243 continue;
1244 }
1245
1246 if (rth->rt_dst != daddr ||
1247 rth->rt_src != saddr ||
1248 rth->u.dst.error ||
1249 rth->rt_gateway != old_gw ||
1250 rth->u.dst.dev != dev)
1251 break;
1252
1253 dst_hold(&rth->u.dst);
1254 rcu_read_unlock();
1255
1256 rt = dst_alloc(&ipv4_dst_ops);
1257 if (rt == NULL) {
1258 ip_rt_put(rth);
1259 in_dev_put(in_dev);
1260 return;
1261 }
1262
1263 /* Copy all the information. */
1264 *rt = *rth;
1265 INIT_RCU_HEAD(&rt->u.dst.rcu_head);
1266 rt->u.dst.__use = 1;
1267 atomic_set(&rt->u.dst.__refcnt, 1);
1268 rt->u.dst.child = NULL;
1269 if (rt->u.dst.dev)
1270 dev_hold(rt->u.dst.dev);
1271 if (rt->idev)
1272 in_dev_hold(rt->idev);
1273 rt->u.dst.obsolete = 0;
1274 rt->u.dst.lastuse = jiffies;
1275 rt->u.dst.path = &rt->u.dst;
1276 rt->u.dst.neighbour = NULL;
1277 rt->u.dst.hh = NULL;
1278 rt->u.dst.xfrm = NULL;
1279 rt->rt_genid = rt_genid(net);
1280 rt->rt_flags |= RTCF_REDIRECTED;
1281
1282 /* Gateway is different ... */
1283 rt->rt_gateway = new_gw;
1284
1285 /* Redirect received -> path was valid */
1286 dst_confirm(&rth->u.dst);
1287
1288 if (rt->peer)
1289 atomic_inc(&rt->peer->refcnt);
1290
1291 if (arp_bind_neighbour(&rt->u.dst) ||
1292 !(rt->u.dst.neighbour->nud_state &
1293 NUD_VALID)) {
1294 if (rt->u.dst.neighbour)
1295 neigh_event_send(rt->u.dst.neighbour, NULL);
1296 ip_rt_put(rth);
1297 rt_drop(rt);
1298 goto do_next;
1299 }
1300
1301 netevent.old = &rth->u.dst;
1302 netevent.new = &rt->u.dst;
1303 call_netevent_notifiers(NETEVENT_REDIRECT,
1304 &netevent);
1305
1306 rt_del(hash, rth);
1307 if (!rt_intern_hash(hash, rt, &rt))
1308 ip_rt_put(rt);
1309 goto do_next;
1310 }
1311 rcu_read_unlock();
1312 do_next:
1313 ;
1314 }
1315 }
1316 in_dev_put(in_dev);
1317 return;
1318
1319 reject_redirect:
1320 #ifdef CONFIG_IP_ROUTE_VERBOSE
1321 if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit())
1322 printk(KERN_INFO "Redirect from " NIPQUAD_FMT " on %s about "
1323 NIPQUAD_FMT " ignored.\n"
1324 " Advised path = " NIPQUAD_FMT " -> " NIPQUAD_FMT "\n",
1325 NIPQUAD(old_gw), dev->name, NIPQUAD(new_gw),
1326 NIPQUAD(saddr), NIPQUAD(daddr));
1327 #endif
1328 in_dev_put(in_dev);
1329 }
1330
1331 static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
1332 {
1333 struct rtable *rt = (struct rtable *)dst;
1334 struct dst_entry *ret = dst;
1335
1336 if (rt) {
1337 if (dst->obsolete) {
1338 ip_rt_put(rt);
1339 ret = NULL;
1340 } else if ((rt->rt_flags & RTCF_REDIRECTED) ||
1341 rt->u.dst.expires) {
1342 unsigned hash = rt_hash(rt->fl.fl4_dst, rt->fl.fl4_src,
1343 rt->fl.oif,
1344 rt_genid(dev_net(dst->dev)));
1345 #if RT_CACHE_DEBUG >= 1
1346 printk(KERN_DEBUG "ipv4_negative_advice: redirect to "
1347 NIPQUAD_FMT "/%02x dropped\n",
1348 NIPQUAD(rt->rt_dst), rt->fl.fl4_tos);
1349 #endif
1350 rt_del(hash, rt);
1351 ret = NULL;
1352 }
1353 }
1354 return ret;
1355 }
1356
1357 /*
1358 * Algorithm:
1359 * 1. The first ip_rt_redirect_number redirects are sent
1360 * with exponential backoff, then we stop sending them at all,
1361 * assuming that the host ignores our redirects.
1362 * 2. If we did not see packets requiring redirects
1363 * during ip_rt_redirect_silence, we assume that the host
1364 * forgot redirected route and start to send redirects again.
1365 *
1366 * This algorithm is much cheaper and more intelligent than dumb load limiting
1367 * in icmp.c.
1368 *
1369 * NOTE. Do not forget to inhibit load limiting for redirects (redundant)
1370 * and "frag. need" (breaks PMTU discovery) in icmp.c.
1371 */
1372
1373 void ip_rt_send_redirect(struct sk_buff *skb)
1374 {
1375 struct rtable *rt = skb->rtable;
1376 struct in_device *in_dev = in_dev_get(rt->u.dst.dev);
1377
1378 if (!in_dev)
1379 return;
1380
1381 if (!IN_DEV_TX_REDIRECTS(in_dev))
1382 goto out;
1383
1384 /* No redirected packets during ip_rt_redirect_silence;
1385 * reset the algorithm.
1386 */
1387 if (time_after(jiffies, rt->u.dst.rate_last + ip_rt_redirect_silence))
1388 rt->u.dst.rate_tokens = 0;
1389
1390 /* Too many ignored redirects; do not send anything
1391 * set u.dst.rate_last to the last seen redirected packet.
1392 */
1393 if (rt->u.dst.rate_tokens >= ip_rt_redirect_number) {
1394 rt->u.dst.rate_last = jiffies;
1395 goto out;
1396 }
1397
1398 /* Check for load limit; set rate_last to the latest sent
1399 * redirect.
1400 */
1401 if (rt->u.dst.rate_tokens == 0 ||
1402 time_after(jiffies,
1403 (rt->u.dst.rate_last +
1404 (ip_rt_redirect_load << rt->u.dst.rate_tokens)))) {
1405 icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway);
1406 rt->u.dst.rate_last = jiffies;
1407 ++rt->u.dst.rate_tokens;
1408 #ifdef CONFIG_IP_ROUTE_VERBOSE
1409 if (IN_DEV_LOG_MARTIANS(in_dev) &&
1410 rt->u.dst.rate_tokens == ip_rt_redirect_number &&
1411 net_ratelimit())
1412 printk(KERN_WARNING "host " NIPQUAD_FMT "/if%d ignores "
1413 "redirects for " NIPQUAD_FMT " to " NIPQUAD_FMT ".\n",
1414 NIPQUAD(rt->rt_src), rt->rt_iif,
1415 NIPQUAD(rt->rt_dst), NIPQUAD(rt->rt_gateway));
1416 #endif
1417 }
1418 out:
1419 in_dev_put(in_dev);
1420 }
1421
1422 static int ip_error(struct sk_buff *skb)
1423 {
1424 struct rtable *rt = skb->rtable;
1425 unsigned long now;
1426 int code;
1427
1428 switch (rt->u.dst.error) {
1429 case EINVAL:
1430 default:
1431 goto out;
1432 case EHOSTUNREACH:
1433 code = ICMP_HOST_UNREACH;
1434 break;
1435 case ENETUNREACH:
1436 code = ICMP_NET_UNREACH;
1437 IP_INC_STATS_BH(dev_net(rt->u.dst.dev),
1438 IPSTATS_MIB_INNOROUTES);
1439 break;
1440 case EACCES:
1441 code = ICMP_PKT_FILTERED;
1442 break;
1443 }
1444
1445 now = jiffies;
1446 rt->u.dst.rate_tokens += now - rt->u.dst.rate_last;
1447 if (rt->u.dst.rate_tokens > ip_rt_error_burst)
1448 rt->u.dst.rate_tokens = ip_rt_error_burst;
1449 rt->u.dst.rate_last = now;
1450 if (rt->u.dst.rate_tokens >= ip_rt_error_cost) {
1451 rt->u.dst.rate_tokens -= ip_rt_error_cost;
1452 icmp_send(skb, ICMP_DEST_UNREACH, code, 0);
1453 }
1454
1455 out: kfree_skb(skb);
1456 return 0;
1457 }
1458
1459 /*
1460 * The last two values are not from the RFC but
1461 * are needed for AMPRnet AX.25 paths.
1462 */
1463
1464 static const unsigned short mtu_plateau[] =
1465 {32000, 17914, 8166, 4352, 2002, 1492, 576, 296, 216, 128 };
1466
1467 static inline unsigned short guess_mtu(unsigned short old_mtu)
1468 {
1469 int i;
1470
1471 for (i = 0; i < ARRAY_SIZE(mtu_plateau); i++)
1472 if (old_mtu > mtu_plateau[i])
1473 return mtu_plateau[i];
1474 return 68;
1475 }
1476
1477 unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph,
1478 unsigned short new_mtu,
1479 struct net_device *dev)
1480 {
1481 int i, k;
1482 unsigned short old_mtu = ntohs(iph->tot_len);
1483 struct rtable *rth;
1484 int ikeys[2] = { dev->ifindex, 0 };
1485 __be32 skeys[2] = { iph->saddr, 0, };
1486 __be32 daddr = iph->daddr;
1487 unsigned short est_mtu = 0;
1488
1489 if (ipv4_config.no_pmtu_disc)
1490 return 0;
1491
1492 for (k = 0; k < 2; k++) {
1493 for (i = 0; i < 2; i++) {
1494 unsigned hash = rt_hash(daddr, skeys[i], ikeys[k],
1495 rt_genid(net));
1496
1497 rcu_read_lock();
1498 for (rth = rcu_dereference(rt_hash_table[hash].chain); rth;
1499 rth = rcu_dereference(rth->u.dst.rt_next)) {
1500 unsigned short mtu = new_mtu;
1501
1502 if (rth->fl.fl4_dst != daddr ||
1503 rth->fl.fl4_src != skeys[i] ||
1504 rth->rt_dst != daddr ||
1505 rth->rt_src != iph->saddr ||
1506 rth->fl.oif != ikeys[k] ||
1507 rth->fl.iif != 0 ||
1508 dst_metric_locked(&rth->u.dst, RTAX_MTU) ||
1509 !net_eq(dev_net(rth->u.dst.dev), net) ||
1510 rt_is_expired(rth))
1511 continue;
1512
1513 if (new_mtu < 68 || new_mtu >= old_mtu) {
1514
1515 /* BSD 4.2 compatibility hack :-( */
1516 if (mtu == 0 &&
1517 old_mtu >= dst_mtu(&rth->u.dst) &&
1518 old_mtu >= 68 + (iph->ihl << 2))
1519 old_mtu -= iph->ihl << 2;
1520
1521 mtu = guess_mtu(old_mtu);
1522 }
1523 if (mtu <= dst_mtu(&rth->u.dst)) {
1524 if (mtu < dst_mtu(&rth->u.dst)) {
1525 dst_confirm(&rth->u.dst);
1526 if (mtu < ip_rt_min_pmtu) {
1527 mtu = ip_rt_min_pmtu;
1528 rth->u.dst.metrics[RTAX_LOCK-1] |=
1529 (1 << RTAX_MTU);
1530 }
1531 rth->u.dst.metrics[RTAX_MTU-1] = mtu;
1532 dst_set_expires(&rth->u.dst,
1533 ip_rt_mtu_expires);
1534 }
1535 est_mtu = mtu;
1536 }
1537 }
1538 rcu_read_unlock();
1539 }
1540 }
1541 return est_mtu ? : new_mtu;
1542 }
1543
1544 static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
1545 {
1546 if (dst_mtu(dst) > mtu && mtu >= 68 &&
1547 !(dst_metric_locked(dst, RTAX_MTU))) {
1548 if (mtu < ip_rt_min_pmtu) {
1549 mtu = ip_rt_min_pmtu;
1550 dst->metrics[RTAX_LOCK-1] |= (1 << RTAX_MTU);
1551 }
1552 dst->metrics[RTAX_MTU-1] = mtu;
1553 dst_set_expires(dst, ip_rt_mtu_expires);
1554 call_netevent_notifiers(NETEVENT_PMTU_UPDATE, dst);
1555 }
1556 }
1557
1558 static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
1559 {
1560 return NULL;
1561 }
1562
1563 static void ipv4_dst_destroy(struct dst_entry *dst)
1564 {
1565 struct rtable *rt = (struct rtable *) dst;
1566 struct inet_peer *peer = rt->peer;
1567 struct in_device *idev = rt->idev;
1568
1569 if (peer) {
1570 rt->peer = NULL;
1571 inet_putpeer(peer);
1572 }
1573
1574 if (idev) {
1575 rt->idev = NULL;
1576 in_dev_put(idev);
1577 }
1578 }
1579
1580 static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
1581 int how)
1582 {
1583 struct rtable *rt = (struct rtable *) dst;
1584 struct in_device *idev = rt->idev;
1585 if (dev != dev_net(dev)->loopback_dev && idev && idev->dev == dev) {
1586 struct in_device *loopback_idev =
1587 in_dev_get(dev_net(dev)->loopback_dev);
1588 if (loopback_idev) {
1589 rt->idev = loopback_idev;
1590 in_dev_put(idev);
1591 }
1592 }
1593 }
1594
1595 static void ipv4_link_failure(struct sk_buff *skb)
1596 {
1597 struct rtable *rt;
1598
1599 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
1600
1601 rt = skb->rtable;
1602 if (rt)
1603 dst_set_expires(&rt->u.dst, 0);
1604 }
1605
1606 static int ip_rt_bug(struct sk_buff *skb)
1607 {
1608 printk(KERN_DEBUG "ip_rt_bug: " NIPQUAD_FMT " -> " NIPQUAD_FMT ", %s\n",
1609 NIPQUAD(ip_hdr(skb)->saddr), NIPQUAD(ip_hdr(skb)->daddr),
1610 skb->dev ? skb->dev->name : "?");
1611 kfree_skb(skb);
1612 return 0;
1613 }
1614
1615 /*
1616 We do not cache source address of outgoing interface,
1617 because it is used only by IP RR, TS and SRR options,
1618 so that it out of fast path.
1619
1620 BTW remember: "addr" is allowed to be not aligned
1621 in IP options!
1622 */
1623
1624 void ip_rt_get_source(u8 *addr, struct rtable *rt)
1625 {
1626 __be32 src;
1627 struct fib_result res;
1628
1629 if (rt->fl.iif == 0)
1630 src = rt->rt_src;
1631 else if (fib_lookup(dev_net(rt->u.dst.dev), &rt->fl, &res) == 0) {
1632 src = FIB_RES_PREFSRC(res);
1633 fib_res_put(&res);
1634 } else
1635 src = inet_select_addr(rt->u.dst.dev, rt->rt_gateway,
1636 RT_SCOPE_UNIVERSE);
1637 memcpy(addr, &src, 4);
1638 }
1639
1640 #ifdef CONFIG_NET_CLS_ROUTE
1641 static void set_class_tag(struct rtable *rt, u32 tag)
1642 {
1643 if (!(rt->u.dst.tclassid & 0xFFFF))
1644 rt->u.dst.tclassid |= tag & 0xFFFF;
1645 if (!(rt->u.dst.tclassid & 0xFFFF0000))
1646 rt->u.dst.tclassid |= tag & 0xFFFF0000;
1647 }
1648 #endif
1649
1650 static void rt_set_nexthop(struct rtable *rt, struct fib_result *res, u32 itag)
1651 {
1652 struct fib_info *fi = res->fi;
1653
1654 if (fi) {
1655 if (FIB_RES_GW(*res) &&
1656 FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
1657 rt->rt_gateway = FIB_RES_GW(*res);
1658 memcpy(rt->u.dst.metrics, fi->fib_metrics,
1659 sizeof(rt->u.dst.metrics));
1660 if (fi->fib_mtu == 0) {
1661 rt->u.dst.metrics[RTAX_MTU-1] = rt->u.dst.dev->mtu;
1662 if (dst_metric_locked(&rt->u.dst, RTAX_MTU) &&
1663 rt->rt_gateway != rt->rt_dst &&
1664 rt->u.dst.dev->mtu > 576)
1665 rt->u.dst.metrics[RTAX_MTU-1] = 576;
1666 }
1667 #ifdef CONFIG_NET_CLS_ROUTE
1668 rt->u.dst.tclassid = FIB_RES_NH(*res).nh_tclassid;
1669 #endif
1670 } else
1671 rt->u.dst.metrics[RTAX_MTU-1]= rt->u.dst.dev->mtu;
1672
1673 if (dst_metric(&rt->u.dst, RTAX_HOPLIMIT) == 0)
1674 rt->u.dst.metrics[RTAX_HOPLIMIT-1] = sysctl_ip_default_ttl;
1675 if (dst_mtu(&rt->u.dst) > IP_MAX_MTU)
1676 rt->u.dst.metrics[RTAX_MTU-1] = IP_MAX_MTU;
1677 if (dst_metric(&rt->u.dst, RTAX_ADVMSS) == 0)
1678 rt->u.dst.metrics[RTAX_ADVMSS-1] = max_t(unsigned int, rt->u.dst.dev->mtu - 40,
1679 ip_rt_min_advmss);
1680 if (dst_metric(&rt->u.dst, RTAX_ADVMSS) > 65535 - 40)
1681 rt->u.dst.metrics[RTAX_ADVMSS-1] = 65535 - 40;
1682
1683 #ifdef CONFIG_NET_CLS_ROUTE
1684 #ifdef CONFIG_IP_MULTIPLE_TABLES
1685 set_class_tag(rt, fib_rules_tclass(res));
1686 #endif
1687 set_class_tag(rt, itag);
1688 #endif
1689 rt->rt_type = res->type;
1690 }
1691
1692 static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1693 u8 tos, struct net_device *dev, int our)
1694 {
1695 unsigned hash;
1696 struct rtable *rth;
1697 __be32 spec_dst;
1698 struct in_device *in_dev = in_dev_get(dev);
1699 u32 itag = 0;
1700
1701 /* Primary sanity checks. */
1702
1703 if (in_dev == NULL)
1704 return -EINVAL;
1705
1706 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) ||
1707 ipv4_is_loopback(saddr) || skb->protocol != htons(ETH_P_IP))
1708 goto e_inval;
1709
1710 if (ipv4_is_zeronet(saddr)) {
1711 if (!ipv4_is_local_multicast(daddr))
1712 goto e_inval;
1713 spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK);
1714 } else if (fib_validate_source(saddr, 0, tos, 0,
1715 dev, &spec_dst, &itag) < 0)
1716 goto e_inval;
1717
1718 rth = dst_alloc(&ipv4_dst_ops);
1719 if (!rth)
1720 goto e_nobufs;
1721
1722 rth->u.dst.output= ip_rt_bug;
1723
1724 atomic_set(&rth->u.dst.__refcnt, 1);
1725 rth->u.dst.flags= DST_HOST;
1726 if (IN_DEV_CONF_GET(in_dev, NOPOLICY))
1727 rth->u.dst.flags |= DST_NOPOLICY;
1728 rth->fl.fl4_dst = daddr;
1729 rth->rt_dst = daddr;
1730 rth->fl.fl4_tos = tos;
1731 rth->fl.mark = skb->mark;
1732 rth->fl.fl4_src = saddr;
1733 rth->rt_src = saddr;
1734 #ifdef CONFIG_NET_CLS_ROUTE
1735 rth->u.dst.tclassid = itag;
1736 #endif
1737 rth->rt_iif =
1738 rth->fl.iif = dev->ifindex;
1739 rth->u.dst.dev = init_net.loopback_dev;
1740 dev_hold(rth->u.dst.dev);
1741 rth->idev = in_dev_get(rth->u.dst.dev);
1742 rth->fl.oif = 0;
1743 rth->rt_gateway = daddr;
1744 rth->rt_spec_dst= spec_dst;
1745 rth->rt_genid = rt_genid(dev_net(dev));
1746 rth->rt_flags = RTCF_MULTICAST;
1747 rth->rt_type = RTN_MULTICAST;
1748 if (our) {
1749 rth->u.dst.input= ip_local_deliver;
1750 rth->rt_flags |= RTCF_LOCAL;
1751 }
1752
1753 #ifdef CONFIG_IP_MROUTE
1754 if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev))
1755 rth->u.dst.input = ip_mr_input;
1756 #endif
1757 RT_CACHE_STAT_INC(in_slow_mc);
1758
1759 in_dev_put(in_dev);
1760 hash = rt_hash(daddr, saddr, dev->ifindex, rt_genid(dev_net(dev)));
1761 return rt_intern_hash(hash, rth, &skb->rtable);
1762
1763 e_nobufs:
1764 in_dev_put(in_dev);
1765 return -ENOBUFS;
1766
1767 e_inval:
1768 in_dev_put(in_dev);
1769 return -EINVAL;
1770 }
1771
1772
1773 static void ip_handle_martian_source(struct net_device *dev,
1774 struct in_device *in_dev,
1775 struct sk_buff *skb,
1776 __be32 daddr,
1777 __be32 saddr)
1778 {
1779 RT_CACHE_STAT_INC(in_martian_src);
1780 #ifdef CONFIG_IP_ROUTE_VERBOSE
1781 if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) {
1782 /*
1783 * RFC1812 recommendation, if source is martian,
1784 * the only hint is MAC header.
1785 */
1786 printk(KERN_WARNING "martian source " NIPQUAD_FMT " from "
1787 NIPQUAD_FMT", on dev %s\n",
1788 NIPQUAD(daddr), NIPQUAD(saddr), dev->name);
1789 if (dev->hard_header_len && skb_mac_header_was_set(skb)) {
1790 int i;
1791 const unsigned char *p = skb_mac_header(skb);
1792 printk(KERN_WARNING "ll header: ");
1793 for (i = 0; i < dev->hard_header_len; i++, p++) {
1794 printk("%02x", *p);
1795 if (i < (dev->hard_header_len - 1))
1796 printk(":");
1797 }
1798 printk("\n");
1799 }
1800 }
1801 #endif
1802 }
1803
1804 static int __mkroute_input(struct sk_buff *skb,
1805 struct fib_result *res,
1806 struct in_device *in_dev,
1807 __be32 daddr, __be32 saddr, u32 tos,
1808 struct rtable **result)
1809 {
1810
1811 struct rtable *rth;
1812 int err;
1813 struct in_device *out_dev;
1814 unsigned flags = 0;
1815 __be32 spec_dst;
1816 u32 itag;
1817
1818 /* get a working reference to the output device */
1819 out_dev = in_dev_get(FIB_RES_DEV(*res));
1820 if (out_dev == NULL) {
1821 if (net_ratelimit())
1822 printk(KERN_CRIT "Bug in ip_route_input" \
1823 "_slow(). Please, report\n");
1824 return -EINVAL;
1825 }
1826
1827
1828 err = fib_validate_source(saddr, daddr, tos, FIB_RES_OIF(*res),
1829 in_dev->dev, &spec_dst, &itag);
1830 if (err < 0) {
1831 ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr,
1832 saddr);
1833
1834 err = -EINVAL;
1835 goto cleanup;
1836 }
1837
1838 if (err)
1839 flags |= RTCF_DIRECTSRC;
1840
1841 if (out_dev == in_dev && err &&
1842 (IN_DEV_SHARED_MEDIA(out_dev) ||
1843 inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res))))
1844 flags |= RTCF_DOREDIRECT;
1845
1846 if (skb->protocol != htons(ETH_P_IP)) {
1847 /* Not IP (i.e. ARP). Do not create route, if it is
1848 * invalid for proxy arp. DNAT routes are always valid.
1849 */
1850 if (out_dev == in_dev) {
1851 err = -EINVAL;
1852 goto cleanup;
1853 }
1854 }
1855
1856
1857 rth = dst_alloc(&ipv4_dst_ops);
1858 if (!rth) {
1859 err = -ENOBUFS;
1860 goto cleanup;
1861 }
1862
1863 atomic_set(&rth->u.dst.__refcnt, 1);
1864 rth->u.dst.flags= DST_HOST;
1865 if (IN_DEV_CONF_GET(in_dev, NOPOLICY))
1866 rth->u.dst.flags |= DST_NOPOLICY;
1867 if (IN_DEV_CONF_GET(out_dev, NOXFRM))
1868 rth->u.dst.flags |= DST_NOXFRM;
1869 rth->fl.fl4_dst = daddr;
1870 rth->rt_dst = daddr;
1871 rth->fl.fl4_tos = tos;
1872 rth->fl.mark = skb->mark;
1873 rth->fl.fl4_src = saddr;
1874 rth->rt_src = saddr;
1875 rth->rt_gateway = daddr;
1876 rth->rt_iif =
1877 rth->fl.iif = in_dev->dev->ifindex;
1878 rth->u.dst.dev = (out_dev)->dev;
1879 dev_hold(rth->u.dst.dev);
1880 rth->idev = in_dev_get(rth->u.dst.dev);
1881 rth->fl.oif = 0;
1882 rth->rt_spec_dst= spec_dst;
1883
1884 rth->u.dst.input = ip_forward;
1885 rth->u.dst.output = ip_output;
1886 rth->rt_genid = rt_genid(dev_net(rth->u.dst.dev));
1887
1888 rt_set_nexthop(rth, res, itag);
1889
1890 rth->rt_flags = flags;
1891
1892 *result = rth;
1893 err = 0;
1894 cleanup:
1895 /* release the working reference to the output device */
1896 in_dev_put(out_dev);
1897 return err;
1898 }
1899
1900 static int ip_mkroute_input(struct sk_buff *skb,
1901 struct fib_result *res,
1902 const struct flowi *fl,
1903 struct in_device *in_dev,
1904 __be32 daddr, __be32 saddr, u32 tos)
1905 {
1906 struct rtable* rth = NULL;
1907 int err;
1908 unsigned hash;
1909
1910 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1911 if (res->fi && res->fi->fib_nhs > 1 && fl->oif == 0)
1912 fib_select_multipath(fl, res);
1913 #endif
1914
1915 /* create a routing cache entry */
1916 err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, &rth);
1917 if (err)
1918 return err;
1919
1920 /* put it into the cache */
1921 hash = rt_hash(daddr, saddr, fl->iif,
1922 rt_genid(dev_net(rth->u.dst.dev)));
1923 return rt_intern_hash(hash, rth, &skb->rtable);
1924 }
1925
1926 /*
1927 * NOTE. We drop all the packets that has local source
1928 * addresses, because every properly looped back packet
1929 * must have correct destination already attached by output routine.
1930 *
1931 * Such approach solves two big problems:
1932 * 1. Not simplex devices are handled properly.
1933 * 2. IP spoofing attempts are filtered with 100% of guarantee.
1934 */
1935
1936 static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
1937 u8 tos, struct net_device *dev)
1938 {
1939 struct fib_result res;
1940 struct in_device *in_dev = in_dev_get(dev);
1941 struct flowi fl = { .nl_u = { .ip4_u =
1942 { .daddr = daddr,
1943 .saddr = saddr,
1944 .tos = tos,
1945 .scope = RT_SCOPE_UNIVERSE,
1946 } },
1947 .mark = skb->mark,
1948 .iif = dev->ifindex };
1949 unsigned flags = 0;
1950 u32 itag = 0;
1951 struct rtable * rth;
1952 unsigned hash;
1953 __be32 spec_dst;
1954 int err = -EINVAL;
1955 int free_res = 0;
1956 struct net * net = dev_net(dev);
1957
1958 /* IP on this device is disabled. */
1959
1960 if (!in_dev)
1961 goto out;
1962
1963 /* Check for the most weird martians, which can be not detected
1964 by fib_lookup.
1965 */
1966
1967 if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) ||
1968 ipv4_is_loopback(saddr))
1969 goto martian_source;
1970
1971 if (daddr == htonl(0xFFFFFFFF) || (saddr == 0 && daddr == 0))
1972 goto brd_input;
1973
1974 /* Accept zero addresses only to limited broadcast;
1975 * I even do not know to fix it or not. Waiting for complains :-)
1976 */
1977 if (ipv4_is_zeronet(saddr))
1978 goto martian_source;
1979
1980 if (ipv4_is_lbcast(daddr) || ipv4_is_zeronet(daddr) ||
1981 ipv4_is_loopback(daddr))
1982 goto martian_destination;
1983
1984 /*
1985 * Now we are ready to route packet.
1986 */
1987 if ((err = fib_lookup(net, &fl, &res)) != 0) {
1988 if (!IN_DEV_FORWARD(in_dev))
1989 goto e_hostunreach;
1990 goto no_route;
1991 }
1992 free_res = 1;
1993
1994 RT_CACHE_STAT_INC(in_slow_tot);
1995
1996 if (res.type == RTN_BROADCAST)
1997 goto brd_input;
1998
1999 if (res.type == RTN_LOCAL) {
2000 int result;
2001 result = fib_validate_source(saddr, daddr, tos,
2002 net->loopback_dev->ifindex,
2003 dev, &spec_dst, &itag);
2004 if (result < 0)
2005 goto martian_source;
2006 if (result)
2007 flags |= RTCF_DIRECTSRC;
2008 spec_dst = daddr;
2009 goto local_input;
2010 }
2011
2012 if (!IN_DEV_FORWARD(in_dev))
2013 goto e_hostunreach;
2014 if (res.type != RTN_UNICAST)
2015 goto martian_destination;
2016
2017 err = ip_mkroute_input(skb, &res, &fl, in_dev, daddr, saddr, tos);
2018 done:
2019 in_dev_put(in_dev);
2020 if (free_res)
2021 fib_res_put(&res);
2022 out: return err;
2023
2024 brd_input:
2025 if (skb->protocol != htons(ETH_P_IP))
2026 goto e_inval;
2027
2028 if (ipv4_is_zeronet(saddr))
2029 spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK);
2030 else {
2031 err = fib_validate_source(saddr, 0, tos, 0, dev, &spec_dst,
2032 &itag);
2033 if (err < 0)
2034 goto martian_source;
2035 if (err)
2036 flags |= RTCF_DIRECTSRC;
2037 }
2038 flags |= RTCF_BROADCAST;
2039 res.type = RTN_BROADCAST;
2040 RT_CACHE_STAT_INC(in_brd);
2041
2042 local_input:
2043 rth = dst_alloc(&ipv4_dst_ops);
2044 if (!rth)
2045 goto e_nobufs;
2046
2047 rth->u.dst.output= ip_rt_bug;
2048 rth->rt_genid = rt_genid(net);
2049
2050 atomic_set(&rth->u.dst.__refcnt, 1);
2051 rth->u.dst.flags= DST_HOST;
2052 if (IN_DEV_CONF_GET(in_dev, NOPOLICY))
2053 rth->u.dst.flags |= DST_NOPOLICY;
2054 rth->fl.fl4_dst = daddr;
2055 rth->rt_dst = daddr;
2056 rth->fl.fl4_tos = tos;
2057 rth->fl.mark = skb->mark;
2058 rth->fl.fl4_src = saddr;
2059 rth->rt_src = saddr;
2060 #ifdef CONFIG_NET_CLS_ROUTE
2061 rth->u.dst.tclassid = itag;
2062 #endif
2063 rth->rt_iif =
2064 rth->fl.iif = dev->ifindex;
2065 rth->u.dst.dev = net->loopback_dev;
2066 dev_hold(rth->u.dst.dev);
2067 rth->idev = in_dev_get(rth->u.dst.dev);
2068 rth->rt_gateway = daddr;
2069 rth->rt_spec_dst= spec_dst;
2070 rth->u.dst.input= ip_local_deliver;
2071 rth->rt_flags = flags|RTCF_LOCAL;
2072 if (res.type == RTN_UNREACHABLE) {
2073 rth->u.dst.input= ip_error;
2074 rth->u.dst.error= -err;
2075 rth->rt_flags &= ~RTCF_LOCAL;
2076 }
2077 rth->rt_type = res.type;
2078 hash = rt_hash(daddr, saddr, fl.iif, rt_genid(net));
2079 err = rt_intern_hash(hash, rth, &skb->rtable);
2080 goto done;
2081
2082 no_route:
2083 RT_CACHE_STAT_INC(in_no_route);
2084 spec_dst = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE);
2085 res.type = RTN_UNREACHABLE;
2086 if (err == -ESRCH)
2087 err = -ENETUNREACH;
2088 goto local_input;
2089
2090 /*
2091 * Do not cache martian addresses: they should be logged (RFC1812)
2092 */
2093 martian_destination:
2094 RT_CACHE_STAT_INC(in_martian_dst);
2095 #ifdef CONFIG_IP_ROUTE_VERBOSE
2096 if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit())
2097 printk(KERN_WARNING "martian destination " NIPQUAD_FMT " from "
2098 NIPQUAD_FMT ", dev %s\n",
2099 NIPQUAD(daddr), NIPQUAD(saddr), dev->name);
2100 #endif
2101
2102 e_hostunreach:
2103 err = -EHOSTUNREACH;
2104 goto done;
2105
2106 e_inval:
2107 err = -EINVAL;
2108 goto done;
2109
2110 e_nobufs:
2111 err = -ENOBUFS;
2112 goto done;
2113
2114 martian_source:
2115 ip_handle_martian_source(dev, in_dev, skb, daddr, saddr);
2116 goto e_inval;
2117 }
2118
2119 int ip_route_input(struct sk_buff *skb, __be32 daddr, __be32 saddr,
2120 u8 tos, struct net_device *dev)
2121 {
2122 struct rtable * rth;
2123 unsigned hash;
2124 int iif = dev->ifindex;
2125 struct net *net;
2126
2127 net = dev_net(dev);
2128 tos &= IPTOS_RT_MASK;
2129 hash = rt_hash(daddr, saddr, iif, rt_genid(net));
2130
2131 rcu_read_lock();
2132 for (rth = rcu_dereference(rt_hash_table[hash].chain); rth;
2133 rth = rcu_dereference(rth->u.dst.rt_next)) {
2134 if (((rth->fl.fl4_dst ^ daddr) |
2135 (rth->fl.fl4_src ^ saddr) |
2136 (rth->fl.iif ^ iif) |
2137 rth->fl.oif |
2138 (rth->fl.fl4_tos ^ tos)) == 0 &&
2139 rth->fl.mark == skb->mark &&
2140 net_eq(dev_net(rth->u.dst.dev), net) &&
2141 !rt_is_expired(rth)) {
2142 dst_use(&rth->u.dst, jiffies);
2143 RT_CACHE_STAT_INC(in_hit);
2144 rcu_read_unlock();
2145 skb->rtable = rth;
2146 return 0;
2147 }
2148 RT_CACHE_STAT_INC(in_hlist_search);
2149 }
2150 rcu_read_unlock();
2151
2152 /* Multicast recognition logic is moved from route cache to here.
2153 The problem was that too many Ethernet cards have broken/missing
2154 hardware multicast filters :-( As result the host on multicasting
2155 network acquires a lot of useless route cache entries, sort of
2156 SDR messages from all the world. Now we try to get rid of them.
2157 Really, provided software IP multicast filter is organized
2158 reasonably (at least, hashed), it does not result in a slowdown
2159 comparing with route cache reject entries.
2160 Note, that multicast routers are not affected, because
2161 route cache entry is created eventually.
2162 */
2163 if (ipv4_is_multicast(daddr)) {
2164 struct in_device *in_dev;
2165
2166 rcu_read_lock();
2167 if ((in_dev = __in_dev_get_rcu(dev)) != NULL) {
2168 int our = ip_check_mc(in_dev, daddr, saddr,
2169 ip_hdr(skb)->protocol);
2170 if (our
2171 #ifdef CONFIG_IP_MROUTE
2172 || (!ipv4_is_local_multicast(daddr) &&
2173 IN_DEV_MFORWARD(in_dev))
2174 #endif
2175 ) {
2176 rcu_read_unlock();
2177 return ip_route_input_mc(skb, daddr, saddr,
2178 tos, dev, our);
2179 }
2180 }
2181 rcu_read_unlock();
2182 return -EINVAL;
2183 }
2184 return ip_route_input_slow(skb, daddr, saddr, tos, dev);
2185 }
2186
2187 static int __mkroute_output(struct rtable **result,
2188 struct fib_result *res,
2189 const struct flowi *fl,
2190 const struct flowi *oldflp,
2191 struct net_device *dev_out,
2192 unsigned flags)
2193 {
2194 struct rtable *rth;
2195 struct in_device *in_dev;
2196 u32 tos = RT_FL_TOS(oldflp);
2197 int err = 0;
2198
2199 if (ipv4_is_loopback(fl->fl4_src) && !(dev_out->flags&IFF_LOOPBACK))
2200 return -EINVAL;
2201
2202 if (fl->fl4_dst == htonl(0xFFFFFFFF))
2203 res->type = RTN_BROADCAST;
2204 else if (ipv4_is_multicast(fl->fl4_dst))
2205 res->type = RTN_MULTICAST;
2206 else if (ipv4_is_lbcast(fl->fl4_dst) || ipv4_is_zeronet(fl->fl4_dst))
2207 return -EINVAL;
2208
2209 if (dev_out->flags & IFF_LOOPBACK)
2210 flags |= RTCF_LOCAL;
2211
2212 /* get work reference to inet device */
2213 in_dev = in_dev_get(dev_out);
2214 if (!in_dev)
2215 return -EINVAL;
2216
2217 if (res->type == RTN_BROADCAST) {
2218 flags |= RTCF_BROADCAST | RTCF_LOCAL;
2219 if (res->fi) {
2220 fib_info_put(res->fi);
2221 res->fi = NULL;
2222 }
2223 } else if (res->type == RTN_MULTICAST) {
2224 flags |= RTCF_MULTICAST|RTCF_LOCAL;
2225 if (!ip_check_mc(in_dev, oldflp->fl4_dst, oldflp->fl4_src,
2226 oldflp->proto))
2227 flags &= ~RTCF_LOCAL;
2228 /* If multicast route do not exist use
2229 default one, but do not gateway in this case.
2230 Yes, it is hack.
2231 */
2232 if (res->fi && res->prefixlen < 4) {
2233 fib_info_put(res->fi);
2234 res->fi = NULL;
2235 }
2236 }
2237
2238
2239 rth = dst_alloc(&ipv4_dst_ops);
2240 if (!rth) {
2241 err = -ENOBUFS;
2242 goto cleanup;
2243 }
2244
2245 atomic_set(&rth->u.dst.__refcnt, 1);
2246 rth->u.dst.flags= DST_HOST;
2247 if (IN_DEV_CONF_GET(in_dev, NOXFRM))
2248 rth->u.dst.flags |= DST_NOXFRM;
2249 if (IN_DEV_CONF_GET(in_dev, NOPOLICY))
2250 rth->u.dst.flags |= DST_NOPOLICY;
2251
2252 rth->fl.fl4_dst = oldflp->fl4_dst;
2253 rth->fl.fl4_tos = tos;
2254 rth->fl.fl4_src = oldflp->fl4_src;
2255 rth->fl.oif = oldflp->oif;
2256 rth->fl.mark = oldflp->mark;
2257 rth->rt_dst = fl->fl4_dst;
2258 rth->rt_src = fl->fl4_src;
2259 rth->rt_iif = oldflp->oif ? : dev_out->ifindex;
2260 /* get references to the devices that are to be hold by the routing
2261 cache entry */
2262 rth->u.dst.dev = dev_out;
2263 dev_hold(dev_out);
2264 rth->idev = in_dev_get(dev_out);
2265 rth->rt_gateway = fl->fl4_dst;
2266 rth->rt_spec_dst= fl->fl4_src;
2267
2268 rth->u.dst.output=ip_output;
2269 rth->rt_genid = rt_genid(dev_net(dev_out));
2270
2271 RT_CACHE_STAT_INC(out_slow_tot);
2272
2273 if (flags & RTCF_LOCAL) {
2274 rth->u.dst.input = ip_local_deliver;
2275 rth->rt_spec_dst = fl->fl4_dst;
2276 }
2277 if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) {
2278 rth->rt_spec_dst = fl->fl4_src;
2279 if (flags & RTCF_LOCAL &&
2280 !(dev_out->flags & IFF_LOOPBACK)) {
2281 rth->u.dst.output = ip_mc_output;
2282 RT_CACHE_STAT_INC(out_slow_mc);
2283 }
2284 #ifdef CONFIG_IP_MROUTE
2285 if (res->type == RTN_MULTICAST) {
2286 if (IN_DEV_MFORWARD(in_dev) &&
2287 !ipv4_is_local_multicast(oldflp->fl4_dst)) {
2288 rth->u.dst.input = ip_mr_input;
2289 rth->u.dst.output = ip_mc_output;
2290 }
2291 }
2292 #endif
2293 }
2294
2295 rt_set_nexthop(rth, res, 0);
2296
2297 rth->rt_flags = flags;
2298
2299 *result = rth;
2300 cleanup:
2301 /* release work reference to inet device */
2302 in_dev_put(in_dev);
2303
2304 return err;
2305 }
2306
2307 static int ip_mkroute_output(struct rtable **rp,
2308 struct fib_result *res,
2309 const struct flowi *fl,
2310 const struct flowi *oldflp,
2311 struct net_device *dev_out,
2312 unsigned flags)
2313 {
2314 struct rtable *rth = NULL;
2315 int err = __mkroute_output(&rth, res, fl, oldflp, dev_out, flags);
2316 unsigned hash;
2317 if (err == 0) {
2318 hash = rt_hash(oldflp->fl4_dst, oldflp->fl4_src, oldflp->oif,
2319 rt_genid(dev_net(dev_out)));
2320 err = rt_intern_hash(hash, rth, rp);
2321 }
2322
2323 return err;
2324 }
2325
2326 /*
2327 * Major route resolver routine.
2328 */
2329
2330 static int ip_route_output_slow(struct net *net, struct rtable **rp,
2331 const struct flowi *oldflp)
2332 {
2333 u32 tos = RT_FL_TOS(oldflp);
2334 struct flowi fl = { .nl_u = { .ip4_u =
2335 { .daddr = oldflp->fl4_dst,
2336 .saddr = oldflp->fl4_src,
2337 .tos = tos & IPTOS_RT_MASK,
2338 .scope = ((tos & RTO_ONLINK) ?
2339 RT_SCOPE_LINK :
2340 RT_SCOPE_UNIVERSE),
2341 } },
2342 .mark = oldflp->mark,
2343 .iif = net->loopback_dev->ifindex,
2344 .oif = oldflp->oif };
2345 struct fib_result res;
2346 unsigned flags = 0;
2347 struct net_device *dev_out = NULL;
2348 int free_res = 0;
2349 int err;
2350
2351
2352 res.fi = NULL;
2353 #ifdef CONFIG_IP_MULTIPLE_TABLES
2354 res.r = NULL;
2355 #endif
2356
2357 if (oldflp->fl4_src) {
2358 err = -EINVAL;
2359 if (ipv4_is_multicast(oldflp->fl4_src) ||
2360 ipv4_is_lbcast(oldflp->fl4_src) ||
2361 ipv4_is_zeronet(oldflp->fl4_src))
2362 goto out;
2363
2364 /* I removed check for oif == dev_out->oif here.
2365 It was wrong for two reasons:
2366 1. ip_dev_find(net, saddr) can return wrong iface, if saddr
2367 is assigned to multiple interfaces.
2368 2. Moreover, we are allowed to send packets with saddr
2369 of another iface. --ANK
2370 */
2371
2372 if (oldflp->oif == 0
2373 && (ipv4_is_multicast(oldflp->fl4_dst) ||
2374 oldflp->fl4_dst == htonl(0xFFFFFFFF))) {
2375 /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
2376 dev_out = ip_dev_find(net, oldflp->fl4_src);
2377 if (dev_out == NULL)
2378 goto out;
2379
2380 /* Special hack: user can direct multicasts
2381 and limited broadcast via necessary interface
2382 without fiddling with IP_MULTICAST_IF or IP_PKTINFO.
2383 This hack is not just for fun, it allows
2384 vic,vat and friends to work.
2385 They bind socket to loopback, set ttl to zero
2386 and expect that it will work.
2387 From the viewpoint of routing cache they are broken,
2388 because we are not allowed to build multicast path
2389 with loopback source addr (look, routing cache
2390 cannot know, that ttl is zero, so that packet
2391 will not leave this host and route is valid).
2392 Luckily, this hack is good workaround.
2393 */
2394
2395 fl.oif = dev_out->ifindex;
2396 goto make_route;
2397 }
2398
2399 if (!(oldflp->flags & FLOWI_FLAG_ANYSRC)) {
2400 /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
2401 dev_out = ip_dev_find(net, oldflp->fl4_src);
2402 if (dev_out == NULL)
2403 goto out;
2404 dev_put(dev_out);
2405 dev_out = NULL;
2406 }
2407 }
2408
2409
2410 if (oldflp->oif) {
2411 dev_out = dev_get_by_index(net, oldflp->oif);
2412 err = -ENODEV;
2413 if (dev_out == NULL)
2414 goto out;
2415
2416 /* RACE: Check return value of inet_select_addr instead. */
2417 if (__in_dev_get_rtnl(dev_out) == NULL) {
2418 dev_put(dev_out);
2419 goto out; /* Wrong error code */
2420 }
2421
2422 if (ipv4_is_local_multicast(oldflp->fl4_dst) ||
2423 oldflp->fl4_dst == htonl(0xFFFFFFFF)) {
2424 if (!fl.fl4_src)
2425 fl.fl4_src = inet_select_addr(dev_out, 0,
2426 RT_SCOPE_LINK);
2427 goto make_route;
2428 }
2429 if (!fl.fl4_src) {
2430 if (ipv4_is_multicast(oldflp->fl4_dst))
2431 fl.fl4_src = inet_select_addr(dev_out, 0,
2432 fl.fl4_scope);
2433 else if (!oldflp->fl4_dst)
2434 fl.fl4_src = inet_select_addr(dev_out, 0,
2435 RT_SCOPE_HOST);
2436 }
2437 }
2438
2439 if (!fl.fl4_dst) {
2440 fl.fl4_dst = fl.fl4_src;
2441 if (!fl.fl4_dst)
2442 fl.fl4_dst = fl.fl4_src = htonl(INADDR_LOOPBACK);
2443 if (dev_out)
2444 dev_put(dev_out);
2445 dev_out = net->loopback_dev;
2446 dev_hold(dev_out);
2447 fl.oif = net->loopback_dev->ifindex;
2448 res.type = RTN_LOCAL;
2449 flags |= RTCF_LOCAL;
2450 goto make_route;
2451 }
2452
2453 if (fib_lookup(net, &fl, &res)) {
2454 res.fi = NULL;
2455 if (oldflp->oif) {
2456 /* Apparently, routing tables are wrong. Assume,
2457 that the destination is on link.
2458
2459 WHY? DW.
2460 Because we are allowed to send to iface
2461 even if it has NO routes and NO assigned
2462 addresses. When oif is specified, routing
2463 tables are looked up with only one purpose:
2464 to catch if destination is gatewayed, rather than
2465 direct. Moreover, if MSG_DONTROUTE is set,
2466 we send packet, ignoring both routing tables
2467 and ifaddr state. --ANK
2468
2469
2470 We could make it even if oif is unknown,
2471 likely IPv6, but we do not.
2472 */
2473
2474 if (fl.fl4_src == 0)
2475 fl.fl4_src = inet_select_addr(dev_out, 0,
2476 RT_SCOPE_LINK);
2477 res.type = RTN_UNICAST;
2478 goto make_route;
2479 }
2480 if (dev_out)
2481 dev_put(dev_out);
2482 err = -ENETUNREACH;
2483 goto out;
2484 }
2485 free_res = 1;
2486
2487 if (res.type == RTN_LOCAL) {
2488 if (!fl.fl4_src)
2489 fl.fl4_src = fl.fl4_dst;
2490 if (dev_out)
2491 dev_put(dev_out);
2492 dev_out = net->loopback_dev;
2493 dev_hold(dev_out);
2494 fl.oif = dev_out->ifindex;
2495 if (res.fi)
2496 fib_info_put(res.fi);
2497 res.fi = NULL;
2498 flags |= RTCF_LOCAL;
2499 goto make_route;
2500 }
2501
2502 #ifdef CONFIG_IP_ROUTE_MULTIPATH
2503 if (res.fi->fib_nhs > 1 && fl.oif == 0)
2504 fib_select_multipath(&fl, &res);
2505 else
2506 #endif
2507 if (!res.prefixlen && res.type == RTN_UNICAST && !fl.oif)
2508 fib_select_default(net, &fl, &res);
2509
2510 if (!fl.fl4_src)
2511 fl.fl4_src = FIB_RES_PREFSRC(res);
2512
2513 if (dev_out)
2514 dev_put(dev_out);
2515 dev_out = FIB_RES_DEV(res);
2516 dev_hold(dev_out);
2517 fl.oif = dev_out->ifindex;
2518
2519
2520 make_route:
2521 err = ip_mkroute_output(rp, &res, &fl, oldflp, dev_out, flags);
2522
2523
2524 if (free_res)
2525 fib_res_put(&res);
2526 if (dev_out)
2527 dev_put(dev_out);
2528 out: return err;
2529 }
2530
2531 int __ip_route_output_key(struct net *net, struct rtable **rp,
2532 const struct flowi *flp)
2533 {
2534 unsigned hash;
2535 struct rtable *rth;
2536
2537 hash = rt_hash(flp->fl4_dst, flp->fl4_src, flp->oif, rt_genid(net));
2538
2539 rcu_read_lock_bh();
2540 for (rth = rcu_dereference(rt_hash_table[hash].chain); rth;
2541 rth = rcu_dereference(rth->u.dst.rt_next)) {
2542 if (rth->fl.fl4_dst == flp->fl4_dst &&
2543 rth->fl.fl4_src == flp->fl4_src &&
2544 rth->fl.iif == 0 &&
2545 rth->fl.oif == flp->oif &&
2546 rth->fl.mark == flp->mark &&
2547 !((rth->fl.fl4_tos ^ flp->fl4_tos) &
2548 (IPTOS_RT_MASK | RTO_ONLINK)) &&
2549 net_eq(dev_net(rth->u.dst.dev), net) &&
2550 !rt_is_expired(rth)) {
2551 dst_use(&rth->u.dst, jiffies);
2552 RT_CACHE_STAT_INC(out_hit);
2553 rcu_read_unlock_bh();
2554 *rp = rth;
2555 return 0;
2556 }
2557 RT_CACHE_STAT_INC(out_hlist_search);
2558 }
2559 rcu_read_unlock_bh();
2560
2561 return ip_route_output_slow(net, rp, flp);
2562 }
2563
2564 EXPORT_SYMBOL_GPL(__ip_route_output_key);
2565
2566 static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
2567 {
2568 }
2569
2570 static struct dst_ops ipv4_dst_blackhole_ops = {
2571 .family = AF_INET,
2572 .protocol = __constant_htons(ETH_P_IP),
2573 .destroy = ipv4_dst_destroy,
2574 .check = ipv4_dst_check,
2575 .update_pmtu = ipv4_rt_blackhole_update_pmtu,
2576 .entry_size = sizeof(struct rtable),
2577 .entries = ATOMIC_INIT(0),
2578 };
2579
2580
2581 static int ipv4_dst_blackhole(struct net *net, struct rtable **rp, struct flowi *flp)
2582 {
2583 struct rtable *ort = *rp;
2584 struct rtable *rt = (struct rtable *)
2585 dst_alloc(&ipv4_dst_blackhole_ops);
2586
2587 if (rt) {
2588 struct dst_entry *new = &rt->u.dst;
2589
2590 atomic_set(&new->__refcnt, 1);
2591 new->__use = 1;
2592 new->input = dst_discard;
2593 new->output = dst_discard;
2594 memcpy(new->metrics, ort->u.dst.metrics, RTAX_MAX*sizeof(u32));
2595
2596 new->dev = ort->u.dst.dev;
2597 if (new->dev)
2598 dev_hold(new->dev);
2599
2600 rt->fl = ort->fl;
2601
2602 rt->idev = ort->idev;
2603 if (rt->idev)
2604 in_dev_hold(rt->idev);
2605 rt->rt_genid = rt_genid(net);
2606 rt->rt_flags = ort->rt_flags;
2607 rt->rt_type = ort->rt_type;
2608 rt->rt_dst = ort->rt_dst;
2609 rt->rt_src = ort->rt_src;
2610 rt->rt_iif = ort->rt_iif;
2611 rt->rt_gateway = ort->rt_gateway;
2612 rt->rt_spec_dst = ort->rt_spec_dst;
2613 rt->peer = ort->peer;
2614 if (rt->peer)
2615 atomic_inc(&rt->peer->refcnt);
2616
2617 dst_free(new);
2618 }
2619
2620 dst_release(&(*rp)->u.dst);
2621 *rp = rt;
2622 return (rt ? 0 : -ENOMEM);
2623 }
2624
2625 int ip_route_output_flow(struct net *net, struct rtable **rp, struct flowi *flp,
2626 struct sock *sk, int flags)
2627 {
2628 int err;
2629
2630 if ((err = __ip_route_output_key(net, rp, flp)) != 0)
2631 return err;
2632
2633 if (flp->proto) {
2634 if (!flp->fl4_src)
2635 flp->fl4_src = (*rp)->rt_src;
2636 if (!flp->fl4_dst)
2637 flp->fl4_dst = (*rp)->rt_dst;
2638 err = __xfrm_lookup((struct dst_entry **)rp, flp, sk,
2639 flags ? XFRM_LOOKUP_WAIT : 0);
2640 if (err == -EREMOTE)
2641 err = ipv4_dst_blackhole(net, rp, flp);
2642
2643 return err;
2644 }
2645
2646 return 0;
2647 }
2648
2649 EXPORT_SYMBOL_GPL(ip_route_output_flow);
2650
2651 int ip_route_output_key(struct net *net, struct rtable **rp, struct flowi *flp)
2652 {
2653 return ip_route_output_flow(net, rp, flp, NULL, 0);
2654 }
2655
2656 static int rt_fill_info(struct sk_buff *skb, u32 pid, u32 seq, int event,
2657 int nowait, unsigned int flags)
2658 {
2659 struct rtable *rt = skb->rtable;
2660 struct rtmsg *r;
2661 struct nlmsghdr *nlh;
2662 long expires;
2663 u32 id = 0, ts = 0, tsage = 0, error;
2664
2665 nlh = nlmsg_put(skb, pid, seq, event, sizeof(*r), flags);
2666 if (nlh == NULL)
2667 return -EMSGSIZE;
2668
2669 r = nlmsg_data(nlh);
2670 r->rtm_family = AF_INET;
2671 r->rtm_dst_len = 32;
2672 r->rtm_src_len = 0;
2673 r->rtm_tos = rt->fl.fl4_tos;
2674 r->rtm_table = RT_TABLE_MAIN;
2675 NLA_PUT_U32(skb, RTA_TABLE, RT_TABLE_MAIN);
2676 r->rtm_type = rt->rt_type;
2677 r->rtm_scope = RT_SCOPE_UNIVERSE;
2678 r->rtm_protocol = RTPROT_UNSPEC;
2679 r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
2680 if (rt->rt_flags & RTCF_NOTIFY)
2681 r->rtm_flags |= RTM_F_NOTIFY;
2682
2683 NLA_PUT_BE32(skb, RTA_DST, rt->rt_dst);
2684
2685 if (rt->fl.fl4_src) {
2686 r->rtm_src_len = 32;
2687 NLA_PUT_BE32(skb, RTA_SRC, rt->fl.fl4_src);
2688 }
2689 if (rt->u.dst.dev)
2690 NLA_PUT_U32(skb, RTA_OIF, rt->u.dst.dev->ifindex);
2691 #ifdef CONFIG_NET_CLS_ROUTE
2692 if (rt->u.dst.tclassid)
2693 NLA_PUT_U32(skb, RTA_FLOW, rt->u.dst.tclassid);
2694 #endif
2695 if (rt->fl.iif)
2696 NLA_PUT_BE32(skb, RTA_PREFSRC, rt->rt_spec_dst);
2697 else if (rt->rt_src != rt->fl.fl4_src)
2698 NLA_PUT_BE32(skb, RTA_PREFSRC, rt->rt_src);
2699
2700 if (rt->rt_dst != rt->rt_gateway)
2701 NLA_PUT_BE32(skb, RTA_GATEWAY, rt->rt_gateway);
2702
2703 if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0)
2704 goto nla_put_failure;
2705
2706 error = rt->u.dst.error;
2707 expires = rt->u.dst.expires ? rt->u.dst.expires - jiffies : 0;
2708 if (rt->peer) {
2709 id = rt->peer->ip_id_count;
2710 if (rt->peer->tcp_ts_stamp) {
2711 ts = rt->peer->tcp_ts;
2712 tsage = get_seconds() - rt->peer->tcp_ts_stamp;
2713 }
2714 }
2715
2716 if (rt->fl.iif) {
2717 #ifdef CONFIG_IP_MROUTE
2718 __be32 dst = rt->rt_dst;
2719
2720 if (ipv4_is_multicast(dst) && !ipv4_is_local_multicast(dst) &&
2721 IPV4_DEVCONF_ALL(&init_net, MC_FORWARDING)) {
2722 int err = ipmr_get_route(skb, r, nowait);
2723 if (err <= 0) {
2724 if (!nowait) {
2725 if (err == 0)
2726 return 0;
2727 goto nla_put_failure;
2728 } else {
2729 if (err == -EMSGSIZE)
2730 goto nla_put_failure;
2731 error = err;
2732 }
2733 }
2734 } else
2735 #endif
2736 NLA_PUT_U32(skb, RTA_IIF, rt->fl.iif);
2737 }
2738
2739 if (rtnl_put_cacheinfo(skb, &rt->u.dst, id, ts, tsage,
2740 expires, error) < 0)
2741 goto nla_put_failure;
2742
2743 return nlmsg_end(skb, nlh);
2744
2745 nla_put_failure:
2746 nlmsg_cancel(skb, nlh);
2747 return -EMSGSIZE;
2748 }
2749
2750 static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
2751 {
2752 struct net *net = sock_net(in_skb->sk);
2753 struct rtmsg *rtm;
2754 struct nlattr *tb[RTA_MAX+1];
2755 struct rtable *rt = NULL;
2756 __be32 dst = 0;
2757 __be32 src = 0;
2758 u32 iif;
2759 int err;
2760 struct sk_buff *skb;
2761
2762 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy);
2763 if (err < 0)
2764 goto errout;
2765
2766 rtm = nlmsg_data(nlh);
2767
2768 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2769 if (skb == NULL) {
2770 err = -ENOBUFS;
2771 goto errout;
2772 }
2773
2774 /* Reserve room for dummy headers, this skb can pass
2775 through good chunk of routing engine.
2776 */
2777 skb_reset_mac_header(skb);
2778 skb_reset_network_header(skb);
2779
2780 /* Bugfix: need to give ip_route_input enough of an IP header to not gag. */
2781 ip_hdr(skb)->protocol = IPPROTO_ICMP;
2782 skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr));
2783
2784 src = tb[RTA_SRC] ? nla_get_be32(tb[RTA_SRC]) : 0;
2785 dst = tb[RTA_DST] ? nla_get_be32(tb[RTA_DST]) : 0;
2786 iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0;
2787
2788 if (iif) {
2789 struct net_device *dev;
2790
2791 dev = __dev_get_by_index(net, iif);
2792 if (dev == NULL) {
2793 err = -ENODEV;
2794 goto errout_free;
2795 }
2796
2797 skb->protocol = htons(ETH_P_IP);
2798 skb->dev = dev;
2799 local_bh_disable();
2800 err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev);
2801 local_bh_enable();
2802
2803 rt = skb->rtable;
2804 if (err == 0 && rt->u.dst.error)
2805 err = -rt->u.dst.error;
2806 } else {
2807 struct flowi fl = {
2808 .nl_u = {
2809 .ip4_u = {
2810 .daddr = dst,
2811 .saddr = src,
2812 .tos = rtm->rtm_tos,
2813 },
2814 },
2815 .oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0,
2816 };
2817 err = ip_route_output_key(net, &rt, &fl);
2818 }
2819
2820 if (err)
2821 goto errout_free;
2822
2823 skb->rtable = rt;
2824 if (rtm->rtm_flags & RTM_F_NOTIFY)
2825 rt->rt_flags |= RTCF_NOTIFY;
2826
2827 err = rt_fill_info(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq,
2828 RTM_NEWROUTE, 0, 0);
2829 if (err <= 0)
2830 goto errout_free;
2831
2832 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
2833 errout:
2834 return err;
2835
2836 errout_free:
2837 kfree_skb(skb);
2838 goto errout;
2839 }
2840
2841 int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb)
2842 {
2843 struct rtable *rt;
2844 int h, s_h;
2845 int idx, s_idx;
2846 struct net *net;
2847
2848 net = sock_net(skb->sk);
2849
2850 s_h = cb->args[0];
2851 if (s_h < 0)
2852 s_h = 0;
2853 s_idx = idx = cb->args[1];
2854 for (h = s_h; h <= rt_hash_mask; h++, s_idx = 0) {
2855 if (!rt_hash_table[h].chain)
2856 continue;
2857 rcu_read_lock_bh();
2858 for (rt = rcu_dereference(rt_hash_table[h].chain), idx = 0; rt;
2859 rt = rcu_dereference(rt->u.dst.rt_next), idx++) {
2860 if (!net_eq(dev_net(rt->u.dst.dev), net) || idx < s_idx)
2861 continue;
2862 if (rt_is_expired(rt))
2863 continue;
2864 skb->dst = dst_clone(&rt->u.dst);
2865 if (rt_fill_info(skb, NETLINK_CB(cb->skb).pid,
2866 cb->nlh->nlmsg_seq, RTM_NEWROUTE,
2867 1, NLM_F_MULTI) <= 0) {
2868 dst_release(xchg(&skb->dst, NULL));
2869 rcu_read_unlock_bh();
2870 goto done;
2871 }
2872 dst_release(xchg(&skb->dst, NULL));
2873 }
2874 rcu_read_unlock_bh();
2875 }
2876
2877 done:
2878 cb->args[0] = h;
2879 cb->args[1] = idx;
2880 return skb->len;
2881 }
2882
2883 void ip_rt_multicast_event(struct in_device *in_dev)
2884 {
2885 rt_cache_flush(dev_net(in_dev->dev), 0);
2886 }
2887
2888 #ifdef CONFIG_SYSCTL
2889 static int ipv4_sysctl_rtcache_flush(ctl_table *__ctl, int write,
2890 struct file *filp, void __user *buffer,
2891 size_t *lenp, loff_t *ppos)
2892 {
2893 if (write) {
2894 int flush_delay;
2895 ctl_table ctl;
2896 struct net *net;
2897
2898 memcpy(&ctl, __ctl, sizeof(ctl));
2899 ctl.data = &flush_delay;
2900 proc_dointvec(&ctl, write, filp, buffer, lenp, ppos);
2901
2902 net = (struct net *)__ctl->extra1;
2903 rt_cache_flush(net, flush_delay);
2904 return 0;
2905 }
2906
2907 return -EINVAL;
2908 }
2909
2910 static int ipv4_sysctl_rtcache_flush_strategy(ctl_table *table,
2911 int __user *name,
2912 int nlen,
2913 void __user *oldval,
2914 size_t __user *oldlenp,
2915 void __user *newval,
2916 size_t newlen)
2917 {
2918 int delay;
2919 struct net *net;
2920 if (newlen != sizeof(int))
2921 return -EINVAL;
2922 if (get_user(delay, (int __user *)newval))
2923 return -EFAULT;
2924 net = (struct net *)table->extra1;
2925 rt_cache_flush(net, delay);
2926 return 0;
2927 }
2928
2929 static void rt_secret_reschedule(int old)
2930 {
2931 struct net *net;
2932 int new = ip_rt_secret_interval;
2933 int diff = new - old;
2934
2935 if (!diff)
2936 return;
2937
2938 rtnl_lock();
2939 for_each_net(net) {
2940 int deleted = del_timer_sync(&net->ipv4.rt_secret_timer);
2941
2942 if (!new)
2943 continue;
2944
2945 if (deleted) {
2946 long time = net->ipv4.rt_secret_timer.expires - jiffies;
2947
2948 if (time <= 0 || (time += diff) <= 0)
2949 time = 0;
2950
2951 net->ipv4.rt_secret_timer.expires = time;
2952 } else
2953 net->ipv4.rt_secret_timer.expires = new;
2954
2955 net->ipv4.rt_secret_timer.expires += jiffies;
2956 add_timer(&net->ipv4.rt_secret_timer);
2957 }
2958 rtnl_unlock();
2959 }
2960
2961 static int ipv4_sysctl_rt_secret_interval(ctl_table *ctl, int write,
2962 struct file *filp,
2963 void __user *buffer, size_t *lenp,
2964 loff_t *ppos)
2965 {
2966 int old = ip_rt_secret_interval;
2967 int ret = proc_dointvec_jiffies(ctl, write, filp, buffer, lenp, ppos);
2968
2969 rt_secret_reschedule(old);
2970
2971 return ret;
2972 }
2973
2974 static int ipv4_sysctl_rt_secret_interval_strategy(ctl_table *table,
2975 int __user *name,
2976 int nlen,
2977 void __user *oldval,
2978 size_t __user *oldlenp,
2979 void __user *newval,
2980 size_t newlen)
2981 {
2982 int old = ip_rt_secret_interval;
2983 int ret = sysctl_jiffies(table, name, nlen, oldval, oldlenp, newval,
2984 newlen);
2985
2986 rt_secret_reschedule(old);
2987
2988 return ret;
2989 }
2990
2991 static ctl_table ipv4_route_table[] = {
2992 {
2993 .ctl_name = NET_IPV4_ROUTE_GC_THRESH,
2994 .procname = "gc_thresh",
2995 .data = &ipv4_dst_ops.gc_thresh,
2996 .maxlen = sizeof(int),
2997 .mode = 0644,
2998 .proc_handler = &proc_dointvec,
2999 },
3000 {
3001 .ctl_name = NET_IPV4_ROUTE_MAX_SIZE,
3002 .procname = "max_size",
3003 .data = &ip_rt_max_size,
3004 .maxlen = sizeof(int),
3005 .mode = 0644,
3006 .proc_handler = &proc_dointvec,
3007 },
3008 {
3009 /* Deprecated. Use gc_min_interval_ms */
3010
3011 .ctl_name = NET_IPV4_ROUTE_GC_MIN_INTERVAL,
3012 .procname = "gc_min_interval",
3013 .data = &ip_rt_gc_min_interval,
3014 .maxlen = sizeof(int),
3015 .mode = 0644,
3016 .proc_handler = &proc_dointvec_jiffies,
3017 .strategy = &sysctl_jiffies,
3018 },
3019 {
3020 .ctl_name = NET_IPV4_ROUTE_GC_MIN_INTERVAL_MS,
3021 .procname = "gc_min_interval_ms",
3022 .data = &ip_rt_gc_min_interval,
3023 .maxlen = sizeof(int),
3024 .mode = 0644,
3025 .proc_handler = &proc_dointvec_ms_jiffies,
3026 .strategy = &sysctl_ms_jiffies,
3027 },
3028 {
3029 .ctl_name = NET_IPV4_ROUTE_GC_TIMEOUT,
3030 .procname = "gc_timeout",
3031 .data = &ip_rt_gc_timeout,
3032 .maxlen = sizeof(int),
3033 .mode = 0644,
3034 .proc_handler = &proc_dointvec_jiffies,
3035 .strategy = &sysctl_jiffies,
3036 },
3037 {
3038 .ctl_name = NET_IPV4_ROUTE_GC_INTERVAL,
3039 .procname = "gc_interval",
3040 .data = &ip_rt_gc_interval,
3041 .maxlen = sizeof(int),
3042 .mode = 0644,
3043 .proc_handler = &proc_dointvec_jiffies,
3044 .strategy = &sysctl_jiffies,
3045 },
3046 {
3047 .ctl_name = NET_IPV4_ROUTE_REDIRECT_LOAD,
3048 .procname = "redirect_load",
3049 .data = &ip_rt_redirect_load,
3050 .maxlen = sizeof(int),
3051 .mode = 0644,
3052 .proc_handler = &proc_dointvec,
3053 },
3054 {
3055 .ctl_name = NET_IPV4_ROUTE_REDIRECT_NUMBER,
3056 .procname = "redirect_number",
3057 .data = &ip_rt_redirect_number,
3058 .maxlen = sizeof(int),
3059 .mode = 0644,
3060 .proc_handler = &proc_dointvec,
3061 },
3062 {
3063 .ctl_name = NET_IPV4_ROUTE_REDIRECT_SILENCE,
3064 .procname = "redirect_silence",
3065 .data = &ip_rt_redirect_silence,
3066 .maxlen = sizeof(int),
3067 .mode = 0644,
3068 .proc_handler = &proc_dointvec,
3069 },
3070 {
3071 .ctl_name = NET_IPV4_ROUTE_ERROR_COST,
3072 .procname = "error_cost",
3073 .data = &ip_rt_error_cost,
3074 .maxlen = sizeof(int),
3075 .mode = 0644,
3076 .proc_handler = &proc_dointvec,
3077 },
3078 {
3079 .ctl_name = NET_IPV4_ROUTE_ERROR_BURST,
3080 .procname = "error_burst",
3081 .data = &ip_rt_error_burst,
3082 .maxlen = sizeof(int),
3083 .mode = 0644,
3084 .proc_handler = &proc_dointvec,
3085 },
3086 {
3087 .ctl_name = NET_IPV4_ROUTE_GC_ELASTICITY,
3088 .procname = "gc_elasticity",
3089 .data = &ip_rt_gc_elasticity,
3090 .maxlen = sizeof(int),
3091 .mode = 0644,
3092 .proc_handler = &proc_dointvec,
3093 },
3094 {
3095 .ctl_name = NET_IPV4_ROUTE_MTU_EXPIRES,
3096 .procname = "mtu_expires",
3097 .data = &ip_rt_mtu_expires,
3098 .maxlen = sizeof(int),
3099 .mode = 0644,
3100 .proc_handler = &proc_dointvec_jiffies,
3101 .strategy = &sysctl_jiffies,
3102 },
3103 {
3104 .ctl_name = NET_IPV4_ROUTE_MIN_PMTU,
3105 .procname = "min_pmtu",
3106 .data = &ip_rt_min_pmtu,
3107 .maxlen = sizeof(int),
3108 .mode = 0644,
3109 .proc_handler = &proc_dointvec,
3110 },
3111 {
3112 .ctl_name = NET_IPV4_ROUTE_MIN_ADVMSS,
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 .ctl_name = NET_IPV4_ROUTE_SECRET_INTERVAL,
3121 .procname = "secret_interval",
3122 .data = &ip_rt_secret_interval,
3123 .maxlen = sizeof(int),
3124 .mode = 0644,
3125 .proc_handler = &ipv4_sysctl_rt_secret_interval,
3126 .strategy = &ipv4_sysctl_rt_secret_interval_strategy,
3127 },
3128 { .ctl_name = 0 }
3129 };
3130
3131 static struct ctl_table empty[1];
3132
3133 static struct ctl_table ipv4_skeleton[] =
3134 {
3135 { .procname = "route", .ctl_name = NET_IPV4_ROUTE,
3136 .mode = 0555, .child = ipv4_route_table},
3137 { .procname = "neigh", .ctl_name = NET_IPV4_NEIGH,
3138 .mode = 0555, .child = empty},
3139 { }
3140 };
3141
3142 static __net_initdata struct ctl_path ipv4_path[] = {
3143 { .procname = "net", .ctl_name = CTL_NET, },
3144 { .procname = "ipv4", .ctl_name = NET_IPV4, },
3145 { },
3146 };
3147
3148 static struct ctl_table ipv4_route_flush_table[] = {
3149 {
3150 .ctl_name = NET_IPV4_ROUTE_FLUSH,
3151 .procname = "flush",
3152 .maxlen = sizeof(int),
3153 .mode = 0200,
3154 .proc_handler = &ipv4_sysctl_rtcache_flush,
3155 .strategy = &ipv4_sysctl_rtcache_flush_strategy,
3156 },
3157 { .ctl_name = 0 },
3158 };
3159
3160 static __net_initdata struct ctl_path ipv4_route_path[] = {
3161 { .procname = "net", .ctl_name = CTL_NET, },
3162 { .procname = "ipv4", .ctl_name = NET_IPV4, },
3163 { .procname = "route", .ctl_name = NET_IPV4_ROUTE, },
3164 { },
3165 };
3166
3167 static __net_init int sysctl_route_net_init(struct net *net)
3168 {
3169 struct ctl_table *tbl;
3170
3171 tbl = ipv4_route_flush_table;
3172 if (net != &init_net) {
3173 tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL);
3174 if (tbl == NULL)
3175 goto err_dup;
3176 }
3177 tbl[0].extra1 = net;
3178
3179 net->ipv4.route_hdr =
3180 register_net_sysctl_table(net, ipv4_route_path, tbl);
3181 if (net->ipv4.route_hdr == NULL)
3182 goto err_reg;
3183 return 0;
3184
3185 err_reg:
3186 if (tbl != ipv4_route_flush_table)
3187 kfree(tbl);
3188 err_dup:
3189 return -ENOMEM;
3190 }
3191
3192 static __net_exit void sysctl_route_net_exit(struct net *net)
3193 {
3194 struct ctl_table *tbl;
3195
3196 tbl = net->ipv4.route_hdr->ctl_table_arg;
3197 unregister_net_sysctl_table(net->ipv4.route_hdr);
3198 BUG_ON(tbl == ipv4_route_flush_table);
3199 kfree(tbl);
3200 }
3201
3202 static __net_initdata struct pernet_operations sysctl_route_ops = {
3203 .init = sysctl_route_net_init,
3204 .exit = sysctl_route_net_exit,
3205 };
3206 #endif
3207
3208
3209 static __net_init int rt_secret_timer_init(struct net *net)
3210 {
3211 atomic_set(&net->ipv4.rt_genid,
3212 (int) ((num_physpages ^ (num_physpages>>8)) ^
3213 (jiffies ^ (jiffies >> 7))));
3214
3215 net->ipv4.rt_secret_timer.function = rt_secret_rebuild;
3216 net->ipv4.rt_secret_timer.data = (unsigned long)net;
3217 init_timer_deferrable(&net->ipv4.rt_secret_timer);
3218
3219 if (ip_rt_secret_interval) {
3220 net->ipv4.rt_secret_timer.expires =
3221 jiffies + net_random() % ip_rt_secret_interval +
3222 ip_rt_secret_interval;
3223 add_timer(&net->ipv4.rt_secret_timer);
3224 }
3225 return 0;
3226 }
3227
3228 static __net_exit void rt_secret_timer_exit(struct net *net)
3229 {
3230 del_timer_sync(&net->ipv4.rt_secret_timer);
3231 }
3232
3233 static __net_initdata struct pernet_operations rt_secret_timer_ops = {
3234 .init = rt_secret_timer_init,
3235 .exit = rt_secret_timer_exit,
3236 };
3237
3238
3239 #ifdef CONFIG_NET_CLS_ROUTE
3240 struct ip_rt_acct *ip_rt_acct __read_mostly;
3241 #endif /* CONFIG_NET_CLS_ROUTE */
3242
3243 static __initdata unsigned long rhash_entries;
3244 static int __init set_rhash_entries(char *str)
3245 {
3246 if (!str)
3247 return 0;
3248 rhash_entries = simple_strtoul(str, &str, 0);
3249 return 1;
3250 }
3251 __setup("rhash_entries=", set_rhash_entries);
3252
3253 int __init ip_rt_init(void)
3254 {
3255 int rc = 0;
3256
3257 #ifdef CONFIG_NET_CLS_ROUTE
3258 ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct));
3259 if (!ip_rt_acct)
3260 panic("IP: failed to allocate ip_rt_acct\n");
3261 #endif
3262
3263 ipv4_dst_ops.kmem_cachep =
3264 kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0,
3265 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
3266
3267 ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep;
3268
3269 rt_hash_table = (struct rt_hash_bucket *)
3270 alloc_large_system_hash("IP route cache",
3271 sizeof(struct rt_hash_bucket),
3272 rhash_entries,
3273 (num_physpages >= 128 * 1024) ?
3274 15 : 17,
3275 0,
3276 &rt_hash_log,
3277 &rt_hash_mask,
3278 0);
3279 memset(rt_hash_table, 0, (rt_hash_mask + 1) * sizeof(struct rt_hash_bucket));
3280 rt_hash_lock_init();
3281
3282 ipv4_dst_ops.gc_thresh = (rt_hash_mask + 1);
3283 ip_rt_max_size = (rt_hash_mask + 1) * 16;
3284
3285 devinet_init();
3286 ip_fib_init();
3287
3288 /* All the timers, started at system startup tend
3289 to synchronize. Perturb it a bit.
3290 */
3291 schedule_delayed_work(&expires_work,
3292 net_random() % ip_rt_gc_interval + ip_rt_gc_interval);
3293
3294 if (register_pernet_subsys(&rt_secret_timer_ops))
3295 printk(KERN_ERR "Unable to setup rt_secret_timer\n");
3296
3297 if (ip_rt_proc_init())
3298 printk(KERN_ERR "Unable to create route proc files\n");
3299 #ifdef CONFIG_XFRM
3300 xfrm_init();
3301 xfrm4_init();
3302 #endif
3303 rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL);
3304
3305 #ifdef CONFIG_SYSCTL
3306 register_pernet_subsys(&sysctl_route_ops);
3307 #endif
3308 return rc;
3309 }
3310
3311 #ifdef CONFIG_SYSCTL
3312 /*
3313 * We really need to sanitize the damn ipv4 init order, then all
3314 * this nonsense will go away.
3315 */
3316 void __init ip_static_sysctl_init(void)
3317 {
3318 register_sysctl_paths(ipv4_path, ipv4_skeleton);
3319 }
3320 #endif
3321
3322 EXPORT_SYMBOL(__ip_select_ident);
3323 EXPORT_SYMBOL(ip_route_input);
3324 EXPORT_SYMBOL(ip_route_output_key);
Support for the Chinese Samsung S3C2440 based development boards