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1 | /* | |
2 | * INET An implementation of the TCP/IP protocol suite for the LINUX | |
3 | * operating system. INET is implemented using the BSD Socket | |
4 | * interface as the means of communication with the user level. | |
5 | * | |
6 | * ROUTE - implementation of the IP router. | |
7 | * | |
8 | * Authors: Ross Biro | |
9 | * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> | |
10 | * Alan Cox, <gw4pts@gw4pts.ampr.org> | |
11 | * Linus Torvalds, <Linus.Torvalds@helsinki.fi> | |
12 | * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> | |
13 | * | |
14 | * Fixes: | |
15 | * Alan Cox : Verify area fixes. | |
16 | * Alan Cox : cli() protects routing changes | |
17 | * Rui Oliveira : ICMP routing table updates | |
18 | * (rco@di.uminho.pt) Routing table insertion and update | |
19 | * Linus Torvalds : Rewrote bits to be sensible | |
20 | * Alan Cox : Added BSD route gw semantics | |
21 | * Alan Cox : Super /proc >4K | |
22 | * Alan Cox : MTU in route table | |
23 | * Alan Cox : MSS actually. Also added the window | |
24 | * clamper. | |
25 | * Sam Lantinga : Fixed route matching in rt_del() | |
26 | * Alan Cox : Routing cache support. | |
27 | * Alan Cox : Removed compatibility cruft. | |
28 | * Alan Cox : RTF_REJECT support. | |
29 | * Alan Cox : TCP irtt support. | |
30 | * Jonathan Naylor : Added Metric support. | |
31 | * Miquel van Smoorenburg : BSD API fixes. | |
32 | * Miquel van Smoorenburg : Metrics. | |
33 | * Alan Cox : Use __u32 properly | |
34 | * Alan Cox : Aligned routing errors more closely with BSD | |
35 | * our system is still very different. | |
36 | * Alan Cox : Faster /proc handling | |
37 | * Alexey Kuznetsov : Massive rework to support tree based routing, | |
38 | * routing caches and better behaviour. | |
39 | * | |
40 | * Olaf Erb : irtt wasn't being copied right. | |
41 | * Bjorn Ekwall : Kerneld route support. | |
42 | * Alan Cox : Multicast fixed (I hope) | |
43 | * Pavel Krauz : Limited broadcast fixed | |
44 | * Mike McLagan : Routing by source | |
45 | * Alexey Kuznetsov : End of old history. Split to fib.c and | |
46 | * route.c and rewritten from scratch. | |
47 | * Andi Kleen : Load-limit warning messages. | |
48 | * Vitaly E. Lavrov : Transparent proxy revived after year coma. | |
49 | * Vitaly E. Lavrov : Race condition in ip_route_input_slow. | |
50 | * Tobias Ringstrom : Uninitialized res.type in ip_route_output_slow. | |
51 | * Vladimir V. Ivanov : IP rule info (flowid) is really useful. | |
52 | * Marc Boucher : routing by fwmark | |
53 | * Robert Olsson : Added rt_cache statistics | |
54 | * Arnaldo C. Melo : Convert proc stuff to seq_file | |
55 | * Eric Dumazet : hashed spinlocks and rt_check_expire() fixes. | |
56 | * Ilia Sotnikov : Ignore TOS on PMTUD and Redirect | |
57 | * Ilia Sotnikov : Removed TOS from hash calculations | |
58 | * | |
59 | * This program is free software; you can redistribute it and/or | |
60 | * modify it under the terms of the GNU General Public License | |
61 | * as published by the Free Software Foundation; either version | |
62 | * 2 of the License, or (at your option) any later version. | |
63 | */ | |
64 | ||
65 | #include <linux/module.h> | |
66 | #include <asm/uaccess.h> | |
67 | #include <asm/system.h> | |
68 | #include <linux/bitops.h> | |
69 | #include <linux/types.h> | |
70 | #include <linux/kernel.h> | |
71 | #include <linux/mm.h> | |
72 | #include <linux/bootmem.h> | |
73 | #include <linux/string.h> | |
74 | #include <linux/socket.h> | |
75 | #include <linux/sockios.h> | |
76 | #include <linux/errno.h> | |
77 | #include <linux/in.h> | |
78 | #include <linux/inet.h> | |
79 | #include <linux/netdevice.h> | |
80 | #include <linux/proc_fs.h> | |
81 | #include <linux/init.h> | |
82 | #include <linux/workqueue.h> | |
83 | #include <linux/skbuff.h> | |
84 | #include <linux/inetdevice.h> | |
85 | #include <linux/igmp.h> | |
86 | #include <linux/pkt_sched.h> | |
87 | #include <linux/mroute.h> | |
88 | #include <linux/netfilter_ipv4.h> | |
89 | #include <linux/random.h> | |
90 | #include <linux/jhash.h> | |
91 | #include <linux/rcupdate.h> | |
92 | #include <linux/times.h> | |
93 | #include <linux/slab.h> | |
94 | #include <net/dst.h> | |
95 | #include <net/net_namespace.h> | |
96 | #include <net/protocol.h> | |
97 | #include <net/ip.h> | |
98 | #include <net/route.h> | |
99 | #include <net/inetpeer.h> | |
100 | #include <net/sock.h> | |
101 | #include <net/ip_fib.h> | |
102 | #include <net/arp.h> | |
103 | #include <net/tcp.h> | |
104 | #include <net/icmp.h> | |
105 | #include <net/xfrm.h> | |
106 | #include <net/netevent.h> | |
107 | #include <net/rtnetlink.h> | |
108 | #ifdef CONFIG_SYSCTL | |
109 | #include <linux/sysctl.h> | |
110 | #endif | |
111 | ||
112 | #define RT_FL_TOS(oldflp) \ | |
113 | ((u32)(oldflp->fl4_tos & (IPTOS_RT_MASK | RTO_ONLINK))) | |
114 | ||
115 | #define IP_MAX_MTU 0xFFF0 | |
116 | ||
117 | #define RT_GC_TIMEOUT (300*HZ) | |
118 | ||
119 | static int ip_rt_max_size; | |
120 | static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT; | |
121 | static int ip_rt_gc_interval __read_mostly = 60 * HZ; | |
122 | static int ip_rt_gc_min_interval __read_mostly = HZ / 2; | |
123 | static int ip_rt_redirect_number __read_mostly = 9; | |
124 | static int ip_rt_redirect_load __read_mostly = HZ / 50; | |
125 | static int ip_rt_redirect_silence __read_mostly = ((HZ / 50) << (9 + 1)); | |
126 | static int ip_rt_error_cost __read_mostly = HZ; | |
127 | static int ip_rt_error_burst __read_mostly = 5 * HZ; | |
128 | static int ip_rt_gc_elasticity __read_mostly = 8; | |
129 | static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ; | |
130 | static int ip_rt_min_pmtu __read_mostly = 512 + 20 + 20; | |
131 | static int ip_rt_min_advmss __read_mostly = 256; | |
132 | static int rt_chain_length_max __read_mostly = 20; | |
133 | ||
134 | static struct delayed_work expires_work; | |
135 | static unsigned long expires_ljiffies; | |
136 | ||
137 | /* | |
138 | * Interface to generic destination cache. | |
139 | */ | |
140 | ||
141 | static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie); | |
142 | static void ipv4_dst_destroy(struct dst_entry *dst); | |
143 | static void ipv4_dst_ifdown(struct dst_entry *dst, | |
144 | struct net_device *dev, int how); | |
145 | static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst); | |
146 | static void ipv4_link_failure(struct sk_buff *skb); | |
147 | static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu); | |
148 | static int rt_garbage_collect(struct dst_ops *ops); | |
149 | ||
150 | ||
151 | static struct dst_ops ipv4_dst_ops = { | |
152 | .family = AF_INET, | |
153 | .protocol = cpu_to_be16(ETH_P_IP), | |
154 | .gc = rt_garbage_collect, | |
155 | .check = ipv4_dst_check, | |
156 | .destroy = ipv4_dst_destroy, | |
157 | .ifdown = ipv4_dst_ifdown, | |
158 | .negative_advice = ipv4_negative_advice, | |
159 | .link_failure = ipv4_link_failure, | |
160 | .update_pmtu = ip_rt_update_pmtu, | |
161 | .local_out = __ip_local_out, | |
162 | }; | |
163 | ||
164 | #define ECN_OR_COST(class) TC_PRIO_##class | |
165 | ||
166 | const __u8 ip_tos2prio[16] = { | |
167 | TC_PRIO_BESTEFFORT, | |
168 | ECN_OR_COST(FILLER), | |
169 | TC_PRIO_BESTEFFORT, | |
170 | ECN_OR_COST(BESTEFFORT), | |
171 | TC_PRIO_BULK, | |
172 | ECN_OR_COST(BULK), | |
173 | TC_PRIO_BULK, | |
174 | ECN_OR_COST(BULK), | |
175 | TC_PRIO_INTERACTIVE, | |
176 | ECN_OR_COST(INTERACTIVE), | |
177 | TC_PRIO_INTERACTIVE, | |
178 | ECN_OR_COST(INTERACTIVE), | |
179 | TC_PRIO_INTERACTIVE_BULK, | |
180 | ECN_OR_COST(INTERACTIVE_BULK), | |
181 | TC_PRIO_INTERACTIVE_BULK, | |
182 | ECN_OR_COST(INTERACTIVE_BULK) | |
183 | }; | |
184 | ||
185 | ||
186 | /* | |
187 | * Route cache. | |
188 | */ | |
189 | ||
190 | /* The locking scheme is rather straight forward: | |
191 | * | |
192 | * 1) Read-Copy Update protects the buckets of the central route hash. | |
193 | * 2) Only writers remove entries, and they hold the lock | |
194 | * as they look at rtable reference counts. | |
195 | * 3) Only readers acquire references to rtable entries, | |
196 | * they do so with atomic increments and with the | |
197 | * lock held. | |
198 | */ | |
199 | ||
200 | struct rt_hash_bucket { | |
201 | struct rtable __rcu *chain; | |
202 | }; | |
203 | ||
204 | #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) || \ | |
205 | defined(CONFIG_PROVE_LOCKING) | |
206 | /* | |
207 | * Instead of using one spinlock for each rt_hash_bucket, we use a table of spinlocks | |
208 | * The size of this table is a power of two and depends on the number of CPUS. | |
209 | * (on lockdep we have a quite big spinlock_t, so keep the size down there) | |
210 | */ | |
211 | #ifdef CONFIG_LOCKDEP | |
212 | # define RT_HASH_LOCK_SZ 256 | |
213 | #else | |
214 | # if NR_CPUS >= 32 | |
215 | # define RT_HASH_LOCK_SZ 4096 | |
216 | # elif NR_CPUS >= 16 | |
217 | # define RT_HASH_LOCK_SZ 2048 | |
218 | # elif NR_CPUS >= 8 | |
219 | # define RT_HASH_LOCK_SZ 1024 | |
220 | # elif NR_CPUS >= 4 | |
221 | # define RT_HASH_LOCK_SZ 512 | |
222 | # else | |
223 | # define RT_HASH_LOCK_SZ 256 | |
224 | # endif | |
225 | #endif | |
226 | ||
227 | static spinlock_t *rt_hash_locks; | |
228 | # define rt_hash_lock_addr(slot) &rt_hash_locks[(slot) & (RT_HASH_LOCK_SZ - 1)] | |
229 | ||
230 | static __init void rt_hash_lock_init(void) | |
231 | { | |
232 | int i; | |
233 | ||
234 | rt_hash_locks = kmalloc(sizeof(spinlock_t) * RT_HASH_LOCK_SZ, | |
235 | GFP_KERNEL); | |
236 | if (!rt_hash_locks) | |
237 | panic("IP: failed to allocate rt_hash_locks\n"); | |
238 | ||
239 | for (i = 0; i < RT_HASH_LOCK_SZ; i++) | |
240 | spin_lock_init(&rt_hash_locks[i]); | |
241 | } | |
242 | #else | |
243 | # define rt_hash_lock_addr(slot) NULL | |
244 | ||
245 | static inline void rt_hash_lock_init(void) | |
246 | { | |
247 | } | |
248 | #endif | |
249 | ||
250 | static struct rt_hash_bucket *rt_hash_table __read_mostly; | |
251 | static unsigned rt_hash_mask __read_mostly; | |
252 | static unsigned int rt_hash_log __read_mostly; | |
253 | ||
254 | static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat); | |
255 | #define RT_CACHE_STAT_INC(field) __this_cpu_inc(rt_cache_stat.field) | |
256 | ||
257 | static inline unsigned int rt_hash(__be32 daddr, __be32 saddr, int idx, | |
258 | int genid) | |
259 | { | |
260 | return jhash_3words((__force u32)daddr, (__force u32)saddr, | |
261 | idx, genid) | |
262 | & rt_hash_mask; | |
263 | } | |
264 | ||
265 | static inline int rt_genid(struct net *net) | |
266 | { | |
267 | return atomic_read(&net->ipv4.rt_genid); | |
268 | } | |
269 | ||
270 | #ifdef CONFIG_PROC_FS | |
271 | struct rt_cache_iter_state { | |
272 | struct seq_net_private p; | |
273 | int bucket; | |
274 | int genid; | |
275 | }; | |
276 | ||
277 | static struct rtable *rt_cache_get_first(struct seq_file *seq) | |
278 | { | |
279 | struct rt_cache_iter_state *st = seq->private; | |
280 | struct rtable *r = NULL; | |
281 | ||
282 | for (st->bucket = rt_hash_mask; st->bucket >= 0; --st->bucket) { | |
283 | if (!rcu_dereference_raw(rt_hash_table[st->bucket].chain)) | |
284 | continue; | |
285 | rcu_read_lock_bh(); | |
286 | r = rcu_dereference_bh(rt_hash_table[st->bucket].chain); | |
287 | while (r) { | |
288 | if (dev_net(r->dst.dev) == seq_file_net(seq) && | |
289 | r->rt_genid == st->genid) | |
290 | return r; | |
291 | r = rcu_dereference_bh(r->dst.rt_next); | |
292 | } | |
293 | rcu_read_unlock_bh(); | |
294 | } | |
295 | return r; | |
296 | } | |
297 | ||
298 | static struct rtable *__rt_cache_get_next(struct seq_file *seq, | |
299 | struct rtable *r) | |
300 | { | |
301 | struct rt_cache_iter_state *st = seq->private; | |
302 | ||
303 | r = rcu_dereference_bh(r->dst.rt_next); | |
304 | while (!r) { | |
305 | rcu_read_unlock_bh(); | |
306 | do { | |
307 | if (--st->bucket < 0) | |
308 | return NULL; | |
309 | } while (!rcu_dereference_raw(rt_hash_table[st->bucket].chain)); | |
310 | rcu_read_lock_bh(); | |
311 | r = rcu_dereference_bh(rt_hash_table[st->bucket].chain); | |
312 | } | |
313 | return r; | |
314 | } | |
315 | ||
316 | static struct rtable *rt_cache_get_next(struct seq_file *seq, | |
317 | struct rtable *r) | |
318 | { | |
319 | struct rt_cache_iter_state *st = seq->private; | |
320 | while ((r = __rt_cache_get_next(seq, r)) != NULL) { | |
321 | if (dev_net(r->dst.dev) != seq_file_net(seq)) | |
322 | continue; | |
323 | if (r->rt_genid == st->genid) | |
324 | break; | |
325 | } | |
326 | return r; | |
327 | } | |
328 | ||
329 | static struct rtable *rt_cache_get_idx(struct seq_file *seq, loff_t pos) | |
330 | { | |
331 | struct rtable *r = rt_cache_get_first(seq); | |
332 | ||
333 | if (r) | |
334 | while (pos && (r = rt_cache_get_next(seq, r))) | |
335 | --pos; | |
336 | return pos ? NULL : r; | |
337 | } | |
338 | ||
339 | static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos) | |
340 | { | |
341 | struct rt_cache_iter_state *st = seq->private; | |
342 | if (*pos) | |
343 | return rt_cache_get_idx(seq, *pos - 1); | |
344 | st->genid = rt_genid(seq_file_net(seq)); | |
345 | return SEQ_START_TOKEN; | |
346 | } | |
347 | ||
348 | static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
349 | { | |
350 | struct rtable *r; | |
351 | ||
352 | if (v == SEQ_START_TOKEN) | |
353 | r = rt_cache_get_first(seq); | |
354 | else | |
355 | r = rt_cache_get_next(seq, v); | |
356 | ++*pos; | |
357 | return r; | |
358 | } | |
359 | ||
360 | static void rt_cache_seq_stop(struct seq_file *seq, void *v) | |
361 | { | |
362 | if (v && v != SEQ_START_TOKEN) | |
363 | rcu_read_unlock_bh(); | |
364 | } | |
365 | ||
366 | static int rt_cache_seq_show(struct seq_file *seq, void *v) | |
367 | { | |
368 | if (v == SEQ_START_TOKEN) | |
369 | seq_printf(seq, "%-127s\n", | |
370 | "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t" | |
371 | "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t" | |
372 | "HHUptod\tSpecDst"); | |
373 | else { | |
374 | struct rtable *r = v; | |
375 | int len; | |
376 | ||
377 | seq_printf(seq, "%s\t%08X\t%08X\t%8X\t%d\t%u\t%d\t" | |
378 | "%08X\t%d\t%u\t%u\t%02X\t%d\t%1d\t%08X%n", | |
379 | r->dst.dev ? r->dst.dev->name : "*", | |
380 | (__force u32)r->rt_dst, | |
381 | (__force u32)r->rt_gateway, | |
382 | r->rt_flags, atomic_read(&r->dst.__refcnt), | |
383 | r->dst.__use, 0, (__force u32)r->rt_src, | |
384 | (dst_metric(&r->dst, RTAX_ADVMSS) ? | |
385 | (int)dst_metric(&r->dst, RTAX_ADVMSS) + 40 : 0), | |
386 | dst_metric(&r->dst, RTAX_WINDOW), | |
387 | (int)((dst_metric(&r->dst, RTAX_RTT) >> 3) + | |
388 | dst_metric(&r->dst, RTAX_RTTVAR)), | |
389 | r->fl.fl4_tos, | |
390 | r->dst.hh ? atomic_read(&r->dst.hh->hh_refcnt) : -1, | |
391 | r->dst.hh ? (r->dst.hh->hh_output == | |
392 | dev_queue_xmit) : 0, | |
393 | r->rt_spec_dst, &len); | |
394 | ||
395 | seq_printf(seq, "%*s\n", 127 - len, ""); | |
396 | } | |
397 | return 0; | |
398 | } | |
399 | ||
400 | static const struct seq_operations rt_cache_seq_ops = { | |
401 | .start = rt_cache_seq_start, | |
402 | .next = rt_cache_seq_next, | |
403 | .stop = rt_cache_seq_stop, | |
404 | .show = rt_cache_seq_show, | |
405 | }; | |
406 | ||
407 | static int rt_cache_seq_open(struct inode *inode, struct file *file) | |
408 | { | |
409 | return seq_open_net(inode, file, &rt_cache_seq_ops, | |
410 | sizeof(struct rt_cache_iter_state)); | |
411 | } | |
412 | ||
413 | static const struct file_operations rt_cache_seq_fops = { | |
414 | .owner = THIS_MODULE, | |
415 | .open = rt_cache_seq_open, | |
416 | .read = seq_read, | |
417 | .llseek = seq_lseek, | |
418 | .release = seq_release_net, | |
419 | }; | |
420 | ||
421 | ||
422 | static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos) | |
423 | { | |
424 | int cpu; | |
425 | ||
426 | if (*pos == 0) | |
427 | return SEQ_START_TOKEN; | |
428 | ||
429 | for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) { | |
430 | if (!cpu_possible(cpu)) | |
431 | continue; | |
432 | *pos = cpu+1; | |
433 | return &per_cpu(rt_cache_stat, cpu); | |
434 | } | |
435 | return NULL; | |
436 | } | |
437 | ||
438 | static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
439 | { | |
440 | int cpu; | |
441 | ||
442 | for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) { | |
443 | if (!cpu_possible(cpu)) | |
444 | continue; | |
445 | *pos = cpu+1; | |
446 | return &per_cpu(rt_cache_stat, cpu); | |
447 | } | |
448 | return NULL; | |
449 | ||
450 | } | |
451 | ||
452 | static void rt_cpu_seq_stop(struct seq_file *seq, void *v) | |
453 | { | |
454 | ||
455 | } | |
456 | ||
457 | static int rt_cpu_seq_show(struct seq_file *seq, void *v) | |
458 | { | |
459 | struct rt_cache_stat *st = v; | |
460 | ||
461 | if (v == SEQ_START_TOKEN) { | |
462 | seq_printf(seq, "entries in_hit in_slow_tot in_slow_mc in_no_route in_brd in_martian_dst in_martian_src out_hit out_slow_tot out_slow_mc gc_total gc_ignored gc_goal_miss gc_dst_overflow in_hlist_search out_hlist_search\n"); | |
463 | return 0; | |
464 | } | |
465 | ||
466 | seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x " | |
467 | " %08x %08x %08x %08x %08x %08x %08x %08x %08x \n", | |
468 | dst_entries_get_slow(&ipv4_dst_ops), | |
469 | st->in_hit, | |
470 | st->in_slow_tot, | |
471 | st->in_slow_mc, | |
472 | st->in_no_route, | |
473 | st->in_brd, | |
474 | st->in_martian_dst, | |
475 | st->in_martian_src, | |
476 | ||
477 | st->out_hit, | |
478 | st->out_slow_tot, | |
479 | st->out_slow_mc, | |
480 | ||
481 | st->gc_total, | |
482 | st->gc_ignored, | |
483 | st->gc_goal_miss, | |
484 | st->gc_dst_overflow, | |
485 | st->in_hlist_search, | |
486 | st->out_hlist_search | |
487 | ); | |
488 | return 0; | |
489 | } | |
490 | ||
491 | static const struct seq_operations rt_cpu_seq_ops = { | |
492 | .start = rt_cpu_seq_start, | |
493 | .next = rt_cpu_seq_next, | |
494 | .stop = rt_cpu_seq_stop, | |
495 | .show = rt_cpu_seq_show, | |
496 | }; | |
497 | ||
498 | ||
499 | static int rt_cpu_seq_open(struct inode *inode, struct file *file) | |
500 | { | |
501 | return seq_open(file, &rt_cpu_seq_ops); | |
502 | } | |
503 | ||
504 | static const struct file_operations rt_cpu_seq_fops = { | |
505 | .owner = THIS_MODULE, | |
506 | .open = rt_cpu_seq_open, | |
507 | .read = seq_read, | |
508 | .llseek = seq_lseek, | |
509 | .release = seq_release, | |
510 | }; | |
511 | ||
512 | #ifdef CONFIG_NET_CLS_ROUTE | |
513 | static int rt_acct_proc_show(struct seq_file *m, void *v) | |
514 | { | |
515 | struct ip_rt_acct *dst, *src; | |
516 | unsigned int i, j; | |
517 | ||
518 | dst = kcalloc(256, sizeof(struct ip_rt_acct), GFP_KERNEL); | |
519 | if (!dst) | |
520 | return -ENOMEM; | |
521 | ||
522 | for_each_possible_cpu(i) { | |
523 | src = (struct ip_rt_acct *)per_cpu_ptr(ip_rt_acct, i); | |
524 | for (j = 0; j < 256; j++) { | |
525 | dst[j].o_bytes += src[j].o_bytes; | |
526 | dst[j].o_packets += src[j].o_packets; | |
527 | dst[j].i_bytes += src[j].i_bytes; | |
528 | dst[j].i_packets += src[j].i_packets; | |
529 | } | |
530 | } | |
531 | ||
532 | seq_write(m, dst, 256 * sizeof(struct ip_rt_acct)); | |
533 | kfree(dst); | |
534 | return 0; | |
535 | } | |
536 | ||
537 | static int rt_acct_proc_open(struct inode *inode, struct file *file) | |
538 | { | |
539 | return single_open(file, rt_acct_proc_show, NULL); | |
540 | } | |
541 | ||
542 | static const struct file_operations rt_acct_proc_fops = { | |
543 | .owner = THIS_MODULE, | |
544 | .open = rt_acct_proc_open, | |
545 | .read = seq_read, | |
546 | .llseek = seq_lseek, | |
547 | .release = single_release, | |
548 | }; | |
549 | #endif | |
550 | ||
551 | static int __net_init ip_rt_do_proc_init(struct net *net) | |
552 | { | |
553 | struct proc_dir_entry *pde; | |
554 | ||
555 | pde = proc_net_fops_create(net, "rt_cache", S_IRUGO, | |
556 | &rt_cache_seq_fops); | |
557 | if (!pde) | |
558 | goto err1; | |
559 | ||
560 | pde = proc_create("rt_cache", S_IRUGO, | |
561 | net->proc_net_stat, &rt_cpu_seq_fops); | |
562 | if (!pde) | |
563 | goto err2; | |
564 | ||
565 | #ifdef CONFIG_NET_CLS_ROUTE | |
566 | pde = proc_create("rt_acct", 0, net->proc_net, &rt_acct_proc_fops); | |
567 | if (!pde) | |
568 | goto err3; | |
569 | #endif | |
570 | return 0; | |
571 | ||
572 | #ifdef CONFIG_NET_CLS_ROUTE | |
573 | err3: | |
574 | remove_proc_entry("rt_cache", net->proc_net_stat); | |
575 | #endif | |
576 | err2: | |
577 | remove_proc_entry("rt_cache", net->proc_net); | |
578 | err1: | |
579 | return -ENOMEM; | |
580 | } | |
581 | ||
582 | static void __net_exit ip_rt_do_proc_exit(struct net *net) | |
583 | { | |
584 | remove_proc_entry("rt_cache", net->proc_net_stat); | |
585 | remove_proc_entry("rt_cache", net->proc_net); | |
586 | #ifdef CONFIG_NET_CLS_ROUTE | |
587 | remove_proc_entry("rt_acct", net->proc_net); | |
588 | #endif | |
589 | } | |
590 | ||
591 | static struct pernet_operations ip_rt_proc_ops __net_initdata = { | |
592 | .init = ip_rt_do_proc_init, | |
593 | .exit = ip_rt_do_proc_exit, | |
594 | }; | |
595 | ||
596 | static int __init ip_rt_proc_init(void) | |
597 | { | |
598 | return register_pernet_subsys(&ip_rt_proc_ops); | |
599 | } | |
600 | ||
601 | #else | |
602 | static inline int ip_rt_proc_init(void) | |
603 | { | |
604 | return 0; | |
605 | } | |
606 | #endif /* CONFIG_PROC_FS */ | |
607 | ||
608 | static inline void rt_free(struct rtable *rt) | |
609 | { | |
610 | call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free); | |
611 | } | |
612 | ||
613 | static inline void rt_drop(struct rtable *rt) | |
614 | { | |
615 | ip_rt_put(rt); | |
616 | call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free); | |
617 | } | |
618 | ||
619 | static inline int rt_fast_clean(struct rtable *rth) | |
620 | { | |
621 | /* Kill broadcast/multicast entries very aggresively, if they | |
622 | collide in hash table with more useful entries */ | |
623 | return (rth->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) && | |
624 | rth->fl.iif && rth->dst.rt_next; | |
625 | } | |
626 | ||
627 | static inline int rt_valuable(struct rtable *rth) | |
628 | { | |
629 | return (rth->rt_flags & (RTCF_REDIRECTED | RTCF_NOTIFY)) || | |
630 | rth->dst.expires; | |
631 | } | |
632 | ||
633 | static int rt_may_expire(struct rtable *rth, unsigned long tmo1, unsigned long tmo2) | |
634 | { | |
635 | unsigned long age; | |
636 | int ret = 0; | |
637 | ||
638 | if (atomic_read(&rth->dst.__refcnt)) | |
639 | goto out; | |
640 | ||
641 | ret = 1; | |
642 | if (rth->dst.expires && | |
643 | time_after_eq(jiffies, rth->dst.expires)) | |
644 | goto out; | |
645 | ||
646 | age = jiffies - rth->dst.lastuse; | |
647 | ret = 0; | |
648 | if ((age <= tmo1 && !rt_fast_clean(rth)) || | |
649 | (age <= tmo2 && rt_valuable(rth))) | |
650 | goto out; | |
651 | ret = 1; | |
652 | out: return ret; | |
653 | } | |
654 | ||
655 | /* Bits of score are: | |
656 | * 31: very valuable | |
657 | * 30: not quite useless | |
658 | * 29..0: usage counter | |
659 | */ | |
660 | static inline u32 rt_score(struct rtable *rt) | |
661 | { | |
662 | u32 score = jiffies - rt->dst.lastuse; | |
663 | ||
664 | score = ~score & ~(3<<30); | |
665 | ||
666 | if (rt_valuable(rt)) | |
667 | score |= (1<<31); | |
668 | ||
669 | if (!rt->fl.iif || | |
670 | !(rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST|RTCF_LOCAL))) | |
671 | score |= (1<<30); | |
672 | ||
673 | return score; | |
674 | } | |
675 | ||
676 | static inline bool rt_caching(const struct net *net) | |
677 | { | |
678 | return net->ipv4.current_rt_cache_rebuild_count <= | |
679 | net->ipv4.sysctl_rt_cache_rebuild_count; | |
680 | } | |
681 | ||
682 | static inline bool compare_hash_inputs(const struct flowi *fl1, | |
683 | const struct flowi *fl2) | |
684 | { | |
685 | return ((((__force u32)fl1->nl_u.ip4_u.daddr ^ (__force u32)fl2->nl_u.ip4_u.daddr) | | |
686 | ((__force u32)fl1->nl_u.ip4_u.saddr ^ (__force u32)fl2->nl_u.ip4_u.saddr) | | |
687 | (fl1->iif ^ fl2->iif)) == 0); | |
688 | } | |
689 | ||
690 | static inline int compare_keys(struct flowi *fl1, struct flowi *fl2) | |
691 | { | |
692 | return (((__force u32)fl1->nl_u.ip4_u.daddr ^ (__force u32)fl2->nl_u.ip4_u.daddr) | | |
693 | ((__force u32)fl1->nl_u.ip4_u.saddr ^ (__force u32)fl2->nl_u.ip4_u.saddr) | | |
694 | (fl1->mark ^ fl2->mark) | | |
695 | (*(u16 *)&fl1->nl_u.ip4_u.tos ^ *(u16 *)&fl2->nl_u.ip4_u.tos) | | |
696 | (fl1->oif ^ fl2->oif) | | |
697 | (fl1->iif ^ fl2->iif)) == 0; | |
698 | } | |
699 | ||
700 | static inline int compare_netns(struct rtable *rt1, struct rtable *rt2) | |
701 | { | |
702 | return net_eq(dev_net(rt1->dst.dev), dev_net(rt2->dst.dev)); | |
703 | } | |
704 | ||
705 | static inline int rt_is_expired(struct rtable *rth) | |
706 | { | |
707 | return rth->rt_genid != rt_genid(dev_net(rth->dst.dev)); | |
708 | } | |
709 | ||
710 | /* | |
711 | * Perform a full scan of hash table and free all entries. | |
712 | * Can be called by a softirq or a process. | |
713 | * In the later case, we want to be reschedule if necessary | |
714 | */ | |
715 | static void rt_do_flush(int process_context) | |
716 | { | |
717 | unsigned int i; | |
718 | struct rtable *rth, *next; | |
719 | struct rtable * tail; | |
720 | ||
721 | for (i = 0; i <= rt_hash_mask; i++) { | |
722 | if (process_context && need_resched()) | |
723 | cond_resched(); | |
724 | rth = rcu_dereference_raw(rt_hash_table[i].chain); | |
725 | if (!rth) | |
726 | continue; | |
727 | ||
728 | spin_lock_bh(rt_hash_lock_addr(i)); | |
729 | #ifdef CONFIG_NET_NS | |
730 | { | |
731 | struct rtable __rcu **prev; | |
732 | struct rtable *p; | |
733 | ||
734 | rth = rcu_dereference_protected(rt_hash_table[i].chain, | |
735 | lockdep_is_held(rt_hash_lock_addr(i))); | |
736 | ||
737 | /* defer releasing the head of the list after spin_unlock */ | |
738 | for (tail = rth; tail; | |
739 | tail = rcu_dereference_protected(tail->dst.rt_next, | |
740 | lockdep_is_held(rt_hash_lock_addr(i)))) | |
741 | if (!rt_is_expired(tail)) | |
742 | break; | |
743 | if (rth != tail) | |
744 | rt_hash_table[i].chain = tail; | |
745 | ||
746 | /* call rt_free on entries after the tail requiring flush */ | |
747 | prev = &rt_hash_table[i].chain; | |
748 | for (p = rcu_dereference_protected(*prev, | |
749 | lockdep_is_held(rt_hash_lock_addr(i))); | |
750 | p != NULL; | |
751 | p = next) { | |
752 | next = rcu_dereference_protected(p->dst.rt_next, | |
753 | lockdep_is_held(rt_hash_lock_addr(i))); | |
754 | if (!rt_is_expired(p)) { | |
755 | prev = &p->dst.rt_next; | |
756 | } else { | |
757 | *prev = next; | |
758 | rt_free(p); | |
759 | } | |
760 | } | |
761 | } | |
762 | #else | |
763 | rth = rcu_dereference_protected(rt_hash_table[i].chain, | |
764 | lockdep_is_held(rt_hash_lock_addr(i))); | |
765 | rcu_assign_pointer(rt_hash_table[i].chain, NULL); | |
766 | tail = NULL; | |
767 | #endif | |
768 | spin_unlock_bh(rt_hash_lock_addr(i)); | |
769 | ||
770 | for (; rth != tail; rth = next) { | |
771 | next = rcu_dereference_protected(rth->dst.rt_next, 1); | |
772 | rt_free(rth); | |
773 | } | |
774 | } | |
775 | } | |
776 | ||
777 | /* | |
778 | * While freeing expired entries, we compute average chain length | |
779 | * and standard deviation, using fixed-point arithmetic. | |
780 | * This to have an estimation of rt_chain_length_max | |
781 | * rt_chain_length_max = max(elasticity, AVG + 4*SD) | |
782 | * We use 3 bits for frational part, and 29 (or 61) for magnitude. | |
783 | */ | |
784 | ||
785 | #define FRACT_BITS 3 | |
786 | #define ONE (1UL << FRACT_BITS) | |
787 | ||
788 | /* | |
789 | * Given a hash chain and an item in this hash chain, | |
790 | * find if a previous entry has the same hash_inputs | |
791 | * (but differs on tos, mark or oif) | |
792 | * Returns 0 if an alias is found. | |
793 | * Returns ONE if rth has no alias before itself. | |
794 | */ | |
795 | static int has_noalias(const struct rtable *head, const struct rtable *rth) | |
796 | { | |
797 | const struct rtable *aux = head; | |
798 | ||
799 | while (aux != rth) { | |
800 | if (compare_hash_inputs(&aux->fl, &rth->fl)) | |
801 | return 0; | |
802 | aux = rcu_dereference_protected(aux->dst.rt_next, 1); | |
803 | } | |
804 | return ONE; | |
805 | } | |
806 | ||
807 | static void rt_check_expire(void) | |
808 | { | |
809 | static unsigned int rover; | |
810 | unsigned int i = rover, goal; | |
811 | struct rtable *rth; | |
812 | struct rtable __rcu **rthp; | |
813 | unsigned long samples = 0; | |
814 | unsigned long sum = 0, sum2 = 0; | |
815 | unsigned long delta; | |
816 | u64 mult; | |
817 | ||
818 | delta = jiffies - expires_ljiffies; | |
819 | expires_ljiffies = jiffies; | |
820 | mult = ((u64)delta) << rt_hash_log; | |
821 | if (ip_rt_gc_timeout > 1) | |
822 | do_div(mult, ip_rt_gc_timeout); | |
823 | goal = (unsigned int)mult; | |
824 | if (goal > rt_hash_mask) | |
825 | goal = rt_hash_mask + 1; | |
826 | for (; goal > 0; goal--) { | |
827 | unsigned long tmo = ip_rt_gc_timeout; | |
828 | unsigned long length; | |
829 | ||
830 | i = (i + 1) & rt_hash_mask; | |
831 | rthp = &rt_hash_table[i].chain; | |
832 | ||
833 | if (need_resched()) | |
834 | cond_resched(); | |
835 | ||
836 | samples++; | |
837 | ||
838 | if (rcu_dereference_raw(*rthp) == NULL) | |
839 | continue; | |
840 | length = 0; | |
841 | spin_lock_bh(rt_hash_lock_addr(i)); | |
842 | while ((rth = rcu_dereference_protected(*rthp, | |
843 | lockdep_is_held(rt_hash_lock_addr(i)))) != NULL) { | |
844 | prefetch(rth->dst.rt_next); | |
845 | if (rt_is_expired(rth)) { | |
846 | *rthp = rth->dst.rt_next; | |
847 | rt_free(rth); | |
848 | continue; | |
849 | } | |
850 | if (rth->dst.expires) { | |
851 | /* Entry is expired even if it is in use */ | |
852 | if (time_before_eq(jiffies, rth->dst.expires)) { | |
853 | nofree: | |
854 | tmo >>= 1; | |
855 | rthp = &rth->dst.rt_next; | |
856 | /* | |
857 | * We only count entries on | |
858 | * a chain with equal hash inputs once | |
859 | * so that entries for different QOS | |
860 | * levels, and other non-hash input | |
861 | * attributes don't unfairly skew | |
862 | * the length computation | |
863 | */ | |
864 | length += has_noalias(rt_hash_table[i].chain, rth); | |
865 | continue; | |
866 | } | |
867 | } else if (!rt_may_expire(rth, tmo, ip_rt_gc_timeout)) | |
868 | goto nofree; | |
869 | ||
870 | /* Cleanup aged off entries. */ | |
871 | *rthp = rth->dst.rt_next; | |
872 | rt_free(rth); | |
873 | } | |
874 | spin_unlock_bh(rt_hash_lock_addr(i)); | |
875 | sum += length; | |
876 | sum2 += length*length; | |
877 | } | |
878 | if (samples) { | |
879 | unsigned long avg = sum / samples; | |
880 | unsigned long sd = int_sqrt(sum2 / samples - avg*avg); | |
881 | rt_chain_length_max = max_t(unsigned long, | |
882 | ip_rt_gc_elasticity, | |
883 | (avg + 4*sd) >> FRACT_BITS); | |
884 | } | |
885 | rover = i; | |
886 | } | |
887 | ||
888 | /* | |
889 | * rt_worker_func() is run in process context. | |
890 | * we call rt_check_expire() to scan part of the hash table | |
891 | */ | |
892 | static void rt_worker_func(struct work_struct *work) | |
893 | { | |
894 | rt_check_expire(); | |
895 | schedule_delayed_work(&expires_work, ip_rt_gc_interval); | |
896 | } | |
897 | ||
898 | /* | |
899 | * Pertubation of rt_genid by a small quantity [1..256] | |
900 | * Using 8 bits of shuffling ensure we can call rt_cache_invalidate() | |
901 | * many times (2^24) without giving recent rt_genid. | |
902 | * Jenkins hash is strong enough that litle changes of rt_genid are OK. | |
903 | */ | |
904 | static void rt_cache_invalidate(struct net *net) | |
905 | { | |
906 | unsigned char shuffle; | |
907 | ||
908 | get_random_bytes(&shuffle, sizeof(shuffle)); | |
909 | atomic_add(shuffle + 1U, &net->ipv4.rt_genid); | |
910 | } | |
911 | ||
912 | /* | |
913 | * delay < 0 : invalidate cache (fast : entries will be deleted later) | |
914 | * delay >= 0 : invalidate & flush cache (can be long) | |
915 | */ | |
916 | void rt_cache_flush(struct net *net, int delay) | |
917 | { | |
918 | rt_cache_invalidate(net); | |
919 | if (delay >= 0) | |
920 | rt_do_flush(!in_softirq()); | |
921 | } | |
922 | ||
923 | /* Flush previous cache invalidated entries from the cache */ | |
924 | void rt_cache_flush_batch(void) | |
925 | { | |
926 | rt_do_flush(!in_softirq()); | |
927 | } | |
928 | ||
929 | static void rt_emergency_hash_rebuild(struct net *net) | |
930 | { | |
931 | if (net_ratelimit()) | |
932 | printk(KERN_WARNING "Route hash chain too long!\n"); | |
933 | rt_cache_invalidate(net); | |
934 | } | |
935 | ||
936 | /* | |
937 | Short description of GC goals. | |
938 | ||
939 | We want to build algorithm, which will keep routing cache | |
940 | at some equilibrium point, when number of aged off entries | |
941 | is kept approximately equal to newly generated ones. | |
942 | ||
943 | Current expiration strength is variable "expire". | |
944 | We try to adjust it dynamically, so that if networking | |
945 | is idle expires is large enough to keep enough of warm entries, | |
946 | and when load increases it reduces to limit cache size. | |
947 | */ | |
948 | ||
949 | static int rt_garbage_collect(struct dst_ops *ops) | |
950 | { | |
951 | static unsigned long expire = RT_GC_TIMEOUT; | |
952 | static unsigned long last_gc; | |
953 | static int rover; | |
954 | static int equilibrium; | |
955 | struct rtable *rth; | |
956 | struct rtable __rcu **rthp; | |
957 | unsigned long now = jiffies; | |
958 | int goal; | |
959 | int entries = dst_entries_get_fast(&ipv4_dst_ops); | |
960 | ||
961 | /* | |
962 | * Garbage collection is pretty expensive, | |
963 | * do not make it too frequently. | |
964 | */ | |
965 | ||
966 | RT_CACHE_STAT_INC(gc_total); | |
967 | ||
968 | if (now - last_gc < ip_rt_gc_min_interval && | |
969 | entries < ip_rt_max_size) { | |
970 | RT_CACHE_STAT_INC(gc_ignored); | |
971 | goto out; | |
972 | } | |
973 | ||
974 | entries = dst_entries_get_slow(&ipv4_dst_ops); | |
975 | /* Calculate number of entries, which we want to expire now. */ | |
976 | goal = entries - (ip_rt_gc_elasticity << rt_hash_log); | |
977 | if (goal <= 0) { | |
978 | if (equilibrium < ipv4_dst_ops.gc_thresh) | |
979 | equilibrium = ipv4_dst_ops.gc_thresh; | |
980 | goal = entries - equilibrium; | |
981 | if (goal > 0) { | |
982 | equilibrium += min_t(unsigned int, goal >> 1, rt_hash_mask + 1); | |
983 | goal = entries - equilibrium; | |
984 | } | |
985 | } else { | |
986 | /* We are in dangerous area. Try to reduce cache really | |
987 | * aggressively. | |
988 | */ | |
989 | goal = max_t(unsigned int, goal >> 1, rt_hash_mask + 1); | |
990 | equilibrium = entries - goal; | |
991 | } | |
992 | ||
993 | if (now - last_gc >= ip_rt_gc_min_interval) | |
994 | last_gc = now; | |
995 | ||
996 | if (goal <= 0) { | |
997 | equilibrium += goal; | |
998 | goto work_done; | |
999 | } | |
1000 | ||
1001 | do { | |
1002 | int i, k; | |
1003 | ||
1004 | for (i = rt_hash_mask, k = rover; i >= 0; i--) { | |
1005 | unsigned long tmo = expire; | |
1006 | ||
1007 | k = (k + 1) & rt_hash_mask; | |
1008 | rthp = &rt_hash_table[k].chain; | |
1009 | spin_lock_bh(rt_hash_lock_addr(k)); | |
1010 | while ((rth = rcu_dereference_protected(*rthp, | |
1011 | lockdep_is_held(rt_hash_lock_addr(k)))) != NULL) { | |
1012 | if (!rt_is_expired(rth) && | |
1013 | !rt_may_expire(rth, tmo, expire)) { | |
1014 | tmo >>= 1; | |
1015 | rthp = &rth->dst.rt_next; | |
1016 | continue; | |
1017 | } | |
1018 | *rthp = rth->dst.rt_next; | |
1019 | rt_free(rth); | |
1020 | goal--; | |
1021 | } | |
1022 | spin_unlock_bh(rt_hash_lock_addr(k)); | |
1023 | if (goal <= 0) | |
1024 | break; | |
1025 | } | |
1026 | rover = k; | |
1027 | ||
1028 | if (goal <= 0) | |
1029 | goto work_done; | |
1030 | ||
1031 | /* Goal is not achieved. We stop process if: | |
1032 | ||
1033 | - if expire reduced to zero. Otherwise, expire is halfed. | |
1034 | - if table is not full. | |
1035 | - if we are called from interrupt. | |
1036 | - jiffies check is just fallback/debug loop breaker. | |
1037 | We will not spin here for long time in any case. | |
1038 | */ | |
1039 | ||
1040 | RT_CACHE_STAT_INC(gc_goal_miss); | |
1041 | ||
1042 | if (expire == 0) | |
1043 | break; | |
1044 | ||
1045 | expire >>= 1; | |
1046 | #if RT_CACHE_DEBUG >= 2 | |
1047 | printk(KERN_DEBUG "expire>> %u %d %d %d\n", expire, | |
1048 | dst_entries_get_fast(&ipv4_dst_ops), goal, i); | |
1049 | #endif | |
1050 | ||
1051 | if (dst_entries_get_fast(&ipv4_dst_ops) < ip_rt_max_size) | |
1052 | goto out; | |
1053 | } while (!in_softirq() && time_before_eq(jiffies, now)); | |
1054 | ||
1055 | if (dst_entries_get_fast(&ipv4_dst_ops) < ip_rt_max_size) | |
1056 | goto out; | |
1057 | if (dst_entries_get_slow(&ipv4_dst_ops) < ip_rt_max_size) | |
1058 | goto out; | |
1059 | if (net_ratelimit()) | |
1060 | printk(KERN_WARNING "dst cache overflow\n"); | |
1061 | RT_CACHE_STAT_INC(gc_dst_overflow); | |
1062 | return 1; | |
1063 | ||
1064 | work_done: | |
1065 | expire += ip_rt_gc_min_interval; | |
1066 | if (expire > ip_rt_gc_timeout || | |
1067 | dst_entries_get_fast(&ipv4_dst_ops) < ipv4_dst_ops.gc_thresh || | |
1068 | dst_entries_get_slow(&ipv4_dst_ops) < ipv4_dst_ops.gc_thresh) | |
1069 | expire = ip_rt_gc_timeout; | |
1070 | #if RT_CACHE_DEBUG >= 2 | |
1071 | printk(KERN_DEBUG "expire++ %u %d %d %d\n", expire, | |
1072 | dst_entries_get_fast(&ipv4_dst_ops), goal, rover); | |
1073 | #endif | |
1074 | out: return 0; | |
1075 | } | |
1076 | ||
1077 | /* | |
1078 | * Returns number of entries in a hash chain that have different hash_inputs | |
1079 | */ | |
1080 | static int slow_chain_length(const struct rtable *head) | |
1081 | { | |
1082 | int length = 0; | |
1083 | const struct rtable *rth = head; | |
1084 | ||
1085 | while (rth) { | |
1086 | length += has_noalias(head, rth); | |
1087 | rth = rcu_dereference_protected(rth->dst.rt_next, 1); | |
1088 | } | |
1089 | return length >> FRACT_BITS; | |
1090 | } | |
1091 | ||
1092 | static int rt_intern_hash(unsigned hash, struct rtable *rt, | |
1093 | struct rtable **rp, struct sk_buff *skb, int ifindex) | |
1094 | { | |
1095 | struct rtable *rth, *cand; | |
1096 | struct rtable __rcu **rthp, **candp; | |
1097 | unsigned long now; | |
1098 | u32 min_score; | |
1099 | int chain_length; | |
1100 | int attempts = !in_softirq(); | |
1101 | ||
1102 | restart: | |
1103 | chain_length = 0; | |
1104 | min_score = ~(u32)0; | |
1105 | cand = NULL; | |
1106 | candp = NULL; | |
1107 | now = jiffies; | |
1108 | ||
1109 | if (!rt_caching(dev_net(rt->dst.dev))) { | |
1110 | /* | |
1111 | * If we're not caching, just tell the caller we | |
1112 | * were successful and don't touch the route. The | |
1113 | * caller hold the sole reference to the cache entry, and | |
1114 | * it will be released when the caller is done with it. | |
1115 | * If we drop it here, the callers have no way to resolve routes | |
1116 | * when we're not caching. Instead, just point *rp at rt, so | |
1117 | * the caller gets a single use out of the route | |
1118 | * Note that we do rt_free on this new route entry, so that | |
1119 | * once its refcount hits zero, we are still able to reap it | |
1120 | * (Thanks Alexey) | |
1121 | * Note: To avoid expensive rcu stuff for this uncached dst, | |
1122 | * we set DST_NOCACHE so that dst_release() can free dst without | |
1123 | * waiting a grace period. | |
1124 | */ | |
1125 | ||
1126 | rt->dst.flags |= DST_NOCACHE; | |
1127 | if (rt->rt_type == RTN_UNICAST || rt->fl.iif == 0) { | |
1128 | int err = arp_bind_neighbour(&rt->dst); | |
1129 | if (err) { | |
1130 | if (net_ratelimit()) | |
1131 | printk(KERN_WARNING | |
1132 | "Neighbour table failure & not caching routes.\n"); | |
1133 | ip_rt_put(rt); | |
1134 | return err; | |
1135 | } | |
1136 | } | |
1137 | ||
1138 | goto skip_hashing; | |
1139 | } | |
1140 | ||
1141 | rthp = &rt_hash_table[hash].chain; | |
1142 | ||
1143 | spin_lock_bh(rt_hash_lock_addr(hash)); | |
1144 | while ((rth = rcu_dereference_protected(*rthp, | |
1145 | lockdep_is_held(rt_hash_lock_addr(hash)))) != NULL) { | |
1146 | if (rt_is_expired(rth)) { | |
1147 | *rthp = rth->dst.rt_next; | |
1148 | rt_free(rth); | |
1149 | continue; | |
1150 | } | |
1151 | if (compare_keys(&rth->fl, &rt->fl) && compare_netns(rth, rt)) { | |
1152 | /* Put it first */ | |
1153 | *rthp = rth->dst.rt_next; | |
1154 | /* | |
1155 | * Since lookup is lockfree, the deletion | |
1156 | * must be visible to another weakly ordered CPU before | |
1157 | * the insertion at the start of the hash chain. | |
1158 | */ | |
1159 | rcu_assign_pointer(rth->dst.rt_next, | |
1160 | rt_hash_table[hash].chain); | |
1161 | /* | |
1162 | * Since lookup is lockfree, the update writes | |
1163 | * must be ordered for consistency on SMP. | |
1164 | */ | |
1165 | rcu_assign_pointer(rt_hash_table[hash].chain, rth); | |
1166 | ||
1167 | dst_use(&rth->dst, now); | |
1168 | spin_unlock_bh(rt_hash_lock_addr(hash)); | |
1169 | ||
1170 | rt_drop(rt); | |
1171 | if (rp) | |
1172 | *rp = rth; | |
1173 | else | |
1174 | skb_dst_set(skb, &rth->dst); | |
1175 | return 0; | |
1176 | } | |
1177 | ||
1178 | if (!atomic_read(&rth->dst.__refcnt)) { | |
1179 | u32 score = rt_score(rth); | |
1180 | ||
1181 | if (score <= min_score) { | |
1182 | cand = rth; | |
1183 | candp = rthp; | |
1184 | min_score = score; | |
1185 | } | |
1186 | } | |
1187 | ||
1188 | chain_length++; | |
1189 | ||
1190 | rthp = &rth->dst.rt_next; | |
1191 | } | |
1192 | ||
1193 | if (cand) { | |
1194 | /* ip_rt_gc_elasticity used to be average length of chain | |
1195 | * length, when exceeded gc becomes really aggressive. | |
1196 | * | |
1197 | * The second limit is less certain. At the moment it allows | |
1198 | * only 2 entries per bucket. We will see. | |
1199 | */ | |
1200 | if (chain_length > ip_rt_gc_elasticity) { | |
1201 | *candp = cand->dst.rt_next; | |
1202 | rt_free(cand); | |
1203 | } | |
1204 | } else { | |
1205 | if (chain_length > rt_chain_length_max && | |
1206 | slow_chain_length(rt_hash_table[hash].chain) > rt_chain_length_max) { | |
1207 | struct net *net = dev_net(rt->dst.dev); | |
1208 | int num = ++net->ipv4.current_rt_cache_rebuild_count; | |
1209 | if (!rt_caching(net)) { | |
1210 | printk(KERN_WARNING "%s: %d rebuilds is over limit, route caching disabled\n", | |
1211 | rt->dst.dev->name, num); | |
1212 | } | |
1213 | rt_emergency_hash_rebuild(net); | |
1214 | spin_unlock_bh(rt_hash_lock_addr(hash)); | |
1215 | ||
1216 | hash = rt_hash(rt->fl.fl4_dst, rt->fl.fl4_src, | |
1217 | ifindex, rt_genid(net)); | |
1218 | goto restart; | |
1219 | } | |
1220 | } | |
1221 | ||
1222 | /* Try to bind route to arp only if it is output | |
1223 | route or unicast forwarding path. | |
1224 | */ | |
1225 | if (rt->rt_type == RTN_UNICAST || rt->fl.iif == 0) { | |
1226 | int err = arp_bind_neighbour(&rt->dst); | |
1227 | if (err) { | |
1228 | spin_unlock_bh(rt_hash_lock_addr(hash)); | |
1229 | ||
1230 | if (err != -ENOBUFS) { | |
1231 | rt_drop(rt); | |
1232 | return err; | |
1233 | } | |
1234 | ||
1235 | /* Neighbour tables are full and nothing | |
1236 | can be released. Try to shrink route cache, | |
1237 | it is most likely it holds some neighbour records. | |
1238 | */ | |
1239 | if (attempts-- > 0) { | |
1240 | int saved_elasticity = ip_rt_gc_elasticity; | |
1241 | int saved_int = ip_rt_gc_min_interval; | |
1242 | ip_rt_gc_elasticity = 1; | |
1243 | ip_rt_gc_min_interval = 0; | |
1244 | rt_garbage_collect(&ipv4_dst_ops); | |
1245 | ip_rt_gc_min_interval = saved_int; | |
1246 | ip_rt_gc_elasticity = saved_elasticity; | |
1247 | goto restart; | |
1248 | } | |
1249 | ||
1250 | if (net_ratelimit()) | |
1251 | printk(KERN_WARNING "ipv4: Neighbour table overflow.\n"); | |
1252 | rt_drop(rt); | |
1253 | return -ENOBUFS; | |
1254 | } | |
1255 | } | |
1256 | ||
1257 | rt->dst.rt_next = rt_hash_table[hash].chain; | |
1258 | ||
1259 | #if RT_CACHE_DEBUG >= 2 | |
1260 | if (rt->dst.rt_next) { | |
1261 | struct rtable *trt; | |
1262 | printk(KERN_DEBUG "rt_cache @%02x: %pI4", | |
1263 | hash, &rt->rt_dst); | |
1264 | for (trt = rt->dst.rt_next; trt; trt = trt->dst.rt_next) | |
1265 | printk(" . %pI4", &trt->rt_dst); | |
1266 | printk("\n"); | |
1267 | } | |
1268 | #endif | |
1269 | /* | |
1270 | * Since lookup is lockfree, we must make sure | |
1271 | * previous writes to rt are comitted to memory | |
1272 | * before making rt visible to other CPUS. | |
1273 | */ | |
1274 | rcu_assign_pointer(rt_hash_table[hash].chain, rt); | |
1275 | ||
1276 | spin_unlock_bh(rt_hash_lock_addr(hash)); | |
1277 | ||
1278 | skip_hashing: | |
1279 | if (rp) | |
1280 | *rp = rt; | |
1281 | else | |
1282 | skb_dst_set(skb, &rt->dst); | |
1283 | return 0; | |
1284 | } | |
1285 | ||
1286 | void rt_bind_peer(struct rtable *rt, int create) | |
1287 | { | |
1288 | struct inet_peer *peer; | |
1289 | ||
1290 | peer = inet_getpeer(rt->rt_dst, create); | |
1291 | ||
1292 | if (peer && cmpxchg(&rt->peer, NULL, peer) != NULL) | |
1293 | inet_putpeer(peer); | |
1294 | } | |
1295 | ||
1296 | /* | |
1297 | * Peer allocation may fail only in serious out-of-memory conditions. However | |
1298 | * we still can generate some output. | |
1299 | * Random ID selection looks a bit dangerous because we have no chances to | |
1300 | * select ID being unique in a reasonable period of time. | |
1301 | * But broken packet identifier may be better than no packet at all. | |
1302 | */ | |
1303 | static void ip_select_fb_ident(struct iphdr *iph) | |
1304 | { | |
1305 | static DEFINE_SPINLOCK(ip_fb_id_lock); | |
1306 | static u32 ip_fallback_id; | |
1307 | u32 salt; | |
1308 | ||
1309 | spin_lock_bh(&ip_fb_id_lock); | |
1310 | salt = secure_ip_id((__force __be32)ip_fallback_id ^ iph->daddr); | |
1311 | iph->id = htons(salt & 0xFFFF); | |
1312 | ip_fallback_id = salt; | |
1313 | spin_unlock_bh(&ip_fb_id_lock); | |
1314 | } | |
1315 | ||
1316 | void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more) | |
1317 | { | |
1318 | struct rtable *rt = (struct rtable *) dst; | |
1319 | ||
1320 | if (rt) { | |
1321 | if (rt->peer == NULL) | |
1322 | rt_bind_peer(rt, 1); | |
1323 | ||
1324 | /* If peer is attached to destination, it is never detached, | |
1325 | so that we need not to grab a lock to dereference it. | |
1326 | */ | |
1327 | if (rt->peer) { | |
1328 | iph->id = htons(inet_getid(rt->peer, more)); | |
1329 | return; | |
1330 | } | |
1331 | } else | |
1332 | printk(KERN_DEBUG "rt_bind_peer(0) @%p\n", | |
1333 | __builtin_return_address(0)); | |
1334 | ||
1335 | ip_select_fb_ident(iph); | |
1336 | } | |
1337 | EXPORT_SYMBOL(__ip_select_ident); | |
1338 | ||
1339 | static void rt_del(unsigned hash, struct rtable *rt) | |
1340 | { | |
1341 | struct rtable __rcu **rthp; | |
1342 | struct rtable *aux; | |
1343 | ||
1344 | rthp = &rt_hash_table[hash].chain; | |
1345 | spin_lock_bh(rt_hash_lock_addr(hash)); | |
1346 | ip_rt_put(rt); | |
1347 | while ((aux = rcu_dereference_protected(*rthp, | |
1348 | lockdep_is_held(rt_hash_lock_addr(hash)))) != NULL) { | |
1349 | if (aux == rt || rt_is_expired(aux)) { | |
1350 | *rthp = aux->dst.rt_next; | |
1351 | rt_free(aux); | |
1352 | continue; | |
1353 | } | |
1354 | rthp = &aux->dst.rt_next; | |
1355 | } | |
1356 | spin_unlock_bh(rt_hash_lock_addr(hash)); | |
1357 | } | |
1358 | ||
1359 | /* called in rcu_read_lock() section */ | |
1360 | void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw, | |
1361 | __be32 saddr, struct net_device *dev) | |
1362 | { | |
1363 | int i, k; | |
1364 | struct in_device *in_dev = __in_dev_get_rcu(dev); | |
1365 | struct rtable *rth; | |
1366 | struct rtable __rcu **rthp; | |
1367 | __be32 skeys[2] = { saddr, 0 }; | |
1368 | int ikeys[2] = { dev->ifindex, 0 }; | |
1369 | struct netevent_redirect netevent; | |
1370 | struct net *net; | |
1371 | ||
1372 | if (!in_dev) | |
1373 | return; | |
1374 | ||
1375 | net = dev_net(dev); | |
1376 | if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) || | |
1377 | ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) || | |
1378 | ipv4_is_zeronet(new_gw)) | |
1379 | goto reject_redirect; | |
1380 | ||
1381 | if (!rt_caching(net)) | |
1382 | goto reject_redirect; | |
1383 | ||
1384 | if (!IN_DEV_SHARED_MEDIA(in_dev)) { | |
1385 | if (!inet_addr_onlink(in_dev, new_gw, old_gw)) | |
1386 | goto reject_redirect; | |
1387 | if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev)) | |
1388 | goto reject_redirect; | |
1389 | } else { | |
1390 | if (inet_addr_type(net, new_gw) != RTN_UNICAST) | |
1391 | goto reject_redirect; | |
1392 | } | |
1393 | ||
1394 | for (i = 0; i < 2; i++) { | |
1395 | for (k = 0; k < 2; k++) { | |
1396 | unsigned hash = rt_hash(daddr, skeys[i], ikeys[k], | |
1397 | rt_genid(net)); | |
1398 | ||
1399 | rthp = &rt_hash_table[hash].chain; | |
1400 | ||
1401 | while ((rth = rcu_dereference(*rthp)) != NULL) { | |
1402 | struct rtable *rt; | |
1403 | ||
1404 | if (rth->fl.fl4_dst != daddr || | |
1405 | rth->fl.fl4_src != skeys[i] || | |
1406 | rth->fl.oif != ikeys[k] || | |
1407 | rth->fl.iif != 0 || | |
1408 | rt_is_expired(rth) || | |
1409 | !net_eq(dev_net(rth->dst.dev), net)) { | |
1410 | rthp = &rth->dst.rt_next; | |
1411 | continue; | |
1412 | } | |
1413 | ||
1414 | if (rth->rt_dst != daddr || | |
1415 | rth->rt_src != saddr || | |
1416 | rth->dst.error || | |
1417 | rth->rt_gateway != old_gw || | |
1418 | rth->dst.dev != dev) | |
1419 | break; | |
1420 | ||
1421 | dst_hold(&rth->dst); | |
1422 | ||
1423 | rt = dst_alloc(&ipv4_dst_ops); | |
1424 | if (rt == NULL) { | |
1425 | ip_rt_put(rth); | |
1426 | return; | |
1427 | } | |
1428 | ||
1429 | /* Copy all the information. */ | |
1430 | *rt = *rth; | |
1431 | rt->dst.__use = 1; | |
1432 | atomic_set(&rt->dst.__refcnt, 1); | |
1433 | rt->dst.child = NULL; | |
1434 | if (rt->dst.dev) | |
1435 | dev_hold(rt->dst.dev); | |
1436 | if (rt->idev) | |
1437 | in_dev_hold(rt->idev); | |
1438 | rt->dst.obsolete = -1; | |
1439 | rt->dst.lastuse = jiffies; | |
1440 | rt->dst.path = &rt->dst; | |
1441 | rt->dst.neighbour = NULL; | |
1442 | rt->dst.hh = NULL; | |
1443 | #ifdef CONFIG_XFRM | |
1444 | rt->dst.xfrm = NULL; | |
1445 | #endif | |
1446 | rt->rt_genid = rt_genid(net); | |
1447 | rt->rt_flags |= RTCF_REDIRECTED; | |
1448 | ||
1449 | /* Gateway is different ... */ | |
1450 | rt->rt_gateway = new_gw; | |
1451 | ||
1452 | /* Redirect received -> path was valid */ | |
1453 | dst_confirm(&rth->dst); | |
1454 | ||
1455 | if (rt->peer) | |
1456 | atomic_inc(&rt->peer->refcnt); | |
1457 | ||
1458 | if (arp_bind_neighbour(&rt->dst) || | |
1459 | !(rt->dst.neighbour->nud_state & | |
1460 | NUD_VALID)) { | |
1461 | if (rt->dst.neighbour) | |
1462 | neigh_event_send(rt->dst.neighbour, NULL); | |
1463 | ip_rt_put(rth); | |
1464 | rt_drop(rt); | |
1465 | goto do_next; | |
1466 | } | |
1467 | ||
1468 | netevent.old = &rth->dst; | |
1469 | netevent.new = &rt->dst; | |
1470 | call_netevent_notifiers(NETEVENT_REDIRECT, | |
1471 | &netevent); | |
1472 | ||
1473 | rt_del(hash, rth); | |
1474 | if (!rt_intern_hash(hash, rt, &rt, NULL, rt->fl.oif)) | |
1475 | ip_rt_put(rt); | |
1476 | goto do_next; | |
1477 | } | |
1478 | do_next: | |
1479 | ; | |
1480 | } | |
1481 | } | |
1482 | return; | |
1483 | ||
1484 | reject_redirect: | |
1485 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
1486 | if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) | |
1487 | printk(KERN_INFO "Redirect from %pI4 on %s about %pI4 ignored.\n" | |
1488 | " Advised path = %pI4 -> %pI4\n", | |
1489 | &old_gw, dev->name, &new_gw, | |
1490 | &saddr, &daddr); | |
1491 | #endif | |
1492 | ; | |
1493 | } | |
1494 | ||
1495 | static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst) | |
1496 | { | |
1497 | struct rtable *rt = (struct rtable *)dst; | |
1498 | struct dst_entry *ret = dst; | |
1499 | ||
1500 | if (rt) { | |
1501 | if (dst->obsolete > 0) { | |
1502 | ip_rt_put(rt); | |
1503 | ret = NULL; | |
1504 | } else if ((rt->rt_flags & RTCF_REDIRECTED) || | |
1505 | (rt->dst.expires && | |
1506 | time_after_eq(jiffies, rt->dst.expires))) { | |
1507 | unsigned hash = rt_hash(rt->fl.fl4_dst, rt->fl.fl4_src, | |
1508 | rt->fl.oif, | |
1509 | rt_genid(dev_net(dst->dev))); | |
1510 | #if RT_CACHE_DEBUG >= 1 | |
1511 | printk(KERN_DEBUG "ipv4_negative_advice: redirect to %pI4/%02x dropped\n", | |
1512 | &rt->rt_dst, rt->fl.fl4_tos); | |
1513 | #endif | |
1514 | rt_del(hash, rt); | |
1515 | ret = NULL; | |
1516 | } | |
1517 | } | |
1518 | return ret; | |
1519 | } | |
1520 | ||
1521 | /* | |
1522 | * Algorithm: | |
1523 | * 1. The first ip_rt_redirect_number redirects are sent | |
1524 | * with exponential backoff, then we stop sending them at all, | |
1525 | * assuming that the host ignores our redirects. | |
1526 | * 2. If we did not see packets requiring redirects | |
1527 | * during ip_rt_redirect_silence, we assume that the host | |
1528 | * forgot redirected route and start to send redirects again. | |
1529 | * | |
1530 | * This algorithm is much cheaper and more intelligent than dumb load limiting | |
1531 | * in icmp.c. | |
1532 | * | |
1533 | * NOTE. Do not forget to inhibit load limiting for redirects (redundant) | |
1534 | * and "frag. need" (breaks PMTU discovery) in icmp.c. | |
1535 | */ | |
1536 | ||
1537 | void ip_rt_send_redirect(struct sk_buff *skb) | |
1538 | { | |
1539 | struct rtable *rt = skb_rtable(skb); | |
1540 | struct in_device *in_dev; | |
1541 | int log_martians; | |
1542 | ||
1543 | rcu_read_lock(); | |
1544 | in_dev = __in_dev_get_rcu(rt->dst.dev); | |
1545 | if (!in_dev || !IN_DEV_TX_REDIRECTS(in_dev)) { | |
1546 | rcu_read_unlock(); | |
1547 | return; | |
1548 | } | |
1549 | log_martians = IN_DEV_LOG_MARTIANS(in_dev); | |
1550 | rcu_read_unlock(); | |
1551 | ||
1552 | /* No redirected packets during ip_rt_redirect_silence; | |
1553 | * reset the algorithm. | |
1554 | */ | |
1555 | if (time_after(jiffies, rt->dst.rate_last + ip_rt_redirect_silence)) | |
1556 | rt->dst.rate_tokens = 0; | |
1557 | ||
1558 | /* Too many ignored redirects; do not send anything | |
1559 | * set dst.rate_last to the last seen redirected packet. | |
1560 | */ | |
1561 | if (rt->dst.rate_tokens >= ip_rt_redirect_number) { | |
1562 | rt->dst.rate_last = jiffies; | |
1563 | return; | |
1564 | } | |
1565 | ||
1566 | /* Check for load limit; set rate_last to the latest sent | |
1567 | * redirect. | |
1568 | */ | |
1569 | if (rt->dst.rate_tokens == 0 || | |
1570 | time_after(jiffies, | |
1571 | (rt->dst.rate_last + | |
1572 | (ip_rt_redirect_load << rt->dst.rate_tokens)))) { | |
1573 | icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway); | |
1574 | rt->dst.rate_last = jiffies; | |
1575 | ++rt->dst.rate_tokens; | |
1576 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
1577 | if (log_martians && | |
1578 | rt->dst.rate_tokens == ip_rt_redirect_number && | |
1579 | net_ratelimit()) | |
1580 | printk(KERN_WARNING "host %pI4/if%d ignores redirects for %pI4 to %pI4.\n", | |
1581 | &rt->rt_src, rt->rt_iif, | |
1582 | &rt->rt_dst, &rt->rt_gateway); | |
1583 | #endif | |
1584 | } | |
1585 | } | |
1586 | ||
1587 | static int ip_error(struct sk_buff *skb) | |
1588 | { | |
1589 | struct rtable *rt = skb_rtable(skb); | |
1590 | unsigned long now; | |
1591 | int code; | |
1592 | ||
1593 | switch (rt->dst.error) { | |
1594 | case EINVAL: | |
1595 | default: | |
1596 | goto out; | |
1597 | case EHOSTUNREACH: | |
1598 | code = ICMP_HOST_UNREACH; | |
1599 | break; | |
1600 | case ENETUNREACH: | |
1601 | code = ICMP_NET_UNREACH; | |
1602 | IP_INC_STATS_BH(dev_net(rt->dst.dev), | |
1603 | IPSTATS_MIB_INNOROUTES); | |
1604 | break; | |
1605 | case EACCES: | |
1606 | code = ICMP_PKT_FILTERED; | |
1607 | break; | |
1608 | } | |
1609 | ||
1610 | now = jiffies; | |
1611 | rt->dst.rate_tokens += now - rt->dst.rate_last; | |
1612 | if (rt->dst.rate_tokens > ip_rt_error_burst) | |
1613 | rt->dst.rate_tokens = ip_rt_error_burst; | |
1614 | rt->dst.rate_last = now; | |
1615 | if (rt->dst.rate_tokens >= ip_rt_error_cost) { | |
1616 | rt->dst.rate_tokens -= ip_rt_error_cost; | |
1617 | icmp_send(skb, ICMP_DEST_UNREACH, code, 0); | |
1618 | } | |
1619 | ||
1620 | out: kfree_skb(skb); | |
1621 | return 0; | |
1622 | } | |
1623 | ||
1624 | /* | |
1625 | * The last two values are not from the RFC but | |
1626 | * are needed for AMPRnet AX.25 paths. | |
1627 | */ | |
1628 | ||
1629 | static const unsigned short mtu_plateau[] = | |
1630 | {32000, 17914, 8166, 4352, 2002, 1492, 576, 296, 216, 128 }; | |
1631 | ||
1632 | static inline unsigned short guess_mtu(unsigned short old_mtu) | |
1633 | { | |
1634 | int i; | |
1635 | ||
1636 | for (i = 0; i < ARRAY_SIZE(mtu_plateau); i++) | |
1637 | if (old_mtu > mtu_plateau[i]) | |
1638 | return mtu_plateau[i]; | |
1639 | return 68; | |
1640 | } | |
1641 | ||
1642 | unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph, | |
1643 | unsigned short new_mtu, | |
1644 | struct net_device *dev) | |
1645 | { | |
1646 | int i, k; | |
1647 | unsigned short old_mtu = ntohs(iph->tot_len); | |
1648 | struct rtable *rth; | |
1649 | int ikeys[2] = { dev->ifindex, 0 }; | |
1650 | __be32 skeys[2] = { iph->saddr, 0, }; | |
1651 | __be32 daddr = iph->daddr; | |
1652 | unsigned short est_mtu = 0; | |
1653 | ||
1654 | for (k = 0; k < 2; k++) { | |
1655 | for (i = 0; i < 2; i++) { | |
1656 | unsigned hash = rt_hash(daddr, skeys[i], ikeys[k], | |
1657 | rt_genid(net)); | |
1658 | ||
1659 | rcu_read_lock(); | |
1660 | for (rth = rcu_dereference(rt_hash_table[hash].chain); rth; | |
1661 | rth = rcu_dereference(rth->dst.rt_next)) { | |
1662 | unsigned short mtu = new_mtu; | |
1663 | ||
1664 | if (rth->fl.fl4_dst != daddr || | |
1665 | rth->fl.fl4_src != skeys[i] || | |
1666 | rth->rt_dst != daddr || | |
1667 | rth->rt_src != iph->saddr || | |
1668 | rth->fl.oif != ikeys[k] || | |
1669 | rth->fl.iif != 0 || | |
1670 | dst_metric_locked(&rth->dst, RTAX_MTU) || | |
1671 | !net_eq(dev_net(rth->dst.dev), net) || | |
1672 | rt_is_expired(rth)) | |
1673 | continue; | |
1674 | ||
1675 | if (new_mtu < 68 || new_mtu >= old_mtu) { | |
1676 | ||
1677 | /* BSD 4.2 compatibility hack :-( */ | |
1678 | if (mtu == 0 && | |
1679 | old_mtu >= dst_mtu(&rth->dst) && | |
1680 | old_mtu >= 68 + (iph->ihl << 2)) | |
1681 | old_mtu -= iph->ihl << 2; | |
1682 | ||
1683 | mtu = guess_mtu(old_mtu); | |
1684 | } | |
1685 | if (mtu <= dst_mtu(&rth->dst)) { | |
1686 | if (mtu < dst_mtu(&rth->dst)) { | |
1687 | dst_confirm(&rth->dst); | |
1688 | if (mtu < ip_rt_min_pmtu) { | |
1689 | mtu = ip_rt_min_pmtu; | |
1690 | rth->dst.metrics[RTAX_LOCK-1] |= | |
1691 | (1 << RTAX_MTU); | |
1692 | } | |
1693 | rth->dst.metrics[RTAX_MTU-1] = mtu; | |
1694 | dst_set_expires(&rth->dst, | |
1695 | ip_rt_mtu_expires); | |
1696 | } | |
1697 | est_mtu = mtu; | |
1698 | } | |
1699 | } | |
1700 | rcu_read_unlock(); | |
1701 | } | |
1702 | } | |
1703 | return est_mtu ? : new_mtu; | |
1704 | } | |
1705 | ||
1706 | static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu) | |
1707 | { | |
1708 | if (dst_mtu(dst) > mtu && mtu >= 68 && | |
1709 | !(dst_metric_locked(dst, RTAX_MTU))) { | |
1710 | if (mtu < ip_rt_min_pmtu) { | |
1711 | mtu = ip_rt_min_pmtu; | |
1712 | dst->metrics[RTAX_LOCK-1] |= (1 << RTAX_MTU); | |
1713 | } | |
1714 | dst->metrics[RTAX_MTU-1] = mtu; | |
1715 | dst_set_expires(dst, ip_rt_mtu_expires); | |
1716 | call_netevent_notifiers(NETEVENT_PMTU_UPDATE, dst); | |
1717 | } | |
1718 | } | |
1719 | ||
1720 | static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie) | |
1721 | { | |
1722 | if (rt_is_expired((struct rtable *)dst)) | |
1723 | return NULL; | |
1724 | return dst; | |
1725 | } | |
1726 | ||
1727 | static void ipv4_dst_destroy(struct dst_entry *dst) | |
1728 | { | |
1729 | struct rtable *rt = (struct rtable *) dst; | |
1730 | struct inet_peer *peer = rt->peer; | |
1731 | struct in_device *idev = rt->idev; | |
1732 | ||
1733 | if (peer) { | |
1734 | rt->peer = NULL; | |
1735 | inet_putpeer(peer); | |
1736 | } | |
1737 | ||
1738 | if (idev) { | |
1739 | rt->idev = NULL; | |
1740 | in_dev_put(idev); | |
1741 | } | |
1742 | } | |
1743 | ||
1744 | static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev, | |
1745 | int how) | |
1746 | { | |
1747 | struct rtable *rt = (struct rtable *) dst; | |
1748 | struct in_device *idev = rt->idev; | |
1749 | if (dev != dev_net(dev)->loopback_dev && idev && idev->dev == dev) { | |
1750 | struct in_device *loopback_idev = | |
1751 | in_dev_get(dev_net(dev)->loopback_dev); | |
1752 | if (loopback_idev) { | |
1753 | rt->idev = loopback_idev; | |
1754 | in_dev_put(idev); | |
1755 | } | |
1756 | } | |
1757 | } | |
1758 | ||
1759 | static void ipv4_link_failure(struct sk_buff *skb) | |
1760 | { | |
1761 | struct rtable *rt; | |
1762 | ||
1763 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0); | |
1764 | ||
1765 | rt = skb_rtable(skb); | |
1766 | if (rt) | |
1767 | dst_set_expires(&rt->dst, 0); | |
1768 | } | |
1769 | ||
1770 | static int ip_rt_bug(struct sk_buff *skb) | |
1771 | { | |
1772 | printk(KERN_DEBUG "ip_rt_bug: %pI4 -> %pI4, %s\n", | |
1773 | &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr, | |
1774 | skb->dev ? skb->dev->name : "?"); | |
1775 | kfree_skb(skb); | |
1776 | return 0; | |
1777 | } | |
1778 | ||
1779 | /* | |
1780 | We do not cache source address of outgoing interface, | |
1781 | because it is used only by IP RR, TS and SRR options, | |
1782 | so that it out of fast path. | |
1783 | ||
1784 | BTW remember: "addr" is allowed to be not aligned | |
1785 | in IP options! | |
1786 | */ | |
1787 | ||
1788 | void ip_rt_get_source(u8 *addr, struct rtable *rt) | |
1789 | { | |
1790 | __be32 src; | |
1791 | struct fib_result res; | |
1792 | ||
1793 | if (rt->fl.iif == 0) | |
1794 | src = rt->rt_src; | |
1795 | else { | |
1796 | rcu_read_lock(); | |
1797 | if (fib_lookup(dev_net(rt->dst.dev), &rt->fl, &res) == 0) | |
1798 | src = FIB_RES_PREFSRC(res); | |
1799 | else | |
1800 | src = inet_select_addr(rt->dst.dev, rt->rt_gateway, | |
1801 | RT_SCOPE_UNIVERSE); | |
1802 | rcu_read_unlock(); | |
1803 | } | |
1804 | memcpy(addr, &src, 4); | |
1805 | } | |
1806 | ||
1807 | #ifdef CONFIG_NET_CLS_ROUTE | |
1808 | static void set_class_tag(struct rtable *rt, u32 tag) | |
1809 | { | |
1810 | if (!(rt->dst.tclassid & 0xFFFF)) | |
1811 | rt->dst.tclassid |= tag & 0xFFFF; | |
1812 | if (!(rt->dst.tclassid & 0xFFFF0000)) | |
1813 | rt->dst.tclassid |= tag & 0xFFFF0000; | |
1814 | } | |
1815 | #endif | |
1816 | ||
1817 | static void rt_set_nexthop(struct rtable *rt, struct fib_result *res, u32 itag) | |
1818 | { | |
1819 | struct fib_info *fi = res->fi; | |
1820 | ||
1821 | if (fi) { | |
1822 | if (FIB_RES_GW(*res) && | |
1823 | FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK) | |
1824 | rt->rt_gateway = FIB_RES_GW(*res); | |
1825 | memcpy(rt->dst.metrics, fi->fib_metrics, | |
1826 | sizeof(rt->dst.metrics)); | |
1827 | if (fi->fib_mtu == 0) { | |
1828 | rt->dst.metrics[RTAX_MTU-1] = rt->dst.dev->mtu; | |
1829 | if (dst_metric_locked(&rt->dst, RTAX_MTU) && | |
1830 | rt->rt_gateway != rt->rt_dst && | |
1831 | rt->dst.dev->mtu > 576) | |
1832 | rt->dst.metrics[RTAX_MTU-1] = 576; | |
1833 | } | |
1834 | #ifdef CONFIG_NET_CLS_ROUTE | |
1835 | rt->dst.tclassid = FIB_RES_NH(*res).nh_tclassid; | |
1836 | #endif | |
1837 | } else | |
1838 | rt->dst.metrics[RTAX_MTU-1]= rt->dst.dev->mtu; | |
1839 | ||
1840 | if (dst_metric(&rt->dst, RTAX_HOPLIMIT) == 0) | |
1841 | rt->dst.metrics[RTAX_HOPLIMIT-1] = sysctl_ip_default_ttl; | |
1842 | if (dst_mtu(&rt->dst) > IP_MAX_MTU) | |
1843 | rt->dst.metrics[RTAX_MTU-1] = IP_MAX_MTU; | |
1844 | if (dst_metric(&rt->dst, RTAX_ADVMSS) == 0) | |
1845 | rt->dst.metrics[RTAX_ADVMSS-1] = max_t(unsigned int, rt->dst.dev->mtu - 40, | |
1846 | ip_rt_min_advmss); | |
1847 | if (dst_metric(&rt->dst, RTAX_ADVMSS) > 65535 - 40) | |
1848 | rt->dst.metrics[RTAX_ADVMSS-1] = 65535 - 40; | |
1849 | ||
1850 | #ifdef CONFIG_NET_CLS_ROUTE | |
1851 | #ifdef CONFIG_IP_MULTIPLE_TABLES | |
1852 | set_class_tag(rt, fib_rules_tclass(res)); | |
1853 | #endif | |
1854 | set_class_tag(rt, itag); | |
1855 | #endif | |
1856 | rt->rt_type = res->type; | |
1857 | } | |
1858 | ||
1859 | /* called in rcu_read_lock() section */ | |
1860 | static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr, | |
1861 | u8 tos, struct net_device *dev, int our) | |
1862 | { | |
1863 | unsigned int hash; | |
1864 | struct rtable *rth; | |
1865 | __be32 spec_dst; | |
1866 | struct in_device *in_dev = __in_dev_get_rcu(dev); | |
1867 | u32 itag = 0; | |
1868 | int err; | |
1869 | ||
1870 | /* Primary sanity checks. */ | |
1871 | ||
1872 | if (in_dev == NULL) | |
1873 | return -EINVAL; | |
1874 | ||
1875 | if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) || | |
1876 | ipv4_is_loopback(saddr) || skb->protocol != htons(ETH_P_IP)) | |
1877 | goto e_inval; | |
1878 | ||
1879 | if (ipv4_is_zeronet(saddr)) { | |
1880 | if (!ipv4_is_local_multicast(daddr)) | |
1881 | goto e_inval; | |
1882 | spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK); | |
1883 | } else { | |
1884 | err = fib_validate_source(saddr, 0, tos, 0, dev, &spec_dst, | |
1885 | &itag, 0); | |
1886 | if (err < 0) | |
1887 | goto e_err; | |
1888 | } | |
1889 | rth = dst_alloc(&ipv4_dst_ops); | |
1890 | if (!rth) | |
1891 | goto e_nobufs; | |
1892 | ||
1893 | rth->dst.output = ip_rt_bug; | |
1894 | rth->dst.obsolete = -1; | |
1895 | ||
1896 | atomic_set(&rth->dst.__refcnt, 1); | |
1897 | rth->dst.flags= DST_HOST; | |
1898 | if (IN_DEV_CONF_GET(in_dev, NOPOLICY)) | |
1899 | rth->dst.flags |= DST_NOPOLICY; | |
1900 | rth->fl.fl4_dst = daddr; | |
1901 | rth->rt_dst = daddr; | |
1902 | rth->fl.fl4_tos = tos; | |
1903 | rth->fl.mark = skb->mark; | |
1904 | rth->fl.fl4_src = saddr; | |
1905 | rth->rt_src = saddr; | |
1906 | #ifdef CONFIG_NET_CLS_ROUTE | |
1907 | rth->dst.tclassid = itag; | |
1908 | #endif | |
1909 | rth->rt_iif = | |
1910 | rth->fl.iif = dev->ifindex; | |
1911 | rth->dst.dev = init_net.loopback_dev; | |
1912 | dev_hold(rth->dst.dev); | |
1913 | rth->idev = in_dev_get(rth->dst.dev); | |
1914 | rth->fl.oif = 0; | |
1915 | rth->rt_gateway = daddr; | |
1916 | rth->rt_spec_dst= spec_dst; | |
1917 | rth->rt_genid = rt_genid(dev_net(dev)); | |
1918 | rth->rt_flags = RTCF_MULTICAST; | |
1919 | rth->rt_type = RTN_MULTICAST; | |
1920 | if (our) { | |
1921 | rth->dst.input= ip_local_deliver; | |
1922 | rth->rt_flags |= RTCF_LOCAL; | |
1923 | } | |
1924 | ||
1925 | #ifdef CONFIG_IP_MROUTE | |
1926 | if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev)) | |
1927 | rth->dst.input = ip_mr_input; | |
1928 | #endif | |
1929 | RT_CACHE_STAT_INC(in_slow_mc); | |
1930 | ||
1931 | hash = rt_hash(daddr, saddr, dev->ifindex, rt_genid(dev_net(dev))); | |
1932 | return rt_intern_hash(hash, rth, NULL, skb, dev->ifindex); | |
1933 | ||
1934 | e_nobufs: | |
1935 | return -ENOBUFS; | |
1936 | e_inval: | |
1937 | return -EINVAL; | |
1938 | e_err: | |
1939 | return err; | |
1940 | } | |
1941 | ||
1942 | ||
1943 | static void ip_handle_martian_source(struct net_device *dev, | |
1944 | struct in_device *in_dev, | |
1945 | struct sk_buff *skb, | |
1946 | __be32 daddr, | |
1947 | __be32 saddr) | |
1948 | { | |
1949 | RT_CACHE_STAT_INC(in_martian_src); | |
1950 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
1951 | if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) { | |
1952 | /* | |
1953 | * RFC1812 recommendation, if source is martian, | |
1954 | * the only hint is MAC header. | |
1955 | */ | |
1956 | printk(KERN_WARNING "martian source %pI4 from %pI4, on dev %s\n", | |
1957 | &daddr, &saddr, dev->name); | |
1958 | if (dev->hard_header_len && skb_mac_header_was_set(skb)) { | |
1959 | int i; | |
1960 | const unsigned char *p = skb_mac_header(skb); | |
1961 | printk(KERN_WARNING "ll header: "); | |
1962 | for (i = 0; i < dev->hard_header_len; i++, p++) { | |
1963 | printk("%02x", *p); | |
1964 | if (i < (dev->hard_header_len - 1)) | |
1965 | printk(":"); | |
1966 | } | |
1967 | printk("\n"); | |
1968 | } | |
1969 | } | |
1970 | #endif | |
1971 | } | |
1972 | ||
1973 | /* called in rcu_read_lock() section */ | |
1974 | static int __mkroute_input(struct sk_buff *skb, | |
1975 | struct fib_result *res, | |
1976 | struct in_device *in_dev, | |
1977 | __be32 daddr, __be32 saddr, u32 tos, | |
1978 | struct rtable **result) | |
1979 | { | |
1980 | struct rtable *rth; | |
1981 | int err; | |
1982 | struct in_device *out_dev; | |
1983 | unsigned int flags = 0; | |
1984 | __be32 spec_dst; | |
1985 | u32 itag; | |
1986 | ||
1987 | /* get a working reference to the output device */ | |
1988 | out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res)); | |
1989 | if (out_dev == NULL) { | |
1990 | if (net_ratelimit()) | |
1991 | printk(KERN_CRIT "Bug in ip_route_input" \ | |
1992 | "_slow(). Please, report\n"); | |
1993 | return -EINVAL; | |
1994 | } | |
1995 | ||
1996 | ||
1997 | err = fib_validate_source(saddr, daddr, tos, FIB_RES_OIF(*res), | |
1998 | in_dev->dev, &spec_dst, &itag, skb->mark); | |
1999 | if (err < 0) { | |
2000 | ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr, | |
2001 | saddr); | |
2002 | ||
2003 | goto cleanup; | |
2004 | } | |
2005 | ||
2006 | if (err) | |
2007 | flags |= RTCF_DIRECTSRC; | |
2008 | ||
2009 | if (out_dev == in_dev && err && | |
2010 | (IN_DEV_SHARED_MEDIA(out_dev) || | |
2011 | inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res)))) | |
2012 | flags |= RTCF_DOREDIRECT; | |
2013 | ||
2014 | if (skb->protocol != htons(ETH_P_IP)) { | |
2015 | /* Not IP (i.e. ARP). Do not create route, if it is | |
2016 | * invalid for proxy arp. DNAT routes are always valid. | |
2017 | * | |
2018 | * Proxy arp feature have been extended to allow, ARP | |
2019 | * replies back to the same interface, to support | |
2020 | * Private VLAN switch technologies. See arp.c. | |
2021 | */ | |
2022 | if (out_dev == in_dev && | |
2023 | IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) { | |
2024 | err = -EINVAL; | |
2025 | goto cleanup; | |
2026 | } | |
2027 | } | |
2028 | ||
2029 | ||
2030 | rth = dst_alloc(&ipv4_dst_ops); | |
2031 | if (!rth) { | |
2032 | err = -ENOBUFS; | |
2033 | goto cleanup; | |
2034 | } | |
2035 | ||
2036 | atomic_set(&rth->dst.__refcnt, 1); | |
2037 | rth->dst.flags= DST_HOST; | |
2038 | if (IN_DEV_CONF_GET(in_dev, NOPOLICY)) | |
2039 | rth->dst.flags |= DST_NOPOLICY; | |
2040 | if (IN_DEV_CONF_GET(out_dev, NOXFRM)) | |
2041 | rth->dst.flags |= DST_NOXFRM; | |
2042 | rth->fl.fl4_dst = daddr; | |
2043 | rth->rt_dst = daddr; | |
2044 | rth->fl.fl4_tos = tos; | |
2045 | rth->fl.mark = skb->mark; | |
2046 | rth->fl.fl4_src = saddr; | |
2047 | rth->rt_src = saddr; | |
2048 | rth->rt_gateway = daddr; | |
2049 | rth->rt_iif = | |
2050 | rth->fl.iif = in_dev->dev->ifindex; | |
2051 | rth->dst.dev = (out_dev)->dev; | |
2052 | dev_hold(rth->dst.dev); | |
2053 | rth->idev = in_dev_get(rth->dst.dev); | |
2054 | rth->fl.oif = 0; | |
2055 | rth->rt_spec_dst= spec_dst; | |
2056 | ||
2057 | rth->dst.obsolete = -1; | |
2058 | rth->dst.input = ip_forward; | |
2059 | rth->dst.output = ip_output; | |
2060 | rth->rt_genid = rt_genid(dev_net(rth->dst.dev)); | |
2061 | ||
2062 | rt_set_nexthop(rth, res, itag); | |
2063 | ||
2064 | rth->rt_flags = flags; | |
2065 | ||
2066 | *result = rth; | |
2067 | err = 0; | |
2068 | cleanup: | |
2069 | return err; | |
2070 | } | |
2071 | ||
2072 | static int ip_mkroute_input(struct sk_buff *skb, | |
2073 | struct fib_result *res, | |
2074 | const struct flowi *fl, | |
2075 | struct in_device *in_dev, | |
2076 | __be32 daddr, __be32 saddr, u32 tos) | |
2077 | { | |
2078 | struct rtable* rth = NULL; | |
2079 | int err; | |
2080 | unsigned hash; | |
2081 | ||
2082 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
2083 | if (res->fi && res->fi->fib_nhs > 1 && fl->oif == 0) | |
2084 | fib_select_multipath(fl, res); | |
2085 | #endif | |
2086 | ||
2087 | /* create a routing cache entry */ | |
2088 | err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, &rth); | |
2089 | if (err) | |
2090 | return err; | |
2091 | ||
2092 | /* put it into the cache */ | |
2093 | hash = rt_hash(daddr, saddr, fl->iif, | |
2094 | rt_genid(dev_net(rth->dst.dev))); | |
2095 | return rt_intern_hash(hash, rth, NULL, skb, fl->iif); | |
2096 | } | |
2097 | ||
2098 | /* | |
2099 | * NOTE. We drop all the packets that has local source | |
2100 | * addresses, because every properly looped back packet | |
2101 | * must have correct destination already attached by output routine. | |
2102 | * | |
2103 | * Such approach solves two big problems: | |
2104 | * 1. Not simplex devices are handled properly. | |
2105 | * 2. IP spoofing attempts are filtered with 100% of guarantee. | |
2106 | * called with rcu_read_lock() | |
2107 | */ | |
2108 | ||
2109 | static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr, | |
2110 | u8 tos, struct net_device *dev) | |
2111 | { | |
2112 | struct fib_result res; | |
2113 | struct in_device *in_dev = __in_dev_get_rcu(dev); | |
2114 | struct flowi fl = { .nl_u = { .ip4_u = | |
2115 | { .daddr = daddr, | |
2116 | .saddr = saddr, | |
2117 | .tos = tos, | |
2118 | .scope = RT_SCOPE_UNIVERSE, | |
2119 | } }, | |
2120 | .mark = skb->mark, | |
2121 | .iif = dev->ifindex }; | |
2122 | unsigned flags = 0; | |
2123 | u32 itag = 0; | |
2124 | struct rtable * rth; | |
2125 | unsigned hash; | |
2126 | __be32 spec_dst; | |
2127 | int err = -EINVAL; | |
2128 | struct net * net = dev_net(dev); | |
2129 | ||
2130 | /* IP on this device is disabled. */ | |
2131 | ||
2132 | if (!in_dev) | |
2133 | goto out; | |
2134 | ||
2135 | /* Check for the most weird martians, which can be not detected | |
2136 | by fib_lookup. | |
2137 | */ | |
2138 | ||
2139 | if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) || | |
2140 | ipv4_is_loopback(saddr)) | |
2141 | goto martian_source; | |
2142 | ||
2143 | if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0)) | |
2144 | goto brd_input; | |
2145 | ||
2146 | /* Accept zero addresses only to limited broadcast; | |
2147 | * I even do not know to fix it or not. Waiting for complains :-) | |
2148 | */ | |
2149 | if (ipv4_is_zeronet(saddr)) | |
2150 | goto martian_source; | |
2151 | ||
2152 | if (ipv4_is_zeronet(daddr) || ipv4_is_loopback(daddr)) | |
2153 | goto martian_destination; | |
2154 | ||
2155 | /* | |
2156 | * Now we are ready to route packet. | |
2157 | */ | |
2158 | err = fib_lookup(net, &fl, &res); | |
2159 | if (err != 0) { | |
2160 | if (!IN_DEV_FORWARD(in_dev)) | |
2161 | goto e_hostunreach; | |
2162 | goto no_route; | |
2163 | } | |
2164 | ||
2165 | RT_CACHE_STAT_INC(in_slow_tot); | |
2166 | ||
2167 | if (res.type == RTN_BROADCAST) | |
2168 | goto brd_input; | |
2169 | ||
2170 | if (res.type == RTN_LOCAL) { | |
2171 | err = fib_validate_source(saddr, daddr, tos, | |
2172 | net->loopback_dev->ifindex, | |
2173 | dev, &spec_dst, &itag, skb->mark); | |
2174 | if (err < 0) | |
2175 | goto martian_source_keep_err; | |
2176 | if (err) | |
2177 | flags |= RTCF_DIRECTSRC; | |
2178 | spec_dst = daddr; | |
2179 | goto local_input; | |
2180 | } | |
2181 | ||
2182 | if (!IN_DEV_FORWARD(in_dev)) | |
2183 | goto e_hostunreach; | |
2184 | if (res.type != RTN_UNICAST) | |
2185 | goto martian_destination; | |
2186 | ||
2187 | err = ip_mkroute_input(skb, &res, &fl, in_dev, daddr, saddr, tos); | |
2188 | out: return err; | |
2189 | ||
2190 | brd_input: | |
2191 | if (skb->protocol != htons(ETH_P_IP)) | |
2192 | goto e_inval; | |
2193 | ||
2194 | if (ipv4_is_zeronet(saddr)) | |
2195 | spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK); | |
2196 | else { | |
2197 | err = fib_validate_source(saddr, 0, tos, 0, dev, &spec_dst, | |
2198 | &itag, skb->mark); | |
2199 | if (err < 0) | |
2200 | goto martian_source_keep_err; | |
2201 | if (err) | |
2202 | flags |= RTCF_DIRECTSRC; | |
2203 | } | |
2204 | flags |= RTCF_BROADCAST; | |
2205 | res.type = RTN_BROADCAST; | |
2206 | RT_CACHE_STAT_INC(in_brd); | |
2207 | ||
2208 | local_input: | |
2209 | rth = dst_alloc(&ipv4_dst_ops); | |
2210 | if (!rth) | |
2211 | goto e_nobufs; | |
2212 | ||
2213 | rth->dst.output= ip_rt_bug; | |
2214 | rth->dst.obsolete = -1; | |
2215 | rth->rt_genid = rt_genid(net); | |
2216 | ||
2217 | atomic_set(&rth->dst.__refcnt, 1); | |
2218 | rth->dst.flags= DST_HOST; | |
2219 | if (IN_DEV_CONF_GET(in_dev, NOPOLICY)) | |
2220 | rth->dst.flags |= DST_NOPOLICY; | |
2221 | rth->fl.fl4_dst = daddr; | |
2222 | rth->rt_dst = daddr; | |
2223 | rth->fl.fl4_tos = tos; | |
2224 | rth->fl.mark = skb->mark; | |
2225 | rth->fl.fl4_src = saddr; | |
2226 | rth->rt_src = saddr; | |
2227 | #ifdef CONFIG_NET_CLS_ROUTE | |
2228 | rth->dst.tclassid = itag; | |
2229 | #endif | |
2230 | rth->rt_iif = | |
2231 | rth->fl.iif = dev->ifindex; | |
2232 | rth->dst.dev = net->loopback_dev; | |
2233 | dev_hold(rth->dst.dev); | |
2234 | rth->idev = in_dev_get(rth->dst.dev); | |
2235 | rth->rt_gateway = daddr; | |
2236 | rth->rt_spec_dst= spec_dst; | |
2237 | rth->dst.input= ip_local_deliver; | |
2238 | rth->rt_flags = flags|RTCF_LOCAL; | |
2239 | if (res.type == RTN_UNREACHABLE) { | |
2240 | rth->dst.input= ip_error; | |
2241 | rth->dst.error= -err; | |
2242 | rth->rt_flags &= ~RTCF_LOCAL; | |
2243 | } | |
2244 | rth->rt_type = res.type; | |
2245 | hash = rt_hash(daddr, saddr, fl.iif, rt_genid(net)); | |
2246 | err = rt_intern_hash(hash, rth, NULL, skb, fl.iif); | |
2247 | goto out; | |
2248 | ||
2249 | no_route: | |
2250 | RT_CACHE_STAT_INC(in_no_route); | |
2251 | spec_dst = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE); | |
2252 | res.type = RTN_UNREACHABLE; | |
2253 | if (err == -ESRCH) | |
2254 | err = -ENETUNREACH; | |
2255 | goto local_input; | |
2256 | ||
2257 | /* | |
2258 | * Do not cache martian addresses: they should be logged (RFC1812) | |
2259 | */ | |
2260 | martian_destination: | |
2261 | RT_CACHE_STAT_INC(in_martian_dst); | |
2262 | #ifdef CONFIG_IP_ROUTE_VERBOSE | |
2263 | if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) | |
2264 | printk(KERN_WARNING "martian destination %pI4 from %pI4, dev %s\n", | |
2265 | &daddr, &saddr, dev->name); | |
2266 | #endif | |
2267 | ||
2268 | e_hostunreach: | |
2269 | err = -EHOSTUNREACH; | |
2270 | goto out; | |
2271 | ||
2272 | e_inval: | |
2273 | err = -EINVAL; | |
2274 | goto out; | |
2275 | ||
2276 | e_nobufs: | |
2277 | err = -ENOBUFS; | |
2278 | goto out; | |
2279 | ||
2280 | martian_source: | |
2281 | err = -EINVAL; | |
2282 | martian_source_keep_err: | |
2283 | ip_handle_martian_source(dev, in_dev, skb, daddr, saddr); | |
2284 | goto out; | |
2285 | } | |
2286 | ||
2287 | int ip_route_input_common(struct sk_buff *skb, __be32 daddr, __be32 saddr, | |
2288 | u8 tos, struct net_device *dev, bool noref) | |
2289 | { | |
2290 | struct rtable * rth; | |
2291 | unsigned hash; | |
2292 | int iif = dev->ifindex; | |
2293 | struct net *net; | |
2294 | int res; | |
2295 | ||
2296 | net = dev_net(dev); | |
2297 | ||
2298 | rcu_read_lock(); | |
2299 | ||
2300 | if (!rt_caching(net)) | |
2301 | goto skip_cache; | |
2302 | ||
2303 | tos &= IPTOS_RT_MASK; | |
2304 | hash = rt_hash(daddr, saddr, iif, rt_genid(net)); | |
2305 | ||
2306 | for (rth = rcu_dereference(rt_hash_table[hash].chain); rth; | |
2307 | rth = rcu_dereference(rth->dst.rt_next)) { | |
2308 | if ((((__force u32)rth->fl.fl4_dst ^ (__force u32)daddr) | | |
2309 | ((__force u32)rth->fl.fl4_src ^ (__force u32)saddr) | | |
2310 | (rth->fl.iif ^ iif) | | |
2311 | rth->fl.oif | | |
2312 | (rth->fl.fl4_tos ^ tos)) == 0 && | |
2313 | rth->fl.mark == skb->mark && | |
2314 | net_eq(dev_net(rth->dst.dev), net) && | |
2315 | !rt_is_expired(rth)) { | |
2316 | if (noref) { | |
2317 | dst_use_noref(&rth->dst, jiffies); | |
2318 | skb_dst_set_noref(skb, &rth->dst); | |
2319 | } else { | |
2320 | dst_use(&rth->dst, jiffies); | |
2321 | skb_dst_set(skb, &rth->dst); | |
2322 | } | |
2323 | RT_CACHE_STAT_INC(in_hit); | |
2324 | rcu_read_unlock(); | |
2325 | return 0; | |
2326 | } | |
2327 | RT_CACHE_STAT_INC(in_hlist_search); | |
2328 | } | |
2329 | ||
2330 | skip_cache: | |
2331 | /* Multicast recognition logic is moved from route cache to here. | |
2332 | The problem was that too many Ethernet cards have broken/missing | |
2333 | hardware multicast filters :-( As result the host on multicasting | |
2334 | network acquires a lot of useless route cache entries, sort of | |
2335 | SDR messages from all the world. Now we try to get rid of them. | |
2336 | Really, provided software IP multicast filter is organized | |
2337 | reasonably (at least, hashed), it does not result in a slowdown | |
2338 | comparing with route cache reject entries. | |
2339 | Note, that multicast routers are not affected, because | |
2340 | route cache entry is created eventually. | |
2341 | */ | |
2342 | if (ipv4_is_multicast(daddr)) { | |
2343 | struct in_device *in_dev = __in_dev_get_rcu(dev); | |
2344 | ||
2345 | if (in_dev) { | |
2346 | int our = ip_check_mc(in_dev, daddr, saddr, | |
2347 | ip_hdr(skb)->protocol); | |
2348 | if (our | |
2349 | #ifdef CONFIG_IP_MROUTE | |
2350 | || | |
2351 | (!ipv4_is_local_multicast(daddr) && | |
2352 | IN_DEV_MFORWARD(in_dev)) | |
2353 | #endif | |
2354 | ) { | |
2355 | int res = ip_route_input_mc(skb, daddr, saddr, | |
2356 | tos, dev, our); | |
2357 | rcu_read_unlock(); | |
2358 | return res; | |
2359 | } | |
2360 | } | |
2361 | rcu_read_unlock(); | |
2362 | return -EINVAL; | |
2363 | } | |
2364 | res = ip_route_input_slow(skb, daddr, saddr, tos, dev); | |
2365 | rcu_read_unlock(); | |
2366 | return res; | |
2367 | } | |
2368 | EXPORT_SYMBOL(ip_route_input_common); | |
2369 | ||
2370 | /* called with rcu_read_lock() */ | |
2371 | static int __mkroute_output(struct rtable **result, | |
2372 | struct fib_result *res, | |
2373 | const struct flowi *fl, | |
2374 | const struct flowi *oldflp, | |
2375 | struct net_device *dev_out, | |
2376 | unsigned flags) | |
2377 | { | |
2378 | struct rtable *rth; | |
2379 | struct in_device *in_dev; | |
2380 | u32 tos = RT_FL_TOS(oldflp); | |
2381 | ||
2382 | if (ipv4_is_loopback(fl->fl4_src) && !(dev_out->flags & IFF_LOOPBACK)) | |
2383 | return -EINVAL; | |
2384 | ||
2385 | if (ipv4_is_lbcast(fl->fl4_dst)) | |
2386 | res->type = RTN_BROADCAST; | |
2387 | else if (ipv4_is_multicast(fl->fl4_dst)) | |
2388 | res->type = RTN_MULTICAST; | |
2389 | else if (ipv4_is_zeronet(fl->fl4_dst)) | |
2390 | return -EINVAL; | |
2391 | ||
2392 | if (dev_out->flags & IFF_LOOPBACK) | |
2393 | flags |= RTCF_LOCAL; | |
2394 | ||
2395 | in_dev = __in_dev_get_rcu(dev_out); | |
2396 | if (!in_dev) | |
2397 | return -EINVAL; | |
2398 | ||
2399 | if (res->type == RTN_BROADCAST) { | |
2400 | flags |= RTCF_BROADCAST | RTCF_LOCAL; | |
2401 | res->fi = NULL; | |
2402 | } else if (res->type == RTN_MULTICAST) { | |
2403 | flags |= RTCF_MULTICAST | RTCF_LOCAL; | |
2404 | if (!ip_check_mc(in_dev, oldflp->fl4_dst, oldflp->fl4_src, | |
2405 | oldflp->proto)) | |
2406 | flags &= ~RTCF_LOCAL; | |
2407 | /* If multicast route do not exist use | |
2408 | * default one, but do not gateway in this case. | |
2409 | * Yes, it is hack. | |
2410 | */ | |
2411 | if (res->fi && res->prefixlen < 4) | |
2412 | res->fi = NULL; | |
2413 | } | |
2414 | ||
2415 | ||
2416 | rth = dst_alloc(&ipv4_dst_ops); | |
2417 | if (!rth) | |
2418 | return -ENOBUFS; | |
2419 | ||
2420 | in_dev_hold(in_dev); | |
2421 | rth->idev = in_dev; | |
2422 | ||
2423 | atomic_set(&rth->dst.__refcnt, 1); | |
2424 | rth->dst.flags= DST_HOST; | |
2425 | if (IN_DEV_CONF_GET(in_dev, NOXFRM)) | |
2426 | rth->dst.flags |= DST_NOXFRM; | |
2427 | if (IN_DEV_CONF_GET(in_dev, NOPOLICY)) | |
2428 | rth->dst.flags |= DST_NOPOLICY; | |
2429 | ||
2430 | rth->fl.fl4_dst = oldflp->fl4_dst; | |
2431 | rth->fl.fl4_tos = tos; | |
2432 | rth->fl.fl4_src = oldflp->fl4_src; | |
2433 | rth->fl.oif = oldflp->oif; | |
2434 | rth->fl.mark = oldflp->mark; | |
2435 | rth->rt_dst = fl->fl4_dst; | |
2436 | rth->rt_src = fl->fl4_src; | |
2437 | rth->rt_iif = oldflp->oif ? : dev_out->ifindex; | |
2438 | /* get references to the devices that are to be hold by the routing | |
2439 | cache entry */ | |
2440 | rth->dst.dev = dev_out; | |
2441 | dev_hold(dev_out); | |
2442 | rth->rt_gateway = fl->fl4_dst; | |
2443 | rth->rt_spec_dst= fl->fl4_src; | |
2444 | ||
2445 | rth->dst.output=ip_output; | |
2446 | rth->dst.obsolete = -1; | |
2447 | rth->rt_genid = rt_genid(dev_net(dev_out)); | |
2448 | ||
2449 | RT_CACHE_STAT_INC(out_slow_tot); | |
2450 | ||
2451 | if (flags & RTCF_LOCAL) { | |
2452 | rth->dst.input = ip_local_deliver; | |
2453 | rth->rt_spec_dst = fl->fl4_dst; | |
2454 | } | |
2455 | if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) { | |
2456 | rth->rt_spec_dst = fl->fl4_src; | |
2457 | if (flags & RTCF_LOCAL && | |
2458 | !(dev_out->flags & IFF_LOOPBACK)) { | |
2459 | rth->dst.output = ip_mc_output; | |
2460 | RT_CACHE_STAT_INC(out_slow_mc); | |
2461 | } | |
2462 | #ifdef CONFIG_IP_MROUTE | |
2463 | if (res->type == RTN_MULTICAST) { | |
2464 | if (IN_DEV_MFORWARD(in_dev) && | |
2465 | !ipv4_is_local_multicast(oldflp->fl4_dst)) { | |
2466 | rth->dst.input = ip_mr_input; | |
2467 | rth->dst.output = ip_mc_output; | |
2468 | } | |
2469 | } | |
2470 | #endif | |
2471 | } | |
2472 | ||
2473 | rt_set_nexthop(rth, res, 0); | |
2474 | ||
2475 | rth->rt_flags = flags; | |
2476 | *result = rth; | |
2477 | return 0; | |
2478 | } | |
2479 | ||
2480 | /* called with rcu_read_lock() */ | |
2481 | static int ip_mkroute_output(struct rtable **rp, | |
2482 | struct fib_result *res, | |
2483 | const struct flowi *fl, | |
2484 | const struct flowi *oldflp, | |
2485 | struct net_device *dev_out, | |
2486 | unsigned flags) | |
2487 | { | |
2488 | struct rtable *rth = NULL; | |
2489 | int err = __mkroute_output(&rth, res, fl, oldflp, dev_out, flags); | |
2490 | unsigned hash; | |
2491 | if (err == 0) { | |
2492 | hash = rt_hash(oldflp->fl4_dst, oldflp->fl4_src, oldflp->oif, | |
2493 | rt_genid(dev_net(dev_out))); | |
2494 | err = rt_intern_hash(hash, rth, rp, NULL, oldflp->oif); | |
2495 | } | |
2496 | ||
2497 | return err; | |
2498 | } | |
2499 | ||
2500 | /* | |
2501 | * Major route resolver routine. | |
2502 | * called with rcu_read_lock(); | |
2503 | */ | |
2504 | ||
2505 | static int ip_route_output_slow(struct net *net, struct rtable **rp, | |
2506 | const struct flowi *oldflp) | |
2507 | { | |
2508 | u32 tos = RT_FL_TOS(oldflp); | |
2509 | struct flowi fl = { .nl_u = { .ip4_u = | |
2510 | { .daddr = oldflp->fl4_dst, | |
2511 | .saddr = oldflp->fl4_src, | |
2512 | .tos = tos & IPTOS_RT_MASK, | |
2513 | .scope = ((tos & RTO_ONLINK) ? | |
2514 | RT_SCOPE_LINK : | |
2515 | RT_SCOPE_UNIVERSE), | |
2516 | } }, | |
2517 | .mark = oldflp->mark, | |
2518 | .iif = net->loopback_dev->ifindex, | |
2519 | .oif = oldflp->oif }; | |
2520 | struct fib_result res; | |
2521 | unsigned int flags = 0; | |
2522 | struct net_device *dev_out = NULL; | |
2523 | int err; | |
2524 | ||
2525 | ||
2526 | res.fi = NULL; | |
2527 | #ifdef CONFIG_IP_MULTIPLE_TABLES | |
2528 | res.r = NULL; | |
2529 | #endif | |
2530 | ||
2531 | if (oldflp->fl4_src) { | |
2532 | err = -EINVAL; | |
2533 | if (ipv4_is_multicast(oldflp->fl4_src) || | |
2534 | ipv4_is_lbcast(oldflp->fl4_src) || | |
2535 | ipv4_is_zeronet(oldflp->fl4_src)) | |
2536 | goto out; | |
2537 | ||
2538 | /* I removed check for oif == dev_out->oif here. | |
2539 | It was wrong for two reasons: | |
2540 | 1. ip_dev_find(net, saddr) can return wrong iface, if saddr | |
2541 | is assigned to multiple interfaces. | |
2542 | 2. Moreover, we are allowed to send packets with saddr | |
2543 | of another iface. --ANK | |
2544 | */ | |
2545 | ||
2546 | if (oldflp->oif == 0 && | |
2547 | (ipv4_is_multicast(oldflp->fl4_dst) || | |
2548 | ipv4_is_lbcast(oldflp->fl4_dst))) { | |
2549 | /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ | |
2550 | dev_out = __ip_dev_find(net, oldflp->fl4_src, false); | |
2551 | if (dev_out == NULL) | |
2552 | goto out; | |
2553 | ||
2554 | /* Special hack: user can direct multicasts | |
2555 | and limited broadcast via necessary interface | |
2556 | without fiddling with IP_MULTICAST_IF or IP_PKTINFO. | |
2557 | This hack is not just for fun, it allows | |
2558 | vic,vat and friends to work. | |
2559 | They bind socket to loopback, set ttl to zero | |
2560 | and expect that it will work. | |
2561 | From the viewpoint of routing cache they are broken, | |
2562 | because we are not allowed to build multicast path | |
2563 | with loopback source addr (look, routing cache | |
2564 | cannot know, that ttl is zero, so that packet | |
2565 | will not leave this host and route is valid). | |
2566 | Luckily, this hack is good workaround. | |
2567 | */ | |
2568 | ||
2569 | fl.oif = dev_out->ifindex; | |
2570 | goto make_route; | |
2571 | } | |
2572 | ||
2573 | if (!(oldflp->flags & FLOWI_FLAG_ANYSRC)) { | |
2574 | /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ | |
2575 | if (!__ip_dev_find(net, oldflp->fl4_src, false)) | |
2576 | goto out; | |
2577 | } | |
2578 | } | |
2579 | ||
2580 | ||
2581 | if (oldflp->oif) { | |
2582 | dev_out = dev_get_by_index_rcu(net, oldflp->oif); | |
2583 | err = -ENODEV; | |
2584 | if (dev_out == NULL) | |
2585 | goto out; | |
2586 | ||
2587 | /* RACE: Check return value of inet_select_addr instead. */ | |
2588 | if (rcu_dereference(dev_out->ip_ptr) == NULL) | |
2589 | goto out; /* Wrong error code */ | |
2590 | ||
2591 | if (ipv4_is_local_multicast(oldflp->fl4_dst) || | |
2592 | ipv4_is_lbcast(oldflp->fl4_dst)) { | |
2593 | if (!fl.fl4_src) | |
2594 | fl.fl4_src = inet_select_addr(dev_out, 0, | |
2595 | RT_SCOPE_LINK); | |
2596 | goto make_route; | |
2597 | } | |
2598 | if (!fl.fl4_src) { | |
2599 | if (ipv4_is_multicast(oldflp->fl4_dst)) | |
2600 | fl.fl4_src = inet_select_addr(dev_out, 0, | |
2601 | fl.fl4_scope); | |
2602 | else if (!oldflp->fl4_dst) | |
2603 | fl.fl4_src = inet_select_addr(dev_out, 0, | |
2604 | RT_SCOPE_HOST); | |
2605 | } | |
2606 | } | |
2607 | ||
2608 | if (!fl.fl4_dst) { | |
2609 | fl.fl4_dst = fl.fl4_src; | |
2610 | if (!fl.fl4_dst) | |
2611 | fl.fl4_dst = fl.fl4_src = htonl(INADDR_LOOPBACK); | |
2612 | dev_out = net->loopback_dev; | |
2613 | fl.oif = net->loopback_dev->ifindex; | |
2614 | res.type = RTN_LOCAL; | |
2615 | flags |= RTCF_LOCAL; | |
2616 | goto make_route; | |
2617 | } | |
2618 | ||
2619 | if (fib_lookup(net, &fl, &res)) { | |
2620 | res.fi = NULL; | |
2621 | if (oldflp->oif) { | |
2622 | /* Apparently, routing tables are wrong. Assume, | |
2623 | that the destination is on link. | |
2624 | ||
2625 | WHY? DW. | |
2626 | Because we are allowed to send to iface | |
2627 | even if it has NO routes and NO assigned | |
2628 | addresses. When oif is specified, routing | |
2629 | tables are looked up with only one purpose: | |
2630 | to catch if destination is gatewayed, rather than | |
2631 | direct. Moreover, if MSG_DONTROUTE is set, | |
2632 | we send packet, ignoring both routing tables | |
2633 | and ifaddr state. --ANK | |
2634 | ||
2635 | ||
2636 | We could make it even if oif is unknown, | |
2637 | likely IPv6, but we do not. | |
2638 | */ | |
2639 | ||
2640 | if (fl.fl4_src == 0) | |
2641 | fl.fl4_src = inet_select_addr(dev_out, 0, | |
2642 | RT_SCOPE_LINK); | |
2643 | res.type = RTN_UNICAST; | |
2644 | goto make_route; | |
2645 | } | |
2646 | err = -ENETUNREACH; | |
2647 | goto out; | |
2648 | } | |
2649 | ||
2650 | if (res.type == RTN_LOCAL) { | |
2651 | if (!fl.fl4_src) | |
2652 | fl.fl4_src = fl.fl4_dst; | |
2653 | dev_out = net->loopback_dev; | |
2654 | fl.oif = dev_out->ifindex; | |
2655 | res.fi = NULL; | |
2656 | flags |= RTCF_LOCAL; | |
2657 | goto make_route; | |
2658 | } | |
2659 | ||
2660 | #ifdef CONFIG_IP_ROUTE_MULTIPATH | |
2661 | if (res.fi->fib_nhs > 1 && fl.oif == 0) | |
2662 | fib_select_multipath(&fl, &res); | |
2663 | else | |
2664 | #endif | |
2665 | if (!res.prefixlen && res.type == RTN_UNICAST && !fl.oif) | |
2666 | fib_select_default(net, &fl, &res); | |
2667 | ||
2668 | if (!fl.fl4_src) | |
2669 | fl.fl4_src = FIB_RES_PREFSRC(res); | |
2670 | ||
2671 | dev_out = FIB_RES_DEV(res); | |
2672 | fl.oif = dev_out->ifindex; | |
2673 | ||
2674 | ||
2675 | make_route: | |
2676 | err = ip_mkroute_output(rp, &res, &fl, oldflp, dev_out, flags); | |
2677 | ||
2678 | out: return err; | |
2679 | } | |
2680 | ||
2681 | int __ip_route_output_key(struct net *net, struct rtable **rp, | |
2682 | const struct flowi *flp) | |
2683 | { | |
2684 | unsigned int hash; | |
2685 | int res; | |
2686 | struct rtable *rth; | |
2687 | ||
2688 | if (!rt_caching(net)) | |
2689 | goto slow_output; | |
2690 | ||
2691 | hash = rt_hash(flp->fl4_dst, flp->fl4_src, flp->oif, rt_genid(net)); | |
2692 | ||
2693 | rcu_read_lock_bh(); | |
2694 | for (rth = rcu_dereference_bh(rt_hash_table[hash].chain); rth; | |
2695 | rth = rcu_dereference_bh(rth->dst.rt_next)) { | |
2696 | if (rth->fl.fl4_dst == flp->fl4_dst && | |
2697 | rth->fl.fl4_src == flp->fl4_src && | |
2698 | rth->fl.iif == 0 && | |
2699 | rth->fl.oif == flp->oif && | |
2700 | rth->fl.mark == flp->mark && | |
2701 | !((rth->fl.fl4_tos ^ flp->fl4_tos) & | |
2702 | (IPTOS_RT_MASK | RTO_ONLINK)) && | |
2703 | net_eq(dev_net(rth->dst.dev), net) && | |
2704 | !rt_is_expired(rth)) { | |
2705 | dst_use(&rth->dst, jiffies); | |
2706 | RT_CACHE_STAT_INC(out_hit); | |
2707 | rcu_read_unlock_bh(); | |
2708 | *rp = rth; | |
2709 | return 0; | |
2710 | } | |
2711 | RT_CACHE_STAT_INC(out_hlist_search); | |
2712 | } | |
2713 | rcu_read_unlock_bh(); | |
2714 | ||
2715 | slow_output: | |
2716 | rcu_read_lock(); | |
2717 | res = ip_route_output_slow(net, rp, flp); | |
2718 | rcu_read_unlock(); | |
2719 | return res; | |
2720 | } | |
2721 | EXPORT_SYMBOL_GPL(__ip_route_output_key); | |
2722 | ||
2723 | static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie) | |
2724 | { | |
2725 | return NULL; | |
2726 | } | |
2727 | ||
2728 | static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu) | |
2729 | { | |
2730 | } | |
2731 | ||
2732 | static struct dst_ops ipv4_dst_blackhole_ops = { | |
2733 | .family = AF_INET, | |
2734 | .protocol = cpu_to_be16(ETH_P_IP), | |
2735 | .destroy = ipv4_dst_destroy, | |
2736 | .check = ipv4_blackhole_dst_check, | |
2737 | .update_pmtu = ipv4_rt_blackhole_update_pmtu, | |
2738 | }; | |
2739 | ||
2740 | ||
2741 | static int ipv4_dst_blackhole(struct net *net, struct rtable **rp, struct flowi *flp) | |
2742 | { | |
2743 | struct rtable *ort = *rp; | |
2744 | struct rtable *rt = (struct rtable *) | |
2745 | dst_alloc(&ipv4_dst_blackhole_ops); | |
2746 | ||
2747 | if (rt) { | |
2748 | struct dst_entry *new = &rt->dst; | |
2749 | ||
2750 | atomic_set(&new->__refcnt, 1); | |
2751 | new->__use = 1; | |
2752 | new->input = dst_discard; | |
2753 | new->output = dst_discard; | |
2754 | memcpy(new->metrics, ort->dst.metrics, RTAX_MAX*sizeof(u32)); | |
2755 | ||
2756 | new->dev = ort->dst.dev; | |
2757 | if (new->dev) | |
2758 | dev_hold(new->dev); | |
2759 | ||
2760 | rt->fl = ort->fl; | |
2761 | ||
2762 | rt->idev = ort->idev; | |
2763 | if (rt->idev) | |
2764 | in_dev_hold(rt->idev); | |
2765 | rt->rt_genid = rt_genid(net); | |
2766 | rt->rt_flags = ort->rt_flags; | |
2767 | rt->rt_type = ort->rt_type; | |
2768 | rt->rt_dst = ort->rt_dst; | |
2769 | rt->rt_src = ort->rt_src; | |
2770 | rt->rt_iif = ort->rt_iif; | |
2771 | rt->rt_gateway = ort->rt_gateway; | |
2772 | rt->rt_spec_dst = ort->rt_spec_dst; | |
2773 | rt->peer = ort->peer; | |
2774 | if (rt->peer) | |
2775 | atomic_inc(&rt->peer->refcnt); | |
2776 | ||
2777 | dst_free(new); | |
2778 | } | |
2779 | ||
2780 | dst_release(&(*rp)->dst); | |
2781 | *rp = rt; | |
2782 | return rt ? 0 : -ENOMEM; | |
2783 | } | |
2784 | ||
2785 | int ip_route_output_flow(struct net *net, struct rtable **rp, struct flowi *flp, | |
2786 | struct sock *sk, int flags) | |
2787 | { | |
2788 | int err; | |
2789 | ||
2790 | if ((err = __ip_route_output_key(net, rp, flp)) != 0) | |
2791 | return err; | |
2792 | ||
2793 | if (flp->proto) { | |
2794 | if (!flp->fl4_src) | |
2795 | flp->fl4_src = (*rp)->rt_src; | |
2796 | if (!flp->fl4_dst) | |
2797 | flp->fl4_dst = (*rp)->rt_dst; | |
2798 | err = __xfrm_lookup(net, (struct dst_entry **)rp, flp, sk, | |
2799 | flags ? XFRM_LOOKUP_WAIT : 0); | |
2800 | if (err == -EREMOTE) | |
2801 | err = ipv4_dst_blackhole(net, rp, flp); | |
2802 | ||
2803 | return err; | |
2804 | } | |
2805 | ||
2806 | return 0; | |
2807 | } | |
2808 | EXPORT_SYMBOL_GPL(ip_route_output_flow); | |
2809 | ||
2810 | int ip_route_output_key(struct net *net, struct rtable **rp, struct flowi *flp) | |
2811 | { | |
2812 | return ip_route_output_flow(net, rp, flp, NULL, 0); | |
2813 | } | |
2814 | EXPORT_SYMBOL(ip_route_output_key); | |
2815 | ||
2816 | static int rt_fill_info(struct net *net, | |
2817 | struct sk_buff *skb, u32 pid, u32 seq, int event, | |
2818 | int nowait, unsigned int flags) | |
2819 | { | |
2820 | struct rtable *rt = skb_rtable(skb); | |
2821 | struct rtmsg *r; | |
2822 | struct nlmsghdr *nlh; | |
2823 | long expires; | |
2824 | u32 id = 0, ts = 0, tsage = 0, error; | |
2825 | ||
2826 | nlh = nlmsg_put(skb, pid, seq, event, sizeof(*r), flags); | |
2827 | if (nlh == NULL) | |
2828 | return -EMSGSIZE; | |
2829 | ||
2830 | r = nlmsg_data(nlh); | |
2831 | r->rtm_family = AF_INET; | |
2832 | r->rtm_dst_len = 32; | |
2833 | r->rtm_src_len = 0; | |
2834 | r->rtm_tos = rt->fl.fl4_tos; | |
2835 | r->rtm_table = RT_TABLE_MAIN; | |
2836 | NLA_PUT_U32(skb, RTA_TABLE, RT_TABLE_MAIN); | |
2837 | r->rtm_type = rt->rt_type; | |
2838 | r->rtm_scope = RT_SCOPE_UNIVERSE; | |
2839 | r->rtm_protocol = RTPROT_UNSPEC; | |
2840 | r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED; | |
2841 | if (rt->rt_flags & RTCF_NOTIFY) | |
2842 | r->rtm_flags |= RTM_F_NOTIFY; | |
2843 | ||
2844 | NLA_PUT_BE32(skb, RTA_DST, rt->rt_dst); | |
2845 | ||
2846 | if (rt->fl.fl4_src) { | |
2847 | r->rtm_src_len = 32; | |
2848 | NLA_PUT_BE32(skb, RTA_SRC, rt->fl.fl4_src); | |
2849 | } | |
2850 | if (rt->dst.dev) | |
2851 | NLA_PUT_U32(skb, RTA_OIF, rt->dst.dev->ifindex); | |
2852 | #ifdef CONFIG_NET_CLS_ROUTE | |
2853 | if (rt->dst.tclassid) | |
2854 | NLA_PUT_U32(skb, RTA_FLOW, rt->dst.tclassid); | |
2855 | #endif | |
2856 | if (rt->fl.iif) | |
2857 | NLA_PUT_BE32(skb, RTA_PREFSRC, rt->rt_spec_dst); | |
2858 | else if (rt->rt_src != rt->fl.fl4_src) | |
2859 | NLA_PUT_BE32(skb, RTA_PREFSRC, rt->rt_src); | |
2860 | ||
2861 | if (rt->rt_dst != rt->rt_gateway) | |
2862 | NLA_PUT_BE32(skb, RTA_GATEWAY, rt->rt_gateway); | |
2863 | ||
2864 | if (rtnetlink_put_metrics(skb, rt->dst.metrics) < 0) | |
2865 | goto nla_put_failure; | |
2866 | ||
2867 | if (rt->fl.mark) | |
2868 | NLA_PUT_BE32(skb, RTA_MARK, rt->fl.mark); | |
2869 | ||
2870 | error = rt->dst.error; | |
2871 | expires = rt->dst.expires ? rt->dst.expires - jiffies : 0; | |
2872 | if (rt->peer) { | |
2873 | inet_peer_refcheck(rt->peer); | |
2874 | id = atomic_read(&rt->peer->ip_id_count) & 0xffff; | |
2875 | if (rt->peer->tcp_ts_stamp) { | |
2876 | ts = rt->peer->tcp_ts; | |
2877 | tsage = get_seconds() - rt->peer->tcp_ts_stamp; | |
2878 | } | |
2879 | } | |
2880 | ||
2881 | if (rt->fl.iif) { | |
2882 | #ifdef CONFIG_IP_MROUTE | |
2883 | __be32 dst = rt->rt_dst; | |
2884 | ||
2885 | if (ipv4_is_multicast(dst) && !ipv4_is_local_multicast(dst) && | |
2886 | IPV4_DEVCONF_ALL(net, MC_FORWARDING)) { | |
2887 | int err = ipmr_get_route(net, skb, r, nowait); | |
2888 | if (err <= 0) { | |
2889 | if (!nowait) { | |
2890 | if (err == 0) | |
2891 | return 0; | |
2892 | goto nla_put_failure; | |
2893 | } else { | |
2894 | if (err == -EMSGSIZE) | |
2895 | goto nla_put_failure; | |
2896 | error = err; | |
2897 | } | |
2898 | } | |
2899 | } else | |
2900 | #endif | |
2901 | NLA_PUT_U32(skb, RTA_IIF, rt->fl.iif); | |
2902 | } | |
2903 | ||
2904 | if (rtnl_put_cacheinfo(skb, &rt->dst, id, ts, tsage, | |
2905 | expires, error) < 0) | |
2906 | goto nla_put_failure; | |
2907 | ||
2908 | return nlmsg_end(skb, nlh); | |
2909 | ||
2910 | nla_put_failure: | |
2911 | nlmsg_cancel(skb, nlh); | |
2912 | return -EMSGSIZE; | |
2913 | } | |
2914 | ||
2915 | static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg) | |
2916 | { | |
2917 | struct net *net = sock_net(in_skb->sk); | |
2918 | struct rtmsg *rtm; | |
2919 | struct nlattr *tb[RTA_MAX+1]; | |
2920 | struct rtable *rt = NULL; | |
2921 | __be32 dst = 0; | |
2922 | __be32 src = 0; | |
2923 | u32 iif; | |
2924 | int err; | |
2925 | int mark; | |
2926 | struct sk_buff *skb; | |
2927 | ||
2928 | err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy); | |
2929 | if (err < 0) | |
2930 | goto errout; | |
2931 | ||
2932 | rtm = nlmsg_data(nlh); | |
2933 | ||
2934 | skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); | |
2935 | if (skb == NULL) { | |
2936 | err = -ENOBUFS; | |
2937 | goto errout; | |
2938 | } | |
2939 | ||
2940 | /* Reserve room for dummy headers, this skb can pass | |
2941 | through good chunk of routing engine. | |
2942 | */ | |
2943 | skb_reset_mac_header(skb); | |
2944 | skb_reset_network_header(skb); | |
2945 | ||
2946 | /* Bugfix: need to give ip_route_input enough of an IP header to not gag. */ | |
2947 | ip_hdr(skb)->protocol = IPPROTO_ICMP; | |
2948 | skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr)); | |
2949 | ||
2950 | src = tb[RTA_SRC] ? nla_get_be32(tb[RTA_SRC]) : 0; | |
2951 | dst = tb[RTA_DST] ? nla_get_be32(tb[RTA_DST]) : 0; | |
2952 | iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0; | |
2953 | mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0; | |
2954 | ||
2955 | if (iif) { | |
2956 | struct net_device *dev; | |
2957 | ||
2958 | dev = __dev_get_by_index(net, iif); | |
2959 | if (dev == NULL) { | |
2960 | err = -ENODEV; | |
2961 | goto errout_free; | |
2962 | } | |
2963 | ||
2964 | skb->protocol = htons(ETH_P_IP); | |
2965 | skb->dev = dev; | |
2966 | skb->mark = mark; | |
2967 | local_bh_disable(); | |
2968 | err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev); | |
2969 | local_bh_enable(); | |
2970 | ||
2971 | rt = skb_rtable(skb); | |
2972 | if (err == 0 && rt->dst.error) | |
2973 | err = -rt->dst.error; | |
2974 | } else { | |
2975 | struct flowi fl = { | |
2976 | .nl_u = { | |
2977 | .ip4_u = { | |
2978 | .daddr = dst, | |
2979 | .saddr = src, | |
2980 | .tos = rtm->rtm_tos, | |
2981 | }, | |
2982 | }, | |
2983 | .oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0, | |
2984 | .mark = mark, | |
2985 | }; | |
2986 | err = ip_route_output_key(net, &rt, &fl); | |
2987 | } | |
2988 | ||
2989 | if (err) | |
2990 | goto errout_free; | |
2991 | ||
2992 | skb_dst_set(skb, &rt->dst); | |
2993 | if (rtm->rtm_flags & RTM_F_NOTIFY) | |
2994 | rt->rt_flags |= RTCF_NOTIFY; | |
2995 | ||
2996 | err = rt_fill_info(net, skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq, | |
2997 | RTM_NEWROUTE, 0, 0); | |
2998 | if (err <= 0) | |
2999 | goto errout_free; | |
3000 | ||
3001 | err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid); | |
3002 | errout: | |
3003 | return err; | |
3004 | ||
3005 | errout_free: | |
3006 | kfree_skb(skb); | |
3007 | goto errout; | |
3008 | } | |
3009 | ||
3010 | int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb) | |
3011 | { | |
3012 | struct rtable *rt; | |
3013 | int h, s_h; | |
3014 | int idx, s_idx; | |
3015 | struct net *net; | |
3016 | ||
3017 | net = sock_net(skb->sk); | |
3018 | ||
3019 | s_h = cb->args[0]; | |
3020 | if (s_h < 0) | |
3021 | s_h = 0; | |
3022 | s_idx = idx = cb->args[1]; | |
3023 | for (h = s_h; h <= rt_hash_mask; h++, s_idx = 0) { | |
3024 | if (!rt_hash_table[h].chain) | |
3025 | continue; | |
3026 | rcu_read_lock_bh(); | |
3027 | for (rt = rcu_dereference_bh(rt_hash_table[h].chain), idx = 0; rt; | |
3028 | rt = rcu_dereference_bh(rt->dst.rt_next), idx++) { | |
3029 | if (!net_eq(dev_net(rt->dst.dev), net) || idx < s_idx) | |
3030 | continue; | |
3031 | if (rt_is_expired(rt)) | |
3032 | continue; | |
3033 | skb_dst_set_noref(skb, &rt->dst); | |
3034 | if (rt_fill_info(net, skb, NETLINK_CB(cb->skb).pid, | |
3035 | cb->nlh->nlmsg_seq, RTM_NEWROUTE, | |
3036 | 1, NLM_F_MULTI) <= 0) { | |
3037 | skb_dst_drop(skb); | |
3038 | rcu_read_unlock_bh(); | |
3039 | goto done; | |
3040 | } | |
3041 | skb_dst_drop(skb); | |
3042 | } | |
3043 | rcu_read_unlock_bh(); | |
3044 | } | |
3045 | ||
3046 | done: | |
3047 | cb->args[0] = h; | |
3048 | cb->args[1] = idx; | |
3049 | return skb->len; | |
3050 | } | |
3051 | ||
3052 | void ip_rt_multicast_event(struct in_device *in_dev) | |
3053 | { | |
3054 | rt_cache_flush(dev_net(in_dev->dev), 0); | |
3055 | } | |
3056 | ||
3057 | #ifdef CONFIG_SYSCTL | |
3058 | static int ipv4_sysctl_rtcache_flush(ctl_table *__ctl, int write, | |
3059 | void __user *buffer, | |
3060 | size_t *lenp, loff_t *ppos) | |
3061 | { | |
3062 | if (write) { | |
3063 | int flush_delay; | |
3064 | ctl_table ctl; | |
3065 | struct net *net; | |
3066 | ||
3067 | memcpy(&ctl, __ctl, sizeof(ctl)); | |
3068 | ctl.data = &flush_delay; | |
3069 | proc_dointvec(&ctl, write, buffer, lenp, ppos); | |
3070 | ||
3071 | net = (struct net *)__ctl->extra1; | |
3072 | rt_cache_flush(net, flush_delay); | |
3073 | return 0; | |
3074 | } | |
3075 | ||
3076 | return -EINVAL; | |
3077 | } | |
3078 | ||
3079 | static ctl_table ipv4_route_table[] = { | |
3080 | { | |
3081 | .procname = "gc_thresh", | |
3082 | .data = &ipv4_dst_ops.gc_thresh, | |
3083 | .maxlen = sizeof(int), | |
3084 | .mode = 0644, | |
3085 | .proc_handler = proc_dointvec, | |
3086 | }, | |
3087 | { | |
3088 | .procname = "max_size", | |
3089 | .data = &ip_rt_max_size, | |
3090 | .maxlen = sizeof(int), | |
3091 | .mode = 0644, | |
3092 | .proc_handler = proc_dointvec, | |
3093 | }, | |
3094 | { | |
3095 | /* Deprecated. Use gc_min_interval_ms */ | |
3096 | ||
3097 | .procname = "gc_min_interval", | |
3098 | .data = &ip_rt_gc_min_interval, | |
3099 | .maxlen = sizeof(int), | |
3100 | .mode = 0644, | |
3101 | .proc_handler = proc_dointvec_jiffies, | |
3102 | }, | |
3103 | { | |
3104 | .procname = "gc_min_interval_ms", | |
3105 | .data = &ip_rt_gc_min_interval, | |
3106 | .maxlen = sizeof(int), | |
3107 | .mode = 0644, | |
3108 | .proc_handler = proc_dointvec_ms_jiffies, | |
3109 | }, | |
3110 | { | |
3111 | .procname = "gc_timeout", | |
3112 | .data = &ip_rt_gc_timeout, | |
3113 | .maxlen = sizeof(int), | |
3114 | .mode = 0644, | |
3115 | .proc_handler = proc_dointvec_jiffies, | |
3116 | }, | |
3117 | { | |
3118 | .procname = "gc_interval", | |
3119 | .data = &ip_rt_gc_interval, | |
3120 | .maxlen = sizeof(int), | |
3121 | .mode = 0644, | |
3122 | .proc_handler = proc_dointvec_jiffies, | |
3123 | }, | |
3124 | { | |
3125 | .procname = "redirect_load", | |
3126 | .data = &ip_rt_redirect_load, | |
3127 | .maxlen = sizeof(int), | |
3128 | .mode = 0644, | |
3129 | .proc_handler = proc_dointvec, | |
3130 | }, | |
3131 | { | |
3132 | .procname = "redirect_number", | |
3133 | .data = &ip_rt_redirect_number, | |
3134 | .maxlen = sizeof(int), | |
3135 | .mode = 0644, | |
3136 | .proc_handler = proc_dointvec, | |
3137 | }, | |
3138 | { | |
3139 | .procname = "redirect_silence", | |
3140 | .data = &ip_rt_redirect_silence, | |
3141 | .maxlen = sizeof(int), | |
3142 | .mode = 0644, | |
3143 | .proc_handler = proc_dointvec, | |
3144 | }, | |
3145 | { | |
3146 | .procname = "error_cost", | |
3147 | .data = &ip_rt_error_cost, | |
3148 | .maxlen = sizeof(int), | |
3149 | .mode = 0644, | |
3150 | .proc_handler = proc_dointvec, | |
3151 | }, | |
3152 | { | |
3153 | .procname = "error_burst", | |
3154 | .data = &ip_rt_error_burst, | |
3155 | .maxlen = sizeof(int), | |
3156 | .mode = 0644, | |
3157 | .proc_handler = proc_dointvec, | |
3158 | }, | |
3159 | { | |
3160 | .procname = "gc_elasticity", | |
3161 | .data = &ip_rt_gc_elasticity, | |
3162 | .maxlen = sizeof(int), | |
3163 | .mode = 0644, | |
3164 | .proc_handler = proc_dointvec, | |
3165 | }, | |
3166 | { | |
3167 | .procname = "mtu_expires", | |
3168 | .data = &ip_rt_mtu_expires, | |
3169 | .maxlen = sizeof(int), | |
3170 | .mode = 0644, | |
3171 | .proc_handler = proc_dointvec_jiffies, | |
3172 | }, | |
3173 | { | |
3174 | .procname = "min_pmtu", | |
3175 | .data = &ip_rt_min_pmtu, | |
3176 | .maxlen = sizeof(int), | |
3177 | .mode = 0644, | |
3178 | .proc_handler = proc_dointvec, | |
3179 | }, | |
3180 | { | |
3181 | .procname = "min_adv_mss", | |
3182 | .data = &ip_rt_min_advmss, | |
3183 | .maxlen = sizeof(int), | |
3184 | .mode = 0644, | |
3185 | .proc_handler = proc_dointvec, | |
3186 | }, | |
3187 | { } | |
3188 | }; | |
3189 | ||
3190 | static struct ctl_table empty[1]; | |
3191 | ||
3192 | static struct ctl_table ipv4_skeleton[] = | |
3193 | { | |
3194 | { .procname = "route", | |
3195 | .mode = 0555, .child = ipv4_route_table}, | |
3196 | { .procname = "neigh", | |
3197 | .mode = 0555, .child = empty}, | |
3198 | { } | |
3199 | }; | |
3200 | ||
3201 | static __net_initdata struct ctl_path ipv4_path[] = { | |
3202 | { .procname = "net", }, | |
3203 | { .procname = "ipv4", }, | |
3204 | { }, | |
3205 | }; | |
3206 | ||
3207 | static struct ctl_table ipv4_route_flush_table[] = { | |
3208 | { | |
3209 | .procname = "flush", | |
3210 | .maxlen = sizeof(int), | |
3211 | .mode = 0200, | |
3212 | .proc_handler = ipv4_sysctl_rtcache_flush, | |
3213 | }, | |
3214 | { }, | |
3215 | }; | |
3216 | ||
3217 | static __net_initdata struct ctl_path ipv4_route_path[] = { | |
3218 | { .procname = "net", }, | |
3219 | { .procname = "ipv4", }, | |
3220 | { .procname = "route", }, | |
3221 | { }, | |
3222 | }; | |
3223 | ||
3224 | static __net_init int sysctl_route_net_init(struct net *net) | |
3225 | { | |
3226 | struct ctl_table *tbl; | |
3227 | ||
3228 | tbl = ipv4_route_flush_table; | |
3229 | if (!net_eq(net, &init_net)) { | |
3230 | tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL); | |
3231 | if (tbl == NULL) | |
3232 | goto err_dup; | |
3233 | } | |
3234 | tbl[0].extra1 = net; | |
3235 | ||
3236 | net->ipv4.route_hdr = | |
3237 | register_net_sysctl_table(net, ipv4_route_path, tbl); | |
3238 | if (net->ipv4.route_hdr == NULL) | |
3239 | goto err_reg; | |
3240 | return 0; | |
3241 | ||
3242 | err_reg: | |
3243 | if (tbl != ipv4_route_flush_table) | |
3244 | kfree(tbl); | |
3245 | err_dup: | |
3246 | return -ENOMEM; | |
3247 | } | |
3248 | ||
3249 | static __net_exit void sysctl_route_net_exit(struct net *net) | |
3250 | { | |
3251 | struct ctl_table *tbl; | |
3252 | ||
3253 | tbl = net->ipv4.route_hdr->ctl_table_arg; | |
3254 | unregister_net_sysctl_table(net->ipv4.route_hdr); | |
3255 | BUG_ON(tbl == ipv4_route_flush_table); | |
3256 | kfree(tbl); | |
3257 | } | |
3258 | ||
3259 | static __net_initdata struct pernet_operations sysctl_route_ops = { | |
3260 | .init = sysctl_route_net_init, | |
3261 | .exit = sysctl_route_net_exit, | |
3262 | }; | |
3263 | #endif | |
3264 | ||
3265 | static __net_init int rt_genid_init(struct net *net) | |
3266 | { | |
3267 | get_random_bytes(&net->ipv4.rt_genid, | |
3268 | sizeof(net->ipv4.rt_genid)); | |
3269 | return 0; | |
3270 | } | |
3271 | ||
3272 | static __net_initdata struct pernet_operations rt_genid_ops = { | |
3273 | .init = rt_genid_init, | |
3274 | }; | |
3275 | ||
3276 | ||
3277 | #ifdef CONFIG_NET_CLS_ROUTE | |
3278 | struct ip_rt_acct __percpu *ip_rt_acct __read_mostly; | |
3279 | #endif /* CONFIG_NET_CLS_ROUTE */ | |
3280 | ||
3281 | static __initdata unsigned long rhash_entries; | |
3282 | static int __init set_rhash_entries(char *str) | |
3283 | { | |
3284 | if (!str) | |
3285 | return 0; | |
3286 | rhash_entries = simple_strtoul(str, &str, 0); | |
3287 | return 1; | |
3288 | } | |
3289 | __setup("rhash_entries=", set_rhash_entries); | |
3290 | ||
3291 | int __init ip_rt_init(void) | |
3292 | { | |
3293 | int rc = 0; | |
3294 | ||
3295 | #ifdef CONFIG_NET_CLS_ROUTE | |
3296 | ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct)); | |
3297 | if (!ip_rt_acct) | |
3298 | panic("IP: failed to allocate ip_rt_acct\n"); | |
3299 | #endif | |
3300 | ||
3301 | ipv4_dst_ops.kmem_cachep = | |
3302 | kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0, | |
3303 | SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); | |
3304 | ||
3305 | ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep; | |
3306 | ||
3307 | if (dst_entries_init(&ipv4_dst_ops) < 0) | |
3308 | panic("IP: failed to allocate ipv4_dst_ops counter\n"); | |
3309 | ||
3310 | if (dst_entries_init(&ipv4_dst_blackhole_ops) < 0) | |
3311 | panic("IP: failed to allocate ipv4_dst_blackhole_ops counter\n"); | |
3312 | ||
3313 | rt_hash_table = (struct rt_hash_bucket *) | |
3314 | alloc_large_system_hash("IP route cache", | |
3315 | sizeof(struct rt_hash_bucket), | |
3316 | rhash_entries, | |
3317 | (totalram_pages >= 128 * 1024) ? | |
3318 | 15 : 17, | |
3319 | 0, | |
3320 | &rt_hash_log, | |
3321 | &rt_hash_mask, | |
3322 | rhash_entries ? 0 : 512 * 1024); | |
3323 | memset(rt_hash_table, 0, (rt_hash_mask + 1) * sizeof(struct rt_hash_bucket)); | |
3324 | rt_hash_lock_init(); | |
3325 | ||
3326 | ipv4_dst_ops.gc_thresh = (rt_hash_mask + 1); | |
3327 | ip_rt_max_size = (rt_hash_mask + 1) * 16; | |
3328 | ||
3329 | devinet_init(); | |
3330 | ip_fib_init(); | |
3331 | ||
3332 | /* All the timers, started at system startup tend | |
3333 | to synchronize. Perturb it a bit. | |
3334 | */ | |
3335 | INIT_DELAYED_WORK_DEFERRABLE(&expires_work, rt_worker_func); | |
3336 | expires_ljiffies = jiffies; | |
3337 | schedule_delayed_work(&expires_work, | |
3338 | net_random() % ip_rt_gc_interval + ip_rt_gc_interval); | |
3339 | ||
3340 | if (ip_rt_proc_init()) | |
3341 | printk(KERN_ERR "Unable to create route proc files\n"); | |
3342 | #ifdef CONFIG_XFRM | |
3343 | xfrm_init(); | |
3344 | xfrm4_init(ip_rt_max_size); | |
3345 | #endif | |
3346 | rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL); | |
3347 | ||
3348 | #ifdef CONFIG_SYSCTL | |
3349 | register_pernet_subsys(&sysctl_route_ops); | |
3350 | #endif | |
3351 | register_pernet_subsys(&rt_genid_ops); | |
3352 | return rc; | |
3353 | } | |
3354 | ||
3355 | #ifdef CONFIG_SYSCTL | |
3356 | /* | |
3357 | * We really need to sanitize the damn ipv4 init order, then all | |
3358 | * this nonsense will go away. | |
3359 | */ | |
3360 | void __init ip_static_sysctl_init(void) | |
3361 | { | |
3362 | register_sysctl_paths(ipv4_path, ipv4_skeleton); | |
3363 | } | |
3364 | #endif |