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1da177e4 LT |
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 | * Version: $Id: route.c,v 1.103 2002/01/12 07:44:09 davem Exp $ | |
9 | * | |
10 | * Authors: Ross Biro, <bir7@leland.Stanford.Edu> | |
11 | * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> | |
12 | * Alan Cox, <gw4pts@gw4pts.ampr.org> | |
13 | * Linus Torvalds, <Linus.Torvalds@helsinki.fi> | |
14 | * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> | |
15 | * | |
16 | * Fixes: | |
17 | * Alan Cox : Verify area fixes. | |
18 | * Alan Cox : cli() protects routing changes | |
19 | * Rui Oliveira : ICMP routing table updates | |
20 | * (rco@di.uminho.pt) Routing table insertion and update | |
21 | * Linus Torvalds : Rewrote bits to be sensible | |
22 | * Alan Cox : Added BSD route gw semantics | |
23 | * Alan Cox : Super /proc >4K | |
24 | * Alan Cox : MTU in route table | |
25 | * Alan Cox : MSS actually. Also added the window | |
26 | * clamper. | |
27 | * Sam Lantinga : Fixed route matching in rt_del() | |
28 | * Alan Cox : Routing cache support. | |
29 | * Alan Cox : Removed compatibility cruft. | |
30 | * Alan Cox : RTF_REJECT support. | |
31 | * Alan Cox : TCP irtt support. | |
32 | * Jonathan Naylor : Added Metric support. | |
33 | * Miquel van Smoorenburg : BSD API fixes. | |
34 | * Miquel van Smoorenburg : Metrics. | |
35 | * Alan Cox : Use __u32 properly | |
36 | * Alan Cox : Aligned routing errors more closely with BSD | |
37 | * our system is still very different. | |
38 | * Alan Cox : Faster /proc handling | |
39 | * Alexey Kuznetsov : Massive rework to support tree based routing, | |
40 | * routing caches and better behaviour. | |
41 | * | |
42 | * Olaf Erb : irtt wasn't being copied right. | |
43 | * Bjorn Ekwall : Kerneld route support. | |
44 | * Alan Cox : Multicast fixed (I hope) | |
45 | * Pavel Krauz : Limited broadcast fixed | |
46 | * Mike McLagan : Routing by source | |
47 | * Alexey Kuznetsov : End of old history. Split to fib.c and | |
48 | * route.c and rewritten from scratch. | |
49 | * Andi Kleen : Load-limit warning messages. | |
50 | * Vitaly E. Lavrov : Transparent proxy revived after year coma. | |
51 | * Vitaly E. Lavrov : Race condition in ip_route_input_slow. | |
52 | * Tobias Ringstrom : Uninitialized res.type in ip_route_output_slow. | |
53 | * Vladimir V. Ivanov : IP rule info (flowid) is really useful. | |
54 | * Marc Boucher : routing by fwmark | |
55 | * Robert Olsson : Added rt_cache statistics | |
56 | * Arnaldo C. Melo : Convert proc stuff to seq_file | |
57 | * | |
58 | * This program is free software; you can redistribute it and/or | |
59 | * modify it under the terms of the GNU General Public License | |
60 | * as published by the Free Software Foundation; either version | |
61 | * 2 of the License, or (at your option) any later version. | |
62 | */ | |
63 | ||
64 | #include <linux/config.h> | |
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/sched.h> | |
72 | #include <linux/mm.h> | |
73 | #include <linux/string.h> | |
74 | #include <linux/socket.h> | |
75 | #include <linux/sockios.h> | |
76 | #include <linux/errno.h> | |
77 | #include <linux/in.h> | |
78 | #include <linux/inet.h> | |
79 | #include <linux/netdevice.h> | |
80 | #include <linux/proc_fs.h> | |
81 | #include <linux/init.h> | |
82 | #include <linux/skbuff.h> | |
83 | #include <linux/rtnetlink.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/protocol.h> | |
94 | #include <net/ip.h> | |
95 | #include <net/route.h> | |
96 | #include <net/inetpeer.h> | |
97 | #include <net/sock.h> | |
98 | #include <net/ip_fib.h> | |
99 | #include <net/arp.h> | |
100 | #include <net/tcp.h> | |
101 | #include <net/icmp.h> | |
102 | #include <net/xfrm.h> | |
103 | #include <net/ip_mp_alg.h> | |
104 | #ifdef CONFIG_SYSCTL | |
105 | #include <linux/sysctl.h> | |
106 | #endif | |
107 | ||
108 | #define RT_FL_TOS(oldflp) \ | |
109 | ((u32)(oldflp->fl4_tos & (IPTOS_RT_MASK | RTO_ONLINK))) | |
110 | ||
111 | #define IP_MAX_MTU 0xFFF0 | |
112 | ||
113 | #define RT_GC_TIMEOUT (300*HZ) | |
114 | ||
115 | static int ip_rt_min_delay = 2 * HZ; | |
116 | static int ip_rt_max_delay = 10 * HZ; | |
117 | static int ip_rt_max_size; | |
118 | static int ip_rt_gc_timeout = RT_GC_TIMEOUT; | |
119 | static int ip_rt_gc_interval = 60 * HZ; | |
120 | static int ip_rt_gc_min_interval = HZ / 2; | |
121 | static int ip_rt_redirect_number = 9; | |
122 | static int ip_rt_redirect_load = HZ / 50; | |
123 | static int ip_rt_redirect_silence = ((HZ / 50) << (9 + 1)); | |
124 | static int ip_rt_error_cost = HZ; | |
125 | static int ip_rt_error_burst = 5 * HZ; | |
126 | static int ip_rt_gc_elasticity = 8; | |
127 | static int ip_rt_mtu_expires = 10 * 60 * HZ; | |
128 | static int ip_rt_min_pmtu = 512 + 20 + 20; | |
129 | static int ip_rt_min_advmss = 256; | |
130 | static int ip_rt_secret_interval = 10 * 60 * HZ; | |
131 | static unsigned long rt_deadline; | |
132 | ||
133 | #define RTprint(a...) printk(KERN_DEBUG a) | |
134 | ||
135 | static struct timer_list rt_flush_timer; | |
136 | static struct timer_list rt_periodic_timer; | |
137 | static struct timer_list rt_secret_timer; | |
138 | ||
139 | /* | |
140 | * Interface to generic destination cache. | |
141 | */ | |
142 | ||
143 | static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie); | |
144 | static void ipv4_dst_destroy(struct dst_entry *dst); | |
145 | static void ipv4_dst_ifdown(struct dst_entry *dst, | |
146 | struct net_device *dev, int how); | |
147 | static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst); | |
148 | static void ipv4_link_failure(struct sk_buff *skb); | |
149 | static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu); | |
150 | static int rt_garbage_collect(void); | |
151 | ||
152 | ||
153 | static struct dst_ops ipv4_dst_ops = { | |
154 | .family = AF_INET, | |
155 | .protocol = __constant_htons(ETH_P_IP), | |
156 | .gc = rt_garbage_collect, | |
157 | .check = ipv4_dst_check, | |
158 | .destroy = ipv4_dst_destroy, | |
159 | .ifdown = ipv4_dst_ifdown, | |
160 | .negative_advice = ipv4_negative_advice, | |
161 | .link_failure = ipv4_link_failure, | |
162 | .update_pmtu = ip_rt_update_pmtu, | |
163 | .entry_size = sizeof(struct rtable), | |
164 | }; | |
165 | ||
166 | #define ECN_OR_COST(class) TC_PRIO_##class | |
167 | ||
168 | __u8 ip_tos2prio[16] = { | |
169 | TC_PRIO_BESTEFFORT, | |
170 | ECN_OR_COST(FILLER), | |
171 | TC_PRIO_BESTEFFORT, | |
172 | ECN_OR_COST(BESTEFFORT), | |
173 | TC_PRIO_BULK, | |
174 | ECN_OR_COST(BULK), | |
175 | TC_PRIO_BULK, | |
176 | ECN_OR_COST(BULK), | |
177 | TC_PRIO_INTERACTIVE, | |
178 | ECN_OR_COST(INTERACTIVE), | |
179 | TC_PRIO_INTERACTIVE, | |
180 | ECN_OR_COST(INTERACTIVE), | |
181 | TC_PRIO_INTERACTIVE_BULK, | |
182 | ECN_OR_COST(INTERACTIVE_BULK), | |
183 | TC_PRIO_INTERACTIVE_BULK, | |
184 | ECN_OR_COST(INTERACTIVE_BULK) | |
185 | }; | |
186 | ||
187 | ||
188 | /* | |
189 | * Route cache. | |
190 | */ | |
191 | ||
192 | /* The locking scheme is rather straight forward: | |
193 | * | |
194 | * 1) Read-Copy Update protects the buckets of the central route hash. | |
195 | * 2) Only writers remove entries, and they hold the lock | |
196 | * as they look at rtable reference counts. | |
197 | * 3) Only readers acquire references to rtable entries, | |
198 | * they do so with atomic increments and with the | |
199 | * lock held. | |
200 | */ | |
201 | ||
202 | struct rt_hash_bucket { | |
203 | struct rtable *chain; | |
204 | spinlock_t lock; | |
205 | } __attribute__((__aligned__(8))); | |
206 | ||
207 | static struct rt_hash_bucket *rt_hash_table; | |
208 | static unsigned rt_hash_mask; | |
209 | static int rt_hash_log; | |
210 | static unsigned int rt_hash_rnd; | |
211 | ||
212 | struct rt_cache_stat *rt_cache_stat; | |
213 | ||
214 | static int rt_intern_hash(unsigned hash, struct rtable *rth, | |
215 | struct rtable **res); | |
216 | ||
217 | static unsigned int rt_hash_code(u32 daddr, u32 saddr, u8 tos) | |
218 | { | |
219 | return (jhash_3words(daddr, saddr, (u32) tos, rt_hash_rnd) | |
220 | & rt_hash_mask); | |
221 | } | |
222 | ||
223 | #ifdef CONFIG_PROC_FS | |
224 | struct rt_cache_iter_state { | |
225 | int bucket; | |
226 | }; | |
227 | ||
228 | static struct rtable *rt_cache_get_first(struct seq_file *seq) | |
229 | { | |
230 | struct rtable *r = NULL; | |
231 | struct rt_cache_iter_state *st = seq->private; | |
232 | ||
233 | for (st->bucket = rt_hash_mask; st->bucket >= 0; --st->bucket) { | |
234 | rcu_read_lock_bh(); | |
235 | r = rt_hash_table[st->bucket].chain; | |
236 | if (r) | |
237 | break; | |
238 | rcu_read_unlock_bh(); | |
239 | } | |
240 | return r; | |
241 | } | |
242 | ||
243 | static struct rtable *rt_cache_get_next(struct seq_file *seq, struct rtable *r) | |
244 | { | |
245 | struct rt_cache_iter_state *st = rcu_dereference(seq->private); | |
246 | ||
247 | r = r->u.rt_next; | |
248 | while (!r) { | |
249 | rcu_read_unlock_bh(); | |
250 | if (--st->bucket < 0) | |
251 | break; | |
252 | rcu_read_lock_bh(); | |
253 | r = rt_hash_table[st->bucket].chain; | |
254 | } | |
255 | return r; | |
256 | } | |
257 | ||
258 | static struct rtable *rt_cache_get_idx(struct seq_file *seq, loff_t pos) | |
259 | { | |
260 | struct rtable *r = rt_cache_get_first(seq); | |
261 | ||
262 | if (r) | |
263 | while (pos && (r = rt_cache_get_next(seq, r))) | |
264 | --pos; | |
265 | return pos ? NULL : r; | |
266 | } | |
267 | ||
268 | static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos) | |
269 | { | |
270 | return *pos ? rt_cache_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; | |
271 | } | |
272 | ||
273 | static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
274 | { | |
275 | struct rtable *r = NULL; | |
276 | ||
277 | if (v == SEQ_START_TOKEN) | |
278 | r = rt_cache_get_first(seq); | |
279 | else | |
280 | r = rt_cache_get_next(seq, v); | |
281 | ++*pos; | |
282 | return r; | |
283 | } | |
284 | ||
285 | static void rt_cache_seq_stop(struct seq_file *seq, void *v) | |
286 | { | |
287 | if (v && v != SEQ_START_TOKEN) | |
288 | rcu_read_unlock_bh(); | |
289 | } | |
290 | ||
291 | static int rt_cache_seq_show(struct seq_file *seq, void *v) | |
292 | { | |
293 | if (v == SEQ_START_TOKEN) | |
294 | seq_printf(seq, "%-127s\n", | |
295 | "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t" | |
296 | "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t" | |
297 | "HHUptod\tSpecDst"); | |
298 | else { | |
299 | struct rtable *r = v; | |
300 | char temp[256]; | |
301 | ||
302 | sprintf(temp, "%s\t%08lX\t%08lX\t%8X\t%d\t%u\t%d\t" | |
303 | "%08lX\t%d\t%u\t%u\t%02X\t%d\t%1d\t%08X", | |
304 | r->u.dst.dev ? r->u.dst.dev->name : "*", | |
305 | (unsigned long)r->rt_dst, (unsigned long)r->rt_gateway, | |
306 | r->rt_flags, atomic_read(&r->u.dst.__refcnt), | |
307 | r->u.dst.__use, 0, (unsigned long)r->rt_src, | |
308 | (dst_metric(&r->u.dst, RTAX_ADVMSS) ? | |
309 | (int)dst_metric(&r->u.dst, RTAX_ADVMSS) + 40 : 0), | |
310 | dst_metric(&r->u.dst, RTAX_WINDOW), | |
311 | (int)((dst_metric(&r->u.dst, RTAX_RTT) >> 3) + | |
312 | dst_metric(&r->u.dst, RTAX_RTTVAR)), | |
313 | r->fl.fl4_tos, | |
314 | r->u.dst.hh ? atomic_read(&r->u.dst.hh->hh_refcnt) : -1, | |
315 | r->u.dst.hh ? (r->u.dst.hh->hh_output == | |
316 | dev_queue_xmit) : 0, | |
317 | r->rt_spec_dst); | |
318 | seq_printf(seq, "%-127s\n", temp); | |
319 | } | |
320 | return 0; | |
321 | } | |
322 | ||
323 | static struct seq_operations rt_cache_seq_ops = { | |
324 | .start = rt_cache_seq_start, | |
325 | .next = rt_cache_seq_next, | |
326 | .stop = rt_cache_seq_stop, | |
327 | .show = rt_cache_seq_show, | |
328 | }; | |
329 | ||
330 | static int rt_cache_seq_open(struct inode *inode, struct file *file) | |
331 | { | |
332 | struct seq_file *seq; | |
333 | int rc = -ENOMEM; | |
334 | struct rt_cache_iter_state *s = kmalloc(sizeof(*s), GFP_KERNEL); | |
335 | ||
336 | if (!s) | |
337 | goto out; | |
338 | rc = seq_open(file, &rt_cache_seq_ops); | |
339 | if (rc) | |
340 | goto out_kfree; | |
341 | seq = file->private_data; | |
342 | seq->private = s; | |
343 | memset(s, 0, sizeof(*s)); | |
344 | out: | |
345 | return rc; | |
346 | out_kfree: | |
347 | kfree(s); | |
348 | goto out; | |
349 | } | |
350 | ||
351 | static struct file_operations rt_cache_seq_fops = { | |
352 | .owner = THIS_MODULE, | |
353 | .open = rt_cache_seq_open, | |
354 | .read = seq_read, | |
355 | .llseek = seq_lseek, | |
356 | .release = seq_release_private, | |
357 | }; | |
358 | ||
359 | ||
360 | static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos) | |
361 | { | |
362 | int cpu; | |
363 | ||
364 | if (*pos == 0) | |
365 | return SEQ_START_TOKEN; | |
366 | ||
367 | for (cpu = *pos-1; cpu < NR_CPUS; ++cpu) { | |
368 | if (!cpu_possible(cpu)) | |
369 | continue; | |
370 | *pos = cpu+1; | |
371 | return per_cpu_ptr(rt_cache_stat, cpu); | |
372 | } | |
373 | return NULL; | |
374 | } | |
375 | ||
376 | static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
377 | { | |
378 | int cpu; | |
379 | ||
380 | for (cpu = *pos; cpu < NR_CPUS; ++cpu) { | |
381 | if (!cpu_possible(cpu)) | |
382 | continue; | |
383 | *pos = cpu+1; | |
384 | return per_cpu_ptr(rt_cache_stat, cpu); | |
385 | } | |
386 | return NULL; | |
387 | ||
388 | } | |
389 | ||
390 | static void rt_cpu_seq_stop(struct seq_file *seq, void *v) | |
391 | { | |
392 | ||
393 | } | |
394 | ||
395 | static int rt_cpu_seq_show(struct seq_file *seq, void *v) | |
396 | { | |
397 | struct rt_cache_stat *st = v; | |
398 | ||
399 | if (v == SEQ_START_TOKEN) { | |
400 | seq_printf(seq, "entries in_hit in_slow_tot 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"); | |
401 | return 0; | |
402 | } | |
403 | ||
404 | seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x " | |
405 | " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n", | |
406 | atomic_read(&ipv4_dst_ops.entries), | |
407 | st->in_hit, | |
408 | st->in_slow_tot, | |
409 | st->in_slow_mc, | |
410 | st->in_no_route, | |
411 | st->in_brd, | |
412 | st->in_martian_dst, | |
413 | st->in_martian_src, | |
414 | ||
415 | st->out_hit, | |
416 | st->out_slow_tot, | |
417 | st->out_slow_mc, | |
418 | ||
419 | st->gc_total, | |
420 | st->gc_ignored, | |
421 | st->gc_goal_miss, | |
422 | st->gc_dst_overflow, | |
423 | st->in_hlist_search, | |
424 | st->out_hlist_search | |
425 | ); | |
426 | return 0; | |
427 | } | |
428 | ||
429 | static struct seq_operations rt_cpu_seq_ops = { | |
430 | .start = rt_cpu_seq_start, | |
431 | .next = rt_cpu_seq_next, | |
432 | .stop = rt_cpu_seq_stop, | |
433 | .show = rt_cpu_seq_show, | |
434 | }; | |
435 | ||
436 | ||
437 | static int rt_cpu_seq_open(struct inode *inode, struct file *file) | |
438 | { | |
439 | return seq_open(file, &rt_cpu_seq_ops); | |
440 | } | |
441 | ||
442 | static struct file_operations rt_cpu_seq_fops = { | |
443 | .owner = THIS_MODULE, | |
444 | .open = rt_cpu_seq_open, | |
445 | .read = seq_read, | |
446 | .llseek = seq_lseek, | |
447 | .release = seq_release, | |
448 | }; | |
449 | ||
450 | #endif /* CONFIG_PROC_FS */ | |
451 | ||
452 | static __inline__ void rt_free(struct rtable *rt) | |
453 | { | |
454 | multipath_remove(rt); | |
455 | call_rcu_bh(&rt->u.dst.rcu_head, dst_rcu_free); | |
456 | } | |
457 | ||
458 | static __inline__ void rt_drop(struct rtable *rt) | |
459 | { | |
460 | multipath_remove(rt); | |
461 | ip_rt_put(rt); | |
462 | call_rcu_bh(&rt->u.dst.rcu_head, dst_rcu_free); | |
463 | } | |
464 | ||
465 | static __inline__ int rt_fast_clean(struct rtable *rth) | |
466 | { | |
467 | /* Kill broadcast/multicast entries very aggresively, if they | |
468 | collide in hash table with more useful entries */ | |
469 | return (rth->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) && | |
470 | rth->fl.iif && rth->u.rt_next; | |
471 | } | |
472 | ||
473 | static __inline__ int rt_valuable(struct rtable *rth) | |
474 | { | |
475 | return (rth->rt_flags & (RTCF_REDIRECTED | RTCF_NOTIFY)) || | |
476 | rth->u.dst.expires; | |
477 | } | |
478 | ||
479 | static int rt_may_expire(struct rtable *rth, unsigned long tmo1, unsigned long tmo2) | |
480 | { | |
481 | unsigned long age; | |
482 | int ret = 0; | |
483 | ||
484 | if (atomic_read(&rth->u.dst.__refcnt)) | |
485 | goto out; | |
486 | ||
487 | ret = 1; | |
488 | if (rth->u.dst.expires && | |
489 | time_after_eq(jiffies, rth->u.dst.expires)) | |
490 | goto out; | |
491 | ||
492 | age = jiffies - rth->u.dst.lastuse; | |
493 | ret = 0; | |
494 | if ((age <= tmo1 && !rt_fast_clean(rth)) || | |
495 | (age <= tmo2 && rt_valuable(rth))) | |
496 | goto out; | |
497 | ret = 1; | |
498 | out: return ret; | |
499 | } | |
500 | ||
501 | /* Bits of score are: | |
502 | * 31: very valuable | |
503 | * 30: not quite useless | |
504 | * 29..0: usage counter | |
505 | */ | |
506 | static inline u32 rt_score(struct rtable *rt) | |
507 | { | |
508 | u32 score = jiffies - rt->u.dst.lastuse; | |
509 | ||
510 | score = ~score & ~(3<<30); | |
511 | ||
512 | if (rt_valuable(rt)) | |
513 | score |= (1<<31); | |
514 | ||
515 | if (!rt->fl.iif || | |
516 | !(rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST|RTCF_LOCAL))) | |
517 | score |= (1<<30); | |
518 | ||
519 | return score; | |
520 | } | |
521 | ||
522 | static inline int compare_keys(struct flowi *fl1, struct flowi *fl2) | |
523 | { | |
524 | return memcmp(&fl1->nl_u.ip4_u, &fl2->nl_u.ip4_u, sizeof(fl1->nl_u.ip4_u)) == 0 && | |
525 | fl1->oif == fl2->oif && | |
526 | fl1->iif == fl2->iif; | |
527 | } | |
528 | ||
529 | #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED | |
530 | static struct rtable **rt_remove_balanced_route(struct rtable **chain_head, | |
531 | struct rtable *expentry, | |
532 | int *removed_count) | |
533 | { | |
534 | int passedexpired = 0; | |
535 | struct rtable **nextstep = NULL; | |
536 | struct rtable **rthp = chain_head; | |
537 | struct rtable *rth; | |
538 | ||
539 | if (removed_count) | |
540 | *removed_count = 0; | |
541 | ||
542 | while ((rth = *rthp) != NULL) { | |
543 | if (rth == expentry) | |
544 | passedexpired = 1; | |
545 | ||
546 | if (((*rthp)->u.dst.flags & DST_BALANCED) != 0 && | |
547 | compare_keys(&(*rthp)->fl, &expentry->fl)) { | |
548 | if (*rthp == expentry) { | |
549 | *rthp = rth->u.rt_next; | |
550 | continue; | |
551 | } else { | |
552 | *rthp = rth->u.rt_next; | |
553 | rt_free(rth); | |
554 | if (removed_count) | |
555 | ++(*removed_count); | |
556 | } | |
557 | } else { | |
558 | if (!((*rthp)->u.dst.flags & DST_BALANCED) && | |
559 | passedexpired && !nextstep) | |
560 | nextstep = &rth->u.rt_next; | |
561 | ||
562 | rthp = &rth->u.rt_next; | |
563 | } | |
564 | } | |
565 | ||
566 | rt_free(expentry); | |
567 | if (removed_count) | |
568 | ++(*removed_count); | |
569 | ||
570 | return nextstep; | |
571 | } | |
572 | #endif /* CONFIG_IP_ROUTE_MULTIPATH_CACHED */ | |
573 | ||
574 | ||
575 | /* This runs via a timer and thus is always in BH context. */ | |
576 | static void rt_check_expire(unsigned long dummy) | |
577 | { | |
578 | static int rover; | |
579 | int i = rover, t; | |
580 | struct rtable *rth, **rthp; | |
581 | unsigned long now = jiffies; | |
582 | ||
583 | for (t = ip_rt_gc_interval << rt_hash_log; t >= 0; | |
584 | t -= ip_rt_gc_timeout) { | |
585 | unsigned long tmo = ip_rt_gc_timeout; | |
586 | ||
587 | i = (i + 1) & rt_hash_mask; | |
588 | rthp = &rt_hash_table[i].chain; | |
589 | ||
590 | spin_lock(&rt_hash_table[i].lock); | |
591 | while ((rth = *rthp) != NULL) { | |
592 | if (rth->u.dst.expires) { | |
593 | /* Entry is expired even if it is in use */ | |
594 | if (time_before_eq(now, rth->u.dst.expires)) { | |
595 | tmo >>= 1; | |
596 | rthp = &rth->u.rt_next; | |
597 | continue; | |
598 | } | |
599 | } else if (!rt_may_expire(rth, tmo, ip_rt_gc_timeout)) { | |
600 | tmo >>= 1; | |
601 | rthp = &rth->u.rt_next; | |
602 | continue; | |
603 | } | |
604 | ||
605 | /* Cleanup aged off entries. */ | |
606 | #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED | |
607 | /* remove all related balanced entries if necessary */ | |
608 | if (rth->u.dst.flags & DST_BALANCED) { | |
609 | rthp = rt_remove_balanced_route( | |
610 | &rt_hash_table[i].chain, | |
611 | rth, NULL); | |
612 | if (!rthp) | |
613 | break; | |
614 | } else { | |
615 | *rthp = rth->u.rt_next; | |
616 | rt_free(rth); | |
617 | } | |
618 | #else /* CONFIG_IP_ROUTE_MULTIPATH_CACHED */ | |
619 | *rthp = rth->u.rt_next; | |
620 | rt_free(rth); | |
621 | #endif /* CONFIG_IP_ROUTE_MULTIPATH_CACHED */ | |
622 | } | |
623 | spin_unlock(&rt_hash_table[i].lock); | |
624 | ||
625 | /* Fallback loop breaker. */ | |
626 | if (time_after(jiffies, now)) | |
627 | break; | |
628 | } | |
629 | rover = i; | |
630 | mod_timer(&rt_periodic_timer, now + ip_rt_gc_interval); | |
631 | } | |
632 | ||
633 | /* This can run from both BH and non-BH contexts, the latter | |
634 | * in the case of a forced flush event. | |
635 | */ | |
636 | static void rt_run_flush(unsigned long dummy) | |
637 | { | |
638 | int i; | |
639 | struct rtable *rth, *next; | |
640 | ||
641 | rt_deadline = 0; | |
642 | ||
643 | get_random_bytes(&rt_hash_rnd, 4); | |
644 | ||
645 | for (i = rt_hash_mask; i >= 0; i--) { | |
646 | spin_lock_bh(&rt_hash_table[i].lock); | |
647 | rth = rt_hash_table[i].chain; | |
648 | if (rth) | |
649 | rt_hash_table[i].chain = NULL; | |
650 | spin_unlock_bh(&rt_hash_table[i].lock); | |
651 | ||
652 | for (; rth; rth = next) { | |
653 | next = rth->u.rt_next; | |
654 | rt_free(rth); | |
655 | } | |
656 | } | |
657 | } | |
658 | ||
659 | static DEFINE_SPINLOCK(rt_flush_lock); | |
660 | ||
661 | void rt_cache_flush(int delay) | |
662 | { | |
663 | unsigned long now = jiffies; | |
664 | int user_mode = !in_softirq(); | |
665 | ||
666 | if (delay < 0) | |
667 | delay = ip_rt_min_delay; | |
668 | ||
669 | /* flush existing multipath state*/ | |
670 | multipath_flush(); | |
671 | ||
672 | spin_lock_bh(&rt_flush_lock); | |
673 | ||
674 | if (del_timer(&rt_flush_timer) && delay > 0 && rt_deadline) { | |
675 | long tmo = (long)(rt_deadline - now); | |
676 | ||
677 | /* If flush timer is already running | |
678 | and flush request is not immediate (delay > 0): | |
679 | ||
680 | if deadline is not achieved, prolongate timer to "delay", | |
681 | otherwise fire it at deadline time. | |
682 | */ | |
683 | ||
684 | if (user_mode && tmo < ip_rt_max_delay-ip_rt_min_delay) | |
685 | tmo = 0; | |
686 | ||
687 | if (delay > tmo) | |
688 | delay = tmo; | |
689 | } | |
690 | ||
691 | if (delay <= 0) { | |
692 | spin_unlock_bh(&rt_flush_lock); | |
693 | rt_run_flush(0); | |
694 | return; | |
695 | } | |
696 | ||
697 | if (rt_deadline == 0) | |
698 | rt_deadline = now + ip_rt_max_delay; | |
699 | ||
700 | mod_timer(&rt_flush_timer, now+delay); | |
701 | spin_unlock_bh(&rt_flush_lock); | |
702 | } | |
703 | ||
704 | static void rt_secret_rebuild(unsigned long dummy) | |
705 | { | |
706 | unsigned long now = jiffies; | |
707 | ||
708 | rt_cache_flush(0); | |
709 | mod_timer(&rt_secret_timer, now + ip_rt_secret_interval); | |
710 | } | |
711 | ||
712 | /* | |
713 | Short description of GC goals. | |
714 | ||
715 | We want to build algorithm, which will keep routing cache | |
716 | at some equilibrium point, when number of aged off entries | |
717 | is kept approximately equal to newly generated ones. | |
718 | ||
719 | Current expiration strength is variable "expire". | |
720 | We try to adjust it dynamically, so that if networking | |
721 | is idle expires is large enough to keep enough of warm entries, | |
722 | and when load increases it reduces to limit cache size. | |
723 | */ | |
724 | ||
725 | static int rt_garbage_collect(void) | |
726 | { | |
727 | static unsigned long expire = RT_GC_TIMEOUT; | |
728 | static unsigned long last_gc; | |
729 | static int rover; | |
730 | static int equilibrium; | |
731 | struct rtable *rth, **rthp; | |
732 | unsigned long now = jiffies; | |
733 | int goal; | |
734 | ||
735 | /* | |
736 | * Garbage collection is pretty expensive, | |
737 | * do not make it too frequently. | |
738 | */ | |
739 | ||
740 | RT_CACHE_STAT_INC(gc_total); | |
741 | ||
742 | if (now - last_gc < ip_rt_gc_min_interval && | |
743 | atomic_read(&ipv4_dst_ops.entries) < ip_rt_max_size) { | |
744 | RT_CACHE_STAT_INC(gc_ignored); | |
745 | goto out; | |
746 | } | |
747 | ||
748 | /* Calculate number of entries, which we want to expire now. */ | |
749 | goal = atomic_read(&ipv4_dst_ops.entries) - | |
750 | (ip_rt_gc_elasticity << rt_hash_log); | |
751 | if (goal <= 0) { | |
752 | if (equilibrium < ipv4_dst_ops.gc_thresh) | |
753 | equilibrium = ipv4_dst_ops.gc_thresh; | |
754 | goal = atomic_read(&ipv4_dst_ops.entries) - equilibrium; | |
755 | if (goal > 0) { | |
756 | equilibrium += min_t(unsigned int, goal / 2, rt_hash_mask + 1); | |
757 | goal = atomic_read(&ipv4_dst_ops.entries) - equilibrium; | |
758 | } | |
759 | } else { | |
760 | /* We are in dangerous area. Try to reduce cache really | |
761 | * aggressively. | |
762 | */ | |
763 | goal = max_t(unsigned int, goal / 2, rt_hash_mask + 1); | |
764 | equilibrium = atomic_read(&ipv4_dst_ops.entries) - goal; | |
765 | } | |
766 | ||
767 | if (now - last_gc >= ip_rt_gc_min_interval) | |
768 | last_gc = now; | |
769 | ||
770 | if (goal <= 0) { | |
771 | equilibrium += goal; | |
772 | goto work_done; | |
773 | } | |
774 | ||
775 | do { | |
776 | int i, k; | |
777 | ||
778 | for (i = rt_hash_mask, k = rover; i >= 0; i--) { | |
779 | unsigned long tmo = expire; | |
780 | ||
781 | k = (k + 1) & rt_hash_mask; | |
782 | rthp = &rt_hash_table[k].chain; | |
783 | spin_lock_bh(&rt_hash_table[k].lock); | |
784 | while ((rth = *rthp) != NULL) { | |
785 | if (!rt_may_expire(rth, tmo, expire)) { | |
786 | tmo >>= 1; | |
787 | rthp = &rth->u.rt_next; | |
788 | continue; | |
789 | } | |
790 | #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED | |
791 | /* remove all related balanced entries | |
792 | * if necessary | |
793 | */ | |
794 | if (rth->u.dst.flags & DST_BALANCED) { | |
795 | int r; | |
796 | ||
797 | rthp = rt_remove_balanced_route( | |
798 | &rt_hash_table[i].chain, | |
799 | rth, | |
800 | &r); | |
801 | goal -= r; | |
802 | if (!rthp) | |
803 | break; | |
804 | } else { | |
805 | *rthp = rth->u.rt_next; | |
806 | rt_free(rth); | |
807 | goal--; | |
808 | } | |
809 | #else /* CONFIG_IP_ROUTE_MULTIPATH_CACHED */ | |
810 | *rthp = rth->u.rt_next; | |
811 | rt_free(rth); | |
812 | goal--; | |
813 | #endif /* CONFIG_IP_ROUTE_MULTIPATH_CACHED */ | |
814 | } | |
815 | spin_unlock_bh(&rt_hash_table[k].lock); | |
816 | if (goal <= 0) | |
817 | break; | |
818 | } | |
819 | rover = k; | |
820 | ||
821 | if (goal <= 0) | |
822 | goto work_done; | |
823 | ||
824 | /* Goal is not achieved. We stop process if: | |
825 | ||
826 | - if expire reduced to zero. Otherwise, expire is halfed. | |
827 | - if table is not full. | |
828 | - if we are called from interrupt. | |
829 | - jiffies check is just fallback/debug loop breaker. | |
830 | We will not spin here for long time in any case. | |
831 | */ | |
832 | ||
833 | RT_CACHE_STAT_INC(gc_goal_miss); | |
834 | ||
835 | if (expire == 0) | |
836 | break; | |
837 | ||
838 | expire >>= 1; | |
839 | #if RT_CACHE_DEBUG >= 2 | |
840 | printk(KERN_DEBUG "expire>> %u %d %d %d\n", expire, | |
841 | atomic_read(&ipv4_dst_ops.entries), goal, i); | |
842 | #endif | |
843 | ||
844 | if (atomic_read(&ipv4_dst_ops.entries) < ip_rt_max_size) | |
845 | goto out; | |
846 | } while (!in_softirq() && time_before_eq(jiffies, now)); | |
847 | ||
848 | if (atomic_read(&ipv4_dst_ops.entries) < ip_rt_max_size) | |
849 | goto out; | |
850 | if (net_ratelimit()) | |
851 | printk(KERN_WARNING "dst cache overflow\n"); | |
852 | RT_CACHE_STAT_INC(gc_dst_overflow); | |
853 | return 1; | |
854 | ||
855 | work_done: | |
856 | expire += ip_rt_gc_min_interval; | |
857 | if (expire > ip_rt_gc_timeout || | |
858 | atomic_read(&ipv4_dst_ops.entries) < ipv4_dst_ops.gc_thresh) | |
859 | expire = ip_rt_gc_timeout; | |
860 | #if RT_CACHE_DEBUG >= 2 | |
861 | printk(KERN_DEBUG "expire++ %u %d %d %d\n", expire, | |
862 | atomic_read(&ipv4_dst_ops.entries), goal, rover); | |
863 | #endif | |
864 | out: return 0; | |
865 | } | |
866 | ||
867 | static int rt_intern_hash(unsigned hash, struct rtable *rt, struct rtable **rp) | |
868 | { | |
869 | struct rtable *rth, **rthp; | |
870 | unsigned long now; | |
871 | struct rtable *cand, **candp; | |
872 | u32 min_score; | |
873 | int chain_length; | |
874 | int attempts = !in_softirq(); | |
875 | ||
876 | restart: | |
877 | chain_length = 0; | |
878 | min_score = ~(u32)0; | |
879 | cand = NULL; | |
880 | candp = NULL; | |
881 | now = jiffies; | |
882 | ||
883 | rthp = &rt_hash_table[hash].chain; | |
884 | ||
885 | spin_lock_bh(&rt_hash_table[hash].lock); | |
886 | while ((rth = *rthp) != NULL) { | |
887 | #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED | |
888 | if (!(rth->u.dst.flags & DST_BALANCED) && | |
889 | compare_keys(&rth->fl, &rt->fl)) { | |
890 | #else | |
891 | if (compare_keys(&rth->fl, &rt->fl)) { | |
892 | #endif | |
893 | /* Put it first */ | |
894 | *rthp = rth->u.rt_next; | |
895 | /* | |
896 | * Since lookup is lockfree, the deletion | |
897 | * must be visible to another weakly ordered CPU before | |
898 | * the insertion at the start of the hash chain. | |
899 | */ | |
900 | rcu_assign_pointer(rth->u.rt_next, | |
901 | rt_hash_table[hash].chain); | |
902 | /* | |
903 | * Since lookup is lockfree, the update writes | |
904 | * must be ordered for consistency on SMP. | |
905 | */ | |
906 | rcu_assign_pointer(rt_hash_table[hash].chain, rth); | |
907 | ||
908 | rth->u.dst.__use++; | |
909 | dst_hold(&rth->u.dst); | |
910 | rth->u.dst.lastuse = now; | |
911 | spin_unlock_bh(&rt_hash_table[hash].lock); | |
912 | ||
913 | rt_drop(rt); | |
914 | *rp = rth; | |
915 | return 0; | |
916 | } | |
917 | ||
918 | if (!atomic_read(&rth->u.dst.__refcnt)) { | |
919 | u32 score = rt_score(rth); | |
920 | ||
921 | if (score <= min_score) { | |
922 | cand = rth; | |
923 | candp = rthp; | |
924 | min_score = score; | |
925 | } | |
926 | } | |
927 | ||
928 | chain_length++; | |
929 | ||
930 | rthp = &rth->u.rt_next; | |
931 | } | |
932 | ||
933 | if (cand) { | |
934 | /* ip_rt_gc_elasticity used to be average length of chain | |
935 | * length, when exceeded gc becomes really aggressive. | |
936 | * | |
937 | * The second limit is less certain. At the moment it allows | |
938 | * only 2 entries per bucket. We will see. | |
939 | */ | |
940 | if (chain_length > ip_rt_gc_elasticity) { | |
941 | *candp = cand->u.rt_next; | |
942 | rt_free(cand); | |
943 | } | |
944 | } | |
945 | ||
946 | /* Try to bind route to arp only if it is output | |
947 | route or unicast forwarding path. | |
948 | */ | |
949 | if (rt->rt_type == RTN_UNICAST || rt->fl.iif == 0) { | |
950 | int err = arp_bind_neighbour(&rt->u.dst); | |
951 | if (err) { | |
952 | spin_unlock_bh(&rt_hash_table[hash].lock); | |
953 | ||
954 | if (err != -ENOBUFS) { | |
955 | rt_drop(rt); | |
956 | return err; | |
957 | } | |
958 | ||
959 | /* Neighbour tables are full and nothing | |
960 | can be released. Try to shrink route cache, | |
961 | it is most likely it holds some neighbour records. | |
962 | */ | |
963 | if (attempts-- > 0) { | |
964 | int saved_elasticity = ip_rt_gc_elasticity; | |
965 | int saved_int = ip_rt_gc_min_interval; | |
966 | ip_rt_gc_elasticity = 1; | |
967 | ip_rt_gc_min_interval = 0; | |
968 | rt_garbage_collect(); | |
969 | ip_rt_gc_min_interval = saved_int; | |
970 | ip_rt_gc_elasticity = saved_elasticity; | |
971 | goto restart; | |
972 | } | |
973 | ||
974 | if (net_ratelimit()) | |
975 | printk(KERN_WARNING "Neighbour table overflow.\n"); | |
976 | rt_drop(rt); | |
977 | return -ENOBUFS; | |
978 | } | |
979 | } | |
980 | ||
981 | rt->u.rt_next = rt_hash_table[hash].chain; | |
982 | #if RT_CACHE_DEBUG >= 2 | |
983 | if (rt->u.rt_next) { | |
984 | struct rtable *trt; | |
985 | printk(KERN_DEBUG "rt_cache @%02x: %u.%u.%u.%u", hash, | |
986 | NIPQUAD(rt->rt_dst)); | |
987 | for (trt = rt->u.rt_next; trt; trt = trt->u.rt_next) | |
988 | printk(" . %u.%u.%u.%u", NIPQUAD(trt->rt_dst)); | |
989 | printk("\n"); | |
990 | } | |
991 | #endif | |
992 | rt_hash_table[hash].chain = rt; | |
993 | spin_unlock_bh(&rt_hash_table[hash].lock); | |
994 | *rp = rt; | |
995 | return 0; | |
996 | } | |
997 | ||
998 | void rt_bind_peer(struct rtable *rt, int create) | |
999 | { | |
1000 | static DEFINE_SPINLOCK(rt_peer_lock); | |
1001 | struct inet_peer *peer; | |
1002 | ||
1003 | peer = inet_getpeer(rt->rt_dst, create); | |
1004 | ||
1005 | spin_lock_bh(&rt_peer_lock); | |
1006 | if (rt->peer == NULL) { | |
1007 | rt->peer = peer; | |
1008 | peer = NULL; | |
1009 | } | |
1010 | spin_unlock_bh(&rt_peer_lock); | |
1011 | if (peer) | |
1012 | inet_putpeer(peer); | |
1013 | } | |
1014 | ||
1015 | /* | |
1016 | * Peer allocation may fail only in serious out-of-memory conditions. However | |
1017 | * we still can generate some output. | |
1018 | * Random ID selection looks a bit dangerous because we have no chances to | |
1019 | * select ID being unique in a reasonable period of time. | |
1020 | * But broken packet identifier may be better than no packet at all. | |
1021 | */ | |
1022 | static void ip_select_fb_ident(struct iphdr *iph) | |
1023 | { | |
1024 | static DEFINE_SPINLOCK(ip_fb_id_lock); | |
1025 | static u32 ip_fallback_id; | |
1026 | u32 salt; | |
1027 | ||
1028 | spin_lock_bh(&ip_fb_id_lock); | |
1029 | salt = secure_ip_id(ip_fallback_id ^ iph->daddr); | |
1030 | iph->id = htons(salt & 0xFFFF); | |
1031 | ip_fallback_id = salt; | |
1032 | spin_unlock_bh(&ip_fb_id_lock); | |
1033 | } | |
1034 | ||
1035 | void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more) | |
1036 | { | |
1037 | struct rtable *rt = (struct rtable *) dst; | |
1038 | ||
1039 | if (rt) { | |
1040 | if (rt->peer == NULL) | |
1041 | rt_bind_peer(rt, 1); | |
1042 | ||
1043 | /* If peer is attached to destination, it is never detached, | |
1044 | so that we need not to grab a lock to dereference it. | |
1045 | */ | |
1046 | if (rt->peer) { | |
1047 | iph->id = htons(inet_getid(rt->peer, more)); | |
1048 | return; | |
1049 | } | |
1050 | } else | |
9c2b3328 SH |
1051 | printk(KERN_DEBUG "rt_bind_peer(0) @%p\n", |
1052 | __builtin_return_address(0)); | |
1da177e4 LT |
1053 | |
1054 | ip_select_fb_ident(iph); | |
1055 | } | |
1056 | ||
1057 | static void rt_del(unsigned hash, struct rtable *rt) | |
1058 | { | |
1059 | struct rtable **rthp; | |
1060 | ||
1061 | spin_lock_bh(&rt_hash_table[hash].lock); | |
1062 | ip_rt_put(rt); | |
1063 | for (rthp = &rt_hash_table[hash].chain; *rthp; | |
1064 | rthp = &(*rthp)->u.rt_next) | |
1065 | if (*rthp == rt) { | |
1066 | *rthp = rt->u.rt_next; | |
1067 | rt_free(rt); | |
1068 | break; | |
1069 | } | |
1070 | spin_unlock_bh(&rt_hash_table[hash].lock); | |
1071 | } | |
1072 | ||
1073 | void ip_rt_redirect(u32 old_gw, u32 daddr, u32 new_gw, | |
1074 | u32 saddr, u8 tos, struct net_device *dev) | |
1075 | { | |
1076 | int i, k; | |
1077 | struct in_device *in_dev = in_dev_get(dev); | |
1078 | struct rtable *rth, **rthp; | |
1079 | u32 skeys[2] = { saddr, 0 }; | |
1080 | int ikeys[2] = { dev->ifindex, 0 }; | |
1081 | ||
1082 | tos &= IPTOS_RT_MASK; | |
1083 | ||
1084 | if (!in_dev) | |
1085 | return; | |
1086 | ||
1087 | if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) | |
1088 | || MULTICAST(new_gw) || BADCLASS(new_gw) || ZERONET(new_gw)) | |
1089 | goto reject_redirect; | |
1090 | ||
1091 | if (!IN_DEV_SHARED_MEDIA(in_dev)) { | |
1092 | if (!inet_addr_onlink(in_dev, new_gw, old_gw)) | |
1093 | goto reject_redirect; | |
1094 | if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev)) | |
1095 | goto reject_redirect; | |
1096 | } else { | |
1097 | if (inet_addr_type(new_gw) != RTN_UNICAST) | |
1098 | goto reject_redirect; | |
1099 | } | |
1100 | ||
1101 | for (i = 0; i < 2; i++) { | |
1102 | for (k = 0; k < 2; k++) { | |
1103 | unsigned hash = rt_hash_code(daddr, | |
1104 | skeys[i] ^ (ikeys[k] << 5), | |
1105 | tos); | |
1106 | ||
1107 | rthp=&rt_hash_table[hash].chain; | |
1108 | ||
1109 | rcu_read_lock(); | |
1110 | while ((rth = rcu_dereference(*rthp)) != NULL) { | |
1111 | struct rtable *rt; | |
1112 | ||
1113 | if (rth->fl.fl4_dst != daddr || | |
1114 | rth->fl.fl4_src != skeys[i] || | |
1115 | rth->fl.fl4_tos != tos || | |
1116 | rth->fl.oif != ikeys[k] || | |
1117 | rth->fl.iif != 0) { | |
1118 | rthp = &rth->u.rt_next; | |
1119 | continue; | |
1120 | } | |
1121 | ||
1122 | if (rth->rt_dst != daddr || | |
1123 | rth->rt_src != saddr || | |
1124 | rth->u.dst.error || | |
1125 | rth->rt_gateway != old_gw || | |
1126 | rth->u.dst.dev != dev) | |
1127 | break; | |
1128 | ||
1129 | dst_hold(&rth->u.dst); | |
1130 | rcu_read_unlock(); | |
1131 | ||
1132 | rt = dst_alloc(&ipv4_dst_ops); | |
1133 | if (rt == NULL) { | |
1134 | ip_rt_put(rth); | |
1135 | in_dev_put(in_dev); | |
1136 | return; | |
1137 | } | |
1138 | ||
1139 | /* Copy all the information. */ | |
1140 | *rt = *rth; | |
1141 | INIT_RCU_HEAD(&rt->u.dst.rcu_head); | |
1142 | rt->u.dst.__use = 1; | |
1143 | atomic_set(&rt->u.dst.__refcnt, 1); | |
1144 | rt->u.dst.child = NULL; | |
1145 | if (rt->u.dst.dev) | |
1146 | dev_hold(rt->u.dst.dev); | |
1147 | if (rt->idev) | |
1148 | in_dev_hold(rt->idev); | |
1149 | rt->u.dst.obsolete = 0; | |
1150 | rt->u.dst.lastuse = jiffies; | |
1151 | rt->u.dst.path = &rt->u.dst; | |
1152 | rt->u.dst.neighbour = NULL; | |
1153 | rt->u.dst.hh = NULL; | |
1154 | rt->u.dst.xfrm = NULL; | |
1155 | ||
1156 | rt->rt_flags |= RTCF_REDIRECTED; | |
1157 | ||
1158 | /* Gateway is different ... */ | |
1159 | rt->rt_gateway = new_gw; | |
1160 | ||
1161 | /* Redirect received -> path was valid */ | |
1162 | dst_confirm(&rth->u.dst); | |
1163 | ||
1164 | if (rt->peer) | |
1165 | atomic_inc(&rt->peer->refcnt); | |
1166 | ||
1167 | if (arp_bind_neighbour(&rt->u.dst) || | |
1168 | !(rt->u.dst.neighbour->nud_state & | |
1169 | NUD_VALID)) { | |
1170 | if (rt->u.dst.neighbour) | |
1171 | neigh_event_send(rt->u.dst.neighbour, NULL); | |
1172 | ip_rt_put(rth); | |
1173 | rt_drop(rt); | |
1174 | goto do_next; | |
1175 | } | |
1176 | ||
1177 | rt_del(hash, rth); | |
1178 | if (!rt_intern_hash(hash, rt, &rt)) | |
1179 | ip_rt_put(rt); | |
1180 | goto do_next; | |
1181 | } | |
1182 | rcu_read_unlock(); | |
1183 | do_next: | |
1184 | ; | |
1185 | } | |
1186 | } | |
1187 | in_dev_put(in_dev); | |
1188 | return; | |
1189 | ||
1190 | reject_redirect: | |
1191 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
1192 | if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) | |
1193 | printk(KERN_INFO "Redirect from %u.%u.%u.%u on %s about " | |
1194 | "%u.%u.%u.%u ignored.\n" | |
1195 | " Advised path = %u.%u.%u.%u -> %u.%u.%u.%u, " | |
1196 | "tos %02x\n", | |
1197 | NIPQUAD(old_gw), dev->name, NIPQUAD(new_gw), | |
1198 | NIPQUAD(saddr), NIPQUAD(daddr), tos); | |
1199 | #endif | |
1200 | in_dev_put(in_dev); | |
1201 | } | |
1202 | ||
1203 | static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst) | |
1204 | { | |
1205 | struct rtable *rt = (struct rtable*)dst; | |
1206 | struct dst_entry *ret = dst; | |
1207 | ||
1208 | if (rt) { | |
1209 | if (dst->obsolete) { | |
1210 | ip_rt_put(rt); | |
1211 | ret = NULL; | |
1212 | } else if ((rt->rt_flags & RTCF_REDIRECTED) || | |
1213 | rt->u.dst.expires) { | |
1214 | unsigned hash = rt_hash_code(rt->fl.fl4_dst, | |
1215 | rt->fl.fl4_src ^ | |
1216 | (rt->fl.oif << 5), | |
1217 | rt->fl.fl4_tos); | |
1218 | #if RT_CACHE_DEBUG >= 1 | |
1219 | printk(KERN_DEBUG "ip_rt_advice: redirect to " | |
1220 | "%u.%u.%u.%u/%02x dropped\n", | |
1221 | NIPQUAD(rt->rt_dst), rt->fl.fl4_tos); | |
1222 | #endif | |
1223 | rt_del(hash, rt); | |
1224 | ret = NULL; | |
1225 | } | |
1226 | } | |
1227 | return ret; | |
1228 | } | |
1229 | ||
1230 | /* | |
1231 | * Algorithm: | |
1232 | * 1. The first ip_rt_redirect_number redirects are sent | |
1233 | * with exponential backoff, then we stop sending them at all, | |
1234 | * assuming that the host ignores our redirects. | |
1235 | * 2. If we did not see packets requiring redirects | |
1236 | * during ip_rt_redirect_silence, we assume that the host | |
1237 | * forgot redirected route and start to send redirects again. | |
1238 | * | |
1239 | * This algorithm is much cheaper and more intelligent than dumb load limiting | |
1240 | * in icmp.c. | |
1241 | * | |
1242 | * NOTE. Do not forget to inhibit load limiting for redirects (redundant) | |
1243 | * and "frag. need" (breaks PMTU discovery) in icmp.c. | |
1244 | */ | |
1245 | ||
1246 | void ip_rt_send_redirect(struct sk_buff *skb) | |
1247 | { | |
1248 | struct rtable *rt = (struct rtable*)skb->dst; | |
1249 | struct in_device *in_dev = in_dev_get(rt->u.dst.dev); | |
1250 | ||
1251 | if (!in_dev) | |
1252 | return; | |
1253 | ||
1254 | if (!IN_DEV_TX_REDIRECTS(in_dev)) | |
1255 | goto out; | |
1256 | ||
1257 | /* No redirected packets during ip_rt_redirect_silence; | |
1258 | * reset the algorithm. | |
1259 | */ | |
1260 | if (time_after(jiffies, rt->u.dst.rate_last + ip_rt_redirect_silence)) | |
1261 | rt->u.dst.rate_tokens = 0; | |
1262 | ||
1263 | /* Too many ignored redirects; do not send anything | |
1264 | * set u.dst.rate_last to the last seen redirected packet. | |
1265 | */ | |
1266 | if (rt->u.dst.rate_tokens >= ip_rt_redirect_number) { | |
1267 | rt->u.dst.rate_last = jiffies; | |
1268 | goto out; | |
1269 | } | |
1270 | ||
1271 | /* Check for load limit; set rate_last to the latest sent | |
1272 | * redirect. | |
1273 | */ | |
1274 | if (time_after(jiffies, | |
1275 | (rt->u.dst.rate_last + | |
1276 | (ip_rt_redirect_load << rt->u.dst.rate_tokens)))) { | |
1277 | icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway); | |
1278 | rt->u.dst.rate_last = jiffies; | |
1279 | ++rt->u.dst.rate_tokens; | |
1280 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
1281 | if (IN_DEV_LOG_MARTIANS(in_dev) && | |
1282 | rt->u.dst.rate_tokens == ip_rt_redirect_number && | |
1283 | net_ratelimit()) | |
1284 | printk(KERN_WARNING "host %u.%u.%u.%u/if%d ignores " | |
1285 | "redirects for %u.%u.%u.%u to %u.%u.%u.%u.\n", | |
1286 | NIPQUAD(rt->rt_src), rt->rt_iif, | |
1287 | NIPQUAD(rt->rt_dst), NIPQUAD(rt->rt_gateway)); | |
1288 | #endif | |
1289 | } | |
1290 | out: | |
1291 | in_dev_put(in_dev); | |
1292 | } | |
1293 | ||
1294 | static int ip_error(struct sk_buff *skb) | |
1295 | { | |
1296 | struct rtable *rt = (struct rtable*)skb->dst; | |
1297 | unsigned long now; | |
1298 | int code; | |
1299 | ||
1300 | switch (rt->u.dst.error) { | |
1301 | case EINVAL: | |
1302 | default: | |
1303 | goto out; | |
1304 | case EHOSTUNREACH: | |
1305 | code = ICMP_HOST_UNREACH; | |
1306 | break; | |
1307 | case ENETUNREACH: | |
1308 | code = ICMP_NET_UNREACH; | |
1309 | break; | |
1310 | case EACCES: | |
1311 | code = ICMP_PKT_FILTERED; | |
1312 | break; | |
1313 | } | |
1314 | ||
1315 | now = jiffies; | |
1316 | rt->u.dst.rate_tokens += now - rt->u.dst.rate_last; | |
1317 | if (rt->u.dst.rate_tokens > ip_rt_error_burst) | |
1318 | rt->u.dst.rate_tokens = ip_rt_error_burst; | |
1319 | rt->u.dst.rate_last = now; | |
1320 | if (rt->u.dst.rate_tokens >= ip_rt_error_cost) { | |
1321 | rt->u.dst.rate_tokens -= ip_rt_error_cost; | |
1322 | icmp_send(skb, ICMP_DEST_UNREACH, code, 0); | |
1323 | } | |
1324 | ||
1325 | out: kfree_skb(skb); | |
1326 | return 0; | |
1327 | } | |
1328 | ||
1329 | /* | |
1330 | * The last two values are not from the RFC but | |
1331 | * are needed for AMPRnet AX.25 paths. | |
1332 | */ | |
1333 | ||
1334 | static unsigned short mtu_plateau[] = | |
1335 | {32000, 17914, 8166, 4352, 2002, 1492, 576, 296, 216, 128 }; | |
1336 | ||
1337 | static __inline__ unsigned short guess_mtu(unsigned short old_mtu) | |
1338 | { | |
1339 | int i; | |
1340 | ||
1341 | for (i = 0; i < ARRAY_SIZE(mtu_plateau); i++) | |
1342 | if (old_mtu > mtu_plateau[i]) | |
1343 | return mtu_plateau[i]; | |
1344 | return 68; | |
1345 | } | |
1346 | ||
1347 | unsigned short ip_rt_frag_needed(struct iphdr *iph, unsigned short new_mtu) | |
1348 | { | |
1349 | int i; | |
1350 | unsigned short old_mtu = ntohs(iph->tot_len); | |
1351 | struct rtable *rth; | |
1352 | u32 skeys[2] = { iph->saddr, 0, }; | |
1353 | u32 daddr = iph->daddr; | |
1354 | u8 tos = iph->tos & IPTOS_RT_MASK; | |
1355 | unsigned short est_mtu = 0; | |
1356 | ||
1357 | if (ipv4_config.no_pmtu_disc) | |
1358 | return 0; | |
1359 | ||
1360 | for (i = 0; i < 2; i++) { | |
1361 | unsigned hash = rt_hash_code(daddr, skeys[i], tos); | |
1362 | ||
1363 | rcu_read_lock(); | |
1364 | for (rth = rcu_dereference(rt_hash_table[hash].chain); rth; | |
1365 | rth = rcu_dereference(rth->u.rt_next)) { | |
1366 | if (rth->fl.fl4_dst == daddr && | |
1367 | rth->fl.fl4_src == skeys[i] && | |
1368 | rth->rt_dst == daddr && | |
1369 | rth->rt_src == iph->saddr && | |
1370 | rth->fl.fl4_tos == tos && | |
1371 | rth->fl.iif == 0 && | |
1372 | !(dst_metric_locked(&rth->u.dst, RTAX_MTU))) { | |
1373 | unsigned short mtu = new_mtu; | |
1374 | ||
1375 | if (new_mtu < 68 || new_mtu >= old_mtu) { | |
1376 | ||
1377 | /* BSD 4.2 compatibility hack :-( */ | |
1378 | if (mtu == 0 && | |
1379 | old_mtu >= rth->u.dst.metrics[RTAX_MTU-1] && | |
1380 | old_mtu >= 68 + (iph->ihl << 2)) | |
1381 | old_mtu -= iph->ihl << 2; | |
1382 | ||
1383 | mtu = guess_mtu(old_mtu); | |
1384 | } | |
1385 | if (mtu <= rth->u.dst.metrics[RTAX_MTU-1]) { | |
1386 | if (mtu < rth->u.dst.metrics[RTAX_MTU-1]) { | |
1387 | dst_confirm(&rth->u.dst); | |
1388 | if (mtu < ip_rt_min_pmtu) { | |
1389 | mtu = ip_rt_min_pmtu; | |
1390 | rth->u.dst.metrics[RTAX_LOCK-1] |= | |
1391 | (1 << RTAX_MTU); | |
1392 | } | |
1393 | rth->u.dst.metrics[RTAX_MTU-1] = mtu; | |
1394 | dst_set_expires(&rth->u.dst, | |
1395 | ip_rt_mtu_expires); | |
1396 | } | |
1397 | est_mtu = mtu; | |
1398 | } | |
1399 | } | |
1400 | } | |
1401 | rcu_read_unlock(); | |
1402 | } | |
1403 | return est_mtu ? : new_mtu; | |
1404 | } | |
1405 | ||
1406 | static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu) | |
1407 | { | |
1408 | if (dst->metrics[RTAX_MTU-1] > mtu && mtu >= 68 && | |
1409 | !(dst_metric_locked(dst, RTAX_MTU))) { | |
1410 | if (mtu < ip_rt_min_pmtu) { | |
1411 | mtu = ip_rt_min_pmtu; | |
1412 | dst->metrics[RTAX_LOCK-1] |= (1 << RTAX_MTU); | |
1413 | } | |
1414 | dst->metrics[RTAX_MTU-1] = mtu; | |
1415 | dst_set_expires(dst, ip_rt_mtu_expires); | |
1416 | } | |
1417 | } | |
1418 | ||
1419 | static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie) | |
1420 | { | |
1421 | return NULL; | |
1422 | } | |
1423 | ||
1424 | static void ipv4_dst_destroy(struct dst_entry *dst) | |
1425 | { | |
1426 | struct rtable *rt = (struct rtable *) dst; | |
1427 | struct inet_peer *peer = rt->peer; | |
1428 | struct in_device *idev = rt->idev; | |
1429 | ||
1430 | if (peer) { | |
1431 | rt->peer = NULL; | |
1432 | inet_putpeer(peer); | |
1433 | } | |
1434 | ||
1435 | if (idev) { | |
1436 | rt->idev = NULL; | |
1437 | in_dev_put(idev); | |
1438 | } | |
1439 | } | |
1440 | ||
1441 | static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev, | |
1442 | int how) | |
1443 | { | |
1444 | struct rtable *rt = (struct rtable *) dst; | |
1445 | struct in_device *idev = rt->idev; | |
1446 | if (dev != &loopback_dev && idev && idev->dev == dev) { | |
1447 | struct in_device *loopback_idev = in_dev_get(&loopback_dev); | |
1448 | if (loopback_idev) { | |
1449 | rt->idev = loopback_idev; | |
1450 | in_dev_put(idev); | |
1451 | } | |
1452 | } | |
1453 | } | |
1454 | ||
1455 | static void ipv4_link_failure(struct sk_buff *skb) | |
1456 | { | |
1457 | struct rtable *rt; | |
1458 | ||
1459 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0); | |
1460 | ||
1461 | rt = (struct rtable *) skb->dst; | |
1462 | if (rt) | |
1463 | dst_set_expires(&rt->u.dst, 0); | |
1464 | } | |
1465 | ||
1466 | static int ip_rt_bug(struct sk_buff *skb) | |
1467 | { | |
1468 | printk(KERN_DEBUG "ip_rt_bug: %u.%u.%u.%u -> %u.%u.%u.%u, %s\n", | |
1469 | NIPQUAD(skb->nh.iph->saddr), NIPQUAD(skb->nh.iph->daddr), | |
1470 | skb->dev ? skb->dev->name : "?"); | |
1471 | kfree_skb(skb); | |
1472 | return 0; | |
1473 | } | |
1474 | ||
1475 | /* | |
1476 | We do not cache source address of outgoing interface, | |
1477 | because it is used only by IP RR, TS and SRR options, | |
1478 | so that it out of fast path. | |
1479 | ||
1480 | BTW remember: "addr" is allowed to be not aligned | |
1481 | in IP options! | |
1482 | */ | |
1483 | ||
1484 | void ip_rt_get_source(u8 *addr, struct rtable *rt) | |
1485 | { | |
1486 | u32 src; | |
1487 | struct fib_result res; | |
1488 | ||
1489 | if (rt->fl.iif == 0) | |
1490 | src = rt->rt_src; | |
1491 | else if (fib_lookup(&rt->fl, &res) == 0) { | |
1492 | src = FIB_RES_PREFSRC(res); | |
1493 | fib_res_put(&res); | |
1494 | } else | |
1495 | src = inet_select_addr(rt->u.dst.dev, rt->rt_gateway, | |
1496 | RT_SCOPE_UNIVERSE); | |
1497 | memcpy(addr, &src, 4); | |
1498 | } | |
1499 | ||
1500 | #ifdef CONFIG_NET_CLS_ROUTE | |
1501 | static void set_class_tag(struct rtable *rt, u32 tag) | |
1502 | { | |
1503 | if (!(rt->u.dst.tclassid & 0xFFFF)) | |
1504 | rt->u.dst.tclassid |= tag & 0xFFFF; | |
1505 | if (!(rt->u.dst.tclassid & 0xFFFF0000)) | |
1506 | rt->u.dst.tclassid |= tag & 0xFFFF0000; | |
1507 | } | |
1508 | #endif | |
1509 | ||
1510 | static void rt_set_nexthop(struct rtable *rt, struct fib_result *res, u32 itag) | |
1511 | { | |
1512 | struct fib_info *fi = res->fi; | |
1513 | ||
1514 | if (fi) { | |
1515 | if (FIB_RES_GW(*res) && | |
1516 | FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK) | |
1517 | rt->rt_gateway = FIB_RES_GW(*res); | |
1518 | memcpy(rt->u.dst.metrics, fi->fib_metrics, | |
1519 | sizeof(rt->u.dst.metrics)); | |
1520 | if (fi->fib_mtu == 0) { | |
1521 | rt->u.dst.metrics[RTAX_MTU-1] = rt->u.dst.dev->mtu; | |
1522 | if (rt->u.dst.metrics[RTAX_LOCK-1] & (1 << RTAX_MTU) && | |
1523 | rt->rt_gateway != rt->rt_dst && | |
1524 | rt->u.dst.dev->mtu > 576) | |
1525 | rt->u.dst.metrics[RTAX_MTU-1] = 576; | |
1526 | } | |
1527 | #ifdef CONFIG_NET_CLS_ROUTE | |
1528 | rt->u.dst.tclassid = FIB_RES_NH(*res).nh_tclassid; | |
1529 | #endif | |
1530 | } else | |
1531 | rt->u.dst.metrics[RTAX_MTU-1]= rt->u.dst.dev->mtu; | |
1532 | ||
1533 | if (rt->u.dst.metrics[RTAX_HOPLIMIT-1] == 0) | |
1534 | rt->u.dst.metrics[RTAX_HOPLIMIT-1] = sysctl_ip_default_ttl; | |
1535 | if (rt->u.dst.metrics[RTAX_MTU-1] > IP_MAX_MTU) | |
1536 | rt->u.dst.metrics[RTAX_MTU-1] = IP_MAX_MTU; | |
1537 | if (rt->u.dst.metrics[RTAX_ADVMSS-1] == 0) | |
1538 | rt->u.dst.metrics[RTAX_ADVMSS-1] = max_t(unsigned int, rt->u.dst.dev->mtu - 40, | |
1539 | ip_rt_min_advmss); | |
1540 | if (rt->u.dst.metrics[RTAX_ADVMSS-1] > 65535 - 40) | |
1541 | rt->u.dst.metrics[RTAX_ADVMSS-1] = 65535 - 40; | |
1542 | ||
1543 | #ifdef CONFIG_NET_CLS_ROUTE | |
1544 | #ifdef CONFIG_IP_MULTIPLE_TABLES | |
1545 | set_class_tag(rt, fib_rules_tclass(res)); | |
1546 | #endif | |
1547 | set_class_tag(rt, itag); | |
1548 | #endif | |
1549 | rt->rt_type = res->type; | |
1550 | } | |
1551 | ||
1552 | static int ip_route_input_mc(struct sk_buff *skb, u32 daddr, u32 saddr, | |
1553 | u8 tos, struct net_device *dev, int our) | |
1554 | { | |
1555 | unsigned hash; | |
1556 | struct rtable *rth; | |
1557 | u32 spec_dst; | |
1558 | struct in_device *in_dev = in_dev_get(dev); | |
1559 | u32 itag = 0; | |
1560 | ||
1561 | /* Primary sanity checks. */ | |
1562 | ||
1563 | if (in_dev == NULL) | |
1564 | return -EINVAL; | |
1565 | ||
1566 | if (MULTICAST(saddr) || BADCLASS(saddr) || LOOPBACK(saddr) || | |
1567 | skb->protocol != htons(ETH_P_IP)) | |
1568 | goto e_inval; | |
1569 | ||
1570 | if (ZERONET(saddr)) { | |
1571 | if (!LOCAL_MCAST(daddr)) | |
1572 | goto e_inval; | |
1573 | spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK); | |
1574 | } else if (fib_validate_source(saddr, 0, tos, 0, | |
1575 | dev, &spec_dst, &itag) < 0) | |
1576 | goto e_inval; | |
1577 | ||
1578 | rth = dst_alloc(&ipv4_dst_ops); | |
1579 | if (!rth) | |
1580 | goto e_nobufs; | |
1581 | ||
1582 | rth->u.dst.output= ip_rt_bug; | |
1583 | ||
1584 | atomic_set(&rth->u.dst.__refcnt, 1); | |
1585 | rth->u.dst.flags= DST_HOST; | |
1586 | if (in_dev->cnf.no_policy) | |
1587 | rth->u.dst.flags |= DST_NOPOLICY; | |
1588 | rth->fl.fl4_dst = daddr; | |
1589 | rth->rt_dst = daddr; | |
1590 | rth->fl.fl4_tos = tos; | |
1591 | #ifdef CONFIG_IP_ROUTE_FWMARK | |
1592 | rth->fl.fl4_fwmark= skb->nfmark; | |
1593 | #endif | |
1594 | rth->fl.fl4_src = saddr; | |
1595 | rth->rt_src = saddr; | |
1596 | #ifdef CONFIG_NET_CLS_ROUTE | |
1597 | rth->u.dst.tclassid = itag; | |
1598 | #endif | |
1599 | rth->rt_iif = | |
1600 | rth->fl.iif = dev->ifindex; | |
1601 | rth->u.dst.dev = &loopback_dev; | |
1602 | dev_hold(rth->u.dst.dev); | |
1603 | rth->idev = in_dev_get(rth->u.dst.dev); | |
1604 | rth->fl.oif = 0; | |
1605 | rth->rt_gateway = daddr; | |
1606 | rth->rt_spec_dst= spec_dst; | |
1607 | rth->rt_type = RTN_MULTICAST; | |
1608 | rth->rt_flags = RTCF_MULTICAST; | |
1609 | if (our) { | |
1610 | rth->u.dst.input= ip_local_deliver; | |
1611 | rth->rt_flags |= RTCF_LOCAL; | |
1612 | } | |
1613 | ||
1614 | #ifdef CONFIG_IP_MROUTE | |
1615 | if (!LOCAL_MCAST(daddr) && IN_DEV_MFORWARD(in_dev)) | |
1616 | rth->u.dst.input = ip_mr_input; | |
1617 | #endif | |
1618 | RT_CACHE_STAT_INC(in_slow_mc); | |
1619 | ||
1620 | in_dev_put(in_dev); | |
1621 | hash = rt_hash_code(daddr, saddr ^ (dev->ifindex << 5), tos); | |
1622 | return rt_intern_hash(hash, rth, (struct rtable**) &skb->dst); | |
1623 | ||
1624 | e_nobufs: | |
1625 | in_dev_put(in_dev); | |
1626 | return -ENOBUFS; | |
1627 | ||
1628 | e_inval: | |
1629 | in_dev_put(in_dev); | |
1630 | return -EINVAL; | |
1631 | } | |
1632 | ||
1633 | ||
1634 | static void ip_handle_martian_source(struct net_device *dev, | |
1635 | struct in_device *in_dev, | |
1636 | struct sk_buff *skb, | |
1637 | u32 daddr, | |
1638 | u32 saddr) | |
1639 | { | |
1640 | RT_CACHE_STAT_INC(in_martian_src); | |
1641 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
1642 | if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) { | |
1643 | /* | |
1644 | * RFC1812 recommendation, if source is martian, | |
1645 | * the only hint is MAC header. | |
1646 | */ | |
1647 | printk(KERN_WARNING "martian source %u.%u.%u.%u from " | |
1648 | "%u.%u.%u.%u, on dev %s\n", | |
1649 | NIPQUAD(daddr), NIPQUAD(saddr), dev->name); | |
1650 | if (dev->hard_header_len) { | |
1651 | int i; | |
1652 | unsigned char *p = skb->mac.raw; | |
1653 | printk(KERN_WARNING "ll header: "); | |
1654 | for (i = 0; i < dev->hard_header_len; i++, p++) { | |
1655 | printk("%02x", *p); | |
1656 | if (i < (dev->hard_header_len - 1)) | |
1657 | printk(":"); | |
1658 | } | |
1659 | printk("\n"); | |
1660 | } | |
1661 | } | |
1662 | #endif | |
1663 | } | |
1664 | ||
1665 | static inline int __mkroute_input(struct sk_buff *skb, | |
1666 | struct fib_result* res, | |
1667 | struct in_device *in_dev, | |
1668 | u32 daddr, u32 saddr, u32 tos, | |
1669 | struct rtable **result) | |
1670 | { | |
1671 | ||
1672 | struct rtable *rth; | |
1673 | int err; | |
1674 | struct in_device *out_dev; | |
1675 | unsigned flags = 0; | |
1676 | u32 spec_dst, itag; | |
1677 | ||
1678 | /* get a working reference to the output device */ | |
1679 | out_dev = in_dev_get(FIB_RES_DEV(*res)); | |
1680 | if (out_dev == NULL) { | |
1681 | if (net_ratelimit()) | |
1682 | printk(KERN_CRIT "Bug in ip_route_input" \ | |
1683 | "_slow(). Please, report\n"); | |
1684 | return -EINVAL; | |
1685 | } | |
1686 | ||
1687 | ||
1688 | err = fib_validate_source(saddr, daddr, tos, FIB_RES_OIF(*res), | |
1689 | in_dev->dev, &spec_dst, &itag); | |
1690 | if (err < 0) { | |
1691 | ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr, | |
1692 | saddr); | |
1693 | ||
1694 | err = -EINVAL; | |
1695 | goto cleanup; | |
1696 | } | |
1697 | ||
1698 | if (err) | |
1699 | flags |= RTCF_DIRECTSRC; | |
1700 | ||
1701 | if (out_dev == in_dev && err && !(flags & (RTCF_NAT | RTCF_MASQ)) && | |
1702 | (IN_DEV_SHARED_MEDIA(out_dev) || | |
1703 | inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res)))) | |
1704 | flags |= RTCF_DOREDIRECT; | |
1705 | ||
1706 | if (skb->protocol != htons(ETH_P_IP)) { | |
1707 | /* Not IP (i.e. ARP). Do not create route, if it is | |
1708 | * invalid for proxy arp. DNAT routes are always valid. | |
1709 | */ | |
1710 | if (out_dev == in_dev && !(flags & RTCF_DNAT)) { | |
1711 | err = -EINVAL; | |
1712 | goto cleanup; | |
1713 | } | |
1714 | } | |
1715 | ||
1716 | ||
1717 | rth = dst_alloc(&ipv4_dst_ops); | |
1718 | if (!rth) { | |
1719 | err = -ENOBUFS; | |
1720 | goto cleanup; | |
1721 | } | |
1722 | ||
1723 | rth->u.dst.flags= DST_HOST; | |
1724 | #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED | |
1725 | if (res->fi->fib_nhs > 1) | |
1726 | rth->u.dst.flags |= DST_BALANCED; | |
1727 | #endif | |
1728 | if (in_dev->cnf.no_policy) | |
1729 | rth->u.dst.flags |= DST_NOPOLICY; | |
1730 | if (in_dev->cnf.no_xfrm) | |
1731 | rth->u.dst.flags |= DST_NOXFRM; | |
1732 | rth->fl.fl4_dst = daddr; | |
1733 | rth->rt_dst = daddr; | |
1734 | rth->fl.fl4_tos = tos; | |
1735 | #ifdef CONFIG_IP_ROUTE_FWMARK | |
1736 | rth->fl.fl4_fwmark= skb->nfmark; | |
1737 | #endif | |
1738 | rth->fl.fl4_src = saddr; | |
1739 | rth->rt_src = saddr; | |
1740 | rth->rt_gateway = daddr; | |
1741 | rth->rt_iif = | |
1742 | rth->fl.iif = in_dev->dev->ifindex; | |
1743 | rth->u.dst.dev = (out_dev)->dev; | |
1744 | dev_hold(rth->u.dst.dev); | |
1745 | rth->idev = in_dev_get(rth->u.dst.dev); | |
1746 | rth->fl.oif = 0; | |
1747 | rth->rt_spec_dst= spec_dst; | |
1748 | ||
1749 | rth->u.dst.input = ip_forward; | |
1750 | rth->u.dst.output = ip_output; | |
1751 | ||
1752 | rt_set_nexthop(rth, res, itag); | |
1753 | ||
1754 | rth->rt_flags = flags; | |
1755 | ||
1756 | *result = rth; | |
1757 | err = 0; | |
1758 | cleanup: | |
1759 | /* release the working reference to the output device */ | |
1760 | in_dev_put(out_dev); | |
1761 | return err; | |
1762 | } | |
1763 | ||
1764 | static inline int ip_mkroute_input_def(struct sk_buff *skb, | |
1765 | struct fib_result* res, | |
1766 | const struct flowi *fl, | |
1767 | struct in_device *in_dev, | |
1768 | u32 daddr, u32 saddr, u32 tos) | |
1769 | { | |
1770 | struct rtable* rth; | |
1771 | int err; | |
1772 | unsigned hash; | |
1773 | ||
1774 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
1775 | if (res->fi && res->fi->fib_nhs > 1 && fl->oif == 0) | |
1776 | fib_select_multipath(fl, res); | |
1777 | #endif | |
1778 | ||
1779 | /* create a routing cache entry */ | |
1780 | err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, &rth); | |
1781 | if (err) | |
1782 | return err; | |
1783 | atomic_set(&rth->u.dst.__refcnt, 1); | |
1784 | ||
1785 | /* put it into the cache */ | |
1786 | hash = rt_hash_code(daddr, saddr ^ (fl->iif << 5), tos); | |
1787 | return rt_intern_hash(hash, rth, (struct rtable**)&skb->dst); | |
1788 | } | |
1789 | ||
1790 | static inline int ip_mkroute_input(struct sk_buff *skb, | |
1791 | struct fib_result* res, | |
1792 | const struct flowi *fl, | |
1793 | struct in_device *in_dev, | |
1794 | u32 daddr, u32 saddr, u32 tos) | |
1795 | { | |
1796 | #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED | |
1797 | struct rtable* rth; | |
1798 | unsigned char hop, hopcount, lasthop; | |
1799 | int err = -EINVAL; | |
1800 | unsigned int hash; | |
1801 | ||
1802 | if (res->fi) | |
1803 | hopcount = res->fi->fib_nhs; | |
1804 | else | |
1805 | hopcount = 1; | |
1806 | ||
1807 | lasthop = hopcount - 1; | |
1808 | ||
1809 | /* distinguish between multipath and singlepath */ | |
1810 | if (hopcount < 2) | |
1811 | return ip_mkroute_input_def(skb, res, fl, in_dev, daddr, | |
1812 | saddr, tos); | |
1813 | ||
1814 | /* add all alternatives to the routing cache */ | |
1815 | for (hop = 0; hop < hopcount; hop++) { | |
1816 | res->nh_sel = hop; | |
1817 | ||
1818 | /* create a routing cache entry */ | |
1819 | err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, | |
1820 | &rth); | |
1821 | if (err) | |
1822 | return err; | |
1823 | ||
1824 | /* put it into the cache */ | |
1825 | hash = rt_hash_code(daddr, saddr ^ (fl->iif << 5), tos); | |
1826 | err = rt_intern_hash(hash, rth, (struct rtable**)&skb->dst); | |
1827 | if (err) | |
1828 | return err; | |
1829 | ||
1830 | /* forward hop information to multipath impl. */ | |
1831 | multipath_set_nhinfo(rth, | |
1832 | FIB_RES_NETWORK(*res), | |
1833 | FIB_RES_NETMASK(*res), | |
1834 | res->prefixlen, | |
1835 | &FIB_RES_NH(*res)); | |
1836 | ||
1837 | /* only for the last hop the reference count is handled | |
1838 | * outside | |
1839 | */ | |
1840 | if (hop == lasthop) | |
1841 | atomic_set(&(skb->dst->__refcnt), 1); | |
1842 | } | |
1843 | return err; | |
1844 | #else /* CONFIG_IP_ROUTE_MULTIPATH_CACHED */ | |
1845 | return ip_mkroute_input_def(skb, res, fl, in_dev, daddr, saddr, tos); | |
1846 | #endif /* CONFIG_IP_ROUTE_MULTIPATH_CACHED */ | |
1847 | } | |
1848 | ||
1849 | ||
1850 | /* | |
1851 | * NOTE. We drop all the packets that has local source | |
1852 | * addresses, because every properly looped back packet | |
1853 | * must have correct destination already attached by output routine. | |
1854 | * | |
1855 | * Such approach solves two big problems: | |
1856 | * 1. Not simplex devices are handled properly. | |
1857 | * 2. IP spoofing attempts are filtered with 100% of guarantee. | |
1858 | */ | |
1859 | ||
1860 | static int ip_route_input_slow(struct sk_buff *skb, u32 daddr, u32 saddr, | |
1861 | u8 tos, struct net_device *dev) | |
1862 | { | |
1863 | struct fib_result res; | |
1864 | struct in_device *in_dev = in_dev_get(dev); | |
1865 | struct flowi fl = { .nl_u = { .ip4_u = | |
1866 | { .daddr = daddr, | |
1867 | .saddr = saddr, | |
1868 | .tos = tos, | |
1869 | .scope = RT_SCOPE_UNIVERSE, | |
1870 | #ifdef CONFIG_IP_ROUTE_FWMARK | |
1871 | .fwmark = skb->nfmark | |
1872 | #endif | |
1873 | } }, | |
1874 | .iif = dev->ifindex }; | |
1875 | unsigned flags = 0; | |
1876 | u32 itag = 0; | |
1877 | struct rtable * rth; | |
1878 | unsigned hash; | |
1879 | u32 spec_dst; | |
1880 | int err = -EINVAL; | |
1881 | int free_res = 0; | |
1882 | ||
1883 | /* IP on this device is disabled. */ | |
1884 | ||
1885 | if (!in_dev) | |
1886 | goto out; | |
1887 | ||
1888 | /* Check for the most weird martians, which can be not detected | |
1889 | by fib_lookup. | |
1890 | */ | |
1891 | ||
1892 | if (MULTICAST(saddr) || BADCLASS(saddr) || LOOPBACK(saddr)) | |
1893 | goto martian_source; | |
1894 | ||
1895 | if (daddr == 0xFFFFFFFF || (saddr == 0 && daddr == 0)) | |
1896 | goto brd_input; | |
1897 | ||
1898 | /* Accept zero addresses only to limited broadcast; | |
1899 | * I even do not know to fix it or not. Waiting for complains :-) | |
1900 | */ | |
1901 | if (ZERONET(saddr)) | |
1902 | goto martian_source; | |
1903 | ||
1904 | if (BADCLASS(daddr) || ZERONET(daddr) || LOOPBACK(daddr)) | |
1905 | goto martian_destination; | |
1906 | ||
1907 | /* | |
1908 | * Now we are ready to route packet. | |
1909 | */ | |
1910 | if ((err = fib_lookup(&fl, &res)) != 0) { | |
1911 | if (!IN_DEV_FORWARD(in_dev)) | |
1912 | goto e_inval; | |
1913 | goto no_route; | |
1914 | } | |
1915 | free_res = 1; | |
1916 | ||
1917 | RT_CACHE_STAT_INC(in_slow_tot); | |
1918 | ||
1919 | if (res.type == RTN_BROADCAST) | |
1920 | goto brd_input; | |
1921 | ||
1922 | if (res.type == RTN_LOCAL) { | |
1923 | int result; | |
1924 | result = fib_validate_source(saddr, daddr, tos, | |
1925 | loopback_dev.ifindex, | |
1926 | dev, &spec_dst, &itag); | |
1927 | if (result < 0) | |
1928 | goto martian_source; | |
1929 | if (result) | |
1930 | flags |= RTCF_DIRECTSRC; | |
1931 | spec_dst = daddr; | |
1932 | goto local_input; | |
1933 | } | |
1934 | ||
1935 | if (!IN_DEV_FORWARD(in_dev)) | |
1936 | goto e_inval; | |
1937 | if (res.type != RTN_UNICAST) | |
1938 | goto martian_destination; | |
1939 | ||
1940 | err = ip_mkroute_input(skb, &res, &fl, in_dev, daddr, saddr, tos); | |
1941 | if (err == -ENOBUFS) | |
1942 | goto e_nobufs; | |
1943 | if (err == -EINVAL) | |
1944 | goto e_inval; | |
1945 | ||
1946 | done: | |
1947 | in_dev_put(in_dev); | |
1948 | if (free_res) | |
1949 | fib_res_put(&res); | |
1950 | out: return err; | |
1951 | ||
1952 | brd_input: | |
1953 | if (skb->protocol != htons(ETH_P_IP)) | |
1954 | goto e_inval; | |
1955 | ||
1956 | if (ZERONET(saddr)) | |
1957 | spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK); | |
1958 | else { | |
1959 | err = fib_validate_source(saddr, 0, tos, 0, dev, &spec_dst, | |
1960 | &itag); | |
1961 | if (err < 0) | |
1962 | goto martian_source; | |
1963 | if (err) | |
1964 | flags |= RTCF_DIRECTSRC; | |
1965 | } | |
1966 | flags |= RTCF_BROADCAST; | |
1967 | res.type = RTN_BROADCAST; | |
1968 | RT_CACHE_STAT_INC(in_brd); | |
1969 | ||
1970 | local_input: | |
1971 | rth = dst_alloc(&ipv4_dst_ops); | |
1972 | if (!rth) | |
1973 | goto e_nobufs; | |
1974 | ||
1975 | rth->u.dst.output= ip_rt_bug; | |
1976 | ||
1977 | atomic_set(&rth->u.dst.__refcnt, 1); | |
1978 | rth->u.dst.flags= DST_HOST; | |
1979 | if (in_dev->cnf.no_policy) | |
1980 | rth->u.dst.flags |= DST_NOPOLICY; | |
1981 | rth->fl.fl4_dst = daddr; | |
1982 | rth->rt_dst = daddr; | |
1983 | rth->fl.fl4_tos = tos; | |
1984 | #ifdef CONFIG_IP_ROUTE_FWMARK | |
1985 | rth->fl.fl4_fwmark= skb->nfmark; | |
1986 | #endif | |
1987 | rth->fl.fl4_src = saddr; | |
1988 | rth->rt_src = saddr; | |
1989 | #ifdef CONFIG_NET_CLS_ROUTE | |
1990 | rth->u.dst.tclassid = itag; | |
1991 | #endif | |
1992 | rth->rt_iif = | |
1993 | rth->fl.iif = dev->ifindex; | |
1994 | rth->u.dst.dev = &loopback_dev; | |
1995 | dev_hold(rth->u.dst.dev); | |
1996 | rth->idev = in_dev_get(rth->u.dst.dev); | |
1997 | rth->rt_gateway = daddr; | |
1998 | rth->rt_spec_dst= spec_dst; | |
1999 | rth->u.dst.input= ip_local_deliver; | |
2000 | rth->rt_flags = flags|RTCF_LOCAL; | |
2001 | if (res.type == RTN_UNREACHABLE) { | |
2002 | rth->u.dst.input= ip_error; | |
2003 | rth->u.dst.error= -err; | |
2004 | rth->rt_flags &= ~RTCF_LOCAL; | |
2005 | } | |
2006 | rth->rt_type = res.type; | |
2007 | hash = rt_hash_code(daddr, saddr ^ (fl.iif << 5), tos); | |
2008 | err = rt_intern_hash(hash, rth, (struct rtable**)&skb->dst); | |
2009 | goto done; | |
2010 | ||
2011 | no_route: | |
2012 | RT_CACHE_STAT_INC(in_no_route); | |
2013 | spec_dst = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE); | |
2014 | res.type = RTN_UNREACHABLE; | |
2015 | goto local_input; | |
2016 | ||
2017 | /* | |
2018 | * Do not cache martian addresses: they should be logged (RFC1812) | |
2019 | */ | |
2020 | martian_destination: | |
2021 | RT_CACHE_STAT_INC(in_martian_dst); | |
2022 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
2023 | if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) | |
2024 | printk(KERN_WARNING "martian destination %u.%u.%u.%u from " | |
2025 | "%u.%u.%u.%u, dev %s\n", | |
2026 | NIPQUAD(daddr), NIPQUAD(saddr), dev->name); | |
2027 | #endif | |
2028 | e_inval: | |
2029 | err = -EINVAL; | |
2030 | goto done; | |
2031 | ||
2032 | e_nobufs: | |
2033 | err = -ENOBUFS; | |
2034 | goto done; | |
2035 | ||
2036 | martian_source: | |
2037 | ip_handle_martian_source(dev, in_dev, skb, daddr, saddr); | |
2038 | goto e_inval; | |
2039 | } | |
2040 | ||
2041 | int ip_route_input(struct sk_buff *skb, u32 daddr, u32 saddr, | |
2042 | u8 tos, struct net_device *dev) | |
2043 | { | |
2044 | struct rtable * rth; | |
2045 | unsigned hash; | |
2046 | int iif = dev->ifindex; | |
2047 | ||
2048 | tos &= IPTOS_RT_MASK; | |
2049 | hash = rt_hash_code(daddr, saddr ^ (iif << 5), tos); | |
2050 | ||
2051 | rcu_read_lock(); | |
2052 | for (rth = rcu_dereference(rt_hash_table[hash].chain); rth; | |
2053 | rth = rcu_dereference(rth->u.rt_next)) { | |
2054 | if (rth->fl.fl4_dst == daddr && | |
2055 | rth->fl.fl4_src == saddr && | |
2056 | rth->fl.iif == iif && | |
2057 | rth->fl.oif == 0 && | |
2058 | #ifdef CONFIG_IP_ROUTE_FWMARK | |
2059 | rth->fl.fl4_fwmark == skb->nfmark && | |
2060 | #endif | |
2061 | rth->fl.fl4_tos == tos) { | |
2062 | rth->u.dst.lastuse = jiffies; | |
2063 | dst_hold(&rth->u.dst); | |
2064 | rth->u.dst.__use++; | |
2065 | RT_CACHE_STAT_INC(in_hit); | |
2066 | rcu_read_unlock(); | |
2067 | skb->dst = (struct dst_entry*)rth; | |
2068 | return 0; | |
2069 | } | |
2070 | RT_CACHE_STAT_INC(in_hlist_search); | |
2071 | } | |
2072 | rcu_read_unlock(); | |
2073 | ||
2074 | /* Multicast recognition logic is moved from route cache to here. | |
2075 | The problem was that too many Ethernet cards have broken/missing | |
2076 | hardware multicast filters :-( As result the host on multicasting | |
2077 | network acquires a lot of useless route cache entries, sort of | |
2078 | SDR messages from all the world. Now we try to get rid of them. | |
2079 | Really, provided software IP multicast filter is organized | |
2080 | reasonably (at least, hashed), it does not result in a slowdown | |
2081 | comparing with route cache reject entries. | |
2082 | Note, that multicast routers are not affected, because | |
2083 | route cache entry is created eventually. | |
2084 | */ | |
2085 | if (MULTICAST(daddr)) { | |
2086 | struct in_device *in_dev; | |
2087 | ||
2088 | rcu_read_lock(); | |
2089 | if ((in_dev = __in_dev_get(dev)) != NULL) { | |
2090 | int our = ip_check_mc(in_dev, daddr, saddr, | |
2091 | skb->nh.iph->protocol); | |
2092 | if (our | |
2093 | #ifdef CONFIG_IP_MROUTE | |
2094 | || (!LOCAL_MCAST(daddr) && IN_DEV_MFORWARD(in_dev)) | |
2095 | #endif | |
2096 | ) { | |
2097 | rcu_read_unlock(); | |
2098 | return ip_route_input_mc(skb, daddr, saddr, | |
2099 | tos, dev, our); | |
2100 | } | |
2101 | } | |
2102 | rcu_read_unlock(); | |
2103 | return -EINVAL; | |
2104 | } | |
2105 | return ip_route_input_slow(skb, daddr, saddr, tos, dev); | |
2106 | } | |
2107 | ||
2108 | static inline int __mkroute_output(struct rtable **result, | |
2109 | struct fib_result* res, | |
2110 | const struct flowi *fl, | |
2111 | const struct flowi *oldflp, | |
2112 | struct net_device *dev_out, | |
2113 | unsigned flags) | |
2114 | { | |
2115 | struct rtable *rth; | |
2116 | struct in_device *in_dev; | |
2117 | u32 tos = RT_FL_TOS(oldflp); | |
2118 | int err = 0; | |
2119 | ||
2120 | if (LOOPBACK(fl->fl4_src) && !(dev_out->flags&IFF_LOOPBACK)) | |
2121 | return -EINVAL; | |
2122 | ||
2123 | if (fl->fl4_dst == 0xFFFFFFFF) | |
2124 | res->type = RTN_BROADCAST; | |
2125 | else if (MULTICAST(fl->fl4_dst)) | |
2126 | res->type = RTN_MULTICAST; | |
2127 | else if (BADCLASS(fl->fl4_dst) || ZERONET(fl->fl4_dst)) | |
2128 | return -EINVAL; | |
2129 | ||
2130 | if (dev_out->flags & IFF_LOOPBACK) | |
2131 | flags |= RTCF_LOCAL; | |
2132 | ||
2133 | /* get work reference to inet device */ | |
2134 | in_dev = in_dev_get(dev_out); | |
2135 | if (!in_dev) | |
2136 | return -EINVAL; | |
2137 | ||
2138 | if (res->type == RTN_BROADCAST) { | |
2139 | flags |= RTCF_BROADCAST | RTCF_LOCAL; | |
2140 | if (res->fi) { | |
2141 | fib_info_put(res->fi); | |
2142 | res->fi = NULL; | |
2143 | } | |
2144 | } else if (res->type == RTN_MULTICAST) { | |
2145 | flags |= RTCF_MULTICAST|RTCF_LOCAL; | |
2146 | if (!ip_check_mc(in_dev, oldflp->fl4_dst, oldflp->fl4_src, | |
2147 | oldflp->proto)) | |
2148 | flags &= ~RTCF_LOCAL; | |
2149 | /* If multicast route do not exist use | |
2150 | default one, but do not gateway in this case. | |
2151 | Yes, it is hack. | |
2152 | */ | |
2153 | if (res->fi && res->prefixlen < 4) { | |
2154 | fib_info_put(res->fi); | |
2155 | res->fi = NULL; | |
2156 | } | |
2157 | } | |
2158 | ||
2159 | ||
2160 | rth = dst_alloc(&ipv4_dst_ops); | |
2161 | if (!rth) { | |
2162 | err = -ENOBUFS; | |
2163 | goto cleanup; | |
2164 | } | |
2165 | ||
2166 | rth->u.dst.flags= DST_HOST; | |
2167 | #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED | |
2168 | if (res->fi) { | |
2169 | rth->rt_multipath_alg = res->fi->fib_mp_alg; | |
2170 | if (res->fi->fib_nhs > 1) | |
2171 | rth->u.dst.flags |= DST_BALANCED; | |
2172 | } | |
2173 | #endif | |
2174 | if (in_dev->cnf.no_xfrm) | |
2175 | rth->u.dst.flags |= DST_NOXFRM; | |
2176 | if (in_dev->cnf.no_policy) | |
2177 | rth->u.dst.flags |= DST_NOPOLICY; | |
2178 | ||
2179 | rth->fl.fl4_dst = oldflp->fl4_dst; | |
2180 | rth->fl.fl4_tos = tos; | |
2181 | rth->fl.fl4_src = oldflp->fl4_src; | |
2182 | rth->fl.oif = oldflp->oif; | |
2183 | #ifdef CONFIG_IP_ROUTE_FWMARK | |
2184 | rth->fl.fl4_fwmark= oldflp->fl4_fwmark; | |
2185 | #endif | |
2186 | rth->rt_dst = fl->fl4_dst; | |
2187 | rth->rt_src = fl->fl4_src; | |
2188 | rth->rt_iif = oldflp->oif ? : dev_out->ifindex; | |
2189 | /* get references to the devices that are to be hold by the routing | |
2190 | cache entry */ | |
2191 | rth->u.dst.dev = dev_out; | |
2192 | dev_hold(dev_out); | |
2193 | rth->idev = in_dev_get(dev_out); | |
2194 | rth->rt_gateway = fl->fl4_dst; | |
2195 | rth->rt_spec_dst= fl->fl4_src; | |
2196 | ||
2197 | rth->u.dst.output=ip_output; | |
2198 | ||
2199 | RT_CACHE_STAT_INC(out_slow_tot); | |
2200 | ||
2201 | if (flags & RTCF_LOCAL) { | |
2202 | rth->u.dst.input = ip_local_deliver; | |
2203 | rth->rt_spec_dst = fl->fl4_dst; | |
2204 | } | |
2205 | if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) { | |
2206 | rth->rt_spec_dst = fl->fl4_src; | |
2207 | if (flags & RTCF_LOCAL && | |
2208 | !(dev_out->flags & IFF_LOOPBACK)) { | |
2209 | rth->u.dst.output = ip_mc_output; | |
2210 | RT_CACHE_STAT_INC(out_slow_mc); | |
2211 | } | |
2212 | #ifdef CONFIG_IP_MROUTE | |
2213 | if (res->type == RTN_MULTICAST) { | |
2214 | if (IN_DEV_MFORWARD(in_dev) && | |
2215 | !LOCAL_MCAST(oldflp->fl4_dst)) { | |
2216 | rth->u.dst.input = ip_mr_input; | |
2217 | rth->u.dst.output = ip_mc_output; | |
2218 | } | |
2219 | } | |
2220 | #endif | |
2221 | } | |
2222 | ||
2223 | rt_set_nexthop(rth, res, 0); | |
2224 | ||
2225 | rth->rt_flags = flags; | |
2226 | ||
2227 | *result = rth; | |
2228 | cleanup: | |
2229 | /* release work reference to inet device */ | |
2230 | in_dev_put(in_dev); | |
2231 | ||
2232 | return err; | |
2233 | } | |
2234 | ||
2235 | static inline int ip_mkroute_output_def(struct rtable **rp, | |
2236 | struct fib_result* res, | |
2237 | const struct flowi *fl, | |
2238 | const struct flowi *oldflp, | |
2239 | struct net_device *dev_out, | |
2240 | unsigned flags) | |
2241 | { | |
2242 | struct rtable *rth; | |
2243 | int err = __mkroute_output(&rth, res, fl, oldflp, dev_out, flags); | |
2244 | unsigned hash; | |
2245 | if (err == 0) { | |
2246 | u32 tos = RT_FL_TOS(oldflp); | |
2247 | ||
2248 | atomic_set(&rth->u.dst.__refcnt, 1); | |
2249 | ||
2250 | hash = rt_hash_code(oldflp->fl4_dst, | |
2251 | oldflp->fl4_src ^ (oldflp->oif << 5), tos); | |
2252 | err = rt_intern_hash(hash, rth, rp); | |
2253 | } | |
2254 | ||
2255 | return err; | |
2256 | } | |
2257 | ||
2258 | static inline int ip_mkroute_output(struct rtable** rp, | |
2259 | struct fib_result* res, | |
2260 | const struct flowi *fl, | |
2261 | const struct flowi *oldflp, | |
2262 | struct net_device *dev_out, | |
2263 | unsigned flags) | |
2264 | { | |
2265 | #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED | |
2266 | u32 tos = RT_FL_TOS(oldflp); | |
2267 | unsigned char hop; | |
2268 | unsigned hash; | |
2269 | int err = -EINVAL; | |
2270 | struct rtable *rth; | |
2271 | ||
2272 | if (res->fi && res->fi->fib_nhs > 1) { | |
2273 | unsigned char hopcount = res->fi->fib_nhs; | |
2274 | ||
2275 | for (hop = 0; hop < hopcount; hop++) { | |
2276 | struct net_device *dev2nexthop; | |
2277 | ||
2278 | res->nh_sel = hop; | |
2279 | ||
2280 | /* hold a work reference to the output device */ | |
2281 | dev2nexthop = FIB_RES_DEV(*res); | |
2282 | dev_hold(dev2nexthop); | |
2283 | ||
2284 | err = __mkroute_output(&rth, res, fl, oldflp, | |
2285 | dev2nexthop, flags); | |
2286 | ||
2287 | if (err != 0) | |
2288 | goto cleanup; | |
2289 | ||
2290 | hash = rt_hash_code(oldflp->fl4_dst, | |
2291 | oldflp->fl4_src ^ | |
2292 | (oldflp->oif << 5), tos); | |
2293 | err = rt_intern_hash(hash, rth, rp); | |
2294 | ||
2295 | /* forward hop information to multipath impl. */ | |
2296 | multipath_set_nhinfo(rth, | |
2297 | FIB_RES_NETWORK(*res), | |
2298 | FIB_RES_NETMASK(*res), | |
2299 | res->prefixlen, | |
2300 | &FIB_RES_NH(*res)); | |
2301 | cleanup: | |
2302 | /* release work reference to output device */ | |
2303 | dev_put(dev2nexthop); | |
2304 | ||
2305 | if (err != 0) | |
2306 | return err; | |
2307 | } | |
2308 | atomic_set(&(*rp)->u.dst.__refcnt, 1); | |
2309 | return err; | |
2310 | } else { | |
2311 | return ip_mkroute_output_def(rp, res, fl, oldflp, dev_out, | |
2312 | flags); | |
2313 | } | |
2314 | #else /* CONFIG_IP_ROUTE_MULTIPATH_CACHED */ | |
2315 | return ip_mkroute_output_def(rp, res, fl, oldflp, dev_out, flags); | |
2316 | #endif | |
2317 | } | |
2318 | ||
2319 | /* | |
2320 | * Major route resolver routine. | |
2321 | */ | |
2322 | ||
2323 | static int ip_route_output_slow(struct rtable **rp, const struct flowi *oldflp) | |
2324 | { | |
2325 | u32 tos = RT_FL_TOS(oldflp); | |
2326 | struct flowi fl = { .nl_u = { .ip4_u = | |
2327 | { .daddr = oldflp->fl4_dst, | |
2328 | .saddr = oldflp->fl4_src, | |
2329 | .tos = tos & IPTOS_RT_MASK, | |
2330 | .scope = ((tos & RTO_ONLINK) ? | |
2331 | RT_SCOPE_LINK : | |
2332 | RT_SCOPE_UNIVERSE), | |
2333 | #ifdef CONFIG_IP_ROUTE_FWMARK | |
2334 | .fwmark = oldflp->fl4_fwmark | |
2335 | #endif | |
2336 | } }, | |
2337 | .iif = loopback_dev.ifindex, | |
2338 | .oif = oldflp->oif }; | |
2339 | struct fib_result res; | |
2340 | unsigned flags = 0; | |
2341 | struct net_device *dev_out = NULL; | |
2342 | int free_res = 0; | |
2343 | int err; | |
2344 | ||
2345 | ||
2346 | res.fi = NULL; | |
2347 | #ifdef CONFIG_IP_MULTIPLE_TABLES | |
2348 | res.r = NULL; | |
2349 | #endif | |
2350 | ||
2351 | if (oldflp->fl4_src) { | |
2352 | err = -EINVAL; | |
2353 | if (MULTICAST(oldflp->fl4_src) || | |
2354 | BADCLASS(oldflp->fl4_src) || | |
2355 | ZERONET(oldflp->fl4_src)) | |
2356 | goto out; | |
2357 | ||
2358 | /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ | |
2359 | dev_out = ip_dev_find(oldflp->fl4_src); | |
2360 | if (dev_out == NULL) | |
2361 | goto out; | |
2362 | ||
2363 | /* I removed check for oif == dev_out->oif here. | |
2364 | It was wrong for two reasons: | |
2365 | 1. ip_dev_find(saddr) can return wrong iface, if saddr is | |
2366 | assigned to multiple interfaces. | |
2367 | 2. Moreover, we are allowed to send packets with saddr | |
2368 | of another iface. --ANK | |
2369 | */ | |
2370 | ||
2371 | if (oldflp->oif == 0 | |
2372 | && (MULTICAST(oldflp->fl4_dst) || oldflp->fl4_dst == 0xFFFFFFFF)) { | |
2373 | /* Special hack: user can direct multicasts | |
2374 | and limited broadcast via necessary interface | |
2375 | without fiddling with IP_MULTICAST_IF or IP_PKTINFO. | |
2376 | This hack is not just for fun, it allows | |
2377 | vic,vat and friends to work. | |
2378 | They bind socket to loopback, set ttl to zero | |
2379 | and expect that it will work. | |
2380 | From the viewpoint of routing cache they are broken, | |
2381 | because we are not allowed to build multicast path | |
2382 | with loopback source addr (look, routing cache | |
2383 | cannot know, that ttl is zero, so that packet | |
2384 | will not leave this host and route is valid). | |
2385 | Luckily, this hack is good workaround. | |
2386 | */ | |
2387 | ||
2388 | fl.oif = dev_out->ifindex; | |
2389 | goto make_route; | |
2390 | } | |
2391 | if (dev_out) | |
2392 | dev_put(dev_out); | |
2393 | dev_out = NULL; | |
2394 | } | |
2395 | ||
2396 | ||
2397 | if (oldflp->oif) { | |
2398 | dev_out = dev_get_by_index(oldflp->oif); | |
2399 | err = -ENODEV; | |
2400 | if (dev_out == NULL) | |
2401 | goto out; | |
2402 | if (__in_dev_get(dev_out) == NULL) { | |
2403 | dev_put(dev_out); | |
2404 | goto out; /* Wrong error code */ | |
2405 | } | |
2406 | ||
2407 | if (LOCAL_MCAST(oldflp->fl4_dst) || oldflp->fl4_dst == 0xFFFFFFFF) { | |
2408 | if (!fl.fl4_src) | |
2409 | fl.fl4_src = inet_select_addr(dev_out, 0, | |
2410 | RT_SCOPE_LINK); | |
2411 | goto make_route; | |
2412 | } | |
2413 | if (!fl.fl4_src) { | |
2414 | if (MULTICAST(oldflp->fl4_dst)) | |
2415 | fl.fl4_src = inet_select_addr(dev_out, 0, | |
2416 | fl.fl4_scope); | |
2417 | else if (!oldflp->fl4_dst) | |
2418 | fl.fl4_src = inet_select_addr(dev_out, 0, | |
2419 | RT_SCOPE_HOST); | |
2420 | } | |
2421 | } | |
2422 | ||
2423 | if (!fl.fl4_dst) { | |
2424 | fl.fl4_dst = fl.fl4_src; | |
2425 | if (!fl.fl4_dst) | |
2426 | fl.fl4_dst = fl.fl4_src = htonl(INADDR_LOOPBACK); | |
2427 | if (dev_out) | |
2428 | dev_put(dev_out); | |
2429 | dev_out = &loopback_dev; | |
2430 | dev_hold(dev_out); | |
2431 | fl.oif = loopback_dev.ifindex; | |
2432 | res.type = RTN_LOCAL; | |
2433 | flags |= RTCF_LOCAL; | |
2434 | goto make_route; | |
2435 | } | |
2436 | ||
2437 | if (fib_lookup(&fl, &res)) { | |
2438 | res.fi = NULL; | |
2439 | if (oldflp->oif) { | |
2440 | /* Apparently, routing tables are wrong. Assume, | |
2441 | that the destination is on link. | |
2442 | ||
2443 | WHY? DW. | |
2444 | Because we are allowed to send to iface | |
2445 | even if it has NO routes and NO assigned | |
2446 | addresses. When oif is specified, routing | |
2447 | tables are looked up with only one purpose: | |
2448 | to catch if destination is gatewayed, rather than | |
2449 | direct. Moreover, if MSG_DONTROUTE is set, | |
2450 | we send packet, ignoring both routing tables | |
2451 | and ifaddr state. --ANK | |
2452 | ||
2453 | ||
2454 | We could make it even if oif is unknown, | |
2455 | likely IPv6, but we do not. | |
2456 | */ | |
2457 | ||
2458 | if (fl.fl4_src == 0) | |
2459 | fl.fl4_src = inet_select_addr(dev_out, 0, | |
2460 | RT_SCOPE_LINK); | |
2461 | res.type = RTN_UNICAST; | |
2462 | goto make_route; | |
2463 | } | |
2464 | if (dev_out) | |
2465 | dev_put(dev_out); | |
2466 | err = -ENETUNREACH; | |
2467 | goto out; | |
2468 | } | |
2469 | free_res = 1; | |
2470 | ||
2471 | if (res.type == RTN_LOCAL) { | |
2472 | if (!fl.fl4_src) | |
2473 | fl.fl4_src = fl.fl4_dst; | |
2474 | if (dev_out) | |
2475 | dev_put(dev_out); | |
2476 | dev_out = &loopback_dev; | |
2477 | dev_hold(dev_out); | |
2478 | fl.oif = dev_out->ifindex; | |
2479 | if (res.fi) | |
2480 | fib_info_put(res.fi); | |
2481 | res.fi = NULL; | |
2482 | flags |= RTCF_LOCAL; | |
2483 | goto make_route; | |
2484 | } | |
2485 | ||
2486 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
2487 | if (res.fi->fib_nhs > 1 && fl.oif == 0) | |
2488 | fib_select_multipath(&fl, &res); | |
2489 | else | |
2490 | #endif | |
2491 | if (!res.prefixlen && res.type == RTN_UNICAST && !fl.oif) | |
2492 | fib_select_default(&fl, &res); | |
2493 | ||
2494 | if (!fl.fl4_src) | |
2495 | fl.fl4_src = FIB_RES_PREFSRC(res); | |
2496 | ||
2497 | if (dev_out) | |
2498 | dev_put(dev_out); | |
2499 | dev_out = FIB_RES_DEV(res); | |
2500 | dev_hold(dev_out); | |
2501 | fl.oif = dev_out->ifindex; | |
2502 | ||
2503 | ||
2504 | make_route: | |
2505 | err = ip_mkroute_output(rp, &res, &fl, oldflp, dev_out, flags); | |
2506 | ||
2507 | ||
2508 | if (free_res) | |
2509 | fib_res_put(&res); | |
2510 | if (dev_out) | |
2511 | dev_put(dev_out); | |
2512 | out: return err; | |
2513 | } | |
2514 | ||
2515 | int __ip_route_output_key(struct rtable **rp, const struct flowi *flp) | |
2516 | { | |
2517 | unsigned hash; | |
2518 | struct rtable *rth; | |
2519 | ||
2520 | hash = rt_hash_code(flp->fl4_dst, flp->fl4_src ^ (flp->oif << 5), flp->fl4_tos); | |
2521 | ||
2522 | rcu_read_lock_bh(); | |
2523 | for (rth = rcu_dereference(rt_hash_table[hash].chain); rth; | |
2524 | rth = rcu_dereference(rth->u.rt_next)) { | |
2525 | if (rth->fl.fl4_dst == flp->fl4_dst && | |
2526 | rth->fl.fl4_src == flp->fl4_src && | |
2527 | rth->fl.iif == 0 && | |
2528 | rth->fl.oif == flp->oif && | |
2529 | #ifdef CONFIG_IP_ROUTE_FWMARK | |
2530 | rth->fl.fl4_fwmark == flp->fl4_fwmark && | |
2531 | #endif | |
2532 | !((rth->fl.fl4_tos ^ flp->fl4_tos) & | |
2533 | (IPTOS_RT_MASK | RTO_ONLINK))) { | |
2534 | ||
2535 | /* check for multipath routes and choose one if | |
2536 | * necessary | |
2537 | */ | |
2538 | if (multipath_select_route(flp, rth, rp)) { | |
2539 | dst_hold(&(*rp)->u.dst); | |
2540 | RT_CACHE_STAT_INC(out_hit); | |
2541 | rcu_read_unlock_bh(); | |
2542 | return 0; | |
2543 | } | |
2544 | ||
2545 | rth->u.dst.lastuse = jiffies; | |
2546 | dst_hold(&rth->u.dst); | |
2547 | rth->u.dst.__use++; | |
2548 | RT_CACHE_STAT_INC(out_hit); | |
2549 | rcu_read_unlock_bh(); | |
2550 | *rp = rth; | |
2551 | return 0; | |
2552 | } | |
2553 | RT_CACHE_STAT_INC(out_hlist_search); | |
2554 | } | |
2555 | rcu_read_unlock_bh(); | |
2556 | ||
2557 | return ip_route_output_slow(rp, flp); | |
2558 | } | |
2559 | ||
2560 | int ip_route_output_flow(struct rtable **rp, struct flowi *flp, struct sock *sk, int flags) | |
2561 | { | |
2562 | int err; | |
2563 | ||
2564 | if ((err = __ip_route_output_key(rp, flp)) != 0) | |
2565 | return err; | |
2566 | ||
2567 | if (flp->proto) { | |
2568 | if (!flp->fl4_src) | |
2569 | flp->fl4_src = (*rp)->rt_src; | |
2570 | if (!flp->fl4_dst) | |
2571 | flp->fl4_dst = (*rp)->rt_dst; | |
2572 | return xfrm_lookup((struct dst_entry **)rp, flp, sk, flags); | |
2573 | } | |
2574 | ||
2575 | return 0; | |
2576 | } | |
2577 | ||
2578 | int ip_route_output_key(struct rtable **rp, struct flowi *flp) | |
2579 | { | |
2580 | return ip_route_output_flow(rp, flp, NULL, 0); | |
2581 | } | |
2582 | ||
2583 | static int rt_fill_info(struct sk_buff *skb, u32 pid, u32 seq, int event, | |
2584 | int nowait) | |
2585 | { | |
2586 | struct rtable *rt = (struct rtable*)skb->dst; | |
2587 | struct rtmsg *r; | |
2588 | struct nlmsghdr *nlh; | |
2589 | unsigned char *b = skb->tail; | |
2590 | struct rta_cacheinfo ci; | |
2591 | #ifdef CONFIG_IP_MROUTE | |
2592 | struct rtattr *eptr; | |
2593 | #endif | |
2594 | nlh = NLMSG_PUT(skb, pid, seq, event, sizeof(*r)); | |
2595 | r = NLMSG_DATA(nlh); | |
2596 | nlh->nlmsg_flags = (nowait && pid) ? NLM_F_MULTI : 0; | |
2597 | r->rtm_family = AF_INET; | |
2598 | r->rtm_dst_len = 32; | |
2599 | r->rtm_src_len = 0; | |
2600 | r->rtm_tos = rt->fl.fl4_tos; | |
2601 | r->rtm_table = RT_TABLE_MAIN; | |
2602 | r->rtm_type = rt->rt_type; | |
2603 | r->rtm_scope = RT_SCOPE_UNIVERSE; | |
2604 | r->rtm_protocol = RTPROT_UNSPEC; | |
2605 | r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED; | |
2606 | if (rt->rt_flags & RTCF_NOTIFY) | |
2607 | r->rtm_flags |= RTM_F_NOTIFY; | |
2608 | RTA_PUT(skb, RTA_DST, 4, &rt->rt_dst); | |
2609 | if (rt->fl.fl4_src) { | |
2610 | r->rtm_src_len = 32; | |
2611 | RTA_PUT(skb, RTA_SRC, 4, &rt->fl.fl4_src); | |
2612 | } | |
2613 | if (rt->u.dst.dev) | |
2614 | RTA_PUT(skb, RTA_OIF, sizeof(int), &rt->u.dst.dev->ifindex); | |
2615 | #ifdef CONFIG_NET_CLS_ROUTE | |
2616 | if (rt->u.dst.tclassid) | |
2617 | RTA_PUT(skb, RTA_FLOW, 4, &rt->u.dst.tclassid); | |
2618 | #endif | |
2619 | #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED | |
2620 | if (rt->rt_multipath_alg != IP_MP_ALG_NONE) { | |
2621 | __u32 alg = rt->rt_multipath_alg; | |
2622 | ||
2623 | RTA_PUT(skb, RTA_MP_ALGO, 4, &alg); | |
2624 | } | |
2625 | #endif | |
2626 | if (rt->fl.iif) | |
2627 | RTA_PUT(skb, RTA_PREFSRC, 4, &rt->rt_spec_dst); | |
2628 | else if (rt->rt_src != rt->fl.fl4_src) | |
2629 | RTA_PUT(skb, RTA_PREFSRC, 4, &rt->rt_src); | |
2630 | if (rt->rt_dst != rt->rt_gateway) | |
2631 | RTA_PUT(skb, RTA_GATEWAY, 4, &rt->rt_gateway); | |
2632 | if (rtnetlink_put_metrics(skb, rt->u.dst.metrics) < 0) | |
2633 | goto rtattr_failure; | |
2634 | ci.rta_lastuse = jiffies_to_clock_t(jiffies - rt->u.dst.lastuse); | |
2635 | ci.rta_used = rt->u.dst.__use; | |
2636 | ci.rta_clntref = atomic_read(&rt->u.dst.__refcnt); | |
2637 | if (rt->u.dst.expires) | |
2638 | ci.rta_expires = jiffies_to_clock_t(rt->u.dst.expires - jiffies); | |
2639 | else | |
2640 | ci.rta_expires = 0; | |
2641 | ci.rta_error = rt->u.dst.error; | |
2642 | ci.rta_id = ci.rta_ts = ci.rta_tsage = 0; | |
2643 | if (rt->peer) { | |
2644 | ci.rta_id = rt->peer->ip_id_count; | |
2645 | if (rt->peer->tcp_ts_stamp) { | |
2646 | ci.rta_ts = rt->peer->tcp_ts; | |
2647 | ci.rta_tsage = xtime.tv_sec - rt->peer->tcp_ts_stamp; | |
2648 | } | |
2649 | } | |
2650 | #ifdef CONFIG_IP_MROUTE | |
2651 | eptr = (struct rtattr*)skb->tail; | |
2652 | #endif | |
2653 | RTA_PUT(skb, RTA_CACHEINFO, sizeof(ci), &ci); | |
2654 | if (rt->fl.iif) { | |
2655 | #ifdef CONFIG_IP_MROUTE | |
2656 | u32 dst = rt->rt_dst; | |
2657 | ||
2658 | if (MULTICAST(dst) && !LOCAL_MCAST(dst) && | |
2659 | ipv4_devconf.mc_forwarding) { | |
2660 | int err = ipmr_get_route(skb, r, nowait); | |
2661 | if (err <= 0) { | |
2662 | if (!nowait) { | |
2663 | if (err == 0) | |
2664 | return 0; | |
2665 | goto nlmsg_failure; | |
2666 | } else { | |
2667 | if (err == -EMSGSIZE) | |
2668 | goto nlmsg_failure; | |
2669 | ((struct rta_cacheinfo*)RTA_DATA(eptr))->rta_error = err; | |
2670 | } | |
2671 | } | |
2672 | } else | |
2673 | #endif | |
2674 | RTA_PUT(skb, RTA_IIF, sizeof(int), &rt->fl.iif); | |
2675 | } | |
2676 | ||
2677 | nlh->nlmsg_len = skb->tail - b; | |
2678 | return skb->len; | |
2679 | ||
2680 | nlmsg_failure: | |
2681 | rtattr_failure: | |
2682 | skb_trim(skb, b - skb->data); | |
2683 | return -1; | |
2684 | } | |
2685 | ||
2686 | int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg) | |
2687 | { | |
2688 | struct rtattr **rta = arg; | |
2689 | struct rtmsg *rtm = NLMSG_DATA(nlh); | |
2690 | struct rtable *rt = NULL; | |
2691 | u32 dst = 0; | |
2692 | u32 src = 0; | |
2693 | int iif = 0; | |
2694 | int err = -ENOBUFS; | |
2695 | struct sk_buff *skb; | |
2696 | ||
2697 | skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); | |
2698 | if (!skb) | |
2699 | goto out; | |
2700 | ||
2701 | /* Reserve room for dummy headers, this skb can pass | |
2702 | through good chunk of routing engine. | |
2703 | */ | |
2704 | skb->mac.raw = skb->data; | |
2705 | skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr)); | |
2706 | ||
2707 | if (rta[RTA_SRC - 1]) | |
2708 | memcpy(&src, RTA_DATA(rta[RTA_SRC - 1]), 4); | |
2709 | if (rta[RTA_DST - 1]) | |
2710 | memcpy(&dst, RTA_DATA(rta[RTA_DST - 1]), 4); | |
2711 | if (rta[RTA_IIF - 1]) | |
2712 | memcpy(&iif, RTA_DATA(rta[RTA_IIF - 1]), sizeof(int)); | |
2713 | ||
2714 | if (iif) { | |
2715 | struct net_device *dev = __dev_get_by_index(iif); | |
2716 | err = -ENODEV; | |
2717 | if (!dev) | |
2718 | goto out_free; | |
2719 | skb->protocol = htons(ETH_P_IP); | |
2720 | skb->dev = dev; | |
2721 | local_bh_disable(); | |
2722 | err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev); | |
2723 | local_bh_enable(); | |
2724 | rt = (struct rtable*)skb->dst; | |
2725 | if (!err && rt->u.dst.error) | |
2726 | err = -rt->u.dst.error; | |
2727 | } else { | |
2728 | struct flowi fl = { .nl_u = { .ip4_u = { .daddr = dst, | |
2729 | .saddr = src, | |
2730 | .tos = rtm->rtm_tos } } }; | |
2731 | int oif = 0; | |
2732 | if (rta[RTA_OIF - 1]) | |
2733 | memcpy(&oif, RTA_DATA(rta[RTA_OIF - 1]), sizeof(int)); | |
2734 | fl.oif = oif; | |
2735 | err = ip_route_output_key(&rt, &fl); | |
2736 | } | |
2737 | if (err) | |
2738 | goto out_free; | |
2739 | ||
2740 | skb->dst = &rt->u.dst; | |
2741 | if (rtm->rtm_flags & RTM_F_NOTIFY) | |
2742 | rt->rt_flags |= RTCF_NOTIFY; | |
2743 | ||
2744 | NETLINK_CB(skb).dst_pid = NETLINK_CB(in_skb).pid; | |
2745 | ||
2746 | err = rt_fill_info(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, | |
2747 | RTM_NEWROUTE, 0); | |
2748 | if (!err) | |
2749 | goto out_free; | |
2750 | if (err < 0) { | |
2751 | err = -EMSGSIZE; | |
2752 | goto out_free; | |
2753 | } | |
2754 | ||
2755 | err = netlink_unicast(rtnl, skb, NETLINK_CB(in_skb).pid, MSG_DONTWAIT); | |
2756 | if (err > 0) | |
2757 | err = 0; | |
2758 | out: return err; | |
2759 | ||
2760 | out_free: | |
2761 | kfree_skb(skb); | |
2762 | goto out; | |
2763 | } | |
2764 | ||
2765 | int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb) | |
2766 | { | |
2767 | struct rtable *rt; | |
2768 | int h, s_h; | |
2769 | int idx, s_idx; | |
2770 | ||
2771 | s_h = cb->args[0]; | |
2772 | s_idx = idx = cb->args[1]; | |
2773 | for (h = 0; h <= rt_hash_mask; h++) { | |
2774 | if (h < s_h) continue; | |
2775 | if (h > s_h) | |
2776 | s_idx = 0; | |
2777 | rcu_read_lock_bh(); | |
2778 | for (rt = rcu_dereference(rt_hash_table[h].chain), idx = 0; rt; | |
2779 | rt = rcu_dereference(rt->u.rt_next), idx++) { | |
2780 | if (idx < s_idx) | |
2781 | continue; | |
2782 | skb->dst = dst_clone(&rt->u.dst); | |
2783 | if (rt_fill_info(skb, NETLINK_CB(cb->skb).pid, | |
2784 | cb->nlh->nlmsg_seq, | |
2785 | RTM_NEWROUTE, 1) <= 0) { | |
2786 | dst_release(xchg(&skb->dst, NULL)); | |
2787 | rcu_read_unlock_bh(); | |
2788 | goto done; | |
2789 | } | |
2790 | dst_release(xchg(&skb->dst, NULL)); | |
2791 | } | |
2792 | rcu_read_unlock_bh(); | |
2793 | } | |
2794 | ||
2795 | done: | |
2796 | cb->args[0] = h; | |
2797 | cb->args[1] = idx; | |
2798 | return skb->len; | |
2799 | } | |
2800 | ||
2801 | void ip_rt_multicast_event(struct in_device *in_dev) | |
2802 | { | |
2803 | rt_cache_flush(0); | |
2804 | } | |
2805 | ||
2806 | #ifdef CONFIG_SYSCTL | |
2807 | static int flush_delay; | |
2808 | ||
2809 | static int ipv4_sysctl_rtcache_flush(ctl_table *ctl, int write, | |
2810 | struct file *filp, void __user *buffer, | |
2811 | size_t *lenp, loff_t *ppos) | |
2812 | { | |
2813 | if (write) { | |
2814 | proc_dointvec(ctl, write, filp, buffer, lenp, ppos); | |
2815 | rt_cache_flush(flush_delay); | |
2816 | return 0; | |
2817 | } | |
2818 | ||
2819 | return -EINVAL; | |
2820 | } | |
2821 | ||
2822 | static int ipv4_sysctl_rtcache_flush_strategy(ctl_table *table, | |
2823 | int __user *name, | |
2824 | int nlen, | |
2825 | void __user *oldval, | |
2826 | size_t __user *oldlenp, | |
2827 | void __user *newval, | |
2828 | size_t newlen, | |
2829 | void **context) | |
2830 | { | |
2831 | int delay; | |
2832 | if (newlen != sizeof(int)) | |
2833 | return -EINVAL; | |
2834 | if (get_user(delay, (int __user *)newval)) | |
2835 | return -EFAULT; | |
2836 | rt_cache_flush(delay); | |
2837 | return 0; | |
2838 | } | |
2839 | ||
2840 | ctl_table ipv4_route_table[] = { | |
2841 | { | |
2842 | .ctl_name = NET_IPV4_ROUTE_FLUSH, | |
2843 | .procname = "flush", | |
2844 | .data = &flush_delay, | |
2845 | .maxlen = sizeof(int), | |
2846 | .mode = 0644, | |
2847 | .proc_handler = &ipv4_sysctl_rtcache_flush, | |
2848 | .strategy = &ipv4_sysctl_rtcache_flush_strategy, | |
2849 | }, | |
2850 | { | |
2851 | .ctl_name = NET_IPV4_ROUTE_MIN_DELAY, | |
2852 | .procname = "min_delay", | |
2853 | .data = &ip_rt_min_delay, | |
2854 | .maxlen = sizeof(int), | |
2855 | .mode = 0644, | |
2856 | .proc_handler = &proc_dointvec_jiffies, | |
2857 | .strategy = &sysctl_jiffies, | |
2858 | }, | |
2859 | { | |
2860 | .ctl_name = NET_IPV4_ROUTE_MAX_DELAY, | |
2861 | .procname = "max_delay", | |
2862 | .data = &ip_rt_max_delay, | |
2863 | .maxlen = sizeof(int), | |
2864 | .mode = 0644, | |
2865 | .proc_handler = &proc_dointvec_jiffies, | |
2866 | .strategy = &sysctl_jiffies, | |
2867 | }, | |
2868 | { | |
2869 | .ctl_name = NET_IPV4_ROUTE_GC_THRESH, | |
2870 | .procname = "gc_thresh", | |
2871 | .data = &ipv4_dst_ops.gc_thresh, | |
2872 | .maxlen = sizeof(int), | |
2873 | .mode = 0644, | |
2874 | .proc_handler = &proc_dointvec, | |
2875 | }, | |
2876 | { | |
2877 | .ctl_name = NET_IPV4_ROUTE_MAX_SIZE, | |
2878 | .procname = "max_size", | |
2879 | .data = &ip_rt_max_size, | |
2880 | .maxlen = sizeof(int), | |
2881 | .mode = 0644, | |
2882 | .proc_handler = &proc_dointvec, | |
2883 | }, | |
2884 | { | |
2885 | /* Deprecated. Use gc_min_interval_ms */ | |
2886 | ||
2887 | .ctl_name = NET_IPV4_ROUTE_GC_MIN_INTERVAL, | |
2888 | .procname = "gc_min_interval", | |
2889 | .data = &ip_rt_gc_min_interval, | |
2890 | .maxlen = sizeof(int), | |
2891 | .mode = 0644, | |
2892 | .proc_handler = &proc_dointvec_jiffies, | |
2893 | .strategy = &sysctl_jiffies, | |
2894 | }, | |
2895 | { | |
2896 | .ctl_name = NET_IPV4_ROUTE_GC_MIN_INTERVAL_MS, | |
2897 | .procname = "gc_min_interval_ms", | |
2898 | .data = &ip_rt_gc_min_interval, | |
2899 | .maxlen = sizeof(int), | |
2900 | .mode = 0644, | |
2901 | .proc_handler = &proc_dointvec_ms_jiffies, | |
2902 | .strategy = &sysctl_ms_jiffies, | |
2903 | }, | |
2904 | { | |
2905 | .ctl_name = NET_IPV4_ROUTE_GC_TIMEOUT, | |
2906 | .procname = "gc_timeout", | |
2907 | .data = &ip_rt_gc_timeout, | |
2908 | .maxlen = sizeof(int), | |
2909 | .mode = 0644, | |
2910 | .proc_handler = &proc_dointvec_jiffies, | |
2911 | .strategy = &sysctl_jiffies, | |
2912 | }, | |
2913 | { | |
2914 | .ctl_name = NET_IPV4_ROUTE_GC_INTERVAL, | |
2915 | .procname = "gc_interval", | |
2916 | .data = &ip_rt_gc_interval, | |
2917 | .maxlen = sizeof(int), | |
2918 | .mode = 0644, | |
2919 | .proc_handler = &proc_dointvec_jiffies, | |
2920 | .strategy = &sysctl_jiffies, | |
2921 | }, | |
2922 | { | |
2923 | .ctl_name = NET_IPV4_ROUTE_REDIRECT_LOAD, | |
2924 | .procname = "redirect_load", | |
2925 | .data = &ip_rt_redirect_load, | |
2926 | .maxlen = sizeof(int), | |
2927 | .mode = 0644, | |
2928 | .proc_handler = &proc_dointvec, | |
2929 | }, | |
2930 | { | |
2931 | .ctl_name = NET_IPV4_ROUTE_REDIRECT_NUMBER, | |
2932 | .procname = "redirect_number", | |
2933 | .data = &ip_rt_redirect_number, | |
2934 | .maxlen = sizeof(int), | |
2935 | .mode = 0644, | |
2936 | .proc_handler = &proc_dointvec, | |
2937 | }, | |
2938 | { | |
2939 | .ctl_name = NET_IPV4_ROUTE_REDIRECT_SILENCE, | |
2940 | .procname = "redirect_silence", | |
2941 | .data = &ip_rt_redirect_silence, | |
2942 | .maxlen = sizeof(int), | |
2943 | .mode = 0644, | |
2944 | .proc_handler = &proc_dointvec, | |
2945 | }, | |
2946 | { | |
2947 | .ctl_name = NET_IPV4_ROUTE_ERROR_COST, | |
2948 | .procname = "error_cost", | |
2949 | .data = &ip_rt_error_cost, | |
2950 | .maxlen = sizeof(int), | |
2951 | .mode = 0644, | |
2952 | .proc_handler = &proc_dointvec, | |
2953 | }, | |
2954 | { | |
2955 | .ctl_name = NET_IPV4_ROUTE_ERROR_BURST, | |
2956 | .procname = "error_burst", | |
2957 | .data = &ip_rt_error_burst, | |
2958 | .maxlen = sizeof(int), | |
2959 | .mode = 0644, | |
2960 | .proc_handler = &proc_dointvec, | |
2961 | }, | |
2962 | { | |
2963 | .ctl_name = NET_IPV4_ROUTE_GC_ELASTICITY, | |
2964 | .procname = "gc_elasticity", | |
2965 | .data = &ip_rt_gc_elasticity, | |
2966 | .maxlen = sizeof(int), | |
2967 | .mode = 0644, | |
2968 | .proc_handler = &proc_dointvec, | |
2969 | }, | |
2970 | { | |
2971 | .ctl_name = NET_IPV4_ROUTE_MTU_EXPIRES, | |
2972 | .procname = "mtu_expires", | |
2973 | .data = &ip_rt_mtu_expires, | |
2974 | .maxlen = sizeof(int), | |
2975 | .mode = 0644, | |
2976 | .proc_handler = &proc_dointvec_jiffies, | |
2977 | .strategy = &sysctl_jiffies, | |
2978 | }, | |
2979 | { | |
2980 | .ctl_name = NET_IPV4_ROUTE_MIN_PMTU, | |
2981 | .procname = "min_pmtu", | |
2982 | .data = &ip_rt_min_pmtu, | |
2983 | .maxlen = sizeof(int), | |
2984 | .mode = 0644, | |
2985 | .proc_handler = &proc_dointvec, | |
2986 | }, | |
2987 | { | |
2988 | .ctl_name = NET_IPV4_ROUTE_MIN_ADVMSS, | |
2989 | .procname = "min_adv_mss", | |
2990 | .data = &ip_rt_min_advmss, | |
2991 | .maxlen = sizeof(int), | |
2992 | .mode = 0644, | |
2993 | .proc_handler = &proc_dointvec, | |
2994 | }, | |
2995 | { | |
2996 | .ctl_name = NET_IPV4_ROUTE_SECRET_INTERVAL, | |
2997 | .procname = "secret_interval", | |
2998 | .data = &ip_rt_secret_interval, | |
2999 | .maxlen = sizeof(int), | |
3000 | .mode = 0644, | |
3001 | .proc_handler = &proc_dointvec_jiffies, | |
3002 | .strategy = &sysctl_jiffies, | |
3003 | }, | |
3004 | { .ctl_name = 0 } | |
3005 | }; | |
3006 | #endif | |
3007 | ||
3008 | #ifdef CONFIG_NET_CLS_ROUTE | |
3009 | struct ip_rt_acct *ip_rt_acct; | |
3010 | ||
3011 | /* This code sucks. But you should have seen it before! --RR */ | |
3012 | ||
3013 | /* IP route accounting ptr for this logical cpu number. */ | |
3014 | #define IP_RT_ACCT_CPU(i) (ip_rt_acct + i * 256) | |
3015 | ||
3016 | #ifdef CONFIG_PROC_FS | |
3017 | static int ip_rt_acct_read(char *buffer, char **start, off_t offset, | |
3018 | int length, int *eof, void *data) | |
3019 | { | |
3020 | unsigned int i; | |
3021 | ||
3022 | if ((offset & 3) || (length & 3)) | |
3023 | return -EIO; | |
3024 | ||
3025 | if (offset >= sizeof(struct ip_rt_acct) * 256) { | |
3026 | *eof = 1; | |
3027 | return 0; | |
3028 | } | |
3029 | ||
3030 | if (offset + length >= sizeof(struct ip_rt_acct) * 256) { | |
3031 | length = sizeof(struct ip_rt_acct) * 256 - offset; | |
3032 | *eof = 1; | |
3033 | } | |
3034 | ||
3035 | offset /= sizeof(u32); | |
3036 | ||
3037 | if (length > 0) { | |
3038 | u32 *src = ((u32 *) IP_RT_ACCT_CPU(0)) + offset; | |
3039 | u32 *dst = (u32 *) buffer; | |
3040 | ||
3041 | /* Copy first cpu. */ | |
3042 | *start = buffer; | |
3043 | memcpy(dst, src, length); | |
3044 | ||
3045 | /* Add the other cpus in, one int at a time */ | |
3046 | for_each_cpu(i) { | |
3047 | unsigned int j; | |
3048 | ||
3049 | src = ((u32 *) IP_RT_ACCT_CPU(i)) + offset; | |
3050 | ||
3051 | for (j = 0; j < length/4; j++) | |
3052 | dst[j] += src[j]; | |
3053 | } | |
3054 | } | |
3055 | return length; | |
3056 | } | |
3057 | #endif /* CONFIG_PROC_FS */ | |
3058 | #endif /* CONFIG_NET_CLS_ROUTE */ | |
3059 | ||
3060 | static __initdata unsigned long rhash_entries; | |
3061 | static int __init set_rhash_entries(char *str) | |
3062 | { | |
3063 | if (!str) | |
3064 | return 0; | |
3065 | rhash_entries = simple_strtoul(str, &str, 0); | |
3066 | return 1; | |
3067 | } | |
3068 | __setup("rhash_entries=", set_rhash_entries); | |
3069 | ||
3070 | int __init ip_rt_init(void) | |
3071 | { | |
3072 | int i, order, goal, rc = 0; | |
3073 | ||
3074 | rt_hash_rnd = (int) ((num_physpages ^ (num_physpages>>8)) ^ | |
3075 | (jiffies ^ (jiffies >> 7))); | |
3076 | ||
3077 | #ifdef CONFIG_NET_CLS_ROUTE | |
3078 | for (order = 0; | |
3079 | (PAGE_SIZE << order) < 256 * sizeof(struct ip_rt_acct) * NR_CPUS; order++) | |
3080 | /* NOTHING */; | |
3081 | ip_rt_acct = (struct ip_rt_acct *)__get_free_pages(GFP_KERNEL, order); | |
3082 | if (!ip_rt_acct) | |
3083 | panic("IP: failed to allocate ip_rt_acct\n"); | |
3084 | memset(ip_rt_acct, 0, PAGE_SIZE << order); | |
3085 | #endif | |
3086 | ||
3087 | ipv4_dst_ops.kmem_cachep = kmem_cache_create("ip_dst_cache", | |
3088 | sizeof(struct rtable), | |
3089 | 0, SLAB_HWCACHE_ALIGN, | |
3090 | NULL, NULL); | |
3091 | ||
3092 | if (!ipv4_dst_ops.kmem_cachep) | |
3093 | panic("IP: failed to allocate ip_dst_cache\n"); | |
3094 | ||
3095 | goal = num_physpages >> (26 - PAGE_SHIFT); | |
3096 | if (rhash_entries) | |
3097 | goal = (rhash_entries * sizeof(struct rt_hash_bucket)) >> PAGE_SHIFT; | |
3098 | for (order = 0; (1UL << order) < goal; order++) | |
3099 | /* NOTHING */; | |
3100 | ||
3101 | do { | |
3102 | rt_hash_mask = (1UL << order) * PAGE_SIZE / | |
3103 | sizeof(struct rt_hash_bucket); | |
3104 | while (rt_hash_mask & (rt_hash_mask - 1)) | |
3105 | rt_hash_mask--; | |
3106 | rt_hash_table = (struct rt_hash_bucket *) | |
3107 | __get_free_pages(GFP_ATOMIC, order); | |
3108 | } while (rt_hash_table == NULL && --order > 0); | |
3109 | ||
3110 | if (!rt_hash_table) | |
3111 | panic("Failed to allocate IP route cache hash table\n"); | |
3112 | ||
3113 | printk(KERN_INFO "IP: routing cache hash table of %u buckets, %ldKbytes\n", | |
3114 | rt_hash_mask, | |
3115 | (long) (rt_hash_mask * sizeof(struct rt_hash_bucket)) / 1024); | |
3116 | ||
3117 | for (rt_hash_log = 0; (1 << rt_hash_log) != rt_hash_mask; rt_hash_log++) | |
3118 | /* NOTHING */; | |
3119 | ||
3120 | rt_hash_mask--; | |
3121 | for (i = 0; i <= rt_hash_mask; i++) { | |
3122 | spin_lock_init(&rt_hash_table[i].lock); | |
3123 | rt_hash_table[i].chain = NULL; | |
3124 | } | |
3125 | ||
3126 | ipv4_dst_ops.gc_thresh = (rt_hash_mask + 1); | |
3127 | ip_rt_max_size = (rt_hash_mask + 1) * 16; | |
3128 | ||
3129 | rt_cache_stat = alloc_percpu(struct rt_cache_stat); | |
3130 | if (!rt_cache_stat) | |
3131 | return -ENOMEM; | |
3132 | ||
3133 | devinet_init(); | |
3134 | ip_fib_init(); | |
3135 | ||
3136 | init_timer(&rt_flush_timer); | |
3137 | rt_flush_timer.function = rt_run_flush; | |
3138 | init_timer(&rt_periodic_timer); | |
3139 | rt_periodic_timer.function = rt_check_expire; | |
3140 | init_timer(&rt_secret_timer); | |
3141 | rt_secret_timer.function = rt_secret_rebuild; | |
3142 | ||
3143 | /* All the timers, started at system startup tend | |
3144 | to synchronize. Perturb it a bit. | |
3145 | */ | |
3146 | rt_periodic_timer.expires = jiffies + net_random() % ip_rt_gc_interval + | |
3147 | ip_rt_gc_interval; | |
3148 | add_timer(&rt_periodic_timer); | |
3149 | ||
3150 | rt_secret_timer.expires = jiffies + net_random() % ip_rt_secret_interval + | |
3151 | ip_rt_secret_interval; | |
3152 | add_timer(&rt_secret_timer); | |
3153 | ||
3154 | #ifdef CONFIG_PROC_FS | |
3155 | { | |
3156 | struct proc_dir_entry *rtstat_pde = NULL; /* keep gcc happy */ | |
3157 | if (!proc_net_fops_create("rt_cache", S_IRUGO, &rt_cache_seq_fops) || | |
3158 | !(rtstat_pde = create_proc_entry("rt_cache", S_IRUGO, | |
3159 | proc_net_stat))) { | |
3160 | free_percpu(rt_cache_stat); | |
3161 | return -ENOMEM; | |
3162 | } | |
3163 | rtstat_pde->proc_fops = &rt_cpu_seq_fops; | |
3164 | } | |
3165 | #ifdef CONFIG_NET_CLS_ROUTE | |
3166 | create_proc_read_entry("rt_acct", 0, proc_net, ip_rt_acct_read, NULL); | |
3167 | #endif | |
3168 | #endif | |
3169 | #ifdef CONFIG_XFRM | |
3170 | xfrm_init(); | |
3171 | xfrm4_init(); | |
3172 | #endif | |
3173 | return rc; | |
3174 | } | |
3175 | ||
3176 | EXPORT_SYMBOL(__ip_select_ident); | |
3177 | EXPORT_SYMBOL(ip_route_input); | |
3178 | EXPORT_SYMBOL(ip_route_output_key); |